JP2014126193A - Ring mold boot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the position shift from occurring between a rubbery elastic body and a metal ring when fitted to a partner member, by providing a position shift prevention part in the metal ring.SOLUTION: A ring mold boot has a metal ring 7 embedded in an annular rubbery elastic body 2. The metal ring 7 is provided with a position shift prevention part 8 for preventing position shift with the rubbery elastic body 2. The position shift prevention part 8 comprises: a curved concave portion 8a continuously formed in the circumferential direction (annular direction) on an outer circumferential surface 7b of the metal ring 7; and a curved convex part 8b continuously formed in the circumferential direction (annular direction) on an inner circumferential surface 7a facing the concave part 8a to each other.

Description

  The present invention is, for example, a piston boot that is provided between a piston and a cylinder used for a caliper of a disc brake and prevents intrusion of dust and moisture from the outside, and includes a metal inside the rubber-like elastic body. The present invention relates to an improvement of a ring mold type boot formed by embedding a ring (metal annular core material).

  A piston boot is known as an example of a ring mold type boot. This piston boot is provided between a piston used for a caliper of a disc brake and a cylinder, and shields dust and moisture from the outside so as not to enter the cylinder.

The piston boot is made of a rubber-like elastic body, and has a large-diameter annular portion (first annular end portion) and a small-diameter annular shape that is concentric with the large-diameter annular portion (first annular end portion) and has a small diameter. A telescopic bellows portion provided between the portion (second annular end portion), the large-diameter annular portion (first annular end portion), and the small-diameter annular portion (second annular end portion); Are united.
The piston boot is fitted with the large-diameter annular portion (first annular end portion) fitted into the opening of the cylinder, and the small-diameter annular portion (second annular end portion) on the outer periphery of the piston. It is fitted into the formed outer circumferential groove.
In this piston boot, for the purpose of ensuring the fitting of the large-diameter annular portion (first annular end portion) to the opening of the cylinder, the metal ring (metallic annular core member) It is embedded in the large-diameter annular portion (first annular end portion). (See Patent Document 1).

Conventionally, there has been room for improvement in workability when assembling such a piston boot between a piston and a cylinder.
That is, when the large-diameter annular portion (first annular end portion) is fitted into the opening of the cylinder, the metal ring is embedded between the rubber ring and the rubber-like elastic body around the metal ring. There was a risk that a shift would occur.
This is because when the large-diameter annular portion (first annular end portion) of the piston boot is fitted into the opening of the cylinder, the surface that rubs against the inner peripheral surface of the opening is a rubber-like elastic body. This is due to the difficulty.
When such a fitting failure occurs, there is a possibility that the sealing performance may be deteriorated. Therefore, in the conventional piston boot, the piston boot may be assembled carefully.

JP 2002-327849 A

  The present invention has been made in view of such room for improvement of conventional piston boots, and the object of the present invention is to provide a metal ring with a misalignment prevention portion so that it can be fitted to a mating member. An object of the present invention is to provide a ring mold type boot that prevents the occurrence of displacement between the rubber-like elastic body and the metal ring.

The technical means made by the present invention in order to achieve the above-mentioned object is a ring mold type boot in which a metal ring is embedded in a rubber-like elastic body.
The metal ring is a ring mold type boot having a misalignment prevention portion for preventing misalignment with the rubber-like elastic body.

  A second invention is characterized in that, in the first invention, the metal ring is formed in a ring shape by fixing a position between the end portions of the linear body after forming the position shift prevention portion in the linear body. This is a ring mold type boot.

  3rd invention has a welding part formed by joining the butt | matching part of edge parts by welding, after processing a linear body into a ring shape in 1st invention, This welding part is a position shift prevention part. This is a ring mold type boot characterized by the following.

A fourth invention is a ring mold type boot provided between a piston and a cylinder used in a caliper of a disc brake in any one of the first to third inventions.

