JPS6326822Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying apparatus that uses a short-focus, small-diameter imaging element array to form an original image on a photoreceptor.

An array is constructed by arranging a plurality of short-focus, small-diameter imaging elements such as a bar lens or a converging optical transmitter known as a product name "self-occurrence" in one or more rows, and this array forms an image of a document on a photoreceptor. Copying machines that do this are well known.

In such a copying machine, each element works to form a partial image of the document, and these partial images are combined to form the whole image, so if some of the elements become contaminated with dust, uneven density will occur in the image. There is this inconvenience. On the other hand, in such a copying machine, the array is easily exposed to dust from inside and outside the copying machine. Attempts have been made to create a flow to prevent dust from adhering, but these methods are ineffective in preventing contamination during long periods of non-operation.

On the other hand, a non-image area is usually set at a side end in a direction perpendicular to the moving direction of the photoreceptor. This is because the width of the photoreceptor is usually set to be a little longer than the image width, but in this case, there is also a method of forcibly separating the transfer paper from the photoreceptor using the non-image area at one end of the photoreceptor. It is widely used. That is, the transfer paper is conveyed to the transfer section so that one edge of the transfer paper coincides with the non-image area of the one edge of the photoreceptor;
This transfer paper is separated from the photoreceptor by a separating means such as a belt or a claw that is brought into contact with one end of the photoreceptor. In any case, in order to avoid wasting toner, to prevent the separation means from being contaminated with toner and reducing separation performance, and to prevent the side edges of the transfer paper from being soiled, the side edges of the photoreceptor are The non-image area needs to be neutralized after charging and before development, but if this static elimination is performed using a light source other than the document illumination lamp, the device configuration becomes complicated and is also uneconomical, and it is difficult to miniaturize the copying device. inhibit.

The main object of the present invention is to provide a simplified copying apparatus that solves the above-mentioned problems all at once.

Embodiments of the present invention will be described below with reference to the drawings.

Figure 1 shows an example of a copying machine to which the present invention can be applied. In the figure, reference numeral 1 denotes a transparent document table on which an original to be copied is placed, which moves forward and backward to the right on the upper plate 10 of the main body mechanism. After completion, return to the left. Reference numeral 2 denotes a short-focus, small-diameter imaging element array such as the above-mentioned converging light transmitting body or bar lens, and when the document mounting table 1 moves forward, the image of the document placed thereon is transferred to the electrophotographic photosensitive drum 3 ( (rotate in the direction of the arrow) and the slit is exposed. 4 is drum 3
The charger starts operating in synchronization with the start of rotation of the photoreceptor drum 3, and uniformly charges the entire width of the photoreceptor drum 3. The uniformly charged drum 3 is connected to the element array 2.
Image exposure is carried out by means of , and an electrostatic latent image is formed. This latent image is then visualized with toner by the developing device 5. On the other hand, the transfer paper P is sent to the transfer section by the registration rollers 6, and the toner image on the drum 3 is transferred onto the transfer paper by the transfer charger 7.

Here, the transfer paper P is arranged such that one side edge in the direction perpendicular to the moving direction thereof coincides with one side edge in the direction perpendicular to the rotational direction of the photosensitive drum 3 (i.e., the generatrix direction). transported. A separation belt 8 is brought into contact with this side end of the drum 3 at the transfer section position, and the transfer paper P is conveyed so that the side end rests on this belt 8. come. Therefore, in the transfer section, the belt 8 is held between the drum 3 and the above-mentioned side edges of the transfer paper P, but by doing so, the paper P is forcibly separated from the drum 3 after transfer, and the next The image is transported to the fixing process. Incidentally, the end region of the photosensitive drum 3 that the belt 8 is brought into contact with is set as a non-image region. In any case, the transfer paper separated from the drum 3 after transfer is guided to a fixing device 9, where the toner image on the transfer paper is fixed. On the other hand, the surface of the drum 3 after the transfer is cleaned by a cleaning device 11. Note that 12 is a document illumination lamp, and 13 is a reflecting mirror that focuses the emitted light from the lamp 12 onto the document. The lamp 12 is turned on when the document table 3 moves forward, and illuminates the document.

