JPH0560055A - Radial piston type liquid pressure rotating machine - Google Patents

Abstract

PURPOSE:To prevent removal of a ball from a shoe by a tensile force generated when a rotor is rotated at a high speed by caulking and fixing the shoe to the ball for increasing an engagement force of the ball with the shoe; CONSTITUTION:A shoe 31 is fixed to a support table 16, a shaft part 31A of the shoe 31 is fitted in to be engaged with an engagement hole 12A of a ball 12, a caulking jig 34 is inserted into an insertion hole 32, it is pushed axially under a ressure to deform a caulked part 33 elastically, and the caulked part 33 contacts each pushed surface part 34D. Because each pushed surface part 34D is formed for its caulking width to be enlarged from the forward end side to a middle part gradually, the caulking length and caulking width of the caulked part 33 are both increased gradually to push and crush a forward end of the caulked part diametrically outward thereby it is caulked and fixed to the ball 12 locally at two positions facing each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radial piston type hydraulic rotary machine suitable for use as, for example, a hydraulic pump or hydraulic motor.

[0002]

13 to 17 show an example of a radial piston type hydraulic rotary machine of the prior art as a radial piston type hydraulic rotary machine of the prior art.

In the drawing, reference numeral 1 denotes a casing, which is composed of a bottomed cylindrical casing body 2 and a disc-shaped front casing 3 provided by covering the opening side of the casing body 2. It is formed in a tubular shape. Further, the casing body 2 is integrally formed with an annular bottom portion 2A so as to project from the outer peripheral side of the bottom portion 2A, and the cylindrical portion 2B that abuts the front casing 3 and the entire circumference of the inner peripheral side of the cylindrical portion 2B. And the cam surface 2C formed over.

Reference numeral 4 denotes a control pin as a support shaft integrally formed to project from the front casing 3 toward the bottom portion 2A of the casing body 2, and the axis O--O of the control pin 4 is
It is eccentric by a predetermined dimension d from the axis O1 -O1 of the cam surface 2C. Further, as shown in FIG. 14, the control pin 4 has a pair of intake / exhaust passages 5, which have a semicircular cross section and open to the peripheral surface.
6 is formed in the axial direction.

Reference numeral 7 denotes a thick disk-shaped rotor rotatably provided on the control pin 4, and a pin into which the control pin 4 is fitted is located in the center of the front surface (front casing 3 side) of the rotor 7. A fitting hole 7A is formed, and a coupling 7B into which a rotary shaft (not shown) of a driving means such as an electric motor is inserted is integrally formed on the back side of the rotor 7 so as to project in the axial direction. .. Further, since the axis O-O of the rotor 7 is eccentric with the axis O1-O1 of the cam surface 2C, a crescent-shaped eccentric space is provided between the outer peripheral side of the rotor 7 and the cam surface 2C of the casing body 2. 8 is formed. Then, the rotor 7 is
It rotates around the axis O-O of the control pin 4.

.. indicate a plurality of cylinders radially formed on the rotor 7 at predetermined angular intervals in the circumferential direction, and each of the cylinders 9 is formed when the rotor 7 rotates.
Port 1 bored on the bottom side (center side of rotor 7)
, 0, 10, ... Through intermittent communication with the intake and exhaust passages 5, 6.

Reference numerals 11, 11, ... Denote reciprocating pistons provided in the respective cylinders 9, and a concave spherical mounting portion 11A is formed on the inner peripheral surface of the piston 11 as shown in FIG. ing. The reference numerals 12, 12, ... Depict substantially spherical balls that are press-fitted into the mounting portions 11A of the pistons 11 and are swingably provided and have flat surfaces on both axial ends. A fitting hole 12A into which a shaft portion 13A of the shoe 13 described later is fitted is bored in the axial direction.

