JP7267593B2 - Ball joint and its dust cover - Google Patents

Description

TECHNICAL FIELD The present invention relates to a dust cover for a ball joint mounted across a cover mounting portion of a receiving side member and a stud portion of a ball side member, and a ball joint including the dust cover.

For example, a ball joint used in a steering system or a suspension system of a vehicle such as an automobile is equipped with a dust cover in order to prevent the intrusion of mud and dust. The dust cover is cylindrical and has lip portions at both ends. The lip portion on one end is fixed to the stud portion of the ball stud, which is the ball-side member, and the lip portion on the other end side is fixed to the groove-shaped cover mounting portion formed around the socket, which is the receiving-side member. be.

Conventionally, there is a socket in which the inner wall surface of the cover mounting portion of the socket is tapered with respect to the stud shaft (see Patent Documents 1 and 2). In recent years, there has been a trend to cut less when molding sockets, and the cover mounting portion is sometimes made by forging. be.

Japanese Utility Model Laid-Open No. 5-22835 Japanese Utility Model Laid-Open No. 3-99217

When the inner wall surface of the cover mounting portion is tapered, the tightening force with which the lip portion of the dust cover is tightened against the cover mounting portion in the direction perpendicular to the axis differs between the position where the diameter is large and the position where the diameter is small. For example, when the outer peripheral side of the lip portion is fastened to the cover mounting portion with a circlip or the like, the tightening force is different at both ends of the circlip. As a result, a force acts on the lip portion to displace the lip portion toward the flange portion that forms the edge of the cover attachment portion, and a high stress is applied from the flange portion to the lip portion. Therefore, when the ball stud is repeatedly oscillated, it is desired that the lip portion of the dust cover does not suffer from material fatigue or damage due to the flange portion due to the above-mentioned stress.

On the other hand, it is conceivable to increase the thickness of the lip portion of the dust cover for reinforcement, but in that case, it is necessary to prevent problems such as the dust cover from becoming difficult to deform.

Therefore, it is desired to improve the durability of the dust cover for the ball joint without increasing the thickness. Such a problem arises not only in ball joints for vehicles but also in ball joints used in arbitrary places.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dust cover for a ball joint that can improve durability without increasing the thickness, and a ball joint having the dust cover.

The ball joint dust cover according to claim 1 is provided with a groove-shaped cover mounting portion recessed in the axial direction on the outer side, and at least a part of the inner wall surface of the cover mounting portion is provided from one axial end side to the other. A cylindrical receiving-side member having an inclined portion expanding toward an end, a ball portion rotatably held by the receiving-side member, and a stud portion projecting from the ball portion and extending to the outside of the receiving-side member. A dust cover of a ball joint attached over the cover mounting portion of the receiving side member and the stud portion of the ball side member for a ball joint including a ball side member comprising a cylindrical main body and a lip portion provided at an axial end of the body portion and at least a portion of which is attached to the cover attachment portion, the lip portion being one end of the cover attachment portion of the receiving side member. a notch formed along a side edge, an inclined facing portion inclined in a shape equal to or substantially equal to the inclined portion and in close contact with the inclined portion, and an absorbing portion recessed in the inclined facing portion. The notch portion is a stepped portion formed by notching in a quadrangular shape at the inner peripheral edge of the lip portion .

The ball joint according to claim 2 is provided with a groove-shaped cover mounting portion recessed in the axial direction on the outer side, and the inner wall surface of the cover mounting portion is at least partly covered from one axial end side to the other axial end side. a cylindrical receiving-side member having an inclined portion that widens toward the receiving-side member; a ball portion that is rotatably held by the receiving-side member; and a stud portion that projects from the ball portion and extends to the outside of the receiving-side member. The dust cover according to claim 1 , which is attached across the cover attachment portion of the receiving side member and the stud portion of the ball side member.

