JPS63301125A - Hydraulic type speed chance gear - Google Patents

Abstract

PURPOSE:To obtain the compact device in unit form by installing an inner case for accommodating an oil pump, etc., and an outer case for accommodating the inner case and forming a breezer passage under the liquid level of the oil stored in the outer case, into the inner case. CONSTITUTION:An inner case 201 for accommodating an oil pump 27 and an oil motor 29 is installed. An outer case 203 for accommodating an inner case 201 and a reduction gear mechanism is installed. Oil is stored in the outer case 203. In the inner case 201, a breezer passage 207 into which a filter is installed is formed under the oil liquid level 205 of the oil stored in the outer case 203, communicating to the inside of the outer case 203. Therefore, the compact constitution of the hydraulic type speed change gear in unit form can be obtained. Further, between the inner and outer cases 201 and 203, the mixing of foreign material and air into the inner case 201 is prevented, and oil can be introduced and discharged.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a hydraulic transmission.

(Prior Art) A hydraulic transmission including an oil pump and an oil motor is known, for example, from Japanese Utility Model Application No. 60-37654.

In Japanese Utility Model Application Publication No. 60-37654, an oil pump and an oil motor are housed in a single case, and a freezer passage is formed in the case to communicate the inside of the case with the atmosphere.

(Problems to be solved by the invention) However, in order to achieve unitization and compactness,
When attempting to construct a hydraulic transmission by housing an oil pump and an oil motor in an inner case, and providing an outer case housing a reduction mechanism together with the inner case, it was discovered that
In the structure of the freezer passage in Publication No. 654, foreign matter and air in the outer case get mixed into the inner case, which is unfavorable in terms of the durability of the oil pump and oil motor, air entrapment occurs, and cooling in the inner case is also reduced. There is a problem with not being able to do it properly.

The present invention has been devised in view of the above circumstances, and an object of the present invention is to achieve unitization and compactness, further improve the durability of the oil pump and oil motor, and prevent air trapping. The object of the present invention is to provide a hydraulic transmission device that has poor cooling performance.

(Means for Solving the Problems) In order to achieve the above object, the configuration of the present invention includes an inner case 201 that accommodates an oil pump 27 and an oil motor 29, and a deceleration mechanism 31 that accommodates the inner case 201. The outer case 203 stores oil, and the inner case 201 has a freezer passage 207 that communicates with the outer case 203 and has a filter 213 attached thereto. It is characterized by being formed below the liquid level 205 of the stored oil.

(Function) An oil pump 27 and an oil motor 2 are installed inside the inner case 201.
9, and the inner case 201 and the speed reduction mechanism 31 are housed in the outer case 203 to unitize and make the hydraulic transmission 13 more compact.

Between the inside of the inner case 201 and the outer case 203 via a freezer path 207 with a filter 213 , the inner case 201
To allow oil to enter and exit while preventing foreign matter and air from entering. Therefore, the durability of the oil pump 27 and the oil motor 29 can be improved, air can be prevented from being trapped, and the temperature rise inside the inner case 201 can be suppressed.

(Embodiment) A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

Figure 1 is a cutaway plan view of the main parts of a riding lawn mower, Figure 2 is a left side view of the hydraulic transmission, Figure 3 is a cross-sectional exploded view of the same, Figure 4
The figure is a combination of the A-A line arrow view in Figure 3 and the B-B line cross section, and Figure 5 is a combination of the C-C line arrow view in Figure 3 and the D-D line arrow view. Show the diagram.

1 is a riding lawn mower, 3 is a front wheel, 5 is a rear wheel, 7 is a cutter housing, 9 is a seat, 11 is a handle, left and right rear wheels 5
．． A power transmission device 13 is disposed between 5 and 5. The riding lawnmower 1 is equipped with an engine as a power source, and the power of the engine is transferred to the human power shaft 15 of the hydraulic transmission 13 via the belt 17 and the pulley 19. A part of the engine power is transmitted to the hydraulic transmission 13. The engine power is then transmitted to the left and right axles 21.21 to drive the left and right rear wheels 5.5, and part of the engine power is transmitted from the human power shaft 15 to the pulley 23 and belt 25 to the lawn cutter in the cutter housing 7. and rotates the cutter.

