CN1751555B - Paddy field working machine - Google Patents

Abstract

The present invention provides a paddy field working vehicle, which the left,right front wheel (1) or rear wheel (2) supports the vehicle by the suspending machine (260, 267), the power from the engine transmitted to the gear box (17) of the left, right and front wheel respectively, is fixed on the machine, and the storage material in the hopper feeding the output part (13) to the floor is supported in the machine body, the gearings (97, 105, 107) is set between the gear box (17) and the outpuet part (13).

Description

Paddy field working vehicle

Technical Field

The present invention relates to a paddy field work vehicle such as a riding type rice transplanter or a riding type direct seeder.

Background

As such a paddy field work vehicle, for example, as disclosed in japanese laid-open patent publication No. 2004-17934, japanese laid-open patent publication No. 2003-81140, and the like, there is a work vehicle in which the right and left front wheels or the right and left rear wheels are supported by the body via suspension mechanisms, and the traveling performance in a paddy field or on the road is improved.

As a paddy field work vehicle, there is a work vehicle configured to supply a storage material (for example, a powder or granule such as fertilizer or seed) in a hopper from an output portion to the ground through a supply portion (see japanese unexamined patent application publication No. 2004-17934). In this case, in order to drive the output portion, it is necessary to transmit power from the engine to the output portion.

Accordingly, a primary object of the present invention is to provide a paddy field working vehicle having a structure capable of more appropriately transmitting engine power to an output portion and improving power transmission efficiency to the output portion.

Disclosure of Invention

In order to achieve the above object, the present invention provides a paddy field working vehicle in which rear axle boxes supporting left and right rear wheels are supported on a machine body via suspension mechanisms, a transmission case for transmitting power from an engine to the left and right rear wheels is fixed to the machine body, and an output portion for supplying stored materials in a hopper to the ground is supported on the machine body, wherein a travel output shaft of the transmission case protrudes from the transmission case, a transmission shaft is connected to a protruding end portion thereof via a universal joint, and the power of the travel output shaft is transmitted to the rear axle boxes via the universal joint and the transmission shaft, and the power is transmitted from the travel output shaft to one end of a transmission mechanism for driving the output portion, and the other end of the transmission mechanism is connected to the output portion. With the above-described characteristic configuration, the positional relationship between the wheels corresponding to the suspension mechanism and the machine body is changed by the suspension mechanism provided between the left and right front wheels or the left and right rear wheels and the machine body. At this time, since the transmission case is fixed to the body, the positional relationship between the transmission case and the body does not change. In addition, since the output unit is also supported by the body, the positional relationship between the output unit and the body does not change. Therefore, the transmission mechanism frame is provided between the transmission case and the output portion, the positional relationship with the machine body of which does not change. Therefore, even if the positional relationship between the corresponding wheel and the machine body is changed by the suspension mechanism due to the unevenness of the ground or the like, the relative positional relationship between the transmission mechanism and the machine body is not changed. In this way, the power from the engine can be smoothly transmitted from the transmission to the output portion via the transmission mechanism without being hindered.

Therefore, by the transmission mechanism having a fixed relative positional relationship with the machine body, stable power transmission from the transmission case to the output portion is possible, and the transmission efficiency of the power transmitted to the output portion can be improved.

In order to achieve the above configuration, according to a preferred embodiment, the suspension mechanism is provided on each of the rear wheels, a rear axle box supporting each of the rear wheels is supported by the machine body via the suspension mechanism, and power from a travel output shaft of the transmission is transmitted to the rear axle box via a universal joint and a propeller shaft.

In the case where the rear axle box is supported by the machine body via the suspension mechanism, if the traveling output shaft protrudes from the transmission case and the transmission shaft is connected to the protruding end portion thereof via the universal joint, the power of the traveling output shaft is transmitted to the rear axle box and the power transmitted to the transmission mechanism is output from the traveling output shaft, the configuration has the following advantages.

That is, if the positional relationship between the rear axle box and the engine body changes, the positional relationship between the universal joint and the transmission shaft and the engine body also changes, and in contrast, the positional relationship between the travel output shaft and the engine body does not change because the travel output shaft is fixed to the transmission case. Therefore, according to the above configuration, the power for driving the output portion can be smoothly output from the travel output shaft whose positional relationship with the machine body does not change. Therefore, the transmission efficiency of the power transmitted to the output portion can be further improved.

Further, since the power transmitted to the output unit via the transmission mechanism is branched from the power to be transmitted from the power for traveling to the rear axle box and the rear wheels, the output unit is driven at a speed synchronized with the traveling speed of the machine body. That is, the output section is also driven at a high speed if the traveling speed of the machine body becomes a high speed, and is also driven at a low speed if the traveling speed of the machine body becomes a low speed. Thus, the amount of the powder or granule supplied to the ground per unit travel distance is substantially constant regardless of the travel speed of the body.

Further, if a clutch for transmitting and blocking power is provided in a portion of the transmission mechanism located in the vicinity of the travel output shaft, the transmission mechanism is fixed to the machine body, and therefore the positional relationship between the transmission mechanism and the machine body does not change. Since the clutch is also fixed on the machine body, the position relation between the clutch and the machine body is not changed. Thereby, the reliability of the transmission and cutoff operations of the clutch is further improved. Further, since the clutch is disposed at a position close to the transmission case, the operating system connected to the transmission case and the operating system connected to the clutch are disposed at positions close to each other. Therefore, it is easy to configure these operating systems to be compact, which is advantageous for simplification of the configuration and space saving of each operating system.

According to a preferred embodiment, the suspension mechanism is provided on each of the rear wheels, and a rear axle box for supporting each of the rear wheels is provided via the suspension mechanism, and the transmission mechanism is disposed between a support member passing through a machine body for supporting the rear axle box and the rear axle box. This configuration has the following advantages.

That is, when the rear axle box is supported by the support member of the engine body via the suspension mechanism, a small gap is generated between the support member of the engine body and the rear axle box. This gap can be effectively utilized to configure the transmission mechanism appropriately, so that it is advantageous in terms of space saving. In this configuration, the transmission mechanism is located above the rear axle box, so that the transmission mechanism is less likely to contact the ground, which contributes to prevention of damage to the transmission mechanism and improvement in durability.

According to a preferred embodiment, the suspension mechanism is provided on each of the rear wheels, a rear axle box for supporting each of the rear wheels is provided via the suspension mechanism, and the transmission mechanism is supported by a support member of a machine body for supporting the rear axle box. This configuration has the following advantages.

That is, the transmission mechanism is supported by the support member of the engine body in addition to the support member of the engine body via the suspension mechanism. This makes it possible to support both the rear axle box and the transmission mechanism on the support member of the engine body, which is a common member. Thus, although the positional relationship between the rear axle box and the engine body (or the support member of the engine body) varies depending on the suspension mechanism, the range of the variation can be relatively easily estimated from the relationship with the engine body (or the support member of the engine body). In this way, the transmission mechanism can be easily and appropriately arranged so as not to interfere with the rear axle box, and therefore, the positional relationship between the rear axle box and the transmission mechanism can be determined with high accuracy. In addition, it is not necessary to dispose the transmission mechanism too far from the rear axle boxes.

According to a preferred embodiment, the suspension mechanism is provided on each of the front wheels and each of the rear wheels. According to this configuration, each wheel is supported via the suspension mechanism. Thus, in an operating state (in the case of a riding type rice transplanter, for example, a rice transplanting operating state in which a driver sits on a driver's seat, fertilizer is stored in a hopper, rice seedlings are placed on the preliminary rice seedling placing table, and rice seedlings are placed on the rice seedling placing table of the rice transplanting device), the bottom plate of the driver can be maintained in a substantially horizontal state while absorbing well vibrations and the like transmitted from the ground to the wheels by the suspension mechanisms provided on the wheels. Therefore, a stable riding feeling can be obtained, and stable paddy field work can be performed.

According to a preferred embodiment, a limiting mechanism is provided for determining the limit of extension and the limit of retraction of the suspension mechanism, and the limiting mechanism is configured such that the operating stroke of the suspension mechanism toward the limit of retraction is greater than the operating stroke toward the limit of extension. This configuration has the following advantages.

That is, in general, a suspension mechanism is provided with a limiting mechanism that sets a position halfway through its operation stroke as a standard position and determines the operation limit in both the expansion and contraction directions from this position. At this time, if the operation stroke of the suspension mechanism toward the contraction limit is set to be larger than the operation stroke toward the extension limit by the limiting mechanism as in the present invention, the suspension mechanism can be contracted greatly even when the front wheel or the rear wheel rolls over a large convex portion. This is advantageous in maintaining the floor of the cab in a substantially horizontal state and providing a stable ride.

Further, if a shock absorbing mechanism is provided in addition to the above configuration to absorb shock when the suspension mechanism reaches the expansion limit and the contraction limit, the shock can be suppressed from being transmitted to the body, which is more advantageous.

According to a preferred embodiment, the suspension mechanism is provided on each of the rear wheels, and the paddy field working device is connected to the rear part of the machine body via an elevating mechanism so as to be able to be elevated from the ground, and a forced extension mechanism is provided for forcibly extending the suspension mechanism when the paddy field working device is raised to a height exceeding a predetermined height. This configuration has the following advantages, which will be described below with reference to a riding type rice transplanter as an example of a paddy field working vehicle.

A riding type rice transplanter generally includes a lifting mechanism for lifting and driving a rice transplanter (an example of a paddy field working machine) by supporting the rice transplanter at the rear of a machine body so as to be freely lifted. In general, a riding type rice transplanter advances by the driving forces of left and right rear wheels, and therefore, the front part of the machine body tends to be lifted by the driving reaction forces of the left and right rear wheels. However, when the riding type rice transplanter reaches the ridge, it is necessary to raise the rice transplanter from the ground to a large extent and turn the body. In this case, since the suppression effect by the seedling planting device does not exist, if the front portion of the body tends to be lifted by the driving reaction forces of the left and right rear wheels, the ground contact pressure of the left and right front wheels is lowered, and the body may not be smoothly turned.

In this regard, according to the above configuration of the present invention, if the rice transplanting apparatus is driven to ascend by the elevating mechanism and exceeds a predetermined height from the ground, the suspension mechanism is forcibly extended by the extension driving mechanism, the left and right rear wheels descend, and the ground contact pressure of the left and right rear wheels temporarily increases in the middle thereof. Thus, the rear part of the machine body is lifted, and the machine body is easily sunk to suppress a decrease in ground contact pressure of the left and right front wheels. Therefore, the driving force of the left and right rear wheels is smoothly transmitted to the plow, and the machine body can smoothly turn. This can improve the cornering performance.

Other features, configurations, and advantages will become apparent from the following description, which proceeds with reference to the accompanying drawings.

In the following description, the front-rear direction, the left-right direction, the lateral side surface, and the up-down direction with reference to the traveling machine body forward direction are referred to as "front-rear direction", "left-right direction", "lateral side surface", and "up-down direction", respectively.

