CN111376858B - Working vehicle - Google Patents

Abstract

The invention provides a work vehicle capable of effectively utilizing the lateral space of an oil cooler to save space. The work vehicle is provided with a check valve (400) which is formed in an elongated shape and allows oil to flow in the check valve from one side in the longitudinal direction to the other side in the longitudinal direction according to the hydraulic pressure on one side in the longitudinal direction of the check valve, wherein the end of one side in the longitudinal direction of the check valve (400) is connected to a first connection part (510) which connects an inlet port (62) and an oil outlet path (200), and the end of the other side in the longitudinal direction of the check valve (400) is connected to a second connection part (520) which connects an outlet port (63) and an oil circuit (300), and the check valve (400) is arranged in the longitudinal direction to be oriented in the up-down direction.

Description

Working vehicle

Technical Field

The present invention relates to a technique of a work vehicle including an oil cooler.

Background

Conventionally, a work vehicle equipped with an oil cooler has been known. For example, patent document 1 describes the present invention.

Patent document 1 describes a tractor provided with an oil cooler connected to an oil delivery hose (oil supply passage) for introducing oil and an oil delivery hose (oil discharge passage) for discharging oil. The oil cooler has a substantially rectangular outer shape elongated in the left-right direction when viewed from the front, and has an oil supply passage connected to one end in the left-right direction from below and an oil discharge passage connected to the other end in the left-right direction from below.

Further, a check valve is provided in the oil cooler. The check valve is disposed below the oil cooler, one end in the longitudinal direction is connected to the inlet hose, and the other end in the longitudinal direction is connected to the outlet hose. In this way, in the tractor, the space below the oil cooler is effectively utilized.

However, in the tractor described in patent document 1, the following is not assumed: for example, there is no consideration for effective use of the space laterally of the oil cooler in this case, in which two oil passages, i.e., an oil supply passage and an oil discharge passage, are connected from the side to one end in the lateral direction of the oil cooler, and a check valve is provided.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2009-173240

Disclosure of Invention

Technical problem to be solved by the invention

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a work vehicle capable of effectively utilizing a space on a side of an oil cooler and realizing space saving.

Technical means for solving the technical problems

The technical problem to be solved by the present invention is as described above, and a solution for solving the technical problem will be described next.

That is, according to claim 1, the work vehicle includes: an oil cooler formed in a substantially rectangular shape when viewed from the front, the oil cooler having connection ports at the upper and lower sides of one side in the lateral direction; an oil supply passage that is connected to the connection port of either one of the upper and lower portions and that supplies oil to the oil cooler; an oil discharge passage that is connected to the connection port of the other of the upper and lower side and that discharges oil from the oil cooler; and a valve that is formed in an elongated shape and that allows oil to flow in the valve from one side in a longitudinal direction toward the other side in the longitudinal direction according to a hydraulic pressure on the one side in the longitudinal direction of the valve, wherein an end portion on the one side in the longitudinal direction of the valve is connected to a first connection portion that connects one of the connection ports to the oil supply oil passage, and an end portion on the other side in the longitudinal direction of the valve is connected to a second connection portion that connects the other of the connection ports to the oil discharge oil passage, and the valve is arranged in the longitudinal direction.

In claim 2, the valve includes a plurality of tubular members configured to allow oil to flow in the longitudinal direction, the plurality of tubular members including one tubular member and another tubular member adjacent to each other in the longitudinal direction, and a portion of the one tubular member and the other tubular member at which positions in the longitudinal direction overlap each other is inserted into one of the other tubular members so as to be capable of moving relative to the other tubular member via a substantially annular first seal member.

In claim 3, the plurality of cylindrical members includes: a lower member connected to the first connection portion; an upper member connected to the second connection portion; and an intermediate member that is provided between the lower member and the upper member in the longitudinal direction and that is adjacent to the lower member and the upper member, wherein the lower member and the intermediate member are inserted as the one tubular member and the other tubular member, respectively, one of which is inserted into the other, and the upper member and the intermediate member are inserted as the one tubular member and the other tubular member, respectively.

In claim 4, the intermediate member has: a valve seat provided inside the intermediate member; a valve body slidably provided in the middle member in the longitudinal direction; and a biasing member that biases the valve element toward the valve seat against the hydraulic pressure on the longitudinal side.

In claim 5, the valve has a first through hole penetrating an end portion of the valve on one side in the longitudinal direction in the lateral direction, and the valve is connected to the first connecting portion via a first fastening member inserted through the first through hole on the other side in the lateral direction.

In claim 6, the valve has a second through hole penetrating an end portion of the valve on the other side in the longitudinal direction in the lateral direction, and the valve is connected to the second connection portion via a second fastening member inserted through the second through hole on the other side in the lateral direction.

In claim 7, the end portion of the oil discharge passage on the second connection portion side is arranged such that the longitudinal direction of the end portion on the second connection portion side is oriented in the up-down direction, and the end portion on the second connection portion side is adjacent to the valve.

In claim 8, the first-connection-side end portion of the oil supply passage is disposed such that a longitudinal direction of the first-connection-side end portion is oriented in the up-down direction, and the first-connection-side end portion extends downward from the valve.

In claim 9, an end portion of the oil supply passage on the first connection portion side is provided with: a first supply oil passage side connection portion that is included in the first connection portion and has a third through hole that penetrates in the left-right direction; a flow path portion that serves as a flow path for oil; and a fixing means for fixing the first supply oil passage side connection portion and the flow path portion, wherein the first supply oil passage side connection portion is connected to one of the connection ports via a third fastening member that is inserted through the third through hole to the other side in the lateral direction, and the first supply oil passage side connection portion is fixed to the flow path portion by the fixing means in a state of being connected to the flow path portion so as to be relatively movable.

In claim 10, the oil cooler is disposed inside the engine cover, and the oil cooler is disposed in front of the engine.

Effects of the invention

The effects of the present invention are as follows.

In claim 1, the space on the side of the oil cooler can be effectively utilized, and space saving can be achieved.

In claim 2, the vertical deviation of the valve can be absorbed, and the assembling property and the workability can be improved.

In claim 3, since the intermediate member can be moved in the longitudinal direction relative to the lower member and the upper member, the vertical variation of the valve can be absorbed, and the assembling property and the workability can be improved.

In claim 4, in the valve formed by combining a plurality of members, since the main structure is integrated into one member (intermediate member), the structure of the entire valve can be simplified.

In claim 5, when assembling, the valve can be swung in the front-rear direction with the end on one side in the longitudinal direction of the valve as the center, and therefore, the assembling property and workability can be improved.

In claim 6, when assembling, the valve can be swung in the front-rear direction with the end portion on the other side in the longitudinal direction of the valve as the center, and therefore, the assembling property and the workability can be improved.

In claim 7, the space on the side of the oil cooler can be effectively utilized, and space saving can be achieved.

In claim 8, the space on the side of the oil cooler can be effectively utilized, and space saving can be achieved.

In claim 9, the assembling property and the workability can be improved.

In claim 10, the space on the side of the oil cooler can be effectively utilized in front of the engine in the engine cover, and space saving can be achieved.

Drawings

Fig. 1 is a right side view showing an overall structure of a tractor according to an embodiment of the present invention.

Fig. 2 is a perspective view showing a front portion of a tractor according to an embodiment of the present invention.

Fig. 3 is a perspective view showing the inside of the engine cover.

Fig. 4 is a partially enlarged perspective view showing the inside of the engine cover.

Fig. 5 is a left side view showing the right rectifying plate and the right suction port.

Fig. 6 is a right side view showing the left rectifying plate and the left air inlet.

Fig. 7 is a right side view showing an arrangement structure around the cooler.

Fig. 8 is a left side view showing an arrangement structure around the cooler.

Fig. 9 is a plan view showing an arrangement structure around the cooler.

Fig. 10 is a right side view schematically showing a case where air flows to the cooler.

Fig. 11 is a left side view schematically showing a case where air flows to the cooler.

Fig. 12 is a right side plan view showing a case where air flows to the cooler.

Fig. 13 is a left side plan view showing a case where air flows to the cooler.

Fig. 14 is a front view showing an oil introduction/discharge structure.

Fig. 15 is a perspective view showing an oil introduction/discharge structure.

Fig. 16 (a) is a right side view showing an oil cooler and an oil introduction/discharge structure, and fig. 16 (b) is a view in which a part of fig. 16 (a) is omitted.

Fig. 17 (a) is a front view showing a downstream end portion of the oil outlet path, and fig. 17 (b) is a front cross-sectional view of fig. 17 (a).

Fig. 18 (a) is a front view showing a check valve, and fig. 18 (b) is a front sectional view showing a check valve.

Fig. 19 (a) is a front cross-sectional view showing an intermediate member of the check valve, and fig. 19 (b) is an exploded front cross-sectional view showing an intermediate member of the check valve.

Fig. 20 is a front cross-sectional view of an intermediate member of the check valve showing an open state.

Fig. 21 is a front cross-sectional view showing an oil introduction/discharge structure.

Fig. 22 is an exploded perspective view showing an oil introduction/discharge structure.

Fig. 23 (a) is a schematic front sectional view showing the check valve before the full length change, and fig. 23 (b) is a schematic front sectional view showing the check valve after the full length change.

Fig. 24 is a schematic front cross-sectional view showing a flow pattern of oil in the oil introduction/discharge structure when the check valve is in a closed state.

Fig. 25 is a schematic front cross-sectional view showing a flow pattern of oil in the oil introduction/discharge structure when the check valve is in an open state.

Fig. 26 (a) is a front view showing the block joint and the bracket, and fig. 26 (b) is a plan view showing the block joint and the bracket.

Fig. 27 (a) is a right side view showing the block joint and the bracket, and fig. 27 (b) is a right side partial sectional view showing the block joint and the bracket.

Fig. 28 is a right side view showing a mounted state of the block joint.

Fig. 29 is a side partial cross-sectional view showing a pipe connection state of the block joint.

Fig. 30 is a front view showing a mounted state of the block joint.

Fig. 31 is a partial enlarged view of fig. 30.

Symbol description

1. Tractor

3. Engine with a motor

10. Engine hood

62. Inlet port

63. Export port

60. Oil cooler

200. Oil delivery

300. Oil circuit

400. Check valve

410. Lower part

420. Upper side member

430. Intermediate part

451. Upper side O-shaped ring

452. Lower O-shaped ring

510. First connecting part

520. Second connecting part

Detailed Description

In the following, directions indicated by arrows U, D, F, B, L, and R in the drawings are defined as an upper direction, a lower direction, a front direction, a rear direction, a left direction, and a right direction, respectively.

First, the overall structure of a tractor 1 according to an embodiment of the present invention will be described with reference to fig. 1 to 4. In fig. 4, the condenser 80 and the right rectifying plate 110 described later are omitted from the configuration illustrated in fig. 3 for convenience.

The tractor 1 mainly includes: the engine includes a body frame 2, an engine 3, a flywheel housing 4, a clutch housing 5, a transmission 6, a lifter 7, front wheels 8, rear wheels 9, a hood 10, a muffler 11, a cab 12, a steering wheel 13, a seat 14, and the like.

The body frame 2 is a frame-like member formed by appropriately combining a plurality of plates. The body frame 2 is disposed in the front lower portion of the tractor 1 such that the longitudinal direction thereof is oriented in the front-rear direction. An engine 3 is fixed to the rear of the body frame 2. A flywheel housing 4 is fixed to the rear of the engine 3. A clutch housing 5 is fixed to the rear of the flywheel housing 4. A transmission case 6 is fixed to the rear portion of the clutch housing 5. A lifting device 7 is provided at the rear of the gearbox 6. Various working devices (e.g., a cultivator) can be mounted on the lifting device 7.

The front portion of the body frame 2 is supported by a pair of left and right front wheels 8 via a front axle mechanism (not shown). The transmission case 6 is supported by a pair of left and right rear wheels 9 via a rear axle mechanism (not shown).

In addition, the engine 3 is covered with the engine cover 10. The hood 10 is rotatably supported by a hood support member 24 fixed to the upper portion of the flywheel housing 4 shown in fig. 3. As shown in fig. 3 and 4, a cooling fan 40 is provided in front of the engine 3 inside the engine cover 10. A cooling unit 90 cooled by the cooling fan 40, the battery 16, and the air cleaner 17 are provided in front of the cooling fan 40. Rectifying plates 100 are provided on the left and right sides of the cooling unit 90. A muffler 11 that discharges exhaust gas of the engine 3 is disposed on the left side of the engine cover 10. A cab 12 is provided behind the hood 10. A steering wheel 13, a seat 14, various operating tools, pedals, and the like are disposed inside the cab 12.

The power of the engine 3 can be transmitted to the front wheels 8 through the front axle mechanism after being shifted by a transmission (not shown) housed in the transmission case 6, and can be transmitted to the rear wheels 9 through the rear axle mechanism. In this way, the front wheels 8 and the rear wheels 9 are driven to rotate by the power of the engine 3, and the tractor 1 can travel. Further, the working device attached to the lifting device 7 can be driven by the power of the engine 3. In addition, the cooling fan 40 can be driven by the power of the engine 3.

The structure of the engine cover 10 will be described in detail below with reference to fig. 2, 5 and 6.

The hood 10 is formed in a substantially box shape with the rear and lower sides open. The hood 10 includes an upper surface portion 26, a front surface portion 27, and side surface portions 28.

The upper surface portion 26 constitutes a ceiling of the engine cover 10. The upper surface portion 26 is formed in a shape inclined downward as going forward. The front portion of the upper surface portion 26 is formed in a shape in which the tip becomes thinner as it goes forward in plan view.

The front surface portion 27 constitutes a front plate of the engine cover 10. The upper end of the front surface portion 27 is connected to the front end of the upper surface portion 26.

The side surface portions 28 constitute left and right side plates of the engine cover 10. The side surface 28 is formed in a substantially rectangular shape with a rear lower portion cut away in side view. The upper ends of the side portions 28 are connected to the left and right side ends of the upper surface portion 26. The front end of the side surface 28 is connected to the left and right side ends of the front surface 27. The side surface 28 has a vent hole 30.

