Patent ID: 6543316
Filing Date: 2003-04-08
Classification: B25B

Abstract:
A ratchet wrench for selectively applying torque to fasteners, said ratchet wrench comprising:a wrench body comprising (a) an elongated manually engageable handle configured for manual grasping thereof and (b) a ratchet head provided on said handle, said wrench body providing spaced apart first and second engaging member abutment surfaces; a torque receiving gear mounted for rotation about a gear axis relative to said ratchet head, said torque receiving gear providing a plurality of gear teeth provided about said gear axis in a circular arrangement; said torque receiving gear being constructed and arranged to be removably coupled to a rotatable fastener in torque transmitting relation such that torque applied to said torque receiving gear is transmitted to the fastener removably coupled therewith to affect rotation of the fastener; a switch member mounted externally to said wrench body to be accessible from an exterior of said wrench body, said switch member being selectively movable between a first switch position and a second switch position; a gear engaging member having a set of engaging teeth provided in an arcuate and concave arrangement substantially complementary to the circular arrangement of said gear teeth, said engaging teeth being configured to be engaged with said gear teeth in intermeshed relation. a mounting element mounting said gear engaging member to said switch element, said gear engaging member being pivotally mounted to said mounting element such that selective movement of said switch member into said first position thereof moves said gear engaging member into a first ratcheting position and selective movement of said switch member into said second position thereof moves said gear engaging member into a second ratcheting position angularly spaced from said first ratcheting position with respect to said gear axis, said pivotal mounting of said gear engaging member enabling said gear engaging member to pivot relative to said mounting element as said gear engaging member moves between said first and second ratcheting positions thereof; said gear engaging member being constructed and arranged such that, when said torque receiving gear is removably coupled to a rotatable fastener in torque transmitting relation as aforesaid and said gear engaging member is in said first ratcheting position thereof, a force applied to said handle to affect a first torque applying movement abuts said gear engaging member against said first abutment surface to forceably engage the engaging teeth of said gear engaging member with the gear teeth of said torque receiving gear in intermeshed relation to prevent rotation of said wrench body relative to said torque receiving gear so that the force applied to said handle to affect the first torque applying movement is transmitted through said gear engaging member and applied to said gear as a torque which is transmitted to the fastener to affect rotation thereof via the torque transmitting relation between said gear and the fastener; said gear engaging member being constructed and arranged such that, when said torque receiving gear is removably coupled to a rotatable fastener in torque transmitting relation as aforesaid and said gear engaging member is in said second ratcheting position thereof, a force applied to said handle to affect a second torque applying movement abuts said gear engaging member against said second abutment surface to forceably engage the engaging teeth of said gear engaging member with the gear teeth of said torque receiving gear to prevent rotation of said wrench body relative to said torque receiving gear so that the force applied to said handle to affect the second torque applying movement is transmitted through said gear engaging member and applied to said gear as a torque which is transmitted to the fastener to affect rotation thereof via the torque transmitting relation between said ratchet gear and the fastener; a spring engaged between said switch member and said mounting element so as to apply a biasing force to said gear engaging member through said mounting element, wherein said switch member has a bore formed therein and wherein said gear engaging member has a bore formed therein, said mounting element being L-shaped having a first leg received in the bore of said switch member and a second leg received in the bore of said gear engaging member, said spring being positioned between said mounting element and said switch member such that, (a) when said gear engaging member is in said first ratcheting position, said spring is disposed in a first spring biasing position so that at least a component of the biasing force is directed circumferentially with respect to said gear axis and (b) when said gear engaging member is in said second ratcheting position, said spring is disposed in a second spring biasing position so that at least a component of the biasing force is directed circumferentially with respect to said gear axis; said gear engaging member and said spring being constructed and arranged such that, when said torque receiving gear is removably coupled to a rotatable fastener in torque transmitting relation as aforesaid and said gear engaging member is in said first ratcheting position thereof, a force applied to said handle to affect a movement opposite the first torque applying movement rotates said wrench body relative to said torque receiving gear so that (a) said first abutment surface moves to a position wherein it allows said gear engaging member to move radially outward with respect to said rotational axis to permit said engaging teeth to disengage from said gear teeth, and (b) said engaging member moves generally circumferentially with respect to said gear axis with the engaging teeth thereof ratcheting over said gear teeth; said gear engaging member and said spring being constructed and arranged such that, when said torque receiving gear is removably coupled to a rotatable fastener in torque transmitting relation as aforesaid and said gear engaging member is in said second ratcheting position thereof, a force applied to said handle to affect a movement opposite the second torque applying movement rotates said wrench body relative to said torque receiving gear so that (a) said second abutment surface moves to a position wherein it allows said gear engaging member to move radially outward with respect to said rotational axis to permit said engaging teeth to disengage from said gear teeth, and (b) said engaging member moves generally circumferentially with respect to said gear axis with the engaging teeth thereof ratcheting over said gear teeth.