JP2011179672A - Method for manufacturing ball joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a ball joint that can freely set the radial dimension of a collar part and secure quality without degrading manufacturability. <P>SOLUTION: A ball part 41 is inserted in a socket body 21 from a second socket opening 26 of the socket body 21. A stud part 42 formed with the collar part 46 is welded to the ball part 41 from the first socket opening 25 side of the socket body 21. Since the collar part 46 is not inserted in the respective openings 25, 26, the radial dimension of the collar part 46 can be freely set regardless of the radial dimensions or the like of the respective openings 25, 26. Since a process for separately assembling the collar part 46 to the stud part 42 is dispensed with, manufacturability is not degraded. Further, since it is not necessary to carry out caulking deformation of the first socket opening 25 side of the socket body 21, quality can be secured such as stabilization of the radial dimension and torque. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for manufacturing a ball joint including a ball stud having a flange projecting around a stud.

  Conventionally, this type of ball joint includes a cylindrical socket, a ball seat assembled inside the socket, a ball portion rotatably held by the ball seat, and a stud portion protruding from the ball portion. And a dust cover assembled between the socket and the ball stud. The stud portion of the ball stud protrudes to the outside of the socket, and the stud portion is formed with a screw portion fastened to the mounted member on the distal end side, and a position on the proximal end side of the screw portion. In addition, a flange portion that forms a fastening seat surface with the attached member is formed.

  As a manufacturing method of such a ball joint, for example, a ball stud holding a ball portion is inserted into a ball seat from one opening portion having a relatively large diameter formed on one end side of a socket, and this ball stud The stud portion side of the socket is inserted into the other opening portion having a relatively small diameter formed on the other end side of the socket, and the ball stud is fixed together with the ball seat by closing one opening portion with a plug. It is known (for example, see Patent Document 1).

  As another method for manufacturing the ball joint as described above, for example, a ball stud holding a ball portion on a ball seat is press-fitted into a bottomed cylindrical socket from the opening portion, and the peripheral edge portion of the socket opening portion is caulked. A method of deforming and fixing a ball stud together with a ball sheet is known (for example, see Patent Document 2).

JP 2004-36700 A (page 4, FIG. 2) Japanese Patent Laying-Open No. 2006-312948 (page 7, FIG. 1)

  However, particularly in the case of a ball joint used as a stabilizer link, which is a connecting device for connecting a suspension arm and a stabilizer of a suspension device (suspension device) of a vehicle such as an automobile, a fastening seat surface (fastening force) is secured. In order to do so, it is required to increase the diameter of the collar.

  In such a case, in the ball joint manufacturing method described in Patent Document 1 described above, since the flange portion is inserted into the opening portion of the socket, the diameter dimension of the flange portion cannot be set to be equal to or larger than the diameter dimension of the socket opening portion. There is a problem in that there is a restriction on the diameter of the collar.

  In this regard, although it is conceivable to weld the flange portion to the stud portion in a subsequent process, in such a case, a separate step of forming the flange portion is necessary, and the productivity is lowered.

  Moreover, in the manufacturing method of the ball joint described in Patent Document 2 described above, since the diameter dimension of the flange part and the diameter dimension of the opening part of the socket are not directly related, the diameter dimension of the flange part can be set relatively freely. Because the socket opening is directly caulked and deformed, the diameter of the socket opening after caulking or the torque of the ball joint may not be stable due to the influence of deformation of the ball seat, etc. There's a problem.

  The present invention has been made in view of such points, and an object of the present invention is to provide a ball joint manufacturing method capable of freely setting the diameter dimension of the collar portion and ensuring the quality without deteriorating the manufacturability. To do.

