阅读说明：本技术 一种回程盘与斜盘一体化设计的柱塞泵 (Plunger pump with integrated return disc and swash plate ) 是由 张新华 黄建 周围 肖中卓 霍希建 鄢梦 刘海 李晓斌 赵帆 于 2020-12-02 设计创作，主要内容包括：本发明公开了一种回程盘与斜盘一体化设计柱塞泵,包括斜盘(2)、回程盘(8)、旋转支撑(10)、回程盘支撑(11),所述回程盘支撑(11)穿过所述斜盘(2)的内孔,与所述斜盘(2)之间通过所述旋转支撑(10)连接,两者可相对转动,所述回程盘支撑(11)与所述回程盘(8)连接。本发明降低了柱塞泵产品开发成本,提高了柱塞泵的动态性能和容积效率。(The invention discloses a plunger pump with a return disc and a swash plate in an integrated design, which comprises a swash plate (2), a return disc (8), a rotary support (10) and a return disc support (11), wherein the return disc support (11) penetrates through an inner hole of the swash plate (2) and is connected with the swash plate (2) through the rotary support (10) and can rotate relatively, and the return disc support (11) is connected with the return disc (8). The invention reduces the development cost of plunger pump products and improves the dynamic performance and volumetric efficiency of the plunger pump.)

1. A plunger pump with a return disc and a swash plate in an integrated design comprises a main shell (1), a swash plate (2), a cylinder body supporting frame (3), a cylinder body (4), a rear cover (5), a central spring (6), a plunger (7), a return disc (8), a sliding shoe (9), a rotary support (10), a return disc support (11) and a main shaft (13), wherein the swash plate (2) is fixedly connected inside the main shell (1); the return disc (8) presses the slipper (9) on the swash plate (2); the plunger (7) is connected with the sliding shoe (9), inserted into the inner hole of the cylinder body (4) and pressed on the swash plate (2) by the return plate (8); the main shaft (13) is fixed on the main shell (1) through a bearing, penetrates through an inner hole of the return disc support (11) and is propped against a central spring (6) embedded in an inner hole of the cylinder body, meanwhile, the main shaft (13) and the cylinder body (4) transmit rotation through a spline, the central spring (6) presses the cylinder body (4) to the rear cover (5), the hydraulic cylinder is characterized in that,

the return disc support (11) penetrates through an inner hole of the swash plate (2) and is connected with the swash plate (2) through the rotary support (10), the swash plate support and the rotary support can rotate relatively, and the return disc support (11) is connected with the return disc (8).

2. A plunger pump with integrated return disc and swash plate design as claimed in claim 1, characterized in that the rotating support (10) is a bearing roller, the inner hole of the swash plate (2) is used as the outer ring of the bearing stator, and the outer wall of the return disc support (11) is used as the inner ring of the bearing rotor of the rotating support (10).

3. The plunger pump of claim 2, characterized in that the inner hole surface of the swash plate (2) is coated with tetrafluoroethylene wear-resistant coating, the outer wall surface of the return disc support (11) is coated with tetrafluoroethylene wear-resistant coating, and the surface is carburized and nitrided to enhance the hardness of the material.

4. The plunger pump of claim 2, wherein the inner hole side wall is provided with an oil passing hole having a diameter of less than 1mm, the oil passing hole communicating the swash plate bearing side with the shoe sliding side.

5. A return disc and swash plate integrated plunger pump according to claim 2, characterized in that the return disc support (11) passes through the inner bore of the swash plate (2) and is connected to the return disc (8) by a screw thread.

6. The plunger pump of claim 5, wherein the rollers of the rotary support (10) and the inner and outer rings have a certain clearance, the axial clearance is less than 15um, and the radial clearance is kept between 0.15 mm and 0.3 mm.

7. A plunger pump with integrated return disc and swash plate design according to claim 6 characterized in that the rollers of the rotary support (10) are balls or rollers, single row or double row, the roughness of the roller surface reaches Ra0.4, and the material is wear resistant material.

8. The plunger pump of claim 7, wherein GCr15 is selected as roller material, and the surface hardness is HRC58-62 by solution aging treatment.

9. The plunger pump with the integrated design of the return disc and the swash plate as in claim 5, wherein a torque measurement tool interface is reserved on the return disc support (11).

Technical Field

The invention belongs to the technical field of hydraulic element plunger pumps, and particularly relates to a plunger pump with a return disc and a swash plate in integrated design.

Background

The hydraulic element plunger pump is an important energy conversion element in a high-pressure hydraulic system, changes the volume of hydraulic oil in a closed cavity by means of the reciprocating motion of a plunger in a cylinder body, realizes the suction/extrusion of the hydraulic oil in a hydraulic loop, and converts mechanical energy provided by a motor into hydraulic energy. The plunger pump has the advantages of high rated pressure, compact structure, high efficiency, convenient flow regulation and the like, and is widely applied to the industries of aerospace, engineering machinery and the like. The plunger pump industry in China is developed and started late, has a large difference with foreign technical levels, mainly depends on import in high-end markets, has 3 thousands of product gaps every year, and is a key neck clamping technology for restricting the development of industrial hydraulic technology in China.

