CN110905752A

CN110905752A - Swash plate, swash plate with shaft-like member, and hydraulic device

Info

Publication number: CN110905752A
Application number: CN201910798063.9A
Authority: CN
Inventors: 赤见俊也; 山口祥
Original assignee: Nabtesco Corp
Current assignee: Nabtesco Corp
Priority date: 2018-08-27
Filing date: 2019-08-27
Publication date: 2020-03-24
Also published as: JP2020033888A; KR20200024103A; JP7118810B2

Abstract

The invention provides a swash plate, a swash plate with a shaft member, and a hydraulic device. A hydraulic device (10) is provided with: a swash plate (50); a swash plate support part (13) that supports the swash plate; a shaft-like member (40) held by a groove (55), the groove (55) being formed in the swash plate; and an adjusting member (37) which adjusts the inclination of the swash plate by pressing the shaft-like member. The groove portion is open at both ends, and the width (Wx) is narrowed at both ends.

Description

Swash plate, swash plate with shaft-like member, and hydraulic device

Technical Field

The present invention relates to a swash plate, a swash plate with a shaft member, and a hydraulic device.

Background

For example, as disclosed in patent document 1(JP2002-242825a), a hydraulic device using a swash plate is known. In the hydraulic device disclosed in patent document 1, a swash plate is disposed to face a piston, and the operating range of the piston is restricted. In this hydraulic apparatus, the capacity of the cylinder chamber housing the piston can be changed by deflecting the swash plate, that is, by changing the inclination of the swash plate, and the output from the hydraulic apparatus can be controlled.

In the example disclosed in patent document 1, the swash plate can be tilted by being pressed by the control piston. As shown in fig. 2 of patent document 1, the swash plate is formed with a recess, and the pin is held by the recess. The control piston presses the swash plate by contacting the pin to deflect the swash plate. By forming the pin of a harder material than the material of the swash plate, the durability of the hydraulic device can be improved while suppressing an increase in cost of the hydraulic device.

However, when a shaft-like member such as a pin is used, it is necessary to prevent the shaft-like member from coming off. As also disclosed in patent document 1, generally, the movement of the shaft-like member in the direction orthogonal to the axial direction thereof is restricted by the control piston and the swash plate. Therefore, in order to prevent the shaft-like member from coming off, it is necessary to restrict the axial movement of the shaft-like member.

It is envisioned that: the shaft-like member is held by the swash plate from the outside in the axial direction of the shaft-like member, or the shaft-like member is fixed to the swash plate by using a fastener such as a retainer ring or a bolt, whereby the shaft-like member can be prevented from moving in the axial direction. However, if the swash plate is configured to hold the shaft-like member from the axial direction, the swash plate is increased in size. In addition, the use of the fastener is a cause of cost increase, and a new problem of detachment of the fastener may occur.

Disclosure of Invention

The present invention has been made in view of the above points, and an object of the present invention is to prevent a shaft-like member from coming off while suppressing an increase in size of a swash plate in a hydraulic device having the swash plate.

The 1 st hydraulic device of the present invention includes:

a piston;

a swash plate disposed opposite to the pistons;

a shaft-like member held in a groove portion provided in the swash plate;

a swash plate support portion that supports the swash plate; and

an adjustment member that adjusts the inclination of the swash plate by pressing the shaft-like member,

the groove portion has: a central portion for holding the shaft-like member; and narrow width portions which are located on both sides of the central portion and have a width smaller than that of the central portion.

The 2 nd hydraulic device of the present invention includes:

a sloping plate; a swash plate support portion that supports the swash plate; a shaft-like member held in a groove portion formed in the swash plate; and an adjusting member that adjusts the inclination of the swash plate by pressing the shaft-like member, wherein,

the width of both end portions of the groove portion is narrower than the width of the central portion of the groove portion.

The 3 rd hydraulic device of the present invention includes:

a swash plate disposed to face the piston and provided with a groove portion having: a central portion; and narrow width portions which are located on both sides of the central portion and have a width narrower than that of the central portion;

a shaft-like member held at the central portion of the groove portion;

a swash plate support portion that supports the swash plate; and

an adjustment member that adjusts the inclination of the swash plate by pressing the shaft-like member.

In the 1 st to 3 rd hydraulic devices according to the present invention, the groove portion may be open at both ends of the groove portion.

In the 1 st to 3 rd hydraulic devices according to the present invention, the width of the groove portion may be narrower at both end portions of the groove portion than at the central portion.

In the 1 st to 3 rd hydraulic devices according to the present invention, the groove portion may include a curved side wall at the narrow portion.

In the 1 st to 3 rd hydraulic devices according to the present invention, the shaft-like member may have curved side surfaces at both ends of the groove portion.

In the 1 st to 3 rd hydraulic devices according to the present invention, the narrow portions may be both end portions of the groove portion.

In the 1 st to 3 rd hydraulic devices according to the present invention, the swash plate may have a protruding portion that is provided in the narrow portion of the groove portion and protrudes into the groove portion.

In the 1 st to 3 rd hydraulic devices according to the present invention, the protrusion may be formed as the curved side wall.

In the 1 st to 3 rd hydraulic apparatuses according to the present invention, it is also possible that,

the protrusion has a 1 st part and a 2 nd part arranged in a depth direction of the groove portion,

the 1 st portion connected to the bottom wall of the groove portion has a longer protruding length in the width direction than the 2 nd portion.

the swash plate has: a 1 st protruding part and a 2 nd protruding part which are respectively provided at both end parts of the groove part and protrude into the groove part; and a 3 rd protruding part provided between the 1 st and 2 nd protruding parts and protruding into the groove part,

the 3 rd protruding part is connected with the bottom wall of the groove part and extends along the length direction of the groove part.

In the 1 st to 3 rd hydraulic devices of the present invention,

the groove portion includes a 1 st side wall and a 2 nd side wall opposed in a width direction,

the protrusion may be provided on both the 1 st side wall and the 2 nd side wall, or may be provided only on one of the 1 st side wall and the 2 nd side wall.

The swash plate with a shaft-like member for a 1 st hydraulic device according to the present invention includes:

a swash plate disposed opposite to the piston; and

a shaft-like member held in a groove portion provided in the swash plate and pressed by an adjustment member to adjust the inclination of the swash plate,

The swash plate with a shaft-like member for a 2 nd hydraulic device according to the present invention includes:

a swash plate disposed to face the piston and provided with a groove portion having: a central portion; and narrow width portions which are located on both sides of the central portion and have a width narrower than that of the central portion; and

and a shaft-like member held at the center of the groove portion and capable of being pressed by an adjusting member for adjusting the inclination of the swash plate.

