JPS6047873B2 - Corner stitch control device for double needle sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a corner stitch control device for a two-needle sewing machine that automatically performs a predetermined corner stitch in a sewing machine having two needles arranged at a predetermined distance from each other on the left and right sides. In particular, the present invention relates to a device that counts the number of stitches (stitches) and performs a predetermined corner stitch.

The object of the present invention is to provide a device for ensuring corner stitching by a two-needle sewing machine. An embodiment of the present invention will be described with reference to the drawings.The main shaft (not shown) is rotatably supported on the machine frame of the sewing machine head placed on a table.
At the rear, a belt 2 is passed between an electromagnetic clutch motor (not shown) and a pulley 3 is fixed so that the main shaft rotates in conjunction with the electromagnetic clutch motor. A needle position detection device 4 is provided which detects the main shaft rotation angle corresponding to the vertical position of the needle bar which moves up and down once per rotation. The needle position detection device 4 is designed to detect a rotation angle slightly behind the top dead center of the needle bar. An electromagnetic clutch motor intermittently opens and closes a clutch within the motor in conjunction with the energization and deenergization of an electromagnet controlled by a control circuit (not shown), and drives the motor at a set rotation speed proportional to the amount of pedal depression. The speed is controlled by a circuit to rotate the shaft. Needle bars 6a and 6b with needles 5a and 5b fixed to their lower ends are arranged on the left and right sides perpendicular to the cloth feeding direction, and are supported on the jaw part 7 so as to be movable up and down in synchronization with the main shaft. , the well-known pause mechanism 8, which normally receives an acting force that maintains it in an inactive state, becomes active, and the left and right needle bars 6a, 6b are appropriately disconnected from the main shaft and raised. One end of the support shaft 9 rotatably supported on the machine frame 1 about a fixed straight line parallel to the cloth feeding direction is connected to the rest mechanism 8, and the tip end is connected to the other end. Fix the base of the lever 10 placed in front of the hole 7, and move the lever 10 around the support shaft 9.
For example, when the needle bar 6a on the left side in Figure 1 is rotated clockwise in Figure 1, and when the needle bar 6a on the right side in Figure 1 is rotated counterclockwise, the needle bar 6b on the right side in Figure 1 is brought to rest. At the same time, when the needle is placed in an intermediate position between the clockwise direction and the counterclockwise direction, both the left and right needle bars 6a and 6b are activated, and the pause mechanism 8 is inactivated. . A cam plate 16 is fixed to the rear of the connection portion of the support shaft 9 with the stop mechanism 8, and is rotatable around a shaft 17 parallel to the support shaft 9. a coiled spring 1 supported by the sewing machine frame 1 and having one end fixed to the sewing machine frame 1;
8, the engaging body 19 always receives a force acting to the left in FIG.
The end of the locking part 20 is formed into a forked shape, and one side of the locking part 20 is bent forward.The inner end surface of the locking part 20 is arranged opposite to the front end surface of the cam plate 16, and is engaged when the lever 10 is in the intermediate position. The inner end surface of the portion 20 is engaged with the protrusion 15 of the cam plate 16 to maintain the engaging body 19 in the right rotation position in FIG. When the cam plate 16 is rotated to one or the other position, the notch 21a on both sides of the protrusion 15 of the cam plate 16
or 21b, the engaging body 19 is rotated to the left in FIG. Further, the support part 21 protruding to the side of the engaging body 19 fixes the tip of the plunger 23 of the electromagnet 22 which is operated by pressing the operating rod 11 arranged in front of the machine frame.
When the plunger is actuated, the engaging body 19 is rotated to the right in FIG. 2 against the acting force of the winding spring 18 until the engaging portion 20 engages with the projection 15 of the cam plate 16. It is related to. In front of the sewing machine head on the top of the table 1, there are a total of nine needle selection buttons 12 arranged in three rows and rows that control an electric circuit (to be described later) to set the number of square stitches using a single needle. A switch button group is arranged, including a single manual button 13 that allows the number of stitches to be set as desired, and a single LOCK button 14 that maintains the electric circuit set by the selection operation of these buttons. The button 14 is locked in the pressed position by one press operation, and is released from the lock by pressing it again. Next, to explain the electric circuit of this embodiment, the terminal Vc is logically high when the power is turned on.
level voltage is applied, G is a known NAND gate, 1
is an inverter, 0R is an exclusive or gate, F
F is an RS flip-flop circuit, and Ff is a D flip-flop circuit.

i Stitch number setting circuit (Fig. 4) A. SW-I. The SW is an open/close switch that is closed by pressing each part of the needle selection button 12, and corresponds to stitches 1 to 9 in sequence, and MANU. SWl
3 is an open/close switch which is freely closed by pressing the manual button 13; LOCK. SW is an open/close switch that closes when the LOCK button 14 is pressed.

D. C is A. SW-1. Nine input parts a connected to SW
-1, and when an L-level input 7 is generated from a switch connected to one of each input section, the number of stitches corresponding to that switch is converted into a binary code and A
- Generate inverted outputs at the four outputs of the hill. B and R are bistable latches having an A-D input section that receives the outputs of decoders D and C(7)'A-h, and when the input of the latch input section jl falls from H to L, the A- An output obtained by inverting the D input is generated and held at Na-'Qd, and ? a
−? d output is inverted by 121 to 124 and becomes U in Figure 5.
, ■, Connect to W, X. P. S is an oscillator that instantaneously generates an H signal when the power is turned on, and this instantaneous signal makes the transistor Trl conductive, causing the set input of FFl to instantaneously become L, making the output of FFl L;
B. with the output of B. on L-H. A rising signal is input to the latch input section j of R. 11 Sewing machine control circuit (Figure 5) L. SW is an open/close switch that closes when the pedal is pressed forward; D. SW is an open/close switch that closes when the pedal is pressed after the pedal is depressed, and Re and SW are open/close switches that close when the operating rod 11 is pressed.

N. P is a detection switch provided in the needle position detection device 4, which detects the upper and lower positions of the needle separately and generates H level signals separately at each position, and in particular, the lower detection position is detected by each tip (not shown). This is the time when the needle thread loop is captured. C. T is a counter, N. An upper position signal is input from P and counted, and a binary code output is generated at the A-D output section. The outputs of A to D are input to 0R1 to 0R4 separately, and 0R1 to 0R4 are input to the previous U, V, W,
Signals from X are input separately. U. SW is a normally closed switch that opens when the lever 10 is rotated from the intermediate position to one side or the other; R is a reset circuit which generates an L output from the time the power is turned on until the first front pedal depression operation, and after the first pedal front depression operation becomes the H output, the output is held until the power is cut off. Ffl
The outputs of 0R1 to 0R4 are all H and the G7 output is L.
Therefore, when the clock input from 114 becomes H, Q
Output L. O output is set to H, and when the G8 output becomes H and the input from 115 becomes H, the respective outputs are inverted.

Ff2 uses the η output of Ffl as a clock input, and inverts its output every time a rising signal is input to its input. 0S1,
0S2 is a one-shot multivibrator, and when there is a trigger input, it generates an L output for a set time of ΔTl and ΔT2, respectively. In particular, ΔT2 is the time required for the needle to move up and down once when the sewing machine is driven at a predetermined low speed. do.

Re,SOL is a solenoid of the electromagnetic device 22, and Gl
8 becomes the H output, it is energized and the electromagnetic device is put into operation. T. SOL is a solenoid of an electromagnetic device associated with the thread tension regulator 24, and when 117 becomes an H output, it is energized to operate the electromagnetic device. S. C is an upper limit speed setting circuit that sets the driving speed of the electromagnetic clutch motor. Normally, the speed is controlled to be proportional to the amount of forward depression of the pedal, but when the transistor Tr2 is turned on, it is driven at a predetermined low speed. Control as follows. M. D is a drive control circuit for electrically driving or stopping the motor, which controls the motor so that it is driven when Gl9 becomes an output L, and stopped when it becomes an output H. Also U. S is a top stop command circuit which generates a command signal so that the sewing machine stops at the needle top position when G2O becomes the L output. The present invention has the above structure, and its operation will be explained next.

I Stitch count setting When the power is turned on from the state shown in Figures 4 and 5, the terminal ■
An H level voltage is applied to P.C, and in the needle setting circuit of FIG. An instantaneous signal is generated from S, transistor Trl becomes conductive, the set input of FFl becomes L, and F
The Fl output is set to L, and this L output sets G3 to H.

