JPH02175541A - Detecting device for thickness of paper sheet - Google Patents

Abstract

PURPOSE:To enable the correct detection of the thickness of the paper sheets by forming a device so as to judge the adhesion of the foreign material on a reference roller and remove that foreign material when the detected data exceeds the reference data more than the predetermined value. CONSTITUTION:The reference data showing the displacement quantity of a detecting roller 2 to the surface position of a reference roller 1 is previously created, and in the time zone when a device is operated and the bill is not carried, the displacement quantity of the detecting roller 2 to the surface position of the reference roller 1 is detected to be compared to the created reference data, and when the change more than the predetermined value is detected, the adhesion of the foreign material on the reference roller 1 is judged. A scraper 7 is located facing to the reference roller 1, and when the adhesion of the foreign material is judged by a control unit, the control unit drives a solenoid 9 through the driver, and the scraper 7 is adhered to the reference roller 1 to remove the foreign material.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is directed to a paper sheet that detects the thickness of a banknote being conveyed, for example, in a banknote inspection device used in an automatic teller machine. This invention relates to a type of thickness detection device.

(Prior art) For example, as in a bill inspection device, a bill 1 being conveyed
Detecting the thickness of a banknote is also an important item in a device that reads the information contained in each banknote.

The thickness detection device for this purpose is used to determine whether a single banknote is being conveyed or whether there is no tape attached to it, and it is configured as follows. ing.

In other words, by bringing a movable detection roller into contact with a reference roller that is used as a standard for thickness measurement, and passing a banknote conveyed by a conveyor belt between these two rollers, the thickness of the banknote being detected is detected. The amount of displacement of the roller is converted into an electrical signal using, for example, a color displacement sensor, and the electrical signal determines whether there is one bill, a bill with tape attached, or two or more bills. This is to determine the

However, in the conventional thickness detection device configured as described above, detection is performed assuming that the reference roller O reference surface and the circumferential surface of the detection roller do not change and are constant. If a foreign object such as dust adheres to the surface of the banknote, the thickness of the banknote (paper sheet) determined by the thickness detection device using the reference roller or detection roller will be the thickness of the foreign object. This has the disadvantage that the actual thickness cannot be detected correctly.

(Problems to be Solved by the Invention) As described above, the present invention provides a thickness detection device that uses the reference roller or the detection roller when foreign matter such as dust adheres to the surface of the reference roller or the detection roller. ,
This was developed to eliminate the drawback of not being able to accurately detect the thickness of paper sheets. Even if foreign matter such as dust adheres to the surface of the reference roller or detection roller, the thickness of paper sheets can be detected correctly. The purpose of this invention is to provide a device for detecting the thickness of paper sheets.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above-mentioned problems, the paper sheet thickness detection device of the present invention has the following features: a reference roller that serves as a standard for measuring thickness, and this reference roller. The paper sheet to be measured is sent between a variable detection roller that comes into contact with the sheet, and the thickness of the sheet is detected by converting the amount of variation in the detection roller into an electrical signal. The detection device includes a paper sheet detection means for detecting that there is no paper sheet between the reference roller and the detection roller, and a paper sheet detection means for detecting that there is no paper sheet between the reference roller and the detection roller. a comparison means for converting the amount of variation of the detection roller into an electric signal and comparing the detected data with reference data when it is detected that the detection roller does not exist; a determining means for determining that foreign matter is attached to the reference roller when the temperature exceeds a predetermined value; and a removing means for removing the foreign matter from the reference roller when the foreign matter is detected as a result of the determination by the determining means. It is characterized by having the following.

(Function) With the above-described configuration, when the paper sheet detecting means first detects that there is no paper sheet between the reference roller and the detection roller, the present invention detects the amount of displacement of the detection roller by an electric signal. to obtain detection data.

Next, this detection data is compared with reference data, and it is determined whether a foreign object is attached to the reference roller based on whether or not there is a difference of more than a predetermined value between them.

Based on the result of this determination, if foreign matter is attached to the reference roller, the removing means is driven to remove the foreign matter from the reference roller.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. In FIG. 1, 1 is a base crawler that serves as a reference for measurement, 2 is a detection roller that contacts the base with the displacement amount on the roller, 3 is an angular displacement sensor that converts the displacement amount of the detection roller 2 into an electrical signal, Reference numeral 4 denotes a banknote as an object to be measured, and 5 a conveyor belt that clamps and conveys the banknote 4.

When the banknote 4 held between the reference roller and the detection roller 2 by the conveyor belt 5 is conveyed in the direction of the arrow shown in the figure, the banknote 4
The detection roller 2 moves up and down depending on the thickness of the detection roller 2, and the angular displacement sensor 3 outputs a voltage corresponding to the amount of movement of the detection roller 2.

Further, 6 indicates a banknote 4 between the reference roller and the detection roller 2.
This is a sensor that detects whether or not there exists.

