WO2017047668A1

WO2017047668A1 - Hydraulic rotary machine

Info

Publication number: WO2017047668A1
Application number: PCT/JP2016/077190
Authority: WO
Inventors: 竜乃介石川
Original assignee: Ｋｙｂ株式会社
Priority date: 2015-09-16
Filing date: 2016-09-14
Publication date: 2017-03-23
Also published as: JP2017057791A; US20190055931A1; EP3351794A1; JP6622533B2; CN108026905A

Abstract

This piston pump/motor 100 comprises: a cylinder block 2 which rotates with a shaft 1; pistons 6 which are slidably inserted into cylinders 2b formed in the cylinder block 2; shoes 20 which are rotatably connected to the tip part of the pistons 6, and are in sliding contact with the tip part; and swash plates 8 which are in sliding contact with the shoes 20. Each shoe 20 comprises: a piston sliding part 30 in sliding contact with a piston 6 and a swash plate sliding part 31 in sliding contact with a swash plate 8; a shoe body 21 to which the piston sliding part 30 and the swash plate sliding part 31 are mounted; and first engaging parts 40 and second engaging parts 50 which are respectively provided between the shoe body 21 and the piston sliding part 30 and between the shoe body 21 and the swash plate sliding part 31, and which respectively regulate the relative rotation of the shoe body 21 and the piston sliding part 30 and the relative rotation of the shoe body 21 and the swash plate sliding part 31.

Description

Hydraulic rotating machine

The present invention relates to a hydraulic rotating machine.

JP 2005-220787A discloses an axial piston pump motor including a slipper that slides on a swash plate, a cylinder block having a plurality of cylinder bores, and a plurality of pistons that reciprocate in the cylinder bores. In the axial piston pump motor disclosed in JP2005-220787A, a piston is connected to one end of a connecting rod via a resin layer, and a slipper is connected to the other end via a resin layer.

In the axial piston pump motor disclosed in JP2005-220787A, an annular groove is provided in the slipper, and the resin layer is filled in the annular groove to prevent the resin layer from falling off the slipper.

Here, in general, a resin slide portion (resin layer) attached to a sliding contact portion of a shoe (slipper) is formed by molding a resin on the shoe main body portion and then cutting the molded resin. The At the time of forming such a slide portion, if the resin is processed with a large processing force, the slide portion and the shoe main body portion may relatively rotate.

Also, during the operation of the hydraulic rotating machine, there is a possibility that the slide part and the shoe main body part relatively rotate due to the sliding resistance acting on the slide part.

Thus, when the slide part and the shoe main body are rotated relative to each other during the processing of the slide part or during the operation of the hydraulic rotating machine, the resin filled in the annular groove is worn out and falls off the shoe main part. May not be sufficiently prevented.

The present invention aims to improve the durability of a shoe in a hydraulic rotating machine.

According to an aspect of the present invention, a hydraulic rotating machine is a cylinder block that is connected to a shaft and rotates together with the shaft, and a plurality of cylinders that are formed in the cylinder block and arranged at predetermined intervals in the circumferential direction of the shaft. A piston that is slidably inserted into the cylinder and divides the volume chamber inside the cylinder, a shoe that is rotatably connected to the tip of the piston and slidably contacts the tip, and a swash plate that the shoe slidably contacts, The shoe includes a resin-made slide portion provided at at least one of a portion slidingly contacting the piston and a portion slidingly contacting the swash plate, a shoe body portion to which the slide portion is attached, and between the shoe body portion and the slide portion. And a locking portion that restricts relative rotation between the shoe main body portion and the slide portion, and the locking portion includes the shoe main body portion and the slide portion. On the other hand, has a recess portion formed, a protrusion for engaging the other to be formed recess of the shoe main body and the slide unit.

