JP2614928B2 - Sewing machine stop control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sewing machine stop control device using a spring clutch mechanism.

[Prior art] A conventional sewing machine stop control device uses a spring clutch mechanism for a connection portion between a main shaft and a motor, and performs operations from the separation of the connection portion between the main shaft and the motor to reconnection at a timing. (See Japanese Patent Publication No. 63-53563). 6 and 7 show the construction of a spring clutch mechanism used in a conventional sewing machine stop control device. A driving body 2 and a driven body 3 are fitted adjacent to a main shaft 1, and the driving body 2 is a motor ( (Not shown)
A pulley 4 connected by a belt or the like is fixed to the shaft, and the driven body 3 is fixed to a main shaft. Further, a spring 5 is fitted around a part of the driving body 2 and the driven body 3, an engaging body 6 is fitted around the spring 5, and one end of the spring 5 is fixed to the driven body 3 and the other end thereof. Are fixed to the engagement body 6. The driving body 2, the driven body 3, the spring 5, and the engaging body 6 form a spring clutch mechanism. This engaging body 6 has an engaging step 6a.
Is formed on the engaging step 6a.
7a is engaged. Further, a spring 8 is connected to the locking portion 7a of the locking body 7, and the locking portion 7a is urged away from the engaging step 6a of the engaging body 6. The locking body 7 is rotatably mounted on a rotation shaft 9 provided substantially at the center, and a stop solenoid 10 is mounted on the other end of the locking body 7.

Next, referring to FIG. 8, in the conventional sewing machine stop control device, the output of the switch circuit 11 is connected to the CK terminal of the flip-flop 13 via the inverter 12 and to the one terminal of the NAND gate 14. The rotation signal a of the motor is input to the other terminal of the NAND gate 14. One terminal of a NAND gate 15 is connected to the Q terminal of the flip-flop 13, and a detection circuit 16 provided in a position detection device arranged in relation to the main shaft 1 is connected to the other terminal. Output terminals of the NAND gates 14 and 15 are connected to the S terminal and the R terminal of the flip-flop 17, respectively. The input terminal of the one-shot multi 18 and 19 is connected to the Q terminal of the flip-flop 17, the output terminal of the one-shot multi 18 is connected to the drive circuit 20 of the stop solenoid 10, and the output of the one-shot multi 19 is controlled by the motor. Circuit 21
It is connected to the.

In this circuit, as shown in FIG. 9A, a high level start signal b and a low level stop signal c each time an operation member (not shown) provided on the sewing machine frame is operated as shown in FIG.
Occur alternately. Further, as shown in FIG. 9 (b), when the detection circuit 16 detects the rotation angle position of the main shaft 1 different from the step 6a of the engagement body 6, it generates a high-level position signal c.
The flip-flop 13 alternately switches the output of the Q terminal every time a low level input is input from the inverter 12 to the CK terminal as shown in FIG. 9 (c). As shown in (1), it is set when a low level is input to the S terminal and outputs a high level to the Q terminal, and when a low level is input to the R terminal, it is reset and a low level is output from the Q terminal. The one-shot multi 18 is used as a timer as shown in FIG. 9 (f), and the one-shot multi 19 is used for delay as shown in FIG. 9 (g). A high level signal is output for a predetermined time in response to the falling signal of the Q terminal output. The set time Δt ₁ > Δt ₂ , and Δt ₂ is set to a time sufficient for the main shaft 1 to make one rotation at a low speed.
Further, as shown in FIG. 9 (h), the motor control circuit 21 activates the motor by the activation signal b of the switch circuit 11, and responds to the falling signal of the output of the one-shot multi 19 after the generation of the stop signal c. Turn off the motor.

In the conventional sewing machine stop control device configured as described above, the output of the Q terminal of the flip-flop 13 becomes low while the sewing machine is being driven, and the flip-flop 17
Output of the Q terminal becomes high level, and the motor rotation signal a
Is at a low level and the NAND gate 14 is open. In this state, when the operation member is operated and the stop signal b is generated from the switch circuit 11, the output of the Q terminal of the flip-flop 13 goes high, and the NAND gate 15 goes low by the subsequent stop signal b, and the flip-flop 13 17 is reset, and the output of the Q terminal is set to a low level. One-shot multi 18, 19 by the falling signal of Q terminal
Is triggered, and a high-level output is generated at times Δt ₁ and Δt ₂ , respectively, and an energizing current is supplied from the drive circuit 20 to the stop solenoid 10 at time Δt ₁ . Accordingly, the stop solenoid 10 attracts the locking body 7 to the operating position, and the locking portion 7a of the locking body 7 engages with the engaging portion 6a of the engaging body 6.
Since the motor 21 is operated until the passage of Δt ₂ , the sewing machine main shaft 1 continues to rotate until the engaging portion 7a engages with the step portion 6a while moving along the path of the step portion 6a of the engaging body 6. When the engaging portion 7a engages with the step portion 6a, the spring 5 is opened by the engagement of the engaging body 6, so that the tightening of the spring 5 on the driving body 2 and the driven body 3 is loosened, and the driving body 2 and the driven body 2 are driven. The body 3 is shut off. At this time, the driven body 3 and the main shaft 1 continue to rotate slightly and stop, but the driving body 2 continues to be rotated by the motor via the pulley 4. After a lapse of time Δt ₂ during which the main shaft 1 can make one rotation, the control circuit 21 stops the motor when the output of the one-shot multi 19 falls. Further, by engaging portion 7a between the output signals Delta] t ₂ of the one-shot multivibrator 20 after the elapse of time Delta] t ₂ is stepped portion 6a and engage the engaging body 6, prevents acting blindly by inertia of the motor, one When the drive circuit 20 interrupts the drive current after the elapse of the output time Δt ₁ of the shot multi 18 and stops the operation of the solenoid 10, the locking portion 7 a returns to the original position by the spring 8. Therefore, the main shaft 1 can be rotated by hand.

