JPH0621656B2 - Swash plate type hydraulic system - Google Patents

Description

Detailed Description of the Invention a. Object of the Invention (Field of Industrial Application) The present invention relates to a hydraulic device such as a swash plate hydraulic pump or a swash plate hydraulic motor that constitutes a hydraulic continuously variable transmission.

(Prior Art) As a publicly known example of such a swash plate type hydraulic device, Japanese Patent Publication No.
There is one disclosed in Japanese Patent Publication No. 76357. This involves inserting and arranging a plurality of plungers in an annular arrangement surrounding the axis of a cylinder block connected to a rotating shaft, and annularly forming a swash plate facing the plurality of plungers and inclined with respect to the axis of the plunger. A shoe is rotatably and slidably arranged, the shoe and the plurality of plungers are connected to each other through a swingable connecting rod, and a gear that meshes with the shoe and the cylinder block is provided to press the shoe against the swash plate. A spring is provided for this purpose.

With such a configuration, the annular shoe and the cylinder block are interlocked with each other by the synchronous gear, and the spring presses the shoe against the swash plate. Therefore, lifting and vibration of the shoe are suppressed, and the plunger is useless. It is possible to prevent a lateral pressure from being applied.

(Problems to be Solved by the Invention) By the way, in the device such as the above-mentioned known example, the spring for pressing the shoe against the swash plate has a large spring force at the time of mounting to obtain a desired pressing force. Is required. In order to obtain a large spring force, for example, a disc spring may be used. However, the disc spring has a large spring constant, and the spring force greatly changes with a change in mounting height. Therefore, it is easily affected by mounting dimension error, component dimension error, etc.
For example, there is a problem that shim adjustment or the like is required and assembly property deteriorates.

Therefore, it is desirable to use a spring having a small spring constant as the spring. However, a spring having a small spring constant has a small change in spring force even if the mounting height slightly fluctuates and is less affected by dimensional error, but has a longer free length in order to obtain a desired spring force. Therefore, when the above-mentioned device is assembled, there is a problem that the spring is greatly extended to push the shoe away from the cylinder block, and the meshing gear of the shoe and the cylinder block is disengaged. .

If the synchronous gears are assembled in such a disengaged state, there is a risk of misalignment when the gears are assembled in the case and the gears are meshed again, causing erroneous assembly. There is a problem that it needs to be carried out very carefully and assembly is poor.

In view of such problems, it is an object of the present invention to provide a swash plate hydraulic device having a structure capable of preventing disengagement of a synchronous gear due to expansion of the spring during assembly.

(Means for Solving the Problems) As means for achieving the above object, in the present invention,
A plurality of plungers are inserted and arranged in an annular array surrounding the axis of a cylinder block connected to a rotary shaft, and a circle is formed on a swash plate member having a surface facing the plurality of plungers and inclined with respect to the axis of the plunger. An annular shoe is rotatably and slidably arranged, the shoe and the plurality of plungers are connected to each other through a swingable connecting rod, and gears that mesh with the shoe and the cylinder block are provided. A spring for pressing is provided, and the rotary shaft, the shoe member, and the cylinder block are held in the case while the synchronous gear meshes with each other and the compression spring presses the shoe member. A restricting member that restricts the axial movement of the shoe member in the disengaged state in a direction in which the rotation-synchronous gear set is disengaged from the compression spring by a predetermined amount or more is released. Is disposed on a rotating shaft, the predetermined amount is set smaller than the axial engagement depth of the rotation synchronization gear set.

(Operation) With the above-described structure, when the holding by the case is released as in the case of assembling and disassembling this device, the compression spring acts in the direction of pushing the shoe member to disengage the rotation synchronizing gear set. However, the restriction member restricts the axial movement of the shoe member by a predetermined amount or more. Here, since the predetermined amount is smaller than the axial engagement depth of the rotary synchronous gear set, the rotary synchronous gear set will not be disengaged even when the holding by the case is released. In the state of being held by the case, the rotation synchronizing gear set is in a normal meshing state, the shoe member is not restricted by the restricting member, and the shoe member is appropriately pressed against the swash plate by the spring force of the compression spring. .