FIG. 1 is a sectional view of a hydraulic rotating machine according to an embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of the shoe of the hydraulic rotating machine according to the embodiment of the present invention. FIG. 3 is a cross-sectional view taken along line AA in FIG. 4 is a cross-sectional view taken along line BB in FIG. FIG. 5 is a cross-sectional view showing the procedure of the shoe manufacturing method and shows a state in which a swash plate slide portion is provided on the core member. FIG. 6 is a cross-sectional view showing the procedure of the shoe manufacturing method and shows a state in which the recesses of the core member are filled with resin. FIG. 7 is a cross-sectional view showing the procedure of the shoe manufacturing method and shows a state in which a reduced diameter portion is formed in the shoe.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, a hydraulic rotating machine according to an embodiment of the present invention will be described with reference to FIGS.

In the present embodiment, a case where the hydraulic rotating machine is the hydraulic rotating machine 100 using water as a working fluid will be described. The hydraulic rotating machine 100 functions as a piston pump capable of supplying water as a working fluid by rotating the shaft 1 by the power from the outside and reciprocating the piston 6, and the water fluid supplied from the outside The piston 6 reciprocates due to the pressure and the shaft 1 rotates, thereby functioning as a piston motor capable of outputting a rotational driving force. The hydraulic rotary machine 100 may function only as a piston pump, or may function only as a piston motor.

In the following description, the case where the hydraulic rotating machine 100 is used as a piston pump is illustrated, and the hydraulic rotating machine 100 is referred to as “piston pump 100”.

The piston pump 100 includes a shaft 1 that is rotated by a power source, a cylinder block 2 that is connected to the shaft 1 and rotates together with the shaft 1, and a case 3 that houses the cylinder block 2. The case 3 includes a case main body 3a that is open at both ends, a front cover 4 that seals one open end of the case main body 3a and the shaft 1 is inserted, and the other open end of the case main body 3a is sealed to the shaft 1 An end cover 5 for accommodating the end portion.

A power source is connected to one end 1a of the shaft 1 projecting outside through the insertion hole 4a of the front cover 4. The end portion 1 a of the shaft 1 is rotatably supported by the insertion hole 4 a of the front cover 4 via the first bush 16. The other end 1 b of the shaft 1 is accommodated in an accommodation recess 5 a provided in the end cover 5 and is rotatably supported via a second bush 17.

The cylinder block 2 has a through hole 2a through which the shaft 1 passes, and is splined to the shaft 1 through the through hole 2a. Thereby, the cylinder block 2 rotates as the shaft 1 rotates. The cylinder block 2 is rotatably supported by the case 3 via a slide bearing 15.

In the cylinder block 2, a plurality of cylinders 2b having openings on one end face are formed in parallel with the shaft 1. The plurality of cylinders 2 b are formed with a predetermined interval in the circumferential direction of the cylinder block 2. A cylindrical piston 6 that partitions the volume chamber 7 is inserted into the cylinder 2b so as to freely reciprocate. The front end side of the piston 6 protrudes from the opening of the cylinder 2b, and a spherical seat 6a is formed at the front end.

The piston pump 100 includes a shoe 20 that is rotatably connected to the spherical seat 6a of the piston 6 and that is in sliding contact with the spherical seat 6a, a swash plate 8 that is in sliding contact with the rotation of the cylinder block 2, and the cylinder block 2 and the end. A valve plate 9 interposed between the cover 5 and the cover 5;

The shoe 20 has a resin slide portion and a metal shoe main body portion 21. As shown in FIG. 2, the shoe main body 21 includes a receiving portion 22 that receives the spherical seat 6 a of each piston 6, and a disk-shaped flat plate portion 25 that has an outer diameter larger than that of the receiving portion 22.

The receiving part 22 has a main body part 23 formed in a cylindrical shape and a reduced diameter part 24 reduced in diameter from the main body part 23. The reduced diameter portion 24 is formed by drawing (caulking) one end portion of the main body portion 23 from the radially outer side. The other end of the main body portion 23 is connected to the flat plate portion 25.

In the receiving portion 22, a recess 22 a having an opening 22 b on the end surface is formed across the main body portion 23 and the reduced diameter portion 24. The recess 22a has a spherical inner peripheral surface, and a piston slide portion 30 as a slide portion is provided inside the recess 22a.

