Solenoid valve with structure capable of overcoming adhesion effect

Abstract

The utility model provides an electromagnetic valve with a structure capable of overcoming adhesion effect, which is characterized in that a conical head is formed at the bottom end of a core rod, and an annular groove is formed on the peripheral surface of a rod body close to the conical head; a connecting sleeve is arranged between the sealing plug and the core rod, a sleeve body of the connecting sleeve is embedded into the containing cavity of the core rod and is in interference fit with the containing cavity of the core rod, a lower hole section of a sleeve hole is an equal-diameter section, an upper hole section of the sleeve hole is a horn mouth section, an inner blocking shoulder body is formed between the upper hole section and the lower hole section, and the hole diameter of a hole opening defined by the inner shoulder body is smaller than that of the lower hole section. A gap for containing the conical head of the core rod is formed between the bottom end face of the connecting sleeve and the bottom of the core rod containing cavity, and the lower step face of the annular groove and the bottom end face of the connecting sleeve can form abutting limiting. The electromagnetic valve is simple in structure, the adhesion effect caused by negative pressure can be effectively overcome by fully utilizing electromagnetic force only by simply machining an original core rod and additionally arranging the connecting sleeve, the reaction speed of the electromagnetic valve is increased, and the sealing effect cannot be affected.

Description

Technical Field

[0001] The utility model belongs to the field of electromagnetic valves, in particular to an electromagnetic valve with a structure for overcoming adhesion effects. Background Art

[0002] Solenoid valves are widely used in fuel tank leak diagnosis systems as products that block the outside atmosphere from entering a closed space when diagnosing fuel tank leaks. Due to the particularity of the fuel tank's vapor medium, and the fact that some fuel vapor will always evaporate from the tank, the tank will expand and contract after being sealed for a long time. When the temperature of the tank drops, if the solenoid valve is closed, a negative pressure effect will occur, causing the rubber plug to be adsorbed on the sealing hole. At the moment the solenoid valve is opened, an adhesion effect will easily occur, causing it to get stuck. Specifically, Figure 1 As shown, when the solenoid valve is not energized, the first spring 1 presses the moving iron core 3 together with the core rod 6 through elastic force, and presses the sealing gasket 71 fixed on the lower end face of the sealing plug 7 onto the sealing hole 8, thereby sealing the sealing hole 8. In order to avoid processing and assembly errors that cause the sealing gasket 71 to fail to effectively seal the sealing hole, the core rod 6 and the sealing plug 7 need to be loosely matched rather than fixedly connected, that is, the sealing plug 7 as shown in the figure is provided with a core rod accommodating cavity 72 facing the upper end face of the core rod 6, the lower end of the core rod 6 extends into the core rod accommodating cavity 72, and the lower end face of the core rod can abut against the bottom wall of the core rod accommodating cavity 72 to transmit the downward pressure, and a gap is left between the circumferential surface of the core rod 6 and the inner wall of the core rod accommodating cavity 72, so that there is enough margin for automatic leveling during the downward pressing of the sealing plug 7; but this also requires a second spring 9 arranged between the sealing plug 7 and the wall of the sealing hole 8 to provide the sealing plug 7 with an upward elastic force to make it rise and thus release the blockage. Figure 2 As shown, when the gas entering the sealing hole generates a negative pressure of P1 after the temperature drops, the pressure in the valve body is P2 (usually atmospheric pressure atm), at this time ΔP=P1-P2 increases, and the sealing plug will be subjected to an additional force F of ΔP*sealing area S. At this time, the sealing gasket 71 and the sealing surface are attached to each other, generating an adsorption effect. The conventional choice is to increase the elastic force of the second spring 9, but it cannot effectively break the adsorption effect, and the lifting and separation of the sealing plug cannot be significantly accelerated. Moreover, the reset elastic force of the second spring 9 is too large, which will also have a negative impact on the sealing effect. Utility Model Content

[0003] In view of the problems existing in the prior art, the utility model provides the following technical solutions:

