MXPA97000729A - Adjusta torque pivot joint - Google Patents

Abstract

The present invention relates to an adjustable torque pivot joint, characterized in that it comprises: a housing having a portion that is internally screwed to a deformable lip, a short pin having a ball hutch that is retained in the housing, so such that the short pin rotates and angled with respect to the housing, a first bearing seat in the housing engaging one end of the ball head of the short pin, a second bearing seat in the housing engaging an opposite end of the housing. the ball head of the short pointer, and a threaded plug which threadably couples the internally threaded portion of the housing and which has an oval, outwardly oriented, peripheral tool coupling surface for screwing the screw cap to an adjusted position in the housing , in such a way that the bearing seats are directed in coupling with the ball head, with torque characteristics Convenient orientation, and the deformable lip engages and circulates the outwardly facing surface of tool coupling of the plug in a deformed state, to maintain and prevent tampering of the adjusted position of the screw cap

Description

ADJUSTABLE TORQUE PIVOT JOINT This is a continuation-in-part of the US Patent Application. No. 08 / 595,659 filed February 2, 1996. BACKGROUND OF THE INVENTION This invention relates generally to pivot joints and more particularly to pre-loaded pivot joints, which have a ball rod that rotates and angles with respect to the housing of board. These pivot joints are typically used in automotive steering joint systems. The known pre-loaded pivot joint comprises a ball rod having a ball apparatus disposed in a seal housing with a closed end and coupled by a ball joint which is telescopically inserted into an open end of the joint housing. The ball seat is then pushed against the ball wall to compress a preload spring on the opposite side of the ball head. The ball seat is then retained in this preload position by oscillating the open end of the seal housing inward against a hexagonal portion of the ball seat. The oscillation operation results in high torque characteristics, which require a secondary operation, wherein the outer wall of the wall of the joint housing is folded inward at several circumferentially spaced locations, to reduce the torque characteristics to an acceptable level.

The patent of the U.S.A. 3,892,336 granted to Edward J. Herbernar on June 24, 1975, shows a somewhat similar arrangement. The Herbernar Patent discloses a ball joint wherein a lug is telescopically inserted into the open end of the ball joint housing and pushed with the entire helical spring to pre-load the pivot joint as illustrated in Fig. 1 of FIG. Herbernar patent. The housing then swings inward against male threads on the periphery of the plug to lock the plug in place as illustrated in Figure 2 of the Herbernar patent. The Herbernar ball joint has more or less the same disadvantage as the known pivot joint described previously. That is, the oscillation operation results in high torque characteristics. The Herbernar Patent does not specify a secondary folding operation to relieve pre-loading. By contrast, the Herbernar ball joint provides subsequent adjustment of the screw cap after the operation after the oscillation operation. The adjustment after the fact still requires a secondary operation and furthermore the arrangement does not prevent undue manipulation with the characteristics of desired torsion torque, once the adjustment is made. The U.S. Patent No. 4,187,033 issued to Leonard J. Zu ows i discloses a variable preloaded ball joint assembly, comprising a screw cap or disk. The threaded plug is screwed into the ball joint housing to a pre-load position where axially presses an elastomeric element toward the ball end, with sufficient force to provide a predetermined preload of the ball end as described in FIG. column 3, lines 39-45 of the Zuko ski patent specification. After the disc is properly positioned for proper preload, it is locked in position against rotation by engaging the threads through a side opening in the housing, as illustrated in Figure 3 in the Zukowski patent. This arrangement has several advantages. First, the arrangement requires a lateral opening that tends to weaken housing and introduce seal problems. The second, the retention is relatively weak, as evidenced by the fact that the disc only requires to withstand the preload force before installation of the ball joint. Alternatively, three interlocking chemicals can be used in accordance with column 3, lines 55-66 of the Zukowski patent specification. However, in any event, an elongate housing is required for the threaded end of a support bar that is required to support the compressive forces during operation of the ball joint in steering linkage system. British Patent Specification 753,234 published July 18, 1956, discloses a ball joint comprising a movable ball seat in a housing that is held against the ball head of a rod by a plate-type plug that is screwed into the bottom of the accommodation. The plug has an annular groove that supports a compression spring, which engages the movable ball seat to compensate for wear. The bottom face of the plug has a diametral groove. When the stopper is positioned to perform the desired pressure on the ball head, edge portions of the housing are hammered into the ends of the diametral slot to prevent the stopper from rotating in the housing. This arrangement also has several disadvantages. First, the inter-locking of the plug with the housing is relatively weak as evidenced by the fact that the hammering at the bottom of the housing can be removed in such a way that the plug can be re-adjusted. Still further, the diametral groove of the plug and the hammered portions of the housing are fully exposed and consequently, the tight torque characteristics of the gasket can be unduly manipulated in an easy manner. SUMMARY OF THE INVENTION The object of this invention is to provide a pivot joint with adjustable torque which is compact, resistant and prevents tampering. A feature of the invention is that the adjustable torque pivot joint has a threaded plug that is threaded into the joint housing to provide the proper torque characteristics and then retain in a position adjusted by an oscillating operation that provides strong inter-locking between the screw cap and the seal housing. Another feature of the invention is that the pivot joint with adjustable torque has a threaded plug, which is adjusted to provide the proper torque characteristics and then held in the adjusted position as the housing swings inwardly to engage an oval portion of the ball stopper. Yet another feature of the invention is that the adjustable torque pivot joint has a threaded plug which is held in a position adjusted to provide the proper torque characteristics, by oscillating the housing inwardly to engage and deactivate a portion of the torque. plug tool coupling. Yet another feature of the invention is that the adjustable torque pivot joint has a threaded plug to provide suitable torque characteristics that are maintained in a position adjusted to deformed proportions of a housing that is easy to seal. Yet another feature of the invention is that the adjustable torque pivot joint has a threaded plug, to provide suitable torque characteristics that are maintained in a tamper-proof position adjusted by deformed portions of the housing.

