JP6447362B2 - Variable capacity swash plate type hydraulic rotating machine - Google Patents

Description

  The present invention relates to a variable capacity swash plate type hydraulic rotating machine.

  The variable capacity swash plate type hydraulic rotating machine is used as, for example, a hydraulic pump mounted on an engine-type forklift or a hydraulic motor. When used as a hydraulic pump, the variable displacement swash plate type hydraulic rotating machine can vary the discharge capacity of hydraulic oil (working fluid), and when used as a hydraulic motor, the rotational speed and torque can be varied. And A rotating shaft is rotatably supported in the housing of such a variable capacity swash plate type hydraulic rotating machine. The rotating shaft is provided with a cylinder block that rotates integrally with the rotating shaft. In the cylinder block, a plurality of cylinder bores are formed around the rotation shaft. A piston is accommodated in each cylinder bore. A shoe is provided at each piston end. Each shoe is held by a retainer plate.

  A swash plate capable of changing an inclination angle (inclination angle) with respect to a direction orthogonal to the rotation axis of the rotation shaft is accommodated in the housing. The end face on the cylinder block side of the swash plate is a flat sliding contact surface with which each shoe slides. When the rotation shaft rotates and the cylinder block rotates integrally with the rotation shaft, each piston slides around the sliding contact surface of the swash plate and each piston moves around the rotation shaft along the circumferential direction of the rotation shaft. Moving. Thereby, each piston reciprocates in the cylinder bore with a stroke corresponding to the inclination angle of the swash plate as the cylinder block rotates.

  The swash plate has a pair of sliding portions. The sliding portion has an arcuately curved sliding surface that bulges toward the opposite side of the cylinder block. The housing also includes a swash plate holding part that holds the swash plate while allowing the tilt angle of the swash plate to be changed. The swash plate holding portion has a sliding surface that extends along the sliding surfaces of the pair of sliding portions and on which the sliding surfaces slide. And the inclination angle of a swash plate is changed because the sliding surface of a pair of sliding part slides the sliding surface of a swash plate holding | maintenance part.

  By the way, since the sliding surface of the sliding portion slides on the sliding surface of the swash plate holding portion with the change of the inclination angle of the swash plate, friction occurs between the sliding surface and the sliding surface. . Therefore, for example, Patent Document 1 discloses that a groove is formed on the sliding surface of the sliding portion and hydraulic oil is supplied into the groove. The swash plate is provided with a supply hole (through hole in Patent Document 1) for supplying hydraulic oil in the cylinder bore into the groove. An orifice is provided in the middle of the supply hole. The orifice adjusts the amount of hydraulic oil supplied from the cylinder bore into the groove. The pressure of the hydraulic oil supplied into the groove generates a force that pushes the swash plate back toward the piston, and an oil film is formed between the sliding surface and the sliding surface, so that the sliding surface The surface pressure between the sliding surface and the sliding surface is reduced, and the friction between the sliding surface and the sliding surface due to the change in the inclination angle of the swash plate is reduced.

JP 2002-242825 A

  In such a variable displacement piston pump, the greater the amount of hydraulic oil supplied into the groove, the greater the force that pushes back the swash plate toward the piston due to the pressure of the hydraulic oil supplied into the groove. The oil film formed between the sliding surface and the sliding surface becomes thicker. When the thickness of the oil film formed between the sliding surface and the sliding surface increases, the surface pressure between the sliding surface and the sliding surface is likely to be reduced, and the slant due to the change in the inclination angle of the swash plate. Responsiveness of plate movement is improved. If the responsiveness of the movement of the swash plate due to the change in the swash plate angle is too good, a load is suddenly applied to the engine that drives the variable displacement piston pump when the swash plate tilt angle is changed. Therefore, it is not preferable.

  On the other hand, the smaller the amount of hydraulic oil supplied into the groove, the smaller the force that pushes back the swash plate toward the piston due to the pressure of the hydraulic oil supplied into the groove. The thickness of the oil film formed between the two is reduced. If the thickness of the oil film formed between the sliding surface and the sliding surface becomes thin, the surface pressure between the sliding surface and the sliding surface becomes difficult to be reduced. Responsiveness of the movement of the board becomes worse. If the responsiveness of the movement of the swash plate accompanying the change in the inclination angle of the swash plate is too bad, it is not preferable because it is impossible to quickly control the amount of hydraulic oil supplied to the forklift cargo handling device.

