JP2006292094A - Ball joint and its bearing seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing seat of a ball joint which is enhanced in durability, cushioning performance and spherical lubricating property. <P>SOLUTION: An annular peripheral groove 46 and slits 45 intersecting the peripheral groove 46 are formed in a sliding surface 53 for rotatably supporting a ball section of a ball stud. As a result, the flexibility of the ball seat 4 is improved so that the sliding surface 53 uniformly comes into contact with an outer peripheral surface of the ball section, thereby enhancing the durability and cushioning performance. Further, since lubricant is fed around the outer peripheral surface of the ball section by the peripheral groove 46 and the slits 45, the spherical lubricating property can be improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cylindrical ball joint having a sliding surface that rotatably holds a substantially spherical ball portion of a ball stud via a lubricant, and a bearing seat thereof.

  2. Description of the Related Art Conventionally, for example, a ball joint used for a suspension device or a steering device of an automobile has a substantially bottomed cylindrical socket having an inner chamber with an opening, and is fixed to the inner chamber of the socket and communicates with the opening. A ball seat as a bearing seat having an opening to be opened, a ball portion that comes into contact with a sliding surface in the ball seat and is slidably held via a lubricant, and a stud portion that is inserted into the opening and the opening portion And a ball stud having.

And as a ball seat of such a ball joint, in order to reduce the contact area to the ball part to suppress the operating torque and improve the spherical lubricity of the ball part, the groove part is circumferentially arranged along the axial direction. There are known a plurality of devices that are spaced apart. Such a ball seat is elastically deformed along the outer peripheral surface of the ball portion by fitting the retaining ring to the outer peripheral surface of the opening side while being accommodated in the inner chamber of the socket, and the ball portion is subjected to a predetermined operating torque. And fixed to the inner chamber of the socket by caulking and deforming the outer peripheral surface on the opening side of the socket (see, for example, Patent Document 1).
JP 2001-304239 A (page 2-3, FIG. 2 and FIG. 6)

  However, in the above-described ball seat, only a plurality of grooves along the axial direction are provided on the sliding surface. Therefore, when the ball sheet is fixed to the socket, the ball seat is interposed between the sliding surface and the outer peripheral surface of the ball portion. Although a continuous space is formed in the axial direction in which the groove is provided, only an intermittent space is formed only at the location of the groove in the circumferential direction intersecting the axial direction. For this reason, the contact state between the sliding surface and the outer peripheral surface of the ball portion is different between the axial direction and the circumferential direction, and the sliding surface and the outer peripheral surface of the ball portion cannot be uniformly contacted. There is a problem that the lubricity cannot be said to be sufficient.

  This invention is made | formed in view of such a point, and it aims at providing the ball joint which improved durability, cushioning property, and spherical lubricity, and its bearing seat.

  The ball seat of the ball joint according to claim 1, wherein at least a part of the bearing seat is in contact with the outer peripheral surface of the substantially spherical ball portion of the ball stud, and the ball portion is rotatably held via a lubricant. A ball joint bearing seat comprising a moving surface and an opening formed at one end, and accommodated in a socket having an opening so that the opening communicates with the opening. An annular groove portion provided and a slit provided in a direction intersecting with the groove portion are provided.

  Then, an annular groove is formed on the sliding surface that at least partially contacts the outer peripheral surface of the ball portion of the ball stud and rotatably holds the ball portion, and a slit is formed in a direction intersecting the groove portion. As a result, the flexibility is improved and the sliding surface contacts the outer peripheral surface of the ball portion uniformly, and the durability and cushioning properties are improved, and the groove and the slit spread the lubricant to the outer peripheral surface of the ball portion. The spherical lubricity is improved.

  The ball joint bearing sheet according to claim 2 is the ball joint bearing sheet according to claim 1, wherein a plurality of slits are radially provided on the sliding surface.

  By providing a plurality of slits radially on the sliding surface, the axial contact area between the sliding surface and the outer peripheral surface of the ball portion is further reduced, and the operating torque is further suppressed.