BRIEF pfiSCRJpCIpN pE. The above and other objects, features and advantages of the invention will be more apparent from the following description, which is taken in conjunction with the accompanying drawings in which similar references are to like parts and wherein: Figure 1 is a view in elevation in partial section of a pre-loaded pivot joint according to the invention after finishing the manufacture; Figure 2 is an elevation view in partial section of a pre-loaded pivot joint according to the invention during a manufacturing step; Figure 3 is a section taken substantially on line 3-3 of Figure 2 looking in the direction of the arrows; Figure 4 is an elevation view in partial section of a second pre-loaded pivot joint according to the invention during a manufacturing step; Figure 5 is a section taken substantially on line 5-5 of Figure 4 looking in the direction of the arrows; Figure 6 is a section similar to Figure 5 showing the second pre-loaded pivot joint of Figure 4 at a later stage of manufacture; and Figure 7 is a section taken substantially on line 7-7 of Figure 6, looking in the direction of the arrows. DESCRIPTION OF THE INVENTION Now with reference to the drawings, Figures 1, 2 and 3 illustrates the pivot joint 10 of the invention comprising a housing 12 and a rod 14 that rotates and angles with respect to the housing 12. The housing 12 has an open end 16 which is internally threaded at 18 and a closed end 20. The end Closed 20 includes an external connector 22 in the form of a threaded rod for connecting housing 12 with another member of a steering linkage system (not shown). The rod 14 has a ball head 24 at the end of the rod 26. The ball head 24 is disposed within the housing 12, wherein the free or round end of the ball head 16 engages a disc-type bearing seat 28. The bearing seat is disposed at the closed end of the housing 12 and engages the spring 30 in the form of a Belleville washer which is trapped between the bearing seat 28 and the end wall of the housing 12. The pivot joint 10 further includes an annular bearing seat 32 engaging the opposite end of the ball head 24 which is fused to the rod 26. The annular bearing seat 32 is an integral part of an annular plug 33. The plug 33 has a cylindrical wall which has external threads 34 that couple the internal threads 18 of the housing 12. The plug 33 also includes a hexagonal portion 36 that is well within the profile of the cylindrical wall that is threaded at 34, as best illustrated in the Figure 2. The open end 16 of the housing 12 has a lip 38 that deforms radially inwardly in the hexagonal portion 36 of the plug 33. The pre-loaded pivot joint further includes a seal an elastomeric sleeve seal 40, having a fixed end by clamp to a round median portion of the housing 12 on the deformed lip 38. The opposite end of the sleeve seal 40 is clamped to a round portion of the rod 26. The pivot joint 10 is initially assembled with the lip 38 in a non-conforming state. deformed, that is the lip 38 is configured such that the plug 33 and the integrated annular bearing seat 32 can be screwed into the threaded end of the housing 12, as illustrated in Figure 2. As the cap 33 is screwed into the open end of the housing 12, the annular bearing seat 32, pushes the ball head 24 against the bearing seat 28 by compressing the spring 30 to pre-load the pivot joint 10. The plug 33 is threaded into the open threaded end of the housing 12, until the desired preload is achieved, which in turn provides the desired torque characteristic of the pivot joint 10. This adjusted position of the annular threaded plug 33 is then maintained by permanently deforming the lip 38 of the metal housing 12, radially inward, as illustrated in Figure 1. The hexagonal portion 36 is used to thread the annular bearing seat 32 into the housing 12 during initial assembly and during the adjustment process. The hexagonal portion 36 provides a tool engaging surface such that the plug 33 with its integral bearing seat 32 can be threaded into the machine housing 12 as well as manually. Furthermore, the deformed lip 38 not only maintains the fit but also covers the flat surfaces of the hexagonal portion 36 and traps the corners between the flat surfaces such that the fit is against tampering. Now with reference to Figures 4, 5, 6 and 7 of the drawing, a second pivot joint 110 of the invention is illustrated, comprising a housing 112 and a rod 114 that rotates and angles with respect to the housing 112. The housing 112 has an open end 116 that is internally threaded at 118 and a closed end 120. The open end 116 is initially defined by a cylindrical, unthreaded, deformable lip of circular cross section as illustrated in Figures 4 and 5. The closed end 120 includes an external connector 122 in the form of a threaded rod for connecting the housing 112 to another member of a steering linkage system (not shown).

