JPH05155471A - Document cassette feeding device having self-checking mechanism for sensor circuit - Google Patents

Abstract

PURPOSE:To self-check whether a sensor circuit by which a document cassette charged in a document cassette feeding device is detected is constantly normally functioned. CONSTITUTION:A document cassette feeding device has a plurality of stage parts, wherein document cassettes are charged, and is disposed to the side part of a cage movable in a given direction and provided with a check circuit 63 containing a sensor comprising at least a pair of a light emitting element and a light receiving element, arranged facing the stage part, and detecting a document cassette charged in the stage part. The check circuit 63 comprises an oscillation control circuit 67 to flicker and control the light emitting element of which a sensor is composed, and an oscillation circuit 65, and a detecting circuit 71 by which the lighting-ON state and lighting-OFF state of the light emitting element are detected through a signal amplifying circuit 69, based on a signal from the light emitting element of which a sensor is composed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an image reading apparatus,
The present invention relates to a document cassette feeding device including a self-check mechanism of a sensor circuit that selectively feeds a plurality of document cassettes holding read documents.

[0002]

2. Description of the Related Art In the fields of printing and plate making, an image scanning reading / reproducing system for electrically processing image information recorded on an original to make a film original for the purpose of rationalizing work processes, improving image quality, etc. It is used.

In this case, the image reading apparatus constituting the system performs two-dimensional reading of image information by carrying out main scanning while the read original positioned and stored in the original cassette is conveyed to the reading unit.

In such an image reading apparatus, in order to handle a large amount of read originals, it is desirable to connect an automatic feeder capable of automatically supplying a plurality of original cassettes. In addition, the automatic supply device is generally provided with a vertically movable cage having a plurality of stepped portions on which the objects to be supplied are loaded, and a desired object to be supplied is taken out by elevating the cage. It is configured to move to the mouth.

[0005]

By the way, in the automatic feeder, the original cassette is not correctly stored in the cage. For example, when the original cassette is lifted up and down while the original cassette is out of the cage, the original cassette moves around the peripheral wall of the cage. May come into contact with or be pinched and damaged.

Therefore, such an automatic feeder is provided with a sensor for detecting the position of the original cassette.
Further, by using this sensor, it is possible to detect the presence or absence of a document cassette in the stepped portion and determine whether or not the next document cassette can be loaded in the stepped portion.

However, if the circuit including the sensor has a malfunction, not only the original cassette is damaged but also the next original cassette is erroneously loaded on the stepped portion where the original cassette is already loaded. Etc.
Trouble may occur.

The present invention has been made to solve this type of inconvenience, and is capable of self-checking whether or not a sensor circuit for detecting a document cassette is functioning normally. An object of the present invention is to provide a document cassette feeding device including a mechanism.

[0009]

In order to achieve the above-mentioned object, the present invention is a document cassette feeding device for selectively feeding a plurality of document cassettes holding read documents to an image reading device. , A plurality of stepped portions on which the document cassette is loaded, disposed on a side portion of a cage movable in a predetermined direction, and composed of at least a pair of a light emitting element and a light receiving element arranged to face the stepped portion, A sensor for detecting a document cassette loaded on the stepped portion, a blinking control circuit for controlling blinking of a light emitting element forming the sensor, and a lighting state of the light emitting element based on a signal from the light emitting element forming the sensor. And a detection circuit for detecting an off state.

[0010]

According to the present invention, the document cassette feeding device having the sensor circuit self-checking mechanism is provided with the sensor for detecting the document cassette loaded in the device. Therefore, if the cage is moved so that the light-emitting element and the light-receiving element forming the sensor are not shielded from each other and the light-emitting element is made to emit light in this state, the emitted light reaches the light-receiving element, and the pseudo light is emitted. Therefore, it is detected as an empty state in which the document cassette is not loaded. Similarly, if the light emitting element is turned off in this state, it is detected that the document cassette is loaded. This allows the sensor circuit to be self-checked.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A document cassette feeding device having a sensor circuit self-checking mechanism according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view of the original cassette feeding apparatus of this embodiment, and FIG. 2 is a perspective view of the original cassette feeding apparatus with the upper and middle lid members removed.

