Multi-cylinder single-action reciprocating fertilization pump

Abstract

The invention discloses a multi-cylinder single-action reciprocating fertilization pump, and belongs to the technical field of agricultural mechanical equipment. The modularized pump body is formed by combining multi-cylinder pump bodies, the modularized pump body is installed on the modularized pump head body, a piston element is arranged in each working cavity corresponding to the multi-cylinder pump body, the stroke volumes of the multiple piston elements in the corresponding working cavities are equal, and phase angles are staggered by 0-180 degrees; a liquid inlet and a liquid outlet which are communicated with the corresponding working cavities of the multi-cylinder pump body are formed in the modularized pump head body; the bidirectional offset crank connecting rod mechanism is provided with an optimal transmission angle, and the bidirectional offset crank connecting rod mechanism serves as a driving power end and is in driving connection with a piston element of the three-cylinder pump body so as to drive the piston element to do reciprocating rectilinear motion in the corresponding working cavity; and the valves are mounted at the liquid inlet and the liquid outlet. The multi-cylinder single-action reciprocating type fertilization pump has the advantages of being excellent in force transmission performance, flexible in combination, high in transmission efficiency and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural machinery and equipment, and in particular relates to a multi-cylinder single-acting reciprocating fertilizer pump. Background Art

[0002] A reciprocating fertilizer pump is a type of agricultural water-fertilizer integrated machinery. It relies on the piston, plunger or rubber diaphragm to make reciprocating motion in the pump cylinder to alternately increase and decrease the working volume in the pump cylinder to inject the configured fertilizer liquid into the field or into the irrigation main pipeline to carry out field fertilization along with irrigation water.

[0003] At present, in addition to the reciprocating fertilizer injection pumps used in large irrigation areas with high construction costs, the most widely used fertilization equipment on the market is the Venturi fertilizer applicator. The Venturi fertilizer applicator is limited by its inherent defects. As a fertilization equipment, it has problems such as low fertilizer absorption, high starting pressure, large head pressure loss, easy fluctuation of fertilizer concentration, and inability to accurately apply fertilizer. The reciprocating pump has the advantages of high efficiency, wear resistance, corrosion resistance, high pressure resistance, and easy flow control. There are two prominent problems with the existing reciprocating fertilizer injection equipment on the market:

[0004] (1) There is a lack of reciprocating pumps for agricultural applications. For example, existing reciprocating pumps are mainly optimized for industrial high-pressure conditions (over 3MPa), but not for agricultural application scenarios (less than 1.0Mpa). At the same time, existing reciprocating pumps are not suitable for low-pressure conditions of agricultural fertilization (working in a lower efficiency range, deviating from the high efficiency range), and have problems such as low mechanical efficiency and large space occupation (not lightweight). Even in large irrigation areas, reciprocating fertilizer injection pumps have the problem of operating conditions deviating from the optimal efficiency range.

[0005] (2) There is still room for improvement in existing reciprocating pumps, such as a) lightweighting (optimizing force transmission, lightweighting of moving parts such as crankshafts, plungers, and connecting rods); b) reducing wear (optimizing force transmission, optimizing friction surface mechanics, etc.); c) increasing the single-action volume and improving the "mass efficiency" (ratio of the mass of the liquid being transported to the total mass (liquid mass + mass of moving parts)) during a single action of transporting liquid. Summary of the invention

[0006] In order to solve the above problems, the present invention adopts the following technical solutions:

[0007] A multi-cylinder single-acting reciprocating fertilizer pump, comprising:

[0008] Modular pump head body;

[0009] A modular pump body composed of a multi-cylinder pump body, the modular pump body is installed on the modular pump head body, a piston element is arranged in each corresponding working chamber of the multi-cylinder pump body, the stroke volumes of the multiple piston elements in the corresponding working chamber are equal, and the phase angles are staggered by 0-180°; the modular pump head body is equipped with a liquid inlet and a liquid outlet connected to the corresponding working chamber of the multi-cylinder pump body;

[0010] A bidirectional offset crank-connecting rod mechanism with an optimal transmission angle, the bidirectional offset crank-connecting rod mechanism serving as a driving power end, drivingly connected to the piston element of the multi-cylinder pump body to drive the piston element to reciprocate linearly in a corresponding working chamber;

[0011] A valve is installed at the liquid inlet and the liquid outlet.

