CN117028198A

CN117028198A - Pump head and oil gas recovery pump

Info

Publication number: CN117028198A
Application number: CN202311097689.XA
Authority: CN
Inventors: 尚佳成; 贺振江; 邹骏; 张凯
Original assignee: Vader Road Service Station Equipment Shanghai Co ltd
Current assignee: Vader Road Service Station Equipment Shanghai Co ltd
Priority date: 2023-08-29
Filing date: 2023-08-29
Publication date: 2023-11-10

Abstract

The invention discloses a pump head and an oil gas recovery pump, wherein the pump head comprises: the shell is provided with a hollow accommodating cavity, and a first air inlet and a first air outlet are formed in the shell; an air inlet channel communicated with the first air inlet and an air outlet channel communicated with the first air outlet are arranged in the shell; the piston devices are arranged in the accommodating cavity of the shell, and the number of the piston devices is two; the piston device comprises a piston assembly and a cylinder body, part of the piston assembly is positioned in the cylinder body, and the piston assembly is arranged to move along the axial direction of the cylinder body; the valve plate assembly comprises a valve plate, the valve plate is positioned on one side of the cylinder body, the valve plate is in sealing connection with one end face of the cylinder body, and a second air inlet and a second air outlet are formed in the valve plate; the transmission mechanism is arranged in the accommodating cavity of the shell and is used for driving the piston assembly to move along the axial direction of the cylinder body towards a direction approaching to or away from the valve plate; the transmission mechanism is positioned between the two cylinder bodies, and the two cylinder bodies are symmetrically arranged by the rotation axis of the transmission mechanism.

Description

Pump head and oil gas recovery pump

Technical Field

The invention relates to the technical field of oil gas recovery, in particular to a pump head and an oil gas recovery pump.

Background

During the transfer of gasoline from the reservoir to the vehicle tank, oil and gas are produced in each storage link. For example, in the process of filling gasoline into an automobile oil tank from a filling station, the gasoline is filled into the automobile oil tank to replace the volatile oil gas in the original space in the automobile oil tank, and the oil gas is discharged to the environment in the oiling process, so that the environment is easily polluted, the great resource waste is caused, and meanwhile, the serious potential safety hazard of easily causing fire and explosion exists.

In order to change the environmental pollution and energy waste caused by oil gas, oil gas recovery systems are commonly adopted in all gas stations, oil gas is recovered into an underground oil storage tank when a vehicle is refueled, and in order to realize oil gas recovery, an oil gas vacuum pump needs to be installed on an oil gas recovery pipeline in series before entering the underground oil storage tank. However, the single piston pump adopted at present has relatively large piston stroke, and the generated vibration and noise are large.

Disclosure of Invention

The invention aims to provide a pump head and an oil gas recovery pump.

A first aspect of the invention provides a pump head comprising: the shell is provided with a hollow accommodating cavity, a first air inlet and a first air outlet are arranged on the shell, and the first air inlet and the first air outlet are positioned in the same plane; an air inlet channel communicated with the first air inlet and an air outlet channel communicated with the first air outlet are arranged in the shell, the axes of the air inlet channel and the air outlet channel are approximately parallel, the axes of the first air inlet and the first air outlet are approximately parallel, and the axes of the air inlet channel and the first air inlet are approximately vertical; the piston devices are arranged in the accommodating cavity of the shell, and the number of the piston devices is two; the piston device comprises a piston assembly and a cylinder body, wherein part of the piston assembly is positioned in the cylinder body, and the piston assembly is arranged to move along the axial direction of the cylinder body; the valve plate assembly comprises a valve plate, the valve plate is positioned on one side of the cylinder body, the valve plate is in sealing connection with one end face of the cylinder body, and a second air inlet and a second air outlet are formed in the valve plate; the drive mechanism, it sets up in the hold intracavity of casing, drive mechanism includes: the crankshaft assembly and the transmission shaft are positioned on the same axis, the crankshaft assembly is positioned on one side of the transmission shaft, and the transmission shaft drives the crankshaft assembly to rotate; the piston assembly is sleeved on the crankshaft assembly, so that the transmission mechanism drives the piston assembly to move along the axial direction of the cylinder body in a direction approaching to or separating from the valve plate; the transmission mechanism is positioned between the two cylinders, the two cylinders are symmetrically arranged with the rotation axis of the transmission mechanism, and the axes of the two cylinders are the same and are approximately perpendicular to the rotation axis of the transmission mechanism; the rotation axis of the transmission mechanism is approximately parallel to the axis of the first air inlet; the oil gas sequentially passes through the first air inlet and the air inlet channel, is respectively led into the cylinder body through the second air inlet in two paths, respectively enters the air outlet channel through the second air outlet, and is converged in the air outlet channel to enter the first air outlet.

A second aspect of the invention provides an oil and gas recovery pump comprising: the pump head; one end of the connecting shaft device is fixedly connected with the transmission mechanism; the motor comprises a connecting end cover, wherein the connecting end cover is fixedly connected with the shell; and an output shaft of the motor is fixedly connected with the other end of the connecting shaft device.

The technical scheme of the invention has the following beneficial technical effects:

1. in the embodiment of the invention, the vacuumizing function is realized by adopting two opposite piston pumps, so that the vacuum pump has the characteristic of strong vacuumizing capability, can reach higher vacuum degree, and provides sufficient vacuum margin for keeping the gas-liquid ratio stable; and the double pistons share the vacuumizing process, one piston of the pump head vacuumizes while the other piston exhausts in the running process, and the transmission mechanism can generate two vacuumizing actions every time when rotating for one circle.

2. In the embodiment of the invention, the first air inlet and the first air outlet are positioned on the same side of the shell and face the same direction, so that pipelines are conveniently arranged in the installation process.

3. In the embodiment of the invention, the reinforcing sheet is overlapped on one side of the opening direction of the valve sheet, so that the valve sheet can be supported in the valve sheet opening state, and the elastic force for closing the valve sheet can be increased; when the valve plate is in a closed state, the valve plate can be pressed tightly, so that the valve plate is more tightly attached to the valve plate, and the sealing performance is improved; therefore, the thickness and rigidity of the valve plate can be effectively reduced, the elasticity of the valve plate is increased, the vacuum degree consumed in the air inlet and exhaust processes can be further reduced, more ineffective power consumed by the oil gas recovery pump when the one-way valve is opened is avoided, and accordingly the power of the matched motor can be reasonably reduced.

4. In the embodiment of the invention, a plurality of reinforcing sheets are added to increase the opening pressure; or thinning and canceling the reinforcing sheet to reduce the operating power of the oil gas recovery pump; thus, the oil gas recovery pump can be conveniently debugged and used, and the use requirements of more users are met.

5. In the embodiment of the invention, the power consumption in the operation process of the oil gas recovery pump is reduced by adopting the ultrathin valve plate, the power of a matched motor is reduced, and the weight of the whole engine can be reduced.

6. In the embodiment of the invention, when the side wall of the piston ring is in a horn shape, the piston ring slides along the inner wall of the cylinder body, and the side wall at the large end of the piston ring is attached to the inner wall of the cylinder body and is extruded, the piston ring can be slightly contracted and deformed inwards, so that the friction resistance between the piston ring and the cylinder body and the mutual abrasion caused by the friction resistance are reduced, the abrasion of the piston ring can be delayed, the cylinder body is not easy to be rubbed and leaked, the service life of a piston device can be prolonged, the vacuum degree in the cylinder can be effectively maintained, and the air return capacity of the oil gas recovery pump is improved. The piston ring has the characteristics of wear resistance and self-lubricating capability, so that the friction power consumption generated in the working process can be reduced, and the service life of the piston ring can be prolonged; the surface of the cylinder body is provided with a wear-resistant coating, so that the service life of the cylinder body can be prolonged.

