CN113432027A

CN113432027A - Grease pump head and grease pump

Info

Publication number: CN113432027A
Application number: CN202110845676.0A
Authority: CN
Inventors: 梅立文; 李�根; 邓帅奇; 焦立军; 姜友爱
Original assignee: Zhengzhou Zhongcheng Lubrication Technology Co ltd
Current assignee: Zhengzhou Zhongcheng Lubrication Technology Co ltd
Priority date: 2021-07-26
Filing date: 2021-07-26
Publication date: 2021-09-24
Anticipated expiration: 2041-07-26
Also published as: CN113432027B

Abstract

The invention relates to a grease pump head and a grease pump, the grease pump comprises the grease pump head and an oil tank, the grease pump head comprises a pump shell, an oiling piston and a driving shaft, the pump shell is provided with a pump shell inner cavity and an oiling channel used for injecting oil outwards, the driving shaft can drive the oiling piston to move and inject oil into the oiling channel when rotating forwards, an unloading piston assembly is also arranged in the pump shell, the unloading piston assembly comprises an unloading piston sleeve and an unloading piston matched with the unloading piston sleeve in a sliding way, the unloading piston has an unloading position and a working position in the reciprocating motion stroke, when the unloading piston is at the unloading position, the oiling channel discharges oil into the pump shell inner cavity, when the unloading piston is at the working position, the oiling channel stops discharging oil into the pump shell inner cavity, and the driving shaft can drive the unloading piston to move to the unloading position only when rotating backwards. The invention aims to provide a grease pump, which is used for solving the problems that the existing grease pump is high in cost and an electromagnetic valve for unloading is easy to damage.

Description

Grease pump head and grease pump

Technical Field

The invention relates to a grease pump head and a grease pump.

Background

The existing vehicles and engineering mechanical equipment are all provided with a centralized lubricating system to supply lubricating oil to lubricating points of the equipment, and a grease pump is used as a core component of the centralized lubricating system to play an important role in the operation of the whole system. The grease pump includes oil tank and grease pump head, the grease pump head includes the pump case, the pump case has the pump case inner chamber and is used for the oiling passageway of outside oiling, be equipped with oiling piston assembly and drive shaft in the pump case, the rotation of drive shaft drives the oiling piston reciprocating motion of oiling piston assembly, the grease in the pump case inner chamber is absorb to the reciprocating motion of oiling piston assembly through the oiling, and carry the grease to the oiling passageway, the oiling passageway is external to have defeated oil pipe, the grease in the oiling passageway is carried to the lubricated position of equipment through defeated oil pipe, the oil tank of grease pump has the oil storage chamber, the grease in the oil storage chamber supplies oil to in the pump case inner chamber.

Because the amount of grease consumed in the lubricating process is relatively small, the grease pump generally adopts an intermittent injection oil supply mode, and the grease pump needs to unload high-pressure grease in an oil pipeline after primary oil injection is completed.

Disclosure of Invention

The invention aims to provide a grease pump, which is used for solving the problems that the existing grease pump is high in cost and an electromagnetic valve for unloading is easy to damage. The invention also provides a grease pump head.

The technical scheme of the grease pump head of the invention is as follows:

the grease pump head includes:

the pump shell is provided with a pump shell inner cavity and an oil injection channel for injecting oil outwards;

an oil injection piston;

the driving shaft can drive the oil injection piston to move to inject oil into the oil injection channel in forward rotation;

the unloading piston assembly comprises an unloading piston sleeve arranged in the inner cavity of the pump shell and an unloading piston in sliding fit with the unloading piston sleeve; the unloading piston sleeve is provided with an oil drainage port communicated with the oil filling channel and an oil outlet communicated with the inner cavity of the pump shell, the unloading piston has an unloading position and a working position in the reciprocating motion stroke, when the unloading piston is at the unloading position, the oil drainage port is communicated with the oil outlet so that the oil filling channel drains oil into the inner cavity of the pump shell, and when the unloading piston is at the working position, the oil drainage port is disconnected with the oil outlet so as to prevent the oil filling channel from draining oil into the inner cavity of the pump shell;

