JP2707665B2 - Paper chip detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention detects a paper piece attached to a letter, for example, an end of a stamp or an address label, and measures the position and size of the paper piece. It is about.

[Conventional technology]

In the case of automatically processing letters such as mail,
It may be necessary to measure the position and size of a piece of paper such as a stamp or address label attached to the letter,
A paper chip detecting device is used for the measurement.

Conventionally, in this type of sheet detecting apparatus, the end of the sheet is detected by optically measuring the difference in color and reflectance between the sheet and the surrounding letter surface, and measuring them. The position and size were measured.

[Problems to be solved by the invention]

By the way, there are various types of letters and paper pieces to be handled, and the color and the reflectance are not always constant. Therefore, in the above-described conventional paper piece detection device, the detection is made depending on the color and the reflectance of the paper and the letter. There is a drawback that it may not be performed well.

The present invention has been proposed in view of the above points, and its object is to be able to accurately detect the end of a paper sheet without being affected by the color or reflectance of the paper sheet or letter. An object of the present invention is to provide a paper sheet detecting device.

[Means for solving the problem]

The present invention, in order to achieve the above object, a light projecting unit that irradiates a single-phase light beam to a piece of paper attached to a letter conveyed in one direction, and a light receiving unit that receives light reflected from the piece of paper, An information processing unit for observing the state of diffraction of the reflected light from the received light signal and determining whether or not the end of the paper sheet is at a predetermined pitch in a direction perpendicular to the conveying direction of the letter. A paper piece position calculation unit that calculates the size of the paper piece attached to the letter based on the determination result of each of the detection devices and the transport speed of the letter, and has a configuration in which a plurality of pieces are arranged in a line. I am preparing for it.

[Action]

In the paper piece detection device of the present invention, the light emitting unit of the detection device irradiates a single-phase light beam to the paper piece attached in a letter conveyed in one direction, and the light receiving unit reflects from the paper piece. Received light beam, the information processing unit observes the state of diffraction of the reflected light from the received light signal to determine whether or not the end of the paper piece, the paper piece position calculation unit, the determination result of each detection device and The size of the piece of paper pasted on the letter is determined based on the letter transport speed.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a paper piece detecting device according to the present invention. In FIG. 1, reference numeral 1 denotes a letter, and reference numeral 2 denotes a piece of paper to be detected and attached to the letter 1. The letter 1 is conveyed at a predetermined speed in the direction of the arrow by a conveying mechanism (not shown). On the other hand, 3A, 3B, 3C,... Are detection devices, and a plurality of detection devices are arranged in a line in a direction perpendicular to the conveying direction of the letter 1, and each of the detection devices 3A, 3B, 3C.
The output signals (determination results) of C,... Are input to the sheet position calculating unit 4. This embodiment shows a configuration for measuring the position and size of the paper piece 2 two-dimensionally. Therefore, a plurality of detection devices 3A, 3B are arranged in a direction perpendicular to the conveying direction of the letter 1. , 3C,... Are arranged in a line.

The internal configuration of the detecting devices 3A, 3B, 3C,... Will be described later.
C,... A predetermined measurement point (point irradiated with irradiation light) immediately below is a piece of paper 2.
Is sent out to indicate whether or not it is approaching the end of the. Then, the sheet position calculating unit 4 is configured to detect each of the detecting devices 3.
A signal indicating the end of the sheet 2 is received from A, 3B, 3C,... For example, assuming that the sheet 2 passes under the detecting devices 3B, 3C,... With the transport of the letter 1, the detecting devices 3B, 3C,. Is the length (size) of the paper piece 2 in the transport direction.
.. Of the detection devices 3A, 3B, 3C,... Multiplied by the arrangement pitch of the detection devices 3A, 3B, 3C,. 2 length. The position of the paper piece 2 is the letter 1 in the transport direction.
Can be represented by the distance from the reference point to the ends on both sides of the paper sheet 2. In the direction perpendicular to the transport direction, it can be represented by the detection device from which the signal indicating the end is obtained. .

FIG. 2 shows the internal configuration of one of the detection devices 3A, 3B, 3C,... In FIG. In FIG. 2, the detecting device includes a light projecting unit 31 for irradiating a single-phase light beam (irradiation light L1) to a paper piece 2 attached to a letter 1 conveyed in one direction, and a light beam reflected from the paper piece 2. A light receiving unit 32 that receives the (reflected light L2), and information processing for observing the state of diffraction of the reflected light L2 from the light receiving signal photoelectrically converted by the light receiving unit 32 and determining whether or not the light is the end of the sheet 2 Part 33 is included.
Note that a laser light source is used as the light projecting unit 31 to obtain the single-phase irradiation light L1, and a CCD that can select a detection position to detect the state of diffraction of the reflected light L2 is used as the light receiving unit 32.
Is used.

