S-shaped coil spring energy storage sealing ring with constant sealing force

Abstract

The utility model provides an S-shaped coil spring energy storage sealing ring with constant sealing force, relates to the technical field of sealing rings, and aims to solve the technical problem of unstable sealing force of a spring energy storage sealing ring in the prior art. An S-shaped coil spring energy storage sealing ring with constant sealing force comprises an annular elastic sealing layer and an S-shaped coil spring embedded in the elastic sealing layer, and the S-shaped coil spring comprises a plurality of wave crest sections and wave trough sections which are alternately arranged. The vertical distance between the outer edge of the wave crest section and the outer surface of the elastic sealing layer is smaller than that between the outer edge of the wave trough section and the outer surface of the elastic sealing layer, and the elastic modulus of the S-shaped coil spring is larger than that of the elastic sealing layer.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of sealing ring, specifically refers to a constant sealing force S type coil spring energy storage sealing ring. BACKGROUND

[0002] Spring energy storage sealing ring is a common sealing mode, the existing spring energy storage sealing ring, such as V type or H type spring structure, has the following defects: the sealing force increases suddenly when the compression amount increases, the friction force rises, the sealing surface wears out, when the compression amount is too large, the spring is permanently deformed due to excessive deformation of the sealing element, and the sealing is invalid;The size of the sealing ring in the precision instrument is fine and the material is soft, the sealing ring needs to be put into the cavity groove first during installation, and then inserted into the shaft body, in this process, the sealing ring is easy to fall off from the groove, or damaged by the shaft end, resulting in incomplete sealing. SUMMARY

[0003] In view of the defects of the prior art, the utility model aims at providing a constant sealing force S type coil spring energy storage sealing ring to solve the technical problem of unstable sealing force of the spring energy storage sealing ring in the prior art.

[0004] To solve the above technical problems, the utility model provides a constant sealing force S type coil spring energy storage sealing ring, which comprises an annular elastic sealing layer and an S type coil spring embedded in the elastic sealing layer, the S type coil spring comprises a plurality of alternating wave crest segments and wave trough segments, the vertical distance between the outer edge of the wave crest segment and the outer surface of the elastic sealing layer is less than the vertical distance between the outer edge of the wave trough segment and the outer surface of the elastic sealing layer, and the elastic modulus of the S type coil spring is greater than the elastic modulus of the elastic sealing layer.

[0005] After adopting the above structure, the utility model has the following advantages: the sinusoidal curve structure of the S type coil spring is compared with the traditional V type or H type spring, the stress distribution is more uniform through the continuous and alternating design of the wave shape, the sudden increase of the sealing force when the compression amount increases is prevented, the wear of the sealing surface is accelerated, and the permanent deformation of the spring caused by local stress concentration is avoided, so that stable sealing force is provided.

[0006] As an improvement, the S type coil spring further comprises an arc transition segment connected between the wave crest segment and the wave trough segment, and the curvature radius of the arc transition segment is greater than the curvature radius of the wave crest segment and the wave trough segment;By adopting this structure, the stress concentration is further reduced and the fatigue life is prolonged by setting the arc transition segment.

[0007] As an improvement, the axial end face of the elastic sealing layer is provided with an annular protrusion, and the annular protrusion is used for interference fit with the cavity groove;By adopting this structure, the sealing ring is prevented from falling off from the cavity groove and causing incomplete sealing when inserted into the shaft body by interference fit of the annular protrusion and the cavity groove.

[0008] As an improvement, the inner diameter of the annular protrusion is larger than the inner diameter of the elastic sealing layer, and the outer diameter of the annular protrusion is smaller than the outer diameter of the elastic sealing layer; with this structure, the sealing ring is convenient to install, and contact between the shaft body and the annular protrusion is avoided.

[0009] As an improvement, the inner surface of the elastic sealing layer is provided with a plurality of compensation grooves distributed in the circumferential direction and extending in the circumferential direction, and the compensation grooves are arranged in the radial direction corresponding to the trough sections of the S-shaped coil spring; with this structure, the compensation grooves provide directional deformation space for the compression deformation of the elastic sealing layer, and stress concentration is avoided.

[0010] As an improvement, the cross section of the compensation groove is in a trapezoidal structure, and the opening width is larger than the groove bottom width; with this structure, a progressive deformation guide is formed, and the deformation uniformity of the elastic sealing layer is improved.

