Tension indicator for fastener means
First Claim
1. A tension indicator for use with fastener means such as cooperating nut and bolt that are adapted to be applied to a workpiece, said tension indicator comprising a pair of washers adapted to be placed on the fastener means between a load applying surface thereof and the workpiece, each of said washers including opposing concave and convex surfaces, a central portion of each of said washers having a hole therethrough from said concave surface to said convex surface for receiving the fastener means, the concave surfaces of the pair of washers facing in opposite directions toward each other in an assembled condition, each of said washers further including at least one finger extending outwardly from said central portion, said one finger of each washer including an outermost end face disposed between opposing faces integrally extending from said concave and convex surfaces and between opposing sides thereof, said one finger of each washer being disposed in a side-by-side relationship to each other in said assembled condition with one of said sides of each finger being adjacent to each other, said end faces being inclined at different angles with respect to each other in said assembled condition without any load being applied to said washers, said end faces of said fingers being aligned side-by-side with each other only when a predetermined load has been applied to said washers and the fastening means, and retention means disposed on at least one of said washers for preventing relative rotation between said washers to maintain said side-by-side relationship of said fingers.
1 Assignment
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Accused Products
Abstract
A tension indicator for use with fasteners such as a cooperating nut and bolt. The tension indicator comprises a pair of washers for placing on the shank of the bolt between the bolthead or nut and the workpiece that is to be secured by the fastener. Each washer includes a concave central portion having a hole therethrough for receiving the shank of the bolt with the concave surfaces of the washers facing in opposite directions in the assembled condition. Each washer further includes at least one finger extending outwardly from the central portion. Prior to the application of the load on the tension indicator by either the fastener or the workpiece, the outermost end faces of the coacting fingers will be at equal and opposite angles with respect to each other. After a predetermined load has been applied to the fastener, the outermost end faces of the coacting fingers will be aligned with each other to thereby visually indicate that the desired load has been achieved. Preferably, each washer has a plurality of fingers, each washer including first and second spaced apart and diametrically opposed pairs of fingers as well as one pair of diametrically opposed single fingers that are interdigitated with the two pairs of spaced apart fingers in the assembled condition. In one embodiment, the desired load is achieved when the washers are fully compressed, while in a second embodiment the desired load is achieved before full compression of the washers is achieved. If desired, teeth may be formed on the central portion of each washer about the hole therethrough so that the washer acts as a lock washer.
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Citations
8 Claims
- 1. A tension indicator for use with fastener means such as cooperating nut and bolt that are adapted to be applied to a workpiece, said tension indicator comprising a pair of washers adapted to be placed on the fastener means between a load applying surface thereof and the workpiece, each of said washers including opposing concave and convex surfaces, a central portion of each of said washers having a hole therethrough from said concave surface to said convex surface for receiving the fastener means, the concave surfaces of the pair of washers facing in opposite directions toward each other in an assembled condition, each of said washers further including at least one finger extending outwardly from said central portion, said one finger of each washer including an outermost end face disposed between opposing faces integrally extending from said concave and convex surfaces and between opposing sides thereof, said one finger of each washer being disposed in a side-by-side relationship to each other in said assembled condition with one of said sides of each finger being adjacent to each other, said end faces being inclined at different angles with respect to each other in said assembled condition without any load being applied to said washers, said end faces of said fingers being aligned side-by-side with each other only when a predetermined load has been applied to said washers and the fastening means, and retention means disposed on at least one of said washers for preventing relative rotation between said washers to maintain said side-by-side relationship of said fingers.
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8. A tension indicator for use with fastener means such as cooperating nut and bolt that are adapted to be applied to a workpiece, said tension indicator comprising a pair of washers adapted to be placed on the fastener means between a load applying surface thereof and the workpiece, each of said washers including a concave, central portion having a hole therethrough for receiving the fastener means, the concave surfaces of the pair of washers facing in opposite directions toward each other in an assembled condition, each of said washers further including at least one finger extending outwardly from said central portion, said one finger of each washer being disposed adjacent to each other in said assembled condition, outermost end faces of said fingers being aligned with each other only when a predetermined load has been applied to said washers and the fastening means, each of said washers including first and second diametrically opposed pairs of spaced apart fingers and one pair of diametrically opposed single fingers that are interdigitated with said two pairs of spaced apart fingers in the assembled condition.
Specification