Patent ID: 9695536
Date: 2017-07-04
CPC Classifications: D05B

Claim:
1. An overlock sewing machine comprising: a swing lever portion arranged such that the swing lever portion can be swung in a predetermined range such that the swing lever is set to an enable position in a stationary state when rotation of a main shaft is to be enabled, and such that the swing lever is swung and shifted to a position away from the enable position when the rotation of the main shaft is to be disabled; a switch that switches a motor configured to drive the main shaft between a driving enable state and a driving disable state; a detection lever arranged such that the detection lever can be swung with a swinging axis that extends in a direction that differs from the direction in which a swinging axis of the swing lever portion extends, and configured to be swung between an operation enable position at which the switch is set to the motor driving enable state and an operation disable position at which the switch is set to the motor driving disable state, wherein the swinging axis of the detection lever is configured at a skew position with respect to the swing axis of the swing lever portion; a detection lever spring that applies a force to the detection lever toward the operation disable position; a cover detection shaft arranged such that it extends along a direction in which the swinging axis of the swing lever portion extends, and configured such that it can be shifted to a position so as to press and shift the detection lever from the operation disable position to the operation enable position; a cover detection shaft spring that applies a force to the cover detection shaft so as to increase a distance between the cover detection shaft and the detection lever; a looper cover arranged so as to cover at least a part of the looper, and configured to be opened and closed; a pressing portion configured to be shifted together with the looper cover as a single unit, and to press the cover detection shaft such that the cover detection shaft approaches the detection lever when the looper cover is set to a closed position; a looper cover spring that applies a force to the looper cover such that, when the looper cover is set to a closed state, the cover detection shaft is shifted against the force applied by the cover detection shaft spring and the force applied by the detection lever spring so as to shift the detection lever from the operation disable position to the operation enable position; and an operation limiting portion that limits an operation of the detection lever according to the position of the swing lever portion such that, when the swing lever portion is set to the enable position, the detection lever can be swung and shifted to the operation enable position, and such that, when the swing lever portion is not set to the enable position, the detection lever cannot be swung and shifted to the operation enable position.