JP2010101424A - Ball joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long-life ball joint comprising a ball stud 18 with low and stable oscillation torque in starting and a resin seat 17 hard to be worn away. <P>SOLUTION: The resin seat 17 is interposed between a housing 16 and a ball head part 23 of the ball joint 12. The resin seat 17 is formed of two pieces, which are a first seat 21 arranged near an inlet of a storage room 19 of the housing 16 and a second seat 22 arranged at the bottom of the storage room 19. A space S is provided between the first seat 21 and the second seat 22. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ball joint.

  In general, a ball joint has a ball head provided at one end of a ball stud and a resin sheet covering the ball head. The bottom of the housing is sealed and the other end is used as an entrance for the resin sheet and the ball head. Contained in a storage room. For example, an inner ball joint or the like of a steering apparatus for an automobile has the resin sheet and a ball head accommodated in a storage chamber through the entrance, and the entrance of the ball is made smaller by diameter by crimping the entrance. The resin sheet is configured to be prevented from coming off and preloaded.

  As the resin sheet, there is used a one-piece formed in a cup shape in which a bottom portion facing the bottom of the storage chamber is provided at one end of a cylindrical peripheral wall portion and the opposite side is opened (see, for example, Patent Document 1). In addition, as the resin sheet, one that is formed in a cup shape by forming the bottom side and the inlet side of the cup in separate two pieces is also used (see, for example, Patent Document 2). In any case, the conventional resin sheet is generally formed so as to cover almost the entire surface of the ball head and to fill almost the entire interior of the accommodation chamber. The storage chamber is filled with grease or the like as a lubricant.

However, when the ball stud of the ball joint incorporating the conventional resin sheet is first swung after assembling, or when the ball stud is swung and stopped for a while and then restarted, that is, when the ball stud is started. In addition to the large dynamic torque, there is a problem that the swinging torque is not stable, for example, when the swinging is repeated, the swinging torque decreases rapidly and greatly. In addition, the conventional ball joint has a problem that when a poor lubrication occurs or a foreign substance is mixed in the storage chamber, the resin sheet is easily worn and loosened in a short period of time, resulting in a short life.
JP-A-7-12116 Japanese Patent Publication No. 6-8645

  In order to cope with the above problems, conventionally, the type of resin that is a resin sheet forming material can be selected, the shape and structure of the resin sheet and the storage chamber can be devised, or the grade of grease can be selected. Has been done. However, no matter what measures are taken, there are limits to the effects of lowering the swing torque at start-up, stabilizing the swing torque, and extending the life of the ball joint by suppressing the wear of the resin sheet. there were.

  An object of the present invention is to provide a ball joint having a long life since the swinging torque at the time of starting is lower and more stable than before and the resin sheet is not easily worn.

  To achieve the above object, the present invention accommodates a ball stud (18) having a ball head (23) at one end, a resin sheet (17) covering the ball head, the resin sheet and the ball head. A housing (16) having a small diameter by caulking after accommodating a spherical head covered with a resin sheet. The resin sheet is formed in an annular shape surrounding the entrance of the storage chamber, and is disposed near the entrance, and receives a force when a force in the direction of pulling the ball head out of the entrance is applied to the ball stud ( 21), and is formed in a bowl shape that receives the tip of the ball head, and is disposed at the bottom of the receiving chamber, and receives a force when the force in the direction of pressing the ball head against the bottom acts on the ball stud. Formed in two pieces of two sheets (22), There is provided a ball joint (12), characterized in that the space (S) is provided in the serial first sheet and between the second sheet (claim 1). The alphanumeric characters in parentheses represent corresponding components in the embodiments described later.