Drawings

FIG. 1 is a schematic cross-sectional view of a pump head according to a first embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of a pump head according to a second embodiment of the present invention;

fig. 3 is a schematic cross-sectional structure of a housing according to a third embodiment of the present invention;

fig. 4 is a partial schematic structural view of a pump head according to a fourth embodiment of the present invention;

fig. 5 is a schematic perspective view of a pump head according to a fifth embodiment of the present invention;

fig. 6 is a schematic perspective view of a gland according to a sixth embodiment of the present invention;

fig. 7 is a schematic structural view of a valve plate assembly according to a seventh embodiment of the present invention;

fig. 8 is a schematic structural view of a valve plate according to an eighth embodiment of the present invention;

fig. 9 is a schematic cross-sectional structure view of a valve plate assembly according to a ninth embodiment of the present invention;

fig. 10 is a schematic perspective view of a check valve according to a tenth embodiment of the present invention;

fig. 11 is a partial schematic structural view of a valve plate assembly according to an eleventh embodiment of the present invention;

fig. 12 is a schematic cross-sectional structure of a piston device according to a twelfth embodiment of the present invention;

FIG. 13 schematically illustrates a schematic structural view of a piston ring;

FIG. 14 schematically illustrates a structural schematic view of the crank axle;

Fig. 15 schematically shows a schematic structural view of a crank;

FIG. 16 schematically illustrates a schematic structural view of a weight;

fig. 17 is a schematic structural view of a connecting end cap according to a thirteenth embodiment of the present invention;

fig. 18 is a schematic structural view of a connecting end cap according to a fourteenth embodiment of the present invention;

fig. 19 is a schematic structural view of a connection end cap according to a fifteenth embodiment of the present invention;

fig. 20 is a schematic structural view of a coupling device according to a sixteenth embodiment of the present invention;

FIG. 21 is a schematic structural view of an oil and gas recovery pump according to a seventeenth embodiment of the present invention;

FIG. 22 is a schematic perspective view of an oil and gas recovery pump according to an eighteenth embodiment of the present invention;

reference numerals:

10. a housing; 11. a first air inlet; 12. a first air outlet; 13. an air intake passage; 14. an air outlet channel; 15. a gland; 101. a first mounting flange; 102. a first groove; 103. a first mounting post; 104. a second mounting post; 105. a first threaded hole; 106. a second threaded hole; 107. a mounting boss; 151. a first cavity; 152. a second boss; 153. a second cavity;

20. a piston device; 21. a cylinder; 22. a piston assembly; 23. a first hole; 24. a second hole; 25. a bump; 221. a pressing plate; 223. a support body; 224. a shaft sleeve; 225. piston rings;

30. A valve plate assembly; 31. a valve plate; 32. a one-way valve; 33. a gasket; 34. a pressure release valve; 311. a second air inlet; 312. a second air outlet; 313. a first boss; 314. a transition hole; 315. a second groove; 316. a pressure relief hole; 317. a first air outlet hole; 318. a second mounting hole; 321. a valve plate; 322. a reinforcing sheet; 341. a pressure regulating nut; 342. a spring; 343. steel balls;

40. a transmission mechanism; 41. a crank shaft; 42. a crank; 43. balancing weight; 44. a transmission shaft; 45. a first screw; 46. a second screw; 411. a positioning part; 412. a long axis section; 413. cutting a plane; 421. a connection part; 422. a shaft shoulder; 423. a third mounting hole; 424. a lightening hole; 425a, through slot one; 425b, through slot two; 431. a fourth mounting hole; 432. a weight adjustment hole;

50. connecting an end cover; 51. a connecting body; 52. a motor connector; 53. a pump head connector; 54. positioning the connecting part; 55. arc-shaped openings; 541. a first lug; 542. a second lug; 543. a third hole; 544. a fourth hole;

60. a coupling device; 61. a first coupling; 62. a second coupling; 63. a rubber gasket; 611. a motor connecting sleeve; 612. a first flange; 613. a first branch claw; 621. a pump head connecting sleeve; 622. a second flange; 623. a second branch claw;

70. A motor; 71. a housing; 72. a bump; 73. an output shaft.

Detailed Description

The objects, technical solutions and advantages of the present invention will become more apparent by the following detailed description of the present invention with reference to the accompanying drawings. It should be understood that the description is only illustrative and is not intended to limit the scope of the invention. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the present invention.

The oil gas recovery system mainly comprises an oil gun, a rubber tube, an oil gas separation joint and a vacuum recovery pump. The oil gun can be provided with an oil-gas recovery function, two channels for oil filling and oil-gas recovery are arranged in the rubber tube, the oil-gas separation joint separates an oil way from an oil-gas recovery gas way, two ends of the rubber tube are respectively connected with the oil gun and the oil-gas separation joint, two ends of the oil way pipeline are respectively connected with the oil-gas separation joint and an outlet of an underground oil storage tank, two ends of the oil-gas recovery pipeline are respectively connected with the oil-gas separation joint and an inlet of the underground oil storage tank, and an oil-gas vacuum pump is arranged on the oil-gas recovery pipeline in series, so that oil gas is recovered to the underground oil storage tank through the oil-gas recovery system. However, the single piston pump adopted at present has relatively large piston stroke, and the generated vibration and noise are large.

In view of this, a first aspect of the present invention provides a pump head, as shown in fig. 1 to 13, comprising: housing 10, piston assembly 20, valve plate assembly 30, and transmission mechanism 40. The shell 10 is provided with a hollow accommodating cavity, the shell 10 is provided with a first air inlet 11 and a first air outlet 12, and the first air inlet 11 and the first air outlet 12 are positioned in the same plane; an air inlet channel 13 communicated with the first air inlet 11 and an air outlet channel 14 communicated with the first air outlet 12 are arranged in the shell 10, the axes of the air inlet channel 13 and the air outlet channel 14 are parallel to each other, the axes of the first air inlet 11 and the first air outlet 12 are parallel to each other, and the axes of the air inlet channel 13 and the first air inlet 11 are perpendicular to each other; a piston device 20 provided in the housing chamber of the housing 10, the piston device being provided in two; the piston device comprises a piston assembly and a cylinder 21, wherein part of the piston assembly is positioned in the cylinder 21, and the piston assembly is arranged to move along the axial direction of the cylinder 21; the valve plate assembly 30 comprises a valve plate 31, the valve plate 31 is positioned on one side of the cylinder body 21, the valve plate 31 is in sealing connection with one end face of the cylinder body 21, and a second air inlet and a second air outlet are formed in the valve plate 31; a transmission mechanism 40 disposed in the accommodating cavity of the housing 10, the transmission mechanism may include: the crankshaft assembly and the transmission shaft are positioned on the same axis, the crankshaft assembly is positioned on one side of the transmission shaft, and the transmission shaft drives the crankshaft assembly to rotate; the piston assembly is sleeved on the crankshaft assembly, so that the transmission mechanism 40 drives the piston assembly to move along the axial direction of the cylinder body 21 towards or away from the valve plate 31; the transmission mechanism 40 is located between the two cylinders 21, the two cylinders 21 are symmetrically arranged with the rotation axis of the transmission mechanism 40, and the axes of the two cylinders 21 are the same axis and perpendicular to the rotation axis of the transmission mechanism 40; the rotation axis of the transmission mechanism 40 and the axis of the first air inlet 11 are parallel to each other; the oil gas sequentially passes through the first air inlet 11 and the air inlet channel 13, is respectively led into the cylinder body 21 through the second air inlet, respectively enters the air outlet channel 14 through the second air outlet, and is converged in the air outlet channel 14 to enter the first air outlet 12. The two ends of the shell 10 are provided with openings, so that the cylinder body 21 can be conveniently installed from the two ends of the shell 10, a groove can be formed in the shell 10, one end of the cylinder body 21 is embedded in the groove, the other end of the cylinder body 21 can be embedded in the installation groove of the valve plate 31, the valve plate 31 can be fixed on the shell 10, a sealing ring can be embedded in the installation groove of the valve plate 31, the top of the cylinder body 21 extrudes the sealing ring, and the sealing ring is deformed to seal oil gas entering the cylinder body 21 and prevent leakage from a connecting part; the piston devices are arranged on two sides of the transmission mechanism 40 and are symmetrically arranged on the rotation axis of the transmission mechanism 40, so that the structure of the linearly opposite pistons is more compact, and the volume of the pump head is relatively reduced; the first air inlet 11 and the first air outlet 12 are positioned on the same side of the shell 10 and face the same direction, so that pipelines are conveniently arranged in the installation process; the axes of the first air inlet 11 and the first air outlet 12 are parallel to the rotation axis of the transmission mechanism 40, that is, the planes of the first air inlet 11 and the first air outlet 12 are opposite to the motor mounting surface, the air inlet channel 13 and the air outlet channel 14 can be arranged to extend along the longitudinal direction of the shell 10 and respectively communicate with the second air inlet 311 and the second air outlet 312 on the valve plate 31 at the top (or bottom) of the cylinder 21, so that the oil gas enters the air inlet channel 13 through the first air inlet 11, and is respectively introduced into the cylinder 21 through the second air inlet 311 on the valve plate 31, respectively enters the air outlet channel 14 through the second air outlet 312, and is converged into the first air outlet 12 in the air outlet channel 14, and the first air outlet 12 is communicated with the oil gas recovery pipeline to recover the oil gas to the underground oil storage tank, and the arrows shown in fig. 2 are the flowing directions of the oil gas; therefore, the whole machine has compact structure and reasonable arrangement; the double pistons share the vacuumizing process, and when the transmission shaft rotates, the crankshaft assembly is driven to rotate, so that the piston assembly is driven to reciprocate; and the directions of the two opposite pistons are the same, namely, one piston is vacuumized and the other piston is exhausted when the pump head is in operation, and the transmission mechanism 40 can generate two vacuumization actions when rotating for each circle.

In an exemplary embodiment, the housing 10 may be provided as a casting, and the inlet passage 13 and the outlet passage 14 are common to two opposed piston devices, and thus the inlet passage 13 and the outlet passage 14 may be provided as a part of the casting, and the inner diameters of the inlet passage 13 and the outlet passage 14 may be set to 10mm, for example.

