JPS5955464A - Picture controller - Google Patents

Abstract

PURPOSE:To suppress toner consumption and to reduce staining with toner by forming a white latent image area at a nonpicture area which is formed as a result of continuous magnification variation, and then driving and controlling an LED array according to magnification for optical destaticization. CONSTITUTION:An original pressure plate 10 is l longer than an original, so the white latent image area l' with length MXl is formed in a latent image area on a photosensitive drum adjacently to an area L' with length MXL which is obtained by multiplying the length L of the original by variable magnification M. In this case, whether the optical destaticization of a part S is carried out or not is not important and an LED array 4 of elements 4a, 4b arranged in the axial direction of the photosensitive drum at intervals of pitch D equal to or less than the minimum width l' of the white latent image is brought under lighting control so that areas on the right-hand side of the area S are all discharged and all areas on the right-hand side are not discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image control device that performs so-called continuous magnification black erasure control, and particularly to a photosensitive I-ram when the magnification of a recorded image is changed in series. The present invention relates to an image control device that prevents toner from entering a non-image area of an image.

Prior Art Conventionally, in this type of copying machine, there is a process (
In the direction of rotation of the drum, the blackening process could be carried out by means such as those already provided, but in the direction parallel to the drum axis, small miniature lamps are usually arranged to achieve the selected magnification. This was done by flashing the lamp accordingly. However, in the case of continuous magnification change, the lamp must be blinked continuously, and this cannot be effectively realized because the pitch is coarse with ordinary miniature lamps. In addition, methods using light emitting and light elements such as LEDs (light emitting diodes) have also been proposed, but even these
There is a problem in that this process cannot be performed for continuous magnification changes that are less than the pitch interval of . In addition, a method of arranging a movable shield in front of the lamp and continuously blocking the light from the lamp with this shield has been proposed in 1, but it suffers from the adverse effects of light diffraction and diffused reflection, and also suffers from a This has not been realized due to problems such as complexity. However, ideally it would be good to have an element that is a very small point light source that does not completely destroy the speed of light and is arranged at a very small pitch, but such an ideal element is also Not provided.

1-1 The present invention has been made in view of a series of points.
Also by l.ner! It is an object of the present invention to provide an image control device that can obtain good-looking copies with very little IJ distortion.

Furthermore, it is an object of the present invention to provide an image control device that is simple in structure and inexpensive, which can effectively use an LED array, save power and reduce heat generation.

Example The present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a small example of a schematic representation of the main parts of a Carlson process type copying machine to which the present invention is applied. Drum” second photoreceptor
After being uniformly charged by the loader 2, the original f7J
It is exposed to reflected light 3 from (not shown) to form a latent image, and the latent image is developed by a developing device 5. -・Power.

The copy paper (recording paper) 8 is conveyed under control so that it coincides with the developed image at the transfer position, and is fed to the transfer charger 6.
After being transferred by.

It is removed by charger 7 and 211 f? Jl is done. 4 is the main part of the present invention, and L for blackening the non-image area, which will be described later.
This is an ED array.

FIG. 2 shows several examples of the side view of the document table portion of the copying machine shown in FIG. Without further discussion, lower the original 11 to be copied onto -1, -1, of the original mounting crow 12 with one side referenced. When copying is performed at a variable magnification M with the pressure plate 10 lowered, the image of the original 11 whose length L is MXL as shown in FIGS. 3(A) and 3(B). The image is magnified to a length of , and is formed as a latent image on the photosensitive drum l'-.

The latent image area of the original on the photosensitive drum 1 is indicated by L'. In addition, at this time, the original pressure plate lO is provided so that its length is longer than the original by the length of the original document, and a white back side portion of the length of the sentence remains. A white latent image 1]2 with dimensions corresponding to 1 is formed on the photosensitive drum 1]2. 1a shows a latent image formed on the photosensitive drum l,
A shaded area 1b in the figure shows a dark latent image formed on the photosensitive drum 1''. Further, in the figures, arrows indicate the axial direction of the drum.

