EP1764751B1

EP1764751B1 - Thickness detector for paper sheet and paper money handling device

Info

Publication number: EP1764751B1
Application number: EP05751338A
Authority: EP
Inventors: Takashi Yoshida; Akira Mori; Masanori Terao
Original assignee: Hitachi Omron Terminal Solutions Corp
Current assignee: Hitachi Omron Terminal Solutions Corp
Priority date: 2004-06-18
Filing date: 2005-06-17
Publication date: 2012-10-24
Anticipated expiration: 2025-06-17
Also published as: CN1820286A; TWI273516B; WO2005124702A1; KR20060030522A; JP4444738B2; CN1820286B; TW200620164A; EP1764751A4; EP1764751A1; JP2006004206A; KR100769374B1

Description

BACKGROUND OF THE INVENTION

(FIELD OF TECHNOLOGY)

The present invention relates to a sheet thickness detecting apparatus for detecting altered sheets.

(Background of Art)

In bill handling machines such as an automated teller machine, automatic vendor or the like, it is of important to identify bills altered by using a tape, the other paper or the like. A bill identification apparatus is provided for this purpose.
Especially in recent years, such alteration techniques have become increasingly sophisticated, and bills, securities, stamps and checks altered by using a tape, paper or label are in circulation on the market.
The previous apparatus for identifying altered bills with a tape, paper or the like is disclosed in Japanese utility model publication No. 6 (A.D. 1994)-49442 .
The previous apparatus has a sheet thickness detecting apparatus that is comprised of a reference roller to be driven; and a detecting roller whose outer ring is pressed toward the reference roller, wherein an elastic member is used for connection between the outer ring and its rotary shaft in such a way that the detecting roller becomes capable of rotating depending on the rotation of the reference roller. Sheets are fed between the reference roller and detecting roller so that the slight blunt prominence of the tape (hereinafter referred to as "slight prominence") is identified in response to the displacement of the outer ring.
[Patent Document 1] Japanese utility model publication No. 6 (A.D.1994)-49442
The document EP0080309 discloses an apparatus for detecting double feeding or overlapping of banknotes by means of having two rollers in-between which banknotes are conveyed into, one of the rollers being a follower roller that displaces vertically depending on the thickness of the banknote(s) fed. This displacement is sensed by two sensors located over each end of the follower roller, the sensors transforming said displacement into corresponding voltage, the said voltage being increased when the thickness of the banknote(s) inserted increases. The increase in the voltage from the sensors reveals the existence of a double feeding or an overlap of banknotes. The same method may be used to detect tape or any other adhesive element to the banknotes.

SUMMARY OF THE INVENTION

(PROBLEMS TO BE SOLVED BY THE INVENTION)

In the apparatus described in the aforementioned Patent Document 1, when the detecting roller insufficiently rides on the tape or the other paper adhered on the sheet when the sheet passes through the detecting roller, the detecting roller tilts toward the rotary shaft due to uneven shrinkage of the elastic member. Consequently, it may be possible not to accurately detect the slight prominence caused by the adhered tape or the adhered paper on the sheet.
The object of the present invention is to solve the aforementioned problem and to provide a sheet thickness detecting apparatus capable of accurately detecting the slight prominence even when the detecting roller insufficiently rides on the tape or the other paper adhered on the sheet when the sheet passes through the detecting roller.

(Means for Solving the Problems)

