Referring to
The guide pin 102 may include a head portion 110, an elongated stem 112 and a flange 114. The flange 114 may be positioned adjacent to the head portion 110 of the pin 102 to restrict the distal portion of the pin 102 from penetrating the bore 106 beyond a predetermined depth. Optionally, a lower bushing 116 may be coaxially disposed over a portion of the stem 112. For example, as shown in
The lower bushing 116 may be formed from a material that is biased radially outward to engage the bore 106 when the guide pin 102 is disposed within the bore 106, as shown in
Referring to
In one aspect, the inner radial layer 122 may be bonded to the outer radial layer 124 by an adhesive. However, those skilled in the art will appreciate that the inner and outer layers 122, 124 may be connected using any available technique, or, alternatively, not physically connected or bonded at all.
The bore 106 may have various geometries and may be formed in the body 108 by any available means, such as drilling, machining, cutting or the like. Referring to
Those skilled in the art will appreciate that the upper bushing 104 may be inserted into the first portion 128 of the bore 106 by any available means, such as press fitting. In one aspect, the upper bushing 104 may have an axial length of about 6 to about 14 mm.
Thus, the bore 106 may be pre-filled with a lubricant (e.g., grease) such that when the stem 112 of the guide pin 102 is positioned in the bore 106, the rigid inner layer 122 of the upper bushing 104 is closely and coaxially received over a portion of the outer diameter of the stem 112 and the lubricant fills the annular region between stem 112 and the bore 106.
At this point, those skilled in the art will appreciate that the tolerance of the inner layer 122 of the upper bushing 104 may be held tighter than if rubber or some other pliable material was used to form the inner layer 122, thereby allowing for a tighter clearance between the inner layer 122 of the bushing 104 and the outer diameter of the stem 112 and, accordingly, reducing rattle noise. Furthermore, those skilled in the art will appreciate that using an upper bushing 104 allows for a larger clearance between the outer diameter of the stem 112 and the second portion 130 of the bore 106, thereby allowing lubricating fluid to easily fill the annular region therebetween.
Still furthermore, those skilled in the art will appreciate that interference fits and high pin slide forces may be avoided by forming the inner layer 122 of the upper bushing 104 from a rigid, rather than pliable, material. Still furthermore, those skilled in the art will appreciate that the pliable outer layer 124 of the upper bushing 104 may create an interference fit between the bushing 104 and the bore 106, thereby holding the bushing 104 in place. However, those skilled in the art will appreciate that an adhesive may also be used to hold the bushing 104 in place. Still furthermore, those skilled in the art will appreciate that the pliable outer layer 124 of the upper bushing 104 may allow for movement of the pin 102 in the bore 106 while dampening any noise caused by the movement of the pin 102 in the bore 106. Still furthermore, those skilled in the art will appreciate that the pliable outer layer 124 may allow the rigid inner layer 122 to float and self align the pin 102 inside the bore 106 and may reduce the slide force of the assembly 100.
Referring to
Referring to
Those skilled in the are will appreciate that the tolerance of the inner layer 222 of the upper bushing 204 may be held tighter than if rubber or some other pliable material was used to form the inner layer 222, thereby allowing for a tighter clearance between the inner layer 222 of the bushing 204 and the outer diameter of the stem 212 and, accordingly, reducing rattle noise.
Furthermore, those skilled in the art will appreciate that the pliable material of the center radial layer 223 may allow for slight movement by undergoing a shear and/or compression, thereby dampening movement and reducing rattle noise.
Still furthermore, those skilled in the art will appreciate that the rigid outer radial layer 224 may provide the ability to press fit or knurl the upper bushing 204 into the larger diameter portion 228 of the bore 206.
Referring to
Like the upper bushing 204 of assembly 200, the upper bushing 304 may be a radially layered structure and may include a rigid inner radial layer 322, a pliable center radial layer 323 and a rigid outer radial layer 324. The rigid outer radial layer 324 may include a pin engaging portion 325 that may extend beyond the larger diameter portion 328 of the bore 306. The pin engaging portion 325 of the rigid outer radial layer 324 may include an attachment pin engaging structure 327, such as a flange, a bracket, a tenon or the like, adapted to be engaged by the attachment pin 350.
Accordingly, those skilled in the art will appreciate that providing a attachment pin engaging structure 327 on the upper bushing 304 may eliminate the need for forming (e.g., machining) such structures directly on the caliper body 308, thereby providing an opportunity for cost reduction.
Although various aspects of the disclosed brake caliper guide pin assembly have been shown and described, modifications may occur to those skilled in the art upon reading the specification. The present application includes such modifications and is limited only by the scope of the claims.
The present application claims priority from U.S. Provisional Ser. No. 60/852,764 filed on Oct. 19, 2006, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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60852764 | Oct 2006 | US |