(Examples) Hereinafter, preferred examples of the present invention will be described with reference to the drawings.

FIG. 1 is a hydraulic circuit diagram of a continuously variable transmission having a swash plate hydraulic pump to which the present invention is applied. In this figure, a continuously variable transmission T is driven by an engine E via an input shaft 1. Discharge rate swash plate Axial plunger type hydraulic pump P
And a variable displacement swash plate axial plunger hydraulic motor M that drives wheels (not shown) via the forward / reverse switching device 20. The hydraulic pump P and the hydraulic motor M include a first oil passage La that communicates the discharge port of the pump P and the suction port of the motor M with a second oil passage Lb that communicates the suction port of the pump P and the discharge port of the motor M. These two oil passages form a hydraulic closed circuit and are connected. These two
In the first oil passage La of the book oil passages La and Lb, when the pump P is driven by the engine E and the motor M is rotationally driven by the hydraulic pressure from this pump P to drive the wheels, that is, by the engine E. When the wheels are driven via the continuously variable transmission T, the pressure becomes high (while the second oil passage Lb is at low pressure at this time), while the second oil passage Lb becomes the wheels when decelerating the vehicle. When the engine brake is actuated by receiving the driving force from the engine, the pressure becomes high (at this time, the first oil passage La is at low pressure).

A direct coupling clutch valve DC capable of connecting and disconnecting the oil passage La is arranged in the first oil passage La.

The discharge port of the charge pump 10 driven by the engine E via the pair of gear sets 9a and 9b passes through the charge oil passage Lh having the check valve 15 and the third oil passage Lc having the pair of check valves 3 and 3. Connected to a closed circuit. Oil sump 1 by charge pump 10
The hydraulic oil pumped from 7 and regulated by the charge pressure relief valve 16 is supplied to the low pressure side oil passage of the two oil passages La and Lb by the action of the check valves 3 and 3.

A governor valve 8 is mounted coaxially with the charge pump 10. The governor valve 8 is supplied with hydraulic oil of a predetermined pressure from a control valve (not shown), and the governor valve 8 converts the pressure of this hydraulic oil into governor hydraulic pressure corresponding to the rotational speed of the engine E. It should be noted that the illustration of the input / output oil passages connected to the governor valve 8 is omitted in this figure.

The fourth oil passage Ld having the shuttle valve 4 is connected to the closed circuit. The shuttle valve 4 has high pressure and low pressure relief valves 6 and 7 and is provided with an oil sump 17
The fifth and sixth oil passages Le and Lf connected to the are connected. The shuttle valve 4 is a 2-port 3-position switching valve that operates according to the hydraulic pressure difference between the first and second oil passages La and Lb, and is the high-pressure side oil passage of the first and second oil passages La and Lb. 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 hydraulic pressure of the high pressure side oil passage is regulated by the high pressure relief valve 6,
The relief hydraulic pressure of the low pressure side oil passage is regulated by the low pressure relief valve 7.

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

An output shaft 28 is arranged parallel to the rotary shaft 2 of the hydraulic motor M, and a forward / reverse switching device 20 is provided between the shafts 2 and 28. This device 20 is rotatably supported by the output shaft 28 and first and second drive gears 21 and 22 which are arranged on the rotary shaft 2 with a gap in the axial direction, and the first drive gear 2
1, a first driven gear 23 that meshes with the first driven gear 23, a second driven gear 25 that meshes with the second drive gear 22 via an intermediate gear 24, and is rotatably supported by the output shaft 28, and first and second driven gears. A clutch hub 26 fixed to the output shaft 28 between 23 and 25, and a clutch gear 23a or 25a slidable in the axial direction and formed on the side surfaces of the driven gears 23 and 25, respectively. And a sleeve 27 that is selectively connected, and this sleeve 27 is moved left and right by a shift fork 29. The specific structure of the forward / reverse switching device 20 is shown in FIG. In the forward / reverse switching device 20, when the sleeve 27 is slid to the left in the drawing by the shift fork 29 and the clutch gear 23a of the first driven gear 23 and the clutch hub 26 are connected as shown in the drawing, the output The shaft 28 is rotated in the direction opposite to the rotating shaft 2, and the wheels are rotated in the forward direction as the continuously variable transmission T is driven. On the other hand, in the state where the sleeve 27 is slid to the right by the shift fork 29 and the clutch gear 25a of the second driven gear 25 and the clutch hub 26 are connected, the output shaft 28 is rotated in the same direction as the rotating shaft 2, The wheels are rotated in the reverse direction.

Next, a specific structure of the continuously variable transmission T will be briefly described with reference to FIG.

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

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 driven gear 9b is coaxially coupled 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 to drive the charge pump 10. To be done. The drive shaft 11 penetrates the charge pump 10 and projects to the side opposite to the gear 9 b, and is also connected to the governor valve 8. Therefore, the rotation of the engine E is also transmitted to the governor valve 8, and the governor valve 8 causes the engine E to rotate.
The governor hydraulic pressure corresponding to the rotation of is generated.

The hydraulic pump P has a pump cylinder 60 spline-coupled to the input shaft 1 and a plurality of pump plungers 62 slidably fitted in a plurality of cylinder holes 61 circumferentially equidistantly formed on the pump cylinder 60. And is rotationally driven by the power of the engine E transmitted through the input shaft 1.

The hydraulic motor M is composed of a motor cylinder 70 that is provided so as to surround the pump cylinder 60, and a plurality of motor plungers 72 that are slidably engaged with a plurality of cylinder holes 71 that are formed in the motor cylinder 70 at equal intervals on the circumference. The pump cylinder 60 is concentric with the pump cylinder 60 and is relatively rotatable.

The motor cylinder 70 is composed of first to fourth portions 70a to 70d that are integrally joined side by side in the axial direction.
The first portion 70a has a bearing 9 on the outer periphery of the left end thereof.
While being rotatably supported by the case 5b via a, the right inner surface constitutes an inclined pump swash plate member with respect to the input shaft 1, and a pump swash plate ring 63 is provided on this pump swash plate member. Has been. The plurality of cylinder holes 71 are formed in the second portion 70b, and the third portion 70c is formed.
Has a distribution board 80 in which an oil passage to each cylinder hole 61, 71 is formed. The gear member GM having the first and second drive gears 21 and 22 is press-fitted into the fourth portion 70d, and is rotatably supported by the case 5c via the bearing 9b.

An annular pump shoe 64 is rotatably and slidably mounted on the pump swash plate ring 63, and the pump shoe 64 and the pump plunger 62 are connected to each other via a connecting rod 65 so as to be swingable to some extent. Pump shoe 6
4 and the pump cylinder 60 have bevel gears 68 meshing 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
Are driven to rotate in the same manner, and the pump plunger 62 reciprocates according to the inclination of the pump swash plate ring 63, so that oil is sucked from the suction port and discharged to the discharge port.

In addition, the swash plate member 73 facing each motor plunger 72
However, the second case 5b is provided with a pair of trunnion shafts (swing shafts) 73a protruding from both outer ends thereof in a direction perpendicular to the paper surface.
It is rockably supported by. A motor swash plate ring 73b is arranged on a surface of the swash plate member 73 facing the motor plunger 72, and a motor shoe 74 is attached by sliding on the motor swash plate ring 73b. The motor shoe 74 is swingably connected to the end of each motor plunger 72. The swash plate member 73 is provided at a position apart from the trunnion shaft 73a, and
Piston rod 3 of the servo unit 30 for shifting through
When the piston rod 33 is moved in the axial direction by the shifting servo unit 30, the swash plate member 73 is swung about the trunnion shaft 73a.

The fourth portion 70d of the motor cylinder 70 is formed hollow, and the fixed shaft 91 fixed to the pressure distribution plate 18 is inserted into the central portion of the fourth portion 70d. A distribution ring 92 is liquid-tightly fitted to the left end of the fixed shaft 91, and the axial left end surface of the distribution ring 92 is eccentrically arranged so as to be slidably contactable with the distribution plate 80. With this distribution ring 92, the fourth portion 70d
The hollow portion formed inside is partitioned into an inner oil chamber and an outer oil chamber, the inner oil chamber constitutes a first oil passage La, and the outer oil chamber constitutes a second oil passage Lb. The pressure distribution board 18 has a shuttle valve 4, high-pressure and low-pressure relief valves 6, 7 and the like, is attached to the right side surface of the third case 5c, and is covered by the fourth case 5d.