The swash plate for a hydraulic device of the present invention is a swash plate disposed to face a piston, wherein,

the swash plate is provided with a groove portion having: a central portion for holding a shaft-like member that is pressed by an adjusting member in order to adjust the inclination of the swash plate; and narrow width portions which are located on both sides of the central portion and have a width smaller than that of the central portion.

According to the present invention, in a hydraulic apparatus having a swash plate, it is possible to effectively prevent the shaft-like member from coming off while suppressing an increase in size of the swash plate.

Drawings

Fig. 1 is a diagram for explaining an embodiment of the present invention, and is a vertical cross-sectional view showing an example of a hydraulic apparatus.

Fig. 2 is a perspective view showing an example of a swash plate and a shaft-like member that can be incorporated in the hydraulic apparatus of fig. 1.

Fig. 3 is a perspective view showing a groove portion of the swash plate of fig. 2.

Fig. 4 is a plan view showing the groove portion of the swash plate of fig. 3 together with a shaft-like member fitted into the groove portion.

Fig. 5 is a sectional view taken along line V-V of fig. 4.

Fig. 6 is a diagram for explaining a method of manufacturing the groove portion of fig. 3, and is a plan view showing the swash plate.

Fig. 7 is a diagram for explaining a method of forming the groove portion in fig. 3, and shows a state of fig. 6 from the rear in a moving direction (feeding direction) of the cutting tool.

Fig. 8 is a diagram for explaining a method of forming the groove portion in fig. 3, and shows steps to be performed after the step in fig. 6 from the same direction of observation as in fig. 6.

FIG. 9 is a view for explaining a method of forming the groove of FIG. 3, and is a cross-sectional view taken along line IX-IX of FIG. 8.

Fig. 10 corresponds to fig. 3, and is a view for explaining another example of the groove portion.

Fig. 11 is a view corresponding to fig. 4, and is a plan view showing the groove portion and the shaft-like member of the swash plate of fig. 10.

Fig. 12 is a view corresponding to fig. 5, and is a sectional view taken along line XII-XII of fig. 11.

Fig. 13 corresponds to fig. 4, and is a diagram for explaining still another example of the groove portion.

Fig. 14 corresponds to fig. 2, and is a diagram for explaining a modification of the shaft-like member.

Detailed Description

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. For ease of understanding, elements shown in the drawings may include elements whose dimensions, scales, and the like are different from actual dimensions, scales, and the like.

The hydraulic device 10 described below is a so-called variable displacement type piston pump/motor using a swash plate, and can be used as two actuators, i.e., a pump and a motor. In the case where the hydraulic apparatus 10 is flexibly used as a hydraulic pump, the hydraulic apparatus 10 sucks the working oil into the cylinder chamber 21, which will be described later, and discharges the working oil from the cylinder chamber 21. On the other hand, in the case of flexibly employing the hydraulic device 10 as a hydraulic motor, the hydraulic device 10 outputs rotation of the rotary shaft member 18, which will be discussed later. More specifically, when the hydraulic device 10 according to the embodiment described below is used as a pump, the rotary shaft member 18 is rotated by power from a power source such as an engine, the cylinder block 20 coupled to the rotary shaft member 18 by spline coupling or the like is rotated, and the piston 25 is reciprocated by the rotation of the cylinder block 20. By this reciprocating operation of the piston 25, the hydraulic oil is discharged from some of the cylinder chambers 21 and sucked into the other cylinder chambers 21, thereby realizing the hydraulic pump. On the other hand, when the hydraulic device 10 is used as a motor, the hydraulic oil is caused to flow into the cylinder chamber 21 by the power from the power source and is discharged from the other cylinder chamber 21, so that the pistons are caused to slide and rotate on the swash plate while reciprocating the pistons. Since the cylinder 20 and the rotary shaft member 18 are also rotated in accordance with the rotation of the piston 25, a hydraulic motor can be realized by utilizing the rotation of the rotary shaft member 18. Typically, the hydraulic device 10 can be used as a hydraulic circuit or a drive device provided in a construction machine, and can be applied to other applications, and the application is not particularly limited.

The hydraulic apparatus 10 of the type shown in the drawings using a swash plate includes: the housing 15, the rotary shaft member 18, the cylinder block 20, the pistons 25, the valve plate 30, the yaw adjusting mechanism 35, and the swash plate 50 constitute main components. Hereinafter, each constituent element will be described.

As shown in fig. 1, the housing 15 has a 1 st housing block 15a and a 2 nd housing block 15b fixed to the 1 st housing block 15 a. The 1 st housing block 15a and the 2 nd housing block 15b are fixed to each other using fasteners such as bolts. The housing 15 has a housing space S formed therein. The cylinder block 20, the piston 25, the valve plate 30, the yaw adjustment mechanism 35, and the swash plate 50 are disposed in the housing space S.

In the illustrated example, the valve plate 30 is fixed to the inside of the 1 st housing block 15 a. The 1 st housing block 15a has a 1 st flow path 11 and a 2 nd flow path 12 communicating with the cylinder chamber 21 of the cylinder block 20 via the valve plate 30. In the drawings, for convenience of explanation, the 1 st flow path 11 and the 2 nd flow path 12 are indicated by lines and actually have appropriate inner diameters according to supply and discharge of the hydraulic oil to and from the cylinder chamber 21 of the cylinder block 20. The 1 st flow path 11 and the 2 nd flow path 12 are provided so as to penetrate the casing 15 from inside the casing 15 to outside the casing 15. The 1 st flow path 11 and the 2 nd flow path 12 communicate with an actuator and a hydraulic pressure source provided outside the hydraulic device 10.

The rotary shaft member 18 is rotatably held by the housing 15 via a bearing 19. The rotary shaft member 18 is rotatable about its central axis line as a rotation axis RA. One end of the rotation shaft member 18 is rotatably supported by the 1 st housing block 15a via a bearing 19 a. The other end of the rotation shaft member 18 is rotatably supported by the 2 nd housing block 15b via a bearing 19b, and extends outside the housing 15 through a through hole provided in the 2 nd housing block 15 b. In the portion of the rotary shaft member 18 penetrating the housing 15, a seal member is provided between the housing 15 and the rotary shaft member 18 to prevent the working oil from flowing out of the housing 15. The portion of the rotary shaft member 18 extending from the housing 15 is connected to an external device such as an input member such as a motor or an engine, or a reduction gear.

The cylinder 20 has a cylindrical or cylindrical shape disposed around the rotation axis RA. The cylinder 20 is penetrated by the rotary shaft member 18. The cylinder block 20 is coupled to the rotary shaft member 18 by spline coupling, for example. Therefore, the cylinder block 20 can rotate about the rotation axis RA in synchronization with the rotary shaft member 18.

