JP2512976Y2 - Oil supply device for traveling work vehicle - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention comprises a mesh case equipped with left and right rear wheel axles extending left and right through left and right side wall portions, and one side wall of this mesh case. The side plate that covers the opening provided in this section is attached to one side of the mission case, and the axle case of the rear wheel axle on one side is mounted on the outer surface of this side panel, and the upper half of the front wall of the mission case is attached. A plate member covering the opening provided on the front side of the transmission case is mounted, and a hydraulic pump and a hydraulic motor of a hydraulic transmission device for continuously changing the vehicle speed are installed on the plate member. While installing the charge pump of the transmission device so as to be driven along with the hydraulic pump, another hydraulic pump driven by the pump shaft of the hydraulic pump is installed on the rear surface of the mesh case. The traveling working vehicle you have, the oil from the honey Chillon case and Chiyajiponpu other hydraulic pump described above, the oil supply device for supplying after having cleaned by a single oil filter is relates.

[Conventional technology]

A typical conventional example of the oil supply device as described above is SAIKAI Sho 62
It is disclosed in Japanese Patent No. 26-26, and the one disclosed in this publication has an oil filter along the front-rear direction in the lower part of the case.
It is installed by inserting it from the rear end of the case. The oil supply port formed at the rear end of the oil filter outside the mesh case is connected to the outside of the other hydraulic pump on the back of the mesh case by diagonally upward piping. , Three-pronged pipe joints are provided at the same position, and leading pipes are connected from the pipe joints to the oil supply pipes connected to the other hydraulic pumps and to the charge pumps on the front side of the case. .

A typical conventional example of an oil supply device for a charge pump in a traveling work vehicle that does not have the other hydraulic pump as described above is disclosed in Japanese Utility Model Laid-Open No. Sho 62-32827, and the one disclosed in this publication is a case for a shift case. An oil filter is installed laterally on the outer surface of the front end portion as a protruding shape. An intake passage communicating with the inside of the mesh case and an oil supply passage guided in the direction of the charge pump are formed on the wall of the mesh case, and communicate with the oil inlet and the oil outlet of the oil filter.

[Problems to be solved by the invention]

Among the above-mentioned two conventional examples, the conventional example disclosed in Japanese Utility Model Laid-Open No. 62-26 discloses a problem that there are many pipe connection parts and the piping work is troublesome, and that piping outside the work vehicle is long and the damage is likely to occur. Have a point. Further, the other hydraulic pumps as described above are optional hydraulic pumps that are provided for the power steering cylinder of the vehicle or the working machine lifting cylinder, and are omitted in a working vehicle that does not have such a cylinder. The structure in which the oil is first guided from the oil filter to the other hydraulic pump section is extremely disadvantageous in reducing the cost by making the main part of the oil supply device equal to the working vehicle of the specification without the hydraulic pump.

Next, according to the conventional example disclosed in Japanese Utility Model Laid-Open No. 62-32827, since the oil filter is installed on the outer surface of the work vehicle, it is easy to perform maintenance and inspection by removing it. The oil filter installed in the system has a significant disadvantage in that it requires a casing for accommodating the other of the main body of the filter and is expensive. Further, the oil filter provided with the oil inlet and the oil outlet aligned with the suction passage and the oil supply passage on the wall of the case is the one for the other hydraulic pump in the working vehicle having the specifications for the other hydraulic pump as described above. It seems that it is impossible to use it for the first time, and even if it is possible to use the same by devising a special adapter, since the oil filter is located on the front side, Long piping will be required up to the other hydraulic pumps above.

Therefore, this invention eliminates piping between the oil filter and the charge pump and shortens piping between the oil filter and other hydraulic pumps as much as possible in the traveling work vehicle as described at the beginning, and installs the other hydraulic pump as described above. It is an object of the present invention to provide an oil supply device in which a main part of the device can be easily shared with a work vehicle having no specifications and which does not cause any problems in cost and maintenance and inspection of the filter.