  According to the present invention, by providing the misalignment prevention portion on the metal ring, it is possible to prevent occurrence of misalignment between the rubber-like elastic body and the metal ring when fitting to the mating member. It is possible to provide a ring mold type boot capable of improving the workability.

It is a schematic sectional drawing which shows an example of the use condition in one Embodiment of the ring mold type boot of this invention. 1 is a schematic cross-sectional view showing an embodiment of a ring mold type boot of the present invention with a part omitted. It is a schematic front view which shows one Embodiment of the ring mold type boot of this invention. It is an example of other embodiments of the metal ring which constitutes the ring mold type boot of the present invention, and (a) shows a schematic cross section showing a part of the metal ring of the second embodiment partially omitted and a part of the peripheral surface. The figure to show, (b) is a figure which abbreviate | omits some metal rings of 3rd embodiment, and shows the outline section and a part of peripheral surface side by side, (c) is a part of metal ring of 4th embodiment FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of the processing method of the metal ring which comprises the ring mold type | mold boot of this invention, (a) is a schematic front view of the linear body which abbreviate | omits one part, (b) is an annular linear body. It is a schematic front view which shows the process processed into (ring shape) (The state which shows the state which edge parts are spaced apart before welding). It is a schematic sectional drawing which abbreviate | omits and shows an example of the other method of joining the edge parts of a linear body. It is a schematic sectional drawing which shows the processing process of the conventional metal ring, (a) is sectional drawing of the metal plate-shaped body before a process, (b) is drawing processing the metal plate-shaped body with a press. (C) is a schematic cross-sectional view in which an unnecessary portion is cut and a metal ring is formed after the press working. It is the schematic of the metal ring formed by the conventional process, Comprising: (a) is a whole schematic sectional drawing, (b) is an expanded sectional view. It is an example of another embodiment of the metal ring which comprises the ring mold type boot of the present invention, (a) is a perspective view of a metal ring, (b) is a typical partial expansion perspective view showing an example of a welding part, (C) is typical sectional drawing which shows an example of a welding part, (d) is typical plan view which shows an example of a welding part, (e) is typical sectional drawing which shows the other example of a welding part. is there. It is a modification of the metal ring which comprises the ring mold type boot of this invention, (a) is a perspective view of a metal ring, (b) is a typical partial expanded perspective view which shows an example of a welding part, (c) is welding. FIG. 4D is a schematic cross-sectional view showing an example of a welded portion, FIG. 4D is a schematic plan view showing an example of a welded portion, and FIG. 5E is a schematic cross-sectional view showing another example of a welded portion.

  Hereinafter, an embodiment of the ring mold type boot of the present invention will be described. In addition, this embodiment is only one embodiment of the present invention, and is not construed as being limited thereto. Any design change can be made within the scope of the present invention.

  FIG. 1 shows an example of a disc brake 15 showing a use state of a piston boot 1 according to an embodiment of the present invention, and an annular step portion formed in an opening 20 of a cylinder 19 of a caliper 16 constituting the disc brake 15. 21 and the piston boot 1 of this embodiment are provided so that it may span between the outer peripheral groove | channel 26 formed in the outer peripheral surface 25 of the piston 24. As shown in FIG. In the figure, reference numeral 17 denotes a piston seal.

In the present embodiment, as shown in FIG. 1, an example of a caliper that presses only one pad (inner pad) 18 with a piston 24 is shown. In the configuration of the disc brake shown in the drawings, the configuration other than the piston boot 1 according to the present invention can be applied with a well-known configuration within the scope of the present invention, and a detailed description thereof will be omitted.
The piston 24 moves in the direction indicated by the arrow Y in the figure by the pressure action of the hydraulic pressure supplied into the cylinder 19 to advance the pad 18. In FIG. 1, reference numeral 6 denotes a disk rotor.