The distribution board 80 is provided with a pump discharge port and a pump suction port, and is composed of the cylinder hole 61 of the pump plunger 62 in the discharge stroke and the inner oil chamber via the discharge port and the discharge passage connected to this. First oil passage La
And the second oil passage Lb including the cylinder hole 61 of the pump plunger 62 in the suction stroke and the outer oil chamber via the pump suction port and the suction passage connected to the pump suction port.
Are communicated. Further, the distribution board 80 is formed with a communication path communicating with the cylinder hole (cylinder chamber) 71 of each motor plunger 72, and the opening of this communication path is defined by the distribution ring 9.
By the action of 2, the fluid is communicated 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 plunger 72 in the expansion stroke and the first oil passage La communicate with the cylinder hole 71 of the motor plunger 72 in the contraction stroke and the second oil passage LLb via the communication passages. It

In this way, a hydraulic closed circuit is formed between the hydraulic pump P and the hydraulic motor M via the distribution board 80 and the distribution ring 92. Therefore, when the pump cylinder 60 is driven from the input shaft 1, the high-pressure hydraulic oil generated by the discharge stroke of the pump plunger 62 flows from the pump discharge port to the pump discharge passage, the first oil passage La (inner oil chamber), and this. It flows into the cylinder hole 71 of the motor plunger 72 in the expansion stroke through the first communication path in the communicating state and gives a thrust to the motor plunger 72. On the other hand, the hydraulic oil discharged by the motor plunger 72 in the contraction stroke is the pump plunger in the suction stroke via the two communication paths communicating with the second oil passage Lb (outer oil chamber), the pump suction passage, and the pump suction port. 62 into the cylinder hole 61.

Due to such circulation of the hydraulic oil, the pump plunger 62 in the discharge stroke is inserted into the motor cylinder 7 via the swash plate ring 63.
The motor cylinder 70 is rotationally driven by the sum of the reaction torque given to 0 and the reaction torque received by the motor plunger 72 in the expansion stroke from the motor swash plate member 73.

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 formula, if the swash plate member 73 is swung by the shifting servo unit 30 and the capacity of the hydraulic motor M is changed from 0 to a certain value, the gear ratio is from 1 (minimum value) to a required value (the minimum value). Maximum value).

On the other hand, as described above, the gear member GM having the first and second drive gears is press-fitted and fixed to 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. The output shaft 28 is connected to the differential device 10 via the final gear sets 28a and 29.
The rotational drive force of the output shaft 28 is transmitted to the differential device 100. Then, the rotational driving force divided by the differential device 100 into the left and right drive shafts 105, 106 is transmitted to the left and right wheels (not shown) to drive the vehicle.

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

First, the main clutch valve CL will be described. A short-circuit port that allows the first oil passage La and the second oil passage Lb to communicate with each other is formed in the peripheral wall of the fixed shaft 91, and a cylindrical main clutch valve body 95 is provided in the hollow portion of the fixed shaft 91. Has been inserted. The valve body 95 is rotatable relative to the fixed shaft 91 and has a short-circuit hole which can be aligned with the short-circuit port. An arm 95a formed at the right end of the valve body 95
By rotating the valve, the valve body 95 can be rotated to adjust the amount of matching (overlap) between the short-circuit port and the short-circuit hole. The size of this matching portion becomes the opening degree of the short-circuit passage between the first oil passage La and the second oil passage Lb. Therefore, the opening degree of the short-circuit passage is fully opened to fully closed by the rotation control of the valve body 95. Can be controlled up to. When 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 directly flows into the second oil passage Lb from the short-circuit port and the short-circuit hole and also flows into the pump suction port. Therefore, the hydraulic motor M is deactivated and the latch is turned off. Of course, conversely, when the opening degree of the short-circuit passage is fully closed, the clutch ON state is realized.

