JPS61186949A - Copying device - Google Patents

Abstract

PURPOSE:To carry an original without generating an image dislocation by a simple constitution, by controlling a carrying means in accordance with the specified position of a reciprocating motion means. CONSTITUTION:When the tip part of an original is inserted from a feed paper port 5 and detected by a sensor 83, and a signal is inputted to a controller 100, the forward motion driving of an original platen 3 is started, and when the position relation of the original platen 3 and a copying machine 1 becomes a prescribed state, a sensor 83a is turned on by an actuator which is provided on the original platen 3. As a result, a feed paper plunger 81 is turned on and the feed of the original is started. Also, by the timing by which an original detecting sensor 83 detects a fact that there is no original, a timer to which the time required for carrying the original by the distance of the detecting sensor 83 and an exposing part 8 is set is started. This timer time is determined by the speed of the original platen 3, and the speed of the original platen 3 is different in accordance with a copying magnification which is set by an operating part 101.

Description

[Detailed description of the invention] Technical field The present invention relates to an apparatus that performs copying according to an original image.

BACKGROUND ART Conventionally, various devices (hereinafter referred to as DF) for automatically transporting sheet originals to the exposure position of the original have been developed in copying machines that copy originals in order to streamline and automate the copying work as much as possible. , and has also been put to practical use.

Also, put the manuscript in the copy machine! ! There are two types: one type exposes the original by fixing the original table on which the original is placed and moving the optical system, and the other type exposes the original by fixing the optical system and moving the original. In the former type of copying machine, the document table is fixed, so it is relatively easy to install the DF, but in the latter type of copying machine, the document table moves, so there are various restrictions such as the structure and weight of the DF. Furthermore, registration control between the leading edge of the document and the leading edge of the transfer paper is difficult and difficult to realize.

Purpose The present invention has been made in view of the above points, and an object of the present invention is to provide a copying apparatus that has a simple configuration and is capable of transporting a document without image shift when moving the document and making a copy. do.

EXAMPLES Hereinafter, examples according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a copying machine equipped with a document feeder according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion of the document feeder shown in FIG. In the figure, 1 is a copying machine with a movable document table (hereinafter referred to as a copying machine), 2 is a document feeder (hereinafter referred to as DF), and 3 is a transparent document table that is connected to a cable or a double-inion rack. The home position shown in solid lines in FIGS. 1 and 2 for the main body of the copying machine is omitted from the drawings because a well-known one is applied as appropriate.

When copying a sheet original (hereinafter referred to as sheet mode), the DF2 switches the copying machine main body 1 to
fixed to the side. A sheet original O (S) inserted into the paper feed port 5 with the upper surface of the DF 2 as the paper feed tray 4 is guided to the document table 3 that moves forward to the left, is exposed to a slit, and is transferred to the document tray when the document table moves back. Sent out on 6th.

When copying a thick original such as a book (hereinafter referred to as book mode), the switching means 38 switches the DF 2 to the original platen 3.
It is fixed to the side and reciprocates together with the document table 3 to perform copying.

The copying machine main body 1 is one to which an electrophotographic process is applied, and includes a slit exposure section 8, an original illumination lamp 8ae8b, reflection mirrors 91 to 94, an imaging lens IO1 and a photosensitive drum 11.
, charger 12) developing device 14, transfer charger 15, cleaning member 16, transfer paper feed section 17, transfer paper guide 18.
19, a fixing device 20, and a tray 21.

In the aforementioned sheet mode or book mode, the document is irradiated by the document illumination lamp 8a when passing through the slit exposure section 8, and the reflected light exposes the photosensitive drum 1 through the reflection mirrors 91 to 94 and the imaging lens 1O. do. The photosensitive drum 11 is previously charged positively or negatively by a charger 12, and an electrostatic latent image corresponding to the original image is formed on the photosensitive drum 11 by the exposure. This electrostatic latent image is developed with toner by the developing device 14, and this toner image is transferred to the transfer paper fed from the transfer paper feeding section at a predetermined timing by the charger 14.
After being transferred by the image forming apparatus 5, the image is fixed by the fixing device 20 and discharged onto the tray 21.

Next, the conveyance operation of a sheet document in the sheet mode will be explained.

The number of copies, paper size, copy magnification, copy image density, and other copy conditions are set using the operation unit 101 (FIG. 3) of the copying machine main body 1. These setting conditions are input to a controller 100 (FIG. 3), which will be described later.