The plunger pump mainly comprises key components such as a valve plate, a swash plate, a cylinder body, a plunger, a sliding shoe, a ball head, a return plate, a main shaft and the like, the plunger reciprocates in the cylinder body through the swash plate, the components move relatively to each other during working, and if design parameters are improper, faults are easily caused, wherein the structural design at the swash plate-return plate position is a main contradiction point. The parts at the swash plate-return plate part have complex structures: the swash plate passes through the flange or the pinhole is fixed on the pump casing, and the return stroke dish is connected with the pump rotor to press 7 ~ 9 piston shoes on the swash plate, make the piston shoe laminating motion on the swash plate. There are generally two methods of connecting the swash plate to the pump rotor, the first being: the design method can realize zero clearance between the return disc, the slipper and the swash plate, reduce the leakage of the pump and improve the volumetric efficiency of the pump, but the design method is complex and has more structural components, because the spring participates in transmission, the size chain is difficult to control, the return disc can not be radially positioned by using a bearing, the spring modulus, the ball head precision and the surface roughness, the tolerance design of the slipper and the return disc and the like all need a large amount of theoretical calculation, the fluid-solid coupling problem caused by the complex structure increases the calculation difficulty, usually, a plurality of product prototypes are needed for iterative tests, and great difficulty is caused to the development of new products. In practical use, the return disc is not radially fixed, and the rotation of the return disc is driven by the sliding shoes, so that the problems of eccentric wear of the sliding shoes, loosening of the return disc and the like are easily caused, and the plunger pump is easily broken down particularly at high speed. The second structural form is as follows: the axial movement of the return disc is limited by the clamping groove, and the sliding shoe is pressed on the swash plate. The design method is simple, but the gap amount is difficult to control, the piston shoe internal leakage is easy to occur, the volume efficiency of the plunger pump is reduced, the radial size of a rotor part is large, the rotational inertia is large, and the dynamic performance of the pump is influenced. In addition, the reversing performance of the pump can be influenced by the gap of the clamping groove during reversing, high noise is generated, the return disc is damaged even if the pump works under high pressure for a long time, metal fragments are generated, and serious problems such as dead failure of a plunger, breakage of the return disc and the like are caused immediately.

Disclosure of Invention

The invention aims to provide a plunger pump with simple design method and reliable performance.

In order to solve the technical problem, the invention provides a plunger pump with an integrated return disc and a swash plate, which adopts the following technical scheme:

the hydraulic cylinder comprises a main shell, a swash plate, a cylinder body supporting frame, a cylinder body, a rear cover, a central spring, a plunger, a return disc, a sliding shoe, a rotary support, a return disc support and a main shaft. The swash plate is fixedly connected inside the main shell; the return disc presses the slipper on the swash plate; the plunger is connected with the sliding shoe, inserted into the inner hole of the cylinder body and pressed on the swash plate by the return plate; the main shaft is fixed on the main shell through a bearing, penetrates through an inner hole supported by the return disc and abuts against a central spring embedded in an inner hole of the cylinder body, and meanwhile, the main shaft and the cylinder body rotate through spline transmission, and the central spring presses the cylinder body to the rear cover. The return disc support penetrates through the inner hole of the swash plate and is connected with the swash plate through the rotary support, the return disc support and the return disc can rotate relatively.

Furthermore, the rotary support is a bearing roller, the inner hole of the swash plate is used as the outer ring of a bearing stator, and the outer wall of the return plate support is used as the inner ring of a bearing rotor of the rotary support.

Further, the return disc supports an inner hole penetrating through the swash plate and is connected with the return disc through threads.

According to the invention, through the integrated design of the return disc and the swash plate, the structure of the return disc and the swash plate of the plunger pump is simplified, the design method of the return disc and the swash plate is simplified, and the product development cost of the plunger pump is reduced; the return disc is used for supporting the inner ring of the rotor as a rotary support, and the swash plate is used as the outer ring of the stator, so that the radial size of the rotor is greatly reduced, and the dynamic performance of the plunger pump is improved; under the condition of not using a spring, the axial clearance is eliminated through the integrated design of the return disc and the swash plate, the volume efficiency is improved, and the stable performance can be ensured under different working pressures and rotating speeds.

