JPH01223023A - Axle drive - Google Patents

Abstract

PURPOSE:To reduce both the size and the weight of an axle drive by forming both a pump mounting face on the bottom wall of a transmission case and a mode mounting face on a vertical wall and also forming two oil passages which connect a hydraulic pump to a hydraulic mode to each other, in the bottom wall and the vertical wall. CONSTITUTION:An HST speed change gear consisting of a hydraulic pump P and a hydraulic motor M which drive left and right axles is contained in one of left and right transmission cases 1 and 2, the other of which support the left and right axles. In this case a hydraulic pump mounting face 1b is formed on the bottom wall 1a of the left transmission case 1 as to vertically mount a pump shaft 4 and a vertical wall 1i is also formed adjacently to the face 1b. A motor mounting face 1j is formed on the vertical wall 1i as to place a motor shaft 5 in parallel with each axle and decentered from the pump shaft 4. Two oil passages 1e, 1f and 1h connecting the hydraulic pump P and the hydraulic motor M to each other are formed in the bottom wall 1a and the vertical wall 1i.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an axle drive device used as a propulsion device for a tractor.

(B) Prior Art Conventionally, there is a known drive device in which a transmission case for driving an axle is divided into two parts, an axle bearing part is provided in the transmission case, and an H3T3f speed device is attached to the side or top surface of the mission case. It has become. For example, it is disclosed in Japanese Utility Model Publication No. 62-44198 by the same applicant.

(c) Problems to be solved by the invention However, with the conventional configuration, in order to attach the H3T3f speed device separate from the transmission case, the HS
The Type 7 transmission protrudes from the transmission case,
It was necessary to provide extra space.

Additionally, if the HS7 type transmission is externally attached, piping is required between the two if the lubricating oil inside the transmission case is to be used as hydraulic oil for the HST type transmission.
Filters, etc., were also needed, and space needed to be secured for them.

(d) Means for solving the problem In view of the above, the present invention provides an H in the mission case.
It is constructed as follows in order to house the S7 type transmission, filter, etc., and to provide an oil passage in the wall of the transmission case.

In a configuration in which a hydraulic pump and a hydraulic motor for driving the axle are installed on the inner wall of a mission case that supports an axle, the pump shaft is vertically installed on the bottom wall of the mission case (which forms the mounting surface for the hydraulic pump). , a vertical wall is provided adjacent to the hydraulic pump mounting surface, and the motor mounting surface is arranged on the vertical wall so that the motor shaft is parallel to the axle and the shaft center position is aligned with the pump shaft when viewed from above. and two oil passages connecting the hydraulic pump and the hydraulic motor to each other are formed in the bottom wall and the vertical wall.

In addition, two oil passages on the hydraulic pump side drilled in the bottom wall of the mission case are opened on the vertical wall side, and a check valve that can be opened toward the core oil passage is provided at each open end. It is something.

Further, the check valve is composed of a valve holder having a ball and a valve seat, and a filter is disposed so as to fit into a lubricating oil suction hole formed in the valve holder.

In addition, the valve holder on the opposite side of the valve seat is formed into a hollow pipe shape, and a ball push rod with a tapered tip that is slidably guided is installed inside the valve holder, and the above-mentioned ball push rod is installed at the outer peripheral position of the tapered portion. In addition to forming a lubricating oil suction hole, an operating rod for integrally operating the ball pushing rod is protruded from the outside of the transmission case.

Further, the two oil passages on the hydraulic motor side are bored below the upper end surface of the vertical wall of the transmission case, and communicated with the two oil passages on the hydraulic pump side in the bottom wall running in the horizontal direction. The oil passage drilled in the upper end surface is covered with a lid that supports the pump shaft.

(E) Embodiments The objects of the present invention are as described above, and the present invention will be explained in detail based on the configuration of the embodiments shown in the accompanying drawings.

FIG. 1 is a rear sectional view of the axle drive device of the present invention.

