Sewing machine gripper extraction device includes S-shaped connecting mechanism between gripper drive arm and sewing pulley drive shaft, which can be pivoted between two positions

摘要

The device includes an S-shaped connecting mechanism between the gripper drive arm (5) fastened to the gripper drive shaft (3), and a rotational axis parallel to this shaft, fixed in the sewing machine bed and working with the sewing pulley. The connecting mechanism ends, pivot on a peg between a first position with connection in a straight line, the gripper (1a-c) held within a given region of pivoting, and a second position with the connections in a curved form, allowing the gripper to be removed from the region of swinging. A resilient holder biases the S-mechanism into the first position. A further mechanism allows the S-mechanism to be switched over from the first position to the second, against the spring resilience of the holder. A gripper return unit allows it to be switched back to the first position, with rotational axis of the belt pulley turned. Preferred features: A cover (28) on a front side wall of the sewing bed (25) can be opened and closed freely, permitting the gripper to be extracted to the front. The holder includes a leaf spring (14), one end joined to a surface of one connection, the other sprung into contact against a surface of the other connection. The gripper is reset by a projecting section, when the axis is turned through a given angle in one direction by turning the sewing belt pulley. The projection extends from a location near a pivoting connecting point on the S-mechanism. It is brought into contact with the circumferential surface of the gripper drive arm. The S-mechanism is switched over from a second position to a first, contact between the projection and gripper drive arm being maintained with a further rotation of the axis in the same direction. A moveable section pulls up the gripper and can be brought into contact with the projection or moved away. This extends from a connection of the S-mechanism. It is subject to resilient force in the direction of removal. A control lever acts against resilience of the moving section in the direction of contact with the projection. The moving section is introduced and held in a cylindrical support attached on a lower part of the upper wall surface of the sewing bed, near the stitching plate. The control lever has a large lever arm ratio. The control lever has a notch assisting locking in an out-of-use position.