JPS6366548B2 - - Google Patents

Description

[Detailed description of the invention]

In accordance with the sewing machine speed command signal according to the movement amount S of the sewing machine pedal from the reference position,
This relates to a sewing machine drive device that starts, stops, and controls the speed of the sewing machine. Conventionally, as a sewing machine drive device, the sewing machine is rotated by a depression amount of S ₁ from the reference position of the sewing machine pedal, and the sewing machine is driven half a needle at low speed by a depression amount of S ₂ from the reference position. Although various starting methods have been adopted, the starting position on the depressing side corresponding to the above-mentioned depressing amount S ₁ and the starting position on the depressing side corresponding to the depressing amount S ₂ have generally been configured so that they cannot be easily changed. . In other words, the method for detecting the amount of depression _S1 and the amount of depressing _S2 from the reference position of the sewing machine pedal is to convert the linear movement of the sewing machine pedal into rotational movement using a lever, and to use the movement of the lever to trigger a fixed micro switch. A method of turning on and off the light, or a method of fixing a shielding plate with a partial notch on the lever and using the shielding plate to switch a fixed optical sensor with a pair of light emitting and light receiving elements has been adopted. When changing the starting position corresponding to the amount of depression S ₁ or the starting position corresponding to the amount of pressing back S ₂ , it is necessary to change the fixing position or shape of the micro switch in the former case and the shield plate in the latter case. This is extremely difficult, and even if a sewing worker tries to adjust the position to improve sewing efficiency, it is practically impossible. The present invention eliminates the above-mentioned drawbacks of the conventional technology, and allows sewing workers to easily adjust the starting position corresponding to the above-mentioned depression amount S ₁ or depressing back amount S ₂ , so that sewing workers can adjust the starting position suitable for each person in order to improve sewing efficiency. It is an object of the present invention to provide a sewing machine driving device that can be used relatively easily when selecting a sewing machine. FIG. 1 shows the structure of the present invention in blocks, and the structure will be explained below based on the drawings. 1
has a lever mechanism that converts the linear movement position of the sewing machine pedal (not shown) into a rotational position,
The lever has a built-in magnet. Reference numeral 2 denotes speed command setting means, which comprises a lever position detection circuit 3 and an A/D converter 4, and the lever position detection circuit 3 includes a magnetic resistance element, etc., in which the rotational positions of the magnets built in the lever are opposed to each other. This is a circuit for detecting with a magnetic sensor and converting it into an electrical signal S _A.
Further, the A/D converter 4 is a converter for converting the electrical signal S _A , which is a continuous quantity, into a digital signal S _D , and the specific configuration of each will be described later. 5 is a switch element consisting of several selection switches for selecting the starting position; 6 is a ROM;
It is a control means consisting of a one-chip microcomputer (hereinafter referred to as microcomputer) that has built-in RAM and I/O and serves as the main body of control. Reference numerals 7 and 8 indicate drivers for a clutch coil 10 and a brake coil 11, respectively, which are built into a motor 9, and the motor 9 has a main body that constantly operates at high speed;
It consists of an electromagnetic clutch/brake section configured to transmit the rotational force of the motor to the output shaft through the magnetic circuit by excitation of the clutch and brake coil, and the rotational force of the motor 9 is transmitted to the sewing machine 12 via the belt. Ru. Reference numeral 13 denotes a needle position detector attached to the shaft end of the sewing machine 12. The needle position detector 13 is a needle position detector that is attached to the shaft end of the sewing machine 12.
A needle position signal (for example, a needle up position signal (N _u corresponding to the needle up position) and a needle down position signal N _D corresponding to the needle down position) is generated corresponding to the needle position of the sewing machine 12. 15 is a waveform shaping circuit for shaping the signal from the speed generator 14 and outputting a pulse signal _FG , which is composed of a Schmitt trigger circuit. The operation configured as described above is performed as follows. First, when the sewing machine pedal is depressed from the reference position, the built-in lever of the lever mechanism 1 is displaced _S
The lever position detection circuit 3 converts the displacement S _X into an electrical signal and outputs an analog signal S _A. This analog signal S _A is sent to the A/D converter 4
The signal is converted into a digital signal S _D and input to the microcomputer 6. The microcomputer 6 controls the clutch coil 1 through the driver 7 when the digital signal S _D reaches the specified value _S1 selected by the switch element 5.
0 is excited, the output shaft of the motor 9 is accelerated, and the sewing machine 12 is accelerated via the belt. This sewing machine 1
The speed of No. 2 is detected by the speed generator 14, and after being waveform-shaped into a pulse actual speed signal F _G by the waveform shaping circuit 15, it is output to the microcomputer 6, and the microcomputer 6 inputs the actual speed signal F _G into the digital setting. When the speed exceeds the speed set by the signal S _D , the brake coil 11 is excited via the driver 8, acting to rapidly decelerate the sewing machine 12, and the normal stable state depends on the magnitude of the excitation current of the clutch coil 10. Controls are in place to ensure that the results are obtained. When the digital setting signal S _D becomes smaller than the specified value S ₁ , the microcomputer 6 first controls the sewing machine 1.
After setting the low speed for positioning in step 2 and reaching a lower speed, when the needle down position signal N _D from the needle position detector 13 is detected, the brake coil 11 is excited through the driver 8, and the sewing machine 12 to stop at the predetermined needle down position. When the sewing machine pedal is pressed back in the opposite direction from the above-mentioned stopped state, the digital setting signal S _D corresponding to the position of the sewing machine pedal is output as described above, and the digital setting signal S _D is output to the switch. When the specified value _S2 selected by element 5 is reached, the microcomputer 6 first sets a low speed for positioning, drives the sewing machine 12 at a low speed, and then detects the needle from the needle position detector 13. Stop when the upper position signal is detected. As mentioned above, the drive/stop command is determined based on whether the digital setting signal S _D exceeds the specified value _S1 selected by the switch element 5, or from the needle down position due to the digital setting signal S _D reaching the specified value S2 or less. A command to half-drive the needle to move it to the needle-up position is issued. Here, the operation of the speed command setting means 2 and switch element 5, which constitute the input section to the microcomputer 6, will be explained with reference to FIG. explain. In the figure, reference numeral 16 denotes a bridge type magnetoresistive element, and when a constant excitation current is applied from the DC power supply Vcc through the resistor _R1 , its output voltage V _e changes depending on the rotational displacement S _X of the lever. Change. resistance
R ₂ to R ₅ and an operational amplifier IC ₁ form a differential amplifier circuit, differentially amplify the output signal V _e , and output a signal _SA . IC ₂ is the A/D converter 4, and its operation begins with the “H” level of the STC signal from the microcomputer 6.
Due to the transition from the state to the "L" state, the signal S _A
When the conversion to the digital value is completed, the A/D converter IC ₂ sets the converted data and changes the EOC signal from "H" to "L", and the microcomputer 6 The A/D conversion data S _D is inputted by the change of the EOC signal to "L". If, for example, a 5-bit one is used as the above A/D converter IC ₂ , the pedal depression position
The relationship of the converted data S _D to _S The reference position of the sewing machine pedal is A/D converted, and the converted data S _D becomes "9" in FIG. 3. On the other hand, the switch element 5 includes switches S _D0 , S _D1 , switches S _u0 , S _u1 and their respective pull-up resistors R ₆ to
It consists of _R9 and is input to the microcomputer 6. The switches S _D0 and S _D1 are on the pedal depression side,
In addition, the switches S _u0 and S _u1 are switches for selecting respective starting positions for the movement of the pedal to the side where the pedal is pressed back, and in this example, two of each are used, so there are four types of each. selection becomes possible. That is, the microcomputer 6 first converts the conversion data S _D into a value corresponding to the conversion data SD and indicating the starting position of the sewing machine as shown in Tables 1 and 2 using the built-in ROM table according to the selection of the switch group.

