JPH0720445Y2 - Swash plate type hydraulic system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a swash plate type hydraulic device which may be a swash plate type hydraulic pump, a hydraulic motor, or a hydraulic transmission having both a hydraulic pump and a hydraulic motor. .

<Prior Art> As such a hydraulic device, a cylinder block having a plurality of axial cylinders rotatably supported at its ends and annularly arranged around a rotation axis, and each cylinder It has a received plunger, a swash plate tiltably supported with respect to the case so as to slidably contact the free end of the plunger, and actuator means for tilting the swash plate. Conventionally, there has been known a swash plate type hydraulic device in which a retracting stroke of a plunger with respect to a cylinder is variable.

<Problems to be solved by the invention> When such a swash plate type hydraulic device is applied to a continuously variable transmission for an automobile, a top speed can be obtained when the intake / discharge amount of the hydraulic motor is minimum. Generally, in automobile transmissions, the efficiency at the top speed is important, and the angular accuracy of the swash plate at the top position is an important factor. This swash plate angle accuracy, the swash plate support position accuracy,
The positional accuracy and stroke accuracy of the actuator means that gives the swash plate angle are involved, but it is extremely difficult to completely control all the mechanical accuracy of these.

Japanese Patent Publication No. 39-3717 discloses a structure in which a stopper member that comes into contact with the outer peripheral portion of the front surface of the swash plate is integrally provided with the cylinder on the end plate that closes the opening of the case. According to this, when the stopper member or the swash plate is worn out after a long period of use and the neutral position of the swash plate is deviated, the adjustment of the thickness of the liner provided on the joint surface between the outer case 3 and the end plate is performed. However, since the stopper member and the cylinder are formed in the same member,
Changing the thickness of the liner will change the position of the cylinder. When the stopper reaches the wear limit, the end plate must be replaced.

In view of the above problems of the prior art, a main object of the present invention is to provide a swash plate type hydraulic device provided with an improved stopper member so that adjustment and replacement can be easily performed.

<Means for Solving the Problems> According to the present invention, such an object is such that each end of the case is rotatably attached to a case composed of a first part and a second part that are formed separately in the axial direction. A cylinder block having a plurality of axial cylinders supported and annularly arranged about a rotation axis, a plunger received by each of the cylinders, and the case so as to be in sliding contact with the free end of the plunger. A swash plate that is tiltably supported, and actuator means that is fixedly installed in the second portion of the case to tiltably drive the swash plate, and the cylinder according to the tilt angle of the swash plate. In the swash plate type hydraulic device in which the retracting stroke of the plunger with respect to the swash plate is variable, a stopper member that can come into contact with the back surface of the swash plate to define the minimum tilt angle of the swash plate is the first of the case. This is achieved by providing a swash plate type hydraulic device characterized in that it is fixed to the inner surface of the part by using a detachable fastening means.

<Operation> In this way, since the back surface side of the swash plate does not have any particular function, the degree of freedom in setting the area of the stopper member is increased, so that the area of the contact surface between the swash plate and the stopper member is increased. Since the surface pressure can be increased to reduce the surface pressure, it is possible to make the portion less likely to be worn. Moreover, even when the reference angle of the swash plate is deviated due to wear, it can be easily dealt with by replacing only the stopper member. In addition to this, if the swash plate support portion is provided on the same member side as the fixed portion of the actuator means, the stopper member can be positioned regardless of the connection state between the actuator means and the swash plate, so the swash plate assembly It is possible to easily position each part when attached.

<Embodiment> Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a vehicle hydraulic continuously variable transmission to which the present invention is applied. In this hydraulic continuously variable transmission, a hydraulic pump P and a hydraulic motor M that constitute a transmission are built in a transmission case 1 formed by connecting case halves 1a and 1b formed separately in the longitudinal direction. ing.