In some embodiments, the first air inlet 11 and the first air outlet 12 are respectively located at two sides of the transmission mechanism 40, and the height of the first air inlet 11 is higher than that of the first air outlet 12; the plane in which the first air inlet 11 and the first air outlet 12 are located is opposite to the motor mounting surface. The directions of the first air inlet 11 and the first air outlet 12 are parallel to the rotation axis direction of the transmission mechanism 40 and face the same direction, and the heights of the first air inlet 11 and the first air outlet 12 are staggered, so that the installation of the oil gas recovery pipeline is facilitated, and the pipeline is reasonably arranged; in addition, when the pump head is installed, the first air inlet 11 is kept higher than the first air outlet 12, so that liquid can be conveniently discharged after the liquid is accidentally fed into the pump head. The shell 10 is provided with a protruding mounting boss 107, one end of the mounting boss 107, which is away from the shell 10, forms a motor mounting surface, the mounting boss 107 is provided with threaded holes which are distributed at intervals, so that a motor is mounted on the mounting boss 107 by adopting a threaded fastener, the mounting boss 107 can be hollow so that the connecting shaft device 60 can be mounted, and the mounting boss 107 can be provided with a plurality of long waist holes, which can reduce weight and dissipate heat.

In some embodiments, two ends of the housing 10 are respectively provided with a protruding first mounting flange 101, and an end surface of the first mounting flange 101 and an end surface of the housing 10 are both located on a first mounting surface, wherein the first mounting surface is parallel to the rotation axis of the transmission mechanism 40; the first mounting surface is provided with first threaded holes 105, and the first threaded holes 105 are circumferentially and alternately distributed along the accommodating cavity of the shell 10; the valve plate 31 is provided with a first through hole which is matched with the first threaded hole 105 so as to mount the valve plate 31 on the shell 10; the valve plate 31 is provided with a mounting groove, and one end of the cylinder 21 is inserted into the mounting groove. The end face of the first mounting flange 101 and the end face of the housing 10 are both located on the same plane, a column protruding into the accommodating cavity can be arranged on the inner wall of the housing 10, the column is arranged along the longitudinal direction of the housing 10, a first threaded hole is arranged in the column, and a mounting screw penetrates through the first through hole on the valve plate 31 and is screwed into the first threaded hole to mount the valve plate 31 on the housing 10; a groove can be formed in the shell 10, one end of the cylinder body 21 is embedded in the groove, the other end of the cylinder body 21 can be embedded in the mounting groove of the valve plate 31, a sealing ring can be embedded in the mounting groove of the valve plate 31, the top of the cylinder body 21 extrudes the sealing ring, so that the sealing ring is deformed to seal oil gas entering the cylinder body 21, and leakage from a joint is prevented; the fixation of the cylinder 21 and the sealing of the oil gas entering the cylinder 21 can be realized by the installation of the valve plate 31; meanwhile, the second air inlet and the second air outlet are formed in the valve plate 31 to respectively enter and discharge oil gas in the cylinder body 21, and the check valve 32 is fixed on the valve plate 31, so that the pump head is simple and compact in structure and easy to maintain.

In some embodiments, the pump head further comprises: a gland 15 fixedly connected to the first mounting flange 101; one side of the gland 15 is provided with a concave first cavity 151, and the opposite side of the gland 15 protrudes; the valve plate 31 is located in the first cavity 151, and the first cavity 151 communicates with the intake passage 13; the first mounting flange 101 is provided with second threaded holes 106, and the second threaded holes 106 are distributed at intervals along the circumferential direction of the first mounting flange 101; the gland 15 is provided with a second through hole which is matched with the second threaded hole 106 so as to mount the gland 15 on the first mounting flange 101; the circumferential distribution size of the second screw holes 106 is larger than the circumferential distribution size of the first screw holes 105; the first mounting surface is provided with a first groove 102, the first groove 102 surrounds the inner cavity of the shell 10, and the first groove 102 is positioned between the first threaded hole 105 and the second threaded hole 106; a first sealing ring is arranged in the first groove 102, and the end face of the gland 15 contacts with the first sealing ring to prevent oil gas in the accommodating cavity of the shell 10 from escaping to the external atmosphere. The gland 15 can be cast and molded, and the mounting screw passes through the second through hole on the gland 15 and is screwed into the second threaded hole 106 so as to mount the gland 15 on the first mounting flange 101, and simultaneously, the first sealing ring is extruded and deformed to realize the sealing of the joint, so that the oil gas in the accommodating cavity of the shell 10 is prevented from escaping to the external atmosphere; the valve plate 31 is located in the first cavity 151, and the first cavity 151 communicates with the intake passage 13, so that oil gas enters the first cavity 151 through the intake passage 13 and then enters the cylinder 21 through the second intake port.

In some embodiments, valve plate 31 is provided with a first boss 313, first boss 313 extending along a side facing away from cylinder 21; the second air outlet 312 penetrates through the first boss 313, a transition hole 314 is formed in the first boss 313, and the axis of the second air outlet 312 is parallel to the axis of the transition hole 314; a second groove is formed in a side plane, facing away from the cylinder body 21, of the first boss 313, the second groove is formed along the circumferential direction of the first boss 313, and the second air outlet 312 and the transition hole 314 are both located in the range of the second groove; a second sealing ring is arranged in the second groove; the first cavity 151 is internally provided with a second boss 152, the shape of the second boss 152 is matched with that of the first boss 313, the second boss 152 is internally provided with a concave second cavity 153, the second cavity 153 is communicated with the transition hole 314, and the check valve 32 at the second air outlet 312 is positioned in the second cavity 153; the second boss 152 contacts the second sealing ring to block oil and gas in the first cavity 151 and the second cavity 153 from flowing into each other. When the gland 15 is mounted on the first mounting flange 101, the second boss 152 presses the second sealing ring to realize sealing, so that oil gas in the first cavity 151 and the second cavity 153 can be prevented from flowing away from each other, and the oil gas in the cylinder 21 is pushed by the piston assembly to be discharged from the second air outlet 312 into the second cavity 153 to be released in pressure, so that the running power of the motor can be reduced.

In some embodiments, the outer side surface of the casing 10 is provided with a plurality of first mounting posts 103 which are distributed at intervals, and the first mounting posts 103 are used for mounting the pump head so as to fix the relative position of the pump head; alternatively, the outer side surface of the gland 15 is provided with a plurality of second mounting columns 104 which are distributed at intervals, and the second mounting columns 104 are used for mounting the pump head so as to fix the relative position of the pump head. The first mounting column 103 can be internally provided with a mounting threaded hole, and the end face of one end of the first mounting column 103, which faces away from the shell 10, forms the same mounting plane; similarly, a mounting threaded hole can be formed in the second mounting column 104, and the end face of one end of the second mounting column 104, which faces away from the gland 15, forms the same mounting plane; therefore, the pump head can be fixed on a plurality of planes such as the side face, the top or the bottom, and the like, so that the requirements of various actual use working conditions are met. In addition, ribs are provided on the outer side surface of the pressing cover 15 at intervals to increase the heat dissipation area.

In some embodiments, as shown in fig. 7-11, valve plate assembly 30 may specifically include: a valve plate 31 and a check valve 32. The valve plate 31 is positioned on one side of the cylinder body, and the valve plate 31 is in sealing connection with one end face of the cylinder body; the valve plate 31 is provided with a second air inlet 311 and a second air outlet 312, the second air inlet 311 is used for introducing oil gas into the cylinder body, and the second air outlet 312 is used for discharging the oil gas in the cylinder body; the check valve 32 is mounted on one side of the valve plate 31, and the check valve 32 is provided downstream in the direction in which the oil gas flows through the second inlet port 311 or the second outlet port 312; the check valve 32 includes a valve plate 321 and a reinforcing plate 322, the valve plate 321 covers the second inlet 311 or the second outlet 312, and the valve plate 321 is located between the reinforcing plate 322 and the valve plate 31; the oil gas is introduced into the cylinder body through the second inlet 311 and the check valve 32 in this order, and is discharged through the second outlet 312 and the check valve 32. A groove can be formed in the end face of one end of the cylinder body, a sealing ring is embedded in the groove, and when the valve plate 31 is fixed on the shell, the valve plate 31 compresses the sealing ring, so that the sealing ring is extruded and deformed, and oil gas entering the cylinder body is sealed, and the oil gas is prevented from escaping from the joint of the valve plate 31 and the end face of the cylinder body; when the piston moves up and down in the cylinder body, the piston ring is sealed with the inner wall of the cylinder body; the check valve 32 is used for controlling the one-way flow of the oil gas and preventing the oil gas from flowing reversely; for example, the check valve 32 at the second intake port 311 is set as a first check valve, and the check valve 32 at the second exhaust port 312 is set as a second check valve; when the piston moves in the cylinder body in a direction away from the valve plate 31, the cylinder body is vacuumized to form negative pressure, oil gas enters the cylinder body from the second air inlet 311, at the moment, the first one-way valve at the second air inlet 311 is opened, namely the valve plate 321 is sprung by the valve plate 31, and the second one-way valve at the second air outlet 312 is closed, namely the valve plate 321 is attached to the valve plate 31; when the piston moves in the cylinder body towards the direction close to the valve plate 31, oil gas in the cylinder body is discharged from the second air outlet 312, at the moment, the second one-way valve at the second air outlet 312 is opened, namely the valve plate 321 is sprung by the valve plate 31, and the first one-way valve at the second air inlet 311 is closed, namely the valve plate 321 is attached to the valve plate 31; by superposing the reinforcing sheet 322 on one side of the opening direction of the valve sheet 321, the valve sheet 321 can be supported in the opening state of the valve sheet 321, and the elastic force of the closing of the valve sheet 321 can be increased; when the valve plate 321 is in a closed state, the valve plate 321 can be pressed tightly, so that the valve plate 321 is more tightly attached to the valve plate 31, and the sealing performance is improved; therefore, the thickness and rigidity of the valve plate 321 can be effectively reduced, the elasticity of the valve plate 321 is increased, the vacuum degree consumed in the air inlet and air exhaust processes can be further reduced, more ineffective power consumed by the oil gas recovery pump when the one-way valve 32 is opened is avoided, and accordingly the power of a matched motor can be reasonably reduced.

