JPS63258347A - Overlapping feed detecting device for sheet material - Google Patents

Abstract

PURPOSE:To accurately detect an overlapping feed, by a method wherein, through comparison of the length of an original under conveyance, measured by a length measuring means, with the length of an original set in a conveyance part, detected by a length detecting means, the overlapping feed of an original and the like is detected. CONSTITUTION:A rear end regulating plate 1a of an original feed rate 1 is set in a manner to be adjusted to the rear end of an original (a), and sizes A4, B4, and A3 are detected by means of sensors 4-6. The original (a) is then fed to an upper conveyance passage D through a handling roller 13 and conveyance rollers 14 and 15 by means of a feed roller 3. When backward movement is detected by means of a sensor 35, it is stopped once, and it is fed to a lower conveyance passage E by rolling. In which case, in a first overlapping feed detecting part 30, when the forward end of the original is detected by means of a sensor 33, a rotary encoder mounted to a conveyance roller 14 counts until a rear end thereof is detected by means of a sensor 32, and the length of the original is measured, and the measuring result is compared with a detecting length on a tray 1 to detect an overlapping feed. Further, a second overlapping feed detecting part 31 sucks the original (a) from both sides of a guide plate 36 while the original is stopped once, and with a sensor 28 also operated, it is detected that an overlapping feed occurs.

Description

[Detailed Description of the Invention] Cliff W 1 (7) f + J J Seven Chains The present invention is suitable for a feeding device that automatically conveys a document as a sheet + A to a micro camera that creates a micro film, a copying device, etc. The present invention relates to a double feed detection device for sheet materials provided in a.

When documents are automatically fed into the aforementioned micro camera or copying device, double feeding of documents causes a serious problem. In particular, with a micro camera, a large number of originals are printed on a roll film and then developed all at once, so if multiple originals are fed during photographing, some originals may not be photographed. For this reason, in order to copy double-fed originals that have not been photographed in the specified order, it is necessary to start shooting again from the beginning or cut the film and re-edit, creating a very troublesome situation. do.

Therefore, a device has been proposed to detect double feeding of documents, which causes this problem.However, the conventional double feeding detection device for sheet The sheet is fed between a part of the conhair that conveys the sheet and a cam follower installed in cooperation with the cam follower, and the cam follower does not operate within the thickness of one sheet, and due to double feeding of sheets, the sheet is fed further. When the above operation is performed, the actuator for repelling the sheet is actuated via the follower arm.

In addition, the method disclosed in Japanese Patent Application Laid-open No. 46-4185 is that an illumination device and a photosensitive device are provided on both sides of a sheet passage, and when the sheet passes through the sheet, the amount of light from the illumination device that is received by passing through the sheet is detected by the photosensitive device. The apparatus stores the information at the same time as it is detected by the device, and when the next sheet is passed, the memorized amount of light is compared with the amount of transmitted light of the sheet to determine whether or not double feeding is occurring. This is what I did.

However, in the conventional double feed detection device for sheet materials mentioned above, in the former, the cam follower, which is the detection part, operates depending on the thickness of the sheet, and in the latter, Also, 1
Since the amount of transmitted light of one sheet is memorized and compared with the amount of transmitted light of the next sheet, when a sheet with a thickness different from the previously set sheet thickness is conveyed, especially thin and thick When a mixture of sheets is continuously and randomly conveyed, both of the double feed detection devices described above have a problem in that they malfunction and cannot be detected accurately.

Therefore, in view of the above-mentioned problems, the present invention has been developed so that even when a mixture of thin and thick sheets is conveyed continuously,
It is an object of the present invention to provide a double feeding detection device for sheet materials that can accurately detect double feeding.

In order to achieve the above object, the double feed detection device for sheet materials of the present invention includes a length detection means for detecting the length of the sheet materials set in the conveyance section, and a means for determining the length of the sheet materials set in the conveyance section. A length measuring means for measuring the length from the leading edge to the trailing edge of the sheet material inside, and comparing the length of the sheet material detected by the length detecting means with the length of the sheet material measured by the length measuring means, The present invention is characterized by comprising a comparison/determination means for determining whether or not the sheet materials being conveyed are being fed in duplicate based on the difference.

