JP2704866B2 - Variable displacement swash plate hydraulic system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swash plate type hydraulic device applied to a hydraulic pump or a hydraulic motor, and more particularly to a plurality of cylinders which are rotatable about a rotation axis and are annularly arranged around the rotation axis. A cylinder having a hole, a plurality of plungers fitted in the cylinder hole, a swash plate for bringing the front surface into contact with the outer ends of the plungers, and supporting the back surface of the swash plate via bearings to rotate the plunger. The present invention relates to an improvement of a variable displacement type swash plate type hydraulic device including a swash plate holder arranged to be tiltable around a trunnion axis perpendicular to the axis and a fixed swash plate anchor supporting the swash plate holder.

[0002]

2. Description of the Related Art Conventionally, in such a hydraulic apparatus, opposed surfaces of a swash plate holder and a swash plate anchor are formed as cylindrical surfaces centering on the trunnion axis, and both ends of the swash plate holder are arranged on the trunnion axis. It is known that a swash plate anchor is provided with a rotatably supported trunnion shaft, and a transmission lever operated by a transmission control device is serration-coupled to an outer end of the trunnion shaft (for example, Japanese Patent Application Laid-Open No. Sho 61-61). 15305
No. 7).

[0003]

SUMMARY OF THE INVENTION In a conventional hydraulic device,
There is a drawback in that a side pressure is generated between the swash plate holder and the swash plate anchor due to the unbalanced load acting on the swash plate from each plunger, and the rotational resistance of the swash plate holder is increased. Further, since it is necessary to attach the transmission lever to the trunnion shaft, the trunnion shaft must be formed long, and as a result, there is a disadvantage that the device becomes large in the trunnion shaft direction. Further trunnion shaft
Is formed in a simple columnar shape.
Reduce the load on the load by reducing the contact surface pressure of the engaging portion with the
The trunnion shaft itself has a relatively large diameter
In that case, the shaft and its surroundings are bulky,
There is also a drawback of increasing the size.

[0004] It is an object of the present invention to provide a swash plate type hydraulic apparatus in which all such disadvantages are eliminated.

[0005]

In order to achieve the above object, the present invention provides a swash plate holder and a swash plate anchor which face each other.
Formed on a spherical surface centered on the intersection of the cylinder rotation axis and the trunnion axis , and the trunnion
A half extending on the axis and facing the outer peripheral arc surface to the swash plate anchor side
With a cylindrical trunnion shaft protruding,
The semi-cylindrical recess that rotatably engages the shaft
Formed in, the swash plate holder, the peripheral portion in which it separates away from the trunnion axis, the first, characterized in that the concatenation of the shift control device for tilting the swash plate holder.

[0006] The present invention, in addition to the above features, the phosphorus <br/> da, the swash plate, and integrally connected an output shaft extending through the swash plate holder and swashplate anchor, the swash plate anchor A second feature is that it is connected to the output shaft via a bearing so as not to move in the axial direction, and is connected to the casing so as not to rotate.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on embodiments of the present invention shown in the accompanying drawings.

First, in FIG. 1, a power unit U for a motorcycle includes an engine E and a hydrostatic continuously variable transmission T, and a crankshaft 1 and a continuously variable transmission T of the engine E share a common casing 4. It is accommodated in and supported.

The continuously variable transmission T has an input cylinder shaft 5 rotatably supported on a middle wall of a casing 4 via a ball bearing 6 and an output shaft 31 surrounded by the input cylinder shaft 5. And are arranged in parallel. Crankshaft 1 is 1
The input cylinder shaft 5 is driven via the secondary transmission R ₁ and the primary torque damper D ₁ , and the output shaft 31 is connected to the rear wheel of the motorcycle via the secondary transmission R ₂ , the secondary torque damper D ₂ and the propeller shaft 3. (Not shown).

In FIG. 2 and FIG. 3, the continuously variable transmission T
Is composed of a constant displacement type swash plate type hydraulic pump P and a variable displacement type swash plate type hydraulic motor M, and the present invention is applied to the swash plate type hydraulic motor M.

The hydraulic pump P is provided on the inner peripheral wall of the input cylinder shaft 5 via a ball bearing 11 so as to be rotatable relative to each other, and is provided on the pump cylinder 7 so as to surround the rotation axis. A large number of pump plungers 9, 9 which are respectively slid into a large number and an odd number of cylinder holes 8, 8 in an annular arrangement, and a pump swash plate 10 whose front surface is in contact with the outer ends of these pump plungers 9, 9 ... The pump swash plate 10 is provided with an angular contact bearing so as to hold the pump swash plate 10 at a fixed angle with respect to the axis of the pump cylinder 7 around a virtual trunnion axis O ₁ orthogonal to the axis of the pump cylinder 7. It is rotatably supported by a pump swash plate holder 5 a formed integrally with the input cylinder shaft 5 via the radial ball bearing 12 and 12.

At this time, the inner raceway groove 12i of the angular contact bearing 12 is provided on the back surface of the pump swash plate 10,
Further, the inner raceway grooves 13i of the radial ball bearing 13 are formed on the outer peripheral surface thereof, and thus the pump swash plate 10 is configured as a common inner race body of the bearings 12 and 13. On the other hand, the outer race grooves 12o and 13o of both bearings 12 and 13 are formed on outer race bodies 35 and 36 that are individually fitted in the pump swash plate holder 5a. When the angular contact bearing 12 receives an axial load from the pump swash plate 10, it cooperates with the inner and outer raceway grooves 12i and 12o to give the pump swash plate 10 a centering action.

When the input cylinder shaft 5 rotates, the pump swash plate 10 can reciprocate the pump plungers 9, 9,... To repeat the suction and discharge strokes.

On the other hand, the hydraulic motor M is provided with a pump cylinder 7
Motor cylinder 17 arranged coaxially to the left
And a large number of odd-numbered cylinder holes 1 in an annular arrangement provided around the rotation axis of the motor cylinder 17.
., Which are respectively slid onto the motor plungers 19, 19,.
, A motor swash plate holder 22 for supporting the motor swash plate 20 via an angular contact bearing 14 and a radial ball bearing 15, and a motor swash plate holder 22. And a motor swash plate anchor 23 that supports the rear surface of
The motor swash plate anchor 23 guides the tilt of the motor swash plate holder 22 around a trunnion axis O ₂ orthogonal to the axis of the motor cylinder 17.