  The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a variable displacement swash plate type hydraulic pressure capable of adjusting the responsiveness of the movement of the swash plate accompanying the change of the tilt angle of the swash plate. It is to provide a rotating machine.

  A variable capacity swash plate type hydraulic rotating machine that solves the above problems is formed in a housing, a rotating shaft that is rotatably supported by the housing, a cylinder block that rotates integrally with the rotating shaft, and the cylinder block. A plurality of cylinder bores, a piston accommodated in each cylinder bore, a shoe provided at an end of the piston, and a change in an inclination angle with respect to a direction that is accommodated in the housing and orthogonal to the rotation axis of the rotation shaft And a swash plate holding portion that holds the swash plate while allowing a change in the tilt angle of the swash plate, and the swash plate has a sliding surface on which the shoe slides, A sliding portion having an arcuately curved sliding surface that bulges toward the opposite side of the cylinder block, and the swash plate holding portion extends along the sliding surface and the sliding surface A sliding surface to slide is provided, and a groove for supplying hydraulic oil is formed in the sliding surface, and hydraulic oil in the cylinder bore is supplied to the swash plate in the groove. The cylinder block is rotated with the rotation of the rotating shaft, and each piston is slidably in contact with the sliding contact surface, while each piston is around the rotating shaft. A variable displacement swash plate type hydraulic rotating machine in which the piston reciprocates with a stroke corresponding to the inclination angle of the swash plate by moving in the circumferential direction, and the supply hole is formed in the groove from the cylinder bore. A detachable mounting member having an orifice for adjusting the amount of hydraulic oil supplied to the cylinder is provided.

  According to this, by providing the attachment member in the supply hole, the amount of hydraulic oil supplied from the cylinder bore into the groove changes compared to before the attachment member is provided in the supply hole. Therefore, the force that pushes back the swash plate toward the piston due to the pressure of the hydraulic oil supplied into the groove can be adjusted, and the thickness of the oil film formed between the sliding surface and the sliding surface can be adjusted. can do. As a result, the frictional force generated between the sliding surface and the sliding surface is adjusted, so that the responsiveness of the movement of the swash plate accompanying the change in the inclination angle of the swash plate can be adjusted.

  In the variable displacement swash plate type hydraulic rotating machine, the swash plate includes a pair of sliding portions, and one sliding portion is located on the side corresponding to the piston during the discharge stroke, and the other sliding portion is provided. Preferably, the portion is located on the side corresponding to the piston during the suction stroke, and the groove is formed at least on the sliding surface of the one sliding portion.

  In the variable capacity swash plate type hydraulic rotary machine, the reaction force acting on the piston from the hydraulic oil acts on the swash plate via the piston and the shoe when the hydraulic oil is discharged by the discharge stroke of the piston, The surface pressure between the sliding surface and the sliding surface of the swash plate holding portion increases. Therefore, between the sliding surface and the sliding surface, the surface pressure on the side corresponding to the piston during the discharge stroke is higher than the surface pressure on the side corresponding to the piston during the suction stroke. Since a local load acts on the moving surface, it is difficult to change the inclination angle of the swash plate smoothly. Therefore, by forming a groove in the sliding surface of at least one sliding portion, the swash plate is moved to the piston by the pressure of the hydraulic oil supplied into the groove formed in the sliding surface of the one sliding portion. Force is pushed back, and an oil film is formed between the sliding surface of one sliding portion and the sliding surface, so that the sliding surface of one sliding portion and the sliding surface Surface pressure is reduced. As a result, a local load is unlikely to act on the sliding surface of the swash plate holding portion, and the inclination angle of the swash plate can be changed smoothly.

In the variable displacement swash plate type hydraulic rotating machine, it is preferable that an orifice is further provided on the sliding contact surface side of the supply hole than the mounting member.
According to this, the responsiveness of the movement of the swash plate accompanying the change of the inclination angle of the swash plate can be further adjusted.