FIG. 2 is a block diagram of the electric circuit of this embodiment.
is an amplifier 22 that amplifies the output signal of the angular displacement sensor 3;
11 is an A/D converter that converts the analog signal output from the amplifier 9 into a digital signal 11, and 11 is a counter that counts the digital signal output from the A/D converter 10 and holds the displacement amount of the detection roller 2 as a digital value. It is. Further, 24 is a detection circuit which detects whether or not a banknote 4 exists between the reference roller 1 and the detection roller 2 in response to the detection signal fl° from the position sensor 6, and detects whether or not a banknote 4 is present. When detected, a signal indicating this is sent to the control section 26. Further, 26 is a motor that drives the reference roller 1 to rotate □, and 27 is a driver that drives the motor 27.

The control unit 28 uses a microcomputer, for example, from t1 to
It is designed to control the entire device.

That is, it reads the output value of the counter 23 to recognize the amount of displacement of the detection roller 2, receives a detection signal from the detection circuit 24 and performs corresponding processing, and performs various other controls. Reference numeral 29 is a storage unit that stores a control program for operating the microcomputer of the control unit 28, data necessary for processing, first reference data, second reference data, etc. to be described later. Further, the display unit 30 displays the status of the device, messages from the device, and the like.

Next, the operation in the above configuration will be explained. First, by cleaning the reference roller 1 and the detection roller 2, it is confirmed that no foreign matter such as dust is attached thereto, and in this state, the power is turned on. Then, the control unit 28 performs initialization processing and then sends a control signal to the motor 26 via the driver 27. As a result, the motor 26 is rotationally driven and the reference roller 1 starts rotating. Then, when the rotational speed of the reference roller 1 increases and reaches a steady state, the output of the position sensor 6 is sent via the detection circuit 24 to determine whether or not the banknote 4 is present between the reference roller 1 and the detection roller 2. A signal representing this is sent to the control section 28. When the control unit 28, which constantly monitors this signal, detects that the banknote 4 is not present,
The output of the angular displacement sensor 3 at that time is stored in two sections t8 corresponding to the reference roller rotation. The angular displacement sensor 3 outputs a displacement signal when the banknote 4 is not being fed, and this signal is amplified by a predetermined amount by the amplifier 21 and then sent to the A/D converter 22. The signal is converted into a digital signal and sent to the counter 23. The counter 23 generates binary data when the banknote 4 is not being conveyed by counting the received digital signals. The binary data from the angular displacement sensor 3 when the banknote 4 obtained on the counter 23 is not being conveyed in this way is sent to the control unit 2.
8, and then stored in two storage units as first reference data D1. The first U obtained in this way
The quasi-data D1 is shown in FIG. 4(a).

As shown in the figure, since the detection roller 2 is pressed against the reference roller with a predetermined pressure, the steady state is when the detection roller 2 is in contact with the reference roller at a predetermined angle, and the amount of displacement at this time is fl shall be.

On the other hand, data of a value higher by a certain value than the amount of displacement outputted by the normal reference roller 1 to which no dust or the like is attached is stored in the storage unit 29 as the second J! It is stored as ill data D2. 1] This second reference data D2 is
This is used as a first threshold when a foreign object such as garbage, which will be described later, is present.

Next, when the device is in operation and the banknotes 4 are not being transported, that is, when the position sensor 6 is not detecting the banknotes 4, the detection of foreign objects such as dust as described below is always performed. It will be done.

That is, as shown in FIG. 3, consider a case where, for example, there is dust attached to the banknote 4 that has been conveyed, and this is transferred to the reference roller 1 and becomes a foreign object.

When the control unit 28, which always receives the signal from the angular displacement sensor 3, detects that the banknote 4 is not present, it stores the output of the angular displacement sensor 3 at that time in the storage unit 29 for one rotation of the reference roller. do.

That is, the angular displacement sensor 3 outputs a liquid level signal in a state where the banknote 4 is not being conveyed, and this signal is transmitted to the amplifier 21.
After a predetermined amplification is performed in , the signal is converted into a digital signal by an A/D converter 22 and sent to a counter 23 . The counter 23 binarizes the signal from the angular displacement sensor 3 by counting the received digital signal, and stores it in the storage section 29 as detection data DK via the control section 28. The detection data DK obtained in this way reflects the amount of displacement of the detection roller 2 due to foreign matter, and
A signal as shown in Figure (b) is obtained in which the location corresponding to the foreign object changes greatly.

Next, the control section 28 calculates the difference between the detection data DK obtained as described above and the first speech data D1 detected previously and stored in the storage section 29. The data representing the difference obtained in this way is a signal (DK-DI) in which the foreign object portion is prominent, as shown in FIG. 4(C).

Next, the difference signal (DK-DI) and the second M stored in advance in the storage unit 29 as a threshold value are used.
H4 data D2 is compared, and if there is a portion where the detected data DK is larger than the second reference data D2, that portion (fourth
It is determined that there is a foreign object (-1) in the area shown in FIG.