At this time, the inner raceway groove 14i of the angular contact bearing 14 is provided on the back of the motor swash plate 20,
The inner raceway grooves 15i of the radial ball bearing 15 are formed on the outer peripheral surface, and the motor swash plate 20 is formed as a common inner race body of the bearings 14 and 15. On the other hand, the outer raceway groove 14o of the angular contact bearing 14 is formed on the motor swash plate holder 20, and the outer raceway groove 15o of the radial ball bearing 15 is formed on the outer race 37 fitted on the motor swash plate holder 22. When the angular contact bearing 14 receives an axial load from the motor swash plate 20, it cooperates with the inner and outer raceway grooves 14i and 14o to give the motor swash plate 20 a centering action.

In the hydraulic motor M, the cylinder hole 18 and the motor plunger 19 are formed to have a larger diameter than that of the hydraulic pump P so that the maximum capacity is larger than that of the hydraulic pump P.

As shown in FIG. 4, the opposing surfaces f ₁ and f ₂ of the motor swash plate holder 22 and the motor swash plate anchor 23 that come into contact with each other are centered on the intersection of the axis of the motor cylinder 17 and the trunnion axis O _2. Is formed on the spherical surface.

Further, the motor swash plate holder 22, the peripheral edge portion close to the trunnion axis O ₂ is, <br/> with its outer peripheral arcuate surface and disposed on said axis O ₂ side motor swash plate anchor 23 A pair of semi-cylindrical trunnion shafts 22a, 22a protrude integrally, and are rotatably engaged with a pair of semi-cylindrical recesses 23a, 23a formed at both ends of the motor swash plate anchor 23. Furthermore, the motor swash plate holder 22, the peripheral portion that is far away from the trunnion axis O ₂ is said axis O ₂
A short connection arm 25 extending in a direction perpendicular to the direction is integrally protruded, and a transmission control device 27 for controlling the inclination angle of the motor swash plate 20 is connected to this.

Referring again to FIGS. 2 and 3, the angular contact bearing 14 is configured to co-operate with the motor swash plate holder 22 to provide centering action to the motor swash plate 20.

The motor swash plate anchor 23 is fixed to the left side wall of the casing 4 with bolts 21 together with a cylindrical cylinder holder 24 connected to the right end thereof (see FIG. 1). The cylinder holder 24 rotatably supports the outer peripheral surface of the motor cylinder 17 via a ball bearing 26.

The motor swash plate 20 is moved by rotation of the motor swash plate holder 22 between an upright position perpendicular to the axis of the motor cylinder 17 and a maximum inclined position inclined at a certain angle. In the inclined state, the motor plunger 19,
19 can be reciprocated to repeat the expansion and contraction strokes.

Pump cylinder 7 and motor cylinder 17
Are integrally connected to each other to form a cylinder block B, and an output shaft 31 passes through the center of the cylinder block B. Then, a flange 31a formed on the outer periphery of the output shaft 31 abuts against the outer end of the motor cylinder 17, and the outer end of the pump cylinder 7 abuts against a stopper ring 28 locked on the outer periphery. Cylinder block B
The cylinder block B is fixed to the output shaft 31 by spline fitting the motor shaft 17 (in the illustrated example) to the output shaft 31.

The right end of the output shaft 31 penetrates through the pump swash plate 10 and extends to the outside of the input cylinder shaft 5.
0, it is rotatably supported by the input cylinder shaft 5 via the angular contact bearing 29.

The left end of the output shaft 31 extends through the motor swash plate 20, the motor swash plate holder 22, and the motor swash plate anchor 23, and is rotatable by the motor swash plate anchor 23 via the angular contact bearing 30. It is supported.

In this way, in the continuously variable transmission T, the components from the input cylinder shaft 5 to the output shaft 31 are assembled into one assembly, and the input cylinder shaft 5 and the output shaft 31 are connected to each other at the right end. respectively to the input member of the output member and the second torque damper D ₂ of the primary torque damper D ₁ is spline-coupled.

In order to rotate the pump swash plate 10 synchronously with the pump cylinder 7, the pump swash plate 10 is formed with a spherical recess 10a with which the corresponding spherical end 9a of the pump plunger 9 engages.

The motor swash plate 20 is connected to the motor cylinder 1
7, the motor swash plate 20 includes:
A spherical recess 20a is formed in which the spherical end 19a of the corresponding motor plunger 19 engages.

Each of the spherical concave portions 10a and 20a is formed with a radius larger than the radius of the corresponding spherical end portions 9a and 19a, and the engagement state with the spherical end portions 9a and 19a is set at any position. It has been secured.

2, 3 and 5, a cylinder block B has cylinder holes 8, 8,.
An annular inner oil passage 52 and an outer oil passage 53 concentrically arranged around the output shaft 31, and both oil passages 52, 53 between the group and the cylinder holes 18, 18,...
, And the same number of first valve holes 54, 54, and second valve holes 55, 55, respectively, as the cylinder holes 8, 8, ..., 18, 18, ... penetrating radially through the annular partition wall and the outer peripheral wall of the outer oil passage 53.
And the adjacent cylinder holes 8, 8... And the first valve holes 54, 54
Are connected to each other, and a number of motor ports b are connected to each other to connect adjacent cylinder holes 18, 18 and the second valve holes 55, 55 to each other.

The inner oil passage 52 is provided in the cylinder block B
Is formed as an annular groove on the inner peripheral surface of the output shaft 31, and the open surface thereof is closed by the outer peripheral surface of the output shaft 31.

The first valve holes 54, 54 are provided with spool-type first distribution valves 61, 61, respectively.
55 also have spool-type second distribution valves 62, 62 ...
Are rubbed with each other. Then, the first distribution valves 61, 61
Are provided on the outer end of the second eccentric ring 63 surrounding the outer ends of the second distribution valves 62, 62.
4 are respectively engaged via ball bearings 65 and 66, and the first distribution valve 6 is used to force their engagement.
The outer end portions of the first eccentric ring 63 are concentric with the first eccentric ring 63.
The second distribution valve 6 is connected to each other by a forcing wheel 67.
Are connected to each other by a second forcing wheel 68 which is concentric with the second eccentric wheels 62, 62.

The first eccentric wheel 63 is integrally connected to the inner end of the input cylinder shaft 5 and, as shown in FIG.
It is arranged at a position eccentric by a predetermined distance ε ₁ from the center of the output shaft 31 along ₁ .