  The inventor has examined that the conventional resin sheet substantially functions to support the ball head with respect to the housing when the ball stud swings or when a load is applied to the ball stud. It is a region (hereinafter referred to as “first pressure receiving region”) that receives the force when the force in the direction of pulling out the ball head from the inlet acts on the ball stud in the vicinity of the inlet side of the storage chamber. , Only a region near the bottom of the housing chamber that receives the force when the force in the direction of pressing the ball head against the bottom acts on the ball stud (hereinafter referred to as “second pressure receiving region”), and resin It became clear that the area between the two areas of the sheet (hereinafter referred to as “intermediate area”) does not have the above function.

  Not only that, the presence of the intermediate region increases the contact area between the resin sheet and the ball head, which causes an increase in swing torque especially at the start-up, The gap between the head and the ball is filled almost entirely, and there is no escape space for foreign matter that has entered the storage chamber or wear powder generated by wear of the resin sheet itself. It has also been clarified that the existence between the sheet and the ball head is the main cause of promoting the wear of the resin sheet.

  On the other hand, according to the present invention, the first sheet corresponding to the first pressure receiving region near the inlet side of the storage chamber, which actually functions to support the ball head with respect to the housing, the resin sheet, By forming the two-sheet two-piece corresponding to the second pressure receiving area near the bottom of the storage chamber, the intermediate area between the two areas is omitted, and the contact area between the resin sheet and the ball head is increased. Can be made smaller.

In addition, by forming the resin sheet in the two-piece of the first and second sheets, the space provided between the two sheets functions as a grease reservoir, and in order to maintain good lubrication from the space to both sheets The necessary and sufficient amount of grease can be continuously supplied.
Further, the space functions as a refuge for foreign matter that has entered the storage chamber or wear powder generated by wear of the resin sheet itself, and the foreign matter or wear powder continues to exist between the resin sheet and the ball head. Can also be suppressed.

Therefore, according to the present invention, since the swing torque at the time of starting is lower and more stable than in the prior art, and the resin sheet is not easily worn, a long-life ball joint can be provided.
According to the present invention, the vicinity of the entrance of the storage chamber is caulked so that the gap with the ball head is narrow on the entrance side and increases toward the bottom of the storage chamber, and the first sheet corresponds to the clearance. It can be formed so that it is thin on the inlet side of the storage chamber and thicker toward the bottom of the storage chamber.

In this case, when the ball stud is swung, based on the thickness difference, the first sheet is prevented from being displaced along with the swing, and the ball head is moved by the first sheet. , It can continue to be supported stably with respect to the housing.
According to the invention, the bottom of the second sheet corresponding to the bottom of the storage chamber is provided with a convex portion (58) protruding toward the bottom, and the convex portion is fitted to the bottom of the storage chamber. A recessed part (50) can be provided and the said recessed part and a convex part can be mutually fitted together (Claim 3).

  In this case, when the ball stud is swung, the fitting prevents the second seat from being displaced along with the swing, and the ball head is moved to the housing by the second seat. On the other hand, it can continue to be supported stably.

Embodiments of the present invention will be specifically described below with reference to the drawings.
FIG. 1 is a schematic diagram illustrating a schematic configuration of a steering apparatus 1 including a ball joint according to an embodiment of the present invention. The steering device 1 includes a steering wheel 2 as a steering member and a rack and pinion mechanism 3 as a turning mechanism for turning steered wheels (not shown).

The steering wheel 2 is connected to the rack and pinion mechanism 3 via a steering shaft 4 and an intermediate shaft 5. The rotation of the steering wheel 2 is transmitted to the rack and pinion mechanism 3 via the steering shaft 4 and the intermediate shaft 5.
The rack and pinion mechanism 3 includes a pinion shaft 6 and a rack shaft 7. The pinion shaft 6 includes a shaft portion 8 connected to the intermediate shaft 5 and a pinion 9 connected to the tip of the shaft portion 8. The rotation of the steering wheel 2 is transmitted to the pinion shaft 6 via the steering shaft 4 and the intermediate shaft 5.

