JPH0696313A - Paper sheet traveling detector - Google Patents

Abstract

(57) [Abstract] [Purpose] To make it possible to reliably detect the passage of a paper sheet in a stable state by a large number of sensors provided along a paper sheet conveyance path with a simple circuit configuration. is there. [Structure] Light emitting elements A1E to H1E, A2E to H2E,
A3E to H3E and A4E to H4E are sequentially pulse-lighted for a predetermined time t in a time division manner, and light receiving elements A1D to H1D,
By having A2D to H2D, A3D to H3D, and A4D to H4D receive light, and inputting the sensor output signal to the comparators 3a to 3h via the signal lines 2a to 2h, and comparing with a predetermined slice level L, The number of comparators can be reduced by adopting a configuration in which the passage of the bill B is detected. Then, in order to correct the variation in the level of each sensor output signal, the resistance is increased by controlling the switches Sa to Sh which form the switch S, or the voltage addition / subtraction circuit 10 adds + Vcc to the sensor output voltage signal. To -Vcc are configured to be individually added and subtracted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper sheet traveling detecting device for detecting a traveling state of paper sheets in a device for counting paper sheets such as a bill counting device.

[0002]

2. Description of the Related Art For example, there is a bill counting device as a device for transporting paper sheets along a transport path and counting the number of sheets during the transport. This banknote counting device has a hopper into which banknotes are loaded, and the banknotes loaded into this hopper are transferred to the authenticity counter while being transported along a transport path including a transport conveyor.
The denomination, the presence or absence of damage, and the like are discriminated and counted, and each denomination is classified and stored in the stacker. Here, in order to count the banknotes transported along the transport path and monitor whether the banknotes are flowing normally, a sensor for detecting passage of the banknotes is provided at an appropriate position of the transport path. . This sensor is usually composed of a light emitting element and a light receiving element, and the light emitting element is always made to emit a constant amount of light, and when the optical path from the light emitting element to the light receiving element is blocked by the bill, the bill passes through. I am trying to detect. By the way, since relatively thin paper such as banknotes transmits light to some extent, a signal is output from the light receiving element even when the banknotes pass through. Therefore, the passage of the bill is not detected by the presence or absence of the output of the light receiving element, but is detected by the level of the output signal. For this reason, the light receiving element is connected to the comparison means, and the comparison means is used. The passage of bills is detected by comparing the output signal of the light receiving element with a preset slice level.

[0003]

By the way, in the case where the conveyance path of paper sheets made of bills and the like is long and complicatedly bent, and there is a branch path or a transition portion from one conveyance section to another conveyance section. In that case, a large number of sensors must be provided. When a large number of sensors are provided in this way, if a corresponding number of comparison means are provided, the number of parts becomes enormous, which complicates the circuit configuration and also increases reliability. become worse.

The present invention has been made in order to solve the above-mentioned drawbacks and problems of the prior art. The purpose of the present invention is to ensure a stable passage of paper sheets with a simple circuit structure. It is an object of the present invention to provide a paper sheet traveling detection device capable of detecting the paper sheet.

[0005]

In order to achieve the above-mentioned object, according to the present invention, light receiving elements in a plurality of paper sheet passage detection sensors are connected, and output voltage signals from these light receiving elements are time-divided. Comparing means for taking in the comparing means and comparing with a predetermined slice level, and voltage adjusting means for adjusting the voltage of the output signal from each light receiving element, and a configuration for correcting the level difference of the output signal in each of these light receiving elements. It is characterized by having done.

[0006]

When a large number of sensors provided on the paper path are individually connected to the comparator, the structure of the banknote traveling monitoring mechanism becomes extremely complicated. Therefore, the light receiving elements of a plurality of sensors are connected to a single comparing means, and these sensors are operated repeatedly in a time-divisional manner at predetermined time intervals, and the output signals from the light receiving elements of these sensors are timed. It is configured so that it is sequentially taken into the comparing means and sequentially compared with the slice levels set in the comparing means. By this, compared to the number of sensors,
The number of comparison means can be significantly reduced.

