JPS5919934A - Variable magnification electrostatic copying machine - Google Patents

Abstract

PURPOSE:To take a variable power copying through inexpensive constitution, by projecting light upon a copy object through a standstill optical system for desired magnfication and picking up its image when the copy object is photographed with variable magnification. CONSTITUTION:A life-size copy is taken through the rod lens 70 of the 1st standstill optical system 62 for unmagnification copying, but the 2nd standstill optical system 64 is further provided. In this 2nd standstill optical system 64, reflected light from an original irradiated with light from an original illumination lamp 66 is projected on the 1st reflecting mirror 76 through an opening 88 formed in a housing 74, reflected successively by the 2nd reflecting mirror 78, the 3rd reflecting mirror 80, an in-mirror lens 82, the 4th reflecting mirror 84, and the 5th reflecting mirror 86, and then rojected on the photoreceptor 14 of a rotating drum 1 through an opening 90 formed in the housing 74, taking a variable power copying.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electrostatic copying machines, and more particularly to variable magnification electrostatic copying machines.

In recent years, various types of variable magnification electrostatic copiers that can selectively copy originals to be copied - for example, either at the same magnification or at a predetermined magnification reduction or enlargement, have been proposed and have not been put into practical use. has been done.

However, in conventional variable magnification electrostatic copying machines,
When changing the magnification of copying, for example, (1) changing the positions of the lenses and reflecting mirrors in the optical system, (2) converting the lenses in the optical system, or (3) adding more lenses to the optical system,
There is a problem in that the mechanism for switching (moving and positioning the lens and reflecting mirror) becomes complicated and expensive.

The present invention has been made in view of this fact, and its object is to provide a variable magnification electrostatic copying machine that enables variable magnification copying with a simple and inexpensive configuration.

According to the present invention, it is possible to include a reciprocatingly movable document table having a transparent plate on which a document to be copied is placed, and the document table to be moved in a predetermined direction at a first speed. a moving means capable of moving the document at a second speed different from the first speed in a direction opposite to the predetermined direction; a first stationary optical system for projecting an image of the document as an erect image at a magnification M1 of 1; and a second static optical system for producing a copy at the first magnification M1, the original platen 11 is moved in the predetermined direction at the first speed. projecting an image of the document onto a photoreceptor through a first static optical system;
When producing a copy at the second magnification M2, the document table is moved in the predetermined direction and moved in the opposite direction at the second speed, and the document is passed through the second stationary optical system. A variable magnification electrostatic copying machine is provided, which is characterized in that it projects an image onto the photoreceptor.

Hereinafter, preferred embodiments of a variable magnification electrostatic copying machine constructed according to the present invention will be described with reference to the accompanying drawings.

First, with reference to FIG. 1, the overall structure of a variable 1g rate electrostatic copying machine constructed according to the present invention will be described. The variable magnification electrostatic copying machine, generally indicated by the numeral 2, includes a substantially rectangular copying machine housing 4.

A transparent plate 6 on which a document to be copied is placed is disposed on the upper surface of the copying machine housing 4. As shown in FIG.

This transparent plate 6 is connected to a document mounting table 8 mounted on the upper surface of the copying machine housing 4 so as to be movable in the left and right directions in FIG.
(See also FIG. 6), and as will be explained in detail later, when the copying process is performed, the position shown in FIG. It is moved between the positions by a moving means. Original table 8
Further, a transparent plate 6 and a flexible original cover plate 1° which can be opened and closed for covering the original to be copied placed on the transparent plate 6 are attached.

A cylindrical (shaped) rotary drum 12 that constitutes a support base for a photoreceptor is rotatably mounted approximately in the center of the copying machine housing 4, and at least a portion of the circumferential surface of the rotary drum 12 is provided with an electrostatic copying photosensitive material. In place of the rotating drum 12, an endless belt-like element, well known to those skilled in the art, is used, and an electrostatographic photoreceptor is disposed on at least a portion of the surface of such an endless belt-like element. You can also.

