JP3166101B2 - Automatic document feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder provided in a document processor such as an electrostatic copying machine or an image reader.

[0002]

2. Description of the Related Art In recent years, copiers have come to use an automatic document feeder which automatically and automatically supplies a plurality of documents to a document set position on the upper surface of a transparent plate with the speeding up and automation of copying processing. I have. An automatic document feeder for automatically feeding a plurality of documents sequentially to a document processor such as a facsimile or an image reader has been widely and practically used. This type of automatic document feeder includes document placing means for placing a document, and document carrying means for sequentially feeding the lowermost document placed on the document placing means. In such an automatic document feeder, in order to handle documents of various sizes, it is necessary to configure the document placing means so as to be able to store a document of the maximum size usable by the device. However, providing a document table capable of storing a usable maximum size document requires a large space, which causes a problem that the entire apparatus becomes large. In order to solve such a problem, the document placing means is constituted by a document table and an auxiliary table rotatably mounted at an upstream end of the document table. For example, Japanese Utility Model Publication No. 3-55557 discloses an auxiliary table which is folded on a table to rotate the auxiliary table behind the original table to extend the table when a large original is used.

[0003]

Thus, the document placing means constituted by the document table and the auxiliary table disclosed in the above publication improves the weight drop of the document when a large document is placed. Therefore, the auxiliary table is configured to be supported at an inclination angle larger than the document table mounting angle. For this reason, the original placing surfaces of the original table and the auxiliary table form a letter-shaped shape. Therefore, the original placed over the original table and the auxiliary table is It is bent along the surface. When the document is bent in this manner, a large frictional force acts between the documents at the bent portion. For this reason, in the case of a document having a large friction coefficient, a paper feed failure may occur.

The present invention has been made on the basis of the above-mentioned fact, and a main technical problem thereof is that an original table configured to support an auxiliary table at an upstream end of the original table with an inclination angle larger than the original table mounting angle. Even if the placing means is used, the placed document does not bend along the document placing surfaces of the two tables, and it is possible to prevent a feeding failure caused by the document being bent beforehand. An object of the present invention is to provide a document conveying device.

[0005]

According to the present invention, in order to achieve the above technical object, a document placing means for placing a document and a lowermost document placed on the document placing means are provided. And a document carrying means for sequentially feeding documents from the original document carrying means, the document placing means is rotatable to a document table connected to the document carrying means and an upstream end of the document table. A first position mounted and folded on the original table, and an auxiliary table pivoted upstream of the original table and positioned at a second position supported at an inclination angle larger than the mounting angle of the original table; And an upstream end of the original table is provided with a support member that protrudes above the original mounting surface and supports the mounted original.

[0006]

In the automatic document feeder constructed according to the present invention, the auxiliary table is folded on the original table and used at the first position when the original is small, and the auxiliary table is used when the original is large. It is rotated to the upstream side of the document table and used at the second position. When a document is placed on the document table and the auxiliary table while the auxiliary table is positioned at the second position,
A front portion of the document in the transport direction is placed along the document placement surface of the document table, a rear end in the transport direction is supported by the auxiliary table, and an intermediate portion thereof is supported by the support member. Therefore, even if the auxiliary table is configured to have an inclination angle α larger than the mounting angle of the original table, the original placed over the original table and the auxiliary table is supported at the intermediate portion by the support member, It does not bend.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of an automatic document feeder constructed according to the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an upper end portion of an electrostatic copying machine 2 and an automatic document feeder 4 mounted thereon. The electrostatic copying machine 2 has a housing 6, and on the upper surface of the housing 6, a transparent plate 8 (FIG. 2), which may be a glass plate, is provided. On one side (left side in FIG. 2) of the transparent plate 8, a document regulating member 1 for defining a document set reference position G is provided.
0 is disposed, and a stationary mounting member 12 is disposed on the other side (the right side in FIG. 2). The automatic document feeder 4 configured in accordance with the present invention includes a housing 6 of the electrostatic copying machine 2.
1 is pivotally mounted between a closed position indicated by a solid line in FIG. 1 and an open position indicated by a two-dot chain line around a pivot axis extending along the rear edge of the transparent plate 8. Electrostatic copier 2
When the original is manually placed on the transparent plate 8, the automatic document feeder 4 is opened to expose the transparent plate 8, the original is placed at a required position on the transparent plate 8, and With the document feeder 4 closed, the transparent plate 8 and the document placed thereon are covered. When placing a document on the transparent plate 8, the document is placed in a desired position by contacting one edge of the document with the leading edge of the document regulating member 10 and positioning the one edge of the document at the document setting reference position G. Position. When the document is automatically loaded onto the transparent plate 8 using the automatic document feeder 4 and is automatically output from the transparent plate 8, the automatic document feeder 4 is positioned at the closed position.

Continuing the description with reference to FIG. 1, the illustrated automatic document feeder 4 includes a front cover 14 and a rear cover that are disposed at an interval in the front-rear direction (the direction perpendicular to the plane of FIG. 2). 16 is included. The front cover 14 and the rear cover 16 can be formed from an appropriate synthetic resin. A rear support substrate (not shown) is provided in the rear cover 16, and such a rear support substrate is connected via a mounting mechanism (not shown) which may itself be a known form. Thus, it is mounted on the upper surface of the housing 6 of the electrostatic copying machine 2 so as to be pivotable. Various components of the automatic document feeder 4 are directly or indirectly supported by the rear support substrate. A document placing means 18 and a document discharge tray 20 are provided between the front cover 14 and the rear cover 16.