The aforementioned object of the present invention can be achieved by the following apparatus. The apparatus has reference rollers disposed on a drive shaft, and detecting rollers capable of rotating depending on the reference rollers by contacting with an outer ring of the reference rollers. The apparatus is configured to detect the thickness of a sheet by the amount of displacement of the detecting rollers at the time when the sheet is fed through between both rollers; and detection of the presence or absence of a slight blunt prominence on the sheet is performed with addition of the displacements of the detecting rollers.
The aforementioned object of the present invention can also be achieved by the following arrangement. The outer ring of each detecting roller is made of a cylindrical hard member, and an elastic member is interposed between the hard member and a rotary shaft of the detecting roller.
The aforementioned object of the present invention can also be achieved by the following arrangement. A plurality of detecting rollers are provided. Detection of the presence or absence of the slight blunt prominence on the sheet is performed with the displacement of each of said detecting rollers, and also performed with addition of the displacements of the detecting rollers adjacent to each other.
The aforementioned object of the present invention can also be achieved by the following apparatus. The apparatus also has reference rollers disposed on a drive shaft, and detecting rollers capable of rotating depending on the reference rollers by contacting with an outer ring of the reference rollers. The apparatus is configured to detect the thickness of a sheet by the amount of displacement of the detecting rollers at the time when the sheet is fed through between both rollers. The apparatus is further configured to obtain the height of a slight blunt prominence on the sheet by subtracting the previously stored thickness of the sheet from the displacement of each of the detecting rollers, and perform detection of the presence or absence of the slight blunt prominence with addition of the heights of slight blunt prominences obtained from the displacements of the adjacent detecting rollers.
The aforementioned object of the present invention can also be achieved by the following arrangement. The apparatus performs double detections of the presence or absence of the slight blunt prominence on the sheet. One detection of the presence or absence of the slight blunt prominence is performed based on the displacement of each of the detecting rollers. Another detection of the presence or absence of the slight blunt prominence is performed based on the addition of the heights of the slight blunt prominences obtained from the displacements of adjacent detecting rollers.
The aforementioned object of the present invention can also be achieved by the following apparatus. The apparatus has also reference rollers disposed on a drive shaft, and detecting rollers capable of rotating depending on the reference rollers by contacting with an outer ring of the reference rollers. The sheet thickness detecting apparatus is configured to detect the thickness of a sheet by the amount of displacement of the detecting rollers at the time when the sheet is fed through between both rollers. The apparatus is further configured to differentiate the amount of displacement obtained with addition of the position-by-position bill displacements of the adjacent detecting rollers, and detect the height of a slight blunt prominence on the sheet based on the differentiated value.
The aforementioned object of the present invention can also be achieved by the following arrangement. The detection of the presence or absence of the slight blunt prominence on the sheet is performed with the displacement of each of the detecting rollers. And furthermore the height of the slight blunt prominence on the sheet is detected based on the differentiated value.
The aforementioned object of the present invention can also be achieved by the following apparatus. The apparatus has also a reference roller provided on a drive shaft, and a detecting roller capable of rotating depending on the reference roller by contacting with an outer ring of the reference roller. The apparatus is configured to detect the thickness of a sheet by the amount of displacement of the detecting roller at the time when the sheet is fed through between both rollers. The apparatus is further configured to detect first and second displacements at both sides of the outer ring, obtain the heights of first and second slight blunt prominences on the sheet by subtracting the previously stored thickness of the sheet from the first and second displacements. And it detects the height of a slight blunt prominence on the sheet from the detecting roller inclination obtained by subtracting the heights of the first and second slight blunt prominences.
The aforementioned object of the present invention can also be achieved by the following arrangement. The apparatus is further configured to detect the sheet having the slight blunt prominence from the first and second displacements at the both sides of the outer ring. And furthermore it detects the height of a slight blunt prominence on said sheet from the detecting roller inclination obtained by subtracting the heights of the first and second slight blunt prominences, which are obtained by subtracting the previously stored thickness of the sheet from the first and second displacements.
The aforementioned object of the present invention can also be achieved by the following arrangement. The roller inclination is the value obtained by addition of the inclinations of the adjacent detecting rollers.
The aforementioned object of the present invention can also be achieved by the following apparatus. The apparatus has also a reference roller provided on a drive shaft, and a detecting roller capable of rotating depending on the reference roller by contacting with an outer ring of the reference roller. The apparatus is configured to detect the thickness of a sheet by the amount of displacement of the detecting roller at the time when the sheet is fed through between both rollers. The apparatus is further configured to detect the height of a slight blunt prominence on the sheet by detecting light projected in the direction of the rotary shaft of the detecting roller and by obtaining the displacement of the detecting roller based on the projected light.
The aforementioned object of the present invention can also be achieved by the apparatus. The apparatus has also a reference roller provided on a drive shaft, and a detecting roller capable of rotating depending on the reference roller by contacting with an outer ring of the reference roller. The apparatus is configured to detect the thickness of a sheet by the amount of displacement of the detecting roller at the time when the sheet is fed through between both rollers. The apparatus is further configured to make doubly sure of detection of the sheet having a slight blunt prominence, by detecting the sheet having a slight blunt prominence based on the detecting roller displacement, and also detecting the sheet having a slight blunt prominence based on detection of the inclination of the detecting roller in the direction of the rotary shaft.

(Effects of the Invention)

The present invention provides a bill handling machine, suitable for use as an automatic cash handling machine, capable of high-precision detection of overlapped sheet feeding in which bills more than or equal to two bills fed at one time, and altered bills with a tape or the other paper.

DETAILED DESCRIPTION OF THE INVENTION

(Best Mode for Carrying Out the Invention)

The following describes embodiments of the present invention with reference to drawings.

