JP2006347188A - Hst unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an HST unit to serve for a hydraulic pump device and a hydraulic motor device constituting a continuously variable speed change mechanism on the running system, capable of making efficient their operations of piping and connecting, adjusting, and mounting on a vehicle body. <P>SOLUTION: The HST unit is equipped with the first hydraulic motor device 200a to drive actively one of a pair of drive wheels, the second hydraulic motor device 200b to drive actively the other drive wheel, the hydraulic pump device to be coupled with and actuated by a drive source and constituting the continuously variable speed change mechanism of the running system in cooperation with the first 200a and second hydraulic motor devices 200b, and a mounting frame capable of being mounted on the vehicle frame and supporting the first and second hydraulic motor devices and the hydraulic pump device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an HST unit having a pair of hydraulic motor devices that can be independently arranged and a hydraulic pump device that cooperates with the pair of hydraulic motor devices to form a traveling system continuously variable transmission mechanism.

It has been conventionally known that a traveling system continuously variable transmission mechanism is configured by fluidly connecting a separately disposed hydraulic pump device and a hydraulic motor device via a pipe.
Such a configuration is particularly useful in a working vehicle that requires a space between a pair of drive wheels to stabilize the vehicle body posture during turning, such as a riding mower tractor capable of turning in an interlining (zero turn). (See Patent Document 1).

  However, in the conventional configuration, the hydraulic pump device and the hydraulic motor device are independently attached to the vehicle main unit at the time of assembling work to the vehicle main unit, and thereafter, the hydraulic pump device and the hydraulic motor device are There is a problem in that the assembly workability is poor because the gaps must be connected by piping.

Further, it is preferable that the adjustment operation of the traveling system continuously variable transmission mechanism formed by the hydraulic pump device and the hydraulic motor device is performed by fluidly connecting the hydraulic pump device and the hydraulic motor device in a state that matches the use conditions. However, the conventional configuration has a problem that the adjustment work can be performed only after the hydraulic pump device and the hydraulic motor device are attached to the vehicle main unit.
U.S. Pat.No. 6,425,244

  The present invention has been made in view of the above-described prior art, and improves the efficiency of piping connection work, adjustment work, and attachment work to the vehicle body of the hydraulic pump device and the hydraulic motor device constituting the traveling system continuously variable transmission mechanism. An object is to provide an HST unit that can be realized.

  In order to achieve the above object, the present invention provides a first hydraulic motor device that operatively drives one of a pair of drive wheels, a second hydraulic motor device that operatively drives the other of a pair of drive wheels, and a drive A hydraulic pump device operatively connected to a power source, wherein the hydraulic pump device forms a traveling system continuously variable transmission mechanism in cooperation with the first and second hydraulic motor devices; the first hydraulic motor device; There is provided an HST unit comprising a two-hydraulic motor device and an attachment frame for supporting the hydraulic pump device, the attachment frame being attachable to a vehicle frame.

In one aspect, the hydraulic pump device includes an input shaft operatively connected to a drive source, first and second hydraulic pump bodies operatively driven by power from the input shaft, and the first and second 2. A pump case for housing a hydraulic pump body, wherein one end is fluidly connected to the first hydraulic pump body and the other end is opened on the outer surface, and the first hydraulic pump side hydraulic fluid path and one end are And a pump case including a second hydraulic pump side hydraulic fluid passage that is fluidly connected to the second hydraulic pump main body and has the other end opened to the outer surface.
The first hydraulic motor device houses a first motor shaft that operatively drives the one drive wheel, a first hydraulic motor body that rotationally drives the first motor shaft, and the first hydraulic motor body. A first motor case including a first hydraulic motor side hydraulic fluid passage having one end fluidly connected to the first hydraulic motor main body and the other end opened to the outer surface.
The second hydraulic motor device houses a second motor shaft that operatively drives the other drive wheel, a second hydraulic motor body that rotationally drives the second motor shaft, and the second hydraulic motor body. A second motor case including a second hydraulic motor side hydraulic fluid passage having one end fluidly connected to the second hydraulic motor main body and the other end opened to the outer surface.
In such an aspect, the HST unit includes a first hydraulic fluid pipe that fluidly connects the first hydraulic pump side hydraulic fluid passage and the first hydraulic motor side hydraulic fluid passage, the second hydraulic pump side hydraulic fluid passage, A second hydraulic oil pipe for fluidly connecting the second hydraulic motor side hydraulic oil path;
The first and second hydraulic oil pipes may be supported by the mounting frame.

In another aspect, the hydraulic pump device may include first and second hydraulic pump devices that can be arranged independently of each other.
Each of the first and second pump devices includes an input shaft that is operatively connected to the drive source, a hydraulic pump body that is operatively driven by power from the input shaft, and a pump that houses the hydraulic pump body And a pump case including a hydraulic pump side hydraulic fluid passage having one end fluidly connected to the hydraulic pump main body and the other end opened to the outer surface.
The first hydraulic motor device houses a first motor shaft that operatively drives the one drive wheel, a first hydraulic motor body that rotationally drives the first motor shaft, and the first hydraulic motor body. A first motor case including a first hydraulic motor side hydraulic fluid passage having one end fluidly connected to the first hydraulic motor main body and the other end opened to the outer surface.
The second hydraulic motor device houses a second motor shaft that operatively drives the other drive wheel, a second hydraulic motor body that rotationally drives the second motor shaft, and the second hydraulic motor body. A second motor case including a second hydraulic motor side hydraulic fluid passage having one end fluidly connected to the second hydraulic motor main body and the other end opened to the outer surface.
In such an aspect, the HST unit includes a first hydraulic fluid pipe that fluidly connects the hydraulic pump side hydraulic fluid passage and the first hydraulic motor side hydraulic fluid passage in the first pump device, and the second pump device. And a second hydraulic oil pipe that fluidly connects the hydraulic pump side hydraulic oil path and the second hydraulic motor side hydraulic oil path.
The first and second hydraulic oil pipes may be supported by the mounting frame.

In still another aspect, the hydraulic pump device includes an input shaft that is operatively connected to a drive source, a traveling hydraulic pump body that is operatively driven by power from the input shaft, and the traveling hydraulic pump body. A pump case including a hydraulic pump side hydraulic fluid passage having one end fluidly connected to the traveling hydraulic pump main body and the other end opened to the outer surface.
The first hydraulic motor device houses a first motor shaft that operatively drives the one drive wheel, a first hydraulic motor body that rotationally drives the first motor shaft, and the first hydraulic motor body. A first motor case including a first hydraulic motor side hydraulic fluid passage having one end fluidly connected to the first hydraulic motor main body and the other end opened to the outer surface.
The second hydraulic motor device houses a second motor shaft that operatively drives the other drive wheel, a second hydraulic motor body that rotationally drives the second motor shaft, and the second hydraulic motor body. A second motor case including a second hydraulic motor side hydraulic fluid passage having one end fluidly connected to the second hydraulic motor main body and the other end opened to the outer surface.
In such an aspect, the HST unit includes a motor-side piping that fluidly connects the first and second hydraulic motor-side hydraulic fluid passages, and a hydraulic oil piping that fluidly connects the hydraulic pump-side hydraulic fluid passage and the motor-side piping. With.
The motor side piping and the hydraulic oil piping may be supported by the mounting frame.
Preferably, the hydraulic pump device may further include another hydraulic pump body housed in the pump case so as to be operatively driven by power from the input shaft.

  In the various aspects, preferably, the mounting frame is mounted on the vehicle frame, and the first and second motor support surfaces located on one side and the other side in the vehicle width direction, and the first and second A front view portal shape is provided that includes a pump support surface positioned above the motor support surface and positioned between the first and second motor support surfaces in the vehicle width direction.