In some embodiments, the thickness of the reinforcing sheet 322 is adjustable to adjust the amount of closing or opening pressure of the check valve 32; wherein the reinforcing sheets 322 include a plurality of reinforcing sheets 322, and the number of reinforcing sheets 322 is increased or decreased to adjust the closing or opening pressure of the check valve 32. The thickness of each reinforcing sheet 322 may be set to be different, and may include, for example, 0.05mm, 0.08mm, 0.1mm, 0.15mm, and the like; the thickness of each reinforcing sheet 322 may also be set to be the same, for example, 0.1mm; in practice, the reinforcing sheet 322 may be adjusted according to the requirement of closing or opening pressure of the check valve 32 of the oil and gas recovery pump, for example: reinforcing sheets 322 are added to increase the opening pressure; alternatively, the reinforcement blade 322 may be thinned and eliminated to reduce the operating power of the oil and gas recovery pump; thus, the oil gas recovery pump can be conveniently debugged and used, and the use requirements of more users are met.

In some embodiments, the valve plate 321 is provided in a sheet-like rectangular structure; the ratio of the length to the width of the valve plate 321 ranges from 2.5 to 1. Specifically, the sides corresponding to the length direction of the valve plate 321 are long sides, the sides corresponding to the width direction of the valve plate 321 are short sides, and the maximum dimension ratio of the long sides to the short sides can be set to be 5:2.

In some embodiments, the thickness of the valve plate 321 is set to 0.03mm-0.1mm; the valve plate 321 mainly plays a role in sealing, and can be made of a 7Cr27Mo2 thin steel sheet, a 2Cr13 or 0Cr17Ni4Cu4Nb thin steel sheet, a 0Cr15Ni7Mo2Al thin steel sheet or a PEEK thin sheet. The hardness of the valve plate 321 may be set to be in the range of HRC47-52, with a preferred hardness of the valve plate 321 being HRC50. The surface roughness of the valve plate 321 is required to be lower than Ra0.05 or Ra0.1. Preferably, the thickness of the valve plate 321 is 0.05mm or 0.08mm, and the valve plate 321 with smaller thickness can improve the sealing performance on the air inlet and the air outlet, and reduce the power consumption of air inlet and air outlet.

In some embodiments, the thickness of the reinforcing sheet 322 is set to 0.1mm-0.3mm. The reinforcing sheet 322 may specifically comprise PTFE or 304 stainless steel sheet; in the exemplary embodiment, the reinforcing sheet 322 is made of PTFE, and the thickness of the reinforcing sheet 322 may be 0.3mm. The reinforcing sheet 322 has a certain elasticity, and not only can provide support for the valve plate 321, but also can help to rebound and reset the valve plate 321.

In some embodiments, the width of the reinforcing sheet 322 is equal to or less than the width of the valve sheet 321; the length of the reinforcing sheet 322 is smaller than the length of the valve sheet 321.

In an exemplary embodiment, the length of the reinforcing sheet 322 is set to 0.5 to 0.8 times the length of the valve sheet 321; preferably, the length of the reinforcing sheet 322 may be set to 60% of the length of the valve sheet 321, which facilitates the opening and rebound reset of the valve sheet 321.

The valve block 321 is provided with a first through mounting hole, and the distance between the axis of the first mounting hole and the short side of the valve block 321 is 15% -20% of the length of the valve block 321. Similarly, the reinforcing piece 322 may be provided with the first mounting hole at the same position, the valve plate 31 may be correspondingly provided with a threaded hole, and a screw is screwed into the threaded hole through the first mounting hole, so as to stack and fix the valve plate 321 and the reinforcing piece 322 on the valve plate 31; when the piston moves in a direction away from the valve plate 31 after the valve plate 321 and the reinforcing plate 322 are locked by the screw, namely, vacuum is formed in the cylinder, the valve plate 321 of the first one-way valve takes the screw as a fulcrum, the other end of the valve plate 321 moves into the cylinder, so that the valve plate 31 is separated, and oil gas enters the cylinder; the position of the screw is reasonably set, so that the valve plate 321 is opened and rebound for resetting.

In some embodiments, valve plate assembly 30 further comprises: a spacer 33 located on a side of the reinforcing sheet 322 facing away from the valve sheet 321; the edges of the gaskets 33 are provided with round corners, and the round corners are positioned on one side close to the reinforcing sheets 322; the radius of the round angle is set to be 0.5mm-1mm. The gasket 33 is disposed between the screw and the reinforcing piece 322, and functions to assist the screw in fixing the valve plate 321 and the reinforcing piece 322 to the valve plate 31, thereby preventing the screw from damaging the reinforcing piece 322 and the valve plate 321. Specifically, the spacer 33 may be made of 304 stainless steel, and may have a thickness of 0.8mm to 1mm, a projected shape of square, and a single-side width of the spacer may be identical to a width of the short side of the reinforcing sheet 322. The edge of the gasket 33 facing the reinforcing sheet 322 can be rounded, and the radius of the rounded corner is set to be 0.5mm-1mm; this reduces the obstruction to the opening of the valve plate 321 and the optimum value of the corner radius corresponds to the thickness of the gasket 33. The threaded surface may be coated with a screw tightening glue to prevent loosening of the screw when the screw is tightened on the valve plate 31.

In some embodiments, valve plate 31 is provided with a first boss 313, first boss 313 extending along a side facing away from the cylinder block; the second air outlet 312 penetrates through the first boss 313, a transition hole 314 is formed in the first boss 313, and the axis of the second air outlet 312 is parallel to the axis of the transition hole 314; a second groove 315 is formed in the plane of one side, away from the cylinder body, of the first boss 313, the second groove 315 is formed along the circumferential direction of the first boss 313, and the second air outlet 312 and the transition hole 314 are both located in the range of the second groove 315; a second sealing ring is arranged in the second groove 315. The oil gas recovery pump provided by the embodiment of the invention can comprise the gland, and when the gland abuts against the second sealing ring, sealing connection is formed so as to prevent oil gas discharged from the cylinder body from escaping out and mixing with oil gas before entering the cylinder body, so that the running power of the oil gas recovery pump is consumed.

In some embodiments, the second air outlet 312 includes a first sub-outlet and a second sub-outlet coaxially communicating with the first sub-outlet, the first sub-outlet being disposed adjacent to the cylinder, and the first sub-outlet having a larger area than the second sub-outlet; the area of the second sub-outlet is larger than the second inlet 311. The expansion of the first sub-outlet can reduce the air outlet resistance, the area of the second sub-outlet is smaller than that of the first sub-outlet, the valve plate 321 of the second one-way valve is facilitated to be manufactured, and the area of the second sub-outlet is larger than that of the second air inlet 311, so that the running power of the oil gas recovery pump is reduced. Wherein the second inlet 311 is formed as a circular hole, and the second sub-outlet is enlarged as an ellipse.

In some embodiments, the valve plate 31 is provided with a pressure relief hole 316, the axis of the pressure relief hole 316 is perpendicular to the axis of the transition hole 314, and the pressure relief hole 316 is communicated with the transition hole 314; a first air outlet hole 317 is arranged in the transition hole 314, the first air outlet hole 317 penetrates through the first boss 313, and the first air outlet hole 317 is axially communicated with the transition hole 314; the first air outlet 317 is used to communicate with the air outlet channel on the housing; the valve plate 31 is provided with a second mounting hole 318, the second mounting hole 318 is axially communicated with the pressure relief hole 316, and the pressure relief valve 34 is arranged in the second mounting hole 318 so as to discharge part of oil gas through the pressure relief hole 316 when the oil gas discharged through the second air outlet 312 and the one-way valve 32 exceeds the preset pressure. The pressing cover is provided with a concave space corresponding to the first boss 313, so that the oil gas discharged from the cylinder body can be slowly released, and enters the air outlet channel on the shell through the transition hole 314; when the oil gas discharged from the cylinder exceeds the preset pressure, the pressure relief valve 34 is opened, and a part of the oil gas enters the pressure relief hole 316 and is discharged through the pressure relief valve 34 so as to achieve pressure release; the transition hole 314 thus corresponds to a three-way connection, which makes the overall structure compact by means of a smart design. Since the valve plate 31 is disposed in the first cavity 151 and the first cavity 151 is in communication with the intake passage 13, the oil gas discharged from the pressure release valve 34 directly enters the first cavity 151 and is circulated again to be recovered into the oil gas recovery pipe.