The vent hole 30 is a portion that sucks outside air into the engine cover 10. The vent hole 30 is formed by providing a mesh member to an opening portion of the through-side surface portion 28. The vent hole 30 is formed near the front end portion of the side surface portion 28. The vent hole 30 is formed in a substantially rectangular shape such that the width thereof in the up-down direction becomes smaller as it goes forward in a side view. The ventilation holes 30 are formed on the left and right sides of the side surface 28. As shown in fig. 5 and 6, the left and right ventilation holes 30 are formed in a left and right symmetrical shape.

By driving the cooling fan 40, air is sucked into the ventilation hole 30. The air sucked from the vent hole 30 is adjusted to flow by the rectifying plate 100 and is guided to the cooling unit 90 (the radiator 50, the oil cooler 60, the fuel cooler 70, and the condenser 80). Hereinafter, the right vent hole 30 is referred to as a "right vent hole 31", and the left vent hole 30 is referred to as a "left vent hole 32".

Hereinafter, the structure in which the air sucked from the right side ventilation hole 31 and the left side ventilation hole 32 is guided to the cooling unit 90 by the flow straightening plate 100 will be described in detail.

The cooling unit 90 is an aggregate of coolers that cool a fluid to be cooled. In the present embodiment, the cooling unit 90 includes a radiator 50, an oil cooler 60, a fuel cooler 70, and a condenser 80.

First, the structure of the rectification plate 100 will be described in detail with reference to fig. 5 and 6.

As described above, the rectifying plates 100 are provided on the left and right sides of the cooling unit 90. Hereinafter, the right rectifying plate 100 is referred to as "right rectifying plate 110", and the left rectifying plate 100 is referred to as "left rectifying plate 150".

The right rectifying plate 110 shown in fig. 5 mainly adjusts the flow of air sucked from the right vent hole 31. The right rectifying plate 110 is formed of a plate-like member having a substantially rectangular shape when viewed from the side in which the plate surface faces the left-right direction. The right rectifying plate 110 is erected upward from a substantially flat plate-like support base 21 mounted on the body frame 2 (see fig. 3). The right rectifying plate 110 includes a right first portion 111, a right second portion 112, and a right cutout 120.

The right first portion 111 is a portion provided at the lower portion of the right rectifying plate 110 and having a substantially rectangular shape when viewed from the side. The front end of the right first portion 111 constitutes the front end of the right rectifying plate 110. That is, the front end of the right first portion 111 is located at the same position as the front end of the right rectifying plate 110. Hereinafter, the position of the front end of the right first portion 111 in the front-rear direction is referred to as "front position RF1". In addition, the upper end of the right first portion is located at a height slightly lower than 3/4 of the height of the right rectifying plate 110. In the following, the position in the up-down direction of the upper end of the right first portion 111 is referred to as "height position RH1".

The right second portion 112 is a portion provided at an upper portion of the right rectifying plate 110 and having a substantially rectangular shape when viewed from the side. The right second portion 112 is integrally formed with the right first portion 111. The front end of the right second portion 112 is located rearward of the front end of the right rectifying plate 110. More specifically, the front end of the right second portion 112 is located slightly rearward of the front-rear direction central portion of the right rectifying plate 110. In the following, the front-rear direction position of the front end of the right second portion 112 is referred to as "front-side position RF2". In addition, the upper end of the right second portion constitutes the upper end of the right rectifying plate 110. That is, the upper end of the right second portion 112 is located at the same position as the upper end of the right rectifying plate 110. In the following, the position in the up-down direction of the upper end of the right second portion 112 is referred to as "height position RH2".

The right side cutout 120 is a portion formed by cutting the right side rectifying plate 110 appropriately. The right cutout 120 includes a right first cutout 121, a right second cutout 122, and a right third cutout 123.

The right first cutout 121 is a cutout formed to be surrounded by the upper end of the right first portion 111 and the front end of the right second portion 112. That is, the right first cutout 121 is formed to be open upward and forward. The rear end of the right first cutout 121 is located at the front position RF2 in the front-rear direction. In addition, the lower end of the right first cutout 121 is located at the height position RH1 in the up-down direction. In addition, the front end of the right first cutout 121 is located at the front position RF1 in the front-rear direction. The right first cutout portion 121 has a right corner portion 131.

The right corner 131 is a portion located at the rear lower end of the right first cutout 121. The right corner 131 is formed at a portion where the rear end (rear side) and the lower end (lower side) of the right first cutout 121 intersect. That is, the right corner 131 is formed by the upper end of the right first portion 111 and the front end of the right second portion 112 of the right rectifying plate 110 so that an angle formed by both sides is substantially 90 degrees in side view.

The right second cutout 122 is a cutout formed by cutting the front upper end of the right first portion 111. In other words, the right second notch 122 is a notch formed by forming a corner of the opening of the right first notch 121 that opens forward into a notch shape. The right second cutout 122 has a diagonally linear edge portion with an upper end located rearward and a lower end located forward.

The right third cutout 123 is a cutout formed by cutting the front upper end of the right second portion 112. In other words, the right third notch 123 is a notch formed by forming a corner of the upwardly open mouth of the right first notch 121 into a notch shape. The right third notch 123 has a linear edge with an upper end located rearward and a lower end located forward.

In this way, the right rectifying plate 110 is formed in a substantially rectangular shape that is long in the up-down direction as a whole and is cut off appropriately from the front side toward the rear side (substantially L-shaped). Further, a right vent hole 31 is disposed right of the right rectifying plate 110 (on the back side of the drawing sheet of fig. 5).

Here, when the shapes of the right vent hole 31 and the right rectifying plate 110 are compared with each other in a side view, the right vent hole 31 and the right rectifying plate 110 are formed to overlap each other except for a part of the front side of the right vent hole 31. Hereinafter, a portion of the front side of the right vent hole 31 is referred to as a "non-overlapping portion 31a".

The non-overlapping portion 31a of the right vent hole 31 is formed in a substantially V shape that is open rearward in a side view. The upper portion of the non-overlapping portion 31a is formed so as to be located in front of the lower portion of the right second portion 112 of the right rectifying plate 110 in side view and overlap with the lower portion of the right first cutout portion 121. The lower portion of the non-overlapping portion 31a is formed to be located in front of the upper portion of the right first portion 111 in side view and to overlap with the space in front of the upper portions of the right first cutout 121 and the right first portion 111.

In this way, the non-overlapping portion 31a of the right vent hole 31 is formed so as to cross the boundary portion between the right first cutout 121 and the right first portion 111 (the lower end of the right first cutout 121) in the vertical direction in a side view.

The left rectifying plate 150 shown in fig. 6 mainly adjusts the flow of air sucked from the left vent hole 32. The left rectifying plate 150 is formed of a plate-like member having a substantially rectangular shape when viewed from the side in which the plate surface faces the left-right direction. The left rectifying plate 150 is erected upward from the support base 21 mounted on the body frame 2, similarly to the right rectifying plate 110. The left rectifying plate 150 includes a left first portion 151, a left second portion 152, a left third portion 153, and a left cutout 160.

The left first portion 151 is a portion provided at the lower portion of the left rectifying plate 150 and having a substantially rectangular shape in side view. The front end of the left first portion 151 constitutes the front end of the left rectifying plate 150. That is, the front end of the left first portion 151 is located at the same position as the front end of the left rectifying plate 150. In the following, the front end of the left first portion 151 is located at a position in the front-rear direction, which is referred to as a "front position LF1". The upper end of the left first portion 151 is located slightly above the vertical central portion of the left rectifying plate 150. In the following, the position in the up-down direction of the upper end of the left first portion 151 is referred to as "height position LH1". The height position LH1 is formed at a position lower than the height position RH1 of the right rectification plate 110.

The left second portion 152 is a portion provided in the upper and lower middle portions of the left rectifying plate 150 and having a substantially rectangular shape in side view. The left second portion 152 is integrally formed with the left first portion 151. The front end of the left second portion 152 is located rearward of the front end of the left rectifying plate 150. More specifically, the front end of the left second portion 152 is located slightly forward of the front-rear direction central portion of the left rectifying plate 150. In the following, the position of the front end of the left second portion 152 in the front-rear direction is referred to as "front position LF2". In addition, the upper end of the left second portion is located at a height of about 3/4 of the height of the left rectifying plate 150. In the following, the position in the up-down direction of the upper end of the left second portion 152 is referred to as "height position LH2". The height position LH2 is formed at a position higher than the height position RH1 of the right rectification plate 110.

The left third portion 153 is a portion provided at the upper portion of the left rectifying plate 150 and having a substantially rectangular shape when viewed from the side. The left third portion 153 is integrally formed with the left second portion 152. The front end of the left third portion 153 is located slightly rearward of the front-rear direction central portion of the left rectifying plate 150. In the following, the position of the front end of the left third portion 153 in the front-rear direction is referred to as "front position LF3". In addition, the upper end of the left third portion constitutes the upper end of the left rectifying plate 150. That is, the upper end of the left third portion 153 is located at the same position as the upper end of the left rectifying plate 150. In the following, the position in the up-down direction of the upper end of the left third portion 153 is referred to as "height position LH3".

Further, the front position LF3 of the left third portion 153 is located at the same position as the front position RF2 of the right rectifying plate 110 in the front-rear direction. That is, the length of the left third portion 153 in the front-rear direction is formed to be the same as the length of the right second portion 112 of the right rectifying plate 110 in the front-rear direction.

The left cutout 160 is a portion formed by cutting the left rectifying plate 150 appropriately. The left cutout 160 includes a left first cutout 161, a left second cutout 162, a left third cutout 163, and a left fourth cutout 164.

The left first cutout 161 is a cutout portion formed to be surrounded by the upper end of the left second portion 152 and the front end of the left third portion 153. That is, the left first notch 161 is formed to be open upward and forward. The rear end of the left first cutout 161 is located at the front position LF3 in the front-rear direction. In addition, the lower end of the left first cutout 161 is located at a height position LH2 in the up-down direction. In addition, the front end of the left first cutout 161 is located at the front position LF1 in the front-rear direction. The left first cutout 161 has a left first corner 171.

The left first corner 171 is a portion located at the rear lower end of the left first cutout 161. The left first corner 171 is formed at a portion where the rear end (rear side) of the left first cutout 161 intersects with the lower end (lower side). That is, the left first corner 171 is formed by the upper end of the left second portion 152 and the front end of the left third portion 153 of the left rectifying plate 150 so that an angle formed by both sides in a side view is substantially 90 degrees.

The left second cutout 162 is a cutout formed to be surrounded by the upper end of the left first portion 151 and the front end of the left second portion 152. That is, the left second cutout 162 is formed to be open upward and forward. The rear end of the left second cutout portion 162 is located at the front position LF2 in the front-rear direction. In addition, the lower end of the left second cutout 162 is located at the height position LH1 in the up-down direction. In addition, the front end of the left second cutout portion 162 is located at the front position LF1 in the front-rear direction. The left second cutout portion 162 has a left second corner portion 172.

The left second corner 172 is a portion located at the rear lower end of the left second cutout 162. The left second corner 172 is formed at a portion where the rear end (rear side) of the left second cutout 162 intersects the lower end (lower side). That is, the left second corner 172 is formed by the upper end of the left first portion 151 and the front end of the left second portion 152 of the left rectifying plate 150 so that an angle formed by both sides in a side view is substantially 90 degrees.

The left third cutout 163 is a cutout formed by cutting the front upper end of the left first portion 151. In other words, the left third notch 163 is a notch formed by forming a corner of the opening of the left second notch 162 that opens forward into a notch shape. The left third notch 163 has a linear edge with an upper end located rearward and a lower end located forward.

The left fourth cutout 164 is a cutout formed by cutting the front upper end portion of the left third portion 153. In other words, the left fourth notch 164 is a notch formed by forming a corner of the upwardly open mouth of the left first notch 161 into a notch shape. The left fourth cutout 164 has a diagonally linear edge portion with an upper end located rearward and a lower end located forward.

In this way, the left rectifying plate 150 is formed in a substantially rectangular shape that is long in the vertical direction as a whole in side view, and is cut off appropriately from the front side toward the rear side (substantially L-shaped). The left rectifying plate 150 is formed in a stepped shape having a step that decreases as it advances forward by the left first notch 161 and the left second notch 162. Further, a left vent hole 32 is disposed in the left side of the left rectifying plate 150 (in the back side of the paper surface of fig. 6).

Here, when the shapes of the left vent hole 32 and the left rectifying plate 150 are compared with each other in a side view, the left vent hole 32 and the left rectifying plate 150 are formed to overlap each other except for a part of the front side of the left vent hole 32. Hereinafter, a portion of the front side of the left vent hole 32 is referred to as a "non-overlapping portion 32a".

The non-overlapping portion 32a of the left vent hole 32 is formed in a substantially V shape that is opened rearward in a side view. The upper portion of the non-overlapping portion 32a is formed so as to be located in front of the lower portion of the left third portion 153 of the left rectifying plate 150 in side view and overlap with the lower portion of the left first cutout portion 161. The center portion of the non-overlapping portion 32a is located in front of the left second portion 152 of the left rectifying plate 150 in a side view and overlaps with the left second cutout 162. The lower portion of the non-overlapping portion 32a is formed to be located in front of the upper portion of the left first portion 151 in side view and to overlap with the left third cutout 163 and the space in front of the upper portion of the left first portion 151.

In this way, the non-overlapping portion 32a of the left vent hole 32 is formed so as to vertically cross the boundary portion between the left first cutout portion 161 and the left second cutout portion 162 and the boundary portion between the left second cutout portion 162 and the left third cutout portion 163 in a side view. In other words, the non-overlapping portion 32a of the left vent hole 32 is formed so as to span the lower end of the left first cutout portion 161 and the lower end of the left second cutout portion 162 in the up-down direction.

The size of the entire left cutout 160 is larger than the size of the entire right cutout 120 of the right rectifying plate 110.

The following describes the structure of the cooling unit 90 (radiator 50, oil cooler 60, fuel cooler 70, and condenser 80) and the cooling fan 40 disposed behind the cooling unit 90 shown in fig. 3 and 4.

The cooling fan 40 is configured to be rotatable by power of the engine 3. The cooling fan 40 includes a fan cover 41.