When relative rotation occurs between the input cylinder shaft 5 and the pump cylinder 7, each of the first distribution valves 61 causes the first eccentric wheel 63 to double the eccentric amount ε ₁ in the first valve hole 54. The pump cylinder 7 is reciprocated between a radially inner position and a radially outer position of the pump cylinder 7 as a stroke. Then, as shown in FIG. 5, in the discharge region D of the hydraulic pump P, the first distribution valve 61 moves on the inner position side to communicate the corresponding pump port a with the outer oil passage 53 and the inner oil passage. The hydraulic fluid is disconnected from the passage 52, the hydraulic oil is pressure-fed from the cylinder hole 8 to the outer oil passage 53 by the pump plunger 9 during the discharge stroke, and in the suction area S, the first distribution valve 61 moves toward the outer position. The corresponding pump port a is communicated with the inner oil passage 52 and is disconnected from the outer oil passage 53, and the hydraulic oil is sucked into the cylinder hole 8 from the inner oil passage 52 by the pump plunger 9 during the suction stroke.

The second eccentric wheel 64 is mounted on the cylinder holder 24 with the output shaft 3 as shown in FIGS.
It is connected via a pivot 32 parallel to 1 to be able to swing between three positions of a clutch on position n, a clutch off position f and a lockup position l. And the second eccentric wheel 64
In the clutch-on position n, than the amount of eccentricity epsilon ₂ from the center of the central predetermined distance epsilon ₂ occupies an eccentric position (Fig. 6) The clutch-off position f the output shaft 31 of the output shaft 31 along the trunnion axis O ₂ Also occupy a position with a large distance ε ₃ eccentric (FIG. 7). The lock-up position 1 occupies a concentric position with the output shaft 31 (FIG. 8).

The second eccentric wheel 64 integrally has an outwardly projecting lug 33 on the peripheral wall opposite to the pivot 32, and the eccentric wheel for controlling the second eccentric wheel 64 to the three positions. The wheel control device 34 is connected. The eccentric wheel control device 34 will be described later.

When the second eccentric wheel 64 is shifted to the clutch-on position n as shown in FIG. 6 while the motor cylinder 17 is rotating, each of the second distribution valves 62 is moved by the second eccentric wheel 64. , it is reciprocated between the radially inner position and outer position of the motor cylinder 17 to twice the eccentric distance epsilon ₂ as stroke in the second valve hole 55. Then, in the expansion region Ex of the hydraulic motor M, the second distribution valve 62 moves on the inside position side to connect the corresponding motor port b to the outside oil passage 53 and to block the inside oil passage 52, and High-pressure hydraulic oil is supplied from the oil passage 53 to the cylinder hole 18 of the motor plunger 19 during the expansion stroke, and the contraction region S
h, the second distribution valve 62 moves on the outer position side,
The corresponding motor port “b” communicates with the inner oil passage 52 and is disconnected from the outer oil passage 53, and hydraulic oil is discharged from the cylinder hole 18 of the motor plunger 19 to the inner oil passage 52 during the contraction stroke.

When the second eccentric wheel 64 is shifted to the clutch off position f as shown in FIG. 7, each of the second distribution valves 62
The eccentric amount ε in the second valve hole 55 by the second eccentric wheel 64
Motor cylinder 17 with stroke twice as long as ₃
Is reciprocated between an inner position and an outer position in the radial direction. In the inner and outer positions, the second distribution valve 62
Is opened to the outside of the cylinder block B.

When the second eccentric wheel 64 is shifted to the lock-up position 1 as shown in FIG. 8, all the second distribution valves 62,
62 simultaneously close the corresponding motor ports b.

In the above configuration, when the input cylinder shaft 5 of the hydraulic pump P is rotationally driven by the engine E while the second eccentric wheel 64 is held at the clutch-on position n, the pump swash plate 1
0 alternately gives the pump plungers 9, 9... The discharge and suction strokes.

The pump plunger 9 has a discharge area D
While the hydraulic oil is pumped from the cylinder hole 8 to the outer oil passage 53, and the inner oil passage 52
The working oil is sucked into the cylinder hole 8 from above.

The high-pressure hydraulic oil sent to the outer oil passage 53 is
While being supplied to the cylinder hole 18 of the motor plunger 19 located in the expansion region Ex of the hydraulic motor M, the contraction region Sh
Of the cylinder bore 1 by the motor plunger 19
Hydraulic oil is discharged from 8 to the inner oil passage 52.

In the meantime, the reaction torque received by the pump cylinder 7 from the pump swash plate 10 via the pump plunger 9 in the discharge stroke, and the reaction torque received by the motor cylinder 17 from the motor swash plate 20 via the motor plunger 19 in the expansion stroke. , The cylinder block B is rotated, and the rotation torque is transmitted from the output shaft 31 to the secondary reduction gear 3.

In this case, the output shaft 31 with respect to the input cylinder shaft 5
Is given by the following equation.

[0044]

(Equation 1)

Therefore, if the capacity of the hydraulic motor M is changed from the maximum value to zero, the gear ratio is changed from the maximum value (low state) to one.
(Top state). In addition, since the capacity of the hydraulic motor M is determined by the stroke of the motor plunger 19, the gear ratio can be steplessly controlled from the maximum value to 1 by tilting the motor swash plate 20 from the inclined position to the upright position. it can.

During operation of the transmission T, the pump swash plate 10 receives a thrust load in the opposite direction from the pump plungers 9, 9... And the motor swash plate 20 receives a thrust load in the opposite direction from the motor plungers 19, 19. while the plate 10 is subjected to
The thrust load in the right direction in FIGS. 2 and 3 is applied to one end of the output shaft 31 via the angular contact bearing 12, the input cylinder shaft 5 and the angular contact bearing 29.
(Right end in FIGS. 2 and 3) and the motor swash plate 20
The thrust load in the other direction (left direction in FIGS. 2 and 3) is applied to the other end of the output shaft 31 via the angular contact bearing 14, the motor swash plate holder 22, the motor swash plate anchor 23, and the angular contact bearing 30 ( Figure
It is supported on the left end at a few points. Therefore, output shaft 3
Thrust load of the two directions applied to both ends of 1, and cause tensile stress to the output shaft 31 to the shaft 31 itself
The shoulder of the motor swash plate anchor 23 abuts on the casing 4 supporting the shaft 31 because it is only received.
The swash plate anchor 2
3 is output via the angular contact bearing 30
The other end of the shaft 31 is supported without play in the axial direction.
In this case, when the swash plate anchor 23 acting on the motor
Last load, angular contact bearing 30
It is received by the other end portion of the output shaft 31 via the shaft, and does not act on the casing 4.