[Means for solving problems]

To this end, the present invention, as illustrated in FIGS. 2 and 3, includes a mesh case 2 equipped with left and right rear wheel axles 1 that extend left and right through the left and right side walls, and one of the mesh case 2 is provided. A side plate 21 that covers the opening provided in the side wall is attached to one side surface of the mission case 2, and the axle case 20 of the rear wheel axle 1 on one side is mounted on the outer surface of the side plate 21. A plate member 3 for covering the opening provided in the upper half of the front wall portion is mounted on the front surface of the transmission case 2, and the hydraulic pump 5 and the hydraulic motor 6 of the hydraulic transmission device 4 for continuously controlling the vehicle speed are mounted on the plate. It is installed on the member 3, and the plate member 3 is equipped with the charge pump 7 of the hydraulic power transmission device 4 so as to be driven together with the hydraulic pump 5. On the other hand, the pump of the hydraulic pump 5 is mounted on the back surface of the mesh case 2. On axis 8 Another hydraulic pump driven Ri
The following technical measures were taken in the traveling work vehicle with 10 installed.

That is, as illustrated in FIG. 1, first, an oil filter 11 provided with oil supply ports 12 and 13 at both front and rear ends is inserted into a lower portion of the mission case 2 from an insertion port 14 of a back wall of the mission case.
The front end of the filter is fitted and held in a bearing hole 15 formed on the inner surface of the front wall of the motion case, and the mounting flange 16 at the rear end of the filter is detachably attached to the rear face of the motion case 2 for installation.

Then, as illustrated in FIGS. 1 and 4, an oil supply passage 17 for the charge pump 7 is provided in the plate member 3, and an upper connection passage 18 communicating with the oil supply passage 17 and the bearing hole 15 are provided. And a lower side connecting passage 19 communicated with the upper side and the lower side connecting passages 18 and 19 formed in the front wall portion of the mesh case 2 by opening to the one side surface of the mesh case 2. The spaces are communicated with each other by a vertical communication passage 22 formed between the one side surface of the mesh case 2 and the inner surface of the side plate 21.

Further, as illustrated in FIGS. 1, 9 and 10, the oil supply port 13 at the rear end of the oil filter is connected to the other hydraulic pump 10 by an oil supply pipe 23.

[Action]

For maintenance and inspection of the oil filter 11, remove the oil supply pipe 23 from the rear end of the filter 11 and attach the mounting flange 16 at the rear end.
Can be removed from the back of the case, and the oil filter 11 can be pulled out from the inside of the case 2 to the rear.

For other work vehicles that do not have the hydraulic pump 10, install a flange on the lid that closes the oil supply port 13 at the rear end of the oil filter.
A mounting flange corresponding to 16 may be provided.

〔Example〕

In the illustrated embodiment, as shown in FIG. 10, the present invention relates to a mower tractor in which a mid-mount type mower M is provided between the front wheels 25 and the rear wheels 26 provided in a pair of left and right at the lower surface of the body. , According to the example implemented.

As shown in FIG. 10, the engine 26 is mounted on the front part of the machine body, and a transmission shaft 27 that is transmitted from the engine 26 to the pump shaft 8 of the hydraulic transmission device 4 is provided along the front-rear direction. The illustrated tractor is provided with, as PTO shafts, a rear PTO shaft 28 extending rearward from inside the case 2 and a mid PTO shaft 29 extending forward. Rear PTO
The shaft 28 is used to drive a work machine such as a glass collector connected to the rear part of the machine body, and the mixed PTO shaft 29 is used to input and transmit to the gear box Ma for driving the mower M via the transmission shaft 30.

The passenger seat 31 is installed above the mission case 2 arranged between the left and right rear wheels 26, and a steering wheel 32 for steering and turning the left and right front wheels 25 is exposed in front of it. A single-acting working machine hydraulic cylinder 33 for raising and lowering a working machine such as a glass collector is provided between the mission case 2 and the passenger seat 31.