The piston slide portion 30 is formed by molding a resin in the concave portion 22a of the receiving portion 22. The receiving portion 22 receives the spherical seat 6a of the piston 6 via the piston slide portion 30 and is in sliding contact with the outer surface of the spherical seat 6a. Thereby, the shoe 20 can be angularly displaced with respect to the spherical seat 6a.

Further, the recess 22a has an opening diameter of the opening 22b as the reduced diameter portion 24 is formed by reducing the diameter of one end of the main body 23 in a state where the spherical seat 6a of the piston 6 is inserted inside. Is formed to be smaller than the outer diameter of the spherical seat 6a. As a result, the removal of the spherical seat 6a from the recess 22a is restricted.

The flat plate portion 25 is formed in a disc shape having a circular flat surface 25a and a cylindrical outer peripheral surface 25b, and faces the swash plate 8 (see FIG. 1). The flat plate portion 25 is provided with a swash plate slide portion 31 as a slide portion so as to cover the flat surface 25a and the outer peripheral surface 25b. The swash plate slide portion 31 is formed by molding a resin on the flat plate portion 25. The flat plate portion 25 is in sliding contact with the swash plate 8 via the swash plate slide portion 31.

Thus, the slide portion is provided at a portion where the shoe 20 comes into sliding contact with other members. That is, the shoe 20 is provided as a slide part inside the recess 22a of the receiving part 22 where the shoe 20 is in sliding contact with the spherical seat 6a of the piston 6 and is in sliding contact with the spherical seat 6a of the piston 6. And a swash plate slide portion 31 that is provided on the flat plate portion 25 of the shoe main body portion 21 that is a portion in which the shoe 20 is in sliding contact with the swash plate 8 and is in sliding contact with the swash plate 8.

The shoe 20 includes a first locking part 40 provided between the receiving part 22 and the piston slide part 30, and a second locking part 50 provided between the flat plate part 25 and the swash plate slide part 31. Also have.

The first locking portion 40 includes a first recess 41 formed on the inner surface of the main body 23 of the receiving portion 22, a first protrusion 42 provided on the piston slide portion 30 and locking to the first recess 41. Have. That is, the first locking portion 40 is provided between the main body portion 23 of the receiving portion 22 and the piston slide portion 30. As shown in FIG. 3, the first locking portions 40 are provided at four locations at equal intervals in the circumferential direction between the receiving portion 22 and the piston slide portion 30.

As shown in FIG. 2 and FIG. 3, the first dent 41 does not have a right-angled corner but is formed only by a curved surface.

The first protrusion 42 is integrally formed with the piston slide portion 30 by molding. A first protrusion 42 that engages with the first recess 41 is formed in the piston slide portion 30 by filling a part of the mold resin in the first recess 41 formed in the main body 23 of the receiving portion 22. Is done. Thereby, the relative rotation of the shoe main body 21 and the piston slide part 30 is restricted.

As shown in FIG. 2, the second locking portion 50 is formed on the second recess portion 51 formed on the outer peripheral surface 25 b of the flat plate portion 25 and the second recess portion 51 formed on the swash plate slide portion 31. A second protrusion 52. As shown in FIG. 4, the second locking portions 50 are provided at four locations at equal intervals in the circumferential direction between the flat plate portion 25 and the swash plate slide portion 31.

As shown in FIGS. 2 and 4, the second dent portion 51, like the first dent portion 41, does not have a right-angled corner and is formed only by a curved surface.

The second protrusion 52 is integrally formed with the swash plate slide portion 31 by molding. When the second recess 51 formed on the outer peripheral surface 25 b of the flat plate portion 25 is filled with a part of the mold resin, the second protrusion 52 that engages with the second recess 51 is formed on the swash plate slide portion 31. It is formed. Thereby, the relative rotation between the shoe main body 21 and the swash plate slide portion 31 is restricted, and the swash plate slide portion 31 is prevented from falling off the flat plate portion 25.