The rack shaft 7 extends along the left-right direction of the vehicle. A rack 10 is formed on the rack shaft 7. The pinion 9 and the rack 10 are meshed with each other. The rotation of the pinion shaft 6 is converted into an axial movement of the rack shaft 7 by the rack 10 and the pinion 9.
The rack shaft 7 is inserted into a cylindrical housing 11. Both end portions of the rack shaft 7 protrude from the housing 11. One end of a tie rod 14 is connected to each end of the rack shaft 7 via an inner ball joint 12. An outer ball joint 13 is provided at the other end of the tie rod 14 (so-called tie rod end). Although not shown, the steered wheels are connected to the outer ball joint 13 via a knuckle arm.

  A cylindrical rack boot 15 is disposed at each end of the housing 11. One end of each rack boot 15 is fitted around the end of the housing 11 and is fixed to the end. Further, the other end of each rack boot 15 is externally fitted to the tie rod 14 and is fixed to the tie rod 14. The end of the housing 11 and the inner ball joint 12 are covered with a corresponding rack boot 15. The rack boot 15 prevents foreign matters such as water and dust from entering the housing 11 and the inner ball joint 12.

  In the steering operation (rotation operation), as described above, the rotation of the steering wheel 2 is transmitted to the pinion shaft 6 by the steering shaft 4 and the intermediate shaft 5, and the rotation of the pinion 9 is moved in the axial direction of the rack shaft 7 through the rack 10. Converted. The axial movement of the rack shaft 7 at that time is transmitted to the tie rod 14 via the inner ball joint 12, and the movement of the tie rod 14 is further transmitted to the knuckle arm via the outer ball joint 13.

FIG. 2 is a cross-sectional view of a part of the steering device 1 including the inner ball joint 12 and the outer ball joint 13.
The inner ball joint 12 includes a housing 16 connected to the end of the rack shaft 7, and a resin sheet 17 and a ball stud 18 held by the housing 16. The housing 16 includes a storage chamber 19 that stores the resin sheet 17 and the ball stud 18, and a connecting portion 20 that is connected to the end of the rack shaft 7. The storage chamber 19 has a cylindrical shape with a sealed bottom and has an inlet. In addition, the resin sheet 17 is formed in a two-piece configuration including a first sheet 21 disposed near the entrance of the storage chamber 19 and a second sheet 22 disposed at the bottom of the storage chamber. A space S is provided between the first sheet 21 and the second sheet 22.

  The ball stud 18 is integrally provided with a spherical head 23 having a spherical outer surface and a rod 24 extending so as to protrude from the spherical head 23. The spherical head 23 is covered with the resin sheet 17, and the rod 24 protrudes from the storage chamber 19. A part of the tie rod 14 is constituted by a ball stud 18. That is, the tie rod 14 includes a ball stud 18 and a connecting shaft 25 connected to the rod 24 of the ball stud 18.

The entrance of the storage chamber 19 is caulked after receiving the ball head 23 covered with the resin sheet 17 to have a small diameter so that the ball head 23 and the resin sheet 17 are prevented from coming off.
A male screw portion 26 is formed at the tip portion (right end portion in FIG. 2) of the rod 24. The male screw portion 26 is screwed into a female screw hole 27 formed in the connecting shaft 25. The male screw portion 26 is screwed into the female screw hole 27, whereby the connecting shaft 25 is coaxially connected to the ball stud 18.

  A lock nut 28 is screwed into the male screw portion 26. The ball stud 18 and the connecting shaft 25 are fixed to each other by a lock nut 28. Further, the screwing amount of the male screw portion 26 with respect to the female screw hole 27 is adjusted by a lock nut 28. The toe angle of the steered wheel can be adjusted by adjusting the screwing amount of the male screw portion 26 into the female screw hole 27.

  The ball head 23 is held so as to be wrapped in the storage chamber 19 via the resin sheet 17. The inner peripheral surface of the resin sheet 17 has a shape along the outer surface of the ball head 23. The ball head 23 is slidable with respect to the resin sheet 17. A lubricant such as grease is filled between the resin sheet 17 and the ball head 23. The ball stud 18 can swing with respect to the housing 16 with the ball head 23 as a fulcrum. Therefore, the movement of the rack shaft 7 (see FIG. 1) in the axial direction is not transmitted linearly to the tie rod 14 in the axial direction, but is transmitted in the angular direction where the inner ball joint 12 swings.