The cylinder block 20 has a plurality of cylinder chambers 21 formed therein. The plurality of cylinder chambers 21 are arranged at equal intervals in the circumferential direction around the rotation axis RA. Each cylinder chamber 21 extends in a direction parallel to the rotation axis RA and opens on the swash plate 50 side. Further, a connection port 22 is formed corresponding to each cylinder chamber 21. The connection port 22 opens the cylinder chamber 21 to the valve plate 30 side in the direction parallel to the rotation axis RA.

A piston 25 is provided corresponding to each cylinder chamber 21. A part of each piston 25 is disposed in the cylinder chamber 21. Each piston 25 extends from the corresponding cylinder chamber 21 toward the swash plate 50 in a direction parallel to the rotation axis RA. The piston 25 is movable relative to the cylinder 20 in a direction parallel to the rotation axis RA. That is, the piston 25 can advance toward the swash plate 50 in the direction parallel to the rotation axis RA to increase the volume of the cylinder chamber 21. The piston 25 can retract toward the valve plate 30 in a direction parallel to the rotation axis RA to reduce the volume of the cylinder chamber 21.

The swash plate 50 is supported by the housing 15. The swash plate 50 is disposed so as to face the cylinder block 20 and the piston 25 in a direction parallel to the rotation axis RA. The rotary shaft member 18 penetrates through the central through hole 51 of the swash plate 50. The swash plate 50 has a main surface 52 at a position facing the cylinder block 20 and the piston 25. The main surface 52 is inclined with respect to a plane perpendicular to the rotation axis RA, and the groove 55 is held in the housing 15. The structure for holding the swash plate 50 is discussed later.

The shoe 26 is provided on the main surface 52 of the swash plate 50. The shoe 26 holds the head of the piston 25. Specifically, a head portion serving as one end of the piston 25 is formed in a spherical shape. The shoe 26 has a hole capable of receiving substantially half of the spherical head. The shoe 26 holding the head of the piston 25 is slidable on the main surface 52 of the swash plate 50.

The hydraulic device 10 further includes a holding plate 27 disposed in the housing 15, and the holding plate 27 is an annular plate-shaped member. The holding plate 27 is penetrated by the rotary shaft member 18 and supported by the rotary shaft member 18. The support portion 18a of the rotary shaft member 18 that supports the holding plate 27 is formed in a curved surface shape. Therefore, the holding plate 27 can change its orientation while being supported by the rotary shaft member 18. As shown in fig. 1, the plate-like holding plate 27 is inclined along the main surface 52 of the swash plate 50 and contacts the shoe 26.

Further, a piston biasing member 28 formed of a spring or the like is provided between the rotary shaft member 18 and the holding plate 27. The holding plate 27 is biased toward the swash plate 50 side in the direction parallel to the rotation axis RA by the piston biasing member 28. As a result, the holding plate 27 can press the shoe 26 and the piston 25 against the main surface 52 of the swash plate 50. The rotation shaft member 18 is biased toward the valve plate 30 side in the direction parallel to the rotation axis RA by the piston biasing member 28 together with the cylinder block 20. As a result, the cylinder block 20 is pressed against the valve plate 30.

As described above, the valve plate 30 is fixed to the 1 st housing block 15 a. That is, the valve plate 30 is stationary while the cylinder block 20 rotates together with the rotary shaft member 18. The valve plate 30 has two or more ports, not shown. Each port communicates with the 1 st channel 11 or the 2 nd channel 12. The port is formed, for example, along an arc centered on the rotation axis RA, and faces the connection port 22 corresponding to each cylinder chamber 21 as the cylinder block 20 rotates. As a result, the connection between the cylinder chambers 21 and the 1 st flow path 11 and the 2 nd flow path 12 is switched according to the rotation state of the cylinder block 20.

Here, the operation of the hydraulic apparatus 10 will be described. When the hydraulic device 10 functions as a hydraulic pump, the rotary shaft member 18 rotates about the rotation axis line RA due to a rotational driving force from an input member such as a motor or an engine, not shown. At this time, the piston 25 advances so as to protrude from the cylinder 20 or retreats into the cylinder 20 as the cylinder 20 rotates. The volume of the cylinder chamber 21 changes due to the advancing and retreating operations of the piston 25.

While the piston 25 is retreating from a position (top dead center) at which it extends out to the maximum extent with respect to the cylinder chamber 21 to a position (bottom dead center) at which it enters into the cylinder chamber 21 to the maximum extent, the capacity of the cylinder chamber 21 in which the piston 25 is housed decreases. During at least a part of the period, the cylinder chamber 21 in which the piston 25 being retracted is housed is connected to, for example, the 1 st flow path 11 via a port, not shown, of the valve plate 30, and the working oil is discharged from the cylinder chamber 21. The 1 st flow path 11 is connected to an external actuator or the like as a high-pressure side flow path.

On the other hand, while the piston 25 advances from the bottom dead center to the top dead center, the capacity of the cylinder chamber 21 in which the piston 25 is housed increases. During at least a part of the period, the cylinder chamber 21 housing the advancing piston 25 is connected to, for example, the 2 nd flow path 12 via a port, not shown, of the valve plate 30, and the working oil is sucked into the cylinder chamber 21. The 2 nd flow path 12 is connected as a low-pressure side flow path to a tank or the like for storing hydraulic oil.

When the hydraulic apparatus 10 functions as a hydraulic motor, hydraulic oil is supplied from an external pump, not shown, into the cylinder chamber 21 of the hydraulic apparatus 10 through, for example, the 1 st flow path 11 and the valve plate 30. The piston 25 in the cylinder chamber 21 to which the working oil is supplied can advance so as to extend from the cylinder block 20. Therefore, the port, not shown, of the valve plate 30 connects the cylinder chamber 21 located on the path from the bottom dead center to the top dead center to the 1 st flow path 11 on the high pressure side. This enables the cylinder block 20 to be rotated by the hydraulic oil supplied from the external pump, and the rotational force to be output via the rotary shaft member 18.

The port, not shown, of the valve plate 30 connects the cylinder chamber 21 located on the path from the top dead center to the bottom dead center to the 2 nd flow path 12 on the low pressure side. Therefore, the hydraulic oil in the cylinder chamber 21 accommodating the piston 25 can be discharged to the 2 nd flow path 12 while the piston 25 is retreating from the top dead center to the bottom dead center. The hydraulic oil discharged from the hydraulic device 10 is collected by a tank or the like connected to the 2 nd flow path 12.

