JPS6224544B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring the density of woven and knitted fabrics.

Conventionally, density, which is one of the morphological characteristics of woven or knitted fabrics,
In other words, for measuring the number of threads or stitches in the warp and weft directions per unit length of fabric,
Various methods can be used, for example, to unravel the woven or knitted fabric to separate the threads.
A method in which books are taken out one by one and measured based on the number of books; a method in which the unit field of view is magnified using a lens system and the density is measured from the magnified image; There is a method of using a transparent plate with different cutouts, overlapping the densidometer on the fabric surface with different orientations in the vertical and horizontal directions, and measuring the density from the moiré fringes observed in each case.

Among these methods, the method of loosening the woven or knitted fabric and measuring the number of threads is a reliable method, but
It takes time to produce results and is a completely destructive test that involves cutting out a portion of the fabric for measurement. Further, although the method of enlarging and measuring with a lens system is a non-destructive testing method, it is essentially the same as the method of loosening and measuring the fabric, and the work itself is detailed and complicated. On the other hand, the method using a densidometer is a nondestructive testing method similar to the method using the lens system described above, and moreover, the measurement can be performed in a much shorter time than the above two methods.

However, all of these methods involve human intervention, which inevitably causes various measurement errors, and it is impossible to measure automatically, and furthermore, the measurement results cannot be transferred to other devices in real time. Nor can it be used as a source of information for input into the .

In view of the above, the present invention is a method for automatically and highly accurately measuring the density of woven or knitted fabrics without human intervention, and in particular, the present invention provides a method for automatically and highly accurately measuring the density of woven or knitted fabrics, and in particular, by measuring images of woven or knitted fabrics and sequential intervals. The present invention aims to provide a method in which density measurement is performed through information processing equivalent to superimposition of an image of finely pitched parallel stripes arranged at different angles.

In order to achieve such an object, the density measuring method of the present invention captures an image of a woven or knitted fabric to be measured using an imaging device, and stores it in a memory as two-dimensional shading image information of the fabric having information regarding the density of the woven or knitted fabric. This corresponds to the superimposition of the fabric image and the striped image in an information processing device in which images of parallel shading stripes with fine pitches arranged at varying intervals are stored in advance as striped image information in the memory. This method is characterized by performing information processing and determining the density of a woven or knitted fabric from information on an image corresponding to moiré stripes obtained in memory through the processing.

The method of the present invention will be explained in more detail below with reference to the drawings.

FIG. 1 shows the configuration of an apparatus used to carry out the present invention, in which 1 is a woven fabric to be measured, 2 is an imaging device equipped with an optical system 3 having a zooming mechanism and an imaging tube 4, and 5 is an imaging device equipped with an optical system 3 having a zooming mechanism and an imaging tube 4. 6 is an information processing device consisting of an electronic computer, 7 is a display device, and 8 is a checkered image information memory.

When measuring the density of a woven or knitted fabric, in the above device, a fabric image (FIG. 2A) based on surface reflected light or transmitted light from the woven or knitted fabric 1 placed at a predetermined position is captured by the zooming of the optical system 3. The field of view and magnification are determined by the mechanism, and the field of view and magnification are
An image is captured by an image pickup tube 4 such as a CCD camera,
There, it is converted into fabric image information as an electrical signal. This fabric image information is based on information regarding the density of the woven fabric obtained from the reflection or transmission characteristics of the surface of the woven fabric, and is sent to the information processing device 6 via the interface 5 and stored in the internal memory. stored in the section.

In the information processing device 6, moire fringe image information for density measurement (see FIG. 2 C and E) is electronically generated in the same manner as when a moire image is obtained by a densidometer, and the moire fringes are Information processing is performed to obtain the density of the woven or knitted fabric from the pattern.

To explain this more specifically, the above-mentioned checkered image information memory 8 contains striped image information configured in advance in imitation of the checkered stripes in a general-purpose densidometer, that is, as shown in FIG. 2B and D, the intervals are sequentially changed. An image of finely pitched parallel stripes arranged in a row is stored in the information processing device 6, and information processing corresponding to the superimposition of the fabric image and the stripe image is performed, and the obtained results are obtained through this processing. The density is determined from the information of the image corresponding to moiré fringes.

That is, when the brightness of the surface of the woven or knitted fabric and the brightness of the striped image are superimposed, a new state of thick stripes is created depending on whether the period in the striped direction is synchronized or not. The period of the striped image corresponding to the widest location in the coarse or dense state is displayed as the density of the fabric.

The above processing is performed on the woven or knitted fabric in both the warp and width directions, thereby obtaining information on images corresponding to moiré fringes in each direction (see FIGS. 2C and E). Based on the image information, the information processing device 6 calculates the densities of the woven fabric 1 in both the warp and the lateral directions, and these densities are displayed on the display device 7. Naturally, when measuring the density, correction is made in accordance with the magnification of the zooming mechanism of the optical system 3.

FIG. 2 visually represents the information processing process performed in the information processing device 6. As shown in FIG. That is, A, B, C and A, D in the same figure.
E shows the processing process for measuring the density in the warp direction and the width direction of the woven fabric 1, and by superimposing the woven fabric image A and the striped image B in the warp direction, the density in the warp direction is measured. A moire stripe image C showing the density is obtained, and by superimposing the woven fabric image A and the stripe image D in the horizontal direction, a moire stripe image E showing the density in the horizontal direction is obtained.

In the above description, a case has been described in which an electronic computer is used as the information processing device. However, instead of this, a two-dimensional image information memory that stores fabric image information, and the fabric image information and plaid image information stored in the memory 8 are used. An arithmetic device that creates a logical sum of corresponding pixels with vertical or horizontal striped image information can be used, and image information corresponding to moiré stripes can also be obtained using them.

As is clear from the detailed description above, according to the present invention, density measurements of woven or knitted fabrics can be performed automatically, non-contact, at high speed, and with high accuracy without damaging the fabric.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a device used to carry out the present invention, and FIG. 2 is an explanatory diagram showing the information processing process of images of woven and knitted fabrics. 1... Woven/knitted fabric, 2... Imaging device, 6... Information processing device.

Claims (1)

[Claims] 1. Capture an image of the woven or knitted fabric to be measured with an imaging device, and store it in memory as two-dimensional grayscale image information of the fabric with information regarding the density of the woven or knitted fabric,
In an information processing device in which images of parallel light and shade stripes with fine pitches arranged at sequentially varying intervals are stored in a memory as stripe image information, information processing corresponding to the superposition of the fabric image and the stripe image is performed. A method for measuring the density of a woven or knitted fabric, characterized in that the density of the woven or knitted fabric is determined from information on an image equivalent to moiré stripes obtained in memory by the processing.