Further, if the second recess 51 is formed on the flat surface 25a facing the swash plate 8, thermal deformation when the molded resin is cooled becomes non-uniform, and the surface accuracy of the sliding surface of the swash plate slide portion 31 is reduced. May decrease. On the other hand, in the piston pump 100, since the 2nd hollow part 51 is not formed in the plane 25a but is formed in the outer peripheral surface 25b, there is no possibility of reducing the surface accuracy of a sliding surface.

As shown in FIG. 1, the swash plate 8 is fixed to the inner wall of the front cover 4 and has a sliding contact surface 8a inclined from a direction perpendicular to the axis of the shaft 1. The swash plate slide part 31 provided in the flat plate part 25 of the shoe 20 is in surface contact with the sliding contact surface 8a.

The valve plate 9 is a disc member with which the base end surface of the cylinder block 2 is in sliding contact, and is fixed to the end cover 5. The valve plate 9 includes a suction port 9a that connects the suction passage 10 and the volume chamber 7 formed in the end cover 5, a discharge port 9b that connects the discharge passage 11 and the volume chamber 7 that are formed in the end cover 5, Is formed.

Next, a method for manufacturing the shoe 20 and a method for connecting the piston 6 and the shoe 20 will be described with reference to FIGS.

In manufacturing the shoe 20, first, as shown in FIG. 5, the core member 120 having the flat plate portion 25 and the main body portion 23 is formed, and the swash plate slide portion 31 is formed on the core member 120. At this stage, the reduced diameter portion 24 is not formed at the end of the main body portion 23.

Specifically, in the formation of the swash plate slide portion 31, resin is molded on the flat plate portion 25. At the time of molding the swash plate slide portion 31, a part of the mold resin is filled in the second recess portion 51 and the second locking portion 50 is formed at the same time. Since the 2nd hollow part 51 of the 2nd latching | locking part 50 does not have a right-angled corner | angular part, it can be easily filled with mold resin in the 2nd hollow part 51, and the 2nd projection part 52 can be formed easily. it can. In addition, since the second recess 51 does not have a right-angled corner, the second protrusion 52 does not have a right-angled corner. Therefore, stress concentration at the corner is prevented, and the durability of the second recess 51 and the second protrusion 52 is improved.

After the resin is molded on the flat plate portion 25, finish processing (cutting or the like) is performed on the molded resin. Thereby, the swash plate slide part 31 which has the smooth slidable contact surface which slidably contacts with the swash plate 8 is formed. When finishing the molded resin, the second locking portion 50 restricts relative rotation between the mold resin and the core member 120. As described above, the relative rotation between the mold resin and the core member 120 due to the finishing processing force is restricted by the second locking portion 50, so that the swash plate slide portion 31 is worn during the manufacture of the shoe 20. Is prevented.

Next, the piston slide part 30 is formed inside the recess 22a of the receiving part 22.

In forming the piston slide part 30, as shown in FIG. 6, the entire recess 22a is filled with resin. When the entire recess 22a is filled with resin, a part of the mold resin is filled in the first recess 41, and the first locking portion 40 is formed. Since the first depression 41 does not have a right-angled corner like the second depression 51, the first protrusion 42 can be easily formed, and the first depression 41 and the first protrusion The durability of the portion 42 can be improved.

After the resin is molded in the recess 22a, the filled mold resin is cut to form a spherical sliding contact surface that is in sliding contact with the spherical seat 6a of the piston 6. At this time, relative rotation between the mold resin in the recess 22 a and the core member 120 is restricted by the first locking portion 40. As described above, the relative rotation between the mold resin and the core member 120 due to the processing force for processing the sliding contact surface is restricted by the first locking portion 40, so that the piston slide portion 30 at the time of manufacturing the shoe 20 is controlled. Wear is prevented.

Next, as shown in FIG. 7, the spherical seat 6 a of the piston 6 is inserted into the recess 22 a, and the end (the left end in the figure) of the main body 23 on the opening 22 b side is radially outer together with the piston slide portion 30. Then, the diameter is reduced by drawing (see arrow in FIG. 7). Thereby, the opening diameter of the opening part 22b of the recessed part 22a is formed smaller than the outer diameter of the spherical surface seat 6a of the piston 6, and the removal from the recessed part 22a of the spherical surface seat 6a is controlled.