a one-way transmission structure is arranged between the driving shaft and the unloading piston and is used for enabling the driving shaft to drive the unloading piston to move to an unloading position only when the driving shaft rotates reversely;

the unloading piston is driven by the reverse driving shaft when moving from the unloading position to the working position, or the unloading piston assembly comprises a reset elastic part which provides acting force for the unloading piston, and the reset elastic part can enable the unloading piston to move from the unloading position to the working position when the driving shaft rotates reversely.

Has the advantages that: the oil injection pump has the advantages that the oil injection piston is driven to move to inject oil into the oil injection channel when the driving shaft rotates forwards, the driving shaft with the one-way transmission structure can only drive the unloading piston to move when the driving shaft rotates backwards, the unloading piston enables the oil injection channel to drain oil into the inner cavity of the pump case when being positioned at an unloading position, the oil injection channel is prevented from draining oil into the inner cavity of the pump case when being positioned at a working position, the high-pressure oil in the oil injection channel is drained into the inner cavity of the pump case by the aid of the oil pump head through the unloading piston assembly, additional external bypass pipes and electromagnetic valves are not needed, cost is reduced, and the problem that the electromagnetic valve existing in the existing oil pump is easy to damage is solved.

Furthermore, an unloading cam is arranged on the driving shaft, the one-way transmission structure is arranged between the unloading cam and the driving shaft, and the unloading piston is driven to move by the unloading cam when the driving shaft rotates reversely.

Has the advantages that: the unloading cam is adopted to drive the unloading piston to move, and the transmission structure is simple in structure and convenient to process and assemble.

Further, the one-way transmission structure is a one-way bearing.

Has the advantages that: the one-way transmission structure of the one-way bearing is simple in structure and convenient to install.

Furthermore, the unloading cam is in pushing fit with the unloading piston, and when the driving shaft rotates reversely, the unloading cam enables the unloading piston to move to an unloading position by pushing the unloading piston.

Has the advantages that: the unloading cam and the unloading piston top adopt the transmission mode of push fit, so that the unloading cam has a simpler structure and is convenient to machine and form.

Further, the return elastic element is an unloading piston return spring.

Has the advantages that: the spring has simple structure and is convenient to install.

Furthermore, the unloading piston return spring is sleeved on the unloading piston, one end of the unloading piston return spring is abutted against the unloading piston sleeve, and the other end of the unloading piston return spring is abutted against the end part of the unloading piston.

Has the advantages that: the structure is simple and convenient to install.

Furthermore, the unloading piston is provided with an oil drainage channel for communicating the oil drainage port with the oil outlet, when the unloading piston is at an unloading position, the oil drainage channel enables the oil drainage port to be communicated with the oil outlet, and when the unloading piston is at a working position, the oil drainage channel enables the oil drainage port to be disconnected with the oil outlet.

Has the advantages that: the oil drainage channel is arranged, so that when the oil drainage port is communicated with the oil outlet, the length of the unloading piston extending out of the unloading piston sleeve does not need to be too long, and the phenomenon that the whole grease pump head is too large due to too large distance between the unloading piston and the driving shaft is avoided.

Furthermore, the grease pump head also comprises a motor for driving the driving shaft to rotate positively and negatively and a controller for controlling the motor to rotate positively and negatively.

Has the advantages that: the controller for controlling the motor to rotate forward and backward is arranged to control the forward and backward rotation of the driving shaft more accurately and conveniently.

