| 摘要 |
773,735. Sewing machine bobbins. PHILIPS, J. M. July 12, 1955, No. 20085/55. Class 112. A bobbin is wound on a spindle of approximately 1/32 inch diameter and after removal from the spindle is subjected to pressure of approximately 1000 lbs. at a temperature of 300 to 400 degrees F. to form a cylindrical bobbin 10 with flat ends which will retain its form. A radial groove 10a is formed in one end face in the press and the central axially projecting thread 11 lies in this groove. |