[Embodiment 1]

Fig. 1 shows an embodiment of the sheet thickness detecting apparatus of the present invention.
The thickness detector of Fig. 1 is comprised of the following components: a reference roller shaft 2 driven by a drive device (not illustrated); reference rollers 1a and 1b disposed on the reference roller shaft 2 as a drive shaft; and detecting rollers 5a and 5b disposed on a detecting roller shaft 6. The detecting rollers 5a and 5b are respectively pressed toward the reference rollers 1a and 1b to rotate with their shaft 6 depending on the rotation of the reference rollers 1a and 1b. Furthermore, the thickness detector has displacement sensors 9a and 9b such as eddy-current displacement sensors for detecting the movement of the detecting rollers that move upward in response to the thickness of the sheet.
The detecting rollers 5a and 5b has respectively outer rings 8 made of a cylindrical member such a metal. A soft elastic member 7 such as a rubber is filled between the outer ring 8 and detecting roller shaft 6. The elastic member 7 and outer ring 8 can be either bonded or non-bonded. Thus, when a bill 3 (sheet) becomes caught between the reference rollers 1a, 1b and detecting roller 5a, 5b, the elastic member 7 is deformed by the thickness of the sheet and the outer ring 8 moves upward. This displacement is detected by the displacement sensors 9a and 9b, and detection information 10a and 10b in response to the thickness of the bill 3 (sheet) are outputted. The detection information 10a and 10b are sent to the determination unit 11. The determination unit 11 checks the detection information 10a and 10b and the position information 13 as to the skew (skew in the bill conveying direction) and shift (shift in direction orthogonal to the bill conveying direction) when the bill has passed through the detecting roller. As the results of checking those information, the determination unit 11 determines whether overlapped bills more than or equal to two sheets has been fed, or whether the altered bill with tape has been fed. Then the determination information 12 is outputted.
Additionally, the position information 13 is used to correct the bill detection information that has detected the bill with a skew into the one free from the skew, and to find out the position where the bill 3 has passed through the detecting roller. It also indicates the existence of the tape 4 on the bill 3 when the tape 4 is adhered to the bill. In Fig 1, the bill 3 is fed in the direction vertical to the surface of the drawing sheet.
Fig. 1 is shows a state where the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 5a and 5b, and the respective elastic members don't shrink evenly; therefore, the detecting rollers 5a and 5b is tilting in the direction of rotary shaft. In this case, the output of the displacement sensors 9a and 9b is smaller than the value obtained by addition of the thickness of tape 4 to the thickness of the bill 3. In this case, the displacement output conforms to the distance between the detection center of the sensor and the outer ring.
Although the aforementioned description refers to the two sets of reference rollers and detecting rollers, in actuality a plurality of reference rollers and detecting rollers are arranged to detect the entire surface of the bill.
Referring to Figs. 2, 3 and 4, the following describes how to check the tape adhered to the bill in the determination unit 11:
Fig. 2 shows the changes in the displacement detection information 15 and 19 from the displacement sensors 9a and 9b when the altered bill with tape has passed through the detecting rollers 5a and 5b shown in Fig. 1.
In Fig. 2, the vertical axis indicates outputs of the displacement sensors. The horizontal axis denotes the distance of bill movement. Reference numerals 16 and 20 denote the displacement outputs corresponding to the bill section. Reference numerals 17 and 21 denote the displacement outputs corresponding to the tape section. The displacement addition information 23 is information obtained by addition of the displacement detection information 15 and 19. Similarly, reference numerals 24 and 25 indicate the addition outputs corresponding to the bill section and tape section by addition of the displacement detection information, and 18, 22 and 26 indicate the threshold value for determination processing.
Since the thickness of the bill differs according to position, these threshold values are selected from the data stored in advance in response to the position where the bill passes through the detecting roller. If the displacement detection information 15 and 19 and the displacement addition information 23 are equal to or greater than the threshold values, the determination unit determines that a tape is present. If they are less than the threshold values, the unit determines that a tape is not present.
Fig. 3 shows the tape thickness information 29 obtained by the following point-plotting technique. For every passage points where the right side of the tape 4 adhered to the bill 3 has passed through the any one detecting roller shown in Fig. 1, the thickness of the tape 4 is calculated by subtracting the thickness of the bill at the passage point from the detection information of the displacement sensor. The calculated tape thickness information is plotted for the every passage points.
In Fig. 3, numerals 36 and 37 denote the right and left sides of the reference roller 1a shown in Fig. 1. Similarly, 38 and 39 denote the right and left sides of the reference roller 1b. The tape thickness information 31 indicates the thickness of the tape 4 detected by the displacement sensor 9a. The tape thickness information 32 indicates the thickness of the tape 4 detected by the displacement sensor 9b. A numeral 33 indicates the state where the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4. In the state 33, the respective detecting rollers are tilted and smaller value than actual thickness has been detected as the thickness of the tape 4. The smaller value is outputted from each displacement sensors.
The tape thickness addition information 30 indicates the thickness of the tape obtained by addition of the tape thicknesses 31 and 32 obtained from the adjacent displacement sensors 9a and 9b.
Reference numeral 34 denotes the threshold value for determination processing. If the tape thickness information 31 and 33 and tape thickness addition information 30 are equal to or greater than the threshold value 34, then the processing determines that a tape is present. If not, the processing determines that a tape is not present.
Fig. 4 shows the waveform of the tape thickness information obtained by subtracting the bill thickness for every passage, from the displacement detection information of the respective displacement sensors.
In Fig. 4, tape thickness information 40 denotes the waveform obtained by subtracting the bill thickness for every passage position from the displacement detection information detected by the displacement sensor 9a. The tape thickness waveform 41 denotes the waveform obtained by subtracting the bill thickness for every passage position of from the displacement detection information detected by the displacement sensor 9b. Further, the tape thickness addition information 42 indicates the waveform obtained by addition of the tape thicknesses 40 and 41 obtained from the adjacent displacement sensors 9a and 9b.
Reference numerals 17, 21 and 24 indicate the waveform showing the thickness of the tape section. Numeral 34 shows the threshold value for determination processing. If the tape thickness information 40 and 41 and tape thickness addition information 42 indicate the values equal to or greater than the threshold value 34, the processing determines that a tape is present. If not, the processing determines that a tape is not present.
As described above, when the detecting rollers 5a and 5b shown in Fig. 1 has tilted, the output of the displacement sensor will decline. For the displacement detection information 15 and 19 obtained from the displacement sensors shown in Fig. 2, each of their values does not exceed the determination threshold values 18 and 19, so that the presence of a tape can be not detected by only each of displacement detection information 15 and 19.
Similarly, for the tape thickness information 31 and 32 shown in Fig. 3, each of their values does not exceed the determination threshold values 34, so that the presence of a tape can be not detected.
Similarly, for the tape thickness information 40 and 41 shown in Fig. 4, each of their values does not exceed the determination threshold values 34, so that the presence of a tape can be not detected.
However if using the displacement addition information 23 obtained by addition of the displacement detection information 15 and 19 obtained from the adjacent displacement sensors 9a and 9b shown in Fig. 2, the presence of a tape can be detected. Because the tape detection information at the tape section is enlarged with the addition, even when the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 5a and 5b, and even when the detecting rollers 5a and 5b has tilted. This advantage is provided by the present invention.
Similarly, if using the tape thickness addition information 30 obtained by addition of the tape thickness information 31 and 32 obtained from the displacement sensors 9a and 9b shown in Fig. 3, the presence of a tape can be detected. Because the tape detection information at the tape section is enlarged with the addition, even when the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 5a and 5b, and even when the detecting rollers 5a and 5b has tilted.
Similarly, if using the tape thickness addition information 42 obtained by addition of the tape thickness information 40 and 41 obtained from the displacement sensors 9a and 9b shown in Fig. 4, the presence of a tape can be detected. Because the tape detection information at the tape section is enlarged with the addition, even when the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 5a and 5b, and even when the detecting rollers 5a and 5b has tilted.