  According to the present invention, it is possible to adjust the responsiveness of the movement of the swash plate accompanying the change of the tilt angle of the swash plate.

A side sectional view showing a variable capacity type piston pump in an embodiment. The perspective view of a swash plate. The longitudinal cross-sectional view of a swash plate. Sectional drawing which expands and shows the periphery of an attachment member.

  Hereinafter, an embodiment in which a variable displacement swash plate type hydraulic rotating machine is embodied as a variable displacement piston pump will be described with reference to FIGS. The variable displacement piston pump is used as a hydraulic pump mounted on an engine-type forklift.

  As shown in FIG. 1, the variable displacement piston pump 10 includes a housing 11 and a rotating shaft 12 that is rotatably supported by the housing 11. The housing 11 includes a bottomed cylindrical first housing 13 and a bottomed cylindrical second housing 14 connected to the opening side of the first housing 13.

  The bottom wall 13a of the first housing 13 is formed with an insertion hole 13h into which a portion of the rotating shaft 12 on the first housing 13 side is inserted. A portion of the rotary shaft 12 on the first housing 13 side is rotatably supported by the bottom wall 13 a of the first housing 13 via a bearing 15.

  The bottom wall 14a of the second housing 14 is formed with an insertion hole 14h into which a portion of the rotating shaft 12 on the second housing 14 side is inserted. A portion of the rotary shaft 12 on the second housing 14 side is rotatably supported by the bottom wall 14 a of the second housing 14 via a bearing 16.

An end of the rotary shaft 12 on the second housing 14 side protrudes from the second housing 14 to the outside. The end portion of the second housing 14 side of the rotary shaft 12 is connected to an engine as an external drive source through a power transmission mechanism (not shown). The rotating shaft 12 rotates by driving the engine.

  A cylinder block 17 and a swash plate 18 are accommodated in the first housing 13. The cylinder block 17 is disposed closer to the bottom wall 13 a of the first housing 13 than the swash plate 18. The cylinder block 17 is formed with a through hole 17a through which the rotary shaft 12 passes. The cylinder block 17 includes a small diameter portion 171 and a large diameter portion 172 having a larger hole diameter than the small diameter portion 171. The small diameter portion 171 is located closer to the second housing 14 than the large diameter portion 172. The cylinder block 17 rotates integrally with the rotating shaft 12 by the spline fitting of the small diameter portion 171 with the rotating shaft 12. A biasing spring 19 is interposed between the small diameter portion 171 and the bearing 15.

  The cylinder block 17 is formed with a plurality of cylinder bores 17 h around the rotary shaft 12. The plurality of cylinder bores 17h are arranged at equal intervals on a concentric circle. In each cylinder bore 17h, a piston 20 is housed so as to be able to reciprocate. A shoe 21 is provided at the end of the piston 20 on the swash plate 18 side. The piston 20 is formed with a through hole 20 h that penetrates in the axial direction of the piston 20. The shoe 21 is formed with a through hole 21 h that communicates with the through hole 20 h and penetrates the shoe 21.

  Each shoe 21 is held by an annular retainer plate 22. A pivot 23 that is fixed to the retainer plate 22 is provided inside the retainer plate 22. The urging spring 19 urges the pivot 23 toward the swash plate 18 via a pin (not shown). Thereby, the retainer plate 22 is urged toward the swash plate 18, and the shoes 21 are in close contact with the end surface of the swash plate 18 on the cylinder block 17 side.

  As shown in FIGS. 1 and 2, the swash plate 18 includes a plate-like main body portion 31 in which an insertion hole 18 h through which the rotary shaft 12 is inserted is formed. The swash plate 18 is attached to the rotating shaft 12 by inserting the rotating shaft 12 into the insertion hole 18 h. The swash plate 18 can change the inclination angle (inclination angle) with respect to the direction orthogonal to the rotation axis L of the rotation shaft 12.

