JP5153897B2 - Seal member - Google Patents

Description

  The present invention relates to a sealing member for a sealing device used in industrial machines and other machines.

  For example, the hydraulic shock absorber disclosed in Patent Document 1 is provided with a seal member for maintaining oil tightness inside the cylinder at the cylinder opening end. The seal member is formed by integrally molding rubber with a metal insert metal, and an oil seal part (oil side seal lip) and a dust seal part (dust side seal lip) are constituted by a rubber part including the insert metal. Has been.

  In such an insert metal / rubber integrated mold sealing member, the adhesion of rubber to the insert metal has a considerable influence on the sealing performance. In other words, if the rubber adhesion to the insert metal is low and the rubber is easy to peel off from the insert metal, the seal lip will rise when the moving parts such as the piston rod are in operation or buckle unnaturally, resulting in poor sealing performance. In addition, the expected sealing performance assumed at the time of design cannot be exhibited.

  Therefore, in order to avoid such inconvenience, a special adhesive (for example, a rubber-metal vulcanized adhesive developed for bonding rubber and metal) is applied in advance to the surface of the insert metal and bonded. A rubber material was baked and bonded to the surface of the insert metal via an agent to integrally form the insert metal and rubber (see Patent Document 2).

JP 2005-233215 (paragraphs 0025 and 0026) JP 2002-70920 (paragraph 0009)

  However, the conventional insert metal / rubber integrated mold sealing member requires processes for applying and drying the adhesive in the manufacturing process, and the existence of these processes has been a factor in increasing the manufacturing cost. . The present invention has been made in view of such circumstances.

  An object of the present invention is to provide a sealing member that can exhibit the same level of sealing performance as a conventional product using an adhesive by ensuring the adhesion between the insert member and the rubber part without using an adhesive. It is in.

The present invention relates to a seal member as an annular member, which is formed by integrally molding an insert member and a rubber portion including the insert member, and at least a part of the rubber portion functions as a seal lip.
The insert member includes a cylindrical portion (11) and an inner flange portion (12) extending radially inward from one end of the cylindrical portion. The insert member is provided with an annular recess (16) for engaging a part of the rubber part during integral molding. The annular recess (16), together with the recess (16) to have a depth or depth and non-right angle inclined with respect to the side surface of the inner flange portion of the insert member which is open (12), an annular The concave portion (16) has a depth or slope with a slope so that the bottom portion is closer to the end surface of the inner peripheral end portion of the inner flange portion (12) than the open end portion when viewed in a radial cross section. Has depth. And the adhesiveness of the said insert member and the said rubber part is improved by the anchor effect based on engagement with the cyclic | annular recessed part (16) of the said insert member, and a part of said rubber part.

  According to the seal member of the present invention, the insert member is provided with the annular recess for engaging a part of the rubber part during integral molding, and therefore the engagement between the annular recess of the insert member and a part of the rubber part. Due to the anchor effect based on the joint, the adhesion between the insert member and the rubber portion can be enhanced. Therefore, without using an adhesive in the manufacturing process as in the conventional example, ensure sufficient adhesion between the insert member and the rubber part, and exhibit and maintain the same level of sealing performance as the conventional product. Can do. In addition, by not using an adhesive, it is possible to reduce the manufacturing cost related to the adhesive, and further, it is possible to prevent contamination of the work space due to the organic solvent volatilized from the adhesive and damage to the health of the worker. it can.

  Hereinafter, reference embodiments and embodiments of the present invention will be described with reference to the drawings.

[Reference form]
As shown in FIG. 1, the seal member 1 of the reference embodiment is a generally annular member that is rotationally symmetric about a central axis C, and the insert member 10 and a rubber portion 20 that includes the insert member 10 are integrated. Molded.

  The insert member 10 includes a cylindrical portion 11 that surrounds the central axis C, and a flange-shaped inner flange portion 12 that extends radially inward from one end (right end in FIG. 1) of the cylindrical portion 11. . If the portion where the inner flange portion 12 is connected to the cylindrical portion 11 is the outer peripheral end portion of the inner flange portion 12, the inner peripheral end portion of the inner flange portion 12 located on the opposite side of the outer peripheral end portion is connected to the insert member 10. An annular engagement groove 13 is formed as a recess.

  The annular engagement groove 13 is provided so as to open to the end surface (inner peripheral side end surface) of the inner peripheral end portion of the inner flange portion 12. In addition, when the annular engagement groove 13 is viewed in the radial cross section of FIG. 1, the width of the slightly recessed portion (back portion) is slightly larger than the width of the opening end portion of the engagement groove 13. The cross-sectional shape is widened. That is, the annular engagement groove 13 is formed such that the opening end portion thereof is relatively narrow and the back portion thereof is relatively wide.