[Embodiment 2]

Fig. 5 shows another embodiment of the method of determining the tape adhered on the bill in the determination unit 11.
In Fig. 5, the tape thickness differentiation information 43 shows the information as a result of differentiating the tape thickness addition information 42 of Fig. 4. Reference numerals 44 and 45 indicate the threshold values for determination processing. If the absolute value of the tape thickness differentiation information 43 is equal to or greater than the threshold value 44 (absolute value of threshold value 44: the value is equal to threshold value 45), the processing determines that a tape is present. If not, the processing determines that a tape is present.
The same result is obtained by differentiating the displacement addition information 23 obtained by addition of the adjacent displacement detection information of Fig. 2.
According to this embodiment, by using the tape thickness differentiation information 43 based on the tape thickness addition information 42 of the tape thickness information 40 and 41 obtained from the displacement sensors 9a and 9b, the presence of a tape can be detected. Because the differentiation information at the tape section is enlarged with the addition, even when the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 5a and 5b, and even when the detecting rollers 5a and 5b has tilted.
Further, the present invention described above refers to the method where the presence of tape is detected from the following information: the information obtained by the addition of adjacent displacement thickness detection information; the information obtained by the addition of adjacent tape thickness information; and the information obtained by the differentiation of their addition information. An altered bill can also be detected by a combination of the two of the results of determination based on the displacement detection information detected for each detecting roller, the information obtained by the addition of adjacent displacement thickness detection information, the information obtained by the addition of adjacent tape thickness information, and the information obtained by the differentiation of the addition of adjacent tape thickness information.
The present invention described above refers to the application in the case where one displacement sensor is used for one detecting roller. However, a plurality of displacement sensors can also be used for one detecting roller, as shown in Fig. 6.