However, in order to compare the output signals from a plurality of light receiving elements with a preset slice level by a single comparing means, the light receiving amounts of all the light receiving elements must be the same. However, in order to reduce the size of the device, the paper path is complicatedly bent, and when the sensor installation space is limited due to the relationship with other members, the light emitting element and It is not always possible to place the light receiving element in a fixed positional relationship. As a result, for example, the output signal level of the light receiving element of one sensor when the sheet is detected becomes higher than the output level of the other sensor when the sheet is not detected, and there is almost no difference from the slice level. This means that the paper sheet cannot be accurately detected in a stable state, such as when the paper is lost.

From the above, the voltage adjusting means adjusts the variation in the output signal level of each sensor connected to each comparing means. That is, the voltage level of the output signal from the light receiving element of the sensor which outputs a high level signal is lowered, and in the light receiving element which outputs a low level signal, the voltage is added and the level is changed. To raise. As a result, the signal levels from a plurality of connected light receiving elements become constant, the paper sheet passage detection accuracy is improved, and the paper sheet can be reliably detected in an extremely stable state.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows a first embodiment of the present invention. In the figure, A1 to H1, A2 to H2, A3 to H3, A4
H4 indicate eight sets of four light-transmissive sensors, each of which is arranged at an appropriate position in the middle of the conveyance path R of the bill B. The light emitting elements A1E to H1E, A2E to H2E, A3 in the sensor consisting of 32 pieces
E to H3E and A4E to H4E are light receiving elements A1D to H1D, A2D to H2D, A3D to H3 at predetermined intervals.
D, A4D to A4H are faced (in the drawings, some of the sensors are omitted for simplification).

The sensors A1 to H1, the sensors A2 to H2, the sensors A3 to H3, and the sensors A4 to H4 are individually connected to the light emission drive circuits 1a to 1d, and one set is formed by the light emission drive circuits 1a to 1d. At the same time,
The light emitting operation is performed in a time division manner. That is, first, the light emitting elements A1E to H1E are lit for a predetermined time t, and then the light emitting elements A2E to H2E, the light emitting elements A3E to H3E,
The light emitting elements A4E to H4E are sequentially turned on for a time t, and this operation is sequentially repeated. Further, among the 32 light receiving elements, the light receiving elements A1D to A4D and the light receiving element B
1D to B4D, light receiving elements C1D to C4D, light receiving element D1
D to D4D, light receiving elements E1D to E4D, light receiving element F1D
To F4D, light receiving elements G1D to G4D and light receiving element H1D
.About.H4D are connected to four comparators 3a to 3h via signal lines 2a to 2h, respectively. Accordingly, it is sufficient to provide eight comparators, which is a quarter of 32 sensors, for the 32 sensors, the number of comparators can be significantly reduced, and the circuit configuration can be simplified.

Next, reference numeral 4 denotes a sensor control circuit, which is a light emission drive circuit 1a.
.About.1d, while giving a predetermined slice level L to the comparators 3a to 3h and comparing the output signal from each light receiving element with this slice level L, whether the bill B has passed the position of each sensor. It is determined whether or not. The result of this determination is taken into the register 5 and held until the next data is input. A microcomputer 6 is connected to the register 5, and the microcomputer 6 monitors the traveling state of the banknotes B and counts the number of the banknotes B conveyed to the conveyance path R. It is configured.