The document placing means 18 will be described with reference to FIGS. The document placement means 18 includes a document table 22 that extends upward from the downstream end on the left side to the upstream end on the right side at a predetermined angle (placement angle) in FIG. 2, and an upstream end of the document table 22. And an auxiliary table 24 which is rotatably mounted on the auxiliary table 24. A pair of width regulating members 26 are mounted on the document table 22 so as to be movable in the width direction. The pair of width regulating members 26, 26 are connected to each other below the document table 22 via a well-known rack and a pinion mechanism (not shown). They are moved in the direction of approach and in the direction of separation from each other. The document table 22 is formed of a synthetic resin, and has two upstream supporting members 22 protruding above the document placing surface 221 and supporting the placed document.
2, 222 are integrally formed at predetermined intervals.
In the illustrated embodiment, two protruding support members 222 are illustrated as the support members, but three or more support members may be provided, and one support member that is long in the width direction. It may be. The auxiliary table 24 is integrally formed of a synthetic resin, and has support legs 241 and 241 on both sides, and columnar pins 242 and 242 are provided on inner surfaces of lower ends of the support legs 241 and 241 facing each other. . Lower ends of the support legs 241, 241 are formed in concave portions 223, 223 formed at the rear end of the original table 22.
The auxiliary table 24 is inserted into the support holes 224, 224 provided in the walls forming the recesses 223, 223, so that the auxiliary table 24 is
242 is rotatably supported. The auxiliary table 24 rotatably supported in this manner is located at the first position where it is folded on the document table 22 as shown in FIG. 2 and at the upstream side of the document table 22 as shown in FIGS. The document table 22 is rotated and is positioned at the second position supported at an inclination angle α larger than the mounting angle of the document table 22. In order to hold the auxiliary table 24 in the second position, stopper portions 24 are provided at the lower ends of the support legs 241 and 241 respectively.
3 and 243 are provided, and the auxiliary table 24 is
Stopper portions 243, 24 when positioned at
3 is a locking portion 22 provided at the upstream end of the document table 22
5 and 225, the clockwise rotation from the second position shown in FIG. 3 is further restricted. The document placing means 18 configured as described above uses the auxiliary table 24 in the first position shown in FIG. 2 when small documents such as A4 and B5 are used, and uses the document such as A3 and B4. When the size is large as described above, the auxiliary table 24 is used while being positioned at the second position shown in FIGS. When a document is placed on the document table 22 and the auxiliary table 24 in a state where the auxiliary table 24 is positioned at the second position, as shown in FIG. 221, the rear end in the transport direction is supported by the auxiliary table 24, and the intermediate portion is supported by the support members 222, 222. Therefore, even if the auxiliary table 24 is configured to have an inclination angle α larger than the mounting angle of the document table 22,
The document placed over the auxiliary table 24 does not bend because the middle portion thereof is supported by the support members 222, 222.

The document discharge tray 20 is disposed below the document placement means 18 and has a document placement surface 28 formed in a mountain shape when viewed from the front-back direction (the direction perpendicular to the sheet of FIG. 2).
Are formed. A left end cover 30 is provided between the left ends of the front cover 14 and the rear cover 16, and a right end cover 32 is provided between the right ends. In addition,
Inside the front cover 14, a safety switch SW1 for detecting the open / close state of the automatic document feeder 4 and a left end cover 3
0, and a safety switch SW for detecting the open / closed state of the right end cover 32.
The switches are arranged in series, and when the covers are located at the closed position and all the switches are closed, an ON signal is output to the control means described later.

Continuing the description with reference to FIGS.
On the downstream side of the document table 22, there is provided a document carrying means 33 having a forward feeding means 38 and a document separating mechanism 60. The document loading means 33 includes a lower guide plate 34 extending downstream of the document table 22 and an upper guide plate 36 disposed above the lower guide plate 34 at a predetermined interval. . The upper guide plate 36 is disposed downstream from the downstream end of the forward feed means 38 in the transport direction. A forward feed roller 40 constituting forward feed means 38 is disposed below the lower guide plate 34, and the forward feed roller 40 is provided with an opening 4 formed upstream of the lower guide plate 34.
2 and projecting slightly upward. Above the forward feed roller 40, a forward feed pressing means 44 constituting the forward feed means 38 is provided. The forward feed pressurizing means 44
A rotating shaft 46 disposed above the forward feed roller 40 in parallel with the forward feed roller 40; and an upper end fixed to the rotating shaft 46 and a lower end placed on the document table 22. And a pressing plate 48 acting on the original 50 inserted on the lower guide plate 34. The pressing plate 48 is formed of an elastic thin plate made of a stainless steel plate in the illustrated embodiment, and the upper end thereof is fixed to the rotating shaft 46 by a fixing means such as a screw. It is configured to act on the upper surface of the uppermost document 50 placed on the document table 22 at a position higher than the feed roller 40 to press the document 50 against the forward feed roller 40. The rotating shaft 46 that constitutes the forward feed pressing means 44 is connected to a side plate 51 a (see FIG. 4, a rear side plate 51) provided at the front and rear ends of a support substrate 51 disposed above the forward feed roller 40.
(only a is shown).
The rotating shaft 46 is connected to a solenoid SL1 via a link mechanism 52. When the solenoid SL1 is urged, the rotating shaft 46 is rotated in a direction shown by an arrow 56 against the spring force of a return spring 54. When the solenoid SL1 is deenergized, the solenoid SL1 is rotated in the direction shown by the arrow 58 by the spring force of the return spring 54. Accordingly, the pressing plate 48 attached to the rotating shaft 46 presses the document 50 inserted on the stationary plate 34 when the solenoid SL1 is urged and the rotating shaft 46 is rotated in the direction shown by the arrow 56. The solenoid SL1 is deenergized, and the rotating shaft 46 is moved by the spring force of the return spring 54 as indicated by an arrow 5 in FIG.
When it is turned in the direction shown in FIG. A document set switch SW4 as document detection means is provided on the support substrate 51.
The document set switch SW4 is connected to the document table 22.
When the original 50 is placed on the lower guide plate 34 and the original 50 is inserted, the ON signal as a first signal is used as the first signal. When the original 50 is not placed on the original table 22, the ON signal is used as a second signal. Is output to the control means described later.

