JPS6219880A - Image forming device - Google Patents

Abstract

PURPOSE:To combine easily a copying function and a printer function with each other and to constitute a device at low cost by providing an optical shutter capable of controlling light transmissivity at the image formation position of an image forming means which forms an image of reflected light from an original, and forming an optical image passed through the shutter on a photosensitive body. CONSTITUTION:The original platen 2 of the device body 1 where the original is mounted is moved as shown by an arrow (a) and a photosensitive body 3 arranged in the main body 1 is rotated as shown by an arrow. The reverse surface of the original platen 2 is irradiated by a light source 4 and reflected light from the original scanning surface 2a of the original platen 2 is image- formed on a SELFOC lens 5 as the image forming means. The optical shutter 6 is arranged where the original image is formed by the lens 5 and this shutter 6 consists of liquid crystal and is enabled to control the transmissivity of the light under the control of an external electric field. Then, the optical image passed through the shutter 6 is passed through mirrors 7 and 8, a lens 11, and mirrors 9 and 10 to form an image on the photosensitive body 3, simplifying the constitution of the device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an image forming apparatus equipped with a copying function and a printer unit.

[Prior art]

Currently, image forming devices such as printers and copying machines are widely used as devices that play a role in office automation (OA).

Usually, a printer is used as an output device for a pannal computer, and it is common to use a printer to form a digital image by converting digital information stored inside the computer into a digital image using a laser or other device or by thermal conversion, so it can also be used to create an analog image. It was considered to be a separate product with a different mechanism and purpose than a normal copying machine.

However, in a situation where the demand for personal computers is expanding to include households, it is not appropriate to keep copying machines and printers as separate products as described above, and the copying function and printer ja t. A device with @ is desired.

〔the purpose〕

An object of the present invention is to provide an image forming apparatus that combines a copying function and a printer residue with an inexpensive and simple configuration.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 shows i! of an embodiment of this invention. ! In Figure 0, which is a side view schematically showing the configuration, 1 is the main body of the apparatus, 2 is a document table on which a document is placed, and the document table motor (not shown) moves the top surface of the device main body 1 in the directions shown by arrows a and b. It is supposed to be done. Reference numeral 2b denotes a document table cover provided on the upper surface of the document table 2, and a white plate is provided on the back side of the document table cover. 3 is a photoreceptor, which is rotated in the direction of the arrow by a main motor (not shown). 4 is a light source that illuminates the lower surface of the document table 2; 5 is a SELFOC lens as an imaging means for forming an image of the reflected light from the document scanning surface 2a of the document table 2; The configuration is arranged in an array. Reference numeral 6 denotes an optical shutter installed at a position where the SELFOC lens 5 forms an image of the original document. This optical shutter 6 is made by sandwiching a well-known liquid crystal, which can control light transmittance by changing the orientation A of molecules using an external electric field, between glass substrates. A plurality of transparent electrodes are formed in 7 layers, and a transparent electrode facing the transparent electrode is provided on the other surface, and 2 # rear electrodes are provided parallel to the electrode surface.
The structure includes two polarizing plates. 7,8.9',
1 is a reflection mirror that guides the light passing through the optical shutter 6 to the photoreceptor 3 together with a lens 11; 12 is a paper cassette;
Reference numeral 3 denotes a registration roller that temporarily puts the paper supplied from the paper cassette 12 on standby and then sends it out; 14 a charger that charges the photoconductor 3 to a high voltage; and 15 a charger that applies toner to the latent image formed on the photoconductor 3. a developing section for adhering and developing; 16;
17 is a photoconductor cleaner unit; 18 is a fixing roller that heats and fixes the toner transferred to the paper; 19 is a paper discharge tray; 3 Also, Sl is a start position sensor that detects the movement start position of the stacking table 2, and Sl is a tip sensor that detects the tip of the document.

FIG. 2 is a block diagram showing the configuration and input/output status of a control section C as a control means for controlling each section of the apparatus. This control unit C is a microcomputer 20, 21
, buffers 22, 23 . Drivers 24, 25, D/
It consists of a DC controller C1 equipped with an A controller 26, an 18V power supply circuit 27, etc., a motor control circuit 28, etc. In addition, 29 in the figure is a micro switch that detects the overrun of the original platen 2, 30 is a paper feed at the original platen position 9,
A photointerrupter 31 detects the position of a lens, detects a document, detects paper discharge, etc. A light amount sensor 31 detects the amount of light, and is composed of a photodiode or the like. 32 is a thermometer that detects the temperature of the fixing roller 18; 33 is a toner sensor that detects the presence or absence of toner in the developing section 15; 34;
is a microswitch that detects the selected image forming mode.

35 is an operation key 0 or more The detection signals outputted from 30 to 35 are input to the control section C, and based on this, the operations of the following sections are controlled. That is, 36 is a DC load such as the main motor and document table drive motor, 37 is a counter,
38 is a DC load such as a lens moving motor that moves the lens 11, 39 is a high voltage transformer connected to the charger 14, and 4° is a liquid crystal drive circuit connected to the optical shutter 6, which is connected to a latch driver, shift register, etc. consists of 4
1 is an AC driver that drives an AC load 42 such as a fan heater (not shown), 43 is a lamp regulator that drives the light source 4, and 44 is a copy! These are various display parts such as displays. Further, 45 is an interface circuit connected to the control unit C, which communicates with external equipment such as a computer.
There are various known standards for this communication system, and in this embodiment, the R323C system is used for serial communication, and the Centronics Ns system is used for parallel communication. In addition, 46
is a power supply circuit that supplies a predetermined voltage to the 18V power supply circuit 27 of the control section C, the motor control circuit 28, and the like.