The unloading piston assembly further comprises a touch switch, a switch trigger is arranged on the unloading piston, the touch switch is used for being in contact with the switch trigger when the unloading piston moves to an unloading position and sending a trigger signal to the controller by being triggered by the switch trigger, so that the controller controls the motor to stop rotating, the switch trigger is axially and slidably arranged on the unloading piston, a touch spring used for applying elastic force towards the direction of the touch switch to the switch trigger is arranged on the unloading piston, and the touch spring is compressed when the switch trigger is in contact with the touch switch.

Has the advantages that: when the unloading piston moves to the unloading position, the touch switch is triggered and sends a signal to the controller, the motor and the driving shaft can automatically stop rotating at the moment, the opening and closing of the motor are not required to be controlled manually, the operation steps are simplified, and the touch switch is favorable for more accurately positioning the unloading position of the unloading piston. In addition, the arrangement that the switch trigger part is in sliding fit with the unloading piston enables the unloading piston to move to an unloading position, the switch trigger part can compress the touch spring to reduce acting force on the touch switch, and the touch switch cannot be damaged due to continuous pressing of the switch trigger part which moves through inertia.

The technical scheme of the grease pump is as follows:

the grease pump includes oil tank and grease pump head, and the oil tank is arranged in to the grease pump head fuel feeding, and the grease pump head includes:

an oil injection piston;

Further, the one-way transmission structure is a one-way bearing.

Further, the return elastic element is an unloading piston return spring.

Has the advantages that: the structure is simple and convenient to install.

Drawings

FIG. 1 is a front view of a grease pump embodiment 1 of the present invention;

FIG. 2 is a sectional view taken along line A of FIG. 1;

FIG. 3 is a sectional view taken along line B of FIG. 1;

FIG. 4 is a top view of a grease pump head;

FIG. 5 is a left side view of FIG. 4;

FIG. 6 is a block diagram of the pump housing;

FIG. 7 is a cross-sectional view taken along line C of FIG. 6;

FIG. 8 is a cross-sectional view of the oiling piston assembly;

FIG. 9 is a cross-sectional view of the unloader piston assembly.

In the figure: 1. an oil tank; 101. an oil storage chamber; 102. a grease bag; 103. a guide shaft; 2. a grease pump head; 3. a pump housing; 4. the inner cavity of the pump shell; 5. an oil injection channel; 6. an oiling piston assembly; 7. an unloading piston assembly; 8. a drive shaft; 9. an oil injection piston; 10. an unloading piston; 11. a protective housing; 12. a grease pump mounting bracket; 13. an oil injection cavity; 14. an oil drainage cavity; 15. an unloading cam assembly; 16. an oiling cam assembly; 17. a motor; 18. an oiling piston sleeve; 19. an unloading piston sleeve; 20. an oiling piston channel; 21. an oil filling piston sleeve oil inlet hole; 22. an oil outlet hole of the oiling piston sleeve; 23. an inner cavity of the oiling piston sleeve; 24. a one-way valve; 25. an oiling piston return spring; 26. an oil drainage port; 27. an oil outlet; 28. an inner cavity of the unloading piston sleeve; 29. an unloading piston cavity; 30. a touch switch; 301. a contact arm; 31. a potential contact ring; 32. an oil drainage channel; 33. an unloading piston oil inlet hole; 34. an unloading piston oil outlet; 35. a slide bar; 36. a spring seat; 37. a check valve return spring; 38. a plug; 39. a piston ring sleeve; 40. a touch position spring; 41. a stop seat; 42. an unloading piston return spring; 43. and (4) a valve.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The features and properties of the present invention are described in further detail below with reference to examples.

