JPS6366549B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention performs stop/start control of a sewing machine in accordance with a stop command or a start command caused by movement of a sewing machine pedal, and allocates each divided section of the stop command range as a control command section for a fabric holding mechanism built into the sewing machine. The present invention relates to a sewing machine driving device that performs biasing/castrating control of the cloth pressing mechanism. Conventionally, as a sewing machine drive device, linear movement of the pedal is converted into rotational movement by a lever, a shielding plate with a partial notch is fixed on the lever, and the shielding plate allows the light emitting and light receiving elements to be connected to each other. A configuration has been adopted in which the start/stop command signal or the control command signal for the cloth presser mechanism is obtained by switching a pair of fixed optical sensors. On the other hand, generally, at least three signals are required: a start command signal in the direction in which the pedal is depressed, a start command signal in the direction in which the pedal is pressed back, and a control command signal for the cloth presser mechanism. Conventionally, three pairs of signals are required for these necessary signals. A shielding plate and a light-emitting/light-receiving element were required. In the conventional system configured as described above, a shielding plate is attached or removed in order to handle sewing machines that require a control command signal for the cloth presser mechanism or sewing machines that do not require a control command signal (sewing machines that do not have a built-in cloth presser mechanism). Once the settings have been set by the manufacturer, it is impossible for a sewing factory, for example, to adapt the settings to different sewing machine models. Moreover, the structure was complicated and expensive. Furthermore, in the conventional system, only one specific section of the stop range is used as a control command section for the cloth presser mechanism, and the entire stop command range is not used as a control command, and furthermore, as described above, Since it is impossible to switch between energizing and energizing the presser mechanism, it is impossible for the sewing manufacturer to switch between the sections in the stop command range depending on the type of sewing or the contents of the sewing work, and the sewing worker cannot switch between the sections in the stop command range depending on the type of sewing or the contents of the sewing work. It was still incomplete in its purpose of improving sexuality. SUMMARY OF THE INVENTION It is an object of the present invention to provide an inexpensive sewing machine driving device that eliminates the above-mentioned drawbacks, allows a sewing worker to easily select various control patterns for controlling the cloth presser mechanism, and which is inexpensive. FIG. 1 is a block diagram showing the basic configuration of the present invention. Reference numeral 1 indicates a lever mechanism, which has a mechanism for converting linear movement of a sewing machine pedal (not shown) into rotational movement by means of a lever. The lever has a built-in magnet. Reference numeral 2 denotes a speed command setting means, which is composed of a lever position detection circuit 3 and an A/D converter 4, and the lever position detection circuit 3 is a magnetic resistor in which the rotational position S _X of the magnet built in the lever is opposed. It is a circuit for detecting with a magnetic sensor such as an element and converting it into an electric signal S _A , and the A/D converter 4 converts the electric signal S
This is a converter for converting S _A 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, and 6 is a switch element consisting of several selection switches.
It is a control means consisting of a 1-chip microcomputer (hereinafter referred to as microcomputer) that has built-in ROM, RAM, and I/O and serves as the main body of control. Reference numerals 7 and 8 indicate drivers for the clutch coil 10 and the brake coil 11, respectively, which are built into the motor 9. The motor 9 has a motor body that constantly operates at high speed, and uses the rotational force of the motor body to excite the clutch and brake coils. The rotating force of the motor 9 is transmitted to the sewing machine 12 via a belt. Reference numeral 13 indicates a driver for a cloth presser solenoid 14 for driving a cloth presser mechanism built into the sewing machine 12. Reference numeral 15 denotes a needle position detector attached to the shaft end of the sewing machine 12, which detects a needle position signal (( For example, a needle up position signal corresponding to the needle up position
A needle down position signal N _D ) corresponding to the N _U position is generated. 16 is a speed generator that detects the speed of the sewing machine 12 and generates a frequency signal according to the speed; 17 is a waveform shaping circuit that shapes the signal from the speed generator 16 and outputs a pulse signal _FG ; , usually consists 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 neutral position, the lever incorporated in the lever mechanism 1 rotates by a displacement S _X , and the lever position detection circuit ₃ converts the displacement _S
Output. This analog signal S _A is converted into a digital signal S _D by the A/D converter 4 and then sent to the microcomputer 6
is input. The microcomputer 6 receives the digital signal S _D
When reaches a specified value _S1 , the clutch coil 10 is excited through the driver 7, the output shaft of the motor 9 is accelerated, and the sewing machine 12 is accelerated through the belt. The speed of the sewing machine 12 is detected by the speed generator 16, and after being waveform-shaped into a pulse actual speed signal _FG by the waveform shaping circuit 17, it is output to the microcomputer 6, and the microcomputer 6 converts the actual speed signal FG into the pulse actual speed signal _FG . When the speed exceeds the speed set by the digital setting signal S _D , the brake coil 11 is excited via the driver 8, acting to rapidly decelerate the sewing machine 12. In a normal stable state, the magnitude of the exciting current of the crack coil 10 is Control is performed so that it is obtained by. When the digital setting signal S _D becomes smaller than the specified value S ₁ , the microcomputer 6 first sets a low speed for positioning the sewing machine 12 , and after reaching a lower speed, the needle position detector 15 detects the needle. When the lower position signal N _D is detected, the brake coil 11 is excited through the driver 8 to stop the sewing machine 12 at a predetermined needle lower position. When the sewing machine pedal is depressed in the opposite direction from the above-mentioned stopped state, the digital setting signal corresponding to the position of the sewing machine pedal is output as described above.
S _D is output, and the digital setting signal S _D is set to the specified value.
If it reaches S ₂ or lower, the microcomputer 6 first sets a low speed for positioning, drives the sewing machine 12 at a low speed, and then detects the needle up position signal N _U from the needle position detector 15. Stop at that point. As described above, the sewing machine is driven/stopped or variable speed controlled, and the operation of the cloth presser mechanism is performed as follows while the sewing machine is stopped. That is, the pedal is slightly pressed back from the center position of the neutral position (hereinafter referred to as the reference position),
Digital setting signal S _D converted as described above
When becomes less than the specified value _S3 , the microcomputer 6 drives the cloth presser solenoid 14 via the driver 13,
Therefore, control is performed to raise the cloth pressing mechanism. From this state, the pedal is further depressed,
When the digital setting signal S _D reaches _S2 , the microcomputer 6
First, the fabric presser solenoid 14 is turned off, and after waiting for the predetermined time required for the fabric presser mechanism to descend, the sewing machine 12 is driven half a needle from the needle down position to the needle up position as described above, and then stopped. After that, the digital setting signal is controlled to raise the cloth presser mechanism even in the division range below _S2 . The above control operation is based on the setting of the switch element 5, and for example, when the setting is changed, the cloth presser mechanism is controlled as shown below. That is, when the pedal is at the reference position, the cloth presser mechanism rises, and when the pedal is pressed back from this state and the digital setting signal S _D reaches S ₃ , and furthermore when it reaches S ₂ . The same operation as described above is performed, but when the pedal is depressed from the reference position and the digital setting signal S _D reaches the specified value S ₄ or more, the microcomputer 6 activates the cloth presser solenoid 1.
4 is turned off, thus lowering the cloth presser mechanism.
From this state, when the pedal is further depressed and the digital setting signal S _D exceeds _S1 , the sewing machine is driven as described above. As described above, the microcomputer 6 divides the pedal position (neutral position) at which the sewing machine is commanded to stop into three categories, and determines the content of the control command (energizing or energizing) for the cloth presser mechanism by moving the pedal position to each category. is selected and switched according to the input from the switch element 5, and various control patterns of the cloth presser mechanism are selected based on the pedal operation, which constitutes an input section to the microcomputer 6. An example of a detailed circuit configuration of the speed command setting means 2 and the switch element 5 is shown in FIG. 2, and the operation thereof will be described in detail below with reference to the same figure. Reference numeral 18 denotes a prisge type magnetoresistive element whose output voltage Ve changes in accordance with the rotational displacement S _X of the lever when a constant excitation current is applied from the DC power source Vcc through the resistor R ₁ . Resistors R ₂ to R ₅ and operational amplifier IC ₁ form a differential amplifier circuit,
The output signal Ve is differentially amplified and a signal S _A is output. IC ₂ indicates an A/D converter, and its operation begins by converting the signal S _A from the microcomputer 6 from the "H" state to the "L" state, and then converting it into a digital value. When the A/D converter IC 2 completes the conversion, the A/D converter IC ₂ sets the converted data and changes the signal from "H" to "L", and the microcomputer 6 changes the signal to "L". /D conversion data S _D is input. 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 conversion 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. Furthermore, the relationship between the sewing machine speed and the pedal depression position when the pedal depression position is represented by the digital conversion data S _D is shown in FIG. 4, and the above-mentioned operation will be explained below with reference to the same figure. In FIG. 4, the specified values S ₁ to _{S 4} are each S ₁
= 15, S ₂ = 3, S ₃ = 5, S ₄ = 13, and the digital setting signal S _D is divided by the microcomputer 6 into sections A to E according to their functions. Of the above categories, E is a category in which the speed of the sewing machine is controlled, but A to D are categories that have a command function regarding control of the cloth presser mechanism as described above, and in each of these categories The command function is provided by two switches SW _P and 2 shown in Figure 2.
For example, the microcomputer 6 selects _the first
As shown in the table, four types can be selected.

