JP2928096B2 - Paper sheet upside down device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper sheet reversing apparatus mounted on a paper money handling apparatus or the like and having the front and back of paper sheets such as bills and slips.

[0002]

2. Description of the Related Art Conventionally, a sheet reversing device mounted on a banknote handling device or the like includes a front-facing sheet on a non-reversing conveyance path as disclosed in, for example, JP-A-63-12561. In some cases, the sheet is conveyed as it is, and the sheet that is turned backward is turned upside down and conveyed in the reversing conveyance path. In the sheet reversing device, the size of the device is reduced, and the influence of the sheet transported on the reverse transport path and the sheet transported on the non-reverse transport path in the stacking unit is affected. In order not to affect
When a sheet to be reversed and a sheet to be non-reversed are continuous, at the junction of the non-reversed conveyance path and the reversal conveyance path, the preceding reversing sheet and the subsequent non-reversing sheet continuing therefrom overlap. , the time the paper sheet is the passing time T ₁ the reverse conveying path, the time T ₂ required to pass through the non-inverting conveyance path, the delay time of the subsequent paper sheet with respect to the preceding paper sheet, i.e., the plus a paper pitch T ₃ The reverse transport path length and the non-reverse transport path length are set so that T ₁ = T ₂ + T ₃ .

[0003]

Here, in the above-mentioned sheet reversing apparatus, a plurality of sheets stored in the storage section are separated and fed one by one. It has become. When the sheets are separated one by one as described above, the separation interval varies depending on the state of the sheet, thereby causing the interval between the preceding sheet and the succeeding sheet to vary.

[0004] The above-mentioned conventional paper sheet reversing device.
Before branching to the reverse transport path or non-reverse transport path
Paper pitch T_ThreeThere is variation in this paper pitch T
_ThreeIs the transit time T for the length of the sheet in the transport direction from the set value
_FourOnly long T_Three'= T_Three+ T _FourIf it is above, it will precede
The reversal sheet and the subsequent non-reversal sheet following it are joined at the junction.
It will not overlap. Therefore, at the junction,
The inverted sheet of the line and the subsequent non-inverted sheet
And non-overlapping.

At two points on the paper transport path, the number of paper sheets that have passed is counted, and the two papers are compared. Is conveyed, and if there is a difference between the two, it can be determined that a conveyance abnormality such as a jam has occurred between the two points. By managing the number of paper sheets on the conveyance path, , It is possible to detect the transport state of the sheet.

However, as in the above-described conventional sheet reversing apparatus, when a reversing sheet precedes and is followed by a non-reversing sheet, the reversing sheet and the non-reversing sheet converge at the junction. If there is a case where the sheets overlap and a case where they do not overlap, it becomes impossible to accurately count the number of sheets after the confluence point, and it becomes impossible to manage the number of sheets after the confluence point. There is a problem that it cannot be detected.

The present invention has been made to solve such a problem, and provides a sheet reversing apparatus capable of controlling the number of sheets after the reversing conveyance path and the non-reversing conveyance path merge. The purpose is to do.

[0008]

In order to achieve this object, the present invention provides a discriminating section for discriminating the front and back of a sheet, and a sheet which has been discriminated to be turned upside down by the discriminating section without being turned upside down. A non-reversing conveyance path, a reversing conveyance path for reversing and conveying a sheet determined to be face-down, and a non-reversing conveyance path or a reversing conveyance path based on the discrimination result of the discriminating unit. A non-reversing transport path and a reversing transport path, wherein the non-reversing transport path and a reversing transport path for combining and transporting the sheets passing through the non-reversing transport path and the reversing transport path; A sensor for detecting whether or not the sheets conveyed through the merged conveyance path are overlapped on the merged conveyance path near the confluence point with, and from the output of the sensor, whether the sheets are overlapped. By determining whether or not the paper There are those that determine whether it has passed the place of the sensor by many pieces, provided with a control unit for counting the number of paper sheets to be conveyed confluence transportation path.

