CN114718831B

CN114718831B - High-pressure manual pump for closed hydraulic system

Info

Publication number: CN114718831B
Application number: CN202210329712.2A
Authority: CN
Inventors: 苏琦; 晁念普; 唐玲; 徐兵; 黄伟迪; 纵怀志; 关铁汉; 刘清
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2023-05-02
Anticipated expiration: 2042-03-30
Also published as: CN114718831A

Abstract

The invention discloses a high-pressure manual pump capable of being used for a closed hydraulic system, which aims to ensure that the manual pump is reliably driven under the condition of high pressure load, adopts a novel swash plate structural design, adopts involute spline transmission, processes a rolling steel ball track on the working surface of a swash plate, performs power output transmission through a steel column and a plunger, ensures the reliable force transmission state of the plunger and the swash plate when the load pressure is high, improves the stress state of the plunger, reduces the lateral overturning force of the plunger, avoids the lateral overturning of the plunger and reduces abrasion. By the special design of the runner block, the recycling of leaked oil in the closed hydraulic system and the non-stop oil supplementing and filling function of the closed system in any working process of forward and reverse rotation can be realized. The manual pump can be applied to a higher closed working pressure environment, and has great application value in the aspects of vehicles, agriculture and forestry, military industry and the like.

Description

High-pressure manual pump for closed hydraulic system

Technical Field

The invention relates to the field of manual hydraulic pump design, in particular to a high-pressure manual pump which can be used for a closed hydraulic system.

Background

The hydraulic pump is used as an important power element in the current industrial industry, is widely applied and comprises aerospace, traveling vehicles, mine equipment and the like, and is mainly driven by a motor or an engine to output high-pressure oil power to a hydraulic cylinder or a hydraulic motor, but in some important fields, a set of reliable manual standby system is often required to be arranged for guaranteeing the reliability of the system, and the flow, the pressure and the volume of the current manual pump are also required to be higher and higher for covering various working conditions.

Disclosure of Invention

Aiming at a closed hydraulic system, the novel manual hydraulic pump design is provided, the harsh requirements on flow and pressure can be met under various complex application environments, meanwhile, the forward and reverse working can be rapidly switched, the compensation effect on lateral force of a plunger can be realized through a swash plate structure, faults such as overturning and wearing of the plunger under a heavy load condition are avoided, the recycling of leaked oil in the closed hydraulic system and the non-stop oil supplementing and filling functions of the closed system in any working process of forward and reverse rotation can be realized, and the hydraulic pump can be used as a reliable main system oil supply pump or a standby system power source and is applied to the extension and retraction of a hydraulic cylinder or the forward and reverse rotation of a hydraulic motor.

In order to realize the functions and the performance requirements, the invention adopts the following technical scheme: a high-pressure manual pump for a closed hydraulic system comprises a rocking handle, a front end cover, an angular contact ball bearing, a sloping cam plate, rolling steel balls, a plunger, a spline shaft, a deep groove ball bearing, a cylinder body, a shell and a runner block;

the manual pump is driven by a rocking handle, the rocking handle is connected with a spline shaft through a bolt and used for power input, the sloping cam plate is connected with the spline shaft through an involute spline to realize power transmission, and a rolling steel ball movement track is designed on the working surface of the sloping cam plate; the circle center distribution of the radius of the track coincides with the surface of the sloping cam plate; one end of the spline shaft is connected with the cylinder body through a deep groove ball bearing, and the other end of the spline shaft is connected with the front end cover through an angular contact ball bearing; the front end cover is fixed on the shell; plunger holes are uniformly distributed in the cylinder body, the plungers are arranged in the plunger holes of the cylinder body, the axis of each plunger is parallel to the axis of the cylinder body, and a spherical groove is formed in the top of each plunger and is used for installing rolling steel balls; when the device works, one half of the rolling steel balls are positioned in the spherical groove at the top of the plunger, the other half of the rolling steel balls are positioned in the rolling steel ball track of the sloping cam plate, are in a line contact state with the working surface of the sloping cam plate, are in a surface contact state with the spherical groove of the plunger, and are always restrained to move in the track in the working process;

