Torque-transmitting tool
AssigneeWera Werk Hermann Werner GmbH & Co.
InventorsMartin Strauch, Robert Hoy
Life of this patent
Estimating the term…
Abstract
A tool, particularly a torque-transmitting tool, such as a screwdriver or a screwdriver bit, having a shaft and a working region. In order advantageously to take up peak torques with such a tool, a damping region of lower hardness or lower torsion-bar constant than the working region is provided, associated with the shaft. For this purpose, the damping region can be subsequently annealed or have a different composition of material. The latter is preferably provided in the case of a tool of sintered metal.
Claims12
A torque-transmitting tool, comprising a shaft having a first end and a second end, and a working region supported by the shaft at one of said shaft ends, wherein the shaft has at least one shaft section between said first end and said second end of lower hardness than the working region;
- and
- wherein said hardness of said one shaft section varies continuously from maximum values at both of said ends to a minimum value in a central region of said one shaft section, thereby attaining a reduced torsion spring constant;
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- said one shaft section comprises a material, at least part of the material being an annealed material, a remainder of the material of the one shaft section extending with uniformity of material into the working region, a hardness of the annealed material being less than a hardness of said remainder of the material.
A torque-transmitting tool, comprising a shaft having a first end and a second end, and a working supported by the shaft at one of said shaft ends, wherein the shaft has at least one shaft section between said first and said second end of lower hardness than the working region;
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- wherein said hardness of said one shaft section varies continuously from maximum values at both of said ends to minimum value in a central region of said one shaft section, thereby attaining a reduced torsion spring constant;
- and
- said working region comprises a first sintered material and said one shaft section comprises a second sintered material different from said first sintered material, the tool further comprising a drive region comprising a material harder than the second sintered material of the one shaft section, the first sintered material of said working region being harder and having a higher modulus of elasticity than the second sintered material of the one shaft section.
Dependencies are inferred from the claim text.