[0009]

According to the present invention having the above-described structure, a sheet determined to be upside down by the discriminating section is transported as it is through the non-reversing path, and a sheet determined to be upside down is transported by being turned upside down in the reverse path. Is done. Then, the sheets conveyed on the reversing conveyance path and the non-reversing conveyance path are merged and conveyed on the merging conveyance path.
At this time, by judging whether or not the sheets are conveyed in the merged conveyance path, it is determined how many sheets are conveyed, and it is determined that the sheets are conveyed by one sheet. Then, this is counted as one sheet, and when it is determined that two sheets are conveyed in an overlapped manner, this is counted as two sheets, and the number of sheets conveyed in the combined conveyance path is counted.

[0010]

An embodiment will be described below with reference to the drawings. FIG. 1 is a side view illustrating a configuration of a sheet reversing device according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a sheet reversing device, and the sheet reversing device 1 has the following configuration.

Reference numeral 2 denotes a discriminating section. The discriminating section 2 has transport belts 2a and 2b and a discriminator 2c. The transport belt 2a is endless and is hung on pulleys 2d and 2e. Also,
The transport belt 2b is endless and is hung on pulleys 2f and 2g so as to face the transport belt 2a. The discriminator 2c is disposed in the middle of the conveyance path of the paper sheet 21 by the conveyance belts 2a and 2b, and discriminates the front and back of the paper sheet 21 conveyed between the conveyance belt 2a and the conveyance belt 2b.

Reference numeral 3 denotes a non-reversing conveyance path through which a sheet (hereinafter, referred to as a non-reversing sheet 22) determined to be facing up by the discriminating unit 2 is conveyed. Transport belts 3a and 3b. The transport belt 3a is endless and is hung on pulleys 3c to 3h. In addition, the transport belt 3
b is also endless and is hung on the pulleys 3i to 3k so as to face the transport belt 3a.

Reference numeral 4 denotes a reversing conveyance path on which a sheet (hereinafter, referred to as a reversing sheet 23) determined to be turned back by the discriminating section 2 is conveyed. ,
4b, 4c, a reversal pool section 6, and a guide roller 7. The transport belt 4a is endless and is hung on pulleys 4d and 4e. The transport belt 4b is also endless,
It is hung on the pulleys 4f and 4g. Further, the transport belt 4c is also endless and is hung on the pulleys 4h to 4k.

The reversing pool section 6 includes a carrying-in guide frame 6a for guiding the reversing sheet 23 carried by the carrying belt 4a and the carrying belt 4b, a carrying belt 4b and a carrying belt 4b.
c, the carrying-out guide frame 6b for guiding the reversing sheet 23 carried out, and the conveyance belt 4a and the conveying belt 4b stop the conveyance of the reversing sheet 23 conveyed along the carrying-in guide frame 6a. Inverted paper sheet 23 along 6b
6c is transported by the transport belt 4b and the transport belt 4c. The distance from the carry-in section 6d and the carry-out section 6e to the stopper 6c is set to be slightly shorter than the length of the inverted sheet 23.

The guide roller 7 is provided coaxially with the pulley 4f, and has a tongue piece 7a made of a flexible member having a length protruding from the outer periphery thereof from the surface of the conveyor belt 4b wound around the pulley 4f. Are provided. Blade 5
Is provided at a branch point 13 between the non-reversing conveyance path 3 and the reversing conveyance path 4, and is rotatable in the direction of the arrow CC 'around the fulcrum 5a. This blade 5 sends the non-reversed sheet 22 to the non-reversed conveyance path 3 by rotating in the direction of arrow C based on the discrimination signal from the discriminator 2c, and reversing the sheet by rotating in the direction of arrow C '. 23 is fed into the reverse conveyance path 4.

Reference numeral 9 denotes a merging conveyance path in which a part of the conveyance belt 3a forming the non-reversing conveyance path 3 and a part of the conveyance belt 4c forming the reversing conveyance path 4 are arranged to face each other. Is transported along the merging guide frame 9a, and is sandwiched between the transport belt 3a and the transport belt 4c. To join.

Reference numeral 10 denotes an optical sensor provided near the junction 12 between the non-reversing conveyance path 3 and the reversing conveyance path 4 on the merging conveyance path 9, and a paper sandwiched between the conveyance belt 3a and the conveyance belt 4c. The light-emitting element 10a and the light-receiving element 10b are arranged with the merging conveyance path 9 interposed therebetween so that the optical axis passes through the leaves. 11 is a control unit connected to the optical sensor 10,
The control unit 11 determines from the change in the output of the light receiving sensor 10b whether or not the paper sheets passing through the merging and conveying path 9 are conveyed in an overlapped manner, and counts the number of sheets according to the overlap, so that the merged conveyance is performed. The number of sheets conveyed along the path 9 is managed.