[Embodiment 3]

Fig. 6 shows a further embodiment of a sheet thickness detecting apparatus wherein two displacement sensors are used for one detecting roller.
The sheet thickness detecting apparatus of Fig. 6 has the same arrangement as that of Fig. 1, except that the displacement sensors 54a, 54b, 54c and 54d are used to detect the displacement on both sides of the outer ring 53 of the detecting rollers 50a and 50b, whereby the sheet thickness is detected.
That is, detecting rollers 50a and 50b is disposed on a detecting roller shaft 51. The detecting rollers 50a and 50b are respectively pressed toward the reference rollers 1a and 1b to rotate with their shaft 51 depending on the rotation of the reference rollers 1a and 1b. Furthermore, the thickness detector has displacement sensors 54a, 54b and 54c, 54d such as eddy-current displacement sensors for detecting the movement of the detecting rollers that move upward in response to the thickness of the sheet.
The detecting rollers 50a and 50b has respectively outer rings 53 made of a metallic or other cylindrical member. Soft elastic members 52a and 52b such as a rubber filled between both inner sides of each outer ring 53 and detecting roller shaft 51, in a separate form. The elastic members 52a and 52b and outer ring 53 can be either bonded or non-bonded. Thus, when a sheet becomes caught between the reference rollers 1a, 1b and detecting rollers 50a, 50b, the elastic members 52a and 52b are deformed by the thickness of the sheet and the outer ring 53 moves upward. This displacement is detected by the displacement sensors 54a, 54b, 54c and 54d, and detection information in response to the thickness of the sheet is outputted.
The detection information is sent to the determination unit 55. The determination unit 55 checks the detection information and the position information 57 as to the skew (skew in the bill conveying direction) and shift (shift in direction orthogonal to the bill conveying direction) when the bill has passed through the detecting roller. As the results of checking those information, the determination unit 11 determines whether overlapped bills more than or equal to two sheets has been fed, or whether the altered bill with tape has been fed. Then the determination information 56 is outputted. The position information 56 is used to correct the detection information that there is no skew, and to find out the position where the bill has passed through the detecting roller. It also indicates the existence of the tape 4 on the bill 3 when the tape 4 is adhered to the bill. In Fig 6, the bill 3 is fed in the direction vertical to the surface of the drawing sheet.
Fig. 6 shows a state where the respective detecting rollers 50a and 50b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 50a and 50b, and the respective elastic members don't shrink evenly; therefore, the detecting rollers 50a and 50b is tilting in the direction of rotary shaft. In this case, the output of the displacement sensors 9a and 9b is smaller than the value obtained by addition of the thickness of tape 4 to the thickness of the bill 3. In this case, the displacement output conforms to the distance between the detection center of the sensor and the outer ring.
Fig. 7 shows the tape thickness information obtained by the following point-plotting technique. For every passage points where the right side of the tape 4 adhered to the bill 3 has passed through the any one detecting roller shown in Fig. 6, the thickness of the tape 4 is calculated by subtracting the thickness of the bill at the passage point from the detection information of the displacement sensor. The calculated tape thickness information is plotted for the every passage points.
In Fig. 7, numerals 69 and 70 denote the right and left sides of the reference roller 1a. Similarly, 71 and 72 denote the right and left sides of the reference roller 1b. The tape thickness information 61 indicates the thickness of the tape 4 detected by the displacement sensor 54a. The tape thickness information 62 indicates the thickness of the tape 4 detected by the displacement sensor 54b. The tape thickness information 63 indicates the thickness of the tape 4 detected by the displacement sensor 54c. The tape thickness information 64 indicates the thickness of the tape 4 detected by the displacement sensor 54d. The numeral 59 indicates the threshold value for determination processing.
If the tape thickness information 61, 62, 63 and 64 becomes a value equal to or greater than the threshold value 59, the processing determines that a tape is present. If not, the processing determines that a tape is present.
A numeral 67 indicates the state where the respective detecting rollers 50a and 50b insufficiently ride on both sides of the tape 4. In the state 67, the respective detecting rollers are tilted and smaller value than actual thickness has been detected as the thickness of the tape 4. The smaller value is outputted from each displacement sensors.
The roller tilt information 60 indicates the tilt of the roller. The roller tilt information 65 indicates the absolute value calculated by subtracting the tape thickness information 61 from the tape thickness information 62. The information 61 and 62 is obtained from the adjacent displacement sensors 54a and 54b. In addition, the information 65 indicates the tilt of the roller 50a. Similarly, the roller tilt information 66 indicates the absolute value calculated by subtracting the tape thickness information 63 from the tape thickness information 64. The information 62 and 64 is obtained from the adjacent displacement sensors 54c and 54d. In addition, the information 66 indicates the tilt of the roller 50b. Numeral 68 denotes the threshold value for the determination processing. If the roller tilt information 65 and 67 become the values equal to or greater than the threshold value 68, the processing determines that a tape is present. If not, the processing determines that a tape is not present.
The roller tilt addition information 73 indicates the value obtained by addition of the adjacent roller tilt information 65 and 66. The numeral 74 indicates the threshold value for determination processing. If the roller tilt addition information 73 becomes a value equal to or greater than the threshold value 74, the processing determines that a tape is present, because the roller exhibits a greater tilt. If not, the processing determines that a tape is not present.
According to the present invention, by using the tape thickness information 61, 62, 63 and 64, and the roller tilt information 65 and 67, the presence of a tape can be detected, even when the respective detecting rollers 5a and 5b insufficiently ride on both sides of the tape 4 when the sheet passes through the rollers 5a and 5b, and even when the detecting rollers 5a and 5b has tilted.
The presence of a tape can be detected by using a combination of the results of determination based on the tape thickness information 61, 62, 63 and 64 and roller tilt addition information 73, even if the tape 4 has passed through any position of the detecting roller.