  A ball joint manufacturing method according to claim 1, wherein a cylindrical socket body having one opening at one end and the other opening larger than the one opening at the other end, and the socket A socket having a closing member that closes the other opening of the main body, and a diameter of the socket that is rotatably held inside the socket main body of the socket is smaller than that of the other opening. A ball joint comprising: a large spherical ball portion; and a ball stud having a flange portion and a shaft stud portion projecting from the ball portion and projecting to the outside on the one opening side of the socket body. In the manufacturing method, an insertion step of inserting the ball portion into the socket body from the other opening of the socket body, and before the insertion into the socket body Relative to the ball portion, the stud portion is obtained by and a welding step of welding from the one opening side of the socket body.

  The ball joint manufacturing method according to claim 2 is the ball joint manufacturing method according to claim 1, wherein in the welding step, a part of the ball portion inserted into the socket body is removed from one opening of the socket body. The stud portion is protruded to the outside, and the stud portion is welded to the ball portion from the one opening side of the socket body at the protruding position.

  According to a third aspect of the present invention, in the ball joint manufacturing method according to the first or second aspect, the ball portion and the stud portion are formed of different materials.

  According to the ball joint manufacturing method of claim 1, the ball portion is inserted into the socket body from the other opening of the socket body, and the stud portion having the flange portion formed on the ball portion, By welding from one opening side of the socket body, the collar is not inserted into each opening, so the diameter of the collar can be set freely regardless of the diameter of each opening, etc. Since the process of assembling the flange part separately from the stud part is not required, the productivity is not lowered, and it is not necessary to caulk and deform one opening side of the socket body. The quality can be ensured, for example, the dimensions and torque can be stabilized.

  According to the method for manufacturing a ball joint according to claim 2, in addition to the effect of the method for manufacturing a ball joint according to claim 1, a part of the ball portion inserted into the socket main body is inserted into one opening of the socket main body. Even if spatter is generated during welding by welding the stud part to the ball part from one opening side of the socket body at the projected position, the spatter is Therefore, the quality of the socket can be ensured, and a process such as removal of spatter attached to the socket body is not required, thereby improving the productivity.

  According to the method for manufacturing a ball joint according to claim 3, in addition to the effect of the method for manufacturing a ball joint according to claim 1 or 2, the ball portion and the stud portion are formed of different materials from each other. The stud and the stud portion can be made of materials suitable for each, and the characteristics can be improved and the cost can be reduced.

It is a longitudinal cross-sectional view which shows the manufacturing method of the ball joint of one embodiment of this invention in order of (a) thru | or (c). It is a longitudinal cross-sectional view which shows a ball joint same as the above.

  The configuration of an embodiment of the present invention will be described below with reference to FIGS.

  In FIG. 2, reference numeral 11 denotes a ball joint. The ball joint 11 is a connecting device for connecting a suspension arm (attached member) and a stabilizer (attached member) of a suspension device (suspension device) of a vehicle such as an automobile. It is used as a stabilizer link or the like.

  The ball joint 11 includes a socket 16 that is a housing, a ball sheet 17 that is a bearing seat accommodated in the socket 16, and a part of the ball seat 17 that is slidably (rotatably) held. And a dust cover 19 which is a dust-proof member disposed from the outer peripheral surface of the socket 16 to the outer peripheral surface of the ball stud 18.

  The socket 16 has a cylindrical socket body 21 made of metal or the like, and a plug 22 as a disk-like closing member made of metal or the like that is integrally fixed to the socket body 21.

  The socket main body 21 has an inner chamber 24 for accommodating the ball seat 17 inside, and one opening (the upper end portion in FIG. 2) has one opening that communicates the inner chamber 24 with the outside of the socket main body 21. A first socket opening 25 that is a small opening as a part, and a large opening as the other opening that communicates with the outside of the socket body 21 at the other end (the lower end in FIG. 2). A second socket opening 26 which is an opening is provided. Further, the socket body 21 is formed with a cover fixing groove 28 in the circumferential direction for fixing the end of the dust cover 19 on the outer peripheral surface on one end side (the upper end side in FIG. 2). Further, the socket body 21 is formed with a protruding portion 31 protruding in the central axis direction at a continuous portion between the inner chamber 24 and the first socket opening 25, and the inner chamber 24 and the second socket opening 26. A holding portion 32 for holding the plug 22 is formed in a stepped shape at the continuous portion. The socket body 21 is fixed to the socket 16 by fixing the plug 22 by caulking and deforming the other end side (the lower end side in FIG. 2) of the holding portion 32. This is a caulking fixing portion 33 which is a fixing portion for fixing to the head. The socket body 21 is formed by, for example, (cold) forging or casting.