Here, if the magnification is changed continuously when there is no white latent image 'of the original #f4 pressure plate 10, the boundary line between the dark latent image 1b and the latent image L' of the original will change continuously. , it is necessary to continuously irradiate light to the dark area Δ1) that must be erased. However, in this example, since there is a white latent image area text' when changing the magnification, L'
is the area where light must not be irradiated, and ,Q,' is the area where light may or may not be irradiated, and the shaded area 1 in the figure
b is for light:! I; (Since this is an area where you have to cross over, I arranged them with a pinch D (Ljlj in Figure 5) that is smaller than or equal to Wataru', and the ED array 4 is used to convert the two crossed light according to the magnification M. If irradiation is performed appropriately, at least the shaded portion ib can be always irradiated, and the region L' can be absolutely not irradiated.

4(A) and 4(B) show schematic diagrams of the optical control circuit of the original machine shown in FIG. 1. Each element h4a, 4b, etc. of the LED array 4 corresponds to the Tigit line D.
, to and scan line S.

1S, . . . are respectively connected as the intersections of the matrices, and based on the scaling factor, ! ! Selected LED
The electric lamp is lit by the dynamic lighting circuit 20.

FIG. 51 shows the relationship between the variable magnification A and the operation of the elements of the LED array 4 in FIG.
The lighting of each element of S is controlled so that at least all of the charge is removed from the area I to the right side of the figure.

The lighting is controlled so that at least all of the area from the area S to the left side of the figure is not completely neutralized and the latent image of the document is not damaged.

As explained above, according to the present invention, a white latent image is created in the area that becomes a non-image area due to the C change. There is no need to consume toner, and since there is no excess toner, it is possible to obtain clean copies. Further according to the present invention.

Since the LED array can be used effectively, low power consumption and low heat generation can be obtained, and the reliability of the device can be improved at low cost.

Furthermore, if the so-called Guinamink lighting method is applied to drive the LED array as in this embodiment, the drive circuit becomes simple and the current consumption can be further reduced.

In this example, the case where the reference point is 1.0 cm on one side is shown, but it goes without saying that the case where the reference is in the center is also suitable.

Further, although this embodiment shows a control means using an LED array, the same effect can be obtained even when an LCD shank array is used. In addition, in this example, the areas where light may or may not be used are formed from an MC41J pressure plate or by sliding a plate with a white back to match the edge of the document. It's okay.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram showing an example of the internal configuration of a copying machine to which the present invention is applied, FIG. 2 is a front view showing an example of the configuration of the document table part of the 11Δ duplicator, and FIG. 3 (A) and (B) is a front view and a four-part plan view showing the longitudinal relationship between the original and the photosensitive drum in Figure 2, and Figures 4 (A) and (B) are of the copying machine in Figure 1. Preemptive? A bronch diagram and an enlarged sectional view of the mounting part showing an example of the configuration of the #11 circuit, and FIG. 155 are a small explanatory diagram of the relationship between the LED array of FIG. 4 and the variable magnification. 1... Photosensitive drum (photosensitive member), 2...'+'rP electric appliance, 3... Reflected light, 4... LED array, 4a, 4b, 4c ~... Each element of the LED array, 5... Developing device, 6... Transfer band remover, 7... Band remover, 8... Copy paper (recording paper), 8... Conveyance path. IO... Original pressure plate, 11... Original, 12... Original placing glass, 20... Guinamik lighting circuit, Dl ~ D2... Disintegration line, S, , S,
~...Scan line, H... Weird ego rate
, し... Length of the manuscript. L'...Latent image area of the original, Sentence...Remaining length of the back side of the original, 9,'...White latent image area caused by the original pressure plate. Special, Negative Applicant: Canon Co., Ltd. Figure 1
Figure 2 Figure 3

Claims (1)

[Scope of Claims] l) In an electrophotographic M machine that forms a latent image ψ on a photoconductor by light reflected from the original, a latent image of the original is formed adjacent to the original latent image depending on the magnification. A white latent image forming means for forming a white latent image by reflected light; a light eliminator arranged at intervals of a pinch D equal to or smaller than the minimum width of the white latent image; An image control device comprising a control means for controlling drive according to a magnification, and the control means performs control to suppress excess toner consumption. 2. The image control device according to claim 1, wherein the optical charge eliminating means is an LED array or an LCD shutter array arranged at the pitch D.