  The annular engagement groove 13 is formed by two partition walls 14 that are located on both inner sides (left and right sides in FIG. 1) of the annular engagement groove 13 at the inner peripheral end of the inner flange portion 12 of the insert member 10. It is partitioned. For this reason, these two partition walls 14 can also be grasped as convex portions provided in the insert member 10 so as to partition the annular engagement groove 13 as a concave portion.

  Further, the insert member 10 is provided with an annular groove-shaped notch 15 that is open to the inside of the cylindrical portion 11 at the boundary position between the cylindrical portion 11 and the inner flange portion 12. The annular groove-shaped notch 15 is also formed so that the opening end portion thereof is relatively narrow and the back portion thereof is relatively wide. The annular groove-shaped notch 15 is smaller than the annular engagement groove 13, but can be positioned as a second recess provided in the insert member 10.

  As shown in FIG. 1, a rubber portion 20 is integrally formed on the insert member 10 so as to include the insert member 10. This integral molding is based on so-called insert molding. The rubber part 20 is made of rubber such as NBR (nitrile butadiene rubber). In the present embodiment, no adhesive is used for bonding the insert member 10 and the rubber part 20 to each other.

  The rubber part 20 has an oil lip 21 as a first seal lip and a dust lip 22 as a second seal lip. Both the oil lip 21 and the dust lip 22 have an annular shape surrounding the central axis C. In addition, the oil lip 21 and the dust lip 22 are connected to each other at their base ends, and their tip ends protrude in substantially opposite directions along the central axis C. In the seal member 1, the insert member 10 and the rubber portion 20 are arranged so that the inner peripheral end portion of the inner flange portion 12 of the insert member 10 can be positioned in the vicinity of the connecting portion between the oil lip 21 and the dust lip 22. And are integrally molded.

  Note that both the oil lip 21 and the dust lip 22 are provided so as to be inclined with a gradient such that the distal end portion approaches the central axis C rather than the respective base end portions. Therefore, a pocket region P having a substantially triangular cross section is secured between the oil lip 21 and the dust lip 22 and inside the lips so that the inner peripheral surfaces of the lips 21 and 22 are the ceiling surfaces. ing. A garter spring G for tightening the lip 21 is mounted around the oil lip 21.

  In the seal member 1 of FIG. 1, an annular engagement groove 13 formed in the inner peripheral end face of the inner flange portion 12 of the insert member 10 and a rubber portion 20 that has entered the annular engagement groove 13 during insert molding. Some are engaged with each other. Alternatively, the two partition walls 14 provided at the inner peripheral end of the inner flange portion 12 of the insert member 10 and a part of the rubber portion 20 that has entered between the two partition walls 14 during insert molding are engaged with each other. You can also see that you are doing.

  Therefore, based on the mutual engagement between the annular engagement groove 13 (or the two partition walls 14) of the insert member 10 and a part of the rubber portion 20, the anchor effect of the rubber portion 20 with respect to the insert member 10 occurs, and adhesion Despite the fact that no agent is used, the adhesion between the insert member 10 and the rubber part 20 is ensured.

  The fact that the performance of the sealing member 1 of FIG. 1 can be compared with that of a conventional sealing member using an adhesive is proved by strength and durability tests by computer simulation.

  FIG. 4A shows a conventional seal member (conventional example) formed by bonding the insert member 10 and the rubber portion 20 using an adhesive. The insert member 10D in this conventional example is substantially the same as the insert member 10 of FIG. 1 except that the annular engagement groove 13 and the annular groove-shaped notch 15 are not provided.

  The rubber part 20D in this conventional example is substantially the same as the rubber part 20 of FIG. FIG. 4B shows a modification of the conventional example when it is assumed that the conventional example of FIG. 4A is attached to a virtual rod (shown by a broken line R), a pressure of 0.5 MPa is applied, and further time has passed. Indicates the state. In addition, although illustration of the garter spring G is abbreviate | omitted in FIG.4 (b), the deformation | transformation state in the state in which the garter spring G was mounted | worn is shown. Moreover, the phantom line in FIG.4 (b) shows a form when the sealing member of a prior art example exists in a natural state (state of non-mounting | wearing / no load) (the phantom line of FIG.5 (b) also has the same meaning).