The original cassette feeding device 10 is surrounded by a casing 12, and has a cage 16 for accommodating the original cassette 14, an elevating means 17 for elevating and lowering the cage 16, and an original cassette accommodated in the cage 16. And a cassette transport mechanism (described later) for supplying 14 to the image reading device 20 to which the original cassette supply device 10 is connected.

The document cassette 14 supplied to the document cassette supply device 10 and the image reading device 20 is constructed as shown in FIG. That is, the document cassette 1
Reference numeral 4 denotes a transmissive read original document 26 held between two supporting glass plates 24 surrounded by a frame body 22 having a substantially rectangular shape. V-shaped grooves 28a, 28b extending along the ridge are defined. A cassette identification unit 30 for identifying the document cassette 14 and the read document 26 held in the document cassette 14 is provided on the upper surface of the front end of the frame 22 in the transport direction.
Is provided. The cassette identification unit 30 is used for the original cassette 14 and the read original 2 held in the original cassette 14.
6 is configured by combining a plurality of light transmitting portions 32 and light shielding portions 34.

In FIG. 4, the image reading apparatus 20 includes an insertion detecting means 38 such as a photo interrupter disposed near the communication port 36 formed in the casing 35, a cassette identifying means 40, and the original cassette 14 for the image. Reader 2
A transporting means 42 for transporting in 0 and an image reading section 44
With. The insertion detecting unit 38 detects that the document cassette 14 has been inserted into the image reading device 20. Also,
The cassette identifying means 40 identifies the document cassette 14 and the read document 26 held in the document cassette 14, and is composed of, for example, a plurality of light emitting elements and light receiving elements in pairs. The conveying unit 42 conveys the document cassette 14 from the communication port 36 to the image reading unit 44, and has guide rollers 46 that engage with the grooves 28a and 28b on the side of the document cassette 14. The image reading unit 44 includes a light source 48.
And a light receiving element 50 such as a CCD, and a light source 48 that passes through the document cassette 14 conveyed to the image reading section 44.
An image is read by receiving light from the light receiving element 50.

Next, the structure of the original cassette supply device 10 will be described in detail with reference to FIGS. 1, 2 and 5 to 9.

As shown in FIG. 2, the casing 12 has a first lid portion 52 and a second lid portion 54 to which the upper and middle steps are detachable. A cassette insertion table 56 having a cassette insertion opening 18 defined therein is provided near the lower end of the first lid 52. A sensor 58 for detecting the insertion of the document cassette 14 is provided at one end of the cassette insertion table 56. Inside the first lid portion 52, a pair of guide rollers 5 is provided at a portion corresponding to the cassette insertion opening 18.
9 is provided (see FIGS. 1 and 5). The guide roller 59 guides the document cassette 14 inserted from the cassette insertion port 18 and carries it into the document cassette supply device 10.

The cage 16 is composed of a top plate 68, a bottom plate 70, and six guide bars 72 that support them in the casing 12 (see FIGS. 1 and 5). A plurality of guide rollers 74, which are spaced apart from each other by a predetermined distance, are axially supported by the respective guide bars 72. These guide bars 72 are four on one side surface of the document cassette 14 loaded from the cassette insertion port 18 and the other side surface. Two are arranged on the side. The guide rollers 74 pivotally supported by the guide bar 72 hold the document cassette 14 by engaging with v-shaped grooves 28a and 28b defined on both side surfaces of the document cassette 14. In this manner, the cage 16 can hold a plurality of adjacent upper and lower original cassettes 14 by a predetermined distance by the guide rollers 74.

On the upper surface of the top plate 68 of the cage 16, there is provided a guide portion 76 for holding the side surface of the document cassette 14 when the document cassette 14 is manually inserted. On the other hand, a light shielding plate 80 is fixed to the lower side portion of the top plate 68 substantially parallel to the insertion direction of the original cassette 14. In addition, the light shielding plate 80
A constant gap 78 is provided between the uppermost guide roller 74 pivotally supported by the guide bar 72 (see FIGS. 1 and 6B).

