GB2400588A

GB2400588A - Non-contact spring guide

Info

Publication number: GB2400588A
Application number: GB0414193A
Authority: GB
Inventors: Gordon K Andersen; Brian K Anderson; Christopher K Yakes; Jon J Morrow; Jesse D Gander; Geoffrey W Schmitz; David W Archer
Original assignee: Oshkosh Truck Corp
Current assignee: Oshkosh Truck Corp
Priority date: 2000-08-08
Filing date: 2001-08-08
Publication date: 2004-10-20
Anticipated expiration: 2021-08-08
Also published as: GB0415369D0; GB2400589A; GB2400589B; GB2400590B; GB0415366D0; GB2400588B; GB0414193D0; GB2400590A

Abstract

A vehicle suspension comprising a frame, a first control arm (32) pivotally coupled to the frame about an axis substantially parallel to the frame, a coil spring (26) captured between the frame and the first control arm (32), and a bumper external to the spring and configured to limit upward pivoting of the first control arm (32). The suspension also comprises an elongated member (28) having a first end portion coupled to one of the first control arm (32) and the frame, a middle portion passing through the coil spring (26) and a second end portion slidably coupled to the other of the first control arm (32) and the frame, wherein the first end portion, the middle portion and the second end portion are axially fixed relative to one another.

Description

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1- 2400588

NON-CONTACT SPRING GUIDE

The present invention relates to large vehicles hatting independent suspensions, such as those which are typically used in military applications and in large municipal vehicles, such as fire trucks. In particular, the invention relates to a flame and independent suspension assembly which allows a vehicle to have better stability by lowering the center of gravity, and better visibility, because a lower drivetrain and hoodline are made possible by providing more room between the main longitudinal members of the vehicle frame.

Military and other emergency vehicles must be designed to extremely demanding specifications. The vehicles must be capable of driving over or through obstacles which only a tactical or emergency operator would attempt. The vehicles must be able to endure corrosive, partially submerge and frequently dirty environments, such as standing water, chemicals or deep mud.

In addition, it is desirable for such vehicles to provide maximum forward visibility and maximum load carrying capacity. One step which has been taken in the design of heavy duty vehicles has been to utilize C-shaped channels as the main frame members. The use of two widely-spaced beams provides a space where various engine, transmission and other essential components can be mounted. Making more space available along the center line of the vehicle frame allows heavy components to be more effectively mounted at a lower elevation which, in turn, lowers the vehicle's center of gravity. Vehicles with low centers of gravity have improved stability. A lower center of gravity in a vehicle provides improved resistance to overturning as the vehicle traverses rough terrain or maneuvers around obstacles at him rates of speed. The improved visibility that results from the lowering of a vehicle's drive train and hoodline allows for safer operation of the vehicle. While the present invention has particular application in the context of frame members which are C-shaped, the invention may be used with frame members having other shapes, such as tubular shapes (rounded and rectangular) and other structurally advantageous shapes.

The present invention is directed to a mounting assembly as set out in claim 1. Preferred features are set out in the subordinate claims 2 to 25.

Other features and advantage of the present invention will be better understood upon a reading of the

following specification, read together with the

accompanying drawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of a pair of front weldments and portions of a front axle constructed in accordance with the present invention; Figure 2 is a second perspective view of the weldments shown in Figure 1 with other suspension components shown adjacent thereto; Figure 3 is a third perspective view of the weldments shown in Figures 1 and 2; Figure 4 is a side-elevational view of a front left hand weldment of the present invention, as configured with no anti-sway bar; Figure 5 is an end view of the weldment shown in Figure 4; Figure 6 is a top plan view of the weldment shown in Figures 4 and 5; Figure 7 is side-elevational view of a rear left-hand weldment of the present invention, as configured for use with an anti-sway bar; S Figure 8 is an end view of the weldment shown in Figure 7; Figure 9 is a top plan view of the weldment shown in Figures 7 and 8; Figure 10 is an exploded perspective view of a lower control arm constructed in accordance with the present invention; Figure 11 is crosssectional view of a bushing assembly of the control arm of the present invention taken along line 11-11 in Fig. 11A; Figure 11A is a top view of a bushing assembly of the control arm of the present invention; Figure 12 is an exploded perspective view of an anti-sway bar assembly made in accordance with the present invention; Figure 13 is an end view of the spring guide bushing shown in Figure 14 made in accordance with the present invention; Figure 14 is a cross-sectional view taken along line 14-14 in Fig. 13 and showing a bushing for a spring guide; and; Figure 15 is a longitudinal cross-section through a spring guide made in accordance with the present invention; and Figure 16 is a perspective view of structural frame elements used in the invention.

Figure 17 is a perspective view of a suspension assembly in which electric motors are held between two side plates of the suspension assembly. - 4 -

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows the Dont portion of a vehicle and its suspension support in relation to a frame rail 2 of a vehicle. A left-hand or first side plate 10 is mounted beneath a leh-hand flame rail (not shown), and a right-hand or second side plate 12 is mounted beneath a right hand frame rail 2. Several bolts are used to connect each of the side plates 10 and 12 to its respective Came rail. A differential 15 with a differential drive connection 14 is connected to each of the side plates 10 and 12. As further shown in Figures 2 and 3, it is clear that the main

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side plates 10 and 12 are joined together by the louver plate 20, bar 22 and differential 15 at the lower portions of the side plates 10 and 12. The side plates shown in Figures 1 through 6 are for a suspension that is not equipped with an anti-sway bar.

Referring now to the first plate 10 shown in Figures 1 through 6, it is comprised of three main components which are welded together. Those components are: a longitudinally extending main plate member 51; a leading end plate 48; and a trailing end plate 50.

Longitudinally extending plate member 51 includes four sections: an upper vertical plate section 52; a horizontal plate section 54; a lower vertical plate section 56; and a lower lip 58.

The upper vertical plate section 52 and:he lower vertical plate section 56 are in a off-set and generally parallel relationship. Extending from the outer face of the upper vertical plate section 52 are three pockets including a shoclc absorber pocket 38 formed by gusset plates 40 and a bearing plate 42, a jounce bumper pocket 61 formed by gusset plates 40 and 46 and jounce bumper plate 62, and a coil spring pocket 39, defined by the end plate 48, gusset plate 46 and coil spring bearing plate 47. A lining lug 44 may be welded to the bearing plate 47 for use in lifting the complete vehicle. The lower vertical plate section 56 has an opening 70 so that a driveshaft, in the form of a half-shaft 16, can extend from the differential 15 to the wheel end 18 (see Figure 1). '& - 5 - As is most clearly shown in Figure 2, the elements of the suspension system are connected to the outer portions of the first side plate 10. The shock absorber 24 extends from the bearing plate 42 to the lower control arm 32. Similarly, the suspension coil spring 26 extends from thelower control arm 32 to the bearing plate 47. In addition, inside the suspension coil spring 26, a spring guide 28 extends from the lower control elm 32 into the spring guide bushing 30 which is bolted to the coil spring bearing plate 47. An upper control arm 34 is connected by a ball joint 37 to an upper portion of the steering knuckle 41. The upper and lower control arms 34 and 32, respectively, are held in place by four control ann mounting assemblies 94, an example of which is more clearly shown in Figure 10 discussed below. The locations of the control arm mounting assemblies for a led-hand side plate 10 can best be seen in Figure 4 wherein upper control ann attachment locations 68 and lower control arm attachment locations 66 are at upper and lower portions of the vertical mounting plate 56. An ear 78 is used to support various system lines, i.e., hoses and wires, etc., which lead to the wheel end 18. A stiffening flange 60 extends from the outer edge of the end plate to provide the plate 50 with increased resistance to buclding.

Figures 7, 8 and 9 show a left-hand side plate lea for use with an antisway bar. In describing the anti-sway bar equipped left^hand side plate lOa, the same reference numerals which are used to indicate portions of the non anti-sway bar front side plate lO which are the same. For example, a coil spring bearing plate 47 extends between an end plate 48 and a gusset 46 to define a pocket 39 for a coil spring (not shown in Figure 7). The left-hand side plate lea includes upper control arm mounting locations 68 and lower control arm mounting locations 66. Gusset plates 40 and shoclc absorber bearing plate 42 define a shock absorber pocket 38. However, an element which is part of the left-hand side plate lOa7 which is not included in the side plate 10 is a bushing pocket 76 and an opening 74 through which extends an anti-sway bar 1 12, more details of which are shown in Figure 12. - 6 -

Figure 10 is an exploded view of a lower control arm assembly. The lower control arm 32 has two control arm mounting assemblies 94, one of which is shown in exploded form on the left side of Figure 10. The lower control arm 32 has a longitudinal axis and a cylindrical bore al one end of the lower control arm 32. The cylindrical bore has an axis transverse to the lower control arm longitudinal axis. The control arm mounting assembly 94 includes a pin 96 and two bushing assemblies 98 (more detail of which is shown in Figure 11. The ends of the pin 96 are clamped by the blocks 36 as the blocks 36 are attached to the lower vertical plate section 56 of a side plate. Each of the blowfly 36 has a central opening and is circumferentially discontinuous about its central opening. The pin 96 has a length greater than the sum of the lengths of the bushings 98 whereby the pin 96 when passing through the bushings 98 has exposed ends grippable by the clamping blocks 36. The pin 96 can have a threaded bare at each end. The clamping blocks 36 each have aligned holes through which bolts may pass, with tightening of the bolts causing the slots 97 to close and the blocks 36 to grip the pin 96. The aligned holes may be unthreaded. A thrust washer 108 is I 5 disposed between each bushing assembly 98 and a block 36. A screw I 10 and washer 111 are used to properly pre-load the bushing assembly 98 before installation. These fasteners are threadably engageable in the threaded bore of the pin 96.The lower control arm 32 includes a spring mount 90 through which there extends a spring pivot pin 91 and a sleeve bearing 95 A spring seat 84, with a threaded hole 85 for receiving the spring guide 28, straddles the spring mount 90. A smal] dowel pin 89 retains the pin 91 in the spring seat 84, and causes the spring seat 84 to rotate the spring pivot pin 91 within the sleeve bearing 95. A pair of seals 93 prevent contaminants from entering the sleeve bearing 95 within the spring mount 9(). Figure 10 also shows a ball joint assembly 82, which is housed within a soclcet 80 on the outer end of the lower control arm 32. - 7 -

Figure I I is an enlarged cross-sectional view of the bushing assembly 98 which is part of the control arm mounting assembly 94. The bushing assembly 98 includes an inner sleeve bearing 106, an intermediate sleeve 104 and an outer elastomeric sleeve 102 which has a flange 107 at one end and annular ribs and grooves on the outside surface thereof A seal S 100 engages a shoulder formed on the outer edge of the intermediate sleeve 104. The bushing assembly 98 fits snugly into a bore formed at the inside end of each leg of the lower control arm 32. As the block 36 is tightened into position against the lower vertical plate section 56 of a side plate, the pin 96 is gripped by the block 36 as a result of the closing of the gap formed by the slot 97 in the block 36. A slot in each block 36 of a control arm mounting assembly allows for easy removal of a pin 96 from the assembly 94. Arranging the slots 97 so that they face down makes it harder for water and mud to flow into the pinlblock joint.

Figure 12 shows the anti-sway assembly.

An anti-sway bar 112 has a splined end 114 and extends through the opening 74 in the upper vertical plate section 52 of a rear side plate 10a. The anti-sway bar 112 is supported by a bushing 116. The bushing 116 is contained in a pocket 76, the top portion of which is formed by a removable plate 124. One end of the plate 124 is inserted into a slot 77 formed in a gusset plate 40, and the other end of the plate 124 is held in place by bolts. A pair of collars 118 maintain the position of the anti-sway bar 112 in the bushing 116. A pair of seals 119 prevent contaminants from entering the bushing 116. The splined end 114 of the anti-sway bar 112 is engaged in and clamped by an end of the arm 120. A vertical link 122 connects an end of the arm 120 to a lug 43 of the steering knuckle 41.

Figures 13 and 14 show the spring guide bushing 30 which is attached to the coil spring bearing plate 47 on the front side plates 10 and 12. The spring guide bushing 30 includes a tapered bore or opening 3l through which a spring guide 98 extends. The taper allows the spring guide 28 to articulate slightly within the bushing 30. Mounting ears 33 - 8 facilitate the connection of the bushing 30 to the bearing plate 47. The bushing 30 is mounted in the orientation shown in Figure 2 so that the narrower end of the tapered opening 31 is upward, i.e., the bushing 30 extends down into and through the opening in the bearing plate 47. The rear spring is stable enough by itself not to need a guide. late spring guide 28 is shown in Figure 15. [he spring guide 28 has a threaded end 27 which threads into the threaded hole 85 in the spring seat 84. (See Figure lO.) A stop 35 is welded to the body of the' spring guide 28 to limit the threaded engagement of the threaded end 27 and the spring seat 84. At the opposite end of the spring guide 28, a drive socket 29 is incorporated to facilitate the threaded engagement of the spring guide 28 into the spring seat 84 with a common wrench. It should be noted that the diameter of the spring guide 28 is substantially smaller than the inside diameter of the coil spring 26 through which it extends. The result is a non-contact spring guide. The spring guide 28 is free to slide within the tapered operung 31 in the spring guide bushing 30 as the wheel of a vehicle moves up and down. The alignment of the spring seat 84, however, is maintained so that buclding of the coil spring 26 is prevented, even in instances where there is a large compression of the spring as a result of relative movement of the wheel and the frame.

Figure 16 shows how the C-shaped main frame members 2 and 4 are tied together without the fUrrnation of holes in the top and bottom flanges thereof. Reinforcing channels 133 and 134 are bolted to the inside of the vertical webs 130 and 131. Angle supports 135 and 136 connect the crossmember 137. In effect, the reinforcing channels 133 provide a horizontal extension of the flanges of the main frame members 2 and 4, and provide a location to which vertical bolts 140 may be used to connect the channels 133 and 134 to the crossmember 137. The crossmember 137 is located just ahead of the rear axle or axles, in the case of tandem rear wheels. 9 -

Also shown in Figure 16 is a front crossmember 150, which is located under the main frame member 2 and 4, leaving room between the Dame members 2 and 4. The front crossmember 15() is, like the rear crossmember, affixed to the main frame members without compromising the structural integrity of those members, as might be the case if holes in top and bottom flanges of the main frame members were drilled to receive connecting bolts.

Large angle plates are bolted to the outside of the main frame members 2 and 4. inwardly extending flanges 153 on large angle members 151 carry the ends of the front crossmember 150. Smaller angles 152 hold the crossmember 150 in place on the flanges 153. An upper angle plate 154 connects the vertical webs 130 and 131 of the main frame members to the smaller angles 152 and to the crossmember 150.

Figure 17 is a perspective view of a suspension assembly in which two electric motors 160 and 162 are mounted between side plates lOb and 12b, rather than a more traditional differential as shown m earlier described embodiments of the invention. This arrangement allows each of the motors to drive one half:shaft and one wheel. the particular example shown in Figure 17, the motors directly drive the half-shafts (not shown). To enhance the structural strength of the assembly, which includes the side plates lOb and 12b, the housings of the motors 160 and 162 may be rigidly connected to one another. However, that if larger motors are used a 90 degree drive box may be inserted and the motors mounted in positions in which they are not disposed between the side plates, but are axially offset with respect to one another. Also in the example shown in Figure 17, the wheels are held in aligned positions relative to the frame by stabilizing bars 164 and 166, although the assembly shown is equally applicable to pairs of wheels which are steered wheels.

lIaving described a number of features, discoveries and principals embodied in the foregoing examples, it is intended and will be understood by those skilled in the art, that a number of modifications, alternatives and variations thereof may be made while still incorporating Me spuit and scope of the inventions as claimed below.

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Claims

Claims: 1. A vehicle suspension comprising a frame, a first control arm

pivotally coupled to the frame about an axis substantially parallel to the frame, a coil spring S captured between the frame and the first control arm, and a bumper external to the spring and configured to limit upward pivoting of the first control arm, characterized in that the suspension further includes: an elongated member having a first end portion coupled to one of the first control arm and the frame, a middle portion passing through the coil spring and a second end portion slidably coupled to the other of the first control arm and the frame, wherein the first end portion, the middle portion and the second end portion are axially fixed relative to one another.
2. A vehicle suspension of Claim 1, wherein the second end portion is slidably coupled to the frame.
3. A vehicle suspension in accordance with Claim 2, wherein the second end portion slidably passes through the frame.
4. A vehicle suspension in accordance with Claim 3 including a bushing coupled to the frame, wherein the second end portion slidably extends through the bushing.
5. A vehicle suspension in accordance with Claim 1, wherein the first end portion is pivotally coupled to the said one of the first control arm and the frame.
6. A vehicle suspension in accordance with Claim 1, wherein the first end portion, the middle portion and the second end portion are integrally formed as part of a single unitary body.
7. A Vehicle suspension in accordance with Claim 1 including a shock absorber coupled between the vehicle frame and the first control arm.
8. A vehicle suspension in accordance with Claim 7 including a wheel end drive shaft extending between the coil spring and the shock absorber.
9. A vehicle suspension in accordance with Claim 1, wherein the elongated member linearly extends between the first control arm and the frame.
10. A vehicle suspension in accordance with Claim 1 including a second control arm pivotally coupled to the frame above the first control arm.
11. A vehicle suspension in accordance with Claim 1 including a shock absorber coupled between the vehicle frame and the first control arm.
12. A vehicle suspension in accordance with Claim 11, wherein a portion of at least one of the first control arm and the second control arm extends between the shock absorber and the elongate member.
13. A vehicle suspension in accordance with Claim 1, wherein the first control arm is configured to be pivotally coupled to a frame about an axis substantially parallel to the frame.
14. A vehicle suspension in accordance with Claim 1, wherein the spring seat is rotatably mounted to the first control arm about an axis parallel to the frame.
15. A vehicle suspension in accordance with Claim 1 including a second control arm pivotally coupled to the frame above the first control arm, a pivotable spring seat rotatably mounted to said first control arm, a coil spring bearing plate carried by the frame above the second control arm, wherein the coil spring extends from the spring seat on the first control arm past the second control arm to the bearing plate, wherein said spring is normally partially compressed by weight of a vehicle between said coil spring bearing plate and said spring seat on said first control arm, and wherein the second end portion extends through an opening in the bearing plate so as to slide relative to the bearing plate.
16. A vehicle suspension in accordance with claim 15 wherein: a bushing is disposed adjacent to said opening, said bushing having a central through-hole aligned with said opening and having mounting flanges at one end mounted to one side of said bearing plate, said through-hole being tapered with one end of said through-hole being larger in diameter than said elongated member, and an opposite end of said through- hole having a diameter smaller than said elongated member, said bushing being comprised of wear-resistant material, whereby said bushing guides said elongated member as said elongated member passes through said bushing.
17. A vehicle suspension assembly in accordance with claim 17 wherein: said elongated member is cylindrical and has an externally threaded first end and wrench engagement surfaces at a second end, said spring seat having a threaded hole, whereby said elongated member may be installed by passing said elongated member through said bushing and using said wrench Engagement surfaces to thread said externally threaded end into rigid supporting engagement with said internally threaded hole in said spring seat.
18. A vehicle suspension assembly in accordance with claim 17 wherein: said elongated member is a hollow tube with internal driving surfaces at one end whereby said tube may be tightened into said internally threaded hold by application of rotative forces to said driving surface.
19. A vehicle suspension assembly in accordance with claim 18 wherein: said tube is smooth on an upper portion of said tube and said bushing is made of a wear-resistant polymeric.

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20. A vehicle suspension assembly in accordance with claim 15 wherein: said coil spring has an inside diameter and said elongated member has an outside diameter, said inside diameter of said coil spring being substantially greater than said outside diameter of said elongated member.
21. A vehicle suspension assembly in accordance with Claim 15, wherein the first end portion, the middle portion and the second end portion are integrally formed as part of a single unitary body.
22. A vehicle suspension assembly in accordance with Claim 15, wherein the elongated member linearly extends from the spring seat to the bearing plate.
23. A vehicle suspension assembly in accordance with Claim 15 including a shock absorber coupled between the vehicle frame and the first control arm.
24. A vehicle suspension assembly in accordance with Claim 23, wherein a portion of at least one of the first control arm and the second control arm extends between the shock absorber and the elongated member.
25. A vehicle suspension assembly substantially as described herein with reference to and as illustrated in the accompanying drawings.