CN114718831A

CN114718831A - High-pressure manual pump for closed hydraulic system

Info

Publication number: CN114718831A
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: 2022-07-08
Anticipated expiration: 2042-03-30
Also published as: CN114718831B

Abstract

The invention discloses a high-pressure manual pump for a closed hydraulic system, which is designed to ensure reliable transmission of the manual pump under the condition of high-pressure load. Through the special design of the flow passage block, the oil supplementing and filling function without stopping the machine can be realized for the leaked oil in the closed hydraulic system and the closed system in the positive and negative rotation arbitrary working process. The manual pump can be applied to a high 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 design of manual hydraulic pumps, in particular to a high-pressure manual pump for a closed hydraulic system.

Background

The hydraulic pump is used as an important power element in the industry at present, is widely applied, comprises aerospace, walking vehicles, mine equipment and the like, 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, in order to ensure the reliability of the system, a set of reliable manual standby system is often required to be arranged for guarantee, and in order to cover various working conditions, the flow, the pressure and the volume of the manual pump are also required to be higher and higher at present.

Disclosure of Invention

Aiming at a closed hydraulic system, a novel manual hydraulic pump design is provided, the harsh requirements on flow and pressure can be met under various complex application environments, meanwhile, the quick switching of forward and reverse work can be realized, the compensation effect on the lateral force of a plunger can be realized through a tilting tray structure, the faults of overturning, abrasion and the like 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 function of the closed system in the forward and reverse random working process can be realized, the novel manual hydraulic pump can be used as a reliable main system oil supply pump or a standby system power source, and the novel manual hydraulic pump design is applied to the forward and reverse rotation of a hydraulic cylinder or a hydraulic motor.

In order to realize the above functions and performance requirements, the technical scheme adopted by the invention is as follows: a high-pressure manual pump for a closed hydraulic system comprises a rocking handle, a front end cover, an angular contact ball bearing, a swash plate, a rolling steel ball, a plunger, a spline shaft, a deep groove ball bearing, a cylinder body, a shell and a runner block, wherein the rocking handle is arranged on the front end cover;

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 swash plate is connected with the spline shaft through an involute spline to realize power transmission, and a rolling steel ball motion track is designed on the working surface of the swash plate; the circle center distribution of the track radius is superposed with the surface of the swash 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; the cylinder body is provided with plunger holes which are uniformly distributed, the plungers are arranged in the plunger holes of the cylinder body, the axis of the plungers is parallel to the axis of the cylinder body, and the tops of the plungers are provided with spherical grooves for installing rolling steel balls; when the device works, one half of the rolling steel balls are positioned in a spherical groove at the top of the plunger, the other half of the rolling steel balls are positioned in a rolling steel ball track of the swash plate, the rolling steel balls are in a linear contact state with a working surface of the swash plate and in a surface contact state with the spherical groove of the plunger, and the steel balls are always constrained in the track to move 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, 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-low pressure oil way of the closed hydraulic system.

Furthermore, the bottom surface of the swash plate is perpendicular to the axial line of the swash plate, a certain included angle is formed between the working surface and the bottom surface of the swash plate, the included angle is determined according to the displacement of the hand pump, and in the working process, the swash plate and the rolling steel balls are in a linear contact state, so that the radial force in the motion of the plunger can be overcome, and the reliable power transmission is ensured.

Furthermore, the two hydraulic control two-position three-way valves are installed in parallel inside the flow channel block and used for recycling leaked oil in the closed hydraulic system by the manual pump and supplementing and charging oil to the closed system without stopping in any working process of forward and reverse rotation.

Furthermore, the plunger is of a cylindrical revolving body structure, the inside of the plunger is a cavity and 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 the plunger hole; the outer side of the plunger is provided with a kidney-shaped groove for distributing oil in high and low pressure cavities.

Furthermore, the cylinder body is installed inside the shell and is tightly pressed in the inner cavity of the shell through the rear end cover, 8 plunger holes are uniformly distributed in the cylinder body along the circumference, and the axes of the plunger holes are parallel to the axis of the cylinder body. An upper flow passage and a lower flow passage are arranged in each plunger hole and are matched with the kidney-shaped groove to realize flow distribution, and the upper flow passage of each plunger hole is communicated with the lower flow passage of the other plunger hole with the interval of 1 according to the clockwise or anticlockwise sequence. The cylinder body side is provided with the runner groove that is used for fluid business turn over, runner groove and 8 plunger hole lateral walls all communicate, and the cylinder body side still is provided with 3 recesses that are used for installing the sealing washer.

