JPH0289868A - Swash plate type hydraulic device - Google Patents

Abstract

PURPOSE:To improve assembly works by providing a rotating member with a control member which controls the installation length of a compression spring so as to prevent synchronizing gears from coming out of meshing when the compression spring is in a condition wherein a shoe member is pressed, and is also in a condition before the spring is housed in a case. CONSTITUTION:Even if these such as a spring holding body 117, a pump shoe 64, a pump swash plate ring 63 and a section 70a are pressed by a spring 118 with pressure at the time of assembly works, these members are concurrently moved to the direction indicated by an arrow head A by a gap L1, the tip end 131a of a cylinder section 131 comes in contact with a cisclip 133 so that the movement is controlled. By this constitution, the meshing of synchronized bevel gears 68a and 68b will never come out. After then, when No.1 section 70a of a motor cylinder 70 is combined with No.2 section 70b with a bolt 110, the tip end 131a of the cylinder section 131 is parted from the cisclip 133 by the gap L1, control in the elongation of the spring 118 by the cisclip 133 is thereby released.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a hydraulic device such as a swash plate type hydraulic pump or a swash plate type hydraulic motor that constitutes a hydraulic continuously variable transmission.

(Prior art) As a publicly known example of such a swash plate type hydraulic system,
There is one disclosed in Japanese Patent No. -76357. In this method, a plurality of plungers are inserted into a cylinder block connected to a rotating shaft in an annular arrangement surrounding the axis of the cylinder block, and an annular shoe is mounted on a swash plate that faces the plurality of plungers and is inclined with respect to the axis of the plungers. is rotatably and slidably disposed, the shoe and the plurality of plungers are connected via a swingable connecting rod, and the shoe and the cylinder block are provided with gears that mesh with each other to press the shoe against the swash plate. It is equipped with a spring.

According to such a configuration, the annular shoe and the cylinder block are rotated in conjunction with each other by the synchronous gear, and the shoe is pressed against the swash plate by the spring, so that lifting and vibration of the shoe are suppressed, and moreover, it is unnecessary for the plunger. It is possible to prevent excessive lateral pressure from being applied.

(Problem to be Solved by the Invention) In devices such as the above-mentioned known example, the spring for pressing the shoe against the swash plate requires a certain amount of spring force when installed to obtain the desired pressing force. Something big is required. In order to obtain a large spring force, it is good to use a disc spring, for example, but a disc spring has a large spring constant, and the spring force changes greatly with changes in the mounting height. For this reason,
It is easily affected by mounting dimensional errors, component dimensional errors, etc., and requires, for example, shim adjustment, resulting in poor assembly performance.

For this reason, it is desirable to use a spring with a small spring constant as the spring. However, although a spring with a small spring constant has a small change in spring force even if the mounting height changes slightly and is less affected by dimensional errors, it requires a longer free length in order to obtain the desired spring force.

For this reason, when assembling the above-mentioned device, there is a problem in that the spring expands greatly and pushes the shoe away from the cylinder block, causing the synchronization gear between the shoe and the cylinder block to disengage. .

If the assembly is performed with the synchronous gears disengaged, there is a risk that the gears will be misaligned when they are assembled into the case and the gears will be engaged again, resulting in incorrect assembly. This has to be done extremely carefully, and there is a problem in that it is difficult to assemble.

SUMMARY OF THE INVENTION In view of these problems, an object of the present invention is to provide a swash plate hydraulic system configured to prevent the synchronous gear from disengaging due to the expansion of the spring during assembly.

