A high-precision electromagnetic plunger metering pump

Abstract

The present invention discloses a high-precision electromagnetic plunger metering pump, which comprises a pump body, a valve body, an electromagnetic control device and a plunger assembly; the electromagnetic control device comprises a movable armature and an electromagnet assembly for controlling the movement of the armature; the plunger assembly comprises a positioning ring, a buffer heat-insulating ring and a plunger rod. The positioning ring is provided with a receiving groove and a through hole. A first rotation-limiting structure is arranged between the positioning ring and the pump body. The buffer heat-insulating ring is arranged in the receiving groove and connected to the armature. A second rotation-limiting structure is arranged between the buffer heat-insulating ring and the positioning ring. The plunger rod passes through the through hole and extends into the plunger moving groove. A sealing assembly is arranged between the outer periphery of the plunger rod and the plunger moving groove. The arrangement of the buffer heat-insulating ring can, on the one hand, prevent the heat of the armature from being transferred to the plunger rod, limit the relative rotation of the positioning ring with respect to the pump body, and limit the relative rotation of the buffer heat-insulating ring with respect to the positioning ring, so as to ensure that the plunger rod hits the same position in the plunger moving groove each time, making the metering more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic metering pumps, and in particular to a high-precision electromagnetic plunger metering pump. Background Art

[0002] A metering pump is a metering pump with a constant output flow under the condition of a constant rotational speed. Simply put, after the rotational speed of the metering pump is selected, its flow rate cannot be adjusted. Taking the electromagnetic metering pump as an example, it currently mainly has two forms: a rubber diaphragm type and a ceramic plunger type. For the rubber diaphragm type: there are defects such as low metering accuracy, easy aging and rupture of the diaphragm, and poor reliability. Its structure cannot meet the high-precision metering requirements. For the ceramic plunger type: the metering accuracy is higher than that of the rubber diaphragm type. However, in the existing ceramic plunger type metering pump, the ceramic plunger is connected to the moving iron core. The fixed iron core will generate heat during operation, which is then transmitted to the moving iron core and then to the ceramic plunger, easily affecting the reagent flowing into the metering pump. And affected by processing errors (such as flatness), the ceramic plunger is prone to yaw rotation in the pump body, resulting in the ceramic plunger not being able to ensure that each strike is at the same position in the pump body, causing a deviation in the repeat accuracy in the metering calibration process before leaving the factory, affecting the installation and production personnel's judgment of the correct value of the metering pump.

[0003] Therefore, it is necessary to design a new technical solution to solve the above problems. Summary of the Invention

[0004] In view of this, in view of the deficiencies existing in the prior art, the main purpose of the present invention is to provide a high-precision electromagnetic plunger metering pump. The moving iron core is connected to the plunger rod through a buffer heat insulation ring. The setting of the buffer heat insulation ring can, on the one hand, prevent the heat of the moving iron core from being transmitted to the plunger rod, and on the other hand, avoid the plunger rod from hitting the pump body too quickly. And a first rotation limiting structure is provided between the positioning ring and the pump body to limit the relative rotation of the positioning ring with respect to the pump body. A second rotation limiting structure is provided between the buffer heat insulation ring and the positioning ring to limit the relative rotation of the buffer heat insulation ring with respect to the positioning ring, which can ensure that the plunger rod strikes at the same position in the plunger moving groove each time, making the metering more accurate. At the same time, the processing requirement for the flatness of the metering pump can be reduced, thereby reducing the production cost.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-precision electromagnetic plunger metering pump, comprising:

[0007] A pump body, the pump body is provided with a first installation groove and a suction and discharge port, the pump body is provided with a metering channel communicating with the suction and discharge port, the end of the metering channel far from the suction and discharge port is communicated with the first installation groove through a plunger moving groove, and the pump body is further provided with a first liquid inlet channel and a first liquid outlet channel;

[0008] Valve body, the valve body is provided with a main channel, a second liquid inlet channel and a second liquid outlet channel that can communicate with the main channel. The main channel communicates with the suction and discharge ports. The second liquid inlet channel communicates with the first liquid inlet channel. The second liquid outlet channel communicates with the first liquid outlet channel;

[0009] Electromagnetic control device, the electromagnetic control device includes a movable iron core and an electromagnet assembly for controlling the movement of the iron core;

[0010] Plunger assembly, the plunger assembly includes a positioning ring, a buffer heat insulation ring and a plunger rod. The positioning ring is arranged in the first installation groove. The positioning ring is provided with a receiving groove and a through hole for the plunger rod to pass through and communicate with the receiving groove. A first rotation limiting structure is arranged between the positioning ring and the pump body. The first rotation limiting structure is used to prevent the positioning ring from rotating relative to the pump body. The electromagnetic control device fixes the positioning ring in the first installation groove. The buffer heat insulation ring is arranged in the receiving groove and connected to the iron core. A second rotation limiting structure is arranged between the buffer heat insulation ring and the positioning ring. One end of the buffer heat insulation ring away from the iron core is provided with a second installation groove. The plunger rod is arranged in the second installation groove. One end of the plunger rod away from the buffer heat insulation ring passes through the through hole and extends into the plunger moving groove. A sealing assembly is arranged between the outer periphery of the plunger rod and the plunger moving groove. The electromagnet assembly drives the plunger rod to move in the plunger moving groove through the iron core.

[0011] As a preferred solution, the first rotation limiting structure includes a positioning pin and a positioning hole. The positioning hole is formed together on the outer periphery of the positioning ring and the wall surface of the first installation groove. The positioning pin is inserted into the positioning hole.

[0012] As a preferred solution, the second rotation limiting structure includes a first rotation limiting surface and a second rotation limiting surface. There are two opposite or adjacent first rotation limiting surfaces. The two first rotation limiting surfaces are arranged on the outer periphery of the buffer heat insulation ring. There are two second rotation limiting surfaces. The two second rotation limiting surfaces are arranged on the wall surface of the receiving groove and are arranged corresponding to the first rotation limiting surface. Avoidance grooves for preventing interference between the first rotation limiting surface and the second rotation limiting surface are arranged on both sides of the wall surface of the receiving groove at the second rotation limiting surface.

[0013] As a preferred solution, a convex column protrudes from one end of the iron core away from the electromagnet assembly. Correspondingly, a concave position matching the convex column is recessed at one end of the buffer heat insulation ring close to the iron core. The concave position is clamped on the convex column. A positioning groove is arranged on the outer periphery of the convex column of the iron core. Correspondingly, the buffer heat insulation ring is provided with a positioning convex portion matching the positioning groove. The positioning convex portion is clamped in the positioning groove.

[0014] As a preferred solution, one end of the buffer heat insulation ring close to the iron core is fixed to one end of the iron core away from the electromagnet assembly by structural adhesive.

[0015] As a preferred solution, the sealing assembly includes an O-ring and a sealing ring. The sealing ring has a through-hole, and a first annular extension portion and a second annular extension portion are respectively extended at both ends of the through-hole of the sealing ring. A three-stage stepped groove is formed on the wall surface of the plunger moving groove. The positioning ring and the plunger rod together fix the sealing ring to a section of the three-stage stepped groove close to the positioning ring. The plunger rod fixes the first annular extension portion to a section of the three-stage stepped groove far from the positioning ring. The sealing ring and the first annular extension portion fix the O-ring to the middle section of the three-stage stepped groove. The plunger rod fixes the second annular extension portion to the through-hole.

[0016] As a preferred solution, a valve body installation portion extends beside the pump body. The valve body is fixed on the valve body installation portion. The metering channel includes a horizontal section and a first vertical section and a second vertical section connected to the horizontal section. The horizontal section penetrates the valve body installation portion. The valve body installation portion is provided with a plug for blocking the end of the horizontal section. The suction and discharge port is arranged at one end of the first vertical section far from the horizontal section. The plunger moving groove is arranged at one end of the second vertical section far from the horizontal section.

[0017] As a preferred solution, the valve body is a three-way valve.