  On the other hand, the outer ball joint 13 includes a housing 29 and a resin sheet 30 and a ball stud 31 held by the housing 29. The housing 29 includes a cylindrical member 32 in which the resin sheet 30 is disposed, and a closing plate 33 fixed to the one end so as to close one end (the lower end in FIG. 2) of the cylindrical member 32. The cylindrical member 32 is integrally formed at the distal end portion of the connecting shaft 25, for example.

  The resin sheet 30 includes a cup-shaped first sheet 34 and a plate-shaped second sheet 35. The first sheet 34 is integrally provided with a peripheral wall portion 36 and a bottom portion 37. The first sheet 34 is disposed such that the peripheral wall portion 36 is along the inner peripheral surface of the cylindrical member 32. The second sheet 35 is interposed between the bottom 37 of the first sheet 34 and the closing plate 33. The resin sheet 30 is held between an annular flange 38 projecting inward from the other end (upper end in FIG. 2) of the cylindrical member 32 and the closing plate 33.

  The ball stud 31 is integrally provided with a spherical head 39 having a spherical outer surface and a rod 40 protruding upward from the spherical head 39. The spherical head 39 is covered with the first sheet 34, and the rod 40 protrudes from the cylindrical member 32. The spherical head 39 is held by the housing 29 via the first sheet 34. That is, the ball stud 31 is held by the housing 29 via the first sheet 34.

  The inner peripheral surface of the first sheet 34 is shaped along the outer surface of the ball head 39. The spherical head 39 is slidable with respect to the resin sheet 30. A lubricant such as grease is filled between the first sheet 34 and the ball head 39. The ball stud 31 can swing with respect to the housing 29 with the ball head 39 as a fulcrum. Further, the ball stud 31 is rotatable around the central axis of the rod 40. The outer ball joint 13 transmits the movement of the tie rod 14 to the knuckle arm in the swinging angular direction.

  A cylindrical cover 41 is attached to the housing 29 and the ball stud 31. One end of the cover 41 is fitted around the end of the cylindrical member 32 and is fixed to the end. The other end of the cover 41 is externally fitted to the rod 40 and is fixed to the rod 40. An end of the cylindrical member 32 and a part of the rod 40 are covered with a cover 41. The cover 41 prevents foreign matters such as water and dust from entering the outer ball joint 13.

Next, a specific configuration of the ball joint according to this embodiment will be described by taking the inner ball joint 12 as an example.
FIG. 3 is a partial cross-sectional view showing a schematic configuration of the inner ball joint 12 according to the embodiment of the present invention. FIG. 4 is a partial cross-sectional view showing a state in which the inner ball joint 12 is being assembled.

With reference to FIG. 3, the inner ball joint 12 includes a ball stud 18, a housing 16, and a resin sheet 17. The ball stud 18 is an integrally molded product using a single member made of metal such as steel, and includes a ball head 23 and a rod 24. The center C of the spherical head 23 is disposed on the central axis L1 of the rod 24.
The housing 16 accommodates the ball head 23 and supports the ball stud 18 via the resin sheet 17 so as to be swingable with the ball head 23 as a fulcrum. The housing 16 is an integrally molded product using a single member made of metal such as steel, and includes a storage chamber 19 and a connecting portion 20 (see FIG. 2). The storage chamber 19 includes a cylindrical peripheral wall 42 that surrounds the spherical head 23, and a bottom wall 43 that is connected to one end of the peripheral wall 42 in the axial direction and seals one end of the cylinder to form a cylinder.

