The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1991
Filed:
Jan. 09, 1990
Daniel M Elligson, Millers, MD (US);
Black & Decker Inc., Newark, DE (US);
Abstract
In an electrically powered combination screwdriver/drill opposing halves of a ratchet type torque tranmsitting clutch are normally biased axially apart by a compression spring. The output half of the clutch is fixed on the output spindle of the tool which is free to move axially within limits. For screwdriving operation, operator bias of the tool against the workpiece overcomes the spring, retracting the output spindle and bringing the clutch halves into engagement. An adjustable stop in the nose of the tool limits axially rearward movement of the output spindle and hence depth of engagement of the clutch teeth, thus providing a variable limit on torque transmitted. For the drilling mode, the rearward half of the clutch is cammed forward so that the clutch is firmly engaged for continuous rotation of the output spindle without specific torque limitation. An operator may switch from drilling mode to screwdriving mode and back without disturbing the torque limit adjustment of the screwdriving mode.