(Means for solving the problem) In the present invention, as a means for achieving the above object,
A plurality of plungers are inserted into a cylinder block connected to a rotating shaft in an annular arrangement surrounding the axis of the cylinder block, and a circular plate is placed on a swash plate member that faces the plurality of plungers and has a surface inclined with respect to the axis of the plungers. An annular shoe is arranged to be rotatable and slidable, the shoe and the plurality of plungers are connected via a swingable connecting rod, gears that mesh with each other are provided on the shoe and the cylinder block, and the shoe is connected to the swash plate. A spring for pressing is provided, and a synchronous gear meshes with the rotating shaft, shoe member, and cylinder block, and a compression spring holds the shoe member in a pressed state within the case. When assembling the hydraulic system, when the cylinder block is attached to the rotating shaft, the synchronous gear is engaged, and the compression spring is pressing the shoe member, and before it is held in the case, the compression spring A regulating member is provided on the rotating member to regulate the mounting length of the synchronous gear and prevent the synchronous gear from disengaging.When these are held in the case, the mounting length of the compression spring is regulated by the regulating member. It is shorter than the length, and is configured so that regulation by the regulation member does not work.

(Function) With the above configuration, first, when this device is assembled, the compression spring pushes the shoe and acts to disengage the synchronous wheels, but before this engagement is disengaged, the regulating member is compressed. Since the extension of the spring is restricted, this engagement will not come off. When these are held in the case and the assembly is completed, the regulation of the regulation member does not work,
The shoe is pressed against the swashplate by a compression spring with a desired spring force.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 is a hydraulic circuit diagram of a continuously variable transmission using a swash plate hydraulic pump T (T) to which the present invention is applied. In this figure, the continuously variable transmission T is driven by an ennon E via an input shaft 1. The hydraulic pump P has a constant discharge amount type swash plate axial plunger type hydraulic pump P, and a variable displacement type swash plate axial plunger type hydraulic motor M that drives wheels (not shown) via a forward/reverse switching device 20. These hydraulic pump P and hydraulic motor M have a first oil passage La that communicates the discharge port of the pump P and the suction port of the motor M, and a second oil passage Lb that communicates the suction port of the pump P and the discharge port of the motor M. The two oil passages are connected to form a hydraulic closed circuit.Of these two oil passages La and Lb, the first oil passage La is connected to the pump P driven by the engine E. When the motor M is rotationally driven by hydraulic pressure to drive the wheels, that is, when the wheels are driven by the engine E via the continuously variable transmission T, the pressure becomes high (at this time, the second oil passage Lb is at low pressure). On the other hand, the second oil passage Lb becomes high pressure when the engine brake is applied by receiving driving force from the wheels, such as when the vehicle decelerates (at this time, the first oil passage La has a low pressure ).

A direct coupling clutch valve DC that can connect and disconnect this oil passage La is disposed within the first oil passage La.

A discharge port of a charge pump 10 driven by the engine E via a pair of gear sets 9a and 9b is connected to a charge oil passage Lh having a check valve 15 and a third oil passage Lc having a pair of check valves 3, 3. connected to a closed circuit. Oil sump 1 by charge pump 10
7 and whose pressure is regulated by the charge pressure relief valve 16 is supplied to the lower pressure side of the two oil passages L a + L b by the action of the check valves 3 , 3 .

A governor valve 8 is attached coaxially with this charge pump IO. Hydraulic oil at a predetermined pressure is supplied to this governor valve 8 from a control valve (not shown), and the governor valve 8 converts the pressure of this hydraulic oil into governor oil pressure corresponding to the rotational speed of the engine E. Note that the input and output oil passages connected to the governor valve 8 are not shown in this figure.

A fourth oil passage Ld having a shuttle valve 4 is connected to the closed circuit. This shuttle valve 4 has high pressure and low pressure relief valves 6.7 for oil sump 17.
The fifth and sixth oil passages Le+Lf are connected to each other. The shuttle valve 4 is a 2-point/3-position switching valve, which operates according to the oil pressure difference between the first and second oil passages La+Lb, and switches the oil on the high pressure side of the first and second oil passages La and Lb. The oil passage is communicated with the fifth oil passage Le, and the oil passage on the low pressure side is communicated with the sixth oil passage Lf. As a result, the relief oil pressure in the oil passage on the high pressure side is regulated by the high pressure relief valve 6.
The relief oil pressure in the oil passage on the low pressure side is regulated by a low pressure relief valve 7.

