JP2007239970A - Dust cover for ball joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dust cover for ball joint which can prevent a periphery edge of brim portion of ball stud from contacting a dust cover body. <P>SOLUTION: A dust cover 10 for the ball joint comprises a dust cover body 11 formed with a flexible material, and a reinforcing body 12 laid underground within the dust cover body 11. And, the dust cover body 11 includes a first attaching portion 21 to be attached at small opening side, a second attaching portion 22 to be attached at big opening side, and a deformed portion 23 located between the first attaching portion 21 to be attached and the second attaching portion 22 to be attached. Furthermore, the reinforcing body 12 includes an annular main portion 31, and a projection portion 32 for gap holding which holds a gap 13 between a periphery portion 5 and the dust cover body 11 when the projection portion rotates with respect to a housing 8 of the ball stud 2 by being arranged to be hit with this annular main body 31. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a dust cover for a ball joint used for a ball joint.

Conventionally, a dust cover for a ball joint (see, for example, Patent Document 1) in which annular reinforcing bodies are respectively embedded in upper and lower ends of a cylindrical dust cover body formed of a flexible material, as shown in FIG. There is known a ball joint dust cover in which an annular reinforcing body B is embedded in an upper end portion of a cylindrical dust cover main body A formed of a flexible material.
Japanese Utility Model Publication 2-36973

  However, in the conventional dust cover for a ball joint, as is apparent from FIG. 11, for example, when the ball stud C is rotated with respect to the housing D, the outer peripheral edge of the flange portion of the ball stud C is the dust cover main body A. There is a risk of touching.

  This invention is made | formed in view of such a point, and it aims at providing the dust cover for ball joints which can prevent the malfunction which the outer periphery of the collar part of a ball stud contacts a dust cover main body.

  The dust cover for a ball joint according to claim 1, comprising a cylindrical dust cover body formed of a flexible material, and an annular reinforcing body embedded in the dust cover body, wherein the dust cover body Is attached to a stud part of the ball stud and a flange projecting on the outer peripheral side of the stud part, and a housing for rotatably holding the ball part of the ball stud. And a deformable portion positioned between the first mounted portion and the second mounted portion, and the reinforcing body is embedded in the first mounted portion. An annular main body portion, and a protrusion for projecting the annular main body portion, and a clearance holding protrusion that holds a clearance between the outer peripheral edge of the flange portion and the dust cover main body when the ball stud rotates relative to the housing. Have Than is.

  The dust cover for a ball joint according to claim 2 is the dust cover for the ball joint according to claim 1, wherein the protrusion for holding the gap is configured by an annular plate portion protruding from the outer peripheral edge of the annular main body portion. It is what.

  According to the invention according to claim 1, since the reinforcing body has the gap holding protrusion for holding the gap between the outer peripheral edge of the flange portion of the ball stud and the dust cover body when the ball stud rotates with respect to the housing, The trouble that the outer peripheral edge of the flange portion of the ball stud contacts the dust cover main body can be prevented.

  According to the invention which concerns on Claim 2, the outer peripheral edge of the flange part of a ball stud is made into a dust cover by comprising the protrusion part for clearance holding | maintenance of a reinforcement body by the annular plate part protrudingly provided by the outer peripheral edge of the annular main-body part. Problems that come into contact with the main body can be effectively prevented.

  An embodiment of a dust cover for a ball joint of the present invention will be described with reference to the drawings.

  In FIG. 1 and FIG. 2, 1 is a ball joint, and this ball joint 1 is used for a suspension device of a motor vehicle, a steering device, or the like.

  The ball joint 1 includes a ball stud 2 made of steel or the like, and the ball stud 2 includes a substantially spherical ball portion 3, a shaft-like stud portion 4 projecting integrally with the ball portion 3, and the stud portion 4. It has an annular flange 5 that is integrally projected on the outer peripheral side.

  The ball joint 1 also includes a housing 8 such as a substantially cylindrical socket that rotatably holds the ball portion 3 of the ball stud 2 via bearing seats 6 and 7 made of synthetic resin or the like.

  Between the flange 5 of the ball stud 2 and the cover step 9 of the housing 8, a substantially cylindrical shape is provided so as to cover a portion of the stud 4 located between the ball 3 and the flange 5. A dust cover 10 for the ball joint is provided.

  Here, the dust cover 10 for the ball joint is composed of a dust cover main body 11 having a substantially cylindrical shape with openings at both ends formed of a flexible material such as rubber, and a dust cover main body formed of resin or metal. A substantially annular reinforcing body (insert ring) 12 that is embedded in 11 and reinforces the dust cover main body 11 is provided.

  In addition, the ball joint dust cover 10 sets the reinforcing body 12 in a mold that is a mold of a predetermined shape, and then pushes a flexible material such as liquid rubber into the mold to solidify it. This is an insert-molded product produced by integrally providing the dust cover main body 11 on the reinforcing body 12.

  As shown in FIGS. 1 and 2, the dust cover main body 11 has a surface on the side facing the outer peripheral surface of the stud portion 4 of the ball stud 2 and the ball portion 3 of the flange portion 5 of the ball stud 2 (in FIG. 1). , Lower surface) and a second attached portion 22 attached to the cover step 9 of the housing 8 having a first attached portion 21 on one end side (small opening side) in the axial direction. On the other end side (large opening side) in the axial direction, and a bellows-shaped deformed portion 23 located between the first attached portion 21 and the second attached portion 22 in the intermediate portion in the axial direction. .

  The first attached portion 21 has a concave reinforcing body accommodating chamber 25 that opens toward the flange portion 5, and the reinforcing body 12 is accommodated in the reinforcing body accommodating chamber 25. The first attached portion 21 has an annular lip portion 26 that faces the reinforcing body accommodation chamber 25 and contacts the lower surface of the flange portion 5 so as to have a sealing property. A plurality of annular lip portions 27 are formed on the inner peripheral surface side of the first mounted portion 21 so as to be in contact with the outer peripheral surface of the stud portion 4 so as to have a sealing property. The lip portion 27 is slidable in the axial direction of the stud portion 4 with respect to the outer peripheral surface of the stud portion 4.

  The second attached portion 22 is fitted into the cover step 9 of the housing 8 and is fitted and fixed to the cover step 9 by an annular fixing member 28.

  The deformable portion 23 is configured by a sheet-like portion having a substantially constant thickness dimension, and includes a plurality of, for example, three first curved surface portions 29a, second curved surface portions 29b, and third curved surface portions 29c, and a first cover. A first flat surface portion 30a located between the attachment portion 21 and the first curved surface portion 29a, a second flat surface portion 30b located between the first curved surface portion 29a and the second curved surface portion 29b, and a second curved surface portion It has the 3rd plane part 30c located between 29b and the 3rd curved surface part 29c, and the 4th plane part 30d located between the 3rd curved surface part 29c and the 2nd to-be-attached part 22. FIG.

  On the other hand, the reinforcing body 12 has a shape matching the film shape of the dust cover main body 11, and as shown in FIGS. 1 to 4, a circle embedded in the first attached portion 21 of the dust cover main body 11. An annular main body 31 and an outer peripheral edge of the annular main body 31 are integrally protruded outward and embedded in the first attached portion 21 of the dust cover main body 11 so that the ball stud 2 can be rotated with respect to the housing 8. It has a gap holding projection 32 for holding a gap 13 between the corner 5a of the outer peripheral edge of the flange 5 and the dust cover main body 11 when moving.

  The annular main body 31 includes a main body portion 35 having a substantially square cross section, a flange contact portion 36 that protrudes from the main body portion 35 and contacts the flange portion 5, and a protrusion portion 37 that protrudes inward from the main body portion 35. Configured.

  The gap holding projection 32 is formed of an annular annular plate 38 that projects integrally with the outer peripheral edge of the annular body 31 and projects outward from the body 35 of the annular body 31. . The annular plate portion 38 is inclined with respect to a reference plane orthogonal to the central axis α of the ball stud 2 so that the distance from the flange portion 5 gradually increases from the inner peripheral edge toward the outer peripheral edge. The outer peripheral edge of the annular plate portion 38 is located at a position facing the corner portion 5 a of the outer peripheral edge of the flange portion 5 of the ball stud 2. The thickness dimension of the annular plate portion 38 gradually decreases from the inner peripheral edge toward the outer peripheral edge. Further, the annular plate portion 38 is always positioned on the same plane as the first flat portion 30a of the deformable portion 23 of the dust cover main body 11.

  Next, the operation and the like of the ball joint 1 will be described.

  From the state shown in FIG. 1, that is, the state where the central axis α of the ball stud 2 and the central axis β of the housing 8 are located on the same straight line, the ball stud 2 is rotated with respect to the housing 8 as shown in FIG. That is, when rocking and sliding, one side of the deformed portion 23 of the dust cover body 11 is contracted and deformed, and the adjacent flat portions 30a, 30b, 30c, 30d on the one side are brought close to each other, and the dust cover body The other side of the eleven deformation portions 23 is stretched and deformed, and the adjacent flat portions 30a, 30b, 30c, 30d on the other side are separated from each other.

  At this time, since the gap 13 between the corner 5a of the outer peripheral edge of the flange 5 of the ball stud 2 and the first attached portion 21 of the dust cover main body 11 is kept constant, the flange 5 of the ball stud 2 is maintained. The corner portion 5a does not come into contact with the first flat portion 30a of the deformation portion 23 of the dust cover main body 11.

  As described above, according to the ball joint 1, the circular annular plate 38 constituting the gap holding projection 32 is provided on the outer peripheral edge of the annular main body 31 of the reinforcing body 12. When turning or setting the dust cover 10 for the ball joint, it is possible to prevent the corner 5a of the outer peripheral edge of the flange 5 of the ball stud 2 from contacting the flexible dust cover body 11, and Changes in the shape of the dust cover main body 11 due to deterioration, damage to the dust cover main body 11 due to icing, flying stones, and the like can be suppressed.

  For example, in order to improve the moldability of the dust cover 10 for ball joints, a plurality of holes 41 for flowing a flexible material such as liquid rubber at the time of insert molding as shown in FIGS. 8 or 9, the annular plate 38 may be provided with a plurality of notches 42 for flowing a flexible material such as liquid rubber during insert molding.

  When the hole 41 and the notch 42 are provided in the annular plate portion 38 of the reinforcing body 12, as shown in FIG. 7, the outer mold 51 and the inner mold are inserted from the rubber injection port during the insert molding of the ball joint dust cover 10. Liquid rubber (flexible material) that has entered between 52 flows into the lip forming recess 53 for forming the lip portion 26 of the dust cover body 11 through the hole 41 and the notch 42. For this reason, compared with the structure which does not provide the hole part 41 and the notch part 42, rubber filling time can be shortened and a moldability can be improved.

  The ball joint dust cover 10 is not limited to one formed by insert molding.For example, after the dust cover main body 11 and the reinforcing body 12 are made separately, the dust cover main body 11 is provided in the reinforcing body accommodating chamber 25. What formed by inserting the reinforcing body 12 may be used.

  Further, the gap holding protrusion 32 is not limited to the one configured by the annular plate portion 38, but is configured by a plurality of plate-like portions protruding from the outer peripheral portion of the annular main body portion 31. Alternatively, it may be configured by a plurality of rod-like portions protruding from the outer peripheral portion of the annular main body 31 and extending in the radial direction of the annular main body 31.

It is sectional drawing of the ball joint provided with the dust cover for ball joints concerning one embodiment of the present invention. It is sectional drawing at the time of the state which the ball joint same as the above rotated. It is a top view of the reinforcement body of the dust cover for ball joints same as the above. It is sectional drawing of a reinforcement body same as the above. It is a top view of the reinforcement body of the dust cover for ball joints concerning other embodiments of the present invention. It is sectional drawing of a reinforcement body same as the above. It is sectional drawing which shows the flow of the rubber at the time of shaping | molding of the dust cover for ball joints same as the above. It is a top view of the reinforcement body of the dust cover for ball joints concerning other embodiment of this invention. It is sectional drawing of a reinforcement body same as the above. It is sectional drawing of the ball joint provided with the dust cover for conventional ball joints. It is sectional drawing at the time of the state which the ball joint same as the above rotated.

Explanation of symbols

2 Ball Stud 3 Ball Part 4 Stud Part 5 Gutter 8 Housing
10 Dust cover for ball joint
11 Dust cover body
12 Reinforcing body
13 Clearance
21 First mounted part
22 Second mounted part
23 Deformation part
31 Annular body
32 Gap retaining projection
38 Annular plate

Claims (2)

A cylindrical dust cover body formed of a flexible material;
An annular reinforcing body embedded in the dust cover body,
The dust cover body is
A first attached portion that is attached to the stud portion of the ball stud and the flange portion protruding from the outer peripheral side of the stud portion;
A second attached portion that is attached to a housing that rotatably holds the ball portion of the ball stud;
A deformation portion located between the first attached portion and the second attached portion;
The reinforcing body is
An annular main body embedded in the first mounted portion;
Protruding from the annular main body, and having a gap holding projection for holding a gap between the outer peripheral edge of the flange and the dust cover main body when the ball stud rotates with respect to the housing. Dust cover for ball joint. The ball joint dust cover according to claim 1, wherein the gap holding protrusion is configured by an annular plate protruding from an outer peripheral edge of the annular main body.

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