A. SW-I. D. SW is open. C(7)■～
■The output becomes H and MANU. SW is also open so G
The input to 1 becomes H, H, and the output becomes L. The H inverted by 11 becomes the G2 output, and G2 becomes L. Therefore, since G4 becomes H, G5 becomes an output H due to the instantaneous L input due to conduction of the transistor Trl, and immediately becomes an L output. B. G5 output as latch input j. R is G5
By the fall of the output to H, outputs L, which are inverted from the states of the A, B, C, and D inputs, are generated as 0a, 0b, 0c, and 0d. Therefore, when corner stitching is to be performed at this time, the number of stitches can be arbitrarily selected by operating the pedal. To set the number of stitches for corner stitching, press the needle selection button 12, for example, the four-stitch needle selection button, and press E. If SW is a closed circuit, D. The output of C(7)N,il,V,■ is H,H,
As a result, G2 becomes an H output. The H of G2 becomes the G4 input and 12 becomes the L output, and the 12 output is delayed by the capacitor C and then operates to become the G2 input and the reset input of FFl, making FFl an output H. Since lever 10 is in the intermediate position, U. SW (Figure 5)
is a closed circuit, the lead wire Y becomes H through 15, 16, and 120, and the G4 input is H<151 of Y, G2, and G3.
The delayed H of 2 causes an instantaneous L output, and G5
becomes an H output for a short time and then becomes an L output. By its fall, B. R is A, B, C, D input H, H
, L, H are inverted and the outputs L, L, H, L are ′Qa, ′Q
It is held as b, Oc, Od output. To change the number of stitches, use another needle selection button, for example the needle selection button 12 for three stitches.
Press C. When SW is closed, D. The output of C is L, L
, H, H, G2 becomes H output and G
4 is set to L output for a short time, the output of G5 becomes on L-H, and B. R is the output H, H, L, L obtained by inverting the L, L, H, H of the A, B, C, D inputs as 'Qa, Ob, -6c, 'Qd
occurs in Press the LOCK button 14 to set the pressed position to LOCK. When the SW is closed, 13 becomes H, the H of 13 and FF1 is input to G3, and the output becomes L, and G4 is held at the H output. ■U, ■, W,
, H, H are input.

When the lever 10 is rotated clockwise in FIG. 1 from the intermediate position, the needle bar 6a is held at rest by the pause mechanism 8 when it next rises to the upper position, and the cam plate 16 is rotated counterclockwise in FIG. The engaging portion 2 of the engaging body 19 rotates from the protrusion 15 to
0 is disengaged, and the engaging body 19 is rotated counterclockwise in FIG. 2 by the acting force of the coiled spring 18 to engage with the notch 21b of the cam plate 16, and the USW is opened. 15 is L. ．． l6 becomes H output, and Gll output is L along with GR<7) H output.
113 output to H.

16 H output becomes Gl3, Gl4, FF2 input, and G
l3 becomes L due to the H outputs of 16 and 13, causing the FF2 output to become L, and the Gl4 output to become H.

Since the FF2 output does not change unless the USW is opened and the 16 output does not become L, Gl4 is held at the H output. Push the pedal forward to operate the L. When SW is closed, 19 becomes an output H, and G19 becomes an output L, and M. D controls the motor to be in a driving state, and at this time, the 113 output is H, and U, V, W, and X are L, L, H, H, so G6
is H, and the G9 output is L, so the 116 output becomes H, making Tr2 conductive, and S. C controls the motor to drive at a predetermined low speed.

The main shaft of the sewing machine rotates and single needle stitching is performed using the needle bar 6b. A position signal H above P is generated and C. When the third upper position signal becomes the clock input, C.T becomes the clock input. T(7) A, B, C, D outputs are H, H,
Since it becomes L, L, 0R1 to 0R4 become H output, and G7
114 is set as an output L, and 114 is set as an output H, and the output of Ffl is inverted to become an output L and an output H. Q output L sets Gl2 to H
C. as output. Clear T, η output H inverts Ff2 output, sets Q output to H, and sets Gl7 to output L,
Continue pressing the pedal forward until the L. Even if SW is closed, Gl9 becomes H output and M. D stops the motor when the needle down position signal is generated. At this time, Gl2 has 113 H,
The O output H of ffl is input and the output is L, and C. Clear terminal of T is L input. And then C. N to the clock input of T
Even if the upper position signal is input from P, counting is not performed and A, B
, C, D outputs do not change. Turn the cloth around the needle 5b at a predetermined angle, and press the pedal forward again to move the cloth to the L. When SW is closed, 19 becomes H output and Gl5 instantaneously becomes L.
output, and G8 becomes H. ．． ll5 becomes L, resets Ffl, inverts its output, and changes the Q output to H. Set the output to L, set Gl7 to H output, and connect Gl9 with H of I9.
is the output L, M. D is S. The motor is controlled to be driven at a predetermined low speed set by C, and the sewing machine forms a seam at the outer corner with a single needle. N. The upper position signal from P is C. When the three upper position signals are input, that is, when the position corresponding to the inner corner is reached, 0R1 to 0R4 become the output H, G7 becomes the output L, and 114 becomes the output H. The output becomes H, inverting the output of Ffl, and the Q output becomes L. 'The Q output becomes H, and the O output becomes H, which causes the Q output of Ff2 to become L. Q of Ff2
Output L triggers 0S1 to produce L output for Δt1;
Re. with Gl8 as H. energizes SOL, electromagnetic device 22
Pull the plunger 23 to the right in FIG.
The cam plate 16 rotates clockwise in FIG. 2 against the force of the winding spring 18, and the cam plate 16 rotates clockwise in FIG. The engaging portion 20 is engaged and maintained. Therefore, the lever 10 also returns to the intermediate position and
．． When the SW is closed, the pause mechanism 8 also becomes inactive, and the needle bar 6a, which has been at rest, is linked to the main shaft and can move up and down in synchronization with the other needle bar 6b. Also during this time, transistor T
Since r2 is conductive, the motor drives at low speed, and US
When W becomes a closed circuit and the 113 output becomes L, Gl2 becomes H.
Clear CT as output, G9 becomes output H, and ■1
6 output becomes L, transistor Tr2 becomes non-conductive, SC cancels the predetermined low speed setting, and controls the speed so that the motor is driven at a speed corresponding to the amount of depression of the pedal. Therefore, the sewing machine shifts from single-needle sewing to double-needle sewing without stopping, forms stitches continuously, and performs double-needle sewing at a speed corresponding to the amount of depression of the pedal. In this embodiment, a regulation circuit that directly regulates the counter CT has been described, but a regulation circuit that regulates this by providing a switch circuit between the detection means NP and the counter CT may also be provided. good.

In addition, in this embodiment, the sewing machine is switched from the saw sewing state to the double needle sewing state by the action of an electromagnet when a predetermined number of corner stitches are completed, but the sewing machine may be stopped when the corner sewing is completed. It may also be carried out on objects. As described above, according to the present invention, the prime mover is driven in connection with the generation of the starting signal by the pedal operation after the operation signal is generated by the operation of the operation means 10, and the driving body is driven in connection with the generation of the count signal by the counting circuit CT. a control circuit for generating a signal for stopping the prime mover, driving the prime mover in connection with the generation of the next starting signal and activating the actuating means in connection with the generation of the count signal again; and generation of the first count signal. By providing a regulation circuit that cuts off the position signal to the counting circuit until the second start signal is generated in connection with After forming the seam and stopping, the position signal to the counting circuit is cut off until the sewing starts again to form the seam up to the position corresponding to the inner corner, so the operator may accidentally turn the main shaft of the sewing machine by hand. Even if the sewing machine is moved, the counting circuit does not count, and the sewing machine can be returned to double-needle sewing after the specified number of stitches are reliably formed to the position corresponding to the inside corner, or the sewing machine can be stopped. As a result, beautiful corner stitches can be reliably formed at the corners of the cloth, which has the effect of improving the quality of the product, and also has the effect of simplifying operations for the operator and improving work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the sewing machine main body of this embodiment, FIG. 2 is a front view of the locking mechanism of the operating means, and FIG. 3 is a perspective view of the locking mechanism.
Figure 4 is the stitch count setting circuit, Figure 5 is the sewing machine control circuit, and Figure 6 is the sewing machine control circuit.
The figure is a time chart of the stitch number setting circuit, and FIG. 7 is a time chart of the sewing machine control circuit. In the figure? W is the pedal, 10, USW is the operating means,
4, NP is a needle position detection means, CT is a counting means, or ReSOL, 22 is an actuation means, and Gl2, ll3, ff are regulation circuits.

Claims (1)

[Claims] 1. It is possible to perform double-needle stitching, in which stitches are formed using two needles that are arranged at a distance and intersecting each other in the cloth feeding direction, and single-needle stitching, in which stitches are formed with one of the needles inoperative. a driving body connected to the main shaft of the sewing machine, a petal that generates a start signal in connection with one-way operation from a neutral position, and a first position where the sewing machine performs single-needle sewing and generates an operation signal, and an operating means capable of moving and locking the remote sewing machine to a second position for double-needle sewing; and a needle position detecting means arranged in relation to the sewing machine main shaft to detect a predetermined rotation angle of the sewing machine main shaft and generate a position signal. , a counting circuit that closes in connection with the generation of the operation signal, counts the position signal, and generates a count signal when a predetermined number is counted, and a driving body in connection with the generation of the first starting signal after the operation signal is generated. a control circuit that drives the driving body, stops the prime mover in connection with the generation of the count signal, drives the prime mover in connection with the generation of the second start signal, and generates an actuation signal in connection with the generation of the count signal again; an actuating means actuated by an actuation signal to move the actuating means from a first position to a second position or to stop the prime mover; A corner stitch control device for a two-needle sewing machine, which is equipped with a regulation circuit that blocks a position signal to a counting circuit.