JPH056490Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) This invention relates to a thickness detection device for paper sheets in a device that handles paper sheets such as banknotes.

(Technical background of the invention and its problems) Conventionally, when detecting paper sheets with abnormal thickness, such as two overlapping sheets or sheets with tape attached, etc. In general, displacement of a conveying roller or the like from a reference position is detected by optical or magnetic means. The distance between the rollers of such a detection device is adjusted in advance so that it will not displace even if only one sheet of paper is conveyed, but it is not easy to adjust the distance between the rollers and the distance between the rollers is constantly Without adjustment, it was not possible to accurately detect thickness abnormalities.

For this reason, an apparatus has been developed which keeps a pair of rollers in close contact with each other at all times and detects the thickness by detecting the displacement of one of the rollers when paper sheets are conveyed. However, even in such a detection device, the roller is in close contact with the paper sheet, so once dust from the paper sheet or sticky substance such as tape adheres to the roller surface, the rotation of the roller will be affected. This resulted in a strong pressure bond, which made it impossible to remove, and it was necessary to clean the roller surface as appropriate.

(Purpose of the invention) This invention was made in view of the above-mentioned circumstances, and the purpose of this invention is to remove paper dust and other objects attached to the rollers by rotating a pair of rollers at different circumferential speeds. It is an object of the present invention to provide a paper sheet thickness detection device which automatically removes deposits such as paper sheet thickness and which is easy to maintain.

(Summary of the invention) This invention relates to a paper sheet thickness detection device, which includes a conveying means that continuously conveys paper sheets one by one, and a pair of detection rollers depending on the paper sheets being conveyed. a detection roller means for displacing one of the detection rollers away from the other detection roller; a thickness determination means for determining the thickness of the paper sheet by detecting the amount of displacement of the detection roller; and a periphery of the pair of detection rollers. and drive means for rotating at different speeds. Then, the circumferential speed of one of the pair of detection rollers is the same as the conveyance speed of the conveyance means, and the circumferential speed of the other detection roller is faster than the circumferential speed of the one detection roller, respectively. Preferably.

(Example of the invention) Fig. 1 shows the schematic structure of the paper sheet thickness detection device of this invention, and the paper sheet thickness detection device is used to determine the thickness and denomination of paper sheets such as banknotes being conveyed. People are starting to do this. The paper sheet thickness detection device is provided with a first conveyance device 50 and a second conveyance device 60 separately. Paper sheets 100 from a storage section (not shown) are each held between a pair of upper and lower conveyor belt mechanisms and are continuously conveyed one by one in direction A at a speed of _V2 . A pair of upper and lower detection rollers 20A, 20 are provided between the first conveyance device 50 and the second conveyance device 60.
B is provided, and these detection rollers 20A and 20
B is connected to a roller drive device and a sheet thickness determining device, _which will be described later _. The thickness of the paper sheets 100 being rotated and conveyed by the thickness determining device is determined. Here, the conveying speed of the first conveying device 50 and the second conveying device 60 is the same speed (for example, the speed
V ₂ =2000mm/s), and the detection roller 20
The rollers A are rotated so that the circumferential speed is the same,
The circumferential speed of the detection roller 20B is higher than that of the detection roller 20A (for example, the speed V ₁ =2020 mm/
s). Here, the reason why the circumferential speeds of the pair of rollers 20A and 20B are different is that even if dust, tape, etc. attached to the paper sheet 100 being conveyed adheres to the detection rollers 20A and 20B, the difference in the rotational circumferential speeds of the rollers 20A and 20B. This is because the adhesion is automatically peeled off and removed by rubbing. Second conveyance device 6
A conventionally known denomination discriminating device 70 is provided in the middle of the paper sheet 100 to discriminate the denomination of the paper sheets 100 to be conveyed, and the denomination-discriminated paper sheets are conveyed to a paper sheet storage section or the like. Ru.

Figure 2 A and B are detection rollers 20A and 20B.
The structure and thickness discriminating device are shown in detail, with Figure A showing the front and Figure B showing the side. The thickness determination device is provided with a bearing 13 fitted to the side wall 14. One end of the shaft of the detection roller 20A is inserted into this bearing 13, and a shaft for rotational driving is provided on the outside of the side wall 14 of the shaft. A pulley 10 is inserted into the shaft, and a locking ring 12 is inserted into the tip of the shaft to prevent the shaft from falling out. Although not shown, a bearing and a locking ring similar to those described above are also provided on the other side of the shaft of the detection roller 20A.