[0011] As an improvement, a temperature compensation layer is coated on the outer peripheral surface of the elastic sealing layer, and the thermal expansion coefficient of the temperature compensation layer is between the elastic sealing layer and the S-shaped coil spring; with this structure, the thermal expansion coefficient of the temperature compensation layer is between the elastic sealing layer and the S-shaped coil spring, a stepped thermal expansion gradient is formed, and when the environmental temperature changes: the expansion / contraction amount of the temperature compensation layer is between the elastic sealing layer and the S-shaped coil spring, which can progressively offset or reduce the internal stress generated by the difference in thermal expansion of the two.

[0012] As an improvement, the elastic sealing layer includes a first elastic layer and a second elastic layer stacked in the radial direction from inside to outside, and the elastic modulus of the first elastic layer is smaller than that of the second elastic layer; with this structure, the first elastic layer dominates the deformation under low pressure, and the high flexibility is used to fit the sealing interface, realizing effective sealing under low pressure, and the second elastic layer is involved under high pressure, providing rigid support to prevent the elastic sealing layer from being deformed excessively and failing due to excessive system pressure. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a structural schematic view of the utility model.

[0014] Figure 2 It is a sectional view of the utility model.

[0015] Figure 3 It is a structural schematic view of the utility model when installed in the cavity groove.

[0016] Reference signs: 1, elastic sealing layer; 11, first elastic layer; 12, second elastic layer; 2, S-shaped coil spring; 21, peak section; 22, trough section; 23, arc transition section; 3, annular protrusion; 4, compensation groove; 5, temperature compensation layer. DETAILED DESCRIPTION

[0017] The utility model discloses a constant sealing force S-shaped coil spring energy storage sealing ring.

[0018] As Figures 1 to 3 The utility model discloses a constant sealing force S-shaped coil spring energy storage sealing ring, including annular elastic sealing layer 1 and the S-shaped coil spring 2 of embedding in elastic sealing layer 1, the S-shaped coil spring 2 includes a plurality of alternately arranged wave crest section 21 and wave trough section 22, and the vertical distance of wave crest section 21 outer edge and the outer surface of elastic sealing layer 1 is less than the vertical distance of wave trough section 22 outer edge and the outer surface of elastic sealing layer 1, and the elastic modulus of S-shaped coil spring 2 is greater than the elastic modulus of elastic sealing layer 1.

[0019] The sinusoidal curve structure of S-shaped coil spring 2 is compared with traditional V-shaped or H-shaped spring, and the wave crest section 21 provides initial pre-tightening force by the continuous alternation design of wave shape, and the wave trough section 22 gradually releases the resilience when being compressed, realizes the self-adaptive regulation of sealing force, makes stress distribution more uniform, prevents the sudden increase of sealing force when the compression amount increases and accelerates the wear of sealing surface, and simultaneously avoids the permanent deformation of spring caused by local stress concentration, thereby providing stable sealing force.

[0020] As Figure 1 The S-shaped coil spring 2 further includes the arc transition section 23 connected between the wave crest section 21 and the wave trough section 22, and the curvature radius of the arc transition section 23 is greater than the curvature radius of the wave crest section 21 and the wave trough section 22, further reduces stress concentration, and prolongs fatigue life.

[0021] As Figure 1 The inner surface of the elastic sealing layer 1 is provided with a plurality of compensation grooves 4 distributed along the circumference and extending along the circumference, the compensation grooves 4 are arranged in the radial direction corresponding to the wave trough section 22 of the S-shaped coil spring 2, the cross section of the compensation groove 4 is in trapezoidal structure, the opening width is greater than the groove bottom width, the compensation groove 4 provides directional deformation space for the compression deformation of the elastic sealing layer 1, avoids stress concentration, the trapezoidal structure compensation groove 4 forms progressive deformation guide, and improves the deformation uniformity of the elastic sealing layer 1.

[0022] As Figure 1 And Figure 2As shown, a temperature compensation layer 5 is wrapped around the outer periphery of the elastic sealing layer 1. The coefficient of thermal expansion of the temperature compensation layer 5 is between that of the elastic sealing layer 1 and the S-shaped coil spring 2, forming a stepped thermal expansion gradient. When the ambient temperature changes, the expansion / contraction of the temperature compensation layer 5 is between that of the elastic sealing layer 1 and the S-shaped coil spring 2, which can gradually offset or reduce the internal stress caused by the difference in thermal expansion between the two. For example, in a high-temperature environment, the expansion of the elastic sealing layer 1 is greater than that of the temperature compensation layer 5, which is greater than that of the S-shaped coil spring 2. The temperature compensation layer 5 absorbs the deformation difference between the elastic sealing layer 1 and the S-shaped coil spring 2 through its own expansion deformation, thus avoiding stress concentration. Moreover, when external temperature fluctuations are transmitted to the elastic sealing layer 1 through the temperature compensation layer 5, its heat conduction rate is adjusted due to the difference in material properties, reducing the instantaneous temperature difference between the elastic sealing layer 1 and the S-shaped coil spring 2, and reducing the sudden deformation caused by thermal shock.

