Method of and apparatus for controlling nut runner
Patent 4908926 Issued on March 20, 1990. Estimated Expiration Date: 
December 22, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 22, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2720803 3827506 Multi-stage tightening system Method for tightening bolts Microprocessor control yield point tightening system Apparatus and method for determining torque, presenting digital torque readout and automatic cycling and termination of wrench operation in a torque wrench system Patent #: 4791838 InventorsAssigneeApplicationNo. 288248 filed on 12/22/1988US Classes:29/407.02, Torquing threaded assemblage or determining torque herein29/446, With prestressing of part81/469, Means for regulating motor173/181Having torque sensorExaminersPrimary: Gorski, Joseph M.Foreign Patent References
International ClassB23Q 017/00Foreign Application Priority Data1987-12-23 JPAbstractThe output shaft of a nut runner for tightening a fastener such as a bolt is first rotated with a first torque at a first speed. When the tightening torque of the output shaft reaches a preset switching torque, the first torque first speed rotation of the output shaft is interrupted, and thereafter the output shaft is rotated with a second torque at a second speed. When the tightening torque then reaches a preset snug torque, the second torque second speed rotation of the output shaft is interrupted, and thereafter the output shaft is rotated with a third torque at a third speed. When the tightening torque reaches a preset final torque, the third torque third speed rotation of the output shaft is stopped, thus completing the tightening of the fastener. | |
