JPS6324715B2 - - Google Patents

Description

[Detailed description of the invention] In sewing machine sewing, two pieces of paper are sewn together,
The seam allowances of synthetic resin, rubber, film, cloth, etc. (hereinafter referred to as fabric) may not overlap properly, or there may be insufficient seam allowance due to poor cutting, etc., and two pieces of fabric may not overlap properly. The seam cannot be sewn together and the seam position is incorrect, or the thread has become frayed from the seam and the perforation is not working and the seam is opening, or the perforation is completely outside the specified perforation line of the seam. The best way to prevent defects in sewing, which are so-called "punctures at seams" (hereinafter referred to as punctures), where the openings are left open without being sewn together, is to improve the skills of the seamstress and call attention to them, or to increase the quality of the product during inspection. In either case, it is necessary to rely on human labor, either by reinforcing the seams and pulling the seams of each piece by hand to inspect and discover if the puncture remains or is likely to become a puncture (described below as an approximate puncture). The current situation is that we cannot afford it. How to detect a puncture manually
The disadvantages include that it is difficult to detect 100% complete punctures, that it is inefficient and costly, and that preventive measures are not taken at all. A simple method for detecting punctures using a mechanical device has been developed in which a micro switch is used, and when a puncture occurs, the bar of the micro switch enters the puncture area and the micro switch is activated. There are many different types of patterns, and no device has been developed that can easily and accurately detect punctures in response to all types of sewing patterns.

The present invention eliminates the above-mentioned drawbacks due to manual work, can easily adapt to any sewing pattern, and contributes to the complete automation of sewing in the future. The present invention divides a large number of target sewing items into sample sewing and mass production sewing, and performs sample sewing in which one or several items are sewn normally, and then sewing in the same pattern as the sample sewing. This is a method that uses a sensor to measure and store data necessary for normal sewing by sewing samples of normal sewing methods to detect punctures during mass production sewing. The change in the seam allowance is measured together with the periodic signal of the needle movement of the sewing machine and stored in the storage device, and then the change in the seam allowance that matches the periodic signal measured during mass production sewing is measured and the data is stored. It is calculated, compared with the stored data, and determined based on predetermined condition values.If the condition values are not met, for example, the average thickness is 1.5 mm and the thickness is 5 ^cm2 ,
If the data obtained from mass production sewing is 7.3 compared to the number 7.5 multiplied by both, or conversely, if the maximum allowable value of the difference between the two data is set under a predetermined condition and this is exceeded, an abnormality will occur. The purpose of this invention is to emit the necessary output to report the occurrence of a puncture, assuming that a puncture has occurred, and to prevent future occurrences. The structure of the present invention that achieves the above object will be explained as follows.

Normally, when sewing clothing, tens or hundreds of pieces are made into a one-size lot, and when sewing industrial items such as shoes or paper bags, a single lot consists of thousands or tens of thousands of pieces. It's summery.

In other words, it is customary to sew one piece of clothing and then sew the rest using the same exact pattern, and even for women's clothing, whose patterns change most frequently, dozens of pieces are made into a single lot. Therefore, one or several pieces are sewn as samples, data on the seamed portion is taken, and based on the normal data, it is accurately determined whether the subsequent mass-produced sewing is punctured or not. The cause of punctures is that the stitching position is incorrect, or that the cut cloth, paper, synthetic resin, film, etc. is not cut to the correct size or shape. A gap in the seam is a sign that a puncture or near-puncture has occurred. There is not enough seam allowance. The stitching position is not accurate. The thickness of the seamed part has changed compared to normal. The present invention detects all of these symptoms using a seam allowance measurement sensor. The seam allowance measurement sensor is a combination of infrared rays and a photodiode, infrared rays and a video camera, or a fixed image sensor, which analyzes changes in the overlap of single, double, or triple fabric as shadows through light from the surface. A sensor that can accurately analyze the overlap of fabrics that can be seen through, a method that uses ultrasonic waves or a digital gauge to determine the overlap of fabrics based on changes in thickness, or a combination of the above two, or This can be done by combining various sensors. As a result, there are four symptoms that indicate that a puncture has occurred: (a) changes in thickness and (b)
It can be summarized into two points (a) and (b), which are changes in the overlapping situation of the fabric in the sewn part, that is, changes in the seam allowance, and these two points (a) and (b) are measured using a seam allowance measurement sensor. By accurately measuring and analyzing, it is possible to accurately determine the occurrence of a puncture. As a means of detecting abnormalities by comparing them with normal seam allowances or thickness, in the case of simple stitching, it is possible to accurately check by simply comparing the seam allowance or thickness at any fixed position of the sewn product, but with complex sewing patterns, slight If the risk of punctures is also required to be precisely checked, it is necessary to grasp changes in thickness and seam allowance by area, limit it to a particular area, and enlarge it to grasp the situation to improve accuracy, or Conditional values can be set in a fixed range so as not to pass even quantitative changes, and by incorporating these into the program in advance, it can be easily operated and accuracy can be improved. Along with the seam allowance measurement sensor, the periodic sensor is attached to a device that drives or transmits the vertical movement of the sewing machine needle, such as a shaft or flywheel of the sewing machine that moves in synchronization with the sewing machine needle. The sewing machine sensor uses the vertical movement of the sewing machine needle as a periodic signal, and is used as a lot number or division number when performing addition/subtraction calculations on the data obtained from the seam allowance measurement sensor during one cycle or any fixed cycle. . In other words, it is used as a lot number to find a fixed position in a fixed section where the area of the seam allowance obtained by the seam allowance measurement sensor is totaled, or in the case of fixed position measurement.

FIG. 5 shows the system configuration of the present invention. As a first step, by sewing a sample of the target sewing product, data on the correct seam allowance area, position, thickness, or a combination of the three mentioned above is measured by a seam allowance measurement sensor, and at the same time, periodic signal data is also measured by a periodic sensor. Both data processed by the calculation unit are stored in the storage unit. Next, we move on to mass production sewing, and each sewn product is sewn on a sewing machine or during a separate inspection process, using a seam allowance measurement sensor and a cycle sensor to adjust the seam allowance according to the synchronization signal. Data is measured. The obtained data is computed by the arithmetic function unit and compared with already stored data for judgment. Sample sewing and actual mass-produced sewing are not necessarily exactly the same.
Since there are some errors and it is necessary to keep them within generally accepted sewing standards, we have revised the judgment standard values to conditional values that take these into account.
Judgment is made based on conditional values. When a result equal to or greater than the condition value is obtained, output is output to notify that a puncture has occurred. This output is connected to a puncture indicator lamp, an alarm, an automatic sewing machine stop device, a puncture location display labeling machine, etc. to prevent punctures from occurring continuously or to clearly indicate the location of the puncture and to prevent the puncture from occurring continuously. It is effective in preventing shipment.

An embodiment of the present invention having the above-mentioned configuration will be described below.

Figure 1A shows the simplest example of the object to be sewn, in which two strips of cloth 1 are folded in half at the side edges to be sewn together, and the lower cloth is sewn with a certain seam allowance. A perspective view of upper and lower cloths being sewn together using sewing machine stitch 2 is shown. B in Figure 1 shows a plan view when the sewing in A is normal, and C in the figure shows the
A plan view with a puncture at the bottom is shown. In other words, when comparing Ro and Ha, Ro always has a constant seam allowance,
The seams are all triple-thick,
C: At the punctured part 7, the upper fabric does not fold in two, but spreads outward and becomes a single piece of cloth, and the punctured part has a double thickness of cloth, and the seam allowance is also limited to the seam allowance of the upper fabric. It is in a state where there is no. As mentioned above,
In the case of extremely simple punctures, the seam allowance measurement sensor can be used to measure the thickness using a digital gauge. FIG. 3 is a perspective view showing the sewing material shown in FIG. 1 being measured by a seam allowance measurement sensor. The seam allowance measurement sensor can be installed as an accessory part of the sewing machine at a position immediately after sewing is completed by the sewing machine needle, that is, near the sewing machine needle, or it can be installed as a measuring device in the inspection process separately, independent of the sewing machine. In FIG. 3, an infrared light emitter 5 emits infrared light from above the sewing material, and a horizontally elongated photodiode or phototransistor below receives the shadow of the infrared light transmitted through the fabric. The triple-layered part of the sewn item is the darkest and the single-layered part is the brightest due to the transmitted light, which is projected onto the photodiode, and the overlapping situation inside the fabric that cannot be seen from the surface where the fabric is sewn can be seen by the light and shade of the shading. can be grasped. Further accuracy can be achieved by using soft X-rays as a light source instead of infrared rays, or by using a video camera or fixed image sensor that captures the received light as an image instead of a photodiode. FIG. 4 shows a perspective view in which a digital gauge 6 is used as a seam allowance measurement sensor. This is a method that detects changes in the thickness of the fabric at the seam. An iron rod is placed inside an electromagnetic coil, and the iron rod is used as a measurement rod. The iron rod moves when there is a slight change in thickness, and this is exchanged for changes in magnetic force to measure it. It's a method. Multiple digital gauges are used, and the first one is set at the single part of the seam seam, the second one is set at the double part, and the third one is set within 1 to 2 mm of the seam allowance of the lower fabric, allowing changes in seam allowance and thickness. The change can be related to the occurrence of a flat tire. Furthermore, when simply measuring with a digital gauge, even though the sewing is being done normally, the movement of the sewing material shifts and the measurement position shifts, often sending out a false signal indicating the occurrence of a puncture. Attach a sensor to both ends of the fabric to check the position of the sewing item, or install a separate seam allowance measurement sensor, and analyze information from two locations based on the periodic signal from the periodic sensor to prevent malfunctions. Can be done. Therefore, the number of seam allowance measurement sensors and the combination of models can be arbitrarily determined. FIG. 2 shows an example of a sewing item that requires an accurate storage system. FIG. 2A shows a lower cloth having a convex portion on the right side, B shows a facing cloth to be sewn to match the convex portion of A, and FIG. 2C shows an example in which stitching is performed. In the case of Figure 2, there are alternating single and double sections of the fabric in the measurement direction, that is, the vertical direction in the figure, and the seam allowance of the upper fabric is only in the center, so the normal measurement method is not suitable. Only the stitching in the center part is normal.
Any other part will signal a blowout. According to the present invention, when sewing a sample, it is possible to ascertain through the cycle sensor how many cycles, that is, how many stitches or centimeters from the start of sewing, the condition of the fabric changes, and then the seam allowance measurement sensor recognizes the double portion. Next, the position of the facing fabric is confirmed by a periodic sensor, and the seam allowance of the upper fabric only needs to be at the position of the facing fabric, but the seam allowance of the lower fabric is Both sensors measure what is necessary over the length, confirm that the finished sewing is normal, and store the data. At the same time, corrections are made by setting the deviation in the position of the facing fabric and the allowable range of the seam allowance, setting the condition values, and starting the next mass production sewing. During mass production sewing, measured values are compared with stored data and conditional values, and if, for example, a single layer of thickness is measured at the position where the facing fabric should be, a puncture signal is issued. Also, in an extreme example, it is not necessary that all of the facing fabric is sewn to the lower fabric, and if 70% of the facing fabric is sewn to the lower fabric, it is determined not to be a puncture.
By passing through one circuit for determining whether top stitching has been performed or not, it is possible to determine that 70% or more of the lines are pass lines.

The present invention is not limited to sewing using a sewing machine, but can also be used to improve the quality of the joints of paper, film, rubber, synthetic resin, wetsuits, tent fabrics, etc. by joining using ultrasonic waves or high frequencies, using adhesives, etc. It is also possible to detect defects. In this case, the periodic signal is detected by attaching a sensor to the drive device that sends out the object to be detected. As mentioned above, it can accurately measure multiple sewing situations, so it can be used to detect any item during work.
There is no other reason why it cannot be used. Therefore, since inspection is performed correctly for everything from simple items to complex items, it is possible to reliably save labor for inspection. In addition, manual inspection is done by looking at the surface or pulling it out, so obvious punctures can be detected, but approximate punctures such as insufficient seam allowance or abnormal folding inside the seams can be detected. Although it is difficult to detect punctures reliably, the present invention can detect almost 100% punctures and approximate punctures by setting conditional values and combining the seam allowance measurement sensor. Conventionally, increasing the detection accuracy tends to cause malfunctions, and due to the high number of malfunctions, the inspection equipment is unreliable and relies on manual labor.However, according to the present invention, the sewing situation can be checked using a periodic sensor. It is measured every stitch (if necessary, multiple periodic sensors are used to measure with a time lag, it is possible to measure every 1/2 to a few fractions of a stitch), and then it is divided into parts, and the parts are compared and the whole is measured. In order to make a comparison, even if the measurement sensor detects an abnormal signal due to vibration, a loose thread between one or two stitches, wrinkles, or other causes, the result will immediately signal that a puncture has occurred. It never emanates. Accidental abnormal signals that do not cause a puncture are eliminated by the program and system of the determination device, which consists of a sample seam allowance storage unit, an arithmetic function unit, and a determination unit, and only signals that truly cause a puncture are compared and determined. This method prevents malfunctions. Paper, film, fabric, etc. are stiff and soft, making it difficult for mechanical detection methods to detect them, and there have been problems with wrinkles and scratches on the item. The present invention minimizes the method of measuring by directly applying slight pressure to the object to be detected, and performs measurement processing using shadows or images projected by light, so it does not have the above-mentioned drawbacks and can be detected with extremely simple handling. . Therefore, the present invention has the following effects. In other words, this method does not detect punctures manually, but has an extremely accurate puncture detection effect that cannot be achieved manually.

Since the memory method is based on sample sewing, basic data for judgment criteria can be inputted very easily without inputting special data, thereby increasing the detection effect.

By using periodic signals, accurate measurements can be made regardless of the sewing speed, and false alarms are extremely low.

Since it uses a periodic signal, it can be measured regardless of the sewing machine speed, and can be used for normal foot-operated sewing, or for general sewing methods such as sewing slowly at beginnings and complicated parts, and sewing quickly at easy parts. Highly versatile.

In addition to detecting punctures, it is also possible to detect defects in seam lines, defects in folded parts, etc., depending on the method of setting condition values, measurement positions, and judgment methods.

It is possible to automatically detect punctures, which is extremely important in automating sewing, and can greatly contribute to automation of sewing.

[Brief explanation of the drawing]

Fig. 1, A...Stitching perspective view, B... Normal stitching plan view, C... Defective stitching plan view, Fig. 2, A... Convex fabric plan view, B... Facing fabric plan view, H... Fabrics of A and B. Sewing plan view, Fig. 3, Perspective view of optical sensor type seam allowance detector, Fig. 4, Perspective view of digital gauge type seam allowance detector,
1...Fabric, 2...Sewing machine seam, 3...Seam allowance, 4...Photodiode (horizontal type), 5...Infrared emitter,
6...Digital gauge, 7...Puncture part, FIG. 5, System configuration diagram of the present invention.

Claims (1)

[Claims] 1 Measure changes in the area and position of the seam allowance, changes in the thickness of the seamed parts, etc. in the seamed parts of sewn products such as paper, synthetic resin, rubber, film, cloth, etc. (hereinafter referred to as fabric) A seam allowance measurement sensor (hereinafter referred to as seam allowance measurement),
A sensor device consisting of a periodic sensor that detects a signal of any state of the drive movement of the sewing machine needle as a periodic signal, a seam allowance memory unit that stores the measured data, and a sensor device that stores the measured data at any period. A determination device consisting of three units in total: a calculation unit that performs arithmetic processing on the data, a determination unit that compares and determines the data stored in the storage unit and the data that is currently being measured by the sensor device; A small sample of the sewn part of the fabric that is the object to be measured by the device, or a sample sewing for test purposes, and a large quantity of the same fabric with the same sewn part as the sample sewing. The results of the seam allowance measurement of the seamed parts of the normal fabric of the successfully sewn sample are stored in the memory unit via the sensor, and then used for the actual mass-produced sewing. A determination unit compares and determines the data obtained through the seam allowance measurement sensor device and the sample sewing data stored in the storage unit, and detects data where the numerical value of the determination result does not meet a predetermined condition numerical value. If the
A fabric inspection device that, by displaying and connecting to an automatic device, reports that the sewn portion of the fabric is punctured or has a defective seam that is close to a puncture.