the flow passage block is connected with the shell, a first hydraulic control two-position three-way valve and a second hydraulic control two-position three-way valve are integrated in the flow passage block, wherein an oil inlet of the second hydraulic control two-position three-way valve is connected with a leakage oil outlet of the high-pressure manual pump, an oil inlet of the first hydraulic control two-position three-way valve is connected with an oil supplementing port of the high-pressure manual pump through a one-way valve, and two oil outlets of the first hydraulic control two-position three-way valve and the second hydraulic control two-position three-way valve are respectively connected with a high-pressure oil path and a low-pressure oil path of the closed hydraulic system.

Further, the bottom surface of the swash plate is perpendicular to the axis of the swash plate, the working surface and the bottom surface of the swash plate form a certain included angle, the included angle is determined according to the displacement of the manual pump, and in the working process, the swash plate and the rolling steel balls are in a line contact state, so that the radial force in the movement of the plunger can be overcome, and the reliable power transmission is ensured.

Further, two hydraulically-controlled two-position three-way valves are installed in parallel in the runner block and used for recycling leaked oil in the closed hydraulic system by the manual pump and supplementing oil and filling oil to the closed system without stopping in any working process of positive and negative rotation.

Further, the plunger is of a cylindrical revolving body structure, a cavity is formed in the plunger, the plunger is used for installing a compression spring, the other end of the compression spring is installed on a spring base, and the spring base is used for sealing the bottom of a plunger hole; a waist-shaped groove is designed on the outer side of the plunger and used for distributing oil in the high-pressure cavity and the low-pressure cavity.

Further, the cylinder body is installed inside the shell, is pressed in the inner cavity of the shell through the rear end cover, and 8 plunger holes uniformly distributed along the circumference are formed in the cylinder body, and the axes of the plunger holes are parallel to the axis of the cylinder body. An upper runner and a lower runner are arranged in each plunger hole and matched with the waist-shaped grooves to realize flow distribution, and the upper runner of each plunger hole is communicated with the lower runner of the other plunger hole with the interval of 1 according to the clockwise or anticlockwise sequence. The side of the cylinder body is provided with a runner groove for oil to enter and exit, the runner groove is communicated with the side walls of the 8 plunger holes, and the side of the cylinder body is also provided with 3 grooves for installing sealing rings.

Further, the spline shaft is provided with a stepped retainer ring for axially limiting the swash plate, and the axis of the spline shaft coincides with the axis of the cylinder body.

Further, the high-pressure manual pump also comprises a large bearing seat and a small bearing seat; the large bearing seat and the small bearing seat are respectively arranged at the bottoms of the angular contact ball bearing and the deep groove ball bearing, and grooves for installing sealing rings are formed in the inner ring and the outer ring of the large bearing seat and the small bearing seat and are used for sealing oil.

Structural principle: through rocking the rocking handle for manual pump integral key shaft is rotatory, and the integral key shaft then drives the sloping cam plate and rotates, the plunger is owing to the compression spring force of plunger bottom, firmly compress tightly at sloping cam plate working surface through the rolling steel ball, because the sloping cam plate has certain inclination, along with the rotation of sloping cam plate, the plunger reciprocates rectilinear motion in the inside plunger cavity of cylinder body, combine the design of joining in marriage of plunger and cylinder body, every plunger is accomplished once and is inhaled, the oil extraction process, along with the pressure in the plunger cavity increases, hydraulic pressure is through the plunger, the rolling steel ball, sloping cam plate and ladder retaining ring effect on angular contact ball bearing, the steel ball is the sphere contact with the plunger, be the line contact with the track on the sloping cam plate, for the point contact, the track face can offset a part plunger lateral force, can satisfy still can keep good lubrication under great hydraulic pressure effect, and stress state, reduce the friction degree of plunger, improve plunger, the sloping cam plate life-span.