Around the rotating drum 12, which is rotationally driven in the direction shown by an arrow 16, there are a charging corona discharger 18, a developing device 20, and so on, sequentially in the direction of rotation. A transfer corona discharger 22, a charge removal corona discharger 24, and a charge removal lamp 26 are provided. The charging corona discharger 18 substantially uniformly charges the photoreceptor 14 to a particular polarity. An exposure area 28 exists between the charging corona discharger 18 and the developing device 20, and in this exposure area 28, the original on the transparent plate 6 is projected by an optical system, which will be described later and is generally designated by the number 30. An electrostatic latent image is formed on the photoreceptor 14. The developing device 20 itself may be of any well-known and appropriate form.
Toner particles are applied to the electrostatic latent image formed on 4 to develop the electrostatic latent image into a toner image. The transfer corona discharger 22 is
A corona discharge is applied to the back side of the copy paper that is brought into contact with the surface of the photoreceptor 14 in the transfer area 32, and the toner image on the photoreceptor 14 is transferred onto the copy paper. The static elimination corona discharger 24 applies corona discharge to the surface of the photoreceptor 140 after transfer, and the static elimination lamp 26 applies corona discharge to the surface of the photoreceptor 140 after the static elimination corona discharger 24 has applied corona discharge. The residual charge on the photoreceptor 14 is removed by the static-eliminating corona discharger 24 and the static-eliminating lamp 26.

At the bottom of the copying machine housing 4, there is a copy paper supply mechanism, generally indicated by the number 34, and a copy paper feeding mechanism for conveying the copy paper fed from the copy paper supply mechanism 34 through the transfer area 32.
A paper transport mechanism, generally indicated by the numeral 36, is provided. The illustrated copy paper supply mechanism 34 is well known in itself and includes a copy paper cassette 38 and a feed roller 40, which are detachably attached to the copier housing 4. The feed roller 40 is selectively driven to rotate in the direction indicated by an arrow 42, and passes through the copy paper conveying mechanism one by one to transport a plurality of stacked sheets of copy paper P stored in the copy paper top 38. 36. The illustrated copy paper transport mechanism 36 includes a pair of transport rollers 44 for receiving the copy paper P fed from the copy paper supply mechanism 34 and transporting it to the transfer area 32, a guide plate 46,
Copy paper P brought into contact with photoreceptor 14 in transfer area 32
A peeling roller 48 that peels off the copy paper P from the photoreceptor 14, a roller 50 that carries out the copy paper P from the transfer area 32, a guide plate 52, a pair of fixing rollers 54, a pair of guide plates 56, and the copy paper P to the outside of the duplex machine housing 4. It includes a pair of carry-out rollers 58 for discharging and a receiving tray 60 for receiving the copy paper P carried out from the pair of carry-out rollers 58. One roller of the pair of fixing rollers 54, the roller located at the top in the figure, is equipped with a heating element 61 such as a heater inside, and heats the surface of the copy paper P having the toner image transferred from the photoreceptor 14. Pressure and heat are applied, thus fixing the toner image to the copy paper. This roller is further provided with a peeling guide member (not shown) that peels the copy paper P from its surface and guides it downstream.

Next, with reference to FIGS. 1 to 4, the optical system 30 for projecting a document placed on the transparent plate 6 onto the photoreceptor 14 for slit exposure will be described. The optical system 30 of the variable magnification electrostatic copying machine 2 constructed according to the present invention includes a first stationary optical system 62 disposed above the rotating drum 12 and a second stationary optical system 62 disposed above the rotating drum 12 to the right. static optical system 6
4. It includes an original illumination rung 66 and a reflector plate 68 for illuminating the original placed on the transparent plate 6. In the illustrated example, the first stationary optical system 62 is arranged in the width direction (in the direction perpendicular to the plane of the paper in FIGS. 1 and 2) and has a number of rod-shaped lenses 70 (such rod-shaped lenses include, for example, This rod-shaped lens 70 is made up of
It is mounted between a front wall 72a and a rear wall 72b (see FIG. 4) which are arranged at a predetermined interval in the front-rear direction (direction perpendicular to the plane of the paper in FIG. 1) in the copying machine housing 4. Therefore, the first static optical system 62 converts the image of the document placed on the transparent plate 6 into an erect image at a first magnification M1 (equal magnification in the specific example). The image is projected onto the photoreceptor 14 of the rotating drum 12 in FIG.

The second static optical system 64 includes a nozzle 74 . This housing 74 is removably attached to the copying machine housing 4, and can be removed from the copying machine housing 4 if necessary. Note that when this second static optical system 64 is removed, the illustrated variable magnification electrostatic copying machine 2 has only the @1 static optical system 62 as an optical system, and the rod-shaped lens 70 makes a same-magnification copy. only possible.