As shown in FIG. 2, the hydraulic pump 5 and the hydraulic motor 6 of the hydraulic transmission device 4, each of which is equipped with a casing, have hydraulic pressures on the back surface and the front surface of the plate member 3, which is made thick as shown in the drawing. The pump 5 is mounted on the upper side. The charge pump 7 is of a trochoid type in which the pump shaft thereof is also used as the pump shaft 8 of the hydraulic pump 5, and is mounted on the front surface of the plate member 3.

Similarly, as shown in FIG. 2, the motor shaft 9 of the hydraulic motor 6 is
Is provided with an extension shaft 34 connected inside the plate member 3, and a bevel gear 35 integrally formed at the rear end of the extension shaft 34 inputs traveling driving force from the hydraulic motor 6 into the mesh case 2. It is said that. A hollow shaft 37, which has a short length as shown in FIGS. 3 and 8, is loosely fitted and installed on the transmission shaft 36 which is horizontally installed in the mesh case 2. A bevel gear 38 meshed with the bevel gear 35 is fitted. As shown in FIGS. 2 and 8, a reduction shaft 39 is laterally installed at a rear upper position of the transmission shaft 36 in the transmission case 2. Hollow shaft
Between the 37 and the transmission shaft 36, a gear 40 fitted to the hollow shaft 37, two gears 41 and 42 fitted to the reduction shaft 39, and a shift gear spline-fitted to a spline cylinder 44 fitted to the transmission shaft 36. A reduction gear train consisting of 43 and is provided. Shift gear 43
Shifts from a position where it meshes with the gear 42 to a position where it meshes with the spline of the spline cylinder 44 and the spline on the outer surface of the hollow shaft 37 to directly connect the hollow shaft 37 and the transmission shaft 36, as shown in FIG. It is possible. Therefore, as shown in FIG. 8, the transmission shaft 36 can be switched between two high and low rotational speeds by shifting the shift gear 43 by the shift fork 45 operated from outside the transmission case 2.

As shown in FIG. 3, a differential device is provided between the left and right rear wheel axles 1.
47 is provided, and the transmission shaft 36 is a small gear 48 integrally formed with the transmission shaft 36.
And the input large gear 49 of the differential device 47, and is transmitted to the rear wheel axle 1. The transmission shaft 36 is provided with a traveling brake 50 as shown in FIGS. 3 and 8, and the differential device 47 is provided with a defrost clutch 51 as shown in FIG. The defrost clutch 51 is operated by a fork 53 on a fork shaft 52 which is laterally suspended in the case 2 as shown in FIG.

As shown in FIG. 2, the pump shaft 8 of the hydraulic transmission device 4 is also extended rearward, and the drive shaft 55 connected to the pump shaft 8 by the coupling 54 is connected to the both PTO shafts 28, 29
It is provided to drive the. The other hydraulic pump 10 is driven by the pump shaft 8 of the hydraulic transmission device 4 through the drive shaft 55 by connecting the pump shaft 10a to the drive shaft 55 by the coupling 56. There is.

Similarly, as shown in FIG.
A friction multi-plate hydraulic clutch 59, in which a plurality of friction elements are slidably supported by a clutch housing 57 fixedly installed and a gear 58 loosely installed, is installed on 55. A hydraulic oil passage for supplying hydraulic oil to the piston 60 of this hydraulic clutch 59 to achieve clutch engagement.
61 is provided in the drive shaft 55 and communicates with an annular oil chamber 63 whose outer peripheral end is sealed by a tubular portion 62 formed in the partition wall 2a in the mesh case 2.

A gear 58 on the drive shaft 55 is formed as a hollow shaft by two gears 67, 68 on an intermediate shaft 66 supported by the partition wall 2a and a lid member 65 mounted on the back of the case. It is interlockingly connected to a gear 69 loosely fitted on the rear PTO shaft 28. The rear end of the hybrid PTO shaft 29 faces below the rear PTO shaft 28, and a gear 70 meshed with the gear 69 on the rear PTO shaft 28 is loosely fitted therein. The fork 7 shown in FIG. 9 is located on the rear PTO shaft 28 and on the mixed PTO shaft 29, respectively.
Rear PTO clutch 73 and Mit P operated by 1,72
TO clutch 74 is installed.