As shown in FIGS. 2 and 3, the machine frame upper plate 10 is provided with a window, the right half of which is a gap opening 14, and the left half of which is a transparent plate 15 made of glass, acrylic resin, etc. In the state shown in FIG. 3, the array 2 faces the document through the gap opening 14, and the lamp 1
The emitted light of No. 2 is irradiated onto the document through the aperture 16 and the transparent plate 15 .

Incidentally, FIG. 2 shows the state before the start of original scanning and after the end of original scanning (including during a pause in the copying operation), and FIG. 3 shows the state when the original table 3 is moving forward (during original scanning).

16 is a cover plate, and a holder 17 holds the array 2.
The arm 19 is fixedly attached to the tip of an arm 19 rotatably attached to the arm 19 by a pin 18. In arm 19,
One end of a tension spring 20 is fixed to the reflecting mirror 13, and the other end of the tension spring 20 is fixed to the reflecting mirror 13, and the cover plate 16 is urged to rotate counterclockwise about the shaft 18 by this spring 20. On the other hand, the other part of the cover plate 16 is provided with a concave bent part 16''.
6'' can be engaged with one end of a lever 22 that is rotatable about a shaft 21.
A pin 23 provided on the plunger of a solenoid (not shown) is engaged with the other end, and when the solenoid is energized and energized, the pin 23 moves upward and moves the lever 22 counterclockwise. It is rotated so that its tip presses down the bent portion 16'' of the cover plate 16. As a result, the cover plate 16 is rotated around the shaft 18 by the spring 2.
It rotates clockwise against the elastic force of 0 and retreats out of the optical path between the original and the array 2. (Figure 3) On the other hand,
When the solenoid is deenergized, the elastic force of the spring 20 causes the cover plate 16 to rotate counterclockwise about the shaft 18, and its bent portion pushes up the lever 22, pushing the pin 2
3 descends. At this time, due to the elastic force of the spring 20, the cover plate 16 enters the position of the gap opening 14 in the optical path and comes into contact with the end of the transparent plate 15, thereby causing the transparent plate 15 and the cover plate 16 to cooperate. This functions to shield the upper part of the array 2 and prevent dust from entering from outside the device.

Now, at the side end of the portion of the cover plate 16 that comes into contact with the transparent plate 15 on the opposite side from where the bent portion 16'' is provided, that is, the side end of the photoreceptor drum 3 that the belt 8 comes into contact with. A reflective portion 16' that is bent and formed so as not to mechanically interfere with the transparent plate 15 during the rotation of the cover plate 16 is protruded from the corresponding side end. (See figure) This reflecting section 1
6' is located below the transparent plate 15 in the state shown in FIG.
The reflecting portion 16' rotates integrally with the cover plate 16, but when the covering plate 16 comes to the position shown in FIG. 3 where it is retracted out of the optical path between the original and the array 2, the reflecting portion
faces the lamp 12 and the light incident end surface of the array 2, and reflects the light from the lamp 12 to the side end of the light incident end surface of the array 2, that is, the photosensitive drum 3.
The incident light is transmitted to the non-image area where the belt 8 contacts and enters the side edge. (See Figures 3 and 4. In Figure 4, L ₁ is emitted by the lamp 13,
This is a representative example of the light beam that is reflected by the original and enters the image area of the photoreceptor drum 3 via the rear array ₂ to form an image of the original in this area. 16' is a representative representation of the light beam that enters the non-image area of the photoreceptor drum 3 through the side end portion of the array 2 after being reflected by the light beam 16'. ) an opening is provided at the side end of the lower reflecting mirror 13;
By appropriately setting the inclination of the reflecting section 16', the reflecting section 1
The light from the lamp 12 reflected by the photoreceptor 6' may be illuminated onto a non-image area of the photoreceptor through the opening of the reflecting mirror 13 without passing through the array 2. but,
Illuminating the photoreceptor through the side edge of the array 2 as described above is more effective in preventing deterioration of the image side edge because the illumination pressure range can be more sharply limited.