In the housing 74, in a specific example, a first reflecting mirror 7 is provided for projecting reflected light from the original onto the photoreceptor 14.
6, a second reflecting mirror 78, a 30th reflecting mirror 80, an in-mirror lens 82, a fourth reflecting mirror 84, and a fifth reflecting mirror 86 are provided. Therefore, in the second static optical system 64, the reflected light from the original illuminated from the original illumination lamp 66 is
The light is projected onto the first reflecting mirror 76 through the opening 88 formed in the /1 housing 74, the second reflecting mirror 78, the third reflecting mirror 80, the in-mirror lens 82, the fourth reflecting mirror 84, and the third reflecting mirror 80. After being sequentially reflected by the reflecting mirrors 86 of No. 5, it is projected onto the photoreceptor 14 of the rotating drum 12 through an opening 90 formed in the housing 74. Opening 88 in housing 74
As shown in FIGS. 2 to 4, the first reflection #! A slit exposure width regulating member 92 that regulates the slit exposure width (width in the moving direction of the photoreceptor 14) of the optical path leading to the photoreceptor 76 is slidably disposed. The slit exposure width regulating member 92 can be adjusted by loosening the fixing screw 94.
It can be slid along the upper surface of the housing 74 in the width direction, ie, in the lower left direction or the upper right direction in FIGS. 2 and 3. The second static optical system 64 converts the image of the document placed on the transparent plate 6 into a second magnification M2 different from the first magnification M1 (in the specific example, M2=0).
．． Area 2 of exposure area 28 as an inverted image with -7x reduction magnification
Photoreceptor 1 of rotating drum 12 in 8b (see FIG. 2)
Project onto 4.

The first static optical system 62 and the second static optical system 64
A light shielding plate 96 is further provided between the two. The light shielding plate 96 includes a shaft member 98 and a plate member 100 fixed to the shaft member 98, and a notch 102 (see FIGS. 3 and 4) is formed at the tip of the plate member 100. . The shaft member 98 of this light shielding plate 96 is attached to the front wall 72.
& is rotatably mounted between the rear side wall 72b, and one end thereof is further rearward from the rear side wall 72b (@left side in Figure 4).
It extends to A gear 104 is fixed to one end of this shaft member 98, as shown in FIG. On the other hand, a gear 106 that meshes with the gear 104 is rotatably mounted on the back surface of the rear wall 72b. A pin 108 is fixed to the end surface of this gear 106, and this pin 108
is inserted into a long hole 112 formed at one end of an L-shaped lever member 110 rotatably mounted on the rear wall 72b. The other end of the lever member 110 is connected to the rear side wall 72.
It is rotatably connected to an output end 116 of an electromagnetic solenoid 114 fixed to b. Further, a spring member 118 is disposed between the lever member 110 and the rear wall 72b. Therefore, when producing a copy with the first magnification M1, the lever member 110 is moved by the action of the spring member 118.
The lower end of the is still in contact with the abutting bottle 117 and is held in the state shown by the solid line in FIG. ), and when producing a copy with a second magnification M2, the electromagnetic solenoid ]14 is energized;
The light shielding plate 96 is held in the state shown by the two-dot chain line in FIG. and is located at the position shown in FIGS. 3 and 4). Light shielding plate 96
is positioned in the first position, the grate member 100
completely covers the opening 88 formed in the housing 74;
The image of the document, that is, the light, is prevented from being projected onto the photoreceptor 14 through the second static optical system 64 over substantially the entire width of the second static optical system 64, and the light shielding plate 96 When positioned at the position, the tip of the great member 100 covers the upper surface of the rod-shaped lens 70, and the plate member 100
Only the light that passes through the notch 102 formed at the tip of the rod-shaped lens 70 is projected onto the photoreceptor 14 . Note that the tip of the plate member 100 covers the upper surface of the rod-shaped lens 70 in a width direction area that substantially corresponds to the width direction area where the image of the original is projected onto the photoreceptor 14 through the second static optical system 64. , prevents light from being projected through the rod-shaped lens 70 only in this width direction region, and in other width direction regions, the cutout portion 102
Light is projected onto the photoreceptor 14 through the photoreceptor 14 .

In the illustrated variable magnification electrostatic copying machine, the rotating drum 12
always moves arrow 1 at a predetermined speed regardless of the copying magnification.
It is rotationally driven in the direction shown by 6.