According to the dust cover for a ball joint according to claim 1, by forming a notch portion which is a stepped portion formed by notching in a square shape at the inner peripheral edge of the lip portion, the inclined portion of the inner wall surface of the cover mounting portion and the The stress generated in the lip portion due to contact with the edge portion on the one end side of the cover mounting portion can be dispersed by the displacement of the lip portion from the other end side to the one end side in the axial direction due to contact with the cover. In addition, by forming the absorbing portion in the inclined portion of the lip portion facing the inclined portion, the slippage of the lip portion from the other end side to the one end side in the axial direction due to contact with the inclined portion of the inner wall surface of the cover mounting portion is suppressed, thereby preventing the cover from moving. The stress generated in the lip portion due to contact with the edge portion on the one end side of the mounting portion can be further suppressed. Therefore, it is possible to suppress material fatigue due to repeated operations of the ball-side member, and to improve durability without increasing the thickness.

According to the ball joint of claim 2 , by providing the dust cover of claim 1 , a ball joint having excellent durability can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which expands and shows a part of dust cover of one embodiment of this invention, and a ball joint provided with the same.

A configuration of an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 11 indicates a ball joint. This ball joint 11 is used, for example, in a steering system or a suspension system of a vehicle such as an automobile. That is, the ball joint 11 of this embodiment is for automobiles or vehicles. The ball joint 11 includes a socket 16 as a receiving side member (housing), a ball stud 17 as a ball side member, and a part of the ball stud 17 that is slidably (rotatably) held so that the socket 16 is held. A bearing seat (ball seat) 18, which is a sliding member housed in the socket 16, and a dust cover 19, which is a cover member arranged from the socket 16 to the ball stud 17, are provided. In the following description, the upper side of FIG. 1 is defined as the upper side, and the lower side is defined as the lower side, which is the other end side. Instead, it is assumed that the directions of the one end side and the other end side change according to the arrangement angle of the ball joint 11 . Further, the longitudinal direction of the ball stud 17 in the upright state (neutral state) (that is, the vertical direction in FIG. 1) is called the axial direction (stud axial direction), and the direction perpendicular to the axial direction is called the axial direction. shall be Therefore, it is assumed that the central axis of the ball joint 11 coincides (including substantially coincident) with the central axis of the ball stud 17 in the upright state (neutral state).

The socket 16 is made of metal, for example, and formed in a cylindrical shape with a bottom. That is, the socket 16 has an opening 21 at an upper portion, which is one end, and a lower portion, which is the other end, is closed. Further, the socket 16 has an inner chamber 22, which is a housing portion for housing the bearing seat 18, defined therein. The inner chamber 22 communicates with the opening 21 . A peripheral edge of the opening 21 forms a protruding portion 23 that protrudes toward the center axis of the socket 16 . The protrusion 23 holds the bearing seat 18 in the inner chamber 22 to prevent it from coming off. Further, the socket 16 is formed with a cover attachment portion 25 to which the dust cover 19 is attached. The socket 16 may be integrally formed into a cylindrical shape with a bottom by forging or casting, or may be divided into a plurality of members and assembled together to form a cylindrical shape with a bottom.

The cover attachment portion 25 is recessed in the outer portion of the socket 16 and has a groove shape. The cover attachment portion 25 is positioned around the opening portion 21 . The cover mounting portion 25 is formed continuously over the entire circumference of the socket 16 . That is, the cover mounting portion 25 is formed in an annular shape when viewed in the axial direction. Also, the cover attachment portion 25 is arranged near the upper portion of the socket 16 . The cover attachment portion 25 is positioned downwardly away from the upper end portion of the socket 16 . Therefore, a collar portion 27 forming an edge portion of the cover attachment portion 25 is formed on the outer portion of the upper end portion of the socket 16 . In other words, the flange portion 27 is the remaining portion of the upper end portion of the outer portion of the socket 16 excluding the cover attachment portion 25 . The collar portion 27 is positioned so as to surround the outer periphery of the opening portion 21 . The collar portion 27 extends along the axial direction. A cover attachment portion 25 is positioned adjacent to the lower portion of the flange portion 27 . Also, the collar portion 27 forms the upper end portion of the socket 16 .