Drawings

Fig. 1 is a left side view of the entire paddy field working vehicle according to embodiment 1 of the present invention, and is a view showing a riding type rice transplanter as an example of the paddy field working vehicle.

Fig. 2 is a plan view showing a transmission system for transmitting power to a rear axle box and left and right rear wheels.

Fig. 3 is a right side view showing a supporting structure of the rear axle box, a transmission system for transmitting power from the transmission to the rear axle box, and a transmission system for transmitting power from the transmission to the output portion.

Fig. 4 is a left side view showing a supporting structure of the rear axle box, a transmission system for transmitting power from the transmission to the rear axle box, and a transmission system for transmitting power from the transmission to the output portion.

Fig. 5 is a plan view showing a supporting structure of the rear axle box, a transmission system that transmits power from the transmission to the rear axle box, and a transmission system that transmits power from the transmission to the output unit.

Fig. 6 is a front view showing a supporting structure of the rear axle box, a transmission system for transmitting power from the transmission case to the output portion, and a transmission system for transmitting power from the transmission case to the rice transplanting device.

FIG. 7 is a cross-sectional top view of the transmission.

Fig. 8 is a cross-sectional top view of the vicinity of the inter-plant transmission in the transmission.

Fig. 9 is a vertical front view of the vicinity of the front wheel supporting portion.

Fig. 10 is a vertical right side view of the vicinity of the travel output shaft and the transmission case.

Fig. 11 is an overall plan view of the riding rice transplanter shown in fig. 1.

FIG. 12 is a plan view of the rice transplanter body.

Fig. 13 is a side view of the seedling placing table in a lowered closed working state.

Fig. 14 is a side view of the seedling placing table in a raised open management state.

Fig. 15 is a side view of the suspension coupling mechanism, the elevation adjustment mechanism, and the pivot coupling portion.

Fig. 16 is a front view of the elevation adjustment mechanism.

Fig. 17 is a plan view of the rod guide member of the adjustment rod.

Fig. 18 is a side view of a support roller arrangement portion of the suspension link mechanism.

Fig. 19(a) is a side view of the lower end side of the seedling placing table in a lowered closed working state, and fig. 19(b) is a side view of the lower end side of the seedling placing table in a raised open management state.

Fig. 20 is a side view of the seedling guide member.

Fig. 21 is a top view of the seedling guide member.

Fig. 22 is a sectional view taken along line XXII-XXII in fig. 20.

Fig. 23 is a longitudinal sectional view of the direction indicator.

Fig. 24 is a plan view of a bulb arrangement portion of the direction indicator.

Fig. 25 is a perspective view of the bulb and bulb support portion of the direction indicator.

Fig. 26 is a perspective view of the seedling placing table at the reinforcing bar arranging part.

FIG. 27 is a sectional view of the main frame of the rice transplanter body.

Fig. 28 is a left side view of the rear axle box support structure, the transmission system that transmits power from the transmission case to the rear axle box, and the transmission system that transmits power from the transmission case to the output portion in modification (1) of embodiment 1.

Fig. 29 is a side view of a support roller arrangement portion of a suspension connection mechanism in modification (2) of embodiment 1.

Fig. 30 is a side view of a support roller arrangement portion of a suspension connection mechanism according to modification (3) of embodiment 1.

Fig. 31 is a left side view of the entire paddy field working vehicle according to embodiment 2 of the present invention, and is a view showing a riding type rice transplanter as an example of the paddy field working vehicle.

Fig. 32 is a plan view showing a rear axle box and a transmission system for transmitting power to left and right rear wheels.

Fig. 33 is a plan view showing a support structure for left and right front wheel support boxes and a support structure for rear axle boxes.

Fig. 34 is a vertical front view of the vicinity of the front wheel supporting portion.

Fig. 35 is a side view showing a supporting structure of the rear axle box.

Fig. 36 is a rear view showing a support structure of the rear axle box.

Fig. 37 is a side view showing a supporting structure of a rear axle box in modification 1 of embodiment 2.

Fig. 38 is a side view showing a support structure for a rear axle box in modification 2 of embodiment 2.

Fig. 39 is a side view showing a supporting structure of a rear axle box in modification 3 of embodiment 2.

Detailed Description

Next, preferred embodiments of the present invention will be described based on a riding type rice transplanter as an example of a paddy field working vehicle (more specifically, a riding type paddy field working machine) with reference to the drawings.

[ 1 st embodiment ]

[ integral constitution of riding rice transplanter ]

In the riding rice transplanter shown in fig. 1, a link mechanism 3 and a hydraulic cylinder (an example of an elevating mechanism) 4 for driving the link mechanism 3 to ascend and descend are provided at the rear part of a machine body provided with left and right front wheels 1, left and right rear wheels 2, and a rice transplanting device (an example of a paddy field working device) 5 is supported at the rear part of the link mechanism 3.

As shown in FIG. 1, the rice transplanting apparatus 5 is provided with: a transmission case 6, a transplanting box 7 rotatably supported at the rear part of the transmission case 6, a pair of transplanting arms 8 provided at both ends of the transplanting box 7, a ground floating body 9, a seedling placing table 10, and the like. As a result, the seedling placing table 10 is driven to be fed horizontally and reciprocally, the seedling box 7 is driven to rotate, and the seedling arm 8 alternately takes out seedlings from the lower portion of the seedling placing table 10 and plants the seedlings on a field.

The fertilizer application device of the riding type rice transplanter is configured as shown in fig. 1 and 4. That is, in this fertilizer application device, an output portion 13 that outputs fertilizer (an example of a stored material) from a hopper 12 that stores the fertilizer is fixed to and supported by the body on the rear side of a driver seat 11 provided on a bottom plate 220 of the body. A hopper 12 is provided above the output portion 13. A blower 14 is provided below the driver seat 11. The ground float 9 is provided with a furrow opener 15 (corresponding to a supply portion), and a hose 16 is connected between the output portion 13 and the furrow opener 15. Thus, as the seedlings are planted, a predetermined amount of fertilizer is discharged from the hopper 12 through the discharging unit 13 at a time, the fertilizer is supplied to the furrow opener 15 through the hose 16 by the wind from the blower 14, and the fertilizer is supplied to the ground through the furrow opener 15.

Direct seeding may be performed by storing seeds in the hopper 12 instead of fertilizer, and supplying the seeds from the hopper 12 to the ground via the furrow opener 15 (in this case, the seedling planting device 5 is stopped).

Left and right pedal bases 236 connected to the base 220 are provided laterally outward of the left and right sides of the hood 244. Left and right preliminary seedling placing tables 237 are provided laterally outward of the left and right step bottom plates 236, and 3 preliminary seedling placing portions 237a are supported on the preliminary seedling placing tables 237 in the vertical direction.

[ supporting structure for front wheel and left rear wheel ]

As shown in fig. 1, 3, and 5, a transmission case 17 is fixed to a front portion of the machine body, and an engine 19 is supported by a support frame 18 coupled to the front portion of the transmission case 17. A left and right body frame 21 (corresponding to a body support member) having a square tube shape is connected to an upper portion of the rear portion of the transmission case 17 and extends rearward, and a reinforcing member 20 having a triangular shape in a side view is connected between the rear portion of the transmission case 17 and the left and right body frames 21.

As shown in fig. 1 and 5, the left and right front axle boxes 23 extend from the left and right lateral side surfaces of the transmission case 17, and cylindrical support portions 23a directed diagonally downward and forward (see the vertical axis P1) are provided at the end portions of the left and right front axle boxes 23. The front wheel support portions 24 that support the left and right front wheels 1 are supported by the support portions 23a of the left and right front axle boxes 23 so as to be rotatable about the vertical axis P1 and slidable in the direction of the vertical axis P1. As shown in fig. 2, 3, and 5, the steering arm 25 is supported at a lower portion of the transmission case 17 so as to be swingable about a vertical axis P8 and extends rearward, and a tie rod 26 is connected between the front wheel support portion 24 and the steering arm 25. As shown in fig. 1, a steering wheel 27 for swinging the steering arm 25 is provided, and the steering arm 25 is swung by the steering wheel 27 to steer the left and right front wheels 1.

As shown in fig. 3, 5, and 6, the rear axle boxes 28 are integrally formed, and the right and left rear wheels 2 are supported on the rear axle boxes 28. The vertically long left and right brackets 22 having a cross section of コ are fixed to the front portion of the rear axle box 28, and the left and right upper links 29 are supported so as to be vertically swingable around a lateral axis P2 of the upper portions of the left and right brackets 22 and extend forward, and are supported so as to be vertically swingable around a lateral axis P3 of the bracket 21a fixed to the intermediate portion of the left and right body frames 21.

As shown in fig. 3, 5, and 6, a support pin 31 is fixed to the lower portion of the left and right brackets 22 so as to face laterally outward, and the left and right lower links 30 are supported so as to be vertically swingable about a horizontal axis P4 of the support pin 31 and extend forward, and are supported so as to be vertically swingable about a horizontal axis P5 of the lower portion of the rear portion of the transmission case 17. Support portions 21b are fixed to the left and right body frames 21, support portions 31a are fixed to the support pins 31, and left and right suspension springs 32 (corresponding to suspension mechanisms) are mounted between the support portions 21b of the left and right body frames 21 and the support portions 31a of the support pins 31. As shown in fig. 5 and 6, the cross bar 34 is supported so as to be vertically swingable about a front-rear axis P6 at the rear ends of the left and right body frames 21, and is supported so as to be vertically swingable about a front-rear axis P7 at the right rear portion of the rear axle box 28.

As described above, the suspension mechanisms 267 of the left and right rear wheels 2 are constituted by the suspension springs 32 and the like. As a result, as shown in fig. 3, 5, and 6, the rear axle box 28 is supported by the suspension spring 32 so as to be vertically movable and rotatable, the position of the rear axle box 28 in the front-rear direction is determined by the left and right upper links 29 and the left and right lower links 30, and the position of the rear axle box 28 in the left-right direction is determined by the lateral link 34.

[ Power Transmission Structure for Forward wheel Transmission ]

As shown in fig. 5 and 7, a hydrostatic continuously variable transmission 33 is coupled to a lateral side portion on the left side of the transmission 17, and the power of the engine 19 is transmitted to the hydrostatic continuously variable transmission 33 via a transmission belt 35, and the power transmitted to the hydrostatic continuously variable transmission 33 is transmitted to a hydraulic pump 37 via a propeller shaft 36 as it is.

As shown in fig. 7, the power of the output shaft 33a of the hydrostatic continuously variable transmission 33 is transmitted to a transmission shaft 56 via a transmission gear 55, and a low-speed gear 57, a high-speed gear 58, and a transmission gear 59 are fixed to the transmission shaft 56. A shift gear 61 is externally fitted to a transmission shaft 60 arranged in parallel with the transmission shaft 56 in a spline structure so as to be rotatable and slidable integrally with the transmission shaft 60, and a transmission gear 62 is fixed to the transmission shaft 60. Thus, the power of the transmission shaft 56 is shifted in two stages of high and low by sliding the shift gear 61 and meshing the shift gear with the low gear 57 and the high gear 58, and is transmitted to the transmission shaft 60.