According to the above configuration, when documents, etc. as sheet materials are being conveyed in a double-feed state with a slight deviation, the distance from the leading edge to the trailing edge of the document being conveyed as measured by the length measuring means. The length up to
When compared with the length of the originally set original document detected by the length detection means, it is larger by the amount of deviation, and based on the difference, the comparison judgment means detects double feeding of the original documents, etc.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail. FIG. 1 shows a schematic configuration diagram of a micro-photographing device equipped with a double-feed detection device for sheet materials as an embodiment of the present invention. The micro-photographing device is broadly divided into an automatic document feeder A that supplies a document a as a sheet material, an optical device B that illuminates the document a to create a document image, and an optical device B that photographs the document image on a microfilm. It consists of a photographing device C.

The automatic document feeder A is provided with a document supply tray 1 that holds a plurality of documents A in a stacked state at the top of the main body of the device, and a document push-up plate 2 is attached to the document supply tray L. The document pushing plate 2 is configured to press the placed document a against a feed roller 3 disposed above, and the feed roller 3 takes in the document a one by one from above. As shown in FIG.
3 is turned on by a magnet (not shown) built into the rear end regulating plate 1a that holds the rear end when the
Sensors 4, 5.6 are installed. These three sensors 4, 5, and 6 are used for document sizes A4 and A4 from the left in FIG.
B4. It is installed in a position corresponding to A3.

Then, as described above, the document a taken in by the feed roller 3 is conveyed by each row, which will be described below, provided along the upper conveyance path and the lower conveyance path E of the automatic document feeder A. . On the upper conveyance path, a pair of separating rollers I3 are arranged symmetrically adjacent to the feed roller 3 and whose lower side is rotatable in reverse, and two sets of conveyance rollers downstream thereof. 14.15 are provided. The lower conveyance path E starts from a position slightly upstream of the conveyance roller 15 and separates downward into a seven-shape shape, then bends into a U shape, becomes horizontal, and continues to the document discharge side. It is formed as follows.

A conveyance roller 16 and a conveyance roller 17 are arranged in the U-shaped portion of the conveyance path E, and an illuminated portion of the document a consisting of a platen glass 18 and a conveyance heald 19 is provided continuously from the conveyance roller 17. And this transport heald 19
A discharge roller 20 is provided at the rear end to remove the photographed document a.
is delivered to the rear discharge tray 21. In addition, the above U
The second section of the lower conveyance path E, which is bent in a letter-like shape, serves as an auxiliary conveyor for reversing the document a by reversing the conveyor belt 19 and the conveyor roller 17 when double-sided photographing is performed. It is formed in road e. Furthermore, Mylar 22, 23, and 24 are provided at the boundaries of the above-mentioned upper transport path and lower transport path E, and between the lower transport path E and the auxiliary transport path e, to prevent the document a from being sent backwards. Sensors 25.2 are installed at each main part of the conveyance path to detect the presence or absence of document a and detect jams.
6.27 is provided.

As shown in FIG.
a first double-feed detection unit 3 for detecting double-feed of document a during
Further, a second double feed detection unit is provided between the downstream conveyance roller 14 and the conveyance roller 15 to detect double feed again in case the first double feed detection unit 30 cannot detect the double feed. A section 31 is provided.

The first double feed detection unit 30 is located on both sides of the conveyance roller 14.
Distance I! , two sensors 32 and 33 for detecting the conveyance of the document a, which are separated by a distance of , consists of more.

The second double feed detection unit 31 includes a trailing edge detection sensor 35 for detecting the trailing edge of the original document a downstream of the conveyance roller 14, and an opening 36a, and faces both sides of the upper conveyance path. A pair of guide plates 36 provided in the state and a distance I! downstream from the rear end detection sensor 35! two sensor levers 37 with tips 37a disposed at positions spaced apart by 2;
A photo sensor 38 is provided with a light emitting part and a light receiving part on both sides of the other end side 37b of both sensor levers 37, and a suction cup 39 provided at the tip is transported upward from behind the opening 36a of the guide plate 36. It is composed of a pair of document suction sections 40 that are configured to move forward and backward within the path, and a suction section moving mechanism 45 that will be described later.