  FIG. 5A shows a seal member (comparative example) manufactured without using any adhesive in the seal member having the same structure as the conventional example of FIG. 4A. Therefore, the insert member 10D in this comparative example is substantially the same as the insert member 10 of FIG. 1 except that the annular engagement groove 13 and the annular groove-shaped notch 15 are not provided.

  Further, the rubber part 20D in this comparative example is substantially the same as the rubber part 20 of FIG. FIG. 5B shows a modification of the comparative example when it is assumed that a comparative example of FIG. 5A is mounted on a virtual rod (shown by a broken line R), a pressure of 0.5 MPa is applied, and further time has passed. Indicates the state. In addition, although illustration of the garter spring G is abbreviate | omitted in FIG.5 (b), the deformation | transformation state in the state in which the garter spring G was mounted | worn is shown.

  On the other hand, FIG. 2 shows the seal member 1 when the seal member 1 of FIG. 1 is attached to a virtual rod (shown by a broken line R), a pressure of 0.5 MPa is applied, and it is further assumed that time has passed (reference form). ) Shows the deformation state. In addition, although illustration of the garter spring G is abbreviate | omitted in FIG. 2, the deformation | transformation state in the state in which the garter spring G was mounted | worn is shown. Moreover, the phantom line in FIG. 2 shows a form when the seal member 1 is in a natural state (non-attached / no-load state).

  From the results of the computer simulation shown in FIG. 2, FIG. 4 (b) and FIG. 5 (b), the reference form and the conventional example show superior strength and durability than the comparative example, and the reference form is the conventional example. It can be seen that the strength and durability are comparable to each other. This will be described below.

  First, according to the comparative example shown in FIG. 5B, a large gap S is formed immediately below the inner peripheral end of the inner flange portion 12 of the insert member 10D, and the inner peripheral surface of the oil lip 21 is also formed on the dust lip 22. The entire inner peripheral surface also sticks to the surface of the virtual rod R, and there is no pocket region P to be secured between the lips 21 and 22 and the surface of the virtual rod R.

  On the other hand, according to the conventional example shown in FIG. 4B, between the insert member 10D and the rubber portion 20D both directly below the inner peripheral end portion of the inner flange portion 12 of the insert member 10D and at other portions. There is no gap that suggests peeling. In addition, in FIG. 4B, although both the inner peripheral surface of the oil lip 21 and the inner peripheral surface of the dust lip 22 are strongly pressed against the surface of the virtual rod R, both the lips 21 and 22 and the virtual rod A pocket region P having a substantially triangular cross section is still secured between the surface of R.

  That is, in the conventional example, even when the pressure is applied as described above, the state in which the oil lip 21 and the dust lip 22 can exhibit their original functions as a seal lip is maintained. Thus, from the comparison between the conventional example and the comparative example, the use of the adhesive prevents the insert member 10D and the rubber portion 20D from being separated from each other, thereby ensuring the function of the seal member even at high loads. Recognize.

  On the other hand, according to the seal member 1 shown in FIG. 2, a small gap S1 is generated between the inner wall surface of the annular engagement groove 13 and a part of the rubber portion 20 that has entered the annular engagement groove. Small gaps S <b> 2 are also generated just below the partition wall 14. However, these gaps S1 and S2 are very small, and a part of the rubber portion 20 in the annular engagement groove 13 remains in the engagement groove 13 to maintain the anchor effect.

  For this reason, the base end portions of the oil lip 21 and the dust lip 22 are kept away from the surface of the virtual rod R, and the section between the lips 21 and 22 and the surface of the virtual rod R is substantially triangular. Pocket region P is secured. The state of the pocket region P in FIG. 2 is comparable to the state of the pocket region P in the conventional example of FIG.

  From these results, the sealing member 1 of the reference form is remarkably superior in terms of strength and durability as compared with the comparative example in which no adhesive is used. Moreover, the sealing member 1 of the reference form can be expected to have substantially the same strength and durability as the conventional example using an adhesive.

  Thus, according to the sealing member 1 of the reference form, the insert member 10 has an annular engaging groove 13 (or a partition wall 14 as a convex portion) as a concave portion for engaging a part of the rubber portion 20 during integral molding. Because of the anchor effect based on the mutual engagement between the annular engagement groove 13 (or the partition wall 14) of the insert member 10 and a part of the rubber portion 20, the close contact between the insert member 10 and the rubber portion 20 is provided. Can increase the sex.

  According to the reference form, sufficient adhesiveness is ensured between the insert member 10 and the rubber part 20 without using an adhesive in the manufacturing process as in the conventional example, and a sealing performance equivalent to that in the conventional example is achieved. Can be exhibited and maintained. In particular, it is possible to prevent the phenomenon (sagging) that the seal member 1 loses its shape with time and excessive deformation of the seal member 1 during use, so that the basic performance as a seal member is not impaired. Long life can be achieved.

