JPS59236B2 - Continuous seaming device of sewing machine - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a continuous embroidery device for a sewing machine.
The purpose of this is to fix the embroidery fabric to the embroidery frame on a sewing machine that drops the needle at a fixed position or with a certain horizontal runout width, and then manually operate the embroidery frame to move the fabric forward, backward, left, and right relative to the needle drop position. The position of the needle drop on the fabric is determined by tracing the pattern of a model prepared in advance using a copying pen that moves in the same manner as the embroidery frame. After stopping once at the top dead center position, the intermittent movement is made to continue, like one stitch at the edge.

Conventional embroidery machines of this type generally operate the embroidery frame to position the needle drop, momentarily press the controller to sew just one stitch, move the embroidery frame again, and press the controller. In order to make a continuous line, the embroidery hoop cannot be moved when the needle is a cloth, even if you reduce the amount of pressure on the controller and rotate the sewing machine continuously at low speed. It is difficult to operate, as the sewing frame must be quickly moved while the fabric is above the fabric, and work efficiency is also poor.

The present invention allows the embroidery frame to move reliably without reducing the sewing speed by stopping the sewing machine needle once at the top dead center, and allows the sewing machine to set a safe and efficient sewing speed. Starting and stopping can be done by simple operations such as a hand switch provided on the copying pen.

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is the main body of the sewing machine, 2 is a clutch operation switching button for switching between enabling and disabling a clutch device for mechanically stopping the needle at top dead center, and 3 is a hand controller, 4 is a power switch, 5 is a stop button, 6, 7.8 are push buttons for specifying low speed, medium speed, and high speed, respectively, 9 is a push button for embroidery, 10 is an embroidery speed adjustment dial, and 11 is a 12 is an installation part for the pattern to be copied; 12 is a copying pen that can be moved back and forth and left and right on the pattern, and has a thin tip that can be designated as a seam point at any position on the pattern; 13 is an embroidery pen; This is a hand-held switch for starting and stopping, and the hand-held switch may be provided either at the grip portion of the pattern copying tool 12 or at the connection portion with the embroidery frame 14 near the grip portion.

Reference numeral 14 denotes an embroidery frame that is integral with the copying pen and moves in parallel thereto, and may be moved in a similar relationship such that each part is equally reduced or enlarged.

15 is an embroidery cloth attached to the embroidery frame, 16 is a power plug, and 17 is each cord.

FIG. 2 is a control circuit diagram showing a first embodiment of the present invention, the main parts of which are housed in the band controller 3 shown in FIG. Motor A mainly serves as a speed control section of the sewing machine motor, and motor B mainly serves as an embroidery control section.

Dl, D2D3. D4 is each diode that performs full-wave rectification of the power supply voltage.

5CR1 and 5CR2 are speed control thyristors connected in antiparallel to each other; oTrl, which is connected in series with the sewing machine motor M, is a transistor that supplies the gate current of each thyristor; D5. D6 is a diode, R1 and R2 are resistors, and the resistance value of R2 is set to be higher than that of R1 to form a thyristor 5.
The sensitivity of CR2 is slightly lowered than the sensitivity of SCR1, and in the low speed control region of the motor, only thyristor SCR1 is phase controlled, and eventually phase control from half wave to full wave is performed, enabling a wide range of speed control. .

Resistor R3 and R capacitors C1 and C2 are connected to each thyristor 5.
It is for protection of CR1, 5CR2, and R7 is a voltage dividing resistor for supplying gate current to each of these circuits.

ZDl is a Zener diode for power supply voltage fluctuation compensation, C
3 is a smoothing capacitor, R6 is a circuit protection resistor, and the voltage smoothed by the capacitor C3 supplies the collector current of the transistor Tr1.

6, 7.8 are the respective normally open switches S1. S2. S3 is closed, and normally open switch S4 and normally closed switch S, which are reset by the stop button 5, are closed and opened, respectively.

Reference numeral 9 indicates the embroidery push button.By operating the embroidery push button, the normally closed switch S6 is opened and the normally open switch S7 is closed.Then, by operating the stop button 5, the sewing machine returns to normal sewing.