Below the bottom plate 70 of the cage 16, a ball screw 84 connected to a drive shaft of a motor 82 constituting the lifting means 17 is provided, and the first support member 86 is rotated by the rotation of the ball screw 84. The cage 16 can be moved in the vertical direction via the. The first support member 86
Are guided by a holding plate 89 fixed on the second support member 88. On the holding plate 89, guide plates 90 are provided on the front side and the back side of the document cassette feeder 10 in order to prevent the document cassette 14 loaded in the cage 16 from coming off in the vicinity of the cage 16. Are provided (see FIGS. 1 and 5). The vicinity of the cassette insertion opening 18 in the guide plate 90 and the image reading device 20
A part of the document cassette 14 is cut away in the vicinity of the communication port 36 to allow the document cassette 14 to be loaded and unloaded, and tapered portions 92 are formed above and below the document port 14 to prevent the document cassette 14 from being pinched.

A guide roller 94 and a cassette identifying means 96 are provided between the guide plate 90 and the communication port 36 communicating with the image reading device 20 (see FIG. 5).
The cassette identification means 96 is configured by arranging a plurality of light emitting elements and a plurality of light receiving elements so as to face each other with the insertion path of the original cassette 14 interposed therebetween, and is set in the cassette identification section 30 of the original cassette 14. The read data is read.

Next, the cassette carrying mechanism 21 is, as shown in FIG. 5, a drive plate 98 which is displaceable in the direction of arrow A or B.
And a motor 100 fixed to the drive plate 98. The drive plate 98 is supported by a pin 103 that engages with an elongated hole 102 defined in the drive plate 98,
It is displaced in the direction of arrow A or B under the action of an eccentric cam driven by a motor (not shown). The pulley 105 that engages with the drive shaft of the motor 100 is the belt 106.
Is connected to each roller 104 via. Each roller 104
Are conveying rollers 108a, 108b, 108c provided on the side surface side of the drive plate 98 via belts 107, 109.
Is linked to. In this case, the transport rollers 108a,
When the drive plate 98 is displaced in the direction of the arrow B, the reference numerals 108 b and 108 c denote the document cassettes 14 loaded in the cage 16.
Abut the side surface of.

Here, the sensor for detecting the original cassette will be described. Sensors 64a and 64b and sensors 66a and 66b for detecting the positions of the front end portion 62a and the rear end portion 62b with respect to the carrying-in direction (arrow X direction) of the document cassette 14 are arranged on both sides of the cage 16. (See FIG. 5). The sensors 64a and 64b and the sensors 66a and 66b include a pair of light emitting elements (for example, L
ED) and a light receiving element (for example, a phototransistor), facing the side surface of the document cassette 14 and arranged in two pairs in a direction orthogonal to the transport direction (arrow X direction). In addition, as shown in FIG.
The distance L1 from the front end 62a or rear end 62b of the document cassette 14 to the adjacent guide plate 90 is determined by the sensors 64a, 64 from the front end 62a or rear end 62b of the document cassette 14.
b or the distance L2 to the sensors 66a and 66b is set to be larger than the distance L2. That is, the respective separation distances are L1 ≧
By setting L2, for example, when the document cassette 14 loaded in the cage 16 is close to the guide plate 90, the sensors 64a, 64b and the sensor 66a arranged at the front end portion 62a or the rear end portion 62b. , 66b
One of the sensors 64a and 64b or the sensors 66a and 66b is in a non-detection state, and it can be detected in advance that the loaded document cassette 14 is in a state of protruding near the guide plate 90. Because you can.

Next, FIG. 7 shows a check circuit 63 for self-checking the sensors 64a and 64b and the sensors 66a and 66b. The check circuit 63 includes an oscillation control circuit 67 that outputs an oscillation control signal, and two pairs of sensors 64a and 64b and a sensor 66 based on the oscillation control signal.
Oscillation circuit 65 for supplying an oscillation pulse signal to the light emitting element side of a and 66b, and sensors 64a and 64b and sensor 66.
a signal amplification circuit 69 for amplifying a signal received by the light receiving element side of a, 66b, and sensors 64a, 64b and sensor 66a from the signal amplified by the signal amplification circuit 69 and the oscillation pulse signal from the oscillation circuit 65. 66
Basically, it is composed of a detection circuit 71 for detecting the operating state of b.