Specific example 1 of the grease pump of the present invention:

as shown in fig. 1 to 9, the grease pump includes an oil tank 1 and a grease pump head 2, the grease pump head 2 includes a pump case 3, the pump case 3 has a pump case inner cavity 4 and an oil injection passage 5 for injecting oil outwards, an oil injection piston assembly 6 is arranged in the pump case 3, an unloading piston assembly 7 and a drive shaft 8, the forward rotation of the drive shaft 8 can drive the oil injection piston 9 of the oil injection piston assembly 6 to reciprocate, the oil injection piston assembly 6 sucks the grease in the pump case inner cavity 4 through the reciprocating motion of the oil injection piston 9 and conveys the grease to the oil injection passage 5, the oil injection passage 5 is externally connected with an oil delivery pipe, and the grease in the oil injection passage 5 is conveyed to the lubrication point of the equipment through the oil delivery pipe. A one-way transmission structure is arranged between the driving shaft 8 and the unloading piston assembly 7, so that the driving shaft 8 can drive the unloading piston 10 of the unloading piston assembly 7 to move only when the driving shaft rotates reversely, and the unloading piston 10 enables high-pressure grease in the oil filling channel 5 to be discharged into the inner cavity 4 of the pump shell.

The oil tank 1 is a cubic shell, the oil tank 1 is provided with an oil storage cavity 101, the oil storage cavity 101 is provided with a grease bag 102, and the grease bag 102 is used for supplying oil to the inner cavity 4 of the pump shell. The guide shaft 103 is arranged in the middle of the grease pack 102, when the grease pack 102 is compressed to supply oil to the pump shell inner cavity 4, the grease pack 102 can be uniformly compressed along the axial direction of the guide shaft 103, and the problem of grease residue caused by nonuniform compression deformation of the grease pack 102 is avoided. The grease pump head 2 further comprises an external protective shell 11, the protective shell 11 plays a role in isolation protection for the grease pump head 2, the protective shell 11 is connected with the oil tank 1, and a grease pump mounting support 12 is arranged on the protective shell 11.

More specifically, as shown in fig. 4, 6, and 7, an oil filling cavity 13 and an oil draining cavity 14 are provided on the oil filling channel 5 of the pump housing 3, and when the grease pump fills oil to the outside, grease delivered by the oil filling piston assembly 6 firstly enters the oil filling cavity 13, then flows into the oil draining cavity 14 through the oil filling channel 5, and then flows into an external oil delivery pipe through the oil filling channel 5. After primary oil injection is completed, when the grease pump unloads high-pressure grease in the oil delivery pipe, the high-pressure grease in the oil delivery pipe flows into the oil drainage cavity 14 through the oil injection channel 5, and the unloading piston assembly 7 enables the grease in the oil drainage cavity 14 to be drained into the inner cavity 4 of the pump shell.

The grease pump head 2 further comprises an unloading cam assembly 15, a filling cam assembly 16, a motor 17 for driving the driving shaft 8 to rotate positively and negatively, and a controller for controlling the motor 17 to rotate positively and negatively. The unloading cam assembly 15 comprises a one-way transmission structure arranged on the driving shaft 8 and an unloading cam in transmission connection with the one-way transmission structure, in the embodiment, the one-way transmission structure is a one-way bearing, the one-way bearing is simple in structure and convenient to install, and the driving shaft 8 drives the unloading piston 10 to move only through the unloading cam when rotating reversely. The oiling cam assembly 16 comprises a transmission key arranged on the driving shaft 8 and an oiling cam in transmission connection with the transmission key, and the oiling piston 9 is driven to move by the oiling cam when the driving shaft 8 rotates forwards. The transmission structure adopting the cam to drive the unloading piston 10 and the oiling piston 9 to move has a simple structure and is convenient to process and assemble.