Tr2 is a transistor for supplying a base current to the transistor Tr1, and the switches S1 . S2. When one of the capacitors S3 is closed, the switch S4 is closed in conjunction with this, so that the (→voltage) of the capacitor C3 is applied to its collector.

When the transistor Tr2 operates, the voltage dividing semi-fixed resistor R7, the voltage dividing resistor R5 and the transistor T
A control voltage divided by the base-emitter resistor R8 of r1 is supplied to the base of the transistor Tr1.

Ro, Rlo. R11 is a semi-fixed resistor, which sets the collector current of the transistor Tr2 and connects each switch S.
1. By operating S2゜S3, the motor M can be set to low speed, medium speed,
Set the speed to correspond to high speed.

R12 is a semi-fixed resistor, and its charging time constant constitutes a minute base current supply circuit of the transistor Tr via the capacitor C4, and the speed specifying switch S1. S2.
Immediately after S3 is operated, while transistor Tr2 is inactive, thyristor SCR1 is activated to control motor M at an extremely low speed.

S6 is a switch for discharging the charge of the capacitor C4.

ZD2 is a Zener diode, which operates the transistor Tr2 when the capacitor C4 is charged to a constant voltage and switches the switch S1. S2. S
This is to enable the selected switch No. 3 and stabilize the extremely low speed operation time, but during this extremely low speed operation time, immediately after selecting the speed with the band controller 3, move the hand to the cloth to be sewn and take a normal working posture. It is set so that the selected speed is reached after .

5CR3 is a thyristor for controlling the brush line, and is connected in parallel with the thyristor SCR.

Tr3 is a transistor and supplies the gate current of the sCR3.

D7 is a diode, R13 is a current limiting resistor, R14 is a gate protection resistor of the thyristor 5cR3, and ZD3 is a Zener diode for protecting the transistor Tr3.

The switch S7 has its connection point a connected to the power supply V at the switch 4.
The other end is connected to the hand switch 13, a variable resistor R15 connected to the embroidery speed adjustment dial 10,
It is connected to a series circuit of a resistor R16, a diode D8, and a capacitor C5, and the other end of the capacitor is connected to the cathode side of the thyristor 5cR3, and the capacitor is connected to the hand switch 13 on the condition that the switch S7 is closed.
When the capacitor C6 is closed, it is charged with a charging time constant determined by its static constant capacitance and resistors R15t, R16, etc., and when the charging voltage of the capacitor reaches the breakover voltage of the constant voltage discharge element 5BS1, the charge accumulated in the capacitor C6 is discharged from the resistor. R1□, transistor T via semi-fixed resistor R16
It is designed to be discharged as the base current of r3.

The discharge time is based on the capacitance and the time constant of these resistors.During the discharge time, the thyristor SCR3 is controlled to a minute current in order to keep the rotation of the motor M at a suitable slow speed. There is.

The charging and discharging described above are repeated and the charging time brings the motor M to rest.

C6 is a capacitor for preventing malfunction of the discharge element 5BS1, and R19 is a base protection resistor of the transistor Tr3.

The clutch operation switching button 2 in FIG. 1 is used to disable a clutch device (not shown) that mechanically stops the needle of the sewing machine at the top dead center for normal sewing and to enable it for embroidery sewing. When this is enabled, when there is no driving force from the motor M, the stopping mechanism is reset and the sewing machine is mechanically stopped near the top dead center of the needle.

The resistor R16 is adjusted so that the sewing machine stops just before the current of the motor M is turned off due to the end of the discharge time of the capacitor C5.

In the configuration shown in FIG. 2 above, turn on the power switch 4,
Operate the clutch operation switching button 2 in Fig. 1 to disable the top dead center stop mechanism (not shown) for normal sewing, and press either the speed designation push button 6, 7, or 8. When operated, switches S1°S2. The switch specified by that operation in S3 is closed, and switch S4 is closed.
Switch S5 is opened and transistors Tr2. Tr1
The thyristors SCR, 5CR2 are controlled by the operation of the motor M, and the motor M is operated at a specified speed.

When the stop pushbutton 5 is operated, the switch S1. S2.
S3゜S4 is open and thyristor S CR1,5CR
At the same time, the gate current of C2 is cut off, and the switch S is closed to discharge the charge in the capacitor C4 in preparation for the next motor start.

Next, in order to perform embroidery, operate the clutch activation switching button 2 to enable the stop mechanism, and when the embroidery button 9 is operated, the switch S5 is opened and the thyristors 5CR1 and 5CR2 for speed control are disabled from then on. .

The switch S7 is closed, and the hand switch 13 becomes effective from then on.

Align the pen 12 by following the line starting point of the pattern to be copied in the setting section 11, attach the cloth 15 to the embroidery frame 14 so that the line starting point is at the desired position, and press the hand switch 13, the capacitor C5 will be activated. Start charging.

At this time, the motor M does not start rotating, but when the charging voltage of the capacitor reaches the breakover voltage of the constant voltage discharge element SBS1, the capacitor is discharged and the transistor Tr3 is activated, and the thyristor 5CR for seaming control is activated.
3 operates, the motor M starts rotating, and is energized until the discharge ends, but when the needle of the sewing machine reaches the top dead center, the stop mechanism is activated and the sewing machine is forcibly stopped.

When the power supply stops, the stop mechanism is reset.

If the copying pen 12 is designated as the second stitch on the pattern to be copied during this top dead center stop period, the embroidery frame 14 will also move in parallel, so it will move along the same trajectory as the pattern on the model. do.

During this time, the capacitor C6 is recharged and discharged again, and the motor M rotates.

The discharge time constant of the capacitor C5 is determined so that the motor is forcibly stopped after one rotation, and the motor current is cut off immediately after that.

Thereafter, embroidery stitching is performed in the same manner, with the stitches being successively advanced.

The rest time of the motor M can be adjusted using the embroidery speed adjustment dial 10.

When you want to stop, just release the hand switch 13.

When the embroidery is finished, the stop push button 5 is operated, and the switch S6 is closed and the switch S7 is opened to prepare for normal sewing.

Fig. 2 shows an example in which the stop mechanism forcibly stops the sewing machine against the rotational force of the motor M and then cuts off the current, while Fig. 3 shows an example in which the stop mechanism of the sewing machine performs the stopping operation during continuous embroidery. This is an embodiment in which the belt pulley (none of which is shown) is idled and the motor current is cut off after a certain period of time to reset the stop mechanism. Although the speed control section has the same configuration and the explanation thereof will be omitted, the connection point a of the switch S7 was connected to the power switch 4 in FIG. The connection point between and motor M? This is connected.

C mainly serves as an embroidery control section.

Tr4 is a transistor that supplies gate current to the thyristor 5CR3 via a diode D.

The base current of the transistor is the resistance R21, the diode D1o, and the resistance R22? R15, switch 13. S7
, OC7 supplied through the resistor R20 is a capacitor for preventing malfunction of the transistor Tr4, and R23 is a protection resistor.

Zener diode ZD4 is for protection of transistor Tr4, and Dll is a diode.

Tr5 is a transistor for nullifying the gate current of the thyristor 5CR3, and its collector current short-circuits the gate of the thyristor 5CR3 via the diode Dll.

ZD5 is a Zener diode for transistor protection.
R24 is a circuit protection resistor.

C8 is a capacitor that is charged by the terminal voltage of the motor M via the resistor R20, switches S7, 13, resistor R15, diode D1□, Zener diode ZD6, and resistor R25 when the thyristor 5CR3 is firing. There is.

5BS2 is a constant voltage discharge element, and when the charging voltage of the capacitor C3 reaches its breakover voltage, the capacitor charge is discharged and supplied as the base current of the transistor Tr.

The resistor R15 is for adjusting the charging time constant of the capacitor C8, and the semi-fixed resistor R26 is for adjusting the discharging time constant.