[0018] As a preferred solution, the electromagnet assembly includes a pressure plate, a skeleton, a fixed iron core, a coil, and an iron shell. The pressure plate is fixed on the pump body and is used to fix the positioning ring in the first installation groove. The iron shell is fixed on the pressure plate and fixes the skeleton in the iron shell. The skeleton includes an inner cavity and an outer cavity separated from the inner cavity. The moving iron core is movably arranged at one end of the inner cavity close to the pump body. The fixed iron core is arranged at one end of the inner cavity far from the pump body. An elastic member for driving the moving iron core to move towards the pump body is clamped between the fixed iron core and the moving iron core. The coil is arranged in the outer cavity.

[0019] As a preferred solution, the electromagnet assembly further includes an adjusting nut. One end of the fixed iron core far from the moving iron core extends out of the iron shell and is provided with a threaded portion. The adjusting nut is connected to the threaded portion and is used to adjust the position of the fixed iron core in the inner cavity.

[0020] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical solutions that:

[0021] Specifically, the moving iron core is connected to the plunger rod through a buffer heat insulation ring. The buffer heat insulation ring can prevent the heat of the moving iron core from being transferred to the plunger rod on the one hand, and avoid the plunger rod hitting the pump body too quickly on the other hand. A first rotation limiting structure is provided between the positioning ring and the pump body to limit the rotation of the positioning ring relative to the pump body. A second rotation limiting structure is provided between the buffer heat insulation ring and the positioning ring to limit the rotation of the buffer heat insulation ring relative to the positioning ring, which can ensure that the plunger rod hits the same position of the plunger moving groove each time, making the metering more accurate. At the same time, the requirement for the flatness machining of the metering pump can be reduced, and thus the production cost can be reduced.

[0022] To more clearly illustrate the structural features and functions of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a perspective schematic diagram of a preferred embodiment of the present invention;

[0024] Figure 2 is an exploded schematic diagram of a preferred embodiment of the present invention;

[0025] Figure 3 is a cross-sectional schematic diagram of a preferred embodiment of the present invention;

[0026] Figure 4 is Figure 3 a partial enlarged view of part A in

[0027] Figure 5 is another cross-sectional schematic diagram of a preferred embodiment of the present invention;

[0028] Figure 6 is an assembly schematic diagram of the plunger assembly of a preferred embodiment of the present invention.

[0029] DESCRIPTION OF THE REFERENCE NUMERALS IN THE DRAWINGS:

[0030] 10. Pump body 11. Valve body installation part

[0031] 12. Plug 101. First installation groove

[0032] 102. Suction and discharge port 103. Metering channel

[0033] 1031. Horizontal section 1032. First vertical section

[0034] 1033. Second vertical section 104. Plunger moving groove

[0035] 105. First liquid inlet channel 106. First liquid outlet channel

[0036] 107. Three-stage stepped groove 20. Valve body

[0037] 201, Main channel 202, Second liquid inlet channel

[0038] 203, Second liquid outlet channel 30, Electromagnetic control device

[0039] 31, Moving iron core 311, Convex column

[0040] 312, Positioning groove 32, Electromagnet assembly

[0041] 321, Pressure plate 322, Skeleton

[0042] 323, Fixed iron core 324, Coil

[0043] 325, Iron shell 326, Inner cavity

[0044] 327, Outer cavity 328, Elastic member

[0045] 329, Threaded portion 40, Plunger assembly

[0046] 41, Positioning ring 411, Accommodating groove

[0047] 412, Through hole 42, Buffer heat insulation ring

[0048] 421, Second installation groove 422, Concave position

[0049] 423, Positioning convex portion 424, Insertion hole

[0050] 425, First glue injection hole 426, Second glue injection hole

[0051] 43, Plunger rod 431, Annular groove

[0052] 50, First rotation limiting structure 51, Positioning pin

[0053] 52, Positioning hole 60, Second rotation limiting structure

[0054] 61, First rotation limiting surface 62, Second rotation limiting surface

[0055] 70, Sealing assembly 71, O-ring

[0056] 72, Sealing ring 721, Through hole

[0057] 722, First annular extension 723, Second annular extension

[0058] 80, Adjusting nut 90, Clearance groove

[0059] 100, Pump housing. Detailed implementation method

[0060] First of all, it should be noted that in the description of the present invention, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0061] Please refer to Figures 1 to 6 As shown, it shows the specific structure of the preferred embodiment of the present invention, including a pump body 10, a valve body 20, an electromagnetic control device 30 and a plunger assembly 40.