Here, the slice level L input from the sensor control circuit 4 to the comparators 3a to 3h is common to all. Therefore, in order to detect the bill B based on the output signals from the comparators 3a to 3h, the output voltage signals of all the light receiving elements in the 32 sensors must be at the same level. That is, the levels of the output voltage signal when the bill B does not pass must be the same, and the levels of the output voltage signal from the light receiving elements when the bill B does not pass must also be the same.
However, it is impossible to make all the distances between the light emitting element and the light receiving element the same from the viewpoint of the installation location, the assembling accuracy and the like. Therefore, it is necessary to correct this sensor output signal. In order to correct this output signal, the terminating resistor TT connected to each of the signal lines 2a to 2h
The additional resistance TA is connected in parallel with the additional resistance TA, and the additional resistance TA is grounded via the switches Sa to Sh that form the switch S. Therefore, the switches Sa to Sh
When any of the above is closed, the resistance in the signal line becomes the terminating resistance TT and the additional resistance TA, and the resistance value increases, whereby the voltage level of the sensor output signal transmitted through the signal line. Will be reduced. The switching control of the switch S is performed based on the signal from the sensor control circuit 4.

The present embodiment is constructed as described above, and its operation will be described below. Then, the sensor control circuit 4 is operated to activate the light emission drive circuit 1a.
A driving signal is applied to the light emitting elements A1E to H1E from 1d to 1d, and pulse lighting is performed for a predetermined time t. Then, the corresponding light receiving elements A1D to H1D receive this light,
This sensor output signal is input to the comparators 3a to 3h via the signal lines 2a to 2h and compared with the slice level L from the sensor control circuit 4. If the sensor output signal is higher than the slice level L, it means that the bill B has not passed, and if the level of the sensor output signal is lower than the slice level L, the bill is located at the position where the sensor is arranged. It is detected that B is passing. Then, a drive signal is applied to the sensors A2 to H2,
The light emitting elements A2E to H2E are turned on, and this light is received by the light receiving element A.
The light is received by 2D to H2D, the sensor output signal is input to the comparators 3a to 3h, and it is detected whether or not the bill B has passed the position of the sensor. And the light emitting element A
Output signals from the light receiving elements A3D to H3D are input to the comparators 3a to 3h by turning on the light emitting elements 3E to H3E, and further the light emitting elements A4E to H4E are turned on and the light receiving elements A4D to H4.
The output signal of D is input to the comparators 3a to 3h and compared with the slice level L, so that the bill B
Is detected. Then, the bill passage detection signal is taken into the register 5 and held until the next detection signal is input by the register 5. Therefore, during this period, the microcomputer 6 reads the data of the register 5 and performs a predetermined signal processing,
It is possible to monitor the traveling state of the bill B and to count the number of bills.

Now, for example, the light emitting element A in the sensor A1
It is assumed that the distance between 1E and the light receiving element A1D is shorter than the distance between the light emitting element and the light receiving element of another sensor.
In this case, the voltage level of the light receiving signal by the light receiving element A1D of the sensor A1 becomes higher than that of the other sensor. Therefore, if the sensor output signal of the other sensor is compared with the same slice level, Even when passing, the level of the output signal from the light receiving element A1D is equal to that of the comparator 3
The margin with respect to the slice level L in a becomes extremely small, or in the extreme case, it becomes higher than the slice level L. Therefore, the sensor control circuit 4 stores the data in advance, and when the drive signal is input from the light emission drive circuit 1a to the sensors A1 to H1 by the control signal from the sensor control circuit 4, the sensor control circuit 4 outputs the data. A switch drive signal is input to the switch S from 4 to close the switch Sh.
As a result, the resistance in the signal line 2a increases by the additional resistance TA, the voltage level of the output signal from the light receiving element A1D decreases, and the voltage level of the output signal of the other sensor is corrected to substantially match. . As a result, even if the intervals of the light emitting elements and the light receiving elements of all the sensors provided in large numbers do not match, there is no problem in detecting the bill B.