In the hydraulic device 10 described above, the main surface 52 of the swash plate 50 regulates the protrusion of the piston 25 with respect to the cylinder block 20. Thus, the stroke amount of the reciprocating motion of the piston 25 in the direction parallel to the rotation axis RA is determined by the degree of inclination of the main surface 52 of the swash plate 50 with respect to the surface perpendicular to the rotation axis RA. The output of the hydraulic device 10 can be changed by changing the degree of inclination of the main surface 52 of the swash plate 50 with respect to the plane perpendicular to the rotation axis RA, that is, by deflecting the swash plate 50. Specifically, when the inclination of the main surface 52 of the swash plate 50 with respect to the plane perpendicular to the rotation axis RA is large, the output of the hydraulic device 10 increases, and when the inclination of the main surface 52 of the swash plate 50 with respect to the plane perpendicular to the rotation axis RA is small, the output of the hydraulic device 10 decreases. If the main surface 52 of the swash plate 50 is perpendicular to the rotation axis RA, theoretically, no output can be obtained from the hydraulic device 10.

Therefore, in the illustrated hydraulic device 10, the swash plate 50 is held so as to be able to deflect. Hereinafter, a structure for holding the swash plate 50 in the case 15 so as to be able to deflect will be described.

As shown in fig. 1, the hydraulic device 10 includes a swash plate support portion 13 that supports the swash plate 50 so as to be able to change the inclination of the main surface 52, that is, the swash plate support portion 13 that supports the swash plate 50 so as to be able to deflect. The swash plate support portion 13 is configured as a support base on which a housing recess 14 is formed. The accommodation recess 14 has a shape corresponding to a part of a cylinder (for example, a half cylinder). The hydraulic device 10 includes two swash plate support portions 13 arranged to be spaced apart in the depth direction of the paper surface of fig. 1. The rotation shaft member 18 passes between the two swash plate support portions 13. In the illustrated example, the swash plate support portion 13 is formed as a part of the housing 15, particularly a part of the 2 nd housing block 15 b. However, the swash plate support portion 13 is not limited to this example, and may be formed separately from the housing 15 and fixed to the housing 15 by a fastener or the like.

On the other hand, the swash plate 50 has a bulging portion 53 that is accommodated by the accommodation recess 14 of the swash plate support portion 13. The bulge portion 53 has a shape complementary to the accommodation recess 14. That is, as shown in fig. 2, the bulge portion 53 has a shape corresponding to a part of a cylinder (for example, a semi-cylinder). The swash plate 50 has two bulging portions 53 arranged to be separated in the depth direction of the paper surface of fig. 1. The rotation shaft member 18 passes between the two bulging portions 53.

In this example, the accommodation recess 14 of the swash plate support portion 13 has a receiving surface 14a along an arc. On the other hand, the bulging portion 53 of the swash plate 50 has a sliding surface 53a along an arc. When the bulging portion 53 is disposed in the accommodation recess 14, the sliding surface 53a of the bulging portion 53 comes into contact, particularly, surface contact with the receiving surface 14a of the accommodation recess 14. The bulging portion 53 slides relative to the swash plate support portion 13 within the accommodation recess 14, and the bulging portion 53 rotates relative to the swash plate support portion 13 about the center of the arc defined by the receiving surface 14a and the sliding surface 53a as the pivot axis IA. The center axis IA of the yawing operation is not particularly limited, but may be located on the main surface 52 of the swash plate 50. With this configuration, the swash plate 50 is supported by the swash plate support portion 13 so that the inclination of the main surface 52 can be changed.

As shown in fig. 1, the hydraulic device 10 further includes a yaw adjustment mechanism (tilt adjustment mechanism) 35 for controlling the tilt of the main surface 52 of the swash plate 50. In the illustrated example, the yaw adjustment mechanism 35 includes a swash plate urging member 36 and an adjustment member 37. The following describes the structures of the yaw adjustment mechanism 35 and the swash plate 50 associated with the yaw adjustment mechanism 35.

The swash plate 50 shown in fig. 2 has a central portion 50a, a 1 st force receiving portion 50b, and a 2 nd force receiving portion 50 c. The central portion 50a is disposed between the 1 st force receiving portion 50b and the 2 nd force receiving portion 50 c. The central portion 50a is provided with the central through hole 51, the main surface 52, and the bulging portion 53. The 1 st force receiving portion 50b and the 2 nd force receiving portion 50c are portions extending from the central portion 50a to opposite sides, respectively.

The swash plate 50 is pressed by the swash plate biasing member 36 and the adjusting member 37 of the yaw adjusting mechanism 35, and the swash plate 50 is reversely deflected. The swash plate 50 is held at a certain deflection position by balancing the force pressed by the swash plate urging member 36 and the force pressed by the adjustment member 37. In the illustrated example, the swash plate biasing member 36 contacts the 1 st force receiving portion 50b of the swash plate 50 to press the swash plate 50 so as to deflect the swash plate 50 counterclockwise in fig. 1. The adjustment member 37 contacts the 2 nd force receiving portion 50c of the swash plate 50 to press the swash plate 50 to deflect the swash plate 50 clockwise in fig. 1.

The swash plate urging member 36 is supported by the 1 st housing block 15a of the housing 15. The swash plate urging member 36 is formed of, for example, a compression spring. Thus, the swash plate urging member 36 presses the swash plate 50 with an elastic force corresponding to the deformation force thereof.

On the other hand, the adjustment member 37 is configured as an adjustment actuator 38 and has a control piston 39. The control piston 39 can approach (advance) and separate (retreat) from the swash plate 50 in a direction parallel to the rotation axis RA of the rotary shaft member 18. The control piston 39 presses the 2 nd force receiving portion 50c of the swash plate 50. The control piston 39 is driven, for example, hydraulically. Further, the force with which the control piston 39 presses the 2 nd force receiving portion 50c can be adjusted. Therefore, by causing the control piston 39 to push the 2 nd force receiving portion 50c of the swash plate 50 with a greater force, the swash plate 50 is raised from the state shown in fig. 1, and the inclination angle of the main surface 52 with respect to the plane perpendicular to the rotation axis RA can be reduced. Further, by causing the control piston 39 to press the 2 nd force receiving portion 50c of the swash plate 50 with a smaller force, the swash plate 50 is further inclined from the state shown in fig. 1, and the inclination angle of the main surface 52 with respect to the plane perpendicular to the rotation axis RA can be increased. The swash plate 50 can be held in a predetermined tilted posture by balancing the force pressing the 2 nd force receiving portion 50c by the control piston 39 and the force pressing the 1 st force receiving portion 50b by the swash plate biasing member 36.