[0062] The pump body 10 is provided with a first installation groove 101 and a suction and discharge port 102. The pump body 10 is provided with a metering channel 103 communicating with the suction and discharge port 102. One end of the metering channel 103 far from the suction and discharge port 102 communicates with the first installation groove 101 through a plunger moving groove 104. The pump body 10 is also provided with a first liquid inlet channel 105 and a first liquid outlet channel 106;

[0063] Refer to Figure 2 、 Figure 3 and Figure 5 As shown, specifically, a valve body installation part 11 extends beside the pump body 10. The metering channel 103 includes a horizontal section 1031 and a first vertical section 1032 and a second vertical section 1033 connected to the horizontal section 1031. The horizontal section 1031 penetrates through the valve body installation part 11. The arrangement of the horizontal section 1031 penetrating through the valve body installation part 11 facilitates the processing and manufacturing of the horizontal section 1031. The valve body installation part 11 is provided with a plug 12 for blocking the end of the horizontal section 1031. The suction and discharge port 102 is arranged at one end of the first vertical section 1032 far from the horizontal section 1031. The first liquid inlet channel 105 and the first liquid outlet channel 106 are respectively arranged on both sides of the first vertical section 1032. The plunger moving groove 104 is arranged at one end of the second vertical section 1033 far from the horizontal section 1031.

[0064] The valve body 20 is provided with a main channel 201 and a second liquid inlet channel 202 and a second liquid outlet channel 203 that can communicate with the main channel 201. The main channel 201 communicates with the suction and discharge port 102. The second liquid inlet channel 202 communicates with the first liquid inlet channel 105. The second liquid outlet channel 203 communicates with the first liquid outlet channel 106;

[0065] Refer to Figure 2 and Figure 5As shown, specifically, the valve body 20 is fixed to the bottom of the valve body mounting portion 11, and the valve body 20 is parallel to the pump main body 10; in this embodiment, the valve body 20 is a three-way valve, and the second liquid inlet channel 202 and the second liquid outlet channel 203 are respectively arranged on both sides of the main channel 201, which can be used for the switching of liquid suction and discharge to achieve quantitative metering.

[0066] The electromagnetic control device 30 includes a movable armature 31 and an electromagnet assembly 32 for controlling the movement of the armature 31; the plunger assembly 40 includes a positioning ring 41, a buffer heat insulation ring 42, and a plunger rod 43. The positioning ring 41 is arranged in the first installation groove 101. The positioning ring 41 is provided with a receiving groove 411 and a through hole 412 communicating with the receiving groove 411 for the plunger rod 43 to pass through. A first rotation limiting structure 50 is arranged between the positioning ring 41 and the pump main body 10, and the first rotation limiting structure 50 is used to prevent the positioning ring 41 from rotating relative to the pump main body 10. The electromagnetic control device 30 fixes the positioning ring 41 in the first installation groove 101. The buffer heat insulation ring 42 is arranged in the receiving groove 411 and connected to the armature 31. The buffer heat insulation ring 42 can be made of rubber. A second rotation limiting structure 60 is arranged between the buffer heat insulation ring 42 and the positioning ring 41. One end of the buffer heat insulation ring 42 away from the armature 31 is provided with a second installation groove 421. The plunger rod 43 is arranged in the second installation groove 421. The plunger rod 43 can be a ceramic plunger rod 43. One end of the plunger rod 43 away from the buffer heat insulation ring 42 passes through the through hole 412 and extends into the plunger moving groove 104. A sealing assembly 70 is arranged between the outer periphery of the plunger rod 43 and the plunger moving groove 104. The electromagnet assembly 32 drives the plunger rod 43 to move in the plunger moving groove 104 through the armature 31;

