JPS5840518A - Optical device having variable magnification - Google Patents

Abstract

PURPOSE:To obtain an image with a focused magnification by compensating the lens and mirror positions corresponding to a selected magnification in accordance with a focal distance error of a lens. CONSTITUTION:A pin 57 fixed on a mirror board 21 provided with mirros 14, 15 and a pin 49 fixed on the end of a lod 47 for a stopper 38 engaged with the notches 36, 37 of a positioning plate 35 are engaged with the fluted cams 58, 51 of a cam plate 50 respectively. When the cam plate 50 is rotated by a motor 52, a mirror board 21 and a positioning plate 35 for a lens 16 are moved along a rail 23 respectively. In said device, the moving distance of the mirror board 21 and the positioning plate 35 can be compensated in accordance with the focal distance error of each lens by loosening a nat 54 to control the rotation of the cam plate 50 around an axis 53. In any magnification mode, a focused image with the magnification corresponding the selected mode can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable magnification optical device that can selectively form an original image on a photosensitive surface at different magnifications, such as a high-magnification copying machine. When doing so, the ratio of the optical path length between the document and the lens and the optical path length between the lens and the photosensitive surface is changed in accordance with the selected magnification.The position of the lens is then selected to change this optical path length ratio. Generally, it is changed according to the magnification.

Incidentally, the focal length of an actual lens usually differs from the designed value due to various factors at the time of manufacture. In other words, the actual focal length of the lens includes an error with respect to the design value. Therefore, by correcting the mirror position and the lens position during 1-magnification image formation, the entire optical path between the original and the photosensitive surface is adjusted. The length and the optical path length ratio are corrected in accordance with the focal length error of the lens, so that a focused 1-magnification image is formed on the photosensitive surface. However, if the mirror or lens is then moved by the designed distance to form a reduced or enlarged image, the image on the photosensitive surface will be out of focus due to the focal length error. Therefore, in order to focus the image again, the lens position is corrected and the document surface and photosensitive surface are placed in a position where they have an optically conjugate relationship. Therefore, the magnification of the obtained image will be different from the selected magnification.

The main purpose of the present invention is to provide a variable magnification optical device that solves the above-mentioned disadvantages. Figure 1 is a schematic diagram of an optical path development for explaining one embodiment of the present invention. , in the figure, P is, for example, an electrophotographic photoreceptor. 01 indicates the optical position of the document when forming a 1-magnification image when the lens ■ has a focal length f of the design value p. indicates the optical position of the document at the time of β-fold image formation when the lens I has the above focal length f. (In the case of the figure, it is set as 0 × β × 1.

) When forming a same-magnification image, a lens with a focal length f is placed at the position Nt. At this time, the optical path length between the original position 01 and the lens position N1, and the optical path between the lens position N1 and the photoreceptor 2. Both long ores are 2f. As a result, a focused, same-size image of the document can be formed on the photoreceptor P.

Next, in order to form a β-fold image, the lens having the above focal length f is moved to the lens optical axis and brought to the N2 position.The N, position and the distance between the N2 positions are as follows. It can be expressed by the formula.

Lt, = (l-β)f t9, In order to form a β-fold image, the lens element is moved to the above-mentioned N3 position, and the mirror provided in the optical path between the lens 11 and the original is moved, etc. , set the optical position of the original to 0. In other words, the total optical path length between the original and the photoreceptor is lengthened by . It can be expressed by the following formula.

L, = engineering%.

In this way, the total optical path length is made longer than that when forming an image at the same magnification, and the optical path length between the original and the lens is changed from the original position to the N position, and the optical path length between the lens and the photoreceptor is adjusted. When the ratio of the optical path lengths is l;β and sulco), a focused β-fold image of the original document is formed on the photoreceptor P.

Now, the prefectural difference Δf (in fact, Δ
f<Otv@), in other words, a lens element whose focal length is (f+Δf)
112 when using. When the original is in focus, a 9-1 magnification image is formed.By adjusting the position of a mirror placed in the optical path, etc., the original position and the total light length between the photoreceptors are corrected, and the optical position of the original is set to 0. O N1 position, the interval ΔL1 between the N1 positions is 12Δf1, and the correction amount for the total optical path length, that is, the 01 position, the interval ΔL8Δf between the 01 positions)
It is. Through such correction, the lens I' can form a focused, same-size image of the original on the photoreceptor P.

Next, as in the conventional case, by the magnification changing operation, the lens 1' is moved by a distance LS on the optical axis A, and the mirror etc. Move the entire path length between the original and the photoreceptor,
If the length is 9, the lens is located at the position of I'[N,
This is the optical position Fi04 of the document. Therefore, in this case, the total optical path length between the original and the photoreceptor is (4(f+Δf)+L
t), the optical path length U(2(f+Δf
)0L1+L, ), and the optical path length between the lens and the photoconductor is (2(f+Δf)-Ll), so the lens ■' at the N4 position \ focuses the original on the mineral photoconductor. A β-fold image cannot be formed. Therefore, if the total optical path length is kept at (4(f + Δf) + L) and the position of the lens I' is corrected, the photoreceptor Kf
It is possible to form a focused image of a fi draft.

In addition, the optical path length between the lens and the photoreceptor is (2(f+Δf)
- Ll) (that is, hold the lens E' position and leave it as it is). Correct the position of the mirror, etc. on the object side and adjust the optical path length between the original and the lens. Even with correction, it is possible to form an in-focus original image on the photoreceptor. However, even in the case of this deviation,
The magnification of the formed original image is different from β.

Therefore, as shown in Figure 1, there is an error Δ in the focal length of the lens.
If f exists, the lens ■' is set to position N instead of position N4 in the β-magnification image forming mode, and the optical position of the original is set to position oI instead of position N4.In other words,
If there is an error Δf in the focal length of the lens, the magnification changing operation causes lens E' to move a different distance than it would if there was no error in the focal length of the lens.

In addition, in an apparatus in which the total optical path length between the document and the photoreceptor is moved by lens focal point movement, the moving distance is made to be different from that in the case where there is no error in the lens focal length).

Therefore, the amount of movement in the direction along the optical axis A when changing the magnification of a lens I' with an error of Δ10 in focal length, and the amount of movement along the optical axis A when changing the magnification of a lens I' with no error in focal length. The amount of difference ΔL1 from the amount of movement L1 for
can be expressed by the following formula.

ΔT=(β−1)Δf Nine, when there is an error Δf in the lens focal length and there is no error in the amount of change L4 of the total path jk between the original and the photoconductor and the lens focal length when changing the magnification The amount of difference ΔL from the amount of change L1 in the total optical path length between the original and the photoconductor when changing the magnification of
4 can be expressed by the following formula.Thus, the lens element with an error Δf in focal length is
When changing the magnification, change the optical position of the original from the 01 position to the 01 position by changing the distance (Ll-) from the position N, and changing the total path length between the original and the photoconductor (to -ΔL4). , ``By doing this, a focused β-fold image of the original is formed on the photoreceptor.'' Note that 1ΔLsI・, ΔL4 is Δf as follows from the above equation.
Since Δf is a function of the above ΔLs.

ΔL4 is each uniquely defined as 1, and therefore the amount of movement of the lens (Lt-ΔL1) and the amount of change in the total optical path length (Lw-Δ
La) are also uniquely determined. In other words, the correction amount of the lens movement amount and the correction amount of the total optical path length change amount correspond to each other.

Although Fig. 1 illustrates the case where Δf is negative and β is smaller than 1, the same thing can be said when Δf is positive and β is larger than 1. (C) The present invention can also be applied when Δf is positive and β is larger than l. (9) In the above, it is said that the lens is at the position approximately * -e Nl -) The principal point of the lens is Position N1-.

This is an abbreviation that means that the lens is located at N, and in good condition.Next, an example of a copying machine to which the present invention is applied will be described.Figure #I2 shows the entire copying machine. It is an explanatory diagram. The optical path development diagram of the optical system is generally shown in FIG. In the figure, P is an electrophotographic photoreceptor as described above, which is configured in a drum shape and rotates in the direction of the arrow around the shaft 4.During this rotation, the photoreceptor P is first discharged by the corona discharger L. It is then uniformly charged, then by the optical system described below)
, an optical image of document 0 at a selected magnification is projected onto photoreceptor P via slit 2 . By slit exposure of this optical image, a photoreceptor P is formed, and this wet image is then intensively imaged by a dust collector 3.During this development, the photoreceptor P is A toner image at the selected magnification is obtained.・7
Fi transfer paper is sent to the transfer position by a conveyance roller 5 in synchronization with the rotation of the drum P. At the transfer position, the paper 7 is conveyed in contact with the Fi photoreceptor P, and is subjected to the action of a corona discharger 60. As a result, the toner image of the original document is transferred onto the paper 7. After passing through the transfer position, the good paper 7 is guided to the fixing device 8, where it is transferred and the nine toner particles are fixed on the paper 7Vc. On the other hand, the toner remaining on the surface of the photoreceptor after transfer is removed by the cleaning member 9. Thereafter, the photoreceptor P is illuminated entirely with a lamp lO to remove the residual charge, and the above image processing cycle is repeated again.