[0004] An electromagnetic valve with a structure for overcoming adhesion effect, wherein a yoke, a static iron core and a moving iron core are arranged in the valve body, the static iron core is arranged on the upper part of the valve body, the moving iron core is arranged below the static iron core, and a first spring is arranged between the static iron core and the moving iron core; a core rod is coaxially fixedly connected to the bottom of the moving iron core, and a sealing diaphragm is fixed to the middle of the core rod; a sealing plug is provided with a core rod accommodating cavity facing the upper end face of the core rod, the lower end of the core rod extends into the core rod accommodating cavity, and a second spring is arranged between the sealing plug and the sealing hole wall, characterized in that a conical head is formed at the bottom end of the core rod, and an annular groove is arranged on the circumferential surface of the rod body adjacent to the conical head, so that a lower step surface and an upper step surface are formed on the rod body at the lower and upper ends of the annular groove respectively; between the sealing plug and the core rod A connecting sleeve is provided in between, and the sleeve body of the connecting sleeve is embedded in the core rod accommodating cavity and has an interference fit therewith. The sleeve hole of the connecting sleeve 12 is divided into a lower hole section and an upper hole section from bottom to top, the lower hole section is an equal-diameter section, and the upper hole section is a bell-mouth section with a gradually increasing aperture from bottom to top. An annular inner shoulder body extending radially inward is formed between the upper and lower hole sections, and the hole diameter of the inner shoulder hole opening surrounded by the inner shoulder body is smaller than the hole diameter of the lower hole section; the outer diameter of the lower step surface is greater than or equal to the hole diameter of the lower hole section; a gap is formed and maintained between the bottom end face of the connecting sleeve and the bottom of the core rod accommodating cavity for accommodating the conical head of the core rod, and the lower step surface is located below the bottom end face of the connecting sleeve and the two can form abutment limit.

[0005] Furthermore, the entire connecting sleeve is made of plastic material.

[0006] Furthermore, a sealing gasket is fixedly provided at the bottom end of the sealing plug.

[0007] Furthermore, a receiving cavity is provided on the end surface of the stationary iron core facing the moving iron core, the top of the first spring is received and abutted in the receiving cavity, and the bottom of the first spring abuts against the top of the moving iron core.

[0008] Furthermore, the sleeve body at the top end of the connecting sleeve extends radially outward to form an annular outer shoulder body, and the second annular shoulder body abuts against the upper end surface of the sealing plug to limit the position.

[0009] Furthermore, the diameter of the core rod at the annular groove is smaller than the hole diameter of the inner shoulder hole, so that a gap is also left between the core rod and the connecting sleeve.

[0010] Furthermore, the distance between the lower step surface and the upper step surface is greater than the overall thickness of the connecting sleeve.

[0011] Furthermore, the sealing plug is entirely made of plastic material.

[0012] The utility model has a simple structure, and only requires simple processing of the original core rod and the addition of a connecting sleeve, so that the electromagnetic force can be fully utilized to effectively overcome the adhesion effect caused by negative pressure, thereby improving the response speed of the electromagnetic valve without affecting the sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and the description thereof are used to explain the present invention and do not constitute an improper limitation on the present invention. A person of ordinary skill in the art can obtain other relevant drawings based on these drawings without making any creative effort.

[0014] Figure 1 It is a schematic diagram of the structure of a solenoid valve in the prior art;

[0015] Figure 2 for Figure 1 Enlarged schematic diagram of the dotted circle part.

[0016] Figure 3 It is a schematic diagram of the main structural improvements of the utility model.

[0017] Reference numerals in the figures:

[0018] Valve body 1; static iron core 2; moving iron core 3; yoke 4; first spring 5; core rod 6; sealing plug 7; sealing gasket 71; core rod accommodating chamber 72; sealing hole 8; second spring 9; sealing diaphragm 11; connecting sleeve 12; lower hole section 121; upper hole section 122; inner shoulder body 123; outer shoulder body 124; conical head 61; annular groove 62; lower step surface 621; upper step surface 622. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0020] In the description of the embodiments of the present invention, it should be noted that the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the application product is usually placed when in use, or is the orientation or position relationship commonly understood by technical personnel in this field. It is only for the convenience of describing the present invention or simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operate in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0021] The term "plurality" in the present invention refers to more than two (including two). The terms "first", "second" and the like are only used to distinguish descriptions and should not be understood as indicating or implying relative importance.

[0022] Unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0023] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0024] Most of the structures of the utility model Figure 1 The same as the prior art shown, a yoke 4, a static iron core 2 and a moving iron core 3 are arranged in the valve body 1, the static iron core 2 is arranged on the upper part of the valve body, and the moving iron core 3 is arranged below the static iron core 2, and the static iron core 2 is provided with a accommodating cavity on the end face facing the moving iron core, the top of the first spring 5 is accommodated and abutted in the accommodating cavity, and the bottom of the first spring 5 abuts against the top of the moving iron core 3; a core rod 6 is coaxially fixed to the bottom of the moving iron core to move together with the moving iron core, and a sealing diaphragm 11 is fixed to the middle of the core rod 6; a core rod accommodating cavity 72 is opened on the upper end face of the sealing plug 7 towards the core rod 6, the lower end of the core rod 6 extends into the core rod accommodating cavity 72, and a sealing gasket 72 is fixed to the bottom end of the sealing plug 7.

