JPH03163464A - Image forming device - Google Patents

Abstract

PURPOSE:To surely perform fixing under simple control by providing a means which inputs the size of a transfer paper and the number of paper where an image is consecutively formed and controls the time interval of a fixing action in accordance with the obtained size and the number of paper. CONSTITUTION:By inputting the number of copies and the size of the transfer paper and inputting a command for starting copying from a keyboard KB, a copying speed corresponding to the size of the transfer paper and the number of consecutive copied sheets which are previously stored in the ROM of a microcomputer MC, that means, the fixing interval time is set. When the time is expressed as second/sheet, it is 0.3 in the case of <200 sheets of A3 size paper, 0.5 in the case of >=200 sheets of A3 size paper, 0.2 in the case of <200 sheets of B5 size paper and 0.4 in the case of >=200 sheets of B5 size paper. A motor driving device DR, respective clutches and respective power sources are mechanically controlled by the MC. Thus, the temperature of a fixing device is held within the range of a temperature at which fixing can be possible, and fixing is surely performed.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an image forming apparatus such as a PPC or a laser printer.

(B) Conventional technology Conventionally, in this type of image forming apparatus, when the number of images to be formed is large or when the size of the transfer paper is large, the temperature of the fixing device decreases, resulting in poor fixing. It is known that the image forming speed is controlled from temperature information of the fixing device (for example, Japanese Patent Laid-Open No. 14306/1983).
(See Publication No. 7).

(c) Problems to be Solved by the Invention However, such conventional image forming apparatuses not only require a detection means for detecting temperature information of the fixing device, but also require complicated control to process the information. There was a problem with that.

This invention was made in consideration of these circumstances,
The present invention provides an image forming apparatus that can perform fixing reliably with extremely simple control by controlling the time interval of the fixing operation based on the number of images to be formed and the transfer paper size that are input in advance.

(2) Means for Solving Problem R This invention provides an image forming system configured to repeat the operation of transferring and thermally fixing a toner image onto transfer paper of a desired size to continuously form images on a desired number of sheets. The apparatus is characterized in that it comprises an input means for inputting the transfer paper size and the number of continuous image formation sheets, and a means for controlling the time interval of the fixing operation in accordance with the input transfer paper size and the number of image formation sheets. Picture 1g is an L-shaped device.

(e) When the transfer paper size and the number of sheets of continuous image formation are manually input from the operational manual means, the time interval of the fixing operation is controlled accordingly. In other words, when there are many images to be formed or when the transfer paper size is large, the time interval between fixing operations becomes longer.
As a result, the degree of sharpness required for fixing by the fixing device is sufficiently ensured, so that reliable fixing can be performed.

(F) EXAMPLES Hereinafter, this invention will be described in detail based on the examples shown in the drawings. This invention is not limited by this.

FIG. 1 is an explanatory diagram of the configuration of an electrophotographic copying machine showing one embodiment of the present invention, in which 1 is a main body, 2 is a contact glass on which a document is placed, and 3 is a document mat that covers the contact glass 2 in an openable and closable manner. , 4 is an exposure lamp for exposing and scanning the original, 5
6 is a reflection plate; 6 is a first mirror that reflects image light from the original; 7 is a second mirror that reflects light from first mirror 6; 8 is a second mirror that reflects light from first mirror 6;
4a is a first movable unit equipped with an exposure lamp 4, a reflection lamp 5 and a first mirror 6 for exposure scanning; 7a is a second mirror 7 and a third mirror 7; A second moving frame is mounted with a mirror 8 and follows the first moving frame 4a; 9 is a photosensitive drum rotating in the direction of the arrow; lO is a photosensitive drum that transmits light from the third mirror 8 via a fourth mirror 11; An imaging lens that forms an electrostatic latent image by focusing on the surface of 9! 2 is a developing device that develops the electrostatic latent image formed on the photoreceptor drum 9, 13a is a cassette that accommodates A3 size transfer paper 14a, 13b is a cassette that accommodates B5 size transfer paper + 4b, and 15a is a transfer A paper feed roller +5b feeds the paper I4a, a paper feed roller +5b feeds the transfer paper +4b, a registration roller l6 transports the transfer paper in synchronization with the rotation of the photosensitive drum 9, and l7 transports the registration roller l6. a transfer charger that transfers the developed image on the photoreceptor drum 9 onto the transferred transfer paper; l8 is a separation charger that separates the transferred transfer paper from the photoreceptor drum; l9
2 is a conveyance belt that conveys the separated transfer paper; 20 is a fixing roller that fixes the transfer paper conveyed by the conveyance belt; and 2l is a discharge roller that discharges the fixed transfer paper to a tray 22. . Further, 23: a cleaning unit for removing residual toner on the photoreceptor drum 9; 23a is a cleaning blade that is activated during copying to scrape off the toner on the surface of the photoreceptor drum 9; 24 is a cleaning unit for removing residual charge on the photoreceptor drum 9; A static eliminating lamp 25 is a photosensitive drum 9 to be removed.
This is the main charger that charges the battery uniformly.