  The piston boot 1 includes a rubber-like elastic body 2 formed of a rubber-like member such as rubber or resin having good elasticity, and a metal ring (metal annular core) 7 embedded in the rubber-like elastic body 2. And is integrally formed in an annular shape as a whole by molding (see FIGS. 2 and 3).

  The rubber-like elastic body 2 includes a large-diameter annular portion (first annular end portion) 3, a small-diameter annular portion (second annular end portion) 4 that is concentric with the large-diameter annular portion 3 and has a small diameter, A telescopic bellows portion 5 provided between the diameter annular portion 3 and the small diameter annular portion 4 is integrally formed (see FIGS. 2 and 3).

The large-diameter annular portion 3 has a substantially rectangular shape in cross section and is formed with a predetermined thickness in the radial direction. In the present embodiment, the outer peripheral surface 3a has a curved convex shape for alignment. A strip 30 is formed. This ridge 30 is fitted into a curved ridge 22 formed in the annular step 21 of the cylinder 19. In the present embodiment, the end surface of the large-diameter annular portion 3 is provided with a dust seal 3 b that presses against the wall surface 23 of the annular step portion 21 of the cylinder 19.
In addition, the protruding item | line part 30 and the dust seal | sticker 3b with which this embodiment is provided are not an essential component of this invention, and even if it is a form which does not have these, it is in the scope of this invention.
A plurality of the ridges 30 may be provided together with the ridges 22 or may be provided intermittently. A plurality of dust seals 3b may be provided.
The shape of the protruding portion 30 (and the recessed portion 22) and the dust seal 3b is not limited, and the design can be changed within the scope of the present invention.

  The small-diameter annular portion (second annular end portion) 4 is formed in a rectangular shape in a sectional view that is shorter in the axial direction than the large-diameter annular portion 3, and is fitted in an outer circumferential groove 26 formed in the outer circumferential surface 25 of the piston 24. It is fitted with.

The bellows portion 5 is not particularly limited as long as it does not restrict the movement of the piston 24 in the Y-axis direction, and a well-known general configuration is applied within the scope of the present invention.
The shapes of the large-diameter annular portion 3, the small-diameter annular portion 4, and the bellows portion 5 are not particularly limited, and the design of the piston boot 1 can be changed within the scope of the present invention.

  The metal ring 7 is embedded in the large-diameter annular portion (first annular end portion) 3 at the time of molding so that the large-diameter annular portion 3 fits securely into the opening 20 of the cylinder 19. (See FIG. 2).

  In the present embodiment, the metal ring 7 is formed by rolling a metal linear body (wire) 13 into a rectangular shape in cross-sectional view, forming a position shift prevention portion described later, and then cutting to a predetermined length L1 ( 5 (a), after processing the cut linear body 13 into a ring shape (FIG. 5 (b)), opposite end portions 13a and 13a are fixedly formed by spot welding or the like, for example. . In FIG. 5, a later-described misregistration prevention unit is not shown.

The reason why the metal ring 7 of the present embodiment is formed by rolling the metal linear body (wire) 13 as described above is as follows.
In the conventional metal ring, first, a metal plate B (the state shown in FIG. 7A) is drawn with a press (the state shown in FIG. 7B), and then unnecessary portions R1 and R2 are cut (for example, It was manufactured by cutting along the lines S1-S1 and S2-S2 in FIG. 7B (states in FIGS. 7A and 7C).
However, when the unnecessary portions R1 and R2 are cut, burrs S are easily generated at the cut portions (particularly corner portions) as shown in FIG. There was a problem like this. For example, when molding a piston boot with an embedded metal ring, the metal ring is set at a predetermined position in a mold cavity (not shown), and then the cavity is filled with a molten material such as rubber or resin and cured. To do. At this time, if there are burrs S ... at the corners of the cut portion, the metal ring may not be set at a predetermined position, and a positional shift may occur. There was a risk of being buried in a displaced state. Further, the burr S may cause damage such as cracks in the surrounding rubber-like elastic body.
For this reason, conventionally, after manufacturing the metal ring, it is necessary to check whether or not the burrs S are generated at the cut portions of the metal ring. Since this was necessary, the manufacturing cost was increased.

