Gasket

Abstract

To provide a gasket capable of solving various problems, such as an increase in a size of a molding facility and securing a mold storage space.SOLUTION: In a gasket 1 that is used by incorporating a gasket body 3 comprising an endless strap-shaped elastic body into a recessed groove of a sealing part, the gasket body 3 includes a slit-shaped inner region 5 between parallel two components 3a, 3b, and is molded to have a wound shape in which the inner region 5 forms a spiral shape in the length direction. The molded gasket body 3 is incorporated into the recessed groove by largely expanding and deploying the inner region 5. The molded gasket body 3 has inversion parts 7a, 7b at end parts thereof, and is incorporated by using the inversion parts as starting points when incorporated into the recessed groove.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a gasket that is incorporated into a location where sealing (airtightness / liquidtightness) is required. [Background technology]

[0002] For example, in the case of a pneumatic actuator, a gasket made of an elastic material is installed between the housing and the cover to improve sealing performance. Various gaskets are also installed in joint areas of various pipes, or between the carburetor and float chamber of a motorcycle.

[0003] Patent Document 1 discloses an example in which an elastic ring-shaped gasket is used in an annular recess provided on the joint surface of a pipe. Patent Document 2 proposes a gasket for use in pressure equipment such as pneumatic and hydraulic actuators.

[0004] Generally, this type of elastic gasket is formed in a ring shape with a size (perimeter) corresponding to the sealing part to be installed. In other words, if the sealing area is large, a large-sized gasket is prepared to accommodate it.

[0005] Such gaskets are usually formed using a mold. Therefore, molding a large gasket requires a correspondingly large mold, which can lead to various issues, such as increasing the size of the molding equipment and securing space to store the molds. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Utility Model Registration No. 3104291 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-329400 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made to solve these problems, and its object is to provide a gasket that can solve various problems such as the increase in size of molding equipment and the need to secure mold storage space. [Means for solving the problem]

[0008] In order to achieve the above object, the first invention is a gasket in which a gasket body made of an endless string-like elastic body is fitted into a recessed groove of a sealing part, The gasket body has a slit-shaped inner region between two parallel lines, and the inner region is formed into a spiral shape in the longitudinal direction, The molded gasket body is expanded so that its inner region is widened and fitted into the recessed groove.

[0009] The second aspect of the present invention is a gasket in which a gasket body made of an endless string-like elastic body is fitted into a recessed groove of a sealing part, The gasket body has a slit-shaped inner region between two parallel lines, and the inner region is molded into a shape having a spiral portion wound in a longitudinal direction so as to form a spiral shape in a part thereof, The molded gasket body is expanded so that its inner region is widened and fitted into the recessed groove.

[0010] The third present invention is the first or second present invention, wherein the gasket body is molded so that the inner region thereof has a width greater than the wire diameter of the gasket body.

[0011] The fourth invention is the first invention or the second invention, wherein the molded gasket body has an inverted portion at its end, and when the gasket body is fitted into the groove, the inverted portion is used as the starting point for fitting. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a gasket that can solve various problems such as the need for larger molding equipment and the need to secure mold storage space. [Brief explanation of the drawings]

[0013] [Figure 1] 1A is a plan view showing a gasket according to a first embodiment of the present invention, and FIG. 1B is an enlarged cross-sectional view of a main part thereof. [Figure 2] FIG. 2 is a plan view showing the gasket of FIG. 1 in an unfolded state. [Figure 3] FIG. 10 is a perspective view of the state in which the unfolded gasket is being fitted into the recessed groove. [Figure 4] FIG. 10 is a plan view illustrating the assembly of the gasket. [Figure 5] FIG. 4 is a partially enlarged cross-sectional view showing the state in which the gasket is installed in the sealing portion. [Figure 6] FIG. 4 is a plan view showing a gasket according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a plan view showing a gasket according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. It should be noted that this embodiment is merely an example of the present invention and is not to be construed as being limited thereto in any way, and that design modifications are possible within the scope of the present invention.

[0015] A first embodiment of the present invention is shown in FIGS. As shown in Figures 3 and 5, in this embodiment, as an example, a sealing portion is assumed to be between a rectangular housing (lower member) 100 and a lid body 200 (upper member) of a square actuator, and a gasket 1 is incorporated to improve the sealing performance of this sealing portion.

[0016] The gasket 1 has an endless string-like (ring-shaped) gasket body 3. The gasket body 3 is made of an elastic material such as synthetic rubber, and is used by being fitted into a recessed groove 101 formed in a housing 100. The recessed groove 101 is formed to surround the internal space (sealed area) 100a of the housing 100, and by fitting the gasket body 3 into this recessed groove 101 and placing the lid body 200 on the housing 100, the internal space 100a of the housing 100 is sealed.