The document separating means 60 disposed downstream of the forward feed means 38 projects upward through an opening 62 formed in the stationary guide plate 34 below the lower guide plate 34. A paper feed roller 64 having a plurality of rollers, the upper guide plate 36, and the upper guide plate 36
And a separation belt mechanism 66 protruding downward through an opening 77 formed at the bottom. At the upstream end (the right end in FIG. 4) of the upper guide plate 36, there is formed an inclined portion 361 that extends slightly upstream from a right angle. A document regulating plate 59 is mounted on the rear surface of the inclined portion 361 at a position facing the pressure plate 48 by a fixing means such as an adhesive. This document regulating plate 59
Is formed so that its lower end protrudes below the lower surface of the upper guide plate 36. Therefore, the document regulating plate 59 regulates that most of the document 50 placed on the document table 22 and inserted on the lower guide plate 34 moves to the document separating mechanism 60 side, Only one or several lower sheets are allowed to move to the separation belt mechanism 66 side. The separation belt mechanism 66 is disposed above the upper guide plate 36, and includes a driving roller 67, a driven roller 68,
A plurality of separation belts 69 wound around a driving roller 67 and a driven roller 68 and alternately disposed with the plurality of paper supply rollers 64, and each separation belt 69 is formed on the upper guide plate 36. It is projected downward through the opening 74 formed. The feed roller 40 and the feed roller 6
4 and the separation belt mechanism 66 are driven to rotate in directions indicated by arrows 79, 80 and 82, respectively, by a driving means 78 including an electric motor M1 and a transmission mechanism 76 such as a gear mechanism or an electric belt mechanism. The electric motor M1 has a rotation amount detecting means FG1 such as a rotary encoder or a frequency generator which constitutes a document conveying amount detecting means.
And outputs a pulse signal, which is a detection signal, to control means described later. The document separating means 60 configured as described above prevents two or more documents from being fed from the document layer placed on the document table 22, and only the lowermost document is loaded into a document loading unit to be described later. The paper is fed to the road 98.

A document 50 placed on the document table 22 and inserted on the lower stationary guide plate 34 as shown in FIG. 4 and FIG. A document stopper 84 operable between an operation position for restricting insertion of the document separation mechanism 60 into the document separation mechanism 60 and a retracting position allowing movement toward the document separation mechanism 60 is disposed. The document stopper 84 is disposed below the lower guide plate 34, and its base end is arranged at a position upstream of the forward feed roller 40 in parallel with the axis of the forward feed roller 40 with a space therebetween. The lower guide plate 3
4 is arranged through the opening formed therein. The rotation shaft 86 to which the document stopper 84 is attached is operated by stopper driving means 87. The stopper driving means 87 includes a latch type solenoid SL2, and a link mechanism 88 connecting the plunger 90 of the latch type solenoid SL2 and the rotation shaft 86. The latch type solenoid SL2 may be a well-known type, and includes a permanent magnet, a suction coil and a separation coil therein. When the suction coil is energized, the plunger 90 is attracted, and in this state, the plunger is attracted by the magnetic force of the permanent magnet. Even if the suction coil is de-energized by sucking the 90, the plunger 90 is held in the suction state. When the plunger 90 is separated from the attracted state, the separated coil is biased to separate the plunger 90 against the magnetic force of the permanent magnet, and then the plunger 90 is maintained in the separated state even when the separated coil is deenergized. It is supposed to be.
Accordingly, when the plunger 90 is sucked by urging the suction coil of the latch type solenoid SL2, the rotating shaft 86 moves to the direction indicated by the arrow 9.
The document stopper 84 is rotated in the direction shown in FIG. 2 and attached to the rotating shaft 86, and is positioned at the retreat position shown by a solid line in FIG. Also, the latch type solenoid SL2
When the plunger 90 is separated by urging the separation coil of
The rotation shaft 86 is rotated in the direction indicated by the arrow 94, and the original stopper 84 attached to the rotation shaft 86 is positioned at the operation position shown by the two-dot chain line in FIG.
6 is held by the spring force. The original stopper 8
4, a shield plate 85 is attached, and on the other hand, a stopper position detecting means SW5 is provided at a position facing the original stopper 84 when the original stopper 84 is located at the retreat position shown by a solid line. The stopper position detecting means SW5 includes a light emitting element and a light receiving element. When the document stopper 84 is positioned at the operation position indicated by the two-dot chain line, an ON signal as the first signal is received, and the document stopper 84 is retracted indicated by the solid line. When the shielding plate 85 is positioned between the light emitting element and the light receiving element, the OFF signal as the second signal is output to the control means described later.

Continuing the description with reference to FIGS. 2 and 6, below the original placing means 18, a transport belt mechanism 100 is provided.
Are arranged. The transport belt mechanism 100 that constitutes the transport unit includes a driving roller 102 and a driven roller 10 that are disposed at intervals in the transport direction (the left-right direction in FIG. 2).
4, an endless belt 106 wound around them, and rolling rollers 105a, 105b, 105c, 105d disposed between the driving roller 102 and the driven roller 104.
105e. The lower running portion of the endless belt 106 extends along the transparent plate 8 of the electrostatic copying machine 2, and a document conveying path 108 is defined between the two. A document carrying path 98 is formed between the document carrying path 108 and the document separating unit 60. The document carrying path 98 is defined between the inner guide plate 110 and the outer guide plate 112. A registration roller pair 114 is provided in the document carrying path 98. The registration roller pair 114
Is composed of a driving roller 116 and a driven roller 118. A reflection-type optical original detector SW6 including a light emitting element and a light receiving element is disposed upstream of the registration roller pair 114 in the original introduction path 98, and the original detector SW6 is connected to the original introduction path 98. The passing document 50 is detected, and a detection signal is sent to a control unit described later. The drive roller 102 of the transport belt mechanism 100 and the drive roller 116 of the registration roller pair 114 are driven to rotate by a drive unit 120 including a forward / reverse rotation electric motor M2 and a transmission mechanism 118 such as a gear mechanism or a belt mechanism. . The driving roller 116 of the registration roller pair 114 is connected to the transmission mechanism 118 and the electromagnetic clutch C.
They are connected via L1. The electric motor M
A rotation amount detection means FG2 such as a rotary encoder or a frequency generator constituting the document conveyance amount detection means is attached to 2, and outputs a pulse signal as a detection signal to a control means described later.