  The metal ring 7 is provided with a misalignment prevention portion 8 that prevents misalignment with the rubber-like elastic body 2 (see FIG. 2).

The misalignment prevention unit 8 is provided on the outer peripheral surface 7b of the metal ring 7 so as to surround the curved concave portion 8a continuously formed in the circumferential direction (annular direction) and the inner peripheral surface 7a opposite to the concave portion 8a. It is comprised with the curved-shaped convex part 8b formed continuously over the direction (annular direction) (refer FIG. 2).
According to the present embodiment, when the rubber-like elastic body 2 and the rubber-like elastic body 2 are integrally formed by molding, the rubber-like elastic body 2 enters the concave portion 8a of the metal ring 7 and the convex-like portion 8b bites into the rubber-like elastic body 2. Since the metal ring 7 and the rubber-like elastic body 2 are integrated, the displacement of the large-diameter annular portion 3 when the large-diameter annular portion 3 is fitted to the annular step portion 21 of the opening 20 of the cylinder 19 is prevented. (See FIG. 2).

  This misalignment prevention portion 8 is formed by pressing or other known processing methods before processing the metal ring 7 into a ring shape. For example, the misalignment prevention unit 8 is formed by machining in an elongated state before being cut into a linear body 13 having a predetermined length. Then, after cutting into a linear body 13 having a predetermined length, the linear body 13 is processed into a ring shape, and the end portions 13a and 13a are fixed to complete the metal ring 7 of the present embodiment.

As shown in FIG. 2, the misregistration preventing portion 8 is formed in a curved concave portion 8a and a convex portion 8b. However, the concave portion 8a and the convex portion 8b are not limited to a curved shape, and are conical and rectangular. It may be a concave portion and a convex portion formed in a shape or the like, and the design can be arbitrarily changed.
Further, the concave portion 8a and the convex portion 8b do not need to be continuously provided in the circumferential direction (annular direction) of the metal ring 7, and a plurality of intermittent portions are provided at predetermined intervals in the circumferential direction (annular direction). Also good.
The misalignment prevention unit 8 is not limited to the form shown in FIG. 2 and can be appropriately changed in design within the scope of the present invention. Here, an example of another embodiment of the misalignment prevention unit 8 will be described with reference to FIG. 4A shows the second embodiment, FIG. 4B shows the third embodiment, and FIG. 4C shows the fourth embodiment.

FIG. 4A shows an example in which a plurality of holes 8c formed so as to penetrate the outer peripheral surface and the inner peripheral surface of the metal ring are formed at predetermined intervals in the circumferential direction (annular direction). It is.
According to the present embodiment, if the rubber-like elastic body 2 and the rubber-like elastic body 2 are integrally formed by molding, the rubber-like elastic body 2 is integrally formed with the plurality of holes 8c of the metal ring 7, so that the metal ring 7 and the rubber-like elastic body 2 are firmly integrated, and it is possible to prevent displacement. That is, the hole 8 c functions as the misalignment prevention unit 8.
In the present embodiment, each hole 8c is formed in the same rectangular shape, but the shape of the hole 8c is not limited to this, and the design can be arbitrarily changed. Further, the shape of the hole 8c may be the same or different in size between the opening on the outer peripheral surface 7b side and the opening on the inner peripheral surface 7a side. Further, the arrangement interval is also arbitrary, and may be a constant interval or a different interval. Further, the size of each hole 8c may be different.
Further, in this embodiment, a configuration in which holes are provided on the same line in the circumferential direction (annular direction) is adopted, but it may be provided in a staggered manner or may be provided randomly. The design can be changed within the scope of the present invention.

