Looper threading device of circular sewing machine

Abstract

The present invention performs well threading against a looper. It is provided with: the looper side thread guide path (10, 20), which guides the looper thread to the thread extraction hole at the front end of the looper (1, 2); the device side thread guide path (30, 40), which has the looper thread The wire inlet (311, 411) where the loop wire is inserted; the positive pressure air supply part (50), which sends positive pressure air into the middle of the side wire guide path of the device; and the connection part (60), which guides the side wire of the looper The path is connected to the wire guide path on the device side, and at the boundary between the wire guide path on the looper side and the wire guide path on the device side, or on the side of the thread extraction hole compared to the boundary portion, a part of the positive-pressure air is provided to the wire guide on the looper side. A release port (122, 222) for external release of the guide path.

Description

technical field [0001] The invention relates to a looper threading device of a circular sewing machine. Background technique [0002] A conventional circular sewing machine is equipped with a threading device that guides the looping thread to the thread outlet of the looper through air. [0003] The threading device is provided with: a looper side thread guide path, which guides the looper thread to the thread extraction hole at the front end of the looper; a pump, which generates positive pressure air; and a device side thread guide path, which has a thread into which the looper thread is inserted. an introduction port; and a connecting pipe that connects the looper side wire guide path and the device side wire guide path by advancing and retreating (for example, refer to Patent Document 1). [0004] In this threading device, the positive pressure air from the pump is sent into the device-side thread guide path through a path that merges from the middle of the device-side ...

AI Technical Summary

Problems solved by technology

[0007] However, in the above-mentioned conventional threading device, since the thread guide path on the looper side is connected to the thread extraction hole of the small-diameter looper, the flow resistance becomes large on the side of the thread guide path on the looper side.

[0008] Therefore, if the looper side thread guide path and the device side thread guide path are connected by a connecting pipe, the air that has not completely flowed into the looper side thread guide path flows back to the thread inlet side, and the looper thread may be squeezed out, making it impossible to move the looper thread. Thread extraction hole leading to looper

Images