  The ball joint according to claim 3 is a socket provided with an opening, the bearing seat according to claim 1 or 2 provided in the socket, and rotatably held in the bearing seat via a lubricant. And a ball portion accommodated in the socket, and a ball stud provided with a stud portion protruding from the ball portion and inserted through the opening of the bearing seat.

  Further, by providing the ball joint bearing sheet according to claim 1 or 2 in which the cushioning property and the spherical lubricity are improved, the bendability of the bearing sheet is improved by the groove and slit provided in the sliding surface, and the sliding surface. As a result, the ball portion is smoothly rotated and the stable characteristics can be obtained.

  According to the ball joint bearing sheet according to claim 1, by forming an annular groove on the sliding surface and forming a slit in a direction intersecting with the groove, the flexibility is improved and the outer periphery of the ball is increased. The sliding surface can be in uniform contact with the surface and durability and cushioning can be improved, and the lubricant can spread over the outer peripheral surface of the ball portion by the groove and slit, thereby improving spherical lubricity.

  According to the ball joint bearing sheet according to claim 2, in addition to the effect of the ball joint bearing sheet according to claim 1, by providing a plurality of slits radially on the sliding surface, the sliding surface and the ball portion The contact area in the axial direction with the outer peripheral surface can be further reduced, and the operating torque can be further suppressed.

  According to the ball joint according to claim 3, by providing the ball joint bearing sheet according to claim 1 or 2 which can improve the cushioning property and the spherical lubricity, the groove of the bearing surface and the slit are provided on the sliding surface. Flexibility is improved so that the contact of the sliding surface with the ball portion is improved, durability is improved, and the ball portion is smoothly rotated to obtain stable characteristics.

  Hereinafter, the configuration of an embodiment of the present invention will be described with reference to FIGS.

  In FIG. 3, 1 is a ball joint, and this ball joint 1 is used for, for example, a suspension device or a steering device of an automobile. The ball joint 1 includes a ball stud 2 made of steel, a substantially cylindrical socket 3 made of metal, a substantially cylindrical ball sheet 4 made of synthetic resin as a bearing seat, and rubber or soft synthetic. A dust cover (not shown) formed in a substantially cylindrical shape with resin or the like is provided.

  The ball stud 2 includes a ball portion 15 that is rotatably held by the ball seat 4 and a stud portion 16 that protrudes from the ball portion 15.

  The ball portion 15 is accommodated in the socket 3 while being rotatably held by the ball seat 4. The stud portion 16 protrudes from the socket 3 in the shape of a shaft.

  Further, the socket 3 includes an inner chamber 21 in which the ball seat 4 is fitted, and an opening 22 communicating with the inner chamber 21 is formed at one end in the axial direction. A dust cover attachment groove 23 to which the cover is attached is formed in a concave shape, and a bottom opening 25 closed by a substantially disc-shaped plug 24 is formed in the other end side in the axial direction.

  The inner chamber 21 is reduced in diameter on the opening 22 side, and one end side in the axial direction of the ball seat 4 fitted in the inner chamber 21 is reduced in diameter along this reduced diameter shape so that the ball portion of the ball stud 2 is formed. Curved along 15.

  The opening 22 is a portion through which the stud portion 16 of the ball stud 2 is inserted, and is formed so as to increase in diameter toward the side opposite to the inner chamber 21.

  Further, the dust cover mounting groove 23 is provided in an annular shape on the outer peripheral surface of the socket 3, and one end portion of the dust cover is a portion that is tightened and fitted by a metal clip (not shown).

  The plug 24 has a disk-shaped plug body 27 and a recessed portion 28 formed in a recessed shape at the center of the plug body 27.

  The plug body 27 is fitted with a peripheral edge portion in a stepped portion 29 provided on the bottom opening 25 side of the inner chamber 21 of the socket 3, and in this fitted state, the other end side in the axial direction of the socket 3, that is, the bottom opening portion. The plug 24 is fixed to the socket 3 by caulking and deforming the outer peripheral surface of the 25 side in the direction of the central axis, the ball seat 4 is held in the inner chamber 21, and the ball stud is secured to the socket 3 and the ball seat 4. 2 is retained.

  Further, the concave portion 28 has a surface on the inner chamber 21 side serving as a bottom surface of the socket 3, and protrudes on the opposite side to the inner chamber 21 in a state where the plug 24 is attached to the socket 3. The other end abuts.