The fan housing 41 houses a cooling fan 40 and a part of the radiator 50. The fan housing 41 is formed to penetrate in the front-rear direction at an inner portion (a portion where the cooling fan 40 is housed) of the fan housing 41. The fan cover 41 is fixed to the body frame 2, and is erected from the body frame 2.

The outer edge of the fan cover 41 is provided to block a gap (not shown) between the fan cover 41 and the inner surface of the engine cover 10. In this way, the front space and the rear space are partitioned by the fan cover 41 in the engine cover 10, and the front space and the rear space are communicated with each other substantially only by the inner portion of the fan cover 41.

The radiator 50 cools the cooling water of the engine 3. The radiator 50 is configured to be capable of circulating cooling water between the radiator 50 and the engine 3. The radiator 50 includes a radiator core 51 and an upper tank 52.

The radiator core 51 has a plurality of pipes through which cooling water flows and a plurality of radiating fins. The radiator core 51 has a substantially rectangular outer shape when viewed from the front, and is configured to allow air to pass through the radiator core 51 from the front to the rear. The upper tank 52 is formed to cover the upper end portion of the radiator core 51 from above.

In this way, the lower end portion of the radiator 50 is accommodated in the fan housing 41 and fixed to the body frame 2. The radiator core 51 of the radiator 50 is opposed to the cooling fan 40 in the front-rear direction at an inner portion of the fan cover 41.

The oil cooler 60 shown in fig. 4 cools oil (working oil) of a predetermined hydraulic machine or the like. The oil cooler 60 is configured to be capable of circulating oil between the oil cooler 60 and the hydraulic equipment and the like. The oil cooler 60 has a substantially rectangular outer shape when viewed from the front. The oil cooler 60 has a tube 61 for supplying oil to flow and radiating fins, and is configured to enable air to pass through the oil cooler 60 from the front to the rear. The oil cooler 60 is erected above the support table 21 via a predetermined frame.

The oil cooler 60 is provided with an oil inlet port 62 for introducing oil and an oil outlet port 63 for discharging oil (see fig. 14). An end portion of the oil outlet passage 200 through which the oil flows is connected to the inlet port 62. A block joint 250 (see fig. 3) is connected to a middle portion of the oil outlet passage 200. An end portion of the oil circuit 300 through which the oil flows is connected to the outlet port 63. Further, a check valve 400 of the oil cooler 60 is provided on the right side of the oil cooler 60. In this way, a structure for introducing oil into the oil cooler 60 and a structure for discharging oil from the oil cooler 60 (hereinafter referred to as "oil introduction/discharge structure") are provided on the right side of the oil cooler 60. The oil introduction/discharge structure will be described in detail below. The block joint 250 is described in detail below.

The fuel cooler 70 cools the fuel used in the engine 3. The fuel cooler 70 has a substantially rectangular outer shape when viewed from the front. The fuel cooler 70 has a tube through which fuel flows and a fin, and is configured to allow air to pass through the fuel cooler 70 from the front to the rear. The fuel cooler 70 is erected above the support table 21 via a predetermined frame.

The condenser 80 cools a refrigerant used in the air conditioner, and the condenser 80 has a substantially rectangular outer shape when viewed from the front. The condenser 80 has tubes through which a refrigerant flows and heat radiating fins, and is configured such that air can pass through the condenser 80 from the front to the rear. The condenser 80 is erected above the support table 21 via a predetermined frame.

The positional relationship between the cooling unit 90 (radiator 50, oil cooler 60, fuel cooler 70, and condenser 80) and the right and left rectifying plates 110, 150 will be described in detail below with reference to fig. 7 to 9.

As shown in fig. 7 to 9, a radiator 50 is disposed in front of the cooling fan 40. The radiator 50 is provided so as to extend in the up-down, left-right direction over an inner portion (portion penetrating in the front-rear direction) of the fan housing 41 accommodating the cooling fan 40. An oil cooler 60 and a fuel cooler 70 are disposed in front of the radiator 50.

The fuel cooler 70 is disposed above the oil cooler 60. That is, the fuel cooler 70 and the oil cooler 60 are located at the same position in the front-rear direction. In addition, the height of the upper end of the fuel cooler 70 is formed lower than the height of the upper end of the radiator 50.

The lengths of the oil cooler 60 and the fuel cooler 70 in the left-right direction are substantially the same as each other. The lengths of the oil cooler 60 and the fuel cooler 70 in the lateral direction are smaller than the lengths of the radiator 50 in the lateral direction. The oil cooler 60 and the fuel cooler 70 are disposed in front of the radiator 50 at positions offset to the left with respect to the radiator 50. That is, the left ends of the oil cooler 60 and the fuel cooler 70 are located at substantially the same position as the left end of the radiator 50 in the left-right direction. The right ends of the oil cooler 60 and the fuel cooler 70 are located to the left of the right end of the radiator 50 in the left-right direction. A condenser 80 is disposed in front of the oil cooler 60 and the fuel cooler 70.

The condenser 80 is formed to have a length in the lateral direction substantially equal to that of the radiator 50. In addition, the height of the upper end of the condenser 80 is formed to be substantially the same as the height of the upper end of the fuel cooler 70.

According to such a positional relationship, no other cooler is disposed in front of the upper range R1 of the radiator 50. Further, the condenser 80, the oil cooler 60, and the fuel cooler 70 are disposed in front of the lower range R2 of the radiator 50, in front of the left range R3, and only the condenser 80 is disposed in front of the right range R4.

As shown in fig. 7 and 9, the right rectifying plate 110 is disposed between the right vent hole 31 and the cooling unit 90, and is disposed so as to extend forward from the right end of the radiator 50 of the cooling unit 90. The front end of the right rectifying plate 110 is located forward of the condenser 80. That is, the right rectifying plate 110 is disposed to cover the cooling unit 90 (the radiator 50, the oil cooler 60, the fuel cooler 70, and the condenser 80) from the right side.

The rear end of the right first cutout 121 of the right rectifying plate 110 (the front position RF2 of the right rectifying plate 110) is formed so as to be located above the oil cooler 60 and the fuel cooler 70 in side view. In addition, the lower end of the right first cutout 121 of the right rectifying plate 110 (the height position RH1 of the right rectifying plate 110) is formed to be slightly higher than the upper ends of the condenser 80, the oil cooler 60, and the fuel cooler 70 in side view. The upper and lower ends of the right first cutout 121 of the right rectifying plate 110 (the height position RH2 and the height position RH1 of the right rectifying plate 110) are formed to have substantially the same height as the upper and lower ends of the range R1.

As shown in fig. 8 and 9, the left rectifying plate 150 is disposed between the left vent hole 32 and the cooling unit 90, and is disposed so as to extend forward from the left end of the radiator 50 of the cooling unit 90. The front end of the left rectifying plate 150 is located forward of the condenser 80. That is, the left rectifying plate 150 is disposed to cover the cooling unit 90 (the radiator 50, the oil cooler 60, the fuel cooler 70, and the condenser 80) from the left side.

The rear end of the left first cutout 161 of the left rectifying plate 150 (the front position LF3 of the left rectifying plate 150) is formed so as to be located above the oil cooler 60 and the fuel cooler 70 in side view. In addition, the rear end of the left second cutout 162 of the left rectifying plate 150 (the front position LF2 of the left rectifying plate 150) is formed to be located above the condenser 80 in side view. The lower end of the left second cutout 162 of the left rectifying plate 150 (the height position LH1 of the left rectifying plate 150) is formed to have substantially the same height as the upper ends of the condenser 80, the oil cooler 60, and the fuel cooler 70 in side view.

Thus, the cutouts of the right and left rectifying plates 110 and 150 are formed to correspond to the cooling units 90, respectively.

Next, a mode in which air sucked from the right side ventilation hole 31 and the left side ventilation hole 32 is guided to the cooling unit 90 by the rectifying plate 100 will be described specifically with reference to fig. 10 to 13.

The air that has hit the right rectifying plate 110, out of the air taken into the interior of the engine cover 10 via the right vent hole 31 by the driving of the cooling fan 40, is guided forward along the right rectifying plate 110. That is, the air taken into the engine hood 10 through the right vent hole 31 is restricted to be guided from the side (positive side) of the cooling unit 90 to the cooling unit 90 side, and flows in a forward detour through the right rectifying plate 110.

Then, of the air guided forward, the air reaching the right first cutout 121 is guided to the cooling unit 90 side through the right first cutout 121. Specifically, the air guided to the cooling unit 90 side through the right first cutout 121 is guided forward of the upper range R1 of the radiator 50. Here, no other cooler is disposed in front of the upper range R1 of the radiator 50. Therefore, in front of the upper range R1 of the radiator 50, the air is guided from a position relatively close to the radiator 50 (specifically, not from the front position RF1 of the right rectifying plate 110 but from the front position RF 2) irrespective of the other coolers.

In addition, a part of the air reaching the right first cutout 121 is guided to the cooling unit 90 side via the right corner 131. In this way, by supplying air from the portion (right corner 131) where both sides intersect in side view, a certain amount of air can be intensively guided to the cooling unit 90 side. In the present embodiment, the right corner 131 is provided in the vicinity of the fuel cooler 70 in a side view. In this way, more air can be taken in through the right corner 131 to efficiently cool the fuel cooler 70.

The air reaching the front end of the right rectifying plate 110 among the air guided forward is guided to the cooling unit 90 side via the front end. Specifically, the air that is guided to the cooling unit 90 side via the front end of the right rectifying plate 110 is guided forward of the range R2 of the lower side of the radiator 50. Here, another cooler (a condenser 80, an oil cooler 60, and a fuel cooler 70) is disposed in front of the range R2 below the radiator 50. Therefore, in front of the range R2 on the lower side of the radiator 50, air is guided from a position relatively far from the radiator 50 (specifically, not from the front position RF2 of the right rectifying plate 110 but from the front position RF 1).

As described above, the cooling unit 90 has a portion in which a plurality of coolers are arranged in the front-rear direction and a portion in which a plurality of coolers are not arranged (that is, the forefront cooler differs depending on a predetermined position as viewed from the front), and therefore, air can be guided forward of the forefront cooler through the right rectifying plate 110. That is, the air can be appropriately guided to all the coolers of the cooling unit 90 via two paths different from each other in the front-rear direction positions such as the right first cutout 121 and the front end of the right rectifying plate 110, and the coolers can be cooled effectively.

In addition, for example, air (air whose temperature has not risen) that has not passed through the condenser 80, the oil cooler 60, and the fuel cooler 70 can be supplied to the upper portion of the radiator 50, and therefore, the cooling efficiency of the radiator can be improved.

In addition, the air guided to the cooling unit 90 side through the right first cutout 121 does not pass through the condenser 80, the oil cooler 60, and the fuel cooler 70, and thus it is possible to suppress excessive air supply to these condensers 80 and the like. In this way, air can smoothly pass through the condenser 80 and the like.

Further, among the air guided forward, the air reaching the right second cutout 122 and the right third cutout 123 is guided to the cooling unit 90 side via the right second cutout 122 and the right third cutout 123. Here, as described above, the right second cutout 122 and the right third cutout 123 have straight-line edges with upper ends located at the rear and lower ends located at the front. That is, since the air is not guided through the corner portion formed to protrude at a right angle in a side view, for example, the air can be smoothly guided to the front of the cooling unit 90.

In addition, the right first notch 121 is open at the front and upper side. In this way, the right first cutout 121 can easily guide not only the lower air of the air taken in from the air hole 30 to the cooling unit 90, but also the air above the right rectifying plate 110 to the cooling unit 90 side via the right first cutout 121.

In addition, in the case where the shapes of the right rectifying plate 110 and the right vent hole 31 are compared with each other, the non-overlapping portion 31a of the right vent hole 31 is formed so as to cross the boundary portion between the right first cutout 121 and the right first portion 111 in the up-down direction in side view. In this way, the air sucked from the right vent hole 31 can be guided to the cooling unit 90 side without being guided by the right rectifying plate 110 (without passing through the right rectifying plate 110). In this way, the air can be guided to the cooling unit 90 side without passing through the right rectifying plate 110, and therefore the air can be easily guided to the center side of the cooling unit 90 in a plan view throughout the entire vertical direction of the cooling unit 90.

As described above, the air taken into the interior of the engine cover 10 by the cooling fan 40 is easily guided from the right cutout portion 120 (i.e., the portion having low intake resistance) of the right rectifying plate 110 to the cooling unit 90 side. That is, since it is possible to suppress all of the air taken into the interior of the engine cover 10 by the cooling fan 40 from passing through the condenser 80, the oil cooler 60, and the fuel cooler 70 (i.e., it is possible to reduce the amount of air passing through the condenser 80 or the like), it is possible to reduce the intake resistance of the entire cooling unit 90, and it is possible to increase the amount of air generated by the cooling fan 40. In this way, an appropriate air volume can be distributed to each cooler constituting the cooling unit 90 by the right cutout 120 of the right rectifying plate 110.

Further, of the air taken into the interior of the engine cover 10 through the left vent hole 32 by driving the cooling fan 40, the air that collides with the left flow straightening plate 150 is guided forward along the left flow straightening plate 150.

Then, similarly to the case of being guided forward along the right rectifying plate 110, the air guided forward is guided to the cooling unit 90 side through the cut-out portions (the left first cut-out portion 161, the left second cut-out portion 162, the left third cut-out portion 163, and the left fourth cut-out portion 164) and the tip end of the left rectifying plate 150. Note that, of the modes of guiding to the cooling unit 90 side via the left rectifying plate 150, the explanation is omitted in the substantially same way as the right rectifying plate 110.

As described above, the left rectifying plate 150 is formed in a stepped shape having a step difference that decreases as the left rectifying plate proceeds forward by the left first cutout 161 and the left second cutout 162, unlike the right rectifying plate 110. In this way, the air can be properly guided to all the coolers of the cooling unit 90 via three paths different from each other in the front-rear direction positions such as the left first cutout 161, the left second cutout 162, and the front end of the left rectifying plate 150, and the air can be cooled effectively in the coolers.