In addition, during normal thickness detection, that is, when the banknote 4 is conveyed to increase its thickness, the detection roller 2 moves up and down according to the thickness, and the sensor 3 uses the angular displacement to detect the amount of displacement. Outputs a corresponding signal. After this signal is amplified to a predetermined value by an amplifier 21, it is converted to a digital number 1- by an A/D converter 22 and sent to a counter 23. The counter 23 obtains thickness data of the banknote 4 as binary data by counting the received digital signals. Counter 23 in this way? 11 Regarding the thickness of banknotes 4
The value data is sent to the control unit 28, and in the control unit 28,
The validity of the banknote 4 is checked, and the banknote 4 is judged to be true or pass/fail the test.

As explained above, basic data indicating the amount of displacement of the detection roller 2 with respect to the surface position of the base roller 1 of the device is created in advance, and if the device is in operation and the banknotes 4 are not being conveyed. During the time period, the amount of variation of the detection roller 2 with respect to the surface position of the reference roller 1 is detected, and if the variation exceeds a predetermined value (threshold value) when compared with the above reference data, it indicates that foreign matter has adhered to the reference roller 1. Therefore, there is no possibility of errors in thickness detection due to foreign objects, and accurate thickness detection can be performed at all times.

Further, the threshold value may be an arbitrary value stored in the storage section 29.
Since it is stored and used, it is easy to change and the optimum value for the device can be used.

Furthermore, in the present invention, the reference roller is attached to the reference roller. It has a removing means for removing the foreign matter that has adhered to it.

That is, a scraper 7 is arranged opposite to the reference roller 1, and this scraper 7 is driven by a solenoid 9 via a lever 8.

Therefore, the scraper 7 is at a position where it is in close contact with the reference roller 1 (
It is shown by the chain line in FIG. ) is configured to selectively move to a position away from the reference roller 1, and is normally retracted to the position shown by the solid line in Figure 1, and is moved to the position shown by the solid line in Figure 1 only when removing foreign matter. It is designed to be driven to the position shown by the chain line.

The solenoid 9 is controlled by the control section 20 via the driver 10, and when the control section 20 determines that there is a foreign object on the reference roller 1 when there is no sheet on the reference roller 1, the control section 20 activates the driver. The solenoid 9 is driven via the roller 10 to bring the scraper 7 into close contact with the reference roller 1 to remove foreign matter.

Since the scraper 7 removes foreign matter from the reference roller 1, the removed foreign matter may adhere to the scraper 7, especially the first roller 1.
In the figure, foreign matter tends to collect on the lower surface of the scraper 7 depending on the direction of rotation of the reference roller 1.

Therefore, the foreign matter collected on the scraper 7 is removed from the reference roller 1.
There is a risk of re-adhering to the Especially when paper sheets are placed on the reference roller 1.
If the paper is jammed between the paper sheet and the detection roller, the reference roller 1 may rotate in the opposite direction to the normal rotation direction when removing the paper sheet, and there is a risk that foreign matter may adhere to the reference roller 1 again. be.

However, the scraper 7 is normally retracted to the position shown by the solid line in FIG. 1, so that it does not come into contact with the reference roller 1.

Therefore, there is no fear that the foreign matter collected on the scraper 7 will adhere to the reference roller 1 again, and the thickness of the paper sheet can be detected reliably.

[Effects of the Invention] As described in detail above, according to the present invention, when it is detected that a foreign object has adhered to the reference roller, the foreign object is removed, so there is no false detection due to the foreign object, and the means for removing the foreign object can be used to remove the foreign object. Since it operates only when the reference roller is detected, it is effective in preventing foreign matter from adhering to the reference roller again.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the main parts of the paper sheet thickness detection device of the present invention, Fig. 2 is a block diagram of the electric circuit of the device shown in Fig. 1, and Fig. 3 shows the state with dust attached. FIG. 4 is a sectional view for explaining the operation, and a waveform diagram for explaining the operation. DESCRIPTION OF SYMBOLS 1... Reference roller, 2... Detection roller, 3... Angular displacement sensor, 4... Banknote (paper sheet), 6... Position sensor (paper sheet detection means), 7...・Scraper (removal means) 8... Lever 9... Solenoid, 1o...
・Driver, 24... Detection circuit, 28... Control department agent Patent attorney Noriyuki Chika Ken Yudo Yamashita Figure 1 Figure 2

Claims (1)

[Claims] A sheet of paper, which is an object to be measured, is fed between a reference roller that serves as a standard for thickness measurement and a variable detection roller that contacts this reference roller, and the variation of the detection roller at this time is In the thickness detection device that detects the thickness of paper sheets by converting the thickness into an electric signal, the paper sheet detection means detects that there is no paper sheet between the reference roller and the detection roller; , when this paper sheet detection means detects that there is no paper sheet between the reference roller and the detection roller, converts the amount of variation of the detection roller into an electric signal and compares the detection data with the reference data. a comparison means for determining that foreign matter is attached to the reference roller when the detected data exceeds a predetermined value with respect to the reference data as a result of comparison by the comparison means; A paper sheet thickness detecting device comprising a removing means for removing foreign matter from the reference roller when adhesion of foreign matter is detected as a result of the determination.