As shown in fig. 4, 6, 7, and 8, the oil injection piston assembly 6 includes an oil injection piston sleeve 18 disposed in the pump housing inner cavity 4 and an oil injection piston 9 slidably engaged with the oil injection piston sleeve 18, the channel for the oil injection piston 9 to slide in the oil injection piston sleeve 18 is an oil injection piston channel 20, the oil injection piston sleeve 18 is provided with an oil injection piston sleeve oil inlet 21 communicating the pump housing inner cavity 4 and the oil injection piston channel 20, the oil injection piston sleeve 18 is further provided with an oil injection piston sleeve oil outlet 22 for injecting oil into the oil injection cavity 13 and an oil injection piston sleeve inner cavity 23 for communicating the oil injection piston sleeve oil outlet 22 with the oil injection piston channel 20, in particular, a check valve 24 is disposed between the oil injection piston sleeve inner cavity 23 and the oil injection piston channel 20, the check valve 24 includes a valve 43, a sliding rod 35, and a spring seat 36, the valve 43 and the sliding rod 35 are integrally formed, the spring seat 36 is provided with a mating hole for the sliding rod 35 to pass through, the sliding rod 35 penetrates through the matching hole and is in sliding fit with the spring seat 36 along the axial direction of the sliding rod 35 so as to realize the reciprocating motion of the valve 43, the reciprocating motion of the valve 43 realizes the communication and disconnection between the cavity 23 in the oil injection piston sleeve and the oil injection piston channel 20, the sliding rod 35 is sleeved with a one-way valve return spring 37, and the one-way valve return spring 37 provides return elastic force for the valve 43. The spring seat 36 is provided with a grease passage for grease to pass through, so that the one side of the spring seat 36 facing the valve 43 is prevented from forming vacuum, and the normal operation of the check valve 24 is prevented from being influenced. More specifically, to prevent grease from escaping from the side of spring cup 36 facing away from valve 43, filler piston sleeve 18 is provided with a plug 38. Furthermore, the oiling piston assembly 6 comprises an oiling piston return spring 25 for providing return spring force to the oiling piston 9.

When the grease pump is filled with grease outwards, the motor 17 drives the driving shaft 8 to rotate forwards, the rotating driving shaft 8 drives the grease injection cam to rotate forwards through the transmission key, the grease injection piston 9 reciprocates under the pushing action of the grease injection cam and the action of the return elastic force of the grease injection piston return spring 25, when the grease injection piston 9 extends to the position where the grease injection piston sleeve oil inlet hole 21 and the grease injection piston channel 20 are in a communicated state, grease in the pump shell inner cavity 4 can enter the grease injection piston channel 20, when the grease injection piston 9 retracts, the grease entering the grease injection piston channel 20 can be compressed, the compressed grease applies pressure to the one-way valve 24 to drive the valve 43 to move backwards, at the moment, the grease injection piston sleeve inner cavity 23 is communicated with the grease injection piston channel 20, the grease can enter the grease injection piston sleeve inner cavity 23 and then flows out of the grease injection piston sleeve oil outlet hole 22 and enters the grease injection cavity 13, the grease entering the grease injection cavity 13 can flow into an externally-connected oil delivery pipe through the grease injection channel 5, finally flows to the lubrication point of the equipment through the oil pipeline.

As shown in fig. 4, 6, 7 and 9, the unloading piston assembly 7 includes an unloading piston sleeve 19 disposed in the pump case inner cavity 4 and an unloading piston 10 slidably fitted with the unloading piston sleeve 19, the unloading piston sleeve 19 is provided with an oil drain port 26 communicated with the oil drain cavity 14 and an oil outlet 27 communicated with the pump case inner cavity 4, the unloading piston 10 has an unloading position and a working position in a reciprocating stroke, when the unloading piston 10 is at the unloading position, the oil drain port 26 is communicated with the oil outlet 27, so that the oil filling channel 5 drains oil to the pump case inner cavity 4, and when the unloading piston 10 is at the working position, the oil drain port 26 is disconnected from the oil outlet 27 to prevent the oil draining channel 5 from draining oil to the pump case inner cavity 4. The unloading piston sleeve 19 is internally provided with an unloading piston sleeve inner cavity 28 communicated with the oil drainage port 26 and an unloading piston cavity 29 used for communicating the unloading piston sleeve inner cavity 28. The unloading piston assembly 7 further comprises a reset elastic member, the reset elastic member provides acting force for the unloading piston 10 to move from the unloading position to the working position, in the embodiment, the reset elastic member is an unloading piston return spring 42, one end of the unloading piston return spring 42 abuts against the unloading piston sleeve 19, and the other end abuts against the end part of the unloading piston 10 outside the unloading piston sleeve 19.