The cover attachment portion 25 is formed by connecting a non-inclined portion 32 and an inclined portion 33 between one end surface portion 30 and the other end surface portion 31 . The non-inclined portion 32 and the inclined portion 33 form an inner wall surface (groove wall surface) of the cover attachment portion 25 . One end surface portion 30 forms an end surface portion of the collar portion 27 . One end surface portion 30 forms an upper end portion, which is one end portion of the cover attachment portion 25 . The one end surface portion 30 is a surface extending along the direction perpendicular to the axis. One end face portion 30 is formed in a planar shape. The other end surface portion 31 forms the lower end portion, which is the other end portion of the cover attachment portion 25 . The other end surface portion 31 is a surface extending along the direction perpendicular to the axis. The other end face portion 31 is formed flat. The other end surface portion 31 extends outward in the axial direction with respect to the one end surface portion 30 . The one end surface portion 30 and the other end surface portion 31 are located apart in the axial direction and face each other.

The non-inclined portion 32 is formed continuously with the one end face portion 30 . The non-inclined portion 32 is a surface extending along the axial direction. That is, the non-inclined portion 32 extends in a direction that intersects or is perpendicular to the one end face portion 30 . The non-inclined portion 32 connects the inclined portion 33 and the one end face portion 30 . The non-inclined portion 32 is continuous with the base end portion of the collar portion 27 . The non-inclined portion 32 is formed in the shape of a cylindrical outer surface having a constant or substantially constant diameter. The non-inclined portion 32 is not an essential component.

The inclined portion 33 is formed continuously with the other end face portion 31 . In this embodiment, the inclined portion 33 is positioned apart from the collar portion 27 . The inclined portion 33 is a surface that extends obliquely with respect to the axial direction. In addition, the inclined portion 33 is a surface extending inclined with respect to the direction perpendicular to the axis. That is, the inclined portion 33 extends in a direction intersecting with the other end face portion 31. As shown in FIG. The non-inclined portion 32 and the other end face portion 31 are connected by the inclined portion 33 . The inclined portion 33 is formed in the shape of a truncated cone outer surface. The inclined portion 33 is gradually enlarged (diameter-enlarged) from the one axial end side, that is, the non-inclined portion 32 side, toward the lower side, that is, the other end face portion 31 side. is formed in The inclined portion 33 is formed to have a larger diameter as the distance from the collar portion 27 increases. The diameter dimension of the inclined portion 33 on the small diameter side is equal to the diameter dimension of the non-inclined portion 32 . A flange portion 27 is positioned on the small diameter side of the inclined portion 33 . In the present embodiment, the inclined portion 33 is inclined at a constant or substantially constant angle with respect to the axial direction, but this angle may gradually change.

The ball stud 17 is made of steel or the like, for example, and includes a spherical ball portion 35 and a stud portion 36 that is a shaft-shaped shaft portion connected to the ball portion 35 at its lower end.

A portion of the outer peripheral surface of the ball portion 35 is slidably (rotatably) held by the bearing seat 18 via a lubricant. That is, the ball portion 35 is housed in the inner chamber 22 of the socket 16 together with the bearing seat 18 .

The stud portion 36 is a portion to which a load is applied by being connected to a member to be connected, which is an external mating member (not shown). The stud portion 36 protrudes from the ball portion 35 . The stud portion 36 is formed in a cylindrical shape. Also, the stud portion 36 is arranged coaxially with the ball portion 35 . That is, the central axis of the stud portion 36 is arranged so as to pass through the center of the ball portion 35 . The stud portion 36 is inserted through the opening portion 21 and the upper end side protrudes outward (upward in FIG. 1) from the socket 16 . That is, the stud portion 36 extends outside the socket 16 . The stud portion 36 may be formed integrally with the ball portion 35 from the same material as the ball portion 35, or may be formed from the same material as or different from the ball portion 35 and integrated with the ball portion 35 by welding or the like. may be Further, the stud portion 36 may be formed with a stud flange portion that forms an attachment seat surface with the member to be connected.

