Patent ID: 6640674
Filing Date: 2003-11-04
Classification: B25B

Abstract:
In a screwdriver of the type having a variable torque-limiting in-line drive having a handle with a longitudinal axis and a forward end and a rearward end along said axis and a cavity extending along said axis between said ends for receiving an elongated drive bit disposable in said cavity at said forward end and extending from said handle for engaging an object to be rotationally driven by said screwdriver, two gears disposed in said cavity and having a common central axis co-axial with said longitudinal axis and said gears having teeth thereon in mesh between said gears on a plane transverse to said central axis and said gears being arranged for rotation of only one of said gears about said central axis in one direction of rotation and relative to the other of said gears when subjected to a limited torque, said bit being rotatably connectable to said other of said gears, and a torque spring in said cavity and being operative on said one gear for yieldingly urging said gears into mesh with each other to thereby limit the rotation torque transmitted between said two gears in said one direction, the improvement comprising:a first adjustable control disposed in said cavity at said rearward end of said handle and being rotationally threaded to said handle and threadedly operative on said torque spring in the direction along said central axis for applying axial force on said gears to establish the limit of rotation torque transmitted between said gears to said bit, a second adjustable control at said rearward end of said handle and rotationally mounted on said handle and being rotationally connectable with said first adjustable control and extending externally of said handle whereby said second adjustable control is accessible exteriorly of said handle and said adjustable controls are operationally associated with each other for threaded operation of said first adjustable control on said handle to establish the torque transmitting force between said gears, said second adjustable control being movable for selective releasable connection with said handle for selectively securing said controls against rotation on said handle, and a control spring operative on said second adjustable control to yieldingly urge said second adjustable control into releasable rotational relationship with said handle to establish the torque limit.