On the other hand, a detection member 111 extending along the displacement direction of the cage 16 is arranged between the top plate 68 and the bottom plate 70. As shown in FIGS. 8 and 9, the detection member 111 has a first portion in which concave portions and convex portions are alternately formed in the longitudinal direction.
The detection unit 112a and a portion of the upper end of the first detection unit 112a, which is provided in parallel with the projection, become a projection, and the first detection unit 1
The portion of the lower end of 12a, which is provided in parallel with the concave portion, becomes a convex portion,
It has the 2nd primary detecting element 112b which becomes a crevice between these convex parts. The concave and convex portions of the first detector 112a are detected by the photo interrupter 110a, and the concave and convex portions of the second detector 112b are detected by the photo interrupter 110b.
In this case, the convex portion of the first detection unit 112a and the second detection unit 11
By detecting the convex portion of 2b, it is possible to detect that the cage 16 is at the lower limit end position, and by detecting the concave portion of the first detecting portion 112a and the convex portion of the second detecting portion 112b, the cage 16 is at the upper limit. It is possible to detect that it is at the edge position. Then, the cage 1 is provided between the upper limit end position and the lower limit end position.
The position of each stage of 6 can be detected.

A document cassette feeding device 10 according to this embodiment.
The image reading device 20 to which the document cassette feeding device 10 is connected is basically configured as described above, and its operation will be described next.

First, before loading the document cassette 14 into the document cassette supply device 10, the power source of the document cassette supply device 10 is turned on. At that time, the document cassette supply device 10 is initialized, and the sensors 64a, 64b and the sensors 66a, 66b for detecting the position of the document cassette 14 loaded in the cage 16 are normally operated according to the flowchart shown in FIG. The operation is checked to see if it is functioning. This will be described below with reference to the flowchart.

First, the motor 82 is driven, and the cage 16 is lowered to the set lower limit end under the rotating action of the ball screw 84 connected to the drive shaft of the motor 82 (step S10a). In this case, between the sensors 64a and 64b,
And the sensor 66a, 66b, the top plate 6 of the cage 16
The light shielding plate 80 provided at the lower part of 8 enters. When the light emitting elements of the sensors 64a and 64b and the sensors 66a and 66b are driven in this state, the light from each light emitting element is blocked by the light shielding plate 80 and does not enter the opposing light receiving element, so that the sensor circuit operates normally. When operating, it is detected that the two pairs of sensors 64a and 64b and the sensors 66a and 66b are in the light blocking state (step S10b).

Then, the cage 16 is raised by a predetermined amount (for example, 10 mm) under the driving action of the motor 82 (step S10c). At that time, between the sensors 64a and 64b,
Since the gap 78 is located between the sensors 66a and 66b, when the sensor circuit is operating normally, the light emitted from the light emitting element is received by the light receiving element,
The non-light-shielded state is detected (step S10).
d, S10e).

Here, the sensors 64a, 64b and the sensor 6
A case will be described where 6a, 66b or a part of the sensor circuit for confirming the state based on the signals from 6a, 66b fails.

In this case, if the non-light-shielded state is detected in the light-shielded state, it can naturally be known that an abnormality has occurred somewhere in the sensor circuit. Further, in the non-light-shielded state, when the light-shielded state is detected, it can be at least known that the light-emitting element is not emitting light or the light-receiving element is out of order. If a sensor circuit including the light emitting element and the light receiving element fails,
Abnormality is displayed via a display unit (not shown) (step S10f). By using this function, it is possible to confirm whether or not the cage 16 is correctly moved to a predetermined position (in this case, the light blocking position by the light blocking plate 80 and the non-light blocking position in the gap 78).

As described above, the sensors 64a, 64b for detecting the position of the document cassette 14 by detecting the light blocking state and the non-light blocking state of the light emitted from the light emitting element.
It can be confirmed in advance that the sensors 66a and 66b are functioning normally. As described above, the document cassette supply device 10 is turned on and initialized, and the position detection is performed by the sensors 64a and 64b and the sensors 66a and 66.
The operation check of b can be performed simultaneously. The operation check of the sensors 64a and 64b and the sensors 66a and 66b is not limited to the above-mentioned initialization, but can be performed at any time as needed.