FIG. 4B shows an embodiment in which the metal ring 7 is formed such that the left and right regions 8d and 8e are bent slightly in the direction of the inner peripheral surface 7a from the substantially central position, that is, in a substantially C shape in a sectional view. It is an example.
According to the present embodiment, when the rubber-like elastic body 2 and the rubber-like elastic body 2 are integrally formed by molding, the left and right regions 8d and 8e of the metal ring 7 are in a state of biting into the rubber-like elastic body 2. As a result, the integration of the metal ring 7 and the rubber-like elastic body 2 is strengthened, and the displacement can be prevented. That is, the left and right bent regions 8d and 8e function as the position shift prevention unit 8.
In addition, it is also within the scope of the present invention that the metal ring 7 has a shape in which the left and right regions 8d and 8e are slightly bent in the direction of the outer peripheral surface 7b from the substantially central position, that is, substantially upward in a sectional view. is there. The degree of bending of the left and right regions 8d and 8e is not particularly limited, and can be changed as appropriate, for example, by bending into a substantially V shape in a sectional view.

FIG. 4C is an example of an embodiment in which the outer peripheral surface 7 b of the metal ring 7 is subjected to rough surface processing (knurling) in which a plurality of grooves 8 f intersect.
According to the present embodiment, when the rubber-like elastic body 2 and the rubber-like elastic body 2 are integrally formed by molding, the rubber-like elastic body 2 is bitten into the rough surface process formed on the outer peripheral surface 7b of the metal ring 7. Therefore, the integration of the metal ring 7 and the rubber-like elastic body 2 becomes strong, and it is possible to prevent misalignment.
It is also possible to apply the same rough surface processing to the inner peripheral surface 7a of the metal ring 7.
Further, the rough surface processing is not limited to the one formed by intersecting the plurality of grooves 8f as in the illustrated example, and may be a rough surface provided with a number of fine protrusions.

Furthermore, although not shown in the figure, a continuous groove formed continuously in the circumferential direction on the outer peripheral surface 7b of the metal ring 7 and a continuous circumferential surface on the inner peripheral surface 7a opposed to the concave groove. What is comprised with the protruding item | line part formed also functions as the position shift prevention part 8 which comprises this invention. Of course, a mode in which a concave strip portion is provided on the inner peripheral surface 7a and a convex strip portion is provided on the outer peripheral surface 7b is also included.
Further, it is within the scope of the present invention even if it is constituted by all or any combination of the respective forms of the misregistration prevention units 8 (8a-8f) shown in FIGS.

In the present embodiment, the linear body 13 constituting the metal ring 7 is a metal linear body (flat wire) in which both side surfaces 7c, 7c in the case of the metal ring 7 are rectangular in cross section, but both side surfaces It is preferable that 7c and 7c have an elliptical cross-sectional shape having an arc shape because no edges (corner portions) are generated.
In order to make the both side surfaces 7c, 7c have an elliptical shape in a sectional view, a circular linear body in a sectional view may be rolled.
The shape of the metal ring 7 is not particularly limited in terms of cross-sectional view, and the design can be changed within the scope of the present invention.
The metal ring 7 has side surfaces 7c and 7c formed flat, and all or any of the four corner portions connecting the side surface 7c and the inner peripheral surface 7a and the side surface 7c and the outer peripheral surface 7b. May be formed in a circular arc shape, and such a shape is also within the scope of the present invention.

  Furthermore, although the radial thickness of the metal ring 7 is also arbitrary, if it is too thin, the side surface 7c of the metal ring 7 will approach the shape of the cutting edge, so care must be taken in setting the thickness.

Moreover, in this Embodiment, what used spot welding was illustrated for fixation of edge part 13a, 13a, However, The means of fixation is not specifically limited to spot welding, In the scope of the present invention. The design can be changed.
For example, as shown in FIG. 6, each end 13a, 13a may be formed to have a fitting structure. That is, for example, in FIG. 6, a convex portion 13b is provided at one end portion (right end portion in the drawing) 13a, and the convex portion is provided at the other end portion (left end portion in the drawing). The recessed part 13c which 13b fits may be provided, and the edge parts 13a and 13a may be fixed by fitting by this convex part 13b and the recessed part 13c. The fitting shown in FIG. 6 is merely an example, and the design can be changed within the scope of the present invention.

