JPH0597284A - Surface condition detection for carried medium - Google Patents

Abstract

PURPOSE:To clarify distinction of overlapping of two mediums and wrinkles in a medium by applying an ultrasonic wave pulse to a traveling medium such as a note periodically, and detecting irregularity of the medium from a period until its reflected wave has been received and a weighted output for distance information to the carried medium. CONSTITUTION:In an automatic cash dispenser, there is formed a distance measuring sensor 1 which receives at an electric acoustic wave converting element 3 for receiving, an acoustic wave which is emitted from an electric acoustic wave converting element 2 for transmitting and reflected by a medium 6 while a carried medium 6 such as a note is being transferred, and the outputted signal is inputted into a control part 7. Acoustic wave reflected time between a sensor 1 and the medium 6i s detected at an acoustic wave reflecting time detecting part 10 where the received reflected wave is input after being amplified, and the obtained reflecting time is classified into preset ranks and weighted at a prioritizing part 11. The weighted numerical values are integrated respectively for each transmitted medium at a respective convex part and concave part integrating circuits 13, 14, and the integrated results are compared with respective irregularity margin values to discriminate irregularity of the medium at a medium irregularity discriminating part 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medium carrying mechanism such as a banknote carrying mechanism in an automatic teller machine for detecting a surface state such as wrinkles, folds and tears of a medium carried at a constant speed. Applies to equipment.

[0002]

2. Description of the Related Art Monitoring of medium transportation of a current automatic cash handling apparatus is carried out by detecting medium size, overlapping of two sheets and the like. As a method for detecting them, for example, Japanese Patent Laid-Open No. 57-
A transmitted light sensor as shown in 209585 is used. The transmitted light sensor radiates light from a light source, and the above-mentioned information is detected by fluctuations in the amount of transmitted light due to the bill blocking the light. However, with this method, it is difficult to detect information such as bill skew and fold.

[0003]

In the case of detecting information on a carrier medium by transmitting light as in the transmitted light sensor, it has been difficult to detect information on wrinkles and folds of the medium.

The present invention is difficult to detect by the above conventional method. An object of the present invention is to provide a method of detecting the surface state of a carrier medium, which enables detection of wrinkles and breaks of the carrier medium.

[0005]

In order to achieve the above object, the present invention utilizes a non-contact distance measuring method using sound waves. In this distance measuring method, an electric wave conversion element used as a distance measuring sensor is driven with a constant frequency pulse, a sound wave pulse is emitted into the air, and a sound wave pulse reflected by an object is received by the sound wave electric conversion element. This is a method in which time is measured and the distance between the distance measuring sensor and the object is determined by the time and the sound wave propagation velocity of the medium through which the sound wave propagates. Since the resolution is improved by increasing the driving frequency of the electro-acoustic transducer, in the present invention, a high-frequency electro-conversion element is used to emit a sound wave pulse at a constant cycle in the medium transport path to make the progressive sonic electro-conversion element. The presence or absence of a medium is detected from the received reflected wave, and if there is a medium, the distance to the medium is calculated from the reflected wave reception time, and weighting is performed by distinguishing by a preset rank. Then, the weighted value for each medium is integrated and compared with the integrated value in the case of a medium having no unevenness (reference medium) to determine the surface state of the detection medium.

[0006]

The distance measuring method using sound waves is used to detect the unevenness of the carrier medium.

From the electro-acoustic wave conversion element used as the distance measuring sensor, high frequency pulses are transmitted to the medium carrying path at a constant cycle. When passing through the medium, the acoustic wave pulse is reflected by the medium and is received by the acoustic-electric conversion element. The distance between the medium and the distance measuring sensor can be detected from the reflected wave reception time, and the passage time of the medium can be detected from the number of times the reflected wave is received. The distance obtained from the transport medium is successively distinguished by a preset rank and weighted to a certain numerical value.
Here, the weighted numerical value: N is set as N = 0 when the reference medium (a medium having no unevenness) is detected. Therefore, when the detected medium has irregularities, the weighted numerical value: N is set when the convex portion is detected. N> 0, and the concave portion detection unit has N <0. This weighting value: N is integrated for each state of N> 0 and N <0 by the medium transit time, and its value: Ntp (N> 0 integration value), Ntn (N <0
The surface state of the medium can be detected by comparing the integrated value) with the medium unevenness margin value: ± α.