.. indicate a plurality of shoes provided circumferentially spaced between each piston 11 and the cam surface 2C of the casing body 2, and each shoe 13 has one end on each ball. The sliding portion is a shaft portion 13A that is press-fitted and fitted into the fitting hole 12A of the sliding member 12, and the other end side is slidably provided on the cam surface 2C of the casing body 2 via the cylindrical guides 14 and 14. It is 13B. In addition, an oil passage 13C having a small diameter in the axial direction is formed in each shoe 13 from the shaft portion 13A to the sliding portion 13B, and the other end side of the oil passage 13C is partially enlarged in diameter to form a positioning hole 13D. ing. The shoes 13 reciprocate in the cylinder 9 through the balls 12 while sliding on the cam surface 2C of the casing body 2 in the circumferential direction as the rotor 7 rotates. Is.

Reference numeral 15 denotes a seal member provided between the outer peripheral side of the coupling 7B of the rotor 7 and the bottom portion 2A of the casing body 2. The seal member 15 prevents the oil liquid in the casing body 2 from leaking to the outside. Is being prevented.

Further, in FIG. 16, 16 is a shoe 13.
2 shows a support base used when assembling, and a positioning pin 16A which is fitted into the positioning hole 13D of the shoe 13 is provided at the center of the support base 16 so as to project. Reference numeral 17 is a press-fitting jig for press-fitting the shaft portion 13A of the shoe 13 into the fitting hole 12A of the ball 12.

The radial piston type hydraulic rotary machine according to the prior art has the above-mentioned construction, and then the shoe 1
The assembling method such as 3 will be described.

First, the positioning pin 16A of the support base 16 is inserted into the positioning hole 13D of the shoe 13 to fix the shoe 13 on the support base 16, and then the shaft portion 1 of the shoe 13 is attached.
Place the ball 12 on 3A. Then, when the ball 12 is strongly pressed in the direction of the arrow by the press-fitting jig 17 as shown in FIG. 16, the fitting hole 1 of the ball 12 as shown in FIG.
The shaft portion 13A of the shoe 13, which has a diameter slightly larger than that of the fitting hole 12A, is press-fitted and fitted into 2A. As a result, the ball 12 and the shoe 13 are integrally fixed by the frictional force of the contact surface between the fitting hole 12A and the shaft portion 13A.

Next, the operation of the radial piston type hydraulic rotary machine assembled as described above when used as a hydraulic pump will be described.

First, when the rotary shaft is inserted into the coupling 7B of the rotor 7 and the rotary shaft is rotationally driven in the direction of arrow A by the drive means, the rotor 7 rotates about the axis O--O, As a result, each cylinder 9 intermittently communicates with each of the intake and exhaust passages 5 and 6 via the port 10. Also, the rotor 7
The piston 11 and shoe 13 also rotate with the rotation of
The cam surface 2C on which the sliding portion 13B of the shoe 13 is slidably guided by each guide 14 has its axis O1-O1 eccentric from the axis O-O of the control pin 4 by the dimension d, so that the rotor 7 is The piston 11 reciprocates once inside the cylinder 9 while rotating.

In the state shown in FIG. 14, the cylinder 9 is connected to the intake / exhaust passage 5 through the port 10 while the piston 11 projects from the center to the lower side of the hydraulic rotating machine for a half rotation. This is a suction stroke in which the oil liquid is sucked into the cylinder 9 from the passage 5 through the passage. On the other hand, while the piston 11 from the center to the upper side of the hydraulic rotating machine enters into the cylinder 9 for half a rotation, the inside of the cylinder 9 communicates with the intake / exhaust passage 6 via the port 10, and the oil liquid inside the cylinder 9 Becomes a discharge stroke in which it is pressurized by the piston 11 and discharged into the passage 6. By repeating the suction stroke and the discharge stroke, the pump action is continuously performed.

[0016]

By the way, in the radial piston type hydraulic rotary machine according to the above-mentioned prior art, in the suction stroke in which the piston 11 projects from the inside of the cylinder 9, the volume of the cylinder 9 is increased as the piston 11 moves. Expand, and a negative pressure is generated in the cylinder 9, so that the negative pressure causes a pulling force on the piston 11 in the axial direction OO of the rotor 7. Here, when the rotor 7 rotates at a low speed, the speed at which the volume of the cylinder 9 expands is also slow, so this tensile force is relatively small, but when the rotor 7 rotates at a high speed, the volume expansion speed of the cylinder 9 also becomes faster. A strong pulling force acts on the piston 11. Since the sliding portion 13B of the shoe 13 is guided by the cam surface 2C of the casing body 2 by each guide 14, this pulling force mainly causes the ball 12 to reach the shoe 13.
It acts as a pulling force from the shaft portion 13A.

However, the ball 12 is provided by being press-fitted into the shoe 13, and both are integrally fixed only by the frictional force of the contact surface between the fitting hole 12A of the ball 12 and the shaft portion 13A of the shoe 13. It's just that. Therefore, when the pulling force generated when the rotor 7 rotates at a high speed exceeds this frictional force, the ball 12 is pulled out from the shoe 13 and disassembled, and the radial piston type hydraulic rotating machine is damaged. is there.

The present invention has been made in view of the above-mentioned problems of the prior art. By fixing the shoe to the ball by caulking, the engaging force between the ball and the shoe is enhanced, and the ball is pulled by the pulling force generated when the rotor rotates at a high speed. It is an object of the present invention to provide a radial piston type hydraulic rotating machine capable of preventing the gear from being pulled out from the shoe.

[0019]

In order to solve the above-mentioned problems, the feature of the structure adopted by the present invention is that after the shaft portion of the shoe is fitted into the ball, the shaft portion is caulked and fixed to the ball. It is in.

Further, it is preferable that the shaft portion of the shoe is caulked and fixed to the ball by a caulking jig in which an arcuate pressing surface portion whose caulking width gradually increases from the tip end side toward the middle portion is formed.

[0021]

After the shaft portion of the shoe is press-fitted into the ball, the shaft portion is caulked and fixed to the ball. Therefore, the friction force of the contact surface between the ball and the shaft portion of the shoe and the caulking cause the ball to come into contact with the ball. The shoe can be firmly fixed.

Further, if a caulking jig having an arcuate pressing surface portion in which the caulking width is gradually widened from the tip side toward the middle portion is used, the pressing surface portion allows the caulking width of the caulking portion of the shaft portion to be It can be increased according to the pressing force at the time of crimping, and cracks can be prevented from occurring at the crimped portion.

[0023]

Embodiments of the present invention will be described below with reference to FIGS. In the embodiment, the same components as those of the prior art shown in FIGS. 13 to 17 described above are designated by the same reference numerals, and the description thereof will be omitted.

First, FIGS. 1 to 6 show a first embodiment of the present invention.

In the figure, reference numeral 21 designates a shoe (only one is shown) according to the present embodiment provided between the piston 11 and the cam surface 2C of the casing main body 2. The shoe 21 is the shoe 13 according to the above-mentioned prior art. The shaft portion 2 whose one end side is press-fitted into the fitting hole 12A of each ball 12 in the same manner as
1A, and the other end of the sliding portion 2 is slidably provided on the cam surface 2C of the casing body 2 via each guide 14.
1B, an oil passage 21C and a positioning hole 21D are formed. However, on the tip end side of the shaft portion 21A of the shoe 21, an insertion hole 22 into which a projection 23B of a caulking jig 24 described later is inserted is formed by expanding the oil passage 21C, and the outer peripheral side of the insertion hole 22 is formed. As shown in FIG. 4, a caulking portion 23, which is caulked and fixed by a caulking jig 24, is integrally formed therewith.

Reference numeral 24 denotes a caulking jig for caulking and fixing the shoe 21 to the ball 12, and the caulking jig 24 is
As shown in FIG. 2, a support rod 24A whose tip side is formed in a substantially conical shape, and whose base end side is connected to a drive source (not shown) of a caulking device, and the tip end side of the support rod 24A have a width at the center thereof. A pair of flat surface portions 24C, 24C that are formed by being cut out by a length dimension L in the axial direction so as to face each other so as to leave the projection 24B having the dimension W, and the outer periphery of the projection 24B across the flat surface portions 24C. It is composed of a pair of pressing surface portions 24D, 24D formed in an arc shape on the side.

Next, an assembling method of assembling the shoe 21 to the ball 12 will be described with reference to FIGS. 3 to 6.

First, in the press-fitting process shown in FIG.
Positioning pin 1 of the support 16 in the positioning hole 21D of 1
6A is inserted and supported, and the shoe 21 is supported on the support base 16, and then the ball 12 is placed on the shaft portion 21A of the shoe 21.
By strongly pressing the ball 12 in the direction of the arrow by the press-fitting jig 17, the shaft portion 21A of the shoe 21 is press-fitted and fitted into the fitting hole 12A of the ball 12.

Next, in the caulking process shown in FIG. 4, after the press-fitting jig 17 is removed, the caulking jig 24 is also shown as shown in FIG.
The protrusion 24B is inserted into the insertion hole 22 of the shoe 21 and pressed in the direction of the arrow. As a result, the caulking portion 23 is plastically deformed at the portion pressed by each pressing surface portion 24D of the caulking jig 24, and the caulking portion 23 and each pressing surface portion 2 of the caulking jig 24 are deformed.
4D gradually comes into surface contact with a caulking width of width W from the line contact. And further caulking jig 2
When 4 is pressed in the axial direction, the caulking length of the caulking portion 23 increases, and as shown in FIG. 6, the tip of the caulking portion 23 protrudes outward in the radial direction and hits the ball 12 at two points facing each other. Caulking fixing surface portions 23A, 23 that are locally caulked and fixed
It becomes A.

The radial piston type hydraulic rotary machine according to this embodiment has the above-mentioned structure, and its basic operation is not different from that of the prior art.

In this embodiment, however, after the ball 12 is press-fitted into the shaft portion 21A of the shoe 21, the caulking portion 23 of the shoe 21 is caulked and fixed to the ball 12 by the caulking jig 24. 21 and the ball 12 can be firmly fixed by the frictional force of the contact surface due to the press-fitting and the caulking portion 23. As a result, when the rotor 7 rotates at high speed, the balls 12 and the like are pulled toward the center side of the rotor 7 by the pulling force generated in the cylinder 9, and the balls 12 are pulled out from the shaft portion 21A of the shoe 21. The ball 12
The shoe 21 and the shoe 21 can be prevented from disassembling, and the reliability and life of the radial piston hydraulic rotary machine can be significantly improved. Further, since the caulking jig 24 is formed with a pair of flat surface portions 24C, 24C, each pressing surface portion 24
Only D is brought into contact with the caulking portion 23 so that each caulking fixing surface portion 2
3A can be formed, the pressure of each pressing surface portion 24D can be increased, and caulking and fixing can be efficiently performed, and the caulking device can be downsized.

Next, FIGS. 7 to 12 show a second embodiment of the present invention. The feature of this embodiment is that an arc-shaped pressing surface portion whose caulking width gradually increases from the tip side toward the middle portion is provided. The shoe is fixed to the ball by caulking using the formed caulking jig.

In the figure, 31 indicates a shoe according to this embodiment, and the shoe 31 has a fitting hole 12 for a ball 12 on one end side, which is substantially the same as the shoe 21 described in the first embodiment.
The sliding portion 3 is a shaft portion 31A that is press-fitted into A, and the other end side is slidably guided on the cam surface 2C of the casing body 2.
1B, an oil passage 31C and a positioning hole 31D are formed, and an insertion hole 32 and a caulking portion 33 are integrally formed on the tip side of the shaft portion 31A. However, the shoe 31
Is caulked and fixed to the ball 12 by a caulking jig 34 described later.

That is, reference numeral 34 denotes a caulking jig according to this embodiment. The caulking jig 34 has a support rod 34A having a substantially conical tip side as shown in FIG. 8 and a tip side of the support rod 34A. A pair of flat surface portions 3 which are formed in a wedge shape so as to face each other so as to leave a protrusion 34B having a predetermined angle α and are obliquely cut in the axial direction by a length dimension L1.
4C, 34C and the projection 3 extending between the flat surface portions 34C.
4B is formed in an arc shape on the outer peripheral side, and is composed of a pair of pressing surface portions 34D, 34D whose width dimension gradually increases from the front end side toward the intermediate portion at a predetermined angle α.

Next, an assembling method of assembling the shoe 31 to the ball 12 will be described with reference to FIGS. 9 to 12.

First, in the press-fitting step shown in FIG.
Similar to the press-fitting process described in the above embodiment, the positioning pin 16A of the support 16 is inserted into the positioning hole 31D of the shoe 31.
After inserting the shoe 31 and supporting the shoe 31 on the support base 16,
The ball 12 is placed on the shaft portion 31A of the shoe 31, and the ball 12 is strongly pressed by the press-fitting jig 17 in the direction of the arrow so that the shoe 3 is inserted into the fitting hole 12A of the ball 12.
The first shaft portion 31A is press-fitted and fitted.

Next, in the caulking step shown in FIG. 10, after the press-fitting jig 17 is removed, the protrusion 34B of the caulking jig 34 is inserted into the insertion hole 32 of the shoe 31 as shown in FIG. Press in the direction. As a result, the portion of the caulking portion 33 that is pressed by the pressing surface portions 34D of the caulking jig 34 is plastically deformed, and the caulking portion 33 and the pressing surface portions 34D of the caulking jig 34 gradually move from the line contact by a predetermined angle α. It comes into surface contact with a caulking width corresponding to. Since the pressing surface portions 34D are formed such that the crimping width gradually increases from the tip end side toward the intermediate portion, the crimping jig 3 is formed.
As 4 is pushed in the axial direction, both the caulking length and the caulking width of the caulking portion 33 increase, and as shown in FIG. 12, the tip of the caulking portion 33 is crushed outward in the radial direction, and Fan-shaped caulking fixing surface portions 33A and 33A are locally caulked and fixed at two opposing locations.

Thus, in this embodiment having such a configuration, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. However, in particular, in this embodiment, a pair of pressing surface portions 34D, 34D are formed on the tip side of the caulking jig 34, in which the caulking width is gradually increased from the tip side toward the intermediate portion according to the predetermined angle α, Since the shoe 31 is caulked and fixed to the ball 12 by the caulking jig 34, the caulking portion 3 is increased in accordance with an increase in the pressing force of the caulking jig 34.
3 can be crushed in the circumferential direction to form each caulking fixing surface portion 33A, and the caulking width can be effectively increased. As a result, it is possible to effectively prevent the caulking portion 33 from being largely deformed radially outward, to prevent the caulking portion 33 from being defective in caulking such as cracking, and to securely engage the shoe 31 with the ball 12. Therefore, the caulking work can be performed efficiently and stably.

In each of the embodiments described above, the case where the pintle type hydraulic rotary machine is used as the radial piston hydraulic rotary machine for the hydraulic pump has been described as an example, but the present invention is not limited to this. For example, a so-called valve plate type liquid is provided between the casing 1 and the side surface of the rotor 7, which is provided with a valve plate having an eyebrow suction / discharge passage formed therein, and which sucks and discharges the oil liquid into the cylinder through the eyebrow suction / discharge passage. It can be used as a pressure rotary machine and also as a hydraulic motor.

[0040]

As described in detail above, according to the present invention, after the shaft portion of the shoe is press-fitted into the ball and the shaft portion is caulked to the ball, the shoe and the ball are separated. The frictional force of the contact surface between the ball and the shaft of the shoe and the caulking can firmly fix the ball. As a result, it is possible to reliably prevent the ball or the like from being pulled toward the center side of the rotor by the pulling force generated in the cylinder when the rotor rotates at high speed, and the ball being pulled out from the shaft portion of the shoe. It is possible to effectively prevent the ball and the shoe from disassembling, and improve the reliability and life.

Further, since the caulking jig having the arcuate pressing surface portion in which the caulking width gradually increases from the tip side toward the middle portion is used, the shoe shaft portion is caulked and fixed to the ball. With the pressing surface portion, the crimping width of the crimping portion of the shaft portion can be increased according to the pressing force at the time of crimping. As a result, defective crimping such as cracking can be effectively prevented from occurring in the crimped portion, the ball and the shoe can be reliably engaged, and efficient and stable crimping work can be performed.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of essential parts showing a shoe or the like according to a first embodiment of the present invention in a completed state after a crimping step.

FIG. 2 is an external perspective view showing an enlarged main part of the caulking jig.

FIG. 3 is a longitudinal cross-sectional view of a main part showing a press-fitting step of press-fitting a ball into a shoe.

FIG. 4 is a vertical sectional view similar to FIG. 3, showing a caulking process for caulking and fixing a ball to a shoe.

FIG. 5 is a view showing a state in which a crimping jig is inserted into the shoe.
It is an expanded sectional view seen from the arrow V-V direction in the inside.

FIG. 6 is a plan view showing a state in which a ball is caulked and fixed to a shoe.

FIG. 7 is a vertical sectional view similar to FIG. 1, showing a shoe and the like according to a second embodiment of the present invention.

FIG. 8 is an external perspective view showing an enlarged main part of the caulking jig.

9 is a vertical sectional view similar to FIG. 3, showing a press-fitting step.

FIG. 10 is a vertical sectional view similar to FIG. 4, showing a caulking process.

11 is an enlarged cross-sectional view showing a state in which a crimping jig is inserted in the shoe, as seen from the direction of the arrow XI-XI in FIG.

FIG. 12 is a plan view showing a state where the ball is crimped and fixed to the shoe.

FIG. 13 is a vertical sectional view showing a radial piston type hydraulic rotating machine according to a conventional technique.

FIG. 14 is a sectional view taken along the line XIV-XIV in FIG.

FIG. 15 is a longitudinal sectional view of an essential part showing an enlarged shoe and the like.

FIG. 16 is a vertical cross-sectional view showing a press-fitting process of press-fitting a ball into a shoe.

FIG. 17 is a vertical sectional view showing a state after press-fitting and fitting.

[Explanation of symbols]

 1 Casing 2 Casing body 2C Cam surface 4 Control pin (supporting shaft) 7 Rotor 9 Cylinder 11 Piston 12 Ball 21, 31 Shoe 21A, 31A Shaft part 21B, 31B Sliding part 23, 33 Caulking part 24, 34 Caulking jig 24D , 34D Pressing surface

Claims (2)

[Claims] 1. A tubular casing having a cam surface formed on the inner peripheral side thereof, a support shaft provided so as to project from the casing with a predetermined eccentricity from the axial center of the cam surface, and rotatable on the support shaft. A plurality of cylinders formed in the radial direction of the rotor, a piston reciprocally movable in each cylinder, and a ball swingably provided in each piston, In a radial piston hydraulic rotating machine, one end of which serves as a shaft fitted to each ball, and the other end of which serves as a shoe that slides on the cam surface as the rotor rotates. In the radial piston type hydraulic rotating machine, the shoe has a shaft portion fitted to a ball and then the shaft portion is fixed to the ball by caulking. 2. The shaft portion of the shoe is caulked and fixed to a ball by a caulking jig in which an arcuate pressing surface portion whose caulking width gradually increases from the tip side toward the middle portion is formed. Item 1. A radial piston hydraulic rotating machine according to Item 1.