The hydraulic transmission 13 includes an oil pump 27 and two oil motors 29 driven by the oil pump 27.
, 29, a reduction mechanism 31° 31 provided between each oil motor 29 and the left and right axles 21, a case 33, etc.
The left and right axles 21°21 are coaxially arranged.

The case 33 includes a board 35 located approximately in the center, a left case 37 fastened to the flat left and right mounting surfaces 35A and 35B of the board 35 with bolts via gaskets 36 and 38, respectively.
It is equipped with a right case 39, etc., and in FIGS. 3 and 4, reference numerals 41 and 43 indicate the bolt attachment portions of the left and right cases 37 and 39.

Mission chambers 45 and 47 are defined on the left and right sides of the substrate 35 by the two cases 37 and 39, respectively, and the left and right mission chambers 45 and 47 are communicated through a through hole formed in the substrate 35. Oil is stored in the mission chambers 45 and 47,
The oil pump 27, oil motors 29, 29, deceleration mechanism 31, and inner end portions of the left and right car fiLIIs 21, 210 are accommodated in the mission chamber 45, 47.

The input $th15 is arranged to extend in the vertical direction via a bracket 49 attached to the outer end of the left case 37, a bearing 51, and an oil seal 53.

The oil pump 27 is disposed on the left mounting surface 35A of the board 35 with its drive shaft 55 parallel to the axle 21, and in Example A, a swash plate type variable displacement axial piston pump is used as the oil pump 27.

The oil pump 27 is a pump case 57 that is attached to the left mounting surface 35A of the board 35 with bolts via a gasket 56.
A drive shaft 55 inserted into the pump case 57 and rotated by engine power, a swash plate 59 attached to the pump case 57 at an angle with respect to the axis of the drive shaft 55, and a spline connection between the drive shaft 55 and A cylinder block 61 that rotates integrally with the mating drive shaft 55, a plurality of pistons 65 that are incorporated in the cylinder block 61 and perform reciprocating motion eight times on the thrust bearing 63 of the swash plate 59, a suction boat 67, and a discharge boat. The valve plate 71 is provided with a valve plate 71 having a number 69 formed therein, and in FIG. 2, 68 is a bearing and 70 is an oil seal.

The swash plate 59 is connected to a speed change operator via a shaft 73, a lever 75, etc., and is configured such that the angle of inclination of the swash plate 59 with respect to the drive shaft 55 can be set to an arbitrary value by operating the speed change operator. In the embodiment, it is possible to switch to three stages: forward, neutral, and reverse.

The left end of the drive shaft 55 is supported by a bearing 77 of the left case 37, and the drive shaft 55 is supported by a bevel gear 79 attached near the left end.
is driven by meshing with the bevel gear 81 of the input shaft 15.

Said drive! The right end of TidI55 is the bearing hole 83 of the board 35
is inserted through and protrudes toward the right mounting surface 35B side of the board 35. In the embodiment, a gear type oil pump (trochoid pump) 85, so-called charge pump 85, which supplies oil to the suction boat 67 of the oil pump 27 is provided in this portion.

The oil pump 85 is the best! 1ith 55, a case 89 that accommodates the gear 87, a suction boat 91, a discharge boat 93, and the like.

The left and right oil motors 29 are mounted on the left and right mounting surfaces 3 of the board 35.
Each output to 5A and 35B! i [h95 car! The oil motor 2 is arranged coaxially in parallel with the llI21, and in the embodiment, the oil motor 2
9, a swash plate type fixed displacement axial piston motor was used.