[0023] In this embodiment, the elastic sealing layer 1 is made of fluororubber, the temperature compensation layer 5 is made of carbon fiber reinforced polytetrafluoroethylene, and the S-shaped coil spring 2 is made of stainless steel.

[0024] like Figure 1 As shown, the elastic sealing layer 1 includes a first elastic layer 11 and a second elastic layer 12 stacked sequentially from the inside to the outside in the radial direction. The elastic modulus of the first elastic layer 11 is less than that of the second elastic layer 12. Under low-pressure conditions, the first elastic layer 11 dominates the deformation and uses its high flexibility to fit the sealing interface to achieve effective sealing under low pressure. Under high-pressure conditions, the second elastic layer 12 intervenes to provide rigid support and prevent the elastic sealing layer 1 from excessively deforming and failing due to excessive system pressure.

[0025] like Figure 2 As shown, an annular protrusion 3 is provided on the axial end face of the elastic sealing layer 1. The annular protrusion 3 is used for interference fit with the cavity groove. The inner diameter of the annular protrusion 3 is larger than the inner diameter of the elastic sealing layer 1, and the outer diameter of the annular protrusion 3 is smaller than the outer diameter of the elastic sealing layer 1.

[0026] like Figure 3 As shown, a first mounting groove for installing the elastic sealing layer 1 and a second mounting groove for installing the annular protrusion 3 are provided in the cavity groove. The second mounting groove is located on the upper wall of the first mounting groove. When this utility model is installed in the cavity groove, the annular protrusion 3 will not contact the first mounting groove, thus avoiding the increased installation difficulty caused by the interference fit between the annular protrusion 3 and the first mounting groove.

[0027] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above-described embodiment. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

Claims

1. A constant force S-shaped coil spring energized seal ring characterized by, The sealing layer (1) is annular, and the S-shaped coil spring (2) is embedded in the sealing layer (1), the S-shaped coil spring (2) comprises a plurality of alternating peak segments (21) and valley segments (22), the vertical distance between the outer edge of the peak segment (21) and the outer surface of the sealing layer (1) is less than the vertical distance between the outer edge of the valley segment (22) and the outer surface of the sealing layer (1), and the elastic modulus of the S-shaped coil spring (2) is greater than the elastic modulus of the sealing layer (1).

2. The constant force S-spring seal of claim 1, wherein, The S-shaped coil spring (2) further comprises an arc-shaped transition segment (23) connected between the peak segment (21) and the valley segment (22), and the curvature radius of the arc-shaped transition segment (23) is greater than the curvature radius of the peak segment (21) and the valley segment (22).

3. The constant force S-spring seal of claim 1, wherein, The axial end surface of the sealing layer (1) is provided with an annular protrusion (3), and the annular protrusion (3) is used for interference fit with the cavity groove.

4. The constant force S-spring seal of claim 3, wherein, The inner diameter of the annular protrusion (3) is greater than the inner diameter of the sealing layer (1), and the outer diameter of the annular protrusion (3) is less than the outer diameter of the sealing layer (1).

5. The constant force S-spring seal of claim 1, wherein, The inner surface of the sealing layer (1) is provided with a plurality of compensation grooves (4) distributed and extending in the circumferential direction, and the compensation grooves (4) are arranged in the radial direction corresponding to the valley segments (22) of the S-shaped coil spring (2).

6. The constant force S-spring seal of claim 5, wherein, The cross section of the compensation groove (4) is in a trapezoidal structure, and the opening width is greater than the groove bottom width.

7. The constant force S-spring seal of claim 1, wherein, The outer circumferential surface of the sealing layer (1) is coated with a temperature compensation layer (5), and the thermal expansion coefficient of the temperature compensation layer (5) is between the sealing layer (1) and the S-shaped coil spring (2).

8. The constant force S-spring seal of claim 1, wherein, The sealing layer (1) comprises a first elastic layer (11) and a second elastic layer (12) stacked in the radial direction from inside to outside, and the elastic modulus of the first elastic layer (11) is less than the elastic modulus of the second elastic layer (12).

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