FIG. 2 is a perspective view showing the structure of the guide roller. A plurality of the pulleys 4f described above are fixed on the shaft 14 at predetermined intervals, and a transport belt 4b is hung on each pulley 4f. The guide roller 7 is alternately fixed to the shaft 14 with the pulley 4f. When the shaft 14 rotates by receiving a driving amount from a driving unit (not shown), the pulley 4f and the guide roller 7 simultaneously rotate in the same direction.

The tongue pieces 7 provided on each guide roller 7
a has a length protruding from the surface of the transport belt 4b wound around the pulley 4f and is made of a flexible material, so that it can bend. In addition,
As described above, a plurality of transport belts 4b and pulleys 4f are arranged side by side in the horizontal direction, and the other transport belts and pulleys have the same configuration.

FIG. 3 is a waveform diagram showing a change in the output of the optical sensor. The operation of the paper sheet reversing device of this embodiment will be described below. First, the paper sheet 21 is transported to the discriminating unit 2 by a transport unit (not shown). In the discriminating unit 2, the discrimination unit 2c determines whether the paper sheet 21 is facing up or down, while being conveyed by being sandwiched between the transport belt 2a and the transport belt 2b.

When the discrimination device 2c determines that the fed sheet is face down, the blade 5 is rotated in the direction of arrow C 'about the fulcrum 5a by driving means (not shown) to convey the sheet. The path is switched to the reverse transport path 4 direction. Thus, the sheet transported between the transport belts 2a and 2b is sent to the reverse transport path 4.

First, the inverted paper sheet 23 is transported by the transport belt 2a,
It is fed between the conveyor belts 3a and 4a from between 2b. As described above, since the blade 5 is rotating in the direction of the arrow C ′, the reversing sheet 23 is transported on the blade 5 and guided to the reversing pool 6. The reversing sheet 23 guided to the reversing pool section 6 is sandwiched between the transport belts 4a and 4b, and is transported along the carry-in guide frame 6a. At this time,
Of the portions of the tongue pieces 7a provided on the guide roller 7 that protrude from the transport belt 4b, the portions that protrude toward the opposing transport belt 4a are formed by the inverted paper leaf 23 sandwiched between the transport belts 4a and 4b. It is pushed and bent.

When the reversing sheet 23 is conveyed along the carry-in guide frame 6a by the conveying belts 4a and 4b, the leading end of the reversing sheet 23 hits the stopper 6c. At this time, the rear end of the inverted sheet 23 is still sandwiched between the conveyor belts 4a and 4b, and the inverted sheet 23 is deflected by being further conveyed. When the rear end of the inverted paper sheet 23 passes between the conveyor belts 4a and 4b, the rear end of the inverted paper sheet 23 enters between the tongue pieces 7a of the guide roller 7. The guide roller 7 rotates in the direction of arrow A together with the pulley 4f, and the rotation of the guide roller 7 causes the rear end of the reversing sheet 23 to be guided toward the carry-out guide frame 6b while bending. Inverted paper leaf 2
When the rear end of the sheet 3 is guided toward the carry-out guide frame 6b, the rear end of the inverted sheet 23 is sandwiched between the transport belts 4b and 4c.

As a result, the inverted paper sheet 23 is transported by the transport belt 4
b, 4c, the paper is conveyed from the rear end side, whereby the inverted paper sheet 23 turned upside down is turned upside down, and the inverted paper sheet 23 turned upside down is conveyed by the conveying belts 4b, 4c into the merged conveyance path 9. Transported to On the other hand, when the discrimination device 2c determines that the sent paper sheet is facing up, the blade 5 is rotated in the direction of arrow C about the fulcrum 5a by a driving means (not shown), and the conveyance path of the sheet is set to the non-turned direction. The direction is switched to the reverse conveyance path 3 direction.