A seventh oil passage Lg that short-circuits both passages is also provided between the first and second oil passages La and Lb, and this seventh oil passage Lg has a variable throttle that controls the opening degree of this oil passage. A main clutch valve CL consisting of a valve is provided.

An output shaft 28 is arranged parallel to the rotating shaft 2 of the hydraulic motor M, and a forward/reverse switching device 20 is provided between both shafts 2 and 28. This device ft20 is rotatably supported by first and second drive gears 21 and 22 arranged on the rotating shaft 2 with an interval in the axial direction, and is meshed with the first drive gear 21. a first driven gear 23, a second driven gear 25 meshing with the second driving gear 22 via an intermediate gear 24 and rotatably supported on the output shaft 28, and first and second driven gears 23.25. A clutch hub 26 is fixed to the output shaft 28 between the clutch hub 26 and a clutch gear 23a or 25a, which is slidable in the axial direction and is formed on the side surfaces of the clutch hub 26 and the driven gears 23 and 25, respectively. A connecting sleeve 27 is provided, and this sleeve 27 is moved left and right by a shift fork 29. The specific structure of this forward/reverse switching device 20 is shown in FIG. In this forward/reverse switching device 20, the sleeve 27 is slid leftward in the figure by the shift fork 29, as shown in the figure (when the clutch gear 23a of the first driven gear 23 and the clutch hub 26 are connected, The output shaft 28 is rotated in the opposite direction to the rotary shaft 2, and the wheels are rotated in the forward direction as the continuously variable transmission T is driven.Meanwhile, the sleeve 27 is slid to the right by the shift fork 29, and the wheels are rotated in the forward direction as the continuously variable transmission T is driven. 25
When the clutch gear 25a and the clutch hub 26 are connected, the output shaft 28 is rotated in the same direction as the rotating shaft 2, and the wheels are rotated in the reverse direction.

Next, the concrete structure of the continuously variable transmission T will be briefly explained using FIG. 2.

This continuously variable transmission T is configured such that a hydraulic pump P and a hydraulic motor M are disposed together in a space surrounded by first to fourth cases 5a to 5d. The input shaft 1 of the hydraulic pump P connects to the output shaft E of the engine E via a coupling 1a.
It is combined with s. A centrifugal filter 50 is disposed on the inner peripheral side of this coupling 1a.

Further, a drive gear 9a is connected to the input shaft 1 by a spline, and a driven gear 9b meshes with the drive gear 9a. The wave gear 9b is coaxially connected to the drive shaft 11 of the charge pump 10, and the rotation of the engine E is transmitted to the drive shaft 11 of the charge pump 10 via the pair of gears 9a and 9b, and the charge pump 10 is driven. be done. This drive shaft 11 passes through the charge pump 10 and protrudes to the side opposite to the gear 9b, and is also connected to the governor valve 8. Therefore, the rotation of the engine E is also transmitted to this governor valve 8, and the governor valve 8 causes the engine E to rotate.
The governor hydraulic pressure corresponding to the rotation of is created.

The hydraulic pump P includes a pump cylinder 60 spline-coupled to the input shaft 1, and a plurality of pump plungers 62 slidably engaged with a plurality of cylinder holes 61 formed in the pump cylinder 60 at equal intervals on the circumference. It is rotationally driven by the power of the engine E transmitted through the input shaft 1.

The hydraulic motor M includes a motor cylinder 70 provided surrounding the pump cylinder 60, and a plurality of motor plungers 72 that slide into a plurality of cylinder holes 71 formed in the motor cylinder 70 at equal intervals on the circumference. It is designed to be able to rotate relative to the pump cylinder 60 coaxially.

The motor cylinder 70 is composed of first to fourth parts 70a to 70d that are aligned in the axial direction and are integrally coupled.