In some embodiments, the relief valve 34 includes: the pressure regulating nut 341, the spring 342 and the steel ball 343, wherein two ends of the spring 342 are respectively contacted with the pressure regulating nut 341 and the steel ball 343; a taper hole is arranged between the second mounting hole 318 and the pressure relief hole 316, the small end of the taper hole is communicated with the pressure relief hole 316, and the large end of the taper hole is communicated with the second mounting hole 318; the steel ball 343 is embedded in the taper hole; the second mounting hole 318 deviates from the one end of pressure release hole 316 and is equipped with the internal thread hole, and pressure regulating nut 341 is equipped with the external screw thread, external screw thread and internal thread hole looks adaptation. Specifically, the steel ball 343 is made of GCr15, and the surface hardness is required to be greater than HRC50; the steel ball 343 is embedded in the taper hole, the steel ball 343 is matched with the inclined plane of the taper hole, when the pressure regulating nut 341 is screwed in, the end face of the pressure regulating nut 341 abuts against the spring 342, the spring 342 pushes the steel ball 343 to be embedded in the taper hole, the steel ball 343 is matched with the inclined plane of the taper hole, and the steel ball 343 blocks the pressure relief hole 316; when the oil gas discharged from the cylinder exceeds the preset pressure, the oil gas pressure pushes the steel ball 343, the compression spring 342, the steel ball 343 is separated from the pressure release hole 316, and a part of the oil gas enters the pressure release hole 316 and is discharged through the second mounting hole 318 and the through hole of the pressure regulating nut 341, so as to release the oil gas pressure. By adjusting the position of the pressure adjusting nut 341, the highest operating pressure of the oil and gas recovery pump can be adjusted. The tapered hole is beneficial to guiding in the process that the steel ball 343 closes the pressure release hole 316.

In some embodiments, as shown in fig. 12-13, the piston device 20 may specifically include: a cylinder 21 and a piston assembly 22. The cylinder 21 is formed in a hollow cylindrical shape; part of the piston assembly 22 is located within the cylinder 21, the piston assembly 22 being arranged to move in the axial direction of the cylinder 21; the piston assembly 22 includes a piston ring 225, the piston ring 225 has a trumpet-shaped side wall, the piston ring 225 is slidably connected with the inner wall of the cylinder 21, and at least a portion of the side wall of the piston ring 225 at the large end is attached to the inner wall of the cylinder 21 to block oil and gas from one side of the piston assembly 22. The piston ring 225 can be made of a material with a certain elasticity, when the side wall of the piston ring 225 is in a horn shape, the piston ring 225 slides along the inner wall of the cylinder body 21, and the side wall at the large end of the piston ring 225 is attached to the inner wall of the cylinder body 21 and can be slightly contracted and deformed inwards when being extruded, so that the friction resistance of the piston ring 225 and the cylinder body 21 and the mutual abrasion brought by the friction resistance are reduced, the abrasion of the piston ring 225 can be delayed, the cylinder body 21 is not easy to be rubbed and leaked, the service life of the piston device 20 can be prolonged, the vacuum degree in the cylinder can be effectively kept, and the air return capability of the oil gas recovery pump is improved.

In some embodiments, the base material of the cylinder 21 may be made of aluminum alloy or stainless steel, specifically, may be made of aluminum alloy brand 6061, and may be aluminum alloy 7075 for application scenarios with severe use environments. For example, when an aluminum alloy is selected as the base material, the surface thereof may be plated with a NiP coating layer with a surface roughness ra0.4; when the base material of the cylinder body 21 is made of stainless steel, the preferable mark is 0Cr17Ni4Cu4Nb, the surface can be free from being coated, the surface hardness of the inner wall can reach more than HRC45 through heat treatment, and the surface roughness Ra0.4 is ensured; this can improve the wear resistance of the cylinder 21.

In some embodiments, the piston assembly 22 further comprises: a pressure plate 221 and a connecting rod. The connecting rod comprises a shaft sleeve 224 and a supporting body 223 connected with the shaft sleeve 224, the axis of the shaft sleeve 224 is perpendicular to the axis of the supporting body 223, and the axis of the supporting body 223 is parallel to the axis of the cylinder body 21; the shaft sleeve 224 is provided with a through mounting hole for mounting a transmission mechanism to drive the piston assembly 22 to move along the axial direction of the cylinder 21; the piston ring 225 is located between the pressing plate 221 and the connecting rod, and one end of the pressing plate 221 passes through the piston ring 225, and the pressing plate 221 is fixedly connected with the supporting body 223 through a threaded fastener, so that the relative position of the piston ring 225 is fixed between the pressing plate 221 and the connecting rod. The center of the pressing plate 221 may be provided with a counter bore, the supporting body 223 may be correspondingly provided with a threaded hole, a countersunk screw is inserted into the counter bore and screwed into the threaded hole, and the piston ring 225 may be clamped between the pressing plate 221 and the connecting rod; for example, the axis of the sleeve 224 is set to be horizontal, and the axis of the support body 223 is set to be vertical, so that the piston assembly 22 is driven to reciprocate vertically in the cylinder 21 by the transmission mechanism.

In some embodiments, the piston ring 225 includes a base plate connected to the small end of the sidewall, and the sidewall and base plate angle α is set to be greater than 90 degrees. The side walls are inclined outwards relative to the bottom plate, so that parts of the side walls are in contact with the inner wall of the cylinder body 21, friction resistance is reduced, and sealing between the side walls and the inner wall of the cylinder body 21 is well achieved.

In an exemplary embodiment, the angle α between the sidewall and the floor is set to 110-120 degrees. For example, the angle α between the side wall and the bottom plate is set to 112-115 degrees, so that the friction resistance is reduced and the side wall and the inner wall of the cylinder 21 can be better sealed.

In some embodiments, the thickness d of the sidewall is set to 0.5-1mm. Preferably, the thickness d of the side wall is set to 0.6mm, and when the thickness d of the side wall is designed to be too thick or too thin, the ideal state of slightly shrinking and deforming inward generated when the side wall is pressed against the inner wall of the cylinder 21 is not realized.

In some embodiments, piston ring 225 comprises a layer of a hybrid material with polytetrafluoroethylene matrix added with graphite. For example, the height of the piston ring may be set to 3.5mm. Specifically, the piston ring material can be PTFE added graphite, and the addition amount of the graphite can be adjusted within the range of 15% -25%; preferably, the amount of graphite added is 17%. Therefore, the piston ring has the characteristics of self lubrication, wear resistance, good sealing performance and the like, the friction force in the running process can be reduced, meanwhile, the PTFE matrix has certain capacity of containing granular foreign matters invaded in the pump, and hard foreign matters can be embedded into PTFE to become a part of the piston ring.

In some embodiments, the bottom plate is provided with a first hole 23 therethrough, and the inner diameter of the side wall is larger than the first hole; the end of the support 223 away from the shaft sleeve 224 is provided with a second hole 24; the pressing plate 221 is provided with a boss extending along the axial direction of the pressing plate 221; wherein, clamp plate 221 locates in the lateral wall, and the boss passes first hole 23 and imbeds in the second hole 24. The pressing plate 221 is sunk into the side wall, so that the height of the piston assembly can be reduced, and the working stroke of the piston assembly can be effectively increased under the condition that the height of the cylinder body 21 is unchanged; the boss passes through the first hole 23 and is embedded into the second hole 24, so that the positioning of the pressing plate 221 on the supporting body 223 can be realized, the installation is convenient, and the clamping of the piston ring 225 is also facilitated.

In some embodiments, support 223 is provided with a recess, which is located on the bottom surface of the second hole; the pressing plate 221 is provided with a bump, the bump 25 is located near the top surface of the bump, and the bump 25 is embedded in the groove. The protrusion 25 is embedded into the groove, so that the positioning of the pressing plate 221 on the supporting body 223 can be realized, the installation is convenient, and the piston device can be prevented from rotating the piston ring 225 in the working process.

In some embodiments, the inner wall of the cylinder 21 is provided with a coating having a thickness of 0.005mm-0.012mm. By providing a plating layer on the inner wall of the cylinder 21, wear resistance can be improved, thereby prolonging the service life of the cylinder 21.

