JPS5962994A - Counter - Google Patents

Abstract

PURPOSE:To count object materials accurately even if they are moved irregularly by binorizing the scanning signal of the object material and counting the binary signal in every scanning to attain a signal and to count an AND signal between this signal and a binary signal attained a prescribed time before said signal and adding a differential value between both counted values. CONSTITUTION:Optical sensors 2 and 3 are provided in the direction crossing the movement direction of many object materials 5 flowing continuously to detect the object material 5. The outputs of these sensors are binarized in a binary circuit part 7, and the binary signals are counted in a counter 8 for every one scanning of sensor. The AND between these binary signals and the binary signal attained in the binary circuit part 7 a prescribed time before is ANDed 9 and the resultant value is counted in counter 10 for every one scanning. Thereafter, the difference between both counted values is calculated to add the arithmetic result.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a counting device for counting a large number of objects moving on a belt conveyor, for example.

A conventional counting device of this type is shown in FIGS. 1 and 2.

That is, opposing charging switches CL are installed on both sides of the conveyor A perpendicular to the conveying direction B of the belt conveyor A, and the light from the light emitting unit) D is blocked by the moving object E and the light receiving unit) The output signal of the light-receiving unit F (FIG. 2(a)) when the signal F does not reach F is binarized by the binarization circuit G (FIG. 2(b)), and is counted by a number counter.

However, this counting device has a drawback that if the objects overlap when viewed from the photoelectric switch C, a counting error occurs.

Therefore, an object of the present invention is to provide a counting device that can accurately count the number of objects flowing on a belt conveyor or the like even if they are irregularly arranged.

This invention places a line image sensor above an object so as to scan in a direction transverse to the moving direction of the object, binarizes the signal, counts each scan, and outputs the binarized signal. and the binary signal from the sensor at a predetermined time earlier than that, the total number of AND signals is counted, and the difference between the two counts is added to obtain the number.

The operating principle of this invention is shown in FIG. Consider a situation in which a moving object is scanned a number of times perpendicular to the moving direction at predetermined intervals, as shown in FIG. 2(a). Figure (b) shows 2
The digitized signal is displayed visually. The number Nb of this solid line is 3
It is 7. With respect to this signal, FIG. 5C shows a state in which the binary signal is shifted by one scan in the entire movement direction. The same figure (d
) graphically displays the ANDed signals of (b) and (c) in the figure. The number of solid lines NeL is 33. The number N of objects that have moved is determined from the difference in the number of strokes, N=
Nb-Nd=4.

This result is based on the fact that for each object, a scanning line in which the "1" portion does not appear occurs only once by logical performance. As a result, accurate measurements can be made even if the objects move irregularly.

A first embodiment of the invention is shown in FIGS. 4 to 6.

That is, this counting device is provided with a pair of line image sensor heads 2.3'ft facing each other above a belt conveyor l, and a reflecting prism 4 is disposed between them, so that the line field of view P, P, They are located in the width direction of the belt conveyor 10 and arranged at regular intervals l in the moving direction of the belt conveyor 1. This interval l is set by vertically moving and adjusting the reflective prism 4 having an apex angle of 90 degrees, and is sufficiently small compared to the object 5. These sensor heads 2.degree. 3 are depicted by, for example, a large number of light receiving elements such as phototransistors arranged in the shape of a gold wire, and both are synchronously scanned by a reference clock circuit 6. Output signals S (FIG. 5(a)) and C2 (FIG. 5(b)) resulting from each scan of the sensor heads 2 and 3 are sampled and held in the binarization circuit section 7 and then subjected to sensitivity correction. The binarized signal syo' (Fig. 5 (C2) + s2' (Fig. 5 (C2)
d)) Signal 82 for scanning the moving direction side of the object 5
' is counted (count number N2) every time the first counter 8 is scanned. In addition, the signal comparison circuit 9
The logical product signal S3 (FIG. 5(e)) of each heel is counted (count aN□) by the second counter 1° for each scan.

The calculation circuit 11 performs the calculation N2-N for each scan, and the addition circuit 12 adds the results. This addition n-circuit 12 performs intermediate addition of the calculation results of N2-N operations in an intermediate addition circuit 13, and when the resulting value Np becomes a positive number by the positive number determination circuit 14, the value Np'ff: number addition 15, and on the other hand, the intermediate adder circuit is reset.

In this way, the number of objects 5 that have passed through the field of view of the line image sensor heads 2 and 3 is obtained by the number adder 15 as a number output.

Now, in FIG. 6, seven objects 5 in the same figure move and pass in the direction of the arrow with respect to the field of view position (a, C2) of the line image sensor, and as a result, the objects 5 in the same figure
Assuming that scans #a to #a□5 are performed, the counts of counters 8, 10 and circuit 11 for each scan are as shown in the table below.