However, as shown in fig. 1, the control piston 39 of the adjustment member 37 is not in direct contact with the swash plate 50. The piston head 39a of the control piston 39 contacts the shaft-like member 40, and presses the swash plate 50 via the shaft-like member 40. The shaft-like member 40 is held by the swash plate 50. The portion that comes into contact with the control piston 39 and is pressed by the adjustment member 37 needs to be a high-hardness component with little abrasion or thermal adhesion. By using the shaft-like member 40 having a hardness higher than the hardness of the swash plate 50, it is possible to avoid making the entire swash plate 50 have a high hardness. Further, by using the high-strength shaft-like member 40, the manufacturing cost of the hydraulic device 10 can be made significantly lower than when the entire swash plate 50 is quenched or when the entire swash plate 50 is formed of a high-hardness material. For example, by manufacturing the swash plate 50 as a casting and using the shaft-like member 40 having a simple shape as a quenched component, it is possible to significantly reduce the manufacturing cost as compared with the case where the swash plate 50 is entirely made of a quenched component.

On the other hand, when the shaft member 40 separate from the swash plate 50 is used, it is naturally necessary to avoid the shaft member 40 from coming off during use of the hydraulic apparatus 10. That is, the shaft-like member 40 needs to be stably held by the swash plate 50. In the present embodiment, a study is made to prevent the shaft member 40 from coming off while suppressing an increase in the size of the swash plate. This study is discussed in detail below.

As shown in fig. 2, the swash plate 50 has a groove portion 55. The shaft-like member 40 is disposed in the groove portion 55 and held in the groove portion 55. The shaft-like member 40 may be a columnar member having an axial direction da, or a shape obtained by chamfering a columnar body. The axial direction da of the shaft-like member 40 is along the height direction of the column of the shaft-like member 40.

In the illustrated example, the shaft-like member 40 has a cylindrical-based shape. As shown in fig. 2, when the shaft-like member 40 having a cylindrical shape or a shape obtained by chamfering a cylindrical shape is held by the swash plate 50 such that the axial direction da thereof is parallel to the tilt axis IA of the swash plate 50, the piston head 39a of the control piston 39 can smoothly slide on the shaft-like member 40 at the time of tilting of the swash plate 50. This stabilizes the swash plate 50 in the tilting operation.

In the illustrated example, the shaft-like member 40 has both end portions chamfered in the axial direction da. That is, when viewed from a direction orthogonal to the axial direction da, the shaft-like member 40 has curved side surfaces 41 at both ends in the axial direction da.

In the illustrated example, as described above, the groove portion 55 for housing the swash plate 50 of the shaft-like member 40 is provided in the 2 nd force receiving portion 50 c. As shown in fig. 2, the groove portion 55 extends in a direction parallel to the yaw axis IA of the swash plate 50. Thus, the groove length direction d1 is orthogonal to the direction in which the control piston 39 of the adjustment member 37 is pressed. In the illustrated example, the groove portions 55 are open at both ends of the groove portion 55 in the longitudinal direction d1 parallel to the yaw axis IA. That is, the groove portion 55 extends so as to penetrate the swash plate 50 in a direction parallel to the yaw axis IA. As a result, the groove 55 has: a pair of both-end openings 55a located at both ends of the groove portion 55 in the longitudinal direction d 1; and an upper opening 55b located between the pair of both-end openings 55 a. The groove portion 55 further includes: a 1 st side wall 60A and a 2 nd side wall 60B which are opposed along a width direction d2 orthogonal to the groove length direction d 1; and a bottom wall 70 extending between the 1 st side wall 60A and the 2 nd side wall 60B. The groove 55 is defined by a side wall surface 65 formed by the side wall 60 and a bottom wall surface 75 formed by the bottom wall 70.

Preferably, the shaft-like member 40 is fitted into and held in the groove portion 55. Specifically, the shaft-like member 40 may be fixed to the swash plate 50 by interference fit. In the illustrated example, the shaft-like member 40 has a circular shape in a cross section orthogonal to the axial direction da thereof. As shown in fig. 5, the depth Dx of the groove portion 55 is larger than half of the maximum diameter Dy of the shaft-like member 40 and smaller than the maximum diameter Dy of the shaft-like member 40. Therefore, the shaft-like member 40 is interference-fitted with the groove portion 55 at the portion having the largest diameter, and the shaft-like member 40 can be stably held by the swash plate 50. In addition, a part of the shaft-like member 40 is exposed to the outside of the groove portion 55, and stable contact between the shaft-like member 40 and the control piston 39 can be ensured. From the viewpoint of more effectively ensuring such an action and effect, it is effective that the depth Dx of the groove portion 55 is 55% to 75% of the maximum diameter Dy of the shaft-like member 40 orthogonal to the axial direction da.

In this example, the shaft-like member 40 is not covered with the swash plate 50 from both outer sides in the longitudinal direction d1 of the groove portion 55. With this configuration, the dimension of the 2 nd force receiving portion 50c of the swash plate 50 along the groove longitudinal direction d1 can be reduced. This effectively suppresses the increase in size of the swash plate 50 and the hydraulic device 10, and further, the swash plate 50 and the hydraulic device 10 can be reduced in size.

In addition, in this example, the shaft-like member 40 is effectively restricted from moving relative to the swash plate 50 in a direction non-parallel to the axial direction da thereof by the pair of side walls 60 and the bottom wall 70, and the piston head 39a of the control piston 39. However, depending on the operating conditions of the hydraulic device 10, the use environment, manufacturing errors, assembly errors, and the like of the elements constituting the hydraulic device 10, a force may act to move the shaft-like member 40 in the groove longitudinal direction d1 with respect to the swash plate 50. When the shaft-like member 40 moves in the groove portion 55 in the groove longitudinal direction d1, the shaft-like member 40 may fall off the swash plate 50.

Further, it is envisioned that: the movement of the shaft-like member 40 in the groove length direction d1 in the groove portion 55 is restricted to some extent by using a fastener such as a retaining ring or a bolt. However, the work of fixing the shaft-like member 40 in the groove portion 55 using the fastener is complicated, and the manufacturing cost is increased, which is not preferable, and there is a possibility that the fastener itself falls off from the swash plate 50 to hinder the sound operation of the hydraulic device 10.

