CN114562445A

CN114562445A - Reciprocating pump

Info

Publication number: CN114562445A
Application number: CN202210253969.4A
Authority: CN
Inventors: 徐卫华; 周财华; 童玥雯; 周良
Original assignee: DEPAMU (HANGZHOU) PUMP TECHNOLOGY CO LTD
Current assignee: DEPAMU (HANGZHOU) PUMP TECHNOLOGY CO LTD
Priority date: 2022-03-15
Filing date: 2022-03-15
Publication date: 2022-05-31
Anticipated expiration: 2042-03-15
Also published as: CN114562445B

Abstract

The invention discloses a reciprocating pump, comprising: a power section; a piston cylinder; the piston is positioned in the piston cylinder and is in transmission connection with the power part; the first supporting pipe is arranged along the vertical direction, is connected with the piston cylinder and is provided with a first through hole communicated with the piston cylinder; the first supporting pipe is provided with a feeding end and a discharging end; the first hose is arranged in the first supporting pipe, and a working cavity is formed between the first hose and the first supporting pipe; the first hose is communicated with the feeding end and the discharging end; the two one-way valves are respectively arranged at the feeding end and the discharging end; an oil supply tank. In the process of adding hydraulic oil into the piston cylinder through the oil inlet pipe, air in the piston cylinder rises and is discharged through the exhaust valve when certain pressure is reached. Avoid causing the operation unstability. During the exhaust process, part of the hydraulic oil is brought into the oil storage tank.

Description

Reciprocating pump

Technical Field

The invention relates to the technical field of hydraulic pumps, in particular to a reciprocating pump.

Background

Reciprocating pumps are positive displacement pumps that deliver or pressurize fluid by virtue of a piston, plunger or diaphragm reciprocating within a pump cylinder to alternately increase and decrease the working volume within the cylinder. The reciprocating pump is classified into 3 types of a piston pump, a plunger pump and a diaphragm pump according to reciprocating elements. When the piston moves from left to right, negative pressure is formed in the pump cylinder, and then the liquid in the storage tank enters the pump cylinder through the suction valve. When the piston moves from right to left, the liquid in the cylinder is squeezed, the pressure is increased, and the liquid is discharged through the discharge valve. The piston reciprocates once, each drawing in and expelling a single liquid cycle, referred to as a duty cycle.

In chinese patent application No.: CN202010808716.X discloses a hydraulic balance reciprocating pump, which comprises a synchronous isolation device, and comprises an isolation sleeve with an inner cavity and a piston movably arranged in the inner cavity of the isolation sleeve, wherein the periphery of the piston is in sealing fit with the inner wall of the isolation sleeve and divides the inner cavity of the isolation sleeve into a first cavity and a second cavity, the first cavity is communicated with a liquid inlet of a pump body, hydraulic oil is filled in the second cavity, an overflowing flow passage is arranged in a crosshead, a balance cavity is arranged at the position where the front end of the crosshead is connected with the rear end of a plunger, and the overflowing flow passage is communicated with the second cavity, so that the hydraulic oil in the second cavity enters the balance cavity and hydraulically acts on the rear end of the plunger. The pressure source of the hydraulic end compresses hydraulic oil through the piston in the isolation sleeve to transmit pressure to the overflowing flow passage and the balance cavity of the crosshead, and then the hydraulic oil acts on the plunger.

In chinese patent application No.: CN201510333119.5 discloses a reciprocating pump, which comprises a machine body, a motor, a crankshaft and a piston cylinder, wherein the motor is arranged on the machine body, the motor is fixedly connected with the machine body, one side of the motor is provided with a belt pulley and a belt, the belt pulley is connected with the motor in a transmission manner, the belt pulley is connected with the crankshaft in a transmission manner, the piston cylinder is arranged on one side of the machine body, the piston cylinder is fixedly connected with the machine body, a piston is arranged in the piston cylinder, the outer side of the crankshaft is provided with a bearing bush and a supporting bearing, the crankshaft is connected with a connecting rod, the crankshaft is connected with the connecting rod in a transmission manner through the bearing bush, the outer side of the bearing bush is provided with a connecting rod bolt, the connecting rod bolt is respectively in threaded connection with the connecting rod and the bearing bush, one end of the connecting rod is provided with a crosshead and a piston rod, the connecting rod is connected with the piston rod through the crosshead, and the piston rod is fixedly connected with the piston.

According to the two schemes, when the material containing particles is conveyed, the material can damage the suction pipe, the piston and the like.

In chinese patent application No.: CN200520090344.2 discloses a multistage diaphragm pump, which comprises a pump body, a speed reducer, a slider-crank mechanism connected with an output shaft of the speed reducer, and a thrust rod connected with the mechanism, wherein a plurality of butterfly diaphragms connected in series are arranged on the thrust rod arranged in a working cavity of the pump body, hydraulic media are filled in the working cavity and between two adjacent diaphragms, a first hose for conveying materials is arranged in the working cavity, two ends of the first hose are respectively connected with a feeding port and a discharging port of the pump body, and a suction check valve and a discharge check valve are arranged in the feeding port and the discharging port of the pump body.

In chinese patent application No.: CN201811120101.7 discloses a high-efficient energy-saving first hose diaphragm pump four-cylinder reciprocating drive pump accuse hydraulic system, including proportional variable pump, first electromagnetism overflow valve, first check valve, constant voltage variable pump, second electromagnetism overflow valve, second check valve, first electromagnetism direction valve, two-way proportional flow valve, third electromagnetism overflow valve, second electromagnetism direction valve, third check valve, fourth electromagnetism overflow valve, third electromagnetism direction valve. The proportional variable pump in the control system executes uniform acceleration starting, uniform motion and uniform deceleration motion according to a set periodic function to control two groups of hydraulic cylinders provided with displacement sensors, and staggered reciprocating control of four-cylinder motion is realized.

Above-mentioned two technical scheme are through carrying the material in first hose, avoid the material not with the working part direct contact of pump, avoid corroding, damage.

However, the applicant also finds that the two technical solutions have the defect that when hydraulic oil is added into the piston cylinder, air in the piston cylinder is inconvenient to exhaust, and the use is affected.

In chinese patent application No.: 202110346015.3 discloses a pulsation damper that tube bag combined together, including tube damper and bag formula attenuator, the tube damper includes the casing and sets up the hose in the casing, the hose separates interior chamber and outer cavity with the casing internal partitioning, the casing bottom is equipped with the takeover that is linked together with interior chamber, the intracavity is filled with liquid medium, the casing side is equipped with the connecting pipe, outer cavity is linked together through connecting pipe and bag formula attenuator, the switching pipe both ends are equipped with the limit valve that is used for the shutoff connecting pipe, limit valve includes stopper and valve body, be equipped with reset spring between stopper and the valve body. This technical scheme uses interior hose, outer hose, can have gas between the two, influences the use. By arranging the limit valve 301, when the material in the hose is suddenly increased, the hose rapidly extrudes the limit valve 301, which may cause the limit valve 301 to close the connecting pipe 3, and hydraulic oil cannot smoothly enter the first chamber 202. Affecting the use. During repeated use, the limit valve 301 is damaged.

In order to solve at least one of the above technical problems, the applicant has proposed the present application.

Disclosure of Invention

To solve the technical problem in at least one aspect of the background art, the invention provides a reciprocating pump.

The invention provides a reciprocating pump, which comprises:

a power section;

a piston cylinder;

the piston is positioned in the piston cylinder and is in transmission connection with the power part;

the first supporting pipe is arranged along the vertical direction, is connected with the piston cylinder and is provided with a first through hole communicated with the piston cylinder; the first supporting pipe is provided with a feeding end and a discharging end;

the first hose is arranged in the first supporting pipe, and a working cavity is formed between the first hose and the first supporting pipe; the first hose is communicated with the feeding end and the discharging end;

the two one-way valves are respectively arranged at the feeding end and the discharging end;

an oil supply tank;

the oil supply pump is communicated with the oil supply tank;

one end of the oil inlet pipe is communicated with the oil supply pump, and the other end of the oil inlet pipe is communicated with the piston cylinder;

the valve is arranged on the oil inlet pipe;

the oil storage tank is arranged at the upper part of the piston cylinder and is provided with a second through hole communicated with the piston cylinder;

and the exhaust valve is arranged in the second through hole.

Preferably, the reciprocating pump further comprises a return pipe having a bottom end communicating with the oil supply tank and a top end located in the oil storage tank.

