An overlock sewing machine includes: a looper cover detection member movable from non-switching to switching positions with looper cover open to closed state transition, with switching member operation switching the threading mechanism state to sewing-enabled after looper cover detection member movement to switching position; a side cover detection member movable from non-detection to detection positions with side cover open to closed state transition; and a lever coupled to the looper cover detection member and side cover detection member, switchable between states of pressing and not pressing the operating protrusion, following looper cover detection member and side cover detection member operating states. The lever is set to the pressing state upon movement of the looper cover detection member to switching position and of the side cover detection member to detection position.

An overlock sewing machine includes: a looper cover detection member movable from non-switching to switching positions with looper cover open to closed state transition, with switching member operation switching the threading mechanism state to sewing-enabled after looper cover detection member movement to switching position; a side cover detection member movable from non-detection to detection positions with side cover open to closed state transition; and a lever coupled to the looper cover detection member and side cover detection member, switchable between states of pressing and not pressing the operating protrusion, following looper cover detection member and side cover detection member operating states. The lever is set to the pressing state upon movement of the looper cover detection member to switching position and of the side cover detection member to detection position.

With a overlock sewing machine, when a switching mechanism is switched to a threading-enabled state, and a looper cover is closed, the looper cover is slid toward one side in the hinge shaft axial direction so as to operate a detection lever. In the non-operating state, the detection lever is set to an initial position where it does not press an operation protrusion of a switch. When a side cover is closed, and the detection lever is operated, the operation lever is set to an operation-enabled position where it presses the operation protrusion. When the operation lever is operated, and the side cover is opened, the detection lever is set by passing through the operation-enabled to the operation-disabled position where it does not press the operation protrusion.

With a overlock sewing machine, when a switching mechanism is switched to a threading-enabled state, and a looper cover is closed, the looper cover is slid toward one side in the hinge shaft axial direction so as to operate a detection lever. In the non-operating state, the detection lever is set to an initial position where it does not press an operation protrusion of a switch. When a side cover is closed, and the detection lever is operated, the operation lever is set to an operation-enabled position where it presses the operation protrusion. When the operation lever is operated, and the side cover is opened, the detection lever is set by passing through the operation-enabled to the operation-disabled position where it does not press the operation protrusion.

An overlock sewing machine includes: a looper cover detection member movable from non-switching to switching positions with looper cover open to closed state transition, with switching member operation switching the threading mechanism state to sewing-enabled after looper cover detection member movement to switching position; a side cover detection member movable from non-detection to detection positions with side cover open to closed state transition; and a lever coupled to the looper cover detection member and side cover detection member, switchable between states of pressing and not pressing the operating protrusion, following looper cover detection member and side cover detection member operating states. The lever is set to the pressing state upon movement of the looper cover detection member to switching position and of the side cover detection member to detection position.

An overlock sewing machine includes: a looper cover detection member movable from non-switching to switching positions with looper cover open to closed state transition, with switching member operation switching the threading mechanism state to sewing-enabled after looper cover detection member movement to switching position; a side cover detection member movable from non-detection to detection positions with side cover open to closed state transition; and a lever coupled to the looper cover detection member and side cover detection member, switchable between states of pressing and not pressing the operating protrusion, following looper cover detection member and side cover detection member operating states. The lever is set to the pressing state upon movement of the looper cover detection member to switching position and of the side cover detection member to detection position.

With a overlock sewing machine, when a switching mechanism is switched to a threading-enabled state, and a looper cover is closed, the looper cover is slid toward one side in the hinge shaft axial direction so as to operate a detection lever. In the non-operating state, the detection lever is set to an initial position where it does not press an operation protrusion of a switch. When a side cover is closed, and the detection lever is operated, the operation lever is set to an operation-enabled position where it presses the operation protrusion. When the operation lever is operated, and the side cover is opened, the detection lever is set by passing through the operation-enabled to the operation-disabled position where it does not press the operation protrusion.

With a overlock sewing machine, when a switching mechanism is switched to a threading-enabled state, and a looper cover is closed, the looper cover is slid toward one side in the hinge shaft axial direction so as to operate a detection lever. In the non-operating state, the detection lever is set to an initial position where it does not press an operation protrusion of a switch. When a side cover is closed, and the detection lever is operated, the operation lever is set to an operation-enabled position where it presses the operation protrusion. When the operation lever is operated, and the side cover is opened, the detection lever is set by passing through the operation-enabled to the operation-disabled position where it does not press the operation protrusion.