Electromagnetic pump
By adopting a double-moving iron core structure in the electromagnetic pump, the direction of movement is opposite to offset the change in the center of mass, the problem of large vibration of the electromagnetic pump is solved and more stable operation is achieved.
Patent Information
- Application Number
- CN202410123567.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-29
- Publication Date
- 2025-07-29
AI Technical Summary
The existing electromagnetic pumps produce large vibrations during the movement of the moving iron core, which affects the stability and service life of the equipment.
A double-moving iron core structure is adopted, by setting the first moving iron core and the second moving iron core, the direction of movement is opposite, thereby forming opposite potential energy offsets, reducing the change in the center of mass of the electromagnetic pump as a whole, and reducing the vibration amplitude.
It effectively reduces the vibration of the electromagnetic pump and improves the stability and service life of the equipment.
Smart Images
Figure CN120384871A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of fluid control, and particularly to an electromagnetic pump. Background Art
[0002] The electromagnetic pump includes an electromagnetic driving part and a valve body. A moving iron core and a valve needle connected to the moving iron core are arranged in the valve body. The valve needle is used to open and close a valve port arranged in the valve body and control the opening degree of the valve port.
[0003] During the movement of the moving iron core, the overall electromagnetic pump will generate relatively large vibrations. Reducing such vibrations has always been pursued by those skilled in the art. Summary of the Invention
[0004] An object of the present invention is to provide a new technical solution for an electromagnetic pump, which improves the structure of the electromagnetic pump to reduce the vibration of the electromagnetic pump.
[0005] The present invention provides an electromagnetic pump, including a valve body, a valve seat, and an electromagnetic driving part arranged outside the valve body. The valve body abuts against the valve seat, and the valve body has a valve cavity;
[0006] A first elastic member, a first moving iron core, a second moving iron core, a second elastic member, and an elastic member are arranged in the valve cavity. The electromagnetic pump is provided with a valve port. The second moving iron core is closer to the valve port than the first moving iron core. The first moving iron core is located between the first elastic member and the elastic member. The first elastic member directly or indirectly abuts between the valve body and the first moving iron core. The elastic member directly or indirectly abuts between the first moving iron core and the second moving iron core. One side portion of the second elastic member directly or indirectly abuts against the second moving iron core, and the other side portion directly or indirectly abuts against the valve seat.
[0007] In the electromagnetic pump structure provided by the present application, by arranging two moving iron cores, when the two moving iron cores are driven, two opposite-direction movement trends can be formed and will be partially or almost completely offset. The change in the overall center of mass of the electromagnetic pump is smaller, and the vibration amplitude of the remaining components of the electromagnetic pump will be reduced, thereby reducing the overall vibration of the electromagnetic pump. Brief Description of the Drawings
[0008] The drawings incorporated in the specification and constituting a part of the specification illustrate embodiments of the present specification and, together with the description, are used to explain the principles of the present specification.
[0009] Figure 1 It is a schematic structural diagram of the electromagnetic pump in the present invention, and the electromagnetic pump is in one state;
[0010] Figure 2 It is a schematic structural diagram of the electromagnetic pump in the present invention, and the electromagnetic pump is in another state;
[0011] Figure 3 is Figure 1 a partially enlarged schematic view of;
[0012] Figure 4 is a structural diagram of the first moving iron core;
[0013] Figure 5 is Figure 4 a side sectional view of;
[0014] Figure 6 is a structural diagram of the second moving iron core;
[0015] Figure 7 is Figure 6 a side sectional view of.
[0016] Explanation of reference numerals in the drawings:
[0017] 1. Electromagnetic pump; 20. First elastic member; 170. Electromagnetic drive part; 10. Valve body; 11. First stop surface part; 12. Second stop surface part; 13. Valve seat; 14. Valve body; 15. Valve port; 31. First magnetic conductive ring; 32. Second magnetic conductive ring; 40. First moving iron core; 41. First end surface part; 42. First center line; 43. Third end surface part; 44. Boss part; 45. Fourth center line; 50. Elastic member; 60. Spacer part; 61. First magnetic conductive surface; 62. Third center line; 63. Second magnetic conductive surface; 70. Second moving iron core; 71. Second end surface part; 72. Second center line; 73. Socket part; 74. Body part; 75. Valve needle; 80. Second elastic member; 90. Retaining ring; 110. Piston ball; 120. Support spring. Detailed implementation manners
[0018] In order to enable those skilled in the art of this technology to better understand the solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners.
[0019] As Figure 1 shown, the present application provides an electromagnetic pump 1. As Figure 1 shown, it includes a valve body 10, a valve seat 13, and an electromagnetic drive part 170 arranged outside the valve body 10. The valve body 10 abuts against the valve seat 13, and the valve body 10 has a valve cavity;
[0020] Inside the valve chamber, a first elastic member 20, a first moving iron core 40, a second moving iron core 70, a second elastic member 80, and an elastic member 50 are provided. The electromagnetic pump is provided with a valve port 15. The second moving iron core 70 is closer to the valve port 15 than the first moving iron core 40. The first moving iron core 40 is located between the first elastic member 20 and the elastic member 50. The first elastic member 20 directly or indirectly abuts between the valve body 10 and the first moving iron core 40. The elastic member 50 directly or indirectly abuts between the first moving iron core 40 and the second moving iron core 70. One side portion of the second elastic member 80 abuts against the second moving iron core 70, and the other side portion directly or indirectly abuts against the valve seat 13.
[0021] In the electromagnetic pump structure provided by the present application, by providing two moving iron cores, when the two moving iron cores are driven, two potential movements in opposite directions can be formed, and part or almost all of them will cancel each other out. The change in the center of mass of the overall electromagnetic pump is smaller, and the vibration amplitude of the remaining components of the electromagnetic pump will be reduced, thereby reducing the overall vibration of the electromagnetic pump.
[0022] Specifically, the electromagnetic pump 1 includes a valve body 10 provided with a valve port 15 and an electromagnetic driving portion 170 provided outside the valve body 10. The valve body 10 has a valve chamber. The valve port 15 communicates with the valve chamber. The walls surrounding the valve chamber include a first stop surface portion 11 and a second stop surface portion 12, and the first stop surface portion 11 and the second stop surface portion 12 are arranged oppositely. Inside the valve chamber, a first moving iron core 40, a second moving iron core 70, and an elastic member 50 are provided. The second moving iron core 70 is arranged closer to the valve port than the first moving iron core 40 for regulating the opening degree of the valve port 15. The elastic member 50 is located between the first moving iron core 40 and the second moving iron core 70 and is in linkage cooperation with the first moving iron core 40 and the second moving iron core 70. Among them, the first stop surface portion 11 and the second stop surface portion 12 are parts that can form stops for the first moving iron core 40 and the second moving iron core 70.
[0023] In this embodiment, the elastic member 50 is a helical spring. The two ends of the elastic member 50 are welded, clamped, or adhered to the first moving iron core 40 and the second moving iron core 70. It can be the first moving iron core 40 that is used to open, close the valve port 15, and regulate the opening degree of the valve port 15, or it can be the second moving iron core 70 that is used to open, close the valve port 15, and regulate the opening degree of the valve port 15. The first and second do not serve as limitations on the positions, functions, and types of the iron cores.
[0024] If only a single moving iron core is provided inside the valve body 10, during the movement of the single moving iron core, according to the theorem of the motion of the center of mass in theoretical mechanics, other components except the single moving iron core in the moving state will form reverse vibrations relative to the single moving iron core to keep the overall center of mass position of the electromagnetic pump 1 unchanged. Since the various components of the electromagnetic pump 1 are not rigidly matched, relatively large vibrations will be formed.
[0025] In the embodiments of the present application, by providing two moving iron cores, namely the first moving iron core 40 and the second moving iron core 70, when the electromagnetic driving part 170 is energized, the first moving iron core 40 and the second moving iron core 70 move towards each other, that is, the moving directions of the first moving iron core 40 and the second moving iron core 70 are opposite. When the first moving iron core 40 moves downward, according to the theorem of the motion of the center of mass, the rest of the components of the electromagnetic pump 1 will generate a tendency to move upward. Under the action of the second moving iron core 70 moving upward at the same time, the rest of the components of the electromagnetic pump 1 will generate a tendency to move downward at the same time. In this way, the two opposite-direction moving tendencies will be partially or completely cancelled out, the change in the center of mass of the overall electromagnetic pump 1 will be smaller, and the vibration amplitude of the rest of the components of the electromagnetic pump 1 will be reduced, thereby reducing the overall vibration of the electromagnetic pump 1.
[0026] Specifically, in this embodiment, the first moving iron core 40 and the second moving iron core 70 can move along the axial direction of the valve cavity, that is, Figure 1 the Y direction in Figure 1 . In
[0027] As Figure 2 shown, when the electromagnetic driving part 170 is powered off, the elastic member 50 returns to its deformed state to drive the first moving iron core 40 and the second moving iron core 70 to move away from each other, and the second moving iron core 70 can move close to and seal the valve port 15.
[0028] The first moving iron core 40 is fitted to the first stop surface portion 11, and the second moving iron core 70 is fitted to the second stop surface portion 12. That is, the elastic member 50 returns to its deformed state to push the first moving iron core 40 to move axially upward until it is stopped in cooperation with the first stop surface portion 11. The elastic member 50 simultaneously pushes the second moving iron core 70 to move radially downward until it is stopped in cooperation with the second stop surface portion 12, and at this time the valve port 15 is closed.
[0029] In addition, by adopting the method in the present application, when the electromagnetic driving part 170 is powered off, the elastic member 50 located between the first moving iron core 40 and the second moving iron core 70 drives the first moving iron core 40 and the second moving iron core 70 to reset. Since the restoring force of the elastic member 50 is released through the first moving iron core 40 and the second moving iron core 70 instead of directly applying the restoring force to the valve body 10, the vibration of the electromagnetic pump 1 can also be reduced.
[0030] In some other embodiments of the electromagnetic pump 1, the radial direction is Figure 1 the X direction in
[0031] Referring to Figure 1 , Figure 2 and Figure 3 , the electromagnetic driving part 170 includes a first magnetic conduction ring 31 and a second magnetic conduction ring 32, and the first magnetic conduction ring 31 and the second magnetic conduction ring 32 are arranged along the axial direction. The first magnetic conduction ring 31 has a first magnetic conduction surface 61, the second magnetic conduction ring 32 has a second magnetic conduction surface 63, and the first magnetic conduction surface 61 and the second magnetic conduction surface 63 are arranged opposite to each other axially. There is a spacing part 60 between the first magnetic conduction surface 61 and the second magnetic conduction surface 63, and the spacing part 60 is used to block the linear magnetic path between the first magnetic conduction ring 31 and the second magnetic conduction ring 32. Wherein, the first magnetic conduction ring 31 and the second magnetic conduction ring 32 are made of soft magnetic materials with low remanence,
[0032] Wherein, the spacing part 60 is an annular cavity. Or the spacing part 60 is a spacing ring, and the spacing ring is made of non-ferromagnetic material.
[0033] Specifically, the electromagnetic driving part 170 includes a housing, and the first magnetic conduction ring 31 and the second magnetic conduction ring 32 are arranged inside the housing. When the spacing part 60 is a cavity, the first magnetic conduction ring 31 and the second magnetic conduction ring 32 are clamped or welded inside the housing. The wall forming the cavity includes the first magnetic conduction surface 61 and the second magnetic conduction surface 63.
[0034] When the spacing part 60 is a spacing ring, the first magnetic conduction ring 31, the spacing ring and the second magnetic conduction ring 32 are stacked in sequence inside the housing.
[0035] In this embodiment, the first moving iron core 40 has a first center line 42 passing through its center of gravity, the second moving iron core 70 has a second center line 72 passing through its center of gravity, the spacing part has a third center line 62 passing through its center of gravity, and the first center line 42, the second center line 72 and the third center line 62 are parallel to each other and extend along the radial direction.
[0036] Wherein, as shown in Fig. 3 and Figure 5 shown, the first center line 42 refers to the line passing through the center of gravity of the first moving iron core 40 in the radial direction. The second center line 72 refers to the line passing through the center of gravity of the first moving iron core 70 in the radial direction. The third center line refers to the line passing through the midpoint of the first magnetic conduction surface 61 and the second magnetic conduction surface 63 in the radial direction.
[0037] In order to ensure that the first moving iron core 40 and the second moving iron core 70 move in opposite directions under the action of magnetic force all the time. Axially, the first center line 42 always remains on one side of the third center line 62, and the second center line 72 always remains on the other side of the third center line 62.
[0038] Specifically, one end of the elastic member 50 abuts against the first moving iron core 40 so that the first center line 42 is always on one side of the third center line 62; the other end abuts against the second moving iron core 70 so that the second center line 72 is always on the other side of the third center line 62.
[0039] By providing the spacer portion 60, the straight magnetic path between the first magnetic conduction ring 31 and the second magnetic conduction ring 32 can be blocked, so that the magnetic path returns to the first magnetic conduction ring 31 after passing through the second moving iron core 70 and the first moving iron core 40 in sequence through the second magnetic conduction ring 32. Thus, the electromagnetic driving portion 170 can form a closed-loop magnetic line of force, the magnetic line of force is parallel to the axial direction, and the third center line 62 passes through the center of the closed-loop magnetic line of force in the radial direction. After the electromagnetic driving portion 170 is powered on, according to the principle that the direction of the force on the ferromagnetic material in the magnetic field is the direction to make the magnetic path of the magnetic field the shortest, the directions of the forces on the first moving iron core 40 and the second moving iron core 70 are always towards the direction of the third center line 62 of the spacer portion 60.
[0040] The first moving iron core 40 moves downward under the downward magnetic force, and the second moving iron core 70 moves upward under the upward magnetic force. Until the elastic force of the elastic driving portion 170 is close to the electromagnetic force, the first moving iron core 40 and the second moving iron core 70 stop moving. At this time, the elastic driving portion 170 abuts between the first moving iron core 40 and the second moving iron core 70. At this time, axially, the first center line 42 and the second center line 72 are still disposed on both sides of the third center line 62.
[0041] In a specific example, when the difference between the maximum elastic force of the elastic member 50 and the electromagnetic forces received by the two moving iron cores is greater than or equal to 2N, the first moving iron core 40 and the second moving iron core 70 stop moving. It can be understood that this value is only a specific embodiment and does not constitute a limitation to the present application.
[0042] Optionally, in an example, the first moving iron core 40 includes a first end face 41, and the second moving iron core 70 includes a second end face 71. Axially, the first end face 41 and the second end face 71 are fitted to both ends of the elastic member 50. That is, the first end face 41 and the second end face 71 maintain a state of abutting against both ends of the elastic member 50.
[0043] The first end face 41 and the first magnetic conduction surface 61 are in the same plane, and the second end face 71 and the second magnetic conduction surface 63 are in the same plane. That is to say, being in the same plane means that the plane where the first end face 41 is located is substantially coincident with the plane where the first magnetic conduction surface 61 is located, and the plane where the second end face 71 is located is substantially coincident with the plane where the second magnetic conduction surface 63 is located. Thus, it can be ensured that the moving distances of the first moving iron core 40 and the second moving iron core 70 and the magnitudes of the magnetic forces received are appropriate.
[0044] If the distance between the first end face portion 41 and the side of the first magnetic conduction face 61 away from the second magnetic conduction face 63 is too large, the magnetic force on the first moving iron core 40 will rapidly decrease. If the plane where the first end face portion 41 is located is between the planes where the first magnetic conduction face 61 and the second magnetic conduction face 63 are located, the moving distance of the first moving iron core 40 will be shortened.
[0045] In another example, that is Figure 1 As shown, one of the first end face portion 41 and the second end face portion 71 is provided with a boss portion 44 protruding in the direction close to the elastic member 50, and the other is provided with a socket portion 73 into which the boss portion 44 can be inserted.
[0046] However, in the previous embodiment, the first end face portion 41 and the second end face portion 71 are nearly flat, without a boss portion, or with a slight protrusion.
[0047] In this embodiment, the boss portion 44 is located on the first end face portion 41. The first end face portion 41 is on the side of the first magnetic conduction face 61 away from the second magnetic conduction face 63, and forms a first distance from the first magnetic conduction face 61. The second end face portion 71 and the second magnetic conduction face 63 are in the same plane.
[0048] Alternatively, the boss portion 44 is located on the second end face portion 71. The second end face portion 71 is on the side of the second magnetic conduction face 63 away from the first magnetic conduction face 61, and forms a second distance from the second magnetic conduction face 63. The first end face and the first magnetic conduction face 61 are in the same plane.
[0049] By providing the boss portion 44 on the first moving iron core 40 or the second moving iron core 70, the length of its movement stroke can be increased, and at the same time, the overall length dimension of the electromagnetic pump 1 can be prevented from increasing. At the same time, the length of the iron core under the action of electromagnetic force can be extended, and the electromagnetic force can be increased.
[0050] Optionally, there is a third distance between the first magnetic conduction face 61 and the second magnetic conduction face 63, and the ratio of the first distance to the third distance is between 0.5 and 1; or the ratio of the second distance to the third distance is between 0.5 and 1.
[0051] For example, the third distance is between 8 cm and 14 cm. The boss portion 44 is located on the first end face portion 41, and the first distance is between 4 cm and 7 cm. Or the boss portion 44 is located on the second end face portion 71, and the second distance is between 4 cm and 7 cm. Within this range, the force range of the iron core provided with the boss portion 44 is large, the magnetic force action is strong, and at the same time, the moving stroke length of the moving iron core provided with the boss portion 44 can be increased.
[0052] Optionally, as Figure 3 、 Figure 4 and Figure 5As shown, the boss portion 44 is conical. The boss portion 44 has a fourth median line 45, and the fourth median line 45 extends perpendicular to the axial direction. Taking the case where the boss portion 44 is provided on the first end face portion 41 as an example, the fourth median line refers to the line that, in the radial direction, passes through the midpoint of the top table face of the boss portion 44 and the first end face portion.
[0053] The boss portion 44 is located on the first end face portion 41, and the fourth median line 45 is located in the plane where the first magnetic conduction face 61 is located. The boss portion 44 is located on the second end face portion 71, and the fourth median line 45 is located in the plane where the second magnetic conduction face 63 is located. Thus, the magnetic force and the length of the stroke of the moving iron core provided with the boss portion 44 can be further optimized.
[0054] Furthermore, the cone has a slope face portion, and the slope face portion is provided between the table face of the boss portion 44 and the first end face portion 41, or the slope face portion is provided between the table face and the second end face portion 71. The inclination angle of the slope face portion is 20° - 40°. Within this range, the moving iron core provided with the boss portion 44 is subjected to the greatest force.
[0055] In the above embodiment, as Figure 1 and Figure 2 shown, a first elastic member 20 and a second elastic member 80 are further provided in the valve cavity. The first elastic member 20 is directly or indirectly supported between the first moving iron core 40 and the first stop face portion 11, and the second elastic member 80 is directly or indirectly supported between the second moving iron core 70 and the first stop face portion 11.
[0056] The first elastic member 20 and the second elastic member 80 are shock pads, and the shock pads are elastic materials such as rubber. The first elastic member 20 and the second elastic member 80 are springs. When the first elastic member 20 and the second elastic member 80 are springs, it is possible to prevent the first moving iron core 40 and the second moving iron core 70 from contacting the first stop face portion 11 and the second stop face portion 12, thereby better reducing the vibration of the electromagnetic pump 1.
[0057] Optionally, as Figure 3 shown, when the first elastic member 20 is a spring, a third end face portion 43 is provided at the end of the first moving iron core 40 away from the first end face portion 41, and at least a part of the third end face portion 43 is inserted into the first elastic member 20 to form a limit for the first elastic member 20 in the radial direction.
[0058] Optionally, at least a part of the first end face portion 41 and the second end face portion 71 extends into both ends of the elastic member 50 to form a limit for the elastic member 50 in the radial direction. When the boss portion 44 is provided on the first end face portion 41 and the second end face portion 71, the boss portion 44 is inserted into the elastic member 50.
[0059] In a specific embodiment, refer to Figure 1 、 Figure 2 and Figure 7, the valve body 10 includes a valve body 14 and a valve seat 13, and a valve port 15 is formed in the valve seat 13. A piston ball 110 and a support spring 120 are also provided at the valve port 15.
[0060] The second moving iron core 70 is used to open and close the valve port 15 and adjust the opening degree of the valve port 15. The second moving iron core 70 has a body portion 74 and a valve needle 75. The second end face portion 71 is located on the body portion 74, and a second elastic member 80 is provided between the second stop face portion 12 and the second end face portion 71. The valve needle 75 is located on the side of the body portion 74 opposite to the second end face portion 71. The body portion 74 is located inside the valve body 14 and is adapted to the inner diameter dimension of the valve body 14. The valve needle 75 passes through the second elastic member 80 and cooperates with the piston.
[0061] Optionally, a retaining ring 90 is further provided inside the valve body 14. When the retaining ring 90 is provided, the second stop face portion 12 is located on the retaining ring 90, and one end of the second elastic member 80 abuts against the retaining ring 90. The valve needle 75 passes through the retaining ring 90, and the retaining ring 90 contacts the outer wall of the valve needle 75. The valve needle 75 can move axially up and down relative to the retaining ring 90.
[0062] By driving the second moving iron core 70 to move axially up and down through the electromagnetic driving portion 170, the valve needle 75 can press the piston ball 110 to close the valve port 15 or move away from the piston ball 110 to open the valve port 15.
[0063] In this article, specific examples are used to elaborate on the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be pointed out that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.
Claims
1. An electromagnetic pump, characterized in that, It includes a valve body (10), a valve seat (13), and an electromagnetic driving part (170) arranged outside the valve body (10). The valve body (10) abuts against the valve seat (13), and the valve body (10) has a valve cavity; A first elastic member (20), a first moving iron core (40), a second moving iron core (70), a second elastic member (80), and an elastic member (50) are arranged in the valve cavity. The electromagnetic pump is provided with a valve port (15). The second moving iron core (70) is closer to the valve port (15) than the first moving iron core (40). The first moving iron core (40) is located between the first elastic member (20) and the elastic member (50). The first elastic member (20) directly or indirectly abuts between the valve body (10) and the first moving iron core (40). The elastic member (50) directly or indirectly abuts between the first moving iron core (40) and the second moving iron core (70). One side of the second elastic member (80) abuts against the second moving iron core (70), and the other side directly or indirectly abuts against the valve seat (13).
2. The electromagnetic pump according to claim 1, characterized in that, A first elastic member (20) and a second elastic member (80) are also arranged in the valve cavity. The first elastic member (20) directly or indirectly axially supports between the first moving iron core (40) and the valve body (10). The second elastic member (80) axially directly or indirectly supports between the second moving iron core (70) and the valve body (10); The electromagnetic driving part (170) is energized to drive the first moving iron core (40) and the second moving iron core (70) to move towards each other. The second moving iron core (70) can move away from and open the valve port (15). The elastic member (50) deforms under the action of the first moving iron core (40) and the second moving iron core (70) to store energy; When the electromagnetic driving part (170) is in a power-off state, the elastic member (50) recovers its deformation, driving the first moving iron core (40) and the second moving iron core (70) to move away from each other. The second moving iron core (70) can move closer to and seal the valve port (15).
3. The electromagnetic pump according to claim 1, characterized in that, The first elastic member (20) and the second elastic member (80) are springs; or the first elastic member (20) and the second elastic member (80) are shock pads.