Preferably, the top end of the return pipe is close to the bottom wall of the oil reservoir.

Preferably, a third through hole communicated with the piston cylinder is formed in the oil storage tank;

the reciprocating pump further comprises a safety valve, and the safety valve is arranged in the third through hole.

Preferably, a slag discharge hole is formed in the first supporting pipe close to the feeding end, and the slag discharge hole is communicated with the working cavity;

the reciprocating pump also comprises a plug which is detachably arranged in the slag discharging hole.

Preferably, the reciprocating pump further comprises a discharge pipe, and the first end of the discharge pipe is communicated with the discharge end; the second end of the first end is arranged along the horizontal direction; the middle part of the discharge pipe is provided with an expansion part, and the inner diameter of the expansion part is larger than that of the first end of the discharge pipe.

Preferably, the reciprocating pump further comprises:

the second supporting pipe is vertically arranged, the bottom end of the second supporting pipe is connected with the discharging pipe, and the top end of the second supporting pipe is sealed;

the second hose is arranged in the second supporting pipe, and a buffer cavity is formed between the second hose and the second supporting pipe; the bottom end of the second hose is communicated with the enlarged part, and the top end of the second hose is sealed;

a connecting pipe;

the third supporting pipe is vertically arranged, and the bottom end of the third supporting pipe is communicated with the buffer cavity through the connecting pipe;

the air bag is arranged in the third supporting tube;

an air inlet connector is communicated with the air bag.

Preferably, the reciprocating pump further comprises a protection piece, the protection piece is arranged in the third supporting pipe and located below the air bag, the third supporting pipe is divided into an upper chamber and a lower chamber, and a fourth through hole communicated with the upper chamber and the lower chamber is formed in the protection piece.

Preferably, the length direction of the fourth through hole gradually gets away from the center line of the airbag from bottom to top.

Preferably, the upper surface of the protector is a concave spherical surface.

Preferably, the number of the fourth through holes is multiple, and the fourth through holes are distributed around the center line of the airbag at intervals.

The beneficial effects brought by one aspect of the invention are as follows:

in the process of adding hydraulic oil into the piston cylinder through the oil inlet pipe, air in the piston cylinder rises and is discharged through the exhaust valve when certain pressure is reached. Avoid causing the operation unstability.

During the exhaust process, part of the hydraulic oil is brought into the oil storage tank. After the hydraulic oil is gathered to a certain height, the hydraulic oil flows back to the oil supply tank through the return pipe, so that the hydraulic oil is conveniently and repeatedly utilized, and waste is avoided.

Drawings

FIG. 1 is a front view of the present disclosure;

FIG. 2 is an axial view of the present disclosure;

FIG. 3 is an axial view of the present disclosure;

FIG. 4 is an axial view of the present disclosure;

FIG. 5 is an axial view of a fuel supply pump, fuel tank, etc. of the present disclosure;

fig. 6 is a sectional view of a fuel supply pump, a fuel storage tank, and the like, according to the present disclosure;

FIG. 7 is a cross-sectional view of a fuel supply pump, fuel tank, etc. of the present disclosure;

FIG. 8 is a cross-sectional view of a draft tube, a travel tube, etc. of the present disclosure;

FIG. 9 is a cross-sectional view of a draft tube, a traveling tube, etc. of the present disclosure;

FIG. 10 is an enlarged cross-sectional view of a flow conduit according to the present disclosure;

FIG. 11 is an axial view of the present disclosure;

FIG. 12 is an axial view of a first support tube or the like disclosed in the present invention

FIG. 13 is a cross-sectional view of a discharge conduit, a second support conduit, etc. of the present disclosure;

FIG. 14 is a cross-sectional view of a discharge conduit, a second support conduit, etc. of the present disclosure;

FIG. 15 is a cross-sectional view of a third support tube and the like disclosed herein;

FIG. 16 is a cross-sectional view of a third support tube and the like disclosed herein;

fig. 17 is a sectional view of a connection pipe and the like disclosed in the present invention.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments in the present application may be combined with each other; the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", and "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, only for convenience of description and simplification of description, but do not indicate or imply that the positions or elements referred to must have specific orientations, be constructed in specific orientations, and operate, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Referring to fig. 1 to 17, the present invention provides a reciprocating pump including:

a power section 1; a piston cylinder 2; and the piston 3 is positioned in the piston cylinder 2 and is in transmission connection with the power part 1. The power part 1 can be a crank connecting rod mechanism and drives the piston 3 to move back and forth in the piston cylinder 2.