Further, the copy paper transport mechanism 36 also moves all the way across the transfer area 32 at a predetermined speed regardless of the copying magnification, that is, at substantially the same speed as the moving speed of the photoreceptor 14 disposed on the circumferential surface of the rotating drum 12. The copy paper P is conveyed through. On the contrary,
When the document table 8 having the transparent plate 6 is moved in the direction indicated by an arrow 120 by a moving means to be described later, it moves at a first speed (i times the moving speed of the photoreceptor 14, and
In the specific example, when the photoreceptor 14 is moved at a speed that is substantially the same as the moving speed of the photoreceptor 14, and is moved in the direction shown by an arrow 122 opposite to the direction shown by the arrow 120, the second speed (first movement speed) The moving speed of the photoreceptor 14 is 1/M2 times the moving speed of the photoreceptor 14).

Next, referring to FIG. 6, a moving means for moving the original table 8 will be explained.

In FIG. 6, which schematically illustrates the moving means, sprocket wheels 124a and 12 are arranged at a predetermined interval on the back side of a rear side wall 72b disposed in the copying machine housing 4.
4b is pivotally supported, and an endless transmission member 126 such as a chain is connected between the sprocket wheels 124a and 124b.
is wrapped around it.

An engagement protrusion 128 is fixed to this transmission member 126 . A long hole 130 is provided approximately at the center of the side edge of the document placement table 8.
A movable member 132 formed with is fixed, and a long hole 13 with is fixed.
The engaging protrusion 128 is slidably engaged in the inside of the engaging protrusion 128. Therefore, when the engagement protrusion 128 of the transmission member 126 moves in the direction of the arrow 120, the original table 8 is moved together with the retention protrusion 128 in the direction of the arrow 120, and the engagement protrusion 128 moves in the direction of the arrow 120. When moving in the direction shown in FIG.
6 from the lower tension portion 126a to the upper tension portion 126b (or from the upper tension portion 126b of the transmission member 126 to the lower tension portion R1
1126a), this engagement protrusion 128 moves inside the elongated hole 130 of the moving member 132 from the bottom to the top (1111a).
(or slide from top to bottom).

The sprocket wheel 124a is coupled to a manual drive motor such as an electric motor through a clutch means C1, such as an electromagnetic clutch, and the sprocket wheel 124b is connected to a drive means such as a manual DMK, such as an electric motor, through a clutch means C2, such as an electromagnetic clutch. DMK: Drive-coupled.

Therefore, in the illustrated moving means, the clutch means C,
When actuated, the drive means DM and the sprocket wheel 1
24a is drivingly connected to the sprocket wheel 124a.
is rotationally driven at a first speed in the direction indicated by arrow 134;
When the original table 8 is moved at the first speed and the clutch means C2 is actuated, the drive means DM and the Sugerocket wheel 124b are drivingly connected, and the Sugerocket wheel 124b is moved at the second speed in the direction indicated by the arrow 136. The document mounting table 8 is rotated and moved at a second speed.

Around the transmission member 126, as shown in FIG.
At the outer end of the second switch means S2, the transmission member 126
A third switch means S5 is located approximately in the middle of the upper tension portion 126b, and a fourth switch means S5 is located at the outer end of the Sugerocket wheel 124a.
switch means S11 are respectively provided. These switch means S 1 +82.85 and the shaft are of a known construction per se, and control the movement of the original table 8.

Note that the first switch means S1 is arranged so that the original table 8 is in the direction of the arrow 12.
The third switch means S5 is turned on (closed) only when the original table 8 moves in the direction of the arrow 120.

In the illustrated variable magnification electrostatic copying machine 2, when placing an original on the transparent plate 6 of the original placing table 8, as is easily understood from the above description, as shown in FIG. 1
When producing a copy with a magnification M1 of
As shown in A (or On), the original is placed on the transparent plate 6, and when producing a copy with the second magnification M2, the left end and rear end (the upper end in FIG. 6) of the transparent plate 6 are The document is placed on the transparent plate 6 as shown by the two-dot chain line 0'A (or O'n) as a reference.

A control panel 138 (see FIG. 7) is further provided on the upper surface of the copying machine housing 4 of the variable magnification electrostatic copying machine 2 described above. Switch DS, magnification conversion switch VS
ji Light amount adjustment one EC.