In some embodiments, as shown in fig. 1, 2, and 14-16, the transmission mechanism 40 may specifically include: the crank shaft assembly, the transmission shaft 44, the first screw 45, the second screw 46 and the like, wherein a through internal threaded hole is formed in the transmission shaft 44, and the first screw 45 and the second screw 46 can be screwed into the internal threaded hole from two ends of the transmission shaft 44 respectively; the crank shaft assembly may be fixed to one end of the drive shaft 44 by a first screw 45 and the coupling 60 may be fixed to the other end of the drive shaft 44 by a second screw 46. The main bearing may be sleeved on the transmission shaft 44, and may be installed in an installation hole on the housing 10, and the main bearing may be located on a side of the housing 10 near the motor 70, where the transmission shaft 44 may be installed on the housing 10 through the main bearing, a stopper, and the like, and may implement rotational connection between the transmission shaft 44 and an inner ring of the main bearing. Therefore, the whole crank shaft assembly is supported by the main bearing and is in a cantilever structure, and the rotation axes of the crank shaft assembly and the transmission shaft 44 are positioned on the same axis, so that the design of each part is simplified, and the weight of the pump head is reduced.

In some embodiments, the crankshaft assembly may include a crankshaft 41, a crank 42, and a counterweight 43. The crankshaft 41 includes a cylindrical positioning portion 411 provided at the end and a cylindrical long shaft section 412 extending concentrically and convexly in the axial direction of the positioning portion 411, the diameter of the positioning portion 411 being larger than that of the long shaft section 412, both forming a stepped shaft shape; a tangential plane 413 is provided on the circumferential outer periphery of the long shaft section 412 in the axial direction thereof, and the tangential plane 413 and the axis of the positioning portion 411 are parallel to each other; a crank 42 including a cylindrical connecting portion 421 and a cylindrical shaft shoulder 422 connected to one side of the connecting portion 421 in the axial direction; the shaft shoulder 422 has a diameter larger than that of the connection portion 421, and forms a stepped shaft shape with the connection portion 421; the crank 42 is provided with a third mounting hole 423 in a penetrating manner along the axial direction, the third mounting hole 423 is eccentrically arranged, and one side, far away from the axis of the crank 42, of the third mounting hole 423 is a flat surface, and the flat surface is matched with the tangential plane 413 so as to realize the matched connection of the crank 42 and the crank shaft 41. The balancing weight 43 is provided with a fourth mounting hole 431, one side of the fourth mounting hole 431 is a flat surface, and the flat surface is matched with the tangential plane 413 so as to realize the matching connection of the balancing weight 43 and the crankshaft 41; the fourth mounting hole 431 is eccentrically disposed, and a flat surface of the fourth mounting hole 431 is disposed close to and toward the center of the weight 43. The crank 42 and the weight 43 are sleeved on the long shaft section 412 of the crank shaft 41, and the weight 43 is close to the positioning part 411, i.e. the weight 43 is located between the crank 42 and the positioning part 411. The connecting portion 421 of the crank 42 is sleeved with a piston bearing, the piston bearing is installed in the installation hole of the piston assembly 22, the piston assembly 22 is installed on the crank through the piston bearing, and the crank 42 and the inner ring of the piston bearing can be connected in a rotating mode. The pump head in the embodiment of the invention adopts a double-piston device to share the vacuumizing process, and the two cylinders 21 are symmetrically arranged by the rotation axis of the transmission mechanism 40, so that the two cranks 42 are sequentially positioned between the balancing weight 43 and the transmission shaft 44. The design makes the structure of each part of the crank shaft assembly simple, simplifies the whole processing technology and production cost of the crank shaft assembly, and the design of the tangential plane 413 of the crank shaft 41 can transmit torque to the crank 42, the balancing weight 43 and other parts under the condition of omitting the spline, thereby further simplifying the whole structure of the crank shaft assembly.

In some embodiments, to better fix and transfer torque to the crankshaft assembly, a fifth mounting hole may be provided at an end of the drive shaft 44 facing away from the motor 70, and a flat surface may be provided in the fifth mounting hole, and similarly, the flat surface is adapted to the tangential plane 413, so as to realize a mating connection between the drive shaft 44 and the crankshaft 41, so as to transfer torque; the long shaft section 412 of the crank shaft 41 is sleeved with the balancing weight 43 and the two cranks 42 in sequence, one end of the long shaft section 412 is inserted into the fifth mounting hole of the transmission shaft 44, and the first screw 45 penetrates through the crank shaft 41 and is screwed into the internal threaded hole of the transmission shaft 44 so as to realize torque transmission to the crank shaft assembly.

In some embodiments, the eccentricity of the third mounting hole 423 is set to be adjustable, and the eccentricity of the third mounting hole 423 is the distance between the third mounting hole 423 and the axis of the crank 42; in practical application, the eccentricity can be adaptively adjusted according to different parameter requirements of the oil gas recovery pump so as to meet the use requirements of more users; illustratively, the eccentricity is adjusted between 3mm and 3.75mm, and when the power of the oil and gas recovery pump is large, a larger eccentricity such as 3.75mm can be selected; when the power of the oil and gas recovery pump is smaller, smaller eccentricity such as 3mm can be selected; preferably, the eccentricity is set to 3.5mm.

In some embodiments, the hollow structure is disposed around the third mounting hole 423, so that the hollow structure can be in any shape and any position on the premise of ensuring the strength of the crank 42 and ensuring normal operation, and the purpose of the hollow structure is to save materials and reduce the weight of the crank 42; illustratively, the hollowed-out structure includes a through weight-reducing hole 424 and two through grooves, wherein the through grooves include a first through groove 425a and a second through groove 425b, which are respectively ivory-shaped; the center of the weight-reducing hole 424 is on the central symmetry line of the third mounting hole 423, and the through groove one 425a and the through groove two 425b are symmetrically distributed at two ends of the central symmetry line of the third mounting hole 423.

In some embodiments, the weight 43 may be any shape, such as a cylinder, a disc, a semicircle, etc., according to the needs of the practical application; the balancing weight 43 is in a cylindrical shape, and a weight adjusting hole 432 can be formed on the balancing weight 43 according to requirements, and the weight adjusting hole 432 can be arranged at any position, and is preferably arranged on two sides of the axis of the balancing weight 43 respectively with the fourth mounting hole 431; the balancing weight 43 designed in this way is arranged on the crankshaft 41, so that the rotation of the crankshaft assembly is more stable, the vibration generated in the operation process of the oil gas recovery pump is reduced, and the performance and the service life of the oil gas recovery pump are effectively improved.

The operating principle of the transmission mechanism 40 is as follows: the motor 70 drives the transmission shaft 44 to rotate through the connecting shaft device 60, and transmits torque to the crank 42 through the crank shaft 41 to drive the two piston assemblies 22 to axially move along the cylinder body; only one cutting plane 413 is arranged on the long shaft section 412 of the crank shaft 41, the cutting plane 413 faces the cylinder body 21 during assembly, two cranks 42 are sequentially sleeved on the balancing weight 43 and the transmission shaft 44, a piston bearing is sleeved on the connecting part 421 of the cranks 42, and then the assembled piston assembly 22 is sleeved on the piston bearing, because the eccentric distance is arranged on the third mounting hole 423 on the cranks 42, one of the two piston assemblies 22 is in a vacuumizing state, and the other is in an exhausting state, so that the transmission mechanism 40 can generate two vacuumizing actions every time when rotating for one circle.

A second aspect of the present invention provides an oil and gas recovery pump, as shown in fig. 21 and 22, comprising: pump head, coupling 60 and motor 70. A coupling 60 having one end connected and fixed to the transmission mechanism; the motor 70 comprises a connecting end cover 50, wherein the connecting end cover 50 is fixedly connected with the shell 10; the output shaft of the motor 70 is fixedly connected with the other end of the coupling 60. A fan may be disposed between the pump head and the motor 70 to perform a heat dissipation function, or a fan may not be installed. As shown in fig. 17-19, the connecting end cover 50 and the shell 10 can be directly connected and fixed; the connecting end cover 50 may be provided with a third hole 543 and a fourth hole 544 which are circumferentially spaced apart, and the third hole 543 may be used for connecting and fixing the connecting end cover 50 and the housing 10 by a threaded fastener; the motor 70 may further include a housing 71, on which a protrusion 72 may be disposed, and a fourth hole 544 may be used to connect and fix the connection end cap 50 to the protrusion 72 by a threaded fastener; third hole 543 and fourth hole 544 stagger each other and set up, and third hole 543 and fourth hole 544 all can be established to follow circumference inhomogeneous interval distribution, can set up the arc opening between the third hole 543, also can set up the arc opening 55 between the fourth hole 544, and such structure compares with traditional motor flange only on circumference evenly distributed trompil's structure, can alleviate the weight of connecting end cover 50, and then reduce the size of oil gas recovery pump's motor 70 and pump head for oil gas recovery pump holistic size reduces, whole outward appearance is more pleasing to the eye, can guarantee oil gas recovery pump steady operation simultaneously.

In an exemplary embodiment, the connection end cap 50 may include an annular connection body 51, and a motor connector 52 and a pump head connector 53 respectively protruding toward opposite sides along the connection body 51, the outer circumferential surface of the connection body 51 is convexly provided with a plurality of positioning connection portions 54, the positioning connection portions 54 may be arranged to be unevenly distributed at intervals along the circumferential direction, and the positioning connection portions 54 are provided with third holes 543 and fourth holes 544; since the plurality of positioning connection portions 54 are unevenly distributed on the outer circumferential surface of the connection body 51, and the arc-shaped slits 55 are formed between the adjacent two positioning connection portions 54, the arc-shaped slits 55 are not only used for preventing assembly interference, but also can reduce the weight of the connection end cap 50. The motor connector 52 is inserted into the housing 71 to perform a positioning function, thereby improving the overall stability of the motor. Similarly, the pump head connector 53 is inserted into the housing 10.