[Problem to be Solved by the Invention] However, in this conventional sewing machine stop control device, when the main shaft 1 and the pulley 4 as the motor connecting portion are reconnected, the drive signal from the drive circuit 21 to the solenoid 10 is turned off. By this, the locking portion 7a of the locking body 7 is
The rotation of the motor can be transmitted to the main shaft, but even if the drive signal to the solenoid 10 is turned off, the time required for the locking body 7 to move to the original position by the spring 8 Therefore, if the motor is started before the locking portion 7a of the locking member 7 returns to the disconnection position, there is a possibility that a disconnection failure of the locking member 7 may occur.

The present invention provides a stop control device for a sewing machine that prevents a spring clutch mechanism from being disengaged by controlling a locking member in consideration of a time when a spring clutch mechanism is disengaged after confirming stoppage of a motor. It is intended to provide.

Means for Solving the Problems In order to achieve the above object, the present invention locks an engaging step of a clutch mechanism fitted to a main shaft by turning on / off a current supplied to a stop solenoid. In a sewing machine in which a body is separated or engaged with the engagement step portion to transmit or separate the rotation of the motor from the coupling portion of the motor to the main shaft, a switch of a speed controller is turned off during rotation of the motor. Means for supplying a current to the stop solenoid by detecting a signal of a predetermined phase from the spindle phase detection device, and a drive signal of the motor after a lapse of a predetermined time from the signal of the predetermined phase of the spindle phase detection device. Means for turning off, and when a rotation signal from a motor rotation detector that outputs a signal when the motor is rotating is not output for a predetermined time, the current to the stop solenoid is reduced. Off means.

According to the present invention, when the switch of the speed controller is turned off during the rotation of the motor, a signal of a predetermined phase is detected from the spindle phase detection device to supply a current to the stop solenoid, and the spindle phase detection is performed. The drive signal of the motor is turned off after a lapse of a predetermined time from a signal of a predetermined phase of the device, and when the rotation signal from the motor rotation detector is not output for a certain time, the current to the stop solenoid is turned off to stop the motor. The locking portion of the locking body operated by the solenoid is completely separated from the step of the engaging portion of the spring-type clutch mechanism.

[Embodiment] Referring to FIG. 1, in a sewing machine stop control device according to an embodiment of the present invention, a speed controller 23 and a spindle position detecting device 24 are connected to an input side of a control device 22. The stop solenoid 10 of the above-described conventional spring-type clutch mechanism is connected to the output side via a stop solenoid drive 25.
Is connected, and further, the motor
27 is connected. Then, a motor rotation detector 28 is attached to the motor 27, and a rotation signal of the motor 27 is input from the motor rotation detector 28 to the control device 22.

In this configuration, the speed controller 23 is a step-down type, sends out a signal SC to the control device 22, and a switch inside is off and a signal SC has a voltage of 0 V from a position where no step is taken to a predetermined step-in position. When the pedal is further depressed, the internal switch is turned on, and the signal SC is set to a predetermined value (for example, 2v to 5v) according to the depressed amount.
Is changed by The control device 22 is constituted by a combination of logics or a microcomputer. The motor control device 26 adjusts the amount of current supplied to the motor according to the motor control signal MDR from the control device 22, and is constituted by a current network such as a transistor and an FET. The spindle position detecting device 24 is arranged in relation to the spindle, outputs a high level from a phase of one spindle, and a signal SYNC which changes from another phase to a low level.
Is output. The drive device 25 adjusts the current supplied to the stop solenoid 10, and the drive signal STSO from the control device 22
When L is at a high level, the stop solenoid 10 is activated, and when L is at a low level, the stop solenoid 10 is deactivated. The motor rotation detector 28 interposes a disk provided with a slit between the optical sensors, and generates a low-level or high-level motor pulse signal MP by blocking light by rotating the disk. While the motor pulse signal MP is outputting a low level and a high level alternately, the control device 22
It is determined that the motor 27 is rotating, and if it does not change at either the low level or the high level, the control device 22 determines that the motor 27 is stopped.