FIG. 2 is a block diagram of the control section of the embodiment shown in FIG. 1, and MC is a CPU. The microcomputer KB, which has a built-in ROM, RAM, I/O board, etc., is a keyboard for inputting various copying conditions such as the number of continuous copies and transfer paper size, and various commands, and a lamp power source for the static elimination lamp 24. DR is a motor drive device, and the first moving frame 42L
1 2nd moving unit 7+L. Photosensitive drum 9, developing device I2,
Cleaning unit 23, paper feed rollers 15i, 15b
1 registration roller 16, conveyor belt l9, fixing roller 2
0, and a motor (not shown) that drives the discharge port and the like. The rotational force of the motor driven by the motor drive device DR is applied to the first and second moving frames 4a and 7a via the clutch Ct, to the photosensitive drum 9 via the clutch C2, and to the paper feed roller via the clutch C3a. 15a
, to the paper feed roller 15b via the clutch C3b, and to the registration roller 16 via the clutch C4. PI is a power source that applies voltage to the main charger 25, P2 is a power source that applies voltage to transfer charger l7,
P3 is a power supply that applies voltage to the separate charger l8, P4
P5 is a power source that applies a developing bias voltage to the developing device fill2, and P5 is a power source that applies a voltage to the heater of the fixing roller 20. The microcomputer MC receives the output from the keyboard KB and outputs the lamp power supply LPI. LP2
, motor drive device DR, power supply PI-P5. clutch CI
, C2, clutches C3a, C3b and clutch C4.

The main operations in such a configuration will be explained using the flowchart shown in FIG.

The number of copies and transfer paper size are input from the keyboard KB (step +01), and ? J [The command to start copying is manually issued (step 102), the microcomputer MC
Since the copy speed, that is, the fixing interval time corresponding to the transfer paper size and the number of continuous copies as shown in Table 1 is stored in advance in rlOM, if the input f2 copy paper size is A3, The fixing interval time is 0.3 seconds,
In the case of B5, each time is set to 0.2 seconds (step!03).

Table 1 Then, the continuous copying operation is started (step 1 O4), and the number of copies shown in Table 1 is made, that is, 100 copies for A3 size and 200 copies for B5 size. If further copying is to be performed (step l05), the fixing interval time is increased to 0.5 seconds for A3 size and 0.4 seconds for B5 size, and the copying operation is continued. Operation will resume. And step 1
At step 01, the copying operation ends when the input set number of copies has been copied. In addition, in step +01, the input setting number of copies is 100 in A3 size.
If the number of copies is 200 or less in B5 size (step 105), the set number of copies are made at the copy speed set in step 103, that is, the copy interval time (step 106).

In this way, the copy speed can be adjusted according to the transfer paper size and the number of images to be formed, that is, in this embodiment,
Since the time interval of the fixing operation is controlled, the surface temperature of the fixing roller is ensured within the fixable temperature range, and reliable fixing is performed.

(G) Effects of the Invention According to this invention, the time interval of the fixing operation is controlled in accordance with the number of sheets of continuous image formation and the transfer paper size, so the temperature of the fixing device is maintained within the temperature range that allows fixing. ,
Reliable fixation is achieved.

[Brief explanation of the drawing]

No. IrXJ is an explanatory diagram of the configuration of an electrophotographic abdominal camera showing one embodiment of the present invention, FIG. 2 is a block diagram of the controller of the embodiment shown in FIG. 1, and FIG. 3 is an embodiment shown in FIG. 2 is a flowchart illustrating the main operations of FIG. l...Body, 2...Contact glass, 3...Original mat, 4...Exposure lamp, 5...Reflector, 6 ...First mirror 7...Second mirror, 8...Third mirror 9...Photosensitive drum, 10...Image formation Lens, 1l...No. 4 mirror l2...
- Developing device, 13a. 13b...Cassette, 1
4a. 14b...Transfer paper, 15a. 15b...Paper feed roller, l6...
...registration roller! 7...Transfer charger, l8...Separation charger, 19...Transport belt, 20...Fixing roller, 2-ton...Discharge a- La, 22...Tray, 23...Cleaning unit, 24...
... Static elimination lamp, 25 ... Main charger, MC ... Microcomputer, KB ...
··keyboard. Figure 9 Figure 3

Claims (1)

[Claims] 1. In an image forming apparatus configured to repeat the operation of transferring and thermally fixing a toner image onto a transfer paper of a desired size to continuously form images on a desired number of sheets, An image forming apparatus comprising: input means for inputting the number of continuous image formation sheets; and means for controlling a time interval of a fixing operation in accordance with the input transfer paper size and the input number of image formation sheets.