4. The electromagnetic pump according to any one of claims 1 to 3, characterized in that, The electromagnetic driving part (170) includes a first magnetic conductive ring (31) and a second magnetic conductive ring (32). The first magnetic conductive ring (31) and the second magnetic conductive ring (32) are arranged axially. There is a spacer (60) between the first magnetic conductive ring (31) and the second magnetic conductive ring (32). The spacer (60) is used to block the linear magnetic path between the first magnetic conductive ring (31) and the second magnetic conductive ring (32); The first movable iron core (40) has a first median line (42) passing through its center of gravity, the second movable iron core (70) has a second median line (72) passing through its center of gravity, and the spacer has a third median line (62) passing through its center of gravity. The first median line (42), the second median line (72), and the third median line (62) are parallel to each other and extend radially; Axially, the first median line (42) is always on one side of the third median line (62), and the second median line (72) is always on the other side of the third median line (62).
5. The electromagnetic pump according to claim 4, characterized in that, One end of the elastic member (50) abuts against the first movable iron core (40) so that the first median line (42) is always on one side of the third median line (62); The other end abuts against the second movable iron core (70) so that the second median line (72) is always on the other side of the third median line (62).
6. The electromagnetic pump according to claim 4, wherein The spacer (60) is an annular cavity, or the spacer (60) is a spacer ring made of non-ferromagnetic material.
7. The electromagnetic pump according to claim 6, characterized in that, The first magnetic conduction ring (31) has a first magnetic conduction surface (61), the second magnetic conduction ring (32) has a second magnetic conduction surface (63), the first magnetic conduction surface (61) and the second magnetic conduction surface (63) are axially opposite to each other, and the third median line (62) passes through the midpoint of the first magnetic conduction surface (61) and the second magnetic conduction surface (63) axially.
8. The electromagnetic pump according to claim 7, characterized in that, The first movable iron core (40) includes a first end face (41), the second movable iron core (70) includes a second end face (71), and axially, the first end face (41) and the second end face (71) are fitted to both ends of the elastic member (50); The first end face (41) and the first magnetic conduction surface (61) are in the same plane, and the second end face (71) and the second magnetic conduction surface (63) are in the same plane.
9. The electromagnetic pump according to claim 7, wherein The first movable iron core (40) includes a first end face (41), and the second movable iron core (70) includes a second end face (71); One of the first end face (41) and the second end face (71) is provided with a boss portion (44) that protrudes toward the elastic member (50) and is inserted into one end of the elastic member (50), and the other is provided with a socket portion (73) into which the boss portion (44) can be inserted; The boss portion (44) is located on the first end face (41), the first end face (41) is on the side of the first magnetic conduction surface (61) away from the second magnetic conduction surface (63), and a first distance is formed between the first end face (41) and the first magnetic conduction surface (61). The second end face (71) and the second magnetic conduction surface (63) are in the same plane; or, The boss portion (44) is located on the second end face (71), the second end face (71) is on the side of the second magnetic conduction surface (63) away from the first magnetic conduction surface (61), and a second distance is formed between the second end face (71) and the second magnetic conduction surface (63). The first end face and the first magnetic conduction surface (61) are in the same plane.
10. The electromagnetic pump according to claim 9, wherein, There is a third spacing between the first magnetic conductive surface (61) and the second magnetic conductive surface (63); The ratio of the first spacing to the third spacing is between 0.5 and 1; or, The ratio of the second spacing to the third spacing is between 0.5 and 1.
11. The electromagnetic pump according to claim 9, characterized in that, The boss portion (44) is conical, and the boss portion (44) has a fourth median line (45), and the fourth median line (45) passes through the center of gravity of the boss portion (44) along the radial direction; The boss portion (44) is located on the first end face portion (41), and the fourth median line (45) is located in the plane where the first magnetic conductive surface (61) is located; or, The boss portion (44) is located on the second end face portion (71), and the fourth median line (45) is located in the plane where the second magnetic conductive surface (63) is located.