Abstract: The sewing machine includes a presser foot that is lowered to press a workpiece cloth; a presser foot lifting lever operating the presser foot; a thread tension mechanism including a thread tension regulator capable of adjusting the thread tension of a needle thread and opening the thread tension regulator based on the lifting operation of the presser foot lifting lever; and a thread guide groove guiding the needle thread at least to the thread tension mechanism, upon carrying out the thread hooking work. The sewing machine further includes a detector detecting a lifting operation of the presser foot lifting lever; a covering member which is movable between a closed position where the covering member covers at least a part of the thread guide groove and an opened position where the covering member opens the thread guide groove. The covering member is moved to the closed position when the presser foot is in a lowered state.

Abstract: When controlling a search for a target track on an optical disk having tracks on which data are recorded, the track-search control apparatus determines whether or not the optical disk is a DVD-RW disk. Then the apparatus calculates the number of tracks between the position of the currently detected track and the position of the target track, and calculates the number of correction tracks with which to correct the calculated number of tracks when the optical disk is determined to be a DVD-RW disk. Further, the apparatus executes the search for the target track based on the calculated corrected number of tracks.

Abstract: A method and apparatus for optical disc discrimination, which can discriminate immediately and correctly the types of a plurality of optical discs having different record densities of recorded information from each other.

Abstract: When controlling a search for a target track on an optical disk having tracks on which data are recorded, the track-search control apparatus determines whether or not the optical disk is a DVD-RW disk. Then the apparatus calculates the number of tracks between the position of the currently detected track and the position of the target track, and calculates the number of correction tracks with which to correct the calculated number of tracks when the optical disk is determined to be a DVD-RW disk. Further, the apparatus executes the search for the target track based on the calculated corrected number of tracks.

Abstract: When a trace mode is started, a needle and a presser foot are moved relative to an embroidery frame. When a STOP key is pressed, moving is temporarily stopped, and the operator can visually check a positional relationship between the needle and the embroidery frame. When it is necessary to check the positional relationship in detail, a DOWN key is pressed and the presser foot is lowered independently of the needle, so that the operator can visually check the positional relationship between the presser foot and the embroidery frame.

Abstract: When a trace mode is started, a needle and a presser foot are moved relative to an embroidery frame. When a STOP key is pressed, moving is temporarily stopped, and the operator can visually check a positional relationship between the needle and the embroidery frame. When it is necessary to check the positional relationship in detail, a DOWN key is pressed and the presser foot is lowered independently of the needle, so that the operator can visually check the positional relationship between the presser foot and the embroidery frame.

Abstract: A correction apparatus is designed to correct sewing data used on a sewing machine that forms an embroidery pattern on a cap by moving a needle bar upward and downward and a frame holding the cap in the X- and Y-axis directions. In the correction apparatus for correcting sewing data, the correction apparatus first reads sewing data as an original data, then finds the coordinates of a stitch point for each stitch from the read original data. The correction apparatus corrects the X coordinate of the stitch point based on a correction value that varies according to the Y coordinate, to create an execution data different from that in the original data. The correction value is calculated using the coordinate data of the Y-axis direction as a variable and a correction parameter that can be changed as a constant.

Abstract: When a stitch data compensation device detects that a control code which indicates a movement of a work cloth is added to the current and next stitch data, it corrects an X-direction movement amount and a Y-direction movement amount for the current stitch data according to an angle between a stitch to be formed based on the current stitch data and a consecutive stitch to be formed based on the next stitch data. When sewing is made on a sewing machine using the stitch data corrected by the stitch data compensation device, the shrinkage of the work cloth that would occur due to each stitch sewn thereinto can be prevented, which will result in preventing an uneven finished pattern, such as a gap in a satin pattern, a jagged fill pattern, and stitches to be made on the return when the sewing direction is reversed deviating from the ones already made on the go when running stitching is selected, assuring fine stitches will be formed on the work cloth.

Abstract: A sewing machine includes a plurality of needle bars for performing stitching with multiple needle threads. The needle threads have diameters, tenacity, and stretchability different from one another. Sewing parameters inherent to each of the needle threads are beforehand determined. The parameters are maximum sewing speed, thread breakage sensitivity, thread residual amount, needle-rotary hook meet angle, workpiece fabric feed timing, and feed pitch. A spindle motor, a thread cutting motor, a rotary hook drive motor, an X-axis motor, and a Y-axis motor are controlledly driven based on the selected parameters inherent to the just used needle thread.

Abstract: A multihead sewing machine includes a sewing machine motor, a main shaft rotated by the sewing machine motor, a plurality of sewing needles driven by the main shaft, a plurality of shuttles for capturing thread loops in cooperation with the sewing needles respectively, each shuttle having a hook shaft, and a plurality of shuttle driving motors for rotating the hook shafts of the shuttles independent of the sewing machine motor respectively. The sewing machine motor and the shuttle driving motors are controlled so that the sewing machine motor and each shuttle driving motor are rotated in synchronism with each other. Loss of synchronism of each shuttle relative to the corresponding sewing needle is detected. Rotation of the main shaft is stopped in an abnormal condition in which the loss of synchronism has been detected with respect to at least one of the shuttles.

Abstract: In a presser foot device of a sewing machine, a presser foot is vertically movably supported to a sewing machine body frame by a presser bar. A drive device moves the presser bar up and down in accordance with a drive signal. A sensor detects when the presser foot is raised close to a top dead center position, that is, a predetermined position. Based on the detection by the sensor, a control device controls the drive signal for the presser foot drive device.

Abstract: A sewing machine including a needle bar having a sewing needle, a spindle for driving the needle bar, a bed portion movable selectively to a using position or a retracted position, and a rotary hook housed in the bed portion. A stitch is formed by the cooperation of the sewing needle and the rotary hook. A rotary hook drive motor is provided in the bed portion for driving the rotary hook. A sensor is provided for detecting a position of the bed portion. The needle bar and the spindle is selectively disconnected from each other. If the bed portion is out of the using position, and this out position is detected by the sensor, the needle bar is released from the spindle for stopping the sewing needle. Further, in this case, the rotation of the rotary hook drive motor is also stopped.