[EMBODIMENT 4]

Fig. 8 shows a still further embodiment of a sheet thickness detecting apparatus.
The sheet thickness detecting apparatus of Fig. 8 has the same arrangement as that of Fig. 1, except that the optical sensors are used as the displacement sensors for detecting the displacement of the detecting rollers 5a and 5b.
The displacement sensor is comprised of a light-emitting device 76, a photo-receiver 78, a light-emitting device 79 and a photo-receiver 81. They are arranged opposite to each other in such a way that the upper portions of the detecting rollers 5a and 5b will cut off a part of the strip rays 77 and 80. The strip rays from the light-emitting device are detected by the photo-receiver. The displacement is detected according to the amount of light received or the light receiving position of the linearly arranged light receiving element. Thus, in the present invention, the displacement of each detecting roller is detected by detection of the projection light of the detecting roller, whereby the thickness of the sheet is detected.
The maximum displacement of a plurality of detecting rollers can be detected by arranging a pair of light light-emitting device and photo-receiver face to face with each other, wherein these rollers are placed in-between.
As described above, the projected light of the detecting roller is detected, and this avoids deterioration of detection output even when the detecting roller is tilted. Thus, the present invention ensures high-precision tape detection.

[EMBODIMENT 5]

Fig. 9 shows a still further embodiment of the sheet thickness detecting apparatus.
The sheet thickness detecting apparatus of Fig. 9 has the same arrangement as that in Fig. 1, except that electrostatic capacitance type displacement sensors 85 and 86 for detecting the tilt of the detecting rollers 5a and 5b in the direction of the rotary shaft.
The electrostatic capacitance type displacement sensors 85 and 86 are used to detect the electrostatic capacitance between the electrodes 88 and 87. When the detecting roller has tilted, a change occurs in the distance between the detecting roller and electrode. This is detected as a change in the electrostatic capacitance.
In the present invention, ever when the detecting rollers insufficiently ride on both sides of the tape and tilt, such states of the detecting rollers can be detected. Accordingly, this arrangement permits high-precision detection of the presence of a tape.
Fig. 10 shows an example of the embodiment of an automated teller machine having the sheet thickness detecting apparatus of the present invention.
In Fig. 10, a bill handling machine 90 in the automated teller machine is comprised of:

a bill reception/payment section 91, which separates deposited bills 96a into denomination for storing them at the time of cash being deposited, and pays the amount specified by a user at the time of cash payment;
a bill conveying paths 92a and 92b;
an image sensor for detecting the design of the bills;
a magnetic sensor for detecting the magnetic pattern of the bills;
a bill identification apparatus, which is composed of a fluorescent sensor for detecting the fluorescence formed on each of the bill to identify the denomination of the bills and make an authentication of the bills;
a bill validation apparatus 97, which makes a an authentication of each of the bills by using the sheet thickness detecting apparatus of the present invention. The sheet thickness detecting apparatus is capable of detecting whether overlapped sheets more than or equal to two sheets has been fed or whether the bill has been altered by using a tape or the other paper, thereby authenticates the bill. The bill handling machine 90 is further comprised of: a temporary stacker 93 for stacking bills on the temporary basis at the time of storing or paying bills; a bill collection case 94 for storing the bills that cannot be handled by the machine; and a denomination storage case 95a, 95b and 95c for storing and paying the bills 96b for each denomination.

