JPS61154693A - Self-judging standard setting type perforation and judge system and apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to an autonomous judgment standard setting type perforation skipping judgment method and its judgment device, and in particular to sewing speed, stitch spacing,
Autonomous judgment standard setting that can automatically set normal judgment criteria whenever parameters such as fabric type/thickness or thread thickness change, and detect and judge abnormal skipped stitches. This invention relates to a perforation skipping determination method and its device.

(o) Background of the Invention Conventionally, there are detection methods that have been proposed to detect skipped stitches, a condition in which the upper thread and lower thread are not entangled and no seam is formed in sewing using a sewing machine. Since the skipped part does not form a stitch, there is a technique that detects the skipped part by comparing the amount of thread used in normal times by taking advantage of the fact that the amount of thread used (the amount of thread fed out) in that part decreases.

For example, patent application No. 59-1219 by the same inventor as the present application.
The specification of No. 05 discloses a skipped stitch detection device based on the above technique. The outline is as follows.

That is, the same inventor confirmed the results using a sensor that detects the amount of thread supplied as shown in FIG. According to the yarn feeding amount (or yarn feeding rate)
The relationship between (within certain limits).

That is, FIG. 1 shows a principle diagram of a yarn supply sensor (for example, a commercially available rotary encoder from C0PAL).
1, a transparent disc 2 having radial light-shielding parts S at equal intervals is attached to a yarn drum 3, and the thread F is inserted between the discs 2.
An electric sensing part 4.4' is provided to detect the amount of feed-out of the lead-out line 5 from the rotation angle of the disc 2 when the wound yarn F wound around the yarn drum 3 is paid out. .5'
Electrical pulses are generated from the sensing section 4 via the sensing section 4.

The reason why the two sensing sections 4,4' are provided is to sense forward rotation and reverse feed-out of the yarn accompanied by instantaneous reverse rotation of the yarn drum 3, as will be described later.

FIG. 2 shows that an electric sensor is provided to detect each cycle of the vertical movement of the needle 7 of the sewing machine 6, and the sensor includes, for example, a marker means 9 attached to the outer periphery of the flywheel 8 of the sewing machine. A second sensing section 10 similar to the sensing section 4 in the figure is attached, and the period of the vertical movement of the hand 7 is sensed from the rotating state of the flywheel 8 via the sensing section 10, and the electrical pulse output is detected at 911. The thread is processed and sent to a processing device (not shown), and the relationship between the amount of thread fed out and the vertical movement of the sewing machine needle is determined. For example, the radial light shielding portion S of the disk 2 (FIG. 1) constituting the yarn supply amount sensor 1 is 12
Divided, sewing pitch of 1 stitch 1.8mm + binding,
It is known that when sewing at a speed of 10 m/min, seven electrical pulses can be detected during one vertical movement (one cycle) of the sewing machine needle.

FIG. 3 shows the power spectrum of yarn speed, with the dimensionless frequency f/N (N being the vertical vibration frequency of the needle) plotted on the horizontal axis.

As can be seen from the figure, the movement of the thread is mainly composed of the integer component of the vertical movement of the sewing machine needle.

This means that if you synchronize with the vertical movement of the needle and perform sampling at the appropriate timing, you can remove the high-order components that are superimposed on the thread speed and count the amount of thread consumed per stitch of pure knitting. It means.

It should be noted that during sewing, it is known that there is also a repulsion of the sewing thread itself, and that the thread may temporarily move in the opposite direction. If a counter or arithmetic device is provided that counts down as the thread moves up and in the opposite direction, skipped stitches can be detected. If there are more than a predetermined number of backward pulses, for example, 6 out of 7 generated pulses
What if 1 is a forward direction pulse and 1 is a reverse direction pulse? -1
It is possible to determine that skipped stitches have occurred when a reverse direction pulse is generated exceeding =6.

(1) Problems with the Prior Art According to the perforation skip detection method according to the prior art described above, it is possible to detect skipped stitches quite accurately. With the combined method disclosed as an example, it was possible to detect skipped stitches more accurately.

However, in the skipped stitch detection method according to the prior art, considering the fact that parameters such as sewing speed, stitch spacing, and fabric thickness are often subject to process changes, the effort required each time to set standards is significant. This had become a problem.

(B) Purpose of the Invention Therefore, the present invention solves the above problem in view of the above problems, and even if parameters such as sewing speed, stitch spacing, or fabric thickness and type are changed, To provide a perforation skipping determination method and its determination device that can autonomously set normal determination criteria in response to the situation, and can flexibly handle operations according to the requests of wire fabricators. is intended to provide.

(E) Embodiment of the Invention FIG. 4 shows the configuration of a determination device that implements the autonomous determination criterion setting type perforation skip determination method according to the present invention. In the same figure, 100 is a statistical command circuit, and 101 is a statistical processing circuit that calculates the average thread feed amount (supply amount) according to whether sewing is successful or unsuccessful (whether there is skipped stitches). 102 is a pulse measuring circuit, and the forward direction sending pulse and the backward sending pulse of the yarn emitted from the sensing parts 4 and 4' of the yarn supply sensor 1 as shown in FIG. 1 are shown in FIG. This circuit adds and subtracts every predetermined synchronization pulse from the synchronization sensor and measures the sewing state as to whether or not there is a skipped stitch. Reference numeral 103 denotes a measurement value determination circuit, which compares the data representing the limit feed-out amount of thread calculated by the statistical processing circuit 102 with the data representing the actually measured sewing state from the pulse measurement circuit 102, and determines the stitch skipping. This is to determine the condition. Reference numeral 104 denotes an output circuit, which receives the output from the previous measurement value determination circuit 103 and generates an error signal indicating that a skipped stitch condition has occurred.

The operation of the determination device according to the present invention configured as described above will be described next.

As described above, the pulse measurement circuit 102 receives the pulses from the yarn supply sensor 1 shown in FIG. 1 in synchronization with the synchronous pulses from the synchronous sensor accompanying the vertical movement of the needle shown in FIG. Therefore, it is possible to measure the state in which the thread is being paid out using a certain distance that the thread is being paid out as one unit. For example, in an example where 7 pulses are generated in one cycle during normal sewing, the pulses are added up, and if there is one reversal of the thread, 7-1 = 6, and if there are two reversals, then is 7-2
=5.

Under such measurement conditions, the statistical command circuit 100 is turned on and a statistical command is sent to the statistical processing circuit 101.
00, the statistical processing circuit 101 starts statistical processing based on the measured pulses from the pulse measuring circuit 102. That is, the same for every fixed period of synchronization pulse,
Statistics are collected for a predetermined number of times of measurement data indicating the amount of thread supplied under sewing conditions, for example, 50 times or 100 times, and the average amount of thread supplied is calculated digitally. Calculate the value.

By doing so, you can know the average amount of thread supplied under the same sewing conditions, and therefore the state of occurrence of skipped stitches, and depending on where you take the deviation from the average value, the normal standard value under the same conditions can be determined. Can be configured autonomously and automatically.

The reference value calculated in this way is sent to the measurement value determination circuit 10.
3, and the actual measured data from the pulse measuring circuit 102 between predetermined synchronizing pulses is also given to the determination circuit 103, and the actual measured data is compared with the reference value that can be considered normal under the same sewing conditions to determine whether there is a skipped stitch. Detect. In other words, if a standard value is set as a range that allows a predetermined number of occurrences of skipped stitches, actual measurement data that deviates from the standard value indicates the occurrence of an unacceptable skipped state. It is possible to display the occurrence of a skipped stitch condition on a display device (not shown) using the output of the sewing machine (which can be configured), or to automatically stop the sewing machine when a skipped stitch condition occurs.

In addition, in the present invention, when parameters such as sewing speed, sewing interval (pitch), type of cloth, thickness, etc. that constitute sewing conditions are changed, the amount of thread fed out (supply amount) is calculated using a statistical processing circuit. Since the average value for a predetermined number of times is calculated each time by learning, a normal reference value can be autonomously set each time the sewing conditions change.

(F) Effects of the Invention As described above, in the judgment method and judgment device according to the present invention, by being equipped with a statistical processing function, normal reference values under the same sewing conditions can be determined autonomously, and When changing to another different sewing condition, another normal reference value is determined, so that changes in parameters can be dealt with conveniently and flexibly.

Furthermore, in the determination device according to the present invention, the above-mentioned patent application
It goes without saying that the composite method disclosed in the specification of No. 9-121905 can be used in combination.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a yarn supply amount sensor used in the present invention;
FIG. 2 is a schematic configuration diagram of a synchronous sensor used in the present invention,
FIG. 3 shows the power spectrum associated with the pulses obtained by the sensors of FIGS. 1 and 2, and FIG. 4 shows the configuration of an autonomous judgment criterion setting type perforation skipping judgment device according to the present invention. In the figure, 100 is a statistical instruction circuit, 101 is a statistical processing circuit,
102 is a measurement circuit, 103 is a measurement value determination circuit, and 104 is an output circuit. Patent applicant G-Dinis Co., Ltd.
Marvelt Associates Co., Ltd. Figure 3 f/N□

Claims (2)

[Claims] (1) Means for generating a synchronization signal corresponding to each cycle of the vertical movement of the sewing machine needle, detecting the amount of thread being fed out, and generating a digital signal corresponding to the amount, and means for counting the generated digital signal. and statistical processing means for repeating and statistically processing the digital signal occurring between predetermined synchronization signals a predetermined number of times to calculate statistics such as variance of the digital signal corresponding to the amount of yarn being fed out. , autonomously sets each normal stitch skip judgment standard value from different statistics calculated according to the sewing conditions, and compares the measured value of the digital signal from the measuring means with the judgment standard value to determine the stitch skip. An autonomous judgment standard setting type perforation skipping judgment method characterized by judging the occurrence of a condition. (2) A first signal generating means that generates a synchronizing signal corresponding to each cycle of the vertical movement of the sewing machine needle, and a second signal generating means that senses the amount of sewing thread fed out and generates a digital signal corresponding to the amount. a generating means, a measuring means for measuring the digital signal, and a measuring means connected to the measuring means to repeatedly count the number of the digital signals generated between predetermined synchronization signals a predetermined number of times, and correspond to the average yarn payout amount. a statistical processing means that autonomously calculates a reference value to be measured; and a statistical processing means that compares the reference value from the processing means and the actual measurement data from the measurement means, and skipped stitches occur when the actual measurement data exceeds a predetermined tolerance value. An autonomous judgment standard setting type perforation skipping judgment device.