标准号:IS 12109-1987
发布日期:1988/4/1 12:00:00
实施日期:1999/12/31 12:00:00
适用范围:Covers the general requirements of L 12* type light duty industrial sewing machine heads with maximum speed of 1 800 stitches per minute and mainly used for light fabric stitching. The main feature being rotary hook for lower thread which operates in a full rotary motion in a vertical plane on a horizontal axis, link-type, thread take-up and positive transmission from arm shaft to rotary hook shaft.