A sewing machine having a device for manually changing a feed dog (10), including the feed dog (10) and a feed-dog holder (30). The feed-dog holder (30) is disposed in an arm bed (103) that is associated with the sewing machine, and the feed dog (10) is receivable in a clearance (31, 81) of the feed-dog holder (30). The feed dog (10) that is located in the clearance (31, 81) has a support face (15) which may be disposed parallel with the surface of a sewn-product support which may contain a needle-hole plate (113) or be configured as a needle-hole plate (113), the sewn-product support and/or the needle-hole plate (113) may at least partially be formed by the surface of the arm bed (103), and the support face (15) may be received in an opening (140) of the needle-hole plate (113). The feed dog (10) is fastenable in the clearance by a fastening element (40, 82, 83) or of a setting element (50) such that the support face (15) is alignable so as to be substantially parallel with the surface of the sewn-product support or of the needle-hole plate (113). The fastening element (40, 82, 83) or the setting element (50) is releasably held in the feed-dog holder (30).

In feed dog mounting/unmounting mechanism, lever is slidably provided to feed base in the front-rear direction, and is forced backward by a lever force-applying spring. Upon sliding lever rearward, fixing target portion of feed dog 22 is fixedly held by base-side fixing portion of feed base and lever-side fixing portion of lever arranged in the front-rear direction. Stopper is provided to feed base so as to be movable in the upper-lower direction, and holds lever. When feed dog is mounted, stopper is pressed downward by feed dog, which moves stopper so as to allow lever to slide. With this, lever is slid due to force applied by the lever force-applying spring, thereby allowing fixing target portion to be held, interposed between base-side fixing portion and lever-side fixing portion.

In feed dog mounting/unmounting mechanism, lever is slidably provided to feed base in the front-rear direction, and is forced backward by a lever force-applying spring. Upon sliding lever rearward, fixing target portion of feed dog 22 is fixedly held by base-side fixing portion of feed base and lever-side fixing portion of lever arranged in the front-rear direction. Stopper is provided to feed base so as to be movable in the upper-lower direction, and holds lever. When feed dog is mounted, stopper is pressed downward by feed dog, which moves stopper so as to allow lever to slide. With this, lever is slid due to force applied by the lever force-applying spring, thereby allowing fixing target portion to be held, interposed between base-side fixing portion and lever-side fixing portion.

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.

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.

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 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 needle plate attaching/detaching mechanism includes: a needle plate fixing portion rotatably provided below a needle plate mounted on a sewing machine main body, and movable between a fixed position fixing the needle plate to the sewing machine main body and a non-fixed position where the fixing is released; a driving gear jointly rotatably coupled to the needle plate fixing portion; a transmission mechanism switchable between a transmission state transmitting driving force from a motor to the driving gear and a disconnection state disconnecting the transmission; and an operating member including a manual gear transmitting manual operating force to the driving gear. When the operating member is non-operating, the transmission mechanism is set to the transmission state, and the manual gear is disconnected from the driving gear. In the operating state, the operating member switches the transmission mechanism from transmission to disconnection, and the manual and driving gears are coupled.