The bearing seat 18 is formed in a tubular shape (cylindrical shape) from, for example, synthetic resin having excellent abrasion resistance, and is housed in the inner chamber 22 of the socket 16 while being fitted and held.

The dust cover 19 is also called a dust seal or a boot, and covers the opening 21 of the socket 16 regardless of the swing of the ball stud 17 to prevent moisture, dust, etc. from entering the socket 16 or the bearing seat 18. It is something to do. The dust cover 19 is made of, for example, synthetic resin and has a substantially cylindrical shape. Further, the dust cover 19 has a flat shape in which the axial dimension is smaller than the diameter dimension. The dust cover 19 includes a cylindrical body portion 40, a small diameter side lip portion 41 as a first fixing portion fixed to the ball stud 17, and a large lip portion as a second fixing portion fixed to the socket 16. A radial side lip portion 42 is integrally provided. Lubricant (grease) is sealed inside the dust cover 19 .

The body portion 40 is formed such that the central portion in the vertical direction, which is the axial direction, bulges in the direction perpendicular to the axis with respect to both end portions.

The small diameter side lip portion 41 is a portion that is assembled to the stud portion 36 of the ball stud 17 . The small diameter side lip portion 41 is positioned so as to be continuous with the upper end portion, which is one end portion of the main body portion 40 . The small diameter side lip portion 41 is formed smaller in inner diameter dimension and outer diameter dimension than the large diameter side lip portion 42 . That is, the dust cover 19 is formed such that its upper end, which is one end, is smaller in diameter than its lower end, which is the other end.

The large diameter side lip portion 42 is a portion at least partially attached to the cover attachment portion 25 of the socket 16 and held with respect to the socket 16 . That is, the large diameter side lip portion 42 is a portion fixed to the outer peripheral side of the socket 16 . The large-diameter lip portion 42 is positioned so as to be continuous with the lower end portion, which is the other end portion of the main body portion 40 . The large-diameter lip portion 42 integrally includes a connecting portion 45 connected to the main body portion 40, a lip main body portion 46 connected to the connecting portion 45, and a folded portion 47 connected to the lip main body portion 46. , are folded back in a U-shape in the direction perpendicular to the axis. That is, a groove-shaped mounting portion 48 is formed on the outer side of the large diameter side lip portion 42 . An annular clip 49 as a fixing member is attached to the attachment portion 48 . A clip 49 fastens and fixes the large-diameter side lip portion 42 to the cover mounting portion 25 in the direction perpendicular to the axis.

The connecting portion 45 is a portion that faces the flange portion 27 . The connecting portion 45 is positioned outside the cover attachment portion 25 .

The lip body portion 46 is a portion that connects the connecting portion 45 and the folded portion 47 . The lip body portion 46 is formed in a cylindrical shape having a central axis along the axial direction. The lip body portion 46 is positioned inside the cover attachment portion 25 . A clip 49 is in close contact with the outer peripheral surface of the lip body portion 46 . The inner peripheral surface of the lip body portion 46 faces the inner wall surface of the cover attachment portion 25 and is in close contact with the inner wall surface. The lip body portion 46 has a first body portion 50 that is a non-tilt facing portion facing the non-tilt portion 32 and a second body portion 51 that is a tilt facing portion facing the tilt portion 33 . The first body portion 50 is a portion that continues with the connecting portion 45 . That is, the first body portion 50 forms the upper end side, which is one end side of the lip body portion 46 . The first body portion 50 is formed in a cylindrical shape with constant or substantially constant inner diameter and outer diameter. The first body portion 50 is in close contact with the non-inclined portion 32 . If the cover attachment portion 25 does not have the non-inclined portion 32, the first body portion 50 is not required. At least the inner side of the second main body portion 51 is gradually expanded from the first main body portion 50 on the one end side toward the folded portion 47 on the other end side. The second main body portion 51 is inclined in a shape equal to or substantially equal to that of the inclined portion 32 and is in close contact with the inclined portion 32 . The first body portion 50 and the second body portion 51 are positioned inside the clip 49, respectively. Therefore, the tightening force from the clip 49 acts across the first body portion 50 and the second body portion 51 .

