Patent ID: 6725746
Filing Date: 2004-04-27
Classification: B25B,F16B

Abstract:
An asymmetrical high torque wrenching system comprising: a fastener having a central axis comprising, a plurality of fastener tightening surfaces formed in a periphery of the fastener and spaced around said central axis of said fastener, wherein each of said plurality of fastener tightening surfaces forms a fastener tightening angle between a first vector and each fastener tightening surface, said first vector extending radially from said central axis of said fastener through a center point of each fastener tightening surface, and a plurality of fastener loosening surfaces formed in the periphery of the fastener and spaced around said central axis of said fastener, and being equal in number to the number of fastener tightening surfaces, wherein each of said fastener loosening surfaces forms a fastener loosening angle between a second vector and each fastener loosening surface, said second vector extending radially from said central axis of said fastener through a center point of each fastener loosening surface, each one of said fastener loosening surfaces being transverse to one of said fastener tightening surfaces to form at least one fastener protuberance and an equal number of fastener recesses, wherein the fastener tightening angle is smaller than the fastener loosening angle; anda wrench provided for mating with and driving the fastener with a higher torque in a tightening direction than in a loosening direction, said wrench having a central axis and comprising, a plurality of wrench tightening surfaces formed in a periphery of the wrench and spaced around said central axis of said wrench, wherein each of said wrench tightening surfaces forms a wrench tightening angle between a third vector and each wrench tightening surface, said third vector extending radially from said central axis of said wrench through a center point of each wrench tightening surface, and a plurality of wrench loosening surfaces formed in the periphery of the wrench and spaced around said central axis of said wrench and being equal in number to the number of wrench tightening surfaces, wherein each of said wrench loosening surfaces forms a loosening angle between a fourth vector and each wrench loosening surface, said fourth vector extending from said central axis of said wrench through a center point of each wrench loosening surface; each one of said wrench tightening surfaces being transverse to one of said wrench loosening surfaces to form at least one wrench protuberance and being transverse to another one of said wrench tightening surfaces to form at least one wrench recess, the number of wrench protuberances being equal to the number of wrench recesses, wherein the wrench tightening angle is smaller than the wrench loosening angle for each of the wrench loosening surfaces and wrench tightening surfaces; wherein at least one of the plurality of wrench tightening surfaces formed is configured to mate with at least one of the plurality of fastener tightening surfaces in order to rotate the fastener to a tightened position, and at least one of the plurality of wrench loosening surfaces is configured to mate with at least one of the plurality of fastener loosening surfaces in order to rotate the fastener to a loosened position; and wherein each of said wrench and fastener recesses include a joining surface that connects the respective loosening surface and corresponding transverse tightening surface.