초록 ▼

A spin-welding apparatus utilizing a servo motor assembly has a closed-loop control circuit for rotating one part of the workpiece being welded relative to the other. In use, the servo motor immediately rotates the first part up to a set speed at which welding will occur, and a power cylinder moves

A spin-welding apparatus utilizing a servo motor assembly has a closed-loop control circuit for rotating one part of the workpiece being welded relative to the other. In use, the servo motor immediately rotates the first part up to a set speed at which welding will occur, and a power cylinder moves the first part into frictional contact with the second part. Contact between the two parts is observed by a microprocessor interrogating a signal from the servo output corresponding to an increase in the load on the servo motor due to frictional drag between the parts, with "contact" being identified as surpassing a predetermined threshold error or variance value between the closed-loop system's input and output values. The microprocessor then counts a predetermined number of revolutions, and terminates rotation of the servo motor and first part. For accurate radial alignment between the parts, rotation may continue past the predetermined number of revolutions that fraction of a revolution necessary to achieve proper alignment or orientation.

대표청구항 ▼

[ What is claimed is:] [12.] A method of spin-welding a first part to a second part, said method utilizing a drive mechanism having a closed-loop control system, a part holder coupled thereto for engagingly securing said first part, and a sensor for measuring an output from said drive mechanism, sai

[ What is claimed is:] [12.] A method of spin-welding a first part to a second part, said method utilizing a drive mechanism having a closed-loop control system, a part holder coupled thereto for engagingly securing said first part, and a sensor for measuring an output from said drive mechanism, said sensor producing an output signal which is fed back to a controller in said closed loop control system, said method comprising the steps of:providing the drive mechanism having the closed-loop control system, the part holder coupled, and the sensor for measuring the output from the drive mechanism;mounting the first part on the part holder coupled to the drive mechanism;actuating the drive mechanism to rotate the first part at a predetermined set speed;moving the first part into close confronting contact with the second part;observing frictional contact between the first part and the second part, said frictional contact being determined by measuring a predetermined variation in the load on the drive mechanism; andcounting a predetermined number of revolutions of the drive mechanism after frictional contact is observed, said predetermined number being sufficient for the frictional contact between the first part and the second part to produce a weld therebetween, such that rotation of the drive mechanism and the first part ceases upon the completion of said predetermined number of revolutions.