Next, the document cassette 14 holding the read document 26 as shown in FIG.
The case of inserting from the cassette insertion port 18 of 0 will be described.

Here, prior to loading the document cassette 14, the cage 16 is arranged near the guide roller 59 at a position where the document cassette 14 can be loaded in an empty state. At that time, it is determined whether or not the document cassette 14 is loaded in the step portion in the cage 16 by the sensors 64a, 64.
b, the sensors 66a and 66b are surely detected.
The operation at this time will be described with reference to FIG.

First, the document cassette 14 is set in the receiving state by setting an empty stage in which the document cassette 14 is to be loaded in the step portion near the guide roller 59 in the cage 16 (step S11a). Then, the sensor 64
It is possible to detect that there is no document cassette 14 in the detected portion and the empty state by detecting the light emitted from the light emitting element side sensors of a, 64b and the sensors 66a and 66b by the light receiving element side sensor. it can.

That is, the oscillation control signal from the oscillation control circuit 67 is input to the oscillation circuit 65, and the oscillation pulse signal from the oscillation circuit 65 is input to the sensors 64a, 64b and the sensor 66.
It is supplied to the sensor on the light emitting element side of a and 66b, and the sensor is turned on when the oscillation pulse signal is turned on (step S11b). Then, in the non-light-shielded state, the light emitted from the light emitting element is received by the sensor on the light receiving element side (step S11c), and the signal obtained by the light receiving element, for example, the signal to be turned off is sent to the signal amplification circuit 69. After that, it is introduced into the detection circuit 71.

Next, the sensor on the light emitting element side of the sensors 64a and 64b and the sensors 66a and 66b is turned off to turn off the light emitting element (step S11d). The light receiving element detects the off state of the light emitting element (step S11).
e) For example, a signal that turns on is introduced into the detection circuit 71 via the signal amplification circuit 69.

In the detection circuit 71, when the oscillation pulse signal from the oscillation circuit 65 and the signal from the signal amplification circuit 69 obtained as described above have the relationship shown in FIG. 12, that is, the oscillation circuit 65. Signal of the signal amplification circuit 69 is turned off when the oscillation pulse signal of is on, and the signal of the signal amplification circuit 69 is turned off when the oscillation pulse signal of the oscillation circuit 65 is turned off.
When the signal of is turned on, the sensors 64a, 64b,
It is possible to confirm that the sensors 66a and 66b are functioning normally, and at the same time, it is possible to confirm that the document cassette is not loaded in the stepped portion and is in the empty stage portion (step. S11f). On the other hand, when the output signal does not have the relationship shown in FIG. 12, the document cassette 14 is present on the stepped portion, or the light emitting element side sensor or the light receiving element side sensor of the sensors 64a and 64b and the sensors 66a and 66b, or these sensors. Both are defective, or the sensors 64a and 64b and the sensors 66a and 66b are
It is possible to detect in advance that there is a failure in a part of the sensor circuit including, and display an abnormality through a display unit (not shown) (step S11g). Specifically, for example, when there is an abnormality on the light receiving element side, when the oscillation pulse signal from the oscillation circuit 65 changes from the ON signal to the OFF signal, the signal from the signal amplification circuit 69 remains the ON signal. ,
Alternatively, the off signal remains as it is, and the abnormality on the light emitting element side is the case where the oscillation pulse signal from the oscillation circuit 65 is only one of the on signal and the off signal. When both the light receiving elements are abnormal, the signal amplification circuit 6 is used when the oscillation pulse signals from the oscillation circuit 65 are only ON signals or OFF signals, respectively.
9 is a case where only an ON signal or an OFF signal is provided, respectively. In this way, the sensor circuit can be self-checked.