  According to the reference mode, the manufacturing cost related to the adhesive can be reduced by not using the adhesive in the manufacturing process. Moreover, since the insert member 10 and the rubber part 20 are not bonded together with an adhesive, the insert member 10 and the rubber part 20 can be easily separated when the seal member 1 is discarded, which is advantageous in terms of resource recycling.

  According to the reference embodiment, the inner peripheral end portion of the inner flange portion 12 of the insert member 10 is located at or near the connecting portion of the oil lip 21 and the dust lip 22 in the rubber portion 20, and the annular engagement groove 13 is inserted into the insert member 10. It is provided so that it may open to the end surface of the inner peripheral end part of the member 10. Therefore, based on the mutual engagement between the annular engagement groove 13 and a part of the rubber portion 20 that has entered the annular engagement groove 13, the shape of the connecting portion of both lips 21 and 22 is more reliably maintained. Thus, it is possible to prevent as much as possible the deformation of the pocket region P secured immediately below the connecting portion between the lips 21 and 22. As a result, the oil lip 21 and the dust lip 22 can exhibit their original functions as a seal lip over a long period of time, and the durability of the seal member 1 can be at least comparable to that of the conventional example.

  According to the reference form, the annular engagement groove 13 as the recess of the insert member 10 is formed so that the opening end portion thereof is relatively narrow and the back portion thereof is relatively wide. A part of the rubber portion 20 that has entered the annular engagement groove 13 is unlikely to be detached from the engagement groove 13 even when a part of the rubber part 20 that is pulled outward from the annular engagement groove 13 is subjected to a tensile action. For this reason, in the reference form, the adhesion force of the rubber part 20 to the insert member 10 (or the ability to prevent detachment from the recess) is very high.

  According to the reference form, an annular groove-shaped notch 15 opened inside the cylindrical portion 11 is provided at a boundary position between the cylindrical portion 11 and the inner flange portion 12 of the insert member 10. This contributes to improving the adhesion between the insert member 10 and the rubber part 20. Therefore, the adhesion of the rubber part 20 to the insert member 10 can be remarkably improved by providing the annular engagement groove 13 as the first recess and the notch 15 as the second recess.

  Since the annular groove-shaped notch 15 is located at the inner corner portion of the insert member 10 formed by the cylindrical portion 11 and the inner flange portion 12, the rubber portion 20 is easily peeled off at the inner corner portion. It is very useful for prevention.

[Embodiment]
FIG. 3 shows a seal member 1A according to an embodiment of the present invention. Below, it demonstrates centering on a different point from a reference form, and abbreviate | omits description about the structure which is common in a reference form as much as possible.

  The seal member 1A in FIG. 3 is also formed by integrally molding the insert member 10A and the rubber portion 20A that includes the insert member 10A. The rubber portion 20A includes an oil lip 21 and a dust lip 22 that protrude in substantially opposite directions. The insert member 10A of FIG. 3 includes a cylindrical portion 11 and a bowl-shaped inner flange portion 12, and the inner peripheral end portion of the inner flange portion 12 is a connection between the oil lip 21 and the dust lip 22 in the rubber portion 20A. It is located near the part.

  An annular engagement groove 16 as a recess in the insert member 10 </ b> A is formed at the inner peripheral end of the inner flange portion 12. The annular engagement groove 16 is provided so as to open on the side surface of the inner peripheral end portion of the inner flange portion 12. In addition, the annular engagement groove 16 is inclined so that the bottom portion is closer to the end surface of the inner peripheral end portion of the inner flange portion 12 than the opening end portion when viewed in the radial cross section of FIG. It has a depth or depth with That is, the annular engagement groove 16 as a recess is inclined non-perpendicularly with respect to the surface (in this case, the side surface) of the inner peripheral end portion of the inner flange portion 12 of the insert member 10A where the engagement groove 16 is open. Have a certain depth or depth.

  Since the annular engagement groove 16 has an inclined depth or depth as described above, the seal member 1A is located relative to the base end portions of the oil lip 21 and the dust lip 22 (that is, the connecting portion between the lips 21 and 22). Even when a tensile action (downward tensile action in FIG. 3) acting toward the center of the rubber part 20 </ b> A is exerted, a part of the rubber portion 20 </ b> A entering the annular engagement groove 16 is not easily detached from the engagement groove 16. . In other words, the rubber part 20 </ b> A is easily caught on the annular engagement groove 16. Therefore, the adhesiveness between the insert member 10A and the rubber portion 20A is particularly enhanced near the inner peripheral end of the inner flange portion 12.

