In a thread standing device capable of switching a plurality of spool pins between a stored state and a deployed state and a sewing machine having the thread standing device, an operability is improved during the switching operation. In a thread standing device, a plurality of spool pins can be switched between a stored state and a deployed state, operation portions related to a switching operation of the plurality of spool pins is provided, and the plurality of spool pins are configured to be switched from the stored state to the deployed state when the operation portions are operated.

A sewing machine includes a bed portion, a pillar, an arm portion, a cover, and a thread spool device. The cover is provided on the arm portion and is rotatable between a closed position and an open position. The closed position is a position in which a base surface faces an upper side of the arm portion and the base surface covers the upper side of the arm portion. The open position is a position in which the base surface is directed upward and the base surface does not cover the upper side of the arm portion. The thread spool device is provided on the base surface and including at least one thread spool pin, the thread spool device being capable of holding a thread spool on each of the at least one thread spool pin in a state in which the cover is disposed in the open position.

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.

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.

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.

In order to improve detachability of a needle plate, a needle plate detachable mechanism has a needle plate which is provided on a bed part of the sewing machine and made of a magnetic body; a magnet which is provided below the needle plate for fixing the needle plate by magnetic force; and a magnetic force changing mechanism which is connected with the magnet for changing the magnetic force acting on the needle plate by relatively moving the magnet with respect to the needle plate.

A sewing machine includes a bed portion, a pillar, an arm portion, a cover, and a thread spool device. The cover is provided on the arm portion and is rotatable between a closed position and an open position. The closed position is a position in which a base surface faces an upper side of the arm portion and the base surface covers the upper side of the arm portion. The open position is a position in which the base surface is directed upward and the base surface does not cover the upper side of the arm portion. The thread spool device is provided on the base surface and including at least one thread spool pin, the thread spool device being capable of holding a thread spool on each of the at least one thread spool pin in a state in which the cover is disposed in the open position.

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.

In order to improve detachability of a needle plate, a needle plate detachable mechanism has a needle plate which is provided on a bed part of the sewing machine and made of a magnetic body; a magnet which is provided below the needle plate for fixing the needle plate by magnetic force; and a magnetic force changing mechanism which is connected with the magnet for changing the magnetic force acting on the needle plate by relatively moving the magnet with respect to the needle plate.