Abstract: An electronic sewing machine capable of sewing a buttonhole having a circular stitching part. The machine is operative selectively in one of automatic and manual modes. In the automatic mode, bight position of a needle and feed position of a feed dog are automatically controlled according to stored bight and feed data. In the manual mode, the bight and feed positions determined by the stored data are adjusted by a data adjusting circuit. The machine comprises a circuit which supplies the data adjustment circuit with a signal to inhibit the adjustment of at least the feed data for each stitch to be formed in the circular stitching part.

Abstract: A sewing machine aurally informs an operator of abnormal conditions which accidentally have taken, or are taking, place by means of a vocal indication. One group of speech data corresponding to an accidentally occurring abnormal condition is selected from among plural groups of speech data according to a detection signal from a plurality of abnormal condition detectors disposed in the machine. A voice signal corresponding to the selected group of speech data is generated in relation to operation of a manual device e.g. a button such as a switch, for the start of sewing. The operator can hear the warning voice due to this vocal indication simultaneously with the operation of the manual button for the start, whereby he/she is prevented from starting of the machine while the abnormal condition exists.

Abstract: An electronic sewing machine capable of forming a buttonhole having a circular stitching part. The machine has manually operated members for setting thread thickness and button size. A stitch data generator is provided, which is capable of selectively generating one of plural different groups of stitch data for forming different buttonholes which have a different number of stitches at their circular stitching part. The specific group of stitch data is selected according to code signals fed in accordance with the positions of the manually operated members. The position of each stitch contained in the circular stitching part of the buttonhole is determined by each stitch data of the selected group. Thus, the desired buttonhole is sewn neatly without crowded or lean stitches.

Abstract: A diagnostic table which stores possible causes of certain abnormal conditions is accessed by corresponding push buttons for sequential vocalization by a sewing machine system, thereby helping the operator check the machine.

Abstract: An abnormal condition warning apparatus for a sewing machine is disclosed. Plural detecting means disposed in the sewing machine detect the occurence of abnormal conditions in which stitch forming instrumentalities are prevented from forming a desired stitch pattern, and each of the plural detecting means generates a detection signal according to the detection. Plural groups of speech data are permanently stored in memory means, and each of the groups is predetermined to represent one of the abnormal conditions in voice. Selecting means selects one group from the plural groups according to the detection signal, an electric signal is generated based on the selected group, and electroacoustic means disposed in the machine speaks one of the abnormal conditions in response to the electric signal.

Abstract: A buttonhole sewing machine for automatically forming a buttonhole including right and left parallel side stitching parts, and another stitching part connected to the side stitching parts. The machine has a switch for detecting front and rear ends of each side stitching part, and is capable of sewing the buttonhole in divided parts on opposite sides of a longitudinal centerline thereof so that the two side stitching parts are stitched in the same work feeding direction. The machine comprises a control circuit generating a feed change signal when the number of stitches being formed in one of the side stitching parts has become equal the total number of stitches of the other side stitching part less a predetermined number, and a feed adjusting circuit for reducing a work feeding increment for a time interval between generation of the change signal and a signal from the switch, to avoid a difference in length between the side stitching parts.

Abstract: An electromechanical actuator is formed in flat and thickness reduced configuration having a stator, a movable portion to drive or control a needle positioning mechanism and a work feed regulating mechanism or the like in response to electrical signals. Said stator portion includes a pair of parallel spaced yokes to define a single air gap therebetween, and a plate-like permanent magnet secured to an inner wall of at least one of said yokes, the magnet being magnetized so that oppositely directed flux fields are established within the air gap. Said movable portion includes planar armatures disposed in said flux fields to pivotally move with the fulcrums placed at the opposed peripheral portion, and exciting windings each carried by said armatures.

Abstract: An automatic thread regulating system having an adjustment mechanism for controlling the thread feed and takeup during the formation of a sewing machine stitch. A central processing unit calculates the length of thread required for a specific stitch formation based on work piece thickness and stitch length. This information is directed to the adjustment mechanism which thereby regulates the appropriate thread amount by feed rolls and a suction apparatus.