MX2007013888A - Heat shrunken low-friction stabilizer bar sleeve - Google Patents

Abstract

A stabilizer bar for a vehicle suspension includes a sleeve that is heat shrunk around the stabilizer bar. The sleeve is made from a low-friction polymer or thermoplastic material and is first installed on the stabilizer bar in a pre-shrunken state. Heat is subsequently applied to the sleeve to shrink and fix the sleeve to the stabilizer bar. A bushing is then mounted on the sleeve.

Description

LOW FRICTION GUITAR ENCOGED BY HEAT FOR STABILIZER BAR FIELD OF THE INVENTION The present invention relates to a stabilizer bar having a heat shrunk sleeve for mounting a bushing. BACKGROUND OF THE INVENTION Bushings are used to isolate and mount a stabilizer bar to a vehicle structure, such as a vehicle frame and allow rotation of the stabilizer bar. A type of bushing consists of an elastic sleeve made of a material such as rubber, for example. The bushing typically includes an additional structure that is used to reduce friction between the stabilizer bar and the bushing. This structure is modeled, attached, or impregnated in the hub. In a known configuration, the bushings include a Teflon® "zócal or" type liner that is molded, bonded or bonded to an inner surface of an elastic sleeve of a bushing. That kind of linings are expensive | in terms of material prices and processing costs. The cost also rises as a result of the molding tools, which are used to fix the liner to the hub. In another known configuration, a low friction agent, commonly referred to as "slippery rubber" is incorporated into the rubber. It is not desirable to use this type of agent because the material is expensive. In addition this material has proven that it presents Noise problems in certain applications. Thus, there is a need for a more cost-effective mounting configuration for the bushings in a stabilizer bar that overcomes the deficiencies described in the prior art. BRIEF DESCRIPTION OF THE INVENTION A stabilizer bar for a vehicle suspension includes a sleeve that is heat shrunk around the stabilizer bar. A bushing is then mounted on the sleeve. As such, relative rotation can occur between the bushing and the sleeve instead of between the sleeve and the stabilizer bar. This can increase the bushing life and provide a more cost-effective assembly solution. In one example, the sleeve is made of a low friction polymer or thermoplastic material and is first installed on a stabilizer bar in a pre-shrunk state. Subsequently heat is applied to the sleeve to shrink and fix the sleeve to the stabilizer bar. The bushing is subsequently mounted on the sleeve. In one example, the sleeve has a greater axial length than the hub to ensure adequate coverage in the event that a "slip" occurs. The "displacement" is a condition in which the stabilizer bar moves in the axial direction in relation to the bushing. These and other features of the present invention may better understand the following specification and drawings, of which a brief description. Brief Description of the Drawings Figure 1 is a schematic view of a stabilizer bar embodying the present invention. Figure 2A is a side view shown in cross section of a stabilizer bar and a sleeve in a pre-epcoded state. Figure 2B is a side view shown in a partial cross section of the stabilized bar and the sleeve in a shrunken state. Figure 3 is a cross-sectional view taken along line 3-3 as indicated in Figure 2. Figure 4 is a cross-sectional view of another example of a stabilizer bar embodying the present invention. Figure 5 is a cross-sectional view of another example of a stabilizer bar embodying the present invention. Figure 6 is a cross-sectional view of another example of a stabilizer bar embodying the present invention. Figure 7 is a cross-sectional view of another example of a stabilizer bar embodying the present invention. Detailed Description of the Invention A suspension assembly 10, shown in Figure 1, includes a stabilizer bar 12 that can be fixed to a vehicle structure 14 with bushings 16. A clamp 14a is used to mount the bushings 16 to the vehicle structure 14. Two bushings are shown, however a single bushing or a larger number of bushings could be used for certain applications. The stabilizer bar 12 includes opposite ends 18 which can be fixed to laterally opposed suspension components 20, such as control arms on the left and on the right, for example. It should be understood that although the stabilizer bar 12 is generally shown in a C-shaped configuration, the stabilizer bar 12 may include flexed and / or angled portions depending on the desired configuration of the suspension and the application of the vehicle. A sleeve 22 is heat shrunk in the stabilizer bar 12 prior to the installation of the bushing 16. In the example shown each bushing 16 includes a separate bushing 22, however a single bushing could be used to mount multiple bushes. The sleeve 22 has a pre-shrunk state (Figure 2A) and a shrunken state (Figure 2B).

In the pre-shrunk sleeve, the sleeve 22 has a larger diameter i than when it is in the shrunk state. When in the pre-shrunk state, the sleeve 22 can be easily adjusted on the stabilizer bar 12, and can be properly positioned at a desired location to receive the bushing 16. Once it is in the proper position, the sleeve 22 shrinks on the stabilizer bar 12 by means of a brief application of heat by means of a heat source H. The heat source H can be a heat gun or a heat lamp.

I outer surface 30 of the sleeve 22. The bushing is made of elastic material such as rubber, for example, however other types of material can be used. In this configuration, the relative rotation may occur between a rubber-like component, ie the bushing 16, and a plastic-type component, ie the bushing 22. This configuration improves fatigue, reduces costs and reduces noise when compared to configurations. traditional when the relative rotation between the rubber type component has occurred, this is the bushing and the metallic component, this is the stabilizer bar. As shown in Figure 1, at least a portion of the stabilizer bar 12 extends in a lateral direction as length of the axis A. The sleeve 22 has a first axial length L1 extending generally along the lateral axis A. The bushing 16 has a second axial length L2 extending generally along the lateral axis A. The first length The axial displacement L1 is greater than the second axial length L2 (FIG. 2b) to ensure adequate coverage for the "displacement of the stabilizer bar." The "displacement" occurs when the stabilizer bar 12 moves axially in relation to the bushings 16. In In an exemplary embodiment, the sleeve 22 is installed on the stabilizer bar after the stabilizer bar 12 has been painted, see figure 4. In this example, the stabilizer bar 12 includes a layer of paint 36 which is applied to the exterior surface. The sleeve 22 is then installed after painting on the assembly table before the bushings 16 are installed, thus the assembly and the tools are simplified. thoroughly compared to traditional configurations. In an exemplary embodiment, a layer of adhesive 38 is applied to the inner surface 24 of the sleeve 22, see figure 5. This will ensure that there is an airtight seal with the rod 12 to prevent the penetration of moisture or debris. Optionally, a layer of paint 36 and a layer of adhesive 38 could both be used as shown in Figure 6. The present invention of heat shrinking sleeves 22 on a stabilizer bar 12 could also be used to eliminate extra parts and extra tools. Typical heat shrink tubing (used to form sleeve 22) is available with wall thicknesses of 0.020 inches or 0.5 mm. This would add a 1mm diameter to the stabilizer bar 12. It is common to have stabilizer bars with diameters that are very close to each other, such as for example 1 mm in diameter separated from each other. With the present invention, two (2) sleeves 22 can be used instead of a single sleeve 22 to give the difference of 1 mm in diameter. As shown in Figure 7, a first sleeve 22a would shrink on the stabilizer bar 12, and a second sleeve 22b would be chosen by heat on the first sleeve 22a. The 16-inlet bushing would be installed around the second sleeve 22b. A layer of paint 36 (figure 4) and / or a layer of adhesive 38 (figure 5) could also be used with this configuration. Although a preferred embodiment of this invention has been described, a person of ordinary skill in the art will recognize that certain modifications will come within the scope of the invention. For this reason, the following claims should be studied to determine the true scope and content of the invention.

Claims (12)

1. CLAIMS 1. A stabilizer bar assembly comprising: a stabilizer bar; jn sleeve having a thermally shrunk body which is fixed to the stabilizer bar in such a way that there is no relative rotation between the sleeve and the stabilizer bar; and a bushing placed on the sleeve. The stabilizer bar assembly according to claim 1 in which the sleeve includes a pre-shrunk state and a shrunken state having the body shrunk by heat, a sleeve that changes from a pre-shrunk state to the shrunken state after that the sleeve has been assembled on the stabilizer bar. 3. The stabilizer bar assembly according to claim 1 including a layer of paint between an inner surface of the sleeve and an outer surface of the stabilizer bar. 4. The stabilizer bar assembly according to claim 1 including a layer of adhesive between an inner surface of the sleeve and the outer surface of the stabilizer bar. The stabilizer bar assembly according to claim 1 wherein at least a portion of the stabilizer bar extends along the lateral axis, and wherein the sleeve has a first axial length extending generally along the lateral axis, the second axial length is smaller than the first axial length. 6. The stabilizer bar assembly according to claim 1, wherein the sleeve consists of a low friction polymeric material and a thermoplastic material. ' The stabilizer bar assembly according to claim 1 wherein the sleeve consists of one of a PTFE material and an FEP material. 8. The stabilizer bar assembly according to claim 1 in which the bushing consists of an elastic material that directly engages on the outer surface of the sleeve. 9. The stabilizer bar assembly according to claim 1 in which the stabilizer bar has opposite arm ends which are adapted to be mounted on the vehicle suspension components. The stabilizer bar assembly according to claim 1, wherein the hub can be mounted to a vehicle structure. The stabilizer bar assembly according to claim 1, wherein the sleeve comprises a first sleeve and includes a second sleeve having a heat-shrunk body that is fixed to the first sleeve with an internal surface of the hub directly engaged in the hub. outer surface of the second sleeve. 12. A method of assembling a bushing to a bar stabilizer comprising: [a) providing a stabilizer bar; b) heat shrink a sleeve around the stabilizer bar; and c) mounting a bushing around the sleeve. 3. The method according to claim 12, wherein the sleeve has a pre-shrunk state and a shrunken state, and which includes placing the sleeve on the stabilizer bar in a pre-shrunk state and subsequently applying heat to the sleeve. to achieve the shrunken state wherein the sleeve is fixed to the stabilizer bar in such a way that there is no relative rotation between the sleeve and the stabilizer bar. ^ 14. The method according to claim 12 which includes applying a paint layer to the stabilizer bar before step (b). 15. The method according to claim 12 which includes applying an adhesive to the inner surface of the stabilizer bar before step (b). The method according to claim 12 which includes forming the sleeve from a low friction polymeric material and a thermoplastic material. The method according to claim 12 which includes forming the bushing from an elastic material. The method according to claim 12 which includes forming a sleeve of a plastic material and forming the hub from of an elastic material, directly engaging an inner surface of the sleeve against the outer surface of the stabilizer bar, and directly engaging an inner surface of the hub against an outer surface of the sleeve. The method according to claim 12, wherein the sleeve comprises a first sleeve and includes the steps of heat shrinking a second sleeve on the first sleeve and assembles the hub around the second sleeve.