[0017] The gasket body 3 has a circumferential length corresponding to the groove 101, and when molding this using a mold, a large mold has traditionally been required, but the present invention employs a unique molding shape to enable the mold to be made smaller.

[0018] In the gasket 1 of this embodiment, when an endless string-like gasket body 3 made of an elastic material such as synthetic rubber is molded in a mold, it is molded into a spiral wound shape in a plan view as shown in Fig. 1(A) . That is, the endless string-like gasket body 3 has a slit-like inner region 5 between two parallel strings 3a and 3b, and is molded into a circular wound shape with a predetermined width W so that the inner region 5 has a slit-like spiral shape in the longitudinal direction. In this case, as shown in FIG. 1(B), the gasket body 3 is molded so that the inner region 5 between the two parallel wires 3a and 3b has a width W1 larger than the wire diameter d of the gasket body 3. Although the wound shape of the gasket body 3 is shown as a circular spiral in this embodiment, a polygonal spiral shape is also included in the present invention. The number of turns in the spiral is not limited to this embodiment and can be changed within the scope of the present invention.

[0019] Then, the gasket body 3 molded into such a spiral wound shape is expanded so that its inner region 5 is widely spread (see FIG. 2), and is then fitted into the recessed groove 101 of the housing 100 (see FIG. 3). That is, in the gasket 1 according to the present invention, the gasket body 3 is formed into a small spiral wound shape relative to the circumferential length of the groove 101, and when in use, it is expanded to fit into the groove 101. In this case, since the gasket body 3 is an elastic body, it can be expanded into any shape, and therefore it can be easily expanded into a shape corresponding to the groove 101 and fitted into the groove 101.

[0020] The gasket body 3 has a substantially uniform cross-sectional shape around its entire periphery, and in this embodiment, is formed to have a circular cross-sectional shape (see FIG. 5). Although a circular cross-sectional shape is preferred, the cross-sectional shape is not particularly limited in the present invention as long as it does not impair sealing performance. Furthermore, the wire diameter d of the gasket body 3 is molded to be larger than the depth of the groove 101 of the housing 100 into which the gasket body 3 is fitted. As a result, when the gasket body 3 is fitted into the groove 101 and the lid 200 is placed over the housing 100 to seal it, the gasket body 3 is crushed within the groove 101, pressing against the housing 100 and the lid 200 from the inside and reliably sealing the gap between them.

[0021] The gasket 1 of this embodiment is molded by a general molding method (compression molding, transfer molding) using a mold. The mold has a spiral cavity for molding the gasket shown in Fig. 1, and the raw rubber material is filled into the cavity and vulcanization molding is performed.

[0022] According to the present invention, when molding a gasket using this mold, the mold can be made smaller. That is, as described above, the gasket 1 according to the present invention can provide a large gasket that corresponds to the recessed groove 101 by molding the gasket body 3 into a small spiral shape and expanding it greatly during assembly, thereby eliminating the need for large molds and molding equipment. Therefore, the object of the present invention, which is to solve various problems such as the need for large molding equipment and the need to secure mold storage space, can be achieved.

[0023] Furthermore, in the gasket 1 of this embodiment, the gasket body 3 has a slit-like inner region 5 between the two parallel wires 3a and 3b in the spiral-molded state, which prevents the two parallel wires 3a and 3b from being connected by molding burrs during molding, thereby enabling stable molding. In particular, in this embodiment, the inner region 5 has a sufficient width W1 that is larger than the wire diameter d of the gasket body, which makes the above effect even more reliable.

[0024] Furthermore, the gasket 1 of this embodiment has R-shaped inverted portions 7a, 7b at both ends of the spirally molded gasket body 3 in the molded shape shown in FIG. When the gasket body 3 is expanded and fitted into the groove 101, the inverted portion functions as a starting point for fitting. That is, as shown in Fig. 4, with the gasket body 3 expanded, the position of the inverted portion 7a (or 7b) is aligned with the corner 101a of the groove 101, and then the inverted portion 7a is fitted into the corner 101a of the groove 101 so as to be hooked onto the corner 101a. Then, the gasket body 3 is fitted into the entire groove 101 using this as a starting point. By using the inverted portion as the starting point for assembly in this manner, the gasket body 3 can be assembled smoothly and accurately.

[0025] Furthermore, in this embodiment, the gasket body 3 is formed to have a circular cross section, so even if the gasket body 3 is twisted during assembly, the gasket is reliably assembled and can be in even contact with the housing 100 and the lid body 200, so sealing performance is not impaired.

[0026] Although the present embodiment shows an example of one gasket, it is also possible to mold multiple gaskets. In this case, by forming a cavity in the mold so that one spiral wound gasket is placed between the other spiral wound gaskets in parallel, multiple molding becomes possible, thereby improving the molding efficiency of the gaskets.

[0027] Another embodiment of the present invention is shown in Figures 6 and 7. Note that the same reference numerals are used to designate parts corresponding to those in the first embodiment described above, and the description thereof will be omitted.

[0028] FIG. 6 shows a second embodiment of the present invention, and the gasket 1 shown here is formed by molding the gasket body 3 into two continuous spiral shapes. That is, in this second embodiment, the gasket body 3 is composed of a first spiral portion 10A and a second spiral portion 10B, and both of these first spiral portion 10A and second spiral portion 10B are molded into a wound shape so that the slit-shaped inner region 5 forms a spiral shape in the longitudinal direction, as in the first embodiment described above, and have a shape in which these first spiral portion 10A and second spiral portion 10B are integrally connected by a connecting portion 11.

[0029] In this second embodiment, the gasket body 3 is molded so that the first spiral portion 10A and the second spiral portion 10B have opposite spiral shapes, but they may also be molded so that they are both wound in the same direction.

[0030] In this second embodiment, the slit-shaped inner region 5 communicating with the first spiral portion 10A and the second spiral portion 10B is expanded so as to be widely spread, and the gasket body 3 is incorporated into the recessed groove 101.

[0031] In this second embodiment, the molded gasket body 3 has R-shaped inversion portions 7a, 7b at the ends of the first spiral portion 10A and the second spiral portion 10B, respectively, and when assembled into the groove 101, the inversion portions are used as the starting point for assembly into the groove 101, similar to the first embodiment described above.

[0032] Figure 7 shows a third embodiment of the present invention, and the gasket 1 shown here has a spiral portion 12 molded into a part of the gasket body 3, similar to that of the first embodiment described above. That is, in this third embodiment, the gasket body 3 is composed of a spiral portion 12 and a zigzag portion 13, and here, as in the first embodiment, the spiral portion 12 is molded into a wound shape so that the slit-shaped inner region 5 forms a spiral shape in the longitudinal direction, while the zigzag portion 13 is molded into a folded shape so that the slit-shaped inner region 5 forms a zigzag fold in the longitudinal direction, and these spiral portion 12 and zigzag portion 13 have a shape in which they are connected together by a connecting portion 14.

[0033] In the third embodiment, the slit-shaped inner region 5 communicating with the spiral portion 12 and the zigzag portion 13 is expanded so as to be widely spread, and the gasket body 3 is fitted into the recessed groove 101 .

[0034] In this third embodiment, the molded gasket body 3 has R-shaped inverted portions 7a, 7b at the respective ends of the spiral portion 12 and the zigzag portion 13, and when inserted into the groove 101, it is inserted into the groove 101 starting from the inverted portion, just like the first embodiment described above.

[0035] The gaskets of the second and third embodiments described above are suitable for use in large gaskets because the gasket body 3 can be expanded to a larger extent than in the first embodiment. [Industrial Applicability]

[0036] The present invention can be used for all gaskets made of elastic material that are incorporated into joint areas of pneumatic and hydraulic actuators, various pipes, etc., or between the carburetor and float chamber of a motorcycle, etc. [Explanation of symbols]

[0037] 1 gasket 3 Gasket body 5 Inner area 7a, 7b Reversed section 100 Housing 101 Groove 200 Lid

Claims

1. A gasket is used by incorporating a gasket body made of an endless string-like elastic body into a recessed groove in a sealing part, The gasket body has a slit-shaped inner region between two parallel gaskets, and the inner region is formed into a spiral shape wound in the longitudinal direction, A gasket characterized in that the molded gasket body is expanded so as to widen the inner region and is fitted into the recessed groove.

2. A gasket is used by incorporating a gasket body made of an endless string-like elastic body into a recessed groove in a sealing part, The gasket body has a slit-shaped inner region between two parallel gaskets, and the inner region is molded into a shape having a spiral portion wound in a longitudinal direction to form a spiral shape in a part thereof, A gasket characterized in that the molded gasket body is expanded so as to widen the inner region and is fitted into the recessed groove.

3. 3. The gasket according to claim 1, wherein the gasket body is molded so that the inner region has a width greater than a wire diameter of the gasket body.

4. 3. The gasket according to claim 1, wherein the molded gasket body has an inverted portion at an end thereof, and when the gasket body is fitted into the recessed groove, the inverted portion is used as a starting point.

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