One-step buttonholer with hall effect sensor

In a zigzag sewing machine having stitch forming instrumentalitites including a reversible incremental feed mechanism and a reciprocatory needle bar arranged for lateral jogging motion, electro-magnetic actuation means for controlling various of the stitch forming instrumentalities and electronic logic circuitry for the activation of said actuation means and for the storing of various stitch patterns inclusive of a buttonhole pattern, means for determining the size of a buttonhole being sewn comprising:

• a downwardly biased presser bar;
• a buttonhole gauging presser foot pivotally mounted to the end of said presser bar, said presser foot including a shoe shiftably mounted thereto for movement in the direction of material feed;
• and
• magnetic indicating means cooperating with said presser foot for indicating to said electronic logic circuitry the size of the desired buttonhole.