R27t R26 is a circuit protection resistor, R2 is a discharge resistor for completely discharging the charge when capacitor C3 is not energized, and Zener diode ZD6 interrupts the circuit of capacitor C6 when thyristor 5CR3 is not firing. The purpose is to enable the switch 130 function and enable the charging circuit of the capacitor C8 at the time of ignition.

C0 is a capacitor for preventing malfunction of the discharge element 5BS2. In the configuration shown in FIG. 3 with 0 or more, the power switch 4 is turned on, and the clutch operation switching button 2 shown in FIG. 1 is operated to activate the stop mechanism (not shown). , and press embroidery button 9.
When the switch S7 is turned on, the switch S7 closes, and the hand switch 1
When 3 is pressed, the base current is supplied to the transistor Tr4 through the resistor R21, and the transistor Tr4 enters the operating state, and the thyristor 5C
R3 fires and motor M rotates.

At the same time, capacitor C8 starts charging via resistor R20 and the like.

When the needle of the sewing machine reaches the top dead center, the upper shaft of the sewing machine is forcibly stopped by the stop mechanism, and the motor and the sewing machine belt wheel idle.

When the charging voltage of the capacitor C8 reaches the breakover voltage of the constant voltage discharge element 5BS2, the transistor Tr5 operates to make the thyristor 5cR3 non-conductive for a certain period of time.

Here, the operating time of the motor M, that is, the capacitor C3
The charging time for the motor M is adjusted by the embroidery speed adjustment dial 10, and the current cutoff time for the motor M is controlled by the semi-fixed resistor R26.
adjusted by.

When the thyristor 5CR3 becomes non-conductive and the motor M stops, the stop mechanism of the sewing machine is reset and prepares for stopping after the next 01 revolutions.

Thus, embroidery is continuously performed while the switch 13 in FIG. 2 is pressed.

Next, the control block diagram of FIG. 4 will be described as an embodiment in which continuous embroidery sewing is possible by electrically controlling the sewing machine to stop each stitch without using a stopping mechanism.

In this case, the clutch operation switching button 2 shown in FIG. 1 becomes unnecessary.

In the figure, the speed regulator is the stop button 5 in Figure 1 to stop the sewing machine or specify the speed of normal stitching.
, low speed, medium speed, and high speed designation pushbuttons 6.7.8, the output of which constitutes one input of the speed control circuit.

The normal stitching/embroidery stitching switching device uses its output as the other input of the speed control circuit, and is reset by the stop button 5 in FIG. The control circuit is enabled, and by operating the embroidery push button 9, a logical value of 0 is set to designate continuous embroidery, and the speed control circuit is disabled.

The output of the speed control circuit operates a motor drive circuit to drive the sewing machine motor.

The output of the needle position detection device has a logical value of 1 in a predetermined section where the needle is near the top dead center, and is O in other sections.
It is set so that

The embroidery on/off signal generator is set so that when the hand switch 13 in FIG. 1 is pressed to start embroidery, the logic value is 1, and when it is released to stop the embroidery, the logic value is O.

F is a flip-flop circuit which is the main element for generating a fixed position stop signal and a drive signal for the sewing machine motor, and the positive side output terminal Q is connected to one input terminal of an AND circuit AND1, and the other input terminal of the AND circuit The terminal receives the output of the switching device via the inverter IN, and the output side thereof is connected to the motor drive circuit, and when the output of the AND circuit is 1 during embroidery sewing, the motor drive circuit is switched on. The sewing machine motor is designed to rotate at an extremely low speed.

The output terminal Q is connected to a delay circuit TD1, the output side of the delay circuit is connected to one input terminal of an AND circuit AND2, and the other input terminal of the AND circuit is connected to a needle position detection device. A delay circuit TD is set to allow the sewing machine to escape from a fixed position (for example, a position where the needle is in a predetermined section near top dead center) after the output terminal Q becomes 1.
a signal that becomes 1 after the set time of 1 has elapsed;
The timer T is operated via the AND circuit AND2 with the output 1 when the sewing machine escapes from the home position and detects the home position again after one revolution, and the reset terminal R of the Noritsubu flop circuit F is set to 1 to output the positive side. The motor driving circuit is opened by setting Q to 0, and the motor braking circuit is operated for a certain period of time to stop the sewing machine motor.

The negative output Q of the flip-flop circuit F is a delay circuit TD.
2, and the delay circuit has a stop time for the sewing machine including the motor braking time set by the timer T, which can be adjusted using the embroidery speed adjustment dial shown in FIG.

The output side of the delay circuit TD2 is connected to one input terminal of the AND circuit AND3, the other input terminal of the AND circuit is connected to the screen on/off signal generator, and the output terminal of the AND circuit is connected to the flip-flop circuit. In the configuration shown in Fig. 4, when the normal stitching/embroidery stitching switching device is set to embroidery stitching and the embroidery on/off signal generating device generates an on (embroidery start) signal, At this time, when the positive side output Q of the flip-flop circuit F is 1, the sewing machine motor starts rotating immediately, and when the negative side output Q is 1, the positive side output of the flip-flop circuit F is output after a certain period of time has elapsed by the delay circuit TD2. Q is set to 1, and in any case, when the sewing machine motor is driven and the needle position is detected, the positive side output Q of the flip-flop circuit F becomes O, and the motor circuit is cut off. At 0, the motor is braked and stopped, and after a pause time set by the delay circuit TD2, the motor is rotated again.

At the start of this re-rotation, the needle position detection signal is 1, but since the output of the delay circuit TD1 is 0, the braking circuit does not operate and escapes from the detection position, and the detection signal after one revolution of the sewing machine is 1. The braking circuit operates when

After that, the operations of rotating, stopping at a fixed position, pausing, and re-rotating are repeated at regular intervals, so the copying pen 12 is rotated at each pause time.
Continuous embroidery is performed by moving the button according to the pattern on the model.

As described above, according to the present invention, during embroidery sewing, the sewing machine rotates at a constant cycle and is operated intermittently, stopping once at the top dead center of the needle, etc. During the embroidery line, the sewing machine simply traces the pattern on the model with a copying pen or the like. It is easy to operate because you just trace with a spot, and the needle stops after each stitch, so you can move the copying pen rhythmically by listening to the stop of the sewing machine without worrying about the fabric or the needle. Since it can be started and stopped easily, it is easy to operate, and can be made into a safe and efficient continuous embroidery sewing machine, which is a highly effective invention in industrial practice.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embroidery sewing machine showing an embodiment of the present invention, FIGS. 2 and 3 are control circuit diagrams showing an embodiment of the present invention, and FIG. 4 is a circuit block diagram of yet another embodiment. It is. In the figure, a clutch operation switching button 2 is an operation section for switching between enabling and disabling stopping means including a clutch device (not shown), the motor braking circuit shown in FIG. 4 is a stopping means, and the embroidery speed adjustment dial 10 is an adjusting section. , 11 is an installation part for the pattern to be copied, 12 is a pattern copying tool, 13 is a hand switch, 14 is an embroidery frame, 15 is a cloth to be sewn, capacitors C6 and C8, and a flip-flop circuit F are main elements of the energization control means. , M is a sewing machine motor.

Claims (1)

[Claims] 1. An embroidery frame to which a fabric to be sewn can be attached and a needle drop position with respect to the fabric movable; an installation part for a pattern to be copied; and an embroidery frame that is movable in a fixed or similar relationship to the embroidery frame. a pattern copying tool that allows the pattern to be copied to be specified by operating the pattern to be copied as each stitch point, and a hand provided at or near the pattern copying tool for instructing the start and stop of embroidery stitching. a switch, a stop means that starts operating in response to the instruction to start embroidery stitching and temporarily stops the sewing machine with the needle at the top dead center for each stitch; a sewing machine comprising: an energization control means that controls the energization of the sewing machine motor to be cut off and then controls the energization to return to rotate the sewing machine again when a set time has elapsed; and an adjustment section that adjusts the set time. Embroidery device.