In the illustrated mower tractor having the above-described traveling system and PTO system transmission mechanism, the oil filter 11 is located below the differential case 47 as shown in FIGS. Is slightly downwardly extended to secure a space for facing the lower end portion of the input large gear 49 of the differential device 47 and an installation space for the oil filter 11 so as to extend along the front and rear direction in the deepest portion of the mesh case 2. is set up. As shown in FIG. 1, the oil filter 11 is fitted into the bearing hole 15 at a base portion having an oil supply port 12 at the front end, and the mounting flange 16 is provided at the base portion having an oil supply port 13 at the rear end.
, And is removably attached to the rear surface of the case 2 by means of mounting bolts 24 shown in FIGS.

As shown in FIG. 4, the upper connection passage 18 is not connected to the oil supply passage 17 in the plate member 3 in the mesh case 2.
1 and 2. The front and rear passage portions are aligned at their mating surfaces with the plate member 3, and the left and right passage portions extend from their inner ends to one outer surface of the front wall of the case. As shown in FIG. 5, the lower connection passage 19 is formed so as to extend laterally from the position of the bearing hole 15 and open to the outer surface on one side of the front wall of the mesh case. These connecting passages
18 and 19 are formed at the same time as the casting of the case 2, but as shown in FIG. 2, the upper and lower connecting passages 18 and 19 are located at substantially the same position in the front-rear direction, and the side wall of the case. Is arranged so as to open to the outer surface on one side. A groove 21a is formed on the inner surface of the side plate 21 along the vertical direction, which is formed at the same time when the side plate 21 is formed by casting. As shown in FIGS. 1 and 4, the groove 21a forms a connection passage. 1
The communication passage 22 for providing communication between 8 and 19 is provided. The side plate 21 is, as shown in FIGS. 3 and 4, the axle case 20.
It is also used for supporting the transmission shaft 36, the reduction shaft 39, etc. by closing the opening for mounting the transmission on one side of the transmission case 2.

As shown in FIG. 1, an L-shaped connecting pipe 76 mounted outside the mesh case 2 is provided at the rear end of the oil filter 11, and the oil supply pipe 23 connects the lower end to the connecting pipe 76. It is guided upward as shown in FIGS. 9 and 10 and is connected to the oil intake port 10b of the other hydraulic pump 10 shown in FIG.

Before connecting a more specific structure of the oil supply device, the hydraulic circuit provided in the mower tractor will be described with reference to FIG. 11. In the oil supply path from the inside of the mesh case 2 also serving as an oil tank to the charge pump 7. The line filter
The line filter 77 is provided with a check valve 78 which is operated in parallel when the line filter 77 is clogged. Check valves 79 and 80 are inserted into the pair of oil supply circulation passages for reinforcing the oil from the charge pump 7 to the closed circuit of the hydraulic transmission device 4 as usual, but the check valves 79 and 80 shown in the figure are shown. Is an opening actuating rod 79 so that oil can be drained from the closed circuit when parking, maintenance of the hydraulic transmission device 4, inspection, etc.
It is said that it can be artificially opened by a, 80a.

The charge pump 7 is also used as a pump for supplying hydraulic oil to the hydraulic clutch 59 of the PTO system, and is a secondary side of the relief valve 81 that sets the hydraulic pressure of the oil supplied to the closed circuit of the hydraulic transmission 4. It is supposed that another relief valve 82 is provided for supplying hydraulic oil which is set by the relief valve 82 to the hydraulic clutch 59. A switching valve 83 having a neutral position N for maintaining the hydraulic clutch 59 in a cut state and an operating position I for engaging by supplying hydraulic oil is provided in the clutch oil supply path led out between the relief valves 81, 82. Has been. The switching valve 83 is biased toward the neutral position N by a spring 83a, and is operated by an operating rod 83b to operate at an operating position I.
It is supposed to be moved to.

