JP2017203399A - Tilt angle control device for fluid pressure rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a tilt angle of a fluid pressure rotary machine to be adjusted to an optional angle in response to an electric signal.SOLUTION: A tilt angle control device for a liquid pressure rotary machine comprises a servo-piston moving in a flow rate increasing direction and a flow rate decreasing direction; a first housing forming a first pressure receiving chamber and a second pressure receiving chamber between it and the servo-piston; a second housing provided with a storing hole extending in parallel with an axial direction of the servo-piston; a reference flow passage communicated with a supply passage formed at a casing of the liquid pressure rotary machine with the first pressure receiving chamber; a spool arranged in the storing hole to communicate the second pressure receiving chamber with one of the supply passage and a tank in response to the moving direction when it is moved from a pressure adjusting position; a feed-back piston arranged in the storing hole and connected to the servo-piston by a feed-back lever; a spring for biasing the spool and the feed-back lever in such a way that they are moved away from each other; and a solenoid for pressing the spool from an opposite side of the spring with a pressing force that is proportional to a command current.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a tilt angle control device for a variable capacity hydraulic rotating machine.

  The variable capacity hydraulic rotating machine includes a hydraulic pump capable of changing the discharge flow rate according to the tilt angle and a hydraulic motor capable of changing the rotational speed according to the tilt angle. The tilt angle of such a hydraulic rotary machine is controlled by a tilt angle control device.

  For example, Patent Document 1 discloses a tilt angle control device 100 for a hydraulic motor 110 as shown in FIG. The tilt angle control device 100 switches the tilt angle of the hydraulic motor 110 in two steps by an electric signal.

  Specifically, the tilt angle control device 100 includes a servo piston 120 that moves in a flow rate increasing direction that increases the tilt angle of the hydraulic motor 110 and a flow rate decreasing direction that decreases the tilt angle. Includes a housing 130 forming a first pressure receiving chamber 131 and a second pressure receiving chamber 132. The first pressure receiving chamber 131 is for moving the servo piston 120 in the flow rate increasing direction, and the second pressure receiving chamber 132 is for moving the servo piston 120 in the flow rate decreasing direction. The cross-sectional area of the second pressure receiving chamber 132 is larger than the cross-sectional area of the first pressure receiving chamber 131.

  A hydraulic pressure (the higher pressure of the pair of supply / discharge passages 111 and 112) flowing into the hydraulic motor 110 is guided to the first pressure receiving chamber 131. The second pressure receiving chamber 132 is connected to the electromagnetic valve 140. The solenoid valve 140 communicates the second pressure receiving chamber 132 with the tank when the command current is not supplied. Thereby, the tilt angle of the hydraulic motor 110 is maximized. On the other hand, the electromagnetic valve 140 guides the hydraulic pressure flowing into the hydraulic motor 110 to the second pressure receiving chamber 132 when the command current is supplied. As a result, the tilt angle of the hydraulic motor 110 is minimized.

International Publication No. 2014/141849

  By the way, regarding the tilt angle of the hydraulic rotating machine, there is a demand for adjusting the tilt angle to an arbitrary angle in accordance with an electric signal.

  Therefore, an object of the present invention is to make it possible to adjust the tilt angle of a hydraulic rotary machine to an arbitrary angle in accordance with an electrical signal.

  In order to solve the above-described problems, the present invention provides a servo piston that moves in a flow rate increasing direction that increases a tilt angle of a variable displacement hydraulic rotating machine and a flow rate decreasing direction that decreases the tilt angle, and the servo A second pressure receiving chamber for moving the piston in the direction of increasing the flow rate and a second pressure receiving chamber for moving the servo piston in the direction of decreasing the flow rate and having a larger effective sectional area than the first pressure receiving chamber. A first housing that forms a pressure receiving chamber with the servo piston, and a second housing hole that is adjacent to the first housing on the side of the servo piston and extends parallel to the axial direction of the servo piston. A housing, a supply passage formed in a casing of the hydraulic rotary machine, a reference flow path communicating with the first pressure receiving chamber, and a housing for the second pressure receiving chamber are disposed in the receiving hole. A spool that communicates the second pressure receiving chamber with one of the supply path and the tank according to a moving direction when moved from a pressure adjusting position that is cut off from both the path and the tank; and a feedback piston disposed in the accommodation hole; A feedback lever that connects the servo piston and the feedback piston, a spring that biases the spool and the feedback lever away from each other, and a pressing force proportional to a command current from the opposite side of the spring. There is provided a tilt angle control device for a hydraulic rotary machine, comprising a solenoid that presses a spool.