In the cooling unit 90, the condenser 80, the oil cooler 60, and the fuel cooler 70 are arranged so that the right side does not overlap in the front-rear direction and the left side overlaps in the front-rear direction in plan view. Here, in the rectifying plate 100, the entire size of the left cutout 160 of the left rectifying plate 150 is formed larger than the entire size of the right cutout 120 of the right rectifying plate 110. In this way, it is possible to guide relatively more air to the side that overlaps when viewed from the front, and guide relatively less air to the side that does not overlap. Further, it is possible to suppress excessive air supply to the condenser 80, the oil cooler 60, and the fuel cooler 70 (i.e., to reduce the amount of air passing through the condenser 80 or the like), and to improve the cooling efficiency.

Hereinafter, a structure for introducing oil into the oil cooler 60 and a structure for introducing oil from the oil cooler 60 (oil introducing/introducing structure) according to the present embodiment will be described with reference to fig. 4 and 14 to 25.

As shown in fig. 14 and 15, the oil introduction/discharge structure includes: inlet port 62 and outlet port 63 of oil cooler 60, oil outlet 200, oil circuit 300, and check valve 400.

As will be described later, in the oil outlet 200 and the oil circuit 300, a pipe (outlet pipe 210, etc.) is fixed to a joint portion (outlet first joint portion 231, etc.), but for convenience of explanation, a state before the pipe is fixed to the joint portion is shown in the drawings. In this way, in each drawing, illustration of each component is omitted or modified as appropriate for convenience of explanation.

The introduction port 62 of the oil cooler 60 shown in fig. 14 to 16 and the like is a portion that introduces oil into the oil cooler 60. The introduction port 62 is formed in a substantially cubic shape with its surfaces facing in the front-rear, up-down, left-right directions, respectively. The introduction port 62 is formed with a through hole penetrating in the left-right direction, and a screw thread is formed on the inner peripheral surface of the introduction port 62. The inlet port 62 is provided in the right lower portion of the oil cooler 60. More specifically, the inlet port 62 is fixed to an end portion of a pipe 61 provided in the oil cooler 60 so as to protrude rightward from a lower right portion, and communicates with the pipe 61.

The outlet port 63 of the oil cooler 60 shown in fig. 14 to 16 and the like is a portion that leads out oil from the oil cooler 60. The outlet port 63 is formed in a substantially cubic shape with its surfaces facing in the front-rear, up-down, left-right directions, respectively. The lead-out port 63 has a through hole penetrating in the left-right direction, and a screw thread is formed on the inner peripheral surface of the lead-out port 63. The outlet port 63 is provided in the upper right portion of the oil cooler 60. More specifically, the outlet port 63 is fixed to an end portion of a pipe 61 provided in the oil cooler 60 so as to protrude rightward from an upper right portion, and communicates with the pipe 61.

The oil outlet passage 200 shown in fig. 4, 14, 15, 17, and the like is a passage through which oil flows into the oil cooler 60. The downstream end portion (in the flow direction) of the oil outlet passage 200 is connected to the inlet port 62 of the oil cooler 60. The upstream end portion (in the flow direction) of the oil outlet passage 200 is connected to a control unit (not shown) of the power steering mechanism. A lower portion of the check valve 400 is connected to a connection portion (hereinafter referred to as a "first connection portion 510") of the oil outlet passage 200 to be connected to the introduction port 62. The oil outlet 200 includes an outlet pipe 210 and an outlet first joint 231.

The outward pipe 210 is a portion of the oil outward path 200 where the oil supply flows to the outward first joint 231. The forward pipe 210 is disposed substantially on the right side of the body frame 2 and extends in the front-rear direction. The outgoing pipe 210 is formed of a metal pipe (for example, a copper pipe) or the like between itself and a block joint 250 described later. The downstream end (front end) of the forward pipe 210 extends upward from below through the support base 21, and is inserted into the forward first joint 231.

The outlet first joint 231 connects the outlet pipe 210 to the inlet port 62 of the oil cooler 60. The forward first joint portion 231 includes a joint main body portion 235, a joint ring portion 236, and a joint nut portion 237.

The joint main body 235 constitutes a part of the first connection portion 510 (connection portion connected to the introduction port 62). The joint body 235 includes a joint body upper portion 241 and a joint body lower portion 242.

The joint main body upper part 241 constitutes an upper part of the joint main body part 235. The joint main body upper portion 241 is formed in a substantially rectangular parallelepiped shape with its surfaces facing in the front-rear, up-down, left-right directions, respectively. A joint body through hole 244 penetrating in the left-right direction is formed in the joint body upper part 241.

The joint body lower portion 242 constitutes a lower portion of the joint body portion 235. The joint main body lower portion 242 is formed in a substantially cylindrical shape with the cylinder center facing in the up-down direction. The joint main body lower part 242 is formed to extend downward from the bottom surface of the joint main body upper part 241. The joint body lower part 242 is integrally formed with the joint body upper part 241. The inside of the joint body lower part 242 communicates with the joint body through hole 244 of the joint body upper part 241. A screw thread is formed on the outer peripheral surface of the joint main body lower part 242. A step 245 facing downward is formed in a middle portion in the up-down direction of the inner peripheral surface of the joint main body lower portion 242. An inclined surface having an inner diameter gradually increasing as it goes downward is formed below the step 245 in the inner peripheral surface of the joint main body lower part 242.

The joint ring portion 236 is used to fix the outgoing pipe 210 to the joint body portion 235 together with a joint nut portion 237 described later. The joint ring 236 is formed in a substantially cylindrical shape with the cylinder center facing in the up-down direction. The outer peripheral surface of the joint ring 236 is formed as an inclined surface having an outer diameter gradually decreasing as it goes upward.

The joint nut 237 is used to fix the outgoing pipe 210 to the joint body 235 together with the joint ring 236. The joint nut portion 237 is formed in a substantially hexagonal nut shape with its axial center oriented in the up-down direction. A screw thread is formed on the inner peripheral surface of the joint nut portion 237. A bottom surface portion 246 having a smaller inner diameter in the up-down direction than the other portion is formed at the lower end portion of the joint nut portion 237. In this way, the joint nut portion 237 is formed in a bottomed tubular shape with a part of the bottom surface open.

In the forward first joint portion 231 having the above-described configuration, the forward pipe 210 is fixed to the joint main body portion 235 by the joint ring portion 236 and the joint nut portion 237. A specific mode of fixing the forward pipe 210 to the joint body 235 will be described below.

First, the outlet pipe 210 is inserted into the joint main body 235 with the joint nut 237 and the joint ring 236 inserted. The tip of the forward pipe 210 is in contact with a stepped portion 245 formed inside the joint body 235 in the vertical direction. This restricts upward relative movement of the forward pipe 210 with respect to the joint main body 235.

In this state, the forward pipe 210 is not fixed to the joint body 235. Accordingly, the forward pipe 210 is movable relative to the joint main body 235 (except upward as described above). Specifically, the forward pipe 210 can move downward relative to the joint body 235. The outlet pipe 210 is rotatable (movable) about the axis of the outlet pipe 210 with respect to the joint body 235.

From this state, the joint nut 237 moves upward, and the inner peripheral surface of the joint nut 237 is screwed with the joint body lower part 242 of the joint body 235. As described above, when the joint nut 237 is screwed and moved further upward, the bottom surface 246 of the joint nut 237 contacts the joint ring 236 from below, and the joint ring 236 is pushed Fang Tuiqi from below. When the joint ring 236 is pushed up, the inclined surface of the joint body lower portion 242 of the joint body 235 slides against the inclined surface of the joint ring 236, and the joint ring 236 is deformed so as to gradually decrease in diameter.

When the inner peripheral surface of the joint ring portion 236 is deformed so as to be reduced in diameter, the inner peripheral surface of the joint ring portion 236 bites into the outer peripheral surface of the forward pipe 210. When the inner peripheral surface of the joint ring portion 236 bites into the outer peripheral surface of the forward pipe 210, the screw engagement of the joint nut portion 237 is completed. As described above, when the inner peripheral surface of the joint ring 236 bites into the outer peripheral surface of the forward pipe 210, the forward pipe 210 is restricted from moving relatively to the joint body 235, such as upward, downward, or rotation about the axial center (see fig. 17 (b)). In this way, the outgoing pipe 210 is fixed to the joint body 235.

The oil circuit 300 shown in fig. 4, 14 to 16, and the like is a passage through which the oil flows out from the oil cooler 60. The upstream end of the oil circuit 300 is connected to the outlet port 63 of the oil cooler 60. The downstream end of the oil circuit 300 is connected to the transmission mechanism accommodated in the transmission case 6. Further, an upper portion of the check valve 400 is connected to a connection portion (hereinafter referred to as "second connection portion 520") of the oil circuit 300 to be connected to the outlet port 63. The oil circuit 300 includes a circuit pipe 310 and a circuit joint 331.

The circuit pipe 310 is a portion in the oil circuit 300 into which the oil flows from the circuit joint 331. As shown in fig. 4, an upstream end (front end) of the circuit pipe 310 extends downward from the inside of the circuit joint 331, and is bent downward and extends rearward below the support base 21. The circuit pipe 310 is disposed substantially on the right side of the body frame 2 and is formed to extend in the front-rear direction. The circuit piping 310 is formed of a metal piping (e.g., copper pipe).

The circuit joint 331 connects the circuit pipe 310 to the outlet port 63 of the oil cooler 60.

The circuit joint portion 331 constitutes a part of the second connection portion 520 (connection portion connected to the lead-out port 63). The circuit joint portion 331 includes a joint upper portion 341 formed at an upper end portion and a joint lower portion 343 extending downward from the joint upper portion 341.

The joint upper portion 341 is formed to have a flat surface on the right and left sides. A joint body through hole 345 (see fig. 21) that penetrates in the left-right direction is formed in the joint upper portion 341.

The joint lower portion 343 is formed of a metal pipe. The joint lower portion 343 is formed in a substantially tubular shape elongated in the up-down direction and bent at a middle portion in the up-down direction. In more detail, the joint lower part 343 is formed of: a portion extending straight downward from the lower surface of the joint upper portion 341, a portion extending straight downward from the portion to the right, and a portion extending straight downward from the portion. In this way, the joint lower portion 343 is formed so as to bypass the forward first joint portion 231 of the adjacent forward pipe 210.

A predetermined tubular member is disposed at the lower end of the joint lower portion 343. The circuit pipe 310 and the circuit joint 331 are connected to each other by the cylindrical member using a joint ring portion 336 and a joint nut portion 337, which are configured similarly to the joint ring portion 236 and the joint nut portion 237 of the outgoing pipe 210.

The check valve 400 shown in fig. 14 to 20 is used in the following cases: when the hydraulic pressure of the oil flowing to the oil cooler 60 is higher than a predetermined hydraulic pressure, the check valve 400 bypasses the inlet port 62 without introducing the oil to the inlet port 62 of the oil cooler 60. The check valve 400 is formed in a long shape along the up-down direction. The check valve 400 includes a plurality of substantially cylindrical members configured to allow oil to flow therethrough. Specifically, as shown in fig. 18 to 20, the check valve 400 includes a lower member 410, an upper member 420, and an intermediate member 430. Further, as a member provided inside the intermediate member 430, the check valve 400 includes: an upper O-ring 451, a lower O-ring 452, a retainer 453, a restriction cylinder 454, a valve spool 455, and a spring 456.

The lower member 410 constitutes a lower portion (lower side) of the check valve 400. The lower member 410 includes a lower head 411 and a lower tube 412.

The lower head 411 constitutes the lower portion of the lower member 410. The lower head 411 is formed in a substantially rectangular parallelepiped shape having surfaces facing in the front-rear, upper-lower, left-right directions, respectively. A lower head through hole 414 is formed in the lower head 411 so as to penetrate in the left-right direction. As will be described later, the lower head 411 is connected to a first connection portion 510.

The lower cylinder 412 constitutes an upper portion of the lower member 410. The lower tube portion 412 is formed in a substantially tubular shape with the center of the tube facing in the up-down direction. The lower tube portion 412 is formed to extend upward from the upper surface of the lower head portion 411. The lower cylindrical portion 412 is integrally formed with the lower head portion 411. The inner side of the lower tube portion 412 communicates with a lower head through hole 414 of the lower head. The lower tube portion 412 is formed with a lower tube portion reduced diameter portion 415, and the lower tube portion reduced diameter portion 415 is formed by reducing the outer diameter within a predetermined range in the up-down direction including the upper end of the lower tube portion 412.

The upper member 420 constitutes an upper portion (upper side) of the check valve 400. The upper member 420 includes an upper head 421 and an upper tube 422.

The upper head 421 constitutes an upper portion of the upper member 420. The upper head 421 is formed in a substantially rectangular parallelepiped shape having surfaces facing in the front-rear, upper-lower, left-right directions, respectively. An upper head through hole 424 is formed in the upper head 421 so as to penetrate in the left-right direction. As will be described later, the upper head 421 is connected to the second connection portion 520.

The upper cylinder 422 constitutes a lower portion of the upper member 420. The upper tube 422 is formed in a substantially tubular shape with the center of the tube facing in the up-down direction. The upper tube 422 is formed to extend downward from the lower surface of the upper head 421. The upper cylinder 422 is integrally formed with the upper head 421. The inside of the upper tube 422 communicates with the upper head through hole 424 of the upper head 421. An upper tube portion reduced diameter portion 425 is formed in the upper tube portion 422, and the upper tube portion reduced diameter portion 425 is formed by reducing the outer diameter in a predetermined range in the up-down direction including the lower end of the upper tube portion 422.

The middle part 430 is disposed between the lower part 410 and the upper part 420. The intermediate member 430 is connected to the lower member 410 and the upper member 420, respectively. The intermediate member 430 is formed in a substantially cylindrical shape with the cylinder center facing in the up-down direction. The intermediate member 430 includes an intermediate through hole 431.

The intermediate through hole 431 is a hole penetrating in the up-down direction of the intermediate member 430. The intermediate through hole 431 is formed to communicate the upper surface and the lower surface of the intermediate member 430. An upper cylindrical portion reduced diameter portion 425 of the upper member 420 is inserted into an upper end portion of the intermediate through hole 431. A lower cylindrical portion reduced diameter portion 415 of the lower member 410 is inserted into a lower end portion of the intermediate through hole 431. In this way, the intermediate member 430 is formed so as to overlap with the upper member 420 and the lower member 410 (members adjacent to each other) at positions in the up-down direction (longitudinal direction).