Similarly, as shown in FIG. 11, the other hydraulic pump 10 is for supplying hydraulic oil to the power steering cylinder 84 provided in the illustrated tractor and the actuator cylinder 33 and the like illustrated in FIG. It is used, and is connected to the power steering valve mechanism 85 and the control valve 86 of the working machine cylinder 33. The power steering valve mechanism 85 is a steering valve whose displacement is operated by the steering wheel 32 shown in FIG.
85a, a metering motor 85b for automatically returning the valve 85a to a neutral state, a power steering cylinder 84, and a relief valve 85c for setting a hydraulic pressure for the metering motor 85b. Power steering valve mechanism 8
Control valve 86 of hydraulic cylinder 33 for work equipment from 5 to 86
The oil passage opening / closing valve 87 is inserted in the oil supply passage guided in the direction, and from the primary side and the secondary side of the opening / closing valve 87, for example,
Oil supply passages 88 and 89 are provided for enabling oil supply to other hydraulic cylinders such as a lifting cylinder for the mower M shown in FIG.

Most of the members inside the outline V of the two-dot chain line in FIG.
Installed on the surface of the plate member 3 and inside,
The oil passage structure in the meantime is as follows.

That is, the line filter 77 is adhered to the front surface of the plate member 3 as shown in FIGS.
The line 17 communicates with the primary side of the line filter 77. A short lengthwise passage 91 communicating with the secondary side of the line filter 77 and a passage 92 extending laterally from the passage 91 to a position below the pump shaft 8 are provided in the plate member 3, and the passage 92 is provided. The end is communicated with the suction port of the charge pump 7 by the forward passage 93 shown in FIG. As shown in FIG. 2, on the upper side of the pump shaft 8, a short-length passage 94 extending rearward from the discharge port of the charge pump 7 is formed.
A passage 95 extending upward from the passage 94 is provided in the middle of the passage 95 in the front-rear direction and the passage 97 in the left-right direction.
Therefore, as shown in FIGS. 4 and 5, the check valves 79 and 80 are connected to the primary side. The check valves 79, 80 are, as shown in FIG. 5, arranged so that the pair of oil intake / exhaust ports 5A, 5B of the hydraulic pump 5 and the pair of oil intake / exhaust ports 6A, 6B of the hydraulic motor 6 are connected to each other. Are installed in the upper ends of a pair of oil passages 98A, 98B provided along the vertical direction. The opening actuating rods 79a, 80a are held by screw plugs 79b, 80b screwed to the upper end of the plate member 3 by an O-ring which also serves as a seal member, and pushed downward from the position shown in FIG. Then, the check valves 79 and 80 are opened.

As shown in FIGS. 2 and 6, the relief valve 81 is installed in the upper end portion of the passage 95. A lateral passage 100 is formed in the plate member 3 on the secondary side of the relief valve 81.
One end of the relief valve 82 is communicated with the inside of the case 2, and the relief valve 82 is installed in the same end. Further, as shown in FIGS. 5 and 7, a valve insertion hole 101 for opening the passage 100 is formed in the plate member 3 from the upper surface side, and the switching valve 83 is inserted and installed in the valve insertion hole 101. As shown in FIGS. 4 and 7, the inside of the valve insertion hole 101 is provided with a plate member 3 for one side wall of the mesh case 2 by a passage 102 in the front-rear direction, a passage 103 in the downward direction, and a passage 104 in the rearward direction. Is opened on the mating surface and is opened on the lower side in the mesh case 2 by a passage 105 shown by a broken line in FIG. At the position shown in FIGS. 5 and 7, the switching valve 83 connects the passages 100 and 105 to drain the oil from the passage 100 into the mesh case 2, and is integrally formed to project upward. Push in the rod 83b to connect the passages 100 and 102,
Oil is supposed to be guided from the passage 100 to the passage 104 side. The operating rod 83b is held by a screw plug 83c screwed to the plate member 3 via an O-ring.