The oil motor 29 includes a motor case 97, an output shaft 95 disposed within the motor case 97, a swash plate 101 provided on the motor case 97 at an angle with respect to the axis of the output shaft 95, and an output shaft. spline engagement with 95 and output trit
A cylinder block 103 that rotates together with b95, a plurality of pistons 107 that are incorporated in the cylinder block 103 and perform reciprocating motion on the thrust bearing 105 of the swash plate 101, an inlet boat 109 and an outlet boat 111 are formed. A valve plate 113 is provided.

Oil motor 29 attached to left mounting surface 35A of board 35
The case 97A of the oil motor 29 is formed integrally with the case 57 of the oil pump 27, and the case 97B of the oil motor 29 attached to the right mounting surface 35B of the board 35 is formed in a size that covers the gear type oil pump 85. Attach the case 97B to the right mounting surface 35B with bolts through the packing 114,
106 and 108 in Figures 3 and 4 are cases 97A and 97
The bolt attachment part of B is shown.

The cases 97A and 97B define space portions 115 and 117 on the left and right sides of the board 35, respectively, and the rain space portions 115 and 11
7 communicates with each other through a through hole (not shown) formed in the substrate 35, oil is stored in the spaces 115 and 117, and an oil reservoir 119 that bulges downward is provided in the lower part of the case 97B on the right side.
form.

Therefore, in this embodiment, the inner case 2 which houses the oil pump and the oil motor by the cases 97A and 97B and the board 35
01 is configured, and the left and right cases 37, 39 and the board 3
5 constitutes an outer case 203 that accommodates an inner case 201 and a speed reduction mechanism 31.

Then, as shown in FIGS. 2 and 6, the outer case 20
Case 9 below the liquid level 205 of the oil stored in 3.
A pleaser path 207 is provided in the wall of 7A to communicate between the inner and outer cases 201 and 203.

The freezer passage 207 includes a hole 209 penetrating the wall of the case 97A, and a cylindrical holder 21 lightly press-fitted into the hole 209.
1, a filter 213 made of a mesh screen, and a cylindrical cap 215 for attaching the filter 213 to the holder 211.

In addition, as shown in FIGS. 2 and 7, the earthen wall of the left case 37 has a liquid level 2 of the oil stored in the outer case 203.
Freezer path 219 that communicates the space 217 above 05 with the atmosphere
will be established.

The freezer passage 219 has a hole 221 penetrated through the earthen wall of the left case 37, and a cylindrical holder 22 lightly press-fitted into the hole 221.
3, and a cap 2 removably attached to the holder 223.
25, and there is a space 21 above the oil level 205 between the holder 223 and the cap 225, as shown in FIG.
A passage 229 is formed that communicates the air passage 7 with the atmosphere.

The inner end of the output shaft 95 of each oil motor 29 is connected to the base plate 35.
122 in FIG.
4 indicates an oil seal.

Also, each output! T! The outer end of th95 is the left case 37 respectively.
and are supported via bearings 125 by the bearing portion 123 of the right case 39, and a small-diameter reduction gear 12 is provided near the outer end of each output shaft 95.
Install 7.

The left and right axles 21 have their inner ends supported by the bearing holes 121 of the base plate 35, and their inner ends are supported by the left and right outer cases 35, respectively.
37 bearing part 131, bearing 135, oil seal 137
Support through.

The inner end surface 21A of each axle 21 is brought into contact within the bearing hole 129, and the rear @5 is attached to the outer end of each axle 21.

A large-diameter reduction gear 139 that meshes with the reduction gear 127 is attached to a portion of each axle 21 near the cases 37 and 39, and the reduction gears 127 and 139 constitute a reduction mechanism 31 that reduces the speed of the engine.

A brake mechanism 141 for braking the vehicle Ith21 is disposed on the inner side of each of the reduction gears 139.

The brake mechanism 141 includes a case 143 attached to the board 35 and an anchor bin 14 supported by the case 143.
5 and the brake shoe 1 supported by the anchor pin 145
47 and a brake shoe 147 supported by the case 143.
The cam 149 is provided with a cam 149 that expands the joint 1.
51, a rod 153, a joint 155, a rod 157, a lever 159, etc., and are connected to a brake operator.

Next, the oil passages of the oil pumps 27, 85 and the oil motor 29 will be explained.

A suction passage 161 for supplying oil to the suction boat 91 of the gear type oil pump 85 is formed in the base plate 35 so as to open into the oil reservoir 119, and a filter 163 is attached to the opening.

A discharge passage 165 that guides the discharge oil from the discharge boat 93 of the gear type oil pump 85 extends upward at approximately the center in the front-rear direction of the base plate 35, and has a front branch passage 167 whose upper portion extends forward, and a rear branch passage 167 which extends upwardly from the front and back direction of the base plate 35. A relief valve 171 is provided in the discharge passage 165 .

On the other hand, between the inlet boats 109 and 109 of the left and right oil motors 29 and the outlet boats 8111 and 1
11 are communicated with each other by oil passages 173 and 175 extending in the left-right direction, that is, in the thickness direction of the substrate 35.

Also, the suction boat 67 of the oil pump 27 and the oil passage 1
75 communicates with a front oil passage 177 formed in the vertical direction in front of the center of the base plate 35, and the discharge boat 69 of the oil pump 27 and the oil passage 173 are formed in the vertical direction behind the center of the base plate 35. The oil passages 179 communicate with each other.

Then, the upper part of the front oil passage 177 is connected to the front branch passage 167,
The upper part of the rear oil passage 179 is communicated with the rear branch passage 169 via check valves 181 and 183, respectively.

Next, the operation of the hydraulic transmission 13 will be explained.

The drive shaft 55 rotates under the power of the engine, and oil is first supplied to the front oil passage 177 by the gear type oil pump 85 via the suction passage 161, the discharge passage 165, and the front branch passage 167. And when moving forward, drive! a! The rotation of the cylinder block 61 due to the rotation of the tb55 causes each piston 65 to reciprocate, sucking in oil from the front oil passage 177 and suction boat 67, and sucking oil from the discharge boat 69, rear oil passage 179, oil passage 173, and inlet boat 109. The oil is supplied to the motor 29. Then, each piston 107 of the oil motor 29 is reciprocated to rotate the cylinder block 103, and the rotation of the cylinder block 103 rotates the output shaft 95, and the power of the engine is transmitted to the axle 21 via the reduction mechanism 31. The oil then reaches the front oil passage 177 via the outlet boat 111 and the oil passage 175, and is circulated from the front oil passage 177 to the suction boat 67 of the oil pump 27.

Shifting is performed by changing the inclination angle of the swash plate 59 of the oil pump 27, and when in neutral, the swash plate 59 is connected to the base plate 3.
5, the piston 65 does not reciprocate, the check valves 181 and 183 both remain closed, and the oil is returned from the relief valve 171 to the oil reservoir 119.

When traveling backward, the angle of inclination of the swash plate 59 is opposite to that when traveling forward, and the oil supplied from the oil pump 85 flows from the rear branch passage 169 and the rear oil passage 179 to the oil pump 27, contrary to when traveling forward. The oil is sucked into the discharge boat 69, discharged from the suction boat 67, and supplied to the outlet boat 111 of the oil motor 29 through the front oil passage 177 and the oil passage 175. Then, the output shaft 95 is rotated in the opposite direction to the forward movement, and the oil is transferred to the inlet boat 109, the oil passage 173, and the rear oil passage 17.
9 to the discharge boat 69 of the oil pump 27,
Oil pump 85 circulates oil during forward and reverse movement.
This is done while replenishing with oil supplied by.

Furthermore, since the oil flow caused by the oil pump 27 is the sum of the oil flows caused by the left and right oil motors 29, 29, when the direction of the lawn mower 1 is changed, the left and right cars 1J21.2
1 is given the rotation difference.