On the other hand, the detection roller 20B is configured as a pair with the detection roller 20A, and a bearing 8 is inserted into one end of the shaft of the detection roller 20B outside the side wall 14, and a pulley 9 is further inserted into the outside of the bearing 8. At the same time, a locking ring 11 is provided at the tip. The bearing 8 is placed in a concave portion of the roller holder 7 that has a semicircular opening, and the upper detection roller 20B is pushed upward by the thickness of the paper sheet 100 that has been conveyed, and accordingly The bearing 8 is also pushed upward and floats out of the recessed portion of the roller holder 7. The other end of the shaft of the detection roller 20B is also provided with a bearing and a stop ring similar to those described above, and the bearing is placed on the recess of the roller holder. A detection arm 3 is provided on a side wall 14 above the bearing 8 so as to be rotatable about a shaft 6, and a bent lower end 31 of the detection arm 3 is attached to the bearing 8.
is engaged with the upper peripheral surface of. Axis 6 of detection arm 3
A protruding member 4A is vertically installed on the upper part of the side wall 1.
The lower end 31 of the detection arm 3 is always brought into contact with the upper circumferential surface of the bearing 8 with an appropriate pressure by the spring member 5 suspended between the spring member 5 and the protrusion member 4B provided on the detection arm 4. For this reason, bearing 8
The detection roller 20B coupled to the detection roller 20A is also in contact with the detection roller 20A with appropriate pressure. Further, a potentiometer 1 is provided on the side wall 14 above the detection roller 20B, a potentiometer arm 2 is attached to the rotation shaft 1A of the potentiometer 1, and a pressing portion 32 at the upper end of the detection arm 3 is attached to the rotation shaft 1A of the potentiometer 1. They are provided so as to engage with each other. And the lower end 3 of the detection arm 3
1 rises due to the movement of the bearing 8 based on the thickness of the paper sheet 100, the pressing part 32 pushes the upper end of the potentiometer arm 2 to the left in the figure, and the rotation shaft 1A of the potentiometer 1 is rotated. It's becoming like that. Note that drive belts (not shown) are suspended on the pulleys 9 and 10, respectively, and are rotated by a drive device (not shown) at the circumferential speeds V ₁ and V ₂ as described above.

FIG. 3 shows the details of the detection rollers 20A and 20B, and shows a paper sheet 100 being conveyed between the detection rollers 20A and 20B. A plurality of detection rollers 20A and 20B are provided in pairs, so that the detection rollers 20A and 20B can handle paper sheets of various widths.

Figures 4A and 4B show the operating principle of the paper sheet thickness discrimination device, where Figure A shows the standby state when no paper sheets are passing through, and Figure B shows the operating principle when paper sheets 100 are passing through. are shown respectively. In this thickness determination device, the detection arm 3 operates on the lever principle with the shaft 6 as the fulcrum, the lower detection roller 20A is fixed in position, and the upper detection roller 20B is connected to the spring member 5. It is constantly pressed downward via the detection arm 3. Here, as shown in FIG. 4B, when the paper sheet 100 is conveyed and passes between the detection rollers 20A and 20B, the paper sheet 100
The detection roller 20B is pushed upward by the thickness δ. Therefore, the lower end 31 of the detection arm 3 is also pushed up by the thickness δ via the bearing 8 coupled to the shaft of the detection roller 20B, and this displacement (thickness δ) causes the detection arm 3 with the shaft 6 as the fulcrum to be pushed up. is magnified (for example, 5 times) by the lever principle and presses the potentiometer arm 2 via the upper end pressing part 32, so the potentiometer arm 2 is rotated by the displacement angle θ, and the rotation of the potentiometer 1 is The shaft 1A also rotates by the same displacement angle θ.

Here, FIG. 5 shows an example of the output characteristics of the potentiometer 1, where the horizontal axis shows the displacement angle θ of the potentiometer, and the vertical axis shows the output voltage V of the potentiometer 1.

In Fig. 4B, the potentiometer arm 2 moves the rotation axis 1A of the potentiometer 1 from the reference angle θ ₀ (the output voltage of the potentiometer 1 at this position is V ₀ ), which is the standby position in Fig. 4A. When the displacement angle θ=x ₁ (e.g., equivalent to one sheet of paper) changes, the output V of potentiometer 1 also changes from V ₀ to V ₁ , and the displacement angle θ=x ₂ (e.g., equivalent to two sheets of paper). (equivalent), the output V of potentiometer 1 also changes to _V2 . Therefore, by determining the change in the displacement angle θ of the potentiometer 1 as a change in the voltage V, the thickness of the paper sheet can be determined. Next, the operation of the sheet thickness detection device will be explained with reference to FIGS. 1 to 5.

