MXPA99001315A - Coupling of stabilizing bar of direct action, plug - Google Patents

Abstract

The present invention provides a suspension structure that includes a pair of end couplings that interconnect the opposite ends of a stabilizer bar with a pair of suspension members. The stabilizer bar has a central segment and arm segments projecting from each end of the central segment. The end couplings interconnect the distal ends of the arm segments with the suspension members. Each distal end of the arm segments includes a shaped axial bore, which is adapted to receive a pin projecting from each end coupling. The spigot cooperates with the axial perforation to provide a secure connection between the stabilizer bar and the end coupling. The axial bore can be internally threaded to receive external threads formed in the end coupling pin. As such, this threaded structure allows the stabilizer bar to be connected to the end link quickly and easily and with a minimum of component

Description

COUPLING OF DIRECT ACTION STABILIZER BAR, FIELD OF THE INVENTION The present invention relates to a suspension system for motor vehicles and more particularly to an end coupling for connecting a stabilizer bar to a control arm of the suspension system. BACKGROUND OF THE INVENTION It is common practice for motor vehicles to be equipped with independent suspension systems to absorb road crash and other vibrations, while providing a uniform and comfortable ride for the occupants of the vehicle. A stabilizer bar is often used to increase rolling stiffness and improve steering stability of the vehicle Typically, the stabilizer bar is a rod-shaped member having an elongated center segment, oriented to extend laterally through the vehicle and a arm segment that is projected a longitudinally at each end of the central segment, to form a structure generally U-shaped. The central segment of the stabilizer bar is held for rotation with respect to its own longitudinal axis by one or more mounting brackets that are fixed to the frame or body vehicle. More commonly, the mounting brackets are placed in immediate proximity to the arm segments to minimize any bending moment that may be introduced to the stabilizer bar. The distal end of each arm segment is coupled to a control arm of the suspension system by an end link. When the vehicle is subjected to a lateral rolling force, such as for example while the vehicle is turning, the arm segments pivot in opposite directions with respect to the longitudinal axis of the central segment. As a result, torsional reaction forces acting through the arm segments are generated to move the control arms in order to move towards their normal position. In this way, the body of the vehicle will be prevented from tilting or rolling excessively on either side due to the torsional resistance produced by the stabilizer bar. As noted, each end of the stabilizer bar is typically connected to a corresponding control arm by an end link. Although a number of means have been proposed to connect the stabilizer bar to the end coupling, to date none have been found acceptable in terms of simplicity and cost reduction. For example, most stabilizer bars must be fabricated with an eye shape at the far end for connection to the end coupling. One attempt to eliminate the requirement for an eye shape in the stabilizer is to provide an end coupling that includes an opening with ring structure formed therein to receive the end of the stabilizer bar arm. However, it has been found that these end couplings are expensive to produce and also compromise the quality of travel of the vehicle by making the feeling of travel harder during normal driving conditions. A trend within the vehicle suspension technique is to use hollow stabilizer bars to reduce weight without sacrificing driving sensation and ride stability. Unfortunately, forming the stabilizer bar as a hollow tube increases the complexity of the connection mechanisms required to connect the end of the stabilizer bar to the end coupling. Furthermore, the hollow construction of the stabilizer bar can also sacrifice the integrity of the connection coupling. A second trend employs a direct-acting end coupling or direct coupling, between the stabilizer bar and the lower control arm. The direct coupling can include a spherical ball structure to adjust the angularity between the stabilizer bar and the control arm, as the suspension travels through its range of motion, while also eliminating the amount of yield that is experienced before the stabilizer bar begins to move the control arm to its normal position during vehicle maneuvers. Although these direct links have experienced enormous success, they still require that the end of the stabilizer bar include an eye shape for connection, therefore, the performance advantages achieved by the direct link are typically depleted by the cost and complexity required for the connection. Therefore, it would be convenient to provide a direct coupling for a hollow stabilizer bar which connects quickly and easily to the end of the stabilizer bar with minimum complexity.DECENDED COMPACT The present invention provides a suspension structure for a motor vehicle that includes a pair of end couplings that interconnect the opposite ends of a stabilizer bar with a pair of suspension members The stabilizer bar has a central segment and arm segments projecting from each end of the center segment. of end interconnect the extre distant from the arm segments to the suspension members. The distal end of each arm segment includes an axial bore which is adapted to receive a pin projecting from each end coupling. The spigot cooperates with the axial perforation to provide a secure connection between the stabilizer bar and the end coupling. As a further feature of the present invention, the axial bore can be internally threaded to receive external threads formed in the end coupling pin. As such, this threaded structure allows the stabilizer bar to be connected to the end coupling quickly and easily and with a minimum of components. BRIEF DESCRIPTION OF THE DRAWINGS In order to appreciate the way in which the advantages and objects of the invention