[0012] Furthermore, the bidirectional offset crank-connecting rod mechanism comprises:

[0013] A plurality of eccentric wheels, wherein the mutual angle between the plurality of eccentric wheels is 360° / the number of the piston elements;

[0014] A transmission rod passing through the plurality of eccentric wheels;

[0015] A plurality of piston crossheads, wherein the plurality of piston crossheads are arranged in one-to-one correspondence with the plurality of piston elements and connected with the corresponding piston elements;

[0016] A plurality of integral connecting rods, wherein the plurality of connecting rods are arranged in one-to-one correspondence with the plurality of eccentric wheels and the plurality of piston cross heads, wherein the large end of the connecting rod is connected to the eccentric wheel, and the small end of the connecting rod is connected to the piston cross head pin;

[0017] Wherein, under the action of the connecting rod, the rotational motion of the eccentric wheel is converted into the reciprocating linear motion of the piston element connected to one end of the small end of the connecting rod.

[0018] Furthermore, the eccentric wheel is located in the big end of the connecting rod and is rotatably connected to the big end of the connecting rod.

[0019] Furthermore, the eccentric wheel is lower than the rotation center line of the piston crosshead to reduce the positive pressure of the piston crosshead on the cylinder body of the multi-cylinder pump body.

[0020] Furthermore, the calculation formula between the optimal transmission angle, the reciprocating motion stroke of the slider, and the crank length is:

[0021]

[0022] Pole angle:

[0023] Where, H is the reciprocating stroke of the crosshead piston;

[0024] a is the crank length;

[0025] b is the connecting rod length;

[0026] K = 1.1;

[0027] Among them, the connecting rod length and crank length satisfy:

[0028] Offset:

[0029] When the motion stroke and stroke speed ratio are known, the extreme value and extreme value point of the above γ formula can be obtained by using the golden section method, and the combination of parameters a, b, and e of the bidirectional offset crank-connecting rod mechanism with the optimal transmission angle can be obtained.

[0030] Furthermore, the piston element is a rubber piston, and the rubber piston is assembled in the corresponding working cavity of the multi-cylinder pump body through interference fit.

[0031] Furthermore, the valve is an electromagnetic ball one-way valve or an electromagnetic / mechanical two-way valve.

[0032] Furthermore, the electromagnetic ball one-way valve comprises:

[0033] The valve seat is a cylindrical structure with a completely through cavity in the middle, and a shrinking chamfer is provided in the cavity; an electromagnet is provided at the lower end of the valve seat;

[0034] A sphere with a hollow interior, the sphere is placed in the cavity of the valve seat and is provided with a chamfer in the cavity to form a line contact;

[0035] A guide sleeve is connected to one end of the valve seat close to the sphere, and a lift limiter is arranged inside the guide sleeve to limit the lift of the sphere.

[0036] Furthermore, the sphere is an iron bead.

[0037] Furthermore, a groove is provided at the lower end of the valve seat, and the electromagnet is placed in the groove.

[0038] Beneficial effects:

[0039] 1. The multi-cylinder single-acting reciprocating fertilizer pump provided by the present invention improves the distance between the rotation center line of the eccentric wheel and the rotation center line of the crosshead, thereby improving the force transmission performance of the crank-connecting rod mechanism on the one hand, and on the other hand, reduces the positive pressure between the crosshead piston and the lower cylinder body, reduces the friction between the crosshead piston and the cylinder body, and improves the transmission efficiency of the reciprocating pump.

[0040] 2. The electromagnetic ball one-way valve provided by the present invention reduces the weight of the iron ball, speeds up the rising speed of the iron ball, generates magnetic force by energizing the electromagnet, and accelerates the falling speed of the iron ball; it reduces the influence of the valve opening and closing lag angle on the volumetric efficiency of the reciprocating pump and the accuracy of fertilization when the traditional one-way valve is working. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of the overall structure of a multi-cylinder single-acting reciprocating fertilizer pump provided by the present invention;

[0042] Figure 2 A top view of a multi-cylinder single-acting reciprocating fertilizer pump provided by the present invention;

[0043] Figure 3 for Figure 3 Schematic diagram of the AA section;

[0044] Figure 4 It is a structural schematic diagram of an electromagnetic ball check valve;

[0045] Figure 5 It is a front view of the electromagnetic ball check valve;

[0046] Figure 6 for Figure 5 Schematic diagram of the middle BB section;

[0047] Figure 7 It is the geometric relationship diagram between the limit position and the optimal transmission angle position of the crank-connecting rod mechanism;

[0048] Among them, 1. Modular pump head body; 2. Three-cylinder pump body; 3. Bidirectional offset crank-connecting rod mechanism; 31. Transmission rod; 32. Eccentric wheel; 33. Connecting rod; 4. Discharge port; 5. Electromagnetic ball check valve; 51. Valve seat; 52. Ball; 53. Guide sleeve; 54. Lift limiter; 55. Chamfer; 56. Groove; 6. Liquid inlet; 7. Piston crosshead; 8. Piston element; 9. Working chamber. DETAILED DESCRIPTION

[0049] Example 1

[0050] refer to Figure 1 - Figure 6 , a multi-cylinder single-acting reciprocating fertilizer pump, comprising:

[0051] Modular pump head body 1;

[0052] A modular pump body composed of a multi-cylinder pump body, the modular pump body is installed on a modular pump head body, a piston element is arranged in each corresponding working chamber of the multi-cylinder pump body, the stroke volumes of the multiple piston elements in the corresponding working chamber are equal, and the phase angles are staggered by 0-180°; a liquid inlet and a liquid discharge port connected to the corresponding working chamber of the multi-cylinder pump body are installed on the modular pump head body;

[0053] A bidirectional offset crank-connecting rod mechanism with an optimal transmission angle, the bidirectional offset crank-connecting rod mechanism serving as a driving power end, drivingly connected to a piston element of a multi-cylinder pump body, so as to drive the piston element to reciprocate linearly in a corresponding working chamber;

[0054] Valves are installed at the liquid inlet and outlet.

[0055] In this embodiment, the bidirectional offset crank-connecting rod mechanism 3 comprises:

[0056] A plurality of eccentric wheels 32, wherein the mutual angle of the plurality of eccentric wheels 32 is 360° / the number of piston elements 8;

[0057] A transmission rod 31 passing through a plurality of eccentric wheels 32;

[0058] A plurality of piston crossheads 7, the plurality of piston crossheads 7 are arranged in one-to-one correspondence with the plurality of piston elements 8, and are connected with the corresponding piston elements 8;

[0059] A plurality of integral connecting rods 33, wherein the plurality of connecting rods 33 are arranged in one-to-one correspondence with the plurality of eccentric wheels 32 and the plurality of piston cross heads 7, wherein the large end of the connecting rod 33 is connected to the eccentric wheel, and the small end of the connecting rod 33 is pin-connected to the piston cross head 7;

[0060] Under the action of the connecting rod 33 , the rotational motion of the eccentric wheel 32 is converted into the reciprocating linear motion of the piston element 8 connected to the small end of the connecting rod 33 .

[0061] In this embodiment, the modular pump body can be freely combined with 1-6 cylinder pump bodies. In this embodiment, a three-cylinder pump body is taken as an example for illustration.

[0062] Specifically, the three-cylinder pump body 2 is mounted on the modular pump head body 1, and a piston element 8 is disposed in each of the three working chambers 9 of the three-cylinder pump body 2. The stroke volumes of the three piston elements 8 in the corresponding working chambers 9 are equal, and the phase angles are staggered by 120°. The modular pump head body 1 is provided with a liquid inlet 6 and a liquid outlet 4 connected to the working chamber 9 of the three-cylinder pump body 2;

[0063] The bidirectional offset crank-connecting rod mechanism 3 serves as a driving power end and is drivingly connected to the piston element 8 of the three-cylinder pump body 2 to drive the piston element 8 to reciprocate linearly in the corresponding working chamber 9.

[0064] Specifically, in order to correspond to the three-cylinder pump body 2, the bidirectional offset crank-connecting rod mechanism 3 in this embodiment includes:

[0065] 3 eccentric wheels 32 with a mutual angle of 120°;

[0066] A transmission rod 31 passing through three eccentric wheels 32;

[0067] Three piston crossheads 7, the three piston crossheads 7 are arranged in one-to-one correspondence with the three piston elements 8, and are connected to the corresponding piston elements 8;

[0068] Three integral connecting rods 33, the three connecting rods 33 are arranged in one-to-one correspondence with the three eccentric wheels 32 and the three piston cross heads 7, wherein the large end of the connecting rod 33 is connected to the eccentric wheel 32, and the small end of the connecting rod 33 is pin-connected to the piston cross head 7;

[0069] Under the action of the connecting rod 33 , the rotational motion of the eccentric wheel 32 is converted into the reciprocating linear motion of the piston element 8 connected to the small end of the connecting rod 33 .

[0070] In this embodiment, the eccentric wheel 32 is located in the big end of the connecting rod 33 and is rotatably connected to the big end of the connecting rod 33 .

[0071] The multi-cylinder single-acting reciprocating fertilizer pump provided in this embodiment causes the reciprocating motion of the piston element 8 to cause the volume of the pump body working chamber 9 to change, thereby generating negative pressure and completing the suction and discharge of fertilizer liquid.

[0072] In this embodiment, a pump body cover for installing water inlet and outlet pipes and installing a control valve pump body cover is provided with a converging flow channel to achieve drag reduction, including reducing the fluid flow resistance in the pump cover flow channel, reducing the control valve resistance, etc.

[0073] In this embodiment, the power required for the fertilizer pump is provided by a three-phase motor and a reduction gear box connected to the three-phase motor, and the output end of the reduction gear box is drivingly connected to the transmission rod 31.

[0074] When working, the motor acts as a power source to provide the power required for the entire water pump to work. The motor drives the eccentric wheel 32 to rotate by rotating the driving gear. The eccentric wheel 32 is rotatably connected to the large end of the connecting rod 33 through a needle bearing. Under the action of the connecting rod 33, the rotational motion of the eccentric wheel 32 is converted into the reciprocating linear motion of the crosshead piston connected to the small end of the connecting rod 33.

[0075] In this embodiment, the eccentric wheel 32 is lower than the rotation center line of the piston crosshead 7 to reduce the positive pressure of the piston crosshead 7 on the cylinder body of the three-cylinder pump body 2.

[0076] In addition, in order to improve working efficiency, the resistance of the reciprocating piston and connecting rod mechanism contained in the pump body can be reduced, such as enhancing lubrication, optimizing temperature control, etc., or adjusting the cylinder diameter ratio to optimize the pumping efficiency; the resistance of the reciprocating motion of the piston driven by the bidirectional offset crank-connecting rod mechanism can be reduced, such as enhancing lubrication, lightweighting, sacrificing suction efficiency to improve pumping efficiency, etc.

[0077] refer to Figure 7 The transmission angle is an important basis for measuring the force transmission performance of the mechanism. When designing, a bidirectional offset crank-connecting rod mechanism 3 with an optimal transmission angle is designed to improve the force transmission performance of the crank-connecting rod mechanism.

[0078] In this embodiment, the calculation formula between the optimal transmission angle, the reciprocating motion stroke of the slider, and the crank length is:

[0079]

[0080] Pole angle:

[0081] Where, H is the reciprocating stroke of the crosshead piston;

[0082] a is the crank length;

[0083] b is the connecting rod length;

[0084] K = 1.1;

[0085] Among them, the length of the connecting rod 33 and the length of the crank satisfy:

[0086] Offset:

[0087] Among them, C' is the point where the transmission angle of the slider's reciprocating motion stroke is the smallest;

[0088] When the motion stroke H = 0.03m, K = 1.1, the extreme value and extreme point of the above γ formula are obtained by using the golden section method, and the combination of parameters a, b, and e of the bidirectional offset crank-connecting rod mechanism with the optimal transmission angle can be obtained.

[0089] This embodiment changes the transmission mode of the concentric crank-connecting rod mechanism of the traditional reciprocating fertilizer pump and adopts a bidirectional offset crank-connecting rod mechanism with the optimal transmission angle. The bidirectional offset crank-connecting rod mechanism can effectively reduce the positive pressure and eccentric wear of the piston crosshead on the cylinder body and extend the service life of the crosshead and the cylinder body. The crank-connecting rod mechanism usually uses the transmission angle as the basis for measuring the transmission performance of the mechanism. When the reciprocating stroke remains unchanged, the relationship between the crank length and the transmission angle is a single-peak function.

[0090] For the unimodal function, the golden section algorithm is used to optimize the size parameters of the crank-connecting rod mechanism. Based on this optimization design, the size parameters of the bidirectional offset crank-connecting rod mechanism with the optimal transmission angle are obtained to further improve the transmission efficiency of the fertilizer pump.

[0091] In this embodiment, the piston element 8 is a rubber piston, and the rubber piston is assembled in the corresponding working chamber 9 of the three-cylinder pump body 2 by interference fit.

[0092] This embodiment is designed to be lightweight and simplified based on the existing reciprocating pump; a rubber piston head with an interference fit with the cylinder body is used to replace the plunger on the existing reciprocating pump, thereby meeting the low-pressure environment of agricultural fertilization, so as to provide a reciprocating fertilizer injection pump that can meet the low-pressure working conditions during agricultural fertilization operations.

[0093] The working principle of the multi-cylinder single-acting reciprocating fertilizer pump provided in this embodiment is as follows:

[0094] The plunger at the hydraulic end of the reciprocating fertilizer injection pump is connected to the bidirectional offset crank-connecting rod mechanism at the power end, and reciprocates under the drive of the bidirectional offset crank-connecting rod mechanism. The plunger reciprocating in the hydraulic chamber forces the pressure of the hydraulic oil in the chamber to change regularly through extrusion. The hydraulic diaphragm undergoes regular flexural deformation between the limiting plates of the working chamber 9 under the action of the hydraulic oil pressure, and the volume of the working chamber 9 changes, generating negative pressure. In combination with the opening and closing of the suction and discharge valves, the suction and discharge of liquid fertilizer are completed.

[0095] In order to reduce the influence of the valve opening and closing hysteresis angle on the volumetric efficiency of the reciprocating pump and the fertilization accuracy when the traditional one-way valve is working, in this embodiment, the valve is an electromagnetic ball one-way valve or an electromagnetic / mechanical two-way valve, preferably an electromagnetic ball one-way valve.

[0096] Specifically, in this embodiment, the electromagnetic ball check valve 5 includes:

[0097] The valve seat 51 is a cylindrical structure, with a completely through cavity in the middle, and a shrinking chamfer 55 in the cavity; an electromagnet is provided at the lower end of the valve seat 51;

[0098] A sphere 52 having a hollow interior, the sphere 52 is placed in the cavity of the valve seat 51 and is provided with a chamfer 55 in the cavity to form a line contact;

[0099] The guide sleeve 53 is connected to one end of the valve seat 51 close to the ball 52 . A lift limiter 54 is arranged inside the guide sleeve 53 to limit the lift of the ball 52 .

[0100] Specifically, the sphere 52 is preferably an iron bead with a hollow interior; the chamfer 55 in the cavity is preferably a 45° chamfer.

[0101] In this embodiment, a groove 56 is provided at the lower end of the valve seat 51 , and an electromagnet is placed in the groove 56 .

[0102] In addition, work efficiency can be improved by controlling the direction of fluid flow in the pump cover, fine control, drag reduction, and lightweighting.

[0103] Working principle of the electromagnetic ball check valve in the multi-cylinder single-acting reciprocating fertilizer pump provided in this embodiment:

[0104] Sensors are respectively installed at the end points of the suction and discharge strokes of the reciprocating fertilizer injection pump.

[0105] When the reciprocating pump plunger is at the end point of the liquid discharge stroke, the circuit is closed to form a passage, the electromagnetic coil on the valve seat 51 of the electromagnetic ball check valve 5 at the liquid discharge port 4 is energized, and the valve ball quickly forms a line contact with the chamfer 55 on the upper part of the valve seat 51 under the action of the electromagnetic force, the liquid discharge valve is quickly closed, and the reciprocating fertilizer injection pump starts to absorb liquid. Similarly, when the reciprocating fertilizer injection pump is at the end point of the liquid absorption stroke, the electromagnetic coil on the valve seat 51 of the electromagnetic ball check valve 5 at the liquid absorption port is energized, the liquid absorption valve is quickly closed, and the reciprocating fertilizer injection pump starts to discharge liquid. The liquid absorption and discharge process reaches a cycle of reciprocating.

