JPS5937992B2 - Sewing machine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for stopping the sewing machine at the needle down position in connection with releasing the pedal from the front pressing operation, and performing rear pressing operation of the pedal from the front pressing operation or releasing operation. In association with,
The present invention relates to a control device for a sewing machine that stops a needle at a predetermined position in a sewing machine that stops the sewing machine in an obliquely upward position and operates a thread cutting device at a predetermined rotation angle of the main shaft of the sewing machine.

In the prior art, means are known for selecting the stop position of the needle in relation to a pedal release operation to be in the upper or lower position. In a sewing machine that operates a thread trimming device to stop the needle in the upper position, or in a sewing machine that operates the thread trimmer after the needle has stopped in the upper position, the selection means for selecting the needle stop position is the needle down position. If the needle cannot be stopped at the upper position, the circuit of the needle stop position selection means must be disabled in connection with the pedal rear depression operation for thread trimming operation. I had to.

Further, the circuit of the needle stop position selection means is configured to be disabled in relation to the next front pedal depression operation.

Therefore, in the above-mentioned conventional device, even if the selection means is operated to select the downward position after the needle is stopped at the upper position by depressing the pedal later, the needle does not descend, and the needle drop position at the beginning of the first stitch is used. To make sure the thread is accurate, or when threading the looper on a chain stitch sewing machine, press the pedal slightly forward to drive the main shaft of the sewing machine for half a cycle, then lower the needle and stop it at the lower position. Alternatively, it is necessary to perform complicated operations such as turning off the power switch and rotating the pulley by hand to move the needle to the lower position, resulting in a disadvantage that work efficiency is significantly reduced.

The object of the present invention is to eliminate the above-mentioned drawbacks and improve work efficiency.

An embodiment of the present invention will be described with reference to the drawings. When a power switch (not shown) is turned on, a direct current obtained by rectifying and smoothing a power supply (alternating current) is supplied to a terminal VCC of the circuit as "logically 1./(hereinafter referred to as "Logically, ヮ is omitted and it is simply represented by 1 and 0)" is input as a signal.

1 to 33 are known IC Nando games (abbreviated as G).

The needle position detection device P detects the upper and lower positions of the needle and generates a detection signal 0.

LSW is a pedal switch that is always on to close the circuit, and turns off to open the circuit when the pedal is pressed forward, and TSW is a pedal switch that is turned on and closes when the pedal is pressed after the pedal.

The switch S1 is a selection switch disposed in an electrical box or the like, and is manually operated to select the stop position of the sewing machine to one of the upper and lower needle positions.

S2 is a reversing switch that is turned on by an operation of the knee or the like to close the sewing machine, and when turned on, the sewing machine stop position selected by the selection switch S1 is reversed and the sewing machine is stopped at the other position.

ff is a well-known J- master-slave flip-flop, and the terminal and CLEAR are always connected from the terminal Vcc to the J- terminal.
When a signal 1 is input to the terminal, the output becomes 1 and the output becomes 0.

Through the operation of S2, G1. Signal 0 is connected to CL via G2
When input to the OCK terminal, the times output and times output are inverted, times output becomes 0, times output becomes 1, and the next 0 signal becomes CLOC.
When the K input is input, it is further inverted and the output becomes 1 and 0, and when the Preset input changes from 1 to 0, the Preset
Q, the output is set to the initial state.

The output terminal is connected to the up side terminal of Sl, and the Q output terminal is connected to the down side terminal.

FF is a well-known flip-flop, and the output terminal of the preset circuit (Fig. 2) is connected to the terminal e. When the power is turned on, 0 is input and becomes the set input of FF1, and the output of FF1 is It becomes 0.

The output 0 of FF1 becomes a set input for FF2 and FF3, and stabilizes the initial operation of FF2 and FF3.

T is a well-known monomulti whose output is 0 and output is 1 for a predetermined period of time when trigger signal 1 is input to the B terminal,
It is assumed that T1 has a set time of Δt1, T2 has a set time of Δt2, and T3 has a set time of Δt3, and Δt1 and Δt2 satisfy the relationship Δ11>Δt2.

