JPS60230572A - Piston pump or motor - Google Patents

Abstract

PURPOSE:To simplify the feed and discharge structure for a hydraulic fluid, by installing a torque plate in a fixed shaft piercing through a rotatable casing, while setting up a cylinder block having plural pistons inside the casing, in case of a bent axis type axial piston or motor. CONSTITUTION:A torque plate 7 is fitted with a spline in a fixed shaft 4 where a casing 1 consisting of a cylindrical front cover part 2 and a rear cover part to be coupled with an opening part at the rear end of the former is pierced through and supported with a bearing. A cylinder block 8 being free of rotation around an inclined shaft center L tilted as far as a constant angle theta to a shaft center M of the shaft 4 is set up in the rearward of this torque plate 7. And, each piston 12 is fitted in plural cylinder holes 11 in parallel with the inclined shaft center L formed in the cylinder block 8, and a spherical outward end 12a of the piston 12 is pivotally supported on the torque plate 7. In addition, a pump chamber 18 inside each cylinder hole 11 is connected to each of in- and outflow ports 21 and 22 via a distributor 25.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a piston-type pump or motor of an oblique shaft type that can be used in various fields of hydraulic equipment.

(b) Prior art■ Second, pumps or motors (meaning fluid machines that function as pumps when rotary power is applied and function as motors when high-pressure hydraulic oil is input) used in the field of hydraulic equipment can be broadly divided into There are gear-type, vane-type, and piston-type pumps; however, recently, there has been a trend toward using piston-type pumps or motors instead of gear-type pumps or motors or vane-type pumps or motors. This is because piston-type pumps or motors have the advantages of being highly efficient, allowing the size to be changed steplessly, and being suitable for high pressure applications. Highly efficient oblique shaft type piston pumps or motors are attracting attention.

However, as is well known, in conventional oblique shaft type pumps or motors, the shaft is cantileverly supported on the casing, making it difficult to supply and discharge working fluid from the shaft side into the cylinder block. There are circumstances. Therefore, there are only types in which the casing is fixed and the shaft rotates.

However, when such a hydraulic machine is used as a motor to drive the running wheels of a vehicle or a winch drum, or as a belt-driven pump or motor, it is necessary to fix the shaft and rotate the casing. A more compact design is possible. Therefore, there is a desire for a highly efficient diagonal shaft pump or motor with a casing rotation type.

(c) Purpose The present invention was made with attention to such circumstances,
The working fluid can be supplied and discharged from the shaft side into the cylinder block easily and reliably, and even when a large load is applied to the casing, the bearing part does not become large, and the shaft can be fixed. It is an object of the present invention to provide a diagonal shaft type pump or motor that can be widely used in various applications as a casing rotation system in which the casing is rotated.

(D) Structure In order to achieve the above object, the present invention provides a casing that is rotatable around an axis, a torque plate disposed within the casing with the axes aligned, and an axis that is aligned with the axis of the torque plate. A cylinder block is provided around the intersecting inclined axes and has a plurality of cylinder holes parallel to the inclined axes and opened toward the torque plate, and a cylinder block is slidably fitted into each of the cylinder holes of the cylinder block, and the outer cylinder is slidably fitted into each cylinder hole of the cylinder block. a plurality of pistons whose opposite ends are pivotally supported by the torque plate; a pump chamber formed by the inner end of the piston Q and the cylinder hole; a fixed shaft that supports the plate in a non-rotatable manner and rotatably supports the casing on both sides of its penetration portion; a pair of inflow and outflow ports for guiding hydraulic fluid provided within the fixed shaft; and a pair of inflow and outflow ports provided in the casing. a pair of connection ports that communicate with a pump chamber whose volume increases and a pump chamber whose volume decreases as the casing rotates; and a pair of connection ports that are provided between the casing and the fixed shaft and correspond to the respective connection ports. It is characterized in that it is equipped with a distributor that is always connected to each of the inflow and outflow ports.