The hydraulic pump P is provided on a pump cylinder 4 connected to a spline portion 3 formed on the inner end of the input shaft 2 and on the pump cylinder 4 on a circumference concentric with the input shaft 2 in parallel with the input shaft 2. It has a large number of cylinder holes 5 formed therein and a large number of pump plungers 6 slidably fitted in the respective cylinder holes 5, and is transmitted through a flywheel 7 coupled to the outer end of the input shaft 2 and is not shown. It is driven to rotate by the power of the engine.

The hydraulic motor M is provided on a motor cylinder 8 (cylinder block) that is provided so as to surround the pump cylinder 4 and on a circle concentric with the input shaft 2 in the motor cylinder 8 and in parallel with the input shaft 2. Many cylinder holes 9 and each cylinder hole 9
And a plurality of motor plungers 10, which are slidably engaged with each other, so as to be rotatable relative to each other concentrically with the pump cylinder 4.

A pair of support shafts 11a is provided at both ends of the motor cylinder 8 in the axial direction.
11b is provided in a protruding manner, one support shaft 11a on the end wall of the right case half body 1b via the ball bearing 12, the other support shaft 11b via the needle bearing 13 of the left case half body 1a. It is supported by each end wall. A pressing plate 14 is fixed to the axial end surface of the right case half body 1b with bolts 15, and the ball bearing 12 and the support shaft 11a are prevented from moving in the axial direction with respect to the right case half body 1b. It is assembled as a unit. A spur gear 16 is integrally formed on the other support shaft 11b, and the output of the hydraulic motor M is transmitted to the outside through a differential gear device (not shown) that meshes with the spur gear 16. It is designed to get you.

Inside the motor cylinder 8, a pump swash plate 17 that is inclined with respect to each pump plunger 6 at a predetermined angle is fixed. An annular pump shoe 18 is rotatably and slidably supported on the inclined surface.

Each pump plunger 6 is formed with a bottomed hole 19 that opens toward the pump swash plate 17, and the connecting rod 20 inserted into this hole 19 is pumped via a ball joint 21a at its inner end. It is connected to the plunger 6 so as to be able to swing to some extent. Further, the connecting rod 20 projects from the bottomed hole 19 to the outside of the pump plunger 6, and is connected to the above-described pump shoe 18 via a ball joint 21b formed at the projecting end thereof so as to be swingable. .

The annular pump shoe 18 has its outer peripheral surface supported inside the motor cylinder 8 via a needle bearing 22. 6 and a pressing ring 24 that abuts a step portion 23 formed on the inner peripheral portion of the pump shoe 18 on the pump plunger side of the spring 2 compressed around the input shaft 2 via a spring holder 25. The pump shoe 18 is pressed against the pump swash plate 17 by receiving elastic force. The spring holder 25 is slidably fitted to a spline portion 27 formed on the input shaft 2,
A spherical surface is in contact with the presser ring 24. Therefore,
The spring holder 25 can evenly contact the pressing ring 24 at any mounting position to transmit the elastic force of the spring 26.

In this way, the pump shoe 18 can always rotate and slide on the pump swash plate 17 at a fixed position.

A crown gear 28 is formed on an end surface of the outer periphery of the pump shoe 18 which faces the pump cylinder 4. A bevel gear 29 that meshes with the crown gear 28 with the same number of teeth is fixedly provided on the outer peripheral portion of the pump cylinder 4. By the engagement of these crown gear 28 and bevel gear 29,
When the pump cylinder 4 is driven from the input shaft 2, the pump cylinder 4 synchronously rotationally drives the pump shoe 18. With these rotations, the pump plunger 6 running on the upside of the inclined surface of the pump swash plate 17 is
The discharge stroke is given from 17 through the pump shoe 18 and the connecting rod 20, and the pump plunger 6 running on the down side of the inclined surface is given the suction stroke.

A needle bearing 30 is provided between the outer peripheral surface of the bevel gear 29 and the inner peripheral surface of the motor cylinder 8 to improve the accuracy of concentric relative rotation between the pump cylinder 4 and the motor cylinder 8. It is getting higher.

