A sewing machine includes a thread cutter. The thread cutter includes a cutter blade having a blade edge configured to cut a thread, and a movable member. The movable member includes a guide having a guide surface adjacent to the cutter blade. The guide is configured to receive force from the thread at the guide surface during the course of cutting the thread with the cutter blade and to move in a moving direction which is a longitudinal direction of the blade edge.

A sewing machine includes a needle plate, a bed portion, a first urging member, a first engagement member, a second engagement member, and a lock release mechanism. The bed portion is configured to support the needle plate. The first urging member is provided inside the bed portion and configured to urge the needle plate upward. The first engagement member is provided on the needle plate. The second engagement member is provided inside the bed portion, and is configured to fix the needle plate in a fixed position by being engaged with the first engagement member of the needle plate pressed downward against an urging force of the first urging member. The lock release mechanism is configured to release the engagement of the first engagement member and the second engagement member.

A sewing machine includes a needle plate, a bed portion, a first urging member, a first engagement member, a second engagement member, and a lock release mechanism. The bed portion is configured to support the needle plate. The first urging member is provided inside the bed portion and configured to urge the needle plate upward. The first engagement member is provided on the needle plate. The second engagement member is provided inside the bed portion, and is configured to fix the needle plate in a fixed position by being engaged with the first engagement member of the needle plate pressed downward against an urging force of the first urging member. The lock release mechanism is configured to release the engagement of the first engagement member and the second engagement member.

An overlock sewing machine includes an operating shaft that is slidable between first and second positions, and configured such that interlock switching and position switching mechanisms are operated when it is turned. The interlock switching mechanism includes a rotor that is rotatable together with the operating shaft as a single unit, an interlock switching member, and a first engagement target portion formed in the rotor. In the interlock state, setting the operating shaft to the first position engages an engagement portion of the interlock switching member with the first engagement target portion, which restricts operating shaft rotation. Sliding the operating shaft to the second position releases the engagement state between the engagement and first engagement target portions, enabling rotation of the operating shaft.

An overlock sewing machine includes an operating shaft that is slidable between first and second positions, and configured such that interlock switching and position switching mechanisms are operated when it is turned. The interlock switching mechanism includes a rotor that is rotatable together with the operating shaft as a single unit, an interlock switching member, and a first engagement target portion formed in the rotor. In the interlock state, setting the operating shaft to the first position engages an engagement portion of the interlock switching member with the first engagement target portion, which restricts operating shaft rotation. Sliding the operating shaft to the second position releases the engagement state between the engagement and first engagement target portions, enabling rotation of the operating shaft.

A sewing machine includes a main body and a quick release needle plate module. The main body includes a base seat having an inner frame, and an outer case that is mounted to the inner frame and that defines an accommodating compartment. The quick release needle plate module includes a catch member, and a needle plate that covers the accommodating compartment, that is detachably pivoted to a rear section of the inner frame, and that engages the catch member. The quick release needle plate module further includes a press member inserted through the outer case and the inner frame, and operable to push the catch member to disengage the catch member. The needle plate has a plate body that covers the accommodating compartment, and a resilient member mounted between the inner frame and the plate body for driving pivot action of the plate body away from the inner frame.

A sewing machine includes a main body and a quick release needle plate module. The main body includes a base seat having an inner frame, and an outer case that is mounted to the inner frame and that defines an accommodating compartment. The quick release needle plate module includes a catch member, and a needle plate that covers the accommodating compartment, that is detachably pivoted to a rear section of the inner frame, and that engages the catch member. The quick release needle plate module further includes a press member inserted through the outer case and the inner frame, and operable to push the catch member to disengage the catch member. The needle plate has a plate body that covers the accommodating compartment, and a resilient member mounted between the inner frame and the plate body for driving pivot action of the plate body away from the inner frame.

In order to prevent a replacement of the needle plate in the situation not suitable for replacing the needle plate, a needle plate detachable mechanism has a needle plate fixing unit for fixing a needle plate on a sewing machine body; a releasing unit for releasing a fixed state of the needle plate; and a fixing-release limiting unit for limiting a release of the fixed state of the needle plate when the needle is positioned below an upper surface of the needle plate or when the sewing machine motor is driven.

In order to prevent a replacement of the needle plate in the situation not suitable for replacing the needle plate, a needle plate detachable mechanism has a needle plate fixing unit for fixing a needle plate on a sewing machine body; a releasing unit for releasing a fixed state of the needle plate; and a fixing-release limiting unit for limiting a release of the fixed state of the needle plate when the needle is positioned below an upper surface of the needle plate or when the sewing machine motor is driven.

In order to prevent a replacement of the needle plate in the situation not suitable for replacing the needle plate, a needle plate detachable mechanism has a needle plate fixing unit capable of being switched between a fixed state where a needle plate is fixed to a sewing machine body and an unfixed state where the fixed state is released; and a switching mechanism which is connected with the needle plate fixing unit for switching the needle plate fixing unit between the fixed state and the unfixed state, wherein the needle plate fixing unit is prevented from being switched when the needle is positioned below an upper surface of the needle plate or when the sewing machine motor is driven.