Now, reference numeral 11 is a movable document table on which the document 0 to be copied is placed. The original O supported on the table 11 is illuminated by a lamp 12.The light from this original 0 is filtered by a filter 13.14.15
are sequentially reflected and incident on the imaging lens 16, and the lens 16
After being emitted, it is reflected by Mi 2-17, and then passes through the slit 2.
The light passes through the photoreceptor P and enters the photoreceptor P. Lens XZ, <t-13
, 17U is always fixed in position, and mirror 14
, 15, the lens 16 moves during the magnification changing operation,
When the optical image of the original is exposed to the photoreceptor P, it is selected and held stationary at a position corresponding to a large magnification.And when the optical image of the original is exposed to the photoreceptor P as described above, the original platen 11Fi moves in the direction of the arrow, thereby scanning the original. The moving speed of the stand 11 in the arrow direction, in other words, the scanning speed of the document 0, is changed in accordance with the selected magnification. Alternatively, the moving speed of the stand 11 is the same for any magnification, and the photoreceptor The circumferential speed of P may be selected and the history may change corresponding to a large magnification, or the relationship between both the moving speed of the platform 11 and the circumferential speed of the photoreceptor P (a magnification translated in parallel to the selected magnification) may be established. Changed so that it holds true. When the N document scans are completed, the table 11 moves back at a high speed in the direction opposite to the direction of the arrow, and returns to its forward movement starting point position.

Now, the lens 16 for forming an optical image of the original O on the photoreceptor P is held at the solid line position in the figure in the same-magnification image formation mode.
In the .beta.-fold (the case of .beta..sub.l is exemplified as in FIG. 1) high formation mode, it is held at the position 16' shown by the broken line in the figure. That is, the lens 16 is moved during the magnification changing operation in order to change the ratio of the optical path length between the document and the lens to the optical path length between the lens and the photoreceptor in accordance with the selected magnification. On the other hand, the mirrors 14 and 15, which are arranged perpendicularly to each other and direct the light from the original O to the lens, are held at the solid line position in the diagram in the 1x copying mode, and between the original and the photoconductor in the βx copying mode. In order to change the total party route length of
, 15' @ In the illustrated example, the mirror 13d forms an angle of 45° with respect to the original surface, and the mirror 14 is parallel to the mirror 13. So Mi? The optical axis A is parallel to the document surface between -13. be moved in parallel. Then, when the mirrors 14 and 15 move parallel to the original surface to the left on the distance diagram l, the total optical path length becomes longer by 2, and when they move to the right, the total optical path length becomes 21.
9 Therefore, the distance between the solid line position and the broken line position of the mirror 14.15 is / if there is no error in the lens focal length.
2 is acceptable, and if there is an error Δf in the lens focal length, L4
/2.

In other words, in the same magnification image forming mode, if there is no error in the lens focal length, the mirrors 14 and 15 will set the optical position of the document surface to 01 in Figure 1, but if there is no error in the lens focal length, If there is Δf, the optical position between the originals is 1111
Mirror 14 in the position shown in the figure. isa,
/ff1ll formation mode, if there is no difference in lens focal length by 1, the optical position of the document surface is set to the false position shown in Figure 1, and if there is an error Δf in the lens focal length, the optical position of the document surface is The position should be set to 0, not 04 in Figure 1.

Further, the distance between the solid line position and the broken line position of the lens 16 is /2 if there is no 1 difference in lens focal length, and /2 if there is an error Δf in the lens focal length. In other words, in the same-magnification image forming mode, if there is no error in the lens focal length, the lens is positioned at the position corresponding to N1 in Figure 1, and if there is an error Δf in the lens focal length, the lens is positioned at the first position. In addition, in the β-magnification image forming mode, the lens is in the position corresponding to the figure ON, and if there is no error in the lens focal length, the first
If there is an error Δf in the lens focal length, it is located at a position corresponding to N1 instead of N in Figure 1. Thus, the lens focal length includes the error Δf. However, both the original magnification image and the β magnification image can be formed on the photoreceptor with accurate magnification and in accurate focus.

As mentioned above, depending on the presence or absence of an error with respect to the design value fK of the lens focal length and the amount of error Af, not only the respective positions of the lens 16 and the mirror 14 and 15 when forming a 1-magnification image but also It also corrects them when forming a β-magnified image, and also corrects the amount of movement of each of the lens 16 and @see 14.15 when changing the magnification.The first mirror 18 is moved in a direction parallel to the document surface, in other words Then, Mi2-14.1 for changing the total optical path length.
It has a long hole 19 that is long in a direction parallel to the moving direction of 5, and a screw 20 is fitted into this long hole 19.

Screw 201d 2nd mirror 214C is screwed in,
As a result, the 1st < 2 18 is fixed to the 2nd mirror 21 ◎ Therefore, the relative position of the 1st mirror 18, and therefore the mirror 14.15, to the 2nd mirror 21 is fixed. To fix the fixed position, loosen the screw 20 and connect this screw 20 to the long hole 19.
c) By moving the mirrors 14, 15 under guidance in a direction parallel to the document surface with respect to the 1s2 eraser 21, the mirrors 14, 15 can be adjusted in this direction. As described below, #! of the mirror 14.15 above. Adjustment of the relative fixing position for each 2-mirror unit 21 is performed when the original in the same-magnification image forming mode,
This is performed in order to correct the total path length between the photoreceptors by the length of the above-mentioned ΔL in accordance with the lens focal length error Δf.

The second i-ra 21fi has a slide bearing 22, which is elongated in the direction parallel to the document surface, and is slidably fitted in the guide rail 23 in the elongated direction. There is. Accordingly, the mirrors 14 and 15 are movable in a direction parallel to the document surface, guided by the guide rail 230, together with the second roller unit 21, in order to change the total optical path length in accordance with the change in magnification.

Next, the lens 16 is fixedly held within the lens barrel 24. The lens barrel 24 is fixed to an N lens base 25Vc. This lens base 25 has a long hole 26 extending in a direction parallel to the document surface. This elongated hole 26 has a screw 2.
7 is fitted, and screw this screw 27 into the second lens stand 28.
By screwing into the second lens stand 28, the first lens stand 25, and hence the nine lenses 16, are fixed to the second lens stand 28. Now loosen the screw 27 and fix it (16 fixed 11th la, 25t screw 227 and long hole 26C)
The guide allows the camera 281 to move in a direction parallel to the document surface, thereby moving the lens table 25, and therefore the lens 16, relative to the second lens table 28 in a direction parallel to the document surface. The relative fixed position of the lens 16 can be adjusted in order to correct the position of the lens 16 in the same-magnification image forming mode by the distance Δh- corresponding to the lens focal length error Δf. It is something.

A sliding bearing 29 is fixed to the second lens stand 28, and this bearing 29 is fitted to be movable in the longitudinal direction of the guide shaft 23, which is fixed to a fixed member such as a beam inside the main body of the copying machine. This shaft 230 is guided by
is movable integrally with the second lens stand 28 in a direction parallel to the document surface in order to change the optical path length ratio as the magnification changes.

The second lens stand 28 is provided with a wire loosening prevention spring 31i.
The wire 30 is connected through the wire 30 (the wire 31 is connected to the wire 30 and the stand 28 in a state that is more tensioned than normal). 732 and 33, and the pulley 32 is connected to the output shaft of a reversible motor 34. When the motor 34 is rotated in the forward direction, the pulley 32 rotates in the opposite direction, and the lens 16 is rotated. The fixed second lens stand 28F1 moves to the right in the figure along the optical axis,
When the motor 34 is reversed, the pulley 32 rotates in the direction of the hour hand, and the second lens stand 28 moves to the left in the figure along the optical axis ^.

A positioning plate 35 is fixed to the second lens stand 28. The plate 35 is provided with cutouts 36 and 37. Is the spacing between the notches 36 and 37 WI in Figure 1? , and the length of L1 is quite large. Therefore, in the same-magnification image forming mode, the stopper 38 engages with the notch 36, and in the β-magnification image forming mode, the stopper 38 engages with the notch 37. By aligning them, the lenses 16 are fixed and the nine N2 lens bases 28 are kept stationary. ζIf the stopper 38 is configured to move in and out of the notches 36 and 37 at the same position, the lens 16d will only move the distance L1 in the optical axis A direction. In the configuration, the lens 16 has a focal length fi of the design value p.
If so, a focused and accurately magnified image will be displayed on the photoreceptor P in both the 1-magnification image formation mode and the β-magnification image formation mode.
However, if the focal length of the lens 16 has an error Δf with respect to the design value f, the lens 16Fi will be stopped at the N4 position in FIG. 1 in the reduction copying mode. Therefore, a focused and accurately 1x original image will not be formed on the photoreceptor.

For this purpose, the device shown in Fig. 3 has been devised as follows.

In other words, a long hole 39 is provided at the base of the b1 stopper 38 in a direction parallel to the longitudinal direction of the guide rail 23.
A bottle 40 is loosely fitted into this elongated hole. bottle 40
The same kind is attached to the pin stand 42 fixed to the tip of the '41O.

The other end of the V-shaped opening 41 is connected to an electromagnetic plunger 43.The rod 41 is guided and supported by a sliding bearing 48 that is positioned at a fixed position so as to be movable in the longitudinal direction of the rod. A compression spring 44 is interposed between the nine pin stand 42 and the plunger 430, and the spring 44 projects into the notch 36, 37 of the stopper ast-1 through the pin 40 of the pin stand 42. As shown in FIG.
This granger 43 resists the elastic force of the spring 44 and
By pulling the door 41, the stopper 38 is retracted from the notch 36, 37 and brought to a position where the second lens stand 28 is free to move.

The stopper 38 is fixed to the tip of a rod 47 that is inserted into the stopper insertion hole of the stopper guide member 45 so as to be movable in directions perpendicular to the longitudinal direction of the guide rail 23 and supported so as to be movable in a direction parallel to the longitudinal direction. ing. When this rod 47 is moved in a direction parallel to the longitudinal direction of the guide rail 23C, the stopper 38 supported by the guide member 45 also moves in the same direction.