  As shown in FIGS. 1 and 2, the ball sheet 4 is formed of a synthetic resin such as flexible polyacetal, and has a substantially cylindrical sheet body in which an opening 31 is formed on one end side in the axial direction. 32, and a diameter-reduced portion 33 that protrudes from the other end in the axial direction of the seat body 32, that is, an end opposite to the opening 31, and that is slanted along the outer peripheral surface of the ball seat 4, The sheet main body 32 has a protruding portion 34 protruding from the other end side in the axial direction.

  The opening 31 communicates with the opening 22 in a state where the ball seat 4 is held in the inner chamber 21 of the socket 3, and is a portion through which the stud portion 16 of the ball stud 2 is inserted.

  The seat body 32 is a portion where the outer peripheral surface is in contact with the inner peripheral surface of the inner chamber 21 of the socket 3, and the ball portion of the ball stud 2 with the ball seat 4 fitted to the inner chamber 21 on the opening 31 side. Deforms along 15 outer peripheral surface. Then, on the inner peripheral surface of the seat main body 32, an opening side sliding contact surface portion 36 that comes into sliding contact with the outer peripheral surface of the ball portion 15 by deformation of the seat main body 32, and the opening side sliding contact surface portion 36 that is continuous with the opening side sliding contact surface portion 36 are provided. The equator sliding contact surface portion 37 that is slidably contacted in the vicinity of the equator of the outer peripheral surface, that is, in the vicinity of the position where the radius of the ball portion 15 is maximized on the plane orthogonal to the central axis of the ball stud 2, is continuous with the equator sliding contact surface portion 37. A separation surface portion 38 that is separated from the outer peripheral surface of the ball portion 15 and a step surface portion 39 that is continuous with the separation surface portion 38 and extends in the central axis direction are formed concentrically in plan view.

  The opening-side slidable contact surface portion 36 is formed in a cylindrical inner peripheral surface shape, and extends from the opening 31 to the central region in the axial direction of the sheet main body 32.

  Further, the equator sliding contact surface portion 37 is curved in a spherical shape along the outer peripheral surface of the ball portion 15, and the diameter of the separation surface portion 38 side is slightly reduced with respect to the opening side sliding contact surface portion 36 side.

  Further, the separation surface portion 38 is formed in a cylindrical inner peripheral surface shape, and the step surface portion 39 is formed in an annular plane shape, and as shown in FIG. 3, the separation surface portion 38 and the step surface portion 39 and the ball stud 2 ball. Between the outer peripheral surface of the portion 15, a lubricant reservoir 40 for accommodating a lubricant (not shown) such as grease is defined.

  On the other hand, the diameter-reduced portion 33 has the end opposite to the seat body 32 in contact with the inner chamber 21 side surface of the concave portion 28 of the plug 24 in a state where the ball seat 4 is fitted in the inner chamber 21 of the socket 3. A space portion 41 is formed between the outer peripheral surface, the plug 24, and the protruding portion 34. Further, on the inner peripheral surface of the reduced diameter portion 33, as shown in FIGS. 1 and 2, a reduced diameter sliding surface portion 42 continuing to the stepped surface portion 39 and an inclined surface portion continuing to the reduced diameter sliding surface portion 42. 43 and a bottom surface portion 44 that continues to the inclined surface portion 43 and extends in the central axis direction are formed concentrically in a plan view, and a plurality of, for example, three slits 45 are provided.

  The space portion 41 is an annular space that is continuous with the entire outer peripheral surface of the reduced diameter portion 33, and can absorb the flexible deformation of the reduced diameter portion 33 in the axial direction.

  The reduced diameter sliding surface portion 42 is curved in a spherical shape along the outer peripheral surface of the ball portion 15 of the ball stud 2. That is, the reduced diameter sliding surface portion 42 is positioned on a virtual extension line obtained by extending the spherical shape of the equator sliding contact surface portion 37 toward the reduced diameter portion 33 side. In addition, the reduced diameter sliding surface portion 42 is provided with an annular circumferential groove 46 as a groove portion intersecting with each of the slits 45 in a substantially central region in the axial direction.