Drawings

FIG. 1 is a schematic view of the integrated design structure of a return disc and a swash plate according to the present invention;

the hydraulic cylinder comprises a main shell 1, a main shell 2, a swash plate 3, a cylinder body supporting frame 4, a cylinder body 5, a rear cover 6, a center spring 7, a plunger 8, a return disc 9, a sliding shoe 10, a rotary support 11, a return disc support 12, a rotary seal 13, a main shaft 14 and a front cover.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

In one embodiment of the present invention, the plunger pump with the integrated design of the return disc and the swash plate comprises a main housing 1, a swash plate 2, a cylinder support frame 3, a cylinder 4, a rear cover 5, a center spring 6, a plunger 7, a return disc 8, a slipper 9, a rotary support 10, a return disc support 11, a rotary seal 12, a main shaft 13 and a front cover 14, wherein the swash plate 2 is fixedly connected inside the main housing 1, and the return disc support 11 penetrates through an inner hole of the swash plate 2 and is connected with the swash plate 2 through the rotary support 10, and the two can rotate relatively.

The cylinder block 4 is connected with the cylinder block supporting frame 3 and then connected with the main shell through a bearing, and the plunger 7 is connected with the sliding shoe 9 and inserted into the inner hole of the cylinder block 4 to be pressed on the swash plate 2 by the return plate 8. The main shaft 13 is fixed on the main shell 1 through a bearing, penetrates through an inner hole of the return disc support 11 and abuts against the central spring 6 embedded in the inner hole of the cylinder body, meanwhile, the main shaft 13 and the cylinder body 4 rotate through spline transmission, the cylinder body 4 is pressed towards the rear cover 5 through the central spring 6, the sealing performance between the cylinder body 4 and the rear cover 5 is guaranteed, and the pressing force between the cylinder body 4 and the rear cover 5 is adjusted through the pretightening force of the spring.

The main shaft 13 is connected with an external input rotating part through a spline, when the main shaft 13 rotates, the cylinder body 4 is driven to rotate, the plunger 7 in the cylinder body 4 also rotates along with the cylinder body, and as the plunger 7 is pressed on the swash plate 2 by the return plate 8, the plunger 7 axially reciprocates while rotating, so that the volume change of a plunger cavity formed by the plunger 7 and the cylinder body 4 is realized, and oil pumping and oil pressing are realized.

The main shaft 13 is radially supported by the rotary seal 12 and the deep groove ball bearing, and is axially positioned by a positioning straight opening of the front end cover 14, the rotary seal 12 can be selected from rotary seals of mature manufacturers at home and abroad, and the minimum sealing pressure is more than 0.5 MPa. The surface roughness of the spindle 13 should be machined according to the requirements in the product manual for the rotary seal 12.

In one embodiment of the invention, the rotary supports 10 are bearing rollers, using the swash plate 2 as the outer ring stator and the return plate support 11 as the inner ring rotor. The return disc support 11 is a conical structure, the outer wall of the cone of the return disc support is used as the inner ring of the rotary support 10, and the cone part of the return disc support passes through the inner hole of the swash plate 2 and is connected with the return disc 8 through threads. The technological slotted holes are machined in the swash plate 2 and the return plate support 11 to ensure that the threads are screwed tightly.

The return disc 8 presses the sliding shoes 9 on the swash plate 2, pressing force and clearance between the sliding shoes 9 and the swash plate 2 are adjusted through threads between the rotary return disc 8 and the return disc support 11, the pressing force and the clearance are determined according to actual working conditions, if external loads are strict for dynamic performance examination, the positive and negative reversing of the plunger pump is required to be rapid, and the pressing force is required to be improved. If the requirement of the external load on the static load is high, the pressing force should be reduced, so that a certain gap is still kept between the rotary support 11 and the swash plate 2 under the heavy load.

And a torque measurement tool interface is reserved on the return disc support 11 so as to measure the rotation torque of the rotary support 11.

In one embodiment of the present invention, the rollers of the rotary support 10 may be balls or rollers, and may be single-row or double-row rollers, the surface roughness of the rollers should reach ra0.4, and the materials should be wear-resistant materials.

Preferably, GCr15 is selected as a roller material, and the surface hardness is enhanced through solution aging treatment so as to reach HRC 58-62.

In one embodiment of the invention, a certain gap is reserved between the roller of the rotating support 10 and the inner and outer rings, the axial gap is less than 15um, the radial gap is kept between 0.15 mm and 0.3mm, and the oil film supporting force and the rotating lateral force can be kept balanced under the gap, so that the bearing wear is reduced.

In one embodiment of the invention, the inner hole of the swash plate 2 is used as a bearing outer ring and the surface of the bearing outer ring is coated with a tetrafluoroethylene anti-abrasion coating, the outer wall of the return plate support is used as a bearing inner ring and is coated with the tetrafluoroethylene anti-abrasion coating, and the surface is carburized and nitrided to enhance the hardness of the material.

In one embodiment of the invention, the side wall of the inner hole of the swash plate 2 is provided with an oil through hole with the diameter smaller than 1mm, the oil through hole communicates the bearing side of the swash plate with the sliding side of the slipper, and when the pressure of the plunger pump shell is higher, oil can lubricate the bearing through the oil through hole.