Back to results
US 7,197,968 B2Granted
Screwdriver with adjustable device to limit transmitted torque
AssigneeFelo-Werkzeugfabrik Holland-Letz GmbH
InventorRainer Bubel
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeFelo-Werkzeugfabrik Holland-Letz GmbH
InventorRainer Bubel
Estimating the term…
A screwing tool with a device to adjust transmitted torque comprises a handle to introduce a torque to the device, which is borne in the hollow of the handle and a drive shaft as an output element of the torque. On the drive shaft inside the handle, two separate couplings are assembled, having between them a compression spring exerting a spring force against the two couplings. Each coupling comprises a first and a second socket engaging each other by gearings at their opposing faces. The maximum torque at which the torque transmission will be interrupted can be adjusted by an adjustment element wherein the distance between the couplings can be changed, thereby resulting in a change of the tension of the spring exerting a load on the couplings. The teeth of the gearings slide and the sockets rotate relatively to each other and interrupt the torque-transmission if a pre-adjusted torque is exceeded.
A screwing tool with an adjustable device to limit transmitted torque, said device comprising a handle with an axially extending hollow in which a mechanism is arranged to interrupt the transmission of torque from the handle to a drive shaft if a pre-adjusted torque value is exceeded, said mechanism comprising a drive shaft on which two couplings are assembled, each coupling comprising a first and second socket which are engaging each other by a gearing at their opposing side faces, both first sockets are engaging with an inner gearing with a gearing on the circumferential surface of the drive shaft and are moveable in a longitudinal direction, both second sockets are rotatively coupled and in mesh with the handle by means of a gearing, and a compression spring arranged with pre-tension between the two couplings, said hollow in the handle being shut by a cap.
Dependencies are inferred from the claim text.