The short pin 114 has a ball head 124 at the end of a rod 126. The ball head 124 is disposed within the housing 112 where the round free end of the ball head 116 engages a bearing seat 128. The bearing seat is disposed at the closed end of the housing 112 and engages the spring 130 in the form of a Belleville washer which is trapped between the bearing seat 128 and the end wall of the housing 112. The pivot joint 110 further includes a annular bearing seat 132 engaging the opposite end of the ball head 124 that is melted or fused to the rod 126. The annular bearing seat 132 is an integral part of an annular plug 133. The plug 133 has a cylindrical wall having external threads 134 which engage the internal threads 118 of the housing 112. The annular plug 133 also includes a tool engaging portion 135, which separates radially inward from and well inwardly. of the profile of the cylindrical lip 119 in its original non-deformed state as best illustrated in Figures 4 and 5. The tool coupling portion 135 has a concentric perimeter wall which is generally hexagonal, comprises 6 curved portions 136 which are equally spaced in circumferential sense and preferably are equal concentric arc segments. The arc segments 136 are joined by 6 flat sides or equal circumferentially spaced rope segments 138. The curved portions or arc segments 136 remove the sharp corners of a regular hexagon and reduce the radial spacing of the 6 flat sides 138 from a cylinder signed up. This provides an advantage in deactivating the tool coupling portion 135 as explained below. The outer edge 139 of the tool engaging portion 135 is preferably chamfered such that the end surface has beveled surfaces 140, located outside an imaginary circular cylinder inscribed by the 6 flat sides or rope segments 138. These surfaces bevels 140 eliminate sharp edges between the end surface and the perimeter wall of the tool coupling portion 135, to facilitate deformation of the cylindrical lip 119. The pivot joint 110 is initially assembled with the lip 119 in an undeformed state, these are , the lip 119 is configured as a cylinder of circular cross section, such that the annular plug 133 can be threaded into the threaded end of the housing 112, as illustrated in Figures 4 and 5. As the annular plug 133 is threaded into the open end of the housing 112, the annular bearing seat 132 pushes the ball head 124 against the bearing seat 128, com the spring 130 for pre-loading the pivot joint 110. The plug 133 is threaded into the open threaded end of the housing 112, until the desired pre-loading is achieved which in turn provides the convenient torque characteristic of the pivot joint 110. This adjusted position of the annular threaded plug 133 is then maintained by permanently deforming the cylindrical lip 119 of the metal housing 112, radially inwardly by an oscillating operation that progressively reduces the entire cylindrical wall and the diameter of the lip 119, substantially uniformly in tight wedge engagement with the tool coupling portion 135 as illustrated in Figures 6 and 7. In this manner, the upset lip converges in spherical or conical shape to a reduced diameter end position 142 of circular cross-section, engages the lips arc segments 136 to provide a strong inter-locking between the housing 112 and the annular plug 133 which maintains the adjusted position of the plug 133. The arc segments 136 preferably fit into the reduced diameter end portion 142 of the upset lip. The tool coupling portion 135 is initially separated from the undeformed cylindrical lip 119 as illustrated in Figures 4 and 5 and is employed to thread the annular plug 133 into the housing 112 during initial assembly and during the adjustment process., either manual or machine. However, after the adjustment is completed, the reduced end or diameter portion 142 of the upset lip 119 fixes the position of the plug 133 to maintain the fit and also deactivates the tool engaging portion 135, such that the adjustment It is against tampering. To achieve deactivation, the upset lip 119 substantially covers the tool engaging position 135 and prevents access to the tool. Spaces can and do occur between the flat sides 138 and the juxtaposed reduced diameter end portion 142. However, these spaces are not large enough to allow the use of conventional tweezers, keys or nut tightening tools. Furthermore, as indicated above, the arc segments 136 reduce the size of the spaces and the spaces can be reduced to a size that avoids any tool access for all practical purposes, simply by increasing the length of the arc segments. The pre-loaded pivot joint 110 further includes an elastomeric sleeve seal (not shown) having one end clamped to a round median portion of the housing 12, equipped with a seal mounting groove 144 and an opposite end held by clamp to the round portion of the rod or short pin 126.

