Pressure detecting device for torque control wrench

Abstract

Abstract A pressure detecting device in a torque control wrench has a rotor to be rotated by high pressure air, an output shaft and a device for generating impulse torque with the use of oil pressure on the output shaft due to rotation of the rotor. The device has a liner rotated by the rotor rotatably mounted on the output shaft. The device forms a high pressure chamber and a low pressure chamber in the liner for the generation of impulses on the output shaft, and has a hole therein having first and second ports communicating with the high and low pressure chambers, respectively. A valve is disposed in the hole for adjustably regulating the flow of oil from the first port to the second port and for generating a shut-off signal. The valve has a valve shaft adjustably mounted in the hole, having a passage therein communicating with the high pressure chamber. The passage has an opening at an end of the valve shaft. A relief valve is biased by a spring to close the opening of the passage and open upon the high pressure chamber reaching a set pressure. The liner has an end lid with a cylinder and a shut-off signal passage communicating the cylinder with the relief valve. A rod extends through the rotor and has a piston at an end thereof disposed in the cylinder, the opposite end of said rod being provided with a shut-off valve mechanism.

Inventors

• 👤 Koji Tatsuno

Bibliographic Details