  When the rotating shaft 12 rotates and the cylinder block 17 rotates integrally with the rotating shaft 12, each piston 21 slides around the end surface of the swash plate 18 on the cylinder block 17 side, and each piston 20 moves around the rotating shaft 12. It moves along the circumferential direction of the rotating shaft 12. As a result, each piston 20 reciprocates in the cylinder bore 17h with a stroke corresponding to the inclination angle of the swash plate 18 as the cylinder block 17 rotates. Therefore, the end surface of the swash plate 18 on the cylinder block 17 side is a flat sliding contact surface 18a with which the shoe 21 is in sliding contact.

  As shown in FIG. 2, the swash plate 18 includes a pair of sliding portions 32 at positions where the main body portion 31 is sandwiched from both sides. The pair of sliding portions 32 are formed integrally with the main body portion 31. A part of the pair of sliding portions 32 protrudes from the end surface of the main body portion 31 on the opposite side to the cylinder block 17, and the curved sliding surface 32 a that bulges toward the opposite side to the cylinder block 17. Have One sliding portion 32 is located on the side corresponding to the piston 20 during the discharge stroke, and the other sliding portion 32 is located on the side corresponding to the piston 20 during the suction stroke. Here, the “piston 20 in the intake stroke” refers to the piston 20 moving from the top dead center side toward the bottom dead center side. The “piston 20 during the discharge stroke” refers to the piston 20 moving from the bottom dead center side toward the top dead center side.

  As shown in FIG. 1, the inner wall of the second housing 14 is provided with a bush 25 as a swash plate holding portion that holds the swash plate 18 while allowing the inclination angle of the swash plate 18 to be changed. The bush 25 has a plate shape curved in an arc shape, and includes a sliding surface 25a that extends along the sliding surface 32a and on which the sliding surface 32a slides. The tilt angle of the swash plate 18 is changed by the sliding surfaces 32a of the pair of sliding portions 32 sliding on the sliding surface 25a.

  The swash plate 18 includes a pressed portion 33 that extends outward from an edge portion of the main body portion 31 corresponding to the top dead center of the piston 20. An accommodation recess 33 a is formed on the end face of the pressed part 33 on the cylinder block 17 side. A cylindrical contact member 34a is accommodated in the accommodating recess 33a. A part of the contact member 34a protrudes from the end surface of the pressed portion 33 on the cylinder block 17 side in a state where the contact member 34a is accommodated in the accommodation recess 33a. An accommodation recess 33 b is formed on the end surface of the pressed portion 33 opposite to the cylinder block 17. A cylindrical contact member 34b is accommodated in the accommodating recess 33b. A part of the contact member 34 b protrudes from the end surface of the pressed portion 33 opposite to the cylinder block 17 in a state where the contact member 34 b is stored in the storage recess 33 b.

  A suction port 26 and a discharge port 27 are formed on the bottom wall 13 a of the first housing 13. The suction port 26 and the discharge port 27 are formed in a semicircular arc shape extending along the circumferential direction of the rotating shaft 12. The suction port 26 is provided on the bottom wall 13a at a position where it can communicate with each cylinder bore 17h in which the piston 20 in the suction stroke is housed. The discharge port 27 is provided on the bottom wall 13a at a position where it can communicate with each cylinder bore 17h in which the piston 20 during the discharge stroke is housed.

  A valve seat 28 is provided between the cylinder block 17 and the bottom wall 13 a of the first housing 13. The valve seat 28 is formed with a communication hole 28a that communicates the suction port 26 and the cylinder bore 17h, and a communication hole 28b that communicates the discharge port 27 and the cylinder bore 17h. As the piston 20 reciprocates, the hydraulic oil is sucked into the cylinder bores 17h in which the piston 20 in the suction stroke is housed from the suction port 26 through the communication hole 28a, and the piston 20 in the discharge stroke is The hydraulic oil in each of the stored cylinder bores 17h is discharged from the discharge port 27 through the communication hole 28b.

  A piston housing recess 35 is formed on the radially outer side of the rotary shaft 12 with respect to the cylinder block 17 in the first housing 13. A control piston 36 is housed in the piston housing recess 35. A control pressure chamber 35 a is defined by the piston housing recess 35 and the control piston 36. A part of the hydraulic oil discharged from the discharge port 27 is supplied to the control pressure chamber 35a. The amount of hydraulic oil supplied to the control pressure chamber 35a is controlled by a control valve (not shown). The end surface of the control piston 36 on the swash plate 18 side is in contact with the contact member 34a.