The first supporting pipe 4 is arranged along the vertical direction, is connected with the piston cylinder 2 and is provided with a first through hole 401 communicated with the piston cylinder 2; the first support tube 4 has an inlet end 402, an outlet end 403.

A first hose 5, which is arranged in the first supporting tube 4, and forms a working cavity G with the first supporting tube 4; the first hose 5 is communicated with the feeding end 402 and the discharging end 403.

The two check valves 6 are respectively arranged at the feeding end 402 and the discharging end 403; an oil supply tank 7; an oil supply pump 8 communicated with the oil supply tank 7; and one end of the oil inlet pipe 9 is communicated with the oil supply pump 8, and the other end of the oil inlet pipe is communicated with the piston cylinder 2.

A valve 10 mounted on the oil inlet pipe 9; the oil storage tank 11 is arranged at the upper part of the piston cylinder 2 and is provided with a second through hole communicated with the piston cylinder 2; and an exhaust valve 12 arranged in the second through hole.

Referring to fig. 6, the oil supply pump 8 is turned on, the valve 10 is opened, and the hydraulic oil is transferred from the oil supply tank 7 into the piston cylinder 2, and then enters the working chamber G through the first through hole 401. Then, the valve 10 is closed and the fuel feed pump 8 is stopped.

When the power part 1 drives the piston 3 to move leftwards, the pressure in the working cavity G is reduced, the first hose 5 expands outwards, and external materials enter the first hose 5 through the check valve 6 below under the action of pressure difference.

When the power part 1 drives the piston 3 to move rightwards, the pressure in the working cavity G is increased, the hydraulic oil extrudes the first hose 5, and materials are discharged through the upper one-way valve 6. The material conveying is realized by repeating the steps. The material is conveyed in the first hose 5 to avoid corrosion of the first support tube 4.

When the oil inlet pipe 9 is used for adding hydraulic oil into the piston cylinder 2, air in the piston cylinder 2 rises and is discharged through the exhaust valve 12 when certain pressure is reached. Avoiding the unstable operation.

The reciprocating pump further comprises a return pipe 13, the bottom end of the return pipe 13 being in communication with the oil supply tank 7 and the top end thereof being located in the oil storage tank 11.

During the venting process, a portion of the hydraulic oil is carried into the oil reservoir 11. When the hydraulic oil is gathered to a certain height, the hydraulic oil flows back to the oil supply tank 7 through the return pipe 13, so that the hydraulic oil is convenient to recycle and is prevented from being wasted.

As a further improvement of the above embodiment, in one embodiment, the top end of the return pipe 13 is close to the bottom wall of the oil reservoir 11. So set up, avoid the air to get into the back flow 13, make things convenient for hydraulic oil backward flow to supply tank 7.

As a further improvement of the above embodiment, in one embodiment, the oil reservoir 11 is provided with a third through hole communicating with the piston cylinder 2; the reciprocating pump further comprises a relief valve 14, the relief valve 14 being arranged in the third through hole. When the pressure in the piston cylinder 2 is too high, for example, materials are blocked in the first hose 5, and the piston 3 moves rightwards, the pressure is conveniently and timely released by arranging the safety valve 14. The discharged hydraulic oil flows into the oil storage tank 11 and conveniently flows back into the oil supply tank 7.

As a further improvement to the above example, in one embodiment, the first supporting tube 4 is provided with a slag discharge hole 404 near the feeding end 402, and the slag discharge hole 404 is communicated with the working chamber G; the reciprocating pump further comprises a plug 15, and the plug 15 is detachably arranged in the slag discharge hole 404. After a period of use, the plug 15 is opened and the hydraulic oil collected near the feed end 402 is drained of a portion having impurities. Avoiding damage. And then supplementing hydraulic oil.

As a further improvement to the above-described embodiment, in one embodiment, the reciprocating pump further comprises a discharge pipe 16, a first end of which communicates with the discharge end 403; the second end of the first end is arranged along the horizontal direction; wherein, the middle part of the discharge pipe 16 is provided with an enlarged part 1601, and the inner diameter of the enlarged part 1601 is larger than the inner diameter of the first end and the second end of the discharge pipe 16.

The material is discharged through first hose 5 interval, through setting up row material pipe 16 to form expansion portion 1601, let the internal diameter of expansion portion 1601 be greater than the internal diameter of the first end of row material pipe 16, so set up, when the material gets into expansion portion 1601, have certain buffering, regulation effect, then the material is discharging through the second end of arranging material pipe 16, and discharge flow is comparatively even.

As a further refinement of the above embodiment, in one embodiment, the reciprocating pump further comprises:

a second support pipe 17 arranged vertically, the bottom end of which is connected with the discharge pipe 16 and the top end of which is sealed; the second supporting tube is provided with a detachable sealing plug M; a second hose 18 disposed inside the second support pipe 17, forming a buffer chamber H with the second support pipe 17; the second hose 18 has a bottom end communicating with the enlarged portion 1601 and a top end sealed. The sealing plug M on the second support pipe 17 is opened, and hydraulic oil is added into the buffer chamber H. And then the sealing plug M is installed.

A connecting pipe 19; a third support tube 20 vertically arranged with its bottom end communicating with the buffer chamber H through the connection tube 19; an air bag 21 disposed in the third support tube 20; an air inlet connector 22 is communicated with the air bag 21. The airbag 21 is inflated through the intake connector 22 by an external device.

With reference to fig. 12-16, when the flow of the material in the expanding portion 1601 is large, the material enters the second flexible tube 18 and presses the second flexible tube 18, and the hydraulic oil in the buffer chamber H enters the third support tube 20 through the connecting tube 19 and presses the air bag 21.

When the flow rate of the material in the expansion portion 1601 is small, the material flows back to the expansion portion 1601. The air bag 21 presses the hydraulic oil into the cushion chamber H. So, can arrange the flow of the material of expecting 16 discharge pipes and carry out the equilibrium, let the flow more even.

As a further improvement of the above embodiment, in one embodiment, the reciprocating pump further includes a protector 23 disposed in the third support tube 20 and below the air bag 21, and dividing the third support tube 20 into an upper chamber 2002 and a lower chamber 2001, and the protector 23 is provided with a fourth through hole 2301 communicating the upper chamber 2002 and the lower chamber 2001.

After entering the lower chamber 2001, the hydraulic oil enters the upper chamber 2002 through the fourth through hole 2301, and presses the air bag 21. When the pressure in the buffer chamber H is reduced, the air bag 21 is expanded to press the hydraulic oil, and the hydraulic oil in the upper chamber 2002 flows back to the lower chamber 2001 through the fourth through hole 2301.

The protection member 23 is provided to prevent the hydraulic oil from directly impacting the air bag 21 and damaging the air bag 21. The flow speed of hydraulic oil can be stabilized, and the discharge flow of materials is stabilized.

As a further improvement of the above embodiment, in one embodiment, the length direction of the fourth through hole 2301 gradually gets away from the center line of the airbag 21 from the bottom to the top. The hydraulic oil is prevented from directly impacting the air bag 21, and the air bag 21 is prevented from being damaged.

As a further improvement of the above embodiment, in one embodiment, the upper surface of the protection member 23 is a concave spherical surface. When the airbag 21 inflates, the bottom of the airbag 21 contacts and contacts the upper surface of the protector 23, thereby protecting the airbag 21.

As a further improvement of the above embodiment, in one embodiment, the number of the fourth through holes 2301 is multiple, and the fourth through holes are spaced around the center line of the airbag 21. The hydraulic oil is convenient to pass through. Avoiding impact on the air bag 21.

The middle portion of the lower surface of the protector 23 is an upwardly concave spherical surface. When the hydraulic oil rapidly enters the lower chamber 2001, most of the hydraulic oil contacts the middle of the lower surface of the protection member 23, and the hydraulic oil is dispersed downward and around the middle of the lower surface of the protection member 23. When the hydraulic oil reaches a certain amount, the hydraulic oil enters the upper chamber 2002 through the fourth through hole 2301.

So set up, can stabilize the functioning speed of hydraulic oil, stabilize the material discharge flow. Direct impact on the airbag 21 is also avoided.