[0106] The multi-cylinder pump provided by the present invention is an improvement on the existing reciprocating pump, and its purpose is to enable it to be used for agricultural fertilization, specifically to improve working efficiency (lightweight, drag reduction, and optimized pumping efficiency), optimize volume weight (lightweight and miniaturization), and reduce overall costs (manufacturing, transportation, procurement, use, and maintenance).

[0107] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A multi-cylinder single-acting reciprocating fertilizer pump, characterized in that: include: Modular pump head body; A modular pump body composed of a multi-cylinder pump body, the modular pump body is installed on the modular pump head body, a piston element is arranged in each corresponding working chamber of the multi-cylinder pump body, the stroke volumes of the multiple piston elements in the corresponding working chamber are equal, and the phase angles are staggered by 0-180°; the modular pump head body is equipped with a liquid inlet and a liquid outlet connected to the corresponding working chamber of the multi-cylinder pump body; A bidirectional offset crank-connecting rod mechanism with an optimal transmission angle, the bidirectional offset crank-connecting rod mechanism serving as a driving power end, drivingly connected to the piston element of the multi-cylinder pump body to drive the piston element to reciprocate linearly in a corresponding working chamber; A valve is installed at the liquid inlet and the liquid outlet.

2. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 1, characterized in that: The bidirectional offset crank-connecting rod mechanism comprises: A plurality of eccentric wheels, wherein the mutual angle between the plurality of eccentric wheels is 360° / the number of the piston elements; A transmission rod passing through the plurality of eccentric wheels; A plurality of piston crossheads, wherein the plurality of piston crossheads are arranged in one-to-one correspondence with the plurality of piston elements and connected with the corresponding piston elements; A plurality of integral connecting rods, wherein the plurality of connecting rods are arranged in one-to-one correspondence with the plurality of eccentric wheels and the plurality of piston cross heads, wherein the large end of the connecting rod is connected to the eccentric wheel, and the small end of the connecting rod is connected to the piston cross head pin; Wherein, under the action of the connecting rod, the rotational motion of the eccentric wheel is converted into the reciprocating linear motion of the piston element connected to one end of the small end of the connecting rod.

3. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 2, characterized in that: The eccentric wheel is located in the big end of the connecting rod and is rotatably connected to the big end of the connecting rod.

4. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 3, characterized in that: The eccentric wheel is lower than the rotation center line of the piston crosshead to reduce the positive pressure of the piston crosshead on the cylinder body of the multi-cylinder pump body.

5. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 4, characterized in that: The calculation formula between the optimal transmission angle, the reciprocating stroke of the slider, and the crank length is: Pole angle: Where, H is the reciprocating stroke of the crosshead piston; a is the crank length; b is the connecting rod length; K＝1.1； Among them, the connecting rod length and crank length satisfy: Offset: When the motion stroke and stroke speed ratio are known, the extreme value and extreme value point of the above γ formula can be obtained by using the golden section method, and the combination of parameters a, b, and e of the bidirectional offset crank-connecting rod mechanism with the optimal transmission angle can be obtained.

6. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 1, characterized in that: The piston element is a rubber piston, and the rubber piston is assembled in the corresponding working cavity of the multi-cylinder pump body through interference fit.

7. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 1, characterized in that: The valve is an electromagnetic ball one-way valve or an electromagnetic / mechanical two-way valve.

8. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 7, characterized in that: The electromagnetic ball check valve comprises: The valve seat is a cylindrical structure with a completely through cavity in the middle, and a shrinking chamfer is provided in the cavity; an electromagnet is provided at the lower end of the valve seat; A sphere with a hollow interior, the sphere is placed in the cavity of the valve seat and is provided with a chamfer in the cavity to form a line contact; A guide sleeve is connected to one end of the valve seat close to the sphere, and a lift limiter is arranged inside the guide sleeve to limit the lift of the sphere.

9. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 8, characterized in that: The sphere is an iron ball.

10. The multi-cylinder single-acting reciprocating fertilizer pump according to claim 8, characterized in that: The lower end of the valve seat is provided with a groove, and the electromagnet is placed in the groove.

Images