In this way, the receiving portion 22 having the reduced diameter portion 24 and the main body portion 23 is formed, and the shoe 20 as shown in FIG. 2 is manufactured, and the shoe 20 and the piston 6 are connected.

Here, when the first locking portion 40 is provided between the reduced diameter portion 24 and the piston slide portion 30, the first protrusion 42 is a part of the main body portion 23 when the reduced diameter portion 24 is formed. At the same time, the diameter is reduced and deformed. If the first protrusion 42 is deformed in this manner, cracks or the like may occur, and the durability of the first protrusion 42 may be reduced. On the other hand, in the piston pump 100, the first locking portion 40 is provided between the piston slide portion 30 and the main body portion 23 of the receiving portion 22, and therefore is not deformed when the reduced diameter portion 24 is formed. Therefore, it is possible to prevent the durability of the first protrusion 42 from being lowered.

Next, the operation of the piston pump 100 will be described.

When the shaft 1 is rotationally driven by power from the outside and the cylinder block 2 rotates, the flat plate portion 25 of each shoe 20 slides with respect to the swash plate 8 via the swash plate slide portion 31, and each piston 6 tilts. The cylinder 2b is reciprocated by a stroke amount corresponding to the tilt angle of the plate 8. The volume of each volume chamber 7 is increased or decreased by the reciprocation of each piston 6.

Water is guided to the volume chamber 7 that is expanded by the rotation of the cylinder block 2 through the suction passage 10 of the end cover 5 and the suction port 9a of the valve plate 9. The water sucked into the volume chamber 7 is increased in pressure by the reduction of the volume chamber 7 due to the rotation of the cylinder block 2, and is discharged through the discharge port 9 b of the valve plate 9 and the discharge passage 11 of the end cover 5. As described above, in the piston pump 100, the suction and discharge of water are continuously performed as the cylinder block 2 rotates.

Thus, during the operation of the piston pump 100, the shoe 20 rotates around the shaft 1 while being in sliding contact with the swash plate 8 via the swash plate slide portion 31. Even during the operation of the piston pump 100, the relative rotation between the swash plate slide portion 31 and the flat plate portion 25 due to the sliding resistance with the swash plate 8 is restricted by providing the second locking portion 50. Is done. Therefore, wear of the swash plate slide portion 31 due to relative rotation of the swash plate slide portion 31 and the shoe main body portion 21 during the operation of the piston pump 100 is also prevented.

Further, during the operation of the piston pump 100, the piston 6 reciprocates in the cylinder 2b by rotating around the shaft 1 while the shoe 20 slides on the swash plate 8, so that the spherical seat 6a of the piston 6 and the shoe Sliding resistance also occurs between the 20 piston slide portions 30. On the other hand, by providing the first locking portion 40, relative rotation between the piston slide portion 30 and the receiving portion 22 due to sliding resistance with the spherical seat 6a of the piston 6 is also restricted. Therefore, during the operation of the piston pump 100, wear of the piston slide part 30 due to the relative rotation of the piston slide part 30 and the shoe main body part 21 is also prevented.

According to the above embodiment, the following effects are obtained.

In the piston pump 100, relative rotation between the piston slide part 30 and the receiving part 22 of the shoe main body part 21 during the formation of the piston slide part 30 and the operation of the piston pump 100 is restricted by the first locking part 40. For this reason, the piston slide part 30 is prevented from rotating relative to the shoe main body part 21 and being worn. Therefore, the piston slide part 30 is prevented from dropping off from the shoe main body part 21 and the durability of the shoe 20 can be improved.

In the piston pump 100, the second locking portion 50 allows relative rotation between the swash plate slide portion 31 and the flat plate portion 25 of the shoe main body portion 21 when the swash plate slide portion 31 is formed and when the piston pump 100 is operated. Be regulated. For this reason, the swash plate slide part 31 is prevented from rotating relative to the shoe main body part 21 and being worn. Therefore, the swash plate slide portion 31 is prevented from dropping off from the shoe main body portion 21 and the durability of the shoe 20 can be further improved.