The following describes the operation of the aforementioned automated teller machine.
At the time of depositing the bills 96a, the bills put into the bill deposit/payment mechanism 91 are separated into one by one, and are fed to the conveying path 92a. The bill validation apparatus 97 determines if each bill is altered or not. It also determines if one bill or more than one bills is fed at one time. When determining that the bill is not altered and one bill is fed at one time or the bill is folded one, it is placed in the temporary stacker 93 and the amount of transaction is displayed. If the bill(s) having been put into the machine has any problem, all of them are returned to the bill deposit/payment mechanism 91.
When the transaction has been concluded, the bills are fed to the bill validation apparatus 97 again, wherein a check is made to see if one or more than one bill is fed at one time. Then the bills are stored into the storage case for each denomination.
On the other hand, at the time of cash repayment, bills 96b stored in the denomination storage case 95 are fed to the conveying path 92b by the specified amount while being separated into one by one. In this conveying process, the bill validation apparatus 97 checks if one bill or more than one bill is fed at one time. When the bills are separated into one by one, they are fed to the bill reception/payment section 91 one by one. If overlapped bills more than one bill or folded bill(s) are detected, the detected bill is placed in the temporary stacker, and is then put into the bill collection case 94. The bill validation apparatus 97 is designed to perform its function in either of forward and reverse bill-conveying directions.
According to the present invention, by using the bill validation apparatus with the sheet thickness detecting apparatus of the present invention, it makes possible to detect with high-precision the overlapped sheet-feeding where bills more than one sheet are fed, or altered bills with tape, other paper or the like.
The aforementioned description refers mainly to the case where an eddy current type displacement sensor is used as a displacement sensor. It is also possible to use an electrostatic capacitance type displacement sensor, optical displacement sensor or contact type displacement sensor. The aforementioned description also refers to the sheet thickness detecting apparatus used in the automated teller machine. It also can be used as a sheet thickness detecting apparatus of an automatic vendor.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows an embodiment of the sheet thickness detecting apparatus of the present invention;
Fig. 2 shows the displacement detection information of Fig. 1 in the present invention, the displacement addition information obtained by addition of adjacent displacement thickness detection information, and the threshold value for tape identification;
Fig. 3 shows the tape thickness detection information of Fig. 1 in the present invention, the tape thickness addition information obtained by addition of adjacent tape thickness detection information, and the threshold value for tape identification;
Fig. 4 shows the tape thickness detection information of Fig. 1 in the present invention, the tape thickness detection information obtained by the addition of the adjacent tape thickness detection information, and the threshold value for tape identification;
Fig. 5 shows the differentiation information of the tape thickness detection information gained by the addition of the adjacent tape thickness detection information of Fig. 1 in the present invention;
Fig. 6 shows another embodiment of the sheet thickness detecting apparatus wherein two displacement sensors are provided on one detecting roller;
Fig. 7 shows the tape thickness detection information of Fig. 6 in the present invention, the roller inclination information obtained by subtracting the adjacent tape thickness detection information , the roller inclination information obtained by adjacent roller inclination information, and the threshold value for tape identification;
Fig. 8 shows a further embodiment of a sheet thickness detecting apparatus provided with the optical displacement sensor for detecting the projected light of the detecting roller in the present invention;
Fig. 9 shows a still further embodiment of the sheet thickness detecting apparatus provided with the inclination sensor for detecting the inclination of the detecting roller in the present invention; and
Fig. 10 shows an embodiment of the automatic cash handling apparatus in the sheet thickness detecting apparatus of the present invention.

[Legend]

1a, 1b:Reference roller, 2: Reference roller shaft, 3: Bills, 4: Tape, 5a, 5b: Detecting roller, 6: Detecting roller shaft, 7: Elastic member, 8: Outer ring, 9a, 9b: Displacement sensor, 10a, 10b: detection information, 11: Determination unit, 12: Determination information, 13: Position information as to skew.

Claims

A sheet thickness detecting apparatus comprising:
a plurality of reference rollers (1a, 1b) disposed on a drive shaft (2),

a plurality of detection rollers (5a, 5b; 50a, 50b) disposed on a detection roller shaft (6) and capable of rotating depending on said reference rollers while feeding a sheet (3) through between respective outer rings (8, 53) of said reference rollers and of said detection rollers, and

a plurality of displacement sensors (9a, 9b; 54a-54d) adapted to detecting displacements of said detection rollers in response to a thickness of a sheet and generating corresponding displacement information,

said sheet thickness detecting apparatus comprising means for detecting the presence or absence of a slight blunt prominence on the sheet using the displacement information of said displacement sensors at the time when said sheet is fed through between said both rollers by comparing a sum of the displacement detection information of two adjacent detection rollers with a predetermined threshold value.
The apparatus
described in Claim 1, wherein the outer ring (53) of each detection roller is made of a cylindrical hard member, and an elastic member (52a, 52b) is interposed between said hard member and a rotary shaft (51) of said detection rollers (50a, 50b).
The apparatus
described in Claim 1, wherein a plurality of said detection rollers are provided, detection of presence or absence of said slight blunt prominence on said sheet is performed based on a comparison of the displacement information of each of said detection rollers with a predetermined threshold value, and also based on a comparison of the sum of the displacement detection information of said two adjacent detection rollers with another predetermined threshold value.
A sheet thickness detecting apparatus comprising:
a plurality of reference rollers (1a, 1b) disposed on a drive shaft (2),

