Air valve piston rod sealing structure

Abstract

The invention provides an air valve piston rod sealing structure which comprises a valve body, a piston rod and a sealing ring. The sealing ring is embedded in the inner side of the upper end of the valve body and axially limited with the valve body, and the piston rod can axially and movably penetrate through the valve body and the sealing ring; an annular groove with an opening in the bottom is formed in the lower end of the sealing ring, a first annular contraction part gradually contracting inwards from top to bottom is formed on the inner side of the annular groove, the first annular contraction part is tightly attached to the peripheral wall of the piston rod in a sealed mode, and an annular expansion part gradually expanding outwards from top to bottom is formed on the outer side of the annular groove. The annular expansion part and the inner side wall of the valve body are in interference fit and are tightly sealed; the sealing effect of the sealing ring on the gap between the piston rod and the valve body can be improved, so that the situation of air leakage between the piston rod and the valve body is avoided, and the sealing reliability of the sealing ring on the gap between the piston rod and the valve body can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile seat air valves, and in particular to an air valve piston rod sealing structure. Background Art

[0002] In a vehicle seat height adjustment device, an air valve is an important device for controlling the air path; for example, a height adjustment air valve assembly in a vehicle seat height adjustment device disclosed in Chinese Patent Publication No. CN219618944U; the existing air valve mainly includes a valve body, a piston rod and a sealing ring; the sealing ring is embedded on the inner side of the upper end of the valve body and axially limited with the valve body, and the piston rod is axially movable through the valve body and the sealing ring, and the sealing ring is used to seal the gap between the piston rod and the valve body; however, in the existing air valve structure, there is a disadvantage that the sealing ring has poor sealing reliability between the piston rod and the valve body, which easily leads to air leakage between the piston rod and the valve body. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an air valve piston rod sealing structure, which can improve the sealing effect of the sealing ring on the gap between the piston rod and the valve body to avoid air leakage between the piston rod and the valve body, that is, it can improve the sealing reliability of the sealing ring on the gap between the piston rod and the valve body.

[0004] The present invention provides an air valve piston rod sealing structure, comprising a valve body, a piston rod and a sealing ring; the sealing ring is embedded in the inner side of the upper end of the valve body and is axially limited with the valve body, and the piston rod is axially movably arranged in the valve body and the sealing ring; the lower end of the sealing ring is provided with an annular groove with a bottom opening, and the inner side of the annular groove forms a first annular contraction portion which gradually contracts inward from top to bottom, and the first annular contraction portion is tightly sealed with the outer peripheral wall of the piston rod, and the outer side of the annular groove forms an annular expansion portion which gradually expands outward from top to bottom, and the annular expansion portion is interference fit with the inner side wall of the valve body and is tightly sealed.

[0005] After the present invention adopts the above-mentioned structure, when the air pressure inside the valve body increases, compressed air can enter the annular groove. At this time, the compressed air can squeeze the first annular contraction portion, so that the first annular contraction portion can be further tightly sealed with the outer wall of the piston rod. At the same time, the compressed air can squeeze the annular expansion portion, so that the annular expansion portion can be further tightly sealed with the inner wall of the valve body; that is, after adopting the above-mentioned structure, when the air pressure inside the valve body increases, the sealing effect of the sealing ring on the gap between the piston rod and the valve body can be further improved to avoid air leakage between the piston rod and the valve body, that is, the sealing reliability of the sealing ring on the gap between the piston rod and the valve body can be improved.

[0006] In one possible embodiment, a second annular contraction portion that gradually shrinks inward from bottom to top is provided at the inner edge of the upper end of the sealing ring, and the second annular contraction portion is tightly sealed with the outer peripheral wall of the piston rod; through the provision of the second annular contraction portion, the second annular contraction portion is tightly sealed with the outer peripheral wall of the piston rod, thereby enabling the second annular contraction portion to block dust in the external environment from entering the gap between the sealing ring and the piston rod; in addition, since the second annular contraction portion gradually shrinks inward from bottom to top, the second annular contraction portion has the advantage of good elastic deformation effect, that is, the second annular contraction portion can be reliably tightly attached to the outer peripheral wall of the piston rod, so as to improve the effect of the second annular contraction portion in blocking dust from entering the gap between the sealing ring and the piston rod.