Furthermore, a step retainer ring is mounted on the spline shaft and used for limiting the axial direction of the swash plate, and the axis of the spline shaft is overlapped 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 mounting sealing rings are respectively arranged on the inner ring and the outer ring of the large bearing seat and the small bearing seat, so that oil can be sealed.

The structure principle is as follows: the manual pump spline shaft is rotated by shaking the rocking handle, the spline shaft further drives the swash plate to rotate, the plungers are firmly pressed on the working surface of the swash plate through the rolling steel balls due to the pressing spring force at the bottoms of the plungers, the swash plate has a certain inclination angle, the plungers perform reciprocating linear motion in plunger cavities inside the cylinder body along with the rotation of the swash plate, the flow distribution design of the plungers and the cylinder body is combined, each plunger finishes one oil suction and discharge process every time the swash plate rotates for one circle, as the pressure in the plunger cavities increases, hydraulic pressure force acts on the angular contact ball bearings through the plungers, the rolling steel balls, the swash plate and the stepped retainer rings, the steel balls are in spherical contact with the plungers and are in line contact with a track on the swash plate, relative to point contact, the track surface can offset partial plunger lateral force, and can still keep good lubrication and stress states under the action of larger hydraulic pressure force, the friction degree of the plunger is reduced, and the service lives of the plunger and the swash plate are prolonged.

The high-pressure manual pump for the closed hydraulic system has the advantages that: the plunger has the advantages of compact structure, small outlet flow pulsation, strong anti-overturning capacity of the plunger, large axial bearing capacity, small friction loss, simple structure and the like, realizes the 'line-surface' power transmission by adopting a special swash plate structure and a rolling steel ball design, and prolongs the service life of core parts. And the flow channel block adopts the parallel design of two hydraulic control two-position three-way valves, so that the manual pump has the functions of recycling leaked oil and supplementing oil to an external system under the forward and reverse working conditions, and has great use value in important fields such as aerospace, mining machinery and the like.

Drawings

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

Fig. 1 is a schematic view of the entire appearance of a high-pressure manual pump that can be used in a closed hydraulic system.

Fig. 2 is a schematic view of an assembly structure of a high-pressure hand pump which can be used in a closed hydraulic system.

FIG. 3 is a forward detail view of the swash plate.

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

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

Fig. 6 is a schematic diagram of a hydraulic flow path of the flow path block.

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

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

FIG. 9 is a simplified force diagram of a plunger swashplate steel ball.

Reference numerals: 1. the hydraulic control type hydraulic control device comprises a rocking handle, a front end cover, a large bearing seat, a large angular contact ball bearing, a step retainer ring, a swash plate, a rolling steel ball, a plunger, a pressing spring, a spline shaft, a deep groove ball bearing, a small bearing seat, a cylinder body, a shell, a spring base, a rear end cover, a flow passage block, a connecting block, a first hydraulic control two-position three-way valve, a second hydraulic control two-position three-way valve and a check valve, wherein the rocking handle is 2, the front end cover is 3, the large bearing seat is 4, the angular contact ball bearing is 5, the step retainer ring is 6, the swash plate is 7, the rolling steel ball is 8, the pressing spring is 9, the spline shaft is 10, the deep groove ball bearing is 11, the small bearing seat is 12, the cylinder body is 13, the shell is 14, the spring base is 15, the rear end cover is 16, the flow passage block is 17, the connecting block is 18, the 17.1, the first hydraulic control two-position three-way valve, the 17.2, the second hydraulic control two-position three-way valve and the check valve is 17.3.

Detailed Description

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

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

shell

14, 8 plungers 8 are correspondingly arranged in 8 plunger holes of the cylinder body respectively, a compression spring 9 is arranged at the bottom of each plunger 8, the compression spring 9 is divided into an upper spring part and a lower spring part, the middle parts of the upper spring part and the lower spring part are connected together through a connecting block 18, and a spring base 15 is used for sealing the bottoms of the plunger holes; a kidney-shaped groove is designed on the outer side of the plunger piston and used for distributing oil liquid in high and low pressure cavities, the top of the plunger piston 8 is used for installing a rolling steel ball 7, the rolling steel ball 7 is pressed in a steel ball track on the surface of the swash plate 6 through the plunger piston 8 under the action of a compression spring 9, the steel ball is in surface contact with the spherical groove of the plunger piston and is in line contact with the steel ball track of the swash plate 6; the swash plate 6 is installed 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 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 installed at the bottom of a bearing and used for axial sealing, the front end cover 2 is installed on a shell 14 through bolts, a rocking handle 1 is installed 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 that the rocking handle 1 is manually rotated to drive but is not limited to manual driving.