[0067] Refer to Figure 3 As shown, specifically, the electromagnet assembly 32 includes a pressure plate 321, a skeleton 322, a fixed iron core 323, a coil 324, and an iron shell 325. The pressure plate 321 is fixed to the pump main body 10 and is used to fix the positioning ring 41 in the first installation groove 101. The iron shell 325 is fixed to the pressure plate 321 and fixes the skeleton 322 in the iron shell 325. The skeleton 322 includes an inner cavity 326 and an outer cavity 327 separated from the inner cavity 326. The armature 31 is movably arranged at one end of the inner cavity 326 close to the pump main body 10. The fixed iron core 323 is arranged at one end of the inner cavity 326 away from the pump main body 10. An elastic member 328 for driving the armature 31 to move towards the pump main body 10 is clamped between the fixed iron core 323 and the armature 31. The elastic member 328 can be a spring. The coil 324 is arranged in the outer cavity 327;

[0068] Preferably, the electromagnet assembly 32 further includes an adjusting nut 80. One end of the fixed iron core 323 away from the moving iron core 31 extends out of the iron shell 325 and is provided with a threaded portion 329. The adjusting nut 80 is connected to the threaded portion 329 and is used to adjust the position of the fixed iron core 323 in the inner cavity 326, so as to adjust the suction displacement. The iron shell 325 is covered with a pump housing 100, and the adjusting nut 80 is exposed at the bottom of the pump housing 100.

[0069] Refer to Figure 2 and Figure 6 As shown, the first rotation limiting structure 50 includes a positioning pin 51 and a positioning hole 52. The positioning hole 52 is formed in the outer periphery of the positioning ring 41 and the wall surface of the first installation groove 101 together, and the positioning pin 51 is inserted into the positioning hole 52.

[0070] The second rotation limiting structure 60 includes a first rotation limiting surface 61 and a second rotation limiting surface 62. There are two first rotation limiting surfaces 61 arranged opposite or adjacent to each other. The two first rotation limiting surfaces 61 are arranged on the outer periphery of the buffer heat insulation ring 42. There are two second rotation limiting surfaces 62. The two second rotation limiting surfaces 62 are arranged on the wall surface of the accommodation groove 411 and are arranged corresponding to the first rotation limiting surface 61. Avoidance grooves 90 for preventing interference between the first rotation limiting surface 61 and the second rotation limiting surface 62 are arranged on both sides of the wall surface of the accommodation groove 411 where the second rotation limiting surface 62 is located. In this embodiment, the two first rotation limiting surfaces 61 are arranged opposite to each other and symmetrically.

[0071] Refer to Figure 3 As shown, a convex column 311 protrudes from one end of the moving iron core 31 away from the electromagnet assembly 32. Correspondingly, a concave position 422 matching the convex column 311 is recessed at one end of the buffer heat insulation ring 42 close to the moving iron core 31. The concave position 422 is clamped on the convex column 311. A positioning groove 312 is arranged on the outer periphery of the moving iron core 31 at the convex column 311. Correspondingly, the buffer heat insulation ring 42 is provided with a positioning convex portion 423 matching the positioning groove 312. The positioning convex portion 423 is clamped in the positioning groove 312. One end of the buffer heat insulation ring 42 close to the moving iron core 31 is fixed to one end of the moving iron core 31 away from the electromagnet assembly 32 by structural adhesive. An annular groove 431 is formed on the outer periphery of the plunger rod 43. A plug hole 424 and a first glue injection hole 425 communicating with the second installation groove 421 and corresponding to the annular groove 431 are formed on the outer periphery of the buffer heat insulation ring 42. A second glue injection hole 426 corresponding to the bottom of the plunger rod 43 is further formed on the outer periphery of the buffer heat insulation ring 42. A pin is inserted through the plug hole 424 and is clamped in the annular groove 431 to complete the positioning of the plunger rod 43 in the second installation groove 421. Structural adhesive is filled through the first glue injection hole 425 and the second glue injection hole 426 to complete the fixation of the plunger rod 43 in the second installation groove 421.

[0072] Referring to Figure 4 as shown, the sealing assembly 70 includes an O-ring 71 and a sealing ring 72. The sealing ring 72 has a through-hole 721. At both ends of the through-hole 721 of the sealing ring 72, a first annular extension 722 and a second annular extension 723 are respectively extended. A three-stage stepped groove 107 is formed on the wall surface of the plunger moving groove 104. The positioning ring 41 and the plunger rod 43 together fix the sealing ring 72 to a section of the three-stage stepped groove 107 close to the positioning ring 41. The plunger rod 43 fixes the first annular extension 722 to a section of the three-stage stepped groove 107 away from the positioning ring 41. The sealing ring 72 and the first annular extension 722 fix the O-ring 71 to the middle section of the three-stage stepped groove 107. The plunger rod 43 fixes the second annular extension 723 to the through-hole 412;

[0073] Preferably, the extension length of the first annular extension 722 is greater than that of the second annular extension 723. The first annular extension 722 is arranged with a smaller upper opening and a larger lower opening. The second annular extension 723 is arranged with a larger upper opening and a smaller lower opening. The setting of the second annular extension 723 can further prevent the reagent from entering the positioning ring 41.

[0074] The working principle of this embodiment is described in detail as follows:

[0075] When a specified current is applied to the coil 324, a magnetic field is generated. The magnetic field sequentially passes through the iron shell 325, the fixed iron core 323 and the moving iron core 31 to form a magnetic circuit. Finally, an electromagnetic force is formed between the fixed iron core 323 and the moving iron core 31 to attract the moving iron core 31, driving the plunger rod 43 to move downward, so that a negative pressure is formed in the plunger moving groove 104 of the pump body 10, and the liquid in the metering channel 103 is sucked;

[0076] After the liquid suction is completed, the coil 324 is powered off. The moving iron core 31, the buffer heat insulation ring 42 and the plunger rod 43 are separated from the fixed iron core 323 and move upward under the restoring force of the elastic member 328 until they are abutted against the pump body 10, completing the liquid discharge action.

[0077] The design focus of the present invention is:

[0078] Specifically, the moving iron core is connected to the plunger rod through the buffer heat insulation ring. The buffer heat insulation ring can prevent the heat of the moving iron core from being transferred to the plunger rod on the one hand, and can avoid the plunger rod from hitting the pump body too fast on the other hand. A first rotation limiting structure is provided between the positioning ring and the pump body to limit the relative rotation of the positioning ring with respect to the pump body. A second rotation limiting structure is provided between the buffer heat insulation ring and the positioning ring to limit the relative rotation of the buffer heat insulation ring with respect to the positioning ring, which can ensure that the plunger rod hits the same position in the plunger moving groove each time, making the metering more accurate. At the same time, the requirement for the flatness processing of the metering pump can be reduced, and thus the production cost can be reduced.

[0079] As described above, it is only the preferred embodiment of the present invention, and does not impose any limitation on the technical scope of the present invention. Therefore, any minor modification, equivalent change and modification 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 high-precision electromagnetic plunger metering pump, characterized in that: include: A pump body, wherein the pump body is provided with a first mounting groove and a suction and discharge port, the pump body is provided with a quantitative channel connected to the suction and discharge port, an end of the quantitative channel away from the suction and discharge port is connected to the first mounting groove through a plunger movable groove, and the pump body is also provided with a first liquid inlet channel and a first liquid outlet channel; A valve body, the valve body is provided with a main channel and a second liquid inlet channel and a second liquid outlet channel which can be communicated with the main channel, the main channel is connected to the suction and discharge port, the second liquid inlet channel is connected to the first liquid inlet channel, and the second liquid outlet channel is connected to the first liquid outlet channel; An electromagnetic control device, the electromagnetic control device comprising a movable moving iron core and an electromagnet assembly for controlling the movement of the moving iron core; The plunger assembly comprises a positioning ring, a buffer heat-insulating ring, and a plunger rod. The positioning ring is arranged in the first mounting groove. The positioning ring is provided with a receiving groove and a through hole connected to the receiving groove for the plunger rod to pass through. A first rotation limiting structure is arranged between the positioning ring and the pump body. The first rotation limiting structure comprises a positioning pin and a positioning hole. The outer periphery of the positioning ring and the wall surface of the first mounting groove are provided with the positioning hole. The positioning pin is inserted into the positioning hole. The first rotation limiting structure is used to prevent the positioning ring from rotating relative to the pump body. The electromagnetic control device fixes the positioning ring in the first mounting groove. The buffer heat-insulating ring is arranged in the receiving groove and connected to the moving iron core. A second rotation limiting structure is arranged between the buffer heat-insulating ring and the positioning ring. The second rotation limiting structure comprises a first A rotation limiting surface and a second rotation limiting surface, wherein the first rotation limiting surface is provided with two adjacent or oppositely arranged surfaces, the two first rotation limiting surfaces are provided on the outer periphery of the buffer heat insulation ring, the second rotation limiting surfaces are provided with two surfaces, the two second rotation limiting surfaces are provided on the wall surface of the accommodating groove and are provided corresponding to the first rotation limiting surface, the wall surface of the accommodating groove is provided with avoidance grooves on both sides of the second rotation limiting surface for preventing the first rotation limiting surface from interfering with the second rotation limiting surface, the buffer heat insulation ring is provided with a second mounting groove at one end away from the moving iron core, the plunger rod is provided in the second mounting groove, the end of the plunger rod away from the buffer heat insulation ring passes through the through hole and extends into the plunger movable groove, a sealing assembly is provided between the outer periphery of the plunger rod and the plunger movable groove, and the electromagnet assembly drives the plunger rod to move in the plunger movable groove through the moving iron core.