[0007] In a possible embodiment, the inner circumferential wall of the sealing ring is connected to the inner circumferential wall of the first annular contraction portion and the inner circumferential wall of the second annular contraction portion to form an annular cavity; through the setting of the annular cavity, the first annular contraction portion and the second annular contraction portion can have a better elastic deformation effect, so that the first annular contraction portion and the second annular contraction portion can be more reliably attached to the outer circumferential wall of the piston rod and cooperate with the piston rod to form a sealing structure.

[0008] In one possible embodiment, the annular cavity forms an olive-shaped structure along its axial direction with a larger inner diameter in the middle and smaller inner diameters at both ends; by adopting an annular cavity of this shape, the first annular contraction portion and the second annular contraction portion have a better elastic deformation effect, that is, the first annular contraction portion and the second annular contraction portion can be further reliably adhered to the outer circumferential wall of the piston rod and cooperate with the piston rod to form a sealing structure.

[0009] In a possible embodiment, the valve piston rod sealing structure further includes a support ring; the support ring is embedded in the valve body below the sealing ring and is axially limited by the valve body, and the piston rod is movably inserted into the support ring; an annular groove is provided at the upper end of the support ring and in the middle of the radial direction of the support ring, and the support ring located inside the annular groove forms a ring-shaped plug-in portion, the outer peripheral wall of the plug-in portion fits with the inner side wall of the outer edge of the annular groove, and a plurality of vent holes are provided at the bottom of the annular groove at intervals in the circumferential direction, and each vent hole axially passes through the support ring; after adopting this structure, Under the action of the plug-in part on the support ring, the outer peripheral wall of the plug-in part fits with the inner side wall of the outer edge of the annular groove, so that the support ring can support and limit the sealing ring. Through the setting of the vent hole, when compressed air enters the interior of the valve body, the compressed air can flow through the vent hole and squeeze the annular expansion part to deform the annular expansion part. Then the compressed air can enter the annular groove through the gap between the annular expansion part and the plug-in part. At the same time, the compressed air can also enter the annular groove through the gap between the piston rod and the inner peripheral wall of the support ring.

[0010] In a possible embodiment, an annular step is provided on the inner circumferential wall of the upper end of the valve body, and the upper end of the sealing ring abuts against the annular step; by adopting this structure, after the upper end of the sealing ring abuts against the annular step, and under the action of the outer circumferential wall of the plug-in portion and the inner side wall of the outer edge of the annular groove being in contact with each other, axial limitation of the sealing ring can be achieved, that is, the sealing ring can be reliably axially limited inside the valve body; in addition, when the air pressure inside the valve body increases, the piston rod can move upward relative to the valve body. At the same time, under the action of the upper end of the sealing ring abutting against the annular step, the sealing ring can be prevented from moving upward relative to the valve body with the piston rod; when the air pressure inside the valve body decreases, the piston rod can move downward relative to the valve body. At the same time, under the action of the outer circumferential wall of the plug-in portion and the inner side wall of the outer edge of the annular groove being in contact with each other, the support ring can limit the sealing ring from moving downward relative to the piston rod, that is, axial limitation of the sealing ring is achieved.

[0011] In one possible embodiment, an annular rib is provided on the outer circumferential wall of the support ring, and an annular embedding groove is provided on the inner circumferential wall of the valve body, and the annular rib is embedded in the annular embedding groove; by adopting this structure, after the annular rib is embedded in the annular embedding groove, the support ring can be reliably assembled with the valve body and achieve the purpose of axial limitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the three-dimensional structure of the piston rod, sealing ring, support ring and valve body after assembly; Figure 2 This is a schematic diagram of the cross-sectional structure of the piston rod, sealing ring, support ring and valve body after assembly; Figure 3 for Figure 2 The schematic diagram of the structure after enlarging at A in the middle; Figure 4 Schematic diagram of the three-dimensional structure of the sealing ring; Figure 5 Schematic diagram of the three-dimensional structure of the support ring. DETAILED DESCRIPTION

[0013] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of the present application and are not intended to limit the scope of protection of the embodiments of the present application. Those skilled in the art may adjust them as needed to suit specific application scenarios.