The working principle is as follows: the hand pump distributes flow through the special structural design of a cylinder body and plungers, as shown in fig. 7, the axial lines of 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 axial line of the cylinder body 13, the plungers are uniformly distributed in the plunger holes, a swash plate 6 has a certain inclination angle beta, when the crank 1 drives the spline shaft 10 to rotate, the spline shaft 10 drives the swash plate 6 to rotate, the plungers can do reciprocating linear motion in the plunger cavities of the cylinder body 13 due to the pressing force of the swash plate 6 on 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-pressing oil motion state, and 3 plungers are in an upward oil absorption state, every time the rocking handle 1 rotates for a circle, each plunger 8 realizes the oil suction and discharge process once.

When the plunger 8 bottom produces high pressure fluid, the plunger 8 bottom will receive certain hydraulic pressure, this hydraulic pressure force is acted on sloping cam plate 6 through rolling steel ball 7, the steel ball is the sphere contact with plunger 8, be the line contact with sloping cam plate 6, the effort of sloping cam plate 6 to the steel ball can be decomposed into axial and radial, wherein radial effort bears through the steel ball track on sloping cam plate 6, avoided the plunger to receive the moment of overturning, the plunger atress situation has been improved, improve lubricated characteristic and bearing capacity, final axial direction's hydraulic pressure will be transmitted to angular contact ball bearing 4 through ladder retaining ring 5 on.

The rocking handle 1 is rotated, when the A mouthful runner is gone out oil, under the high-pressure chamber pressure effect, two three-way valve spools of liquid accuse in the runner block 17 are promoted, the leakage oil and the oil supply return circuit of casing 14 inner chamber pass through two three-way valve of liquid accuse and B mouthful low pressure runner intercommunication, when changing rocking handle 1 rotation direction, the oil inlet and outlet switch, the B mouthful runner is gone out oil, two three-way valve spools of liquid accuse position also changes under the pressure oil effect this moment, the leakage oil and the oil supply return circuit of casing 14 inner chamber pass through two three-way valve of liquid accuse and A mouthful runner intercommunication. The oil supplementing port is always communicated with the low-pressure port in the pump system, so that the oil supplementing is allowed to be performed on the system under the condition that the manual pump rotates forwards and backwards and any load pressure is achieved.

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

the communication mode of the inner runners of each plunger hole on the cylinder body 13 is that a first plunger hole upper runner 13.1-1 is communicated with a third plunger hole lower runner 13.3-2, a second plunger hole upper runner 13.2-1 is communicated with a fourth plunger hole lower runner 13.4-2, a third plunger hole upper runner 13.3-1 is communicated with a fifth plunger hole lower runner 13.5-2, a fourth plunger hole upper runner 13.4-1 is communicated with a sixth plunger hole lower runner 13.6-2, the fifth plunger hole upper flow channel 13.5-1 is communicated with the seventh plunger hole lower flow channel 13.7-2, the sixth plunger hole upper flow channel 13.6-1 is communicated with the eighth plunger hole lower flow channel 13.8-2, the seventh plunger hole upper flow channel 13.7-1 is communicated with the first plunger hole lower flow channel 13.1-2, and the eighth plunger hole upper flow channel 13.8-1 is communicated with the second plunger hole lower flow channel 13.2-2. Because the A, B port on the cylinder block 13 cooperates with waist-shaped groove of the piston plunger, when the piston plunger is between upper limit position and full stroke midpoint, the port of the up-flow in the cavity of the piston plunger communicates with A port on the cylinder block 13 through the waist-shaped groove, B port in the cavity of the piston plunger is closed by the piston plunger; when the plunger piston is positioned between the full stroke middle point and the lower limit position, the A port in the plunger piston cavity is closed by the plunger piston, and the upstream port opening is communicated with the B port 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 to press oil, the bottom first plunger hole lower flow passage 13.1-2 is communicated with the seventh plunger hole upper flow passage 13.7-1, because the plunger in the first plunger hole 13.1 is 90 degrees different from the plunger in the seventh plunger hole 13.7, when the plunger in the first plunger hole 13.1 presses oil downwards, the plunger in the seventh plunger hole 13.7 is always positioned between the upper limit position and the full stroke middle point, at the moment, the upper flow passage in the plunger cavity in the seventh plunger hole 13.7 is communicated with the A port in the cylinder body 13, and pressure oil generated at the bottom of the plunger in the first plunger hole 13.1 flows out from the A port in the plunger cavity in the seventh plunger hole 13.7 through the first plunger hole lower flow passage 13.1-2-the seventh plunger hole upper flow passage 13.7-1; when the plunger in the first plunger hole 13.1 absorbs oil upwards from the lower limit position, the position of the plunger in the seventh plunger hole 13.7 is always between the full stroke midpoint and the lower limit position, at the moment, an upper flow passage in the 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 flow passage 13.1-2-the seventh plunger hole upper flow passage 13.7-1 to finish the oil filling process, and the analysis principles of the working processes of other plungers are the same. At the moment, the port A of the pump is a high-pressure oil outlet, the port B of the pump is a low-pressure oil inlet, and the valve core of the hydraulic control two-position three-way valve in the flow passage block 17 is pushed under the action of high-pressure oil at the port A, so that oil leakage inside the shell 14 and an external oil supplementing flow passage are communicated with the low-pressure oil suction port B.