  Referring to FIGS. 3 and 4, the bottom of storage chamber 19 has one side surface (inner bottom surface) 45 of bottom wall 43 and concave surface 46 that surrounds inner bottom surface 45 and is continuous with inner peripheral surface 44 of peripheral wall 42. Contains. The inner bottom surface 45 is formed to be recessed from the concave surface 46 through the step 47 in the direction opposite to the opening (downward in both drawings), whereby the concave portion 50 is provided at the bottom of the storage chamber 19. The shape of the recess 50 in the direction of the plane A perpendicular to the central axis L2 of the storage chamber 19 is formed in a circular shape having a constant inner diameter from the opening on the concave surface 46 side to the inner bottom surface 45 with the central axis L2 as the center.

  The inner peripheral surface 44, the concave surface 46, and the concave portion 50 (step 47 and inner bottom surface 45) are successively connected, and the inner space 44, the concave surface 46, and the concave portion 50 accommodate the spherical head 23 and the resin sheet 17. 51 is divided. The inner peripheral surface 44 and the concave surface 46 are opposed to the surface of the spherical head 23. A connecting portion 20 (see FIG. 2) is integrally formed on the bottom wall 43.

  With reference to FIG. 3, an opening 48 is formed at the other end (tip) of the peripheral wall 42, and the spherical head 23 is accommodated in the accommodation space 51 through the opening 48. The rod 24 is inserted through the opening 48. The peripheral portion 49 of the opening 48 of the peripheral wall 42 has a smaller diameter than the other portions of the peripheral wall 42, and the ball head 23 and the resin sheet 17 are prevented from coming out of the storage chamber 19. 3 and 4, this peripheral portion 49 has a small diameter by caulking (plastically deforming) the other end (tip) of the peripheral wall 42 on the side of the opening 48 of the peripheral wall 42 having a substantially constant outer diameter. It is said that.

With reference to FIG. 3, the resin sheet 17 is formed in a two-piece form of a first sheet 21 and a second sheet 22, and a space S is provided between the first sheet 21 and the second sheet 22. Thereby, the intermediate area between the 1st sheet | seat 21 and the 2nd sheet | seat 22 is abbreviate | omitted, and the contact area of the resin sheet 17 and the ball | bowl head 23 can be made smaller than before.
In addition, by forming the two sheets of the first sheet 21 and the second sheet 22, the space S provided between the sheets 21 and 22 functions as a grease reservoir, and the space S is improved from the space S to the sheets 21 and 22. An amount of grease necessary and sufficient to maintain proper lubrication can be continuously supplied.

Further, the space S functions as a refuge for foreign matter that has entered the storage chamber 19 and wear powder generated by wear of the resin sheet 17 itself, so that the foreign matter and wear powder are placed between the resin sheet 17 and the ball head 23. It can also be suppressed to continue to exist in between.
For this reason, the swing torque at the time of activation is lower and more stable than in the prior art, and the resin sheet 17 is less likely to be worn, so that a long-life ball joint 12 can be provided.

  The first sheet 21 is formed in an annular shape surrounding the entrance of the storage chamber 19 and is disposed near the entrance. Specifically, the first sheet 21 has a spherical head 23 in a state where the center axis L1 of the rod 24, the center axis L2 of the storage chamber 19 and the center axis L3 of the resin sheet 17 coincide (state of FIG. 3). Is disposed at a position corresponding to the first pressure receiving region 52 located closer to the opening 48 of the storage chamber 19 than the plane A orthogonal to the central axis L1 to L3.

When the force F1 is applied to the first pressure receiving region 52 in the direction in which the ball head 23 is pulled out from the opening 48 via the rod 24 (for example, one U1 in the direction along the central axes L1 to L3 in FIG. 3), This is the region that receives the force F1. The first sheet 21 is integrally formed of resin.
Referring to FIG. 4, the first sheet 21 is formed in a ring shape. With reference to FIGS. 3 and 4, the other end (front end) of the peripheral wall 42 on the opening 48 side in a state where the first sheet 21, the second sheet 22, and the ball head 23 are accommodated in the accommodating space 51 of the accommodating chamber 19. ), The ring-shaped first sheet 21 is elastically deformed so as to fill the gap between the storage chamber 19 and the ball head 23, and the first sheet 21 and the second sheet 22 are preloaded.

