Patent 4506612 Issued on March 26, 1985. Estimated Expiration Date: August 13, 2002. 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.
A testing device for an automatic sewing machine wherein a succession of stitches are formed through variation in relative position between a needle and a work holder according to a batch of positional data stored in a memory. The device comprises a control circuit for controlling to operate stepper motors to effect variation in the relative position without reciprocating movements of the needle. The control circuit includes first control means for varying the relative position every time the positional data for each of the stitches is executed, second control means for varying the relative position every time the positional data for a plural number of the stitches are continuous executed at one time, and a selector for selectively actuating one of the first and second control means to select one of two modes in which the stored positional data are tested for verification.