In one example, the pump support surface may extend horizontally such that a rotation axis of the hydraulic pump body is along a vertical direction in a state where the mounting frame is mounted on a vehicle frame.
In another example, the pump support surface may extend vertically so that a rotation axis of the hydraulic pump body is along a horizontal direction in a state where the mounting frame is mounted on a vehicle frame.
In this other example, preferably, the mounting frame is a support surface that integrally extends downward from the pump support surface, and supports a PTO clutch device inserted in a PTO transmission path from the drive source to the work implement. It may have a supporting surface.

  In the various aspects, preferably, the hydraulic pump device may further include a PTO shaft that outputs rotational power from the input shaft to the outside.

According to the HST unit of the present invention, the hydraulic pump device, the first hydraulic motor device and the second hydraulic motor device constituting the traveling system continuously variable transmission mechanism are previously supported by the mounting frame, and then the mounting frame is mounted on the vehicle. By attaching it to the frame, the operation of attaching the traveling system continuously variable transmission mechanism to the vehicle main body can be completed.
Therefore, it is possible to improve the efficiency of the work of attaching the hydraulic pump device, the first hydraulic motor device, and the second hydraulic motor device to the vehicle main unit.

Also, the pipe connection work between the hydraulic pump device and the first and second hydraulic motor devices can be performed before these hydraulic devices are attached to the vehicle main unit.
Accordingly, the efficiency of the pipe connection work can be improved, and the adjustment work of the traveling system continuously variable transmission mechanism can be improved regardless of the vehicle main unit.
Such an effect is that a hydraulic device manufacturer manufactures the hydraulic pump device, the first hydraulic motor device, and the second hydraulic motor device, and the vehicle main unit manufacturer mounts these hydraulic devices on a vehicle frame to install a working vehicle. This is particularly effective when completed.

  Furthermore, since the hydraulic pump device, the first hydraulic motor device, and the second hydraulic motor device are independently supported by the mounting frame, maintenance or replacement of these hydraulic devices can be easily performed.

Embodiment 1
A preferred first embodiment of an HST unit according to the present invention will be described below with reference to the accompanying drawings.
1 and 2 are a side view and a partial rear view of a working vehicle 1A to which the HST unit 100A according to the present embodiment is applied.

  As shown in FIGS. 1 and 2, the working vehicle 1A includes a vehicle frame 30, a drive source 40A supported by the vehicle frame 30, the HST unit 100A that constitutes a traveling system continuously variable transmission mechanism, A traveling system power transmission mechanism 10A that transmits power from the drive source 40A to the HST unit 100A, a pair of first drive wheels 50a and second drive wheels 50b (rear wheels in the present embodiment), and caster wheels 60 ( In this embodiment, a front wheel) is provided.

In the present embodiment, the working vehicle 1A is a rear discharge type passenger mower.
That is, the work vehicle 1A further includes a driver's seat 35, a work machine 70 (in this embodiment, a mower device) supported to be lifted and lowered between the drive wheel 50 and the caster wheel 60. The PTO system power transmission mechanism 20A that transmits power from the drive source 40A to the work implement 70 and the grass cut by the work implement 70 are guided to a grass collection bag (not shown) disposed at the rear of the vehicle body. And a duct 80 for the purpose.

The HST unit 100A is configured such that a traveling system continuously variable transmission mechanism can be formed while securing a free space between the pair of drive wheels 50a and 50b.
Specifically, as shown in FIGS. 1 and 2, the HST unit 100A operates the first hydraulic motor device 200a that operatively drives the first drive wheel 50a and the second drive wheel 50b. And a hydraulic pump device 300A operatively connected to the drive source 40A and fluidly connected to the first and second hydraulic motor devices 200a and 200b. The hydraulic pump device 300A, the first hydraulic motor device 200a, and the second hydraulic motor device 200b are supported so that a free space is defined between 300A and the first and second drive wheels 50a, 50b. And an attachment frame 500A.

At least one of the hydraulic pump device 300A and the first and second hydraulic motor devices 200a and 200b is a variable displacement type.
In the present embodiment, the hydraulic pump device 300A is a variable displacement type, and the first and second hydraulic motor devices 200a and 200b are fixed displacement types.

FIG. 3 shows a longitudinal rear view of the vicinity of the first hydraulic motor device 200a.
The second hydraulic motor device 200b has substantially the same configuration as the first hydraulic motor device 200a.
Accordingly, the second hydraulic motor device 200b is denoted by the same reference numeral as that of the first hydraulic motor device 200a or the same reference numeral changed to “b”, and detailed description thereof is omitted.

As shown in FIG. 3, the first hydraulic motor device 200a is configured to operatively drive the corresponding first drive wheel 50a.
Specifically, the first hydraulic motor device 200a houses a first hydraulic motor main body 210a, a first motor shaft 220a that is driven to rotate about an axis by the first hydraulic motor main body 210a, and the first hydraulic motor main body 210a. And a first motor case 230a that supports the first motor shaft 220a so as to be rotatable about its axis.

  The first motor case 230a has an opening through which the first hydraulic motor main body 210a can be inserted on one end surface (in the present embodiment, the end surface facing inward in the vehicle width direction when installed on the vehicle frame 30). The motor case main body 240a is provided, and a first motor side port block 250a (first motor side center section) connected to the motor case main body 240a so as to close the opening.

The first motor side port block 250a is provided with a pair of first hydraulic motor side hydraulic fluid passages 255a having one end fluidly connected to the first hydraulic motor main body 210a and the other end opened to the outer surface. ing.
The other end of the pair of first hydraulic motor side hydraulic fluid passages 255a forms a first hydraulic motor hydraulic fluid port 255a (P) that serves as a fluid connection port with a first hydraulic pump body 310a described later. Yes.

One end of the first motor shaft 220a is operatively connected to the drive axle 51 of the first drive wheel 50a.
Preferably, as shown in FIG. 3, the first motor shaft 220 a can be operatively connected to the corresponding drive axle 51 via the speed reduction transmission mechanism 55.
By providing such a speed reduction transmission mechanism 55, the capacity of the first hydraulic motor main body 210a can be reduced.
In the present embodiment, a planetary gear mechanism is used as the speed reduction transmission mechanism 55, and the corresponding motor shaft and axle are concentrically arranged. It is also possible to offset the corresponding motor shaft and axle using one or a plurality of gear trains provided on two shafts arranged in parallel.
Furthermore, the speed reduction transmission mechanism 55 can be omitted by increasing the volume of the first hydraulic motor main body 210a.

In the present embodiment, the first hydraulic motor device 200a includes a brake mechanism 270 that can selectively apply a braking force to the first motor shaft 220a in addition to the above configuration.
Specifically, the other end of the first motor shaft 220a (the end opposite to the end that is operatively connected to the first drive wheel 50a) extends outward from the first motor-side port block 250a. Be present.
The brake mechanism 270 is configured to selectively apply a braking force to the other end of the first motor shaft 220a based on an external operation.

In the present embodiment, the brake mechanism 270 is an inward expansion type.
Specifically, a brake drum 271 supported on the other end of the first motor shaft 220a so as not to rotate relative thereto, a brake shoe 272 disposed opposite to an inner peripheral surface of the brake drum 271, and the brake shoe 272 Urging member 273 that urges the brake shoe 271 in a direction away from the inner peripheral surface of the brake drum 271, and presses the brake shoe 272 against the inner peripheral surface of the brake drum 271 against the urging force of the urging member 273. And a brake operation arm 274 to be operated.
In the present embodiment, the inward expansion type brake device is employed as the brake mechanism 270 as described above, but other brake devices such as a disk type brake device may be used as a matter of course.

FIG. 4 shows a longitudinal rear view of the vicinity of the hydraulic pump device 300A.
As shown in FIG. 4, in the present embodiment, the hydraulic pump device 300A is a first hydraulic fluid that is fluidly connected to the first hydraulic motor main body 210a and the second hydraulic motor main body (not shown). A pump main body 310a and a second hydraulic pump main body 310b are provided, and the first and second hydraulic pump main bodies 310a and 310b are accommodated in a single pump case 330A.