The document suction unit 40 has a suction cup 3 as shown in FIG.
9, and a suction pipe 42' connected to the other end of the suction pipe 41. be exposed. The suction part moving mechanism 45 is fixed to the main body of the apparatus and includes a guide guide 46 that slidably supports the suction pipe 41, and a support ring 41a attached to the guide guide 46 and the suction pipe 41. A spring 47 that is fitted and urges the suction cup 39 in the backward direction, and a pin 4 provided on the suction pipe 41.
1b has an elongated hole 48a at the tip, and an elongated hole 48b is formed at the other end, and is rotatably supported around the center, and is arranged symmetrically with each other. 48, 48, and a plunger 49 which has a pin 49a engaged in the overlapping state of the elongated holes 48b of both levers 48 and is driven by a solenoid 50. According to this configuration, when the solenoid 50 is actuated, the plunger 49 pulls the ends of the two levers 48.48 through the two throw holes 48b, 48b, and the levers 4.8.
Each end of 48 is a long hole 48a.

The suction pipe 41 is advanced from 48a through the pin 41b of the suction pipe 41. The suction pipe 41 moves in the direction of the upper conveyance path against the spring force of the spring 47, and presses the suction cup 39 attached to the tip of the suction pipe 41 against the document a. At this time, when the suction device (not shown) is driven to suck the document a onto the suction cup 39 via the suction pipe 42, and then the solenoid 50 is turned off, the pulling force on the lever 48 by the plunger 49 is eliminated, so that the spring Suction pipe 41 with elastic force of 47
is pulled back, and the suction cup 39 moves in the backward direction while adsorbing the document a.

As shown in FIGS. 3 and 6, the photosensor 38 has a light emitting section and a light receiving section, and the end 37b of the sensor lever 37 is inserted between the light emitting section and the light receiving section, so that the light receiving section is normally shielded from light. . The end 37a of the sensor lever 37 protruding into the upper conveyance path is moved by the document a when the suction cup 39 sucks the document a and retreats, so that the end 37b of the sensor lever 37 is moved by the document a. The light shielding is released and the sensor 38 is turned on. However, if only one sensor 38 is turned on, document a is transported as a single sheet and is not multi-feeded, and it is not until both sensors 38 are turned on that the document a is transferred via a well-known AND gate or the like. The system is configured so that multiplexed signals are emitted.

Note that the double feed detection section 31 includes a trailing edge detection sensor 35, a document suction section 40, and a sensor lever 37 from the upstream side of the document a.
However, depending on the distance 12 between the rear end detection sensor 35 and the tip 37a of the sensor lever 37, the positions of the document suction unit 40, the sensor lever 37, and the photo sensor 38 may be replaced. can.

Optical device B includes the platen glass 18 and the conveyor bell)
A lamp 53 for illuminating the document a conveyed from below 19, and two reflecting mirrors 54 and 55 for introducing the document image generated by the illumination of the lamp 53 into the photographing device C.
The reflecting mirrors 54 and 55 are composed of:
Each can be adjusted forward and backward to adjust focus.

Further, the photographing device C includes a photographing lens 56 that condenses the original image from the optical device B, and a transport section 58 that transports a microfilm 57 for recording at a predetermined pitch.

The operation of the micro-photographing device having the above configuration will be explained. In this micro-photographing device, when a document a is placed on the document supply tray 1 with the photographing surface facing upward, the trailing edge regulating plate la of the document supply tray is adjusted to match the rear edge of the document a. be done. The example in FIG. 2 shows an example of an A4 size document a, and the sensor 4 is turned on by the magnet of the rear end regulating plate 1a.

Then, the document push-up plate 2 is driven to press the document a against the feed roller 3.
feeds the documents a into the upper conveyance path in order from the top, and the next separating roller 13 prevents double feeding. Then, the document a is sent from the conveyance roller 14 to the conveyance roller 15, and when the trailing edge detection sensor 35 detects the trailing edge of the document a, the rotation of the conveyance roller 15 is stopped and then reversed. Then, the document a is guided to the lower conveyance path by the mylar 22 installed at the entrance of the lower conveyance path E, and sent to the platen glass 18 and the conveyance heald 19 via the conveyance rollers 16 and 17, and the photographing is completed. Then, the paper is discharged from the discharge roller 20 onto the discharge tray 21. In the case of a document a with writing on both sides, it is captured between the platen glass 18 and the conveyance heald 19 and photographed, then the conveyance belt 19 is reversed, and the document a is guided to the auxiliary conveyance path e by the Mylar 24 and reversed. Then, the opposite side is photographed.

However, in the above-mentioned handling roller 13, since the handling rollers 13 use a pair of upper and lower row arms, for example, if three or more sheets are conveyed at once,
It is not possible to prevent document a from being fed multiple times, and a plurality of sheets are overlapped, or the second and subsequent sheets at the bottom are transported with a slight delay. Therefore, such double feeding is avoided in the first example of this embodiment. This is reliably detected by the second double feed detection sections 30 and 31.

In the first double feed detection unit 30, when the document a is conveyed, the sensor 33 on the downstream side of the conveyance roller 14 detects the leading edge of the document a, and at the same time, the rotary encoder 34 attached to the conveyance roller 14 starts counting pulses. . This counting continues m until the sensor 32 on the upstream side of the conveyance roller 14 detects the trailing edge of the document a, thereby measuring the length of the document a. Let K be the measurement result and L be the length of document a detected by the sensor 4 described above. If K = L, double feeding has not occurred, but the distance between the sensors 32 and 33 is 7! Since they are separated by 1, if K+A,>L, it is determined that there is a double feed. However, the length of document a varies, and the detection and measurement results also contain errors, so if you do not allow some margin in the measurement results, it will be determined that double feeding has occurred even when only one sheet has been fed. Therefore, if the allowable value is set to 13, a determination is made that K-Iβ, > 1-+β3. In this embodiment, the distance between the sensors 4 and 5 and the above-mentioned allowable value are set to be equal to β1-β3-2 (ln), and when K>L, it is determined that double feeding is occurring.

FIG. 7 shows a configuration for comparing and determining the detected length L of the document a and the measurement results. This comparison and judgment means is performed by the CPU 60,
Sensors 4 and 5.6 detect the size of the document a via an interface 61, and a sensor 81 detects the length of the document a to be conveyed.
The CPU 60 is connected to the measuring sensors 32 and 33 and the rotary encoder 34, as well as to the ROM 62 and RAM 63.
Send a stop signal to stop the conveyance.

The operation of this comparison/judgment means will be explained with reference to the flowchart I- shown in FIG. After initializing the contents of the CPU 60 and RAM 63 (step S■), each sensor 4. ，
5.6 and sensors 32 and 33 can be detected (enabled)
state (step S2). Next, the sensors 4 and 5
．． Detecting the size of document a based on the signal from 6,
The length L of the document a is measured from a numerical value stored in advance in the RAM 63 (step S3). Then, conveyance roller 1
Step S4 is repeatedly executed until the sensor 33 on the downstream side of No. 4 detects the leading edge of the document a, and the sensor 33 is turned on.
At the same time, the sensor 32 on the upstream side of the conveyance roller 14
Check that document a is also detected in step S5).
The rotary encoder 34 starts counting the number of pulses (step 36). Then, while the document a is being conveyed, that is, while both sensors 32 and 33 are detecting the document a, counting of the number of pulses is continued (steps 34 to S6), and the trailing edge of the document a is continuously counted. When it reaches the sensor 32, the sensor 32 is turned off and the process advances from step S5 to step S7 on the right.

In step S7, the length of the document a is measured using the number of pulses described above to calculate the length K. Next, the measured length K of document a is compared with the length L when document a was first set, and it is determined that K>L (step 38).
. If K≦, there is no double feeding, so the document a continues to be conveyed, and the operations of detecting, measuring, and comparing and determining the length of the single document a currently being conveyed are completed. Step S
If it is determined in step 8 that K>L, the document a is being fed in duplicate, so the process advances to step S9 and outputs an output to the conveyance control section 64' to stop the conveyance, and also outputs, for example, a double feed signal. do.

Next, the operation of the second double feed detection section 31 is explained in FIG.
The explanation will be based on e). Document a is detected by the first double feed detection unit 30
When the trailing edge reaches the trailing edge detection sensor 35 after being fed through, the conveyance is temporarily stopped, and at this time, the second double feed detection section 31 is activated. That is, as described above, by turning on the solenoid 50, both suction cups 39 are opened.
The document A is plunged into the conveyance path from the center of the document A and brought into close contact with both sides of the document a, and the suction device is driven to perform suction (see FIG. 9).
b)).

Next, when the solenoid 50 is turned off, the suction cup 39 retreats due to the elastic force of the spring spring 47, pulling the document a to the guide plate 36 (FIG. 9(dl), and the photosensor 38 is turned on. When the document a is moved backward, the document a is blocked by the guide plate 36, loses its suction force, and returns to the conveyance path (FIG. 9(e)).

In this way, the first double feed detection section 30 and the second double feed detection section 3
1 detects double feeding, but sensor 32 and sensor 3
3 and the relationship between the distances β1 and 12 between the rear end detection sensor 35 and the sensor lever tip 37a, these distances are as follows: β2>β.

The relationship is set as follows. That is, as mentioned above, β,
is set equal to the allowable value β3 that is not considered to be electrical transmission, so by setting 12>121 as described above, for example, in the case of double feeding as shown in FIG. 10, the trailing edge detection sensor 35
When the document a detects the rearmost edge n of the document a and the conveyance stops, the length 14 between the rear edge n and the rear edge m of the double feed portion is longer than the length 12 of the rear edge detection sensor 35 and the sensor lever tip 37a. Even small double feeds that are not detected by the first double feed detector 30 can be reliably detected by the second double feed detector 31. In the second double-feed detection section 31, double-feed detection is performed by directly suctioning the document a from both sides with the document suction section 40, so that even if the above-mentioned deviation is small, double-feed can be sufficiently detected.

Note that the sensor 4 attached to the document supply tray 1 described above,
5.6 has a configuration that responds to magnets, but as is well known in copying machines, a plurality of sensors with protrusions are provided on the document supply tray 1, and the document size is detected by the document a pressing down on the protrusions. It can also be configured.

In the micro-photographing device of this embodiment, since the first double-feed detection section 30 and the second double-feed detection section 31 are provided, it is possible to reliably detect double-feed in any state when the document a is conveyed. This makes it possible to prevent serious situations such as omitted photography from occurring.

As described above, the sheet material double feed detection device of the present invention includes a length detection means for detecting the length of the sheet material, and a length detection means for detecting the length of the sheet material, and a length detection device for detecting the length of the sheet material from the leading edge to the trailing edge during conveyance. Since it is equipped with a length measuring means for measuring the length and a comparison judgment means for comparing the length measurement result with the length detecting means to determine double feeding, it is possible to prevent thick sheets and thin sheets from coexisting. Even if the length of each unit of sheet material is different, it is possible to measure the length of one unit of sheet material being transported and compare it with the length of the sheet material in the set state, and if the length of the sheet material being transported is long. double feed can be detected. For this reason, it is possible to prevent double feeding of originals to be photographed on sheet materials such as microfilm, and it is possible to photograph all originals in a predetermined order, which previously occurred. This eliminates the need to skip originals, and saves you the trouble of reshooting and editing. Therefore, when copying or creating microfilm from sheet materials, the work can be carried out efficiently.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a micro-photographing device equipped with a double-feed detection device for sheet materials as an embodiment of the present invention, and FIG.
The figure is a partial enlarged sectional view of the document supply tray of the double feed detection device, FIG. 3 is an enlarged side view of the double feed detection device, FIG. 4 is a front view of the conveyance roller and the rotary encoder attached to it, and FIG. 5 is an enlarged side view of the second double feed detection section, and FIG.
FIG. 7 is a perspective view of the main parts of the double feed detection section, FIG. 7 is a configuration diagram of a comparison and judgment means for processing signals from each sensor and rotary encoder, FIG. 8 is a flowchart of signal processing in the comparison and judgment means, and FIG. 9 Figures fa) to (1111 are side views each illustrating the operation of the second double feed detection section, and Figure 10 is a side view showing a state in which documents are double fed. 1... Original supply tray, 2 ...Manuscript push-up board, 4
．． 5.6...Sensor, 30...First double feed detection section, 31...Second double feed detection section, 32.33...Sensor, 34...Low reencoder, 35... Rear end detection sensor, 36... Guide plate, 37...
Sensor lever, 38... Photo sensor, 39...
- Suction cup, 40... Document suction unit, 45... Suction unit moving mechanism, 60. CPU,
62-ROM. 63...RAM, A...automatic document feeder, a...manuscript, B...optical device,
C...Photographing device, D...Upper conveyance path, E.
...lower conveyance path, e...auxiliary conveyance path. Patent applicant: Minolta Camera Co., Ltd.

Claims (1)

[Claims] (1) Length detection means for detecting the length of the sheet material set in the conveyance section; Length measurement means for measuring the length from the leading edge to the trailing edge of the sheet material during conveyance; and Length detection means. Comparative judgment means for comparing the length of the sheet material detected by the sheet material with the length of the sheet material measured by the length measuring means, and determining from the difference whether or not the sheet material being transported is double fed. A double feed detection device for sheet materials, which is characterized by: