JPS6244960B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an abnormality warning device for notifying a worker of abnormalities in a sewing machine.

Prior Art When various abnormal conditions occur in a sewing machine, such as locking of the drive motor, incorrect needle hole selection, thread breakage, or incorrect operation of the start/stop button when using the foot controller, the operator notices this. Failure to do so may cause more serious malfunctions and endanger your work. Therefore, when an abnormality occurs, it is desirable to notify the operator as reliably as possible so that necessary measures such as inspection and repair can be taken at an early stage.

For this reason, it has been conventional practice to provide an abnormality warning lamp in the sewing machine and to notify the operator of the occurrence of an abnormality by lighting or blinking the lamp. However, this method of displaying an abnormality signal by lighting does not allow the worker to use the lighting even if the lighting display indicating the occurrence of an abnormality occurs, especially during sewing work where the attention is concentrated on the seam forming part. The disadvantage was that it was difficult to notify the occurrence of an abnormality because it could not be seen within the field of view. It is undesirable to impose a duty on sewing workers to constantly pay attention to an abnormality alarm indicator because it may increase the burden on the workers, leading to a decrease in the quality of the sewing work and increased fatigue.

On the other hand, if an alarm sound generator such as an alarm buzzer is installed together with an abnormality alarm lamp, and an alarm sound is generated when an abnormal condition is detected, it is possible to improve not only the visual but also the auditory sense of the worker. This also improves the reliability of anomaly notification to a certain extent.

However, even in cases such as the above, if the alarm lamp simply lights up in the event of an abnormality, or if the alarm sound generator continuously emits an alarm sound, it becomes difficult to concentrate on sewing work, etc. It cannot be said that the reliability of abnormality notification to the workers who are using the system is sufficient. In addition, by activating the alarm sound generator and alarm lamp with clock pulses of different frequencies, the alarm lamp may blink, or the alarm sound from the alarm sound generator may be made intermittent. However, in such a case, it is necessary to install an expensive oscillator for each alarm lamp and alarm sound generator to generate clock pulses of different frequencies, which increases the cost of the equipment. However, the problem was that it became complicated.

Purpose The present invention has been made against the background of the above-mentioned circumstances, and its purpose is to provide a simple system that can notify the worker of the abnormality not only visually but also through the auditory senses when an abnormality occurs in the sewing machine. Another object of the present invention is to provide an inexpensive abnormality warning device for a sewing machine.

Solution To achieve the above object, the present invention provides: (a) a clock generator that generates a reference clock pulse at a predetermined frequency; and a clock generator that receives the reference clock pulse and performs arithmetic processing operations for controlling sewing machine operation. In an electronically controlled sewing machine that is equipped with a command control circuit that generates various operation command signals and whose sewing machine operation is controlled according to the operation command signals, (c) a detector disposed at a predetermined part of the sewing machine to detect and generate an abnormality detection signal; (d) an alarm sound generator disposed on the sewing machine frame for audibly alerting a worker of the occurrence of the abnormal condition; and (e) a first alarm lamp for determining a blinking frequency of the alarm lamp.
and a reference clock pulse from said clock generator for generating, respectively, a clock pulse having a frequency of 1 and a clock pulse having a second frequency higher than the first frequency for determining the frequency of generation of an alarm sound from said alarm sound generator. (f) a signal response circuit responsive to the abnormality detection signal for supplying clock pulses of the first and second frequencies to the alarm lamp and the alarm sound generator, respectively. It is something that

By doing this, in response to the abnormality detection signal generated when the detector detects an abnormal state of the sewing machine, the reference clock pulse generated from the clock generator for controlling the operation of the sewing machine is generated. The first one determines the flashing frequency of the alarm lamps generated by dividing the frequency in the frequency dividing circuit.
a clock pulse with a frequency of
Clock pulses at a second frequency higher than the frequency of are supplied to the alarm lamp and alarm tone generator, respectively, in the signal response circuit, so that the alarm lamp flashes at a relatively low frequency in accordance with the clock pulse at the first frequency and An alarm generator is caused to generate an alarm intermittently at a relatively high frequency in accordance with the second frequency clock pulse.

Effects of the Invention Therefore, according to the present invention, when an abnormal state occurs in the sewing machine, the blinking of the alarm lamp and the sound of the alarm are suppressed by using the reference clock pulse output from the clock generator to control the operation of the sewing machine. Since there is no need to provide an expensive oscillator for intermittent occurrence, the device becomes cheaper and simpler, and the intermittent alarm sound and blinking alarm lamp make it possible to more reliably identify abnormalities in the sewing machine through the operator's sight and hearing. This has the effect of notifying the status.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

In FIG. 1, reference numeral 1 denotes a bracket arm, and the bracket arm 1 has a head 2 and a pillar part 3 at both ends thereof, and a lower part of the pillar part 3 is a base part 4.
Supported by.

On the front surface of the bracket arm 1, there is a push button 5 which is an operator operation means for selecting a desired stitch pattern from among a plurality of predetermined stitch patterns.
and a display board 7 on which pattern symbols 6 representing the various types of stitch patterns are posted, and the pattern symbols 6
A plurality of light emitting diodes 8 are respectively attached close to the upper part of. The pattern symbols 6 at the lighting positions of these light emitting diodes 8 represent the selected stitch pattern. A sewing needle 9 that is reciprocated up and down by a known mechanism and a presser foot 10 that presses the work cloth by a known mechanism are provided below the head 2. 11 is a start/stop push button;
1 to 14 are speed setting push buttons.

As shown in the block diagram of FIG. 2, the sewing machine configured as described above includes a clock generator 15, a pattern selection device 16, a stitch forming control device
7. A sewing machine motor speed control device 18 and an abnormality alarm device 19 are provided.

The clock generator 15 generates a predetermined constant reference clock pulse signal CP in order to supply a reference signal for controlling the operation of the sewing machine to a command control circuit that performs various arithmetic processing operations and generates operation command signals.
This is an ordinary crystal oscillator that generates (approximately 8 microsecond period).

The pattern selection device 16 is linked to the pattern selection push button 5 in order to select a desired stitch pattern and simultaneously supply a coded pattern signal SM representing the selected stitch pattern to the stitch formation control device 17. One terminal of the switch 21 is connected to the + power supply, and the other terminal is grounded via the resistor 22 and connected to the input terminal of the AND circuit 23. The frequency dividing circuit 24 divides the frequency of the input reference pulse signal CP and supplies a low frequency output signal (approximately 0.5 second period) to the AND circuit 23. Pattern selection counter 2
5, the pattern selection push button 5 is pressed and the switch 2 is activated.
1 is closed, the output signal of the frequency dividing circuit 24 is supplied via the AND circuit 23 and counted, and a code signal representing the counted contents is sequentially sent to the decoder 26 and the stitch forming control device 17. supply to. The decoder 26 sets one output terminal corresponding to the content of the code signal to "L" level, and has a plurality of light emitting diodes 8 whose anodes are commonly connected to the + power supply via a resistor 27. Since the cathode side is connected to the output terminal of the decoder 26, one light emitting diode 8 connected to the output terminal which is at "L" level lights up.
That is, the pattern selection push button 5 is pressed to sequentially move the lighting positions of the light emitting diodes 8, and at the lighting position where the desired stitch pattern is displayed, the push button 5 is released to select the stitch pattern. Therefore, the code signal output from the pattern selection counter 25 in this state is also the pattern signal SM representing the desired stitch pattern.

The stitch formation control device 17 receives the supplied pattern signal.
A stitch data generating device 29 that sequentially generates a series of stitch data for forming the stitch pattern represented by SM in synchronization with the rotation of the sewing machine main shaft and supplies it to a stitch forming drive circuit 28; a stitch forming drive circuit 28 that generates drive power to determine the rotation position of the feed adjuster that adjusts the swing position and the amount and direction of cloth feed according to the stitch data; This is a known device that includes a stitch forming actuator 30 that generates a driving force and positions the sewing needle and feed adjuster.

The sewing machine motor speed control device 18 includes a speed command circuit 32 that generates a speed command signal based on the operation of the speed setting pushbuttons 12 to 14 or the foot controller.
, a speed detection circuit 33 that detects the actual rotational speed of the sewing machine motor 36 and generates a speed signal, and a thyristor firing circuit based on the deviation between the speed command signal and the speed signal so that the deviation becomes zero. An arithmetic circuit 34 calculates timing and generates an ignition signal every drive power cycle, and a motor drive circuit 35 ignites a thyristor based on the ignition signal and supplies power to the sewing machine motor 36 to drive it. This is a known device equipped with the following.

Frequency divider circuit 24 and AND circuit 2 in the above device
3. The pattern selection counter 25, the stitch data generator 29, and the arithmetic circuit 34 form the command control circuit.

The abnormality alarm device 19 detects an abnormal state of the sewing machine and not only displays the abnormality but also notifies the user with an alarm sound. An abnormality detector 38 is provided which detects the occurrence of various abnormal conditions in the sewing machine such as erroneous operation of the start/stop push button 5 and generates an abnormality detection signal SI, and the signal SI is supplied to an input terminal RT of a counter 39. The counter 39 is supplied with a reference clock pulse signal.
A frequency dividing circuit that counts CP and a signal response circuit that controls the output signal of the frequency dividing circuit based on the abnormality detection signal SI are built in. That is, as shown in FIG. 3, the frequency dividing circuit divides approximately 0.25 at a predetermined digit position in the parallel output signal representing the counting content of this circuit.
A clock pulse CP1 of a first frequency with a period of seconds and a second clock pulse CP of a frequency of approximately 15 milliseconds.
2 and a clock pulse with an alarm frequency of approximately 1 ms.
It is capable of generating three types of bit signals with CP3, and the signal response circuit resets the counting contents when the abnormality detection signal SI is not supplied to prevent the above three types of bit signals from being output. It is. The clock pulse CP1 is supplied via a resistor 41 to the base of an NPN transistor 40 whose collector and emitter are connected to the common anode and ground terminal of the light emitting diode 8 in order to periodically flash the alarm lamp. is driven periodically. On the other hand, the clock pulse
CP2 and clock pulse CP3 are each supplied to the input terminal of an AND circuit 42, and the output signal of the AND circuit 42 is supplied to a buzzer 43, which is an alarm sound generator built into the bracket arm 1. Therefore, when the abnormality detection signal SI is supplied to the counter 39, the signal response circuit within the counter 39 releases the reset state of the frequency dividing circuit within the counter 39.
The frequency dividing circuit divides the frequency of the reference clock pulse CP and outputs a bit signal of a predetermined digit. The outputted clock pulse CP1 of the first frequency drives the NPN transistor 40 to periodically ground the anode potential of the light emitting diode 8, and causes the light emitting diode 8 for pattern selection display to blink periodically as an abnormality warning lamp. . When the clock pulse CP2 of the second frequency and the clock pulse CP3 of the alarm sound frequency output at the same time are respectively supplied to the AND circuit 42, a signal having the waveform shown at B2 in FIG. 3 is sent from the circuit 42 to the alarm sound generator. It is output to a certain buzzer 43 and generates a warning sound with a period of about 1 millisecond (frequency of 1 KHz) intermittently at a cycle of about 15 milliseconds.

In this way, since the alarm lamp for abnormality display is also used as the light emitting diode 8 for pattern display, parts and installation volume for the alarm lamp are not required. A clock pulse CP1 for blinking the alarm lamp 8 and a clock pulse CP for intermittent sounding of the buzzer 43 by a single frequency dividing circuit using the output signal of the provided clock generator 15.
Since the two types of signals (2 and 2) are generated by a simple circuit, an expensive oscillator is not required and the device can be made inexpensive.

The operation of this embodiment will be explained below.

When the main power switch (not shown) is turned on and power is supplied to each circuit shown in FIG. 2, the clock generator 15 operates and generates the reference clock pulse.
CP is a frequency dividing circuit 24, a stitch data generator 29,
The signal is supplied to an arithmetic circuit 34 and a counter 39. The pattern selection device 16 operates to select a predetermined stitch pattern based on the operation of the pattern selection pushbutton 5 and the reference clock pulse CP, and the stitch formation control device 17 performs an operation based on the pattern signal SM and the reference clock pulse CP. The sewing machine motor speed control device 18 performs an operation to form a predetermined stitch.
The reference clock pulse CP is based on the output signal from
A predetermined speed control operation is performed using this as an arithmetic processing timing clock pulse, and the sewing operation of the sewing machine is performed. In this state, the reference clock pulse CP is supplied to the counter 39, but the abnormality detection signal SI is not supplied.
The counting contents of the frequency dividing circuit built into the circuit 9 are always reset, and each predetermined bit signal is not generated at all.

Next, lock the sewing machine motor, select the needle hole word,
When various abnormal conditions occur, such as thread breakage or incorrect operation of the start/stop button when using the foot controller, the abnormality detector 38 detects these abnormalities and supplies an abnormality detection signal SI to the counter 39. do. The signal response circuit releases the reset state of the frequency divider circuit, so that the reference clock pulse CP is divided into a first frequency clock pulse CP1.
operates the NPN transistor 40 to cause the lit light emitting diode 8 to blink at the frequency of the pulse CP1 to display the stitch pattern, and at the same time, the clock pulse CP2 of the second frequency is applied to the AND circuit 42.
is intermittently opened, so the clock pulse CP3 at the alarm frequency is supplied to the buzzer 43, and the buzzer sound at the frequency of the clock pulse CP3 is supplied to the clock pulse.
It is generated by an intermittent sound at the frequency of CP2.