As shown in fig. 19, the intermediate through hole 431 includes an intermediate reduced diameter portion 432, an intermediate first recess 433, an intermediate second recess 434, and an intermediate third recess 435.

The intermediate reduced diameter portion 432 is formed slightly below the central portion in the up-down direction of the intermediate through hole 431. The intermediate reduced diameter portion 432 is formed so that the inner diameter is smaller than the other portions over a predetermined range in the up-down direction. The intermediate reduced diameter portion 432 is configured to be capable of abutting against a valve body 455 described later as a so-called valve seat.

The intermediate first recess 433 is formed near the upper end of the intermediate through hole 431. The inner peripheral surface of the intermediate through hole 431 is recessed radially outward to form an intermediate first recess 433.

The intermediate second recess 434 is formed near the lower end of the intermediate through hole 431. The inner peripheral surface of the intermediate through hole 431 is recessed radially outward to form an intermediate second recess 434.

The intermediate third recess 435 is formed slightly above the central portion of the intermediate through hole 431 in the vertical direction. In other words, the intermediate third recess 435 is formed between the intermediate reduced diameter portion 432 and the intermediate first recess 433. The inner peripheral surface of the intermediate through hole 431 is recessed radially outward to form an intermediate third recess 435.

The upper O-ring 451 is formed in a circular shape in plan view and is elastically deformable. The upper O-ring 451 is fitted in the first recess 433 of the intermediate through hole 431. The upper O-ring 451 is disposed in a state compressed between the inner peripheral surface of the intermediate through hole 431 and the outer peripheral surface of the upper tubular portion reduced diameter portion 425 of the upper member 420 (a state in which elastic deformation occurs). In this way, the upper O-ring 451 blocks the intermediate through hole 431 from the upper tubular portion reduced diameter portion 425, and restricts communication between the intermediate through hole 431 and the upper tubular portion reduced diameter portion 425.

The lower O-ring 452 is formed in an annular shape and is elastically deformable. The lower O-ring 452 is fitted into the second intermediate recess 434 of the intermediate through hole 431. The lower O-ring 452 is provided in a state compressed between the inner peripheral surface of the intermediate through hole 431 and the outer peripheral surface of the lower cylindrical portion reduced diameter portion 415 of the lower member 410 (a state in which elastic deformation occurs). In this way, the lower O-ring 452 blocks the space between the intermediate through hole 431 and the lower cylindrical portion reduced diameter portion 415, and restricts communication between the intermediate through hole 431 and the lower cylindrical portion reduced diameter portion 415.

The collar 453 has a substantially C-shape in a plan view. The collar 453 is fitted into the intermediate third recess 435 of the intermediate through hole 431.

The regulating cylinder portion 454 is formed in a substantially cylindrical shape with the cylinder center facing in the up-down direction. The upper end of the restriction cylinder portion 454 is formed in a flange shape extending radially inward. The regulating cylinder 454 is housed inside the intermediate through hole 431. A stopper 453 is disposed above the restriction cylinder 454, and upward movement of the restriction cylinder 454 is restricted.

The valve spool 455 is formed in a substantially cylindrical shape (bottomed cylindrical shape) with the cylinder center facing in the up-down direction. Specifically, a valve body through hole 459 that communicates the outer peripheral surface of the valve body 455 with the upper surface is formed inside the valve body 455. The lower surface of the valve core 455 is formed in a bulged shape with a radially central portion bulged downward. The valve member 455 is housed inside the intermediate through hole 431.

The spring 456 is a compression spring formed by shaping a metal wire into a spiral shape (coil shape). The spring 456 is disposed between the regulating cylinder 454 (more specifically, a flange-like portion at the upper end of the regulating cylinder 454) and the valve member 455 in a state in which the expansion and contraction direction is oriented in the up-down direction and compressed. Thus, the spring 456 biases the valve spool 455 in a direction away from the restriction cylinder 454 (in which upward movement is restricted), that is, downward.

With the above-described structure, in the check valve 400, when the valve body 455 is brought into contact with the intermediate reduced diameter portion 432 (valve seat) by the urging force of the spring 456, communication in the up-down direction is restricted at the intermediate portion in the up-down direction of the intermediate member 430, and the oil flow from the lower member 410 side to the upper member 420 side is prohibited (hereinafter referred to as "closed state").

In the closed state, when the hydraulic pressure of the oil on the lower member 410 side is higher than the predetermined hydraulic pressure, more specifically, when the oil is raised to a level that is against the urging force of the spring 456, the valve spool 455 is pushed upward by the oil, as shown in fig. 20. In this way, when the valve member 455 is pushed upward, the valve member 455 is separated from the intermediate reduced diameter portion 432 (valve seat), and therefore the intermediate portion in the up-down direction of the intermediate member 430 is communicated in the up-down direction. Thereby, the check valve 400 is in a state (hereinafter referred to as "open state") in which the flow of oil from the lower member 410 side to the upper member 420 side is permitted.

In the check valve 400, the upper O-ring 451, the lower O-ring 452, the retainer 453, the restriction cylinder 454, the valve spool 455, the spring 456, and the intermediate reduced diameter portion 432 (valve seat) are disposed in the intermediate member 430 among the plurality of substantially cylindrical members (the lower member 410, the upper member 420, and the intermediate member 430). This allows the main structure of the check valve 400 to be integrated into one component (intermediate member 430), which reduces the labor required for assembly and simplifies the overall structure of the check valve 400.

The structure of the first connection portion 510 will be described in detail below with reference to fig. 14 to 16, 21, and 22.

As described above, the first connection portion 510 is a portion connecting the oil outlet passage 200 and the inlet port 62 of the oil cooler 60, and the lower portion (lower member 410) of the check valve 400 is also connected in the same manner. In the first connection portion 510, the oil outlet passage 200, the introduction port 62 of the oil cooler 60, and the lower member 410 of the check valve 400 are connected using the first bolt 511.

First bolt 511 shown in fig. 21 and 22 is a banjo bolt. The first bolt 511 includes a first head 512, a first shaft 513, a first shaft hole 514, a first right through hole 515, and a first left through hole 516.

The first header 512 is a portion formed in a hexagonal shape. The first shaft portion 513 is a portion formed so as to extend leftward from the first head portion 512. A screw is formed on the outer peripheral surface of the first shaft portion 513. The first shaft hole 514 extends from the vicinity of the first head 512 toward the distal end side (leftward) in the first shaft portion 513, and opens at the distal end. The first right through hole 515 is a hole formed to penetrate in the front-rear direction (radial direction) near the first head portion 512 of the first shaft portion 513. The first left through hole 516 is a hole formed in the left and right central portions of the first shaft portion 513 so as to penetrate in the front-rear direction (radial direction). The first shaft hole 514, the first right through hole 515, and the first left through hole 516 communicate with each other.

In the first connection portion 510, a first bolt 511 is inserted from the right to the left through a joint main body through hole 244 of the oil outlet passage 200 and a lower head through hole 414 of the check valve 400, and a tip end portion of the first bolt 511 is screwed with an introduction port 62 of the oil cooler 60. As shown in fig. 22, gaskets 531 are disposed between the first bolts 511 and the forward first joint 231 of the forward pipe 210, between the forward first joint 231 of the oil forward 200 and the lower member 410 of the check valve 400, and between the lower member 410 of the check valve 400 and the introduction port 62, respectively.

The first right through hole 515 of the first bolt 511 is disposed inside the joint body through hole 244 of the outgoing first joint part 231. The first left through hole 516 of the first bolt 511 is disposed inside the lower head through hole 414 of the lower member 410 of the check valve 400.

In this way, in the first connection portion 510, the oil outlet passage 200, the lower portion (lower member 410) of the check valve 400, and the introduction port 62 of the oil cooler 60 are connected in a mutually communicating state via the first bolt 511.

As described above, in the first connecting portion 510, the first bolt 511 is screwed into the introduction port 62 from the state where the first bolt 511 is inserted into the joint main body through hole 244 of the oil outlet passage 200 and the lower head through hole 414 of the check valve 400, thereby fixing the oil outlet passage 200, the check valve 400, and the introduction port 62 to each other.

That is, for example, if the first bolt 511 is screwed, the oil passage 200 is provided so as to be swingable in the front-rear direction via the first bolt 511. In the oil outlet 200, if the outlet pipe 210 is fixed to the joint main body 235, the outlet pipe 210 is provided rotatably around the axis with respect to the joint main body 235 as described above. In this way, since the forward/backward swing and the rotation about the axial center can be performed in various ways on the forward/backward swing pipe 210 during assembly, the assembly and workability can be improved, and the stress during installation can be eliminated.

The oil outlet passage 200 is disposed to extend downward from the first connection portion 510. That is, the lower end portion of the oil outlet passage 200 is disposed so that the longitudinal direction is oriented in the up-down direction and extends downward from the check valve 400. In this way, since the plurality of elongated members are arranged substantially vertically in the right direction of the oil cooler 60, the space in the right direction of the oil cooler 60 can be effectively utilized, and space saving can be achieved.

The structure of the second connection portion 520 will be described in detail below with reference to fig. 14 to 16, 21, and 22.

As described above, the second connection portion 520 is a portion connecting the oil circuit 300 to the outlet port 63 of the oil cooler 60, and the upper portion (upper member 420) of the check valve 400 is also connected in the same manner. In the second connection 520, the oil circuit 300, the outlet port 63 of the oil cooler 60, and the upper member 420 of the check valve 400 are connected using a second bolt 521.

The second bolt 521 has the same structure as the first bolt 511. Specifically, the second head portion 522, the second shaft portion 523, the second shaft hole 524, the second right through hole 525, and the second left through hole 526 of the second bolt 521 are members corresponding to the first head portion 512, the first shaft portion 513, the first shaft hole 514, the first right through hole 515, and the first left through hole 516 of the first bolt 511, respectively.

In the second connection portion 520, a second bolt 521 is inserted from the right to the left through a joint main body through hole 345 of the oil circuit 300 and an upper head through hole 424 of the check valve 400, and a tip end portion of the second bolt 521 is screwed with the outlet port 63 of the oil cooler 60. As shown in fig. 22, gaskets 531 are disposed between the second bolt 521 and the circuit joint portion 331 of the oil circuit 300, between the circuit joint portion 331 of the oil circuit 300 and the upper member 420 of the check valve 400, and between the upper member 420 of the check valve 400 and the outlet port 63, respectively.

The second right through hole 525 of the second bolt 521 is disposed inside the joint upper portion 341 of the oil circuit 300. The second left through hole 526 of the second bolt 521 is disposed inside the upper member 420 of the check valve 400.

In this way, in the second connection portion 520, the oil circuit 300, the upper portion (upper side member 420) of the check valve 400, and the outlet port 63 of the oil cooler 60 are connected in a mutually communicating state via the second bolt 521.

As described above, the check valve 400 is disposed with the first connection portion 510 and the second connection portion 520 oriented in the longitudinal direction in the up-down direction. As shown in fig. 16, the check valve 400 is disposed at the same position as the oil cooler 60 in the front-rear direction position. That is, the check valve 400 is disposed so as to substantially overlap the oil cooler 60 in a side view and not to protrude forward or backward of the oil cooler 60. This makes it possible to effectively use the space on the right side of the oil cooler 60 and to save space. Further, since the check valve 400 can be disposed in the vicinity of the oil cooler 60, the response speed of the check valve 400 can be improved.

In addition, at the time of assembly, before the second bolt 521 is inserted into the second connection portion 520, the check valve 400 is provided so as to be swingable in the front-rear direction via the first bolt 511 of the first connection portion 510. In addition, before the first bolt 511 is inserted into the first connection portion 510, the check valve 400 is provided so as to be swingable in the front-rear direction via the second bolt 521 of the second connection portion 520. In this way, even when one of the first bolt 511 and the second bolt 521 is inserted first, the check valve 400 swings freely in the front-rear direction if the other is not inserted, and therefore, the assembling property and the workability can be improved.

In addition, when the check valve 400 is assembled, the up-down direction positions of the upper and lower ends of the check valve 400 are determined according to the first and second connection portions 510 and 520. Therefore, it is also considered that relatively precise accuracy is required for the vertical positions of the upper and lower ends of the check valve 400 (i.e., the length of the check valve 400 in the longitudinal direction).

However, as described above, in the check valve 400, the intermediate member 430 is formed so as to overlap each other in the upper end portion and the lower end portion with the upper member 420 and the lower member 410 (members adjacent to each other) in the up-down direction position. The intermediate member 430, the upper member 420, and the lower member 410 are not fixed to each other by, for example, screws (fixing means). That is, since the intermediate member 430, the upper member 420, and the lower member 410 are configured to be movable relative to each other via the upper O-ring 451 and the lower O-ring 452, the length (the total length) of the check valve 400 in the longitudinal direction can be arbitrarily changed.

Specifically, as shown in fig. 23, for example, when the entire length of the check valve 400 is to be extended, the upper member 420 and the lower member 410 are pulled in a direction away from the intermediate member 430. Accordingly, the upper member 420 and the lower member 410 move upward and downward while sliding with the upper O-ring 451 and the lower O-ring 452 of the intermediate member 430, respectively, and the entire length of the check valve 400 is changed to be long. For example, when the entire length of check valve 400 is to be shortened, upper member 420 and lower member 410 are pushed in a direction approaching intermediate member 430. Accordingly, the upper member 420 and the lower member 410 move downward and upward while sliding with the upper O-ring 451 and the lower O-ring 452 of the intermediate member 430, respectively, and the entire length of the check valve 400 is changed to be short.

In this way, when the check valve 400 is assembled as described above, the vertical positions of the upper end and the lower end of the check valve 400 are determined by the first connecting portion 510 and the second connecting portion 520, but the entire length of the check valve 400 can be arbitrarily changed, so that the assembling property and the workability can be improved.

The way in which oil flows through the oil introduction/discharge structure configured as described above will be described below with reference to fig. 24 and 25.