T1 constitutes a speed detection circuit that uses the upper position signal as a trigger signal to detect stoppage of the sewing machine with G27, and T2 constitutes a speed detection circuit that uses the lower position signal as a trigger signal and detects a predetermined low speed of the sewing machine with G28. .

That is, the pulse width of the upper signal or lower position is T1. Each set time Δt1 of T2. When it becomes longer than △t2, G
27 or G28 becomes 0, and this pulse width becomes △t1. △
When it is shorter than t2, T1. σ of T2 is cleared to 1
to return to.

Also, T3 does not have a clear terminal and when triggered, △t3
The output is set to 0 without opening.

Ry is a relay device that drives a low-speed motor, and M
, B is an electromagnetic device that brakes a low-speed motor, and M
, S is an electromagnetic device that activates the safety device, M.

T is an electromagnetic device that operates the thread cutting device, M and L are electromagnetic devices that operate the thread loosening device, and each device receives signal 1.
It is energized and activated when the signal is input, and is deactivated when the signal 0 is input.

For Ry, M, and B, when G16 becomes 0, G18 becomes 0,
When G19 becomes 1, it acts to stop the low-speed motor, and when 016 becomes 1, G18 and 1019 become 0, causing the low-speed motor to drive.

Also, for M, T, M, and L, G29 becomes 0 and G30 becomes 1.
When T3 is triggered, it is energized and operates for the set time Δt3 of T3.

The configuration of the present invention is as described above, and when the SL selects the lower position and connects to the down side terminal, and the power switch is turned on with the needle stopped at the lower position, FF1Q becomes 0, as described above. FF2Q becomes 0, FF3Q becomes 0, Q of ff becomes 1, Q becomes 0, and the circuit becomes stable (Fig. 3 1) By pressing the pedal forward, LSW turns off, G3 becomes 1, and G4 becomes 0. becomes 0, resets FF2, sets Q to 1, and sets Q to 0.

FF2Q's 1 sets G10 to 0, G12 to 1, and G13
becomes 0.

0 in G4 sets G16 to 1, energizes Ry and de-energizes MB to drive the low speed motor, and the sewing machine is driven at low speed.

By pressing the pedal harder, the clutch disengages the low speed motor and engages the high speed motor, driving the sewing machine at high speed 1.

When the pedal is released, the LSW is turned on and the clutch is again engaged with the low-speed motor, and the sewing machine is gradually decelerated to the driving speed of the low-speed motor.

When T or T2 detects the speed based on their respective position signals and G27 or G28 becomes 0, FF3 is reset and Q becomes 1.

G4 becomes 1, but the Q and output of FF2 do not change.

At this time, G12 is 1 and G13 is 0, so G15 is 1 when the lower position is detected, G16 is 1 of G24, and G15 is 1.
1, G4's 1, and G20's 1 are input, G16 becomes 0, the low speed motor is stopped, and the sewing machine stops at the needle down position.

From this state, when you step back on the pedal and turn on the TSW (Fig. 3 1i), G23 becomes 1, G20 becomes 0, and G16
is set to 1, the low speed motor is driven by 1, and the sewing machine is driven at low speed.

When the needle rises to the upper position, position signal 0 is input to G29 via G22, and G29 receives 1 of G22 and 1 of FF3Q.
, G23's 1 and FF2Q's 1 are input and G29 becomes 0, triggering T3 as described above and transmitting M-T and ML.
is energized, thread trimming is performed, and during this time T3's mutual 0
Therefore, G24 becomes 1, G25 becomes 0.26, and M-
8 is energized.

At the same time, FF2 is inverted due to 0 in T3Q, and Q becomes 0.
Both become 1, and Q output 0 makes G10 1 and G12 becomes 0.
, G13 becomes 1, and the needle is in the upper position, so G14 becomes 1.
So, G16 has 1 of G14, 1 of G20, and 1 of G4.
, 1 in G15 is input and G16 becomes 0, stopping the low speed motor and stopping the sewing machine at the needle up position.