In this case, the motor swash plate holder 22 and the motor swash plate anchor 23 face the spherical surfaces f ₁ and f ₂ centered on the intersection of the axis of the motor cylinder 17 and the trunnion axis O _2. The motor swash plate holder 22 exhibits a centering function by the interaction of the spherical surfaces. As a result, by the shift control device 27 to push and pull the connecting arm 25, the motor swash plate holder 22 is smoothly rotated in the trunnion axis O ₂ around obtained, to easily control the inclination angle of the motor swash plate 20 be able to. Moreover, by the engagement of the recess 23a of the trunnion shaft 22a and the motor swash plate anchor 23 of the motor swash plate holder 22, the motor swash plate holder 22, acting blindly except tilt around the trunnion axis O ₂ is prevented.

Further, the connecting arm 25 connected to the transmission control device 27 is connected to the trunnion axis O ₂ of the motor swash plate holder 22.
Since it is protruded from the peripheral portion far away from the vehicle, there is no need to attach a speed change lever to the trunnion shaft 22a.
And can be formed short trunnion shaft 22a, it is possible to reduce the size of the trunnion axis O ₂ direction of the hydraulic motor M, the number of parts can be deleted.

In the hydraulic pump P and the hydraulic motor M, the swash plates 10 and 20 are centered from the front and rear by the angular contact bearings 12 and 14, and the outer circumference is supported by radial ball bearings 13 and 15. Therefore, in any inclined state, a predetermined position on the rotation axis of the cylinder block B, that is, the trunnion axis O ₁ , O ₂
Accurately held in position.

Therefore, the spherical ends 9a, 19a of the plungers 9, 19 always engage normally with the spherical recesses 9a, 19a of the corresponding swash plates 10, 20, so that the plungers 9, 19 correspond to the corresponding oblique plates 9. The side thrust received from the plates 10 and 20 is reliably reduced, and the increase in the sliding resistance of each of the plungers 9 and 19 can be suppressed. In addition, each swash plate 10,
Synchronous rotation of the cylinder block B and the cylinder block B can prevent wear of the contact portions between the plungers 9 and 19 and the corresponding swash plates 10 and 20. Further, it is not necessary to apply a large axial load by a conventional spring to the corresponding angular contact bearings 12 and 14 for holding the respective swash plates 10 and 20 at the predetermined positions. It is possible to reduce the load on the load 12 and 14 and increase the durability.

Next, when the second eccentric wheel 64 is shifted to the clutch off position f, the high pressure outside oil passage 53 is opened to the outside of the cylinder block B by the second distribution valve 62. Is no longer supplied, and power transmission from the hydraulic pump P to the hydraulic motor M is shut off. That is, a so-called clutch off state is obtained.

When the motor swash plate 20 is upright, that is, when the top state is obtained, the second eccentric wheel 64 is shifted to the lock-up position 1 so that all the second distribution valves 64 are simultaneously connected to the corresponding motor port b. , The hydraulic motor M is insulated from the high-pressure outer oil passage 53 and the low-pressure inner oil passage 52, and leakage of hydraulic pressure from the hydraulic motor M is reduced. Further, since the outer oil passage 53 is insulated from the hydraulic motor M, the outer oil passage 5
Thus, the volume of the high-pressure system including 3 is reduced, and the incompressibility of the high-pressure system hydraulic oil is improved even if air bubbles are mixed in the hydraulic oil to some extent. As described above, the transmission efficiency in the top state is improved.

Next, a mechanism for supplying hydraulic oil to the inner and outer oil passages 52 and 53 will be described with reference to FIGS.

At the left end wall of the casing 4 opposed to the left end of the output shaft 31, two inner and outer oil guide pipes 40, 41 or support plates 42, 43 are attached, respectively. Is inserted into the left end of the output shaft 31 in a relatively rotatable and oil-tight manner. On the left end wall of the casing 4, a supply oil passage 45 that guides oil discharged from the supply pump 44 to the outer oil guide pipe 41 and a return oil that guides oil discharged from the inner oil guide pipe 40 to the oil reservoir 46. A road 47 is provided. An oil cooler 48 is interposed in the return oil passage 47.

A pair of first and second valve cylinders 50 ₁ , 50 ₂ parallel to the axis of the output shaft 31 are bridged on both end walls of a cylindrical valve chamber 49 formed at the left end of the output shaft 31. A low-pressure oil passage 56 and a high-pressure oil passage 57 that communicate with the first and second valve cylinders 50 ₁ and 50 ₂ , respectively, are formed in the output shaft 31.

As shown in FIGS. 2 and 3, the low-pressure oil passage 56 is connected to the inner oil passage 52 through a lateral hole 58.
The high-pressure oil passage 57 is connected to the outer oil passage 53 through a horizontal hole 59, an annular oil passage 60, and a slant hole 69.

Returning to FIG. 9 to FIG. 11, the first and second valve cylinders 50 ₁ and 50 ₂ have small chambers 72 ₁ and 72 _{2 in} which the first and second check valves 71 ₁ and 71 ₂ are accommodated in the middle respectively. Having. Valve hole 73 ₁ in these chambers 72 _1, 72 ₂ of the left end wall is opened and closed by the corresponding check valves 71 _1, 71 _2, 7
3 ₂ are bored, these valve holes 73 _1, 73 _2,
Continuous with the short pipe 74 _1, 74 ₂ projecting from the left wall of the valve chamber 49, also two short pipes 74 _1, 74 ₂ holes 82 _1, 82 ₂
Communicates with the outer oil guide pipe 41 via the

In the normal operation state of the continuously variable transmission T, the first and second check valves are controlled by the pressures of the inner and outer oil passages 52 and 53, ie, the low pressure and the high pressure oil passages 56 and 57. 71
_1, 71 ₂ are to close the valve hole 73 _1, 73 ₂ prevents backflow of hydraulic fluid from the low and high pressure oil passage 56 and 57 to the short pipe 74 _1, 74 _2, between the hydraulic pump P and hydraulic motor M of the low pressure oil passage 56 or the high pressure oil passage 57 by the oil leakage from the hydraulic closed circuit becomes lower than the discharge pressure of the supply pump 44, the first check valve 71 ₁ or the second check valve 71 ₂ is opened, the supply pump 44 discharge oil is supplied through a short tube 74 ₁ or 74 ₂ to the low pressure oil passage 56 or the high pressure oil passage 57.

The valve chamber 49 has _two valve cylinders 50 ₁ , 50 _2.
A clutch valve 76 having a pair of sliding holes 75 ₁ and 75 ₂ that fits on the outer peripheral surface of the clutch is accommodated. Each valve cylinder 50 ₁ , 50 ₂
The outer peripheral surface of the stepped portion 77 ₁ of the intermediate, 77 left side half-section diameter ₂ as a border, right half portion has become a large diameter sliding hole 75 ₁ in correspondence with this, 75 ₂ of the inner peripheral As for the surface, the left half is a small diameter,
The right half has a large diameter. Each sliding hole 75 ₁ , 75 ₂
Each valve cylinder 50 in the middle portion of the _1, 50 ₂ of the stepped portions 77 _1, 77
₂ is pressure-receiving chamber 78 _1, 78 ₂ of the ring facing is formed, these pressure receiving chamber 78 _1, 78 ₂ is the low and high pressure oil passage 56,
57 is always in communication with each other.