The first portion 70a has a bearing 7 at its left end outer periphery.
The pump swash plate ring 63 is rotatably supported by the case 5b via the pump 9a, and the right inner surface is inclined with respect to the input shaft 1 to form a pump swash plate member. is provided. Second portion 70b
The plurality of cylinder holes 71 are formed in the third portion 70c, and the third portion 70c has a distribution plate 80 in which an oil passage to each cylinder hole 81.71 is formed. The fourth portion 70d includes the first
A gear member GM having second drive gears 21 and 22 is press-fitted and rotatably supported by the case 5c via a bearing 79b.

An annular pump shoe 64 is rotatably and slidably attached to the pump swash plate ring 63, and the pump shoe 84 and the pump plunger 62 are connected to each other via a connecting rod 65 so as to be able to swing freely to some extent. pump shoe 6
4 and the pump cylinder 60 have bevel gears 88 that mesh with each other.
a and 68b are formed. Therefore, when the pump cylinder 60 is rotationally driven from the input shaft 1, the pump shoe 64
The pump plunger 62 is reciprocated in accordance with the inclination of the pump swash plate ring 63 to suck oil from the suction port and discharge oil to the discharge port.

Also, a swash plate member 73 facing each motor plunger 72
The second case 5b is connected to the second case 5b via a pair of trunnion shafts (swing shafts) 73a that protrude from both outer ends in a direction perpendicular to the paper surface.
It is swingably supported by. A motor swash plate ring 73b is disposed on the surface of the swash plate member 73 facing the motor plunger 72, and a motor shoe 74 is attached in sliding contact with the motor swash plate ring 73b.

The motor shoe 74 is swingably connected to the end of each motor brassiere 72. This swash plate member 73 is connected to the link member 3 at a position away from the trunnion shaft 73a.
9, and when the piston rod 33 is moved in the axial direction by the speed changing servo unit 30, the swash plate member 73 swings around the trunnion @73a. It is designed to be moved.

The fourth portion 70d of the motor cylinder 70 is formed hollow, and a fixed shaft 91 fixed to the pressure distribution board 18 is inserted into the center thereof. A distribution ring 92 is fluid-tightly fitted to the left end of the fixed shaft 91, and the left end surface of the distribution ring 92 in the axial direction is eccentric so that it can come into sliding contact with the distribution plate 80.

This distribution ring 92 divides the hollow portion formed in the fourth portion 70d into an inner oil chamber and an outer oil chamber, where the inner oil chamber constitutes the first oil passage La and the outer oil chamber constitutes the first oil chamber. 2 oil passages Lb are configured. Note that the pressure distribution board 18 is connected to the shuttle valve 4.
, high pressure and low pressure relief valves 6.7, etc., are attached to the right side of the third case 5c, and
It is covered by a fourth case 5d.

A pump discharge boat and a pump suction port are bored in the distribution board 80, and the cylinder hole 61 of the pump plunger 62 in the discharge stroke and the inner oil chamber are connected through the discharge boat and the discharge passage connected thereto. 1st oilway La
A second oil passage Lb consisting of the cylinder hole 6e of the pump plunger 62 in the suction stroke and the outer oil chamber is communicated with the pump suction boat and the suction passage connected thereto.
is communicated. Furthermore, a communication path communicating with the cylinder hole (cylinder chamber) 71 of each motor plunger 72 is formed in the distribution panel 80, and the opening of this communication path is formed in the distribution ring 9.
2, the motor cylinder 70 communicates with the first oil passage La or the second oil passage Lb according to the rotation of the motor cylinder 70. Therefore, the cylinder hole 71 of the motor blur 72 in the expansion stroke and the first oil passage La are connected to each other via the communication path, and the cylinder hole 71 of the motor blur 72 and the second oil passage Lb are in the contraction stroke, respectively. communicated.

In this way, a hydraulic closed circuit is formed between the hydraulic pump P and the hydraulic motor M via the distribution m80 and the distribution ring 92. Therefore, when the pump cylinder 60 is driven from the input shaft 1, high-pressure hydraulic oil generated by the discharge stroke of the pump plunger 62 is transferred from the pump discharge boat to the pump discharge passage, the first oil passage La (inner oil chamber), and the like. It flows into the cylinder hole 71 of the motor plunger 72 which is in the expansion stroke through the first communication path which is in the communicating state, and gives thrust to the motor plunger 72 .

On the other hand, the hydraulic oil discharged by the motor plunger 72 in the contraction stroke is transferred to the pump in the suction stroke via the second communication path communicating with the second oil path Lb (outer oil chamber), the pump suction path, and the pump suction port. It flows into the cylinder hole 61 of the plunger 62.

Due to such circulation of hydraulic oil, the pump plunger 82 in the discharge stroke is connected to the motor cylinder 7 via the swash plate ring 63.
The motor cylinder 70 is rotationally driven by the sum of the reaction torque applied to the engine 0 and the reaction torque that the motor plunger 72 receives from the motor swash plate member 73 during the expansion stroke.

The gear ratio of the motor cylinder 70 to the pump cylinder 60 is given by the following equation.

As can be seen from the above equation, if the swash plate member 73 is oscillated by the gear shifting servo unit 30 and the capacity of the hydraulic motor M is changed from O to a certain value, the gear ratio can be changed from 1 (minimum value) to a certain required value. (maximum value).

On the other hand, as described above, the gear member GM serving as the first and second drive gears a is press-fitted and fixed into the fourth portion 70d of the motor cylinder 70. Therefore, the rotational driving force of the motor cylinder 70 is transmitted to the output shaft 28 via the forward/reverse switching device 20. This output shaft 28 is connected to the differential device 10 via final gear sets 28a and 29.
0, and the rotational driving force of the output shaft 28 is transmitted to the differential device 100. Then, the left and right drive shafts 1 are
The rotational driving force divided into 05 and 106 is applied to the left and right wheels (
(not shown) to drive the vehicle.

In addition, a short-circuit path between the first oil passage La and the second oil passage Lb is formed in the fixed shaft 91 inserted into the hollow part of the fourth portion 70d, and this short-circuit path is controlled from fully closed to fully open. A direct coupling clutch valve DC capable of controlling the main clutch valve CL1 and the first oil passage La on and off is provided.

First, the main clutch valve CL will be explained. A short-circuit boat that can communicate the first oil passage La and the second oil passage Lb is bored in the peripheral wall of the fixed shaft 91, and a cylindrical main clutch valve body 95 is installed in the hollow part of the fixed shaft 91. It has been inserted. The valve body 95 is rotatable relative to the fixed shaft 91, and has a short-circuit hole that can be aligned with the short-circuit port. An arm 95a formed at the right end of this valve body 95
By rotating the valve body 95, alignment (overlapping) ffi between the short circuit boat and the short circuit hole can be adjusted. The size of this matching part is the first oil passage La
and the opening degree of the short-circuit passage with the second oil passage Lb, and therefore,
By controlling the rotation of the valve body 95, the opening degree of the short circuit passage can be controlled from fully open to fully closed. If the opening degree of the short-circuit passage is fully open, the hydraulic oil discharged from the pump discharge port to the first oil passage La flows directly from the short-circuit boat and the short-circuit hole into the second oil passage Lb, and also flows into the pump suction port. Therefore, the hydraulic motor M becomes inactive and the clutch OF
The state will be F. Naturally, on the contrary, if the opening degree of the short-circuit passage is fully closed, the clutch ON state is realized.

A direct coupling clutch valve DC is disposed within the hollow portion of this main clutch valve body 95. This direct-coupled Clara valve DC includes a piston shaft 85 that is fitted within the valve body 95 so as to be movable in the axial direction, a shoe 86 that is attached to the tip of the piston shaft 85, and a shoe 86 that is inserted into the piston shaft 85. The pilot spool 84 is composed of a pilot spool 84.
By moving in the axial direction, the piston shaft 85 can be moved in the axial direction to follow this movement. Therefore, the pilot spool 84 is moved to the left, the piston shaft 85 is moved to the left, and the shoe 86 at the tip of the piston shaft 85 is used to block the discharge path of the pump that opens to the end face of the distribution board 80, thereby blocking the first oil path La. is now possible. In this state where the pump discharge passage is closed, the pump plunger 62 is hydraulically locked, and the hydraulic pump P and the hydraulic motor M are directly connected.

Note that this direct connection state is performed at the minimum gear ratio position with the swash plate member 73 of the motor M upright, that is, at the top position. In addition to improving efficiency, the thrust force exerted by the motor plunger 72 on the swash plate member 73 is reduced,
It is possible to reduce frictional resistance and reduce the load applied to bearings and the like.

Next, with reference to FIG. 3, the hydraulic pump P will be explained in more detail. Note that FIG. 3 is a diagram showing a pump unit, which is one of the constituent units of the continuously variable transmission shown in FIG. 2, in an assembled state.

As can be seen from this figure, the motor cylinder 70 constitutes a case of the hydraulic pump P, and the motor cylinder 70
The first to fourth portions 70a to 70d constituting are positioned by fitting or knock pins, and
They are connected together by a plurality of bolts 110 and 111.

The input shaft 1 has a needle bearing 11 on its outer periphery near the left end.
2, and the outer periphery of the right end thereof is supported by the third portion 70a via a needle bearing 113.
c (distribution board 80). The pump cylinder 60 is spline-coupled to the input shaft 1.
is supported at its outer periphery by the second portion 70b via a needle bearing 114.

The annular pump shoe 64, which is rotatably and slidably attached to the pump swash plate ring 63, has its outer peripheral surface supported inside the first portion 70a via a needle bearing 116. Further, a spring holder 117 splined to the input shaft 1 so as to be movable in the axial direction is in spherical contact with the inner circumferential end of the pump shoe 64 , and between the spring holder 117 and the pump cylinder 60 . A spring 118 made of a compression coil spring is tensioned. Therefore, the spring holder 117 uniformly contacts the pump shoe 64 at any position, and the pump shoe 64 is pressed against the pump swash plate ring 63 via the spring holder 117 by the elastic force of the spring 118. This allows pump shoe 6
4 can be rotatably slid on the pump swash plate ring 63 in a constant position.

The connecting rod 65 has ball joints 85a and 85b at its inner and outer ends, and these ball joints 85
a and E35b, it is swingably connected to the pump plunger 62 and the pump shoe 64. Further, the bevel gears 68a and 88b are formed on opposing end surfaces of the pump shoe 64 and the pump cylinder 60, and these bevel gears 68a and 88b are
8a+88b are configured as synchronous gears having the same number of teeth.

By the way, the pressing of the pump shoe 64 against the pump swash plate ring 63 by the spring 118 exerts its function when the predetermined parts are held in the motor cylinder 70 which becomes the pump case and the assembly as a pump unit is completed. be. However, because of this pressing function, when assembling the pump unit, the spring holder 117, the pump shoe 84, the pump swash plate ring 63, and the first portion 70a of the motor cylinder 70 are pressed by the elastic force of the spring 118. , these move in the direction of the arrow.

Therefore, the bevel gear 6 of the pump shoe 64 will not work as it is.
There is a problem in that the pump cylinder 60, which has been correctly synchronized with the bevel gear 68b in advance, comes out of mesh with the bevel gear 68b.

Therefore, in this example, during assembly, the synchronous bevel gear 68a,
A movement regulating structure is provided to prevent 68b from disengaging. That is, in the input shaft 1, an annular groove 132 is formed on the outer periphery of a portion of the first portion 70a of the motor cylinder 70 that protrudes from the cylindrical portion 131.
An outwardly projecting circlip 133 is attached to 32 . When the pump unit is fully assembled, as can be clearly seen from FIG.
There is a gap L1 between the tip 131a and the tip 131a.

However, this gap is set to a size that prevents the synchronous bevel gears 68a and 68b from coming out of mesh.

Therefore, during assembly, the spring holder 1 is
17, pump shoe 84, pump swash plate ring 63, first
Even if the portion 70a is pressed, when these move by a distance L1 in the direction of the arrow A, the tip 131 of the cylindrical portion 131
A is attached to the circlip to restrict its movement.

