Abstract: A sewing machine includes a sewing pitch setup unit configured to set up a given sewing pitch; a movement detection unit configured to detect a movement of a material to be sewn; a control unit configured to calculate a movement speed of the material on the basis of a movement amount of the material detected by the movement detection unit and to calculate a rotational rate for a sewing machine motor for operating a needle on the basis of the movement speed and the given sewing pitch; and an informing component configured to inform of magnitude of the rotational rate relative to a maximum rotational rate for the sewing machine motor.

Abstract: A sewing machine includes a rotational speed determination unit configured to determine a rotational speed instruction value on the basis of information from a movement detection sensor that detects movement of a workpiece and a predetermined sewing pitch amount, an upper limit rotational speed setting unit configured to set an upper limit rotational speed value, a rotational speed control unit configured to control a rotational speed to the rotational speed instruction value and control the rotational speed to the upper limit rotational speed value when the rotational speed instruction value reaches the upper limit rotational speed value, and a sewing machine motor driven at the controlled rotational speed to operate a needle. Rotational speed control of the sewing machine motor according to a movement amount of the workpiece is executed, but the rotational speed is controlled so as not to exceed the upper limit rotational speed.

Abstract: Provided with a cloth movement detection device and a sewing machine capable of precisely detecting a movement of a cloth. A cloth movement detection device includes: a light detection portion configured to detect a light for detecting a movement of a cloth; a body portion configured to be detachably attached to a presser bar of a sewing machine, the light detection portion being installed in the body portion; and a pressing support portion configured to be detachably attached to the body portion, a cloth pressing portion capable of contacting with the cloth being formed on the pressing support portion, wherein a window portion capable of transmitting the light is provided on a bottom surface of the body portion, and the cloth pressing portion is located lower than the bottom surface of the body portion in a state that the pressing support portion is attached to the body portion.

Abstract: Provided with a cloth movement detection device and a sewing machine capable of precisely detecting a movement of a cloth. A cloth movement detection device includes: a light detection portion configured to detect a light for detecting a movement of a cloth; a body portion configured to be detachably attached to a presser bar of a sewing machine, the light detection portion being installed in the body portion; and a pressing support portion configured to be detachably attached to the body portion, a cloth pressing portion capable of contacting with the cloth being formed on the pressing support portion, wherein a window portion capable of transmitting the light is provided on a bottom surface of the body portion, and the cloth pressing portion is located lower than the bottom surface of the body portion in a state that the pressing support portion is attached to the body portion.

Abstract: A sewing machine includes a feed amount setting part and a feed amount adjustment part. In the feed amount setting part, a forward feed amount for one stitch of forward stitching is set. In the feed amount adjustment part, the forward feed amount which is set by the feed amount setting part is compared with the maximum backward feed amount for one stitch of reverse stitching which is determined by a feed mechanism. Then, in the feed amount adjustment part, when the forward feed amount is larger than the maximum backward feed amount, the total amount of backward feed amounts for plural stitches of backward stitching is adjusted so as to coincide with the total amount of the forward feed amounts for one stitch or more of forward stitching.

Abstract: A sewing machine includes a feed amount setting part and a feed amount adjustment part. In the feed amount setting part, a forward feed amount for one stitch of forward stitching is set. In the feed amount adjustment part, the forward feed amount which is set by the feed amount setting part is compared with the maximum backward feed amount for one stitch of reverse stitching which is determined by a feed mechanism. Then, in the feed amount adjustment part, when the forward feed amount is larger than the maximum backward feed amount, the total amount of backward feed amounts for plural stitches of backward stitching is adjusted so as to coincide with the total amount of the forward feed amounts for one stitch or more of forward stitching.