The pump shoe 18 is a connecting rod on the contact surface with the pump swash plate 17.
A hydraulic pocket 31 is recessed at a position corresponding to 20. In order to connect the hydraulic pocket 31 to the oil chamber in the pump cylinder 4, the pump plunger 6 and the connecting rod are connected.
A series of oil holes 32, 33, 34 are bored in the 20 and the pump shoe 18. Therefore, during the operation of the pump cylinder 4, the pressure oil therein is supplied to the hydraulic pocket 31, and the pressure oil exerts pressure on the pump shoe 18 so as to support the thrust applied from the pump plunger 6 to the pump shoe 18. .
This reduces the contact pressure of the pump shoe 18 on the pump swash plate 17, and at the same time, reduces the pump shoe 18 and the pump swash plate.
The sliding surface with 17 can be lubricated.

Inside the mission case 1, each motor plunger 10
A motor swash plate 35 is tiltably supported via a pair of trunnion shafts 36 projecting from both outer sides of the motor swash plate 35 so as to face the tip end of the motor shoe 37. However, it is swingably connected to a ball joint 38 formed at the outer end of each motor plunger 10.

Each motor plunger 10 corresponds to the pump plunger 6 described above.
Similarly to the above, the motor cylinder 8 is rotated while reciprocating and repeating the expansion and contraction strokes. On this occasion,
The stroke of the motor plunger 10 is changed from 0 to the maximum by changing the inclination angle of the motor swash plate 35 from the upright position perpendicular to each motor plunger 10 to the maximum inclination position shown in the figure as described later. Can be adjusted steplessly.

The motor cylinder 8 is divided into the first to the first axial sections.
It is composed of fourth portions 8a to 8d. The first portion 8a is provided with the support shaft 11b and the pump swash plate 17, and the second portion 8b mainly guides the sliding movement of the motor plunger 10 in the cylinder hole 9. Parts are provided,
The third and fourth portions 8c and 8d are provided with a series of oil chambers 39 whose diameters are slightly expanded from the guide portion in the cylinder hole 9 described above, and the third portion 8c is formed in each cylinder hole. 5.9
The distribution board 40 is provided with an oil passage communicating therewith, and the one support shaft 11a is formed on the fourth portion 8d.
These first to fourth portions 8a to 8d are mutually joined by a plurality of bolts 41a and 41b after their joints are mutually positioned by using, for example, knock pins.

The above-mentioned input shaft 2 has an outer end portion via the needle bearing 42 in the center portion of the other support shaft 11b of the motor cylinder 8, and an inner end portion via the needle bearing 43 in the center portion of the distribution board 40. Is supported by each.

As described above, the spring 26 is contracted between the pump cylinder 4 and the spring holder 25, and the elastic force of the spring 26 presses the pump cylinder 4 to the distribution board 40 to As well as preventing oil from leaking from the rotary sliding portion, the spring reaction body 25 and the pressing ring are prevented by the elastic reaction force.
24, a pump shoe 18, and a pump swash plate 17 are supported inside the motor cylinder 8.

One support shaft 11a of the motor cylinder 8 is formed in a hollow shape, and the fixed shaft 44 is inserted into the center of the support shaft 11a. A distribution ring 45 is liquid-tightly fitted to the inner end of the fixed shaft 44 through an O-ring, and the annular end surface of the distribution ring 45 in the axial direction with respect to the rotation center of the input shaft 2. Eccentric distribution board 40
It can be slid on the end face of the. The distribution ring 45 divides the hollow portion 46 formed in the fourth portion 8d of the motor cylinder 8 into an inner oil chamber 45a and an outer oil chamber 46b.

