MXPA96002233A - Composite encased ball joint - Google Patents

Abstract

A motor vehicle ball joint assembly includes a ball stud having a ball stud axis with a shank portion and a ball end centered thereon. A bearing liner has an open end disposed over the ball end with the open directed toward the shank portion. The bearing liner has a bearing surface engaging the ball end. A plurality of slits extend from the open end of the liner, defining a plurality of flex members. The flex members operably deflect to receive the ball end. When the ball end is complety inserted in the liner, the flex members return to a locked position, axially retaining the ball end in the liner. A stem engaging element has a stem axis and extends radially from the bearing liner. The stem engaging element has metal engaging threads. A rigid plastic case envelopes the bearing liner. The rigid plastic case and bearing liner and the rigid plastic case cooperatively positively lock the ball end within the bearing liner. The rigid plastic case fixes the flex fingers in the locked positi on, thereby preventing axial displacement of the ball stud from the liner.

Description

ARTICULATION A ROTULA CONTAINED IN A COMPOSITE MATERIAL FIELD OF THE INVENTION The present invention is related to improvements in the bearings that have plastic bearing shells and plastic outer shells.

BACKGROUND OF THE INVENTION The ball joints normally use a ball bolt and an adapter dowel and are very commonly used in mechanical joints where a first member that is a pivot is associated with a second member and this is also widely used in all joints found in vehicle suspensions automotive. A ball bolt is fixed to one of the members and an adapter sleeve is fixed at the other end and is the second member, with an adapter "which is pivoting on the ball bolt. The ball joints used in the suspension of motor vehicles are designed to hold very large loads and also typically have a ball-and-socket adapter bushing that is formed substantially of steel. The steel adapter sleeves may have a plastic bearing shell. The steel adapter sleeve is bent or crimped around the ball rod to retain it, and the bearing shell is formed or constructed by injecting plastic between the adapter sleeve and the ball bolt. A spherical hinge assembly formed primarily of plastic, the adapter sleeve being reinforced by a cup-shaped cover that retains this member through which a rivet or pin is placed through the ball bolt. One of the advantages of a ball-and-socket joint of an adapter bush is that it is formed primarily of plastic and that it is highly resistant to corrosion and maintains its appearance as new even after many years of being in use. Because the lining is molded around the adapter sleeve and the ball end, the thickness of the liner in any of the places where it is observed depends on the relative position of the ball end and adapter sleeve during molding of the lining . Small variations in the thickness of the lining have a very significant effect on the average life of the patella. If the lining reaches contact between metal and metal the ball bolt can be damaged. The thickness of the bearing shell, and furthermore the durability and therefore the durability of the ball joint assembly, largely depend on the relative position of the ball end and the adapter casing.

It is desired to provide a ball joint with, an adapter sleeve formed substantially of plastic strong enough to be employed in connection applications of automotive vehicle suspensions and to eliminate in some way the variabilities concerning or associated with the use of the metal retention member.

BRIEF DESCRIPTION OF THE INVENTION The ball joints of motor vehicles include a ball bolt "having a ball bolt shaft with a body portion that functions as a ball end which is centered therein. The inserted bearing shell has an open part disposed on the ball end with the open part facing the body portion. The inserted bearing shell has a bearing surface that engages the ball end. A plurality of slits extends from the open terminal to the insert liner area defining a plurality of flexible members. The flexible members are moved apart operationally to receive the ball end. When the ball end is fully inserted into the insert liner, the flexible members returning to the closed position axially retain the ball end in the insert liner area. An element that functions as a gear rod or rod has a rod axis and extends radially from the bearing liner line. The gear rod element has a metal connection structure. A rigid plastic wrap is what makes up the bearing shell. The rigid plastic box and the bearing shell close cooperatively and positively the ball end inside the insert bearing shell. The rigid plastic box fixes the flexible fingers in the closed position, causing or preventing in this way the axial displacement of the ball bolt with the insert liner is prevented. The plastic liner and the plastic box cooperatively provide, jointly with the ball bolt, a high strength, lightweight ball joint assembly structure to increase the superior quality with the bearing liner and of a predetermined thickness. The advantages of the present invention can be better understood with the following specifications and drawings, of which the following is a brief description.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an enlarged view of the components of the first embodiment of a ball joint that is incorporated in the invention. Figure 2 is a side sectional view of the upper plane of the first embodiment. Figure 3 is a sectional view of the first embodiment taken in the direction of the arrows 3 of Figure 2. Figure 4 is an enlarged view of the constituents that make up a second embodiment of a ball joint that is incorporated in the invention. Figure 5 is a side sectional view of an upper plane of the second embodiment. Figure 6 is a sectional view of the second embodiment in the direction of the arrows 6 of Figure 5. Figure 7 is a plan view of a component of the second embodiment in a partially formed condition. Figure 8 is a sectional view of the component of Figure 7 taken in the direction of the arrows 8. Figure 9 is an enlarged view of the components constituting a third embodiment of the invention.

Figure 10 is a top sectional side view of the third embodiment. Figure 11 is a plan view of a component of the third embodiment. Figure 12 is a side elevational view with a partial section of a second embodiment of the component of Figure 8. Figure 13 is an end elevational view of the component of Figure 12.

DESCRIPTION OF A PREFERRED MODALITY A first embodiment of a ball joint 10 is shown in Figure 1-3. The components constituting the ball assembly 10 are mounted so as to reinforce the assembly 12, a spherical insert of the bearing shell 14, and a ball bolt 16. A plastic box 18 is molded on the components that constitute them. Collectively, the reinforced assembly 12, a spherical bearing shell 14 and a molded plastic case 18 constitute the adapter sleeve assembly 19. Ball bolt 16 has a hexagonal projection 20 disposed between a bolt treated in body portion 21 and ball end 22. A longitudinal axis of the ball bolt 23 passes through the ball bolt 16. The configuration of the ball pin 16 is merely exemplary. A graduated body or otherwise could replace the hexagonal projection 20. The reinforced assembly 12 has a forged ring brace 24 with an annular portion 25 having an opening 26 of a predetermined inside diameter. A rod 27 extends from the reinforced ring 24 and is welded by resistance to the projection 28 of the reinforcing ring 24. The reinforcing ring 24 has a transition portion 29 between the annular portion 25 and the projection 28. The rod 27 is a hollow rod with internal and external threads, 30, 31, respectively. A shaft 32 of the rod 27 intersects the axis of the ball bolt 23. Employing the threaded rod for the rod 27 by welding it to the reinforcing ring 24 is a cost effective way to provide the threads. However, other approaches to providing the threads may be employed, as dictated by the needs of the system. For example, the rod 27 could be integrally forged with the reinforcing and threading ring 24 in a separate operation for a stronger ring-to-ring interface. The spherical bearing insert liner 14 has twelve projection outwardly projecting shoulders 34, oriented in a plane parallel to a lower part of the insert liner 14. The shoulders 34 are configured to engage with the opening 26 and therefore the radially positioned insert liner 14 therein. A post 35 located in position, projects from an upper part of the insert liner 14. The post 35 engages with a surface of the mold to place the insert liner 14 during molding. Four expansion slots 36, equally spaced, extend upwards, separating from an open end 37 in the lower part of the insert liner 14 and define four bending fingers 38. The shoulders 34 are placed on the flexing fingers 38. As seen in Figure 2, the plastic box 18 surrounds not only the insert bearing shell 14, but also the reinforcement 12. Only the internal threads 30 of the rod 27 are left exposed. The plastic box 18 includes a skewed cut 39 used for the attachment of a sleeve seal (not shown). The plastic case 18 does not corrode, providing a spherical joint adapter sleeve, which maintains the appearance of a freshly painted display room, without the need for paint to inhibit corrosion or other secondary coating. The assembly 10 of the spherical joint is assembled in the following manner. The spherical bearing insert liner 14 has its open end 37 positioned against the ball end 22 and pressed towards the body portion 21. The flexible fingers 38 are deflected radially outwardly to expand over the ball end 22, allowing the insert liner 14 to press fit onto the ball end 22. The flexible fingers 38 return to a position without locking, providing a bearing surface 40 which engages with the ball end 22. The positioning post 35 is aligned with the axis 23 of the ball bolt with the plane for the shoulders 34 which is consequently normal to the axis 23. The ball pin 16 and the insert liner 14 have their common axis 23 aligned with a center line of the opening 26 and are positioned axially in relation to the reinforcement 12, such that the shoulders 34 engage radially with the opening 26. The opening 26 can be characterized as a receiving surface. With that coupling, the axle 32 of the rod intersects the axis 23 of the ball rod. The ball rod 16, the insert liner 14 and the reinforcement 12 are placed in a mold for the plastic box 18 in the position described above. The positioning post 35, helps to place the insert liner 14 in the mold. The plastic forced into the mold covers the insert liner 14 and the reinforcement 12, flowing around and between the bending fingers 38, the bending fingers 38 are fixed in the locked position. After curing, the plastic coupling locators 34 and position locating post 35 prevent any rotation of the liner 14 of the insert within the plastic case 18. It is preferable that the plastic used for the insert liner 14 have a higher melting point than the plastic used for the box 18, such that the liner of the insert does not melt and allow the ball pin 16 or the reinforcement 12 they move during molding, whereby the thickness of the bearing insert liner is reduced. The reinforcing ring 24 can have either a smooth side, as shown or it can be stepped to increase the area of attachment of the ring with the plastic forming the plastic box 18. Figures 4-6 describe a second embodiment of the inventive spherical hinge assembly 41. The reinforcement 42 of the second embodiment 41 provides the main distinction in the first embodiment 10. As in the first embodiment, the spherical hinge assembly 41 has a spherically formed bearing insert sheath 44, placed on a ball bolt 45, with the ball bolt 45 and the insert liner 44 positioned within the reinforcement 42. The reinforcement 42, the bearing insert liner 44 and the plastic case 46 together constitute the assembly 47 of adapter sleeve or sleeve. The reinforcement 42 has a shallow container 48 providing a receiving surface 49 which engages the outer surface of the insert liner 44. The receiving surface 49 has a predetermined internal diameter. Cutouts 50 are provided on the exterior of the container 48. The container 48 also has a depression 52 of a predetermined depth on its top surface. A rod 54 is connected to the shallow container 48 by a transition portion 56 extending from the container 48. The rod 54 has both the internal threads 58 and the external threads 60., allowing it to be used either as a male or female connector. The 54 has a seam 61 along a lower edge characteristic of the shape in which it was formed. The insert liner 44 has lugs 62 locators and expansion grooves 64 that serve the same roles as the lugs 34 and slots 36 of the first embodiment of the hinge assembly 10. The surface 49 receives in engagement with the shoulders 62. The ball bolt 45 has a ball end 66 and a tapered body 68, but could alternatively be of the configuration of the ball 16. The plastic box 46 surrounds the insert liner 44 and the shallow container 48 and extends through a central void space of the 54, leaving the external threads 60 exposed to serve as a male connector and reinforcing the 54. internal threads 58 help retain the plastic in the shank 54. The box 46 has a slanted cut 70 for the attachment of a sheath seal (not shown). The reinforcement 42 is formed by stamping. A partially formed reinforcement 42 is shown in Figure 7. The internal threads 58 and the external threads 60 are stamped or laminated on the opposite sides of a flat wing plate 72 shown in Figures 7 and 8. The wing plate 72 is wound around a mandrel 74 to form the 54 with the ends of the wing plate 72 meeting to form the seam 61 as shown in Figure 6. The depression 52 is optionally formed in the shallow vessel 48, before the molding plastic box 46 provides a desired positioning of the ball bolt 45 and the bearing insert liner 44 within the container 47. During the molding process, the bearing insert liner 44 engages the closed end of the container 48 to the liner 44 in axial position and the ball bolt 45 therein. The depression 52 can be formed alternatively or increased in depth, after molding the plastic case 46, by pressing a ball tip tool 53 against the top of the plastic case 46 along the axis of the ball bolt. The container 48 and the insert liner 44 flex inwardly resulting in reducing a space between a flat surface 75 on the tip of the ball end 66, thereby increasing the pivoting strength of the ball bolt 45 within the assembly 47 of adapter or sleeve hose. When the ball tip tool is pressed against the plastic case 46, the ball bolt 45 is supported to prevent its movement. Figures 9-11 show a third embodiment 76 of a spherical hinge assembly. A significant distinction between the third embodiment 76 and the first two modes 10 and 40 is the elimination of the reinforcement 12, 42. The ball bolt 16 is shown in this embodiment, although the ball bolt 45 would also serve equally well. An adapter sleeve or sleeve assembly 77 of the third embodiment 76 is positioned on the ball end 22 and includes a one-piece bearing insert 78 with a flange 80, a threaded 82 and a plastic box 84. The third embodiment 76 is intended for applications in light duty vehicles, such as golf carts. The lack of a metal reinforcement completely eliminates the opportunity for corrosion to develop in the assembly 77 of the adapter sleeve or bushing. The bearing insert 78 has a hub portion 86 with four expansion slots 87 therein. Twelve spokes 88 radiate from the cube portion 86 to connect with the flange 80. The flange 80 has eleven ridges 90 similar to teeth and an extension portion 92, each aligned with a spoke 88. The extension portion 92 is connected to flange 80 to a projection portion 94 having a pilot 95 at one end thereof. The 82 has external flanges 96 and internal threads 97. The is positioned on the pilot 95 and centers on itself with a resultant stem shaft 98 that intersects the ball bolt shaft 23. A locator post 91 of the position is placed on top of the portion 86 of the hub. The plastic box 84 surrounds the bearing insert 78 and the 82, engaging the flanges 96 and the wheel 80 and the spokes 88. The plastic box 84 is formed by first pressurizing the bearing insert 78 over the ball end 22 and positioning the rod 82 on the pilot rod 95. The parts 78 , 82, 16 are contained by a upper mold 99 and a lower mold 100. The lower mold 100 can be a split design for capturing the ball bolt and forming a biased cut for the sleeve seal. The shoulders 90 and the locator post 91 couple the upper mold 99, placing the bearing insert 78 therein. The molten plastic is injected into the mold, forming the plastic box 84. Figures 12 and 13 show a reinforcement 102, which is an alternative embodiment of the reinforcement 42 of the second embodiment of the hinge joint assembly 41. The reinforcement 102 is formed by placing powdered metal in a matrix and subjecting it to high pressure and temperature, instead of stamping. The reinforcement 102 has a shallow container 104 with cut-outs 106 surrounding it. A rod 108 is formed integrally with the shallow vessel. A hexagonal projection 110 is positioned between the rod 108 and the shallow vessel 104. The rod 108 has external threads 112 as well as internal threads 114 formed by machining. If only the external threads are desired, the internal threads 114 need not be machined. If only the internal threads 114 are desired, the external threads 112 can be covered by the plastic case (not shown) to provide protection against corrosion. Yet another variation (not shown) of the reinforcement 102 has a shoulder at the top of the container 104 with an opening therethrough receiving a grease fit for the spherical joint assembly. Preferred embodiments have been described. A worker with ordinary skill in the art would realize, however, that certain modifications could come within the teaching of this invention. For example, it may be advantageous to use a ball bolt having a variant body from the two types shown herein. Additionally, in the embodiments of Figures 1-3 and 9-11, alternative variations in the method of attaching the rod to the reinforcing ring or bearing insert are readily apparent. For example, the parts could be threadably coupled with each other. Additional variations on the precise configuration of the internal and external surfaces of the rod can be easily contemplated. The flanges can be used instead of the threads when appropriate. Solid rods can be used instead of hollow rods, when external threads are desired. There may also be variations in the shapes of the shoulders over the insert linings. The following claims must be studied to determine the scope and true content of the invention. Having described the invention as above, property is claimed as contained in the following:

Claims (20)

1. A spherical hinge assembly for a suspension of a motor vehicle, characterized in that it comprises: a ball bolt having a ball bolt shaft and a body portion and a ball end centered thereon; a plastic bearing shell having an open end placed on the ball end, with the ball end facing the body portion and having a bearing surface in engagement with the ball end and having a plurality of grooves extending from the open end defining a plurality of flexing fingers, which radially flex from a first position to receive the ball end and for the complete insertion of the ball end within the return of the liner to the first position, so they axially retain the ball end in it; a rod having a rod shaft extending radially from the bearing shell and having coupling threads; and a plastic box that wraps around the bearing shell and cooperates with the bearing liner to positively lock the ball end into the bearing shell, by securing the flexible members in the first position, thereby preventing the axial displacement of the bearing. they of the ball bolt.

2. The spherical hinge assembly for the suspension of a motor vehicle according to claim 1, characterized in that: the spherical hinge assembly also includes a metal reinforcement having a receiving surface that engages radially with the fingers of the liner in the first position, so that it keeps the fingers flexible in the first position, and; the reinforcement is fixed to the rod.

3. The ball joint assembly for the suspension of a motor vehicle according to claim 2, characterized in that: the reinforcement is in the form of a ring.

4. The hinge joint assembly for the suspension of a motor vehicle according to claim 2, characterized in that: the plastic bearing liner has a plurality of coupling lugs on the receiving surface, per. which allows a portion of the rigid plastic box to be placed between the reinforcement and the liner.

5. The ball joint assembly for the suspension of a motor vehicle according to claim 4, characterized in that: a position locating post extends from the liner to a surface of the plastic box.

6. The ball joint assembly for the suspension of a motor vehicle according to claim 2, characterized in that: the reinforcement is a shallow vessel that receives the lining and the ball end from a single direction, with the liner engaging the upper part of the container.

7. The hinge-joint assembly for the suspension of a motor vehicle according to claim 6, characterized in that: a depression in the upper part of the container engages with the bearing lining, thereby controlling an axial position of the ball bolt inside the container.

8. The ball joint assembly for the suspension of a motor vehicle according to claim 6, characterized in that: the ball end has a flat surface on an upper end thereof; and the liner has a substantially spherical bearing surface, except in an upper part where the liner and the container are deformed downward, whereby the resistance to pivoting the ball bolt relative to the container increases.

9. The ball joint assembly for the suspension of a motor vehicle according to claim 2, characterized in that: the rod has grooves on an outer surface and the threads on an inner surface with plastic placed on the outer grooves.

10. The ball joint assembly for the suspension of a motor vehicle according to claim 2, characterized in that: the rod has threads on an outside and the grooves on an interior and is filled with plastic on the inside.

11. The ball-and-socket joint for the suspension of a motor vehicle according to claim 1, characterized in that: a rim covers the lining and is connected to it by a plurality of plastic spokes extending between them and also has a Stem transition extending from the flange to the rod.

12. A method for manufacturing a spherical hinge assembly for the suspension of a motor vehicle, characterized in that it comprises the steps of: forming a ball bolt having a ball bolt shaft and a body portion and a ball end centered about him; molding a plastic liner having a bearing surface and one end open to the bearing surface and a plurality of grooves extending from the open end defining a plurality of flexing fingers; placing the open end of the liner against the ball end; pressing the liner against the ball end, so that the "flexing fingers flex radially to receive the ball end, with the fingers returning to a first position by the full insertion of the ball end into the lining, so it retains the ball in it; form a rod that has a rod axis; place the rod and ball bolt assembled and the liner inside a mold; and injecting molten plastic into the mold to form a box wraps the bearing shell and positively catches the ball end inside the bearing shell.

13. The method for forming a spherical hinge assembly for the suspension of a motor vehicle according to claim 12, characterized in that it includes the additional steps of: forming a metal reinforcement configured to circumscribe the bearing shell and engage the shank; and place the reinforcement on the bearing liner and in the mold before the plastic injection into it.

14. The method for forming a ball-and-socket joint for the suspension of a motor vehicle according to claim 13, characterized in that it includes the additional step of: forging the reinforcement in the form of a ring configured to engage the bearing lining of plastic.

15. The method for forming a ball-and-socket joint for the suspension of a motor vehicle according to claim 13, characterized in that it includes the additional step of: stamping the reinforcement in the form if a configured container is to receive in the form of a coupling The plastic bearing liner.

16. The method for forming a spherical hinge assembly for the suspension of a motor vehicle according to claim 13, characterized in that it includes the additional step of: subjecting the powder metal in a matrix to heat and press to form the reinforcement in the shape of a container, the container is configured to receive the plastic bearing shell in a coupled manner.

17. The method for forming a spherical hinge assembly for the suspension of a motor vehicle according to claim 15, characterized in that it includes the additional steps of: supporting the ball bolt; and pressing a pressing tool against the plastic box opposite the ball bolt to form a depression in the box.

18. The method for forming a spherical hinge assembly for the suspension of a motor vehicle according to claim 16, characterized in that it includes the additional steps of: supporting the ball bolt; and pressing a pressing tool against the plastic box opposite the ball bolt to form a depression in the box.

19. The method for forming a spherical hinge assembly for the suspension of a motor vehicle according to claim 17, characterized in that it includes the additional steps of: stamping the container and a rectangular shaped wing plate extending from it as a integral unit; forming threaded lines on at least one side of the wing plate; and winding the wing plate around a mandrel to form the rod.

20. A spherical hinge assembly for the suspension of a motor vehicle, characterized in that it comprises: a ball bolt having a ball bolt shaft and a body portion and a ball end with both centered on the shaft; a plastic bearing liner having an open end placed on the ball end with the open end facing the body portion and having a bearing surface engaging the ball end and having a plurality of grooves extending from the open end defining a plurality of flexing fingers, which are configured to flex so that the fingers are able to flex radially from a first position to receive the ball end and to complete the insertion of the ball end into the lining back to the first position to axially retain the ball end thereon; a rod having a rod shaft extending radially from the bearing shell and having coupling threads; and a plastic box that wraps around the bearing shell and cooperates with the bearing shell to positively lock the ball end into the bearing shell, securing the flexible members to the first 2 (> position, by which the axial displacement from them of the ball bolt is avoided.