When the rocking handle 1 is rotated reversely, in the process that the plunger in the first plunger hole 13.1 presses oil downwards from the upper limit position, the position of the plunger in the seventh plunger hole 13.7 is always between the full stroke midpoint and the lower limit position, at the moment, an upper flow passage in the plunger cavity in the seventh plunger hole 13.7 is communicated with a port B on the cylinder body 13, and pressure 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 first plunger hole lower flow passage 13.1-2-a seventh plunger hole upper flow passage 13.7-1 flow passage; when the plunger in the first plunger hole 13.1 absorbs oil upwards from the lower limit position, the position of the plunger in the seventh plunger hole 13.7 is always between the upper limit position and the full stroke midpoint, at the moment, an upper flow passage in the cavity of the plunger in the seventh plunger hole 13.7 is communicated with an 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 first plunger hole lower flow passage 13.1-2-the seventh plunger hole upper flow passage 13.7-1 to finish the oil filling process, and the analysis principles of the working processes of other plungers are the same. At the moment, the port B of the pump is a high-pressure oil outlet, the port A of the pump is a low-pressure oil inlet, and the position of a valve core of the hydraulic control two-position three-way valve in the flow passage block 17 is changed under the action of high-pressure oil at the port B, so that oil leaking inside the shell 14 and an external oil supplementing flow passage are communicated with a low-pressure oil suction port A.

Finally, it should be noted that the above description is only one specific application example of the present invention, and is not intended to limit the present invention, and other application examples similar to the basic principle of the present invention should also belong to the protection scope of the present invention.

Claims

1. The utility model provides a can be used to high-pressure hand pump of closed hydraulic system which characterized in that: the device comprises a rocking handle, a front end cover, an angular contact ball bearing, a swash plate, rolling steel balls, a plunger, a spline shaft, a deep groove ball bearing, a cylinder body, a shell and a runner block;

the flow channel 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 channel block, 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-low pressure oil way of the closed hydraulic system.

2. A high pressure hand pump for use in a closed hydraulic system as claimed in 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 by the displacement of the hand pump.

3. The high-pressure manual pump for the closed hydraulic system as claimed in claim 1, wherein during operation of the high-pressure manual pump, the swash plate and the rolling steel balls are in line contact, so that radial force generated during movement of the plunger is overcome, and power transmission is ensured.

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

5. The high-pressure manual pump applicable to the closed hydraulic system according to claim 1, wherein the plunger is of a cylindrical revolving body structure, the inside of the plunger is a cavity for mounting a compression spring, the other end of the compression spring is mounted on a spring base, and the spring base is used for sealing the bottom of a plunger hole; the outer side of the plunger is provided with a kidney-shaped groove for distributing oil in high and low pressure cavities.

6. The high-pressure manual pump applicable to the closed hydraulic system as claimed in claim 1, wherein the cylinder body is mounted inside the housing and is tightly pressed in the inner cavity of the housing through a rear end cover, 8 plunger holes are uniformly distributed along the circumference in the cylinder body, and the axes of the plunger holes are parallel to the axis of the cylinder body.

7. A high-pressure manual pump for a closed hydraulic system according to claim 6, characterized in that an upper flow passage and a lower flow passage are provided in each plunger hole to match with the kidney-shaped groove to realize flow distribution, and the upper flow passage of each plunger hole is communicated with the lower flow passage of another plunger hole with a spacing of 1 in a clockwise or counterclockwise sequence.

8. A high-pressure manual pump for a closed hydraulic system according to claim 6, characterized in that 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 further provided with 3 grooves for installing sealing rings.

9. The high pressure hand pump for closed hydraulic system as claimed in claim 1, wherein the spline shaft has a stepped retainer ring mounted thereon for swash plate axial retention, the spline shaft axis coinciding with the cylinder axis.

10. The high pressure hand pump for a closed hydraulic system according to claim 1, further comprising 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 mounting sealing rings are respectively arranged on the inner ring and the outer ring of the large bearing seat and the small bearing seat, so that oil can be sealed.