(The following is a margin) It can be seen that when the sum is taken by the adding circuit 12 of ``1N2-N of the curve formation'', it becomes ``7'', which is the number of objects 5.

A second embodiment of the invention is shown in FIG. That is, this dividing device is arranged so that the entire line field of view of one line image sensor 2' is in the width direction of the belt conveyor, scans it in synchronization with the clock signal of the reference clock circuit 6, and calculates the binary value. A binarized signal s/ is obtained in the converting circuit section 7'. Clock detection circuit 1 reads out this binary signal s2/
6 and a delay circuit 18, such as a shift register 7, delay the entire belt conveyor by a predetermined time, for example, the interval l (Fig. 4), and then convert the delayed signal S' to a binarization circuit that advances by the delay time. The binary signals S and ' of the section 7' are ANDed by the signal comparison circuit 9, and the subsequent processing circuit is the same as that of the first embodiment. The delay circuit 1
8 is delayed in order to AND the binary signal obtained by one scanning of the line image sensor 2' and the binary signal obtained by the subsequent scanning in the total signal comparison circuit 9. It is something. This delay circuit 18 drives the shift register 17 using the read clock detection circuit 16, the clock of the reference clock circuit 6, and the scanning timing of the line image sensor 2'. The shift register 17 has a capacity (
By setting the number of bits) to be the same as the number of light receiving elements of the line image sensor, the output signal (binarized signal) of the line image sensor 2' is recorded and at the same time the binary signal recorded during the previous travel is delayed. It is output as a signal Si' and is exactly -
Signal delay for scanning is performed.

Incidentally, in order to adjust the scanning interval corresponding to the adjustment of the interval 1, the clock frequency of the reference clock circuit 6 may be adjusted.

With this configuration, it has the same effect as the first embodiment. Furthermore, the following points are superior compared to the Ml example. That is, in the first embodiment, two line image sensors 2 and 3 are used, but a 90-degree reflecting prism 4 is used in order to bring their fields of view closer and parallel. This prism 4 is designed to have a visual field interval i!, taking into consideration the size of the object, the feed speed, etc. In order to be able to adjust this, a device that can move vertically slightly is required, which complicates the configuration. Furthermore, in order to obtain synchronized and equal level signals from the two image sensors 2 and 3, it is necessary to use image sensors with the same characteristics, and it is also necessary to correct unevenness in the illumination system. For this company, this embodiment is a line image sensor i
By using only one device, there is no need to adjust the characteristics of the fine line image sensor or to correct the sensitivity due to uneven illumination, and the device can be made smaller. Furthermore, the amount of visual field shift during installation can be precisely adjusted using a circuit.

As described above, the counting device of the present invention scans the sensor across the moving direction of the object to obtain a binary signal, counts this signal, and counts the binary signal and its predetermined time period. The AND signal with the binary signal of be.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the conventional example, FIG. 2 is a time chart of each part thereof, FIG. 3 is an explanatory diagram explaining the present invention in detail, FIG. 4 is an explanatory diagram of the first embodiment of the present invention, FIG. 5 is a time chart of each part, FIG. 6 is an explanatory diagram showing the scanning state of an object, and FIG. 7 is an explanatory diagram of the second embodiment. DESCRIPTION OF SYMBOLS 1... Belt conveyor, 2.2', 3... Line image sensor, 4... Reflection prism, 5... Target object, 7... Binarization signal part, 8... First counter, 9... signal comparison circuit (AND circuit), 10... second
counter, 11... arithmetic circuit, 12... addition circuit, 18... delay port I circuit, S, S,... binary signal, S3... logical product signal,
N engineering. N2... Count number 2nd table

Claims (3)

[Claims] (1) An optical sensor that detects objects by scanning in a direction transverse to the moving direction of a large number of continuously flowing objects, a binarization circuit that binarizes the output signal of this sensor, and this binarization. a first counter that counts a signal every scan of the line image sensor; and an AND circuit that performs a total AND operation on the binary signal and the binary signal obtained by the binary circuit before a predetermined time. a second counter that counts this AND signal every scan of the line image sensor; an arithmetic circuit that calculates the difference between the count of the 20th counter and the count of the first counter; A counting device equipped with an addition circuit that adds up the results. (2) The sensor has a pair of sensors facing each other and a reflective prism movably arranged between them, and the prism scans in parallel across the entire object at a set interval, and the AND circuit The counting device according to claim 1, characterized in that the binary signals from the pair of sensors are used. (3) The binarized signal of the binarization circuit is supplied to a delay circuit, and the AND circuit receives the binarized signal and the delayed signal of the delay circuit. Counting device as described in section.