Sheet original 0 (S) to be copied is placed on paper feed tray 4 of DF2.
) (FIG. 2) is placed with the image surface facing downward, and the leading edge of the original is inserted into the feeding sheet path 5a through the paper feed port 5 until the leading edge of the original hits the registration shutter 79. When this document insertion is detected by the sensor 83 and a document presence signal is input to the controller 100, action driving of the document table 3 (in the direction of arrow a) is started. When the positional relationship between the document table 3 and the copying machine l reaches a specific state, an actuator (not shown) provided on the document table 3 turns on the sensor 83a. As a result, the paper feed plunger 81
(Fig. 3) is turned on, and the paper feed roller 77 moves to the paper feed sheet path 5.
The leading end of the document inserted in the document a is held against the paper feed roller 67, and the registration shutter 79 is opened (a second posture shown by the two-dot chain line in FIG. 2). As the document table 3 is driven forward, the paper feed drive and reroller 70 move on the friction plate located on the document table 3, and the rotational force is applied to the paper feed roller 6.
7, and the roller 67 begins to rotate in the document drawing direction. The rotational force of the paper feed roller 67 causes the document to be synchronously conveyed from the paper feed sheet path 5a to the surface of the document table 3 at the same speed as the forward movement speed of the document table 3.1. The documents are conveyed in the forward movement direction of the document table 3 while sequentially coming into close contact with the surface of the document table 3 without slipping between the document table 3 and the document table surface. The conveyed document then passes through the slit exposure section 8 together with the forward document table 3, and is then further conveyed by a conveyance roller 56 while being pressed against the surface of the document table 3. As the document passes through the slit exposure section 8 together with the forward document table 3, the downward image surface of the document is sequentially subjected to slit exposure processing from the leading edge of the document to the trailing edge, and the image of the document is copied. is executed by the copying mechanism within the copying machine main body 1 as described above.

When the document is conveyed as the document table 3 moves forward a and the rear end of the document passes the sensor 83 position, the sensor 83 detects the passage, and the signal is input to the controller 100. .

Further, the document detecting sensor 83 detects the length (length in the feeding direction) of the document fed from the DF 2 to the document table 3, and the forward movement length of the document table 3 is controlled in accordance with the detected length. That is, the forward movement of the document table 3 is controlled to a necessary forward movement distance depending on the size of the document. Furthermore, if the document size is unreasonably large or small, it is detected and the apparatus is controlled to stop. The document table 3, whose forward movement has been stopped, is subsequently switched to backward drive (in the direction of the arrow), and the exposed document is also returned to the original table 3, since it is not pressed by the transport roller 56 together with the document table 3. Transported dynamically.

The number of copies preset here is 1 (single copy)
In this case, the scooping plunger 87 (FIG. 3) is turned on at the same time as the document table 3 starts to be driven back. As a result, the exposed original is deflected and guided by the scooping sheet 85 from the original platen 3 into the discharge sheet path 89, and as the original platen 3 moves back, it enters the sheet path 89. is conveyed in an intermediate manner by a paper ejection roller 64, and is ejected onto the paper ejection tray 6 until the image is upwardly moved until the document table 3 completes its return movement to its initial home position. After returning to the home position, the document table 3 enters a standby state until the next document is set. Further, when the document table 3 returns to the home position and waits, the scooping plunger 87 is also turned off.

In addition, when the number of copies is multiple (multi-copy), even if the document platen 3 starts to be driven back, the scooping plunger 8
7 remains off.

Therefore, in this case, when the document table 3 moves back, the document on the top surface of the document table 3 is also conveyed to the gap 31 between the document table 3 and the pressure bonding seat 30 of the DF 2, and the document holding roller 7
0, the document is pressed against the surface of the document table 3 and is conveyed together with the document table 3, which moves further back. After the document table 3 moves backward to the initial home position and the sensor 83b turns on, the document table 3 is subsequently switched to forward movement again.

As the document table 3 is driven forward again, the document on top of it is also conveyed in the forward direction of the document together with the document table 3, and is transferred to the slit exposure section 8.
, and a second exposure process is performed, and a second copy process is executed on the copying machine main body l side. Original table 3
For the forward movement of the second and subsequent sheets, the forward movement length during the first copying process is stored in the controller 100, and the forward movement is performed in the forward movement length direction. From now on, the document table 3 will be used for the set number of copies.
By repeatedly performing the reciprocating movement, the slit exposure of the document is repeated, and a plurality of copies are sequentially discharged onto the copy tray 21 with the image surface facing upward.

The return movement of the document table 3 and the document ejection operation during the final copy are performed in the same manner as in the case of single copy described above.

FIG. 3 is a block diagram showing a control section of the copying machine shown in FIG. 1. Components having the same numbers as in FIGS. 1 and 2 are the same components. 100 is a controller mainly composed of a well-known one-chip microcomputer with built-in ROM, RAM, etc., and 101 is a key for setting copy conditions such as the number of copies, transfer paper size, copy magnification, and copy image density. In the operating section having a group, /heffer 102
It is connected to the controller 100 via.

103 is a display unit that displays the copying conditions set by the operation unit 101 and abnormalities such as jams; 104 is a lamp reculator for controlling the light amount of the document illumination lamp 8a; It is connected to the. Further, 81 is a paper feed plunger for setting the paper feed roller 77 and the registration shutter 79 to the document feeding i-+f state, and 87 is a scooping plunger for switching the scooping sheet 85. and is connected to the controller 100. Further, it is a D/A converter that converts the digital signal from the 1071t controller 100 into an analog signal, and this analog signal is output to the high voltage control circuit 108 and the developing bias control circuit 109. The high voltage control circuit 108 controls the voltage applied to the charger 12 according to this analog signal. Further, the developing bias control circuit 109 controls the bias voltage applied to the developing device 14 according to this analog signal. Also, 11
0 is a motor control circuit that controls the drive of the motor, and its output controls the photosensitive drum 11. A main motor 111, which is a drive source for conveying the transfer paper, and a document table 112, which is a source of drive for the document table 3, are driven and controlled.

Further, sensors 83, 83a, 83b, jam sensor, etc. (not shown) are also connected to the controller 1 via the buffer 102.
Connected to 00.

FIG. 4 is a flowchart of document conveyance and document table reciprocating movement control executed by the controller 100 shown in FIG. In this example, when the sensor 83 detects the leading edge of the document, the document table 3 starts moving forward, and when the sensor 83a is turned on, feeding of the document starts. When the trailing edge of the document is detected by the sensor 83, a timer is activated from this point on, and the document table 3 is moved back after the timer has been read.

A more detailed explanation will be given below based on the drawings. Step 51
At 00, it is determined whether all copying conditions such as fixing temperature, residual toner, remaining amount of transfer paper, etc. have been met and the copying is possible. If the copying is possible, the process proceeds to step 5iot, where the sensor 83 detects the original. determine whether or not. If the sensor 83 detects the original fρJ, the main motor 111. Original illumination lamp 8a, high voltage control circuit 108. The developing bias control circuit 109 is turned on to start the copying operation. At the same time, the document table motor 112 is turned on and the document table 3 starts to move forward. and step 5103,1
At step 04, it is monitored whether or not the document table 3 is in the forward movement state and whether or not the document table position sensor 83a is turned on. This sensor 83a is operated by an actuator (not shown) such as a cam provided on the document table 3 that moves forward.

This is for detecting a specific position of the document table 3 relative to the main body. When the document table position sensor 83a is turned on, the paper feed plunger 81 is turned on in step 5105 to start feeding the document. This paper feeding timing is a timing for aligning the leading edge of the image on the document table 3 with the leading edge of the document. Then, in steps 5106 and 107, while the document is being fed, the document detection sensor 83 constantly monitors the presence or absence of the document. Then, in step 5108, at the timing when the document detection sensor 83 detects that there is no document, a timer is started, which is set to the time required to convey the document by the distance between the detection sensor 83 and the exposure unit 8. Also, paper feed plunger 8
1 is turned off, the registration shutter 79 is closed, and the paper feed roller 77 is returned to the outside of the sheet path 5a. This timer time is determined by the speed of the document table 3. Note that the speed of the document table 3 varies depending on the copying magnification set on the operation unit 101. Then, in step 5109, the end of the timer is waited for, and in step 110, the forward movement of the document table 3 is stopped and the backward movement is started.

In this way, the registration control of the original and the transfer paper can be performed with high accuracy in the in-tube configuration.

Furthermore, the scanning distance can be optimally controlled depending on the document size, and copying efficiency can be improved.

Note that the various timers mentioned above may be internal timers of the microcomputer or may be external timers.

Effects As described above, according to the present invention, in a device that moves an original for copying, it is possible to transport the original by aligning the leading edges of the original and the transfer paper with a simple configuration and with high precision, thereby preventing image misalignment. Copying efficiency is further improved.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a sectional view of a copying machine equipped with a document feeder to which the present invention can be applied, FIG. 2 is a partial enlarged view of a part of the document feeder shown in FIG. FIG. 3 is a block diagram showing a control section of the copying machine shown in FIG. 1, and FIG. 4 is a control flowchart regarding document feeding. Here, 1 is a copying machine, 2 is a document feeder, 3 is a document table, and 4
is a paper feed tray, 5 is a paper feed port, 5a is a paper feed sheet bus, 6
8a is a document tray, 8a is a document illumination lamp, 10 is an imaging lens, 11 is a photosensitive drum, 56 is a conveyance roller, 67 is a paper feed roller, 79 is a registration shutter, 83 is a document detection sensor, 83a is a document platen position sensor , 100 is a controller, and lot is an operation unit.

Claims (5)

[Claims] (1) a conveyance means for conveying a document; an exposure means for exposing the moving document; a reciprocating means for reciprocating the exposure; a copying means for forming an image according to the image of the document exposed by the exposure means; A copying apparatus comprising: a control means for controlling the conveying means according to a specific position of the reciprocating means. (2) The copying apparatus according to claim 1, wherein the exposure means exposes the original while the original is transported by the transporting means. (3) The copying apparatus according to claim 2, wherein the conveying means conveys the original to the reciprocating means. (4) In claim 1, the control means has a detection means for detecting a specific position of the reciprocating means,
A copying apparatus characterized in that a timing at which the conveying means starts conveying a document is controlled in accordance with an output from the detecting means. (5) A copying apparatus according to claim 3 or 4, wherein the reciprocating means includes an original placing means for placing an original.