Therefore, according to this embodiment, the hydraulic transmission 13 is housed, the oil pump 27 and the oil motor 29 are housed in the inner case 201, and the inner case 201 and the speed reduction mechanism 31 are housed in the outer case 203.
Since the hydraulic transmission 13 is configured to accommodate the above, it is possible to unitize the hydraulic transmission 13 and make it compact.

In addition, a freezer passage 207 equipped with a filter 213 connects the inner case 201 and the outer case 203.
Since it is possible to allow oil to flow in and out while preventing foreign matter from entering the inner case 201, the temperature rise within the inner case 201 can be suppressed, and the durability of the oil pump 27 and the oil motor 29 can be improved. Furthermore, since the freezer passage 207 is located below the oil level 205, air does not get mixed into the inner case 201, and air trapping in the oil pump 27 and oil motor 29 can be prevented.

Furthermore, in the embodiment, the oil level 205 inside the outer case 203
Since the freezer passage 219 is provided to communicate the upper space 217 with the atmosphere, the inside of the outer case 203 can be maintained at the atmosphere.
The durability of the hydraulic transmission 13 can be further improved.

In the embodiment, a case has been described in which a gear type oil pump 85 is used, but the hydraulic transmission 13 may be configured without the gear type oil pump 85.

Further, in the embodiment, an axial piston pump is used as the oil pump 27, and an axial piston motor is used as the oil motor 29. However, the types of the oil pump 27 and the oil motor 29 are not limited to those in the embodiment. Alternatively, a variable displacement type may be used for at least one of the oil pump 27 and the oil motor 29.

Further, in the embodiment, a case has been described in which two oil motors 29 are provided corresponding to the left and right axles 21, but the left and right axles 21 may be driven by one oil motor 29.

Further, the structure of the inner case 201 and the outer case 203 is not limited to the structure of the embodiment, and may be constructed arbitrarily, for example, without using the substrate 35.

(Effects of the Invention) As is clear from the above description, according to the present invention, it is possible to achieve unitization and compactness, improve the durability of the oil pump and oil motor, and prevent air trapping.
A hydraulic transmission with excellent cooling performance can be obtained.

[Brief explanation of drawings]

Figure 1 is a cutaway plan view of the main parts of a riding lawn mower, Figure 2 is a left side view of the hydraulic transmission, Figure 3 is a cross-sectional exploded view of the same, Figure 4
The figure is a combination of the A-A line arrow view in Figure 3 and the B-B line cross section, and Figure 5 is a combination of the C-C line arrow view in Figure 3 and the D-D line arrow view. 6 and 7 are sectional views of the freezer path, respectively, and FIG. 8 is a sectional view taken along the line ■--■ in FIG. 7. In the figure, 1 is a riding lawnmower, 3 is a front wheel, 5 is a rear wheel, 11 is a handle, 13 is a hydraulic transmission, 21 is a car mountain, and 27
．． 85 is an oil pump, 29 is an oil motor, 31 is a reduction mechanism, 201 is an inner case, 203 is an outer case, 207
, 219 is Frieza Road. Patent applicant: Agent for Honda Motor Co., Ltd.
Patent Attorney Part 2 1) Part 1 Patent Attorney
Kuni Ohashi Otoma Patent Attorney
Yama Yuyuki Patent Attorney No 1)
Shigeru Figure 2 Figure 6 Figure 8 Procedural amendment (voluntary) January 7, 1986'.

Claims (2)

[Claims] (1) An inner case that accommodates an oil pump and an oil motor, and an outer case that accommodates the inner case and a reduction mechanism; the outer case stores oil, and the inner case contains an outer case. A hydraulic transmission device in which a freezer passage connected to the case and attached with a filter is formed below the surface of the oil stored in the outer case. (2) The hydraulic transmission according to claim 1, wherein the outer case has a freezer passage that communicates the space above the oil level with the atmosphere.