First, as shown in fig. 24, it is assumed that the check valve 400 is in a closed state. In this case, the oil flowing in the oil outlet 200 is introduced into the first shaft hole 514 from the outlet first joint 231 of the outlet pipe 210 through the first right through hole 515 of the first bolt 511. The oil introduced into the first shaft hole 514 flows toward the tip end side in the first shaft hole 514. Then, the oil is introduced from the opening of the tip end of the first bolt 511 into the introduction port 62 of the oil cooler 60.

The oil guided from the guide port 63 of the oil cooler 60 is guided into the second shaft hole 524 through the opening at the tip end of the second bolt 521. The oil introduced into the second shaft hole 524 flows toward the second head 522 side in the second shaft hole 524. Then, the oil is introduced into the oil circuit 300 through the second right through hole 525.

Here, the first shaft hole 514 of the first bolt 511 communicates with the lower member 410 of the check valve 400 via the first left through hole 516, focusing on the oil flowing to the inlet port 62 of the oil cooler 60. However, as described above, since the check valve 400 is closed and the oil flow from the lower member 410 to the upper member 420 is inhibited, the oil flowing through the first shaft hole 514 of the first bolt 511 is not led to the upper member 420, and is led to the oil cooler 60 in its entirety.

In contrast, when the hydraulic pressure of the oil on the lower member 410 side of the check valve 400 is higher than the predetermined hydraulic pressure, the valve spool 455 is pushed upward, and the check valve 400 changes from the closed state to the open state as shown in fig. 23. In this way, when the check valve 400 is in the open state, the oil is allowed to flow from the lower member 410 to the upper member 420.

In this case, a part of the oil flowing through the first shaft hole 514 of the first bolt 511 is introduced into the lower member 410 of the check valve 400 via the first left through hole 516, and flows toward the upper member 420. The oil flowing to the upper member 420 is introduced into the second shaft hole 524 through the second left through hole 526 of the second bolt 521. Then, the oil introduced into the second shaft hole 524 flows toward the second head 522 side in the second shaft hole 524. Then, the oil is introduced into the oil circuit 300 through the second right through hole 525.

In this way, in the oil introduction/discharge structure, by using the check valve 400, oil can be prevented from being introduced into the introduction port 62 of the oil cooler 60 and bypass the introduction port 62 according to the hydraulic pressure of the oil on the lower member 410 side of the check valve 400. In this way, excessive pressure applied to the oil cooler 60 is suppressed by the check valve 400, and occurrence of defects such as breakage of the oil cooler 60 can be suppressed.

The structure of block joint 250 according to the present embodiment will be described in detail below with reference to fig. 3 and 26 to 31.

As described above, the block joint 250 is provided in the middle of the oil outlet passage 200 of the control unit that connects the oil cooler 60 and the power steering mechanism. The block joint 250 shown in fig. 26 and 27 includes a block main body 251, a first block opening 252, a second block opening 253, and a block through hole 254.

The block main body 251 is a main structure of the block joint 250. The block main body portion 251 is formed of a substantially hexahedron (substantially polyhedron). The block main body portion 251 includes: an upper surface 261 having a surface facing generally upward, a lower surface 262 having a surface facing generally downward, a left surface 263 having a surface facing generally leftward, a right surface 264 having a surface facing generally rightward, a front surface 265 having a surface facing forward, and a rear surface 266 having a surface facing rearward. The left surface 263 and the right surface 264 are formed in a substantially square shape. In addition, the upper surface 261, the lower surface 262, the front surface 265, and the rear surface 266 are formed in a substantially rectangular shape.

The first block opening 252 is an opening formed in the front surface 265 of the block main body 251. The first block opening 252 is a perfect circle opening. The first block opening 252 is formed in a vicinity portion of the lower surface 262 in the front surface 265. The diameter of the first block opening 252 is approximately half the length of the front surface 265 in the longitudinal direction (the length of the upper surface 261 in the opposite direction to the lower surface 262) and approximately 3/4 the length of the front surface 265 in the short side direction (the length of the right surface 264 in the opposite direction to the left surface 263).

The second block opening 253 is an opening formed in the upper surface 261 of the block main body 251. That is, the second block opening 253 is formed on a surface adjacent to the front surface 265 on which the first block opening 252 is formed. The second block opening 253 is open in a perfect circle. The second block opening 253 is formed in the vicinity of the right surface 264 and the rear surface 266 in the upper surface 261. The diameter of the second block opening 253 is formed to be approximately about half of the length of the upper surface 261 in the longitudinal direction (length of the front surface 265 and the rear surface 266 in the opposite direction) and approximately 3/4 of the length of the upper surface 261 in the short side direction (length of the right surface 264 and the left surface 263 in the opposite direction).

The block through hole 254 is a hole formed in the block body 251. The block through hole 254 is formed to connect the first block opening 252 and the second block opening 253. More specifically, the block through hole 254 is formed by intersecting a portion formed to extend straight from the first block opening 252 toward the rear surface 266 side and a portion formed to extend straight from the second block opening 253 toward the lower surface 262 side. Thus, the block through-hole 254 is formed in a substantially L-shape as a whole. Further, screw threads are formed on inner peripheral surfaces of the block through-hole 254 in the vicinity of the first block opening 252 and the second block opening 253, respectively.

The block joint 250 configured as described above is fixed to the flywheel housing 4 via the bracket 270.

First, the structure of the flywheel housing 4 will be described with reference to fig. 3, 28, and 30.

The flywheel housing 4 covers a flywheel, not shown. The flywheel housing 4 is formed in a substantially disc shape having a hollow shape with a thickness in the front-rear direction, and is formed relatively large so as to extend across the left-right direction of the vehicle body. The flywheel housing 4 is formed in a substantially circular shape except for a lower end portion when viewed from the front. The flywheel housing 4 includes a mount 23 to which a hood support member 24 is mounted. The hood support member 24 is as follows: the rear part of the hood 10 is rotatably supported and is erected upward from the mount 23.

The mounting tables 23 are provided on the left and right sides of the flywheel housing 4, respectively. Note that, of the left and right mounting tables 23, the description will be given focusing on the right mounting table 23, and the description of the left mounting table 23 will be omitted. Hereinafter, unless otherwise specified, the right mount 23 will be simply referred to as "mount 23".

The mount 23 is formed at the upper right portion of the flywheel housing 4. More specifically, the mount 23 is formed at a circumferential intermediate portion between the upper end 4a and the right end 4b of the outer peripheral portion of the flywheel housing 4. The mounting table 23 is formed in a convex shape protruding upward. Thus, the mount 23 is formed to protrude upward from the upper right portion of the flywheel housing 4. A substantially horizontal surface is formed at the upper end (convex upper surface side) of the mounting table 23. The upper end of the mounting table 23 is formed at a position lower than the upper end 4a of the flywheel housing 4.

Thus, the entire mounting table 23 is disposed in the following region: a region surrounded by a first virtual line L1 extending rightward from the upper end 4a of the flywheel housing 4 and a second virtual line L2 extending upward from the right end 4b of the flywheel housing 4 when viewed from the front. That is, the mount 23 is formed to be located inside the flywheel housing 4 in the up-down-left-right direction.

Next, a structure of the bracket 270 and a structure of fixing the block joint 250 to the flywheel housing 4 via the bracket 270 will be described.

The bracket 270 shown in fig. 26 and 27 is a member for fixing the block joint 250 to the flywheel housing 4. The bracket 270 is formed in a substantially elongated plate shape made of metal. The bracket 270 includes a bracket fixing portion 271, a bent portion 272, and a joint fixing portion 273.

The bracket fixing portion 271 is a portion for fixing the bracket 270 to the flywheel housing 4. As shown in fig. 28 and 31, the bracket fixing portion 271 is disposed so as to contact the rear end portion of the upper end of the mount 23 with the plate surface facing in the up-down direction. The bracket fixing portion 271 is fixed to the upper end of the mounting table 23 via a bolt.

The bent portion 272 is a portion where the bracket 270 is bent. The bent portion 272 forms a portion of the bracket 270 other than the bracket fixing portion 271 so that the plate faces upward and downward and extends downward and rightward from the bracket fixing portion 271.

The joint fixing portion 273 is a portion for fixing the block joint 250. The joint fixing portion 273 is formed at a right lower end of the bracket 270. The joint fixing portion 273 is configured to contact the left surface 263 of the block joint 250. In this way, the block joint 250 is fixed to the joint fixing portion 273 by welding or the like.

In this way, the block joint 250 is fixed in a state separated from the flywheel housing 4 via the bracket 270. The block joint 250 is formed to have substantially the same vertical position as the bottom surface of the cab 12 (see fig. 30).

As shown in fig. 31, the block joint 250 fixed as described above is disposed in the following region as in the whole of the mounting table 23: a region surrounded by a first virtual line L1 extending rightward from the upper end 4a of the flywheel housing 4 and a second virtual line L2 extending upward from the right end 4b of the flywheel housing 4 when viewed from the front. That is, the block joint 250 is formed to be located inside the flywheel housing 4 in the up-down-left-right direction.

As described above, the block joint 250 is provided in the middle of the oil outlet passage 200 of the control unit that connects the oil cooler 60 and the power steering mechanism. More specifically, the block joint 250 is provided between the forward upstream side pipe 211 and the forward downstream side pipe 212 in the forward pipe 210, which is a portion into which the oil of the oil supply forward path 200 flows, and the forward upstream side pipe 211 is located on the control unit side (upstream side) and the forward downstream side pipe 212 is located on the oil cooler 60 side (downstream side), and the block joint 250 connects these pipes in a mutually communicating state.

The upstream piping 211 is a flexible rubber piping. The upstream pipe 211 extends from above the flywheel housing 4 toward the flywheel housing 4. The downstream end portion of the forward upstream pipe 211 (i.e., the end portion on the block joint 250 side) extends above the bracket 270 in the extending direction (lower right) of the bracket 270 (in a substantially parallel manner). A downstream end portion of the forward upstream pipe 211 is provided with a forward second joint 232.

The outgoing second joint 232 is formed in a substantially cylindrical shape. The forward second joint 232 is fixed with the downstream end of the forward upstream pipe 211 inserted therein. A screw is formed on the outer peripheral surface of the outgoing second joint part 232.

The downstream piping 212 is a metal piping (at least, it is not flexible as compared with the upstream piping 211). The downstream pipe 212 has an upstream end (i.e., an end on the block joint 250 side) provided with a downstream third joint portion 233.

The outgoing third joint portion 233 is formed in a substantially cylindrical shape. The forward third joint 233 is fixed with the upstream end of the forward downstream pipe 212 inserted therein. A screw thread is formed on the outer peripheral surface of the outgoing third joint part 233.

The outgoing second joint part 232 configured as described above is screwed into the second block opening 253 of the block joint 250. In this way, the forward upstream piping 211 is connected (fixed) to the block joint 250. The outgoing third joint part 233 is screwed into the first block opening 252 of the block joint 250. In this way, the forward downstream pipe 212 is connected (fixed) to the block joint 250.

Thus, the block joint 250 connects the upstream downstream pipe 212 and the upstream downstream pipe 211 in communication with each other at the middle portion of the oil outlet 200.

In this way, the block joint 250 connects the upstream pipe 211 and the downstream pipe 212 to surfaces (the front surface 265 and the upper surface 261) adjacent to each other at the middle portion of the oil outlet 200. This makes it possible to set a predetermined angle (90 degrees in the present embodiment) in the middle of the oil outlet passage 200 with a simple configuration.

In the present embodiment, the forward upstream pipe 211 is a pipe made of rubber, whereas the forward downstream pipe 212 is a pipe made of metal. In this way, the pipes having different flexibility can be easily connected via the block joint 250, and thus the degree of freedom in design can be improved. That is, the upstream-side piping 211 and the downstream-side piping 212 can be appropriately selected and used according to the arrangement place, the application, and the like where the piping is provided. For example, if the downstream piping 212 is used, the strength, the vibration resistance, and the durability can be improved. In addition, if the upstream piping 211 is used, the cost can be reduced and the assembly can be facilitated.

The block joint 250 is fixed to the flywheel housing 4 via a bracket 270. In this way, the flywheel housing 4 having relatively high rigidity can be used to improve the degree of freedom in design.

As described above, the downstream end portion of the forward upstream pipe 211 extends above the bracket 270 in the extending direction of the bracket 270. Thereby, space saving can be achieved. Further, by disposing the metal bracket 270 along the forward upstream piping 211 as the rubber piping, the forward upstream piping 211 can be protected.

The block joint 250 is fixed in a state separated from the flywheel housing 4 via a bracket 270. That is, since the connection portion between the forward upstream pipe 211 and the forward downstream pipe 212 is separated from the vehicle body including the flywheel housing 4, the influence of the vibration of the vehicle body on the connection portion (block joint 250) between the forward upstream pipe 211 and the forward downstream pipe 212 can be reduced. In particular, in the present embodiment, since the bracket fixing portion 271 of the bracket 270 is fixed with the plate surface facing in the up-down direction, the vibration in the up-down direction of the vehicle body can be effectively absorbed, and the influence on the block joint 250 can be effectively reduced.

The bracket 270 is fixed to the mount 23 of the flywheel housing 4, which has a substantially horizontal surface formed at the upper end (convex upper surface side). In this way, a place where the flywheel housing 4 is a large member having a substantially disk shape and is relatively difficult to use effectively, that is, a place near the flywheel housing 4 can be used effectively. The mounting table 23 is a member to which the hood support member 24 is attached. In this way, since the block joint 250 is fixed using a portion that is used for other purposes in the flywheel housing 4, the structure can be simplified and the vicinity of the flywheel housing 4 can be effectively utilized.

The block joint 250 is formed to be located inside the flywheel housing 4 in the up-down-left-right direction. This can effectively utilize the vicinity of the flywheel housing 4.