Thus, the sheet transported between the transport belts 2a and 2b is sent to the non-reversed transport path 4.
The non-reversed sheet 22 is first sent between the conveyor belts 2a and 2b and between the conveyor belts 3a and 4a. As described above, since the blade 5 is rotating in the direction of arrow C, the non-reversed paper sheet 22 is transported by the blade 5 to the pulley 3.
d, and is sandwiched between the transport belts 3a and 3b. Then, the sheet is conveyed by the conveying belts 3a and 3b to the merging conveying path 9 without being turned upside down.

Here, the distance of the non-reverse transport path 3 and the reverse transport
The distance of the path 4 is such that the preceding reversal sheet 23
Transit time T₁But a subsequent non-inverted sheet following this
The time T when 22 passes through the non-reversing conveyance path 3_TwoAnti-preceding
Delay time of the subsequent non-reversed paper sheet 22 with respect to the paper sheet 23,
That is, the sheet pitch T_ThreePlus time T₁= T _Two
+ T_ThreeThe distance of the non-reversing conveyance path 3 is shorter so that
Is set.

That is, in the case where the non-inverted sheet 22 is conveyed in succession with the inverted sheet 23 preceding, the preceding inverted sheet 23 and the subsequent non-inverted sheet 2 following the preceding inverted sheet 23 are conveyed.
2 are set to overlap at the junction 12.
However, in actuality, since the pitch T ₃ of the paper sheet varies, the preceding paper sheet and the succeeding paper sheet following the preceding paper sheet are conveyed along the merging conveyance path 9 without overlapping at the merging point 12. In some cases.

The reversing sheet 23 and the non-reversing sheet 22 that have joined at the joining point 12 are conveyed along the joining conveying path 9 and pass through the optical axis of the optical sensor 10 on the way. At this time, if the reversing sheet 23 and the non-reversing sheet 22 pass through the optical sensor 10 without overlapping, the output of the optical sensor 10 indicates the amount of light reaching the light receiving element 10b from the light emitting element 10a. As shown in FIG. 3, V _a
→ decreases as the V _c.

On the other hand, when the inverted sheet 23 and the non-inverted sheet 22 overlap and pass through the optical sensor 10 in two sheets, the output of the optical sensor 10 is changed from the light emitting element 10a to the light receiving element 10b.
The amount of light reaching because for dividing decreasing transmission two paper, as represented in FIG. 3, decreases as V _a → V _b. Here, when the number of sheets is one and two, the amount of transmitted light is smaller when the number of sheets is two, so that the voltage value output from the optical sensor 10 is more overlapped than when the number of sheets is one. Is lower ( _Vb < _Vc ).

[0030] Thus, using the difference ΔV between the amount of transmitted light V _b and V _c at the time of paper passage, the control unit 11, it is possible to determine whether the paper sheet has passed overlaps what has passed one . For example, the control unit 11 obtains in advance the output of the optical sensor 10 when the number of sheets is one and the output of the optical sensor 10 when the number of sheets overlaps, and uses this as a reference value. Then, by comparing the output with the output of the optical sensor 10 obtained when the sheet actually passes, it is determined whether the sheet has passed one sheet or overlapped.

When the controller 11 determines that the number of sheets is one, the controller 11 counts the number of sheets as one. When it determines that the sheets overlap, the controller 11 counts the number of sheets as two. The number of sheets transported is counted accurately. As described above, the optical sensor 10 is provided immediately after the junction 12 in the merging and conveying path 9, and it is determined from the output of the optical sensor 10 whether the number of sheets conveyed in the merging and conveying path 9 is one or overlapping. By accurately counting the number of sheets passing through the merged conveyance path 9 and managing the number of sheets based on the counted number, it is possible to detect whether the sheet is normally conveyed.

For example, the front and back of a sheet is detected from the output of the discriminator 2c, and the number of sheets passed is counted.
Thereafter, as described above, the number of sheets passing through the merged conveyance path 9 is counted from the output of the optical sensor 10, the two are compared, and the sheets before being sorted to the non-reversed conveyance path 3 and the reversed conveyance path 4 are counted. By judging whether or not the number of sheets and the number of sheets after merging match, if there is a difference between the two, it is determined that a conveyance abnormality such as a jam has occurred on the conveyance path in the front / back reversing device. Can be determined. If there is no difference between the two, it can be determined that the paper sheet is normally conveyed in the front / reverse device.