  Specifically, the hydraulic pump device 300A includes an input shaft 370 operatively connected to the drive source 40A, first and second pump shafts 320a and 320b, and the input shaft 370 to the first and second pumps. A transmission mechanism 380 for transmitting power to the shafts 320a and 320b, first and second hydraulic pump bodies 310a and 310b supported on the first and second pump shafts 320a and 320b so as not to rotate relative to each other, A pump case 330A is provided that accommodates the second hydraulic pump bodies 310a and 310b and supports the input shaft 370 and the first and second pump shafts 320a and 320b so as to be rotatable about the axis.

As described above, in the present embodiment, the hydraulic pump device 300A is a variable displacement type.
Therefore, in addition to the above-described configuration, the hydraulic pump device includes first and second volume adjustment mechanisms for changing the supply and discharge amounts of the first and second hydraulic pump bodies 310a and 310b, respectively, based on an external operation. 450a and 450b are provided.
The first and second volume adjustment mechanisms 450a and 450b are respectively based on an output adjustment member 460 (see FIG. 4) such as a movable swash plate that changes the amount of oil supplied to and discharged from the corresponding hydraulic pump main body 310 and an external operation. A control shaft 470 (see FIG. 1) for tilting the output adjusting member 460 is provided.
The control shafts 470 of the first and second volume adjusting mechanisms 450a and 450b are respectively connected to a pair of control levers 36a and 36b disposed in front of the driver's seat 35 via appropriate link mechanisms 37a and 37b. Are operatively connected (see FIG. 1).

  The pump case 330A is detachably connected to the pump case body 340A, a pump side port block 350A (pump side center section) detachably connected to the pump case body 340A, and the pump case body 340A. 360A.

As shown in FIG. 4, the pump case body 340A includes an end wall 341A extending in a direction substantially orthogonal to the axial direction of the pump shafts 320a and 320b, and a peripheral portion of the end wall 341A. And a peripheral wall 342A extending in the axial direction.
The peripheral wall 342A is open on the free end side opposite to the end wall 341A.
The opening is sized such that the first and second hydraulic pump bodies 310a and 310b can be inserted therethrough.

The pump side port block 350A is connected to the pump case body 340A so as to close the opening.
That is, a pump housing space for housing the first and second hydraulic pump bodies 310a and 310b is defined by the end wall 341A and the peripheral wall 342A of the pump case body 340A and the pump-side port block 350A. It has become.

The pump-side port block 350A has a pair of first hydraulic pump-side hydraulic fluid passages 355a having one end fluidly connected to the first hydraulic pump main body 310a and the other end opened to the outer surface, and one end portion A pair of second hydraulic pump-side hydraulic fluid passages 355b that are fluidly connected to the second hydraulic pump main body 310b and that have the other end opened on the outer surface are provided.
The other end of the pair of first hydraulic pump side hydraulic fluid passages 355a forms a first hydraulic pump hydraulic fluid port 355a (P) that serves as a fluid connection port with the first hydraulic motor main body 210a. (See FIG. 2).
The other end of the pair of second hydraulic pump side hydraulic fluid passages 355b forms a second hydraulic pump hydraulic fluid port 355b (P) that serves as a fluid connection port with the second hydraulic motor main body ( (See FIG. 2).

  The lid member 360A is coupled to the pump case main body 340A so as to define a transmission mechanism accommodating space for accommodating the transmission mechanism 380 between the lid member 360A and the end wall 341A.

  The input shaft 370 is supported by the pump case 330A in a state in which one end forming the input end is extended outward.

  The first and second pump shafts 320a and 320b are both supported by the lid member 360A and the pump-side port block 350A so that the corresponding hydraulic pump bodies 310a and 310b can be supported in the pump housing space. Has been.

The transmission mechanism 380 is configured to transmit power from the input shaft 370 to the first and second pump shafts 320a and 320b.
In the present embodiment, as shown in FIG. 4, the first pump shaft 320 a and the input shaft 370 are integrally formed by a single shaft 325.
Accordingly, the transmission mechanism 380 includes a driving gear 381 supported so as not to rotate relative to the single shaft 325 and a driven gear supported so as not to rotate relative to the second pump shaft 320b so as to mesh with the driving gear 381. 382.

Preferably, at least one end of one or both of the first and second pump shafts 320a and 320b protrudes outward from the pump case 330A.
Such a projecting end portion is used as a drive shaft of a charge pump main body or other rotating member attached to the hydraulic pump device 300A as desired.

In the present embodiment, as described above, the input shaft 370 and the first pump shaft 320a are integrally formed by the single shaft 325.
As shown in FIG. 4, the single shaft 325 protrudes outward through the lid member 360A so that one end portion forms the input end portion, and the other end portion is also the pump-side port block. It protrudes outward through 350A.
The other end portion of the single shaft 325 functions as a drive shaft of the charge pump main body 410 described later.
In the present embodiment, as shown in FIG. 4, the second pump shaft 320b also has the other end projecting outwardly through the pump-side port block 350A and rotating with respect to the outside. Power can be output.
For example, a cooling fan can be provided at the other end of the second pump shaft 320b.

In the present embodiment, the hydraulic pump device 300A includes a charge pump unit 400 in addition to the above configuration.
As shown in FIG. 4, the charge pump unit includes a charge pump main body 410 that is operatively driven by the rotational power of the input shaft 370, and a charge pump case 420 that surrounds the charge pump main body 410. .
In the present embodiment, the charge pump main body 410 is configured to be driven by the other end of the single shaft 325.
The charge pump case 420 is connected to the pump-side port block 350A so as to surround the charge pump main body 410.

  The mounting frame 500A supports the hydraulic pump device 300A, the first hydraulic motor device 200a, and the second hydraulic motor device 200b, and a free space is defined between the first and second drive wheels 50a and 50b. As described above, the vehicle frame 30 can be mounted.

  Specifically, as shown in FIG. 2, the mounting frame 500A is disposed on the one side in the vehicle width direction so as to be positioned in the vicinity of the first drive wheel 50a when mounted on the vehicle frame 30. 1 motor support surface 510a, a second motor support surface 510b disposed on the other side in the vehicle width direction so as to be positioned in the vicinity of the second drive wheel 50b, and the first and second motor support surfaces 510a and 510b. It is a front view portal shape provided with a pump support surface 520 positioned above and between the first and second motor support surfaces 510a and 510b in the vehicle width direction.

In the HST unit 100A provided with the mounting frame 500A, the mounting pump 500A, the first hydraulic motor device 200a, and the second hydraulic motor device 200b constituting the traveling continuously variable transmission mechanism are connected in advance to the mounting frame 500A. And then mounting the mounting frame 500A to the vehicle frame 30 so that a free space is secured between the first and second drive wheels 50a, 50b, and the hydraulic pump device 300A and the The work of attaching the first and second hydraulic motor devices 200a and 200b to the vehicle frame 30 can be completed.
Therefore, it is possible to improve the vehicle assembly work efficiency.

  Further, in the HST unit 100A, the hydraulic pump device 300A, the first hydraulic motor device 200a, and the second hydraulic motor device 200b are independently supported by the mounting frame 500A. Therefore, replacement of these hydraulic devices is possible. Work and maintenance work can be easily performed.

In the HST unit 100A, the pipe connection work between the first and second hydraulic pump bodies 310a and 310b and the first and second hydraulic motor bodies 210a and 210b is also performed by the hydraulic pump device 300A and the The first and second hydraulic motor devices 200a and 200b can be performed without being assembled to the vehicle frame 30.
That is, with the hydraulic pump device 300A and the first and second hydraulic motor devices 200a and 200b attached to the mounting frame 500A, the first hydraulic pump hydraulic oil port 355a (P) and the first hydraulic motor. Connecting the first hydraulic oil pump body 310a and the first hydraulic motor main body 210a by fluidly connecting the hydraulic oil ports 255a (P) with the first hydraulic oil pipe 480a; and The second hydraulic pump main body 310b is formed by fluidly connecting the second hydraulic pump hydraulic oil port 355b (P) and the second hydraulic motor hydraulic oil port 255b (P) through a second hydraulic oil pipe 480b. In addition, connection work between the second hydraulic motor main bodies can be performed.
In other words, the pipe connection work can be performed regardless of the work of assembling to the vehicle main unit.
Preferably, as shown in FIG. 2, the first hydraulic oil pipe 480a and the second hydraulic oil pipe 480b are supported by the mounting frame 500A.