As shown in fig. 7 and 9, a pair of propeller shafts 63 are disposed in a butt joint between the transmission case 17 and the left and right front axle boxes 23, a differential transmission mechanism 64 is provided between the pair of propeller shafts 63, a transmission gear 65 fixed to a case 64a of the differential transmission mechanism 64 meshes with the transmission gear 62, and a bevel gear 66 is fixed to an end of the pair of propeller shafts 63. The cylindrical member 81 is fitted to the one transmission shaft 63 by a key structure, is rotatable and slidable integrally with the transmission shaft, and is engaged with an end portion of the case 64a of the differential transmission mechanism 64, whereby the differential transmission mechanism 64 can be locked.

As shown in fig. 9, a bevel gear 68 (upper side) and a support member 69 (lower side) are supported by the support portions 23a of the left and right front axle boxes 23 via a bearing 67, and the bevel gears 66, 68 are meshed with each other. The transmission shaft 70 is integrally rotatably and slidably fitted with a bevel gear 68 and a support member 69 via a spline structure, and a bevel gear 71 is fixed to a lower end of the transmission shaft 70.

As shown in fig. 9, the front wheel support portion 24 includes a front axle 72 for supporting the right (left) front wheel 1, a bevel gear 73 fixed to the front axle 72, and a cylindrical sleeve 74 fixed to an upper end of the front wheel support portion 24. The front wheel support 24 and the sleeve 74 are rotatably supported by the propeller shaft 70 via bearings 75, and a seal member 76 is provided between the support 23a of the left and right front axle boxes 23 and the sleeve 74, and the bevel gears 71 and 73 are meshed with each other. The support member 77 is in contact with the upper bearing 75, and the inner and outer suspension springs 40 are provided between the support members 69 and 77.

Thus, as shown in fig. 7 and 9, the power of the output shaft 33a of the hydrostatic continuously variable transmission 33 is transmitted to the left and right front wheels 1 via the propeller shafts 56, 60, the differential transmission mechanism 64, the propeller shafts 63, 70, and the front axle 72. The front wheel support 24 is supported by the support 23a of the left and right front axle boxes 23 so as to be rotatable about the longitudinal axis P1 and slidable in the direction of the longitudinal axis P1, and the suspension spring 40 acts by sliding in the direction of the longitudinal axis P1 with respect to the front wheel support 24.

As described above, the suspension mechanism (an example of a front wheel suspension mechanism) 260 of the left and right front wheels 1 is constituted by the support portions 23a of the left and right front axle boxes 23, the front wheel support portions 24, the coil springs 40, and the like.

[ Driving structure for rear wheel Transmission ]

As shown in fig. 2, 3, and 7, the travel output shaft 78 is provided at a lower portion of the rear portion of the transmission case 17 (slightly to the right of the left and right center CL of the machine body in plan view) and protrudes rearward, a bevel gear 79 fixed to the case 64a of the differential transmission mechanism 64 meshes with a bevel gear 80 fixed to the travel output shaft 78, a universal joint 82 is attached to an end portion of the travel output shaft 78, and a propeller shaft 84 is connected to the universal joint 82 via a cylindrical expansion joint 83 (which transmits power and allows sliding of the propeller shaft 84 with respect to the universal joint 82). At the front portion of the rear axle box 28 (slightly to the right of the left and right center CL of the body), the output shaft 38 projects forward, and the propeller shaft 84 and the input shaft 38 are connected together via a universal joint 82.

As shown in fig. 2, the rear axle box 28 is provided with a propeller shaft 39, and a bevel gear 38a fixed to the input shaft 38 meshes with a bevel gear 39a fixed to the propeller shaft 39. Left and right side clutches 41 of a friction multi-plate type are provided at left and right end portions of the propeller shaft 39, and a propeller shaft 42 is provided between the side clutches 41 and a rear axle 43 supporting the left and right rear wheels 2. As a result, as shown in fig. 2, 3, and 7, the power of the output shaft 33a of the hydrostatic continuously variable transmission 33 is transmitted to the right and left rear wheels 2 via the propeller shafts 56 and 60, the case 64a of the differential transmission 64, the travel output shaft 78, the input shaft 38, the propeller shaft 39, the right and left side clutches 41, and the propeller shaft 42.

As shown in fig. 7, a plurality of friction plates 44 are provided between the wall portion inside the transmission case 17 and the travel output shaft 78, and a disc-shaped operating member 45 is fitted onto the travel output shaft 78 so as to be relatively rotatable. The operation shaft 46 is rotatably supported so as to intersect the lower side of the travel output shaft 78, the intermediate portion 46a of the operation shaft 46 is formed in a half-moon shape in cross section, and the intermediate portion 46a of the operation shaft 46 is in contact with the rear end of the operation member 45. As described above, the friction plate 44, the operating member 45, the operating shaft 46, and the like constitute the brake 47, and the brake pedal (not shown) is mechanically linked to the operating shaft 46 and the hydrostatic continuously variable transmission 33.

Thus, when the brake pedal is depressed, the hydrostatic continuously variable transmission 33 is operated to the neutral stop position, the operating shaft 46 is rotated and rotated by a predetermined angle in the clockwise direction in fig. 7, the operating member 45 is pressed upward in fig. 7 by the intermediate portion 46a of the operating shaft 46, and the operating member 45 presses the friction plate 44, so that the brake 47 is operated to the braking side. As shown in fig. 2, 7, and 9, when the brake 47 is operated to the braking side, the left and right front wheels 1 are braked via the differential transmission mechanism 64 and the propeller shafts 63 and 70, and the left and right rear wheels 2 are braked via the travel output shaft 78, the propeller shaft 84, the input shaft 38, the propeller shaft 39, the left and right side clutches 41, and the propeller shaft 42.

As shown in fig. 2, the left and right side clutches 41 are biased to a transmission state by a spring (not shown), left and right operation arms 51 are provided for operating the left and right side clutches 41 to a blocking state, and a connecting rod 53 is connected between the steering arm 25 and the left and right operation arms 51. The state shown in fig. 2 is a state in which the right and left front wheels 1 are steered to the straight-ahead position a0 and the right and left side clutches 41 are operated to the power transmitting state, and power is transmitted to the right and left front wheels 1 and the right and left rear wheels 2. Even if the left and right front wheels 1 are steered between the straight-ahead position a0 and the left-right set angle a1, the state described above is achieved, and the body is steered straight, or gently to the right or left.

As shown in fig. 2, when the left and right front wheels 1 are steered between the right set angle a1 and the right operation limit a2, the right connecting rod 53 is pulled by the steering arm 25, the right side clutch 41 is operated to the blocked state by the right operation arm 51, and the right rear wheel 2 is set to the free rotation state. In this case, the left side brake 41 is kept in the power transmission state, and the power is still transmitted to the left rear wheel 2. When the left and right front wheels 1 are steered between the left set angle a1 and the left operation limit a2, the left connecting rod 53 is pulled by the steering arm 25, the left side clutch 41 is operated to the disengaged state by the left operation arm 51, and the left and right rear wheels 2 are in the free rotation state. In this case, the right side brake 41 is kept in a power transmission state, and power is still transmitted to the right rear wheel 2.

In this way, when the left and right front wheels 1 are steered between the right set angle a1 and the right steering limit a2 or between the left set angle a1 and the left steering limit a2, the following states are achieved: the power is transmitted to the right and left front wheels 1 and the rear wheels 2 on the turning outer side, and the power transmitted to the rear wheels 2 on the turning center side is blocked, so that the rear wheels 2 on the rotation center side are in a freely rotatable state, thereby performing a right turn or a left turn. Thus, the rear wheel 2 on the turning center side is in a state of rotating appropriately and advancing straight along with turning, and the problem of ground damage caused by the rear wheel 2 on the turning center side during turning is reduced.

[ Power Transmission Structure for Transmission to transplanting device ]

As shown in fig. 7 and 8, the transmission gear 48 and the 6 transmission gears 49 are connected to each other to rotate integrally, the transmission gear 48 and the 6 transmission gears 49 are relatively rotatably fitted around the transmission shaft 60, and the transmission gears 48 and 59 mesh with each other. A drive shaft 50 disposed in parallel with the drive shaft 60 is externally fitted with 6 speed change gears 52 in a freely rotatable manner, and an operation lever 54 is provided for engaging each of the 6 pairs of gears 49 and 52, selecting one speed change gear 52 and freely connecting it to the drive shaft 50 or disconnecting it from the drive shaft 50. As described above, the inter-plant transmission 85 is configured by the 6 pairs of gears 49 and 52, the operating lever 54, and the like, and the power of the transmission shaft 60 is transmitted to the transmission shaft 50 by selecting one transmission gear 52 of the 6 transmission gears 52 by the operating lever 54 and connecting it to the transmission shaft 50.

As shown in fig. 5 and 8, an output shaft 86 is provided at a lower portion of the rear portion of the transmission case 17 (a position of the left and right center CL of the body in plan view), protrudes rearward, and a bevel gear 87 fitted onto the output shaft 86 so as to be relatively rotatable is engaged with a bevel gear 88 fixed to the propeller shaft 50. The shifting member 89 is externally fitted to the output shaft 86 by a spline structure, is rotatable and slidable integrally with the output shaft 86, and is provided with a spring 90 for biasing the shifting member 89 to the side meshing with the bevel gear 87, and is provided with an operating lever 91 for operating the shifting member 89 to be away from the bevel gear 87, thereby constituting a seedling planting clutch 92 for freely transmitting and blocking the power of the transmission shaft 50 to the output shaft 86.

As shown in fig. 1, 5, and 6, a transmission shaft 93 is connected to the output shaft 86 and extends rearward, and is disposed at the left and right center CL of the engine body in plan view, the transmission shaft 93 is rotatably supported by support portions 94 fixed to the left and right engine body frames 21, and the transmission shaft 93 is disposed above the rear axle box 28 (between the left and right engine body frames 21 and the rear axle box 28 in side view). A transmission shaft 95 is connected to the transmission shaft 93 via a universal joint 82, and the transmission shaft 95 is connected to the rice transplanting device 5. Thus, as shown in fig. 5, 7, and 8, the power of the drive shaft 60 is transmitted to the seedling planting device 5 via the inter-plant speed changing device 85, the bevel gears 87 and 88, the seedling planting clutch 92, the output shaft 86, and the drive shafts 93 and 95.

[ Power Transmission Structure for Transmission to output section ]

As shown in fig. 3, 5, and 10, a transmission gear 96 is fixed to a portion of the travel output shaft 78 protruding from the transmission case 17, and a portion of the travel output shaft 78 located between the universal joint 82 and the transmission case 17 is fitted with a transmission case 97 (corresponding to a transmission mechanism) so as to cover the transmission gear 96 and to be relatively rotatably fitted over the travel output shaft 78 and the transmission gear 96 via a bearing 98, and the transmission case 97 is connected to the transmission case 17 so that the travel output shaft 78 and the transmission gear 96 cannot be rotated together.