Incidentally, reference numeral 24 is a lamp that is turned on when scanning of the original is completed and the document table 1 is reversed from the forward movement to the backward movement and the lamp 12 is turned off, and continues to be lit while the table 1 is in the backward movement.
The entire width of the photosensitive drum 3 is illuminated to eliminate static electricity from the drum surface charged by the charger 4. In other words, the lamp 24 eliminates static electricity from the surface area of the photoreceptor between the trailing edge of the original image formed first and the leading edge of the original image formed next, thereby preventing excess toner from adhering.

In the above apparatus, when the copying machine starts a copying operation and the document table 1 starts moving rightward, the solenoid is energized and moves the pin 23 upward. As shown in FIG. 4, the cover plate 16 is retracted out of the optical path between the original and the array 2, so that the original image scanned by the forward movement of the table 1 is placed on the image forming area of the photosensitive drum 3 on the array. At the same time, the light from the lamp 12 is reflected by the reflecting portion 16' protruding from the side end of the cover plate 16 and enters the side end of the array 2, so that this light is reflected by the charger. The toner is incident on the non-image area at the side end of the photosensitive drum 3 charged in Step 4 to neutralize this area and prevent toner from adhering there during the developing process. Then, at the same time that scanning of the original is completed and the table 1 reverses its moving direction and starts backward movement, the original illumination lamp 13 is turned off and the lamp 24 is turned on instead, and all necessary steps such as image transfer and cleaning of the drum 3 are completed. The drum 3 continues to rotate until the rotation is completed, and the surface of the drum 3 (including the non-image area) that is charged by the charger 4 that is activated while the rotation continues is neutralized. At the same time as the table 1 starts the above-mentioned backward movement, the solenoid is deenergized, and the cover plate 16 enters the position of the gap opening 14 as shown in FIG. Since the upper part of the array 2 is closed, dust is prevented from entering and adhering to the array 2 from outside the device. Since the cover plate 16 is maintained in the state shown in FIG. 2 by the elastic force of the spring 20 even after the copying operation is completed and the copying apparatus is put into rest,
The dust effect persists. (Incidentally, when the copying operation is completed and the rotation of the drum 3 stops, the lamp 24 is also turned off.) In the above embodiment, the reflector 15 may be of a sliding type instead of a rotating type, and the driving force is used to move the document table. You can use the power to

In any case, according to the present invention, when this cover member is retracted out of the optical path, a part of the movable cover member for dustproofing the short-focus small-diameter imaging element array is provided so that when the cover member is retracted out of the optical path, the light from the document illumination light source is reflected to the side edge of the photoreceptor. Since the reflective section is provided to illuminate the non-image area of the image forming apparatus, the apparatus configuration can be simplified.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an example of a copying apparatus to which the present invention is applied, and FIGS. 2, 3, and 4 are explanatory diagrams of essential parts of one embodiment of the present invention. 1 is a document table, 2 is a short focus small diameter imaging element array,
3 is an electrophotographic photosensitive drum, 12 is a lamp, 16
16' is a cover plate, and 16' is a reflective part.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a copying machine in which an image of an original illuminated by light from a light source is formed on a photoreceptor by an array of short-focus and small-diameter imaging elements, when copying is stopped, It enters the optical path and covers the short-focus, small-diameter imaging element array to prevent dust, and when scanning an original, retreats out of the optical path to enable projection of the original image onto the photoreceptor, and a portion faces the light source. 1. A copying apparatus comprising a movable dustproofing means which remains in position and reflects light from a light source by a portion of the movable dustproofing means to illuminate a side end portion of a photoreceptor. (2) The copying apparatus according to claim 1, wherein the movable dust-proof means covers the short-focus, small-diameter imaging element array to prevent dust even during return movement.