Disc brake pad assembly proof-testing
AssigneeCooper Industries, Inc.
InventorsChristopher James Hurtubise, Winston Randolph Mason, Jr., James William Powe
Life of this patent
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Abstract
A method and apparatus for non-destructively proof-testing the integrity of the bond between an integrally-molded disc brake pad assembly metallic backing plate element and its adhered molded friction material pad element advantageously tests the bond by tensile stressing rather than by conventional shear stressing.
Claims5
In a method of proof testing the bond integrity of an integrally-molded disc brake pad assembly having a metallic backing plate element provided with at least one interior extrusion opening and having a molded friction material pad element bonded to said backing plate element and extruded into the backing plate element extrusion opening, the steps of:
- restraining said assembly metallic backing plate element against movement along a first direction;
- positioning a rigid proof-load pin test element in non-adhered contact with said molded friction material pad element at said backing plate element extrusion opening;
- applying a compressive force to said rigid proof-load pin test element and to said molded friction material pad element at said metallic backing plate element interior extrusion opening in a direction substantially parallel to said first direction;
- and
- removing said rigid proof-load pin test element from contacting relation with said molded friction material pad element,
- said applied compressive force subjecting portions of the bond of said molded friction material pad element to said metallic backing plate in areas adjacent said metallic backing plate element extrusion opening to potential failure by tensile stressing without separating portions of said molded friction material pad element from said metallic backing plate element.
In test apparatus for use in proof-testing a disc brake pad assembly having a metallic backing plate element provided with at least one interior extrusion opening and having an integrally-molded friction material pad element bonded to said metallic backing plate element and extruded into said metallic backing plate element interior extrusion opening, in combination:
- base means supporting said metallic backing plate element against movement in a downward direction and receiving said integrally-molded friction material pad element in an internal cavity;
- a vertically movable hold-down bar element having an interior proof-load pin element vertically aligned with said metallic backing plate element interior extrusion opening;
- and
- compression spring means co-operating with said hold-down bar proof-load pin element and variably pressing said proof-load pin element into direct contact with said integrally-molded friction material pad element when said hold-down bar element is brought into engagement with said metallic backing plate element,
- said compression spring means simultaneously placing the integral bond between said molded friction material pad element and said metallic backing plate element in tension in regions surrounding said metallic backing plate element extrusion opening when said hold-down bar element contacts said metallic backing plate element in clamping relation to said base means and compresses said compression spring means.
Dependencies are inferred from the claim text.