[0014] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0015] In the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0016] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] See also Figure 1-5 As shown, the embodiment of the present application discloses a gas valve piston rod sealing structure, including a valve body 1, a piston rod 2 and a sealing ring 3; the sealing ring 3 is embedded in the inner side of the upper end of the valve body 1 and is axially limited with the valve body 1, and the piston rod 2 is axially movable through the valve body 1 and the sealing ring 3; the lower end of the sealing ring 3 is provided with an annular groove 31 with a bottom opening, and the inner side of the annular groove 31 forms a first annular contraction portion 32 which gradually contracts inward from top to bottom, and the first annular contraction portion 32 is tightly sealed with the outer peripheral wall of the piston rod 2, and the outer side of the annular groove 31 forms an annular expansion portion 33 which gradually expands outward from top to bottom, and the annular expansion portion 33 is interference fit with the inner wall of the valve body 1 and tightly sealed.

[0018] A second annular contraction portion 34 which gradually shrinks inward from bottom to top is provided at the inner edge of the upper end of the sealing ring 3, and the second annular contraction portion 34 is tightly sealed with the outer peripheral wall of the piston rod 2; through the provision of the second annular contraction portion, since the second annular contraction portion is tightly sealed with the outer peripheral wall of the piston rod, the second annular contraction portion can prevent dust in the external environment from entering the gap between the sealing ring and the piston rod; in addition, since the second annular contraction portion gradually shrinks inward from bottom to top, the second annular contraction portion has the advantage of good elastic deformation effect, that is, the second annular contraction portion can be reliably tightly attached to the outer peripheral wall of the piston rod, so as to improve the effect of the second annular contraction portion in blocking dust from entering the gap between the sealing ring and the piston rod.

[0019] The inner circumferential wall of the sealing ring 3 is connected to the inner circumferential wall of the first annular contraction part 32 and the inner circumferential wall of the second annular contraction part 34 to form an annular cavity 35; through the setting of the annular cavity, the first annular contraction part and the second annular contraction part can have a better elastic deformation effect, so that the first annular contraction part and the second annular contraction part can be more reliably tightly attached to the outer circumferential wall of the piston rod and cooperate with the piston rod to form a sealing structure.

[0020] The annular cavity 35 forms an olive-shaped structure along its axial direction with a larger inner diameter in the middle and smaller inner diameters at both ends; by adopting an annular cavity of this shape, the first annular contraction portion and the second annular contraction portion have a better elastic deformation effect, that is, the first annular contraction portion and the second annular contraction portion can be further reliably adhered to the outer circumferential wall of the piston rod and cooperate with the piston rod to form a sealing structure.

[0021] The valve piston rod sealing structure also includes a support ring 4; the support ring 4 is embedded in the valve body 1 located below the sealing ring 3 and is axially limited by the valve body 1, and the piston rod 2 is movably inserted into the support ring 4; an annular groove 41 is provided at the upper end of the support ring 4 and in the middle of the radial direction of the support ring 4, and the support ring 4 located inside the annular groove 41 forms a ring-shaped plug-in portion 42, and the outer peripheral wall of the plug-in portion 42 fits with the inner side wall of the outer edge of the annular groove 31, and a plurality of vent holes 43 are provided at the bottom of the annular groove 41 at intervals in the circumferential direction, and each vent hole 43 axially penetrates the support ring 4; by adopting After using this structure, under the action of the plug-in part on the support ring, the outer peripheral wall of the plug-in part fits with the inner side wall of the outer edge of the annular groove, so that the support ring can support and limit the sealing ring. Through the setting of the vent hole, when compressed air enters the interior of the valve body, the compressed air can flow through the vent hole and squeeze the annular expansion part to deform the annular expansion part. Then the compressed air can enter the annular groove through the gap between the annular expansion part and the plug-in part. At the same time, the compressed air can also enter the annular groove through the gap between the piston rod and the inner peripheral wall of the support ring.

[0022] An annular step 11 is provided on the inner circumferential wall of the upper end of the valve body 1, and the upper end of the sealing ring 3 abuts against the annular step 11; by adopting this structure, after the upper end of the sealing ring abuts against the annular step, and under the action of the outer circumferential wall of the plug-in portion and the inner side wall of the outer edge of the annular groove being in contact with each other, the axial limitation of the sealing ring can be achieved, that is, the sealing ring can be reliably axially limited inside the valve body; in addition, when the air pressure inside the valve body increases, the piston rod can move upward relative to the valve body. At the same time, under the action of the upper end of the sealing ring abutting against the annular step, the sealing ring can be prevented from moving upward relative to the valve body with the piston rod; when the air pressure inside the valve body decreases, the piston rod can move downward relative to the valve body. At the same time, under the action of the outer circumferential wall of the plug-in portion and the inner side wall of the outer edge of the annular groove being in contact with each other, the support ring can limit the sealing ring from moving downward relative to the piston rod, that is, the axial limitation of the sealing ring is achieved.