Since the stopper 38 is connected to the bin 40 through the elongated hole 39, the bin 40 does not prevent the above-mentioned movement of the stopper bar 38, and the stopper 38 moves in the above-mentioned direction with respect to the bin 40. - A pin stand 48 is fixed to the other end of the rod 47.
A pin 49 of the same kind is attached to the pin base 48 of the pin 48, and this pin 49 fits into a grooved cam 51 formed on a cam plate 50, and the inner cam surface 51' and the outer cam surface of the grooved cam 51 are connected to each other. 51
′ is in contact with both. The cam plate 50 is connected to the motor 52
The cam plate 50 can be attached to the shaft 53 by loosening the lever nut 54 when assembling or repairing the copying machine. The angle can be adjusted by loosening the nut 54 and adjusting the rotation of the cam plate 50 with respect to the shaft 53, so that the pin 49 as a cam follower and the Kuon pin 57 are connected to the groove I cam 51 and the Kuon groove cam, respectively. If the nut 54 is tightened again with the nut 54 in contact with the desired cam surface portion of the cam plate 58, the cam plate s o Fi and therefore the grooved cam 51.
As mentioned above, the cam plate 50 also has a groove cam 58 formed therein. This grooved cam 58 has an internal cam surface 58'.
, and the outer cam surface 58', and the pin 57 is fitted in a good condition.

This bottle 57 is implanted in a pin stand 56 fixed to the tip of an arm portion 55 of the same type as the second i-ra unit 21 described above. In the illustrated embodiment, the bin 57.49 and the shaft 53 are aligned in a straight line;
It's between t-.

The grooved cam 51 is used to change the movement amount t of the lens 1640, which is driven by the motor 31C and moves along the rail 23, in response to the lens focal length error Δf during the magnification changing operation. Reference numeral 58 is for moving the mirror 14.15 along the rail 23 in order to change the total path length during the magnification changing operation, and the amount of movement is changed in accordance with the lens focal length error Δf. It is for the purpose of After adjusting the fixed phase angle of the cam plate 5o with respect to the shaft 53 as described above, if the motor 52 is rotated and the cam plate 5o is rotationally driven, if there is no error in the lens focal length, even in the same magnification image forming mode. Even in the β-magnification image forming mode, the stopper 38 (which moves by the same amount in the same direction as the pin 49 engaged with the grooved cam 51) is held at the same position in the longitudinal direction of the rail 23, but the lens focal length has the above-mentioned difference. When there is thf, the stopper 38 is held at the same position in the same magnification image forming mode as in the case where there is no error in the lens focal length in the same magnification image forming mode, while in the β magnified image forming mode The stopper 38 is located at a distance of ΔL in the longitudinal direction of the rail 23 from the position in the same-magnification image forming top mode. It is configured as described. As the cam plate 50 rotates, it engages the scoop cam 58 and the bin 5 acts as a nine-cam follower.
7 is related to the rail 230-& child direction, if there is no error in the lens focal length, the distance is displaced by /2, and if there is the error Δf in the lens focal length, the distance is /2. A distance displacement of L4/2 different by ΔL4/2 is caused.

As a result, the respective mit-14.15 positions in the same magnification image forming mode and the β magnification image forming mode establish document surface positions corresponding to the nine lens focal length errors explained in FIG. In this embodiment, 211 magnifications can be selected, so it is assumed that the cam plate 50 Fi is rotated by 180 degrees during the magnification change operation.

FIG. 4 shows the respective inner cam surfaces 51' of the grooved cams 51 and 58.
, shows the shape of 5g'. The shapes of the outer cam surfaces 51'', 58' are similar to the shapes of the inner cam surfaces 51', 58', respectively.

The area 51'a of the cam surface 51', which rotates clockwise from point O to point C3, is an arcuate area with a radius centered on the axis 53, and when forming a 1-magnification image, this area 51' The bottle 49 comes into contact with some part of a.

When forming a β-magnified image, the bin 49 comes into contact with a portion of the cam surface 51' corresponding to the error Δf in the lens focal length in an area 51'b extending clockwise from point C to point 04 on the cam surface 51'. The distance between the axis 53 and the 0□ point is larger than the radius R1 of the area 51'a, and the distance between the axis 53 and the 04 point is smaller than the radius R, which is the 03 point. The distance from the axis 53 gradually decreases as the point progresses clockwise from point 04 to point 04. And at point 01, axis 5
3 is equal to the radius B of the region 51'a.

The area 58'a on the front cam surface 58' from the 0□ point to the 0□ point rotating clockwise is an arc area at the end of the radius centered on the shaft 53, and this area 58'a is When the bottle 57 comes into contact with some part of the cam m58' when forming a magnified β image, the lens focal length Om error Δf in the area 58'b of the cam m58' from the 0 and 1 points to the 04 point rotating in the direction of the hour hand. The bottle 57 comes into contact with a portion corresponding to . This area 5
011 point in 8'b (point 011% axis 53, point C is located on a straight line, and axis 53 is point Ots, OH
) and 53 are R8◎
And the distance between point OL and axis 63 is approximately large,
The distance between the point 08 and the axis 53 is very small, and the distance from the axis 53 gradually decreases as you go clockwise from points 01 and 04. Then BIs
is determined according to the following formula. This point is 0. When the lens focal length error Δf is Δf, when the lens focal length error Δf is Δf, the bin 49 is
・If the distance between point C0 and axis 53 is t-Ru, then ∊ is determined according to the following formula. , Δf is Δf1.