Next, still another embodiment of the metal ring used for the ring mold type boot of the present invention will be described with reference to FIG.
In the embodiment described above, the misalignment prevention portion 8 is formed so as to penetrate the concave portion 8a and the convex portion 8b formed in the metal ring 7 and the outer peripheral surface and inner peripheral surface of the metal ring 7. Although the hole portion 8c and the like are illustrated, in the present embodiment, as shown in FIGS. 9A to 9E, the misalignment prevention portion 8 is the end of the linear body 13 constituting the metal ring 7. It is comprised by the welding part 100a which joins the butt | matching part of the parts 13a and 13a.

  In the metal ring 7, after the linear body 13 is processed into a ring shape, the butted portions of the end portions 13a and 13a are joined at two places by spot welding or the like, for example. The two welded portions 100 a are recessed from the outer peripheral surface of the metal ring 7, and the recessed portions serve as the misalignment preventing portion 8. Note that the welded portion 100 a is not limited to two locations, and may be one or three locations in the width direction of the linear body 13. Moreover, as shown in FIG.9 (e), the welding part 100a may penetrate the linear body 13, and may form a bulging part in the internal peripheral surface of the linear body 13, In this case, an inner peripheral surface side is sufficient. The bulge portion also functions as the misalignment prevention portion 8.

Next, the modification of the metal ring used for the ring mold type boot of this invention is demonstrated based on FIG.
Even in this embodiment, as shown in FIGS. 10A to 10E, the misalignment prevention unit 8 joins the butted portions of the end portions 13 a and 13 a of the linear body 13 constituting the metal ring 7. It consists of a welded part 100b.

  In the metal ring 7, after the linear body 13 is processed into a ring shape, the butted portions of the end portions 13a and 13a are joined at two places by spot welding or the like, for example. The two welded portions 100 b swell more than the outer peripheral surface of the metal ring 7, and the swelled portions serve as the misalignment preventing portions 8. Note that the welded portion 100b is not limited to two places, and may be one place or three places in the width direction of the linear body 13. As shown in FIG. 10 (e), the welded portion 100b may penetrate the linear body 13, and a bulging portion may also be formed on the inner peripheral surface of the linear body 13. In this case, the inner peripheral surface side The bulge part of the swell also functions as the misalignment prevention part 8.

  According to these embodiments, the dent and bulge of the welded portion 100a (100b) function as the misregistration preventing portion 8, so that it is not necessary to form the misalignment preventing portion 8 by machining in the linear body 13. Cost reduction can be achieved.

In the above embodiment, the piston boot is illustrated as an example of the ring molding type boot. However, it is needless to say that the present invention can be diverted to other boots.

DESCRIPTION OF SYMBOLS 1 Ring mold type boot 2 Rubber-like elastic body 7 Metal ring 8 Position shift prevention part 13 Linear body 13a End part 15 Disc brake 16 Caliper 18 Pad 19 Cylinder 24 Piston

Claims (4)

In the ring mold type boot in which the metal ring is embedded in the rubber-like elastic body,
A ring mold type boot, wherein the metal ring is provided with a misalignment prevention portion for preventing misalignment with the rubber-like elastic body.   2. The ring mold according to claim 1, wherein the metal ring is formed in a ring shape by forming the misalignment prevention portion on the linear body and then fixing between ends of the linear body. boots.   The metal ring has a welded portion obtained by processing a linear body into a ring shape and then joining the butted portions of the end portions by welding, and the welded portion serves as the misalignment preventing portion. The ring mold type boot according to claim 1.   The ring mold type boot according to any one of claims 1 to 3, wherein the ring mold type boot is provided between a piston and a cylinder used for a caliper of a disc brake.

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