Impact wrench having torque controlling faculty

Details Impact wrench having torque controlling faculty Impact wrench having torque controlling faculty

1992-03-09

1993-01-26

Watts, Douglas D.

Tool driving or impacting

Automatic control of power operated means

Drive means responsive to torque or speed condition

173181, 81470, B25B 2314

Patent

active

051815753

ABSTRACT:
An impact wrench with a torque controlling faculty including an air motor for generating a primary torque, an oil pressure pulse generating unit for converting the primary torque into a pulsatory secondary torque, a main spindle to which the pulsatory secondary torque is applied, a transducer for detecting the pulsatory secondary torque and a shut-off valve which is closed to stop a supply of a compressed air to the air motor when the secondary torque exceeds a predetermined threshold value. The main spindle is made of material having the magnetic strictive effect and the distortion of the main spindle is detected by a pair of coils arranged in opposition to the main spindle. The coils are connected into a bridge circuit together with resistors and an exciting current having a sinusoidal waveform is supplied to a first set of diagonal points of the bridge circuit. A voltage appearing across a second set of diagonal points is detected to produce a torque detection signal which represents the pulsatory secondary torque. Then the torque detection signal is sampled and held at a predetermined phase which is fixedly related to a phase of the exciting current to produce a torque measurement signal which represents a peak value of the pulsatory secondary torque applied to the main spindle.

REFERENCES:
patent: 3572447 (1971-03-01), Pauley et al.
patent: 3710874 (1973-01-01), Seccombe et al.
patent: 3926264 (1975-12-01), Bardwell et al.
patent: 3975954 (1976-08-01), Barnich
patent: 4142591 (1979-03-01), Himmelstein
patent: 4281538 (1981-08-01), Dudek
patent: 4418765 (1983-12-01), Mari et al.
patent: 4648282 (1987-03-01), Alender et al.

Affiliated with

Also associated with

Rating

Impact wrench having torque controlling faculty does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Impact wrench having torque controlling faculty, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Impact wrench having torque controlling faculty will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1408136