In some embodiments, the positioning connection portion 54 includes a first lug 541 and a second lug 542 connected to one side of the first lug 541, where the first lug 541 may be triangular, the second lug 542 may be square, and of course, both the first lug 541 and the second lug 542 may be trapezoidal, semicircular, or fan-shaped, and the like, which are not limited herein. The first lug 541 may have a third aperture 543 therein, and the second lug 542 may have a fourth aperture 544 therein.

In some embodiments, the thickness of the second lug 542 is 4.5mm-5.5mm, preferably 5mm, the thickness of the first lug 541 is 7.5mm-8.5mm, preferably 8mm, and the difference in thickness between the first lug 541 and the second lug 542 is 2mm-4mm, preferably 3mm. A portion of the first lug 541 thicker than the second lug 542 protrudes toward the motor connector 52 side.

In some embodiments, the number of the positioning connection portions 54 may be odd or even, and may be set according to needs in the practical application process, for example, two, four, six, or three, five, seven, etc.; and the positioning connections 54 are unevenly distributed.

In some embodiments, the positioning connection portions 54 are provided in four numbers, and the circumferentially distributed positions of the third holes 543 and the fourth holes 544 are symmetrically disposed with respect to the X axis, or symmetrically disposed with respect to the Y axis, or symmetrically disposed with respect to both the X axis and the Y axis.

In the exemplary embodiment, as shown in fig. 19, four positioning connection portions 54 are symmetrically disposed with respect to both the X-axis and the Y-axis; the included angle between the line between the center of the third hole 543 and the center of the connecting body 51 and the X axis is alpha; the included angle between the line between the center of the fourth hole 544 and the center of the connecting body 51 and the Y axis is β; wherein α is 40 ° -50 °, preferably 45 °; beta is 20 deg. -30 deg., preferably 25 deg..

In some embodiments, the motor 70 further includes an output shaft 73, one end of the output shaft 73 passes through the connection end cap 50 and exposes the connection end cap 50, and the output shaft 73 is mounted on the connection end cap 50 through a bearing support, the other end of the output shaft 73 is mounted on the housing 71 through a bearing support, and a motor body is disposed between the two bearings, where the motor body may include a stator, a rotor, and the like. A gap is provided between the connection end cap 50 and the motor body to perform insulation and interference prevention functions. An explosion-proof joint can be arranged on the shell 71, a through hole is arranged on the explosion-proof joint, the through hole is right opposite to the gap, so that a motor cable can be conveniently led into the shell 71 through the through hole, and the space of the motor cable is reserved at the gap. When the connecting end cover 50 is detached, the motor cable can be connected with the wiring terminal on the control board of the motor main body, and the daily maintenance of the motor main body can be realized, so that the whole weight of the motor 70 is reduced through the design of the connecting end cover 50, and the motor is convenient to detach and easy to maintain. The motor cable generally comprises a power line and a control line, wherein the outer layers of the power line and the control line can sequentially wrap the insulating rubber layer and the shielding layer, so that signal interference can not be generated even if the motor cable passes through one through hole. After the power line and the control line are combined into a whole, the motor cable can be protected and output to the power end or the control cabinet only by one explosion-proof hose, so that the installation is simpler and more convenient, the explosion-proof material is reduced, and the safety and the stability of the motor operation are effectively ensured.

In some embodiments, as shown in fig. 20 and 21, the coupling device 60 may include a first coupling 61, a second coupling 62, and a flexible member between the first coupling 61 and the second coupling 62. The flexible member may be, for example, a rubber pad 63; one end of the first connector 61 is a motor connecting sleeve 611 which is connected with an output shaft 73 of a motor, the other end is a first flange 612, and a plurality of protruding first supporting claws 613 are arranged on the first flange 612; one end of the second coupling 62 is a pump head connecting sleeve 621 which is connected with a transmission shaft 44 of the pump head, the other end is a second flange 622, and a plurality of protruding second supporting claws 623 are arranged on the second flange 622; the rubber packing 63 is disposed between the first flange 612 and the second flange 622, and a plurality of through holes are opened on the rubber packing 63, the positions of the through holes respectively correspond to the positions of the first claws 613 and the positions of the second claws 623; the first and second claws 613 and 623 are inserted into through holes at corresponding positions on the rubber pad 63 from both sides of the rubber pad 63, respectively, and the first and second flanges 612 and 622 are tightly fitted with the rubber pad 63.

The coupling device in the embodiment of the invention is split, the two couplings are respectively connected with the output shaft main shaft of the motor and the transmission shaft of the pump head, and the connection between the two split couplings is completed in a mode that each claw is embedded into a rubber gasket by arranging special-shaped claws on the opposite end surfaces of the two couplings. The flexible piece has certain elastic deformation capacity for the rubber gasket, and compared with metal hard connection, the damage possibility of mechanical parts can be reduced by connecting the two shaft connectors through the rubber gasket, and meanwhile, the transmission of motor torque can be ensured. The connection mode in the embodiment of the invention can facilitate the disassembly of the motor and the pump head, the motor can be kept as the same, the cable connected to the motor can not change, and only the two couplers are required to be separated.

Optionally, according to the embodiment of the present invention, the rubber gasket 63 serves to buffer the pretightening force between the two flange surfaces, and the thickness of the rubber gasket 63 can be adjusted according to actual needs, when the lengths of the first leg 613 and the second leg 623 are both greater than the thickness of the rubber gasket 63, the second leg 623 extends out of the through hole of the rubber gasket 63 to the first flange 612, and similarly, the first leg 613 also extends out of the through hole of the rubber gasket 63 to the second flange 622. At this time, if the two flange faces are not provided with accommodating spaces at the positions where the opposite side support claws extend, the two flange faces can be respectively supported by the opposite side support claws, so that the two flange faces cannot be tightly attached, and the connection of the two shaft connectors is unstable due to the middle gap, so that the shaft connecting effect of the shaft connecting device cannot be achieved. Therefore, the first flange 612 is provided with a plurality of first receiving spaces at corresponding positions of the second claws 623 to receive the second claws 623; the second flange 622 is provided with a plurality of second receiving spaces at corresponding positions of the first jaw 613 to receive the first jaw 613. The claws extending to the opposite flange can extend into the well arranged containing space on the flange, so that the two flanges are tightly attached to each other, and the first coupling 61 and the second coupling 62 realize coaxial transmission.

Alternatively, according to an embodiment of the present invention, the number of the first claws 613 on the first flange 612 is three, and the first claws 613 are uniformly distributed at circumferential intervals on the first flange 612, that is, the central angle between two adjacent first claws is 120 °. Similarly, the number of the second claws 623 is three, and the three second claws 623 are uniformly distributed on the second flange 622 at circumferential intervals, namely, the central angle between two adjacent second claws is 120 degrees; and the distribution circle diameters of the first and second claws 613 and 623 may be set to be the same and concentrically arranged. When the first and second claws 613 and 623 are inserted into the through holes in the corresponding positions of the rubber pad 63, the first and second claws 613 and 623 may be positioned between two adjacent second claws 623, i.e., the second claws 623 are also positioned between two adjacent first claws 613, so that the circumferential dimension of the coupling may be reduced, the structure is compact, and the distribution of the first and second claws all forms a triangle, so that the torque transmission is more stable. Because the machine is affected by structural requirements, manufacturing and installation errors, changes in operating temperature, deformation after bearing, and other factors, the two shafts connected by the coupler often cannot be centered, and relative displacement exists in a certain range. If these displacements are not compensated, additional loads are generated on the coupling, shaft and bearings, even causing strong vibrations. So the distribution circle of the three first supporting claws 613 and the distribution circle of the three second supporting claws are concentric with the transmission shaft, the stability of coaxial transmission can be ensured, and the rubber gasket is a flexible piece, so that certain relative displacement can be compensated, and the stability of coaxial transmission can be realized.

Further, when the first claws 613 and the second claws 623 are distributed as described above, the corresponding first accommodating space and second accommodating space can be uniformly distributed on the respective flanges, so that the claws extending from the opposite flange can be securely accommodated. According to the embodiment of the invention, the plurality of first accommodating spaces are a plurality of arc-shaped openings formed from the edge of the first flange to the axis, and the plurality of second accommodating spaces are a plurality of arc-shaped openings formed from the edge of the second flange to the axis. The radian of the arc opening does not need to be clearly required, as long as the arc opening does not interfere and collide with the opposite extending supporting claws. And excess material on the first flange 612 and the second flange 622 can also be removed by the design of the arcuate openings to reduce the weight of the two couplings.

Optionally, according to the embodiment of the present invention, the chamfer is provided on the end of each first claw 613 and each second claw 623, so that the diameter of the end of each claw is smaller, and the claw can be conveniently inserted into the through hole of the rubber gasket 63, especially when the diameter of the through hole of the rubber gasket 63 is equal to or slightly smaller than the diameter of each claw, after the assembly is completed, the rubber gasket can form tight connection with each claw, so that two connectors are better protected, the service life of the connecting shaft device is prolonged, and the stability of coaxial transmission can be enhanced.

In some embodiments, the motor connecting sleeve 611 may be provided as a hollow sleeve, a positioning key groove may be provided on an inner wall of the sleeve, an adaptive positioning key is provided on the output shaft 73 of the motor, when the output shaft 73 of the motor is inserted into the motor connecting sleeve 611, torque is transmitted through key connection, and a screw is inserted into the motor connecting sleeve 611 from the first claw 613 side and screwed into a threaded hole of the output shaft 73, so as to realize connection and fastening of the first connector 61 and the output shaft 73, and prevent axial displacement between the first connector 61 and the output shaft 73. Similarly, the same embodiment may be used to connect and secure the pump head connection sleeve 621 to the drive shaft 44 of the pump head. The outer wall of the pump head connecting sleeve 621 can be provided with a protruding positioning key, the end part of the transmission shaft 44 is provided with a notch matched with the positioning key, when the pump head connecting sleeve 621 is inserted into the transmission shaft 44, the positioning key is clamped into the notch, and a screw is inserted into the pump head connecting sleeve 621 from the second support claw 623 side and screwed into a threaded hole of the transmission shaft 44, so that the second coupler 62 is connected and fastened with the transmission shaft 44, and the axial displacement between the second coupler 62 and the transmission shaft 44 can be prevented.

In the embodiment of the invention, the power consumption in the operation process of the oil gas recovery pump is reduced by adopting the ultrathin one-way valve plate, and the power of the matched motor can be reduced to about 80W; and the weight of the whole machine comprising the pump head and the motor can be reduced to about 3.5kg through a series of light-weight designs.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explanation of the principles of the present invention and are in no way limiting of the invention. Accordingly, any modification, equivalent replacement, improvement, etc. made without departing from the spirit and scope of the present invention should be included in the scope of the present invention. Furthermore, the appended claims are intended to cover all such changes and modifications that fall within the scope and boundary of the appended claims, or equivalents of such scope and boundary.

Claims

1. A pump head, comprising:

the shell is provided with a hollow accommodating cavity, a first air inlet and a first air outlet are arranged on the shell, and the first air inlet and the first air outlet are positioned in the same plane; an air inlet channel communicated with the first air inlet and an air outlet channel communicated with the first air outlet are arranged in the shell, the axes of the air inlet channel and the air outlet channel are approximately parallel, the axes of the first air inlet and the first air outlet are approximately parallel, and the axes of the air inlet channel and the first air inlet are approximately vertical;

the piston devices are arranged in the accommodating cavity of the shell, and the number of the piston devices is two; the piston device comprises a piston assembly and a cylinder body, wherein part of the piston assembly is positioned in the cylinder body, and the piston assembly is arranged to move along the axial direction of the cylinder body;

The valve plate assembly comprises a valve plate, the valve plate is positioned on one side of the cylinder body, the valve plate is in sealing connection with one end face of the cylinder body, and a second air inlet and a second air outlet are formed in the valve plate;

the drive mechanism, it sets up in the hold intracavity of casing, drive mechanism includes: the crankshaft assembly and the transmission shaft are positioned on the same axis, the crankshaft assembly is positioned on one side of the transmission shaft, and the transmission shaft drives the crankshaft assembly to rotate; the piston assembly is sleeved on the crankshaft assembly, so that the transmission mechanism drives the piston assembly to move along the axial direction of the cylinder body in a direction approaching to or separating from the valve plate; the transmission mechanism is positioned between the two cylinders, the two cylinders are symmetrically arranged with the rotation axis of the transmission mechanism, and the axes of the two cylinders are the same and are approximately perpendicular to the rotation axis of the transmission mechanism; the rotation axis of the transmission mechanism is approximately parallel to the axis of the first air inlet;

the oil gas sequentially passes through the first air inlet and the air inlet channel, is respectively led into the cylinder body through the second air inlet in two paths, respectively enters the air outlet channel through the second air outlet, and is converged in the air outlet channel to enter the first air outlet.

2. The pump head of claim 1, wherein the valve plate assembly further comprises:

the check valve is arranged on one side of the valve plate, and is arranged at the downstream of the direction of the oil gas flowing through the second air inlet or the second air outlet; the one-way valve comprises a valve plate and a reinforcing plate, the valve plate covers the second air inlet or the second air outlet, and the valve plate is positioned between the reinforcing plate and the valve plate; the thickness of the reinforcing sheet is set to be adjustable so as to adjust the closing or opening pressure of the one-way valve.

3. The pump head of claim 1 wherein the first air inlet and the first air outlet are located on either side of the drive mechanism, respectively, and the first air inlet is higher than the first air outlet;

the planes of the first air inlet and the first air outlet are opposite to the motor mounting surface.

4. The pump head of claim 2 wherein the pump head is configured to,

the two ends of the shell are respectively provided with a first protruding mounting flange, the end face of the first mounting flange and the end face of the shell are both positioned on a first mounting face, and the first mounting face is parallel to the rotation axis of the transmission mechanism;

The first mounting surface is provided with first threaded holes which are circumferentially and alternately distributed along the accommodating cavity of the shell; the valve plate is provided with a first through hole which is matched with the first threaded hole so as to mount the valve plate on the shell; the valve plate is provided with a mounting groove, and one end of the cylinder body is embedded into the mounting groove.

5. The pump head of claim 4, further comprising:

the gland is fixedly connected with the first mounting flange; one side of the gland is provided with a concave first cavity, and the other opposite side of the gland protrudes; the valve plate is positioned in the first cavity, and the first cavity is communicated with the air inlet channel;

the first mounting flange is provided with second threaded holes which are distributed at intervals along the circumferential direction of the first mounting flange; the gland is provided with a second through hole which is matched with the second threaded hole so as to mount the gland on the first mounting flange;

the circumferential distribution size of the second threaded holes is larger than that of the first threaded holes;

the first mounting surface is provided with a first groove, the first groove surrounds the inner cavity of the shell, and the first groove is positioned between the first threaded hole and the second threaded hole; the first groove is internally provided with a first sealing ring, and the end face of the gland contacts with the first sealing ring so as to prevent oil gas in the accommodating cavity of the shell from escaping to the outside atmosphere.

6. The pump head of claim 5 wherein said valve plate has a first boss thereon, said first boss extending along a side facing away from said cylinder; the second air outlet penetrates through the first boss, a transition hole is formed in the first boss, and the axis of the second air outlet is parallel to the axis of the transition hole;

a second groove is formed in a plane of one side, away from the cylinder body, of the first boss, the second groove is formed along the circumferential direction of the first boss, and the second air outlet and the transition hole are both located in the range of the second groove; a second sealing ring is arranged in the second groove;

a second boss is arranged in the first cavity, the shape of the second boss is identical to that of the first boss, a sunken second cavity is arranged in the second boss, the second cavity is communicated with the transition hole, and a one-way valve at the second air outlet is positioned in the second cavity; the second boss contacts the second sealing ring to prevent oil gas in the first cavity and the second cavity from flowing and channeling each other.

7. The pump head of claim 6 wherein the second air outlet comprises a first sub-outlet and a second sub-outlet in coaxial communication with the first sub-outlet, the first sub-outlet being positioned adjacent the cylinder and the first sub-outlet having a larger area than the second sub-outlet; the area of the second sub-outlet is larger than that of the second air inlet.

8. The pump head of claim 6, wherein the valve plate is provided with a pressure relief hole, the axis of the pressure relief hole is perpendicular to the axis of the transition hole, and the pressure relief hole is communicated with the transition hole;

a first air outlet hole is formed in the transition hole, penetrates through the first boss, and is axially communicated with the transition hole; the first air outlet hole is used for communicating with an air outlet channel on the shell;

the valve plate is provided with a second mounting hole which is axially communicated with the pressure relief hole, and a pressure relief valve is arranged in the second mounting hole so as to discharge part of oil gas through the pressure relief hole when the oil gas discharged through the second air outlet and the one-way valve exceeds the preset pressure.

9. The pump head of any one of claims 5-8 wherein a plurality of first mounting posts are provided on an outer side of the housing in spaced apart relation, the first mounting posts being adapted to mount the pump head so that the relative positions of the pump heads are fixed; or,

the outer side face of the gland is provided with a plurality of second mounting columns which are distributed at intervals, and the second mounting columns are used for mounting the pump head so that the relative position of the pump head is fixed.

10. An oil and gas recovery pump, comprising:

a pump head as claimed in any one of claims 1 to 9;

one end of the connecting shaft device is fixedly connected with the transmission mechanism;

the motor comprises a connecting end cover, wherein the connecting end cover is fixedly connected with the shell; and an output shaft of the motor is fixedly connected with the other end of the connecting shaft device.