(e) Examples Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic vertical sectional view of a piston pump or motor according to the present invention, and numeral 1 in the figure is a casing. The casing 1 consists of a cylindrical front cover part 2 and a cover part 3 which is liquid-tightly attached to the rear end opening of the front cover part 2. A fixed shaft 4 is provided passing through the casing 1. The fixed shaft 4 is
It is for rotatably supporting the casing 1 around the axis M, and rotatably supports both end portions of the casing l via a first bearing 5 and a second bearing 6 provided near both ends. are doing. Then, one end 4a thereof is extended to the outside through an opening 2a provided in the front cover part 2, and the other end 4b is extended to the outside through an opening 3a provided in the rear cover part 3. There is.

Further, a spline groove engraved portion 4C is provided at a portion of the fixed shaft 4 located inside the casing 1, and a disk-shaped torque plate 7 is fitted and fixed to this spline groove engraved portion 4C.

A cylinder block 8 is disposed behind the torque plate 7. The cylinder block 8 is a thick cylindrical body provided around an inclined axis that is inclined by a certain angle θ with respect to the axis M of the torque plate 7 and the fixed shaft 4. , the rear end surface is placed in sliding contact with a valve surface 9 formed on the rear cover part 3. Further, the cylinder block 8 is provided with a plurality of cylinder holes 11 that are parallel to the tilt axis and open toward the torque plate 7 at equal angular intervals in the circumferential direction. A piston 12 is slidably fitted into each of these cylinder holes 11. The piston 12 is integrally formed with a piston main body 13 that fits into the cylindrical hole ll, and a mouth/end portion 14 that extends outward from the piston main body 13. 13 includes a piston ring 30 interposed between a fitting portion IO that fits into the inner periphery of the cylinder hole 11 with an appropriate gap (about 0.05 mm) and a presser plate 20. Then, the tip of the rod portion 14, that is,
The outer end 12a of the piston 12 is formed into a spherical shape,
This outer end 12a is pivotally supported by the torque plate 7. Specifically, the same number of spherical seats 15 as the pistons 12 are provided on one end surface of the torque plate 7 at equal angular intervals in the circumferential direction, and each of the spherical seats 15 has the same number of spherical seats 15 as the pistons 12. The outer end 12a is rotatably fitted. A piston retainer 16 prevents each piston 12 from coming off the torque plate 7. Further, a helical gear type rotation prevention mechanism 1 is provided between the torque plate 7 and the cylinder block 9.
7 is provided, and the rotation of the casing 1 also prevents scratches and
The ida block 8 is prevented from rotating. Also,
A pump chamber 18 is formed by the inner end 12b of each piston 12 and each cylinder hole 11. This pump chamber 18 opens at the rear end surface of the cylinder block 8 via a fluid passage 19.

In addition, a pair of inlet and outlet ports 21.2 are provided in the fixed shaft 4.
2 are provided, and connection ports 23 and 24 are opened in the valve surface 9 of the cylinder block 8. The connection port 23 is connected to the pump chamber 1 which exists in a region on the right side of FIG.
8, and the other connection port 24 is located in an area on the left side of the virtual dividing plane N! They are each formed in a semicircular arc shape so as to communicate with the pump chamber 18 located in (2). Then, the inflow/outflow port 21 is connected to the connection port 23.
In addition, the inflow/outflow port 22 is always connected to the connection port 24 via a distributor 25. That is, this distributor 25 is connected to the fixed shaft 4
A pair of annular grooves 26.27 are provided on the outer periphery of the rear cover 3 of the casing l, and a pair of annular grooves 26.27 are provided on the inner periphery of the rear cover 3 of the casing l.
Communication passages 28 and 29 are opened to constantly communicate with each of 27, and each of these communication passages 28 and 29 is about to be connected to each corresponding connection port 23 and 24, respectively.

This piston pump or motor has a fitting length t of the piston 12 with respect to the cylinder hole 11;
The inclination angle θ of the inclination axis is both set to a small value, specifically, the fitting length is set to a value of about 1.0 mm, and the inclination angle θ is set to 15″ or less, preferably 1.
It is set to about 0°.

Further, the surface 32 of the torque plate 7 on the side opposite to the cylinder block is brought into close contact with the pressure receiving surface 33 provided on the casing l, and a pressure pocket 34 into which the working fluid in the pump chamber 18 is introduced between these surfaces 32 and 33. , and is configured such that the axial force of the working fluid in the pressure pocket 34 pressing the torque plate 7 and the axial force acting on the torque plate 7 from the piston 12 side are approximately balanced. There is. Specifically, the torque plate 7
A pressure pocket 35 is formed in each spherical seat 15 of the piston 12, and a pressure fluid introduction passage 36 is provided at the axial center of the piston 12, and a part of the working fluid in the pump chamber is contained within the pressure pocket 35. We are trying to introduce. Further, the portion of the other end surface of the torque plate 7 corresponding to each of the spherical seats 15 is made to protrude in a circular shape, and the protruding surface 32 thereof is brought into close contact with a pressure receiving surface 33 provided on the front cover part 2.

Further, a pressure pocket 34 having a shape as shown in FIG. 4 is provided on the protruding surface 32, and a part of the hydraulic fluid in the pump chamber 18 is introduced into the pressure pocket 34 through a hydraulic fluid introduction passage 37. There is. and the pressure pocket 3
The resultant force of the axial pressure PL of the working fluid in the pressure pocket 35 and the resultant force of the axial pressure P2 of the working fluid in the pressure pocket 35 are approximately balanced. Note that 38 is a spring for keeping the torque plate 7 in constant contact with the pressure receiving surface 33 and pressing the cylinder block 8 against the valve surface 9 of the casing l. 1. In FIG. 1, for convenience of explanation, the arrangement phases of the cylinder hole 11, connection ports 23, 24, etc. are slightly different from the actual arrangement. Please refer to FIGS. 3 and 4 for their correct location.

Further, in FIG. 2, numeral 39 indicates a drain port.

Next, the operation of this embodiment will be explained.

High-pressure hydraulic fluid is caused to flow into the casing 1 through an inlet/outlet port 21 provided in the fixed shaft 4. Therefore, this working fluid flows into the annular groove 26 of the distributor 25, is roughly introduced into the connection boat 23 via the communication path 28, and from this connection boat 23 into the pump chamber 18 present in the first region T. be guided. The pressure inside the pump chamber 18 into which the hydraulic fluid has been introduced becomes high, and the pressure presses the corresponding piston 2, causing the torque plate 7 to rotate clockwise in FIG. 3. However, since the torque plate 7 is non-rotatably supported by the fixed shaft 4, the pulp surface 9 is pushed back, and the rear case 3 is moved counterclockwise in FIG. ). In this way, as the casing l rotates, the connection boat 23 also rotates clockwise, and the first
The area engineering also rotates and moves accordingly. Therefore, if the working fluid continues to be supplied into the casing 1 through the inflow/outflow port 21, the pump chamber 18 existing in the first region
The working fluid sequentially flows into the pump chamber 18 to increase the volume of the pump chamber 18. On the other hand, the pump chamber 18 existing in the second region II
The volume decreases as the casing l rotates. Due to this reduction in volume, the hydraulic fluid is discharged from the inside of the pump chamber 18 to the connection boat 24. The thus discharged hydraulic fluid flows from the connection boat 24 through the communication path 29 into the annular groove 27 of the distributor 25, and is further discharged to the outside of the casing l through the inflow/outflow boat 22.

Note that when the hydraulic fluid is allowed to flow in from the inflow/outflow boat 22, the operation is reversed to that described above, and the casing 1 rotates in the opposite direction.

In this way, the casing 1 rotates and functions as a motor. In this case, the fixed shaft 4 is provided so as to pass through the torque plate 7 and the cylinder block 8. Bearing casing 1 on both sides 5
．． 6, a large load is not applied to the bearing unlike when the shaft is supported cantileverly by the casing. Therefore, even if a method is adopted in which the shaft 4 is fixed and the casing l is rotated, it is difficult to support and rotate the central bearing center Mite (r), l, y, and t) 11. It is something that can be done.