  A bottomed cylindrical spring receiving concave member 37 is attached to the bottom wall 14 a of the second housing 14 by a screw 38. The spring receiving concave member 37 opens toward the swash plate 18. A hollow piston 39 is inserted into the spring receiving concave member 37. An inclination angle increasing spring 39 a is accommodated in the hollow piston 39. The hollow piston 39 is urged in a direction away from the bottom of the spring receiving concave member 37 by the urging force of the inclination increasing spring 39a. The end surface of the hollow piston 39 on the swash plate 18 side is in contact with the contact member 34b.

  In the variable displacement piston pump 10 configured as described above, when the amount of hydraulic oil supplied to the control pressure chamber 35a increases, the pressure in the control pressure chamber 35a increases and the control piston 36 moves toward the swash plate 18. . Then, the control piston 36 presses the swash plate 18 via the contact member 34a so as to reduce the tilt angle of the swash plate 18 against the biasing force of the tilt angle increasing spring 39a. Thereby, the inclination angle of the swash plate 18 is reduced, the stroke of the piston 20 is reduced, and the discharge capacity is reduced. On the other hand, when the amount of hydraulic oil supplied to the control pressure chamber 35a decreases, the pressure in the control pressure chamber 35a decreases, and the hollow piston 39 increases the tilt angle of the swash plate 18 by the biasing force of the tilt angle increasing spring 39a. The swash plate 18 is pressed through the contact member 34b. As a result, the inclination angle of the swash plate 18 increases, the stroke of the piston 20 increases, and the discharge capacity increases.

  As shown in FIGS. 2 and 3, the sliding surface 32 a of one sliding portion 32 is formed with a groove 40 through which hydraulic oil is supplied. The swash plate 18 is provided with a supply hole 43 for supplying hydraulic oil in the cylinder bore 17h in which the piston 20 during the discharge stroke is accommodated into the groove 40. One end of the supply hole 43 opens into the groove 40 and the other end opens into the sliding contact surface 18a. The supply hole 43 can communicate with the through hole 21 h of each shoe 21.

  As shown in FIG. 4, the supply hole 43 has a removable cylindrical shape having an orifice 50h for adjusting the supply amount of hydraulic oil supplied into the groove 40 from the cylinder bore 17h in which the piston 20 during the discharge stroke is accommodated. The mounting member 50 is provided. A male screw 50 a is formed on the outer peripheral surface of the mounting member 50. The supply hole 43 has a female screw hole 43a into which the male screw 50a is screwed. On the end surface of the attachment member 50, an engagement recess 50b is formed that can engage an attachment jig (not shown) used when attaching the attachment member 50 to the supply hole 43. Then, with the mounting jig engaged with the engaging recess 50b, the mounting member 50 is inserted into the supply hole 43 from the sliding surface 32a side, and the mounting member 50 is moved into the female screw hole 43a while operating the mounting jig. Screw against. As a result, the male screw 50 a is screwed into the female screw hole 43 a and the attachment member 50 is attached to the supply hole 43.

  An orifice 43 h is further provided on the supply hole 43 closer to the sliding contact surface 18 a than the mounting member 50. The orifice 43h adjusts the supply amount of hydraulic oil supplied into the groove 40 from the cylinder bore 17h in which the piston 20 during the discharge stroke is accommodated.

Next, the operation of this embodiment will be described.
Hydraulic oil is supplied into the groove 40 through the through holes 20h and 21h and the supply hole 43 from the cylinder bore 17h in which the piston 20 in the discharge stroke is accommodated. At this time, the supply amount of hydraulic oil supplied from the cylinder bore 17h into the groove 40 is adjusted by the orifice 43h of the supply hole 43 and the orifice 50h of the mounting member 50. And the force of pushing back the swash plate 18 toward the piston 20 is generated by the pressure of the hydraulic oil supplied into the groove 40, and between the sliding surface 32a of one sliding portion 32 and the sliding surface 25a. By forming the oil film, the surface pressure between the sliding surface 32a of the one sliding portion 32 and the sliding surface 25a is reduced. Thereby, the friction between the sliding surface 32a and the sliding surface 25a accompanying the change of the inclination angle of the swash plate 18 is reduced.

  In such a variable displacement piston pump 10, as the amount of hydraulic oil supplied into the groove 40 increases, the swash plate 18 due to the pressure of the hydraulic oil supplied into the groove 40 is pushed back toward the piston 20. The force increases and the thickness of the oil film formed between the sliding surface 32a and the sliding surface 25a increases. When the thickness of the oil film formed between the sliding surface 32a and the sliding surface 25a increases, the surface pressure between the sliding surface 32a and the sliding surface 25a is easily reduced, and the inclination angle of the swash plate 18 is increased. The responsiveness of the movement of the swash plate due to the change of is improved.

  On the other hand, the smaller the amount of hydraulic oil supplied into the groove 40, the smaller the force that pushes back the swash plate 18 toward the piston 20 due to the pressure of the hydraulic oil supplied into the groove 40. The thickness of the oil film formed between the sliding surface 25a is reduced. When the thickness of the oil film formed between the sliding surface 32a and the sliding surface 25a is reduced, the surface pressure between the sliding surface 32a and the sliding surface 25a is difficult to be reduced, and the inclination angle of the swash plate 18 is decreased. The responsiveness of the movement of the swash plate due to the change in the position becomes worse.

  Therefore, providing the mounting member 50 in the supply hole 43 changes the amount of hydraulic oil supplied from the cylinder bore 17h into the groove 40 as compared to before mounting the mounting member 50 in the supply hole 43. Accordingly, the force of pushing back the swash plate 18 toward the piston 20 due to the pressure of the hydraulic oil supplied into the groove 40 is adjusted, and the thickness of the oil film formed between the sliding surface 32a and the sliding surface 25a. Is adjusted. As a result, the frictional force generated between the sliding surface 32a and the sliding surface 25a is adjusted, so that the responsiveness of the movement of the swash plate 18 accompanying the change in the tilt angle of the swash plate 18 can be adjusted. .

In the above embodiment, the following effects can be obtained.
(1) The supply hole 43 is provided with a detachable mounting member 50 having an orifice 50h. According to this, the amount of hydraulic oil supplied from the cylinder bore 17h into the groove 40 changes compared to before the attachment member 50 is provided in the supply hole 43. Therefore, the force of pushing back the swash plate 18 toward the piston 20 due to the pressure of the hydraulic oil supplied into the groove 40 can be adjusted, and an oil film formed between the sliding surface 32a and the sliding surface 25a. The thickness of can be adjusted. As a result, since the frictional force generated between the sliding surface 32a and the sliding surface 25a is adjusted, it is possible to adjust the responsiveness of the movement of the swash plate 18 accompanying the change in the inclination angle of the swash plate 18. it can.

  (2) In the variable displacement piston pump 10, a reaction force that acts on the piston 20 from the working oil when the working oil is discharged by the discharge stroke of the piston 20 acts on the swash plate 18 via the piston 20 and the shoe 21. The surface pressure between the sliding surface 32a of the sliding portion 32 and the sliding surface 25a of the bush 25 is increased. Therefore, between the sliding surface 32a and the sliding surface 25a, the surface pressure on the side corresponding to the piston 20 during the discharge stroke is higher than the surface pressure on the side corresponding to the piston 20 during the suction stroke. In addition, since a local load acts on the sliding surface 25a, it is difficult to change the inclination angle of the swash plate 18 smoothly. Therefore, the groove 40 is formed in the sliding surface 32a of at least one of the sliding portions 32. According to this, the force of pushing back the swash plate 18 toward the piston 20 is generated by the pressure of the hydraulic oil supplied in the groove 40 formed in the sliding surface 32a of the one sliding portion 32, By forming an oil film between the sliding surface 32a of the sliding portion 32 and the sliding surface 25a, the surface pressure between the sliding surface 32a and the sliding surface 25a of one sliding portion 32 is reduced. Is done. As a result, it becomes difficult for a local load to act on the sliding surface 25a of the bush 25, and the inclination angle of the swash plate 18 can be changed smoothly.