The distribution board 40 has a discharge port 47 that communicates between the cylinder hole 5 of the pump plunger 6 and the inner oil chamber 46a in the discharge stroke.
And the cylinder hole 5 of the pump plunger 6 in the suction stroke
And an intake port 48 that communicates between the outside oil chamber 46b and the outside oil chamber 46b. Further, a large number of communication ports 49 are formed in the distribution board 40 corresponding to the cylinder holes 9, so that each cylinder hole 9 of the motor cylinder 8 communicates with the hollow portion 46 in the fourth portion 8d. To do.

The opening of the connection port 49 with respect to the hollow portion 46 is formed by the hydraulic motor M.
Is equally divided on a certain circumference centered on the rotation axis of. As described above, since the distribution ring 45 is eccentrically in sliding contact with the distribution plate 40, the connection port 49 that connects the inner oil chamber 46a and the outer oil chamber 46b is sequentially opened according to the rotation of the motor cylinder 8. Will be replaced.

In this way, between the hydraulic pump P and the hydraulic motor M,
A hydraulic closed circuit is formed via the distribution board 40 and the distribution ring 45. Therefore, when the pump cylinder 4 is driven from the input shaft 2, the high-pressure hydraulic oil generated by the discharge stroke of the pump plunger 6 passes from the discharge port 47 to the inner oil chamber 46a and the communication port 49 in communication therewith. It flows into the cylinder hole 9 of the motor plunger 10 in the expansion stroke and gives thrust to the motor plunger 10.

On the other hand, the hydraulic oil discharged by the motor plunger 10 in the contraction stroke is the communication port 49 communicating with the outer oil chamber 46b,
And through the suction port 48 into the cylinder hole 5 of the pump plunger 6 in the suction stroke. Due to such circulation of the hydraulic oil, the reaction torque applied to the motor cylinder 8 by the pump plunger 6 in the discharge stroke via the pump swash plate 17,
The motor cylinder 8 is driven by the sum of the reaction torque received by the motor plunger 10 in the expansion stroke from the motor swash plate 35.

In this case, the motor cylinder 8 with respect to the pump cylinder 4
The change ratio of is given by the following equation.

Gear ratio = rotation speed of pump cylinder 4 / motor cylinder 8
= 1 + capacity of hydraulic motor M / capacity of hydraulic pump P From the above equation, if the capacity of hydraulic motor M is changed from 0 to a certain value, the gear ratio can be changed from 1 to a certain required value. I understand.

By the way, the capacity of the hydraulic motor M depends on the motor plunger 10
Since it is determined by the stroke of the motor swash plate 35
As described above, the gear ratio can be adjusted steplessly from 1 to a certain value by tilting from the upright position to a certain inclination angle.

A hydraulic change servomotor S1 (actuator means) for tilting the motor swash plate 35 is fixedly installed in the upper portion of the right case half 1b (second portion) of the mission case 1. Then, a motor swash plate 35 is pin-coupled to the projecting end of the piston rod 50 of the change servomotor S1 projecting into the mission case 1 via a connecting member 51, and the change projecting through the holding plate 14 is projected. A cam mechanism C1 is connected to the outer end of the pilot valve 52 of the servomotor S1, and the motor swash plate 35 is remotely operated by a separate control device (not shown).

This change servomotor S1 is of a known type that hydraulically amplifies the movement of the pilot valve 52 and reciprocally drives a piston incorporated therein, and follows the movement of the pilot valve 52 given from an external control device. Thus, the piston rod 50 is driven so that the motor swash plate 35 is steplessly changed from the maximum tilt position shown by the solid line in FIG. 1, that is, the maximum gear ratio to the minimum tilt position shown by the imaginary line, that is, the minimum gear ratio. Can be shifted to.

A stopper 53 is provided between the motor swash plate 35 and the end wall of the left case half body 1a (first portion), which defines the mechanical minimum tilt position of the motor swash plate 35. ing.