A document reversing / discharging means 128 is provided on the right side of the document conveying path 108. The document reversing / discharging means 128 has a first document discharging path 130, and the first document discharging path 130 is provided between the reversing roller 134 and the outer guide plates 136, 138 constituting the document reversing and conveying means. Stipulated. Note that three driven rollers 135a, 135b, and 135c are disposed on the outer periphery of the reversing roller 134 in a pressed state. The first document discharge path 130
Downstream of the second document discharge path 140 and the document reversal path 1
42 is provided in a branched manner, and a branch control plate 144 is provided in this branched portion. Second document output path 140
Is defined between the branch control plate 144 and the outer guide plate 146. At the downstream end of the second document discharge path 140,
A discharge roller pair 152 including a driving roller 148 and a driven roller 150 is provided. A reflection type optical document detector SW7 including a light emitting element and a light receiving element is disposed in the second document discharge path 140.
Detects the document 50 passing through the second document discharge path 140 and sends a detection signal to a control unit described later. The reversing path 142 includes a reversing roller 134 and a branch control plate 144.
And the outer guide plate 154, the downstream end of which is formed facing the downstream end of the document conveying path 108. The document reversing path 142 is provided with a reflective optical document detector SW8 including a light emitting element and a light receiving element, and the detector SW8 detects the document 50 passing through the document reversing path 142, The detection signal is sent to control means described later. The branch control plate 144 has a shaft 15
6 and is operated by a solenoid SL3. When the solenoid SL3 is deenergized, the solenoid SL3 is positioned at a position shown by a solid line in FIG.
Is biased, it is positioned at a position shown by a two-dot chain line in FIG. 2 against the spring force of the return spring 158. Therefore, the document conveyed through the first document discharge path 130 is sent to the second document discharge path 140 when the solenoid SL3 is deenergized, and is transmitted to the document reversal path when the solenoid SL3 is biased. 142. The reversing roller 134 and the discharge roller pair 152
Are driven by driving means 162 comprising an electric motor M3 and a transmission mechanism 160 such as a gear mechanism or an electric belt mechanism, as indicated by arrows 164 and 166, respectively.
Is rotated in the direction indicated by. The electric motor M3 has a rotation amount detecting means FG such as a rotary encoder or a frequency generator which constitutes a document conveying amount detecting means.
3 is attached, and outputs a pulse signal as a detection signal to control means described later.

The automatic document feeder includes a control unit 2 shown in FIG.
00 is provided. The control means 200 is configured by a microcomputer, and includes a central processing unit (CPU) 201 for performing arithmetic processing according to a control program, a read-on memory (ROM) 202 for storing a control program and a control map, and storing arithmetic results and the like. A read / write random access memory (RAM) 203, a timer 204, an input interface 205 and an output interface 206 are provided. The input interface 205 of the control means 200 thus configured includes the safety switches SW1, SW1, SW3, the document set switch SW4, the stopper position detection means SW5, the reflection type optical detectors SW6, SW7, SW8, and the rotation amount. A detection signal is input from detection means FG1, FG2, FG3, etc., and the electric motor M
1, control signals are output to M2, M3, solenoids SL1, SL3, latch type solenoid SL2, and electromagnetic clutch CL1. The control means 200 is connected to the control means 210 of the electrostatic copying machine 2, and exchanges control signals between the two. An operation unit 220 and a display unit 230 are connected to the control unit 210 of the electrostatic copying machine 2. The operation means 220 is arranged on the front upper surface of the electrostatic copying machine 2 as shown in FIG. 1, and includes copy operation keys such as a copy start key, a copy number designation key, a duplex copy designation key, and a copy operation stop key. And the electrostatic copying machine 2
Copy information is input to the control means 210 of FIG. Display means 23
Numeral 0 is arranged on the front upper surface of the electrostatic copying machine 2 adjacent to the operation unit 220 like the operation unit 220, and displays copy information, failure information, and the like.

The automatic document feeder according to the illustrated embodiment is configured as described above, and its operation procedure will be described below with reference to flowcharts shown in FIGS.
8 to 10 show a main routine, FIG. 11 shows a subroutine for primary paper feeding, FIG. 12 shows a subroutine for secondary paper feeding,
FIG. 13 shows a subroutine for reverse sheet feeding.

In the main routine shown in FIGS. 8 to 10, the control means 200 first checks in step S1 whether all of the safety switches SW1, SW2 and SW3 are ON. That is, the automatic document feeder 4, the left end cover 30, and the right end cover 32
It is dangerous to operate the automatic document feeder 4 in a state where the document is opened, and if any one of them is opened, it is a check to prohibit the operation of the automatic document feeder 4. Therefore, in step S1, the safety switch SW
1. If any one of the switches SW2 and SW3 is OFF, wait until the cover is positioned at the closed position. If all the switches are ON, proceed to Step S2, and if the document set switch SW4 is ON, Whether or not there is, that is, whether or not a document is placed on the document table 22 is checked. Original set switch SW4 is ON
If not, it is determined that the document is not placed on the document table 22, and the process returns to step S1. If the document set switch SW4 is turned on in step S2, it is determined that a document is placed on the document table 22, and the process proceeds to step S3.
A value of 0 checks whether or not a copy start signal has been sent from the control means 210 of the electrostatic copying machine 2. This copy start signal is sent from the control means 210 to the control means 200 when the operator inputs the copy start signal with the copy start key of the operation means 220. Therefore, if the copy start signal has not been sent, there is no need to copy, and the process returns to step S1. If the copy start signal has been sent in step S3, the process proceeds to step S4, and the control means 200 determines whether or not the stopper position detection means SW5 is ON, that is, the document stopper 84 is at the operation position indicated by the two-dot chain line in FIG. Check if it is positioned. This is because when the original 50 is placed on the original placing means 18 and inserted on the stationary plate 34 in a state where the original stopper 84 is not located at the operation position indicated by the two-dot chain line in FIG. It reaches the document separating mechanism 60 beyond the lower end of the document regulating plate 59,
The document stopper 84 is positioned at the operation position to check whether the document 50 is set at the predetermined insertion position because there is a possibility that the document is double fed. If the stopper position detecting means SW5 is not ON in step S4, the document 50 may reach the document separating mechanism 60 and may be double fed. Therefore, the control means 200 does not shift to the document loading operation and the control means 200 proceeds to step S5. A jam alarm is displayed on the display unit 230 via the control unit 210 of the electrostatic copying machine 2. As a result, it is possible to prevent a double feed of documents caused by placing the document 50 on the document table 18 and inserting it on the stationary plate 34 in a state where the document stopper 84 is not positioned at the operation position.