As described above, the tractor 1 (work vehicle) according to the present embodiment includes:

a hood 10 having ventilation holes 30 on left and right sides of the hood 10;

a cooling fan 40 provided inside the engine cover 10, the cooling fan 40 taking in air outside the engine cover 10 into the inside via the ventilation hole 30;

a cooling unit 90 provided in front of the cooling fan 40 in the engine cover 10, the cooling unit 90 cooling a fluid to be cooled by air taken in by the cooling fan 40; and

a pair of rectifying plates 100 (right rectifying plate 110, left rectifying plate 150), the pair of rectifying plates 100 being provided between the ventilation hole 30 and the cooling unit 90 in the hood 10, and the pair of rectifying plates 100 having a cutout portion (right cutout portion 120, left cutout portion 160) having a substantially rectangular shape when viewed from the side, the front and upper sides of the cutout portion being open.

With this configuration, the flow of the air taken into the engine hood 10 from the ventilation hole 30 can be appropriately adjusted by the pair of flow straightening plates 100 (the right flow straightening plate 110 and the left flow straightening plate 150).

Specifically, the air taken in from the vent hole 30 between the vent hole 30 and the rectifying plate 100 (i.e., on the side of the cooling unit 90) can be guided to the front of the cooling unit 90 through two paths, i.e., a path guided from the front end portion of the rectifying plate 100 and a path guided from the notch portion of the rectifying plate, which are different from each other in the front-rear direction position.

That is, the air taken in from the air hole 30 between the air hole 30 and the rectifying plate 100 can be guided to the position where the vertical positions are different from each other and to the position where the front-rear positions of the cooling unit 90 are different from each other, so that an appropriate air volume can be supplied according to the need of the cooling unit 90. This can improve the cooling efficiency of the cooling unit 90.

Further, for example, the intake resistance as a whole is reduced as compared with a case where the cutout portions (the right cutout portion 120, the left cutout portion 160) are not provided, and therefore the air volume of the whole inside of the engine cover 10 can be increased.

Further, since the air volume of the entire interior of the engine cover 10 can be increased without increasing the rotation speed of the cooling fan 40, an increase in noise of the cooling fan 40 can be suppressed.

In addition, in the tractor 1,

the cutout portions (right cutout portion 120, left cutout portion 160) have corner portions (right corner portion 131, left first corner portion 171, left second corner portion 172) formed by two sides and having an angle of substantially 90 degrees.

With this configuration, more air can be taken in by, for example, the right corner 131. In this way, particularly when heat is stagnated or concentrated, or when air is to be further flowed, the air can be efficiently guided by providing the right corner 131 in the vicinity of a necessary portion (in the present embodiment, the fuel cooler 70).

In addition, in the tractor 1,

the notch portions of the pair of rectifying plates 100 include a left first notch portion 161 and a left second notch portion 162, and the left first notch portion 161 and the left second notch portion 162 have a stepped step that descends forward.

With this configuration, the step difference is also provided in the notch portion of the flow straightening plate 100, and thus the air taken in from the air hole 30 between the air hole 30 and the flow straightening plate 100 can be guided to the front of the cooling unit 90 through a plurality of paths having different positions in the front-rear direction.

In addition, in the tractor 1,

the notch portions of the pair of rectifying plates 100 include a right second notch 122, a right third notch 124, a left third notch 163, and a left fourth notch 164, each of which is formed in a notch shape at a corner portion of the notch that is open in the forward direction.

With this configuration, the air taken in from the vent hole 30 between the vent hole 30 and the rectifying plate 100 can be guided to the front of the cooling unit 90 via the rectifying plate 100 as smoothly as possible.

In addition, in the tractor 1,

the vent hole 30 of the hood 10 has a first portion overlapping the rectifying plate 100 in a side view and a second portion (non-overlapping portion 31a, non-overlapping portion 32 a) non-overlapping with the rectifying plate 100,

the second portion is provided so as to span the lower end portions of the cutout portions (the right-side first cutout portion 121, the left-side first cutout portion 161, the left-side second cutout portion 162) in the up-down direction.

With this configuration, the air that is guided to the front of the cooling unit 90 can be made to include not only the air that is guided through the rectifying plate 100 but also the air that is not guided through the rectifying plate 100.

In addition, in the tractor 1,

The cooling unit 90 has a plurality of coolers whose cooling objects are different from each other,

the plurality of coolers includes a radiator 50 (first cooler) and a condenser 80, an oil cooler 60, a fuel cooler 70 (second cooler), the condenser 80, the oil cooler 60, the fuel cooler 70 (second cooler) are disposed in front of the radiator 50 (first cooler) and the height position of the upper end portion is formed lower than that of the radiator 50 (first cooler),

the cutout portions of the pair of rectifying plates 100 include cutout portions (right cutout portion 120, left cutout portion 160) provided at positions apart from the radiator 50 (first cooler) forward in a side view.

With this configuration, air (air that does not pass through the condenser 80, the oil cooler 60, and the fuel cooler 70 (second cooler)) having no temperature rise can be supplied to the first cooler (radiator 50).

In addition, in the tractor 1,

the cutout portions of the pair of rectifying plates 100 include a right first cutout portion 121 and a left first cutout portion 161, and the right first cutout portion 121 and the left first cutout portion 161 are provided above the condenser 80, the oil cooler 60, and the fuel cooler 70 (second cooler) in a side view.

With this configuration, the air guided from the right side first cutout 121 and the left side first cutout 161 of the rectifying plate 100 to the front of the cooling unit 90 is not supplied to the condenser 80, the oil cooler 60, and the fuel cooler 70 (second cooler), and thus it is possible to suppress the supply of excessive air to these second coolers.

In addition, in the tractor 1,

the second cooler includes an oil cooler 60, a fuel cooler 70 (third cooler), and a condenser 80 (fourth cooler) provided in front of the oil cooler 60, the fuel cooler 70 (third cooler),

the condenser 80, the oil cooler 60, and the fuel cooler 70 (the third cooler and the fourth cooler) are provided so that one of the left and right sides does not overlap and the other of the left and right sides overlaps when viewed from the front,

the cutout portions of the pair of rectifying plates 100 are formed to be larger than the left cutout portion 160 on the other of the left and right sides than the right cutout portion 120 on the other of the left and right sides in a side view.

With this configuration, it is possible to guide relatively large amounts of air to the condenser 80, the oil cooler 60, and the fuel cooler 70 (the third cooler and the fourth cooler) on the side where they overlap when viewed from the front, and to guide relatively small amounts of air to the side where they do not overlap.

In this way, it is possible to suppress the supply of excessive air to the condenser 80, the oil cooler 60, and the fuel cooler 70 (the third cooler and the fourth cooler), and to improve the cooling efficiency.

The tractor 1 according to the present embodiment is an embodiment of a work vehicle.

The right and left cutout portions 120 and 160 according to the present embodiment are one embodiment of the cutout portions.

The right rectifying plate 110 and the left rectifying plate 150 according to the present embodiment are one embodiment of rectifying plates.

The non-overlapping portions 31a and 32a according to the present embodiment are one embodiment of the non-overlapping second portions.

The radiator 50 according to the present embodiment is an embodiment of the first cooler.

The condenser 80, the oil cooler 60, and the fuel cooler 70 according to the present embodiment are one embodiment of a second cooler.

The oil cooler 60 and the fuel cooler 70 according to the present embodiment are one embodiment of a third cooler.

The condenser 80 according to the present embodiment is an embodiment of a fourth cooler.

The right corner 131, the left first corner 171, and the left second corner 172 according to the present embodiment are one embodiment of the corners.

The embodiments of the present invention have been described above, but the present invention is not limited to the above configuration, and various modifications can be made within the scope of the invention described in the claims.

For example, in the present embodiment, the tractor 1 is exemplified as the working vehicle, but the present invention is not limited to this. For example, the work vehicle may be another agricultural vehicle, a construction vehicle, an industrial vehicle, or the like.

In the present embodiment, the cooling unit 90 is considered to include the radiator 50, the oil cooler 60, the fuel cooler 70, and the condenser 80, but is not limited thereto. The arrangement structure of the radiator 50, the oil cooler 60, the fuel cooler 70, and the condenser 80 is not limited to the structure according to the present embodiment, and any arrangement structure may be employed.

The structure of the rectifying plate 100 is not limited to the structure according to the present embodiment. For example, the right rectifying plate 110 and the left rectifying plate 150 may not have all of the notched portions according to the present embodiment. The right rectifying plate 110 and the left rectifying plate 150 may have different notched portions from those according to the present embodiment.

The right rectifying plate 110 and the left rectifying plate 150 may be formed such that the front ends (portions facing forward) are bent toward the vehicle body inside. With this configuration, air can be more smoothly guided to the cooling unit 90 side. The right and left rectifying plates 110 and 150 may be positioned at the upper and front ends in the immediate vicinity of the hood 10. With this configuration, for example, when the hood 10 in the open state is closed, if the hood 10 is closed in a state where the front end side of the hood 10 is inclined in the right-left direction, the inside of the hood 10 can be brought into close contact with the right rectifying plate 110 and the left rectifying plate 150, and the hood 10 can be guided to a correct position.

In the present embodiment, the left first notch 161 and the left second notch 162 are formed in a step shape having one step, but may have two or more steps.

In the present embodiment, the right corner 131 is provided in the vicinity of the fuel cooler 70, but the present invention is not limited to this. That is, the right corner 131 is provided near any portion such as a portion where heat stagnates or concentrates and a portion where air is desired to flow further, and thus more air can be guided to the portion and cooled efficiently.

As described above, the tractor 1 (work vehicle) according to the present embodiment includes:

an oil cooler 60 formed in a substantially rectangular shape when viewed from the front, the oil cooler 60 having an outlet port 63 and an inlet port 62 (connection port) on the right side (left-right direction side) of the oil cooler 60;

an oil outlet passage 200 (oil supply passage), the oil outlet passage 200 being connected to the inlet port 62 (one of the upper and lower connection ports) and supplying oil to the oil cooler 60;

an oil circuit 300 (oil discharge passage), the oil circuit 300 being connected to the outlet port 63 (upper and lower connection port) and discharging oil from the oil cooler 60; and

A check valve 400 (valve), the check valve 400 being formed in an elongated shape, and allowing oil to flow in the check valve 400 from one side in the length direction toward the other side in the length direction according to the hydraulic pressure of one side in the length direction of the check valve 400,

the end portion of the check valve 400 (valve) on one side in the longitudinal direction is connected to a first connection portion 510 (first connection portion), the first connection portion 510 connects the inlet port 62 (one connection port) to the oil outlet passage 200 (oil supply passage), the end portion of the check valve 400 on the other side in the longitudinal direction is connected to a second connection portion 520 (second connection portion), the second connection portion 520 connects the outlet port 63 (the other connection port) to the oil circuit 300 (oil discharge passage), and the check valve 400 is arranged such that the longitudinal direction is oriented in the up-down direction.

With this configuration, the space on the side of the oil cooler 60 can be effectively utilized, and space saving can be achieved.

In addition, in the tractor 1 (work vehicle),

the check valve 400 (valve) includes a plurality of tubular members (a lower member 410, an intermediate member 430, and an upper member 420) configured to allow oil to flow in the longitudinal direction,

the plurality of cylindrical members have one cylindrical member and the other cylindrical member adjacent to each other in the longitudinal direction,

The portion of the one tubular member and the other tubular member, which overlap each other at the position in the longitudinal direction, is inserted into the other tubular member so as to be movable relative to each other via a substantially annular first seal member (upper O-ring 451 and lower O-ring 452).

With this structure, the vertical deviation of check valve 400 can be absorbed, and the assembling property and workability can be improved.

In addition, in the tractor 1 (work vehicle),

the plurality of cylindrical members includes:

a lower member 410, the lower member 410 being connected to the first connection portion 510 (first connection portion);

an upper member 420, the upper member 420 being connected to the second connection portion 520 (second connection portion); and

an intermediate member 430, the intermediate member 430 being disposed between the lower member 410 and the upper member 420 in the longitudinal direction and being adjacent to each other with the lower member 410 and the upper member 420,

the lower member 410 and the intermediate member 430 are inserted as the one tubular member and the other tubular member, respectively, one with respect to the other,

the upper member 420 and the intermediate member 430 are inserted as the one tubular member and the other tubular member, respectively, one with respect to the other.

With this configuration, the intermediate member 430 can be moved in the longitudinal direction relative to the lower member 410 and the upper member 420, and therefore, the vertical deviation of the check valve 400 can be absorbed, and the assembling property and workability can be improved.

In addition, in the tractor 1 (work vehicle),

the intermediate member 430 has:

an intermediate reduced diameter portion 432 (valve seat), the intermediate reduced diameter portion 432 being provided inside the intermediate member 430;

a valve member 455 slidably disposed in the middle member 430 in the longitudinal direction; and

a spring 456 (urging member), the spring 456 urging the valve body toward the valve seat against the hydraulic pressure on the longitudinal side.

With this configuration, in the check valve 400 formed by combining a plurality of members, the main configuration is integrated into one member (intermediate member 430), and therefore simplification of the overall structure of the valve can be achieved.

In addition, in the tractor 1 (work vehicle),

the check valve 400 has a lower head through hole 414 (first through hole), and the lower head through hole 414 penetrates an end portion of the check valve 400 on one side in the longitudinal direction in the lateral direction,

The check valve 400 is connected to the first connection portion 510 (first connection portion) via a first bolt 511 (first fastening member) inserted through the lower head through hole 414 (first through hole) on the other side in the lateral direction.

With this configuration, when assembling, the check valve 400 can be swung in the front-rear direction around the end portion on the one side in the longitudinal direction of the check valve 400, and therefore, the assembling property and workability can be improved.

In addition, in the tractor 1 (work vehicle),

the check valve 400 has an upper head through hole 424 (second through hole), the upper head through hole 424 penetrates the other end portion of the check valve 400 in the longitudinal direction in the lateral direction,

the check valve 400 is connected to the second connection portion 520 (second connection portion) via a second bolt 521 (second fastening member) inserted through the upper head through hole 424 (second through hole) toward the other side in the lateral direction.

With this configuration, when assembling, the check valve 400 can be swung in the front-rear direction around the end portion on the other side in the longitudinal direction of the check valve 400, and therefore, the assembling property and workability can be improved.

In addition, in the tractor 1 (work vehicle),

The upstream side end portion (end portion on the second connecting portion side) of the oil circuit 300 (oil discharge oil passage) is configured to,

the upstream side end (end on the second connecting portion side) is oriented in the longitudinal direction in the up-down direction, and is adjacent to the check valve 400 (valve).

With this configuration, the space on the side of the oil cooler 60 can be effectively utilized, and space saving can be achieved.

In addition, in the tractor 1 (work vehicle),

the downstream side end portion (end portion on the first connection portion side) of the oil outlet passage 200 (oil supply passage) is configured to,

the downstream side end (end on the first connecting portion side) is oriented in the longitudinal direction in the up-down direction, and extends downward from the check valve 400 (valve).

With this configuration, the space on the side of the oil cooler 60 can be effectively utilized, and space saving can be achieved.

In addition, in the tractor 1 (work vehicle),

the downstream end portion (end portion on the first connection portion side) of the oil outlet passage 200 (oil supply passage) is provided with:

a joint main body portion 235 (first supply oil passage side connection portion), the joint main body portion 235 being included in the first connection portion 510 and having a joint main body through hole 244 (third through hole) penetrating in the left-right direction;

A forward pipe 210 (flow path portion), the forward pipe 210 serving as a flow path for oil; and

a joint ring portion 236 and a joint nut portion 237 (fixing means), the joint ring portion 236 and the joint nut portion 237 fixing the joint main body portion 235 (first supply oil passage side connection portion) and the outgoing pipe 210 (flow passage portion),

the joint main body portion 235 (first supply oil passage side connection portion) is connected to the introduction port 62 (one connection port) via a first bolt 511 (third fastening member), the first bolt 511 is inserted into the joint main body through hole 244 (third through hole) to the left (left-right direction other side), and the joint main body portion 235 is fixed to the outgoing pipe 210 (flow passage portion) by the joint ring portion 236 and the joint nut portion 237 (fixing means) in a state of being connected to the outgoing pipe 210 (flow passage portion) so as to be movable relatively.

With such a configuration, when assembling, the forward pipe 210 (oil supply passage) can be swung in the forward-backward direction about the first bolt 511 (third fastening member), or the forward pipe 210 (flow path portion) can be arbitrarily moved (e.g., rotated about the axis) with respect to the joint main body portion 235 (first supply passage side connection portion), so that assembling property and workability can be improved.

In addition, in the tractor 1,

the oil cooler 60 is disposed inside the engine cover 10, and the oil cooler 60 is disposed in front of the engine 3.

With this structure, the space on the side of the oil cooler 60 can be effectively utilized in front of the engine 3 in the engine cover 10, and space saving can be achieved.

The check valve 400 according to the present embodiment is an embodiment of a valve.

The export port 63 and import port 62 according to the present embodiment are one embodiment of connection ports.

The oil outlet passage 200 according to the present embodiment is an embodiment of an oil supply passage.

The oil circuit 300 according to the present embodiment is an embodiment of an oil discharge passage.

The first connection portion 510 according to the present embodiment is an embodiment of a first connection portion.

The second connection portion 520 according to the present embodiment is an embodiment of a second connection portion.

The lower member 410, the intermediate member 430, and the upper member 420 according to the present embodiment are one embodiment of a plurality of tubular members.

The upper O-ring 451 and the lower O-ring 452 according to the present embodiment are one embodiment of the first sealing member.

The spring 456 according to the present embodiment is an embodiment of a biasing member.

The intermediate reduced diameter portion 432 according to the present embodiment is an embodiment of a valve seat.

The lower head through hole 414 according to the present embodiment is an embodiment of the first through hole.

The first bolt 511 according to the present embodiment is an embodiment of a first fastening member.

The upper head through hole 424 according to the present embodiment is an embodiment of the second through hole.

The second bolt 521 according to the present embodiment is an embodiment of a second fastening member.

The joint body through hole 244 according to the present embodiment is an embodiment of a third through hole.

The joint main body 235 according to the present embodiment is an embodiment of the first supply oil passage side connection portion.

The joint ring portion 236 and the joint nut portion 237 according to the present embodiment are one embodiment of a fixing means.

The first bolt 511 according to the present embodiment is an embodiment of the third fastening member.

The embodiments of the present invention have been described above, but the present invention is not limited to the above configuration, and various modifications can be made within the scope of the present invention.

For example, in the present embodiment, the oil cooler 60 is considered to be disposed inside the engine cover 10, but is not limited thereto. The oil cooler 60 is considered to be disposed in front of the engine 3, but is not limited thereto.

The check valve 400 is disposed with its upstream side facing downward and its downstream side facing upward, but may be disposed with its opposite direction. The check valve 400 is formed of three cylindrical members, but may be two or four or more. The check valve 400 is connected to the lower member 410 and the upper member 420 so as to be movable with respect to the intermediate member 430 via an O-ring, but may be connected to a state in which not both the lower member 410 and the upper member 420 but either one is movable with respect to the intermediate member via an O-ring. Further, the lower member 410 and the upper member 420 are inserted into the middle member 430 with respect to the middle member 430, but the middle member 430 may be inserted into the lower member 410 and the upper member 420.

As described above, the tractor 1 (work vehicle) according to the present embodiment includes:

a downstream piping 212 (first pipe), the downstream piping 212 being configured to supply oil (fluid) to circulate;

An upstream-downstream piping 211 (second piping), the upstream-downstream piping 211 being configured to circulate the oil (fluid), the upstream-downstream piping 211 being more flexible than the downstream-downstream piping 212 (first piping); and

a block joint 250, the block joint 250 connecting the downstream piping 212 (first piping) and the upstream piping 211 (second piping).

With this configuration, the pipelines having different flexibilities can be connected via the block joint 250, and thus the degree of freedom in design can be improved.

In this way, the forward downstream pipe 212 (first pipe) and the forward upstream pipe 211 (second pipe) can be appropriately selected and used according to the location, application, and the like. For example, the downstream piping 212 (first piping) can be used to improve strength, shock resistance, and durability. In addition, the upstream piping 211 (second piping) can be used, which can reduce the cost and facilitate assembly.

In addition, in the tractor 1,

the block joint 250 is formed of a substantially hexahedral shape (polyhedron),

the forward downstream pipe 212 (first pipe) is connected to the front surface 265 (predetermined surface) of the block joint 250,

the forward upstream pipe 211 (second pipe) is connected to an upper surface 261 (other surface) of the block joint 250 adjacent to the front surface 265 (predetermined surface).

With such a configuration, a predetermined angle can be provided between the forward downstream pipe 212 (first pipe) and the forward upstream pipe 211 (second pipe) by a simple configuration.

In the present embodiment, the block joint 250 is formed by forming holes in two surfaces adjacent to each other in a block-shaped member (block body portion 251). In this way, the block joint 250 can be formed with a simple structure, and thus can be reduced in cost.

In addition, in the tractor 1,

the block joint 250 is fixed to the flywheel housing 4 (fixed member) to which the block joint 250 is fixed, in a state separated from the flywheel housing via a bracket 270.

With this configuration, the influence of the vehicle body sway on the connection portion (block joint 250) between the forward downstream pipe 212 (first pipe) and the forward upstream pipe 211 (second pipe) can be suppressed.

In addition, in the tractor 1,

the bracket 270 is formed to extend from a bracket fixing portion 271 that fixes the bracket 270 and the flywheel housing 4 (fixed member) toward a joint fixing portion 273 that fixes the bracket 270 and the block joint 250,

the forward upstream piping 211 (second piping) is provided along a direction extending from the bracket 270.

With this configuration, space saving can be achieved.

In addition, in the tractor 1,

the fixed member is constituted by the flywheel housing 4.

With such a configuration, the flywheel housing 4 can be used to improve the degree of freedom in design.

In addition, in the tractor 1,

the bracket 270 is fixed to a mounting table 23 provided in a convex shape at an upper side portion of the flywheel housing 4,

the mounting table 23 is provided with a substantially horizontal surface on the upper surface side of the convex shape.

With this configuration, the bracket 270 can be provided at a place where the flywheel housing 4 is relatively easy to be stably fixed, and the vicinity of the flywheel housing 4 (a place where the flywheel housing is relatively difficult to be effectively used) can be effectively utilized.

In addition, in the tractor 1,

the block joint 250 is provided so as to overlap the flywheel housing 4 in a side view and so as to be located inside the flywheel housing 4 in the up-down-left-right direction.

With this configuration, the vicinity of the flywheel housing 4 (a place where effective use is relatively difficult) can be effectively utilized. In addition, interference of the block joint 250 with other members can be easily suppressed.

In addition, in the tractor 1,

the mount 23 mounts the bracket 270 and the hood support member 24.

With this structure, the flywheel housing 4 can be effectively utilized in the vicinity of the mounting bracket 270 and the hood support member 24 (without providing a separate dedicated site for mounting), which makes it possible to effectively utilize the flywheel housing in a relatively difficult place.

The forward downstream pipe 212 according to the present embodiment is an embodiment of the first pipeline.

The forward upstream piping 211 according to the present embodiment is an embodiment of the second pipeline.

The block joint 250 according to the present embodiment is an embodiment of a joint.

The flywheel housing 4 according to the present embodiment is an embodiment of a fixed member.

The mount 23 according to the present embodiment is an embodiment of a mount.

The embodiments of the present invention have been described above, but the present invention is not limited to the above configuration, and various modifications can be made within the scope of the invention.

For example, the piping to which the block joint 250 is connected is not limited to the outgoing upstream piping 211 (second piping) and the outgoing downstream piping 212 (first piping) according to the present embodiment, and any piping may be connected. In the present embodiment, the upstream-side piping 211 is considered to be a rubber piping and the downstream-side piping 212 is considered to be a metal piping, but the present invention is not limited thereto. That is, the material of the piping to which the block joint 250 is connected may be arbitrarily selected. The fluid flowing through the pipe connected to the block joint 250 is not limited to oil, and may be any fluid.

Further, the block joint 250 is considered to be formed of a substantially hexahedron, but may be formed of any polyhedron such as a substantially octahedron.

Further, the block joint 250 is regarded as being fixed to the flywheel housing 4, but may be fixed to a member different from the flywheel housing 4. Further, although the block joint 250 is considered to be mounted to the mount 23 (for mounting the hood support member 24), the block joint 250 may be mounted to any portion of the flywheel housing 4. The block joint 250 may be directly attached to the mount 23 without the bracket 270.

Claims (9)

1. A work vehicle is characterized by comprising:

an oil cooler formed in a substantially rectangular shape when viewed from the front, the oil cooler having connection ports at the upper and lower sides of one side in the lateral direction;

an oil supply passage that is connected to the connection port of either one of the upper and lower portions and that supplies oil to the oil cooler;

an oil discharge passage that is connected to the connection port of the other of the upper and lower side and that discharges oil from the oil cooler; and

a valve which is formed in an elongated shape and allows oil to flow in the valve from one side in the longitudinal direction toward the other side in the longitudinal direction according to the hydraulic pressure of one side in the longitudinal direction of the valve,

The valve may be configured such that one of the connection ports is connected to the oil supply passage, the other of the connection ports is connected to a second connection portion, the second connection portion connects the other of the connection ports to the oil discharge passage, the valve is arranged such that the longitudinal direction is oriented in the up-down direction,

the valve has a plurality of cylindrical members configured to allow oil to flow in the longitudinal direction,

the plurality of cylindrical members have one cylindrical member and the other cylindrical member adjacent to each other in the longitudinal direction,

the portion of the one tubular member and the other tubular member, which overlap each other at the position in the longitudinal direction, is inserted into one of the other tubular members so as to be movable relative to the other tubular member via the substantially annular first seal member.

2. The work vehicle of claim 1, wherein the vehicle is configured to,

the plurality of cylindrical members includes:

a lower member connected to the first connection portion;

an upper member connected to the second connection portion; and

an intermediate member that is provided between the lower member and the upper member in the longitudinal direction and that is adjacent to the lower member and the upper member,

The lower member and the intermediate member are inserted as the one tubular member and the other tubular member, respectively, one with respect to the other,

the upper member and the intermediate member are inserted as the one tubular member and the other tubular member, respectively, one with respect to the other.

3. The work vehicle of claim 2, wherein the vehicle is configured to,

the intermediate member has:

a valve seat provided inside the intermediate member;

a valve body slidably provided in the middle member in the longitudinal direction; and

and a biasing member that biases the valve element toward the valve seat against the hydraulic pressure on the longitudinal side.

4. A working vehicle as claimed in any one of claims 1 to 3, characterized in that,

the valve has a first through-hole penetrating an end portion of the valve on one side in the longitudinal direction in the lateral direction,

the valve is connected to the first connection portion via a first fastening member inserted through the first through hole on the other side in the left-right direction.

5. A working vehicle as claimed in any one of claims 1 to 3, characterized in that,

The valve has a second through hole penetrating an end portion of the valve on the other side in the longitudinal direction in the lateral direction,

the valve is connected to the second connection portion via a second fastening member inserted through the second through hole to the other side in the lateral direction.

6. A working vehicle as claimed in any one of claims 1 to 3, characterized in that,

the second connection portion side end portion of the oil discharge passage is disposed such that a longitudinal direction of the second connection portion side end portion is oriented in the up-down direction, and the second connection portion side end portion is adjacent to the valve.

7. A working vehicle as claimed in any one of claims 1 to 3, characterized in that,

the first connection-side end portion of the oil supply passage is disposed such that a longitudinal direction of the first connection-side end portion is oriented in the up-down direction, and the first connection-side end portion extends downward from the valve.

8. A working vehicle as claimed in any one of claims 1 to 3, characterized in that,

the oil supply passage is provided with:

a first supply oil passage side connection portion that is included in the first connection portion and has a third through hole that penetrates in the left-right direction;

A flow path portion that serves as a flow path for oil; and

a fixing unit that fixes the first supply oil passage side connection portion and the flow path portion,

the first supply oil passage side connection portion is connected to one of the connection ports via a third fastening member that is inserted through the third through hole to the other side in the left-right direction, and is fixed to the flow passage portion by the fixing means in a state where the first supply oil passage side connection portion is connected to the flow passage portion so as to be movable relative to the flow passage portion.

9. A working vehicle as claimed in any one of claims 1 to 3, characterized in that,

the oil cooler is disposed inside the engine cover,

and the oil cooler is provided in front of the engine.

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