A copy number setting counter PC and a print button PB are provided.

Next, the effects of the variable magnification electrostatic copying machine 2 having the above-mentioned general configuration will be explained.

If you want a copy with the first magnification M1, first turn on (close) the main switch SW and check whether the magnification conversion switch S is in the state of the first magnification M1. When the switch VS is in the state of the second magnification M2, the magnification conversion switch vs f is switched to change from the state of the second magnification M2 to the state of the first magnification M1. As a result, the operation of the electromagnetic lens 114 is stopped and the light shielding element 96 is positioned at the first position (the position shown by the two-dot chain line 96A in FIG. 2 and the solid line in FIG. 5), and
As will be described in detail later, the original table 8 is moved to a position above the photocopying machine 4 (indicated by a solid line in FIG. 1).
is located at the first stop position (the position where the retaining protrusion 128 is located approximately in the middle of the lower tension portion 126a of the transmission member 126, as shown by the solid line in FIG. 6), and thus the first The copy of the copy with the magnification M1 becomes ready for copying.

].

Next, press the print button PB. As a result, the clutch means C2 is actuated, and the driving means DM and the tin rocket wheel 124b are drivingly connected via the clutch means C2, and the document table 8 is moved to the position shown by the solid line in FIG. 1 in the direction shown by the arrow 122. from.

It is moved at the second speed to the position indicated by the two-dot chain line 8B (the exposure preparation process is performed). When the document mounting table 8 reaches the position indicated by the two-dot chain line 8B in the figure (therefore, the engaging protrusion 128 is located at the outer end of the sprocket wheel 124b) (the exposure preparation process is completed). , the moving member 132 of the original table 8 switches the second switch means S2 to O.
N (closed), the operation of the clutch means C2 is stopped, and at the same time the clutch means C1 is activated. Clutch means C1
is actuated, the drive means D is activated via the clutch means C1.
M and the tin rocket wheel 124a are drivingly connected, and the document mounting table 8 is moved from the position shown by the two-dot chain line 8B to the first position shown by the two-dot chain line 8A in FIG.
is moved at a speed of At this time, an appropriate switch means (
For example, the document illumination lamp 66 is turned on by the second switch means S2), and the document is irradiated while the document table 8 is moved at the first speed, so that the image of the document is formed in radial lines or in circles. 70, therefore, it is projected as an erect image with a first magnification M1 onto the photoreceptor 14, which is moved at a predetermined speed, through the first static optical system 62 (an exposure process is performed). Note that when producing a copy with the first magnification M1, the light shielding plate 96 is placed in the first position (in FIG.
The second stationary optical system 64 is positioned in the position shown at A and shown in solid lines in FIG.
The image of the document, that is, the light, is prevented from being projected onto the photoreceptor 14 through the photoreceptor 14. Further, during the exposure process, the moving member 132 turns on (closes) the third switch means S5, but when producing a copy with the first magnification, the third switch means S5 is simply turned on (closed). There is no operation controlled by this third switch means S5. The original table '8 reaches the position K shown by the two-dot chain line 8A in FIG. 1 (therefore, the position where the engaging protrusion 128 is located at the outer end of the Sugerocket wheel 124a) (the exposure process is completed). , the moving member 132 of the document placement table 8 moves to the fourth position f.
Turn on (close) the means SII and turn on the document illumination lamp 66.
is turned off, the operation of the clutch means c1 is stopped, and the clutch means C2 is activated.

When the clutch means C2 is actuated, the driving means DM and the sprocket wheel 124b are drivingly connected via the clutch means C2, as described above, and the original table 8 is moved in the direction indicated by the arrow 12.
It is moved at a second speed in the direction shown by 2 from the position shown by the two-dot chain line 8A to the position shown by the solid line in FIG. 1 (the return stroke is performed). 1 and 6.
When the moving member 132 reaches the position indicated by the solid line in the figure, the moving member 132 turns on (closes) the first switch means 81, and the operation of the clutch means C2 is stopped.
(The return stroke is completed.)

On the other hand, the electrostatic latent image formed on the photoreceptor 14 by projecting the image of the document onto the photoreceptor 14 through the first static optical system 62 is developed into a toner image by the developing device 20. In the transfer area 32, this toner image is transferred to the covering paper P.
The transferred toner image is fixed onto the copy paper P by the pair of fixing rollers 54, and then the copy paper P is discharged from the copy machine housing 4. In this way, a copy of the first magnification M1 (in the specific example, the same size) is generated by the first stationary optical system 62.

If a copy with a second magnification M2 is desired, the above-mentioned first
, the magnification conversion switch VS is switched from the state of the first magnification of 4M1 to the state of the second magnification of M2.
is excited and the light shielding plate 96 is in the second position (solid line in FIG. 2,
The position shown by the two-dot chain line in Figure 5, and the position shown in Figure 3 and 4
At the same time, the clutch means C2 is actuated, and the driving means DM and the sprocket wheel 124b are drivingly connected via the clutch means C2, and the document placing table 8 is moved in the direction shown by the arrow 122. It is moved at the second speed from the position shown by the solid line in the figure to the position shown by the two-dot chain line 8B. When the document placing table 8 reaches the position shown by the double-dot lead line 8B in FIG. turns on (closes) the second switch means s2, the operation of the clutch means C2 is stopped, and the clutch means C1 is activated. When the clutch means C1 is actuated, the drive means DM and the sprocket wheel 124a are drivingly connected via the clutch means C1, and the original table 8 is moved in the predetermined direction indicated by the arrow 120 tA.
It is moved at the first speed from the position shown by the two-dot chain line 8B in Figure i1 to the position shown by the solid line. Then, the original placing table 8 is placed on the first
When the moving member 132 reaches the position indicated by the solid line in the figures and FIG. The second stop position If is located at the upper position (indicated by a solid line in FIG. 1). It is positioned approximately in the middle (#), and thus becomes ready to copy a copy of K20 magnification M2.

Next, in the state shown in step 1, the print button PR is pressed. As a result, the clutch means ci is actuated, and as described above, the first document placement table 8 is moved from the position shown by the solid line in FIGS. (The exposure preparation process is performed.) The document mounting table 8 reaches the position shown by the inclined double-dotted line 8A in FIG. ), the moving member 132 of the document table 8 turns on (closes) the fourth switch means sII, the operation Nb of the clutch means c1 is stopped, and the clutch means C2 is activated. When the clutch means C2 is actuated, as described above, the document placing table 8 is moved at the second speed in the direction shown by the arrow 122 from the position shown by the double-dot chain 118A in FIG. be moved. At this time, an appropriate switch means (for example, the fourth switch means 51
1), the original illumination simulator 6 is turned on, and the original is irradiated while the original placing table 8 is moved at the speed of @2, and the image of the original is reflected by the first reflecting mirror 76 and the second reflecting mirror 76. , the third reflecting mirror 80 , the in-mirror lens 82 , the fourth reflecting mirror 84 , and the fifth reflecting mirror 86 , and thus the second static optical system 64 to form an inverted image with a second magnification M2. (an exposure process is performed) onto the photoreceptor 14 which is being moved at a speed of Note that the second magnification M2
When producing a copy of ) and covers the upper surface of the rod-shaped lens 7o in a width direction area that substantially corresponds to the width direction area where the image of the document is projected onto the photoreceptor 14 through the second static optical system 64.
Only in this width direction region, the image of the document, that is, light, is prevented from being projected onto the photoreceptor 14 through the entire first static optical system 62, and in other than the width direction region, the notch 102 of the light shielding plate 96 The light is then projected onto the photoreceptor 14 through the first static optical system 62 . Therefore, during the exposure process, the second
The static charge applied to an area other than the width direction area where the image of the original is projected onto the photoreceptor 14 through the static optical system 64 of the original illumination lamp 66 is exposed to light from the original illumination lamp 66 through the entire first static optical system 62. It is effectively removed by the light projected onto the body 14. Further, during the exposure process, the moving unit 132 turns on (closes) the first switch means S1, but the second magnification M
When producing a copy of No. 2, the first switch Sl is simply turned on (closed) and this first switch means S
Nothing is controlled by l. When the document mounting table 8 reaches the position shown by the two-dot chain line 8B in FIG. 1 (therefore, the position where the engaging protrusion 128 is located at the outer end of the sprocket wheel 124b) (the exposure process is completed),
The movable portion 132 of the document placement table 8 is the second switch means S.
2 is turned on (closed), the document illumination lamp 66 is turned off,
The operation of the clutch means C2 is stopped and the clutch means C1 is activated. When the clutch means C1 is actuated, as described above, the document table 8 is moved at the first speed in the predetermined direction shown by the arrow 120 from the position shown by the two-dot chain line 8B in FIG. 1 to the position shown by the solid line. (The return process is performed.) When the document table 8 reaches the position shown by the solid line in FIGS.
operation is stopped, and the document mounting table 8 is held at the second stop position (the position where the engagement protrusion 128 is positioned approximately at the center of the upper tension portion 126b) (the return stroke is completed). finish.).

On the other hand, the electrostatic latent image formed on the photoreceptor 14 by projecting the image of the document onto the photoreceptor 14 through the second static optical system 64 is developed into a toner image, as described above.
This toner image is transferred onto copy paper P, and after the transferred toner image is fixed on copy paper P, it is discharged from the copy machine housing 4 as a copy. Thus, the second magnification M2 (in the specific example, M2
=0.7 times) copies are generated.

In order to change the copyable state with the second magnification M2 to the copyable state with the first magnification M1, in the copyable state with the second magnification M2, the magnification conversion switch VS is set to the second magnification converting switch VS.
The state of the first magnification M2 is switched to the state of the first magnification M1. As a result, the operation of the electromagnetic solenoid 114 is stopped, the light shielding plate 96 is positioned at the first position (the position shown by two points d#96A in FIG. 2, and the solid line in FIG. 5), and the clutch means C1 is actuated, and as described above, the document mounting table 8 is moved at the first speed in the predetermined direction shown by the arrow 120 from the position shown by the solid line in FIG. 1 to the position shown by the two-dot tin line 8A. The document placement table 8 is indicated by the two-dot chain line 8A in FIG.
When reaching the position indicated by (therefore, the position where the engagement protrusion 128 is located at the outer end of the sprocket wheel 124a), the moving member 132 switches the fourth switch means SII to O.
N (closed), the operation of the clutch means C1 is stopped and the clutch means C2 is activated. Clutch means C2
When is activated, the original table 8 moves in the direction of arrow 1, as described above.
It is moved at a second speed in the direction indicated by 22 from the position indicated by the two-dot chain line 8A in FIG. 1 to the position indicated by the solid line. Then, when the original table 8 reaches the position shown by the solid line in FIGS. 1 and 6, the moving member 132 turns the first switch means S1 into the
N (closed), the operation of the clutch means C2 is stopped, and the document placing table is placed on the eight copy machine housing 4 (as shown by the solid line in FIG. 1).

) at the first stop position (the retaining protrusion 128 is located at the lower tension portion 126a of the transmission member 126, as shown by the solid line in FIG.
2), and is thus in a state in which it is possible to copy a copy at the first copy magnification M1.

In this specific example, as can be easily understood from the above description, in a known electrostatic copying machine having a document table mounted reciprocally on the copying machine housing, the document table is By effectively utilizing the movement speed of the return stroke (as copying speeds have increased, the movement speed of the return stroke is generally faster than that of the exposure stroke), a separate driving means can be used. Copying with a variable magnification (reduction magnification) becomes possible without making any major changes such as providing a device (including means for changing the moving speed of the document table).

Although preferred specific examples of the variable magnification electrostatic copying machine constructed according to the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to such specific examples, and does not depart from the scope of the present invention. Various modifications and modifications can be made without any problems.

For example, in the illustrated example, the first static optical system is composed of a Rondo lens, and the second static optical system is composed of a combination of an in-mirror lens and five reflecting mirrors.
The first static optical system and the static optical system @2 are not limited to the forms shown in the figures; 2
The static optical system may be any type of optical system that projects an inverted image onto the photoreceptor.

In addition, in the illustrated example, the exposure area on the photoconductor by the first static optical system and the exposure area on the photoconductor by the second static optical system are different, but these exposure areas are It can also be done. In such a case, if the timing of starting supply of copy paper is controlled by the rotation of a rotating drum, the timing of starting supply of copy paper will always be constant regardless of the copying magnification. be able to.

In addition, in the illustrated example, when copying at the first magnification M1 and when copying at the second magnification M2, the document table is moved at a first speed when moved in a predetermined direction;
When moved in the opposite direction to the predetermined direction, it is moved at the second speed.
It is also possible to always reciprocate at the first speed when copying with the first magnification M1, and always reciprocate at the second speed when copying with the second magnification M2.

In addition, in the illustrated example, the original table is configured to always move in a fixed direction, but in some cases, the original table is moved to the first position when copying at the second magnification M2.
The direction of movement during copying with the magnification M1 can also be K rather than being moved in the completely opposite direction.

In addition, in the specific example shown, it is possible to copy at the same magnification using the first static optical system and at a reduction (0.7x) using the second static optical system, but copying is limited to the same magnification and reduction. For example, the present invention can also be applied to an equal magnification ring using the first static optical system and an enlarged ring using the second static optical system.

Furthermore, in the illustrated example, the variable magnification electrostatic copying machine uses a so-called toner image transfer type copying machine that forms a toner image on a photoreceptor disposed on a rotating drum and then transfers it to copy paper. However, the present invention is applicable not only to such a toner image transfer type electrostatic copying machine, but also to (1) forming an NT latent image on a photoreceptor disposed on a support member such as a rotating drum; After this electrostatic latent image is transferred to copy paper, the electrostatic m-image on the copy paper is developed (so-called 1!). [Latent image transfer type electrostatic copying machine, (2) After forming an electrostatic latent image directly on the photoreceptor coated on the copy paper! ? It can also be applied to a so-called direct copying machine that develops an IvL latent image.

[Brief explanation of the drawing]

FIG. 1 shows a variable magnification rfj constructed in accordance with the present invention.
FIG. 2 is a sectional view illustrating a preferred example of the fK copying machine. FIG. 2 is an enlarged sectional view showing a main part of the optical system of the variable magnification electrostatic copying machine shown in FIG. 1. FIG. 3 is a perspective view showing essential parts of the optical system shown in FIG. 2. FIG. 4 is a plan view showing essential parts of the optical system shown in FIG. 2. FIG. 5 is an explanatory view of the operation for explaining the construction of the amber plate of the optical system shown in FIG. 2. 6 is a schematic diagram showing a moving means for the variable magnification electrostatic copying machine shown in FIG. 1. FIG. 7 is a plan view showing the variable magnification electrostatic copying machine shown in FIG. 2...Variable magnification electrostatic copying machine 4...Copying machine housing 6...Transparent plate 8...Document mounting table 12...Rotating drum 14...Electrostatic photoreceptor 30...Optical system 62... First stationary optical system 64... Second stationary optical system 12r4 A and 124b... Sprocket wheel 126... Transmission members C1 and C2... Clutch means DM... Drive means

Claims (1)

[Scope of Claims] 1. A document placement table that is reciprocatably mounted and has a transparent plate on which a document to be copied is placed, and the document placement table is moved in a predetermined direction at a first speed. and a second speed different from the first speed in the opposite direction to the predetermined direction.
a moving means capable of moving at a speed of;
a first static optical system for projecting an image of the document as an erect image at a magnification M1 of M1; and a second static optical system, and when producing a copy at the first magnification M1, move the original table in the predetermined direction at the first speed and When projecting an image of the original onto the photoreceptor through a static optical system to generate a copy at the second magnification M2, move the original placing table to the second magnification in a direction opposite to the predetermined direction. A variable magnification electrostatic copying machine characterized in that the image of the document is projected onto the photoreceptor through the second stationary optical system by moving at a speed of . 2. The first magnification M1 is substantially 1, the second magnification M2 is less than 1, the first speed is substantially the same as the moving speed of the photoreceptor, and the second 2. The variable magnification electrostatic copying machine according to claim 1, wherein the speed is 1/M2 times the moving speed of the photoreceptor. 3. The variable magnification electrostatic camera according to claim 2, wherein the first static optical system includes a large number of rod-shaped lenses arranged in the width direction. 4. The variable magnification electrostatic copying machine according to claim 2 or 3, wherein the second static optical system includes one in-mirror lens and a plurality of reflecting mirrors. 5. When producing a copy at the first magnification M1, the first
a light-shielding plate positioned at a second position when producing a copy at the second magnification M2, the light-shielding plate being positioned at the first position (= When the second stationary optical system is turned off, the second
prevents light from being projected onto the photoreceptor through a static optical system, and when positioned in the second position, an image of the document is projected onto the photoreceptor through the second static optical system. Claims 1 to 4 of the scope of patent iiv, which prevent light from being projected onto the photoreceptor through the nineteenth stationary optical system only in a width direction area that substantially corresponds to the width direction area to be projected. The variable magnification electrostatic copying machine according to any one of the above.