In order to further stabilize the discharge flow of the material, a buffer block 27 is provided in the connecting pipe 19, and an end of the buffer block 27 adjacent to the second hose 18 has a concave arc surface. So, when hydraulic oil moves along connecting pipe 19 fast, can play the effect of buffering hydraulic oil translation rate, stabilize material discharge flow homogeneity.

The upper surface of the buffer block 27 is an inclined surface arranged downwards, so that hydraulic oil can flow back conveniently.

This embodiment may be further modified, although it will be appreciated by those skilled in the art that such modifications are not required and are merely preferred. The improvement is as follows:

with reference to fig. 8-10, hydraulic oil is lost during use by providing the fifth through hole 405 in the first support tube 4. A moving tube 24 is provided in the fifth through hole 405. The inner wall of the moving tube 24 is provided with a groove 2401, and the groove 2401 may be annular and is disposed near the outer end of the moving tube 24.

A flow guide tube 25 is also provided in this embodiment, and has a first end communicating with the feed pump 8 and a second end penetrating into the movable tube 24, and a second end sealed. The wall of the guide pipe 25 is provided with an oil guide hole 2501. Wherein the moving tube 24 can move along the flow guide tube 25. At the beginning, the oil guide hole 2501 is sealed by the inner wall of the moving pipe 24, and the hydraulic oil in the flow guide pipe 25 cannot enter the recess 2401.

A spring 26 is provided on the draft tube 25, and one end thereof is fixed to the draft tube 25 and the other end thereof is fixed to the moving tube 24.

When the first hose 5 expands outwards to contact with the moving pipe 24, the moving pipe 24 is pushed to move outwards against the elastic force of the spring 26, after the first hose moves to a certain position, the groove 2401 is communicated with the oil guide hole 2501, and hydraulic oil in the flow guide pipe 25 enters the working cavity G through the flow guide hole, the groove 2401 and the moving pipe 24 to be supplemented with hydraulic oil.

When the hydraulic oil in the working chamber G is replenished, the first hose 5 does not come into contact with the flow guide tube 25 even when it expands. Under the urging of the spring 26, the moving tube 24 is reset, the recess 2401 is separated from the oil guide hole 2501, and the oil guide hole 2501 is resealed.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. A reciprocating pump, comprising:

a power section;

a piston cylinder;

an oil supply tank;

the oil supply pump is communicated with the oil supply tank;

the valve is arranged on the oil inlet pipe;

an exhaust valve arranged in the second through hole;

and the bottom end of the return pipe is communicated with the oil supply tank, and the top end of the return pipe is positioned in the oil storage tank.

2. The reciprocating pump of claim 1, wherein a top end of the return tube is adjacent to a bottom wall of the reservoir.

3. The reciprocating pump of any one of claims 1-2, wherein the oil reservoir is provided with a third through hole communicating with the piston cylinder;

4. The reciprocating pump of claim 1, wherein the first support tube is provided with a deslagging aperture proximate the feed end, the deslagging aperture being in communication with the working chamber;

5. The reciprocating pump of claim 1, further comprising a discharge tube having a first end in communication with the discharge end; the second end of the first end is arranged along the horizontal direction; the middle part of the discharge pipe is provided with an expansion part, and the inner diameter of the expansion part is larger than that of the first end of the discharge pipe.

6. The reciprocating pump of claim 5, further comprising:

the second supporting pipe is vertically arranged, the bottom end of the second supporting pipe is connected with the discharging pipe, and the top end of the second supporting pipe is sealed; a detachable sealing plug is arranged on the second supporting tube;

a connecting pipe;

the air bag is arranged in the third supporting tube;

an air inlet connector is communicated with the air bag.

7. The reciprocating pump of claim 6, further comprising a protector disposed in the third support tube below the air bag and dividing the third support tube into an upper chamber and a lower chamber, wherein the protector is provided with a fourth through hole communicating the upper chamber and the lower chamber.

8. The reciprocating pump of claim 7, wherein the length direction of the fourth through hole gradually gets away from the center line of the air bag from bottom to top.

9. The reciprocating pump of claim 7 or 8, wherein the upper surface of the protecting member is a concave spherical surface.

10. The reciprocating pump of claim 7 or 8, wherein the number of the fourth through holes is a plurality of the fourth through holes, and the fourth through holes are distributed around the center line of the air bag at intervals.