Next, FIG. 2 shows a second embodiment of the present invention. In FIG. 2, the same or equivalent members as those in FIG. 1 are designated by the same reference numerals and their description is omitted. . Thus, in this embodiment, the output signal levels of the 32 sensors A1 to H4 can be adjusted steplessly. That is, in the figure, 10 indicates a voltage adding / subtracting circuit, which is composed of a selector 11 and a D / A converter 12, and which outputs + V to the output voltage signal transmitted via the signal lines 2a to 2h.
The voltages in the range from cc to -Vcc can be added individually. The voltage to be added is preset in the memory 13 in the voltage addition / subtraction circuit 10, and the data regarding the added voltage value set in the memory 13 is transferred to the selector 11 in the voltage addition / subtraction circuit 10.
Then, the D / A converter 12 can add and subtract the voltage to and from the sensor output signal. For this reason, the D / A converter 12 has wirings 14a to 14h.
Are connected to the wirings 14a to 14h, and the wirings 14a to 14h are connected to the diode D and the comparators 3a to 3 in the signal lines 2a to 2h, respectively.
It is connected to the position between h and h.

As described above, it is extremely difficult for the sensors A1 to H4 arranged along the conveyance path R to keep the distance between the light emitting element and the light receiving element constant, and the sensors emit light. Since there are variations in the quality of the elements and the light receiving elements and deviations of the optical axis during assembly, there are generally considerable variations in the level of each sensor output signal. Therefore, in order to detect the bill B with higher accuracy, it is preferable to individually correct the voltage level of the output signal of each sensor. From the above, in the present embodiment, the voltage level of the output signal of the light receiving element in each sensor is actually detected, the correction value is determined and the memory is stored in advance.
A correction value is set in 13, and when the bill B is detected, the correction value is read from the memory 13 and each sensor output signal is corrected individually. This makes it possible to reliably detect the bill B in an extremely stable state.

Therefore, the setting of the correction value will be described first. The power is turned on, the sensor control circuit 4 is operated, the sensors A1 to H1 are simultaneously driven, the light emitting elements A1E to H1E are turned on, and the light is received by the light receiving element A1D.
Let H1D receive light. Then, the voltage level of the output signals from the light receiving elements A1D to H1D is subtracted by the voltage adding / subtracting circuit 10, the signals are taken into the comparators 3a to 3h, and the slices are given to the comparators 3a to 3h. The output voltage level of the voltage adder / subtractor circuit 10 when the outputs of the comparators 3a to 3h are inverted is compared with the level L and is fetched into the microcomputer 6. by this,
The deviations of the light receiving elements A1D to H1D from the slice level L are individually detected. These sensors A1 to H
When the detection of the deviation of the sensor output signal from the slice level L in 1 is completed, the sensor control circuit 4 drives the sensors A2 to H2, and the slice level of the sensor output signals of the sensors A2 to H2 is driven in the same manner as described above. The deviation with respect to L is detected, and then the deviation with respect to the slice level L of the sensors A3 to H3 and the sensors A4 to H4 is sequentially detected.

As described above, after the deviation of the sensor output signal from the slice level L when all the bills B of the 32 sensors including the sensors A1 to H4 do not pass is detected individually, the light of the bill B is detected. From the relationship with the transmittance of the above, the microcomputer 6 individually determines a correction value for each sensor so that a predetermined optimum sensor output signal can be obtained. Then, the correction value thus determined is stored in the memory 13. This completes the setting of the correction value.

Therefore, the apparatus is operated to actually flow the bill B on the conveyance path R, and the sensors A1 to H1 and the sensors A2 to H2 are controlled by the control signal from the sensor control circuit 4.
The sensors A3 to H3 and the sensors A4 to H4 are sequentially and repeatedly driven for a predetermined set time t to receive the light receiving elements A1D to H1.
D, light receiving elements A2D to H2D, light receiving elements A3D to H3D
When the sensor output signals from the light receiving elements A4D to H4D are sequentially input to the comparators 3a to 3h via the signal lines 2a to 2h, the correction values are sequentially added from the memory 13 to the voltage adding / subtracting circuit 10.
Is taken into the selector 11 and the correction voltage is supplied by the D / A converter 12 to be added / subtracted to the actual sensor output signal.

