弯针尖与左机针的位置:当机针上升 弯针向左运动到左机针中心线时,
在左机针的针孔上1-1.5mm。左机针与弯针的间隙应为0.05mm。
The position of looper and needle: when the needle moves up, the looper
moves left to the left needle central position, and 1-1.15mm above the
needle hole. Meanwhile, the gap of left needle and looper is 0.05mm
图9(Figure9)