[Table] In Table 1, the operation of mode is as described above, and mode also controls the cloth presser mechanism shown in the table. Of course, the above switches SW _P and SW ₁
By further adding , modes other than those shown above can be easily added, and the present invention is also effective for these modes. As is clear from the above description, the present invention classifies the digital control signal S _D into "A" to "E" according to function, and in particular divides the digital control signal S D into categories "B" to "D" for issuing a stop command to the sewing machine. The control command for the presser mechanism is operated as a classification, and the control function of the cloth presser mechanism of each category can be selected by a switch element. Therefore, even in a sewing factory, for example,
To enable a sewing worker to easily switch the control mode of the cloth presser mechanism by operating the switch in order to improve work efficiency according to the model of the sewing machine depending on whether or not the cloth presser mechanism is provided or according to the contents of the sewing work. This makes it possible to improve sewing efficiency, and its structure is simple and inexpensive, and its effects are extremely large.

[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 explanation showing an example of the structure of A/D conversion data for the pedal depression position in the device. FIG. 4 is an explanatory diagram showing an example of the structure 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, 14
...Paper presser solenoid, 15...Needle position detector,
16...Speed generator.

Claims (1)

[Claims] 1 A sewing machine having a presser foot mechanism including an electric drive means, a motor that drives the sewing machine, a control means that controls the motor and the presser mechanism, a lever mechanism mechanically connected to a sewing machine pedal, It consists of a speed command means including an A/D converter that converts the mechanical momentum of the lever mechanism into an electric signal, and a switch element connected to the input end of the control means, and the speed command means is controlled by the electric signal from the speed command setting means. , the control means commands the sewing machine to stop when the lever mechanism is at a predetermined position, and commands the sewing machine to start when the lever mechanism moves away from the predetermined position, and divides the predetermined position into a plurality of sections, and divides the predetermined position into at least one section. The sewing machine drive device is configured to energize the electric drive means in a range, and to select between energization or deactivation of the electric drive means in other divided ranges by setting the switch element.