Furthermore, a notch portion 53 is formed across the lip body portion 46 and the connecting portion 45 . The notch 53 is formed along the edge of the upper end of the socket 16, which is one end of the cover attachment portion 25. As shown in FIG. The cutout portion 53 is shaped so that the collar portion 27 is fitted from the upper end side, which is the one end side. That is, the notch portion 53 has a shape in which the lower corner portion of the flange portion 27 is fitted. The notch portion 53 is formed on the inner peripheral edge of the large diameter side lip portion 42 . The notch portion 53 is a stepped portion formed by notching in a rectangular shape. The cutout portion 53 has a first facing surface 56 that faces the side surface portion 55 that is the outer edge of the collar portion 27, and a second facing surface that faces one end surface portion 30 of the cover cutout portion 25 that is the end of the collar portion 27. a surface 57; The side surface portion 55 extends along a direction intersecting or perpendicular to the one end surface portion 30 . Therefore, the flange portion 27 has a sharp corner at the position where the side surface portion 55 and the one end surface portion 30 are connected. That is, at least the lower edge portion of the flange portion 27 on the cover attachment portion 25 side is a corner portion.

The first opposing surface 56 is a surface extending along the axial direction. The first opposing surface 56 is formed in the shape of a cylindrical inner surface having a constant or substantially constant diameter. The first opposing surface 56 extends to the upper end of the large diameter side lip portion 42 at the upper end side, which is the one end side. The first opposing surface 56 is in close contact with the side surface portion 55 of the collar portion 27 .

The second facing surface 57 is a surface extending along the direction perpendicular to the axis. That is, the second opposing surface 57 is a surface extending along a direction intersecting or perpendicular to the first opposing surface 56 . The second opposing surface 57 extends toward the central axis of the dust cover 19 or the large diameter side lip portion 42 with respect to the first opposing surface 56 . The second opposing surface 57 continues to the lower end side, which is the other end side of the first opposing surface 56 . The wall surface of the notch 53 is formed in a crank shape by the first opposing surface 56 and the second opposing surface 57 . The second facing surface 57 is in close contact with the one end surface portion 30 .

An absorbing portion 59 is formed in the lip main body portion 46 . The absorbing portion 59 is a recess provided at a position facing the inclined portion 33 of the cover mounting portion 25 . The absorbing portion 59 is formed in the lip body portion 46 . In this embodiment, the absorbent portion 59 is formed across the first body portion 50 and the second body portion 51 . That is, the absorbing portion 59 is formed in the cover mounting portion 25 so as to face the position where the non-inclined portion 32 and the inclined portion 33 are connected. The absorbing portion 59 is positioned across the non-inclined portion 32 and the inclined portion 33 so as to face each other. The absorbing portion 59 is positioned on the inner surface side of the lip body portion 46 . Therefore, the absorbing portion 59 is positioned inside the clip 49 . Moreover, the absorbing portion 59 is formed to have a semicircular cross section in the present embodiment. The absorbing portion 59 is formed continuously over the entire circumference of the dust cover 19 . The absorbing portion 59 reduces the thickness of the lip body portion 46 in the direction perpendicular to the axis. At the position of the absorbing portion 59, the lip main body portion 46 or the large diameter side lip portion 42 is positioned away from the cover mounting portion 25 at least in the axial direction. In addition, the absorbing portion 59 is located below the notch portion 53 at a distance.

The folded portion 47 is a portion facing the other end surface portion 31 of the cover attachment portion 25 . The folded portion 47 extends from the lower end portion, which is the other end portion of the lip body portion 46, along the direction perpendicular to the axis. The folded portion 47 is axially separated from the connecting portion 45 and faces the connecting portion 45 . In addition, the folded portion 47 extends outward from the cover mounting portion 25 on the tip end side.

The large-diameter side lip portion 42 is in close contact with the cover mounting portion 25, the flange portion 27, and the clip 49, except for the absorbing portion 59. , each shown with a gap.

Next, the operation of one embodiment will be described.

When the dust cover 19 is attached over the socket 16 and the stud portion 36 of the ball stud 17, the small diameter side lip portion 41 is pressed against the outer peripheral surface of the stud portion 36, and the large diameter side lip portion 42 is attached to the cover of the socket 16. It is positioned at portion 25 and is clamped and fixed by clip 49 .

The large-diameter side lip portion 42 is fitted with a corner portion where the side portion 55 of the collar portion 27 of the socket 16 and the one end surface portion 30 are connected to the position of the notch portion 53, and the first opposing surface 56 is connected to the side portion 55. The second opposing surface 57 is brought into close contact with the one end face portion 30. As shown in FIG.

In addition, the lip body portion 46 of the large-diameter side lip portion 42 is in close contact with the inner wall surface of the cover mounting portion 25 , and the folded portion 47 is in close contact with the other end face portion 31 . The first body portion 50 of the lip body portion 46 is in close contact with the non-inclined portion 32 of the cover mounting portion 25 , and the second body portion 51 is in close contact with the inclined portion 33 of the cover mounting portion 25 . Furthermore, the absorbing portion 59 is recessed away from the inner wall surface of the cover mounting portion 25 .

At this time, the tightening force of the clip 49 directed toward the central axis in the axial direction is smaller at the upper side where the diameter is larger than the lower side where the diameter is large at the portion where the inclined portion 33 and the second main body portion 51 are in close contact with each other. Further, in the present embodiment, the clamping force directed toward the central axis in the axial direction by the clip 49 is applied to the non-inclined portion 32 and the first main body portion 50 at the contact portion between the inclined portion 33 and the second main body portion 51. smaller than the contact part of Therefore, the large diameter side lip portion 42 moves from the second main body portion 51 side to the first main body portion 50 side, that is, from the lower end side, which is the other end side, to the upper end side, which is the one end side, that is, the cover mounting portion 25. A force in the axial direction tends to shift toward the flange 27 forming the edge on the one end side. In the large-diameter side lip portion 42, the notch portion 53 prevents the collar portion 27 at the edge portion on the upper end side of the cover attachment portion 25 from being strongly abutted. In the present embodiment, notch 53 stably receives flange 27 by contacting flange 27 on two surfaces, ie, first opposing surface 56 and second opposing surface 57 .

In the ball joint 11, when a load from the vehicle body is applied to the ball stud 17, the ball stud 17 swings in the left-right direction. As the dust cover 19 deforms following this rocking movement, the connection portion 45 of the large diameter side lip portion 42 connected to the main body portion 40 is pressed against the flange portion 27 in the axial direction or the axial direction, and the reaction force is applied. are received by the first opposing surface 56 and the second opposing surface 57 of the notch 53, and stress concentration at the corners of the flange 27 is dispersed.

As described above, according to one embodiment, the notch 53 is formed along the edge of the large-diameter lip 42 on the one end side of the cover mounting portion 25 in the socket 16, that is, along the collar 27, thereby Due to contact with the inclined portion 33 of the inner wall surface of the mounting portion 25, the edge of the cover mounting portion 25 on one end side shifts from the lower side, which is the other end side in the axial direction, to the upper side, which is the one end side. The stress generated in the large-diameter side lip portion 42 due to contact with the collar portion 27 can be dispersed.

In particular, the notch 53 is formed by a first facing surface 56 extending along the axial direction and a second facing surface 57 extending along the direction perpendicular to the axis, so that the edge of the upper end side of the cover mounting portion 25 is formed. The stress generated in the large-diameter side lip portion 42 can be efficiently dispersed by contacting the flange portion 27 on the side from the mutually intersecting directions.

