JPS6057367U - Sewing machine thread detection device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

Figure 1 is a partial front view of the sewing machine, Figure 2 is a perspective view of the thread tension device of the present invention, Figure 3 is an explanatory diagram of the main parts, Figure 4 is an electric circuit diagram, and Figure 5 is a time chart. be.

Claims (1)

[Scope of Claim for Utility Model Registration] A position detection circuit A that detects the predetermined rotation angle position of the main shaft of a sewing machine and generates a position signal, and a circuit that always supplies a constant current and is insulated from the machine frame and fixed by forming a sliding surface. With the arranged sensing body 13, it always has an elastic force in one direction toward the sensing body, engages with the suture between the suture supply source and the suture part, and slides on the sliding surface of the sensing body in the latter half of the movement due to the elastic force. The thread take-up spring 3 has electrical conductivity and is capable of reciprocating in the direction crossing the sliding surface in relation to the increase/decrease in tension of the sewing thread during sewing. A sewing thread detection device for a sewing machine, comprising a detection circuit that generates a signal, and a gate circuit G2 that generates an abnormal signal in relation to the fact that a thread signal is not generated while a plurality of position signals are generated.