[0008]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 shows the configuration of the present invention. Carrier Medium-6
Is conveyed at a constant speed in the direction of the arrow in the figure, and the distance measuring sensor unit-1 is attached in parallel with this. In the distance measuring sensor section-1, an acoustic wave transmitting electric wave converting element-2
Is installed so that the transmission sound wave-4 hits the carrier medium-6, and the acoustic wave receiving acoustic-electric conversion element-3 is installed so as to efficiently receive the reflected sound wave-5 from the carrier medium-6, Each is connected to the control unit-7. In the control unit-7, the pulse generation unit-8 generates a high frequency pulse,
The sound wave transmission electric wave conversion element-2 is driven at a constant cycle. The reflected wave receiving unit-9 amplifies the reflected wave received by the sound wave receiving acoustic-electric conversion element-3, and the sound wave reflection time detecting unit-10 amplifies the sound wave between the distance measuring sensor-1 and the carrier medium-6. Detect the reflection time. The sound wave reflection time obtained here is weighted by being classified into a preset rank in the weighting unit-11. (In this embodiment, since the detection distance and the detection sound wave reflection time have a proportional relationship,
For weighting, a value based on the sound wave reflection time at the time of detecting a reference medium (medium having no unevenness) is set for each rank, and the weighting numerical value: N Are divided into convex portions and concave portions of the detection medium according to this. N is integrated for each passing medium in the weighted numerical integration unit-12 by the convex integration circuit-13 and the concave integration circuit-14. (Convex integral value:
N _TP , recessed integral value: N _Tn ) In the medium unevenness determination unit -15, each integrated value: N _TP , N _Tn is preset, medium unevenness margin value: ± α (how many unevennesses are to be detected (Setting value), and as a result, the unevenness of the medium is determined. (Example: N _TP >α; N _Tn <α → Convex twist medium, N _TP <
α; N _Tn > α → concave twisted medium) FIG. 2 shows waveforms at points A, B, and C in FIG. A indicates a drive pulse of the acoustic wave transmitting acoustic wave converting element-2, and B indicates a reflected wave received by the acoustic wave receiving acoustic wave converting element-3. In the figure, 1 and 6 indicate that no reflected wave is received, that is, there is no carrier medium.
5 indicates that the conveyed bill is passing and the reflected wave thereof is received. V _L of the B waveform is a slice level for removing noise and detecting the rising of the reflected wave, and C: the reflected wave detection pulse is created by this V _L , and the sound wave reflection time: t ₂
~ T ₅ is detected.

3 and 4 show a weighting method. Figure 3
, Point A indicates the distance detection position of the reference medium-1,
Points B-1 to 6 indicate distance detection positions of the transport medium-2 having irregularities. FIG. 4 shows transmitted wave-S, A point reflected wave detection pulses, and B-1 to 6 point reflected wave detection pulses. The symbol in the figure: N is a weighted numerical value, N _TP is a convex weighted numerical integration value, and N _Tn is a concave weighted numerical integration value. Before weighting, as shown in FIG. 4, the ranks in which the rising portion of the reflected wave detection pulse of the reference medium-1 is L0 are set in advance at equal intervals from + Ln to -Ln. When the medium-2 having irregularities is detected, the reflected wave detection pulse always fits in the set rank and is weighted according to the rank. (Example: B-1 Part ... Rank: L1 → Weighting: N = n ₁₎ Accordingly protrusions N> 0, the recess is the weighting N <0, the integral value N _TP = n ₃ + n ₄ + N ₁ ,
N _Tn = n ₁ + n ₄ + n ₁ .

[0011]

As described above, according to the present invention, it becomes possible to detect the surface condition such as unevenness of the medium being conveyed at a constant speed, and the number of monitoring items of the medium conveying mechanism such as the automatic cash transaction apparatus increases. , The distinction between the overlapping of two media and wrinkles becomes clear, and the reliability of the apparatus is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of the present invention.

FIG. 2 is a waveform diagram of FIG.

FIG. 3 is a diagram showing a weighted numerical value setting method.

FIG. 4 is a diagram showing a weighted numerical value setting method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Distance measurement sensor part, 2 ... Sound wave transmission electric wave conversion element, 3 ... Sound wave reception sound wave / electric conversion element, 7 ... Control part, 11 ... Weighting part, 12 ... Weighted numerical integration part, 13 ... Medium Unevenness determination part.

Claims (1)

[Claims] 1. A sound wave transmitting element is used to periodically apply an ultrasonic pulse to a medium that is being transported at a constant speed, and the time until the reflected wave is received by the sound wave receiving element and the sound wave propagates. Distance information between the carrier medium and each sonic element obtained from the sound wave propagation velocity of the medium, weighted according to a preset rule, the surface of the carrier medium characterized by detecting the unevenness of the medium from the integrated value State detection method.