The clutch valve 76 can move between a clutch-on position in contact with the right end wall of the valve chamber 49 and a clutch-off position in contact with the left end wall. Valve cylinders 50 ₁ , 50 ₂ to communicate with chamber 49
First valve holes 79 ₁ and 79 ₂ provided in the pressure receiving chamber 7
8 ₁ , 78 ₂ and valve sleeves 50 ₁ , 50 ₂ and short pipes 74 ₁ , 74
₂ to communicate with the relief oil chambers 81 ₁ and 81 ₂ between
0 _1, 50 second valve hole 80 ₁ is provided in _two, 80 ₂ are opened and closed by the clutch valve 76. That is, first, the second valve hole 79 _1, 79 _2; 80 _1, 80 ₂ are both closed at the clutch-on position of the clutch valve 76 is adapted to be opened in the clutch off position.

The relief oil chambers 81 ₁ and 81 ₂ are provided with two-forked through holes 8.
The valve chamber 49 communicates with the outer oil guide pipe 41 through two through holes 84.

On the left end wall of the valve chamber 49, a pair of operating rods 85, 85 penetrating therethrough are slidably supported. These operating rods 85, 85 are opposed to a pair of flanges 76a, 76a formed at the right end of the clutch valve 76, between which a first pressure adjusting spring 86 and a second pressure adjusting spring 87 surrounding the first pressure adjusting spring 86 are arranged. Will be arranged. The first pressure adjusting spring 86 is set to be always operated so as to always urge the clutch valve 76 in the direction of the clutch-on position, while the second pressure adjusting spring 87 is operated by operating rods 85 and 8.
The free length is set so as not to operate until 5 moves rightward from the left movement limit by a predetermined distance. Therefore, as shown in FIG. 17, the total set load of the two pressure adjusting springs 86 and 87 shows a two-step change characteristic with the rightward movement of the operating rod 85, and the latter half has a steep gradient.

An operating ring 89 slidably supported by a guide cylinder 88 projecting from the support plate 43 is connected to the outer ends of the operating rods 85, 85 via a release bearing 90. The operation ring 89 is operated by a clutch control device 91 described later.

When the continuously variable transmission T is cruising or accelerating, the outer oil passage 53, ie, the high-pressure oil passage 57, has a high pressure. During the deceleration operation, the inner oil passage 52, ie, the low-pressure oil passage 56, has a high pressure. High pressure always acts on _one of the pressure receiving chambers 78 ₁ and 78 ₂ of the valve 76. By the way, the clutch valve 76
Since the aforementioned difference in diameter is given to the front and rear portions of the sliding holes 75 ₁ , 75 ₂ , the pressure receiving chambers 78 ₁ , 78 2 are provided.
The pressure receiving surface of the left end wall ₂ is larger than that of the right end wall. As a result, a thrust is applied to the clutch valve 76 to the left, that is, in the clutch off direction by the high pressure. If this thrust is greater than the pressing force to the right, that is, the clutch-on direction, by the first pressure adjusting spring 86 or the first and second pressure adjusting springs 86, 87, the clutch valve 76 maintains the clutch-on position, If so, it moves toward the clutch off position.

At the clutch-on position of the clutch valve 76, the first and second valve holes 79 ₁ , 79 ₂ ; 80 ₁ , 8
0 Since ₂ is closed, low and high pressure oil passage 56 and 57
Prevents short-circuiting and communication with the relief oil chambers 81 ₁ and 81 ₂ , but when the clutch valve 76 moves toward the clutch off position, the first and second valve holes 79 ₁ , 79 ₂ ; 8
0 ₁ and 802 are opened, and the _two oil passages 56 and
Short-circuit of the hydraulic pressure between the hydraulic pumps 57 and leakage of the hydraulic pressure from the oil passages 56 and 57 to the relief oil chambers 81 ₁ and 81 ₂ occur, and the power transmission between the hydraulic pump P and the hydraulic motor M is reduced or cut off.

Therefore, in a state where the operating ring 89 is shifted in the clutch-on direction and the maximum set load is applied to the pressure regulating springs 86 and 87, if an excessive forward load or reverse load is applied to the continuously variable transmission T, , High pressure oil passage 57 or low pressure oil passage 56
The clutch valve 76 is displaced in the clutch off direction due to the excessive hydraulic pressure generated in the above, and the hydraulic pressure is released, so that the transmission of the excessive load can be reduced.

When the operating ring 89 is shifted in the clutch off direction to allow the second pressure adjusting spring 87 to play and the set load of the first pressure adjusting spring 86 to be minimized, the high pressure oil passage 57
Alternatively, the clutch can be immediately displaced in the clutch off direction by the hydraulic pressure of the low pressure oil passage 56 to obtain the clutch off state. Further, if the intermediate position of the operating ring 89 is adjusted while the second pressure adjusting spring 87 is allowed to play, the half-clutch state can be finely adjusted.

As described above, by adjusting the set load of the pressure adjusting springs 86 and 87 by the displacement of the operating ring 89, the clutch valve 76 is adjusted.
Therefore, even if the viscosity of the hydraulic oil changes due to the temperature change, stable clutch control can be always performed by operating the operating ring 89.

Incidentally, if the pressure regulating spring is formed in an unequal pitch type, even a single spring can obtain the same spring characteristics as described above.

In FIGS. 3 and 10, the output shaft 31 has:
Further, two lubricating oil passages 93 and 9 directly opening to the valve chamber 49 are provided.
The two oil passages 93 are connected to one lubricating oil passage 94 on the downstream side. These oil passages 93, 94 communicate with a lubrication portion around the output shaft 31 through a plurality of orifices 95, 95,. Therefore, during operation of the continuously variable transmission T, a part of the oil sent from the replenishing pump 44 to the outer oil guide pipe 41 is also distributed to the lubricating oil passages 93 and 94 via the valve chamber 49, and furthermore, a plurality of orifices 95. , 95 ... and supplied to each lubrication unit. At this time, the amount of oil supplied to the lubricating portion is limited by the orifice 95, so that the supply of hydraulic oil from the outer oil guide pipe 41 to the low-pressure oil passage 56 or the high-pressure oil passage 57 is not hindered.