In view of this, in the hydraulic apparatus 10 of the present embodiment, the groove portion 55 includes: a central portion 55c for holding the shaft-like member 40; and narrow portions 55d located on both sides of the central portion 55c and having a width smaller than that of the central portion 55 c. That is, the narrow portions 55d are provided on both sides of the central portion 55c along the groove longitudinal direction d 1. The width Wx of the groove portion 55 in the groove width direction d2 at the narrow-width portion 55d is narrower than the width Wx of the groove portion 55 in the groove width direction d2 at the central portion 55 c. Further, a width Wx of the narrow-width portion 55d along the groove width direction d2 is narrower than a maximum diameter Dy of the shaft-like member 40 orthogonal to the axial direction da of the shaft-like member 40. That is, the groove portion 55 has a narrow portion 55d whose width Wx is narrowed, and the narrow portion 55d is located outside the central portion 55c along the groove longitudinal direction d1, that is, on a side away from the center of the groove longitudinal direction d1 along the groove longitudinal direction d 1. The shaft-like member 40 can be effectively restricted from moving relative to the swash plate 50 in the groove longitudinal direction d1 by contact or interference between the narrow portion 55d of the groove portion 55 and the shaft-like member 40. This can effectively prevent the shaft-like member 40 from coming off the groove 55. In particular, by making the groove width Wx at both end portions in the groove longitudinal direction d1 narrower than the maximum diameter Dy of the shaft-like member 40 orthogonal to the axial direction da, the shaft-like member 40 can be effectively prevented from coming off the groove portion 55 in the axial direction da.

In the illustrated example, the width Wx of the groove portion 55 along the groove width direction d2 is narrowed at both ends in the groove longitudinal direction d 1. That is, the narrow portions 55d are located at both ends of the groove portion 55. In particular, the groove width Wx at both ends in the groove longitudinal direction d1 is narrower than the maximum diameter Dy of the shaft-like member 40 orthogonal to the axial direction da.

Here, the groove portion 55 will be discussed in further detail based on a plurality of specific examples. First, an example of the groove 55 will be described in further detail mainly with reference to fig. 3 to 5.

In the example shown in fig. 3 to 5, each side wall 60 defining the groove portion 55 has a protruding portion 62 that protrudes in the groove width direction d2 to form a narrow portion 55 d. In particular, in the illustrated example, the projecting portion 62 includes a 1 st projecting portion 62A and a 2 nd projecting portion 62B which are respectively located at both end portions of the groove portion 55 in the groove longitudinal direction d 1. The 1 st protruding portion 62A and the 2 nd protruding portion 62B extend along the depth direction d3 of the groove portion 55. Each of the projections 62 has the 1 st and 2

nd portions

63a, 63b arranged along the depth direction d3 of the groove portion 55. The 1 st portion 63a thereof is located on the side of the bottom wall 70 in the depth direction d 3. In particular, in the illustrated example, the 1 st portion 63a is connected to the bottom wall 70. As shown in fig. 5, the projection length Lx1 in the depth direction d3 of the 1 st segment 63a of the groove 55 connected to the bottom wall 70 is longer than the projection length Lx2 in the width direction of the 2 nd segment 63 b.

In the example of the groove portion 55 shown in fig. 3 to 5, the groove portion 55 includes curved sidewalls (sidewall curved surfaces 67) at both ends in the groove longitudinal direction d 1. The protrusion 62 forms a curved sidewall (sidewall curved surface 67). As shown in fig. 4, the side wall curved surface 67 is positioned so as to face the curved side surface 41 of the shaft-like member 40 in the groove longitudinal direction d 1.

Further, in another expression, the sidewall surface 65 formed by each sidewall 60 has a shape obtained by cutting out the sidewall recess 64 from a flat surface parallel to both the longitudinal direction d1 and the depth direction d 3. In the illustrated example, each of the side wall surfaces 65 includes: a sidewall base 66 and a sidewall web 68 parallel to both the length direction d1 and the depth direction d 3; a sidewall curvature 67 between the sidewall base 66 and the sidewall relief 68; and a sidewall step surface 69 that connects the sidewall web 68 and the sidewall curved surface 67. The side wall curved surface 67, the side wall reduced surface 68, and the side wall step surface 69 are connected to respective ends in the groove length direction d 1. Sidewall curvature 67, sidewall taper 68, and sidewall step 69 are formed by tab 62. The side wall rebate 68 is located inwardly of the side wall base 66 in the width direction d 2. The side wall step surface 69 faces the depth direction d3 similarly to the bottom wall surface 75.

The groove portion 55 shown in fig. 3 to 5 can be produced by substantially the same amount of work as a normal groove. That is, the groove 55 shown in fig. 3 to 5 can be produced without a significant increase in cost. An example of a method for forming the groove 55 shown in fig. 3 to 5 will be described with reference to fig. 6 to 9.

For example, the groove portion 55 can be produced by performing cutting processing using a machine tool on the swash plate 50. As a tool used for the cutting process, an end mill 91 can be used. When the groove portion 55 is formed using a cutting tool, the cutting tool is usually passed through the swash plate 50 as a workpiece a plurality of times. In the manufacturing method shown in fig. 6 to 9, the relative position of the cutting tool with respect to the workpiece to be processed on which the swash plate 50 is to be formed is changed in two stages of cutting, i.e., the first cutting and the second cutting.

First, in the first cutting process shown in fig. 6 and 7, the groove portion 56 extending linearly is formed so as to cross the swash plate 50. By using the end mill 91, the side wall surface and the bottom wall surface of the groove portion become flat surfaces. Fig. 6 shows the swash plate 50 as viewed from the same direction as fig. 4, and fig. 7 shows the swash plate 50 as viewed from the rear along the direction in which the end mill 91 moves during cutting.

Next, as shown in fig. 8 and 9, a second cutting process is performed. As shown in fig. 8, the diameter of the end mill 91 used in the second cutting is slightly larger than the diameter of the end mill 91 used in the first cutting. As shown in fig. 9, in the second cutting, the depth of the end mill 91 in the depth direction d3 is slightly larger than that in the first cutting. In fig. 7, the end mill 91 in the first cutting process is indicated by a solid line, and the end mill 91 in the second cutting process is indicated by a two-dot chain line. In the second cutting process, the end mill 91 does not cross the shaft-like member 40 along the groove longitudinal direction d 1. The feed range of the end mill 91 in the groove longitudinal direction d1 is set only between the positions of the two end mills 91 indicated by the two-dot chain line in fig. 8. By reducing the feeding range in the groove longitudinal direction d1 in this manner, the protruding portion 62 is left.

By the cutting process shown in fig. 6 to 9, the side wall base surface 66, the side wall curved surface 67, and the bottom wall surface 75 of the side wall surface 65 of the groove portion 55 shown in fig. 3 are cut by the second cutting process. On the other hand, the side wall tapered surface 68 and the side wall stepped surface 69 of the side wall surface 65 of the groove portion 55 shown in fig. 3 are surfaces cut by the first cutting.

In the above description, the size of the cutting tool is changed between the first cutting and the second cutting, but the present invention is not limited to this example. For example, although the same size cutting tool is used for the first cutting and the second cutting, the cutting tool may be moved not only in the groove longitudinal direction d1 but also in the groove width direction d2 in the second cutting. Similarly, in the first cutting process, the cutting tool may be moved not only in the groove longitudinal direction d1 but also in the groove width direction d 2. According to such a method, the groove 55 having a desired size can be produced using a cutting tool having a small diameter smaller than the width Wx of the groove 55 to be produced.

Next, another example of the groove 55 will be discussed in further detail mainly with reference to fig. 10 to 12.

In the example shown in fig. 10 to 12, each side wall 60 defining the groove 55 has: the 1 st projecting portion 62A and the 2 nd projecting portion 62B provided at both end portions in the groove longitudinal direction d1, respectively, and the 3 rd projecting portion 62C provided between the 1 st projecting portion 62A and the 2 nd projecting portion 62B are taken as the projecting portions 62. The 1 st protruding portion 62A and the 2 nd protruding portion 62B extend along the depth direction d3 of the groove portion 55. The 3 rd protruding portion 62C is connected to the bottom wall 70 of the groove portion 55 and extends along the longitudinal direction d1 of the groove portion 55. In the example shown in fig. 10 to 12, the groove portion 55 also includes curved side walls (side wall curved surfaces 67) at both ends in the groove longitudinal direction d 1. The 1 st projection 62A and the 2 nd projection 62B form a side wall (side wall curved surface 67) having such a curved surface. As shown in fig. 11, the side wall curved surface 67 is positioned so as to face the curved side surface 41 of the shaft-like member 40 in the groove longitudinal direction d 1.

In the example shown in fig. 10 to 12, the side wall surface 65 formed by each side wall 60 also has a shape obtained by cutting out the side wall recess 64 from a flat surface parallel to both the longitudinal direction d1 and the depth direction d 3. In the illustrated example, each of the side wall surfaces 65 includes: a sidewall base 66 and a sidewall web 68 parallel to both the length direction d1 and the depth direction d 3; and a sidewall curvature 67 and a sidewall step 69 between the sidewall base 66 and the sidewall web 68. The side wall rebates 68 are located inwardly of the width direction d2 compared to the side wall base surfaces 66. Sidewall curvature 67, sidewall taper 68, and sidewall step 69 are formed by tabs 62A, 62B, 62C. The side wall beads 68 formed by the projections 62A, 62B are provided at each end in the groove length direction d1 and extend in the groove depth direction d 3. The side wall step surface 69 formed by the projection 62C is connected to the bottom wall 70 and extends along the groove length direction d 1. The side wall step surface 69 faces the depth direction d3 similarly to the bottom wall surface 75.

The groove portions 55 shown in fig. 10 to 12 can be produced by two-stage cutting in the same manner as the groove portions 55 shown in fig. 3 to 5. The first cutting process may be performed in the same manner as the first (first stage) cutting process for forming the groove portion 55 of fig. 3 to 5 described with reference to fig. 6 and 7.

The second cutting process uses an end mill 91b (see the two-dot chain line in fig. 12) having a diameter slightly larger than that of the end mill 91a (see the two-dot chain line in fig. 12) used in the first cutting process. As shown in fig. 12, in the second cutting, the depth of the end mill 91b in the depth direction d3 is slightly smaller than that in the first cutting. By reducing the cut amount in the groove depth direction d3 in this manner, the 3 rd projecting portion 62C remains.

The feed range in the groove longitudinal direction d1 of the end mill in the second cutting process is performed in the same manner as the second cutting process for producing the groove portion 55 in fig. 3 to 5 described with reference to fig. 8. That is, in the second cutting process, the end mill does not cross the shaft-like member 40 along the groove longitudinal direction d 1. The feed range of the end mill 91 in the groove longitudinal direction d1 is set only between the positions of the two end mills 91 shown by the two-dot chain line in fig. 8. By reducing the feeding range in the groove longitudinal direction d1 in this manner, the 1 st projecting portion 62A and the 2 nd projecting portion 62B remain.

By the above cutting, the side wall base surface 66, the side wall curved surface 67, and the side wall stepped surface 69 of the side wall surface 65 of the groove portion 55 shown in fig. 10 are cut by the second cutting. On the other hand, the side wall tapered surface 68 and the bottom wall surface 75 of the side wall surface 65 of the groove portion 55 shown in fig. 10 are surfaces cut by the first cutting.

In the above description, the size of the cutting tool is changed between the first cutting and the second cutting, but the present invention is not limited to this example, and the cutting tool having the same size may be used for the first cutting and the second cutting in the same manner as the groove forming method of fig. 3 to 5. In the first cutting and the second cutting, the cutting tool may be moved not only in the groove longitudinal direction d1 but also in the groove width direction d 2.

Fig. 13 shows another example of the groove 55. As in the example shown in fig. 13, the protruding portion 62 in which the width Wx of the groove portion 55 is narrowed may be provided only on one of the 1 st side wall 60A and the 2 nd side wall 60B. In the example shown in fig. 13, only the 1 st side wall 60A has the protruding portion 62. The 1 st side wall 60A shown in fig. 13 is configured in the same manner as the 1 st side wall 60A of the groove portion 55 shown in fig. 3 to 5. In the example shown in fig. 13, the 2 nd side wall 60B may be formed as a flat surface parallel to both the groove longitudinal direction d1 and the groove depth direction d 3.

In the above-described embodiment, the hydraulic apparatus 10 includes: a swash plate 50; a swash plate support portion 13 that supports the swash plate 50; a shaft-like member 40 held in a groove portion 55, the groove portion 55 being formed in the swash plate 50; and an adjusting member 37 that adjusts the inclination of the swash plate 50 by pressing the shaft-like member 40. Further, the groove portion 55 can effectively restrict the movement of the shaft-like member 40 in the longitudinal direction d1 of the groove portion 55 by the change in the width Wx of the groove portion 55 including the central portion 55c for holding the shaft-like member 40 and the narrow portions 55d located on both sides of the central portion 55c and having a width smaller than the width of the central portion 55 c. This enables the shaft-like member 40 to be stably held by the swash plate 50, and the shaft-like member 40 can be effectively prevented from coming off the swash plate 50. Therefore, according to the present embodiment, in the hydraulic apparatus 10 having the swash plate 50, the reliability of the hydraulic apparatus 10 can be improved and the life of the hydraulic apparatus 10 can be prolonged by effectively preventing the shaft-like member 40 from coming off while suppressing the increase in size of the swash plate 50 and the hydraulic apparatus 10.

As described above, the groove portion 55 can be manufactured with a work load equivalent to that of a normal groove portion by cutting using an end mill (tool) 91 as an example of a widely-used flat-tipped machining tool as a method for manufacturing the normal groove portion 55. In this regard, the manufacturing costs of the useful swash plate 50 and the hydraulic device 10 can be effectively reduced.