[0023] An annular rib 44 is provided on the outer circumferential wall of the support ring 4, and an annular embedding groove 12 is provided on the inner circumferential wall of the valve body 1. The annular rib 44 is embedded in the annular embedding groove 12. By adopting this structure, after the annular rib is embedded in the annular embedding groove, the support ring can be reliably assembled with the valve body and achieve the purpose of axial limitation.

[0024] After the present invention adopts the above-mentioned structure, when the air pressure inside the valve body increases, a part of the compressed air can flow through the vent hole and squeeze the annular expansion part to cause the annular expansion part to deform, and the compressed air can enter the annular groove through the gap between the annular expansion part and the plug-in part. At the same time, another part of the compressed air can enter the annular groove through the gap between the piston rod and the inner circumferential wall of the support ring. After the compressed air enters the annular groove, the compressed air can squeeze the first annular contraction part, so that the first annular contraction part can be further tightly sealed with the outer wall of the piston rod. At the same time, the compressed air can squeeze the annular expansion part, so that the annular expansion part can be further tightly sealed with the inner wall of the valve body; that is, by adopting the above-mentioned structure, when the air pressure inside the valve body increases, the sealing effect of the sealing ring on the gap between the piston rod and the valve body can be further improved to avoid air leakage between the piston rod and the valve body, that is, the sealing reliability of the sealing ring on the gap between the piston rod and the valve body can be improved.

[0025] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A gas valve piston rod sealing structure, comprising a valve body (1), a piston rod (2) and a sealing ring (3); the sealing ring (3) is embedded in the inner side of the upper end of the valve body (1) and is axially limited with the valve body (1); the piston rod (2) is axially movable and penetrates the valve body (1) and the sealing ring (3); the characteristics are: The lower end of the sealing ring (3) is provided with an annular groove (31) with a bottom opening, and the inner side of the annular groove (31) forms a first annular contraction portion (32) that gradually contracts inward from top to bottom, and the first annular contraction portion (32) is tightly sealed with the outer peripheral wall of the piston rod (2), and the outer side of the annular groove (31) forms an annular expansion portion (33) that gradually expands outward from top to bottom, and the annular expansion portion (33) is interference-fitted with the inner side wall of the valve body (1) and tightly sealed.

2. The valve piston rod sealing structure according to claim 1, characterized in that: A second annular contraction portion (34) that gradually contracts inwards from bottom to top is provided at the inner edge of the upper end of the sealing ring (3), and the second annular contraction portion (34) is tightly sealed against the outer peripheral wall of the piston rod (2).

3. The valve piston rod sealing structure according to claim 2, characterized in that: The inner peripheral wall of the sealing ring (3) is connected to the inner peripheral wall of the first annular contraction portion (32) and the inner peripheral wall of the second annular contraction portion (34) to form an annular concave cavity (35).

4. The valve piston rod sealing structure according to claim 3, characterized in that: The annular cavity (35) forms an olive-shaped structure along its axial direction, with a larger inner diameter in the middle and smaller inner diameters at both ends.

5. The valve piston rod sealing structure according to any one of claims 1 to 4, characterized in that: The valve piston rod sealing structure further comprises a support ring (4); the support ring (4) is embedded in the valve body (1) below the sealing ring (3) and is axially limited with the valve body (1), and the piston rod (2) is movably inserted into the support ring (4); an annular recess (41) is provided at the upper end of the support ring (4) and in the middle of the support ring (4) in the radial direction, and the support ring (4) located inside the annular recess (41) forms a ring-shaped plug-in portion (42), the outer peripheral wall of the plug-in portion (42) is in contact with the inner side wall of the outer edge of the annular groove (31), and a plurality of vent holes (43) are provided at the bottom of the annular recess (41) and are distributed at intervals in the circumferential direction, and each of the vent holes (43) axially penetrates the support ring (4).

6. The valve piston rod sealing structure according to claim 5, characterized in that: An annular step (11) is provided on the inner peripheral wall of the upper end of the valve body (1), and the upper end of the sealing ring (3) abuts against the annular step (11).

7. The valve piston rod sealing structure according to claim 5, characterized in that: An annular convex rib (44) is provided on the outer peripheral wall of the support ring (4), and an annular embedding groove (12) is provided on the inner peripheral wall of the valve body (1), and the annular convex rib (44) is embedded in the annular embedding groove (12).

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