The stopper 53 is screwed to the end plate portion of the left case half body 1a by a bolt 60 (fastening means). Therefore, the neutral position of the swash plate 35 can be easily and freely adjusted by replacing the stopper 53 with a stopper having an appropriate thickness as needed. Further, the back surface of the swash plate 35 is not used for any special purpose, and its pressure receiving area can be made sufficiently large, so that the stopper 53 or the contact portion on the swash plate 35 side is less likely to wear.

The fixed shaft 44 supporting the distribution ring 45 is formed in the hollow,
Short-circuit ports 54a and 54b that can communicate between the inner oil chamber 46a and the outer oil chamber 46b are formed in the peripheral wall. A cylindrical clutch valve 55 is used to open and close the ports 54a and 54b.
However, it is fitted in the hollow portion of the fixed shaft 44 so as to be rotatable relative to the fixed shaft 44 via the needle bearing 56. The clutch valve 55 is separately connected to a clutch control device (not shown), and when the short-circuit ports 54a and 54b are fully opened, the clutch is disengaged, and when the short-circuit ports 54a and 54b are half-open, the clutch is in the half-clutched state, and the fully closed state. The clutch contact state is obtained when each is set. That is, in the clutch disengaged state shown in the drawing, the inner oil chamber 46 is discharged from the discharge port 47.
The hydraulic fluid discharged to a directly flows into the suction port 48 from the outer oil chamber 46b via the short-circuit ports 54a and 54b to deactivate the hydraulic motor M, and in the clutch engagement state, the above-mentioned operation. The short-circuit flow of oil is blocked, the circulating action from the hydraulic pump P to the hydraulic motor M is performed, and normal power transmission is performed.

At the center of the hollow clutch valve 55, a hydraulic circuit connecting / disconnecting servomotor S2 is provided. The hydraulic circuit connecting / disconnecting servo motor S2 is connected to the change servo motor S1 via the cam mechanism C1, and by reciprocating the pilot valve 57 protruding from the pressing plate 14, the shoe 58 provided at the tip end thereof. Allows the discharge port 47 formed in the distributor 40 to
Liquid-tightly close the open end of the
It is designed to block the flow of hydraulic oil to a. In this cutoff state, the pump plunger 6 is hydraulically locked and the hydraulic pump P and the hydraulic motor M are directly connected to each other, and the pump cylinder 4 passes through the pump plunger 6 and the pump swash plate 17 and then the motor cylinder. 8 will be mechanically driven. The direct connection state between the hydraulic pump P and the hydraulic motor M is performed at the minimum gear ratio with the motor swash plate 35 in the upright state, that is, at the top position, and improves the power transmission efficiency from the input shaft to the output shaft. At the same time, the thrust exerted by the motor plunger 10 on the motor swash plate 35 can be reduced, and the load on each member such as the bearing can be reduced.

The right side surface of the transmission is covered with an end cover 59 to accommodate the cam mechanism C1 and the like.

In the continuously variable transmission for an automobile shown in the above embodiment, since the hydraulic motor M is a variable displacement type, the top speed can be obtained when the intake / discharge amount of the hydraulic motor is minimum. Generally, in a vehicle transmission, efficiency at top speed is important, and the motor swash plate at the top position is important.
An angle accuracy of 35 is an important factor. This swash plate angle accuracy is related to the position accuracy of the swash plate support (trunnion shaft 36) and the position accuracy and stroke accuracy of the change servo motor S1 that gives the swash plate angle. It is extremely difficult to manage.

Therefore, in the present invention, as described above, the motor swash plate 35
The maximum tilt position of the change servomotor S1 is defined by the stroke limit, and the angle 0 position of the motor swash plate 35 is on the left case half body which is a separate body from the right case half body 1b provided with the change servomotor S1. The stopper 53 fixed with the bolt 60 is used.