Also, the first recess 41 of the first locking part 40 and the second recess 51 of the second locking part 50 are formed in the receiving part 22 and the flat plate part 25 of the shoe main body part 21, respectively. Thereby, the 1st protrusion part 42 and the 2nd protrusion part 52 are formed by filling the 1st hollow part 41 and the 2nd hollow part 51 with resin. Therefore, the first locking portion 40 and the second locking portion 50 can be easily formed as compared with the case where the shoe main body portion 21 is processed to form the first protruding portion 42 and the second protruding portion 52. it can.

Moreover, the 1st hollow part 41 of the 1st latching | locking part 40 and the 2nd hollow part 51 of the 2nd latching | locking part 50 are each formed only by a curved surface. Since the 1st hollow part 41 and the 2nd hollow part 51 do not have a right-angled corner | angular part, it is easy to fill with resin and the 1st projection part 42 and the 2nd projection part 52 can be formed easily. Therefore, productivity can be improved. In addition, since the first dent portion 41 and the second dent portion 51 do not have a right-angled corner, stress concentration on the corner is prevented, so the first locking portion 40 and the second locking portion The durability of the portion 50 can be improved. Furthermore, since it is easy to fill the resin, bubbles are prevented from remaining in the resin, and the durability of the first locking portion 40 and the second locking portion 50 can be further improved.

Next, a modification of this embodiment will be described.

In the above embodiment, the piston pump motor 100 using water as the working fluid has been described. Alternatively, the hydraulic fluid may be other fluid such as hydraulic fluid.

In the above embodiment, the fixed displacement type piston pump motor in which the tilt angle of the swash plate 8 is fixed has been described. Instead, the piston pump motor 100 may be a variable displacement piston pump motor that can change the tilt angle of the swash plate 8.

In the above embodiment, the shoe 20 has the piston slide portion 30 and the swash plate slide portion 31 as the slide portions. However, the shoe 20 is not limited to having both the piston slide part 30 and the swash plate slide part 31, and may have only one of them.

Moreover, in the said embodiment, the 1st hollow part 41 and the 2nd hollow part 51 are formed only by a curved surface. Instead of this, for example, as long as the shape does not have a right-angled corner such as a chamfered shape (taper chamfering or R chamfering), the first dent 41 and the second dent 51 are formed in arbitrary shapes. it can. Even in this case, the first dent 41 and the second dent 51 can be easily filled with resin and can prevent stress concentration. Furthermore, it is desirable that the first dent portion 41 and the second dent portion 51 do not have a right-angled corner, but there is a risk of damage to the first locking portion 40 and the second locking portion 50 due to stress concentration. In the case where there is no resin or when sufficient filling of the resin can be ensured, the shape may have a right-angled corner.

Moreover, in the said embodiment, the 2nd latching | locking part 50 has the 2nd hollow part 51 formed in the outer peripheral surface 25b of the flat plate part 25. FIG. Instead, the second locking portion 50 has a notch-like shape that opens to the outer peripheral surface 25b of the flat plate portion 25 and the flange surface 25c (see FIG. 2) on the opposite side of the flat surface 25a of the flat plate portion 25. You may have a hollow. In this case, the 2nd projection part 52 of the 2nd latching | locking part 50 is formed in the shape corresponding to the shape of the said hollow, and latches to a hollow. By configuring the second locking portion 50 in this way, bubbles are less likely to enter the resin.

Moreover, in the said embodiment, the 1st hollow part 41 and the 2nd hollow part 51 are provided in the shoe main body 21, and the 1st projection part 42 and the 2nd projection part 52 are the piston slide part 30 and the swash plate slide part 31, respectively. Provided. Instead, the first dent portion 41 and the second dent portion 51 are provided on the piston slide portion 30 and the swash plate slide portion 31, respectively, and the first projection portion 42 and the second projection portion 52 are provided on the shoe main body 21. It may be a thing.

Hereinafter, the configuration, operation, and effect of the embodiment of the present invention will be described together.