  The first socket opening 25 is formed so as to gradually increase in diameter from the protruding portion 31 side that sets the diameter dimension D1 toward one end side (the upper end side in FIG. 2).

  The second socket opening 26 has a diameter substantially equal to that of the inner chamber 24, and the diameter D2 is set larger than the diameter D1 of the first socket opening 25.

  The cover fixing groove 28 is formed at a position outside the first socket opening 25.

  Further, the plug 22 is caulked and fixed by the caulking fixing portion 33 with the peripheral portion held by the holding portion 32, whereby the other end side (the lower end side in FIG. 2) of the inner chamber 24, that is, the second socket. The opening 26 is closed.

  The ball seat 17 is made of, for example, a synthetic resin having excellent wear resistance and a high elastic modulus, and is formed in a cylindrical shape that can be fitted into the inner chamber 24 of the socket body 21. That is, the ball seat 17 includes a spherical sliding surface 35 inside, and the first end of the socket body 21 is connected to the sliding surface 35 at one end (upper end in FIG. 2). A first sheet opening 36 serving as one sheet opening serving as a sheet insertion opening communicating coaxially with the socket opening 25 is provided, and a sliding surface is provided at the other end (lower end in FIG. 2). A second sheet opening 37 that is the other sheet opening is provided as a sheet communication opening that communicates coaxially with the second socket opening 26 of the socket main body 21 continuously to 35. The ball sheet 17 is held between the projecting portion 31 of the socket body 21 and the plug 22. Note that the ball sheet 17 may be formed by a single member, or may be configured by combining a plurality of members formed of, for example, synthetic resins having different characteristics.

  The ball stud 18 is integrally provided with a spherical ball portion 41 and an axial stud portion 42 connected to the ball portion 41.

  The ball portion 41 is made of a metal such as high carbon steel, for example, and a part of the outer peripheral surface including the equator (maximum diameter position) is slidably held on the sliding surface 35 of the ball seat 17 so as to be slidable (rotatable). ing. That is, the ball portion 41 is accommodated in the inner chamber 24 of the socket 16 together with the ball seat 17. Further, the ball portion 41 has an equator outer diameter dimension, that is, a maximum outer diameter dimension D3 which is substantially equal to the maximum inner diameter dimension of the sliding surface 35 of the ball seat 17, and the first socket opening 25 diameter dimension. It is larger than D1 and smaller than the diameter D2 of the second socket opening 26 (D2> D3> D1). Further, although not shown, for example, a lubricant (grease) is held between the outer peripheral surface of the ball portion 41 and the sliding surface 35 of the ball seat 17.

  The stud portion 42 is made of, for example, low carbon steel, that is, a metal made of a material different from that of the ball portion 41, a cylindrical stud portion main body 45, and a disk-like shape protruding from the outer periphery of the stud portion main body 45. And the buttocks 46. The stud portion 42 protrudes outward (upward in FIG. 2) of the socket 16.

  The stud main body 45 includes a columnar main body 47 constituting a distal end side (upper end side in FIG. 2) which is one end side, and a proximal end side (lower end in FIG. 2) which is the other end side of the main body section 47. A holding projection 48 having a diameter larger than that of the main body 47, and a base end portion 49 gradually reduced in diameter from the holding projection 48 to the other end (the lower end in FIG. 2) Is integrated.

  On the outer peripheral surface of the main body portion 47, a screw portion 51 is formed as a fixing portion as a fastening portion that is fastened (screwed) to the attached member.