Also, pay attention to the point 0 in the region 58'b of the cam surface 58'. Point C1・, axis 539 point 0・ are aligned on a straight line O Therefore, in this embodiment where the bins 49, 57 and the axis 53 are aligned on a straight line as described above, the bottle 49 comes into contact with the above point 0・ and the 9 o'clock ,
Bin 57 is at this point 0. comes into contact with. Then, if the distance between point C1 and axis 53 is , then the chicken is determined according to the following formula: R, -R, = - is Goei f.

2β The right side of the above equation is the value of 1/2 of the above-mentioned ΔL4 when Δf is 46. As is clear from the above, the area 51' of the cam surface 51'
b is for correcting the position of the lens 16 in the β magnification image forming mode in accordance with the lens focal length error, and the area 58'b of the cam surface 58' is for correcting the position of the lens 16 in the β magnification image forming mode. This is to correct the position of the mirrors 14 and 15 in accordance with the lens focal length error. Therefore, if there is no error in the lens focal length, the support pin 49 will be moved to the cam surface 51' when forming the mirror.
The bottle 57 is placed on the cam surface 58' at point C7 in the area 51'
When forming a β-magnified image, the pin 57Fi contacts the point 011 in the region 58'1, and the pin 57Fi contacts the point 015 in the CI point.
Touching the points (017 points, 01 points, axis 53.0! points.

The C11 points are aligned on a straight line.) In other words, the fixed phase angle of the cam plate 500 with respect to the axis 53 is adjusted so that the above is achieved.In addition, if the lens focal length has the error Δf, for example, , when forming a 1-magnification image, the bottle 49 comes into contact with point 08 in area 51' of the cam surface 51', and the bottle 57 comes into contact with point 011 in area 58'a of cam surface 58', and when forming a β-times image, Bin 49 is at the point C.
The bottle 57 contacts the C16 point - (01s point, Ce
Adjust the point, axis 53, O, and point so that they are aligned.

In this embodiment, 0, 1 point, 03 point, axis 53, 0 . point.

The Cu point is also 01! Point 04, axis 53, o, point 014 are also lined up on a straight line, respectively.

Now, the lens 16 and mirror 14 for forming a same-magnification image.
To explain the position adjustment of stopper 3, first
8 from the notches 3ti and 37 of the plate 35, and the lens stand 28 is made movable. Next, the nut 54 is loosened, the cam plate 50 is rotated about the shaft 53, and the bin 49.5 is moved.
The cam plate 50 is fixed to the shaft 53 by tightening the nut 54 while bringing the cam plates 7 into contact with appropriate positions within the 51'a area and 5Jll'a area of the cam surface, respectively. In this state, the position of the stopper 38 when forming a 1-size image and the position of the second mirror 21 when forming a 1-size image are respectively set.〇These positions are independent of whether there is a lens focal length error or not. They are in the same position. Next, the second lens stand 28 is moved to a position where the stopper 38 set as described above is inserted into the notch 36, and in this state, the stopper 38 is
is inserted into the notch 36 to position and fix the second lens stand 28. As a result, the position of the second lens stand 28 when forming a 1-magnification image is set. Since the position of the stopper 38 when forming a 1-magnification image is the same regardless of the presence or absence of Δf as described above, the second The position of the lens stand 28 when forming a same-magnification image is also the same regardless of the presence or absence of Δf.

Next, loosen the screw 27 and attach the lens 16 to the second lens stand 2.
8, adjust the movement in a direction parallel to the rail 23, loosen the screw 20, and move the mirror 14, 15 in a direction parallel to the rail 23 with respect to the second drill 21, The second lens 16 is placed at a position where a focused, same-size image of the original can be formed on the photoreceptor P by these two joints.
The lens stand 28 and the second mirror are fixed to the stand 21. Through this adjustment, the lens 16 and the second mirror 14, 15 are fixed to the
The fixed position on the lens stand 28 and the second mirror stand 21 is the lens l6. Corresponding to focal length error, Δf
When Δf is not O, the position of the lens 16 is ΔL on the second lens stand 28 from the lens position when Δf is O.
+ (see FIG. 1) in the longitudinal direction of the rail 23. The position of the mirror 14.15 when Δf is not O is 1t when Δf is 0.
From positions -14 and 15, on the second mirror 21, ΔL
! / 2 (see Figure 1) in the longitudinal direction of the rail 23.The above displacement direction is the direction toward the photoconductor when Δf is negative, and the direction away from the photoconductor when Δf is positive. The direction is moving away. If there is no error in the lens focal length, the lens 16 is positioned at a position corresponding to point N in FIG. 1, and the mirrors 14 and 15 set the optical position of the document surface to 01 in FIG. It is something that can be placed in a certain position.

As a result of the above-mentioned adjustment, during the same-magnification image formation process, the photoreceptor P4C forms an accurately focused image of the original at the same size.

Next, lens positioning and mirror 14.1 for β-magnification image formation
To explain the positioning in step 5, the positions of the V lenses 16 and mirrors 14° and 15 for forming the same-magnification image are as follows:
The stopper 38 is pulled out from the notch 1lj6, the second lens stand 28 is moved to a position where the notch 37 engages with the stopper 38, and the stopper 38 is inserted into the notch 37. Therefore, the lens 16 is attached to the rail 23. The reference lens 1 is moved by the distance explained in Fig. 1 in the longitudinal direction.
In this state, when the focal length of OIa is adjusted to the focal length of 6, the focal length of the lens is shifted to the position of N4 in FIG. I can't get it.

(In this state, the mirrors 14 and 15 remain at the aforementioned positions adjusted in accordance with the presence or absence of a difference in lens focal length during the same-magnification image formation.

Therefore, in this state, even if Δf is 0, a β-fold image cannot yet be obtained on the photoreceptor. ) Then, tighten the nut 54f again and insert the cam plate 50 with the stopper 38 inserted into the notch 37! , axis 53 (
This shaft 53 is rotated relative to the shaft 53 (which is held stationary at this time). As is clear from the foregoing, the simultaneous rotation of the cam plate 500 causes the grooved cams 51. Bin 49. The signal is transmitted to the stopper 38 via the rod 47, and the stopper 38 is connected to the cam plate 50.
Since it moves in a direction parallel to the longitudinal direction of the rail 23 with the zero rotation, the second lens stand 28 moves in the same direction as the movement direction of the stopper 38.

Therefore, the nine lenses 16 fixed to the stand 28 also move in the same direction. Also, the simultaneous rotational movement of the cam plate 500 is transmitted to the second Mi 21 stand 21 via the grooved cam 58 and the pin 57. Therefore, as the cam plate 50 rotates, it moves in a direction parallel to the longitudinal direction of the second mirror 21a rail 23, and therefore the mirrors 14 and 15 also move in the same direction. Therefore, the cam surface 51
With the shaft 53 fixed and in good condition, rotate the cam plate 50 to a position where the area 51'b of the force bearing surface 58' abuts the pin 49 and the area 58'b of the force surface 58' abuts the pin 57. . Further, bins 49 and 57 are respectively located in the areas 51'b and 51'b.
58'b, move the cam plate 50 to the shaft 5.
3, rotate the lens 16 and mirror 14.15
Adjust the position of the rail 23 in the direction parallel to the longitudinal direction of the rail 23. With this clause, the lens 16 and mirrors 14 and 15 are placed in a position where the photoreceptor PK original can be focused and a 9β-times image can be formed. When brought in, nuts 5-4 are tightened to secure cam plate 50 to shaft 53. LF for this
) When forming a β magnified image, the position of the stopper 38, and therefore the position of the second lens stage 28, and 3% 2 < LA 1 stage 21
The position of is set. In other words, the position of the lens 16 and the position of the mirror 14.15 during β-times image formation are determined depending on the presence or absence of lens focal length error.In other words, in this state, the bins 49.57 are set as described above. , respectively cam surface 5
1', 58' areas 51'b, 58'b,
It is in contact with a portion corresponding to the lens focal length error f.

For example, when Δf is not 0, the bins 49 and 57 are in contact with the points c and e cts in the electric areas 51'b and 58'b, respectively.Therefore, the stopper 38 is in the same position as when engraving the 1-size image. On the other hand, the distance between the notches 36 and 37 of the second lens stand 28 is set to the above distance, so the position of the second lens stand 28 is set to The lens 16 is positioned at a position moved from the position at the time of formation by the distance indicated above.
It is located at position N in the figure. Also, due to the rotation of the second mirror unit 21d and the cam $58, the pin 5
The distance from the point in the area of the 58' grave, which is the circular arc area of the radius hole, to the axis 53 in the area 58'b is R.
m (As mentioned above, the point has changed to 011 of R, - Torijurigo/Ri, so from the position when the same-magnification image was formed,
It moves by a distance of /2 and is positioned at the 9th position. Therefore, mirrors 14 and 15 adjust the optical position of the document surface to 0.
! On the other hand, when Δf is, for example, Δf1, the pin 49.57 is positioned at the point o, 0. ．． It touches each point. Therefore, the stopper 38 is located at a distance (1-β)Δf from the position when forming the same-magnification image in a direction parallel to the longitudinal direction of the rail 23, and therefore the second lens stage 2B Butterfly The position when forming a life-size image is also (l-β)Δf.

It is displaced and positioned at the 9 position. Therefore, the lens 16Fi is positioned at the point ON in FIG. 1. In addition, #r2<R1 21, the still contacting part of the pin 57 is displaced from the point in the region 58'1 to the 9th position by the distance from the axis tmi (distance from the axis tmi) in the region 358'b. The mirror 14.15 is moved.
is positioned at a position where the optical position of the document is ol.