When it is confirmed by the self-check of the sensor circuit that the sensor circuit is functioning normally and the document cassette 14 is not loaded in the empty space, the document cassette feeding device 10 Document cassette 14
Is detected by a sensor 58 provided at one end of the cassette insertion table 56, and the cassette transport mechanism 21 is driven. The document cassette 14 detected by the sensor 58 is guided by the guide roller 59,
It is loaded into the cage 16. That is, the document cassette 14 inserted from the cassette insertion port 18 is held by the outer peripheral surface of the guide roller 59 engaging with the v-shaped groove portions 28 a and 28 b on the side surface of the document cassette 14 and conveyed into the cage 16. To be done. Then, when the document cassette 14 is carried into a predetermined position in the cage 16, the sensor 58
It is conveyed to the cassette conveyance mechanism 21 driven by being detected by. That is, the eccentric cam rotates under the driving action of a motor (not shown), and the driving plate 98 is displaced in the arrow B direction by the action of the eccentric cam. At that time, the conveying roller 108 provided on the side surface side of the drive plate 98.
a and 108b are groove portions 28a and 28b of the document cassette 14.
Engage with. Then, the motor 100 fixed to the drive plate 98 is driven, and the roller 104 is rotated under the driving action of the motor 100, and the belt 104 is attached to the roller 104.
Transport rollers 108a, 1 connected via 7, 109
08b and 108c rotate. The transport roller 108
With the rotation of a, 108b, and 108c, the document cassette 1
The tip portion 62a of No. 4 is inserted between the light emitting element and the light receiving element forming the cassette identifying means 96.

In this case, the front end portion 62 of the document cassette 14 is
At a, a cassette identification unit 30 is provided which sets the type of the original cassette 14 and the identification symbol of the read original 26 held in the original cassette 14 by a plurality of light transmitting units and a plurality of light shielding units. Therefore, the document cassette feeder 10 receives the light output from the light emitting element by the light receiving element through the cassette identification section 30 to read and record the information of the document cassette 14 loaded in this step. can do.

When the information from the original cassette 14 is read, the original cassette 14 is returned to a predetermined portion of the step under the driving action of the cassette transport mechanism 21, and then the drive plate 98 is moved under the action of the eccentric cam. It is displaced in the direction of arrow A and retracted from the cage 16.

Here, whether or not the document cassette 14 is located at a predetermined portion of the stepped portion is determined by two pairs of sensors 64a and 64b and sensors 66a and 66b arranged on the side surface of the document cassette 14. To be detected. That is, the light emitted from the light emitting elements of the sensors 64a and 64b is blocked by the front end portion 62a of the original cassette 14, the light receiving element detects the light blocking state, and the light emitted from the light emitting elements of the sensors 66a and 66b is emitted from the original cassette. 14 rear end portion 62b
It is possible to detect that the document cassette 14 is at a predetermined position by blocking the light and detecting the light blocking state.

After the sensors 64a and 64b and the sensors 66a and 66b detect that the document cassette 14 has been loaded into a predetermined portion of the cage 16, another document cassette 14 is placed on another vacant step. The cage 16 is moved up and down under the rotational drive of the motor 82 in order to load.
In this case, the document cassette 14 stored in the cage 16
The distance L1 from the front end portion 62a or the rear end portion 62b of the document cassette 14 to the guide plate 90 standing upright is determined from the front end portion 62a or the rear end portion 62b of the document cassette 14 to the sensors 64a, 6
4b or the separation distance L2 to the sensors 66a and 66b
It is getting bigger. As a result, the sensors 64a, 64
By detecting the positions of both ends of the document cassette 14 by b and the sensors 66a and 66b, the cage 16 can be moved up and down to a predetermined portion without the document cassette 14 being sandwiched by the guide plate 90.

In this way, by repeating the same operation as described above, it becomes possible to load a plurality of original cassettes 14 into the cage 16. Subsequently, when the document cassette 14 loaded in the cage 16 is supplied into the image reading apparatus 20, the ball screw 84 is driven by the driving action of the motor 82.
And the cage 16 is moved up and down to rotate the image reading device 2
The stepped portion in which the document cassette 14 to be supplied into 0 is loaded is stopped at a position corresponding to the communication port 36. Therefore, by operating the cassette carrying mechanism 21, the original cassette 14 is fed into the image reading device 20 through the communication port 36 under the driving action of the cassette feeding mechanism 21.

The image reading device 20 detects the document cassette 14 by the insertion detecting means 38 to convey the paper 42.
Is driven to convey the document cassette 14 to the image reading section 44. In this case, the cassette identification means 40 performs the work of reading the information of the document cassette 14. Subsequently, in the image reading unit 44, the light output from the light source 48 is received by the light receiving element via the read document 26 held in the document cassette 14, and the image is read.

Although the original cassette supply device 10 can automatically supply the original cassette 14 to the image reading device 20, if a failure such as machine down occurs, the original cassette 14 is inserted from the cassette insertion port 18. The original cassette 14 cannot be supplied. To deal with such a situation, in the present embodiment, as shown in FIG. 2, when the first lid portion 52 at the upper part of the document cassette feeding device 10 is removed, the energization of the cage raising / lowering motor 82 is cut off and the manual operation is stopped. By releasing the brake, the cage 16 can be pushed down to a predetermined position by hand, the document cassette 14 can be loaded between the guide portions 76 on the top plate 68, and can be manually supplied to the image reading device 20.

[0047]

According to the document cassette feeding device having the sensor circuit self-checking mechanism according to the present invention, the following effects can be obtained.

That is, a sensor arranged at the side of the cage, which is composed of at least a pair of light emitting element and light receiving element, blinks, and the blinking state is detected, so that the state in which there is no document cassette in a pseudo manner and the state in which there is a document cassette are simulated. Detect.
Thus, by detecting the blinking state, it is possible to self-check whether the sensor circuit including the sensor is operating normally.

Further, according to the present invention, at the same time as the self-check of the sensor circuit, when the original cassette is inserted, it can be surely detected that the loading portion of the original cassette is in an empty state, so that the original cassettes are not in contact with each other. There is an advantage that a collision can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional configuration diagram of a document cassette feeding device according to an embodiment of the present invention.

FIG. 2 is a perspective view of the original cassette feeding device according to the exemplary embodiment of the present invention in a state in which a lid portion is opened.

FIG. 3 is a perspective view of a document cassette loaded in the document cassette supply device shown in FIG.

FIG. 4 is a schematic configuration diagram of the document cassette supply device and the image reading device connected thereto shown in FIG.

5 is a partial cross-sectional plan view of the document cassette supply device shown in FIG.

6A is a plan view showing a positional relationship between a guide plate, a document cassette, and a sensor, and FIG.
FIG. 7 is a side view of FIG. 6 (a).

FIG. 7 is a circuit diagram of a check circuit for self-checking a sensor circuit.

8 is a perspective explanatory view of a detection member that detects upper and lower limit positions of a cage that houses a document cassette and moves up and down in the document cassette supply device shown in FIG. 1. FIG.

9 is a side view showing a first detection unit and a second detection unit of the detection member shown in FIG.

FIG. 10 is a flowchart for checking the operation of the sensor circuit.

FIG. 11 is a flow chart in the case of self-checking a sensor circuit.

12 is a time chart of the check circuit shown in FIG.

[Explanation of symbols]

 Reference numeral 10 ... Original cassette feeding device 14 ... Original cassette 16 ... Cage 20 ... Image reading device 21 ... Cassette transport mechanism 63 ... Check circuit 64a, 64b, 66a, 66b ... Sensor 65 ... Oscillation circuit 67 ... Oscillation control circuit 69 ... Signal amplification circuit 71 ... Detection circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Shiraishi 798, Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Fuji Photo Film Co., Ltd.

Claims (1)

[Claims] 1. A document cassette feeding device for selectively feeding a plurality of document cassettes holding a document to be read to an image reading device, the document cassette feeding device having a plurality of steps for loading the document cassettes in a predetermined direction. A sensor which is disposed on a side portion of a movable cage and includes at least a pair of a light emitting element and a light receiving element which are arranged to face the step portion, and which detects a document cassette loaded in the step portion; And a detection circuit for detecting a lighting state and a non-lighting state of the light emitting element based on a signal from the light emitting element which constitutes the sensor. A document cassette feeding device having a self-checking mechanism of a sensor circuit.