That is, the expansion of the spring 118 is restricted only by the distance m L s. For this reason, the synchronous bevel gears 68a, 68
B will never come out of engagement.

After this, the first portion 70a of the motor cylinder 70 is
When the cylindrical portion 131 is connected to the portion 70b with the bolt 110, the tip 131a of the cylindrical portion 131 is separated from the circlip 133 by the gap L.
1, and the restriction on the expansion of the spring 118 by the circlip 133 is released. Therefore, the elastic force of the spring 118 acts as a pressing force on the pump shoe 64.

Note that the method of this regulation is not limited to the above method, and may also be configured by a hole formed in the input shaft 1 and a pin fitted into the hole, or by a protrusion formed integrally with the input shaft. .

Furthermore, as shown by the broken line in FIG.
It may also be possible to restrict the expansion of. In addition, regulating member 1
The gap between 35 and the spring holding body 117 is set in the same manner as the above-mentioned gap.

Note that the spring referred to in the present invention has a remarkable effect when a compression coil spring is used, but it goes without saying that the spring is not limited to this. Furthermore, it goes without saying that the present invention is not limited to the swash plate pump of the continuously variable transmission shown in this example.

C1 As described in detail, according to the present invention, the expansion of the spring for pressing the shoe against the swash plate is regulated by a regulating member during assembly, and this regulation is released when assembly is completed. The regulated length is set so that the synchronous gear will not come out of mesh if the spring expands within the regulated range, so the synchronous gear may accidentally come off due to the compression of the spring during assembly. The spring can properly press the shoe upon completion of assembly.

Therefore, incorrect assembly can be prevented during assembly, and assembly efficiency can be improved.

Furthermore, even if the free length of the spring is long, the expansion of the spring is restricted, so a compression spring with a low spring constant can be used. Therefore, even if the installation length of the spring varies slightly due to component installation errors or dimensional errors, the elastic force of the spring does not change much, and there is no need to adjust the installation height, which also makes assembly easier. can be said to improve.

[Brief explanation of the drawing]

Fig. 1 is a hydraulic circuit diagram of a hydraulic continuously variable transmission incorporating a swash plate type hydraulic pump to which the present invention is applied, Fig. 2 is a sectional view of the continuously variable transmission, and Fig. 3 is a pump unit of the hydraulic pump. FIG. 4... Shuttle valve 20... Forward/forward switching device 30... Servo unit for speed change 60... Pump cylinder 81... Cylinder hole 62
... Plunger 63 ... Swash plate ring 64 ...
・Shoe 88a, Et8b...Synchronous bevel gear 70
...Motor cylinder 117...Spring holder P...
・Hydraulic pump M...Hydraulic motor CL...Main clutch valve DC...Direct clutch valve

Claims (1)

[Scope of Claims] 1) A rotating shaft, a cylinder block coupled and disposed on the rotating shaft, and a cylinder block having an axis parallel to the rotating shaft and inserted into the cylinder block in an annular arrangement surrounding the rotating shaft. a swash plate member having a surface facing the ends of the plurality of plungers and inclined with respect to the rotational axis; and a swash plate member disposed rotatably and slidably on the inclined surface of the swash plate member. a connecting rod connecting the shoe and the plurality of plungers; a synchronous gear set provided on the shoe member and the cylinder block and meshing with each other; A swash plate type comprising a compression spring that presses the shoe against the swash plate member, and a case that holds the rotating shaft, the shoe member, and the cylinder block in a state in which the synchronous gear meshes with the shoe member and the compression spring presses the shoe member. In the hydraulic system, when the hydraulic system is assembled, the cylinder block is attached to the rotating shaft, and the synchronous gear meshes with the cylinder block,
When the compression spring is pressing the shoe member and before being held in the case, the rotation shaft A regulating member is provided at the spring, and the mounting length of the compression spring is shorter than the length regulated by the regulating member when held in the case, so that regulation by the regulating member does not work. A swash plate type hydraulic device featuring: