US 4,063,474 AGranted

Torque limiting screwdriver

AssigneeDresser Industries, Inc.

InventorNorman Conrad Klopping

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Abstract

The improved torque limiting screwdriver described hereinafter includes an elongated bit receptacle that extends into a handle or gripping portion. An operative connection is made between the handle and the bit receptacle by a torque limiting device that can be adjusted to release at predetermined torque settings. The end of the gripping portion opposite to that from which the bit receptacle extends is provided with a cap member that is interconnected with means for adjusting the torque setting. The cap member provides an extension of the gripping portion and presents a smooth end to the user to avoid discomfort during the use of the screwdriver. A threaded fastener extends through the cap member into the gripping portion so that the preset torque can be locked into the torque limiting screwdriver and, thus, avoid the possibility of an inadvertent change of the desired torque setting.

Claims4

Dependent claims

In an improved torque limiting screwdriver including a bit receptacle extending from one end of a generally cylindrical gripping means and rotatably adjustable torque limiting means operably connecting the bit receptacle with the gripping means, and the gripping means includes a plurality of radially spaced holes extending generally parallel to the bit receptacle, the improvement comprising a cap member arranged to be located at the other end of the gripping means and having:

an exterior wall portion generally conforming to the gripping means;
an exterior end portion providing an essentially smooth surface;
a surface portion smoothly connecting said wall and end portions;
a connection portion located interiorly of said wall portion connected for rotation with the torque limiting means, whereby rotation of said cap member relatively to the gripping means adjusts the torque limit of said screwdriver while said cap member prevents discomfort to the user of said screwdriver when force is applied thereto;
a hole through said end portion aligned with the holes in the gripping means;
and
releasable fastening means located in the hole in said cap member and arranged to be located in one of the holes in the gripping member to prevent inadvertent rotation of the cap member relative to the gripping means and releasable therefrom to permit relative rotation therebetween to adjust the torque limit.

4 more elements

Dependencies are inferred from the claim text.