FIG. 2 is a sectional view taken along line XX in FIG. 1. FIG. 3 is a YY cross-sectional view in FIG. 1. FIG. 4 is a side view of the motor mounting surface.

The mission case of the axle drive device is divided into a left mission case 1 and a right mission case 2, and an H3T3f speed device consisting of a hydraulic pump P, a hydraulic motor M, etc. is installed on one side of the left mission case 1 and right mission case 2. , the axles 13L and 13R and the differential gear device are internally supported on the other sides of the left-hand transmission case 1 and the right-hand transmission case 2.

That is, a pump mounting surface 1b is formed on the bottom wall 1a on the left mission case 1 side, a semicircular oil passage IC 1d is bored in the pump mounting surface 1b, and a pump shaft is installed in the center of the pump mounting surface 1b. 4 are installed vertically.

A cylinder block 10 is externally fitted onto the pump shaft 4, and springs 3, 3, and so on are installed inside the cylinder block lO, and biased pistons 12, 12, and so on are attached to the pump shaft 4.
The upper ends of the pistons 12, 12, . The slope of the swash plate 9 is changed by the rotation of an arm 7 projecting from a speed change lever shaft 6 that is pivotally supported by the left transmission case 1, and the amount and direction of pressure oil discharged are changed.

The top of the swash plate 9 is covered with the lid 34, and the top of the pump shaft 4 is supported. A detent device 20 is provided on the lower surface of the lid 34, and by fitting into a notch provided in the arm 7, the detent device 20 can be held at a neutral position.

Therefore, when the pump shaft 4 is rotated, the cylinder block 10 is rotated, and the pistons 12, 12, . . .
The oil expands and contracts by an amount corresponding to the inclination of the oil passages 1e and 1d, and suction and discharge are performed from the oil passages 1e and 1d.

A standing wall 1i is erected adjacent to the bottom wall 1a, and the standing wall 1
Motor mounting surface 1j on the side of right transmission case 2 of i
is provided between the central part of the motor mounting surface 1j and the standing wall 2a of the right side transmission case 2, parallel to the axles 13L and 13R, and separated from the pump shaft 4 by a distance of ΔH when the axis position is viewed from above. The motor shaft 5 is horizontally mounted so that the motor shaft 5 is mounted horizontally.

A cylinder block 1i is fitted onto the motor shaft 5, and springs 29, 29,
Pistons 14, 14, . . . , which are energized by .
6, and the thrust bearing 16 is fixed to a fixed swash plate 32.

In addition, oil passages 1e and 1f are formed horizontally in the bottom wall 1a in a tapered shape toward the right transmission case 2 side, and the oil passage 1f directly communicates with the oil passage 1e, and the oil passage 1e is formed on the upper surface of the bottom wall 1a. It is communicated with the oil passage IC via an oil passage 1e' which is perforated in a direction perpendicular to the view. And nuclear oil road 1e/1f
Check valves 26 and 27 are provided at the open end on the right side of the transmission case 2, as shown in FIG.
6b and 27b, and the valve holder 26b and 27
b is constructed in the shape of a hollow pipe, and valve seats 26c and 27c are formed inside the oil passages 1e and lf, and balls 26a and 27a are releasably inserted into the oil passages 1e and if. Removal stops 38 and 39 for the valve holder 27a are interposed between the vertical wall 1i and the bulb holders 26b and 27b.

Ball push rods 35, 36 are slidably inserted into the valve holders 26b, 27b, and tips 35 of the ball push rods 35, 36 on the valve seats 26c, 27c side
a and 36a are formed into a tapered shape, and the tips 35a and 36a
the balls 26a and 27 in the direction away from the valve seat 26c27C.
The valve can be opened by pressing a. The ball push rod 3
The other ends of 5 and 36 are brought into contact with the pressing portion 37a of a T-shaped operating rod 37, and the operating rod 37 is pushed to open the check valves 26 and 27 when towing a vehicle equipped with an H3T transmission. Pressure oil is removed to allow the motor shaft 5 to rotate easily, so that no load is placed on the H3T type transmission.