The above-mentioned passage 104 is arranged at the same level as the pump shaft 8 and the drive shaft 55, and one side wall of the movement case 2 has a front end opening which is aligned with the passage 104 as clearly shown in FIG. A rearward-facing passage 107 is formed. Then, a lateral wall portion 2b integral with the partition wall 2a shown in FIG. 2 is formed on the inner surface of the mesh case 2 as shown in FIGS. 3 and 4, and the cylindrical portion 62 is formed at the end thereof. In addition, a lateral passage 108 that connects the passage 107 to the annular oil chamber 63 is formed in the wall 2b.

In FIG. 3, reference numeral 5a denotes a pump swash plate for changing the volume of the hydraulic pump 5, which is usually of a variable displacement type, and an operating shaft 110 rotatably supported on the side wall of the mesh case 2. The tilt angle is controlled to be changed via a control arm 111 attached to the outer end of the control arm 111.

The mower tractor shown in the drawing is driven by driving the rear wheels 26, and the vehicle speed is changed and controlled by the tilt angle control of the pump swash plate 5a of the hydraulic transmission 4 and the high and low two-stage control by the shift gear 43 shown in FIG. Meanwhile, it is used for various work.

At the time of lawnmower work using the mower M shown in FIG.
When the grass PTO clutch 74 shown in FIG. 2 is put in, and at the same time, grass reaped by the grass collector at the rear of the vehicle which is transmitted from the rear PTO shaft 28 is collected, the rear PTO clutch 73 shown in FIG. 2 is also included. Can be put in. Rear PTO axis 28
Is a fertilizer applicator that is connected to the rear of the vehicle, such as when performing stationary work such as pest control work using the power of the engine 13.
It is used to extract the necessary power when performing work with a seeder. When operating the rear PTO clutch 73 or the mixed PTO clutch 74 before or after work,
Prior to that, the hydraulic clutch 59 is turned off.

[Effect of device]

In this invention, a plate member 3 mounted on the front face of a mesh case 2 is equipped with a hydraulic pump 5 of a hydraulic transmission device 4, a hydraulic motor 6 and a charge pump 7, and another hydraulic pressure driven by a pump shaft 8 of the hydraulic pump 5. In a traveling work vehicle in which the pump 10 is installed on the rear surface of the mission case 2, an oil filter capable of taking out the cleaning oil from the oil supply ports 12 and 13 at the front and rear ends in correspondence with the front and rear arrangement of the charge pump 7 and the other hydraulic pump 10. 11 is installed along the front and back in the lower part of the mission case, and on the front wall of the mission case 2,
A connection passage 18 communicated with the oil supply passage 17 for the charge pump in the plate member 3 on the upper side and the lower side and a connection passage 19 communicated with the oil supply port 12 at the front end of the filter are connected to the front wall of the mesh case. It is formed by opening on one side surface of each of the case cases, and a side plate 21 to which the axle case 20 of the rear wheel axle 1 on one side is attached is provided between the inner surface of the side plate 21 and the one side surface as described above. A communication passage 22 is formed to connect the connection passages 18 and 19, and the oil supply port 13 at the rear end of the filter is connected to another hydraulic pump 10 on the rear surface of the mesh case by an oil supply pipe 23 on the rear side of the case. Therefore, piping between the oil filter 11 and the charge pump 7 is eliminated on the front side of the mission case 2 without adding a special member, and piping on the rear side of the mission case 2 is as short as possible. Oil of And summer to that forming the oil supply passage required for the pump 10, the effect to remove the adverse effects of the use of long piping with a simple structure of the oil supply device.

In addition, the oil filter 11 is inserted through the insertion hole 14 in the back wall of the motion case, and the bearing hole 15 in the inner wall of the front wall of the motion case is inserted.
The front end is fitted and held in the rear end, and the rear end mounting flange
Due to the structure that is detachably attached to the back of the case by means of 16, the mounting flange 16 is used to attach the oil supply port to the work vehicle of the specification without the other hydraulic pump 10.
The main part of the oil supply device can be made common only by changing the one that has a lid for closing 13 and maintenance and inspection of the oil filter 11 can be easily done by pulling out the filter 11 to the back side of the mesh case 2. However, since the oil filter is installed in the mission case, the casing for the filter is not required, and the cost does not occur.