  (3) An orifice 43 h is further provided on the supply hole 43 closer to the sliding contact surface 18 a than the mounting member 50. According to this, it is possible to further adjust the responsiveness of the movement of the swash plate 18 accompanying the change in the tilt angle of the swash plate 18.

In addition, you may change the said embodiment as follows.
In the embodiment, the orifice 43 h may not be formed closer to the sliding contact surface 18 a than the mounting member 50 in the supply hole 43.

In the embodiment, the groove 40 may be formed on the sliding surface 32 a of the other sliding portion 32.
In the embodiment, the bush 25 may not be provided on the inner wall of the second housing 14, and a swash plate holding portion that holds the swash plate 18 is formed on a part of the inner wall of the second housing 14. Also good.

In the embodiment, the main body portion 31 and the pair of sliding portions 32 may be separate members, and each sliding portion 32 may be attached to the main body portion 31 with a bolt or the like.
In the embodiment, the variable displacement swash plate type hydraulic rotating machine may be used as a hydraulic motor that rotates the rotating shaft 12 via the cylinder block 17 by hydraulic oil supplied to the cylinder bore 17h. When used as a hydraulic motor, the variable displacement swash plate type hydraulic rotating machine makes the rotation speed and torque variable.

  DESCRIPTION OF SYMBOLS 10 ... Variable displacement type piston pump (variable displacement type swash plate type hydraulic rotating machine), 11 ... Housing, 12 ... Rotating shaft, 17 ... Cylinder block, 17h ... Cylinder bore, 18 ... Swash plate, 18a ... Sliding contact surface, 20 ... Piston, 21 ... shoe, 25 ... bush as swash plate holding portion, 25a ... sliding surface, 32 ... sliding portion, 32a ... sliding surface, 40 ... groove, 43 ... supply hole, 43h ... orifice, 50 ... Mounting member, 50h ... orifice.

Claims (4)

A housing;
A rotating shaft rotatably supported by the housing;
A cylinder block that rotates integrally with the rotating shaft;
A plurality of cylinder bores formed in the cylinder block;
A piston housed in each cylinder bore;
A shoe provided at an end of the piston;
A swash plate accommodated in the housing and capable of changing an inclination angle with respect to a direction perpendicular to the rotation axis of the rotation shaft;
A swash plate holding part that holds the swash plate while allowing a change in the inclination angle of the swash plate,
The swash plate includes a sliding contact surface on which the shoe slides, and a sliding portion having an arc-shaped curved sliding surface that bulges toward the opposite side of the cylinder block,
The swash plate holding portion includes a sliding surface that extends along the sliding surface and on which the sliding surface slides,
The sliding surface is formed with a groove through which hydraulic oil is supplied.
The swash plate is formed with a supply hole for supplying hydraulic oil in the cylinder bore into the groove,
The cylinder block rotates with the rotation of the rotation shaft, and the respective pistons move around the rotation shaft in the circumferential direction of the rotation shaft while the shoes slide in contact with the sliding contact surface. A variable displacement swash plate type hydraulic rotating machine in which a piston reciprocates with a stroke corresponding to an inclination angle of the swash plate,
A variable displacement swash plate hydraulic pressure is provided in the supply hole, wherein a detachable mounting member having an orifice for adjusting a supply amount of hydraulic oil supplied from the cylinder bore into the groove is provided. Rotating machine. The swash plate includes a pair of the sliding portions,
One sliding portion is located on the side corresponding to the piston during the discharge stroke, and the other sliding portion is located on the side corresponding to the piston during the suction stroke,
The variable capacity swash plate type hydraulic rotating machine according to claim 1, wherein the groove is formed on at least a sliding surface of the one sliding portion.   The variable capacity swash plate type hydraulic rotating machine according to claim 1, wherein an orifice is further provided on the sliding surface side of the supply hole than the mounting member. The supply hole is
A first portion extending from the sliding contact surface toward the sliding surface;
A second portion that connects the first portion and the groove and extends in a direction different from the extending direction of the first portion, and is provided at a boundary between the first portion and the second portion. Is bent,
The variable capacity swash plate type hydraulic rotating machine according to claim 1, wherein the attachment member is provided in the second portion of the supply hole.