The high-pressure manual pump for the closed hydraulic system has the advantages that: the structure is compact, the outlet flow pulsation is small, the special swash plate structure and the rolling steel ball design are adopted, the linear-surface power transmission is realized, the plunger anti-overturning capacity is high, the axial bearing capacity is high, the friction loss is small, the structure is simple, and the service life of core parts is prolonged. And the two hydraulic control two-position three-way valves are connected in parallel through the runner block, so that the manual pump has the functions of recycling leaked oil and supplementing oil of an external system under forward and reverse working conditions, and has great use value in the important fields of aerospace, mining machinery and the like.

Drawings

The manual pump is further described below with reference to the drawings and detailed description.

FIG. 1 is a schematic overall appearance of a high pressure manual pump that may be used in a closed hydraulic system.

Fig. 2 is a schematic diagram of an assembled construction of a high pressure manual pump that may be used in a closed hydraulic system.

Fig. 3 is a view of a swash plate forward part.

Fig. 4 is a cross-sectional view of the swash plate a.

Fig. 5 is a side view of the plunger and a cross-sectional view of the plunger a.

Fig. 6 is a flow block hydraulic flow schematic.

Fig. 7 is a top view of the cylinder and a named drawing of the plunger hole number.

Fig. 8 is a sectional view of the cylinder a.

Fig. 9 is a simplified diagram of a swash plate steel ball.

Reference numerals: 1. the hydraulic control system comprises a rocking handle, a front end cover, a large bearing seat 3, an angular contact ball bearing 4, a stepped retainer ring 5, a swash plate 6, a rolling steel ball 7, a plunger 8, a compression spring 9, a spline shaft 10, a deep groove ball bearing 11, a small bearing seat 12, a cylinder body 13, a shell 14, a spring base 15, a rear end cover 16, a flow channel block 17, a connecting block 18, a first hydraulic control two-position three-way valve 17.1, a second hydraulic control two-position three-way valve 17.3 and a one-way valve.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

Referring to fig. 1 to 9, the invention provides a high-pressure manual pump for a closed hydraulic system, which comprises a rocking handle 1, a front end cover 2, a large bearing seat 3, an angular contact ball bearing 4, a stepped retainer 5, a swash plate 6, a rolling steel ball 7, a plunger 8, a compression spring 9, a spline shaft 10, a deep groove ball bearing 11, a small bearing seat 12, a cylinder 13, a shell 14, a spring base 15, a rear end cover 16, a runner block 17 and a connecting block 18, wherein two hydraulic control two-position three-way valves are arranged in the runner block 17, an inlet of a first hydraulic control two-position three-way valve 17.1 is used for connecting an oil supplementing oil way through a one-way valve 17.3, an inlet of a second hydraulic control two-position three-way valve 17.2 is communicated with a leakage oil port on a manual pump housing 14, and two outlets of the two hydraulic control two-position three-way valves are respectively communicated with an oil inlet and an oil outlet of the manual pump. The cylinder body 13 of the manual pump is tightly pressed in the inner cavity of the shell 14 through the rear end cover 16 by adopting bolts, A, B oil grooves on the cylinder body 13 are respectively connected with the runner block 17 through oil inlet and outlet ports on the

shell

14, 8 plungers 8 are correspondingly arranged in 8 plunger holes of the cylinder body respectively, the bottom of each plunger 8 is provided with a compression spring 9, each compression spring 9 is divided into an upper spring part and a lower spring part, the middle parts of the compression springs are connected together through the connecting blocks 18, and the spring base 15 is used for sealing the bottoms of the plunger holes; the outside of the plunger is provided with a waist-shaped groove for distributing oil in a high-pressure cavity and a low-pressure cavity, the top of the plunger 8 is used for installing rolling steel balls 7, under the action of a compression spring 9, the rolling steel balls 7 are compressed in steel ball tracks on the surface of the swash plate 6 through the plunger 8, and the steel balls are in surface contact with the plunger ball-shaped groove and in line contact with the steel ball tracks of the swash plate 6; the swash plate 6 is arranged on a spline shaft 10 through a spline, the back side is axially limited through a stepped retainer ring 5, the front side is in contact with a rolling steel ball 7, one end of the spline shaft 10 is connected with a cylinder body 13 through a deep groove ball bearing 11, the other end of the spline shaft is connected with a front end cover 2 through an angular contact ball bearing 4, a large bearing seat 3 and a small bearing seat 12 are respectively arranged at the bottom of the bearing and used for axial sealing, the front end cover 2 is arranged on a shell 14 through bolts, a rocking handle 1 is arranged at the extending end of the spline shaft 10 through bolts, the manual pump is usually used for a closed hydraulic system but is not limited to the closed hydraulic system, and the conventional driving mode is manual rotation of the rocking handle 1 but not limited to manual driving.

Working principle: the hand pump is configured by the special structural design of a cylinder body and a plunger, as shown in fig. 7, 8 plunger holes (a first plunger hole 13.1, a second plunger hole 13.2, a third plunger hole 13.3, a fourth plunger hole 13.4, a fifth plunger hole 13.5, a sixth plunger hole 13.6, a seventh plunger hole 13.7 and an eighth plunger hole 13.8) on the cylinder body 13 are parallel to the axis of the cylinder body 13, the plungers are uniformly distributed in the plunger holes, the swash plate 6 has a certain inclination angle beta, when the crank 1 drives the spline shaft 10 to rotate, the plunger can do reciprocating linear motion in a plunger cavity of the cylinder body 13 due to the pressing force of the swash plate 6 on the rolling steel balls 7, and at any moment, 1 plunger is always located at an upper limit point, 1 plunger is located at a lower limit point, 3 plungers are in a downward oil-sucking motion state, 3 plungers are in an upward oil-sucking motion state, and each plunger 8 realizes one oil sucking and discharging process every time when the crank 1 rotates for one circle.

When high-pressure oil is generated at the bottom of the plunger 8, the bottom of the plunger 8 is subjected to certain hydraulic pressure, the hydraulic pressure acts on the swash plate 6 through the rolling steel balls 7, the steel balls are in spherical contact with the plunger 8 and are in linear contact with the swash plate 6, the acting force of the swash plate 6 on the steel balls can be decomposed into axial and radial directions, the radial acting force is born through steel ball tracks on the swash plate 6, the plunger is prevented from being subjected to overturning moment, the stress condition of the plunger is improved, the lubrication characteristic and the bearing capacity are improved, and finally the hydraulic pressure in the axial direction is transmitted to the angular contact ball bearing 4 through the stepped retainer ring 5.

When the rocking handle 1 rotates, oil is discharged from the A-port runner, under the action of high-pressure cavity pressure, a valve core of the hydraulic control two-position three-way valve in the runner block 17 is pushed, the leaked oil in the inner cavity of the shell 14 and the oil supplementing loop are communicated with the B-port low-pressure runner through the hydraulic control two-position three-way valve, when the rotation direction of the rocking handle 1 is changed, the oil inlet and outlet ports are switched, the oil is discharged from the B-port runner, at the moment, the position of the valve core of the hydraulic control two-position three-way valve is also changed under the action of pressure oil, and the leaked oil in the inner cavity of the shell 14 and the oil supplementing loop are communicated with the A-port runner through the hydraulic control two-position three-way valve. Because the oil supplementing port is always communicated with the low-pressure port in the pump system, the system is allowed to be supplemented under the conditions of forward and reverse rotation of the manual pump and any load pressure.

The specific preparation process of the cylinder body and the plunger is as follows:

the communicating mode of the flow passages in each plunger hole on the cylinder body 13 is that a first plunger hole upper flow passage 13.1-1 is communicated with a third plunger hole lower flow passage 13.3-2, a second plunger hole upper flow passage 13.2-1 is communicated with a fourth plunger hole lower flow passage 13.4-2, a third plunger hole upper flow passage 13.3-1 is communicated with a fifth plunger hole lower flow passage 13.5-2, a fourth plunger hole upper flow passage 13.4-1 is communicated with a sixth plunger hole lower flow passage 13.6-2, a fifth plunger hole upper flow passage 13.5-1 is communicated with a seventh plunger hole lower flow passage 13.7-2, a sixth plunger hole upper flow passage 13.6-1 is communicated with an eighth plunger hole lower flow passage 13.8-2, a seventh plunger hole upper flow passage 13.7-1 is communicated with the first plunger hole lower flow passage 13.1-2, and an eighth plunger hole upper flow passage 13.8-1 is communicated with the second plunger hole lower flow passage 13.2-2. Because of the matching relation between the A, B port on the cylinder 13 and the waist-shaped groove of the plunger, when the plunger is positioned between the upper limit position and the midpoint of the full stroke, the upper runner port in the plunger cavity is communicated with the A port on the cylinder 13 through the waist-shaped groove, and the B port in the plunger cavity is closed by the plunger; when the plunger is positioned between the full stroke midpoint and the lower limit position, the port A in the plunger cavity is closed by the plunger, and the upper runner port is communicated with the port B on the cylinder body 13 through the waist-shaped groove.

When the plunger in the first plunger hole 13.1 moves downwards from the upper limit position, the first plunger hole lower runner 13.1-2 at the bottom of the plunger is communicated with the seventh plunger hole upper runner 13.7-1, and as the plunger in the first plunger hole 13.1 is 90 degrees different from the plunger in the seventh plunger hole 13.7, the plunger position in the seventh plunger hole 13.7 is always between the upper limit position and the full stroke midpoint in the process of pressing downwards the plunger in the first plunger hole 13.1, at the moment, the upper runner in the plunger cavity in the seventh plunger hole 13.7 is communicated with the upper port A of the cylinder body 13, and the pressure oil generated at the bottom of the plunger in the first plunger hole 13.1 flows out from the port A in the plunger cavity in the seventh plunger hole 13.7 through the first plunger hole lower runner 13.1-2-seventh plunger hole upper runner 13.7-1; when the plunger in the first plunger hole 13.1 absorbs oil upwards from the lower limit position, the plunger position in the seventh plunger hole 13.7 is always between the full stroke midpoint and the lower limit position, at the moment, an upper runner in a plunger cavity in the seventh plunger hole 13.7 is communicated with a port B on the cylinder body 13, low-pressure oil enters the bottom of the plunger in the first plunger hole 13.1 from the port B through the first plunger hole lower runner 13.1-2 and the seventh plunger hole upper runner 13.7-1, the oil filling process is completed, and the analysis principle of other plunger working processes is the same. At this time, the port A of the pump is a high-pressure oil outlet, the port B is a low-pressure oil inlet, and the valve core of the hydraulic control two-position three-way valve in the flow channel block 17 is pushed under the action of the high-pressure oil of the port A, so that the leakage oil inside the shell 14 and the external oil supplementing flow channel are communicated with the low-pressure oil suction port B.