Therefore, it is possible to suppress material fatigue due to repeated rocking motions of the ball stud 17, improve durability without increasing the thickness of the dust cover 19, and suppress or prevent problems such as breakage. Since it is not necessary to increase the thickness of the dust cover 19, the dust cover 19 does not become difficult to deform, and the rocking of the ball stud 17 is not easily hindered by the dust cover 19, and the dust cover 19 follows the rocking of the ball stud 17. In addition, it is possible to effectively suppress or prevent the entry of water mud, dust, etc. into the opening 21 .

Furthermore, since the absorbing portion 59 recessed at a position facing the inclined portion 33 of the cover mounting portion 25 of the large diameter side lip portion 42 is positioned between the clip 49 and the inner wall surface of the cover mounting portion 25, the clip 49 The tightening force is absorbed by the deformation at the absorbing portion 59 . Therefore, for example, in the case of a configuration without the absorber 59, the clamping force in the axial direction by the clip 49 is all transmitted to the cover mounting portion 25 via the large diameter side lip portion 42 and directly acts as a reaction force. In the embodiment, the absorbing portion 59 uses the clamping force in the axial direction by the clip 49 to deform the large diameter side lip portion 42, that is, to crush the absorbing portion 59. pressure on the cover mounting portion 25 is reduced. Therefore, as the inclination of the inclined portion 33 causes the large diameter side lip portion 42 to move from the lower side, which is the other end in the axial direction, to the upper side, which is the one end in the axial direction, becomes smaller. It is possible to suppress the displacement of the large diameter side lip portion 42 from the lower side to the upper side due to contact with the inclined portion 33 of the inner wall surface. Therefore, the stress generated in the large-diameter side lip portion 42 due to contact with the edge portion on the one end side of the cover mounting portion 25, that is, the flange portion 27 can be further suppressed, so that the reaction force from the socket 16 (flange portion 27) can also be suppressed. Problems such as breakage can be suppressed or prevented.

By providing the dust cover 19, the ball joint 11 having excellent durability against repeated swinging of the ball stud 17 can be provided.

It should be noted that in the above embodiment, the ball joint 11 is not limited to use in automobiles or vehicles, and may be used in any other device.

INDUSTRIAL APPLICABILITY The present invention can be suitably used, for example, as a ball joint for a steering system or a suspension system of a vehicle such as an automobile, and a dust cover therefor.

11 ball joint
16 Socket, which is a receiving member
17 Ball stud which is a ball-side member
19 dust cover
25 Cover mount
33 Slope
35 ball part
36 Stud
40 Body
42 Large-diameter side lip, which is the lip
51 the second body portion which is the inclined facing portion
53 Notch
59 Absorber

Claims (2)

Cylindrical shape having a groove-shaped cover mounting portion recessed in the axial direction on the outer side, and an inclined portion expanding from one end side to the other end side in the axial direction on at least a part of the inner wall surface of the cover mounting portion a receiving side member, a ball portion rotatably held by the receiving side member, and a ball side member including a stud portion projecting from the ball portion and extending to the outside of the receiving side member On the other hand, a dust cover of a ball joint mounted over the cover mounting portion of the receiving side member and the stud portion of the ball side member,
a cylindrical main body;
a lip portion provided at an end portion in the axial direction of the body portion, at least a portion of which is attached to the cover attachment portion;
The lip portion is inclined in a shape equal to or substantially equal to that of the inclined portion and is in close contact with the notched portion formed along the edge of one end of the cover mounting portion of the receiving-side member. and an absorbing portion recessed in the inclined facing portion ,
The notch portion is a stepped portion formed by notching in a quadrangular shape at the inner peripheral edge of the lip portion.
A ball joint dust cover characterized by : Cylindrical shape having a groove-like cover mounting portion recessed in the axial direction on the outer side, and an inclined portion expanding from one end side to the other end side in the axial direction on at least a part of the inner wall surface of the cover mounting portion. a receiving member of
a ball-side member including a ball portion rotatably held by the receiving-side member and a stud portion projecting from the ball portion and extending to the outside of the receiving-side member;
A ball joint comprising: a dust cover according to claim 1 , which is attached across the cover attachment portion of the receiving side member and the stud portion of the ball side member.

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