JPH07310647A - Piston pump or motor - Google Patents

Abstract

PURPOSE:To reduce the generation of heat and the generation of noise by a method wherein a flow part is arranged at a spline engagement tooth part between a torque plate and an annular cylinder block and when fluid leaking to the interior of the annular cylinder block passes through the spline engagement tooth part, cooling and lubrication of teeth are performed. CONSTITUTION:In an annular cylinder block 10 wherein the external end of a piston 9 fitted in each cylinder hole 10H of a piston pump is pivotally supported in the torque plate 6 side, an out spline tooth 10S is arranged at the end part of the extension cylinder of a cylinder part 10N extending in the direction of the external end of the piston. Meanwhile, an annular piston retainer 7 formed integrally with the torque plate 6 has an central hole in the inner peripheral surface of which in spline teeth 7S are formed and the two spline teeth 10S and 7S are engaged with each other with a gap therebetween. By passing oil, flowing in the direction of the external end of the piston and leaking to the interior of the cylinder block 10, through the gap at the engagement part, teeth are cooled and lubricated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston type pump or motor which can be used in various fields of fluid equipment (hydraulic equipment).

[0002]

2. Description of the Related Art A pump or a motor mainly used in the field of fluid equipment (a fluid machine that functions as a pump when rotational power is applied and functions as a motor when high-pressure liquid is input, but will be described below as an example of a pump). There are gear type and vane type, but recently, a piston type which is suitable for high pressure and has high efficiency is favorably used. Among them, the highly efficient diagonal shaft type piston pump is attracting attention.

In this oblique shaft type piston pump, a torque plate is integrally provided at an inner end of a rotating shaft supported by a casing through a bearing, and the outer end of each piston in the oblique axis direction is pivotally supported by the torque plate. It is of the form. However, in this type of pump, since the bearing mechanism of the rotary shaft becomes large due to the large thrust force applied to the torque plate, a new type of oblique shaft type piston pump has been proposed to solve this problem. That is, it is proposed by the applicant of the present application, and specifically, a patent application (Japanese Patent Laid-Open No. 63-246479).
No.) "Piston pump or motor". In this new type of oblique shaft type piston pump, the rotating shaft is supported by the casing through bearings, and the torque plate that pivotally supports the outer ends of the pistons in the oblique axis direction is
Separately from the rotating shaft, the pressure receiving surface formed on the inner wall of the casing is slidably contacted. Further, it is an oblique shaft type piston pump having a rotary shaft penetrating the annular cylinder block and the torque plate. By proposing such a new type, it is not necessary to upsize the mechanism for bearing the rotating shaft integrated with the torque plate.

By the way, in the case of the oblique shaft type piston pump of this kind, it is necessary that the cylinder block and the torque plate rotate synchronously, and therefore a mechanism for synchronizing both is installed. As the synchronizing mechanism, as shown in the above patent application, a gear (outward spline tooth) is provided on the torque plate side, and an internal gear (inward spline tooth) meshing with the gear is installed on the cylinder block side. There is. Rotation is synchronized by the meshing of both gears.

[0005]

In the case of this type of oblique shaft type piston pump, gear meshing as a mechanism for synchronous rotation causes a large noise when the gear meshing gap (backlash) is large. Tend. To eliminate this, the gap may be made small (extremely zero gap). However, in that case, heat generation due to friction of the tooth tips of the gears becomes large, and as a result, the tooth surface may be roughened and, in the worst case, a seizure phenomenon may occur. When such a phenomenon occurs, synchronous rotation is not guaranteed and the pump mechanism is destroyed.

On the other hand, the pressure liquid (pressure oil) due to the reciprocating motion of the piston flows out from the outlet hole formed on the casing side with which the annular cylinder block is rotationally slidably contacted. Oil leaks. The leaked oil flows not only outside the annular cylinder block but also inside. Lubrication and cooling of the gears of the synchronous mechanism can be expected by this leaked oil, but it is common to form a passage communicating with the low pressure side inlet in the casing so that the leaked oil can flow out to the outside to prevent it from being filled. Then, the leaked oil is discharged to the outside through this passage, and the lubrication and cooling of the gears of the synchronizing mechanism cannot be expected.