  According to FIG. 3, the annular engagement groove 16 is defined by an end partition wall 17 located at the inner peripheral end of the inner flange portion 12 of the insert member 10 </ b> A and located immediately below the engagement groove 16. . For this reason, this edge part partition wall 17 can also be grasped | ascertained as the convex part provided in the insert member 10 so that the annular engagement groove | channel 16 as a recessed part may be defined.

  Further, the insert member 10A of FIG. 3 is provided with an annular groove-shaped notch 15 that opens to the inside of the cylindrical portion 11 at the boundary position between the cylindrical portion 11 and the inner flange portion 12 in the same manner as the reference embodiment. ing.

  Thus, according to the seal member 1A of the present embodiment, the insert member 10A has an annular engagement groove 16 (or an end section as a convex portion) as a concave portion that engages a part of the rubber portion 20A during integral molding. Since the wall 17) is provided, the insert member 10A and the rubber are caused by an anchor effect based on the mutual engagement between the annular engagement groove 16 (or the end partition wall 17) of the insert member 10A and a part of the rubber portion 20A. Adhesion with the part 20A can be enhanced. Therefore, 1 A of sealing members of this embodiment can have an effect | action and effect similar to the sealing member 1 of a reference form.

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[Example of change]
In the reference form of FIG. 1, the annular engagement groove 13 as a recess is formed in the end surface of the inner peripheral end portion of the inner flange portion 12 of the insert member 10, but instead, a similar annular engagement groove 13 is formed. You may form so that it may open to the side surface of the inner peripheral edge part of the inner side flange part 12. FIG.

  In the above embodiments and modifications, the seal member is of a type having two seal lips 21 and 22. However, the application object of the present invention is not limited to this, and there is only one seal lip. The present invention may be applied to this type of seal member.

  The sealing member of the present invention is used as a component part of a sealing device used in, for example, a hydraulic shock absorber, a gas spring, various cylinder devices, and the like.

Sectional drawing of the radial direction of the sealing member according to a reference form. The schematic sectional drawing which shows the deformation | transformation state in the intensity | strength and durability test of the sealing member of FIG. Sectional drawing of the radial direction of the sealing member according to embodiment. (A) is sectional drawing of the radial direction of the sealing member (adhesive use) which is a prior art example, (b) is a schematic sectional drawing which shows the deformation | transformation state in the intensity | strength and durability test of the sealing member. (A) is sectional drawing of the radial direction of the sealing member (adhesive non-use) which is a comparative example, (b) is a schematic sectional drawing which shows the deformation | transformation state in the intensity | strength and durability test of the sealing member.

DESCRIPTION OF SYMBOLS 1,1A ... Seal member 10, 10A ... Insert member 11 ... Cylindrical part 12 ... Inner flange part 13 ... Annular engagement groove (concave part)
14 ... Two partition walls (convex)
15 ... Notch 16 in annular groove shape ... Annular engagement groove (recess)
17 ... End partition wall (convex part)
20, 20A ... rubber part 21 ... oil lip (first seal lip)
22 ... Dustrip (second seal lip)

Claims (3)

An insert member and a rubber part including the insert member are integrally molded, and at least a part of the rubber part functions as a seal lip, and is a seal member as an annular member,
The insert member includes a cylindrical portion (11) and an inner flange portion (12) extending radially inward from one end of the cylindrical portion,
Wherein the insert member, is provided an annular recess to engage a portion of the rubber portion during the integral molding (16), said annular recess (16), said insert its recess (16) is opened inner flange of the member as well as have a depth or depth and non-right angle inclined to the side of (12), said annular recess (16), when viewed in radial section, than its open end The bottom portion has a depth or depth having an inclined gradient such that the inner flange portion (12) is closer to the end surface of the inner peripheral end portion,
A seal member characterized in that the adhesion between the insert member and the rubber portion is enhanced by an anchor effect based on the engagement between the annular recess (16) of the insert member and a part of the rubber portion. The rubber part includes first and second seal lips (21, 22) projecting in substantially opposite directions;
The insert member is integrally formed with the rubber portion so that the inner peripheral end portion of the inner flange portion (12) is positioned at or near the connecting portion of the first and second seal lips in the rubber portion. The seal member according to claim 1 . An annular groove-shaped notch (15) opened inside the cylindrical portion is provided at a boundary position between the cylindrical portion (11) and the inner flange portion (12) of the insert member. The seal member according to claim 1 or 2 .

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