As shown in fig. 3, 5, and 10, the output shaft 99 is provided on the transmission case 97 and projects rearward, and the output shaft 99 is located at a lower portion of the rear portion of the transmission case 17 (a position slightly on the right side of the left-right center CL of the machine body in plan view). In the transmission case 97, a transmission gear 100 is externally fitted to an output shaft 99 so as to be relatively rotatable, transmission gears 96 and 100 are meshed with each other, a displacement member 101 is externally fitted to the output shaft 99 so as to be integrally rotatable and slidable by a spline structure, and a spring 102 is provided for biasing the displacement member 101 to the side meshed with the transmission gear 100. Thus, a clutch 103 is formed inside the transmission case 97 to transmit and block the power of the travel output shaft 78 to and from the output shaft 99.

As shown in fig. 3, an operation arm 104 for operating the clutch 103 in the blocking state (for operating the displacement member 101 to be separated from the transmission gear 100) is provided on the right side portion of the transmission case 97, an opening portion 20a is formed in the reinforcing member 20, and the operation arm 104 faces the opening portion 20a of the reinforcing member 20. As shown in fig. 3 and 8, the operating lever 91 that operates the seedling planting clutch 92 in the blocking state (performs an operation of separating the shift member 89 from the bevel gear 87) protrudes rightward from the transmission case 17, similarly to the operating arm 104.

According to the above configuration, the travel output shaft 78 is fixed to the transmission case 17 and projects therefrom, and the drive shaft 99 is connected to the projecting end portion thereof via the universal joint 82, whereby the power of the travel output shaft 78 is transmitted to the rear axle case 28. Further, power for driving the output unit 13 is output via the transmission gear 96 on the travel output shaft 78 and the transmission gear 100 on the output shaft 99 in the transmission case 97. A clutch 103 for transmitting and blocking power is provided in the vicinity of the travel output shaft 78 in the transmission mechanism. The operation arm 104 is interlocked with the operation of blocking the rice transplanting clutch 92, and the clutch 103 biased to the transmission side by the spring 102 is blocked.

As shown in fig. 3 to 5, a transmission shaft 105 (corresponding to a transmission mechanism) is connected to the output shaft 99, extends rearward, is disposed at a position slightly to the right of the left and right center CL of the machine body in plan view, rotatably supports the transmission shaft 105 on a support portion 106 fixed to the left and right machine body frames 21, and is disposed above the rear axle box 28 (the transmission shaft 105 is disposed so as to pass between the left and right machine body frames 21 and the rear axle box 28 in side view). An operation arm 105a is fixed to the transmission shaft 105, and a link 107 (corresponding to a transmission mechanism) is connected between the input portion 13a of the output portion 13 located above and the operation arm 105a of the transmission shaft 105. Accordingly, the power of the travel output shaft 78 is transmitted to the propeller shaft 105 via the transmission case 97 (the transmission gears 96 and 100, the clutch 103, and the output shaft 99), and the rotational power of the propeller shaft 105 is transmitted to the input portion 13a of the output portion 13 via the connecting rod 107 as the power for pushing and pulling.

[ constitution of transplanting device ]

Next, the structure of the rice transplanting device 5 will be described in detail with reference to fig. 11 to 13.

The rice transplanter body 111 of the rice transplanter device 5 is composed of a main frame 114 formed of a horizontal square tubular material, a feed box 115 supported at the horizontal center of the main frame 114, and the above-mentioned transmission case 6 extending rearward from a plurality of horizontal portions of the main frame 114. On both lateral sides of the rear end portion of each transmission case 6, seedling transplanting mechanisms 113 are provided. A seedling placing table 10, in which a plurality of seedling placing parts 10a for respectively supplying seedlings to the plurality of transplanting mechanisms 113 are arranged in parallel in the lateral direction, is provided above and in front of each transplanting mechanism 113. The seedling placing table 10 is set in an assembly posture that is slightly inclined rearward toward the lower end side. A guide rail 118 for the seedling placing table 10 is provided on the lower end side of the seedling placing table 10. The ground float 9 is connected to the lower side of the rice transplanter body 111 so as to be vertically swingable around a horizontal axis at the rear end thereof.

As shown in fig. 12 and the like, each seedling transplanting mechanism 113 includes: the seedling box 7 is rotatably supported by the transmission box 6 via a horizontal drive shaft 113a, seedling arms 8 pivotally supported at both ends of the seedling box 7 about axes parallel to the drive shaft 113a, seedling claws 113d integrally rotatably supported by the respective seedling arms 8, a seedling pushing member 113e supported by the respective seedling arms 8 in a sliding-driving manner, and the like.

The driving force input from the drive shaft 95 to the feed box 115 is transmitted to the drive shaft 113a via a drive mechanism and a transmission mechanism (not shown) using gears or chains, which are located inside the feed box 115 and the transmission box 6, and the seedling box 7 is rotated. When the seedling box 7 rotates, the seedling arms 8 rotate together around the axis of the drive shaft 113a, and the seedling arms 8 rotate on their own axes relative to the seedling box 7 by a gear-type drive mechanism (not shown) located inside the seedling box 7. Thus, in each of the seedling planting mechanisms 113, the pair of seedling planting claws 113d reciprocate in different phases. That is, the front end of each of the seedling-transplanting claws 113d reciprocates in the vertical direction along the rotation locus T shown in fig. 13, and performs the following seedling-transplanting movement: when the front end of one seedling-transplanting claw 113d is located at the upper end of the rotation locus T, the front end of the other seedling-transplanting claw 113d is located at the lower end of the rotation locus T.

[ mounting Structure of seedling stage ]

As shown in fig. 13, the mounting portion of the seedling placing table 10 is formed by a horizontal upper rail 131, and the upper rail 131 is fixed to the back surface of a portion which is separated upward by a length D from the center of gravity G of the seedling placing table 10. As shown in fig. 12, the seedling placing table frame 119 is provided with: a pair of right and left support columns 119a and a support column connecting rod 119b fixed to the main frame 114 of the rice transplanter body 111. The mounting portion of the seedling placing table 10 is supported by the upper end portions of the two support columns 119a of the seedling placing table frame 119 via a coupling mechanism. The connection mechanism is provided with: a suspension coupling mechanism 130A, an elevation adjustment mechanism 130B, and a rotation coupling portion 130C.

As shown in fig. 15 to 16 and 18, the suspension coupling mechanism 130A includes: the upper rail 131, support rollers 133 fitted into guide grooves 132 of the upper rail 131 at a plurality of positions in the lateral direction, support arms 135 supporting the support rollers 133 at the distal end side via roller support shafts 134, a link lever 135a pivotally supporting and connecting the roller support shafts 134, support shafts 136 parallel to the roller support shafts 134, and support levers 137 pivotally supporting and connecting the base end sides of the support arms 135 to the intermediate portions via the support shafts 136. The connecting leg portions 137a at both ends of the support rod 137 are connected to the support end portion 119c of the support column 119 a.

As shown in fig. 18, the upper rail 131 is engaged with and fitted over each support roller 133. That is, the upper rail 131 is guided by the support rollers 133 by the rotation of the support rollers 133, and moves in either the left or right direction with respect to the roller support shaft 134 in the lateral direction.

As shown in fig. 18, the support peripheral surface of the support roller 133 is provided with a parallel engagement surface 133a, a front-side inclined engagement surface 133b, and a rear-side inclined engagement surface 133. The parallel engagement surface 133a is formed in parallel with the rotation axis 134a at an intermediate portion in the direction of the rotation axis 134a of the support roller. The front inclined engaging surface 133b is formed on the front side of the parallel engaging surface 133a so as to be inclined with respect to the rotation axis 134a so as to approach the rotation axis 134a toward the front side. The rear inclined engaging surface 133c is formed on the rear side of the parallel engaging surface 133a so as to be inclined with respect to the rotation axis 134a so as to approach the rotation axis 134a toward the rear side. Parallel engaging surfaces 132a, front inclined engaging surfaces 132b, and rear inclined engaging surfaces 132c corresponding to the parallel engaging surfaces 133a, the front inclined engaging surfaces 133b, and the rear inclined engaging surfaces 133c of the support roller 133 are provided on the upper guide surface and the lower guide surface of the upper rail 131. In this way, the support roller 133 and the upper rail 131 are engaged with the engaging surfaces 133a, 132a parallel to the rotation axis 134a and the engaging surfaces 133b, 132b, 133c, 132c inclined to the rotation axis 134 a.

Thus, in the suspension coupling mechanism 130A, the support rollers 133 are supported by the seedling placing table frame 119 via the support arms 135 and the support rods 137. Further, each support roller 133 is supported by the upper rail 131, so that the seedling placing table 10 is suspended and supported at a position above the center of gravity G thereof, and is capable of reciprocating in the lateral direction with respect to the seedling placing table frame 119. Since the suspension coupling mechanism 130A is disposed above, the reciprocating movement can be performed more smoothly than in a configuration in which the suspension coupling mechanism is coupled and supported on the lower side so that a large half of the load acts on the lower end side. In addition, although muddy water is likely to adhere to the lower side of the seedling placing table 10 during work, the generation of friction due to muddy water can be suppressed by such an upper arrangement.

As shown in fig. 12 and 16 to 18, the elevation adjustment mechanism 130B includes: the upper guide rail 131, the support arms 135, the interlocking lever 135a, an adjustment lever 138 integrally rotatably connected to a support shaft 136 extending in the front-rear direction of one (here, the lateral center) support arm 135, and a lever guide member 139 supported by the adjustment lever 138 supported by the support lever 137. When the adjustment lever 138 is swung in the lateral direction around the fulcrum shaft 136 along the guide groove 139a, the fulcrum shaft 136 is rotated, and the support arm 135 is swung. Then, the other support arms 135 are also operated to swing by the interlocking action of the interlocking lever 135a, and all the support arms 135 are operated to move up and down the upper rail 131 in parallel with the support rod 137 via the support rollers 133. The adjustment lever 138 operated to the predetermined position is pivotally urged by a lock spring 138a (see fig. 15) coupled to the adjustment lever 138, and when the lever guide member 139 is engaged with the positioning recess 139b (see fig. 17), the adjustment lever 138 is held at the operation position by the lever guide member 139. Thereby, each support arm 135 is held at a swing position corresponding to the operation position of the adjustment lever 138 against the weight of the seedling placing table 10.

In this way, by holding the adjustment lever 138 at the operation position by the lever guide member 139, each support arm 135 swings up and down about the forward and backward support shaft 136, and acts on the upper rail 131 via the support roller 133. Thus, the lifting operation force or the holding force acts on a portion above the center of gravity position G of the seedling placing table 10, and the seedling placing table 10 is lifted and held at the lifting position with respect to the seedling placing table frame 119.

As shown in fig. 12, 15, and the like, the pivotal connection portion 130C is configured by connecting the connection leg portions 137a of the support rod 137 so as to be pivotable with respect to the support end portion 119C of the support column 119a via left and right connection pins 137 b. The upper rail 131 is provided as a mounting portion above the center of gravity G of the seedling placing table 10. The upper rail 131 is coupled to the seedling placing table frame 119 so as to be rotatable about a lateral axis P passing through each coupling pin 137B and rotatable together with the suspension coupling mechanism 130A and the elevation adjustment mechanism 130B.