The present invention provides a piston pump or motor that solves the above problems.

[0008]

SUMMARY OF THE INVENTION A piston pump or motor provided by the present invention has spline teeth formed on the torque plate side and spline teeth formed on the center extending cylinder end of an annular cylinder block. The rotation synchronizing mechanism of the torque plate and the annular cylinder block is constituted by meshing the spline teeth of each other, and the spline meshing tooth portion is provided with a flow portion.
The fluid leaking inward of the annular cylinder block is sent out from the spline tooth meshing portion to the outside of the annular cylinder block.

[0009]

According to the piston pump or the motor provided by the present invention, the fluid (oil) leaking inward of the annular cylinder block cools the teeth of the spline tooth meshing portion when passing through the spline tooth meshing portion, and at the same time, Lubricate.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings. The structure of the piston pump or motor provided by the present invention is as shown in FIG. FIG. 1 is a cross-sectional view of the piston pump provided by the present invention, taken along the vertical axis including the center of the rotary shaft 3. The rotary shaft 3 is rotatable with respect to the casings 1 and 2 via bearings 4 and 5. Supported by. Reference numeral 1 is a casing main body portion, and 2 is a front cover portion, which are joined in a hermetically sealed state. The torque plate 6 is integrally fixed to the rotary shaft 3 near the front cover portion 2 via a screw coupling portion 2N, while the casing inner wall of the casing main body portion 1 has an inclined pressure receiving surface with respect to the rotary shaft 3. The annular cylinder block 10 is joined to this surface so as to come into sliding contact therewith. Reference numeral 9 is a piston fitted into each cylinder hole 10H formed in the annular cylinder block 10, and the outer end (spherical portion) of the piston is attached to the torque plate 6.
The side is pivotally supported. Although only one cylinder hole 10H and one piston 9 are shown in the annular cylinder block 10 in FIG.
The 0H and the piston 9 are arranged around the rotary shaft 3, and the other components are not shown. Further, in FIG. 1, an outlet and an inlet for oil communicating with the cylinder hole are formed on the inclined pressure receiving surface with which the annular cylinder block 10 is in sliding contact, but they are not shown in relation to the sectional position.
Reference numeral 1D is a discharge port that guides leaked oil in the casing to the drain.

The torque plate 6 has a piston retainer 7
Are fixed by bolts 8, and the outer ends (spherical portions) of the pistons are pivotally supported by the both 6 and 7. Further, a piston shoe 14 is embedded in the recess of the torque plate 6 via a backup nong 13, and the piston shoe 14 is
Is configured to be in sliding contact with the pressure receiving plate 15 embedded in the inner wall of the front cover portion 2.

The invention of the present application is characterized by the synchronizing mechanism of the annular cylinder block 10 side and the torque plate 6 side in the above-mentioned configuration. That is, as shown in FIG. 1, the annular cylinder block 10 has a tubular portion 10N extending in the piston outer end direction at its annular center portion, and outwardly extending spline teeth 10S at the extending tubular end portion. It is provided. On the other hand, the piston retainer 7 integrated with the torque plate 6 has an annular shape, and the inner peripheral surface of the central hole thereof has inwardly directed spline teeth 7S.
Are formed. The outward spline teeth 10S mesh with the inward spline teeth 7S. Outward spline teeth 10S on the side of the annular cylinder block 10
Is slightly projected to the feet of the torque plate 6, and thus the torque plate 6 is formed with an annular recess 6K so that the outward spline teeth 10S do not interfere with the torque plate 6. A compression spring 12 is press-fitted between the spring retainer 11 fixed to the annular cylinder block 10 and the torque plate 6.
Is urged to join the inclined pressure receiving surface of the casing inner wall of the casing body 1.

By the way, the meshing of the outward spline teeth 10S and the inward spline teeth 7S is as enlargedly shown in FIG. 2A, and the outward spline teeth 10S have different tooth shapes, that is, the gap A. Are provided and formed.
Each tooth 10S meshes with the spline tooth 7S on the piston retainer 7 side. The presence of this gap A facilitates the outflow of oil reaching this meshing portion. Immediately, as shown in FIG. 3, the oil leaking inward of the annular cylinder block 10 is extended as shown by the dotted line in the extending cylinder portion 1.
Although it flows out from 0N toward the outer end of the piston, the annular cylinder block 10 passes through the gap A at the meshing portion.
Spills outside. In FIG. 3 (A), the rotary shaft 3 and the like are omitted, and the flow of oil is illustrated for easy understanding.