If the stopper position detecting means SW5 is ON in step S4, that is, if the document stopper 84 is positioned at the operation position, the control means 200 proceeds to step S6, in which the electric motor M2 is driven to rotate forward to convey. In addition to the operation of the belt mechanism 100, the electric motor M3 is driven to operate the reversing roller 134 and the discharge roller 148, and the operation of discharging any misplaced original on the transparent plate 8 is performed. Further, the control means 200 determines in step S6
Then, the latch type solenoid SL2 is turned on (the latch type solenoid energizes the suction coil when sucking the plunger, and energizes the separation coil when separating the plunger. However, in the following description, the plunger is used for convenience. Is turned on when suction is performed, and turned off when the plunger is separated.) That is, the latch type solenoid SL2
And the original stopper 84 is positioned at the retracted position indicated by the solid line in FIG. Thus, the electric motor M2, the electric motor M3 and the latch type solenoid S
While activating L2, the control means 200 sets the timer T to T1. The set time T1 is, for example, 100
msec. Next, the control means 200 checks whether or not the elapsed time T0 from when the timer T was set to T1 has reached the set time T1 (step S1).
7) If the elapsed time T0 has not reached the set time T1, the process proceeds to step S8, where the stopper position detecting means SW
It is confirmed whether or not 5 is OFF, that is, whether or not the document stopper 84 is positioned at the retreat position indicated by a solid line in FIG. In step S8, the stopper position detecting means S
If W5 does not turn OFF, the process returns to step S7, and checks until the elapsed time T0 reaches the set time T1. If the stopper position detection means SW5 does not turn OFF even after the set time T1, the control means 200 returns to step S7. The operation of the document carrying means 33 is prohibited, and the process proceeds to step S9, where the document stopper 8 is controlled via the control means 210 of the electrostatic copying machine 2.
4 is displayed on the display means 230 indicating that it is abnormal. From this abnormal display, the operator can know that the latch type solenoid SL2 or the link mechanism 88 constituting the stopper driving means 87 has failed. If the stopper position detecting means SW5 is turned off in step S8, the process proceeds to step S10 shown in FIG. 8 to clear the timer, and further proceeds to step P0 to execute a subroutine for primary sheet feeding.

Next, the subroutine for primary paper feeding shown in FIG. 11 will be described. In step P1, the control means 200 turns on and drives the electric motor M1 of the document carrying means, and also urges the solenoid SL1 to place the pressing plate 48 on the document placing means 18 and insert it on the lower guide plate 34. The document 50 is pressed on the upper surface of the formed document 50.
For this reason, when the electric motor M1 is driven to rotate the forward roller 40, the forward roller 40
The original 50 is sent out by a frictional conveyance force generated at a contact portion between the lowermost original 50 and the lowermost original 50. When the original is fed by the forward feed roller 40 and the original is large, such as A3 or B4, the auxiliary table 24 is positioned at the second position shown in FIGS. Although placed on the auxiliary table 24, as shown in FIG. 3, since the intermediate portion of the original is supported by the support members 222, 222, the auxiliary table 24 is
Even if it is configured to have an inclination angle α larger than the placement angle of 2, the document does not bend, so that it is possible to prevent a paper feeding failure caused by the document being bent. When the electric motor M1 is driven, the paper feed roller 64 and the drive roller 67 of the separation belt mechanism 66 that constitute the document separation mechanism 60 together with the forward feed roller 40 are driven to rotate, and are placed on the document table 22. The lowermost document in the document layer inserted on the lower guide plate 34 is fed to the document carrying path 98. When the document on the document table 22 has been fed to the document feed-in path 98 in this way, the control means 200 determines whether or not the detector SW6 has been turned ON, that is, the leading end of the document fed to the document feed-in path 98 is detected by the detector. Check whether or not SW6 has been reached (step P
2). If the detector SW6 is not turned on in step P2, the process waits. If the detector SW6 is turned on, the control means 200 sets the timer T to T2 (step P2).
3). The set time T2 is set to, for example, 25 msec. Next, the control means 200 checks whether or not the elapsed time T0 after setting the timer T to T2 has reached the set time T2 (step P4).
If the elapsed time T0 has reached the set time T2, the process proceeds to step P5, where the electric motor M1 and the solenoid SL1 are turned off to supply the original. Stop the paper operation.
The original fed to the original loading path 98 by the advance roller 40 and the original separating mechanism 60 by the primary paper feeding operation is transferred to the pair of registration rollers 11 whose front ends are inactive.
Thus, the sheet is brought into contact with the nip portion of No. 4 and the primary sheet feeding is completed.