  FIG. 5 is an enlarged cross-sectional view of the first seat 21 portion of the inner ball joint 12 of FIG. With reference to FIG. 3 and FIG. 5, the deformed inner peripheral surface 53 of the first sheet 21 is formed in a shape along the surface of the ball head 23 and slidably supports the ball head 23. The outer peripheral surface 54 of the first sheet 21 is formed in a shape along the inner peripheral surface 44 of the storage chamber 19 and supported by the inner peripheral surface 44.

  In addition, the vicinity of the entrance of the storage chamber 19 is caulked so that the gap with the ball head 23 is narrow on the entrance side and increases toward the bottom of the storage chamber 19, that is, downward in both figures. The one sheet 21 is deformed corresponding to the gap by the caulking, and the thickness T1 on the inlet side of the storage chamber 19 is thinner than the thickness T2 on the bottom side of the storage chamber, and the thickness therebetween is toward the bottom of the storage chamber 19. It is formed to be thick.

  Thus, when the ball stud 18 is swung, the first sheet 21 is prevented from being displaced due to the rocking based on the thickness difference, and the central axis L3 of the first sheet 21 is prevented. Can be stably supported by the first sheet 21 with respect to the housing 16 while maintaining a state (the state of FIG. 3) that coincides with the central axis L <b> 2 of the storage chamber 19.

The second sheet 22 is formed in a bowl shape that receives the tip of the ball head 23, and is disposed at the bottom of the storage chamber 19. Specifically, the second sheet 22 corresponds to the second pressure receiving region 55 located on the side farther from the opening 48 of the storage chamber 19 than the plane A in the state of FIG. 3 in which the central axes L1 to L3 coincide. It is arranged at the position to do.
When the force F2 is applied to the second pressure receiving region 55 in the direction in which the ball head 23 is pressed against the bottom of the storage chamber 19 via the rod 24 (for example, the other U2 in the direction along the central axes L1 to L3 in FIG. 3). This is the region that receives this force F2. The second sheet 22 is integrally formed of the same or different resin that forms the first sheet 21.

The 2nd sheet | seat 22 is formed in the shape where the internal peripheral surface 56 follows the front-end | tip of the spherical head 23, and supports the spherical head 23 so that sliding is possible. The outer peripheral surface 57 of the second sheet 22 is formed in a shape along the concave surface 46 of the storage chamber 19 and is supported by the concave surface 46. The shape of the second sheet 22 in the plane A direction orthogonal to the central axis L3 is formed in a circle centered on the central axis L3.
A convex portion 58 that protrudes toward the inner bottom surface 45 is provided on a bottom portion of the outer peripheral surface 57 of the second sheet 22 that corresponds to the inner bottom surface 45 of the storage chamber 19. The convex portion 58 is formed in a circular shape having a constant outer diameter from the base end on the outer peripheral surface 57 side to the front end facing the inner bottom surface 45 of the storage chamber 19 with the central axis L3 as the center. Yes. The outer diameter of the convex portion 58 matches the inner diameter of the concave portion 50 of the storage chamber 19.

  The second sheet 22 is disposed on the bottom of the storage chamber 19 with the convex portion 58 fitted into the concave portion 50 of the storage chamber 19 and the outer peripheral surface 57 along the concave surface 46. Thus, when the ball stud 18 is swung, the fitting prevents the second sheet 22 from being displaced due to the swinging, so that the center axis L3 of the second sheet 22 is accommodated in the housing chamber. The ball head 23 can be stably supported with respect to the housing 16 by the second sheet 22 while maintaining the state (the state of FIG. 3) that matches the center axis L <b> 2 of 19.

In the fitted state, a gap 59 is provided between the inner bottom surface 45 of the concave portion 50 and the tip of the convex portion 58 opposed thereto. In addition, the convex portion 58 is provided with a through hole 60 that reaches from the inner peripheral surface 56 to the tip that faces the inner bottom surface 45 of the concave portion 50. The shape of the through hole 60 in the plane A direction is formed in a circular shape with the central axis L3 as the center and a constant inner diameter.
By providing the gap 59 and the through hole 60, the rigidity of the second sheet 22 can be reduced and elastic deformation can be easily performed. Further, the gap 59 and the through hole 60 function as a grease reservoir together with the space S, and a sufficient amount of grease necessary and sufficient for maintaining good lubrication from the gap 59 and the through hole 60 to the both sheets 21 and 22. Can be continuously supplied.

  Therefore, the space S is provided between the first sheet 21 and the second sheet 22, the first sheet 21 is formed in an annular shape that surrounds the entrance of the storage chamber 19 and corresponds only to the first pressure receiving region 52, When the two sheets 22 are arranged at the bottom of the storage chamber 19 and formed in a bowl shape corresponding only to the second pressure receiving region 55, the other end on the opening 48 side of the storage chamber 19 is crimped to have a small diameter. Variation in processing can be satisfactorily absorbed by the elastic deformation of both sheets 21 and 22 and the increase or decrease of the space S accompanying the movement of the first sheet 21. Therefore, variation in preload applied to the first seat 21 and the second seat 22 can be reduced, and the swing torque of the ball stud 18 can be further stabilized.

Further, the gap 59 and the through hole 60 are caused to function as a refuge for foreign matter that has entered the storage chamber 19 and wear powder generated by wear of the resin sheet 17 itself, so that the foreign matter and wear powder are in contact with the resin sheet 17 and the ball head. It is also possible to suppress the presence between the portions 23.
The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the claims. Further, the ball joint of the present invention can be used for applications other than the application for connecting the rack shaft and the tie rod.

It is a mimetic diagram showing a schematic structure of a steering device provided with a ball joint concerning one embodiment of the present invention. It is a sectional view of a part of a steering device including an inner ball joint and an outer ball joint. It is a partial sectional view showing a schematic structure of an inner ball joint concerning one embodiment of the present invention. It is a partial sectional view showing a state during the assembly of the inner ball joint. It is sectional drawing to which the part of the 1st sheet | seat was expanded among the inner ball joints of FIG.

Explanation of symbols

  12: Ball joint (inner ball joint), 16: Housing, 17: Resin sheet, 18: Ball stud, 19: Storage chamber, 21: First seat, 22: Second seat, 23: Ball head, S: Space .

Claims (3)

A ball stud having a ball head at one end;
A resin sheet covering the ball head;
A housing chamber for housing the resin sheet and the ball head, the bottom of the housing chamber is sealed, and the inlet is a caulked housing having a small diameter after housing the ball head covered with the resin sheet. Prepared,
The resin sheet is
A first seat that is formed in an annular shape surrounding the entrance of the housing chamber, is disposed close to the entrance, and receives a force when a force in a direction of pulling the ball head out of the entrance is applied to the ball stud; It is formed in a bowl shape that receives the tip of the second sheet, and is arranged on the bottom of the storage chamber, and is formed in a two-piece two-piece seat that receives the force when acting on the ball stud in the direction of pressing the ball head against the bottom. A ball joint, wherein a space is provided between the first sheet and the second sheet.   The vicinity of the entrance of the storage chamber is caulked so that the gap with the ball head is narrow on the entrance side and increases toward the bottom of the storage chamber, and the first sheet corresponds to the clearance. The ball joint according to claim 1, wherein the ball joint is formed so as to be thin on the inlet side and thick toward the bottom of the storage chamber.   A convex portion projecting toward the bottom is provided on the bottom portion of the second sheet corresponding to the bottom of the storage chamber, and a concave portion is provided on the bottom of the storage chamber to which the convex portion is fitted. The ball joint according to claim 1 or 2, wherein the convex portions are fitted together.

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