<Effect of the Invention> As described above, according to the present invention, one operation limit (maximum tilt position) of the swash plate is defined by the stroke limit of the actuator (change servo motor), and the other operation limit (angle 0 state). Can be carried out by a stopper fixed to a member (first part of the case) different from the member provided with the actuator (second part of the case) with detachable fastening means (bolts). Therefore, the pressure receiving area of the stopper can be increased. Therefore, even if the swash plate type hydraulic device of the present invention is applied to a vehicle transmission in which the inclination angle of the swash plate is frequently changed, the stopper member or the stopper contact surface of the swash plate is less likely to wear. The neutral position does not get out of order, the maintenance of the hydraulic system is easy, and the effect is extremely large. In addition, since the stopper can be provided on a member different from the member that supports the swash plate, positioning at the time of assembling the swash plate can be easily performed, which is also effective in improving the assembling property.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a hydraulic continuously variable transmission to which the present invention is applied. P ... hydraulic pump, M ... hydraulic motor, S1 ... change servomotor, S2 ... hydraulic circuit intermittent servomotor, C1 ... cam mechanism, 1 ... mission case, 1a / 1b ... case half, 2 ...
Input shaft, 3 ... Spline part, 4 ... Pump cylinder, 5 ...
Cylinder hole, 6 ... Pump plunger, 7 ... Flywheel, 8 ... Motor cylinder, 8a ... First part, 8b ... Second part, 8c ... Third part, 8d ... Fourth part, 9 ... Cylinder hole , 10 ... Motor plunger, 11a / 11b ... Spindle, 12 ... Ball bearing, 13 ... Needle bearing, 14 ... Presser plate, 15 ... Bolt, 16 ...
Gears, 17 ... Pump swash plate, 18 ... Pump shoe, 19 ... Bottom hole, 20 ... Connecting rod, 21a ・ 21b ... Ball joint, 22 ... Needle bearing, 23 ... Step, 24 ... Pressing ring, 25 ... Spring retention Body, 26 ... Spring, 27 ... Spline part, 28 ... Crown gear,
29 ... Bevel gear, 30 ... Needle bearing, 31 ... Hydraulic pocket, 32
・ 33 ・ 34 ... Oil hole, 35 ... Motor swash plate, 36 ... Trunnion shaft,
37 ... motor shoe, 38 ... ball joint, 39 ... oil chamber,
40 ... Distributor, 41a / 41b ... Bolt, 42/43 ... Needle bearing, 44 ... Fixed shaft, 45 ... Distributor ring, 46 ... Hollow part, 46a ... Inner oil chamber, 46b ... Outer oil chamber, 47 ... Discharge port, 48 ... Suction port, 49 ... Connection port, 50 ... Piston rod, 51 ... Connection member, 52 ... Pilot valve, 53 ... Stopper, 54a / 54b ... Short circuit port, 55 ... Clutch valve, 56 ... Needle bearing, 57 ... Pilot valve , 58 ... shoe, 59 ... end cover, 60 ... bolt,

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tsuneaki Kiyono, Tsuneaki Kiyono, 1-4-1, Chuo, Wako, Saitama, Ltd., Honda R & D Co., Ltd. (56) References JP-A-54-74963 (JP, A) 39-3717 (JP, B1)

Claims (1)

[Scope of utility model registration request] 1. A case (1) comprising a first portion (1a) and a second portion (1b) formed separately in the axial direction, each end of which is rotatably supported and which has a center of rotation. A cylinder block (8) having a plurality of axial cylinders (9) arranged annularly as a ring, a plunger (10) received by each of the cylinders, and the case so as to be in sliding contact with the free end of the plunger. The swash plate has a swash plate (35) tiltably supported with respect to the swash plate, and actuator means (S1) fixedly installed in the second portion of the case to tiltably drive the swash plate. A swash plate type hydraulic device in which a retracting stroke of the plunger with respect to the cylinder is variable according to an inclination angle, and a stopper member (53 which can contact the back surface of the swash plate to define a minimum inclination angle of the swash plate. ) Is the first part of the case A swash plate hydraulic system characterized in that it is fixed to the inner surface of the minute by using a detachable fastening means (60).