JPS6250577U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a front view, FIG. 2 is a speed control circuit diagram, and FIG. 3 is a logic circuit diagram. In the figure, 2 is a needle, 3 is a main shaft of the sewing machine, 4 is a sewing machine, 5 is a DC motor, 7 is a foot pedal, 11 is a toe-side depression signal generator, 12 is a heel-side depression signal generator, and 13 is a speed control. variable resistor, 1
6 is a driving power transistor, 17 is a braking power transistor, 19 is a speed control unit, 2
2 is a variable resistor for low speed setting, 23 is an input terminal, 2
5 is a first reed relay, 26 is a second reed relay, 27 is a third reed relay, 37 is a position detector,
38 is a Hall element for detecting the needle down position, 39 is a Hall element for detecting the needle up position, 40 is a Hall element for detecting thread trimming position, 41 is a magnetic pole wheel, 42 is a magnetoresistive element for speed detection, 45 is the first D type flip-flop, 46 is a second D type flip-flop, 47
52 is a counter, 53 is a counting circuit, 54 is a stitch number setting device, 55 is a third D-type flip-flop;
is a comparison circuit.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A sewing machine main shaft for moving the needle up and down, a driving means for driving the sewing machine main shaft, and a device connected to the driving means to perform drive control based on the operation of a foot pedal. a drive control means; a pulse generator that generates a pulse signal synchronized with rotation of the sewing machine main shaft rotated by one-way depression of the foot pedal; and a pulse generator configured to count the pulse signal generated from the pulse generator. counting means for generating a count end signal when the number of pulses is reached; means for disabling the drive control means based on the count end signal of the counting means; and means for disabling the drive control means based on the count end signal of the counting means; needle fixed position stopping means for stopping the needle upward or downward regardless of pedal depression; and based on the count end signal, the needle fixed position stopping means stops the needle at the upper or lower position to stop the needle at the predetermined position. After several stitches have been completed, the drive control means is enabled again in response to the release of the one-way depression of the foot pedal, and the main shaft of the sewing machine is driven by the next one-way depression of the foot pedal for correction stitching. means for rotating the main shaft of the sewing machine without sewing the predetermined number of stitches while the foot pedal is depressed in one direction when the correction stitch is performed; 1. A sewing machine characterized by comprising means for cutting the thread by depressing the foot pedal in the other direction, and making it possible to sew the predetermined number of stitches again by depressing the foot pedal in the next direction. 2. Utility model registration according to claim 1, wherein the needle fixed position stopping means stops the needle in a downward position based on a count end signal of the counting means, regardless of whether the foot pedal is depressed. sewing machine. 3. The counting means includes a counting circuit whose state sequentially changes according to the count of the pulse signal, and a reading setting means for reading out any one state of the counting circuit according to the state change of the counting circuit. A sewing machine according to claim 1 or 2 of the utility model registration claim.