[0025] The improvements are:

[0026] like Figure 3 As shown, the core rod 6 has also undergone corresponding shape changes: an annular groove 62 is provided on the circumferential surface of the rod body above the conical head 61 near the bottom end of the core rod 6, so that the rod body at the lower end and the upper end of the annular groove 62 respectively forms a lower step surface 621 and an upper step surface 622; at the same time, a connecting sleeve 12 is added between the sealing plug 7 and the core rod 6, and the connecting sleeve 12 is made of plastic material as a whole, so that it has a certain rigidity and the ability to be slightly deformed; the sleeve body of the connecting sleeve 12 is embedded in the core rod accommodating cavity 72 of the sealing plug 7 and has an interference fit therewith, and the sleeve hole of the connecting sleeve 12 is formed by the lower It is divided into a lower hole section 121 and an upper hole section 122 from top. The lower hole section 121 is arranged as an equal-diameter section with a constant aperture in the axial direction, and the upper hole section is arranged as a bell-mouth section with an aperture gradually increasing from bottom to top, so as to facilitate the guided insertion of the conical head 61 of the core rod. A radially inwardly extending annular inner shoulder body 123 is formed in the sleeve hole between the upper and lower hole sections. Therefore, the hole diameter of the inner shoulder hole opening surrounded by the inner shoulder body 123 is smaller than the hole diameter of the lower hole section 121 of the sleeve hole of the connecting sleeve 12; the outer diameter of the lower step surface 621 of the core rod 6 is greater than or equal to the hole diameter of the lower hole section 12.

[0027] The conical head 61 of the core rod 6 utilizes its conical structure and the ability of the connecting sleeve 12 to be slightly deformed as a whole, and after passing through the upper hole section 122, the inner shoulder body 123 and the lower hole section 121, the connecting sleeve 12 is completely sleeved in the annular groove 62; the connecting sleeve 12 is squeezed into the accommodating cavity of the sealing plug 7, and the two are fixed by interference fit, and the conical head 61 of the core rod is located between the bottom end surface of the connecting sleeve 12 and the bottom of the accommodating cavity 72 with a certain amount of movable margin, and the lower step surface 621 is placed below the bottom end surface of the connecting sleeve 12 and the two can form abutment limit, so that when the core rod 6 is lifted, the abutment limit provides a lifting force for the sealing plug 7 through the connecting sleeve.

[0028] When possible, even if the lower step surface 621 above the conical head 61 fails to form an abutment limit with the bottom end surface of the connecting sleeve, and the conical head 61 enters the lower hole section 121, there will be an inner shoulder body 123 because its hole diameter is smaller than the lower hole section 121. The inner shoulder body 123 will also effectively play an abutment limit function on the lower step surface 621. That is, the structural design of the inner shoulder body 123 can effectively prevent abutment failure and play the role of ultimate insurance.

[0029] The inner shoulder body 123 is arranged between the upper and lower hole sections (122, 121) instead of being arranged at the bottom end hole opening of the lower hole section 121. The following considerations are taken into account: when the connecting sleeve 12 is first inserted into the sealing plug 7 accommodating chamber 72 and then the conical head 61 is inserted, after the conical head 61 breaks through the inner shoulder body 123 downward, the lower hole section 121 has a certain buffering and deceleration effect on it. However, if the inner shoulder body 123 is arranged at the bottom end hole opening of the lower hole section, after the conical head 61 breaks through the inner shoulder body 123 downward, the conical head 61 is likely to directly cause an excessive impact on the bottom of the accommodating chamber 72 of the sealing plug 7 due to the lack of buffering and deceleration.

[0030] Preferably, the sleeve body at the top end of the connecting sleeve 12 extends radially outward to form an annular outer shoulder body 124, and the outer shoulder body 124 is abutted against the upper end surface of the sealing plug 7 to limit the connection sleeve 12 from penetrating too deep into the core rod accommodating cavity 72, thereby forming and maintaining a sufficient gap between the lower end surface of the connecting sleeve 12 and the bottom of the accommodating cavity 72, providing an accommodating space for the conical head 61 of the core rod 6.