Next, the operation of this embodiment will be described with reference to the time chart of FIG. 2 and the flowchart of FIG. First, when the switch of the speed controller 23 is turned off from on during the rotation of the sewing machine, the voltage of the signal SC {FIG. 2 (a)} becomes 0 V, and the control device 22 determines this and controls the stop of the sewing machine. Is started (step 1). Here, the control device 22 issues a low-speed command with the signal MDR {FIG. 2 (e)} to the motor control device 26, so that the motor control device 26 rotates the motor 27 to a predetermined low-speed rotation (for example, 200 spm). To limit the supply current of the motor 27 so that the motor 27 starts to decelerate (step 2). Then, the control device 22 determines whether or not the signal SYNC from the spindle position detecting device 24 (FIG. 2 (d)) has fallen at the beginning (step 3). When the fall (t ₀ ) has occurred, The control device 22 recognizes this. The drive signal ST of the stop solenoid 10 is generated by this signal SYNC.
SOL {Fig. 2 (f)} is output at a high level.
The stop solenoid driving device 25 to which OL has been input supplies a current to the stop solenoid 10 (step 4). After a predetermined time Δt ₁ after the signal STSOL becomes high level (step 5),
That is, the signal MDR {FIG. 2 (e)} after the guarantee time until the stop solenoid 10 is operated and the locking portion 7a of the locking body 7 in the above-described conventional example is engaged with the step 6a of the engaging body 6. Is set to a low level, the spring clutch mechanism separates the main shaft 1 and the motor unit, and the sewing machine stops at the lower position.
27 goes to a stop (step 6). The signal MP from the motor rotation detector 28 monitoring the rotation of the motor 27
The controller 22 determines whether or not the level in FIG. 7C has not changed for a predetermined time (Δt ₂ ) (step 7).
When the rotational speed of the motor 27 (FIG. 2 (b)) does not change, the control device 22 determines that the motor 27 is stopped (step 8). At this time (t ₃ ), by outputting a low level to the solenoid drive signal 25 by the signal STSOL (step 9), the stop solenoid 10 is turned off, and the main shaft and the motor unit are connected.

The present invention recognizes the stop of the motor 27 and reconnects the spring-type clutch mechanism in this manner, so that the control follows the torque and speed of the sewing machine at the time of stop control, and the next operation after the sewing machine stops smoothly. Work efficiency is improved.

Referring also to the flow chart of the time chart and the fifth view of FIG. 4, in other embodiments of the present invention, after step 9 of FIG. 5, at time t ₃ signal STSOL {FIG. 2 (f) No other operations are accepted for a certain period of time Δt ₄ after｝ is set to the low level, that is, until the guaranteed time from when the signal STSOL becomes low to when the spring-type clutch mechanism is completely disengaged has elapsed. (Step 10). Then, from t ₄ when the guarantee time has elapsed to allow start the next operation.

According to the present invention, in this manner, when a continuous operation of another operation of the sewing machine is performed, each operation can be reliably performed, and then the next operation can be performed.

[Effects of the Invention] Since the present invention is configured as described above, the sewing machine is turned off by turning off the spring-type clutch mechanism after detecting that the motor is securely stopped, and reconnecting the main shaft and the motor unit. Control following the sewing machine torque and sewing machine speed at the time of stop control, the next operation after the sewing machine stops can be performed smoothly, and work efficiency is improved. In addition, there is an advantage that the next operation can be performed after each operation is reliably performed during a continuous operation of another operation of the sewing machine.

[Brief description of the drawings]

FIG. 1 is a block diagram of a stop control device for a sewing machine according to an embodiment of the present invention, FIG. 2 is a time chart for explaining the operation of the device in FIG. 1, and FIG. 3 is a diagram for explaining the operation of the device in FIG. FIG. 4 is a flowchart showing a first embodiment of the present invention in another embodiment.
5 is a time chart for explaining the operation of the apparatus shown in FIG. 5, FIG. 5 is a flowchart for explaining the operation of the apparatus shown in FIG. 1 in another embodiment of the present invention, FIG. 6 is a sectional view of a conventional spring-type clutch mechanism, FIG. 7 is a side view of a conventional sewing machine stop control device, FIG. 8 is a block diagram of a control device for operating the device of FIG. 6, and FIG. 9 is a waveform diagram of each part of the block of FIG. 22 ... Control device, 23 ... Speed controller, 24 ...
Spindle position detector, 25 ... Stop solenoid drive, 26
…… Motor control device, 27 …… Motor, 28 …… Motor rotation detector.

Claims (1)

(57) [Claims] An electric current supplied to a stop solenoid is turned on / off at an engaging step of a clutch mechanism fitted on a main shaft to separate / engage a locking body with the engaging step.
In a sewing machine in which the rotation of the motor is transmitted to or separated from the main shaft from a connection portion of the motor, a signal of a predetermined phase is detected from a main shaft phase detection device when a speed controller is turned off during rotation of the motor. Means for supplying a current to the stop solenoid, means for turning off the drive signal of the motor after a predetermined time elapses from a signal of a predetermined phase of the spindle phase detection device, and outputting a signal when the motor is rotating Means for turning off the current to the stop solenoid when a rotation signal is not output from the motor rotation detector for a certain period of time.