More specifically, the unloading piston 10 has an oil drainage channel 32 for communicating the oil drainage port 26 with the oil outlet 27, and the oil drainage channel 32 is provided with an unloading piston oil inlet hole 33 and an unloading piston oil outlet hole 34, when the unloading piston 10 is at the unloading position, the unloading piston oil inlet hole 33 is communicated with the unloading piston sleeve inner cavity 28, and the unloading piston oil outlet hole 34 is communicated with the oil outlet 27. The oil drainage channel 32 is arranged so that when the oil drainage port 26 is communicated with the oil outlet 27, the length of the unloading piston 10 extending out of the unloading piston sleeve 19 does not need to be too long, and the phenomenon that the whole grease pump head 2 is too large due to too large distance between the unloading piston 10 and the driving shaft 8 is avoided.

The unloading piston assembly 7 further comprises a touch control mechanism, the touch control mechanism comprises a touch spring 40, a piston ring sleeve 39 in sliding fit with the unloading piston 10, a potential touch ring 31 fixed on the piston ring sleeve 39 and a touch switch 30 used for being matched with the potential touch ring, the potential touch ring 31 is in sliding fit with the unloading piston 10 through the piston ring sleeve 39, the touch spring 40 is sleeved on the unloading piston 10, one end of the touch spring 40 is abutted against a stop seat 41 arranged on the unloading piston 10, the other end of the touch spring is abutted against the piston ring sleeve 39, and in order to prevent the piston ring sleeve 39 from slipping off the unloading piston 10, a stop flange is arranged at the end part of the unloading piston 10, which is positioned in the unloading piston sleeve 19. More specifically, the touch switch 30 is provided with two touch arms 301 (only one touch arm 301 is shown in the figure), the touch switch 30 is located on the cavity wall of the unloading piston sleeve inner cavity 28, when the unloading piston 10 moves to the unloading position, both touch arms 301 of the touch switch 30 are in contact with the annular potential touch ring 31, the touch switch 30 is triggered to send a trigger signal to the controller, the controller controls the motor 17 to stop rotating, and then the unloading piston 10 is kept at the unloading position until the oil pressure of the oil delivery pipe and the oil injection channel 5 is restored to the normal pressure, the touch control mechanism is not required to manually control the opening and closing of the motor 17, the operation steps are simplified, and the touch control mechanism is favorable for more accurately positioning the unloading position of the unloading piston 10. In addition, the arrangement that the potential contact ring 31 is in sliding fit with the unloading piston 10 enables the potential contact ring 31 to compress the contact spring 40 to reduce the acting force on the contact switch 30 when the unloading piston 10 moves to the unloading position, and the contact switch 30 cannot be damaged due to continuous compression of the potential contact ring 31 which moves by inertia. The potential contact ring 31 in the present exemplary embodiment forms a switch trigger arranged on the relief piston 10. In other embodiments, the switch activating member may also be a slider disposed on the unloader piston.