  According to said structure, if the command electric current to a solenoid is changed in the state in which a spool is located in a pressure regulation position, the pressure guide | induced to a 2nd pressure receiving chamber will change and a servo piston will move. When the servo piston moves, the feedback piston also moves, so the urging force of the spool by the spring changes. Then, when the pressing force of the spool by the solenoid and the biasing force of the spool by the spring are balanced, the spool is again positioned at the pressure adjusting position. By such a principle, the servo piston moves by the amount of change in the command current to the solenoid (that is, the tilt angle of the hydraulic rotating machine changes). Therefore, the tilt angle of the hydraulic rotary machine can be adjusted to an arbitrary angle according to the electrical signal.

  For example, the tilt angle control device is a sleeve that is disposed in the accommodation hole and through which the spool is inserted, and is connected to the input port connected to the reference flow path and the second pressure receiving chamber. A sleeve having an output port may be further provided, and the spool may have a land portion that opens and closes the output port.

  The spool has an enlarged diameter portion at an end portion on the solenoid side, and the solenoid includes a plunger for pressing the spool, a fixed magnetic pole penetrating the plunger, and a movable iron core to which the plunger is fixed. And a cylindrical portion surrounding the enlarged diameter portion of the spool, and the tilt angle control device is disposed in the receiving hole and is pressed against the cylindrical portion of the solenoid by a spring When the commanded current is supplied to the solenoid and the movable iron core is advanced toward the fixed magnetic pole, the diameter-expanded portion becomes the stopper ring before the movable iron core contacts the fixed magnetic pole. You may contact.

  If the fixed magnetic pole of the solenoid is used as a stopper for the movable iron core to set the stroke end of the spool, the tilt angle is not affected by the command current near the stroke end due to the adsorption of the movable iron core to the fixed magnetic pole. May change rapidly. This phenomenon occurs even when a current dither is applied to the solenoid (when a command current to the solenoid is vibrated). On the other hand, if the stroke end of the spool is set using a stopper ring arranged in the accommodation hole, the continuous change of the tilt angle by the command current can be ensured even in the vicinity of the stroke end.

  According to the present invention, the tilt angle of the hydraulic rotating machine can be adjusted to an arbitrary angle according to the electrical signal.

1 is a hydraulic circuit diagram of a tilt angle control device for a hydraulic rotary machine according to an embodiment of the present invention. It is a graph which shows the relationship between the command current to the solenoid in 1st Embodiment, and a tilt angle. It is sectional drawing of the tilt angle control apparatus shown in FIG. FIG. 4 is an enlarged view around a servo piston in FIG. 3. FIG. 4 is an enlarged view around the spool in FIG. 3. It is a hydraulic-pressure circuit diagram of the tilt angle control apparatus of a modification. It is a hydraulic-pressure circuit diagram of the tilt angle control apparatus of another modification. It is a hydraulic-pressure circuit diagram of the tilt angle control apparatus of the conventional hydraulic motor.

  FIG. 1 shows a tilt angle control device 2A of a variable capacity hydraulic rotating machine 1 according to an embodiment of the present invention. In the present embodiment, the hydraulic rotary machine 1 is a hydraulic motor 1A. However, the hydraulic rotary machine 1 may be a hydraulic pump.

  In the present embodiment, the tilt angle control device 2A is a negative type in which a command current to a solenoid 9 (to be described later) and a tilt angle (that is, displacement volume) have a negative correlation as shown in FIG. However, the tilt angle control device of the present invention may be a positive type in which the command current and the tilt angle have a positive correlation.

  As shown in FIGS. 1 and 3, the hydraulic motor 1 </ b> A has a structure in which a swash plate 11 and a cylinder block 12 are wrapped in a first casing 13 and a second casing 14. A pair of supply / discharge passages 1 a and 1 b is formed in the first casing 13 that supports the cylinder block 12. The second casing 14 is a cover having a hollow inside. A space surrounded by the first casing 13 and the second casing 14 is filled with hydraulic fluid (typically hydraulic fluid) for operating the hydraulic motor 1A, and communicates with the tank.

  The tilt angle control device 2A includes a first housing 3A integrated with the first casing 13 of the hydraulic motor 1A, and a second housing 3B attached to the first housing 3A. However, the first housing 3 </ b> A may be a separate body from the first casing 13. In this case, the second housing 3B may be integrated with the first housing 3A.