Further, in the HST unit 100A, it is possible to improve the efficiency of the adjustment work of the traveling system continuously variable transmission mechanism constituted by the hydraulic pump device 300A and the first and second hydraulic motor devices 200a and 200b.
As described above, in the HST unit 100A, before the hydraulic pump device 300A, the first hydraulic motor device 200a, and the second hydraulic motor device 200b are attached to the vehicle frame 30, the first and second hydraulic pump bodies 310a, 310b. And the first hydraulic motor main body and the second hydraulic motor main body can be fluidly connected in a state in conformity with the use state.
Therefore, the adjustment work of the traveling system continuously variable transmission mechanism can be performed regardless of the vehicle main unit.
In particular, when the hydraulic equipment manufacturer manufactures the hydraulic pump device and the hydraulic motor device, and the vehicle manufacturer attaches the hydraulic pump device and the hydraulic motor device to the vehicle frame to complete the work vehicle, the traveling system is not included. Before the step transmission mechanism is shipped, the hydraulic device manufacturer can perform adjustment work of the hydraulic pump device and hydraulic motor device in accordance with the vehicle mounting state. The traveling system continuously variable transmission mechanism can be assembled with only a very simple operation of attaching to the vehicle.

Further, as described above, the mounting frame 500A is configured such that the first and second motor support surfaces 510a and 510b are positioned on one side and the other side in the vehicle width direction, respectively, when mounted on the vehicle frame 30. In addition, the gate shape is formed in a front view.
Therefore, only by attaching the mounting frame 500A to the vehicle frame 30, the pair of hydraulic motor devices 200a and 200b can be distributed and arranged in the vehicle width direction, and a free space can be secured between the drive wheels 50a and 50b.
Such an effect is particularly effective in, for example, a working vehicle that needs to stabilize the vehicle body posture during turning of the interlining (zero turn).
In the working vehicle, as shown in FIG. 2, the PTO power transmission mechanism 20A and the duct 80 are disposed in the free space.

  In the working vehicle 1A, as shown in FIGS. 1 and 2, the drive source 40A is of a vertical crankshaft type, and both the traveling system transmission mechanism 10A and the PTO system power transmission mechanism 20A are pulleys, It is a belt mechanism.

Specifically, the drive source 40A is supported by the vehicle frame 30 via a flat plate 45 installed on the rear side of the vehicle frame 30 so that the drive shaft 41 is along the vertical direction.
The flat plate 45 is provided with an opening through which the drive shaft 41 can be inserted.
The drive source 40A is placed on the upper surface of the flat plate 45 so that the shaft end of the drive shaft 41 is positioned below the flat plate 45 through the opening.
Preferably, the flat plate 45 is supported by the vehicle frame 30 via an elastic member 46, and thereby, it is possible to effectively prevent vibration from the drive source 40A from propagating to the vehicle frame 30.

The travel system power transmission mechanism 10A is mounted on the travel drive pulley 11 mounted on the drive shaft 41 of the drive source 40A and the input shaft 370 of the hydraulic pump device 300A so as to be positioned below the flat plate 45. The travel driven pulley 12 and the travel drive pulley 11 and the travel belt 13 wound around the travel driven pulley 12 are provided.
The PTO power transmission mechanism 20A is mounted on the work machine drive pulley 21 mounted on the drive shaft 41 of the drive source 40A so as to be positioned below the flat plate 45, and on the input shaft of the work machine 70. A work machine driven pulley 22 and a work machine drive pulley 21 and a work machine belt 23 wound around the work machine driven pulley 22 are provided.

  In order to simplify the connection structure between the vertical crankshaft type drive source 40A and the hydraulic pump device 300A, in this embodiment, the pump support surface 520 has the mounting frame 500A attached to the vehicle frame 30. In the mounted state, the hydraulic pump device 300A is supported so that the input shaft 370 is along the vertical direction.

Specifically, as shown in FIG. 2, the mounting frame 500 </ b> A is substantially on one side in the vehicle width direction so as to face the first drive wheel 50 a with reference to the state of being attached to the vehicle frame 30. A first side plate 550a that extends vertically, a second side plate 550b that extends substantially vertically on the other side in the vehicle width direction so as to face the second drive wheel 50b, and above the first and second side plates 550a and 550b and the vehicle A top plate 560 extending substantially horizontally at the center in the width direction, and a connecting plate 570 extending substantially vertically so as to connect the first and second side plates 550a, 550b and the top plate 560 are provided.
The top plate 560 constitutes the pump support surface 520, and the first and second side plates 550a and 550b constitute the first and second motor support surfaces 510a and 510b, respectively.
As shown in FIG. 2, the connecting plate 570 includes a first portion 570a extending upward from the first side plate 550a, a second portion 570b extending upward from the second side plate 550b, the first portion 570a, and the first portion 570a. The front portion has a connecting portion 570c that connects the upper portions of the second portions 570b, and thereby securing the free space between the first and second drive wheels 50a, 50b, The strength of the mounting frame 500A is ensured.

As shown in FIG. 2, the top plate 560 is provided with an opening, and the hydraulic pump device 300A is configured so that the input shaft 370 extends downward through the opening. It is supported on the top surface of.
The travel driven pulley 12 is attached to the input shaft 370 below the top plate 560.

Embodiment 2
Below, 2nd Embodiment of the HST unit which concerns on this invention is described, referring an accompanying drawing.
5 and 6 are a side view and a partial rear view of a working vehicle 1B to which the HST unit 100B according to the present embodiment is applied.
In the figure, the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The HST unit 100B according to the present embodiment is configured to be applied to a working vehicle 1B provided with a horizontal crankshaft type drive source 40B.

  Specifically, the working vehicle 1B includes the vehicle frame 30, a drive source 40B supported by the vehicle frame 30, the HST unit 100B according to the present embodiment, and the drive source 40B to the HST unit 100B. Travel system power transmission mechanism 10B for transmitting power to the first drive wheel 50a and the second drive wheel 50b, the caster wheel 60, the work implement 70, and the drive source 40B to the work implement 70. A PTO power transmission mechanism 20B for transmitting power and the duct 780 are provided.

The drive source 40B is supported by the vehicle frame 30 so that the drive shaft 41 extends forward in the horizontal direction.
Preferably, as shown in FIG. 5, the drive source 40B is supported by the vehicle frame 30 via four anti-vibration rubbers 47 arranged in the front, rear, left, and right directions. Vibration propagation to the vehicle frame 30 can be prevented as much as possible.

The HST unit 100B includes an attachment frame 500B in place of the attachment frame 500A in the HST unit 100A according to the first embodiment.
Specifically, the HST unit 100B is provided between the first hydraulic motor device 200a, the second hydraulic motor device 200b, the hydraulic pump device 300A, and the first and second drive wheels 50a and 50b. The hydraulic pump device 300A, the first hydraulic motor device 200a, and the mounting frame 500B that supports the second hydraulic motor device 200b are provided so as to define a free space.

The mounting frame 500 </ b> B supports the hydraulic pump device 300 </ b> A so that the input shaft 370 extends along the horizontal direction when mounted on the vehicle frame 30.
Specifically, as shown in FIG. 6, the mounting frame 500B includes the first side plate 550a that constitutes the first motor support surface 510a, the second side plate 550b that constitutes the second motor support surface 510b, A connecting plate 580B extending substantially vertically along the vehicle width direction so as to connect the first and second side plates 550a and 550b, and the connecting plate 580B constitutes the pump support surface 520. .
In the present embodiment, the hydraulic pump device 300A is supported on the front surface of the connecting plate 580B in a state where the input shaft 370 extends rearward through an opening formed in the connecting plate 580B. Yes.

The traveling transmission mechanism 10B is configured to operatively connect the drive shaft 41 of the drive source 40B and the input shaft 370 of the hydraulic pump device 300A.
In the present embodiment, the traveling transmission mechanism 10B is a universal joint 15 having one end connected to the drive shaft and the other end connected to the input shaft.

The PTO power transmission mechanism 20B is configured to transmit power from the other drive shaft 42 in the drive source 40B to the work implement 70.
That is, the PTO power transmission mechanism 20B is mounted on the work machine drive pulley 21 mounted on the other drive shaft 42 and the intermediate shaft 25 supported by the vehicle frame along the vehicle width direction. The direction change pulley 26, the work machine driven pulley 22 mounted on the input shaft of the work machine 70, the work machine drive pulley 21, the direction change pulley 26, and the work machine driven pulley 22 are wound around. And a working machine belt 23.

Preferably, the connecting plate 580B may have a frontal portal shape when the mounting frame 500B is attached to the vehicle frame 30, as shown in FIG. The free space between the two drive wheels 50a and 50b can be secured as much as possible.
In the present embodiment, the working machine belt 23 is disposed in the free space.

  Also in such HST unit 100B, the same effect as in the first embodiment can be obtained.

Embodiment 3
Below, 3rd Embodiment of the HST unit which concerns on this invention is described, referring an accompanying drawing.
7 and 8 are a side view and a partial rear view of a working vehicle 1C to which the HST unit 100C according to the present embodiment is applied.
In the figure, the same members as those in the first or second embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As in the second embodiment, the HST unit 100C according to the present embodiment is configured to be applied to a work vehicle 1C including a horizontal crankshaft type drive source 40B.

  Specifically, the working vehicle 1C includes the vehicle frame 30, a drive source 40B supported by the vehicle frame 30, the HST unit 100C according to the present embodiment, the traveling system power transmission mechanism 10B, The first drive wheel 50a and the second drive wheel 50b, the caster wheel 60, the work machine 70, a PTO system power transmission mechanism 20C that transmits power from the drive source 40B to the work machine 70, and And a duct 80.

  The PTO transmission mechanism 20C includes a work machine drive pulley 21 attached to the drive shaft 41, an intermediate shaft 27 disposed below the drive shaft 41 in parallel with the drive shaft 41, and the intermediate shaft. 27, the work machine intermediate pulley 28, the work machine drive pulley 21, the work machine belt 23 wound around the work machine intermediate pulley 28, and one end of the work machine 70 input shaft. A PTO clutch device 600 inserted between the transmission shaft 29 with a universal joint connected to the intermediate shaft 27 and the transmission shaft 29, and transmits power from the intermediate shaft 27 to the transmission shaft 29. And a PTO clutch device 600 that selectively engages / disengages.

The HST unit 100C includes an attachment frame 500C in place of the attachment frame 500B in the HST unit 100B according to the second embodiment.
Specifically, the HST unit 100C is provided between the first hydraulic motor device 200a, the second hydraulic motor device 200b, the hydraulic pump device 300A, and the first and second drive wheels 50a and 50b. The hydraulic pump device 300A, the first hydraulic motor device 200a, and the mounting frame 500C that supports the second hydraulic motor device 200b are provided so as to define a free space.

  The mounting frame 500C is inserted in a PTO transmission path from the drive source 40B to the work implement 70 in addition to the first and second hydraulic motor devices 200a and 200b and the hydraulic pump device 300A. The PTO clutch device 600 is configured to be supported.

That is, the mounting frame 500C is another support surface 530 that integrally extends downward from the pump support surface 520 when mounted on the vehicle frame 30, and is capable of supporting the PTO clutch device 600. A support surface 530 is provided.
Specifically, the mounting frame 500C includes the first side plate 550a constituting the first motor support surface 510a, the second side plate 550b constituting the second motor support surface 510b, and the first and second side plates. And a connecting plate 580C extending substantially vertically along the vehicle width direction so as to connect 550a and 550b.

In the connection plate 580C, the upper region forms the pump support surface 520, and the lower region forms the other support surface 530.
In the present embodiment, the hydraulic pump device 300A is supported on the front surface of the connecting plate 580C, and the PTO clutch device 600 is supported on the rear surface of the connecting plate 580C.

Further, as shown in FIG. 8, the connecting plate 580C has a frontal gate shape, thereby securing a free space between the first and second drive wheels 50a, 50b.
In the present embodiment, the duct 80 is disposed in the free space.

  Also in such HST unit 100C, the same effect as in the first and second embodiments can be obtained.

In each of the above embodiments, the hydraulic pump device in which both the first and second hydraulic pump bodies 310a and 310b are accommodated in the single pump case 330A has been described as an example. It is not limited to such a form.
That is, as the hydraulic pump device, a pair of first and second hydraulic pump devices supported by the mounting frame independently of each other can be provided.
In such an aspect, the first and second hydraulic pump devices are fluidly connected to the first and second hydraulic motor devices, respectively.

Embodiment 4
Hereinafter, a fourth embodiment of the HST unit according to the present invention will be described with reference to the accompanying drawings.
9 and 10 are a side view and a partial rear view of a working vehicle 1D to which the HST unit 100D according to the present embodiment is applied.
In the figure, the same members as those in the first to third embodiments are denoted by the same reference numerals, and the description thereof is omitted.

  The HST unit 100D according to the present embodiment constitutes a traveling system continuously variable transmission mechanism of the working vehicle 1D provided with a horizontal crankshaft type drive source 40B, and a PTO system transmission from the drive source 40B to the work implement 70. It also constitutes part of the path.

  Specifically, the working vehicle 1D includes the vehicle frame 30, a drive source 40B supported by the vehicle frame 30, the HST unit 100D according to the present embodiment, and the drive source 40B to the HST unit 100D. Travel system power transmission mechanism 10B for transmitting power to the first drive wheel 50a and the second drive wheel 50b, the caster wheel 60, the work implement 70, and the HST unit 100D to the work implement 70. A power transmission mechanism 20D for transmitting power and a duct 80 are provided.

  The HST unit 100D is a hydraulic pump device 300D that is operatively connected to the first hydraulic motor device 200a, the second hydraulic motor device 200b, and the drive source 40B, and includes the first and second hydraulic motor devices. A hydraulic pump device 300D that is fluidly connected to 200a and 200b and that can output rotational power toward the working machine 70, and the mounting frame 500B are provided.

FIG. 11 shows a longitudinal rear view of the hydraulic pump device 300D.
12 and 13 are sectional views taken along lines XII-XII and XIII-XIII in FIG. 11, respectively.

  As shown in FIGS. 11 to 13, the hydraulic pump device 300 </ b> D includes an input shaft 370 that is operatively connected to the drive source 40 </ b> B, the first and second pump shafts 320 a and 320 b, and the input shaft 370. A traveling transmission mechanism 380D for transmitting power to the first and second pump shafts 320a and 320b, and the first and second hydraulic pump bodies supported by the first and second pump shafts 320a and 320b so as not to rotate relative to each other. 310a, 310b, a PTO shaft 700 that outputs rotational power to the outside, a PTO transmission mechanism 710 that transmits power from the input shaft 370 to the PTO shaft 700, and the first and second hydraulic pump bodies 310a. , 310b and the input shaft 370, the first pump shaft 320a, the second pump shaft 320b, and the PTO shaft 700 as axes. And a pump case 330D rotatably supporting Ri.

As in the first embodiment, also in the present embodiment, the hydraulic pump device 300D is a variable displacement type.
Therefore, the hydraulic pump device 300D includes the first and second volume adjusting mechanisms 450a and 450b in addition to the above-described configuration.
As shown in FIG. 12, the first and second volume adjusting mechanisms 450a and 450b are configured based on an output adjusting member 460 such as a movable swash plate for changing the supply / discharge oil amount of the corresponding hydraulic pump main body and an external operation. And a control shaft 470 for tilting the output adjustment member 460.