In the image forming apparatus having the above configuration, when a copy mode is selected, a signal representing this is sent to the micro switch 2.
9 to the microcomputer 21 via the buffer 23
is input. When the copy switch 35 of the operation section is pressed, this signal is sent to the microcomputer via the buffer 23. (2) is input, and the copying operation is started.

First, it is detected whether or not the document table 2 is at the start position, and if it is not, the document table drive motor is driven to move the document table 2 in the direction of the dashed arrow C-----+) and start. It stops when the position sensor S1 is detected. After this, the main motor and drive motor.

High-voltage charging by the charger 14, paper feeding from the cassette 12,
Control such as lighting of the light source 4 is started, and furthermore, the light shutter 6 is turned on.
A high frequency voltage is applied to all electrodes of this shutter 6 in response to a signal from the control section C, so that all the reflected light from the original is transmitted.

From this state, the document table 2 moves forward ((-)
movement in the direction). ! g When the document stacking table moves forward, the image edge sensor S2 detects the leading edge of the document. At this time, the one-image ahead sensor detects when the image edge is positioned on the exposure section optical axis 4', and based on the signal from this sensor S2, the paper waiting on the distroller 12 is detected. Synchronization is established to match the leading edge of the image developed on the photoreceptor 3 with the leading edge of the image. Then, when the image tip sensor S2 is activated, the document table 2 starts moving, and the reflected light from the document passes through the SELFOC lens, mirror 7°8, lens 11, mirrors 9 and 10, and rotates in a charged state. The third photoreceptor 3 is irradiated with light, and a latent image is sequentially formed in the rotation direction.
The figure is a diagram schematically showing this state. This latent image is further developed in a developing section 15 using a well-known superimposed bias of a high frequency voltage and a DC voltage. The developed image is synchronously transferred to the waiting paper by registration rollers 13, fixed by fixing rollers 12, and discharged onto paper discharge tray 19.

Next, when the apparatus main body l is in an operable state, when a print request signal is input from an external device to the control unit C via the interface 44, the start position sensor S
1 detects whether or not the document table 2 is at the start position, and if it is not at the start position, drives the document table drive motor to move the document table 2 in the direction of the dashed arrow (----4); It stops when the start position sensor S2 detects the start position. At this time, a white plate provided on the document table cover 2a is positioned above the image line in the document surface exposure section 4'. Thereafter, controls such as high-voltage charging, paper feeding, and lighting of the light source 4 are started in the same way as in the copy mode described above, and a print permission signal is output from the control section C to the external device via the interface 44. Print information input from an external device is first stored in the microcomputer 21.
By specifying the address of the ROM that is stored in the RAM of the
Bit information in the image line direction of the print information is transmitted as serial data to the shift register of the liquid crystal drive circuit 40. At this time, the time required to transmit the bit information of 1 line of the image is within 1 m5 ec, and when the bit information for 1 life is collected, the latch driver is driven and the optical shutter 6 is controlled. In addition, the optical shutter 6
The time during which is driven by the latch driver is 1 ms
ec, during which one line of beat/beat data is sent to the shift register repeatedly. This first line output corresponds to the image edge of the original in the copy mode, and is used to send the paper waiting at the registration roller 1'°3 to the transfer unit 16 at this point, as in the copy mode. Generate a synchronization signal.

On the other hand, the light emitted from the light llA4 is reflected by the white plate of the document table cover 2a, and then is focused on the optical shutter 6 through the SELFOC lens 5. At this time, the optical shutter 6 is divided into a light passing part and a light blocking part by the above-mentioned control.
The light irradiated onto the light passing portion is again focused by the lens 11 and then irradiated onto the charged photoreceptor 3, forming a latent image. Thereafter, the above-described development, transfer, and fixing operations are performed, and the paper on which image formation has been completed is discharged to the paper discharge tray 19.

In this manner, in this embodiment, well-known copying operations can be performed in the copier mode, and printing of information input from an external device can be performed in the printer mode.

Note that by changing the synchronization signal generated for each line of the image in the printer mode of the above embodiment, direct input of a video signal sent from an external device can be easily realized.

Furthermore, in the above embodiment, the copying machine mode and the printer mode are selectively operated. It is also possible to control the optical shutter 6 with a control signal from the section to record characters or the like in the copied image.

〔effect〕

As described above, the present invention has the advantage that an image forming apparatus that combines copying functions and printer operation can be realized with a simple and inexpensive configuration.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a schematic configuration of the present invention, FIG. 2 is a block diagram showing the configuration of the control unit and input/output status of the device shown in FIG. 1, and FIG. 3 is a document table shown in FIG. FIG. 3 is a diagram schematically showing the state of the path of light from to a photoreceptor. 2......Original table 2a...Scanning surface

Claims (3)

[Claims] (1) A light source that irradiates light onto the scanning surface of the document table, an imaging device that forms an image of the reflected light from the document placed on the scanning surface, and a light provided at the imaging position of the imaging device. An image forming apparatus comprising: an optical shutter whose transmittance can be controlled, and an optical image transmitted through the optical shutter is formed on a photoreceptor. (2) The image forming apparatus according to claim 1, wherein the optical shutter is made of liquid crystal. (3) The image forming apparatus according to claim 1 or 2, wherein the image forming means is a short focus lens array.