That is, as shown in FIG. 3, the voltage level of the output signal from the light receiving element when the bill B is not passing has a waveform as shown in the waveform diagram (a) in the figure, and the bill B is
Assuming that the voltage level of the output signal from the light receiving element at the time of passing the signal has the waveform shown in the waveform diagram (b),
By performing the correction for subtracting the voltage level of the sensor output signal by the correction value shown in the waveform diagram (c), the difference between the banknote B and the slice level L when the bill B is not passed and when the bill B is passed is a waveform diagram (d). , (E), the detection margins of all the sensors can be sufficiently provided, and the passage of the bill B can be reliably detected in an extremely stable state.

In each of the above-mentioned embodiments, 32
Although the number of the sensors is used, the number of the sensors is not limited to this. For example, when 64 (8 × 8) sensors are provided, the number of sensors is 8 in the signal line connected to the comparator.
The sensors may be connected individually.

[0022]

As described above, according to the present invention, the light receiving elements of a plurality of sensors are connected to a single comparing means, and the output voltage signals from the respective light receiving elements are fetched into the comparing means in a time division manner. Since it is configured to compare with a predetermined slice level, the number of comparison means can be significantly reduced compared to the number of sensors, and the circuit configuration of the paper sheet traveling monitoring mechanism is simplified. In addition, the voltage adjusting means adjusts the voltage of the output signal from each light receiving element, and the voltage adjusting means corrects the level difference of the output signal in each light receiving element. With extremely stable passage of leaves,
Can be accurately detected.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a paper sheet traveling monitoring device showing a first embodiment of the present invention.

FIG. 2 is a circuit configuration diagram of a paper sheet traveling monitoring device showing a second embodiment of the present invention.

FIG. 3 is a waveform diagram of the sensor output signal of FIG. 2 and its correction signal.

[Explanation of symbols]

A1 to H1, A2 to H2, A3 to H3, A4 to H4 Sensors A1E to H1E, A2E to H2E, A3E to H3E, A
4E-H4E Light emitting elements A1D-H1D, A2D-H2D, A3D-H3D, A
4D-H4D Light receiving element 1a-1d Light emission drive circuit 2a-2h Signal line 3a-3h Comparator 4 Sensor control circuit 5 Register 6 Microcomputer 10 Voltage addition / subtraction circuit 11 Selector 12 D / A converter 13 Memory 14a-14h Wiring B Banknote R transport path

Claims (4)

[Claims] 1. A plurality of sensors for detecting passage of a paper sheet, which are composed of a light emitting element and a light receiving element, are arranged along a conveying path such as a conveyor, and the passage of the paper sheet is detected based on signals from these sensors. In the one to be detected, the light receiving elements in the plurality of sensors are connected, the output voltage signals from the respective light receiving elements are time-divisionally captured in a comparator and compared with a predetermined slice level, and the light receiving elements from the respective light receiving elements are compared. A paper sheet traveling detection device comprising: voltage adjusting means for adjusting the voltage of an output signal, and the voltage adjusting means is configured to correct the level difference between the output signals of the respective light receiving elements. 2. The voltage adjusting unit controls a resistor connected in parallel with a terminating resistor provided in a signal transmission cable from each of the light receiving elements to the comparing unit, and controls whether or not the resistor is added to the terminating resistor. The paper sheet traveling detection device according to claim 1, wherein the traveling detection device comprises a switching means. 3. The paper sheet traveling detection device according to claim 1, wherein the voltage adjusting means is composed of voltage adding / subtracting means for adding / subtracting the voltages of the output signals of the respective light receiving elements. 4. The configuration according to claim 2, wherein the level difference is corrected by the voltage adjusting unit individually for each sheet detection sensor by actually passing the sheet. Item 3. A paper sheet traveling detection device.