As still another embodiment, as shown in an enlarged view in FIG. 2 (B), a through hole B may be formed in the meshing portion at the tip of the tubular portion 10N. This embodiment is shown in FIG.
It is as shown in FIG.

The piston pump or motor provided by the present invention is as described above, but is not limited to the above and illustrated examples and includes some modified examples. For example, in the above description, a hydraulic device is taken as an example of the fluid device, but a special water other than oil may be used as the fluid to be used, and the fluid is not limited to oil. Further, particularly regarding the formation of the spline tooth which is the main part of the invention, specifically, the inward spline tooth is formed on the torque plate side, and the outward spline tooth is formed at the center extending cylinder end of the annular cylinder block. It is also possible to reverse this. Further, the flow portion provided on the spline tooth may be provided on the inwardly facing spline tooth on the torque plate side. Further, the circulation portion does not have to be in the shape of a toothless tooth, and for example, an oil circulation hole may be formed in the tooth, and it is not limited to providing a gap. The shape of the gap is not limited to the illustrated example. Although the recess 6K is formed in the torque plate as shown in FIGS. 1 and 3, this is not always necessary. Further, the present invention provides a torque plate integrally provided at an inner end of a rotary shaft supported by a casing via a bearing, which has been used for a long time. The present invention can also be implemented in the case where the outer end of each piston is pivotally supported.
The present invention includes all these modifications.

The piston pump or the motor provided by the present invention is as described above, and the summary is as follows.

Appendix 1 Spline teeth are formed on the torque plate side, and
Spline teeth are formed on the central extension cylinder end of the annular cylinder block, and the rotation synchronizing mechanism of the torque plate and the annular cylinder block is configured by meshing both spline teeth with each other. A piston pump or a motor, wherein a circulation portion is provided, and fluid leaking inside the annular cylinder block is sent out from the spline tooth engagement portion to the outside of the annular cylinder block.

Appendix 2 Spline teeth are formed on the torque plate side, and
A spline tooth is formed at the center extension cylinder end of the annular cylinder block, and the rotation synchronizing mechanism of the torque plate and the annular cylinder block is configured by meshing both spline teeth with each other, and there is a gap between the spline engaging teeth. The piston pump or motor is characterized in that the fluid leaked inward of the annular cylinder block is sent out from the spline tooth meshing portion to the outside of the annular cylinder block.

Appendix 3 Inward spline teeth are formed on the torque plate side, and outward spline teeth are formed at the center extending cylinder end of the annular cylinder block. The inward spline teeth and the outward spline teeth are meshed with each other. By combining them, a rotation synchronizing mechanism of the torque plate and the annular cylinder block is configured, and a flow portion is provided in the spline meshing tooth portion, so that fluid leaking inward of the annular cylinder block is circulated from the spline tooth meshing portion to the annular cylinder block. A piston pump or motor characterized by being sent out to the outside.

Appendix 4 Inward spline teeth are formed on the torque plate side, and outward spline teeth are formed at the center extension cylinder end of the annular cylinder block. The inward spline teeth and the outward spline teeth are engaged with each other. By combining them, a torque plate and ring cylinder block rotation synchronization mechanism is configured.
A piston pump or a motor is characterized in that the spline meshing tooth portion is provided with a flow portion so that fluid leaking inward of the annular cylinder block is sent out of the spline tooth meshing portion to the outside of the annular cylinder block.

Appendix 5 The rotating shaft is supported by the casing via bearings, and a torque plate for pivotally supporting the outer end of each piston in the oblique axis direction is formed on the inner wall of the casing separately from the rotating shaft. A slant shaft type piston pump or motor having a rotary shaft penetrating the torque plate and a cylinder block having an annular rotation shaft, the inward spline teeth being arranged on the torque plate side. And the outwardly extending spline teeth are formed at the center extending cylinder end portion of the annular cylinder block, and the inwardly facing spline teeth and the outwardly facing spline teeth are meshed with each other to form a rotation synchronizing mechanism for the torque plate and the annular cylinder block. The spline meshing tooth part is provided with a flow part, and the fluid leaking inside the annular cylinder block The piston pump or motor is characterized in that the pump is sent out from the spline tooth meshing portion to the outside of the annular cylinder block.