When the grease pump unloads high-pressure grease in an oil pipeline, the motor 17 drives the driving shaft 8 to rotate reversely, the reversely rotating driving shaft 8 drives the unloading cam to rotate reversely through the one-way bearing, the reversely rotating unloading cam enables the unloading piston 10 to move to an unloading position by jacking the unloading piston 10, at the moment, the oil drain port 26, the unloading piston sleeve inner cavity 28 and the unloading piston cavity 29 are communicated with each other, the unloading piston oil inlet hole 33 is communicated with the unloading piston cavity 29, the unloading piston oil outlet hole 34 is communicated with the oil outlet 27, and the grease in the oil filling channel 5 sequentially flows through the oil drain port 26, the unloading piston sleeve inner cavity 28, the unloading piston cavity 29, the unloading piston oil inlet hole 33, the oil drain channel 32, the unloading piston oil outlet hole 34 and the oil outlet 27 and enters the pump case inner cavity 4. Specifically, when unloading piston 10 moves to the unloading position, potential contact ring 31 will contact with contact switch 30 so that contact switch 30 is triggered and signals to the controller, motor 17 will stop rotating, and unloading piston 10 will keep the unloading position until oil pressure in oil pipeline and oil filling channel 5 returns to normal pressure. Then the motor 17 continues to drive the driving shaft 8 to rotate reversely, the unloading piston 10 is reset to the working position under the action of the unloading piston return spring 42, at this time, the piston ring sleeve 39 is in fit sealing with the wall surface of the unloading piston sleeve inner cavity 28, so that the unloading piston sleeve inner cavity 28 is disconnected from the unloading piston cavity 29, meanwhile, the unloading piston oil inlet hole 33 is disconnected from the unloading piston cavity 29, and the unloading piston oil outlet hole 34 is disconnected from the oil outlet 27.

According to the grease pump, the unloading piston assembly 7 is used for unloading high-pressure grease in the oil injection channel 5 and the oil conveying pipe, the unloading piston assembly 7 is located in the grease pump and integrated with the grease pump, an external bypass pipe and an electromagnetic valve are not needed for unloading, and the problems that the cost is high and the electromagnetic valve is easy to damage when the electromagnetic valve is used for unloading are solved.

The difference between the embodiment 2 of the grease pump of the present invention and the embodiment 1 described above is that the plug of the oil injection piston assembly is removed, and the grease pump head injects oil outwards through the oil pipe externally connected to the oil injection piston sleeve.

The embodiment 3 of the grease pump of the present invention is different from the embodiment 1 described above in that the unloading piston is driven by the unloading cam to move from the unloading position to the operating position, the outer peripheral surface of the unloading cam is provided with a sliding groove, one end of the unloading piston, which is in contact with the unloading cam, is a transmission end having a T-shaped end, the unloading cam rotates, and the sliding groove is in sliding fit with the transmission end to drive the unloading piston to move from the unloading position to the operating position.

Embodiment 4 of the grease pump of the present invention is different from embodiment 1 described above in that a crank link mechanism is provided on the drive shaft, a one-way transmission structure is provided between the crank link mechanism and the drive shaft, and the unloading piston is driven to move by the crank link mechanism when the drive shaft rotates reversely.

Embodiment 5 of the grease pump of the present invention differs from embodiment 1 described above in that the one-way transmission structure is a one-way ratchet wheel disposed between the drive shaft and the unloading cam.

Embodiment 6 of the grease pump of the present invention differs from embodiment 1 described above in that the unloading piston is not provided with a drainage channel and is a solid rod body.

In embodiment 7 of the grease pump according to the present invention, unlike embodiment 1 described above, the reverse rotation of the drive shaft is operated by a hand lever externally attached to the drive shaft, and the worker manually operates the hand lever to reverse the rotation of the drive shaft.

In the embodiment of the grease pump head of the present invention, the structure of the grease pump head is the same as that of the grease pump head described above, and the details are not repeated here.

The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention, the scope of the present invention is defined by the appended claims, and all structural changes that can be made by using the contents of the description and the drawings of the present invention are intended to be embraced therein.

