Miniature electromagnetic valve

Abstract

The utility model relates to the technical field of electromagnetic valves, in particular to a miniature electromagnetic valve. The miniature electromagnetic valve comprises a shell, a framework and a control assembly, the framework is divided into a control part and an airflow part, the control part is provided with a flow guide cavity, and the airflow part is provided with an air outlet cavity and an air release cavity which are communicated through the flow guide cavity; and the silencing filter element is mounted in the air leakage cavity, so that the exhaust noise is effectively reduced. In addition, the partial design of the end cover can better protect the internal structure and improve the sealing stability.

Description

Technical Field

[0001] This application relates to the technical field of solenoid valves, and in particular to a miniature solenoid valve. Background Technology

[0002] Miniature solenoid valves are widely used in products such as massagers and blood pressure monitors that require precise pressure maintenance and rapid deflating. A miniature solenoid valve mainly consists of a housing, a frame, and a control component. The frame has an outlet chamber and a deflation chamber. The deflation chamber is generally used to connect to an inflatable air bag to maintain pressure in the corresponding product. The control component can control the connection or disconnection between the outlet chamber and the deflation chamber, thereby enabling the inflatable air bag to switch between a deflation state and a pressure-maintaining state.

[0003] As these products increasingly demand higher user experience, miniature solenoid valves not only need excellent flow rate and airtightness, but also must effectively reduce noise generated during operation to improve the overall product quality. In related technologies, a silencer filter element is typically installed in the gas flow path to reduce noise in miniature solenoid valves. Specifically, the silencer filter element can scatter sound wave energy, thereby achieving a noise reduction effect. However, in actual use, the silencer filter element is easily displaced or even detached from the vent groove due to air pressure, resulting in unstable noise reduction performance of the miniature solenoid valve. Utility Model Content

[0004] In order to improve the stability of the noise reduction effect of miniature solenoid valves, the purpose of this application is to provide a miniature solenoid valve.

[0005] The miniature solenoid valve provided in this application adopts the following technical solution:

[0006] A miniature solenoid valve includes a housing, a frame, and a control component. The control component is mounted on the frame, which includes a control section and an airflow section. The control section has a guide cavity, and the airflow section has an outlet cavity and a vent cavity. The outlet cavity and the vent cavity are connected through the guide cavity. A silencer filter is installed in the vent cavity. The housing includes a shell and an end cap, with an installation space formed between the shell and the end cap. The control section is located within the installation space. The airflow section passes through the end cap and is partially located within the installation space. The end cap has an installation hole for the airflow section to pass through. The vent cavity has a vent outlet, and the inner wall of the installation hole partially blocks the vent outlet of the vent cavity.

[0007] By adopting the above technical solution, the end cap partially blocks the vent outlet to prevent the silencer filter element from detaching from the vent outlet, thus ensuring that the silencer filter element can be stably installed in the vent chamber, thereby improving the noise reduction stability of the miniature solenoid valve. Furthermore, as a conventional component of a solenoid valve, the end cap also has a necessary mounting hole, requiring no additional cost. Therefore, this miniature solenoid valve achieves stable noise reduction without incurring additional costs.

[0008] Optionally, the control unit and the airflow unit are integrally molded.

[0009] By adopting the above technical solution, the control unit and the airflow unit are integrally molded, that is, the frame itself is an integrally molded structure, which makes the assembly of the miniature solenoid valve simple.

[0010] Optionally, the control unit and the airflow unit can be ultrasonically fused together or sealed together using a sealing ring.

[0011] By adopting the above technical solution, if the airflow structure is relatively complex, the control part and the airflow part can be produced separately first, and then connected by ultrasonic melting, or the connection between the control part and the airflow part can be pressed by the end cap and the shell and sealed by the sealing ring, which facilitates the production and processing of the skeleton under complex airflow structure.

[0012] Optionally, the control unit has a mounting end face, and the height difference H between the inner wall of the vent chamber and the mounting end face is less than the thickness D of the end cover.

[0013] By adopting the above technical solution and controlling the difference between the height difference H and the thickness D according to actual design needs, the opening size of the venting chamber can be finely adjusted while ensuring the stability of the silencer filter element. In some scenarios where only the opening size of the venting chamber needs to be finely adjusted to meet the parameter conditions, the parameters can be adjusted by changing the thickness of the end cap, thereby improving the multi-parameter adaptability of the miniature solenoid valve.

[0014] Optionally, the venting chamber is a cuboid hole.

[0015] By adopting the above technical solution, the rectangular hole can increase the airflow area, and the related structure on the airflow section that matches the rectangular hole can also be designed as a rectangle. The various cavities of the injection mold are mainly formed by cutting. Rectangles are easier to control errors in the injection mold processing compared to cylindrical shapes, thereby simplifying the mold production process.

[0016] Optionally, the noise-absorbing filter element is arranged in a columnar shape.

[0017] By adopting the above technical solution and using rectangular holes, the end face of the columnar silencer filter element can be stably fixed by the two sides of the inner wall of the rectangular holes, thereby improving the installation stability of the columnar silencer filter element.

[0018] Optionally, the venting chamber has a venting inlet that connects to the guide chamber, and the silencer filter element is provided with an air passage groove to avoid the venting inlet, the air passage groove being connected to the venting inlet.

[0019] By adopting the above technical solution, the presence of the air passage groove can reduce the obstruction of the air vent inlet, allowing the airflow in the guide cavity to have a larger contact area with the sound-absorbing filter element, thereby ensuring airflow speed while better reducing noise.

[0020] Optionally, the sound-absorbing filter element is arranged in the form of a four-sided prism, with at least two four-sided prism faces having air passage grooves.

[0021] By adopting the above technical solution, the sound-absorbing filter element with a square prism shape will not roll away and be lost when placed on the assembly workbench. The setting of multiple air passage grooves can reduce the alignment work required in the assembly process, thereby facilitating the production and assembly of miniature solenoid valves.

[0022] Optionally, when the number of air passage grooves on the silencer filter element is even, every two air passage grooves form a group, and the two air passage grooves in a single group are symmetrically arranged with the axis of the silencer filter element as the center.

[0023] By adopting the above technical solution, the symmetrical arrangement of each group of air passage grooves facilitates the production and processing of the silencer filter element, further reducing the alignment work required in the assembly process, thereby facilitating the production and assembly of the miniature solenoid valve.

[0024] Optionally, the control assembly includes a seal, a magnetic rod, a spring, and a coil. The coil is sleeved on the control part of the frame, the magnetic rod is slidably disposed in the guide cavity of the frame, the seal is located at the end of the magnetic rod near the venting cavity, and the spring is sleeved on one end of the magnetic rod.

[0025] By adopting the above technical solution, the opening and closing of the venting inlet of the magnetic rod near or away from the venting chamber can be controlled by turning the coil on and off, thereby realizing the venting or pressure holding of the miniature solenoid valve.

[0026] In summary, this application includes at least one of the following beneficial technical effects:

[0027] 1. The end cap partially blocks the vent outlet to limit the occurrence of the silencer filter element detaching from the vent outlet, thereby improving the noise reduction stability of the miniature solenoid valve;

[0028] 2. The control unit and the airflow unit are integrally formed or connected by ultrasonic melting and sealing ring, which makes the assembly of the miniature solenoid valve simpler and facilitates the production and processing of the skeleton under complex airflow structure.

[0029] 3. The height difference between the inner wall of the vent chamber and the mounting end face is greater than the thickness of the end cover. This allows for fine adjustment of the vent chamber opening size while ensuring the stability of the silencer filter element, thereby improving the multi-parameter adaptability of the miniature solenoid valve. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application (the coil is not shown);

[0031] Figure 2 This is a cross-sectional structural diagram of an embodiment of this application;

[0032] Figure 3 This is a schematic diagram of the structure of the noise-absorbing filter element according to an embodiment of this application;

[0033] Figure 4 yes Figure 2 A magnified view of part A in the diagram.

[0034] In the diagram: 1. Outer shell; 11. Housing; 12. End cap; 121. Mounting hole; 2. Frame; 21. Control unit; 211. Guide cavity; 22. Airflow unit; 221. Exhaust cavity; 222. Vent cavity; 2221. Vent outlet; 2222. Vent inlet; 3. Control component; 31. Seal; 32. Magnetic rod; 33. Elastic noise reduction component; 34. Spring; 35. Coil; 4. Silencing filter element; 41. Air passage groove. Detailed Implementation

[0035] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail below.

[0036] This application discloses a miniature solenoid valve, which can be either a normally closed solenoid valve or a normally open solenoid valve depending on actual needs. Their internal structures are basically the same, differing only in the installation positions of a few components, leading to different states of the solenoid valve under normal conditions. In the various embodiments of this application, a normally closed solenoid valve is used as an example for description, while normally open solenoid valves are not further elaborated. However, it is understood that the scope of protection in this application can encompass solutions using normally open solenoid valves.

[0037] A miniature solenoid valve mainly includes a housing 1, a frame 2, and a control component 3. The housing 1 includes a shell 11 and an end cap 12. The core design point of this application lies in the cooperation relationship between the end cap 12 and the frame 2. The structure other than the housing 1 and the end cap 12 and the control component 3 can be replaced with relevant structures well known to those skilled in the art in solenoid valves such as those disclosed in CN220668537U, CN217784343U, CN217723493U, or CN215778044U.

[0038] Reference Figure 1 and Figure 2 A miniature solenoid valve includes a housing 1, a frame 2, and a control component 3.

[0039] The outer casing 1 provides space for the installation of the frame 2 and the control components 3, thus protecting the frame 2 and the control components 3. The outer casing 1 includes a housing 11 and an end cap 12. The housing 11 is a metal piece with a longitudinal cross-section resembling a "U" shape; those skilled in the art often refer to the housing 11 as a "U-shaped iron." The end cap 12 is a metal sheet with a central through hole, and is riveted to one end of the "U"-shaped opening of the housing 11 by press-fitting. An installation space is formed between the housing 11 and the end cap 12.

[0040] The frame 2 is typically an injection-molded part, comprising a control unit 21 and an airflow unit 22. The control unit 21 and the airflow unit 22 can be integrally molded within an injection mold, or they can be two separate injection-molded parts ultrasonically fused together. Alternatively, the connection between the control unit 21 and the airflow unit 22 can be pressed together by an end cap 12 and the housing 11, and sealed with a sealing ring. In this embodiment, the control unit 21 and the airflow unit 22 are integrally molded. The control unit 21 is located within the installation space, and the airflow unit 22 passes through the end cap 12 and is partially located within the installation space.

[0041] The control unit 21 is arranged in an "I" shape, with a through-flow guide cavity 211. The airflow unit 22 has an outlet cavity 221 and a vent cavity 222, which are connected through the guide cavity 211. Specifically, the outlet cavity 221 can be connected to a pump or air bag, etc., as required by the design. The outlet cavity 221 is connected to the guide cavity 211, and its axis is parallel to the axis of the guide cavity 211. The vent cavity 222 is connected to the guide cavity 211, and the gas flow direction of the vent cavity 222 is perpendicular to the gas flow direction of the guide cavity 211. The vent cavity 222 can be a cuboid hole, a circular hole, an elliptical hole, or an irregularly shaped hole. In this embodiment, the vent cavity 222 is a cuboid hole.

[0042] To improve noise reduction, the end of the venting chamber 222 furthest from the axis of the guide chamber 211 is defined as the venting outlet 2221. A silencer filter element 4 is installed inside the venting chamber 222. The silencer filter element 4 can be installed into the venting chamber 222 from the venting outlet 2221 and has an interference fit with the venting chamber 222. The silencer filter element 4 is a hard sintered part with several fine pores. The number and size of the fine pores can be set according to actual parameter requirements. The silencer filter element 4 is columnar. In this embodiment, the silencer filter element 4 is a quadrangular prism, with the axis of the quadrangular prism parallel to the axis of the guide chamber 211. The edges can be chamfered according to actual design requirements.

[0043] Reference Figure 2 and Figure 3 The filter element 4 has an air passage groove 41 for avoiding the vent inlet 2222. The air passage groove 41 extends along the axial direction of the guide cavity 211 and passes close to the vent inlet 2222, so that the air passage groove 41 communicates with the vent inlet 2222. The four cylindrical surfaces of the silencer filter element 4 may have partial or complete air passage grooves 41. In this embodiment, there are two air passage grooves 41, which are symmetrically arranged about the axis of the silencer filter element 4.

[0044] Reference Figure 2 and Figure 4To improve the installation stability of the silencer filter element 4, the through hole in the center of the end cap 12 is defined as the mounting hole 121. The axis of the mounting hole 121 is parallel to or coincides with the axis of the guide cavity 211, and the airflow section 22 passes through the mounting hole 121. The inner wall of the mounting hole 121 partially blocks the vent outlet 2221 of the vent cavity 222. That is, the end face of the control section 21 near the airflow section 22 is defined as the mounting end face, and the height difference H between the inner wall of the vent cavity 222 and the mounting end face is less than the thickness D of the end cap 12. The difference between the height difference H and the thickness D is controlled according to the actual design requirements.

[0045] Reference Figure 2 The control component 3 includes a seal 31, a magnetic rod 32, an elastic noise reduction component 33, a spring 34, and a coil 35. The seal 31 and the elastic noise reduction component 33 are both rubber parts, while the magnetic rod 32 is a metal part. It should be noted that if a nozzle communicating with the air guide cavity 211 is provided on the housing 11, the elastic noise reduction component 33 can also serve to seal the airflow channel of the nozzle.

[0046] The coil 35 is sleeved on the control part 21 of the frame 2, the magnetic rod 32 is slidably disposed in the guide cavity 211 of the frame 2, the sealing member 31 is located at the end of the magnetic rod 32 near the vent cavity 222, the elastic noise reduction member 33 is located at the end of the magnetic rod 32 away from the vent cavity 222, and the spring 34 is partially sleeved on one end of the magnetic rod 32. The positional relationship and connection relationship of the control components 3 are well known to those skilled in the art and will not be described in detail here.

[0047] The implementation principle of a miniature solenoid valve in this application embodiment is as follows:

[0048] ① During pressure holding, the coil 35 is de-energized, and the magnetic rod 32, under the elastic force of the spring 34, drives the sealing element 31 to press against the vent inlet 2222 of the sealed vent chamber 222. At this time, the vent chamber 222 is not connected to the outlet chamber 221, and the air pressure inside the structure connected to the outlet chamber 221 can remain stable.

[0049] ② During venting, the coil 35 is energized to generate a magnetic field. Under the action of the magnetic field, the magnetic rod 32 overcomes the elastic force of the spring 34 to drive the seal 31 to disengage from the venting inlet 2222. At this time, the venting inlet 2222 of the venting chamber 222 opens to connect the venting chamber 222 with the outlet chamber 221. The gas in the structure connected to the outlet chamber 221 enters the venting chamber 222 after passing through the guide chamber 211. When it passes through the silencer filter 4 in the venting chamber 222, the airflow noise is reduced. The noise-reduced airflow is finally discharged from the venting outlet 2221 of the venting chamber 222.

[0050] The embodiments described herein are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be included within the scope of protection of this application.

Claims

1. A miniature solenoid valve, characterized in that, It includes a shell (1), a frame (2), and a control component (3), wherein the control component (3) is mounted on the frame (2). The frame (2) includes a control unit (21) and an airflow unit (22). The control unit (21) has a guide cavity (211), and the airflow unit (22) has an outlet cavity (221) and an exhaust cavity (222). The outlet cavity (221) and the exhaust cavity (222) are connected through the guide cavity (211). A silencer filter element (4) is installed in the exhaust cavity (222). The outer casing (1) includes a housing (11) and an end cap (12), with an installation space formed between the housing (11) and the end cap (12). The control unit (21) is located within the installation space, and the airflow unit (22) passes through the end cap (12) and is partially located within the installation space. The end cap (12) has a mounting hole (121) through which the airflow section (22) passes, and the venting chamber (222) has a venting outlet (2221). The inner wall of the mounting hole (121) partially blocks the venting outlet (2221) of the venting chamber (222).

2. A miniature solenoid valve according to claim 1, characterized in that, The control unit (21) and the airflow unit (22) are integrally formed.

3. A miniature solenoid valve according to claim 1, characterized in that, The control unit (21) and the airflow unit (22) are ultrasonically fused together or sealed together by a sealing ring.

4. A miniature solenoid valve according to claim 1, characterized in that, The control unit (21) has a mounting end face, and the height difference H between the inner wall of the venting chamber (222) and the mounting end face is less than the thickness D of the end cover (12).

5. A miniature solenoid valve according to claim 1, characterized in that, The venting chamber (222) is a cuboid hole.

6. A miniature solenoid valve according to claim 1 or 5, characterized in that, The noise-absorbing filter element (4) is arranged in a columnar shape.

7. A miniature solenoid valve according to claim 6, characterized in that, The venting chamber (222) has a venting inlet (2222) that communicates with the flow guiding chamber (211), and the sound-absorbing filter element (4) is provided with an air passage groove (41) for avoiding the venting inlet (2222), and the air passage groove (41) communicates with the venting inlet (2222).

8. A miniature solenoid valve according to claim 7, characterized in that, The noise-absorbing filter element (4) is arranged in the form of a quadrangular prism, and the air passage groove (41) is provided on at least two quadrangular prism surfaces.

9. A miniature solenoid valve according to claim 8, characterized in that, When the number of air passage grooves (41) on the silencer filter element (4) is even, each pair of air passage grooves (41) forms a group, and the two air passage grooves (41) in a single group are symmetrically arranged with the axis of the silencer filter element (4) as the center.

10. A miniature solenoid valve according to claim 1, characterized in that, The control component (3) includes a seal (31), a magnetic rod (32), a spring (34), and a coil (35). The coil (35) is sleeved on the control part (21) of the frame (2). The magnetic rod (32) is slidably disposed in the flow guide cavity (211) of the frame (2). The seal (31) is located at one end of the magnetic rod (32) near the vent cavity (222). The spring (34) is partially sleeved on one end of the magnetic rod (32).

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