As described above, since the management of the number of paper sheets can be reliably performed, occurrence of a conveyance abnormality such as a jam in the middle of the conveyance path can be detected. The optical sensor 10
Instead of using the difference in the voltage value due to the difference in the amount of transmitted light as the output of
It is also possible to determine the double feed using the length of the paper sheet in the transport direction.

That is, the inverted sheet 23 and the non-inverted sheet 22
When they merge and overlap with each other, they do not always overlap exactly, and a shift may occur. If there is a shift in the overlapped sheets, the length in the transport direction becomes longer than the length in the transport direction when one sheet is used. This gives 1
Sheet of paper leaves time T _a required to pass through the optical sensor 10 are overlapped paper sheets a time required for passing through the optical sensor 10 when the T _b, the T _b> T _a.

[0035] Thus, using the difference between the paper sheet passage time T _a and T _b, the control unit 11, it is possible to determine whether the paper sheet has passed overlaps what has passed one. For example, the passage time for one sheet is obtained in advance, and this is set as a reference value.
The time required to pass through the optical sensor 10
Output counts the V _a → V _b, the time is changed to V _c by detecting the paper, as compared with the count value and the reference value, the sheet 1 the closer the count value to the reference value It is determined that the sheets are the same, and if they differ by a predetermined amount or more, it is determined that the sheets overlap.

When the controller 11 determines that the number of sheets is one, the controller 11 counts the number of sheets as one, and when determining that the sheets overlap, counts the number of sheets as two. Can be accurately counted, and by managing the number of sheets in the same manner as described above, it is possible to detect a sheet conveyance error. Furthermore, by using both the difference in the amount of transmitted light and the difference in the length of the sheet in the transport direction,
It may be determined whether the number of sheets is one or overlapping.

That is, the controller 11 controls the optical sensor 10
, It is determined whether the number of sheets is one or overlapping based on both the change in the size and the time of the change. With this, it is possible to determine whether the sheets are one sheet or overlapping,
It can be done more reliably. Further, in each of the above embodiments, the thickness or length of the paper sheet is detected using the optical sensor. However, even if a mechanism that can directly contact the paper sheet and detect the thickness of the paper sheet is used, the paper sheet may be used. Can be determined whether or not overlaps.

FIG. 4 is a side view of a main part of a paper sheet reversing device according to another embodiment of the present invention. In the drawing, reference numerals 31a and 31b denote thickness detecting rollers provided in the merged conveyance path 9, reference numeral 32 denotes a bracket for rotatably supporting the thickness detecting roller 31a at one end thereof, and reference numeral 33 denotes the bracket 3
2 is a shaft supporting the other end side, and 34 is the shaft 3
3 is a sensor that detects the amount of rotation of the sheet 3. The sheet conveyed through the merged conveyance path 9 is sandwiched between the detection rollers 31a and 31b and passes therethrough.
a is pushed up by the thickness of the sheet, the shaft 33 rotates through the bracket 32 by the movement of the detection roller 31a, and the rotation amount of the shaft 33 according to the sheet thickness is detected by the sensor. It has become. In addition,
The bracket 32 connects the detection roller 31a to the detection roller 31.
It is urged by a spring or the like (not shown) in the direction of pressing against b.

Here, since the thickness is larger when the number of sheets is two than when the number of sheets is one, the amount by which the detection roller 31a is pushed up is large and the amount of rotation of the shaft 33 is also large. Therefore, from the difference in the amount of rotation of the shaft 33,
It can be determined whether the sheets are overlapping or overlapping. For example, the rotation amount of the shaft 33 when the number of sheets is one and the rotation amount of the shaft when the number of sheets is two are determined in advance and set as a reference value. The value is compared with the amount of rotation of the shaft when the sheet actually passes, and it is determined whether the number of sheets is one or more.

When the control unit determines that the number of sheets is one, the control unit counts the number of sheets as one, and when determining that the sheets are overlapped, counts the number of sheets as two. The number of conveyed paper sheets can be accurately counted, and by managing the number of paper sheets in the same manner as described above, it is possible to detect the conveyance abnormality of the paper sheets.