  The circumferential groove 46 is a portion that holds a lubricant (not shown) inside, and intersects the axial direction of the ball seat 4, for example, a direction parallel to the equator direction of the ball portion 15 that is a direction orthogonal to the ball seat 4. And is continuous over the entire circumference. The reduced diameter sliding surface portion 42 is divided into a first sliding surface portion 48 continuous with the stepped surface portion 39 and a second sliding surface portion 49 continuous with the inclined surface portion 43 by the circumferential groove 46.

  Further, the inclined surface portion 43 is separated from the ball portion 15 of the ball stud 2 and is reduced in diameter toward the bottom surface portion 44 side.

  The bottom surface portion 44 is separated from the ball portion 15 of the ball stud 2 and faces the bottom surface of the ball portion 15. A substantially circular bottom opening 51 is formed at a substantially central portion of the bottom surface portion 44. The bottom opening 51 holds the lubricant between the bottom opening 51 and the concave portion 28 of the plug 24. Then, as shown in FIG. 3, the lubricant reservoir space 52 is partitioned from the ball portion 15 by the inclined surface portion 43, the bottom surface portion 44, and the bottom portion opening 51.

  2, each slit 45 is formed along a predetermined direction, for example, a direction perpendicular to the equator which is the meridian direction of the ball portion 15, that is, along the axial direction of the reduced diameter portion 33 shown in FIG. They are radially spaced apart from each other at substantially equal angles in the circumferential direction, and continue linearly from the reduced-diameter sliding surface portion 42 to the bottom opening 51. That is, each slit 45 is located on the outer peripheral surface side opposite to the stud portion 16 with respect to the equator of the ball portion 15 and is formed so as to be substantially orthogonal to the circumferential groove 46.

  Further, these slits 45 are provided through the ball sheet 4 in the thickness direction. For this reason, each of the reduced diameter portions 33 located between the slits 45 has a flap piece shape.

  As shown in FIGS. 1 and 2, a spherical sliding surface 53 along the outer peripheral surface of the ball portion 15 is formed by the opening-side sliding contact surface portion 36, the equator sliding contact surface portion 37, and the reduced diameter sliding surface portion 42. Is formed.

  Further, as shown in FIG. 3, the protruding portion 34 is a portion that abuts against the plug body 27 of the plug 24 in a state where the ball seat 4 is fitted in the inner chamber 21 of the socket 3.

  Next, the assembly operation of the above embodiment will be described.

  First, the ball portion 15 of the ball stud 2 is held in the ball seat 4 into which lubricant is injected, and the stud portion 16 protrudes from the opening 31, and the stud portion 16 of the ball stud 2 is projected from the bottom opening portion 25 of the socket 3. The ball seat 4 is inserted into the inner chamber 21 of the socket 3 by inserting the side. Alternatively, a lubricant is applied to the ball portion 15, and the ball portion 15 to which this lubricant is applied is inserted into the ball seat 4 and mounted in the inner chamber 21 of the socket 3. In this state, the stud 16 is inserted through the opening 22 and protrudes to the outside.

  Next, the peripheral portion of the plug body 27 of the plug 24 is fitted into the stepped portion 29 and the outer peripheral surface of the socket 3 on the bottom opening 25 side is caulked and deformed in the central axis direction, whereby the ball stud 2 and the ball seat 4 are formed. It is held in the socket 3.

  At this time, the circumferential groove 46 and the slits 45 formed so as to intersect with the circumferential groove 46 are pressed by the plug 24 when the ball sheet 4 is fitted, so that the tightening allowance is made in the axial direction of the ball sheet 4. The flexibility of the reduced-diameter portion 33 of the ball seat 4 when applied is improved so that the sliding surface 53 is in uniform contact with the outer peripheral surface of the ball portion 15 and durability and cushioning can be improved. Since the lubricant is distributed to the outer peripheral surface of the ball portion 15 in the weft direction and the entire warp direction by the 46 and the slit 45, the spherical lubricity can be improved.

  Moreover, since the slits 45 are continuous with each other at the bottom opening 51, the lubricant can be more reliably spread over the entire outer peripheral surface of the ball portion 15.

  Further, since each slit 45 penetrates the ball sheet 4 in the thickness direction, the reduced diameter portion 33 located between the slits 45 is formed in a flap piece shape, so that a groove portion is provided instead of the slit 45. Further, the flexibility of the reduced diameter portion 33 can be further improved.

  Further, since the lubricant spreads over the entire outer peripheral surface of the ball portion 15 and the contact area between the ball portion 15 and the sliding surface 53 is reduced by the slit 45 and the circumferential groove 46, the torque of the ball stud 2 can be relaxed.

  Then, by providing a plurality of slits 45 on the sliding surface 53 that are spaced apart in the circumferential direction, the axial contact area between the sliding surface 53 and the outer peripheral surface of the ball portion 15 can be further reduced, and the torque can be further relaxed.

  Further, the lubricant reservoir 40 is defined by the separation surface 38 and the stepped surface 39 of the ball seat 4, and the lubricant reservoir space 52 is defined by the inclined surface 43, the bottom 44 and the bottom opening 51, thereby providing lubrication. The agent can be securely held, the axial contact area between the sliding surface 53 and the outer peripheral surface of the ball portion 15 can be further reduced, and the torque can be further relaxed.

  By using such a ball sheet 4 for the ball joint 1, the reduced diameter sliding is achieved by improving the flexibility of the reduced diameter portion 33 by the slit 45 and the circumferential groove 46 provided in the reduced diameter sliding surface portion 42. The contact of the surface portion 42 with the ball portion 15 can be improved, the durability of the ball joint 1 can be improved, and the ball portion 15 of the ball stud 2 can be smoothly rotated to obtain stable characteristics.

  Further, the bottom portion of the reduced diameter portion 33 abuts on the concave portion 28 of the plug 24, and the protruding portion 34 abuts on the plug body 27 of the plug 24, so that the space between the reduced diameter portion 33, the protruding portion 34, and the plug 24 By forming the portion 41, the flexible deformation of the reduced diameter portion 33 with respect to the axial load of the ball stud 2 can be absorbed by the space portion 41, and the strength against the axial load can be improved.

  In the above embodiment, the number of the slits 45 and the circumferential grooves 46 can be arbitrarily set.

  Further, either one of the slit 45 and the circumferential groove 46 is formed along a direction having a meridian direction component of the ball portion 15, and one of the other is formed along a direction intersecting either one. For example, the forming direction is not limited.

  Further, the shape of the sliding surface 53 of the ball seat 4 can be arbitrarily set except for the slit 45 and the circumferential groove 46.

  The slit 45 and the circumferential groove 46 can be provided at any position on the sliding surface 53, such as the opening-side sliding surface portion 36 and the equator sliding contact surface portion 37 side.

  Further, the details of the ball joint 1 are not limited to the above configuration.

It is a longitudinal cross-sectional view which shows the bearing seat of the ball joint of one embodiment of this invention. It is a top view which shows the bearing seat of a ball joint same as the above. It is a longitudinal cross-sectional view which shows the ball joint provided with the bearing seat of the ball joint same as the above.

Explanation of symbols

1 Ball joint 2 Ball stud 3 Socket 4 Ball seat as bearing seat
15 Ball part
16 Stud section
22 opening
31 opening
45 slit
46 Circumferential groove as groove
53 Sliding surface

Claims (3)

A spherical sliding surface that at least partly contacts the outer peripheral surface of the substantially spherical ball portion of the ball stud and rotatably holds the ball portion via a lubricant, and an opening formed at one end. A ball joint bearing seat accommodated in a socket having an opening so that the opening communicates with the opening,
An annular groove provided on the sliding surface;
A ball joint bearing sheet comprising a slit provided in a direction intersecting the groove. The ball joint bearing sheet according to claim 1, wherein a plurality of slits are provided radially on the sliding surface. A socket with an opening,
The bearing seat according to claim 1 or 2 provided in the socket;
A ball portion rotatably held in the bearing seat via a lubricant and accommodated in the socket, and an opening of the bearing seat projecting from the ball portion and a stud portion inserted through the opening portion A ball joint characterized by comprising:

Images