A sewing machine includes at least one needle bar, a threading motor, a threading mechanism, a processor, and a memory. The threading mechanism is configured to pass an upper thread through an eye of a sewing needle. The memory is configured to store computer-readable instructions that, when executed by the processor, instruct the processor to perform processes. The processes include making one of a setting that prohibits operation of the threading mechanism and a setting that does not prohibit the operation of the threading mechanism. The processes include switching the operation of the threading mechanism by prohibiting the operation of the threading mechanism in a case where the setting that prohibits the operation of the threading mechanism is made, and permitting the operation of the threading mechanism in a case where the setting that does not prohibit the operation of the threading mechanism is made.

A method for calibrating one or more optical sensors on a sewing machine, including collecting data of one or more features of one or more predefined regions associated with the sewing machine, processing the data through one or more neural networks, wherein the one or more neural networks detect and recognize the one or more features of the one or more predetermined regions from the data, calculating one or more accuracy indicators of the one or more features from the data as compared to one or more trained features from the one or more neural networks, comparing the value of the one or more accuracy indicators to one or more indicator thresholds and adjusting one or more parameters of one or more optical sensors based on the comparison between the one or more accuracy indicators and the one or more indicator thresholds.

A method for calibrating one or more optical sensors on a sewing machine, including collecting data of one or more features of one or more predefined regions associated with the sewing machine, processing the data through one or more neural networks, wherein the one or more neural networks detect and recognize the one or more features of the one or more predetermined regions from the data, calculating one or more accuracy indicators of the one or more features from the data as compared to one or more trained features from the one or more neural networks, comparing the value of the one or more accuracy indicators to one or more indicator thresholds and adjusting one or more parameters of one or more optical sensors based on the comparison between the one or more accuracy indicators and the one or more indicator thresholds.

A presser foot device includes a pressing member and a guide member provided at the lower end of the pressing member. The guide member has an opening section provided to allow an upper thread to pass therethrough in a rotating direction of a rotary hook, and a restricting section provided to restrict movement of the upper thread in a direction opposite the rotating direction of the rotary hook. Upon determination that a direction in which a next stitch is to be formed belongs to a predetermined hitch-stitch forming area, detouring movement of a frame, holding the sewing workpiece, is carried out. This detouring movement includes moving the frame in such a direction in which the upper thread moves out of the opening section and then further moving the frame to a target position corresponding to the next stitch such that the upper thread abuts against the restricting section.

A presser foot device includes a pressing member and a guide member provided at the lower end of the pressing member. The guide member has an opening section provided to allow an upper thread to pass therethrough in a rotating direction of a rotary hook, and a restricting section provided to restrict movement of the upper thread in a direction opposite the rotating direction of the rotary hook. Upon determination that a direction in which a next stitch is to be formed belongs to a predetermined hitch-stitch forming area, detouring movement of a frame, holding the sewing workpiece, is carried out. This detouring movement includes moving the frame in such a direction in which the upper thread moves out of the opening section and then further moving the frame to a target position corresponding to the next stitch such that the upper thread abuts against the restricting section.

A presser foot of a sewing machine includes: a presser main body that presses a cloth; a guide base provided to the presser main body so as to form a single unit, and configured to guide a ribbon to be sewn to the cloth; a right guide and a left guide configured as members that are provided such that they can be relatively moved with respect to the guide base, that guide a position of the ribbon in the width direction, and that are arranged symmetrically with a position at which a sewing needle moves in a vertical direction as a base position; and an adjustment screw, a right guide bush, and a left guide bush, configured as a linking portion that links the movements of the right guide and the left guide such that they are positioned symmetrically with respect to the base position at all times.

A presser foot of a sewing machine includes: a presser main body that presses a cloth; a guide base provided to the presser main body so as to form a single unit, and configured to guide a ribbon to be sewn to the cloth; a right guide and a left guide configured as members that are provided such that they can be relatively moved with respect to the guide base, that guide a position of the ribbon in the width direction, and that are arranged symmetrically with a position at which a sewing needle moves in a vertical direction as a base position; and an adjustment screw, a right guide bush, and a left guide bush, configured as a linking portion that links the movements of the right guide and the left guide such that they are positioned symmetrically with respect to the base position at all times.

A sewing machine presser foot includes: a presser foot body including an attachment portion attached to a presser bar of a sewing machine, a supporting portion extending downward from the attachment portion , and a pressing portion in which, at a lower end of the supporting portion, a needle guiding hole having a string guiding groove for guiding a string is formed; and a cover member including a groove covering portion that crosses and covers the string guiding groove of the pressing portion, a supporting plate portion formed along the supporting portion continuously from the groove covering portion, and an attachment portion formed at an end of the supporting plate portion so as to be attached to the presser foot body. A right-side portion of the supporting plate portion of the cover member is fixed to the presser foot body A by the attachment portion.

The presser lifting mechanism of a sewing machine includes a cloth presser, a pressing rod which holds the cloth presser by a bottom end portion thereof, a rod holder which is fixed to the pressing rod, a pressing spring a bottom end portion of which is in contact with a top end portion of the rod holder and which pushes the cloth presser downward via the rod holder, a push-up member through which the pressing rod is inserted so as to be movable in the vertical direction and which is in contact with the rod holder from below and can pushed it up, a link body which is in contact with a bottom surface of the rod holder and is connected to the push-up member, and a presser motor which is linked to the link body and serves as a drive source for elevation and lowering of the cloth presser.

The presser lifting mechanism of a sewing machine includes a cloth presser, a pressing rod which holds the cloth presser by a bottom end portion thereof, a rod holder which is fixed to the pressing rod, a pressing spring a bottom end portion of which is in contact with a top end portion of the rod holder and which pushes the cloth presser downward via the rod holder, a push-up member through which the pressing rod is inserted so as to be movable in the vertical direction and which is in contact with the rod holder from below and can pushed it up, a link body which is in contact with a bottom surface of the rod holder and is connected to the push-up member, and a presser motor which is linked to the link body and serves as a drive source for elevation and lowering of the cloth presser.