JP2009019643A - Ring mold boot and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a metal ring hard to rust by improving waterproofing performance in a ring mold boot in which the metal ring is buried in an elastic body. <P>SOLUTION: In the ring mold boot 10, the metal ring 11 is buried in the elastic body 12. The elastic body 12 is provided with at least two annular seals 12a3 and 12a4 for preventing foreign matters such as dust and moisture from the outside from entering the inside. A cutoff 12a1 via which the metal ring 11 is partially exposed is formed on the inner side than the annular seals 12a3 and 12a4. The foreign matters such as dust and moisture from the outside hardly enter a portion in which the cutoff 12a1 is formed, so that waterproofing performance can be improved, and the metal ring 11 can be made hard to rust. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a ring mold type boot in which a metal ring is embedded in an elastic body and a manufacturing method thereof.

A ring mold type boot in which a metal ring is embedded in an elastic body and a manufacturing method thereof are disclosed in, for example, Patent Document 1 below. In the ring mold type boot shown in the following Patent Document 1, the elastic body has at least two annular seal portions for preventing foreign matters such as dust and moisture from entering the inside. In the annular band region sandwiched between both sides by two annular seal portions, a notch for partially exposing the metal ring is formed. Moreover, the manufacturing method of the ring mold type | mold boot shown by the following patent document 1 arrange | positions a metal ring in the cavity formed with a shaping | molding die, and inject | pours the molten elastic material in the said cavity, A method of manufacturing a ring mold type boot in which a metal ring is embedded in an elastic body, wherein when the metal ring is arranged in the cavity, one end face in the axial direction of the metal ring and a radially outer peripheral face (or The metal ring is arranged in the cavity in a state where the metal ring is positioned on the molding die via a plurality of support portions that are in contact with the radially inner peripheral surface.
JP 2002-327849 A

  In the ring mold type boot described in Patent Document 1 described above, a cutout in which the metal ring is partially exposed is formed in the elastic body in the annular band region sandwiched between both sides by two annular seal portions. The metal ring is not directly exposed to the outside air, and the metal ring is prevented from being rusted. However, in this ring mold type boot, foreign matters such as dust and moisture from the outside may enter the annular band region sandwiched between the two sides by the two annular seal portions, and improvement in waterproofness is desired. .

  Moreover, in the manufacturing method of the ring mold type | mold boot described in the above-mentioned patent document 1, the several support part for positioning a metal ring to a shaping | molding die is provided in the cavity for forming two annular seal parts. The shape of each support portion is restricted by the shape of the two annular seal portions. For this reason, each support portion supports the metal ring at the step formed at the tip thereof, and the assembling property when the metal ring is assembled to a plurality of support portions is poor, resulting in a decrease in productivity. In addition, there is a risk of assembly failure, and there is a concern about deterioration in quality, yield deterioration, and the like.

  The present invention has been made to solve the above-described problems, and in a ring mold type boot in which a metal ring is embedded in an elastic body, foreign substances such as dust and moisture from the outside enter the elastic body. It is characterized in that at least two annular seal portions for preventing the metal ring are provided, and a notch for partially exposing the metal ring is formed inside these annular seal portions.

  In the ring mold type boot according to the present invention, notches in which the metal ring is partially exposed are formed inside all the annular seal portions provided in the boot. For this reason, it is difficult for foreign matter such as dust and moisture from the outside to enter the part where the notch is formed, and the metal ring is partially exposed in the annular band region sandwiched on both sides by the two annular seal portions. Compared with the case where the notch to be formed is formed in the elastic body, it is possible to improve the waterproof property, and it is possible to make the metal ring difficult to rust.

  The present invention also provides a ring mold type boot for manufacturing a boot in which the metal ring is embedded by disposing a metal ring in a cavity formed by a mold and injecting a molten elastic material into the cavity. In the manufacturing method, when the metal ring is disposed in the cavity, a tapered guide portion that coaxially guides the metal ring with respect to the cavity, and when the metal ring is disposed in the cavity The metal ring is positioned on the mold through a plurality of support jigs provided with receiving portions for receiving the metal ring in contact with the axially one side end surface and the radial inner peripheral surface of the metal ring. In the state, it is characterized by being disposed in the cavity.

  In the method of manufacturing a ring mold type boot according to the present invention, notches in which the metal rings are partially exposed are formed inside all the annular seal portions provided in the boot, and the shape of the notches is on the innermost side. Only the shape of the annular seal portion to be formed is restricted. For this reason, compared to the shape of the notch being constrained by the shape of the two annular seals, the design flexibility of the shape of the notch is increased, and the shape of each support jig that becomes the shape of the notch is produced, quality, It is possible to make the shape excellent in terms of efficiency.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show an embodiment of a ring mold type boot and a manufacturing method thereof according to the present invention. The ring mold type boot 10 of this embodiment is a movable caliper type for a vehicle as shown in FIG. It is a dust boot disposed between the piston 20 of the disc brake device and the cylinder body 30 of the caliper. The piston 20 is fitted in the cylinder hole 31 of the cylinder body 30 so as to be slidable in the axial direction, and the piston 20 is connected to the cylinder body 30 on the inner side (not shown) when braking is released. A piston seal 40 that returns a predetermined amount toward the right) is interposed.