  As shown in FIGS. 12 and 13, the pump case 330D includes a pump case body 340D, first and second pump side port blocks 350Da and 350Db that are detachably connected to the pump case body 340D, and the pump. A lid member 360D removably coupled to the case main body 340D.

The pump case body 340D includes a first end wall 341D extending in a direction perpendicular to the axis of the pump shafts 320a and 320b, and a second end wall 340D spaced apart from the first end wall 341D in the axial direction of the pump shafts 320a and 320b. A second end wall 343D that is an end wall 343D extending in a direction orthogonal to the axis of the pump shafts 320a and 320b, and a peripheral wall 342D that connects the peripheral edges of the first end wall 341D and the second end wall 343D. And have.
The second end wall 343D is provided with first and second openings into which the first and second hydraulic pump bodies 310a and 310b can be inserted, respectively.
On the peripheral wall 342D, the control shafts 470 of the first and second volume adjusting mechanisms 450a and 450b are supported so as to be rotatable around the axis line in a state where they can be externally operated.

The first and second pump-side port blocks 350Da and 350Db are detachably connected to the pump case body 340D so as to close the first and second openings, respectively.
A pair of first hydraulic pump side hydraulic fluid passages 355a are formed in the first pump side port block 350Da.
Similarly, a pair of second hydraulic pump side hydraulic fluid passages 355b are formed in the second pump side port block 350Db.
In the present embodiment, as described above, the pair of first and second pump side port blocks 350Da and 350Db are provided, but it is of course possible to provide a single pump side port block. .

  The lid member 360D is connected to the pump case main body 340D so as to define a transmission mechanism accommodation space for accommodating the transmission mechanism 380D between the lid member 360D and the first end wall 341D.

The input shaft 370 is supported by the pump case 330D in a state in which one end forming an input end is extended outward.
In the present embodiment, the input shaft 370 is supported by the lid member 360D and the second end wall 343D, and one end portion constituting the input end portion extends outward from the lid member 360D. Be present.

  The first and second pump shafts 320a and 320b may support the corresponding hydraulic pump main bodies 310a and 310b in the pump housing space, and the lid member 360D, the first end wall 341D, and the corresponding It is supported by pump side port blocks 350Da and 350Db.

The travel transmission mechanism 380D is configured to transmit power from the input shaft 370 to the first and second pump shafts 320a and 320b in the pump case 330D.
In the present embodiment, the traveling transmission mechanism 380D includes a drive gear 381D that is supported by the input shaft 370 so as not to rotate relative to the input shaft 370, and the first and second pump shafts so as to mesh with the drive gear 381D. 320a and 320b have first and second driven gears 382Da and 382Db supported so as not to rotate relative to each other.

In the present embodiment, the PTO shaft 700 includes a first PTO shaft 701 that outputs rotational power forward from the pump case 330D and a second PTO shaft that outputs rotational power backward from the pump case 330D. 702.
The first PTO shaft 701 is operatively connected to the input shaft of the work implement 70 via the PTO power transmission mechanism 20D (the transmission shaft 29 with a universal joint in the present embodiment).
The second PTO shaft 702 is operatively connected to another working machine (not shown) disposed behind the vehicle frame via an appropriate transmission mechanism.

The PTO transmission mechanism 710 is configured to transmit power from the input shaft 370 to the first and second PTO shafts 701 and 702 in the pump case 330D.
In the present embodiment, the PTO transmission mechanism 710 is configured to selectively engage or block power transmission from the input shaft 370 to the first and second PTO shafts 701 and 702. .

Specifically, the PTO transmission mechanism 710 includes a PTO hydraulic clutch device 720 as shown in FIGS.
The PTO hydraulic clutch device 720 includes a drive side member 721 operatively connected to the input shaft 370 and a driven side member 722 operatively connected to the first and second PTO shafts 701 and 702. By the action, the power transmission from the driving side member 721 to the driven side member 722 can be engaged or interrupted.
In addition, the hydraulic oil of this PTO hydraulic clutch apparatus 720 can utilize the pressure oil from the 1st charge pump unit 400a mentioned later, for example.

  In the present embodiment, as shown in FIGS. 12 and 13, the PTO hydraulic clutch device 720 has a drive side member 721 supported relative to the input shaft 370 so as not to rotate relative to the input shaft 370, and a relative rotation with respect to the input shaft 370. A friction plate including a driven side member 722 that is freely supported, a driving side friction plate that is supported by the driving side member 721 so as not to be relatively rotatable, and a driven side friction plate that is supported by the driven side member 722 so as not to be relatively rotatable. It has a group 723 and a piston member 724 that switches the friction engagement of the friction plate group 723 by the action of hydraulic pressure.

In the present embodiment, the PTO hydraulic clutch device 720 is a hydraulically operated type in which the friction plate group 723 is frictionally engaged when hydraulic oil is supplied.
Reference numeral 725 in the figure is a spring member that biases the piston member 724 in a direction away from the friction plate group 723, and prevents or reduces friction generated in the friction plate group 723 when hydraulic fluid is not supplied. It is prepared to make it.

Preferably, the PTO transmission mechanism 710 includes a PTO brake device 730 that prevents the first and second PTO shafts 701 and 702 from continuing to rotate due to inertial force when the power of the PTO hydraulic clutch device 720 is cut off. Can do.
In the present embodiment, the PTO brake device 730 is a spring-operated type that applies a braking force to the driven member 722, and when hydraulic oil is supplied to the PTO hydraulic clutch device 720, The braking force is released by hydraulic oil.

Furthermore, in the present embodiment, the PTO transmission mechanism 710 includes a PTO switching device 750 interposed between the PTO hydraulic clutch device 720 and the first and second PTO shafts 701 and 702.
The PTO switching device 750 includes a counter shaft 751 that is operatively connected to a driven member 722 of the PTO hydraulic clutch device 720, and a first counter gear 752 that is rotatably supported by the counter shaft 751. A first counter gear 752 operatively connected to the first PTO shaft 701 and a second counter gear 753 movably supported by the counter shaft 751, and a second counter operatively connected to the second PTO shaft 702 A gear 753 and a shift device 760 for transmitting the rotation of the counter shaft 751 to the first counter gear 752 and / or the second counter gear 753 are provided.
The PTO switching device 750 is configured to output rotational power only from the first PTO shaft 701, output rotational power only from the second PTO shaft 702, and the first based on the operation of the shift device 760. And a state in which rotational power is output from both of the second PTO shafts 701 and 702.

As shown in FIG. 12, the hydraulic pump device 300D further includes first and second charge pump units 400a and 400b that are rotationally driven by the first and second pump shafts 320a and 320b, respectively.
The first and second charge pump units 400a and 400b are provided to supply hydraulic oil to the corresponding hydraulic pump bodies 310a and 310b, respectively.
In the present embodiment, the first charge pump unit 400a also supplies hydraulic oil to the PTO hydraulic clutch device 720 and the PTO brake device 730.

Furthermore, as shown in FIG. 12, the hydraulic pump device 300D is an auxiliary pump that is rotationally driven by at least one of the first or second pump shafts 320a and 320b (in the illustrated form, the second pump shaft 320b). A unit 800 is provided.
The auxiliary pump unit 800 is a high-pressure gear pump, for example, as shown in FIG. 12, and can be used as a hydraulic pressure source for raising and lowering the working machine.

Thus, in the work vehicle 1D, power is transmitted from the drive source 40B to the work implement 70 via the PTO shaft 701 of the hydraulic pump device 300D.
Accordingly, in the hydraulic pump device 300D, in front view, the input shaft 370 is positioned in the pump support surface 520, and the first and second PTO shafts 701 and 702 are defined by the connecting plate 580B. It is supported by the mounting frame 500B so as to be located in the space.

In the present embodiment, the hydraulic pump device in which both the first and second hydraulic pump bodies 310a and 310b are accommodated in the single pump case 330D has been described as an example. The form is not limited.
That is, as the hydraulic pump device, a pair of first and second hydraulic pump devices supported by the mounting frame independently of each other can be provided.
In such an aspect, the first and second hydraulic pump devices are fluidly connected to the first and second hydraulic motor devices, respectively, and at least one of the first and second hydraulic pump devices is connected to the first and second hydraulic pump devices. A PTO shaft capable of outputting rotational power from the input shaft is provided.

Embodiment 5
Below, 5th Embodiment of the HST unit which concerns on this invention is described, referring an accompanying drawing.
FIG. 14 is a side view of a working vehicle 1E to which the HST unit 100E according to the present embodiment is applied.
15 and 16 are a longitudinal front view of the HST unit 100E along the XV-XV line in FIG. 14 and a transverse plan view of the HST unit 100E along the XVI-XVI line in FIG. 15, respectively. .
In addition, in the figure, the same code | symbol is attached | subjected to the same member in the said Embodiment 1-4, and the description is abbreviate | omitted.

  The HST unit 100E according to the present embodiment constitutes a traveling system continuously variable transmission mechanism of the work vehicle 1E, and the PTO transmission from the drive source 40B to the work implement 70, as in the fourth embodiment. It also constitutes part of the path.

  Specifically, the working vehicle 1E includes the vehicle frame 30, the drive source 40B supported by the vehicle frame 30, the HST unit 100E according to the present embodiment, and the drive source 40B to the HST unit 100E. Travel system power transmission mechanism 10E for transmitting power to the first drive wheel 50a and the second drive wheel 50b, the caster wheel 60, the work implement 70, and the HST unit 100E to the work implement 70. The power transmission mechanism 20D for transmitting power and the duct 80 are provided.

  The HST unit 100E is a hydraulic pump device 300E that is operatively connected to the first hydraulic motor device 200a, the second hydraulic motor device 200b, and the drive source 40B, and includes the first and second hydraulic motor devices. The hydraulic pump device 300E that is fluidly connected to 200a and 200b and that can output rotational power toward the working machine 70, the first and second hydraulic motor devices 200a and 200b, and the hydraulic pump device 300E are supported. And an attachment frame 500E that can be attached to the vehicle frame 30 in a state.

  Similar to the hydraulic pump device 300D in the fourth embodiment, the hydraulic pump device 300E rotationally drives the first and second hydraulic pump bodies 310a and 310b by the power from the drive source 40B, and the drive source The power from 40B can be output outward from the PTO shaft 700.

  That is, the hydraulic pump device 300E includes an input shaft 370 operatively connected to the drive source 40B, the first and second pump shafts 320a and 320b, and the input shaft 370 to the first and second pump shafts 320a. , 320b, a transmission mechanism for transmitting power, first and second hydraulic pump bodies supported so as not to rotate relative to the first and second pump shafts 320a and 320b, and rotational power to the outside. An output PTO shaft 700, a PTO transmission mechanism for transmitting power from the input shaft 370 to the PTO shaft 700, the first hydraulic pump body, the second hydraulic pump body, the traveling transmission mechanism, and the PTO While accommodating the transmission mechanism, the input shaft 370, the first pump shaft 320a, the second pump shaft 320b, and the PTO shaft 700 rotate around their axes. And a pump case supporting the.

In the present embodiment, the hydraulic pump device 300E further includes at least one charge pump unit 400 and at least one cooling fan 430.
The charge pump unit 400 is rotationally driven by the first or second pump shafts 320a and 320b.
Similarly, the cooling fan 430 is rotationally driven by the first or second pump shafts 320a and 320b.
In the illustrated embodiment, the charge pump unit 400 is rotationally driven by the first pump shaft 320a, and the cooling fan 430 is rotationally driven by the second pump shaft 320b.

The PTO transmission mechanism is a PTO hydraulic clutch device 720 that can selectively transmit or block the power from the input shaft 370 to the PTO shaft 700, as in the fourth embodiment (see FIG. 14). Can be provided.
Preferably, the PTO transmission mechanism includes a PTO brake device that prevents the PTO shaft 700 from continuing to rotate due to inertial force when the power of the PTO hydraulic clutch device is cut off, as in the fourth embodiment. Can do.

  14 to 16, the mounting frame 500E includes the first side plate 550a that constitutes the first motor support surface 510a, the second side plate 550b that constitutes the second motor support surface 510b, A first connecting plate 581E extending in the vehicle width direction in a substantially vertical state so as to connect one side of the first and second side plates 550a, 550b in the vehicle front-rear direction (the front side in the illustrated embodiment); A second connecting plate 582E extending in the vehicle width direction in a substantially vertical state so as to connect the other side of the first and second side plates 550a, 550b in the vehicle front-rear direction (rear side in the illustrated form); The first and second side plates 550a and 550b and the top and bottom plates 560E extending substantially horizontally to connect the upper ends of the first and second connection plates 581E and 582E.

  The mounting frame 500E includes the hydraulic pump device 300E in a space surrounded by the first side plate 550a, the second side plate 550b, the first connection plate 581E, the second connection plate 582E, and the top plate 560E. I support it.

In the present embodiment, as shown in FIGS. 14 to 16, the pump support surface on which the inner surface of the second connection plate 582E facing the first connection plate 581E supports the hydraulic pump device 300E. 520.
Specifically, the second connecting plate 582E is provided with an opening through which the input shaft 370 can be inserted.
The second connecting plate 582E is formed so that the input shaft 370 protrudes outward in the horizontal direction and from the space toward the drive source 40B through the opening. The hydraulic pump device 300E is supported on the surface.

  As shown in FIGS. 14 to 16, the first connecting plate 581E is provided with openings 585a and 585b through which the link mechanisms 37a and 37b are inserted, respectively, and an opening 586 through which the transmission shaft 29 is inserted. ing.

In the present embodiment, the rotation axis of the input shaft 370 is directed in the vehicle front-rear direction in the same manner as the drive shaft 41 in the drive source 40B, but the axis position is the drive shaft 41. Is offset in the vehicle width direction.
Accordingly, the traveling system power transmission mechanism 10 </ b> A is a pulley / belt transmission mechanism including the traveling drive pulley 11, the traveling driven pulley 12, and the traveling belt 13.

In the present embodiment, the hydraulic pump device in which both the first and second hydraulic pump bodies 310a and 310b are accommodated in a single pump case has been described as an example. It is not limited to.
That is, as the hydraulic pump device, a pair of first and second hydraulic pump devices supported by the mounting frame independently of each other can be provided.
In such an aspect, the first and second hydraulic pump devices are fluidly connected to the first and second hydraulic motor devices, respectively, and at least one of the first and second hydraulic pump devices is connected to the first and second hydraulic pump devices. A PTO shaft capable of outputting rotational power from the input shaft is provided.

In each of the embodiments, the first and second hydraulic pump bodies 310a and 310b are fluidly connected to the first and second hydraulic motor bodies 210a and 210b, respectively, as an example. Although described, the present invention is not limited to such a form.
That is, the first and second hydraulic motor bodies 210a and 210b can be fluidly connected by a pair of motor side pipes, and the pair of motor side pipes and a single traveling hydraulic pump body can be fluidly connected. It is.
For example, any one of the first and second hydraulic pump bodies 310a and 310b in each of the above embodiments can be used as the traveling hydraulic pump body.
In this case, it is possible to delete the other of the first and second hydraulic pump bodies 310a and 310b, or connect the other of the first and second hydraulic pump bodies 310a and 310b to another hydraulic device. It can also be used as a hydraulic source.

FIG. 1 is a schematic side view of a working vehicle to which an HST unit according to Embodiment 1 of the present invention is applied. FIG. 2 is a partial rear view of the working vehicle shown in FIG. FIG. 3 is a longitudinal rear view of the vicinity of the first hydraulic motor device in the HST unit. FIG. 4 is a longitudinal rear view of the vicinity of the hydraulic pump device in the HST unit. FIG. 5 is a schematic side view of a working vehicle to which the HST unit according to Embodiment 2 of the present invention is applied. FIG. 6 is a partial rear view of the working vehicle shown in FIG. FIG. 7 is a schematic side view of a working vehicle to which the HST unit according to Embodiment 3 of the present invention is applied. FIG. 8 is a partial rear view of the working vehicle shown in FIG. FIG. 9 is a schematic side view of a working vehicle to which the HST unit according to Embodiment 4 of the present invention is applied. 10 is a partial rear view of the working vehicle shown in FIG. FIG. 11 is a longitudinal rear view of the hydraulic pump device of the HST unit according to the fourth embodiment. 12 is a cross-sectional view taken along line XII-XII in FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. FIG. 14 is a schematic side view of a working vehicle to which the HST unit according to Embodiment 5 of the present invention is applied. FIG. 15 is a longitudinal front view of the HST unit taken along line XV-XV in FIG. FIG. 16 is a cross-sectional plan view of the HST unit along line XVI-XVI in FIG.

Explanation of symbols

100A to 100E HST units 200a, 200b First and second hydraulic motor devices 210a First hydraulic motor main body 220a First motor shaft 230a First motor case 255a First hydraulic motor side hydraulic fluid passages 300A, 300D, 300E Hydraulic pump device 310a 310b First and second hydraulic pump bodies 330A, 330D Pump cases 355a, 355b First and second hydraulic pump side hydraulic fluid passages 370 Input shafts 480a, 480b First and second hydraulic fluid pipings 500A-500E Mounting frame 510a, 510b First and second motor support surfaces 520 Pump support surface 600 PTO clutch device 700 PTO shafts 701 and 702 First and second PTO shafts

Claims (10)

A first hydraulic motor device that operatively drives one of the pair of drive wheels;
A second hydraulic motor device that operatively drives the other of the pair of drive wheels;
A hydraulic pump device operatively connected to a drive source, wherein the hydraulic pump device forms a traveling system continuously variable transmission mechanism in cooperation with the first and second hydraulic motor devices;
An HST unit comprising: an attachment frame that supports the first hydraulic motor device, the second hydraulic motor device, and the hydraulic pump device, and is attachable to a vehicle frame. The hydraulic pump device includes an input shaft operatively connected to a drive source, first and second hydraulic pump bodies operatively driven by power from the input shaft, and the first and second hydraulic pump bodies. A pump case for accommodating a first hydraulic pump side hydraulic fluid passage having one end fluidly connected to the first hydraulic pump main body and the other end opened to the outer surface, and one end being the second hydraulic pump main body And a pump case including a second hydraulic pump side hydraulic fluid passage that is fluidly connected to the other end and that is open at the other end thereof.
The first hydraulic motor device houses a first motor shaft that operatively drives the one drive wheel, a first hydraulic motor body that rotationally drives the first motor shaft, and the first hydraulic motor body. A first motor case including a first hydraulic motor side hydraulic fluid passage having one end fluidly connected to the first hydraulic motor main body and the other end opened to the outer surface. ,
The second hydraulic motor device houses a second motor shaft that operatively drives the other drive wheel, a second hydraulic motor body that rotationally drives the second motor shaft, and the second hydraulic motor body. A second motor case including a second hydraulic motor side hydraulic fluid passage having one end fluidly connected to the second hydraulic motor main body and the other end opened to the outer surface. ,
The HST unit is
A first hydraulic oil pipe that fluidly connects the first hydraulic pump side hydraulic oil path and the first hydraulic motor side hydraulic oil path;
A second hydraulic oil pipe that fluidly connects the second hydraulic pump side hydraulic oil path and the second hydraulic motor side hydraulic oil path;
The HST unit according to claim 1, wherein the first and second hydraulic oil pipes are supported by the mounting frame. The hydraulic pump device includes first and second hydraulic pump devices that can be arranged independently of each other,
Each of the first and second pump devices includes an input shaft that is operatively connected to the drive source, a hydraulic pump body that is operatively driven by power from the input shaft, and a pump that houses the hydraulic pump body A pump case including a hydraulic pump side hydraulic fluid passage having one end fluidly connected to the hydraulic pump main body and the other end opened to the outer surface;
The first hydraulic motor device houses a first motor shaft that operatively drives the one drive wheel, a first hydraulic motor body that rotationally drives the first motor shaft, and the first hydraulic motor body. A first motor case including a first hydraulic motor side hydraulic fluid passage having one end fluidly connected to the first hydraulic motor main body and the other end opened to the outer surface. ,
The second hydraulic motor device houses a second motor shaft that operatively drives the other drive wheel, a second hydraulic motor body that rotationally drives the second motor shaft, and the second hydraulic motor body. A second motor case including a second hydraulic motor side hydraulic fluid passage having one end fluidly connected to the second hydraulic motor main body and the other end opened to the outer surface. ,
The HST unit is
A first hydraulic oil pipe that fluidly connects the hydraulic pump side hydraulic fluid passage and the first hydraulic motor side hydraulic fluid passage in the first pump device;
A second hydraulic oil pipe that fluidly connects the hydraulic pump side hydraulic fluid passage and the second hydraulic motor side hydraulic fluid passage in the second pump device;
The HST unit according to claim 1, wherein the first and second hydraulic oil pipes are supported by the mounting frame. The hydraulic pump device is an input shaft that is operatively connected to a drive source, a traveling hydraulic pump body that is operatively driven by power from the input shaft, and a pump case that houses the traveling hydraulic pump body. A pump case including a hydraulic pump side hydraulic fluid passage having one end fluidly connected to the traveling hydraulic pump main body and the other end opened to the outer surface;
The first hydraulic motor device houses a first motor shaft that operatively drives the one drive wheel, a first hydraulic motor body that rotationally drives the first motor shaft, and the first hydraulic motor body. A first motor case including a first hydraulic motor side hydraulic fluid passage having one end fluidly connected to the first hydraulic motor main body and the other end opened to the outer surface. ,
The second hydraulic motor device houses a second motor shaft that operatively drives the other drive wheel, a second hydraulic motor body that rotationally drives the second motor shaft, and the second hydraulic motor body. A second motor case including a second hydraulic motor side hydraulic fluid passage having one end fluidly connected to the second hydraulic motor main body and the other end opened to the outer surface. ,
The HST unit is
Motor side piping for fluidly connecting the first and second hydraulic motor side hydraulic fluid passages;
A hydraulic oil pipe that fluidly connects the hydraulic pump side hydraulic oil path and the motor side pipe;
The HST unit according to claim 1, wherein the motor side pipe and the hydraulic oil pipe are supported by the mounting frame.   5. The HST according to claim 4, wherein the hydraulic pump device further includes another hydraulic pump body housed in the pump case so as to be operatively driven by power from the input shaft. unit.   The mounting frame, when mounted on the vehicle frame, is positioned above the first and second motor support surfaces, the first and second motor support surfaces located on one side and the other side in the vehicle width direction, and The HST according to any one of claims 2 to 5, wherein the HST has a front portal shape including a pump support surface positioned between the first and second motor support surfaces in the vehicle width direction. unit.   The HST according to claim 6, wherein the pump support surface extends horizontally such that a rotation axis of the hydraulic pump main body is along a vertical direction in a state where the mounting frame is mounted on a vehicle frame. unit.   The HST according to claim 6, wherein the pump support surface extends vertically so that a rotation axis of the hydraulic pump body is along a horizontal direction in a state where the mounting frame is mounted on a vehicle frame. unit.   The mounting frame has a support surface that integrally extends downward from the pump support surface and supports a PTO clutch device that is inserted in a PTO transmission path from a drive source to a work machine. The HST unit according to claim 8, wherein: 9. The HST unit according to claim 2, wherein the hydraulic pump device further includes a PTO shaft that outputs rotational power from the input shaft to the outside.

Images