The principle of detecting the end of the paper sheet 2 in the detection device is as follows. That is, when the irradiation light L1 is incident on the flat portion of the paper piece 2 as shown in FIG. 2, the reflected light L2 is also transmitted to the light receiving section 32 in a substantially straight line because the portion reflecting the irradiation light L1 is relatively smooth. The incident light and the light receiving intensity with respect to the position of the light receiving section 32 are simple as shown in FIG. On the other hand, when the irradiation light L1 is incident on the end of the paper piece 2 as shown in FIG. 3, the diffraction phenomenon strongly acts on the reflected light L2 based on the irregularity of the end, and the reflected light in a scattered state is reflected. Since the light L2 is incident on the light receiving portion 32, the light receiving intensity at the position of the light receiving portion 32 becomes complicated as shown in FIG. Therefore, by measuring the disturbance of the light receiving intensity of the light receiving unit 32 with respect to the position, it can be determined whether or not the end of the paper sheet 2 is present.

FIG. 4 shows the configuration of the information processing section 33 in FIG. 2. The Fourier transform (finite section Fourier transform) is performed on the light receiving signal of the light receiving section 32 to detect a disturbance in the received light intensity with respect to the position. Like that. In FIG. 4, the information processing unit 33 includes a Fourier transform unit 331 for performing a Fourier transform on the light receiving signal of the light receiving unit 32, a peak detecting unit 332 for detecting a peak value of an output signal of the Fourier transforming unit 331, and a peak detecting unit 332. And a determination unit 333 that determines whether or not it is the end of the sheet 2 based on the peak value obtained in step (1).

FIG. 5 is a more specific configuration diagram of FIG.
The conversion unit 334, the memory 335, and the FFT processing unit 336 correspond to the Fourier transform unit 331 of FIG. 4, the peak detection unit 337 corresponds to the peak detection unit 332 of FIG. 4, and the determination unit 338 determines the determination of FIG. It corresponds to the unit 333. Reference numeral 339 denotes a timing controller that controls the timing of A / D conversion and FFT.

FIGS. 8 and 9 show Fourier transform results corresponding to the distribution of the received light intensity in FIGS. 6 and 7, respectively. Although only a single peak appears as shown in the figure, in the case of the received light signal at the end, two or more peaks appear as shown in FIG.
The number of peaks and the peak level are obtained by the peak detection units 332 and 337, and the determination units 333 and 338 comprehensively determine them to determine whether or not the end of the paper sheet 2 is present.

〔The invention's effect〕

As described above, in the paper piece detecting apparatus of the present invention, since the end of the paper piece is detected from the state of diffraction of the reflected light based on the irregularity of the end of the paper piece, the paper piece, the letter There is an effect that the end portion can be reliably detected regardless of the color or reflectance.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a paper piece detecting device of the present invention, FIG. 2 is a configuration diagram of the detection device in FIG. 1, FIG. 3 is a diagram showing a detecting operation at an end of the paper piece, FIG. FIG. 5 is a configuration diagram of the information processing unit in FIG. 2, FIG. 5 is a specific configuration diagram of the information processing unit in FIG. 4, FIG. FIG. 8 is a diagram showing the received light intensity at the end of the sheet, FIG. 8 is a diagram showing the Fourier transform result at the flat portion of the sheet, and FIG. 9 is a diagram showing the Fourier transform result at the end of the sheet. In the figure, 1 ... letter 2 ... paper piece 3A, 3B, 3C ... detecting device 31 ... light emitting unit 32 ... light receiving unit 33 ... information processing unit L1 ... irradiation light L2 ... reflected light 331 ... Fourier transform section 332 ... Peak detecting section 333 ... Determining section 334 ... A / D converting section 335 ... Memory 336 ... FFT processing section 337 ... Peak detecting section 338 ... Determining section 339 ... Timing controller 4 ... … Paper piece position calculator

Claims (1)

(57) [Claims] 1. A light projecting unit for irradiating a single-phase light beam to a paper piece adhered to a letter conveyed in one direction, a light receiving unit for receiving a light beam reflected from the paper sheet, and a reflected light from a light receiving signal. And an information processing unit that determines whether or not the end of the paper piece by observing the state of diffraction of the paper letter, a plurality of lines in a row at a predetermined arrangement pitch in a direction perpendicular to the conveying direction of the letter. It has a configuration in which it is arranged, and further comprises a paper piece position calculation unit that calculates the size of the paper piece attached to the letter based on the determination result of each of the detection devices and the transport speed of the letter. Paper piece detecting device.