When the rocking handle 1 is reversely rotated, in the process that the plunger in the first plunger hole 13.1 moves downwards from the upper limit position, the plunger position in the seventh plunger hole 13.7 is always positioned between the full stroke midpoint and the lower limit position, at the moment, an upper runner in a plunger cavity in the seventh plunger hole 13.7 is communicated with a port B on the cylinder body 13, and pressurized oil generated at the bottom of the plunger in the first plunger hole 13.1 flows out from the port B in the plunger cavity in the seventh plunger hole 13.7 through a lower runner 13.1-2 of the first plunger hole and an upper runner 13.7-1 of the seventh plunger hole; when the plunger in the first plunger hole 13.1 absorbs oil upwards from the lower limit position, the plunger position in the seventh plunger hole 13.7 is always between the upper limit position and the midpoint of the full stroke, at this time, the upper runner in the plunger cavity in the seventh plunger hole 13.7 is communicated with the upper port A of the cylinder body 13, low-pressure oil enters the bottom of the plunger in the first plunger hole 13.1 from the port A through the lower runner 13.1-2 of the first plunger hole and the upper runner 13.7-1 of the seventh plunger hole, the oil filling process is completed, and the analysis principle of other plunger working processes is the same. At this time, the port B of the pump is a high-pressure oil outlet, the port A is a low-pressure oil inlet, and the position of the valve core of the hydraulic control two-position three-way valve in the flow passage block 17 is changed under the action of the high-pressure oil of the port B, so that the leakage oil in the shell 14 and the external oil supplementing flow passage are communicated with the low-pressure oil suction port A.

Finally, it should be noted that the above description is only a specific application example of the present invention, and is not intended to limit the present invention, and other application examples that are the same as the basic principles of the present invention should also fall within the protection scope of the present invention.

Claims

1. A high pressure manual pump for a closed hydraulic system, characterized by: the device comprises a rocking handle, a front end cover, an angular contact ball bearing, a sloping cam plate, rolling steel balls, a plunger, a spline shaft, a deep groove ball bearing, a cylinder body, a shell and a runner block;

2. A high pressure manual pump for a closed hydraulic system according to claim 1, wherein the swashplate bottom surface is perpendicular to the swashplate axis, and the working surface is at an angle to the swashplate bottom surface, said angle being determined based on the displacement of the manual pump.

3. The high-pressure manual pump for the closed hydraulic system according to claim 1, wherein two hydraulic control two-position three-way valves are arranged in parallel in the flow passage block and are used for recycling leaked oil in the closed hydraulic system and supplementing oil to the closed system without stopping in any working process of positive and negative rotation.

4. The high-pressure manual pump applicable to a closed hydraulic system according to claim 1, wherein the plunger is of a cylindrical revolving body structure, a cavity is formed in the plunger, the plunger is used for installing a compression spring, the other end of the compression spring is installed on a spring base, and the spring base is used for sealing the bottom of a plunger hole; a waist-shaped groove is designed on the outer side of the plunger and used for distributing oil in the high-pressure cavity and the low-pressure cavity.

5. The high-pressure manual pump applicable to the closed hydraulic system according to claim 1, wherein the cylinder body is arranged in the shell, the cylinder body is pressed in the inner cavity of the shell through the rear end cover, 8 plunger holes uniformly distributed along the circumference are arranged in the cylinder body, and the axis of the plunger holes is parallel to the axis of the cylinder body.

6. The high-pressure manual pump for a closed hydraulic system according to claim 5, wherein an upper runner and a lower runner are arranged in each plunger hole, the upper runner of each plunger hole is communicated with the lower runner of the other plunger hole with a gap of 1 in a clockwise or anticlockwise order in cooperation with the waist-shaped groove to realize flow distribution.

7. The high-pressure manual pump for a closed hydraulic system according to claim 5, wherein the side surface of the cylinder body is provided with a runner groove for oil to enter and exit, the runner groove is communicated with the side walls of the 8 plunger holes, and the side surface of the cylinder body is further provided with 3 grooves for installing sealing rings.

8. The high-pressure manual pump for a closed hydraulic system according to claim 1, wherein the spline shaft is provided with a stepped retainer ring for axially limiting a swash plate, and the axis of the spline shaft coincides with the axis of the cylinder block.

9. A high pressure manual pump usable in a closed hydraulic system according to claim 1, further comprising a large bearing housing and a small bearing housing; the large bearing seat and the small bearing seat are respectively arranged at the bottoms of the angular contact ball bearing and the deep groove ball bearing, and grooves for installing sealing rings are formed in the inner ring and the outer ring of the large bearing seat and the small bearing seat and are used for sealing oil.