A direct coupling clutch valve DC is arranged in the hollow portion of the main clutch valve body 95. The direct coupling clutch DC includes a piston shaft 85 inserted axially movably into the valve body 95, a shoe 86 attached to the tip of the piston shaft 85, and a pilot inserted into the piston shaft 85. The spool 84 and the pilot spool 84
Is moved in the axial direction, the piston shaft 85 can be moved in the axial direction so as to follow it. 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 spool 85 closes the discharge passage of the pump opening to the end face of the distribution board 80 and shuts off the first oil passage La. You can do it. In the state where the pump discharge passage is closed as described above, 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 where the swash plate member 73 of the motor M is upright, that is, at the top position, and by direct connection, power transmission from the input shaft 1 to the output shaft 2 is performed. While improving efficiency, the thrust exerted on the swash plate member 73 by the motor plunger 72 is reduced,
It is possible to reduce the frictional resistance and the load applied to the bearing and the like.

Next, the hydraulic pump P will be described in more detail with reference to FIG. 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 the case of the hydraulic pump P, and the motor cylinder 70
The first to fourth portions 70a to 70d constituting the above are positioned by fitting or knock pins, and
The bolts 110 and 111 are integrally connected.

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

The annular pump shoe 64 rotatably and slidably mounted on the pump swash plate ring 63 has an outer peripheral surface supported inside the first portion 70 a via a needle bearing 116. A spring holder 117, which is spline-coupled to the input shaft 1 so as to be movable in the axial direction, is in spherical contact with the inner peripheral end portion of the pump shoe 64, and between the spring holder 117 and the pump cylinder 60. A spring 118, which is a compression coil spring, is stretched. 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 by the elastic force of the spring 118 via the spring holder 117. As a result, the pump shoe 64 can always rotate and slide on the pump swash plate ring 63 at a fixed position.

The connecting rod 65 has inner and outer end ball joints 65a and 65b.
The pump plunger 62 and the pump shoe 64 are swingably connected by a and 65b. The bevel gears 68a and 68b are formed on the end faces of the pump shoe 64 and the pump cylinder 60 facing each other.
Reference characters a and 68b are 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 components are held in the motor cylinder 70 serving as the pump case and the assembly of the pump unit is completed. is there. However, because of its pressing function, the spring holder 117, the pump shoe 64, 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 when the pump unit is assembled. , These move in the direction of arrow A. For this reason, if it is left as it is, there is a problem that the bevel gear 68a of the pump shoe 64 and the bevel gear 68b of the pump cylinder 60 that are correctly synchronized in advance are disengaged from each other.

Therefore, in this example, the synchronous bevel gear 68a,
A movement restricting structure is provided for preventing disengagement of 68b. That is, in the input shaft 1, the annular groove 132 is formed on the outer periphery of the portion of the first portion 70 a of the motor cylinder 70 that projects from the cylindrical portion 131.
A circlip 133 that protrudes outward and is used as a restricting member is attached to 2. In the assembled state of the pump unit, as can be seen clearly from FIG. 3, the gap L ₁ is formed between the circlip 133 and the tip 131a of the cylindrical portion 131.
have. However, this gap L ₁ is equal to the synchronous bevel gear 68.
The dimensions are set so that the meshing of a and 68b is not disengaged.

Therefore, at the time of assembly, the spring 118 holds the spring holder 1 by the spring 118.
17, pump shoe 64, pump swash plate ring 63, first
Even if the portion 70a of the cylindrical portion 131a is pressed, when these portions move like the direction of the arrow A by the distance L ₁ , the tip 131 of the cylindrical portion 131
a is attached to the circlip, and its movement is restricted.
That is, the expansion of the spring 118 is restricted only by the distance L ₁ . Therefore, the synchronous bevel gears 68a and 68b are not disengaged from each other.

Then, the first portion 70a of the motor cylinder 70 is moved to the second
When the bolts 110 are connected to the portion 70b of FIG.
Only _{one is} separated, and the expansion restriction of the spring 118 by the circlip 133 is released. Therefore, the elastic force of the spring 118 acts as a pressing force of the pump shoe 64.