From this state, if you press the pedal forward to turn off the LSW (
Figure 3 m) FF2 is reset, Q output becomes 1, Q output becomes 0, G10 becomes 0, G12 becomes 1, G13 becomes 0.
become.

Further, G16 becomes 1 due to G4 being 0, and as described above, the sewing machine is driven at low speed and then shifts to high speed driving.

When 82 is turned on while the sewing machine is running, G1. Signal 0 is input to the CLOCK input of ff via G2, and f
Invert fQ and the output of the calculation, and set (to 1 and Q to 0.

Since SL is not switched, the conventional 1 to 0 is input to the down side, G10 is set to 1, G12 is set to 0, and G13 is set to 1.
Set to 1.

When the pedal is released, the sewing machine decelerates to the low motor speed in the same way as described above, and when the needle up position is detected, G14 becomes 1 and G16 goes to 0, stopping the low speed motor and stopping the sewing machine at the needle up position.

But G29 is 1 and T3 is not triggered and M-T
is not energized.

From this state, if you press the pedal forward to turn off the LSW (
3), as the sewing machine is driven again, G7 instantaneously becomes 0, G8 becomes 1, and G9 becomes 0, becoming the P reset input of ff, and the Q and output of ff remain in their initial state, i.e. Both are 0 and Q is 1.

Therefore, the next time the pedal is released, the sewing machine will stop at the needle down position.

When the sewing machine is stopped and Sl is switched to the up side (Fig. 3 V), G10 and G11 both become 1, G12 becomes 0, G13 becomes 1, and since the needle is stopped at the down position, G14 becomes 0, G16 becomes 1, and the sewing machine is driven by the low speed motor.

When the needle rises to the upper position, G14 becomes 1 and G16 becomes 0.
Therefore, the sewing machine stops at the needle-up position, but G29 is 1 and M-T is not energized.

Next, when this Sl is switched to the up side and the pedal is pressed forward and then released (Fig. 3 ■), G14 becomes 1 at the needle up position and G16 becomes 0, as described above.
Stop the sewing machine at the needle up position.

At this time, the Q of FF3 is 1, and the TS is
When W is turned on (Fig. 3 ■), G29 becomes 0 and triggers T3, and as a result, G31 becomes 0 and thread trimming is performed, FF2 is reset, Q output becomes 0, and G20 becomes 0. 1, 016 is held at 0, the low speed motor is not driven, the sewing machine is stopped at the upper position, and M-
8, M-T.

Only M-L is energized to perform thread cutting.

Depress the pedal forward again to drive the sewing machine, and when S2 is turned on in the driving state (Fig. 3 ■), the ff CLOCK
is set to 0 and inverts the Q output.

That is, page becomes 1, Q becomes 0, GIO becomes 0, and G11 becomes 1.

G12 becomes 1, G13 becomes 0, and when the pedal is released, G15 becomes 1 at the needle down position, G16 becomes 0, and the sewing machine is stopped at the needle down position.

When the pedal is pressed backward from this state (Fig. 3 IX)
TSW is turned on, G23 becomes 1, G20 becomes 0, G16 becomes 1, and the sewing machine is driven at low speed.

FF3Q in G29 when detecting needle top position. FF2Q, G2
3. 1 of G22 is input and becomes 0, triggering T3 and energizing M-T and M-L, and FF2 is set due to the immersion force of T3 being 0, making q output 1 and Q output 0, and G
8 is set to 1 and G9 is set to 0 to become the preset input of ff, and the output of ff is returned to the initial state of Q output 0 and Q output 1.

Therefore, G10゜G11 are both 1, G12 is 0, and G1
3 becomes 1 and when the needle top position is detected, G14 becomes 1 and G
16 to 0 and the sewing machine stops at the needle-up position.

Even after switching SL to down after stopping, G10. G11 remains at 1, and I press the pedal again to switch to TS.
Even if W is turned on, G20 remains 1 and G16 remains 0, and the sewing machine does not drive. G29 receives 0 from FF2Q and remains 1, and thread trimming is not performed.