Claims

1. A grease pump head, comprising:

the pump shell (3) is provided with a pump shell inner cavity (4) and an oil filling channel (5) for filling oil outwards;

an oiling piston (9);

the driving shaft (8) can drive the oil injection piston (9) to move to inject oil into the oil injection channel (5) in the forward rotation process;

the unloading device is characterized in that an unloading piston assembly (7) is further arranged in the pump shell (3), and the unloading piston assembly (7) comprises an unloading piston sleeve (19) arranged in an inner cavity (4) of the pump shell and an unloading piston (10) in sliding fit with the unloading piston sleeve (19); the unloading piston sleeve (19) is provided with an oil drainage port (26) communicated with the oil filling channel (5) and an oil outlet (27) communicated with the pump case inner cavity (4), the unloading piston (10) has an unloading position and a working position in a reciprocating motion stroke, when the unloading piston (10) is positioned at the unloading position, the oil drainage port (26) is communicated with the oil outlet (27) so that the oil filling channel (5) drains oil to the pump case inner cavity (4), and when the unloading piston (10) is positioned at the working position, the oil drainage port (26) is disconnected with the oil outlet (27) so that the oil filling channel (5) drains oil to the pump case inner cavity (4);

a one-way transmission structure is arranged between the driving shaft (8) and the unloading piston (10), and the one-way transmission structure is used for enabling the driving shaft (8) to drive the unloading piston (10) to move to an unloading position only when the driving shaft rotates reversely;

the unloading piston (10) is driven by the reverse driving shaft (8) when moving from the unloading position to the working position, or the unloading piston assembly (7) comprises a reset elastic piece providing acting force for the unloading piston (10), and the reset elastic piece can enable the unloading piston (10) to move from the unloading position to the working position when the driving shaft (8) rotates reversely.

2. A grease pump head as claimed in claim 1, characterised in that the drive shaft (8) is provided with an unloading cam, a one-way transmission arrangement is provided between the unloading cam and the drive shaft (8), and the unloading cam is used to move the unloading piston (10) when the drive shaft (8) is reversed.

3. A grease pump head as claimed in claim 2, wherein the unidirectional drive structure is a unidirectional bearing.

4. A grease pump head according to claim 2, characterised in that the unloading cam is in pushing engagement with the unloading piston (10), and when the drive shaft (8) is reversed, the unloading cam moves the unloading piston (10) to the unloading position by pressing against the unloading piston (10).

5. A grease pump head as claimed in any one of claims 1-4, wherein the return spring is an unloading piston return spring (42).

6. A grease pump head according to claim 5, characterised in that the unloading piston return spring (42) is fitted around the unloading piston (10), one end of the unloading piston return spring (42) abutting against the unloading piston sleeve (19) and the other end abutting against the end of the unloading piston (10).

7. A grease pump head according to any one of claims 1-4, characterised in that the unloading piston (10) has a drainage channel (32) for communicating the drainage port (26) with the oil outlet (27), the drainage channel (32) communicating the drainage port (26) with the oil outlet (27) when the unloading piston (10) is in the unloading position, the drainage channel (32) disconnecting the drainage port (26) from the oil outlet (27) when the unloading piston (10) is in the operating position.

8. A grease pump head according to any one of claims 1-4, characterized in that the grease pump head (2) further comprises a motor (17) for driving the driving shaft (8) in forward and reverse rotation and a controller for controlling the forward and reverse rotation of the motor (17).

9. A grease pump head as claimed in claim 8, wherein the unloading piston assembly (7) further comprises a touch switch (30), the unloading piston (10) is provided with a switch trigger, the touch switch (30) is configured to contact with the switch trigger when the unloading piston (10) moves to the unloading position and to be triggered by the switch trigger to send a trigger signal to the controller, so that the controller controls the motor (17) to stop rotating, the switch trigger is axially slidably disposed on the unloading piston (10) along the unloading piston (10), the unloading piston (10) is provided with a touch spring (40) for applying an elastic force to the switch trigger in a direction towards the touch switch (30), and when the switch trigger contacts the touch switch (30), the touch spring (40) is compressed.

10. Grease pump, comprising an oil tank (1) and a grease pump head (2), characterized in that the grease pump head (2) is a grease pump head (2) according to any one of claims 1 to 9, the oil tank (1) being adapted to supply oil to the grease pump head (2).