Appendix 6 It is assumed that the rotating shaft is supported by the casing via bearings, and a torque plate that pivotally supports the outer end of each piston in the oblique axis direction is formed on the inner wall of the casing separately from the rotating shaft. A slant shaft type piston pump or motor having a rotary shaft penetrating the torque plate and a cylinder block having an annular rotation shaft, the inward spline teeth being arranged on the torque plate side. And the outwardly extending spline teeth are formed at the center extending cylinder end portion of the annular cylinder block, and the inwardly facing spline teeth and the outwardly facing spline teeth are meshed with each other to form a rotation synchronizing mechanism for the torque plate and the annular cylinder block. And the spline meshing teeth are provided with a gap so that fluid leaking inside the annular cylinder block can be retained. The piston pump or the motor is characterized in that the spline tooth meshing portion is used to send the spline tooth to the outside of the annular cylinder block.

Appendix 7 The rotating shaft is supported by the casing via bearings, and a torque plate pivotally supporting the outer ends of the pistons in the oblique axis direction is formed on the inner wall of the casing separately from the rotating shaft. A slant shaft type piston pump or motor having a rotary shaft penetrating the torque plate and a cylinder block having an annular rotation shaft, the inward spline teeth being arranged on the torque plate side. And the outwardly extending spline teeth are formed at the center extending cylinder end of the annular cylinder block, and the rotation synchronizing mechanism of the torque plate and the annular cylinder block is formed by meshing the inwardly facing spline teeth with the outwardly facing spline teeth. And the spline meshing teeth are provided with a gap so that fluid leaking inside the annular cylinder block is A piston pump or a motor, characterized in that it is sent out of the annular cylinder block from the plain tooth meshing portion.

[0024]

Since the piston pump or the motor provided by the present invention is as described above, the tooth gap in the spline mechanism (gear mechanism) as the synchronizing mechanism of the annular cylinder block and the torque plate can be reduced,
It is possible to provide a fluid device (oblique shaft type piston pump or motor) that generates less heat and generates less noise.

In particular, in the structure shown in the drawings of the embodiments, since the outward spline is formed on the annular cylinder block side, the inner surface shape of the centrally extending cylindrical portion of the annular cylinder block is simplified and the flow of leaked oil is improved. Further, since the outward spline is formed by providing a gap on the annular cylinder block side, there is an advantage that the flow of leaked oil is good and the tooth gap can be made small.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a piston pump or a motor according to the present invention.

FIG. 2 is a diagram showing a main part of the present invention.

FIG. 3 is a diagram showing an operation of a main part in the present invention.

[Explanation of symbols]

 1 ... Casing body part 2 ... Front cover part 3 ... Rotating shafts 4, 5 ... Bearings 6 ... Torque plate 7 ... Piston retainer 9 ... Piston 10 ... Annular cylinder block 10N ... Annular cylinder block center extension cylinder part 7S ... Torque plate side Inward spline teeth 10S ... Outward spline teeth on the annular cylinder block side A ... Gap B ... Through hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Omi 25, Saiin Oiwake-cho, Ukyo-ku, Kyoto Shimazu Corporation Gojo Plant

Claims (1)

[Claims] 1. An oblique shaft type piston pump or motor for pivotally supporting the outer end of each piston in the oblique axis direction, which is fitted into the annular cylinder block with respect to a torque plate which rotates integrally with a rotary shaft, wherein: A spline tooth is formed on the torque plate side, a spline tooth is formed on the central extension cylinder end of the annular cylinder block, and both of these spline teeth engage with each other to create a rotation synchronization mechanism for the torque plate and the annular cylinder block. A piston pump characterized in that a fluid flow portion is provided in the spline meshing tooth portion, and fluid leaking inside the annular cylinder block is sent out from the spline tooth meshing portion to the outside of the annular cylinder block. Or motor.