82 after thread trimming and stopping at the upper position by pressing the rear pedal
When (X in Figure 3) is operated, ff is generated via Gl and G2.
Calculate by inputting 0 to CLOCK, Q output is 1, respectively.
Flip to 0.

At this time, since FF2Q is 0, G10 is 1, and because FF2Q and ffQ are 1, G11 becomes 0, so G1
2 becomes 1, G13 becomes 0, G14 becomes 1, G15 becomes 0, G16 becomes 1, the sewing machine is driven at low speed, and when the needle down position is detected, G15 becomes 1 and G16 becomes 0, and the sewing machine moves to the needle position. Stops in the lower position.

Further operating S2 (Fig. 3 XI) will result in the CLOC of ff
0 is input to K, the Q and Q outputs are returned to their original states of 0 and 1, and the needle is raised to the upper position in the same manner as above.

The inversion of the output of ff due to the operation of S2 returns to the initial state when 0 of G9 becomes the Preset input due to the pedal operation.

Next, select SL to the lower position, release the pedal from the high-speed driving state, and then press the LSW.
is turned on and the TSW is turned on almost simultaneously, the sewing machine gradually decelerates to the driving speed of the low-speed motor, triggers T2 with a lower position detection signal at a predetermined low speed, and turns on G after △t2.
27 is set to 0, and FF3Q is set to 1.

Even if the needle reaches the lower position and G15 is set to 1, the TSW is still on, so G20 becomes 0 and G16 remains 1.
The sewing machine continues to be driven.

When the needle detects the upper position, G29 becomes 0, T3 is triggered and the thread trimming device is activated by Q output 1, and T
Set FF2 by Q output 0 of 3, and set FF Pres
Enter 0 to the et input to set G12 to 0, and set G13 and G
15 is set to 1, these logical operations are performed in the upper position detection range, and G14 becomes 1 and the hand stops at the upper position.

As described above, according to the present invention, by operating the selection switch S1, the needle of the sewing machine can be stopped in either the upper or lower position when the pedal is released, and by operating the reversing switch S2, the needle can be stopped in the backward position. Operates the thread trimming device by pressing the foot to stop the needle in the upper position, then rotates the main shaft of the sewing machine by half a cycle to stop the needle in the lower position, ensuring accurate needle drop position at the start of sewing. It simplifies work, and also makes it easier to thread the thread through the looper in a chain stitch sewing machine, thereby improving work efficiency.

In addition to sewing machines that operate the thread trimming device after the needle has stopped at the upper position as in this embodiment, there are also sewing machines that operate the thread trimming device while the needle is rising from the lower position to the upper position. It is clear that a similar effect can be obtained when working to accurately determine the position of the drop.

[Brief explanation of the drawing]

FIG. 1 shows a control circuit of this embodiment in a state where the pedal is depressed forward, FIG. 2 shows a preset circuit, and FIG. 3 shows a time chart corresponding to a needle stroke. In the figure, Sl is a scheduled stop position selection means, and S2 is a needle position changing means.

Claims (1)

[Scope of Claims] 1. A pedal that is related to the motor of the sewing machine and enables forward and rear pedal operations, and an upper position signal or a pedal that is synchronized with the rotation angle of the sewing machine main shaft corresponding to the needle up position or needle down position. a detection means that separately generates a lower position signal; a thread trimming means that can operate before or after the sewing machine spindle stops at the needle upper position; a selection means for generating a different setting signal to select one of the lower positions; and a selection means for driving the sewing machine by a front depression operation of the pedal and generating an upper position signal or a lower position signal according to a setting signal of the selection means in connection with release of the front pedal operation. The sewing machine is stopped by the signal, the selection means is disabled in relation to the rear pedal operation, the sewing machine is stopped by the upper position signal, and the thread trimming means is activated before or after the stop, and then the pedal is operated by the front pedal. a control means for activating the selection means by controlling the selection means, and a control means for operating the selection means and the control means in connection with a manual operation after the pedal is rear-depressed to drive the sewing machine in response to the next lower position signal; A sewing machine control device provided with needle position changing means S2 for stopping the sewing machine.