[0041]

As described above, according to the present invention, a sensor for detecting whether or not sheets conveyed in the merged conveyance path are overlapped is provided on the merged conveyance path, and the sheets are conveyed in an overlapping manner. The number of sheets conveyed along the merged conveyance path is counted by determining how many sheets are conveyed by judging whether or not the sheet is conveyed. When the paper sheet and the paper sheet conveyed on the non-reversing conveyance path are fed into the merged conveyance path, whether they overlap or not overlap, the number of sheets can be counted accurately, and the reversing paper sheet and the non-reversing paper sheet can be counted. This has the effect that it is possible to accurately manage the number of sheets after the reversing paper sheets are merged, and it is possible to manage the number of sheets after the merged paper sheets in the transport path in the sheet reversing device. It is possible to detect the occurrence of a paper transport error Has an effect, it is possible to provide a highly reliable sheet reversing apparatus compact.

[Brief description of the drawings]

FIG. 1 is a side view illustrating a configuration of a sheet reversing device according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a configuration of a guide roller.

FIG. 3 is a waveform chart showing a change in output of an optical sensor.

FIG. 4 is a side view of a main part of a sheet reversing device according to another embodiment of the present invention.

[Explanation of symbols]

 2 Discrimination unit 3 Non-reversing transport path 4 Reversing transport path 5 Blade 9 Merging transport path 10 Optical sensor 11 Control unit 12 Merging point

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B65H 29/58 B65H 7/12 G07D 9/00 416

Claims (5)

(57) [Claims] 1. A discriminating unit for discriminating the front and back of a sheet, a non-reversing conveyance path for conveying a sheet discriminated to be upside down by the discriminating unit without reversing the sheet, and a sheet discriminated to be backside up. A reversing transport path for reversing and transporting the paper in a face-up direction, a sorting mechanism for distributing the paper sheet to the non-reversing transport path or the reversing transport path based on the determination result in the discriminating unit, and the non-reversing transport path and the reverse transport. A sheet reversing device having a merging and conveying path that merges and conveys the sheets that have passed through the path, wherein the merging conveyance is performed on a merging conveyance path near a junction of the non-reversing conveyance path and the reversing conveyance path. A sensor for detecting whether or not the sheets conveyed on the road are overlapped is provided, and from the output of the sensor, it is determined whether or not the sheets are overlapped. Determine if the sensor has passed And a control unit for counting the number of sheets conveyed through the combined conveyance path, wherein the sheet front / back reversing device is provided. 2. The paper sheet reversing device according to claim 1, wherein an optical sensor is used as the sensor, and the control unit is configured to determine a light transmission amount and a paper when one sheet is detected by the optical sensor. From the thickness of the paper sheet determined by the difference in the amount of transmitted light when the leaf is overlapped, the number of the paper sheets is determined by determining whether or not the paper sheets are overlapped, and the paper is conveyed through the combined conveyance path. A sheet reversing device for counting the number of sheets. 3. The paper sheet reversing device according to claim 1, wherein an optical sensor is used as the optical sensor, and the control unit detects a front end of the paper sheet being conveyed by the optical sensor and then moves the rear end. From the length of the paper sheet in the transport direction obtained from the paper sheet transit time, which is the time required for detection, the number of the paper sheets is determined by determining whether or not the paper sheets are overlapped,
A sheet reversing device for counting the number of sheets conveyed along a combined conveying path. 4. The paper sheet reversing device according to claim 1, wherein an optical sensor is used as the sensor, and the control unit is configured to determine a light transmission amount and a paper when the number of sheets detected by the optical sensor is one. The thickness of the sheet, which is determined by the difference in the amount of light transmitted when the leaves overlap, and the time required for the optical sensor to detect the leading edge of the transported sheet and to detect the trailing edge of the sheet. From the length of the paper sheet in the conveyance direction obtained from the passage time, the number of the paper sheets is determined by determining whether or not the paper sheets are overlapped, and the number of the paper sheets conveyed through the combined conveyance path is counted. A sheet reversing device for reversing paper sheets. 5. The sheet reversing device according to claim 1, wherein the sensor is a roller that is in contact with the conveyed sheet and that can move according to the thickness of the sheet, and a sensor that detects the amount of movement of the roller. And the control unit determines that the paper sheet is 1
From the thickness of the sheet obtained from the difference in the amount of movement of the roller when the sheet overlaps with the sheet, the number of the sheets is determined by determining whether or not the sheets are overlapped, and the combined conveyance path is determined. A sheet reversing device for counting the number of conveyed sheets.