As described above, according to this embodiment, when an abnormal state of the sewing machine occurs, two or more types of signals including clock pulses CP1 and CP2 of two types of first and second frequencies are used to control the operation of the sewing machine. These clock pulses CP1 and CP2 cause the light-emitting diode 8 to blink, and the buzzer 43 makes a buzzing sound intermittently. Since clock pulses CP1 and CP2 can be generated, there is no need to install an expensive oscillator etc. to generate clock pulses CP1 and CP2, etc., and an inexpensive and simple abnormality alarm system can reliably notify the abnormal state of the sewing machine to the operator visually and audibly. It will be done.

What has been described in detail above is merely one embodiment of the present invention, and it goes without saying that the present invention should not be construed as being limited thereto.

For example, although the warning lamp in the embodiment described above also serves as the light emitting diode 8 of the pattern selection device 16, an independent warning lamp may be provided.

The signal response circuit built into the counter 39 only needs to control the frequency dividing circuit to output a predetermined bit signal of a predetermined digit in response to the input of the abnormality detection signal SI. A method may be adopted in which a gate circuit that can control the output is provided.

Furthermore, the buzzer 43 may be of a piezoelectric type, an electromagnetic type, or an electrostatic type, since it is sufficient that the buzzer 43 generates an intermittent alarm sound at at least the second frequency by supplying the clock pulse CP2 of the second frequency. do not have. In this case, in a type of buzzer in which the sound frequency is self-oscillated by supplying DC power to the buzzer, the clock pulse CP3 of the alarm frequency does not need to be supplied.

Furthermore, the counter 39 and the AND circuit 42 can be included in a microcomputer element together with the frequency dividing circuit 24, the AND circuit 23, the pattern selection counter 25, the stitch data generator 29, and the arithmetic circuit 34 that constitute the command control circuit. be.

[Brief explanation of the drawing]

FIG. 1 is a front view of a sewing machine equipped with an abnormality warning device according to an embodiment of the present invention. FIG. 2 is a block diagram showing the circuit of the sewing machine of FIG. 1. FIG. 3 is an explanatory diagram of the operation of the embodiment shown in FIG. 8... Alarm lamp (light emitting diode), 15...
...Clock generator, 38...(Abnormality) detector, 3
9... Frequency divider circuit, signal response circuit, (counter), 4
3... Alarm sound generator (buzzer), CP... Reference clock pulse, CP1... Clock pulse of first frequency, CP2... Clock pulse of second frequency, SI... Abnormality detection signal.

Claims (1)

[Scope of Claims] 1. A clock generator that generates a reference clock pulse at a predetermined frequency, and a command control device that receives the reference clock pulse, performs arithmetic processing operations for controlling the operation of the sewing machine, and generates various operation command signals. In an electronically controlled sewing machine, which is equipped with a circuit and whose sewing machine operation is controlled according to the operation command signal, the sewing machine is operated to detect the occurrence of an abnormal condition unsuitable for the stitch forming operation of the sewing machine and generate an abnormality detection signal. a detector disposed at a predetermined location; an alarm lamp disposed on the front side of the sewing machine frame for visually alerting the worker to the occurrence of the abnormal condition; an alarm sound generator disposed on the sewing machine frame for issuing an alarm; a clock pulse of a first frequency for determining the flashing frequency of the alarm lamp; and a clock pulse for determining the frequency of generation of the alarm sound from the alarm sound generator. a frequency divider circuit for dividing a reference clock pulse from said clock generator to generate clock pulses at a second frequency higher than a first frequency of said clock pulses, respectively; and a signal response circuit responsive to the abnormality detection signal for supplying a lamp and an alarm sound generator, respectively. 2. The abnormality alarm device for a sewing machine according to claim 1, wherein the signal response circuit enables the frequency dividing operation of the frequency dividing circuit while the abnormality detection signal is generated. 3. The frequency dividing circuit includes a counting circuit that counts reference clock pulses from the clock generator;
The counting circuit performs a counting operation while the abnormality detection signal is generated to generate a counting signal, and outputs bit signals at two predetermined digit positions in the counting signal as clock pulses of the first and second frequencies. An abnormality alarm device for a sewing machine according to claim 2, characterized in that: