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US 5,277,261 AGranted
Tightening tool
AssigneeMakita Corporation
InventorMasahiko Sakoh
Life of this patent
Estimating the term…
Abstract
A tightening tool includes a hammer for impacting on an anvil which drives a nut etc. A microphone is provided for converting impact sounds of the hammer on the anvil into an electric signal. A counting device counts the number of pulses of the electric signal. A setting device is provided for setting a set number of impacts to be obtained. A switch device compares the counted number of pulses with the set number and stops a motor for driving the hammer when the number of pulses coincides with the set number.
Claims5
A tightening tool, comprising:
- a hammer rotatably driven by drive means;
- an anvil driven by said hammer in such a manner that said hammer is rotated idly when the torque transmitted from said hammer to said anvil exceeds a predetermined value and that said hammer impacts on said anvil so as to rotate said anvil when said hammer is rotated by a predetermined angle after said hammer has been rotated idly;
- a microphone for converting impact sounds of said hammer on said anvil into an electric signal;
- counting means for counting the number of pulses of said electric signal which corresponds to the number of impact;
- setting means for setting a set number of impact to be obtained;
- and
- switch means for comparing the number of pulses counted by said counting means with said set number set by said setting means and for stopping said drive means when the number of pulses coincides with said set number.
4 more elements
Dependencies are inferred from the claim text.