2. A high-precision electromagnetic plunger metering pump according to claim 1, characterized in that: A protruding column is convexly provided at one end of the moving iron core away from the electromagnet assembly, and correspondingly, a recess matching the protruding column is concavely provided at one end of the buffer heat insulation ring close to the moving iron core, and the recess is clamped in the protruding column. The moving iron core is provided with a positioning groove on the outer periphery of the protruding column, and correspondingly, the buffer heat insulation ring is provided with a positioning convex portion matching the positioning groove, and the positioning convex portion is clamped in the positioning groove.

3. A high-precision electromagnetic plunger metering pump according to claim 1, characterized in that: One end of the buffer heat-insulating ring close to the moving iron core is fixed to one end of the moving iron core away from the electromagnet assembly through structural adhesive.

4. A high-precision electromagnetic plunger metering pump according to claim 1, characterized in that: The sealing assembly includes an O-ring and a sealing ring, the sealing ring has a through hole, the sealing ring is respectively extended with a first annular extension portion and a second annular extension portion at both ends of the through hole, the wall surface of the plunger movable groove is provided with a three-section stepped groove, the positioning ring and the plunger rod together fix the sealing ring to a section of the three-section stepped groove close to the positioning ring, the plunger rod fixes the first annular extension portion to a section of the three-section stepped groove away from the positioning ring, the sealing ring and the first annular extension portion fix the O-ring to the middle section of the three-section stepped groove, and the plunger rod fixes the second annular extension portion to the through hole.

5. A high-precision electromagnetic plunger metering pump according to claim 1, characterized in that: A valve body mounting portion is extended from the side of the pump body, the valve body is fixed on the valve body mounting portion, the quantitative channel includes a transverse section and a first vertical section and a second vertical section connected to the transverse section, the transverse section runs through the valve body mounting portion, the valve body mounting portion is provided with a plug for sealing the end of the transverse section, the suction and discharge port is provided at one end of the first vertical section away from the transverse section, and the plunger movable groove is provided at one end of the second vertical section away from the transverse section.

6. A high-precision electromagnetic plunger metering pump according to claim 5, characterized in that: The valve body is a three-way valve.

7. A high-precision electromagnetic plunger metering pump according to claim 1, characterized in that: The electromagnet assembly includes a pressure plate, a frame, a fixed iron core, a coil, and an iron shell. The pressure plate is fixed on the pump body and is used to fix the positioning ring in the first mounting groove. The iron shell is fixed on the pressure plate and fixes the frame in the iron shell. The frame includes an inner cavity and an outer cavity separated from the inner cavity. The moving iron core is movably arranged at one end of the inner cavity close to the pump body, and the fixed iron core is arranged at one end of the inner cavity away from the pump body. An elastic member for driving the moving iron core to move toward the pump body is sandwiched between the fixed iron core and the moving iron core, and the coil is arranged in the outer cavity.

8. A high-precision electromagnetic plunger metering pump according to claim 7, characterized in that: The electromagnet assembly also includes an adjusting nut. One end of the fixed iron core away from the moving iron core extends out of the iron shell and is provided with a threaded portion. The adjusting nut is connected to the threaded portion and is used to adjust the position of the fixed iron core in the inner cavity.

Images