JPS5821764A - Copying machine - Google Patents

Abstract

PURPOSE:To obtain a copying machine which can convert magnifications such as unmagnification, scale down and magnification of a lens accurately and can be reduced in size by disposing selfoc lenses selectively movably in an optical course between an original and a photoreceptor. CONSTITUTION:The light irradiated onto the original 11 on an original placing platen 12 is irradiate to a photoreceptor 2 through a Selfoc lens 17a or 17b in the mid-way of an optical route 27, whereby the image of the original 11 is formed and an electrostatic latent image is formed on the photoreceptor 2. The Selfoc lens 17a is for unmagnification, and the 17b is for scale down or magnification. The lenses are supported respectively on both side parts of a supporting member 20 extending in parallel over roughly the entire length of a photosensitive drum 3 above the drum 3. Since the lenses are turned and are moved freely changeably to the route 27 by one-turn driving motion of a motor 24, the scale-down copying and macro-copying are performed freely changeably.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copying machine capable of copying at the same size and at a predetermined reduction or enlargement ratio.

In a conventional copying machine, for example, when performing a double copy at a predetermined reduction magnification from the same magnification, it is necessary to convert the KH and lens. In the prior art, a relatively large, bulky, and heavy convex lens for forming an original image on a photoreceptor is moved in order to convert the magnification of the lens, thus making it possible to set the lens position with high precision. It was difficult to do so. Furthermore, it is difficult to set the optical length between the lens and the photoreceptor to be short, and there is a limit to the miniaturization of the copying machine.

The object of the present invention is to solve the above-mentioned technical problems.

It is an object of the present invention to provide a copying machine which can achieve magnification conversion such as equal magnification, reduction, and enlargement of a lens with high accuracy and which can be miniaturized.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a portion of an electrostatic copying machine according to an embodiment of the present invention, viewed from the front mountain side. Approximately in the center of the fuselage (not shown) is a drum 1i! 2t photoconductor on filf+
- The provided photosensitive drum 3 is rotatably mounted. Charging corona discharges that charge the photoreceptor 2 are sequentially arranged around the four sides of the photoreceptor drum 3 along the rotational direction shown by the arrow 4!
! 5. a developing device 6 that visualizes the electrostatic latent image formed on the photoconductor 2 and converts it into a toner image; a transfer corona discharger 7 for transferring the toner image formed on the photoconductor 2 to a copying machine;
8. A precise separation static eliminator that removes static electricity and separates the copy paper from the photoreceptor 2. A cleaning device 9 is disposed for cleaning the toner remaining on the photosensitive drum 3 after the transfer process.

Above the photosensitive drum 3, there is an exposure device for irradiating the image of the document onto the photosensitive member 2 between the charging corona discharger 5 and the developing device 6 via a light path 27 indicated by a two-dot chain arrow. 10 are provided. An original document mounting table 12 is provided on the upper part of the machine, on which an rt original document 1i is placed horizontally and moves back and forth as shown by an arrow. The exposure device IO includes a ninth light projecting means 13rj for irradiating light onto the original via the original placing table 12, an exposure lamp 14, a reflector 15, and a sub-reflector 16t. The light irradiated from the light projecting means 13 onto the original 11 on the original placing table 12 is irradiated onto the photoreceptor 2 through the self-hock lens 17i or 17bt- in the middle of the optical path 27, and the light is irradiated onto the original 11 on the original mounting table 12.
An image is formed on the photoreceptor 2 to form an electrostatic latent image.

The copying machine 18rjI is transported along the paper transport direction 19 and is brought into close contact with the photosensitive drum 3 facing the transfer corona discharger 7. Copy paper 1811 after the transfer process, static eliminator 8 for separation
is separated from the photosensitive drum 3 and fixed by a fixing device (not shown). FIG. 2 shows a self-hock lens 17.
FIG. 5 is a simplified perspective view of the vicinity of m and 17b. One cell-hock lens 1larj is for, for example, equal weight, and the other cell-hock lens l7Mj7'h is for, for example, reduction or enlargement. These self-hock lenses 17i, 17
bt-t, are respectively supported on both sides of a support member 20 extending in parallel over substantially the entire length of the photosensitive drum 3 above the photosensitive drum 3 . A rotating shaft 26 is provided at both ends of the support member 20 along the technique direction. a and 26b project concentrically, and these rotating shafts 36a and 26b are supported respectively by front and rear both sides of the body (not shown). A sprocket wheel 21 is fixed to one rotating shaft, for example 26m. A motor 24 is provided at a fixed position on the body (not shown), and a sprocket wheel 22 is fixed to the output shaft of this motor 24. Both sprocket wheels 21.22
An endless chain 223 is wound around the chain.

The diameter ratio of both sprocket wheels 21 and 22 is
The value is selected such that the rotating shaft 26a, that is, the supporting member 20 rotates by 180 degrees during one rotational driving operation of No.4. By doing so, the self-hock lenses 17a, 1
7bt - can be exchangeably provided in the optical path 27.

In this way, both self-hock lenses 17 are connected to the optical path 27.
Since a and 17b can be exchanged, reduced copying and enlarged copying can be achieved in a switchable manner. Moreover, 1 car cell hook lens 17m, 17br optical path 2
7, the accuracy of the exposure position can be maintained and flare light will not occur.

As another embodiment of the present invention, as shown in FIG. 3, one of the self-hock lenses 9, for example, 17a in the above-mentioned embodiment is adapted for red copying) and an ilter ratio, for example, a green filter. 30iIR may be used. Thereby, black copying and red copying can be switched freely. Note that when performing red copying, it is necessary to convert the toner to red toner.

FIG. 4 is a sectional view of another embodiment of the present invention, and FIG. 5 is a perspective view of the vicinity of the self-hock lenses 17m and 17b in FIG. 4, and corresponds to the embodiment in FIGS. 1 to 3. The same reference numerals are given to the corresponding parts. In this embodiment, support rods 32 extending substantially horizontally in the direction of the optical path 27 are provided at both ends of a support member 31 that supports the self-hock lenses 17m and 17b.
33 is fixed. These support rods 32 and 33tj are freely supported in the direction of the force by support means (not shown). Moreover, one support rod, for example 33, is provided with a rank 34, and this 1L rack is 34Kt! gear 3
5 meshes.

With this configuration, the rotational motion of the gear 35 is converted into linear motion of the support rods 32, 33C). Therefore, by rotating the gear 35 by an appropriate rotation angle by a driving means (not shown), the self-hock lens 171.
17bi can be moved almost horizontally. Therefore, both cell-hook lenses xya and t7 are placed in the middle of the optical path 27.
As another embodiment of the present invention, a filter such as the above-mentioned green filter is attached to one of the two cell-hoc lenses for 1-1 magnification, and the filter is used. It is also possible to selectively perform copying and copying without using a filter.

As described above, according to the present invention, lenses can be replaced easily and with high precision by rotating or moving the Self-Hoc lens, and by using the Self-Hock lens, the lens can be replaced easily and with high precision. Therefore, the length of the optical path between the lens and the photoreceptor can be shortened, and the size of the copying machine can therefore be reduced.

A self-hock lens located in a position away from the optical path, that is, a photoreceptor, is easily inserted into a groove, and toner and the like tend to adhere to the end lIi of the self-hock lens facing the photoreceptor. According to the present invention, since cleaning becomes easy, the photoreceptor Vcts of the self-containing lens can be kept clean at all times, making it possible to obtain clear copied images.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional If1 diagram of a portion of an electrostatic copying machine according to an embodiment of the present invention as seen from the front curved side, and FIG. 2 is a self-hock lens 17.
a, a simplified perspective view of the vicinity of 17b; FIG. 3 is a cross-sectional view of another embodiment of the present invention; FIG. 4 is a cross-sectional view of another embodiment of the present invention; and FIG. DESCRIPTION OF SYMBOLS 1... Drum 42... Photosensitive member, 3... Photosensitive drum, 11... Document, 12... Document mounting table, 17m, 1
7b... Cell hook lens, 20.31... Support 1
1.2 l. 22... Sprocket foil, 26a, 26b...
Rotation axis, 27... Light path, 30... Filter% 34
...Rack, 35...Gear agent Patent attorney Kei Nishi

Claims (1)

[Claims] A plurality of cell-hock lenses are interposed in the dark optical path between the original and the photoreceptor, and the cell-hock lenses are selectively connected to the light path II.
A copying machine characterized by being able to be placed in a third position.