  The boot 10 is formed into a ring shape as a whole by the metal ring 11 and the elastic body 12, and is assembled by fitting into an annular groove 21 having a rectangular cross section formed on the outer periphery of the piston 20 at the inner peripheral end portion 10a. The end 10b is assembled to the annular opening step 32 of the cylinder body 30 by fitting to prevent foreign matters such as dust and moisture from entering the sliding portion of the cylinder hole 31 and the piston 20. .

  The metal ring 11 is formed in an annular shape with a metal material inevitable to rust, has a rectangular cross-sectional shape, is embedded in the elastic body 12, and a part thereof is partially formed by a notch 12 a 1 formed in the elastic body 12. Is exposed. The elastic body 12 includes an annular outer peripheral portion 12a fitted to the annular opening step 32 of the cylinder body 30, an annular inner peripheral portion 12b fitted to the annular groove 21 of the piston 20, and the annular outer peripheral portion 12a and the annular inner portion. It is composed of a bellows portion 12c that integrally connects the peripheral portion 12b and freely deforms to allow relative movement between the annular outer peripheral portion 12a and the annular inner peripheral portion 12b, and is made of an elastic material such as rubber. Yes. Note that the shapes of the annular inner peripheral portion 12b and the bellows portion 12c in the elastic body 12 are conventionally known shapes.

  The annular outer peripheral portion 12a of the elastic body 12 is a ring mold end portion in which a metal ring 11 is embedded as a core metal, and a plurality of (for example, six) notches 12a1 are provided in the circumferential direction on the inner peripheral side. The first annular seal portion 12a2, the second annular seal portion 12a3, and the third annular seal portion 12a4 are provided on the outer peripheral side. Each notch 12a1 is formed by the support jig 140 shown in FIGS. 3 and 4, through which a part of the end surface on one side in the axial direction and a part of the radially inner peripheral surface of the metal ring 11 are exposed. Yes.

  The first annular seal portion 12a2 is in pressure contact with the opening-side peripheral surface 32a of the annular opening step 32 in the cylinder body 30 by the elastic force of the elastic body, and foreign matter such as dust and moisture from the outside of the boot enters the boot. Is prevented. The second annular seal portion 12a3 is formed to project in an arc shape in cross section, and is in pressure contact with the inner surface 32b of the annular arc recess formed in the annular opening step portion 32 of the cylinder body 30 by the elastic force of the elastic body. This prevents foreign matter such as dust and moisture from entering the boot. The third annular seal portion 12a4 is formed in a tongue-like shape, and is in pressure contact with the corner inner surface 32c of the annular opening step 32 in the cylinder body 30 by the elastic force of the elastic body. Prevents foreign matter such as water and moisture from entering the boot.

  By the way, in this embodiment, the notch 12a1 in which the metal ring 11 is partially exposed is formed inside all the annular seal portions 12a2, 12a3, 12a4 included in the boot 10. For this reason, it is difficult for foreign matter such as dust or moisture from the outside of the boot to enter the portion where the notch 12a1 is formed, and in the annular band region sandwiched between both sides by the two annular seal portions (12a3, 12a4). Compared with the case where the cutout in which the metal ring is partially exposed is formed in the elastic body, it is possible to improve the waterproof property, and it is possible to make the metal ring 11 difficult to rust.

  Next, a method for manufacturing the boot 10 will be described with reference to FIGS. FIG. 3 shows a mold 100 used in the method for manufacturing the boot 10 described above. The mold 100 includes a lower mold 110, an upper mold 120, and an intermediate mold 130, and the lower mold 110 includes a plurality of supporting jigs. Tools 140 are fixed at equal intervals in the circumferential direction. The lower mold 110, the upper mold 120, and the middle mold 130 form a cavity S having the same shape as the outer shape of the boot 10 in the natural state (free state) shown in FIG. 2 in the combined state (the state shown in FIG. 3). It has a molding surface that can be joined and separated. The upper mold 120 is provided with a plurality of injection ports 121 for injecting a molten elastic material into the cavity S.

  As shown in detail in FIG. 4, each support jig 140 is arranged when the metal ring 11 is disposed in the cavity S (at this time, the upper mold 120 is removed from the lower mold 110 and the middle mold 130). In addition, a tapered guide portion 141 that guides the metal ring 11 coaxially with respect to the cavity S, and when the metal ring 11 is disposed in the cavity S, one end surface in the axial direction of the metal ring 11 and the inside of the radial direction. A receiving portion (step portion) 142 that receives the metal ring 11 in contact with the peripheral surface is provided. The diameter of the imaginary circle connecting the tips of the guide portions 141 of the support jigs 140 is set smaller than the inner diameter of the metal ring 11, and the metal ring 11 can be easily placed at a predetermined position in the cavity S by the guide portions 141. It is possible to set. For this reason, the metal ring 11 is disposed in the cavity S in a state where the metal ring 11 is positioned on the mold 100 via the plurality of support jigs 140.

  After the metal ring 11 is disposed in the cavity S, the upper mold 120 is combined with the lower mold 110 and the middle mold 130. Thereafter, the molten elastic material is injected into the cavity S through the injection port 121 of the upper mold 120, and the boot 10 in which the metal ring 11 is embedded is molded. The boot 10 thus molded is removed from the lower mold 110, the upper mold 120, and the middle mold 130, and then an unnecessary portion (injection portion) is removed to finish the shape shown in FIG.

  In the manufacturing method of the boot 10 described above, the notch 12a1 in which the metal ring 11 is partially exposed is formed inside all the annular seal portions 12a2, 12a3, 12a4 provided in the boot 10, and the notch 12a1 is formed. The shape of is limited only by the shape of the annular seal portion 12a4 formed on the innermost side. For this reason, the design freedom of the shape of the notch 12a1 is greater than the shape of the notch 12a1 being constrained by the shape of the two annular seal portions (12a3, 12a4). It is possible to make the shape of the tool 140 excellent in terms of production, quality, and efficiency.

  In the above-described embodiment, the present invention is implemented by using a plurality of support jigs 140 each including a tapered guide part 141 and a receiving part (step part) 142. It is also possible to implement the present invention using a plurality of pairs of support jigs 140A, 140B shown in FIG. Each support jig 140A includes a tapered guide portion 141a, and does not include a receiving portion (step portion). On the other hand, each support jig 140B includes a receiving portion (step portion) 142a and does not include a tapered guide portion. For this reason, it is possible to reduce the cost by simplifying the shapes of the support jigs 140A and 140B. In particular, as in the present embodiment, the notch 12a1 can be formed on the inner peripheral surface side of the metal ring 11, and by using the support jig 140 provided with the tapered guide portion 141 described above, the cavity The metal ring 11 can be easily positioned in S.

  In the above-described embodiment, the plurality of support jigs 140 are provided with the tapered guide portions 141. However, the plurality of support jigs 140 may be provided without the tapered guide portions 141. Is also possible. In this case, the effect of the tapered guide portion 141 cannot be expected, but the notch 12a1 having the shape shown in FIG. For this reason, the waterproof improvement effect in the boot 10 can be expected. In this case, it is also possible to change the shape of the receiving portion (step portion), and as shown in FIG. 7, the engagement area with the one side end surface in the axial direction of the metal ring 11 is set as shown in FIG. It is also possible to carry out by making it larger than the form.

  Further, in the above-described embodiment, the present invention is applied to the dust boot 10 disposed between the piston 20 of the movable caliper type disk brake device for a vehicle and the cylinder body 30 of the caliper. In the pin slide mechanism of the movable caliper type disc brake device for a vehicle, it can be similarly applied to the pin boot disposed between the caliper and the slide guide pin, and is not limited to the above embodiment. .

It is a fragmentary sectional view showing one embodiment of a ring mold type boot by the present invention. It is an expanded sectional view in the natural state (free state) of the boots shown in FIG. It is a longitudinal cross-sectional view of the shaping | molding die which manufactures the boot shown in FIG. FIG. 4 is an enlarged perspective view of the support jig shown in FIG. 3. It is the perspective view which showed the deformation | transformation embodiment of the support jig shown in FIG. FIG. 4 is a cross-sectional view corresponding to FIG. 2 when the tapered guide portion is removed from the support jig shown in FIG. 3. FIG. 2 is a cross-sectional view corresponding to FIG. 2 when the taper-shaped guide portion is eliminated from the support jig shown in FIG. 3 and the engagement area with the end surface on one side in the axial direction of the metal ring is larger than that in the embodiment of FIG. It is.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Boot, 11 ... Metal ring, 12 ... Elastic body, 12a ... Annular outer periphery, 12a1 ... Notch, 12a2 ... First annular seal part, 12a3 ... Second annular seal part, 12a4 ... Third annular seal part, 12b ... An annular inner peripheral portion, 12c ... bellows portion, 100 ... molding die, 110 ... lower die, 120 ... upper die, 130 ... middle die, S ... cavity, 140 ... support jig, 141 ... guide portion, 142 ... receiving portion

Claims (2)

  In the ring mold type boot (10) in which the metal ring (11) is embedded in the elastic body (12), the elastic body (12) prevents foreign matters such as dust and moisture from entering the inside. At least two annular seal portions (12a3, 12a4), and a notch (12a1) in which the metal ring (11) is partially exposed is formed inside the annular seal portions (12a3, 12a4). Ring mold type boots characterized by   The metal ring (11) is embedded in the cavity (S) formed by the mold (100), and the molten elastic material is injected into the cavity (S). In the manufacturing method of a ring mold type boot for manufacturing a boot (10), when the metal ring (11) is disposed in the cavity (S), the metal ring (11) is moved with respect to the cavity (S). A tapered guide portion (141) that guides coaxially, and an axially one side end surface of the metal ring (11) and a radial inner side when the metal ring (11) is disposed in the cavity (S). The metal ring (11) is positioned on the mold (100) via a plurality of support jigs (140) provided with receiving portions (142) that contact the peripheral surface and receive the metal ring (11). In fit state, method for producing the ring mold boots, characterized in that disposed in the cavity (S).

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