Locking mechanisms 142 are detachably provided on the right and left sides of the seedling table frame 119, and each locking mechanism 142 is constituted by a locking bolt fitted between a bolt hole 140 provided in the support end portion 119c of the support column 119a and a bolt hole 141 provided in the coupling leg portion 137a of the support rod 137. By the action of the locking mechanism 142, the seedling table 10 is locked to the seedling table frame 119 so as not to be rotatable.

As shown in fig. 13 and 19, a guided portion 10b to which a guided member is attached is provided on the back surface of the lower end portion of the seedling placing table 10. The guide rail 118 is formed with a guide groove 118a into which the guided portion 10b is inserted. Thus, the guide rail 118 is supported by the transmission case 6 of the rice transplanter body 111 via the left and right support mechanisms 150 provided at both lateral ends.

The support mechanism 150 includes: a support member 151 fixed to the transmission case 6, and a mounting rod 153 whose upper end is fixed to the guide rail 118 by a coupling bolt 152.

The lower end of the mounting rod 153 is inserted into a guide hole of a pair of upper and lower guide portions 154 of the support member 151, and is slidably locked to the support member 151. Thereby, the guide rail 118 and the rice transplanter body 111 are engaged together in such a manner as not to be relatively movable in the lateral direction. Thus, even if the seedling placing table 10 is conveyed in the lateral direction, the guide rail 118 is not moved therewith but supported on the seedling planting machine body 111. The guided portion 10b is provided with a resin shoe 10 c. The resin shoe 10c is guided by the two guide surfaces 118b in the guide groove 118a, and the seedling placing table 10 is moved and guided in the lateral direction by the guide rail 118 at the lower end portion thereof.

The guide rail 118 and the rice transplanter body 111 are engaged with each other so as to be movable in the vertical direction by engagement of the support members 151 and the mounting rods 153 in the left and right support mechanisms 150. In addition, since the guided portion 10b of the seedling placing table 10 is inserted into the guide groove 118a of the guide rail 118, the guide rail 118 and the seedling placing table 10 are engaged with each other so as to be movable integrally in the vertical direction. Thus, when the seedling placing table 10 is moved in the up-down direction by the elevation adjustment mechanism 130B, the guide rail 118 is moved in the up-down direction together with the seedling placing table 10 with respect to the seedling planting machine body 111.

As shown in fig. 19(a) and 19(b), the guide groove 118a of the guide rail 118 opens upward and rearward. When the seedling placing table 10 swings up and down with respect to the seedling planting machine body 111 about the lateral axis P of the aforementioned rotating and coupling part 130C, the lower end part of the seedling placing table 10 is switched between the ascending open management state shown in fig. 19(b) and the descending closed working state shown in fig. 19 (a). In the raised open management state, the guided portion 10b of the seedling placing table 10 is separated upward from the guide groove 118a, and is thereby separated from the guide rail 118. In this state, as shown in fig. 14, the lower end of the seedling placing table 10 is raised and moved away from the rotation locus T of the transplanting mechanism 113. On the other hand, in the lowered and closed operation state, the guided portion 10b of the seedling placing table 10 enters the guide groove 118a from above and engages with the guide rail 118. In this state, as shown in fig. 13, the lower end portion of the seedling placing table 10 interferes with the rotation locus T of the transplanting mechanism 113 in a side view.

As shown in fig. 14 and 19, a locking lever 160 for the seedling placing table and a rod-shaped support member 161 are provided at both ends of the seedling placing table in the lateral direction on the back side of the lower end portion of the seedling placing table 10.

Each locking lever 160 is rotatably supported on the frame portion of the seedling table 10 around the axial center of the coupling bolt 162, and when being rotationally operated, is switched between a locked state in which the distal end side of the locking lever 160 is inserted below the end portion 118c of the guide rail 118 to fix the lower end side of the seedling table 10 in the lowered closed operation state (see fig. 19(a)) and an unlocked state in which the distal end side of the locking lever 160 is released from the lower side of the end portion 118c of the guide rail 118 to release the fixation in the lowered closed operation state (see fig. 19 (b)).

Each support member 161 is connected to a frame portion of the seedling placing table 10 at a connection portion located at one end of the support member 161 so as to be rotatable about a lateral axis of the connection portion, and is configured to be capable of swinging up and down with respect to the seedling placing table 10. By the swing up-and-down operation, each support member 161 is switched between a use state (see fig. 14) in which it hangs down from the seedling placing table 10 and its free end portion enters the guide groove 118a of the guide rail 118 and is locked, and a storage state (see fig. 13) in which it is locked to the holder of the seedling placing table 10 in a vertical posture at the back side of the seedling placing table 10. The support member 161 switched to the use state has a cantilever supporting function with respect to the seedling placing table 10 by using the guide rail 118 as a reaction member, and holds the lower end portion of the seedling placing table 10 in the above-described lifted open management state against gravity. The supporting member 161 switched to the storage state releases the cantilever support with respect to the seedling placing table 10, so that the lower end portion of the seedling placing table can be lowered to the lowered closing operation state.

As shown in fig. 19 to 21, a member having an L-shaped cross section is integrally formed on the lower side of the guide rail 118 to constitute a seedling stopper 165, and a cutout is formed in the seedling stopper 165, and a seedling extraction opening 166 corresponding to each transplanting mechanism 113 is formed through the cutout.

The stopper 165 serves as a stopper for the clustered seedlings placed on the seedling placing parts 10a of the seedling placing table 10. Specifically, the stopper 165 fixedly holds the lower end of the tufted seedling in a state of extending a predetermined length from the lower end of the seedling placement unit 10a to the rotation locus T of the transplanting mechanism 113. The seedling take-out ports 166 are arranged so that the front end sides of the seedling-transplanting claws 113d of the seedling-transplanting mechanism 113 that performs seedling transplanting movement take out a group of seedlings from the lower end portions of the clustered seedlings through the seedling take-out ports 166. A seedling guide member 167 is provided to extend downward from each of the seedling outlet openings 166 in the stopper 165.

As shown in fig. 12 to 13, a transverse feeding mechanism 170 is provided between the feeding box 115 and the seedling placing table 10, and the transverse feeding mechanism 170 includes a transverse feeding shaft 171 extending laterally from the feeding box 115 to one side, a transverse feeding arm 172 extending from the back side of the seedling placing table 10, and the like.

The traverse feeder 173 attached to the traverse shaft 171 is coupled to the traverse arm 172 so as to be movable integrally therewith. The traverse feed shaft 171 is rotated in conjunction with the driving of the transplanting mechanism 113 by a driving mechanism (not shown) in the feed box 115. The traverse feed body 173 engages with a spiral groove (not shown) provided on the outer peripheral surface of the traverse shaft 171, and the traverse shaft 171 reciprocates along the spiral groove by a predetermined stroke to move the traverse arm 172. The traverse mechanism 170 reciprocates the transplanting movements of the respective transplanting mechanisms 113 in the transverse direction in conjunction with each other.

A coupling pin hole 174 (refer to fig. 5) provided in the traverse feeding arm 172 for coupling the traverse feeder 173 is formed as a long hole to achieve an interlocking engagement for allowing the seedling placing table 10 to be operated to be lifted by the lifting adjustment mechanism 130B.

As shown in fig. 12 to 14, a longitudinal feeding belt 180 is provided on the back surface of each seedling placing part 10a of the seedling placing table 10. A longitudinal feeding mechanism 185 is provided between the seedling placing table 10 and the feeding box 115, and the longitudinal feeding mechanism 185 comprises: a vertical feed arm 183 attached to a vertical feed shaft 182 that is interlocked with the drive wheel body 181 of each vertical feed belt 180, and a pair of right and left drive arms 184 provided to be drivable on the lateral outer sides of the feed box 115.

When the seedling placing table 10 is conveyed in the horizontal direction and reaches either of the left and right stroke end points, the vertical feed arm 183 abuts one of the drive arms 184 corresponding to the stroke end point, and is operated to swing by the drive arm 184 by a set stroke. Thereby, the longitudinal feed shaft 182 is driven by the set rotation angle, thereby driving each longitudinal feed belt 180 by the set stroke. Each time the seedling placing table 10 reaches the end points of the lateral feeding strokes, the longitudinal feeding mechanism 185 longitudinally feeds the tufted seedlings on the seedling placing portion 10a to the transplanting mechanism 113 by a set length on each longitudinal feeding belt 180. The vertical feed arm 183 is interlocked with the vertical feed shaft 182 via a one-way rotation clutch (not shown), and does not transmit power to the vertical feed shaft 182 when it is driven by the drive arm 184 and then returns to the standby position and swings.

That is, the pair of seedling raising claws 113d alternately pass through the seedling outlet 166 from above the lower end side of the seedling placing table 10 and pass through the inside of the seedling guide member 167 by each seedling raising mechanism 113, and are lowered onto the field surface. A sufficient seedling group is cut off from the lower end of the tufted seedlings placed on the seedling placing part 10a of the seedling placing table 10 at the seedling take-out port 166 by each seedling transplanting claw 113d, and taken out. The seedling is protected by the seedling guide member 167 to be lowered and conveyed so as not to fall off from the seedling planting claws 113d, and when lowered onto the soil of the field, the seedling is pushed into the soil from the seedling planting claws 113d by the seedling push-out member 113e, thus performing the seedling planting. This transplanting movement is alternately performed in the same row by a pair of transplanting claws 113 d.

In conjunction with the transplanting movement, the seedling placing table 10 is reciprocated in the lateral direction in a state where the upper end portion of the seedling placing table 10 is guided by the support roller 133 of the suspension coupling mechanism 130A and the lower end portion thereof is slidably guided by the guide rail 118 by the lateral feeding mechanism 170. At this time, the lower end portions of the tufted seedlings on the seedling placing part 10a are relatively moved in the lateral direction with respect to the seedling take-out port 166 along the seedling stopper 165 of the guide rail 118, whereby the seedling transplanting claws 113d of the respective seedling transplanting mechanisms 113 take out the seedling groups in order from one lateral end side to the other lateral end side of the lower end portions of the tufted seedlings. Thus, when the seedling placing table 10 is moved laterally, the seedling placing table 10 is moved laterally while being suspended and supported by the suspension coupling mechanism 130A, so that the load applied to the seedling placing table on the guide rail 118 becomes small.

The longitudinal feeding shaft 182 is driven by the longitudinal feeding mechanism 185 each time the seedling placing table 10 reaches the end of one of the lateral feeding strokes. Thereby, the longitudinal feeding belts 180 of the respective seedling placing parts 10a are rotated over a predetermined stroke, and the tufted seedlings of the respective seedling placing parts 10a are longitudinally fed to the seedling stopper parts 165 of the guide rails 118 by the longitudinal feeding belts 180. The longitudinal feeding amount corresponds to a length corresponding to the seedling take-out amount in the longitudinal direction by the transplanting mechanism 113.

When adjusting the seedling removal amount in the longitudinal direction of the seedling table obtained by the transplanting mechanism 113, the adjustment lever 138 is operated to swing along the guide groove 139a of the lever guide member 139, and the adjustment lever 138 positioned at the operation target position is engaged with and held by the positioning concave portion 139b of the lever guide member 139. Then, the support arms 135 of the elevation adjusting mechanism 130B perform an elevation action on the upper guide rails 131 of the seedling placing table 10, and perform an elevation adjustment of the seedling placing table 10 with respect to the seedling placing table frame 119. At this time, the mounting rods 153 of the left and right support mechanisms 150 of the guide rail 118 move up and down with respect to the support members 151 as the guide rail 118 moves, and the guide rail 118 moves up and down with respect to the seedling planting machine body 111 as the seedling placing table 10 moves. Then, the rotation locus T of the seedling stopper 165 of the guide rail 118 relative to the seedling raising mechanism 113 is raised and lowered, and the depth of the seedling raising claw 13d relative to the seedling removing port 166 changes when the seedling or the seedling raising claw 13d passes through the seedling removing port 166. Thereby, the size of the seedling group to be taken out by the transplanting mechanism 13 in the longitudinal direction of the placing table varies. That is, the seedling removal amount of each transplanting mechanism 113 is increased or decreased.

When the guided portion 10b of the seedling placing table 10 or the resin shoe 10C thereof is replaced and the maintenance work is performed on the guide rail 118 or the back surface side of the seedling placing table 10, the right and left lock levers 160 at the lower end portion are switched to the unlocking state, the rotation lock by the right and left lock mechanisms 142 of the rotation coupling portion 130C is unlocked, the coupling between the traverse arm 172 of the traverse feeding mechanism 170 and the traverse feeder 173 is released, and the lower end portion of the seedling placing table 10 is operated to be lifted and swung around the traverse axis P of the rotation coupling portion 130C, thereby being brought into the lifted and opened management state. Then, the guided portion 10b of the seedling placing table 10 is raised to be separated from the guide rail 118 and exposed, and the back surface side of the seedling placing table 10 and the part of the rice transplanting machine body normally covered with the seedling placing table 10 are opened. At this time, by using the support member 161, the lower end side is held in the lifted open management state without performing the supporting operation, and the work becomes easy. Therefore, when the desired replacement or maintenance of the seedling planting device 5 is performed, these operations can be performed easily as compared with a configuration that requires time and labor because the entire seedling placing table 10 needs to be removed. In addition, since the guided portion 10b and the resin shoe 10c thereof are opened from the guide rail 118 simultaneously with the ascending opening management state, replacement of these components can be performed quickly.

As shown in fig. 20 to 22, the seedling guide member 167 is composed of a pair of left and right side guide plates 168 and a center guide rod 169, upper end portions of the pair of side guide plates 168 are fixed to the seedling stopper 165 of the guide rail 118 by screw-fixing type mounting portions 168a, and upper end portions of the center guide rod 169 are coupled to upper end portions of the pair of left and right side guide plates 168.

The pair of left and right side guide plates 168 and the center guide bar 169 are formed by integral molding of a resin material, so that the seedling guide member 167 is integrally formed as an integral part.

The central guide bar 169 has an arch shape with a lateral width slightly smaller than the interval between the seedling planting claws 113d, and is disposed so that the depth of the central guide bar 169 entering the inside of the rotation locus T of the seedling planting claws 113d becomes deeper as the lower end side of the central guide bar 169 approaches, whereby the central guide bar 169 enters between the claws of the pair of right and left seedling planting claws 113d of the seedling planting arm 8, and can support the seedling held by the seedling planting arm 8. The upper end of the side guide plate 168 is provided with a connecting rod 168b which is positioned outside the seedling guide member with respect to the central guide rod 169 and connects the left and right side guide plates 168 to each other.

As shown in fig. 1 and 11, direction indicators 190 are provided on both lateral sides of the seedling placing table 10. As shown in fig. 23 to 25, the left and right direction indicators 190 are composed of a bulb housing recess 191, a light 192 disposed in the bulb housing recess 191, and a lens 193 covering the bulb housing recess 191 attached to the side wall 10e, and the bulb housing recess 191 is provided in the side wall 10e located at the most lateral end of the seedling table 10.

Positioning projections 192a are provided at two positions on the outer peripheral surface of the mounting shaft portion of the bulb 192. When the lighting unit 192 is assembled, the positioning protrusions 192a enter the upper side of the bulb support unit 194 from the notches 195 of the lighting support unit 194 of the lighting accommodation recess 191, and pass over the tapered protrusions 197 of the bulb support unit 194 while elastically deforming the seal member 196. One positioning projection 192a is a projection for abutting against the stopper projection 198 after passing over the tapered projection 197 to confirm that the bulb 192 has reached a predetermined mounting position, and on the other hand, the positioning projection 192a which has entered between the tapered projection 197 and the stopper projection 198 is a projection for abutting against the tapered projection 197 or the stopper projection 198 to prevent the bulb 192 from falling off.

As shown in fig. 26, a reinforcing bar 200 is provided on the back surface of the seedling placing table 10 along the widthwise direction of the seedling placing table 10. The reinforcing bar 200 includes a cable storage groove 201 as a wiring path formed along the reinforcing bar 200 and connecting piece portions 202 located on both lateral sides of the cable storage groove 201, and is connected to the seedling table 10 by the pair of connecting piece portions 202 in an assembly posture in which an opening of the cable storage groove 201 is closed by the seedling table 10. In addition, the electric cable 203 for the direction indicator 190 and the like is wired so as to be received in the cable receiving groove 201 at the back surface of the seedling placing table 10.

As shown in fig. 27, the main frame 114 of the rice transplanter body 111 is provided with a wire accommodating groove 206 formed on the lower surface side of the main frame 114 so as to open downward of the rice transplanter body, and a holder 209 detachably fixed to a locking portion 208 located on both sides in the lateral direction of the wire accommodating groove 206 to fix the wire 207 therein. The grippers 209 are disposed at a plurality of positions in the lateral direction of the main frame 114.

[ variation of embodiment 1 ]

(1) In the above embodiment, the output unit 13 is fixed to and supported by the body at the rear side of the driver seat 11, and the hopper 12 is provided above the output unit. Instead of this, it may be fixed in the following manner as shown in fig. 28: the support frame 108 is fixed to the rear axle box 28 so as to extend upward, and the output section 13 is fixed to the support frame 108 so as to be supported. And a hopper 12 is provided above the output portion 13. Here, the rear axle box 28 is provided with an output shaft 109 at the rear, and the power of the input shaft 38 is branched and transmitted to the output shaft 109. A connecting rod 110 is connected between the operating arm 109a of the output shaft 109 and the input portion 13a of the output portion 13.

Accordingly, the power of the travel output shaft 78 is transmitted to the output shaft 109 via the propeller shaft 84 and the input shaft 38, and the rotational power of the output shaft 109 is transmitted as the power to be pushed and pulled to the input portion 13a of the output portion 13 via the connecting rod 110.

(2) The suspension coupling mechanism 130A may be configured as shown in fig. 29. The suspension link mechanism 130A includes a support roller 133 and an upper rail 131, the support roller 133 having a circular arc-shaped support peripheral surface as an engagement surface 133d inclined with respect to a rotation axis 134a of the support roller 133, and the upper rail 131 having a circular arc-shaped upper guide surface and a circular arc-shaped lower guide surface as an engagement surface 132d inclined with respect to the rotation axis 134a of the support roller 133.

(3) The suspension coupling mechanism 130A may be configured as shown in fig. 30. Fig. 30 shows a suspension coupling mechanism 130A according to another embodiment. The suspension connection mechanism 130A includes a support roller 133 formed of a bearing member using a ball bearing.

(4) Although not shown, instead of the lifting/lowering mechanism 130B configured to swing the support arm 135 in the lateral direction about the front and rear axial cores to lift and lower the seedling placing table 10 as in the above-described embodiment, the lifting/lowering mechanism may be configured to swing the support arm in the front and rear direction about the lateral axial core to lift and lower the seedling placing table 10.

[ 2 nd embodiment ]

Next, embodiment 2 of the paddy field working vehicle according to the present invention will be described with reference to fig. 31 to 36. In the present embodiment, the description is also made based on a riding type rice transplanter.

The riding rice transplanter of the present embodiment has an overall configuration

In the riding rice transplanter shown in fig. 31, a hydraulic cylinder 4 for driving a link mechanism 3 and a link mechanism 4 to move up and down is provided at the rear part of a machine body provided with left and right front wheels 1 and left and right rear wheels 2, and a rice transplanting device (an example of a paddy field working device) 5 is supported at the rear part of the link mechanism 3.

As shown in fig. 31, the rice transplanting apparatus 5 is provided with: a transmission case 6, a transplanting box 7 rotatably supported at the rear part of the transmission case 6, a pair of transplanting arms 8 provided at both ends of the transplanting box 7, a ground float 9, a seedling placing table 10, and the like. Accordingly, as the seedling placing table 10 is driven to be fed horizontally and reciprocally, the seedling box 7 is driven to rotate, and the seedling arm 8 alternately takes out the seedling from the lower portion of the seedling placing table 10 and plants the seedling on the ground.

As shown in fig. 31 and 33, a transmission case 17 is disposed at the front of the machine body. An engine 19 is supported by a support arm 18 connected to a front portion of the transmission case 17. The right and left rectangular frame members 21 are connected to the upper part of the rear part of the transmission case 17 and extend rearward. A bottom plate 220 is provided above the transmission case 17 and the left and right body frames 21. A driver seat 11 is provided at an upper portion of the rear portion of the floor panel 220. In the front of the floor 220, an engine 19 and a hood 244 covering the engine 19 are provided. A control panel 27 is provided on the upper portion of the hood 244.

As shown in fig. 31, left and right pedal bases 236 connected to the base 220 are provided laterally outward of the hood 244 on the left and right sides. Left and right preliminary seedling placing tables 237 are provided laterally outward of the left and right step bottom plates 236, and 3 preliminary seedling placing portions 237a are supported on the preliminary seedling placing tables 237 in the vertical direction.

The fertilizer application device of the riding type rice transplanter is configured as shown in fig. 31. That is, in this fertilizer application device, an output portion 13 that outputs fertilizer (an example of a stored material) from a hopper 12 that stores the fertilizer is fixed to and supported by the body on the rear side of a driver seat 11 provided on a bottom plate 220 of the body. A hopper 12 is provided above the output portion 13. A blower 14 is provided below the driver seat 11. The ground float 9 is provided with a furrow opener 15 (corresponding to a supply portion), and a hose 16 is connected between the output portion 13 and the furrow opener 15. Thus, as the seedlings are planted, a predetermined amount of fertilizer is discharged from the hopper 12 through the discharging unit 13 at a time, the fertilizer is supplied to the furrow opener 15 through the hose 16 by the wind from the blower 14, and the fertilizer is supplied to the ground through the furrow opener 15.

Direct seeding may be performed by storing seeds in the hopper 12 instead of fertilizer, and supplying the seeds from the hopper 12 to the bottom surface via the furrow opener 15 (in this case, the seedling planting device 5 is stopped).

[ front wheel support Structure and Transmission Structure ]

As shown in fig. 33 and 34, the left and right front axle boxes 23 extend from the left and right lateral side surfaces of the transmission case 17, and cylindrical support portions 23a directed diagonally downward and forward (see the vertical axis P1) are provided at the end portions of the left and right front axle boxes 23. The front wheel support portions 24 that support the left and right front wheels 1 are supported by the support portions 23a of the left and right front axle boxes 23 so as to be rotatable about the vertical axis P1 and slidable in the direction of the vertical axis P1. As shown in fig. 32 and 33, the steering arm 25 is supported at a lower portion of the transmission case 17 so as to be swingable about a vertical axis P8 and extends rearward, and a tie rod 26 is connected between the front wheel support portion 24 and the steering arm 25. As a result, the steering arm 25 is swung by the steering wheel 27, and the left and right front wheels 1 are steered.

As shown in fig. 33 and 34, a hydrostatic continuously variable transmission 33 is coupled to a left lateral side portion of the transmission 17, and power of the engine 19 is transmitted to the hydrostatic continuously variable transmission 33 via a transmission belt 35. The power of the hydrostatic continuously variable transmission 33 is transmitted to a propeller shaft 63 incorporated in the right and left front axle boxes 23 via a sub-transmission (not shown) incorporated in the transmission case 17 (capable of shifting gears in two stages, i.e., high and low), and a differential transmission mechanism (not shown).

As shown in fig. 34, a bevel gear 68 (upper side) and a support member 69 (lower side) are supported by the support portions 23a of the left and right front axle boxes 23 via bearings 67, and a bevel gear 66 fixed to the propeller shaft 63 meshes with the bevel gear 68. The transmission shaft 70 is integrally rotatably and slidably fitted with a bevel gear 68 and a support member 69 via a spline structure, and a bevel gear 71 is fixed to a lower end of the transmission shaft 70.

As shown in fig. 34, the front wheel support portion 24 includes a front axle 72 for supporting each front wheel 1, a bevel gear 73 fixed to the front axle 72, and a cylindrical sleeve 74 fixed to an upper end of the front wheel support portion 24. The front wheel support 24 and the sleeve 74 are rotatably supported by the propeller shaft 70 via bearings 75, and a seal member 76 is provided between the support 23a of the left and right front axle boxes 23 and the sleeve 74, and the bevel gears 71 and 73 are meshed with each other. The support member 77 is in contact with the upper bearing 75, and the suspension spring 40, which is composed of a coil spring, is provided between the support member 69 and the support member 77.

Thus, as shown in fig. 33 and 34, the power of the hydrostatic continuously variable transmission 33 is transmitted from the propeller shaft 63 to the left and right front wheels 1 via the propeller shaft 70 and the front axle 72. The front wheel support 24 is supported by the support 23a of the left and right front axle boxes 23 so as to be rotatable about the longitudinal axis P1 and slidable in the direction of the longitudinal axis P1, and the suspension spring 40 acts by sliding in the direction of the longitudinal axis P1 with respect to the front wheel support 24.

As described above, the suspension mechanism 260 for the left and right front wheels 1 is constituted by the support portions 23a of the left and right front axle boxes 23, the front wheel support portions 24, the suspension springs 40, and the like.

[ supporting structure and Transmission structure of rear wheel ]

As shown in fig. 33, 35, and 36, the rear axle box 28 is formed by providing a laterally long center portion 28a and left and right lateral portions 28b extending diagonally rearward and downward from the center portion 28a, and the left and right rear wheels 2 are supported on the left and right lateral portions 28b of the rear axle box 28. The vertically long left and right brackets 22 having a cross section of コ are fixed to the front portion of the central portion 28a of the rear axle box 28, and the left and right upper links 29 are supported so as to be vertically swingable about a horizontal axis P2 at the upper portions of the left and right brackets 22 and extend forward, and are supported so as to be vertically swingable about a horizontal axis P3 at the intermediate portion of the left and right body frames 21.

As shown in fig. 33, 35, and 36, a support pin 31 is fixed to the inner side of the left and right lateral portions 28b of the rear axle box 28 coaxially with the rear axle 43 supporting the left and right rear wheels 2, and a bracket 262 is fixed between the end of the support pin 31 and the left and right lateral portions 28b of the rear axle box 28. The left and right lower links 30 are supported to be vertically swingable about a horizontal axis P4 of the support pin 31 and extend forward, and are supported to be vertically swingable about a horizontal axis P5 of a lower portion of the rear portion of the transmission case 17.

As shown in fig. 35 and 36, the suspension frame 261 is formed by bending an elongated plate material into a vertically long コ shape, the bracket 261a fixed to the lower portion of the suspension frame 261 is supported so as to be swingable around the lateral axis P4 of the support pin 31, and the suspension frame 261 extends laterally outward of the left and right lower links 3a of the link mechanism 3, inward of the left and right lateral side portions 28b of the rear axle box 28, and upward rearward of the central portion 28a of the rear axle box 28. Support pins 221a are fixed to the rear portions of the left and right body frames 21, the support pins 221a of the left and right body frames 21 are inserted into long holes 261b formed in the upper portions of the suspension frames 261, and two anti-slip pins 263 are attached to the support pins 221a of the left and right body frames 21.

As shown in fig. 35 and 36, a support member 264 is slidably fitted around an upper portion of the suspension frame 261, and the suspension spring 32 formed of a coil spring is fitted around the suspension frame 261 so as to be positioned between the bracket 261a of the suspension frame 261 and the support member 264. The rubber member 265 is attached so as to be positioned below the elongated hole 261b of the suspension frame 261, the rubber member 266 is attached to the upper portion of the suspension frame 261, and the support members 264 are pressed against the support pins 221a of the left and right body frames 21 by the biasing force of the suspension springs 32. As shown in fig. 33, 35, and 36, the cross bar 34 is supported so as to be vertically swingable about a front-rear axis P6 of a bracket 221c fixed to the left body frame 21, and is supported so as to be vertically swingable about a front-rear axis P7 of the central portion 28a of the rear axle box 28.

As described above, the suspension mechanism (an example of the rear wheel suspension mechanism) 267 of the right and left rear wheels 2 is constituted by the suspension frame 261, the suspension springs 32, and the like. As a result, as shown in fig. 31, 35, and 36, the rear axle box 28 is supported by the right and left suspension springs 32 so as to be vertically movable and rotatable, the position of the rear axle box 28 in the front-rear direction is determined by the right and left upper links 29 and the right and left lower links 30, and the position of the rear axle box 28 in the left-right direction is determined by the lateral link 34.

[ supporting states of front and rear wheels ]

The states shown in fig. 33, 35 and 36 show the transplanting operation state (for example, a state of about 40% of the full-load state of the seedling placing table 10, the preliminary seedling placing table 237 and the hopper 12). In the transplanting operation state, as shown in fig. 35 and 36, the support pins 221a of the left and right support frames 21 are positioned at the center of the elongated hole 261b of the suspension frame 261 (the center position of the operation stroke of the suspension spring 32), and as shown in fig. 34, the front wheel support 24 is positioned at the center of the operation stroke on the support portions 23a of the left and right front axle boxes 23. Thus, in the transplanting operation state, the state shown in fig. 31 is achieved, that is, the bottom plate 220 and the left and right pedal bottom plates 236 are substantially horizontal.

With respect to the aforementioned transplanting operation state, i.e. in other words

LA＝FA/RA≈FB/RB＝LB

Wherein,

LA: displacement of the suspension spring 40

LB: displacement of suspension spring 32

FA: load acting on right (left) front wheel 1

FB: load acting on right (left) rear wheel 2

RA: spring constant of two-layer suspension spring 40

RB: spring constant of suspension spring 32

Thus, the floor 220 and the left and right step floors 236 are substantially horizontal in a state where the left and right front wheels 1 and the left and right rear wheels 2 are in contact with a horizontal paved road.

Next, in the fully loaded state of the seedling placing table 10, the preliminary seedling placing table 237 and the hopper 12, the support pins 221a of the left and right support frames 21 shown in fig. 35 and 36 are positioned at the lower ends of the elongated holes 261b of the suspension frame 261, and the left and right rear wheels 2 (rear axle boxes 28) are in a state in which they can be lowered with respect to the machine body but cannot be raised above the machine body. Similarly, the front wheel receiving portion 24 (sleeve 74) shown in fig. 34 abuts on the bearing 67 or the support member 69, and the left and right front wheels 1 are in a state in which they can be lowered with respect to the engine body (receiving portions 23a of the left and right front axle boxes 23) but cannot be raised with respect to the engine body (receiving portions 23a of the left and right front axle boxes 23) to a level higher than the engine body.

In the unloaded state of the seedling placing table 10, the preliminary seedling placing table 237 and the hopper 12, the support pins 221a of the left and right support frames 21 shown in fig. 35 and 36 are positioned at the upper ends of the elongated holes 261b of the suspension frame 261, and the left and right rear wheels 2 (rear axle boxes 28) are in a state in which they can be raised with respect to the machine body but cannot be lowered below the machine body. Similarly, the stopper ring 70a at the upper end of the transmission shaft 70 shown in fig. 34 abuts on the bevel gear 68, and the left and right front wheels 1 are raised with respect to the machine body (the support portions 23a of the left and right front axle boxes 23) but are not lowered with respect to the machine body (the support portions 23a of the left and right front axle boxes 23) to a level below the machine body.

[ Power Transmission Structure for transmitting to rear wheel ]

As shown in fig. 32 and 33, the travel output shaft 78 is provided at the rear of the transmission case 17 and projects rearward, the input shaft 38 projects forward to the front of the central portion 28a of the rear axle case 28, and the travel output shaft 78 and the input shaft 38 are connected together via a universal joint 82, a cylindrical expansion joint 83, and a propeller shaft 84.

As shown in fig. 32, the rear axle box 28 is provided with a propeller shaft 39, and a bevel gear 38a fixed to the input shaft 38 meshes with a bevel gear 39a fixed to the propeller shaft 39. Left and right side clutches 41 of a friction multi-plate type are provided at left and right end portions of the propeller shaft 39, and propeller shafts 42 are provided between the left and right side clutches 41 and rear axles 43 of the left and right rear wheels 2. As a result, as shown in fig. 32 and 33, the power of the hydrostatic continuously variable transmission 33 is transmitted to the right and left rear wheels 2 via the travel output shaft 78, the propeller shaft 84, the input shaft 38, the propeller shaft 39, the right and left side clutches 41, and the propeller shaft 42.

As shown in fig. 32, the left and right side clutches 41 are biased to a transmission state by springs (not shown), left and right operation arms 51 are provided for operating the left and right side clutches 41 in a blocking state, and a connecting rod 53 is connected between the steering arm 25 and the left and right operation arms 51. The state shown in fig. 32 is a state in which the right and left front wheels 1 are steered to the straight-ahead position a0 and the right and left side clutches 41 are operated to the power transmitting state, and power is transmitted to the right and left front wheels 1 and the right and left rear wheels 2. Even if the left and right front wheels 1 are steered between the straight-ahead position a0 and the left-right set angle a1, the body is linearly advanced or gently steered to the right or left while maintaining the above state.

As shown in fig. 32, when the left and right front wheels 1 are steered between the right set angle a1 and the right operation limit a2, the right connecting rod 53 is pulled by the steering arm 25, the right side clutch 41 is operated to the disengaged state by the right operation arm 51, and the right rear wheel 2 is set to the free rotation state. In this case, the left side brake 41 is kept in the power transmission state, and the power is still transmitted to the left rear wheel 2. When the left and right front wheels 1 are steered between the left set angle a1 and the left operation limit a2, the left connecting rod 53 is pulled by the steering arm 25, the left side clutch 41 is operated to the disengaged state by the left operation arm 51, and the left and right rear wheels 2 are in the free rotation state. In this case, the right side brake 41 is kept in a power transmission state, and power is still transmitted to the right rear wheel 2.

In this way, when the left and right front wheels 1 are steered between the right set angle a1 and the right steering limit a2 or between the left set angle a1 and the left steering limit a2, the following states are achieved: the power is transmitted to the right and left front wheels 1 and the rear wheels 2 on the turning outer side, and the power transmitted to the rear wheels 2 on the turning center side is blocked, so that the rear wheels 2 on the rotation center side are in a freely rotatable state, thereby performing a right turn or a left turn. Thus, the rear wheel 2 on the turning center side is in a state of advancing while being appropriately rotated along with turning, and the problem of ground damage caused by the rear wheel 2 on the turning center side during turning is reduced.

[ variation of embodiment 2 ]

Instead of the above configuration, the suspension mechanism 267 according to embodiment 2 may be configured as in the following modifications (1) to (3).

(1) As shown in fig. 37, a rod-shaped suspension frame 272 is provided, a bracket 272a fixed to a lower portion of the suspension frame 272 is supported swingably around a horizontal axis P4 of a support pin 31, the suspension frame 272 is inserted slidably in the vertical direction into brackets 221b fixed to the left and right body frames 21, and a support member 272b is fixed to an upper end of the suspension frame 272.

As shown in fig. 37, a long 1 st coil spring 273 is externally fitted between the bracket 272a of the suspension frame 272 and the brackets 221b of the left and right body frames 21, and a short 2 nd coil spring 274 is externally fitted between the support member 272b of the suspension frame 272 and the brackets 221b of the left and right body frames 21. A1 st cylindrical member 275 (corresponding to a limiting mechanism) is fixed to the bracket 272a of the suspension frame 272, a1 st elastic member 277 (corresponding to a cushion mechanism) made of rubber or the like is fixed to the 1 st cylindrical member 275, a2 nd cylindrical member 276 (corresponding to a limiting mechanism) is fixed to the support member 272b of the suspension frame 272, and a2 nd elastic member 278 (corresponding to a cushion mechanism) made of rubber or the like is fixed to the 2 nd cylindrical member 276.

As described above, the suspension frame 272, the 1 st coil spring 273, the 2 nd coil spring 274, and the like constitute the suspension mechanism 267 of the right and left rear wheels 2.

The state shown in fig. 37 represents a transplanting work state (for example, a state of about 40% of a full load state of the seedling placing table 10, the preliminary seedling placing table 237 and the hopper 12). In the transplanting operation state, a distance L1 between the 1 st cylinder member 275 (the 1 st elastic member 277) and the brackets 221b of the left and right body frames 21 is larger than a distance L2 between the 2 nd cylinder member 276 (the 2 nd elastic member 278) and the brackets 221b of the left and right body frames 21 (a state in which an operation stroke of the suspension mechanism 267 toward a contraction limit in the transplanting operation state is larger than an operation stroke of the suspension mechanism 267 toward an extension limit in the transplanting operation state).

Thus, as shown in fig. 37, when the suspension mechanism 267 contracts from the transplanting operation state and reaches the contraction limit, the 1 st cylindrical member 275 (the 1 st elastic member 277) abuts against the brackets 221b of the left and right body frames 21. When the suspension mechanism 267 extends from the transplanting operation state to the extension limit, the 2 nd cylindrical member 276 (the 2 nd elastic member 278) abuts against the bracket 221b of the left and right body frames 21.

The structures and functions of the 1 st and 2 nd cylindrical members 275, 276 and the 1 st and 2 nd elastic members 277, 278 may be applied to the suspension mechanisms 260 of the left and right front wheels 1.

(2) In the example shown in fig. 38, instead of the 1 st and 2 nd cylindrical members 275, 276, the 1 st and 2 nd elastic members 277, 278 in the suspension mechanism 267 of [ modification 1 ] described above, the 1 st and 2 nd coil springs 273, 274 are formed as coil springs having different pitches, each of which includes a portion 273a, 274a having a larger pitch and a portion 273b, 274b having a smaller pitch.

The state shown in fig. 38 represents a transplanting work state (for example, a state of about 40% of a full load state of the seedling placing table 10, the preliminary seedling placing table 237 and the hopper 12). In the transplanting operation state, the length of the 1 st coil spring 273 is longer than the length of the 2 nd coil spring 274 (a state in which the operating stroke of the suspension mechanism 267 toward the contraction limit in the transplanting operation state is larger than the operating stroke of the suspension mechanism 267 toward the extension limit in the transplanting operation state).

Thus, as shown in fig. 38, when the suspension mechanism 267 contracts from the transplanting operation state and reaches the contraction limit, the portion 273a having a larger pitch and the portion 273b having a smaller pitch of the 1 st coil spring 273 contract similarly, and the pitch of the portion 273b having a smaller pitch of the 1 st coil spring 273 disappears, so that the portion 273b having a smaller pitch of the 1 st coil spring 273 loses its function as a coil spring, and the suspension mechanism 267 reaches the contraction limit. In this case, since the portion 273a of the 1 st coil spring 273 having the larger pitch still continues to function as a coil spring without losing its pitch, the portion 273a of the 1 st coil spring 273 having the larger pitch functions as a buffer mechanism for absorbing the shock when the suspension mechanism 267 reaches the contraction limit.

As shown in fig. 38, in the case where the suspension mechanism 267 extends from the state of the rice transplanting work and reaches the extension limit, the portion 274a of the 2 nd coil spring 274 having the larger pitch and the portion 274b having the smaller pitch contract similarly, while the pitch of the portion 274b of the 2 nd coil spring 274 having the smaller pitch disappears, so that the portion 274b of the 2 nd coil spring 274 having the smaller pitch loses its function as a coil spring, and the suspension mechanism 267 is in the state of reaching the extension limit. In this case, since the portion 274a of the 2 nd coil spring 274 having a large pitch has not yet disappeared to continue to function as a coil spring, the portion 274a of the 2 nd coil spring 274 having a large pitch functions as a shock absorbing mechanism for absorbing shock when the suspension mechanism 267 reaches the extension limit.

The structure and function of the 1 st coil spring 273 and the 2 nd coil spring 274 as described above can be applied to the suspension mechanism 260 of the left and right front wheels 1.

(3) Fig. 39 shows another modification of embodiment 2.

In the configuration of fig. 39, the operating arms 3b (corresponding to the telescopic drive mechanism) are fixed to the base portions of the left and right lower links 3a of the link mechanism 3, and the left and right operating arms 3b of the link mechanism 3 are spaced upward from the upper portion of the suspension frame 261 in a state where the seedling planting device 5 is positioned on the ground. Accordingly, in a state where the seedling planting device 5 is driven to ascend and descend by the hydraulic cylinder 4 within a predetermined height from the ground, the left and right operation arms 3b of the link mechanism 3 do not abut on the upper portion of the suspension frame 261.

When the rice transplanting apparatus 5 is driven to rise above a predetermined height from the ground by the hydraulic cylinder 4, the left and right operating arms 3b of the link mechanism 3 come into contact with the upper portion of the suspension frame 261, whereby the suspension frame 261 is pushed down, and the left and right rear wheels 2 (rear axle boxes 28) are driven to fall (the suspension mechanism 267 is forcibly operated to extend). In this case, when the rice transplanting device 5 is driven to the upper limit position by the hydraulic cylinder 4, the support pins 221a of the left and right support frames 21 reach the upper ends of the elongated holes 261b of the suspension frames, and the suspension mechanism 267 reaches the extension limit.

The structure and function of the left and right operating arms 3b of the link mechanism 3 as described above can also be applied to the suspension mechanism 267 of modification 1 or modification 2.

[ ALL PROBLEMS ] to solve the problems

Finally, the characteristic configuration of the transmission mechanisms 97, 105, and 107 for driving the output unit 13 described in embodiment 1 can be applied to the configuration of embodiment 2 and its modifications.

Claims (8)

1. A paddy field working vehicle in which rear axle boxes (28) supporting left and right rear wheels are supported on a machine body via suspension mechanisms, a transmission case (17) for transmitting power from an engine (19) to the left and right rear wheels (2) is fixed to the machine body, and an output part (13) for supplying stored materials in a hopper (12) to the ground is supported on the machine body,

a traveling output shaft (78) of the transmission case protrudes from the transmission case, and a transmission shaft (84) is connected to the protruding end portion thereof via a universal joint (82), whereby power of the traveling output shaft is transmitted to the rear axle box via the universal joint (82) and the transmission shaft (84),

the power is output from the travel output shaft to one end of a transmission mechanism (97, 105, 107) for driving the output unit, and the other end of the transmission mechanism is connected to the output unit.

2. The paddy field work vehicle according to claim 1, wherein a clutch (103) for transmitting and blocking power is provided at a portion of the transmission mechanism located in the vicinity of the travel output shaft.

3. The paddy field work vehicle according to claim 1, wherein the transmission mechanism is disposed between a support member (21) that supports the body of the rear axle box and the rear axle box.

4. The paddy field work vehicle according to claim 1, wherein the transmission mechanism is supported by a support member (21) of a body supporting the rear axle box.

5. The paddy field work vehicle as set forth in claim 1, wherein the suspension mechanism (260, 267) is provided on the front wheels and the rear wheels.

6. The paddy field work vehicle as claimed in claim 1, wherein a limiting mechanism is provided for determining the extension limit and the contraction limit of the suspension mechanism, and the operation stroke (L1) of the suspension mechanism toward the contraction limit is made larger than the operation stroke (L2) toward the extension limit by the limiting mechanism.

7. The paddy field work vehicle as claimed in claim 6, wherein a damper mechanism is provided for absorbing an impact when the suspension mechanism reaches the extension limit and the contraction limit.

8. The paddy field work vehicle as claimed in claim 1, wherein the suspension mechanism (267) is provided on each of the rear wheels, and the paddy field work device (5) is connected to a rear part of the body in a manner liftable from the ground via a lifting mechanism (4),

a forced extension mechanism (3b) for forcibly extending the suspension mechanism when the paddy field working device is raised to a height exceeding a predetermined height.

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