[0031] Preferably, the diameter of the core rod 6 at the annular groove 62 is smaller than the diameter of the inner shoulder hole enclosed by the inner shoulder body 123, so that a gap is left between the core rod 6 and the connecting sleeve 12, ensuring that there is still enough automatic leveling margin during the pressing process of the sealing plug 7 to ensure the sealing effect.

[0032] Preferably, the width of the annular groove 62, that is, the distance between the lower step surface 621 and the upper step surface 622, should be greater than the overall thickness of the connecting sleeve 12 to prevent the connecting sleeve 12 from being clamped by the annular groove 62, thereby affecting or even losing the automatic leveling ability of the sealing plug 7.

[0033] In addition, in order to clearly show the core improved structure of the present invention, the above schematic diagrams do not show the structure for guiding the sealing plug 7 in the valve body and other channels and components, but this does not affect the understanding of the present invention by those skilled in the art.

[0034] Working principle: When the solenoid valve is powered by the electric core 3 and moves upward, the lower step surface 621 above the conical head 61 abuts against the bottom end surface of the connecting sleeve 12 or the inner shoulder 123 and will instantly carry the connecting sleeve 12, and the connecting sleeve 12 will then carry the sealing plug 7 upward. The instantaneous starting force of the solenoid valve will destroy the adsorption effect of the sealing plug 7 to ensure that the sealing plug 7 can be pulled upward by the core rod 6 the moment it is subjected to the electromagnetic force.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A solenoid valve with a structure for overcoming adhesion effect, wherein a yoke (4), a static iron core (2) and a moving iron core (3) are arranged in a valve body (1), wherein the static iron core is arranged at the upper part of the valve body, and the moving iron core is arranged below the static iron core, and a first spring (5) is arranged between the static iron core and the moving iron core; a core rod (6) is coaxially fixedly connected to the bottom of the moving iron core, and a sealing diaphragm (11) is fixed in the middle of the core rod; a sealing plug (7) is provided with a core rod accommodating cavity (72) toward the upper end surface of the core rod, and the lower end of the core rod extends into the core rod accommodating cavity, and a second spring (9) is arranged between the sealing plug and the hole wall of the sealing hole (8), characterized in that: A conical head (61) is formed at the bottom end of the core rod, and an annular groove (62) is provided on the peripheral surface of the rod body adjacent to the conical head (61), so that a lower step surface (621) and an upper step surface (622) are formed on the rod body at the lower and upper ends of the annular groove respectively; a connecting sleeve (12) is provided between the sealing plug and the core rod, the sleeve body of the connecting sleeve is embedded in the core rod accommodating cavity (72) and is interference fit therewith, and the sleeve hole of the connecting sleeve (12) is divided into a lower hole section (121) and an upper hole section (122) from bottom to top, the lower hole section is a section of equal diameter, and the upper hole section is a section of equal diameter. The hole section is a bell-mouth section with a gradually increasing hole diameter from bottom to top, and an annular inner shoulder body (123) extending radially inward is formed between the upper and lower hole sections, and the hole diameter of the inner shoulder hole opening surrounded by the inner shoulder body is smaller than the hole diameter of the lower hole section; the outer diameter of the lower step surface is greater than or equal to the hole diameter of the lower hole section; a gap is formed and maintained between the bottom end surface of the connecting sleeve and the bottom of the core rod accommodating cavity (72) for accommodating the conical head of the core rod, and the lower step surface (621) is located below the bottom end surface of the connecting sleeve and the two can form abutment limit.

2. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: The connecting sleeve is made of plastic material as a whole.

3. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: A sealing gasket is fixedly arranged at the bottom end of the sealing plug.

4. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: The static iron core is provided with a receiving cavity on the end surface facing the moving iron core. The top of the first spring is received and abutted in the receiving cavity, and the bottom of the first spring abuts against the top of the moving iron core.

5. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: The sleeve body at the top end of the connecting sleeve radially extends outward to form an annular outer shoulder body, and the outer shoulder body abuts against the upper end surface of the sealing plug to limit the position.

6. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: The diameter of the core rod at the annular groove (62) is smaller than the hole diameter of the inner shoulder hole, so that a gap is also left between the core rod and the connecting sleeve.

7. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: The distance between the lower step surface (621) and the upper step surface (622) is greater than the overall thickness of the connecting sleeve.

8. The solenoid valve with a structure for overcoming adhesion effect as claimed in claim 1, characterized in that: The sealing plug is made entirely of plastic material.

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