  The holding protrusion 48 is positioned away from the flange 46 on the other end side (base end 49 side). Therefore, a fixing groove portion 53 for attaching and fixing the end portion of the dust cover 19 is formed in an annular shape on the outer peripheral surface of the stud portion main body 45 between the holding projecting portion 48 and the flange portion 46.

  The base end portion 49 is connected to the center of the ball portion 41, that is, substantially coaxial with the center of the ball 41, for example, by welding by projection welding. Therefore, the axial direction of the stud body 45 (stud portion 42) is along the central axis of the socket body 21 (socket 16) in an unloaded state, and is orthogonal (crossed) to the equator of the ball portion 41 in front view. )is doing.

  In addition, the flange portion 46 is located, for example, near the proximal end side (closer to the proximal end portion 49) of the stud body 45, and when the screw portion 51 is fastened (screwed) to the attached member, the screw portion One main surface 46a (upper surface in FIG. 2) facing the 51 side is a fastening seat surface with the mounted member. The flange portion 46 is formed, for example, coaxially with the stud portion main body 45, and the diameter dimension D4 of the outer peripheral surface 46b is set larger than the diameter dimension D3 of the ball portion 41.

  The dust cover 19 is also called a dust seal or a boot, and is formed in a flat cylindrical shape (a dimension in the radial direction is larger than that in the axial direction) by using, for example, soft rubber or soft synthetic resin. The dust cover 19 is attached and fixed so that one end side (the upper end side in FIG. 2) is pressed against the fixing groove 53 in the central axis direction, and the other end side (the lower end side in FIG. 2) is the cover of the socket 16. It is fixedly attached to the fixing groove 28. Further, a pressure contact portion 55 is formed on one end side (the upper end side in FIG. 2) of the dust cover 19 so as to be pressed against the outer peripheral surface 46b of the flange portion 46. Therefore, the dust cover 19 covers the first socket opening 25 (the first sheet opening 36 of the ball seat 17) of the socket 16 regardless of the swinging of the ball stud 18, and enters the inside of the socket 16 or the ball seat 17. Prevents the intrusion of dust.

  Next, a method for manufacturing the ball joint 11 according to the embodiment will be described.

  First, as shown in FIG. 1 (a), a ball portion 41 formed in a spherical shape in advance from the second socket opening 26 side of the socket body 21 formed by forging or casting in advance is formed inside the socket body 21 ( Insert into the inner chamber 24) (insertion step).

  Next, as shown in FIG. 1 (b), a part of the ball portion 41 (the upper end portion in the figure) inserted into the socket body 21 is moved from the first socket opening 25 to the outside (upward in the figure). Project so that it protrudes. At this time, the socket body 21 and the ball portion 41 are held in a non-contact state by being held by holding members such as a jig (not shown), and one of the ball portions 41 is provided from the first socket opening 25. The state where the part (the upper part in the figure) protrudes to the outside is maintained. Then, as shown in FIG. 1 (c), the base end portion 49 of the stud portion main body 45 of the stud portion 42 in which the flange portion 46 is formed integrally with the ball portion 41 at the protruding position is first with respect to the ball portion 41. For example, projection welding is performed from the socket opening 25 side (welding process). This welding position is on the outer side of the socket body 21 with respect to the first socket opening 25.

  Thereafter, a pre-formed ball sheet 17 is assembled inside the socket body 21 (inner chamber 24) so that the ball portion 41 is slidably held by the sliding surface 35, and the pre-formed plug 22 is held by the holding portion. After being attached to 32, the ball seat 17 holding the ball part 41 is accommodated and held inside the socket 16 together with the ball part 41 by deforming the caulking fixing part 33 of the socket body 21 toward the central axis. The dust cover 19 molded in advance is assembled between the socket 16 (socket body 21) and the ball stud 18 (stud portion 42), thereby completing the ball joint 11 (assembly process).

