JPH0667309A - Copying machine - Google Patents

Abstract

PURPOSE:To relieve load in a mechanism for a copying machine, to accurately position a document and to improve operability by providing an optical system moving means for moving the optical system based on the detection result of a mode detecting means. CONSTITUTION:When a printing switch is turned on, a copying mode is judged (whether or not an automatic document feeder(ADF) is used), and in the case of not using the ADF, the document is set on an document placing table by taking a corner as a reference (manual mode), so that a lens is moved in accordance with the aforesaid setting. And then, a paper size L is confirmed, next, copying magnification (m) is confirmed. The paper size L and the copying magnification (m) are stored by a register, so that the lens moving extent in the horizontal direction is calculated based on each data, and the lens is moved by the calculated length in the horizontal direction. Next, in the case that the magnification is not (m=1), the lens is moved back and forth in accordance with the copying magnification.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, and more particularly to improvement of a document setting system.

[0002]

2. Description of the Related Art A general copying machine is equipped with a document table of a size capable of setting an A3 size document, but when setting a document of a smaller size, there are two types of setting methods. It was The first is the so-called center reference method. This is a method of setting the center of the document in the width direction at the center of the document table regardless of the document size (paper size). The second is the so-called corner reference method. This is a method in which the corner of the original is set to the corner (generally left front) of the original regardless of the original size (paper size). When the original setting method is the center reference, the paper is also conveyed by the center reference, and when the original setting method is the corner reference, the paper is also conveyed by the corner reference.

In the center-based conveyance system, the roller position and the paper guide can be arranged symmetrically with respect to the center of the paper / document, and the load distribution on the paper or document becomes even. There is an advantage that there is little feeding failure due to uneven wear and high reliability.

On the other hand, in the manuscript table operated by a human, it is difficult to position the manuscript at the center of the platen glass even if it is indicated by the index, and the manipulating method is to set the manuscript against one of the corners. Is excellent.

[0005]

The conventional copying machine adopts only one of the center reference method and the corner reference method, and it can be switched depending on the document setting mode (ADF mode, manual mode). could not.

An object of the present invention is to provide a copying machine which is mechanically always stable and easy to operate.

More specifically, the automatic document feeder /
An object of the present invention is to provide a copying machine capable of achieving both high reliability and operability by allowing the paper transport mechanism to transport on the basis of the center and enabling the corner reference in the manual setting mode on the platen.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a document table,
A manuscript manual setting index provided in one corner of the manuscript table, an optical system for transmitting a manuscript image on the manuscript table to the photoconductor, and a plurality of manuscript sizes can be set. An ADF to be conveyed, a sheet conveyance system capable of setting plural sizes of copy sheets and conveying any size of copy sheets on the basis of a center, and a mode detecting means for detecting whether a document is manually set or set by the ADF. And an optical system moving means for moving the optical system based on the detection result of the mode detecting means.

[0009]

According to the present invention, copying paper is conveyed on the basis of the center to ensure mechanical reliability. When a document is conveyed by the ADF, it is performed based on the center. At this time, the optical system may be located at the center. When setting a document manually, use the corner reference that allows easy positioning. At this time, the optical system needs to be positioned between the center reference photoconductor and the corner reference document table. The mode detection means detects the copy mode and moves the optical system based on the detection result.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic configuration diagram of a main part of a copying machine including an optical unit according to an embodiment of the present invention.

A glass platen 10 is provided on the upper surface of the main body 1. This document table 10 has a maximum document size (A
It is configured to fit 3). This manuscript table 1
An automatic document feeder (ADF) 12 is provided on the display unit 0 so as to be openable and closable. When a document is set on the document tray of the ADF 12, this document is detected by a sensor (not shown),
When the print switch is turned on, the document is automatically fed (ADF mode). Also, open the ADF 12 to open the document table 1
When the original is set directly on 0, the original sensor on the original table 10 detects this and the print switch is turned on to copy the original (manual mode). An optical device 2 including a light source, a mirror, a lens 13 and the like is arranged under the document table 10. The reflected light of the original travels along the optical path formed by the mirror of the optical device 2 and passes through the photoconductor 30.
At the exposure point P. The photoconductor 3 rotates clockwise in the drawing, and around the periphery thereof, a developing device 4, a transfer charger 5, a peeling charger 6, a cleaning device 7, a charge eliminating lamp 8 and a charging charger 9 are arranged downstream from the exposure point P. Has been done. At the lower right side of the main body 1, there is provided a paper feeding unit 15 including a cassette for storing radiation paper, a paper feeding roller, a timing roller and the like. The paper in the cassette is fed by turning on the print switch. It is conveyed toward the transfer portion of the photoconductor 3. A fixing device 16 and a paper discharge unit 17 are arranged on the left side of the photoconductor 3.

The operation of the copying machine having the above configuration will be described.

First, the scanning unit (light source and mirror) of the optical device 2 scans a document on the document table 10, and the reflected light of the document irradiates the photoconductor 3 at the exposure point P. As a result, an electrostatic latent image is formed on the surface of the photoconductor. Toner is attached to the formed electrostatic latent image in the developing device 4 to form a toner image. This toner image is transferred to the transfer charger 5.
At that time, the image is transferred onto the sheet fed from the sheet feeding section 7 at the same timing.

After the development and transfer of the photosensitive member 3, the cleaning device 7 removes the residual toner, and the charge removal lamp 8 removes the charge. On the other hand, the paper on which the image has been transferred is peeled from the photoconductor 3 by the peeling charger 6 and conveyed, and is subjected to heat treatment by the fixing device 16 to fix the image, and then discharged to the paper discharge unit 17.

When a document is set using the ADF in such a copying machine, as shown in FIG. 2, guides 50 (50R, 50L) contacting both sides of the document are interlocked to keep the document 51 at the center. regulate. In the paper cassette, the side regulating plate 60 can be moved according to a plurality of types of sheet sizes as shown in FIG. 3, but the side regulating plate 60 is adjusted according to each sheet size with the center as a reference.
Is designed to be fixed. Therefore, the original set in the ADF and the copy paper fed from the paper cassette are conveyed on the basis of the center regardless of the size.

On the other hand, as shown in FIG. 4, the document setting method on the document table 10 is a corner placement method. That is, the manuscript 11 is set by aligning the corners of the manuscript with the manual setting index 10a provided at the left front corner (corner) of the manuscript table 10. By setting the document on the basis of the corner, the document position can be determined more accurately than by relying on the index of the center reference, and the operability is improved.

However, in order to switch the document setting position between the center reference and the corner reference and to form an image in accordance with the center reference paper in any case, the lens is orthogonal to the optical axis according to each mode. Need to be moved in the direction (hereinafter referred to as "left-right direction"). This mechanism is shown in FIG.

In FIG. 5, the lens 12 is fixed on the bed 20. Bed 20 is rail 2 on bed 21
5 is mounted so as to be movable in the left-right direction. Further, the bed 21 is movable along the rail 29 in the optical axis direction (hereinafter referred to as “front-back direction”). The rail 29 is fixed to the copying machine main body 1. The bed 20 is moved by a motor 22 fixed on the bed 20, a pinion gear 23 driven by the motor 22, and a rack gear 24 fixed on the bed 21 in the left-right direction and meshing with the pinion gear 23. In addition, movement of the bed 21 is performed by the motor 26 fixed on the bed 21,
A pinion gear 27 driven by a motor 26 and a pinion gear 2 fixed to the main body 1 of the copying machine in the front-rear direction.
This is done by a rack gear 28 that engages with 7. The operation control of the motors 22 and 26 is performed by a control unit (not shown).

FIG. 6 is a diagram for explaining a lens position control method. In the figure, the paper size to be copied is L ₀ ,
When the copy magnification is m, the size of the manuscript that can be copied is ₀ / m.
Becomes Since the sheet is conveyed on the basis of the center, the original placement reference (corner) of the original table is set to O and the opposite end of the sheet is set to I.
Then, the lens center needs to be located at Z on the straight line OI, and 0Z: ZI is a function of m. Since Z is displaced from the center of the paper, this displacement is Δ.

Here, if the focal length of the lens is f,
In the case of fixed focus, the relational expression of a = (1+ (1 / m)) f b = (1 + m) f holds (In the case of a variable focus lens, a + b = constant, and a and b are functions of m. .).

Since the triangle OZO 'and the triangle IZI' are similar, OO '= L ₀ / 2-Δ II' = L / 2 + Δ, so (L ₀ -Δ): a = (L / 2 + Δ) ): B From these, Δ = 1/2 · (mL ₀ −L) / (m + 1). L ₀ : Since it is constant (maximum document size), Δ is obtained by L: document size, m: magnification.

FIG. 7 is a flow chart showing the operation of the control section of the copying machine. This operation is a flowchart showing the operation when the print switch is turned on. When the print switch is turned on, the copy mode (whether to use the ADF or not) is determined (n1). When the ADF is not used, the original is set on the original table 10 based on the corner reference (manual mode), and the lens is moved accordingly. First, the paper size L is confirmed (n2). Next, the copy magnification m is confirmed (n3). These are stored in the register. The lens movement amount ΔY in the left-right direction is calculated from these data by ΔY = (mL ₀ −L) / 2 (m + 1) (n4). The lens is moved in the left-right direction by this length (n5, n6).

Next, when the magnification is not equal (m = 1), the lens is moved back and forth in accordance with the copy magnification (n7, n).
8). After the above operation, the copy operation is started (n
9).

On the other hand, in the case of the ADF mode, since the original document is also conveyed with reference to the center, it is not necessary to move the lens in the left-right direction. Therefore, the operations of n2 to n6 are skipped and the process directly proceeds to n7.

[0025]

As described above, according to the present invention, since the conveyance of the copy sheet and the conveyance of the original when the ADF is used are performed with reference to the center, the load on the mechanism of the copying machine is small. On the other hand, when a document is manually set on the document table, the document can be set on the basis of the corners, so that the document is accurately positioned and the operability is improved.

[Brief description of drawings]

FIG. 1 is a schematic structural diagram of a copying machine that is an embodiment of the present invention.

FIG. 2 is a block diagram of the ADF of the copying machine.

FIG. 3 is a configuration diagram of a paper cassette of the copying machine.

FIG. 4 is a view showing a document table of the copying machine.

FIG. 5 is a diagram showing a lens moving mechanism of the copying machine.

FIG. 6 is a diagram showing a method of calculating a lens moving distance in the copying machine.

FIG. 7 is a flowchart showing the operation of the control unit of the copying machine.

[Explanation of symbols]

 10-Document Plate 10a-Manual Setting Indicator 11, 51-Document 12-ADF 13-Lens 50-Document Guide (of ADF) 60-Side Regulation Plate 61 (of Paper Cassette) 61-Copy Paper

Claims (1)

[Claims] 1. A document table, an index for manually setting a document provided at one corner of the document table, an optical system for transmitting a document image on the document table to a photoconductor, and a document of multiple sizes can be set. , An automatic document feeder that conveys the center of any size original to the center of the original table, and multiple sizes of copy paper can be set, and any size of copy paper can be transferred to the center of the photoconductor A paper transport system, a mode detecting means for detecting whether a document is manually set or set by the automatic document feeder, and an optical system moving means for moving the optical system based on the detection result of the mode detecting means, A copying machine characterized by having.