  Servo piston 4 is slidably held in first housing 3A. The second housing 3B is adjacent to the first housing 3A on the side of the servo piston 4. In the present embodiment, the axial direction of the servo piston 4 is parallel to the axial direction of the hydraulic motor 1A, but the axial direction of the servo piston 4 may be inclined with respect to the axial direction of the hydraulic motor 1A. Hereinafter, for convenience of explanation, in the axial direction of the hydraulic motor 1A, the second casing 14 side (left side in FIG. 3) is referred to as the front, and the first casing 13 side (right side in FIG. 3) is referred to as the rear.

  The servo piston 4 is connected to the swash plate 11 of the hydraulic motor 1A by a rod 21 extending in the front-rear direction. More specifically, the front end of the rod 21 is connected to the swash plate 11 by a pin 22a, and the rear end of the rod 21 is connected to the front end of the servo piston 4 by a pin 22b. However, instead of the connection by the pin 22a, the swash plate 11 may be pressed against the front end portion of the rod 21 by a spring. In this case, the rod 21 may be omitted.

  When the servo piston 4 moves backward, the tilt angle of the hydraulic motor 1A, which is the angle of the swash plate 11 with respect to the plane orthogonal to the axial direction of the hydraulic motor 1A, increases, and when the servo piston 4 moves forward, The tilt angle of the pressure motor 1A is reduced. That is, with respect to the servo piston 4, the rear is the flow rate increasing direction and the front is the flow rate decreasing direction.

  As shown in FIG. 4, the first housing 3 </ b> A forms a first pressure receiving chamber 31 and a second pressure receiving chamber 32 with the servo piston 4. The first pressure receiving chamber 31 is for moving the servo piston 4 in the flow rate increasing direction (backward), and the second pressure receiving chamber 32 is for moving the servo piston 4 in the flow rate decreasing direction (forward). is there. The effective cross-sectional area of the second pressure receiving chamber 32 is larger than the effective cross-sectional area of the first pressure receiving chamber 31. The effective cross-sectional area will be described later.

  The servo piston 4 includes a peripheral wall 41 that extends in the front-rear direction, a bottom wall 42 that closes the inside of the peripheral wall 41 from the rear, and a flange 43 that protrudes radially outward from the rear end portion of the peripheral wall 41. In the present embodiment, the rear surface of the flange 43 is flush with the rear surface of the bottom wall 42, but they may be displaced in the front-rear direction. The rear end portion of the rod 21 described above is inserted into the front end portion of the peripheral wall 41. The first pressure receiving chamber 31 described above is a space facing the front surface of the flange 43 and the outer peripheral surface of the peripheral wall 41, and the second pressure receiving chamber 32 is a space facing the rear surface of the flange 43 and the rear surface of the bottom wall 42.

  The effective sectional area of the first pressure receiving chamber 31 described above is an area between the outer peripheral surface of the flange 43 and the outer peripheral surface of the peripheral wall 41 when viewed from the axial direction of the servo piston 4. The cross-sectional area is an area between the outer peripheral surface of the flange 43 and the peripheral surface of a shaft portion 23b of the defining member 23 described later when viewed from the axial direction of the servo piston 4.

  In the present embodiment, since the hydraulic rotary machine 1 is the hydraulic motor 1A, the first pressure receiving chamber 31 is connected to the pair of supply / discharge paths 1a and 1b by the reference flow path 36. The reference flow path 36 includes one main flow path connected to the first pressure receiving chamber 31 and two branch paths connected to the pair of supply / discharge paths 1a and 1b. Each branch passage is provided with a check valve 3a. That is, the reference flow path 36 communicates the first pressure receiving chamber 31 with the higher pressure supply / discharge path of the pair of supply / discharge paths 1 a, 1 b. Of the supply / discharge passages 1a and 1b, the higher pressure functions as a supply passage for supplying hydraulic fluid to the hydraulic motor 1A, and the lower pressure as a discharge passage for discharging hydraulic oil from the hydraulic motor 1A. Function. On the other hand, the second pressure receiving chamber 32 is connected to an output port 73 of the sleeve 7 which will be described later by a pressure adjusting path 38. The pressure adjusting path 38 will be described later.

  The servo piston 4 can move forward until it contacts the defining member 23. That is, the defining member 23 defines the minimum tilt angle. The defining member 23 is a rod-shaped member extending in the front-rear direction.