【table】

[Table] Furthermore, the microcomputer 6 compares the data S _D after A/D conversion as described above with the data D _RD or D _Ru obtained by converting the switch input using the built-in ROM table. If the data S _D is, for example, greater than the data D _RD , the sewing machine is driven at a speed corresponding to the position of the pedal, and the sewing machine is operated at the set speed. If the data S D is less than the data D _Ru , the sewing machine is started as described above. The operation is performed so that the needle is driven halfway up to the needle-up position. The above operation is shown in FIG. In the figure, solid lines indicate a state in which all the switches are off. That is, a state in which the data D _RD =15 and the data D _Ru =3 is shown. In addition,
By selecting the switch, four starting positions can be selected for both the depression side and the return side, as shown by the broken lines. As described above, the starting position S ₁ on the depressing side of the sewing machine pedal is selected in four steps by the switches S _D0 and S _D1 , and the starting position S ₂ on the depressing side is selected in four steps by the switches S _u0 and S _u1 . However,
By increasing the A/D converted data S _D to more than 5 bits and using a large number of switches, finer selections can be made, and the present invention is even more effective. As is clear from the above, the present invention
The starting position _S1 on the depressing side corresponding to depressing in the depressing direction from the reference position of the sewing machine pedal or the starting position _S2 on the depressing side corresponding to depressing in the depressing direction from the reference position of the sewing machine pedal can be selected by a switch element. If the switch is configured with a rotary switch or a digital switch, the starting positions S ₁ and S ₂ can be easily adjusted. Therefore, for example, a sewing worker can adjust the starting positions S ₁ and S ₂ to suit his or her needs.
can be adjusted very easily, sewing efficiency is improved, and the effect is great.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the sewing machine driving device of the present invention, Fig. 2 is a circuit diagram showing the specific configuration of the device, and Fig. 3 is an explanatory diagram showing an example of A/D conversion data for the pedal depression position in the device. , FIG. 4 is an explanatory diagram showing a configuration example of the sewing machine speed with respect to the pedal depression position. 1... Lever mechanism, 2... Speed command setting means,
3... Lever position detection circuit, 4... A/D converter, 5... Switch element, 6... Control means (microcomputer), 9... Motor, 12... Sewing machine, 13...
...Needle position detector, 14...Speed generator.

Claims (1)

[Claims] 1. A motor that drives a sewing machine, a control means that controls the motor at variable speed, a lever mechanism that is mechanically connected to a sewing machine pedal, and a mechanical movement of the lever mechanism that converts the amount of mechanical movement of the lever mechanism into an electrical signal. The control means comprises a speed command setting means for converting and commanding the speed of the sewing machine, and a switch element comprising a plurality of switches for defining a starting position of the sewing machine corresponding to movement of the sewing machine pedal, and the control means is configured to control the speed of the sewing machine. The sewing machine is commanded to stop at the speed command value S corresponding to a reference position, and the sewing machine is started at a speed command value S corresponding to a position where the sewing machine pedal is moved by a specific amount from the reference position in a specified direction. A sewing machine driving device in which the speed command value S can be selected by the switch element. 2. The sewing machine drive device according to claim 1, wherein the prescribed direction is the direction in which the sewing machine pedal is depressed. 3. The sewing machine drive device according to claim 1, wherein the prescribed direction is a direction in which the sewing machine pedal is pressed back. 4. The sewing machine driving device according to claim 1, wherein the speed command setting means includes an A/D converter, and the A/D converter converts the electric signal into a digital signal and outputs the digital signal.