  As described above, in the above embodiment, the ball portion 41 is inserted into the socket body 21 from the second socket opening 26 of the socket body 21, and the flange portion 46 is inserted into the tip of the ball portion 41. The base end side (the other end side) of the stud portion 42 formed on the side (one end side) is welded from the first socket opening 25 side of the socket body 21.

  For this reason, since the flange portion 46 of the stud portion 42 is not inserted (inserted) into the openings 25 and 26 of the socket body 21, the flange portion 46 regardless of the diameter size of the openings 25 and 26, etc. Can be set freely. That is, the diameter dimension D4 of the flange part 46 can be set larger than the diameter dimension D3 of the ball part 41, for example.

  In addition, since a process of separately assembling the flange portion 46 with respect to the stud portion 42 is not required later, it is not necessary to reduce the manufacturability, and the first socket opening 25 side of the socket body 21 needs to be caulked and deformed. Therefore, the quality can be ensured, for example, the diameter of the first socket opening 25 and the torque of the ball joint 11 can be stabilized.

  In the welding process, a part of the ball portion 41 inserted into the socket body 21 is projected from the first socket opening 25 of the socket body 21 to the outside of the socket body 21, and the socket is located at the projected position. By welding the stud portion 42 to the ball portion 41 from the first socket opening 25 side of the main body 21, even if spatter is generated during welding, this spatter adheres to the inside of the socket main body 21 (inner chamber 24). Therefore, the quality of the socket 16 (socket main body 21) can be ensured, and the process of removing the spatter adhering to the socket main body 21 becomes unnecessary, so that the productivity can be further improved.

  Furthermore, for example, in the case of the ball joint 11 used for the stabilizer link, it is required that the slidability is good. The slidability of the ball joint 11 depends on the surface roughness and sphericity of the ball part 41, and a material having a certain degree of hardness is required when finishing the outer peripheral surface of the ball part 41 with higher accuracy. As the ball portion 41, for example, high carbon steel is suitable. On the other hand, in the case of such a ball joint 11, since the load applied to the stud portion 42 is not so large, it is a low carbon steel that is relatively low in hardness and inexpensive than a high carbon steel that is relatively high in hardness and expensive. It can respond sufficiently. Thus, by forming the ball part 41 and the stud part 42 from different materials, the ball part 41 and the stud part 42 can be made of materials suitable for each, and the characteristics of the ball joint 11 can be improved. At the same time, the cost can be reduced.

  In the above-described embodiment, the ball joint 11 can be used at an arbitrary location such as a vehicle steering device (steering device).

  Further, the ball part 41 and the stud part 42 may be made of the same material as each other, and may be any metal suitable for welding other than carbon steel, for example.

11 Ball joint
16 socket
18 Ball stud
21 Socket body
22 Plug as a blocking member
25 First socket opening as one opening
26 Second socket opening as the other opening
41 Ball
42 Stud section
46 Buttocks

Claims (3)

A cylindrical socket body having one opening at one end and the other opening larger than the one opening at the other end, and a closing member for closing the other opening of the socket body A socket having a spherical ball portion that is rotatably held inside the socket main body of the socket and has a diameter smaller than that of the other opening and larger than that of the one opening. A ball joint manufacturing method comprising: a ball stud having a shaft-like stud portion protruding from the one of the socket main body and projecting to the outside of the socket body;
An insertion step of inserting the ball portion into the socket body from the other opening of the socket body;
A method for manufacturing a ball joint, comprising: a welding step of welding the stud portion from the one opening side of the socket body to the ball portion inserted into the socket body. In the welding process, a part of the ball portion inserted into the socket body is protruded to the outside from one opening portion of the socket body, and the stud portion is moved to the one side of the socket body at the protruding position. The ball joint manufacturing method according to claim 1, wherein welding is performed to the ball portion from the opening side. The method for manufacturing a ball joint according to claim 1 or 2, wherein the ball portion and the stud portion are formed of different materials.

Images