Also, the tips 35a and 36 of the ball push rods 35 and 36 are
Lubricating oil suction holes 26d and 27d are opened on the side surfaces of the valve holders 26b and 27b located on the outer periphery of a, and filters 30 and 31 are fitted to cover the suction holes 26d and 27d to filter the lubricating oil. It is used as hydraulic oil for the H3T transmission.

The vertical wall 1i has oil passages 1g and 1h tapered from the top surface.
is bored, and the lower end is connected to the oil passage 1e, as shown in FIG.
1r, and communicates with oil passages 1m and 1n formed in a half-moon shape on the motor mounting surface 1j at the midway side surface, and the open hole at the upper end is covered with a lid 34.

Therefore, the oil passages 1m-1n are communicated from the oil passage 1em1d through the oil passage 1em1f horizontally bored in the bottom wall 1a and the oil passages 1g and 1h vertically bored in the vertical wall. Then, the pressure oil from the hydraulic pump P is transferred to the piston 14 from the oil passages 1e, Ic', 1e, 1g, and 1m.
・14..., the cylinder block 1i is rotated, and the oil passages 1n, 1h, 1 are connected from the pistons 14, 14...
r・1d and oil is sent to the piston 12・1 of the hydraulic pump P.
2... or sent in the opposite direction,
Pressure oil from the hydraulic pump P pushes the pistons 14, 14, . . . to rotate the motor shaft 5. And H.S.
If the hydraulic oil of the Type 7 transmission leaks, the check valve 26.2
It will be replenished from 7 onwards.

The rotation of the motor shaft 5 is transmitted from a gear 17 carved on the motor shaft 5 to a large diameter gear 21 on a counter shaft 24 that meshes with the gear 17, and then to a small diameter gear 21 carved on the counter shaft 24. Power is transmitted from 22 to the ring gear 23 of the differential gear device, and the axles 13L and 13R, which project from the differential gear device to the left and right, are driven.

A brake drum 18 is fixed to the end of the motor shaft 5 protruding into the open portion 2b of the right transmission case 2, and the brake drum 18 is rotated by the rotation of a brake arm 19 pivotally supported by the lid body 33. It is configured to be braked by forceful contact. The oil passage 1elc' If・
The Iglh is formed by a tapered casting process, which is done together with the forming process of the left transmission case 1, eliminating the need for special machining such as drilling holes.

(F) Effects of the Invention With the above-described configuration, the present invention provides the following effects.

First, since the 837-type transmission that drives the axle is housed inside the transmission case, there is no need for space to securely install the HST-type transmission outside the transmission case, as in the past. This made it possible to reduce the size and weight of the device.

Second, because the oil passages for the hydraulic pump and hydraulic motor are formed directly on the transmission case without using an oil passage plate, the entire axle drive system can be made smaller, saving space for installation on the tractor body. It became possible to have a smaller size.

Third, although the pump shaft is perpendicular to the axle as in the prior art, the oil passage formed in the transmission case is communicated in the perpendicular direction without interposing a bevel gear device. The direction of power transmission to the hydraulic motor can be changed at right angles, and in the case of small tractors equipped with an engine with a vertical crankshaft, power can be easily input to the hydraulic pump using a pulley and belt. This is what became.

Fourthly, since the pump mounting surface and the motor mounting surface are formed so that the pump shaft and the motor shaft are arranged so that their shaft centers are aligned when viewed from above, the hydraulic pump and the hydraulic motor can be connected to each other. One of the two oil passages is an oil passage 1 drilled horizontally in the bottom wall between the semicircular oil passage on the pump shaft mounting surface and the semicircular oil passage on the motor mounting surface.
Since the oil passage 1h can be connected to the gray left by the oil passage 1h vertically bored in the vertical wall, the oil passage can be simplified and constructed at low cost.

Fifth, since the check valve is provided on the open side of the oil passage drilled in the horizontal direction, it can be used in place of a plug, and there is no need to provide a new oil passage for the check valve.