As shown in FIG. 1, first, when a paper sheet 100 is conveyed, it is automatically taken into the detection device by the first conveyance device 50, and the detection roller 20A and 2
When passing between 0B, the detection roller 20B is pushed upward according to the thickness δ of the paper sheet 100, as shown in FIGS. 3 and 4 A and B, and the displacement is applied to the bearing 8 and the detection arm. 3. The rotation shaft 1A of the potentiometer 1 is rotated via the potentiometer arm 2, and a voltage V is output with the characteristics shown in FIG. Detected. Paper sheets whose thickness was detected 1
00 is further conveyed to the conveyance device 60 by detection rollers 20A and 20B. Here, the detection rollers 20A and 20B are driven by a drive device (not shown).
Since they are rotated at mutually different peripheral speeds V ₂ and V ₁ via the pulleys 10 and 9, even if dust, tape, etc. from the paper sheet 100 adheres to the detection rollers 20A and 20B, the difference in peripheral speed will be ignored. Since the surface of the detection roller is constantly cleaned, highly accurate thickness detection can be performed. Furthermore, because the circumferential speed of one of the pair of detection rollers is set to be the same as the conveyance speed of the conveying means, and the circumferential speed of the other detection roller is set higher than that of the other detection roller, the Because of the small speed difference, there is no possibility of paper sheets getting jammed at the pair of detection rollers.

(Modified example of the invention) In the above-described embodiment, the outer diameter size of the pair of detection rollers for detecting the thickness of paper sheets is the same, and the circumferential speed of each detection roller is made different by making the rotation speed different. However, the outer diameter sizes of the pair of detection rollers may be different, and the circumferential speeds of the detection rollers may be made to differ by rotating each detection roller at the same rotational speed. Also,
In the above description, the thickness of the paper sheet is detected by the change in rotation angle of the potentiometer, but it is also possible to detect the thickness by pressure, displacement, or the like.

(Effects of the invention) According to the paper sheet thickness detection device of this invention, since the pair of detection rollers are always rotating at different circumferential speeds, dirt on paper sheets, tape, etc. Even if it sticks to the surface, it is automatically removed, so there is no need to constantly clean the detection roller surface, and maintenance is easy. Furthermore, since the displacement amount of one of the detection rollers is detected, even if the detection roller is worn out, it can be detected reliably, the thickness detection ability is improved, and reliability is high. Furthermore, it is possible to easily detect the thickness of various paper sheets by simply changing the set value of the thickness detection standard.

[Brief explanation of drawings]

Figure 1 is a schematic structural diagram of a paper sheet thickness detection device that is an embodiment of this invention, and Figures 2A and B show details of the thickness determination device, with Figure A being a front view and Figure B
is a side view of the same, FIG. 3 is a diagram showing the details of the detection roller, FIGS. 4A and B are diagrams for explaining the operating principle of the sheet thickness detection device, and FIG. 5 is the output characteristics of the potentiometer. It is a figure which shows an example. DESCRIPTION OF SYMBOLS 1... Potentiometer, 2... Potentiometer arm, 3... Detection arm, 4A, 4B... Projection member, 5... Spring member, 6... Shaft, 7... Roller holder, 8... Bearing, 9,10...Pulley,
11, 12...Axle stop ring, 13...Bearing, 20A, 20B...Detection roller, 50,60
...Conveyance device, 70...Denomination discrimination device, 100...
...paper leaves.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) Conveying means that continuously conveys paper sheets one by one, and a pair of detection rollers depending on the paper sheets being conveyed, one of which detects the other. a sensing roller means that is displaced away from the sensing roller; a thickness determining means that determines the thickness of the sheet by detecting the amount of displacement of the sensing roller; and a circumferential speed of the pair of sensing rollers, respectively. A paper sheet thickness detection device characterized by comprising: drive means that rotates in different directions. (2) The circumferential speed of one of the pair of detection rollers is the same as the conveyance speed of the conveying means, and the circumferential speed of the other detection roller is higher than the circumferential speed of the one detection roller, respectively. A rotating paper sheet thickness detecting device according to claim 1.