[Brief description of drawings]

FIG. 1 is a partially exploded cross-sectional plan view of a main part of a traveling work vehicle equipped with an embodiment of the present invention, and FIG. 2 is a partially cutaway, partially expanded longitudinal side view of the main part of the same work vehicle. The drawing is a cross-sectional view substantially along the line III-III in FIG. 2, FIG. 4 is a partially exploded cross-sectional plan view of the main part of the work vehicle, and FIGS. 5 and 6 are V- of FIG. 2 respectively.
FIG. 7 is a sectional view taken along line VII-VII of FIG. 5, FIG. 8 is a sectional view of a portion of the work vehicle, and FIG. 9 is shown in FIG. 2 is a partially omitted sectional view substantially along the line IX-IX in FIG. 2, FIG. 10 is a schematic side view of the traveling working vehicle equipped with the illustrated embodiment, with some cutouts, and FIG. 11 is provided in the working vehicle. It is a circuit diagram of a hydraulic circuit. 1 ... Rear wheel axle, 2 ... Mission case, 3 ... Plate member, 4 ... Hydraulic transmission device, 5 ... Hydraulic pump, 6
…… Hydraulic motor, 7 …… Charge pump, 8 …… Pump shaft, 10 …… Other hydraulic pump, 11 …… Oil filter, 12,13
…… Oil supply port, 14 …… Insertion hole, 15 …… Bearing hole, 16 …… Mounting flange, 17 …… Oil supply passage, 18 …… Upper side connection passage, 19 …… Lower side connection passage, 20 …… Axle case, 21
...... Side plate, 21a ...... Concave groove, 22 ...... Communication passage, 23 ...... Oil supply pipe, 24 ...... Mounting bolt, 76 ...... Connection pipe, 77 ...... Line filter, 91,92,93 ...... Passage.

Claims (1)

(57) [Scope of utility model registration request] 1. A miss case 2 equipped with left and right rear wheel axles 1 extending left and right through left and right side walls, and a side plate 21 for covering an opening provided in one side wall of the miss case 2. The axle case of the rear axle 1 on one side is mounted on the outer surface of the side plate 21 by being mounted on one side of the mission case 2.
In addition to mounting 20, a plate member 3 for covering the opening provided in the upper half of the front wall of the transmission case 2 is mounted on the front surface of the transmission case 2 to provide a hydraulic transmission device 4 for continuously controlling the vehicle speed. A hydraulic pump 5 and a hydraulic motor 6 are installed on the plate member 3, and the charge pump 7 of the hydraulic transmission device 4 is mounted on the plate member 3 so as to be driven together with the hydraulic pump 5, while the shift case 2 In a traveling work vehicle in which another hydraulic pump 10 driven by the pump shaft 8 of the hydraulic pump 5 is installed on the rear surface of the vehicle, an oil filter 11 having oil supply ports 12 and 13 at both front and rear ends is provided in a shift case. From the insertion port 14 of the back wall of the motion case to the lower part of 2, the front end of the filter is fitted and held in the bearing hole 15 provided on the inner surface of the front wall of the motion case, and the mounting flange 16 at the rear end of the filter is used. An oil supply passage 17 for the charge pump 7 is provided in the plate member 3 so as to be removably mounted on the back surface of the cushion case 2 and installed, and an upper connection passage 18 communicating with the oil supply passage 17 and the above-mentioned connection passage 18 are provided. A lower connecting passage 19 communicating with the bearing hole 15 is formed in the front wall portion of the mesh case 2 by opening at the one side surface of the mesh case 2, and these upper and lower connecting passages are formed. 18 and 19 are communicated with each other by a vertical communication passage 22 formed between the one side surface of the shift case 2 and the inner surface of the side plate 21, while the oil supply port 13 at the rear end of the oil filter is connected. Other hydraulic pumps
An oil supply device that is connected to 10 by an oil supply pipe 23.