Sixth, since the filter is fitted into the valve holder,
Saves space for installing a filter,
The oil passage configuration for the filter could be simplified and the filter could be installed at low cost.

Seventh, since a pole push rod is provided inside the valve boulder to open the check valve, there is no need to newly install a bypass valve for the hydraulic circuit of the 837 transmission.
This made it possible to reduce the number of parts and simplify the oil passage.

Eighth, since the oil passage is formed from the upper surface of the vertical wall, it is easier to form the oil passage, and since the open part of the kernel oil passage is covered with a lid instead of being plugged, the number of parts can be reduced, and the number of parts can be reduced. The number of man-hours could also be reduced.

[Brief explanation of the drawing]

FIG. 1 is a rear sectional view of the axle drive device of the present invention. FIG. 2 is a sectional view taken along line XX in FIG. 1. FIG. 3 is a YY cross-sectional view in FIG. 1. FIG. 4 is a side sectional view of the motor mounting surface. M...Hydraulic motor P...Hydraulic pump 2...Mission case 1a...Bottom wall 1i...Vertical wall IC/If-1g/1h...Oil passage 1b...Pump mounting surface 1j/ ...Motor mounting surface 4...Pump shaft 5...Motor shaft 13...Axle shafts 26, 27...Check valves 26a, 27a...Balls 26b, 27b...Valve holders 26c, 27c...・Valve seats 26d, 27d...Suction holes 30, 31...Filter 34...Cover body 35, 36...Ball push rod 37...Operating rod Applicant: Kanzaki Kogyoku Koki Seisakusho Co., Ltd. Agent Person Patent Attorney Toshikazu Yano-1:'(6-

Claims (5)

[Claims] (1) A hydraulic pump P and a hydraulic motor M that drive the axle 13 are mounted on the inner wall of the transmission case that supports the axle 13.
In the configuration in which the bottom wall 1a of the mission case is
In order to erect the pump shaft 4 vertically, a mounting surface 1b for the hydraulic pump is formed, a vertical wall 1i is provided adjacent to the hydraulic pump mounting surface 1b, and the motor shaft 5 is mounted on the vertical wall 1i parallel to the axle 13. , and a motor mounting surface 1j is formed so that the shaft center position is disposed with a discrepancy ΔH from the pump shaft 4 when viewed from above,
An axle drive device characterized in that two oil passages connecting the hydraulic pump P and the hydraulic motor M to each other are formed in the bottom wall 1a and the vertical wall 1i. (2) Two oil passages 1e and 1f on the hydraulic pump side drilled in the bottom wall 1a of the mission case can be opened on the vertical wall side, and each open end can be opened in the direction of the oil passage. The axle drive device according to claim 1, characterized in that check valves 26 and 27 are provided. (3) The check valves 26 and 27 have balls 26a and
27a and valve holders 26b and 27b formed with valve seats 26c and 27c, the valve holders 26b and 2
The axle drive device according to claim 2, characterized in that filters 30 and 31 are disposed so as to fit into the lubricating oil suction holes 26d and 27d formed in the lubricating oil suction holes 7b. (4) The valve holders 26b and 27b on the opposite side of the valve seats 26c and 27c are formed into hollow pipe shapes, and ball pushers 35 and 36 with tapered tips that are slidably guided are installed inside the valve holders 26b and 27b. The tapered portion tips 35a and 36
The lubricating oil suction holes 26d and 27d are formed at the outer peripheral position of a, and an operating rod 37 for integrally operating the ball push rods 35 and 36 is made to protrude outside the transmission case. The axle drive device according to scope 3. (5) Two oil passages 1g and 1h on the hydraulic motor side are bored below the upper end surface of the vertical wall 1i of the transmission case, and two oil passages 1e on the hydraulic pump side in the bottom wall running horizontally.・
1f, and an oil passage 1g, which is bored in the upper end surface of the vertical wall.
1h is covered by a lid body 34 that pivotally supports the pump shaft 4.