Returning again to the main routine shown in FIG.
When the primary paper feeding is completed as described above, the control means 20
In step S0, the process proceeds to step Q0 to execute a secondary paper feed subroutine. The subroutine for secondary paper feeding will be described with reference to FIG. The control means 200 turns on and energizes the electromagnetic clutch CL1 attached to the drive roller 116 of the registration roller pair 114 in step Q1. Electromagnetic clutch C
When L1 is energized, since the electric motor M2 has already been driven to rotate forward, the driving roller 11 of the registration roller pair 114
6 is driven to rotate. Therefore, the document fed to the nip portion of the pair of registration rollers 114 in the primary paper feeding is conveyed to a document conveying path 108 extending along the transparent plate 8 of the electrostatic copying machine 2, and further, The sheet is conveyed on the transparent plate 8 from the left side (one end) to the right side (the other end) in FIG. 2 by the conveyance belt mechanism 100 constituting the conveyance means. Next, the control means 200 controls the detector SW6 provided in the document carrying path 98 in step Q2.
Is turned off, that is, whether the trailing edge of the document has passed the detector SW6. If the detector SW6 is not turned off, the process waits. If the detector SW6 is turned off, the trailing edge of the document is detected. It is determined that the signal has passed the switch SW6, and the process proceeds to step Q3, where it is determined whether or not a double-sided copy signal is sent from the control unit 210 of the electrostatic copying machine 2. This double-sided copy signal is input to the control unit 210 of the electrostatic copying machine 2 by the operator using the double-sided copy designation key of the operation unit 220, and the control unit 210 transmits the double-sided copy signal to the control unit 20 based on the input signal.
Sent to 0. If there is a double-sided copy signal in step Q3, the flow advances to step R0 to execute a reverse paper feed subroutine. The reversal sheet feeding subroutine will be described later. If there is no double-sided copy signal in step Q3, the flow advances to step Q4 to start counting the pulse signal PSB from the rotation amount detecting means FG2 mounted on the electric motor M2 of the transport belt mechanism 100. If the counting of the pulse signal PSB is started in step Q4, the process proceeds to step Q5, and the control means 200 checks whether or not the pulse signal PSB has reached the set pulse number PS1. This set pulse number PS1 is a pulse number corresponding to the rotation amount of the electric motor M2 corresponding to the document conveyance amount from the detector SW6 to the document set reference position G in FIG.
If the pulse signal PSB has not reached the set number of pulses PS1 in step Q5, the conveyance is continued after waiting. If the pulse signal PSB has reached the set number of pulses PS1, the trailing edge of the original reaches the original set reference position G. Then, the process proceeds to step Q6, in which the electric motor M2 is turned off to stop the operation of the transport belt mechanism 100. At the same time, the electromagnetic clutch CL1 is turned off, and the count of the pulse signal PSB from the rotation amount detection means FG2 is cleared. Next, in step Q7, the control means 200 starts counting the pulse signal PSB from the rotation amount detecting means FG2 again. This is because even if the electric motor M2 is turned off, the drive shaft of the electric motor M2 does not stop immediately but slightly rotates due to inertia. Therefore, the trailing end of the document is rotated by the inertia force and conveyed to the position overrunning the document set reference position G and moved forward, that is, to the right side of the document set reference position G in FIG. This is to detect the transport amount (overrun amount). In step Q7, the rotation amount detecting means FG
When the counting of the pulse signal PSB from the second motor 2 is started, the control means 200 determines whether or not the pulse signal PSB from the rotation angle detecting means FG2 has become zero (0), that is, whether or not the electric motor M2 has stopped reliably. (Step Q
8). If it is confirmed in step Q8 that the pulse signal PSB from the rotation amount detection means FG2 has become zero (0), the process proceeds to step Q9, and the control means 200 determines when the electric motor M2 has stopped reliably, that is, when the rotation amount detection Means FG
The random access memory (RAM) 20 uses the number of pulses PS2 from the rotation amount detecting means FG2 until the time when the pulse signal PSB from the second signal becomes zero (0) as an overrun amount.
And clears the count of the pulse signal PSB from the rotation amount detection means FG2. Next, in step Q10, the control means 200 drives the electric motor M2 in the reverse direction to reversely operate the transport belt mechanism 100, and the rotation amount detecting means FG2 attached to the electric motor M2.
Starts counting of the pulse signal PSB. If the counting of the pulse signal PSB from the rotation amount detecting means FG2 is started in step Q10, the process proceeds to step Q11, and the control means 200 determines whether or not the pulse signal PSB has reached the pulse number PS2 corresponding to the overrun amount. Check. In step Q11, the pulse signal PSB changes the pulse number PS2 corresponding to the overrun amount.
If the pulse signal PS does not reach
If B reaches the pulse number PS2 corresponding to the overrun amount, it is determined that the trailing end of the document has reached the document set reference position G, and the process proceeds to step Q12, where the electric motor M2
Is turned off to stop the operation of the transport belt mechanism 100.
The control means 200 is a control means 210 of the electrostatic copying machine 2.
, A print signal, that is, an exposure start preparation completion signal is output.

Next, the reverse sheet feeding operation will be described based on the reverse sheet feeding subroutine shown in FIG. Control means 20
In step R1, in step R1, the electric motor M3 is turned on to rotationally drive the reversing roller 134, and the solenoid SL3 for controlling the operation of the branch control plate 144 is turned on and energized. When the solenoid SL3 is energized, the branch control plate 1
Since the document 44 is positioned at a position indicated by a two-dot chain line in FIG. 2, the document conveyed by the conveyance belt mechanism 100 and the reversing roller 134 passes through the document conveyance path 108 formed on the transparent plate 8 to the left (one end) in FIG. ) To the right side (the other end), and further to the document reversing path 142 through the first document discharge path 130. When the electric motor M3 and the solenoid SL3 are operated to convey a document to the document reversing path 142 in this manner, the control means 200 causes the document detector S disposed in the reversing path 142 to operate.
W8 is ON or not, that is, the front end of the original is detected by the original detector S
It is checked whether or not W8 has been reached (step R2). If the document detector SW8 is not turned on, the process waits. If the document detector SW8 is turned on, the process proceeds to step R3, in which the electric motor M2 of the transport belt mechanism 100 is rotated in reverse. The rotation amount detecting means FG3 attached to the electric motor M3 for driving the conveyance belt mechanism 100 in the reverse direction and for driving the reversing roller 134.
The counting of the pulse signal PSC is started. If the counting of the pulse signal PSC from the rotation amount detecting means FG3 is started in step R3, the process proceeds to step R4, where the control means 200 determines that the pulse signal PSC is equal to the set pulse number P.
It is checked whether or not S3 (the first predetermined transport amount) has been reached. The set pulse number PS3 is determined by
Is set to the document conveyance amount (the number of pulses) by the reversing roller 134, which corresponds to the time from when the electric motor M2 is driven to rotate in the reverse direction until the rotation speed is stabilized. The document conveyed by the reversing roller 134 is introduced to the right side (the other end) of the document conveyance path 108 in FIG. 2 and is conveyed leftward (one end) by the conveyance belt mechanism 100. If the pulse signal PSC does not reach the set pulse number PS3 in step R4, the process waits until the pulse signal PS
If C reaches the set pulse number PS3, step R5
To start the positioning control of the electric motor M2 of the transport belt mechanism 100, and the pulse signal PS from the rotation amount detecting means FG2 mounted on the electric motor M2.
B count starts counting. The positioning control means that when the front end of the document conveyed by the conveyance belt mechanism 100 approaches the document set reference position G in FIG. 2, the rotation speed of the electric motor M2 is reduced and the pulse signal PSB is set to the set pulse number PS4 (second When the electric motor M2 is turned off after reaching the predetermined conveyance amount, control is performed so that the original does not overrun the original set reference position G due to the inertial force. If the pulse signal PSB has begun to be counted, the process proceeds to step R6, where the control means 200 determines that the pulse signal PSB has reached the set pulse number PS4 (second pulse).
(The predetermined transport amount) is checked. The set number of pulses PS4 is the number of pulses corresponding to the document transport amount for transporting the front end of the document sent to the transport belt mechanism 100 to the document set reference position G by the transport belt mechanism 100 at the start of the counting of the pulse signal PSB. It is. If the pulse signal PSB does not reach the set pulse number PS4 in step R6, the conveyance is continued after waiting. If the pulse signal PSB reaches the set pulse number PS4, the front end of the document has reached the document set reference position G. Then, the process proceeds to step R7, in which the electric motor M2 is turned off to stop the operation of the transport belt mechanism 100. At the same time, the electric motor M3 is turned off to stop the operation of the reversing roller 134 and the discharge roller 148, and the solenoid SL3 is turned off to deenergize the branch control plate 144.
At the position indicated by the solid line. The control means 200 outputs a print signal, that is, an exposure start preparation completion signal, to the control means 210 of the electrostatic copying machine 2.

Next, returning to the main flow of FIG. 9, the description will be continued. If the primary paper feed subroutine P0, the secondary paper feed subroutine Q0, and the reverse paper feed subroutine R0 are executed as described above, the control unit 200 determines in step S11 whether the document set switch SW4 is ON, that is, the document table 22. Check if there are any documents left on top. If the document set switch SW4 is ON, the control means 200 sets a document flag (step S1).
2) The primary paper feed subroutine P0 is executed again. The primary paper feed subroutine P0 is performed while the original previously conveyed on the transparent plate 8 is being exposed. When the primary paper feed subroutine P0 is executed again in this way, the control means 200 proceeds to step S13 as shown in FIG. 10, and determines whether or not a document exchange signal is sent from the control means 210 of the electrostatic copying machine 2. Confirm. This document exchange signal is sent from the control unit 210 of the electrostatic copying machine 2 to the control unit 200 when the exposure of the document previously conveyed on the transparent plate 8 is completed.
Sent to If there is a document exchange signal in step S13, the process proceeds to step S14, in which the electric motor M2 is driven to rotate forward to operate the transport belt mechanism 100, and the electric motor M3 is driven to drive the reversing roller 134 and the discharge roller 148. The document is rotated and driven to discharge the original on the transparent plate 8 that has been exposed. The original on the transparent plate 8 which has been exposed by this discharge operation is conveyed rightward in FIG.
The document is conveyed to the second document carry-out path 140 through 0. When the electric motor M2 and the electric motor M3 are driven to start the discharge operation of the original, the control means 200 proceeds to step S15, and the original detector S disposed in the second original discharge path 140
Whether W7 has been turned on once and then turned off, that is, whether the rear end of the document conveyed to the second document output path 140 is the detector SW
7 is turned on, the document detector SW7 is turned on once and waits if it is not turned off. If the document detector SW7 is turned on and then turned off, the trailing end of the document is detected. Upon determining that the signal has passed SW7, the control means 200 proceeds to step S16 and sets the timer T to T3. The set time T3 is a time from when the rear end of the document passes through the document detector SW7 to when the document passes through the discharge roller 148, and is set to, for example, 100 msec.
If the timer T is set to T3 in step S16, the control means 200 proceeds to step S17, and the elapsed time T0 after the trailing edge of the document has passed the document detector SW7.
Checks whether the time has reached the set time T3. If the elapsed time T0 has not reached the set time T3, the document discharge operation is continued. If the elapsed time T0 has reached the set time T3, the trailing edge of the document is Since it is determined that the sheet has passed the discharge roller 148, the process proceeds to step S18, and the electric motor M3 is turned off to stop the operation of the reversing roller 134 and the discharge roller 148. The exposed document discharged from the discharge roller 148 in this manner is discharged onto the document discharge tray 20. Next, the control means 200 proceeds to step S19 to check whether or not the document flag is set. If the document flag is set, the control unit 200 determines that the next document has already completed primary feeding. Then, the process proceeds to the secondary paper feed subroutine Q0. If the document flag is not set in step S19, the process proceeds to step S20, where it is determined that there is no document that has been primarily fed, and the electric motor M2 is turned off to stop the operation of the transport belt mechanism 100. After that, the control means 200 returns to the step S1 and executes the respective steps. If there is no original exchange signal in step S13, the flow advances to step S21 to check whether a double-sided copy signal has been sent. If no double-sided copy signal has been sent, the process returns to step S13.
If the double-sided copy signal has been sent, the process proceeds to step S22, in which the electric motor M2 of the transport belt mechanism 100 is driven to rotate forward, the electric motor M3 for driving the reversing roller 134 is turned on, and the reversing sheet feeding subroutine R0 is further performed. Move to