Next, the transmission control device 27, the eccentric wheel control device 34, and the clutch control device 91 will be described with reference to FIG.

First, the operation starts with the shift control device 27.

The connecting arm 25 of the motor swash plate holder 22 is connected to a piston rod 101a of a speed change piston 101 via a link 100. The speed change piston 101 is accommodated in a hydraulic cylinder 102 fixed to the casing 4, and when the hydraulic cylinder 102 moves rightward, the motor swash plate 20 is tilted to the low side via the swash plate holder 22. The motor swash plate 20 can be raised up to the top side.

The inside of the hydraulic cylinder 102 is divided into a first working chamber 103 ₁ on the left side and a second working chamber 103 ₂ on the right side by the shifting piston 101, and these working chambers 103 ₁ , 1
03 ₂ shift valve 104 is connected to.

The transmission valve 104 includes a cylindrical valve box 105 fixed to the casing 4 and a pair of left and right outer spool valves 106 ₁ , slidably housed in the valve box 105.
106 ₂ and these outer spool valves 106 ₁ , 106 ₂
A pair of left and right inner spool valves 107 ₁ , 107 ₂ which are slidably fitted inside and penetrate both end walls of the valve box 105.
When an outer spring 108 for biasing the right outer spool valve 106 ₂ to the left, is composed of two inner spool valves 107 _1, 107 ₂ inner spring 109 for urging the separating direction, inside the outer spring 108 A set load greater than the spring 109 is applied.

The valve box 105 is provided with the first and second working chambers 1.
03 _1, 103 and having ₂ to it that the first and second output ports 110 ₁ that communicates, 110 ₂ on one side, a pair of left and right input ports 111 _1, 111 _2, a pair of right and left control port 112 _1, 112 ₂ And a pair of left and right discharge ports 1
13 ₁ and 113 ₂ are provided on the other side.

The output ports of the hydraulic pump 114 are connected to the input ports 111 ₁ and 111 ₂ , and the control ports 112 ₁ and 111 ₂ are connected to each other.
The 112 _second discharge port of the supply pump 44 is connected via a first solenoid valve 115 _1. Also, discharge port 11
The discharge port of the replenishing pump 44 is connected to 3 ₁ and 113 ₂ via a second solenoid valve 115 ₂ , while the third solenoid valve 115 2
_It communicates with the oil reservoir 46 via ₃ .

[0078] The first inlet solenoid valve 115 _first orifice 116 ₁ is provided, the orifice 116 diameter of the orifice 116 ₂ than ₁ is provided in the second inlet solenoid valve 115 _2.

The supply pump 44 sucks oil from the oil reservoir 46, and the hydraulic pump 114 sucks oil discharged from the supply pump 44. The discharge pressure of the replenishing pump 44 is controlled by the first relief valve 11
The 7 _1, replenishment and the hydraulic oil to the continuously variable transmission T, among the outer spool valve 107 _1, 107 _2; 106 _1, 106 ₂
And the like, for example, 12 kg / cm ^2, and the discharge pressure of the hydraulic pump 114 is adjusted to the second relief valve 1
Pressure suitable for the operation of such shift piston 101 by 17 _2, is adjusted for example to 35 kg / cm ^2.

The supply pump 44 and the hydraulic pump 114
As shown in FIG. 1, the engine E is connected to an end of a crankshaft 1 and driven simultaneously from the shaft 1.

The first to third solenoid valves 115 _{1 to} 115 ₃
Are normally open type, and are controlled as shown in the following table when shifting.

[0082]

[Table 1]

[0083] In Thus, in the state of the above table I, acts on the right end surface discharge pressure of the right outer spool valve 106 ₂ via the first solenoid valve ₁₁₅₁ of the supply pump 44 as shown in FIG. 13, also the also it acts on the right end surface of the right inner spool valve 107 ₂ through the orifice 118 _{and second} valve 106 _2. As a result, the right outer and inner spool valves 106 ₂ and 107 ₂ move to the left until they abut against the left outer and inner spool valves 106 ₁ and 107 ₂ , respectively, and communicate between the first input and output ports 111 ₁ and 110 _1. And the second output port 102 _{2 is connected} to the oil sump 4
Since communicating to 6, the discharge pressure of the hydraulic pump 114 is introduced into the first working chamber 103 ₁ of the oil chamber cylinder 102, the shift piston 101 receives the hydraulic pressure is shifted rightward, tilting the motor swash plate 20 to the low side Let me do it.

Also, when the shifting piston 101 is moving rightward,
When the state of II, as shown in FIG. 14, the hydraulic pressure acting on the right end surface of the right inner spool valve 107 ₂ is released to the oil reservoir 46 through the leakage orifice 119 ₂ of the valve, the inner spring 109 with it the right inner spool valve 107 ₂ by the repulsive force moved to the right, stops when the leakage orifice 119 ₂ is closed by the right outer spool valve 106 _2. Thus, the right inner spool valve 106 ₂ cuts off the communication between the second working chamber 103 ₂ of the hydraulic cylinder 102 and the oil reservoir 46, so that the speed change piston 101 can be stopped halfway to the right.

Next, when the state shown in the above Table III is established, as shown in FIG.
Acts on the left end face of the left outside spool valve 106 ₁ through ₂ ,
Also acting on the left end surface of the left inner spool valves 107 ₁ via the orifice 118 ₁ of the valve 106 _1. As a result, the left outer and inner spool valves 106 ₁ , 107 ₁ move to the right limit together with the right outer and inner spool valves 106 ₂ , 107 ₂ to communicate between the second input / output ports 111 ₂ , 110 ₂ and since communicates the first output port 110 ₁ to the oil reservoir 46, the discharge pressure of the hydraulic pump 114 is introduced into the second actuation chamber 103 ₂ of the hydraulic cylinder 102, the shift piston 101 receives the hydraulic pressure is shifted leftward, Motor swash plate 20
To the top side.

[0086] During operation of the continuously variable transmission T, the first to third electric system of the solenoid valve 115 _{1-115 3} fails, these solenoid valves are all cut off the energization, and opens (upward Table IV). In this case, as shown in FIG. 16, the discharge pressure of the replenishment pump 44 is increased by the first and second solenoid valves 115 ₁ , 115 ₁ .
115 but passes through both of the _2, because the orifice 116 of the _second solenoid valve 115 ₂ inlet is narrowed than the orifice 116 of the _first solenoid valve 115 ₁ inlet orifice 1
The hydraulic pressure passing through 16 ₁ is applied to the right outer and inner spool valves 10.
6 ₂ , 107 ₂ are pressed against the right end face.
The hydraulic pressure passing through the 6 ₂ is released to the oil reservoir 44 immediately third through the solenoid valve 115 _3. As a result, the right outer and inner spool valves 106 ₂ , 107 ₂ move to the left limit together with the left outer and inner spool valves 106 ₁ , 106 ₂ , and the first
ON, it causes communication between the output port 111 _1, 110 _1, since the communication between the second output port 110 ₂ to the oil reservoir 46, the discharge pressure of the hydraulic pump 114 is introduced into the first working chamber 103 ₁ of the hydraulic cylinder 102 Then, the shift piston 101 is moved to the right to tilt the motor swash plate 20 to the low side. Therefore, it is possible to prevent the vehicle from being unable to start even when the electric system fails.

[0087] If the operation of the engine E is stopped, also the operation of the supply pump 44 and the hydraulic pump 114 is stopped, the first through third solenoid valves 115 _{1-115 3} becomes open every state, the shift valve 104 Figure The state becomes 12. That is, the first
And the second output ports 110 ₁ and 110 ₂ are closed by the inner spool valves 107 ₁ and 107 ₂ , respectively.
The speed change piston 101 remains at the current position.

Next, the eccentric wheel control device 34 will be described.

In FIG. 12, the device 34 includes an apparatus main body 120 fixed to the casing 4 and the apparatus main body 12.
A cylinder 122 fitted in the cylinder hole 121 and capable of sliding by a predetermined stroke, and a piston 123 fitted in the cylinder 122 and capable of sliding by a predetermined stroke are provided, and protrude from the right end face of the piston 123. The tip of the piston rod 123a is the lug 33 of the second eccentric ring 64.
Linked to

The sliding stroke of the cylinder 122 is regulated by the left end face and the right end face of the cylinder 122 abutting against stopper walls 124 and 125 fixed to the apparatus main body 120, respectively. Further, the sliding stroke of the piston 123 is regulated by the left end surface and the right end surface of the piston 123 contacting the end walls 126 and 127 fixed to the cylinder 122, respectively. Then, when the cylinder 122 is held at the right limit and the piston 123 is operated to the left limit, the second eccentric wheel 64 can be controlled to the clutch-on position n, and the cylinder 122 remains at the right limit. When the piston 123 is operated to the rightmost limit, the second eccentric wheel 64 can be controlled to the lockup position l. When both the cylinder 122 and the piston 123 are operated to the leftmost position, the second eccentric wheel 64 can be controlled. Can be controlled to the clutch off position f.

The cylinder 122 is urged rightward by a return spring 128, and the piston 123 is urged leftward by a return spring 129 in the cylinder 122.

An operating arm 130 for operating the cylinder 122 is fixed to one end of the cylinder 122, and the operating arm 130 is connected to a manual clutch operating device or an automatic clutch operating device (not shown).

[0093] within the cylinder 121 is partitioned into a second chamber 131 ₂ of the first working chamber 131 ₁ and the right side of the left by the piston 123, the first leading to the chambers 131 _1, 131 ₂
And second ports 132 ₁ and 132 ₂ are formed in one side wall of the cylinder 122.

The apparatus main body 120 is provided with a pair of left and right first and second inlet ports 133 ₁ and 133 ₂ and a pair of left and right first and second outlet ports 134 ₁ and 134 _2. In the limit position, the first and second ports 13
2 ₁ and 132 ₂ are the first and second inlet ports 132 ₁ and 1
32 ₂ and each communicating, at leftward movement limit position of the cylinder 122 so that the ₂ first and second ports 132 _1, 132 respectively communicating with the first and second outlet ports 134 _1, 134 _2.

[0095] The first inlet port 133 ₁ always communicates with the discharge port of the supply pump 44, while the second inlet port 133 _2, which communicates with the discharge port of the supply pump 44 via the fourth solenoid valve 115 _4, the It communicates with the oil sump 46 via the five solenoid valve 115 ₅ . Also, the first and second outlet ports 134 ₁ , 13
4 ₂ communicates with the oil reservoir 46.

[0096] In Thus, closing the fourth solenoid valve 115 ₄ as shown in FIG. 12 while holding the cylinder 122 to the rightward movement limit, opening the fifth solenoid valve 115 _5, the discharge pressure of the supply pump 44 is It is introduced into the second actuation chamber 131 _2, the first working chamber 13
Since 1 ₁ oil is discharged to the oil reservoir 46, the piston 123
Moves left to move the second eccentric wheel 64 to the clutch-on position n.
To control.

[0097] By operating until moved to the left limit of the cylinder 122 by operating arm 130 from this state, the piston 123 follow actuated cylinder 122 by the second Hidaridoshitsu 131 ₂ introduced hydraulic from the supply pump 44, the second eccentric wheel 64 to the clutch off position f.

With the cylinder 122 held at the rightmost limit, the fourth solenoid valve 115 ₄ is opened and the fifth solenoid valve 115 ₅ is opened.
Is closed, the discharge pressure of the replenishing pump 44 is introduced into the first and second working chambers 131 ₁ and 131 ₂ and presses both end faces of the piston 123. The left end face of the piston 123 is larger than the right end face. The piston 123 moves to the right by the hydraulic pressure acting on the pressure receiving area difference because the sectional area of the rod 123a is wider than the sectional integral, and controls the second eccentric wheel 64 to the lock-up position l.

Finally, the clutch control device 91 will be described. The device 91 includes a hydraulic cylinder 140 fixed to the casing 4 and a piston 141 fitted in the hydraulic cylinder 140 and capable of sliding a predetermined stroke, and a piston protruding from a left end surface of the piston 141. A fork member 142 for operating the operating ring 89 is fixed to the rod 141a. The rightward movement of the piston 141 increases the set load of the pressure regulating springs 86, 87.

[0100] Hydraulic cylinder 140 in the second working chamber by the piston 141 of the first operating chamber 143 ₁ and the right side of the left 14
3 ₂ and is partitioned into, these first, second working chamber 143 _1,
First and second ports 144 ₁ , 144 connected to 143 _2
2 is drilled in one side wall of the hydraulic cylinder 140. The first port 144 ₁ communicates with the discharge port of the supply pump 44,
The second port 144 ₂ communicates with the discharge port of the supply pump 44 via the sixth solenoid valve 115 ₆ , while the seventh solenoid valve 115 2
_Also communicates with the oil reservoir 46 via ₇ .

As shown in FIG. 12, the sixth solenoid valve 1
Opens the 15 _6, by closing the seventh solenoid valve 115 _7,
When the discharge pressure of the replenishment pump 44 is reduced to both working chambers 143 ₁ and 143 ₂
And acts on both end surfaces of the piston 141, but the left end surface of the piston 141 is larger than the right end surface of the piston rod 1.
41a, the piston 141 moves rightward due to the hydraulic pressure acting on the area difference between them, and the pressure adjusting spring 8
Increase the set load of 6,87.

[0102] Also contrary to the above, when opening the seventh solenoid valve 115 ₇ closes the sixth solenoid valve 115 _6, the discharge pressure of the supply pump 44 is introduced only into the first operating chamber 143 _1, the second working chamber since 143 ₂ are opened to the oil reservoir 46, the piston 141 is moved to the right, reducing the set load of the pressure regulating spring 86 and 87.

[0103]

As described above, according to the first aspect of the present invention, the opposing surfaces of the swash plate holder and the swash plate anchor are formed as a spherical surface centered on the intersection of the cylinder rotation axis and the trunnion axis. The swash plate holder is connected to a shift control device for tilting the swash plate holder at a peripheral portion of the swash plate holder which is far away from the trunnion axis. Thus, it is possible to prevent a lateral pressure from being generated between the swash plate holder and the swash plate anchor, and to easily control the capacity of the hydraulic device by always rotating the swash plate holder lightly. In addition, since the speed change control device is connected to the peripheral portion of the swash plate holder, a speed change lever is not required, so that the device can be made compact in the trunnion axial direction and the number of parts can be reduced at the same time.

[0104] In particular , a trunnion is provided around the periphery of the swash plate holder.
With the outer circumferential surface facing the swash plate anchor side.
While projecting semi cylindrical trunnion axis, so to form a semi-cylindrical recess for rotatably engaged the trunnion shaft to the swash plate anchor, by the engagement of the trunnions shaft and the recess, the swash plate holder Can be prevented other than tilting around the trunnion axis, and the swash plate holder and the swash plate anchor can be assembled extremely easily .
The contact surface pressure of the engaging portion between the trunnion shaft and the recess
Increase the effective radius of the trunnion shaft itself to reduce
Even if the shaft and the concave portion are each formed in a semi-cylindrical shape,
And its peripheral part is effectively increased in the radial direction of the shaft.
The engagement portion by the reduction of the surface pressure
The improvement of the durability and the miniaturization of the equipment.
You.

[0105] Further according to the second aspect of the present invention, the sheet re <br/> Sunda, swash plate, an output shaft extending through the swash plate holder and swashplate anchor is integrally connected, the swash plate anchor Since this output shaft is connected to the output shaft via a bearing so as not to be movable in the axial direction, and is connected to the casing so as not to rotate, all the thrust load exerted on the swash plate from the group of plungers can be borne between the cylinder and the output shaft. Thus, the casing can be released from the thrust load, and its thickness can be reduced, and furthermore, its weight and size can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a power unit for a motorcycle including a hydrostatic continuously variable transmission according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the continuously variable transmission.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is an exploded perspective view of a main part of the continuously variable transmission.

FIG. 5 is a sectional view taken along line VV of FIG. 3;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 3;

FIG. 7 is an operation explanatory view corresponding to FIG. 6;

FIG. 8 is an operation explanatory view corresponding to FIG. 6;

FIG. 9 is an enlarged view of an IX part in FIG. 2;

FIG. 10 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is a sectional view taken along line XI-XI of FIG. 9;

FIG. 12 is a longitudinal sectional view of a shift control device, an eccentric wheel control device, and a clutch control device of the continuously variable transmission.

FIG. 13 is an explanatory diagram of an operation of a shift valve in the shift control device.

FIG. 14 is an explanatory diagram of an operation of a shift valve in the shift control device.

FIG. 15 is an explanatory diagram of an operation of a shift valve in the shift control device.

FIG. 16 is an explanatory diagram of an operation of a shift valve in the shift control device.

FIG. 17 is a characteristic diagram of a pressure adjusting spring.

[Explanation of symbols]

f ₁ , f ₂ spherical surface M hydraulic motor 14 as a hydraulic device 14 bearing 17 motor cylinder 18 as a cylinder 18 cylinder hole 19 motor plunger 20 as a plunger 20 motor swash plate as a swash plate 22 motor swash plate holder as a swash plate holder 22a trunnion Shaft 23 motor swash plate anchor as swash plate anchor 23a recess 27 speed change control device 30 bearing 31 output shaft

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Tadashi Tsunoda, 1-4-1 Chuo, Wako-shi, Saitama Prefecture Inside of Honda R & D Co., Ltd. (72) Katsumi Yamazaki 1-4-1, Chuo, Wako-shi, Saitama Stock Inside Honda R & D Co., Ltd. (72) Inventor Yoshihiro Yoshida 1-4-1 Chuo, Wako-shi, Saitama Prefecture Incorporated Honda R & D Co., Ltd. Technical Research Institute (56) References JP-A-61-153057 (JP, A) JP-A-57-73266 (JP, A) JP-A-60-147579 (JP, A) JP-B-59-22070 (JP, A) B1)

Claims (2)

(57) [Claims] A plurality of cylinder holes (1) rotatable about a rotation axis and arranged annularly around the rotation axis.
8) and the cylinder bore (1).
8), and a swash plate (2) having a front surface in contact with the outer ends of the plungers (19).
0) and the back of the swash plate (20)
And a swash plate holder (22) arranged to be tiltable around a trunnion axis (O ₂ ) orthogonal to the rotation axis, and a fixed swash plate supporting the swash plate holder (22). In the variable displacement type swash plate type hydraulic device comprising an anchor (23), the opposing surfaces of the swash plate holder (22) and the swash plate anchor (23) are connected to the rotation axis of the cylinder (17) and the trunnion axis (O ₂ ). A trunnion axis is formed on a spherical surface (f ₁ , f ₂ ) centered on the intersection and on the periphery of the swash plate holder (22).
(O ₂ ) and an outer peripheral arc on the swash plate anchor (23) side
Protruding semi-cylindrical trunnion shaft (22a) facing the surface
And the trunnion shaft (22a) is rotatably engaged.
The swash plate anchor (23)
Formed in, the swash plate holder (22), a peripheral portion in which it separates away from the trunnion axis (O _2), characterized in that the concatenation of the shift control device (27) for tilting the swash plate holder (22) ,
Variable capacity swash plate type hydraulic device. 2. A one of claim 1, shea Linda (17), the swash plate (20), the swash plate holder (2
2) and an output shaft (31) penetrating the swash plate anchor (23)
And the swash plate anchor (23) is connected to the output shaft (31) via a bearing (30) so as not to move in the axial direction, and is connected to the casing (4) so as not to rotate. A variable displacement swash plate type hydraulic device.