The piston pump / motor 100 includes a cylinder block 2 that is connected to the shaft 1 and rotates together with the shaft 1, a plurality of cylinders 2b that are formed in the cylinder block 2 and arranged at predetermined intervals in the circumferential direction of the shaft 1, and a cylinder 2b. A piston 6 that is slidably inserted into the cylinder 2b and divides the volume chamber 7 inside the cylinder 2b; a shoe 20 that is rotatably connected to the distal end portion of the piston 6 and that is in sliding contact with the distal end portion; The shoe 20 includes a resin slide portion (piston slide portion 30, swash plate slide portion 31) provided on at least one of a portion slidably contacting the piston 6 and a portion slidably contacting the swash plate 8. A shoe main body 21 to which slide parts (piston slide part 30 and swash plate slide part 31) are attached, A locking portion that is provided between the shoe portion (piston slide portion 30 and swash plate slide portion 31) and restricts relative rotation between the shoe main body portion 21 and the slide portion (piston slide portion 30 and swash plate slide portion 31). (First locking portion 40, second locking portion 50), and the locking portions (first locking portion 40, second locking portion 50) are the shoe main body portion 21 and the slide portion (piston). A depression (first depression 41, second depression 51) formed on one of the slide part 30 and the swash plate sliding part 31) and a depression (first part) formed on the other of the shoe body part 21 and the slide part. And a protrusion (first protrusion 42, second protrusion 52) to be engaged with the recess 41 and the second recess 51).

In this configuration, since the protrusions (first protrusion 42, second protrusion 52) are engaged with the recesses (first recess 41, second recess 51), the slide part (piston slide part 30, diagonal) The relative rotation between the shoe main body 21 and the mold resin during the processing of the plate slide portion 31) is restricted. Also, during the operation of the piston pump / motor 100, the relative rotation between the shoe main body 21 and the slide portion (piston slide portion 30, swash plate slide portion 31) due to sliding resistance is prevented by the lock portion (first lock portion). 40, second locking part 50). In this way, the relative rotation between the shoe main body 21 and the slide part (piston slide part 30, swash plate slide part 31) is regulated by the lock part (first lock part 40, second lock part 50). As a result, the wear of the slide part (piston slide part 30, swash plate slide part 31) during processing and the wear of the slide part (piston slide part 30, swash plate slide part 31) during operation of the piston pump / motor 100 are reduced. Both are prevented. Therefore, the durability of the shoe 20 in the piston pump / motor 100 is improved.

In the piston pump motor 100, the piston 6 has a spherical seat 6a formed at the tip, and the shoe main body 21 has a receiving portion 22 that receives the spherical seat 6a of the piston 6. 22 has a main body portion 23 and a reduced diameter portion 24 that is reduced in diameter from the main body portion 23 and restricts the removal of the spherical seat 6 a from the receiving portion 22, and the shoe 20 is provided on the inner periphery of the receiving portion 22. A piston slide portion 30 is provided as a slide portion that is provided and slidably contacts the spherical seat 6 a of the piston 6, and a first locking portion 40 is provided between the main body portion 23 of the receiving portion 22 and the piston slide portion 30.

In this configuration, the piston slide portion 30 is provided on the inner periphery of the receiving portion 22 where the shoe 20 and the piston 6 are in sliding contact. The first locking portion 40 is provided between the piston slide portion 30 and the main body portion 23 of the receiving portion 22 and restricts relative rotation between the piston slide portion 30 and the shoe main body portion 21. As described above, since the first locking portion 40 is provided not on the reduced diameter portion 24 but on the main body portion 23, the first locking portion is formed when forming a reduced diameter portion 24 by reducing a part of the main body portion 23. 40 is not deformed. Therefore, it is possible to prevent the durability of the first locking portion 40 from being lowered.

In the piston pump motor 100, the shoe body 21 has a flat plate portion 25 that is formed in a disc shape and faces the swash plate 8, and the shoe 20 covers the outer peripheral surface 25 b of the flat plate portion 25. The swash plate slide portion 31 as a slide portion provided in the portion 25 and slidably contacting the swash plate 8 is provided, and the second locking portion 50 is provided between the outer peripheral surface 25 b of the flat plate portion 25 and the swash plate slide portion 31. It is done.