If the document set switch SW4 is not turned on in step S11 in FIG. 9, it is determined that there is no document to be copied on the document table 22 and the process proceeds to step S23, where the document flag is set. Clear and set the latch type solenoid SL2 to O
FF is performed, and the plunger is operated in the separating direction to position the document stopper 84 at the operation position indicated by the two-dot chain line in FIG. At the same time, the control means 200 controls the stopper driving means 8
The timer T is set to T4 in order to diagnose the failure of the latch type solenoid SL2 and the link mechanism 88 which constitute the seventh embodiment. The set time T4 is set to, for example, 100 msec. Next, the control means 200 checks whether or not the elapsed time T0 after setting the timer T has reached the set time T4 (step S24). If the elapsed time T0 has not reached the set time T4, Step S25
Then, it is determined whether or not the stopper position detecting means SW5 is ON, that is, whether or not the document stopper 84 is positioned at the operation position indicated by the two-dot chain line in FIG. If the stopper position detecting means SW5 is not turned on in step S25, the process returns to step S24, and a check is performed until the elapsed time T0 reaches the set time T4. Even after the set time T4, the stopper position detecting means SW5 is not turned on. In this case, the process proceeds to step S26, and the display means 230 displays that the document stopper 84 is abnormal. From this abnormal display, the operator can know that the latch type solenoid SL2 or the link mechanism 88 constituting the stopper driving means 87 has failed.

[0026]

The automatic document feeder according to the present invention is constructed as described above, and the document placing means is attached to a document table connected to the document loading means and rotatably mounted on the upstream end of the document table. A first position that is folded on the original table and an auxiliary table that is positioned at a second position that is pivoted upstream of the original table and is supported at an inclination angle larger than the mounting angle of the original table. And a supporting member projecting upward from the document placing surface and supporting the placed document is provided at the upstream end of the document table, so that the auxiliary table has an inclination angle α larger than the placing angle of the document table.
However, the document placed on the document table and the auxiliary table does not bend because the intermediate portion is supported by the support member. Accordingly, it is an object of the present invention to provide an automatic document feeder capable of preventing a sheet feeding defect caused by a document being bent along a tilt angle between a document table and an auxiliary table.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which a preferred embodiment of an automatic document feeder configured according to the present invention is mounted on an electrostatic copying machine.

FIG. 2 is a schematic sectional view of the automatic document feeder shown in FIG.

FIG. 3 is a sectional view showing a state where a document is placed on document placing means provided in the automatic document feeder shown in FIGS. 1 and 2;

FIG. 4 is an enlarged sectional view showing a carrying-in means of the automatic document feeder shown in FIGS. 1 and 2;

5 is an exploded perspective view of the carrying-in means shown in FIG.

FIG. 6 is an exploded perspective view of a conveyance belt mechanism and a document reversing / discharging unit of the automatic document conveyance device shown in FIGS. 1 and 2;

FIG. 7 is a configuration block diagram of control means provided in the automatic document feeder shown in FIGS. 1 and 2;

8 shows a processing procedure of the control means shown in FIG. 7,
9 is a flowchart showing a part of a main routine.

9 shows a processing procedure of the control means shown in FIG. 7,
9 is a flowchart showing a part of a main routine.

FIG. 10 is a flowchart showing a processing procedure of the control means shown in FIG. 7, and showing a part of a main routine.

11 is a flowchart showing a processing procedure of a control unit shown in FIG. 7, and showing a subroutine of primary paper feeding.

12 is a flowchart showing a processing procedure of the control means shown in FIG. 7, and showing a subroutine for secondary paper feeding.

13 is a flowchart showing a processing procedure of the control means shown in FIG. 7, and showing a subroutine of reverse sheet feeding.

[Explanation of symbols]

 2: Electrostatic copying machine 4: Automatic document feeder 6: Housing of electrostatic copying machine 8: Transparent plate 10: Document regulating member 18: Document placing means 20: Document discharge tray 22: Document table 24: Auxiliary table 33: Document feed-in means 34: Lower guide plate 36: Upper guide plate 38: Forward feed means 40: Forward feed roller 44: Forward feed pressurizing means 48: Pressurizing plate 59: Document regulating plate 60: Document separating mechanism 64: Feeding roller 66: separation belt mechanism 67: drive roller 68: driven roller 69: separation belt 78: drive means 84: document stopper 87: stopper drive means 98: document carry-in path 100: transport belt mechanism 102: drive roller 104: driven roller 106: Endless belt 108: Document conveyance path 114: Registration roller pair 116: Driving roller 118: Driving roller 120: Driving means 128 Document reversing / discharging means 130: first document discharge path 134: reversing roller 135a, 135b, 135c: driven roller 140: second document discharge path 142: reversing path 144: branch control plate 148: drive roller 150: driven roller 152: discharge roller pair 162: drive means 200: control means 210: control means of the electrostatic copying machine 2 220: operation means 221: document placing surface 222: support member 241: support leg of auxiliary table M1, M2, M3: Electric motors FG1, FG2, FG3: rotation amount detecting means SL1: solenoid SL1: latch type solenoid SL3: solenoid CL1: electromagnetic clutch SW1, SW2, SW3: safety switch SW4: document set switch SW5: stopper position detecting means SW6, SW7, SW8: Reflective optical original detector

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masaki 1-28-28 Tamazo, Chuo-ku, Osaka-shi Inside Mita Kogyo Co., Ltd. (72) Inventor Masayuki Kadota 1-2-28 Tamazo-ku, Chuo-ku, Osaka Mita Kogyo (56) References JP-A-1-294123 (JP, A) JP-A-3-192030 (JP, A) JP-A 57-63353 (JP, U) JP-A 64-7132 (JP, A) U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/00 107 G03B 27/62-27/64 B65H 1/00-3/64

Claims (1)

(57) [Claims] 1. An automatic document feeder comprising: a document placing means for placing a document; and a document loading means for sequentially feeding documents starting from the lowest order placed on the document placing means. A document table connected to the document carrying means; a first position rotatably mounted on an upstream end of the document table and folded on the document table; and an upstream of the document table. An auxiliary table that is pivoted to the side and is positioned at a second position that is supported at an inclination angle greater than the mounting angle of the original table, and protrudes upward from the original mounting surface at the upstream end of the original table. An automatic document feeder, comprising: a support member for supporting a placed document.