  More specifically, as shown in FIG. 4, the defining member 23 includes a head 23 a located in the peripheral wall 41 of the servo piston 4, and a shaft portion 23 b that extends rearward from the head 23 a through the bottom wall 42. Yes. A screw thread (not shown) is formed on the rear portion of the shaft portion 23b. The defining member 23 is fixed to the first housing 3 </ b> A via a fixing member 24 having a screw hole and a nut 25.

  As shown in FIG. 3, the second housing 3 </ b> B is provided with a receiving hole 33 that extends parallel to the axial direction of the servo piston 4. In the present embodiment, the accommodation hole 33 penetrates the second housing 3B in the front-rear direction. The front opening of the receiving hole 33 is closed by a cap 34 attached to the front surface of the second housing 3B, and the rear opening of the receiving hole 33 is closed by a solenoid 9 attached to the rear face of the second housing 3B. ing.

  In the accommodation hole 33, a feedback piston 54, a sleeve 7 and a spool 8 are arranged. The feedback piston 54 is located on the front side of the accommodation hole 33, and the sleeve 7 is located on the rear side of the accommodation hole 33. The spool 8 is inserted through the sleeve 7. A first spring 61 and a spring seat 62 are disposed between the feedback piston 54 and the spool 8.

  The feedback piston 54 is slidably held in the second housing 3B. The feedback piston 54 is connected to the servo piston 4 by a feedback lever 51. The feedback lever 51 has a length straddling the servo piston 4 and the feedback piston 54 and is supported by a pin 52 so as to be swingable at a substantially central position. The pin 52 is fixed to the second housing 3B.

  More specifically, the feedback lever 51 has one end that engages with the servo piston 4. An engagement hole 44 (see FIG. 4) is formed in the front end portion of the peripheral wall 41 of the servo piston 4, and one end of the feedback lever 51 is inserted into the engagement hole 44. On the other hand, an engagement pin 53 is provided at the other end of the feedback lever 51.

  The feedback piston 54 is a tubular member, and is provided with a slit 55 extending in a direction orthogonal to the axial direction. An engagement pin 53 provided at the other end of the feedback lever 51 is engaged with the slit 55. Therefore, when the servo piston 4 moves forward, the feedback piston 51 moves backward by the clockwise swing of the feedback lever 51 in FIG. 3, and when the servo piston 4 moves backward, the feedback lever 51 in FIG. The feedback piston 54 moves forward by the counterclockwise swing.

  On the inner circumferential surface of the feedback piston 54, a stepped portion 56 is formed by expanding the diameter on the rear side portion, and the front side portion of the first spring 61 is inserted into the stepped portion 56. The first spring 61 presses the front end portion of the spool 8 via the spring seat 62. In other words, the first spring 61 biases the feedback piston 54 and the spool 8 so as to be separated from each other. However, depending on the shape of the spool 8, the first spring 61 may directly press the front end portion of the spool 8.

  As shown in FIG. 5, a ring-shaped protrusion 35 is formed in the approximate center of the accommodation hole 33. The sleeve 7 is pressed against the protrusion 35 by a second spring 63 disposed in the accommodation hole 33.

  In the sleeve 7, a tank port 72, an output port 73, and an input port 71 are formed in order from the front side. Each of the tank port 72, the output port 73, and the input port 71 includes a circumferentially continuous groove formed on the outer peripheral surface of the sleeve 7 and a plurality of through holes extending from the groove to the inner peripheral surface of the sleeve 7. Is done.

  As shown in FIG. 1, the input port 71 is connected to the main flow path of the reference flow path 36 by the input path 37, and the tank port 72 is connected to the tank by the tank path 74. In the present embodiment, the contact between the inner side of the sleeve 7 and the front side of the projection 35 of the accommodation hole 33 may be cut off by the contact of the spring seat 62 with the sleeve 7. The tank port 72 is for coping with the disconnection. However, the tank port 72 can be omitted when communication between the inside of the sleeve 7 and the front side of the projection 35 of the accommodation hole 33 is always ensured. As described above, the output port 73 is connected to the second pressure receiving chamber 32 by the pressure adjusting path 38.

  The pressure regulating path 38 is provided with a throttle 3b. The pressure adjusting path 38 is connected to a bypass path 39 that bypasses the throttle 3b. The bypass passage 39 is provided with a check valve 3c that allows a flow from the second pressure receiving chamber 32 to the output port 73 but prohibits a flow from the output port 73 to the second pressure receiving chamber 32.

  The spool 8 is normally located at a pressure adjusting position that blocks the second pressure receiving chamber 32 from both the supply path (the higher pressure of the supply / discharge paths 1a and 1b) and the tank. Then, when the spool 8 moves from the pressure adjusting position, the spool 8 communicates with the one of the supply path and the tank according to the moving direction. Specifically, as shown in FIG. 5, the spool 8 includes a first small diameter portion 81, a first land portion 82, a second small diameter portion 83, a second land portion 84, a third small diameter portion 85, and an enlarged diameter portion 86. These portions 81 to 86 are arranged in this order from the front side. That is, the enlarged diameter portion 86 is located at the rear end portion (end portion on the solenoid 9 side) of the spool 8.

  The first land portion 82 closes the output port 73 when the spool 8 is located at the pressure adjusting position, and opens the output port 73 when the spool 8 moves from the pressure adjusting position. When the spool 8 moves rearward from the pressure adjusting position, the output port 73 passes through the annular flow path between the first small diameter portion 81 and the inner peripheral surface of the sleeve 7 and the front side portion of the housing hole 33 and the tank It communicates with port 72. Conversely, when the spool 8 moves forward from the pressure adjusting position, the output port 73 communicates with the input port 71 through the annular flow path between the second small diameter portion 83 and the inner peripheral surface of the sleeve 7. The second land portion 84 serves to close the gap between the second small diameter portion 83 and the inner peripheral surface of the sleeve 7 from the rear.

  The solenoid 9 presses the spool 8 from the side opposite to the first spring 61 with a pressing force proportional to the command current supplied to the solenoid 9. Specifically, as shown in FIG. 5, the solenoid 9 includes a plunger 93 extending in the front-rear direction for pressing the rear end portion of the spool 8, a fixed magnetic pole 92 penetrating the plunger 93, and a rear end of the plunger 93. Includes a movable iron core 94 that is fixed. Further, the solenoid 9 includes a cylindrical portion 91 that is inserted into the accommodation hole 33 and surrounds the enlarged diameter portion 86 of the spool 8.

  On the other hand, a stopper ring 64 is disposed in the accommodation hole 33 in the vicinity of the cylindrical portion 91. The stopper ring 64 is pressed against the cylindrical portion 91 by the second spring 63 described above. The inner diameter of the stopper ring 64 is smaller than the diameter of the enlarged diameter portion 86 of the spool 8.

  When the spool 8 is located at the pressure adjusting position, a gap S <b> 2 is formed between the enlarged diameter portion 86 of the spool 8 and the stopper ring 64. The gap S2 is smaller than the gap S1 between the movable iron core 94 of the solenoid 9 and the fixed magnetic pole 92. For this reason, when the command current is supplied to the solenoid 9 and the movable iron core 94 is advanced toward the fixed magnetic pole 92, the diameter-expanded portion 86 of the spool 8 stops the stopper before the movable iron core 94 contacts the fixed magnetic pole 92. It abuts on the ring 64.

  A current dither is applied to the solenoid 9. That is, the command current to the solenoid 9 is vibrated. By such a current dither, the spool 8 moves stably. However, the current dither need not be applied to the solenoid 9.

  In the tilt angle control device 2A having the above-described configuration, when the command current to the solenoid 9 is changed in a state where the spool 8 is located at the pressure adjusting position, the pressure guided to the second pressure receiving chamber 32 changes, and the servo piston 4 Moving. When the servo piston 4 moves, the feedback piston 54 also moves, so that the urging force of the spool 8 by the first spring 61 changes. When the pressing force of the spool 8 by the solenoid 9 and the urging force of the spool 8 by the first spring 61 are balanced, the spool 8 is again positioned at the pressure adjusting position. By such a principle, the servo piston 4 moves by the amount of change in the command current to the solenoid 9 (that is, the tilt angle of the hydraulic motor 1A changes). Therefore, the tilt angle of the hydraulic motor 1A can be adjusted to an arbitrary angle according to the electrical signal.

  In addition, in this embodiment, the position of the servo piston 4 is fed back by the urging force of the first spring 61, so that the stroke of the spool 8 is sufficient even if it is short. Therefore, a small solenoid 9 can be used.

  Furthermore, in the present embodiment, a stopper ring 64 for contacting the enlarged diameter portion 86 of the spool 8 is disposed in the accommodation hole 33. When the fixed magnetic pole 92 of the solenoid 9 is used as a stopper for the movable iron core 94 in order to set the stroke end of the spool 8, the command current is increased in the vicinity of the stroke end due to the adsorption of the movable iron core 94 to the fixed magnetic pole 92. Regardless of this, the tilt angle may change abruptly. This phenomenon occurs even when current dither is applied to the solenoid 9. On the other hand, if the stroke end of the spool 8 is set using the stopper ring 64 disposed in the accommodation hole 33, the continuous change of the tilt angle by the command current can be secured even in the vicinity of the stroke end. .

(Other embodiments)
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

  For example, as shown in FIG. 6, when the hydraulic rotary machine 1 is a hydraulic pump 1B, the reference flow path 36 may be a single flow path branched from the discharge path 1d. Thereby, the tilt angle control device 2B of the hydraulic pump 1B can be realized. The hydraulic pump 1B has the same structure as the hydraulic motor 1A except that it has a suction path 1c and a discharge path 1d instead of the pair of supply / discharge paths 1a and 1b.

  Further, as shown in FIG. 7, a pin 52 for swingably supporting the feedback lever 51 is disposed on the opposite side of the servo piston 4 with respect to the feedback piston 54, and the input port 71 of the sleeve 7 and the tank port 72 are If the positions are switched, the positive tilt angle control device 2C can be realized. This modification can also be applied to the tilt angle control device 2B of the hydraulic pump 1B shown in FIG.

  Further, the sleeve 7 may be omitted, and the input port 71, the tank port 72, and the output port 73 may be formed in the second housing 3B.

1 Hydraulic rotating machine 1a, 1b Supply / exhaust path (supply path)
1c Discharge path (supply path)
13, 14 Casings 2A to 2C Tilt angle control device 3A First housing 3B Second housing 31 First pressure receiving chamber 32 Second pressure receiving chamber 34 Housing hole 35 Reference flow path 4 Servo piston 51 Feedback lever 54 Feedback piston 61 First spinning 63 Second spring 64 Stopper ring 7 Sleeve 71 Input port 72 Tank port 73 Output port 8 Spool 82, 84 Land portion 86 Expanded portion 9 Solenoid 91 Cylindrical portion 92 Fixed magnetic pole 93 Plunger 94 Movable iron core

Claims (3)

A servo piston that moves in a flow rate increasing direction that increases the tilt angle of the variable displacement hydraulic rotating machine and a flow rate decreasing direction that decreases the tilt angle;
A first pressure receiving chamber for moving the servo piston in the flow rate increasing direction and a second pressure receiving chamber for moving the servo piston in the flow rate decreasing direction and having an effective sectional area larger than that of the first pressure receiving chamber. A first housing forming a second pressure receiving chamber with the servo piston;
A second housing provided on the side of the servo piston adjacent to the first housing and provided with a receiving hole extending parallel to the axial direction of the servo piston;
A supply passage formed in a casing of the hydraulic rotary machine and a reference passage communicating the first pressure receiving chamber;
When the second pressure receiving chamber is moved from a pressure adjusting position that is disposed in the accommodation hole and blocks the second pressure receiving chamber from both the supply passage and the tank, the second pressure receiving chamber is moved to one of the supply passage and the tank according to the moving direction. A spool to communicate with,
A feedback piston disposed in the receiving hole;
A feedback lever connecting the servo piston and the feedback piston;
A spring that biases the spool and the feedback lever away from each other;
A solenoid that presses the spool from the opposite side of the spring with a pressing force proportional to the command current;
A tilt angle control device for a hydraulic rotary machine. A sleeve disposed in the accommodation hole, into which the spool is inserted, further comprising an input port connected to the reference flow path and an output port connected to the second pressure receiving chamber;
The tilt angle control device for a hydraulic rotary machine according to claim 1, wherein the spool has a land portion that opens and closes the output port. The spool has an enlarged diameter portion at an end portion on the solenoid side,
The solenoid includes a plunger for pressing the spool, a fixed magnetic pole penetrating the plunger, a movable iron core to which the plunger is fixed, and a cylindrical portion surrounding the enlarged diameter portion of the spool. ,
A stopper ring disposed in the receiving hole and pressed against the cylindrical portion of the solenoid by a spring;
When the command current is supplied to the solenoid and the movable iron core is advanced toward the fixed magnetic pole, the diameter-expanded portion contacts the stopper ring before the movable iron core contacts the fixed magnetic pole. The tilt angle control device for a hydraulic rotating machine according to claim 1 or 2.

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