a plurality of detection rollers(5a, 5b; 50a, 50b) disposed on a detection roller shaft (6) and capable of rotating depending on said reference rollers while feeding a sheet (3) through between respective outer rings (8, 53) of said reference rollers and of said detection rollers, and

a plurality of displacement sensors (9a, 9b; 54a-54b) adapted to detecting displacements of said detection rollers in response to a thickness of a sheet and generating corresponding displacement information, wherein

said sheet thickness detecting apparatus comprises means for determining the presence or absence of a slight blunt prominence on said sheet using the displacement information of said displacement sensors at the time when said sheet is fed through between said both rollers; wherein

said determining means is further configured to obtain the height of a slight blunt prominence on said sheet by subtracting the previously stored thickness of said sheet from the displacement detection information of each of said detection rollers, and performing detection of presence or absence of a slight blunt prominence by comparing a sum or a differential value of the sum of heights of possible slight blunt prominences, which are obtained by subtracting the thickness of said sheet from the displacement detection information of two adjacent detection rollers, with a predetermined threshold value.
The apparatus described in Claim 4, wherein said determining means is configured to perform double detections of presence or absence of said slight blunt prominence on said sheet, by performing a first detection of presence or absence of said slight blunt prominence based on a comparison of the displacement detection information of each of said detection rollers with a first predetermined threshold value, and by performing a second detection of presence or absence of said slight blunt prominence based on a comparison of said sum of the heights of said possible slight blunt prominences obtained from the displacement detection information of said two adjacent detection rollers with a second predetermined threshold value.
A sheet thickness detecting apparatus comprising:
a plurality of reference rollers (1a, 1b) disposed on a drive shaft (2),

a plurality of detection rollers (5a, 5b; 50a,50b) disposed on a detection roller shaft (6) and capable of rotating depending on said reference rollers while feeding a sheet (3) through between respective outer rings (8, 53) of said reference rollers and of said detection rollers, and

a plurality of displacement sensors (9a, 9b; 54a-54b) adapted to detecting displacements of said detection rollers in response to thickness of a sheet and generating corresponding displacement information, wherein

said sheet thickness detecting apparatus comprises means for detecting the presence or absence of a slight blunt prominence on said sheet using the displacement information of said displacement sensors at the time when said sheet is fed through between said rollers; and

said sheet thickness detecting apparatus comprising means for differentiating a displacement value which is obtained from a sum of the displacement detection information of two adjacent detection rollers, and detect the presence or absence of a slight blunt prominence on said sheet based on said differentiated displacement value.
The apparatus described in Claim 6, wherein the apparatus is configure to further perform detection of presence or absence of said slight blunt prominence on said sheet based on a comparison of the displacement detection information of each of said detection rollers with a corresponding predetermined threshold value.
A sheet thickness detecting apparatus comprising:
a plurality of reference roller (1a, 1b) provided on a drive shaft (2),

a plurality of detection roller (50a, 50b) disposed on a detection roller shaft (6) and capable of rotating depending on said reference roller while feeding a sheet (3) through between respective outer rings (8,53) of said reference roller and of said detection rollers, and

a plurality of displacement sensors (9a-9b, 54a-54b) adapted to detecting displacements of said detection rollers in response to a thickness of a sheet and generating corresponding displacement information, wherein

said sheet thickness detecting apparatus comprises means for detecting the presence or absence of a slight blunt prominence on the sheet using the displacement information of said displacement sensors at the time when said sheet is fed through between said rollers; and

said sheet thickness detecting apparatus comprises first and second displacement sensors for each of the detection rollers for detecting first and second displacements for each of the detection rollers for detecting at both sides of said outer ring and generating a first and a second displacement information,

wherein said detection means comprises means for obtaining heights of a first and a second possible slight blunt prominences on said sheet by subtracting a previously stored thickness of said sheet from each of said first and second displacements respectively, and determining presence or absence of a slight blunt prominence on said sheet based on a detection roller inclination information obtained by subtracting the heights of said first and second possible slight blunt prominences from each other.
The apparatus described in Claim 8, wherein said apparatus is further configured to detect presence or absence of a slight blunt prominence on said sheet based on comparisons of said first and second displacements at the both sides of said outer ring with a predetermined threshold value.
The apparatus described in Claim 8 or 9,
wherein said roller inclination information is the value obtained by adding the inclination values of two adjacent detection rollers together.
The apparatus of one of the preceding claims
wherein the sheet is a bill with a tape.
A bill handling machine comprising a sheet thickness detecting apparatus described in any one of Claims 1 to 11.