are obtained, a more particular description of the invention will be achieved by reference to specific embodiments thereof that are illustrated in the attached drawings. It will be understood that these drawings only illustrate preferred embodiments of the present invention and therefore should not be considered limiting in scope, the invention will be described and explained with specificity and additional detail through the use of the accompanying drawings, wherein: Figure 1 is a perspective view of an exemplary independent front wheel suspension system in which the present invention is incorporated; Figure 2 is a sectional view of a portion of the suspension system shown in Figure 1, and illustrating a stabilizer bar and direct coupling made in accordance with a preferred embodiment of the present invention; Figure 3 is a partial sectional view showing a modified version of the stabilizer bar and direct coupling shown in Figure 2; Figure 4 is a sectional view of a portion of the suspension system shown in Figure 1, and illustrating a stabilizer bar and end coupling made in accordance with another preferred embodiment of the present invention; and Figure 5 is a sectional view of a portion of the suspension system shown in Figure 1, illustrating a stabilizer bar and end coupling according to yet another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION In general, the present invention is directed to an end coupling for connecting a stabilizer bar to a suspension member such as a control arm in a vehicle suspension. The end coupling of the present invention is adapted to replace most conventional end couplings and work in conjunction with a modified stabilizer bar, to provide improved performance in a vehicle suspension. In this manner, the end coupling of the present invention can be employed with a wide variety of suspension systems and is not intended to be limited to the particular application described herein. Turning now to the drawings, Figure 1 shows an independent front wheel suspension system system, generally indicated at 10, of the type having upper and lower control arms and a post structure on each wheel that is suspended from the frame of the vehicle. vehicle. Reference will be made to a vehicle frame in the present description, however those skilled in the art will recognize that many current vehicles do not have a frame as such but instead have regions of the body that act as an integrated frame structure . With this in mind, the frame 12 is shown to partially include a pair of longitudinal side rails 14 and a cross beam 16. The suspension system 10 includes a long lower control arm 18, and a short upper control arm 20, both pivotally connected to the frame 12. A pole structure having a coil spring 22, and a pole damper 24, are retained between an intermediate portion of the lower control arm 18 and frame 12 to support the weight of the vehicle body and any loads that are transmitted through the lower control arm 18. The upper control arm 20 is connected to the lower control arm 18 by a steering pivot 26. A rotor hub structure 28 is rotatably connected to a spindle portion. (not shown) of the steering pivot 26, such as a wheel and tire (also not shown), can be mounted there. A stabilizer bar 30 is illustrated to include an elongated central segment 32 projecting laterally through the vehicle and a pair of arm segments 34 projecting longitudinally on the vehicle at each end of the central segment 32. The central segment 32 connects rotatably to the rack rails 14 by a pair of mounting brackets 36. A distal end 38 of each arm segment 34 is connected to a corresponding lower control arm 18 by an end coupling 40 made in accordance with the teachings of present invention. With reference to Figures 2 and 3, the end coupling 40 is shown attached to the stabilizer bar 30 at one end and the lower control arm 18 at its opposite end. In general, the components of the end coupling 40 are symmetrical with respect to a horizontal plane, identified by the construction line "A". In fact, the end coupling 40 is assembled from a set of components including two ball joint structures 42, 42 ', which are rigidly interconnected by suitable means such as for example a rod 44. Due to the similarity of The components associated with the ball joint structure 42 'with respect to the components of the ball joint structure 42, their components are identified with the same reference numbers but have a premium designation. The ball joint 42 includes a hollow cylindrical housing 46 fixedly fixed by welding or other conventional means to the rod 44. A disk-shaped end cap 50 is retained in the housing 46 adjacent its spherical wall 52 to define a cavity of receptacle. A hollow spherical sleeve 56 is disposed within the socket cavity and defines a spherical socket 66. The spherical ball structure 42 also includes a spherical pin 58, having a rod segment 60 and a ball segment 62 disposed in the socket 66 and retained by a spring retainer 64 secured to the housing 46. The retainer 64 includes a central opening for cooperating with an outer surface of the ball segment 62. A seal sleeve 68 circumscribes a ball segment 62 and can be secured to the housing 46. by bolts or other conventional means. With continued reference to Figures 2 and 3, the stabilizer bar 30 is shown to include an axial bore 70 therein formed. In the illustrated embodiment, the stabilizer bar 30 is of the hollow type that is preferred in the present invention. However, the person skilled in the art will appreciate that axial drilling 70 can also be formed at the terminal end of a solid stabilizer bar by drilling or tapping. To provide means for clamping the ball rod 58 to the stabilizer bar 30, external threads 72 are made in the rod 60 in internal threads 74 formed in the axial bore 70 of the stabilizer bar 30. The ball rod 58 is tightened over the stabilizer 30 a preselected distance or until a plate 76 engages the end 78 of the stabilizer bar 30. As an alternative, the ball rod 58 does not require screwing into the axial bore 70, but instead may be retained by welding or by simply folding the distal end 78 to create a lip flange.

As an alternative to the embodiment illustrated in Fig. 2, Fig. 3 illustrates an end adapter 80 welded to the distal end 78 of the stabilizer bar 30. The end adapter 80 includes an axial bore 82 having internal threads 84. As such , the external threads 72 formed in the rod 60 of the ball stud 58 can be threaded into internal threads 64 formed in the axial bore 82 of the end adapter 80 for clamping the ball stud 58, with the stabilizer bar 30. As can be seen , the end adapter 80 is ideally suited for use in conjunction with a solid type stabilizer bar. It will also be noted that any typical welding methods, including friction welding or laser welding, are within the contemplated scope of this invention. As noted, the end coupling 40 is adapted for connection between the control arm 18 and the stabilizer bar 30. For this purpose, and as illustrated in Figure 2, a bore 86 is formed in a bracket 88 projecting from the lower control arm 18. The threaded rod 60 'of the ball stud 58' is then inserted through the bore 86 in the bracket 88. A convenient fastener, such as a locknut 90, is threaded onto the 60 'threaded rod and tightens at a convenient torque level. Alternatively, the perforation 86 may include internal threads to cooperate with external threads 72 'in the rod 60'. At this point, the end coupling 40 is clamped between the arm segment 34 of the stabilizer bar 30 and the lower control arm 18. An end coupling 140 according to another embodiment of the present invention, is illustrated in the Figure 4, wherein similar components are identified by like reference numbers used to describe the end coupling 40. In general, the end coupling components 140 are substantially similar to those of the end coupling 40, except that the arm segments 34 they are not shown to include a perforation 142. The perforation 142 includes internal threads 144 which are adapted to engage with external threads 62 in the rod 60 of the ball stud 58. Accordingly, the end coupling 140 is joined with a derived eye shape 146 of the stabilizer bar 30. As such, the end fitting 140 can be used in retroactive modification applications to existing vehicle suspensions originally equipped with prior art stabilizer bars to allow design flexibility for the suspension engineer.

Now with reference to Figure 5, an end coupling 240 made according to yet another embodiment of the present invention is illustrated. Unlike the previous embodiments, the end coupling 240 is assembled from a pair of elastomeric bushings 242 and 242 'fixed (ie welded) to opposite ends of a rod 244. Specifically, the elastomeric bushing 242 includes a hollow housing 246, within which an annular rubber bushing 248 is retained. The bushing 248 is mounted on an end portion. 250 of the stabilizer bar . A threaded fastener 252 passes through an interlocking washer 254, such that its external threads 256 engage internal threads 64 in an arm segment 34 of the stabilizer bar 30. The embodiment illustrated in Figure 5 also shows another feature of the present invention. That is, the stabilizer bar 30 includes an extruded end 250 that has a reduced diameter as compared to the remainder of the arm segment 34 of the stabilizer bar 30. When extruding the end 250 of the stabilizer bar At a preselected diameter, the stabilizer bars having different diameters can be manufactured to include a standard size end 250, to cooperate with a standard size threaded rod 60 of the ball rod 58 or a threaded pin 252. While the pin 252 it is shown that it threadably couples the axial bore 60, the bolt 252 can also be welded, with or without threads, or joined by another method now known or further developed, without deviating from the present invention. In addition, the bolt 252 can couple an end adapter welded to the stabilizer bar 30, as illustrated in Figure 3. As opposed to prior art end coupling using specialized components in order to provide connection between the stabilizer bar and the stabilizer bar. the end coupling, each end coupling of the present invention described herein uses an arrow that cooperates with a bore formed at the distal end of the stabilizer bar. An advantage of this end coupling is that there is no need for additional parts such as locking nut or the like, as used in the prior art. As such, the present invention is designed such that there is minimal complexity and lower costs. As a result of the currentilinear design, the manufacturing time and total cost are reduced and a very small space is consumed within the lower part of the vehicle body. Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the present invention can be increased in a variety of ways. For example, the threads of the ball-and-socket pin can be formed as self-derivatives to eliminate the need for forming the perforation at the distal end of the stabilizer bar. Therefore, while this invention has been described in connection with particular examples thereof, the actual scope of the invention should not be limited as such, since other modifications will be apparent to those skilled in the art before a study of the invention. the drawings, of the specification and the following claims.

Claims (25)

1. CLAIMS 1. An end coupling adapted to interconnect a stabilizer bar with a suspension member within a vehicle suspension system, the end coupling is characterized in that it comprises: a first joint structure having a rod segment that threadably couples a Distant end of the stabilizer bar; a second joint structure coupled to the suspension member; and a connector interconnecting the first joint structure with the second joint structure to transmit force between the stabilizer bar and the suspension member, while allowing angular movement therebetween. The end coupling according to claim 1, characterized in that the first joint structure comprises: a ball-and-socket joint including a segment of ball and segment of rod; a housing defining a cavity and coupling with the connector; and a support mechanism for pivotally supporting the ball joint segment within the cavity. The end coupling according to claim 2, characterized in that the rod segment of the ball stud has external threads which threadably couple the internal threads formed in a bore at the distal end of the stabilizer bar. The end coupling according to claim 1, characterized in that the connector has a rod for interconnecting the first joint structure and the second joint structure. The end coupling according to claim 1, characterized in that the stabilizer bar includes an axial bore therein formed for threadedly receiving the rod. The end coupling according to claim 1, characterized in that the stabilizer bar includes a radial bore formed therein for threadedly receiving the rod. The end coupling according to claim 1, characterized in that the rod segment threadably couples an axial bore formed in an end adapter fixedly fixed to the distal end of the stabilizer bar. The end coupling according to claim 1, characterized in that the arrow segment threadably couples an axial bore formed in an extruded end portion of the stabilizer bar, the extruded end portion has a preselected diameter independent of that of a rest of the stabilizer bar. 9. An end fitting adapted for use in a vehicle suspension system for interconnecting a stabilizer bar and a suspension member, the end coupling is characterized in that it comprises: a first ball stud having a first rod segment and a first patella segment; a first housing defining a cavity into which the first ball segment is rotatably held; a second ball stud having a second rod segment and a second ball segment; a second housing defining a cavity within which the second ball segment is rotatably held; a connector interconnecting the first housing and the second housing; the first segment of the rod of the first ball stud engages a threaded hole that is formed at a distal end of the stabilizer bar; and the second rod segment of the second ball stud is fixed to the suspension member. The end coupling according to claim 9, characterized in that the bore is formed axially within the stabilizer bar. 11. The end coupling according to claim 10, characterized in that the bore is formed radially in the stabilizer bar. 12. The end coupling according to claim 10, characterized in that the bore is formed axially through a discrete connection adapter fixedly fixed to the distal end of the stabilizer bar. 13. The end coupling according to claim 10, characterized in that the stabilizer bar includes an extruded end having a preselected diameter independent of a diameter of the remainder of the stabilizer bar and wherein the threaded bore is formed in the extruded end. 14. An end fitting adapted for use in a vehicle suspension for interconnecting a stabilizer bar and a suspension member, the end coupling is characterized in that it comprises: a first bolt having a first segment of rod and a first segment of head; a first elastomeric bushing defining a through opening and within which the first segment of the rod is held; a second bolt having a second segment of rod and a second segment of head; a second silent block loop defining a through opening within which the second segment of the rod is held; or a connector that interconnects the first silent block bushing and the second silent block bushing; the first rod segment threadably couples a bore formed at a distal end of the stabilizer bar; and the second rod segment of the second bolt is fixed to the suspension member. The end coupling according to claim 14, characterized in that the bore is formed axially at a distal end of the stabilizer bar. 16. The end coupling according to claim 14, characterized in that the bore is formed radially through a distal end of the stabilizer bar. The end coupling according to claim 14, characterized in that the perforation is formed axially through a connection adapter that is fixedly fixed to the distal end of the stabilizer bar. The end coupling according to claim 14, characterized in that the bore is formed in an extruded end portion of the stabilizer bar having a preselected diameter independent of a diameter of the rest of the stabilizer bar and where the bore is form at a distal end of the extruded end portion of the stabilizer bar. 19. A suspension system for a motor vehicle, characterized in that it comprises: a stabilizer bar including a perforation formed at a distant end; a suspension member; and an end coupling interconnecting the stabilizer bar and the suspension member, the end coupling includes a first joint structure interconnected with a second joint structure, and wherein one of the first joint structures is attached to the stabilizer bar , by tapping a portion of the rod with the bore and the other of the joint structures is attached to the suspension member. The suspension system according to claim 19, characterized in that the first joint structure includes a ball joint structure and the rod is a rod segment of a ball joint of the ball joint structure. 21. The suspension system according to claim 19, characterized in that the first joint structure further comprises an elastomeric bushing structure and the rod is a rod segment of a bolt of the elastomeric bushing structure. 22. The suspension system according to claim 19, characterized in that the perforation is formed axially within the distal end of the stabilizer bar. The suspension system according to claim 19, characterized in that the perforation is formed radially through the distal end of the stabilizer bar. 24. The suspension system according to claim 19, characterized in that the perforation is formed axially through a connection adapter that is fixedly fixed to the distal end of the stabilizer bar. The suspension system according to claim 19, characterized in that the perforation is formed axially through an extruded end of the stabilizer bar, the extruded end has a preselected independent diameter and a diameter of the remainder of the stabilizer bar.