The regulation method is not limited to the above, and may be configured by a hole formed in the input shaft 1 and a cotter pin fitted therein, or may be configured by a projection integrally formed on the input shaft. .

Further, as shown by a broken line in FIG. 3, a regulating member 135 made of a circlip is provided substantially in the center of the input shaft 1, and the tip of a spring holder 117 is abutted against the regulating member 135, so that the spring 118
May be restricted. The restriction unit 13
5 and the spring holder 117 have the same gap as the gap L ₁ .

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 present invention is not limited to this. It is also needless to say that the present invention is not limited to the swash plate pump of the continuously variable transmission shown in this example.

C. EFFECTS OF THE INVENTION As described above, according to the present invention, the axial movement of the shoe member in the direction in which the compression spring is disengaged from the rotation synchronizing gear set in the state where the holding by the case is released is regulated by a predetermined amount or more. The regulating member is installed on the rotary shaft, and this predetermined amount is set to be smaller than the axial meshing depth of the rotary synchronous gear set, so that it can be held by the case as when assembling and disassembling this device. In the released state, the compression spring acts on the shoe member in the direction to disengage the rotation synchronizing gear set, but the regulation member regulates the axial movement of the shoe member by a predetermined amount or more. Since the predetermined amount is smaller than the axial meshing depth of the rotation synchronous gear set, even if the holding by the case is released,
The meshing of the rotation synchronizing gear set will not be disengaged. In the state of being held by the case, the rotation synchronizing gear set is in a normal meshing state, the shoe member is not restricted by the restricting member, and the shoe member is appropriately pressed against the swash plate by the spring force of the compression spring. .

Moreover, even if the free length of the spring is long, the expansion of the spring is restricted, so that a compression spring having a low spring constant can be used. Therefore, even if the spring mounting length varies to some extent due to component mounting errors, dimensional errors, etc., the elastic force of the spring does not change much and the mounting height does not need to be adjusted. It can be said to improve.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of a hydraulic continuously variable transmission having a swash plate 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. It is a sectional view taken out and shown. 4 ... Shuttle valve, 20 ... Forward / reverse switching device 30 ... Shifting servo unit 60 ... Pump cylinder, 61 ... Cylinder hole 62 ... Plunger, 63 ... Swash plate ring 64 ... Shoes, 68a, 68b ...... Synchronous bevel gear 70 ...... Motor cylinder 117 ...... Spring holder 133, 135 ...... Circlip (regulating member) P ...... Hydraulic pump, M ...... Hydraulic motor CL ...... Main clutch valve DC ...... Direct coupling clutch valve

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-63-150475 (JP, A) JP-A-62-218663 (JP, A) JP-A-57-68569 (JP, A) Actual development Sho-62- 26571 (JP, U) Actually developed 50-4305 (JP, U)

Claims (1)

[Claims] 1. A rotary shaft, a cylinder block connected to the rotary shaft, and a shaft parallel to the rotary shaft. The cylinder block is inserted and arranged in an annular array surrounding the rotary shaft. A plurality of plungers, a swash plate member facing the end portions of the plurality of plungers and having a surface inclined with respect to the rotation axis, and swash plate members rotatably and slidably disposed on the inclined surface of the swash plate member. An annular shoe member, a connecting rod connecting the shoe member and the plurality of plungers, a synchronous gear set provided on the shoe member and the cylinder block and meshing with each other, and the shoe member supported by the rotating shaft. And a compression spring for pressing the swash plate member with the rotary shaft, the shoe member, and the cylinder block are engaged with each other by the synchronous rotary gear set, and A swash plate type hydraulic device including a case for holding the member in a pressed state, wherein the shoe member is located in a direction in which the rotation synchronizing gear set is disengaged by the compression spring when the holding by the case is solved. A swash plate type hydraulic device characterized in that a regulating member for regulating the axial movement of a fixed amount or more is arranged on the rotary shaft, and the predetermined amount is set to be smaller than the axial meshing depth of the rotary synchronous gear set. apparatus.