Looper adjusting device of chain-type sewing machine

The invention discloses a looper adjusting device of a chain-type sewing machine. The height of a looper can be adjusted by the device to adapt to thread loops in different shapes. The device comprises a sewing machine needle, a looper shaft, the looper and an adjusting mechanism, the adjusting mechanism comprises an eccentric sleeve, the eccentric sleeve sleeves the looper shaft and can rotate relative to the looper shaft, and the looper is installed on the eccentric sleeve through a looper base; the distance between a large-external-diameter portion of the eccentric sleeve and the shaft axisof the looper shaft is longer than that between a small-external-diameter portion of the eccentric sleeve and the shaft axis of the looper shaft; in a first use state of the looper adjusting device,when the point of the looper is located over a needle hole, the large-external-diameter portion is located on the upper side of the looper shaft, and a first height difference is formed between the point of the looper and the