In some of the above-described specific examples, the groove portion 55 for holding the shaft-like member 40 is open at both ends in the longitudinal direction d1 that coincides with the axial direction da of the shaft-like member 40. That is, the shaft-like member 40 is not covered from both outer sides in the axial direction da. Therefore, the swash plate 50, more specifically, the swash plate along the longitudinal direction d1 of the groove portion 55 can be effectively prevented from being increased in size.

In some of the above-described specific examples, the portions where the width of the groove portion 55 is narrowed are both end portions of the groove portion 55. According to such an example, the size of the swash plate along the longitudinal direction d1 of the groove portion 55 can be more effectively suppressed from increasing.

In some of the above-described specific examples, the groove portion 55 includes curved sidewalls 60 at both ends. According to such a specific example, the curved side wall 60 can contact the shaft-like member 40 to restrict the movement of the shaft-like member 40 in the axial direction da. By forming the side wall 60 in contact with the shaft-like member 40 in a curved shape, stress concentration on the side wall 60 can be effectively prevented. This can more effectively improve the reliability and prolong the life of the hydraulic device 10.

In some of the above-described specific examples, the shaft-like member 40 has curved side surfaces 41 at both ends thereof. According to such a specific example, the curved side wall 60 (side wall curved surface 67) of the groove portion 55 and the curved side surface 41 of the shaft-like member 40 face each other in the axial direction da of the shaft-like member 40, whereby the contact area between the narrowed side wall 60 of the groove portion 55 and the shaft-like member 40 can be increased. This can more effectively prevent the shaft-like member 40 from moving in the axial direction da, and can effectively prevent a large force from locally acting on the side wall 60 and the shaft-like member 40. This can more effectively improve the reliability and prolong the life of the hydraulic device 10.

In some of the above-described specific examples, the swash plate 50 has the protruding portions 62, and the protruding portions 62 are provided at both ends of the groove portion 55 and protrude into the groove portion 55. By using such a projection 62, the movement of the shaft-like member 40 in the axial direction da can be more effectively prevented.

In some of the above-described specific examples, the protruding portion 62 forms the side wall 60 having a curved surface. By using such a projection 62, the movement of the shaft-like member 40 in the axial direction da can be more effectively prevented.

In the specific example described with reference to fig. 3 to 5, the protrusion 62 includes the 1 st segment 63a and the 2 nd segment 63b arranged along the depth direction d3 of the groove 55. The projection length Lx1 in the width direction d2 of the 1 st part 63a of the groove part 55 connected to the bottom wall 70 is longer than the projection length Lx2 in the width direction d2 of the 2 nd part 63b of the groove part 55. In this specific example, the width of the bottom wall 70 in the groove width direction d2 also varies along the groove length direction d 1. Further, since the projection length Lx1 in the groove width direction d2 of the 1 st portion 63a of the groove portion 55 continuous with the bottom wall 70 is long, the width of the bottom wall 70 in the groove width direction d2 greatly changes along the groove length direction d 1. Thus, it is possible to make it difficult for the swash plate 50 to be deformed, and the groove portion 55 is opened, in other words, the 1 st side wall 60A and the 2 nd side wall 60B facing in the width direction d2 of the groove portion 55 are away from each other. This can more effectively prevent the shaft-like member 40 from coming off.

In the specific example described with reference to fig. 10 to 12, the swash plate 50 includes: a 1 st protruding portion 62A and a 2 nd protruding portion 62B which are provided at both ends of the groove portion 55, respectively, and protrude into the groove portion 55; and a 3 rd protruding portion 62C provided between the 1 st protruding portion 62A and the 2 nd protruding portion 62B and protruding into the groove portion 55. The 3 rd protruding portion 62C is connected to the bottom wall 70 of the groove portion 55 and extends along the longitudinal direction d1 of the groove portion 55. According to this specific example, the sidewall recess 64 formed in the sidewall 60 can be reduced in size. In other words, many projections 62 are formed so as not to interfere with the shaft-like member 40. This can improve the rigidity of the swash plate 50 including the groove portion 55, and can effectively suppress deformation of the swash plate 50 which causes the shaft-like member 40 to fall off.

One embodiment is described with reference to a plurality of specific examples, but these specific examples are not intended to limit the one embodiment. The above-described embodiment can be implemented in various other specific examples, and various omissions, substitutions, and changes can be made without departing from the spirit thereof.

An example of the modification is described below with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for corresponding portions in the above-described specific example are used for portions that can be configured similarly to the above-described specific example, and overlapping description is omitted.

In the above-described example, the shaft-like member 40 has the curved side surfaces 41 at both ends in the axial direction da, but the present invention is not limited to this example. As shown in fig. 14, the shaft-like member 40 may be chamfered at both ends in the axial direction da to form a shape other than a curved shape. The shaft-like member 40 may not be chamfered. As described above, the shaft-like member 40 may have a prism shape or a shape obtained by chamfering a prism.

In the above-described specific example, the narrow portions 55d are formed at both ends of the groove portion 55, but the present invention is not limited thereto. The narrow portion 55d may be located between the end portion of the groove portion 55 and the central portion 55c along the groove longitudinal direction d 1.

In the above-described specific example, the groove 55 is open at both ends, but the present invention is not limited to this. At least one end of the groove portion 55 may be closed.

Claims

1. A hydraulic device, wherein,

the hydraulic device is provided with:

a piston;

a swash plate disposed opposite to the pistons;

a shaft-like member held in a groove portion provided in the swash plate;

a swash plate support portion that supports the swash plate; and

2. A hydraulic device is provided with: a sloping plate; a swash plate support portion that supports the swash plate; a shaft-like member held in a groove portion formed in the swash plate; and an adjusting member that adjusts the inclination of the swash plate by pressing the shaft-like member, wherein,

3. A hydraulic device, wherein,

the hydraulic device is provided with:

a shaft-like member held at the central portion of the groove portion;

a swash plate support portion that supports the swash plate; and

4. The hydraulic apparatus according to any one of claims 1 to 3,

the groove portion includes curved side walls at both ends.

5. The hydraulic apparatus of claim 4,

the shaft-shaped member has curved side surfaces at both ends of the shaft-shaped member.

6. The hydraulic apparatus according to any one of claims 1 to 3,

the groove portion is open at both ends.

7. A swash plate with a shaft-like member for a hydraulic device, wherein,

the swash plate with a shaft-like member includes:

a swash plate disposed opposite to the piston; and

8. A swash plate with a shaft-like member for a hydraulic device, wherein,

the swash plate with a shaft-like member includes:

9. A swash plate for a hydraulic device, which is disposed opposite to a piston, wherein,