JPS6030618B2 - Paper sheet double feed detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper sheet processing device, and more particularly to a double feed detection device for paper sheets.

Conventionally, in this type of double-feed detection, a curved suction section is provided on one side of the conveyance path, and one of the paper millets passing through the two piles is sucked by the suction section and sent to the normal conveyance path in the curved direction. Another method is to send the other one to the straight-line removal conveyance path without being affected by the suction part, or to use rollers with different rotational speeds as part of the conveyance system, and to use paper processing in front of and behind the rollers. A system was adopted in which a change in the length from the leading edge to the trailing edge of the forehead was detected, and if there was a change, it was determined that two copies of medicine should be sent and the paper medicines were sent to the removal conveyance path.

However, these conventional systems have drawbacks such as large noise generated from the intake section and complicated mechanisms. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a simple and low noise double feed detection device.

According to the present invention, a conveyance path composed of two belts;
It consists of a refraction section provided in the middle of the conveyance path, a space created by separating the two belts that make up the conveyance path at the refraction section, and a light emitter and a light receiver, and has an optical axis in a direction that crosses the conveyance path. The device is composed of a first paper sheet detector that detects paper sheets passing through the space, a light emitter that emits light onto the paper sheets in the space, and a light receiver that receives the reflected light, and detects paper sheets that pass through the space. A double-sheet feed detection device is obtained, which includes a second paper sheet detector that detects double-sheet feeding, and a processing circuit that compares outputs from the first and second paper medicine detectors to detect double-sheet feeding. The present invention will be described in detail below with reference to the drawings of one embodiment of the present invention.

FIG. 1 is a diagram showing an embodiment of the present invention, in which a conveyance path consisting of two belts 13a and 13b has a bending point, and the belt outside the bending point is designed so as not to restrict the paper sheets passing through. A void is created away from the inner belt. One pair of optical receivers 11a and 12a of the two sets of transmitter/receivers are installed with their light beams crossing the conveyance path in order to detect the presence or absence of paper sheets passing through this bending section.

Of the other pair of light receivers 11b and 12b, the light emitter 11b is set so that its light enters the conveyance path in the vicinity of the bending point obliquely and reaches the paper hollyhock passing through.
2b is arranged so as to receive the light scattered and reflected on the surface of the paper sheet through the gap. At this time, the width of the belt constituting the conveyance path is set to be 4 mm wider than the minimum width of the paper hollyhock, and the light beam created by the optical receiver is not blocked by the belt, but the paper hollyhock is projected in a position that allows it to be detected. Layout the receiver.
The paper sheet that has entered the bending section from the conveyance path 15a passes through the gap, peels off from the belt 13b until it reaches the belt 13a, and then advances linearly in the direction of extension of the conveyance ball 15a. It is guided by the belt 13a and sent to the conveyance path 15b.

At this time, the tip of the paper bag is incident on the light receiver 12b through the conveyance path 15.
It begins when point b is reached and ends when the end passes through the bend. The incidence on the light receiver 12a ends just before the tip of the paper towel reaches the belt 13a, and starts again when the tip ends passing through the bending section. Figure 2 is a diagram showing this situation, and when paper millets are transported one by one,
While the output A from the receiver 2a is interrupted once, the output from the receiver 12b is output only once, but as shown in FIG. 1, two sheets 14a and 14b overlap. When the paper sheet ida is transported, the output A of the light receiver 12a is interrupted once while the output B' of the light receiver 12b is interrupted once by the leading edge of the paper sheet ida, so that the output is divided into two. Therefore, the states of the outputs A and B of the two light receivers 12a and 12b are determined, and in the latter case, a signal C is output from the processing circuit.
FIG. 3 is a diagram showing an example of the configuration of the above-mentioned processing circuit,
It is composed of an inverter 16 that inverts the signal A, a detector blade 7 that receives the signal B and detects the fall of the signal, and a gate 18 that takes the logical logic of the signal A and the output of the detector 17. The output is the double detection signal.

Furthermore, if the light emitter and receiver are arranged as shown in Fig. 4, the end of the paper medicines passing through the bending part will block the light entering the light receiver, and the paper medicines 14a, which are transported in duplicate, Double feeding can also be detected when the mutual longitudinal positional relationship of the sheets 14b is opposite to that shown in FIG.

As described in detail above, according to the present invention, a simple and low-noise two-way detection device can be obtained.

Brief Explanation of the Drawings Figure 1 is a diagram showing one embodiment of the present invention, Figure 2 is a diagram showing a signal waveform from the light receiver in Figure 1, and Figure 3 is a diagram showing one embodiment of the processing circuit.
FIG. 4 is a diagram showing a second embodiment of the present invention.

In the figure, Kagome a, ]lb... Floodlight, 12a, 12
b...Receiver, 13a, 13b...Belt, 14a
, 14b... paper sheets, turtle 5a, oven 50... conveyance path,
Tortoise 6...Inverter Quantity 7...Fall detection circuit, ]8...Gate. Figure 1 Figure 3 Figure 2 Figure 4

Claims (1)

[Claims] 1. A conveyance path that is composed of two belts and conveys paper sheets while sandwiching them; a bending section provided in a part of the conveyance path; and a space created by separating the two belts from each other at the bending section; a first paper sheet detector that is composed of a light emitter and a light receiver, has an optical axis in a direction that crosses the conveyance path, and detects paper sheets passing through the space; and a light emitter that emits light onto the paper sheets that come into the space. and a light receiver that receives the reflected light, and a first paper detector detects the paper by receiving the outputs of the first and second paper detectors. and a processing circuit that outputs a double-feeding detection signal when the second sheet detecting device detects a plurality of times when the second sheet is being detected. Detection device.