Moreover, the fixed shaft 4 is provided to penetrate through the torque plate 7 and the cylinder block 8, and a distributor 25 is provided between the fixed shaft 4 and the casing 1.
and a connecting boat 23.2 provided on said casing l.
4 and outflow/inflow boats 21 and 22 bored in the fixed shaft 4
Since the fixed shaft 4 is always in communication with the
The hydraulic fluid can be supplied and discharged from the side into the cylinder block 8 easily and reliably. Therefore, such a motor can be suitable as a traveling hydraulic motor if a tire can be attached to the outer circumference of the casing l. Moreover, by making the casing 1 into a drum, it can be used as a winch. Furthermore, if a pulley portion on which a belt can be hung is formed on the outer periphery of the casing l, it can be used as a belt-driven pump or motor.

Furthermore, the inclination accuracy θ of the piston 12 and the piston 12
Since the fitting length t with respect to the cylinder block hole 11 is both set to a small value, the structure can be simplified without causing the inconvenience that smoother operation of engagement between the piston and the cylinder hole is hindered. In addition, it is possible to achieve a reduction in size and weight.

Moreover, the axial force of the hydraulic pressure generated during operation is received by the reaction force of the valve surface 9 and pressure receiving surface 33 of the casing 1, and the axial force acting on the cylinder block 8 and torque plate 7 is Hydraulic pressure is balanced. Therefore, there is no need to use a thrust bearing or a large bearing that serves both thrust and radial functions, and from this point of view as well, it is possible to promote downsizing and weight reduction, and it is also possible to achieve lower costs and longer life.

Note that the present invention is of course not limited to the above-mentioned embodiments, and the fixed shaft may not pass through the casing.

Further, the distributor is not limited to the one in the embodiment described above, and may be one that constantly connects each connection port to each corresponding inflow/outflow boat.

In addition, various modifications can be made without departing from the spirit of the present invention.

(f) Effects Since the present invention has the above-described configuration, the working fluid can be supplied and discharged from the shaft side into the cylinder block easily and reliably.

The oblique shaft type does not increase the size of the bearing even when a large load is applied to the casing, and allows the casing to rotate while the shaft is fixed.The slanted shaft type can be used in a wide variety of applications as a casing rotation system. pump or motor.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view, FIG. 2 is an enlarged view of IT in FIG. The diagram shows IV in Figure 1.
-IT line partial sectional view, and FIG. 5 is a partially enlarged sectional view of the torque plate. l@...Casing 4 a a m fixed shaft 5・φ-i
t bearing 6...Second bearing 7...φtorque plate 8φΦ・cylinder block 11・e・cylinder hole 12・φ・piston 18・fist・
Pump room 21.22#/e Outflow/inflow boat 23, 24...I concubine port 1r3
1-...Bearing 25, 11φ Distributor 26.2711 轡・Annular groove Lφ... Inclined shaft center M... Axis center Agent Patent attorney Hiroshi Akazawa Figure 1 α' Figure 2

Claims (1)

[Scope of Claims] A casing rotatable around an axis, a torque plate disposed within the casing so that the axes coincide with each other, and a torque plate disposed around an inclined axis that intersects with the axis of the torque plate,
A cylinder block has a plurality of cylinder holes parallel to the inclined axis and opens toward the torque plate, and the cylinder block is slidably fitted into each cylinder hole of the cylinder block, and its outer end is pivoted to the torque plate. a plurality of supported pistons; a pump chamber formed by the inner end of the pistons and the cylinder hole; A fixed shaft that rotatably supports the casing with a bearing on both sides of the penetration part, a pair of inflow and outflow ports provided in the fixed shaft for guiding hydraulic fluid, and a pair of inflow and outflow ports provided in the casing that increase the volume as the casing rotates. A pair of connection ports are provided between the casing and the fixed shaft, each communicating with a pump chamber where the volume increases and a pump chamber where the volume decreases, respectively. A piston pump or a motor, each of which is characterized in that it is equipped with a distributor that is always connected.