Abstract: A pluggable external wireless receiver module includes a housing, a power terminal unit, a receiver device, and a control terminal unit. The power terminal unit is mounted on the housing and is adapted for connection to a power source. The receiver device is mounted in the housing, and includes a receiver unit for receiving a wireless control signal, a processing unit for processing the control signal received by the receiver unit, and a driving unit controlled by the processing unit for generating a motor control output corresponding to the processed control signal. The control terminal unit is mounted on the housing, is connected to the driving unit of the receiver device, and is adapted for connection to a connector of a sewing machine, thereby transmitting the motor control output from the driving unit to the sewing machine for controlling operation of a motor of the sewing machine accordingly.

Abstract: In a method of wirelessly controlling a sewing machine, a wireless receiver module receives an initial signal transmitted wirelessly and continuously from a speed control module in response to a treading action thereon, and stores a preset security code portion of the received initial signal therein. Thereafter, the wireless receiver module receives an incoming control signal transmitted wirelessly from the speed control module in response to a treading action thereon, and controls operation of a motor unit in accordance with a speed control code portion of the received incoming control signal upon detecting that an identification code portion of the received incoming control signal matches the security code portion stored therein.

Abstract: A method of and an apparatus for producing an armature winding of a flat type motor is disclosed having a motor, a flyer rotated by the motor for feeding a wire for the armature winding out of a nozzle thereof, a bobbin member for winding the wire fed out from the flyer around the outer periphery thereof when the flyer is rotated around it to thereby form a unit coil, first and second moving members for moving the nozzle of the flyer to directions in parallel with and directions perpendicular to a plane formed by the rotation of the nozzle, a turn table capable of mounting a commutator of the center thereof and placing plural unit coils around the commutator, a pushing member for pushing the unit coil wound around the bobbin member to place on the turn table, a guide member for catching a portion of the wire connected between the nozzle and the unit coil placed on the turn table and guiding the catched portion of the wire near corresponding one of hooks of the commutator mounted on the turn table, a revolutio

Abstract: A controller for electric motors comprises a casing, a carbon pile resistor contained in a through hole of an insulating frame carried by the casing, a U-shaped spring conductor plate with an end secured to the insulating frame, a rotational plate pivotally supported on the casing, a first terminal connected to an end of the carbon pile resistor, and a second terminal connected to the conductor plate. The other end of the conductor plate is operatively connected to the rotational plate. Thus the other end of the conductor plate is biased and presses the other end of the carbon pile resistor in response to the rotation of the rotational plate.

Abstract: A speed control system for a motor comprises a main motor circuit for supplying the motor current to the motor from an AC power supply via a main switch, a full-wave rectifier circuit and a semiconductor element with a control electrode, variable voltage setting means connected to the full-wave rectifier circuit, charge-discharge element connected to the variable voltage setting means and impressed with a voltage set by the variable voltage setting means, and a trigger voltage supply element conducted for releasing the charges charged in the charge-discharge element to the control electrode of the semiconductor element as a trigger voltage when the charge voltage of the charge-discharge element reaches a predetermined level.

Abstract: A slide-type potentiometer for speed control of electric motors under control of a foot-pedal actuator mechanism comprising an actuating rod reciprocatably movable in the longitudinal directions thereof, a spring member for urging the actuating rod in one of the longitudinal directions, a contact supporting member having an electrical contact secured thereto and mounted on the actuating rod so as to be movable in the longitudinal directions along with the actuating rod, a resistor element positioned such that the electrical contact member is slidably moved on the resistor element upon movement of the actuating rod, and a housing for enclosing the contact supporting member and the resistor element, the housing has a through-hole through which one end portion of the actuating rod extends outwardly.

Abstract: There is provided a DC motor speed control system comprising a main motor circuit which supplies a motor current from an AC source through a full-wave rectifying circuit and a semiconductor element having a control electrode to a DC motor, a manually variable voltage setting means which is connected with the full-wave rectifying circuit, a charging circuit which is connected with the manually variable voltage setting means, a switching element having a control element which is connected with the charging circuit and, when the charged voltage in the charging circuit reaches a predetermined value, is made conductive to discharge the charging circuit thereby to supply a discharge current to the semiconductor element as a triggen current, a constant voltage element which is connected with the full-wave rectifying circuit, and a detecting means which detects the counter electromotive force induced in the motor.

Abstract: A speed control circuit for a series motor is disclosed which keeps the rotational speed of a motor constant by detecting the slight change of an electromotive force caused by the change of the load motor. A gate signal from a trigger signal generating element is provided to the base of a thyristor connected in series with the series motor. The gate signal is controlled by a control circuit.

Abstract: A speed control system for a motor comprising a main motor circuit supplying motor current to the motor from an A.C. power source through a semiconductor element provided with a control electrode, trigger voltage supplying means supplying trigger voltage to the control electrode of the semiconductor element, motor voltage detecting means for detecting voltage induced in the motor, and automatically variable resistance means having its resistance value varied automatically depending on the detected motor voltage. In the system, the trigger voltage supplied by the trigger voltage supplying means is controlled depending on the variation in the resistance value of the automatically variable resistance means, and the firing angle of the semiconductor element is retarded in response to an increase in the detected motor voltage and advanced in response to a decrease in the detected motor voltage.

Abstract: A motor driven sewing machine comprises pulse generator means for generating a first pulse associated with the first predetermined angular position and a second pulse associated with the second predetermined angular position of the main-shaft of the machine, and state-alternating means for alternatively changing its states between first and second states in response to the first and second pulses. The needle position and cloth feed are controlled in accordance with the states of the state-alternating means.

Abstract: A control apparatus for an electrically driven sewing machine with stitch pattern producing means comprises an electric signal generator for generating an electric signal related to at least one predetermined angular position of a main shaft of the sewing machine, set board means capable of setting therein a desired stitch pattern by means of a probe, and pattern detecting means for reading out cloth feed operation information and needle position information of the stitch pattern set at the set board means. The needle bar is set at a predetermined position in dependence upon the needle position information as read out, while cloth feed is effected in dependence upon the cloth feed operation information, whereby sewing operation is performed in the same stitch pattern as the one stored in the set board means.

Abstract: A motor speed control apparatus for an electrically-driven sewing machine capable of effecting single stitch comprises a main motor circuit for supplying a motor current to a motor from an AC power supply through a main switch and a semiconductor element with a controlled electrode, a first control means for controlling the semiconductor element in order to effect normal operation, a controller adapted to change between its first and second state so as to control the speed of the motor continuously when the first control means is energized, a second control means for controlling the semiconductor element for effecting single stitch, and a change-over means for changing over the operation between the first and second control means. The second control means includes means for setting the trigger voltage for conducting the semiconductor element, a switching element coupled with the trigger-voltage setting means, a bias means for energizing the switching element, and a charge-discharge circuit.