In each of the particular embodiments described above, the annular bearing seats 82, 132 are an integral part of the annular adjustment plug 33 or 133. This is the preferred arrangement because it reduces complexity and expense. However, the annular bearing seat 32 or 132 and the plug for annular adjustment 33 or 133 can be made as separate pieces. Still further, while the tool engaging portions 36 and 135 of two particular shapes have been illustrated, other oval shapes such as a polyhedron or a round cylinder with any number of flat surfaces are also possible. In addition, the pivot joint may use another type of wear replacement spring instead of the Belleville washer illustrated, or provide for the use of a spring to prevent complete wear, in which case one of the bearing sites may be an integral part of housing 12 or 112. In other words, the invention has been described in an illustrative form and it will be understood that the terminology that has been employed is intended in the nature of descriptive words rather than limiting. Obviously, many modifications and variations of the present invention in light of the above teachings can be realized. Therefore, it will be understood that within the scope of the appended claims the invention may be practiced in another form than that specifically described.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

Claims (17)

1. CLAIMS 1. Adjustable torque pivot joint, characterized in that it comprises: a housing having a portion that is internally threaded and a deformable lip; a rod having a ball head which is retained in the housing, such that the rod rotates and angles with respect to the housing, a first bearing seat in the housing engaging one end of the ball head of the rod, second bearing seat in the housing engaging an opposite end of the ball head of the rod, and a threaded plug threadably engaging the internally threaded portion of the housing and having an oval, peripheral tool engaging surface for screwing the member threaded to a position adjusted in the housing, such that the bearing seats are directed in engagement with the ball head, with suitable torque characteristics, and the deformable lip engages the tool coupling surface of the plug in a deformed state, to maintain the adjusted position of the screw cap.
2. 2. The adjustable torque pivot joint as described in claim 1, characterized in that the second bearing seat is an integral part of the threaded plug.
3. 3. The adjustable torque pivot joint as described in claim 1, characterized in that the deformable lip deactivates the tool engaging surface in the deformed state to prevent tampering with the adjusted position of the threaded plug.
4. 4. The adjustable torque pivot joint as described in claim 3, characterized in that the tool coupling surface is generally hexagonal.
5. 5. The adjustable torque pivot joint as described in claim 3, characterized in that the tool coupling surface comprises a plurality of curved, circumferentially spaced surfaces which are engaged by the deformable lip in the deformed state and a plurality of flat walls circumferentially spaced.
6. 6. The adjustable torque pivot joint as described in claim 3, characterized in that the deformable lip substantially covers the tool engaging surface in the deformed state.
7. 7. The adjustable torque pivot joint as described in claim 6, characterized in that the deformable lip is a cylinder of circular cross section and the deformable lip is deformed radially inward to provide a small end portion of diameter. circular cross section that engages the tool coupling surface.
8. 8. - An adjustable torque pivot joint, characterized in that it comprises: a housing having a closed end, an open end, an internally threaded portion and a deformable lip at the open end, a short pin having a stem and a head of ball at the end of the rod which is retained in the housing, such that the rod rotates and angles with respect to the housing, a disk-type bearing seat at the closed end of the housing engaging one end of the ball head of the housing. shank, a spring disposed between the disc-type bearing seat and a wall at the closed end of the housing, an annular bearing seat in the housing engaging an opposite end of the ball-head of the rod adjacent to the shank, the bearing seat annular has a cylindrical surface with external threads that couple the internally threaded portions of the housing when the annular bearing seat is threaded into the housing, the annular bearing seat has an oval portion, for screwing the annular bearing seat into the housing, for positioning the annular bearing seat at a desired location in the housing, the deformable lip substantially engages the oval portion of the annular bearing seat, when deformed to maintain the position of the annular bearing seat at the desired location, and the deformable lip substantially covers the oval portion of the annular bearing seat in the deformed condition to prevent tampering with the adjusted portion of the annular bearing seat.
9. 9.- The adjustable torque pivot joint as described in claim 8, characterized in that the oval portion is a peripheral surface that is spaced radially inward from the externally threaded portion of the annular bearing seat in the radial direction and the The deformable lip deforms radially inwardly in engagement with the peripheral surface in a plurality of circumferentially spaced sites.
10. 10. The adjustable torque pivot joint as described in claim 9, characterized in that the peripheral surface of the oval portion has a plurality of plane surfaces circumferentially spaced between circumferentially spaced locations.
11. 11. A method for adjusting the torque of a pivot joint, characterized in that it comprises: providing a housing having an open end, an internally threaded portion and a deformable lip at the open end, providing a first bearing seat in the housing, inserting a short pin having a rod and a ball head at the end of the rod into the open end of the housing, such that the ball head of the rod is disposed in the housing and engages the first bearing seat, providing a second bearing seat and a plug having a cylindrical surface with external threads for coupling the internal threads of the housing and an oval portion for screwing the plug into the housing, screwing the plug into the open end of the housing, in such a way that the second bearing seat engages an opposite end of the ball head to retain the ball head in the handle housing As the rod rotates and angles with respect to the housing, it continues to screw the plug into the housing until the member is positioned in a position fitted in the housing to bypass the second bearing seat in engagement with the opposite end of the head. ball, and deforming the deformable lip in engagement with the oval portion of the plug, to maintain the adjusted position of the member and to deactivate the oval portion to avoid tampering with the adjusted portion of the plug.
12. 12. Method according to claim 11, characterized in that the deformable lip substantially covers the oval portion of the cap when it is deformed to avoid undue manipulation with the adjusted position of the member.
13. 13. Method according to claim 12, characterized in that the deformable lip is a cylinder of circular cross section, the oval portion is separated radially inward from the externally threaded portion of the cap in the radial direction and the deformable lip is radially deformed inward, to provide a reduced diameter end portion of circular cross section which couples the oval portion of the stopper in a plurality of spaced locations.
14. 14. Method according to claim 12, characterized in that the oval portion is a peripheral surface having a plurality of plane surfaces circumferentially spaced.
15. 15. Method according to claim 12, characterized in that the oval portion is a generally hexagonal surface.
16. 16. Method according to claim 12, characterized in that the cap is an integral part of the second bearing seat. Method according to claim 12, characterized in that a spring is inserted in the open end of the housing, such that the spring engages one of the bearing seats and directs one of the bearing seats in engagement with the head of the bearing. ball. SUMMARY OF THE FIXED IH A pre-loaded pivot joint has a threaded ball seat, which is threaded into an open end of the joint housing, to adjust the axial load of the ball rod and consequent torque characteristics. The adjusted position of the ball seat is then maintained as the joint housing swings inward to engage a hexagonal position of the ball seat that is used to thread the seat into the housing.