In this configuration, the swash plate slide portion 31 is provided on the flat plate portion 25 where the shoe 20 and the swash plate 8 are in sliding contact. The second locking portion 50 is provided between the swash plate slide portion 31 and the outer peripheral surface 25 b of the flat plate portion 25. For this reason, the second locking portion 50 restricts relative rotation between the swash plate slide portion 31 and the shoe 20 body, and prevents the swash plate slide portion 31 from falling off the shoe 20 body.

Further, the piston pump / motor 100 is provided with projections (first projection 42, second projection 52) on slides (piston slide 30, swash plate slide 31), and recesses (first recess). 41, the second recess 51) is provided in the shoe main body 21.

In this configuration, the protrusions (first protrusion 42, second protrusion 52) can be formed by filling the recesses (first recess 41, second recess 51) with resin. Therefore, the projections (first projection 42, second projection 52) are formed more easily than when the shoe body 21 is processed to provide projections (first projection 42, second projection 52). be able to.

Further, in the piston pump / motor 100, the depressions (the first depression 41 and the second depression 51) are formed by curved surfaces.

According to this configuration, since the right-angled corners are not formed in the depressions (the first depression 41 and the second depression 51), the resin is filled into the depressions (the first depression 41 and the second depression 51). In addition, the stress concentration on the corners is prevented and the durability of the recesses (first recess 41, second recess 51) and protrusions (first protrusion 42, second protrusion 52) is improved. Can be improved.

The embodiment of the present invention has been described above. However, the above embodiment is merely one example of application of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

This application claims priority based on Japanese Patent Application No. 2015-183222 filed with the Japan Patent Office on September 16, 2015, the entire contents of which are incorporated herein by reference.

Claims

A hydraulic rotating machine,
A cylinder block connected with a shaft and rotating together with the shaft;
A plurality of cylinders formed in the cylinder block and arranged at predetermined intervals in the circumferential direction of the shaft;
A piston slidably inserted into the cylinder and defining a volume chamber inside the cylinder;
A shoe that is rotatably connected to the tip of the piston and is in sliding contact with the tip;
A swash plate with which the shoe slides,
The shoe is
A resin-made slide portion provided on at least one of a portion slidingly contacting the piston and a portion slidingly contacting the swash plate;
A shoe body part to which the slide part is attached;
A locking portion that is provided between the shoe main body portion and the slide portion and restricts relative rotation between the shoe main body portion and the slide portion;
The locking portion is
A recess formed in one of the shoe body and the slide;
A hydraulic rotary machine having a protrusion formed on the other of the shoe main body and the slide and engaging with the recess.
The hydraulic rotating machine according to claim 1,
The piston has a spherical seat formed at the tip,
The shoe main body has a receiving portion for receiving the spherical seat of the piston,
The receiving portion is
The main body,
A diameter-reduced part that is reduced in diameter from the main body part and restricts removal of the spherical seat from the receiving part,
The shoe has a piston slide portion as the slide portion provided on the inner periphery of the receiving portion and in sliding contact with the spherical seat of the piston,
The locking portion is a hydraulic rotating machine provided between the main body portion of the receiving portion and the piston slide portion.
The hydraulic rotating machine according to claim 1,
The shoe main body portion has a flat plate portion formed in a disc shape and facing the swash plate,
The shoe has a swash plate slide portion as the slide portion that is provided on the flat plate portion so as to cover the outer peripheral surface of the flat plate portion and is in sliding contact with the swash plate,
The locking portion is a hydraulic rotating machine provided between the outer peripheral surface of the flat plate portion and the swash plate slide portion.
The hydraulic rotating machine according to claim 1,
The recess is provided in the shoe main body,
The protrusion is a hydraulic rotating machine provided on the slide portion.
The hydraulic rotating machine according to claim 1,
The recess is a hydraulic rotating machine formed by a curved surface.