After setting the abutment position of the pin 49.degree. 57 against the grooved cam 51.58 during the formation of a .beta. magnified image as described above, the cam plate 50 is rotated by half a rotation during the magnification changing operation. This is a multi-lens 16. The Z lenses 14 and 15 are moved from their respective equal-magnification image forming positions adjusted in accordance with the lens focal length error by respective distances adjusted in accordance with Δf, and are moved from their respective .beta. Move to the position for forming a double image or vice versa. It should be noted that the cam surface position where the pin 49.57 contacts the grooved cam 51.58 when forming a 1-magnification image and when forming a β-magnification image differs by 180 degrees with respect to the rotational direction of the cam, which can be understood from the above. When forming a β-magnified image, pin 49
．． No matter where the position of the cam surface with which the pin 57 comes into contact is adjusted, the pin 49.
1'a, 58'a will come into contact with the grooved cams 51.58.

In addition, in the above-mentioned ρυ, the shaft 5 of the cam plate 50 during β-fold image formation
In order to find the water relative fixed angular position corresponding to Δf with respect to 3, the stopper 38 is fitted into the notch 37 and the lens 16 and the stopper 38 are simultaneously moved in a good condition. First, without engaging either of the notches 36 and 37, press 7! )32゜3
3 to move the second lens stand 28, which allows a focused β-fold image of the document to be formed on the photoreceptor P.
Bring the lens 16 to a position corresponding to f, then %1
．． Then, rotate the cam plate 5o about the shaft 53 to release the stopper 3.
8 to a position where it can fit into the notch 37,
It is also possible to adopt an adjustment method in which the cam plate 5o is fixed to the shaft 53 after this adjustment work is completed. At this time mirror 14.1
5 is automatically brought to the 9 position corresponding to Δf at which a focused β-fold image of the original can be formed on the photoreceptor P by the action of the grooved cam 58.

Now, in FIG. 3, the flag 59 is fixed to the stopper support base 45, which movably supports the stopper 38, using a magnet. Therefore, as the cam plate 5o rotates, the magnet 59 moves by the same amount in the same direction as the stopper 38. On the other hand, 60 and 61 are magnetic force detection elements such as Hall ICs that sense the magnetic force of the magnet 59 and form a signal when they face each other. This magnet 5
9. The elements 60, 61 constitute a device for detecting the position of the second lens stand 28. In other words, the members 59, 60, and 61 function as a position detection device for the lens 16. The elements 60, 61 are then fixed to the plate 35, which is fixed to the base 28, in the nine positions adjacent to the recesses 36, 37, respectively.

In this case, the elements 60, 61 are fixed to the plate 35 in such a way that they face the magnet 59 when the respective notches 36, 37 are moved to a position where they can engage with the stopper 38. Therefore, the distance between the element 60 and the notch 36 and the distance between the element 61 and the notch 37 are set to be equal. Then, when the second lens stand 28 moves by the operation of the motor 34 and the magnet 59 faces the element 60 or 61, and the element 60 or 61 generates the above signal, the motor 34 and the plunger 43 The power supply to the equipment will be cut off, and their operation will cease.

That is, the shimotor 34 and the plunger are controlled by the signals from elements 60 and 61.

The operation of the above device will be explained. When the mode is changed from the fat magnification image formation mode to the β magnification image formation mode, the stopper 38 is initially engaged with the notch 36 and the bin 4
9 is in contact with the cam surface 51' in the region 51'a of the rotary cam plate 50, and the bottle 57 is in contact with the cam surface 58' of the cam plate 50 in the region '5B'h. The lens 16 and mirrors 14 and 15 are located at respective same-magnification image forming positions corresponding to the lens focal length error. Next, when the magnification mode change switch is turned on, the plunger 43 is first energized, and the stopper 38 is pulled out from the notch 36 by its operation. Next, the motor 34 rotates forward to rotate the pulley 32 in a counterclockwise direction, thereby moving the second lens stand 28 to which the lens 16 is fixed to the right in FIG. 3.

On the other hand, the motor 52 starts rotating in synchronization with the start of rotation of the J motor 34, and rotates the cam plate 50 by 180 degrees. As a result, the bottle 49Fi is brought into contact with a position corresponding to the lens focal length error Δf in the region 51'b of the force field 51'. In other words, the stopper 38 moves to a position corresponding to the above-mentioned ΔfK in the β-magnification image forming mode. Further, together with the stopper 38, the magnet 59 also moves to a position corresponding to Δf in the β magnification image forming mode. Also this cam plate 5001
Due to the 110 degree rotation, the pin 57 is located in the region 5 of the cam surface 58'.
8'b at a position corresponding to the above-mentioned Δf. In other words, the mirrors 14, 15 are moved to the β-fold image forming position corresponding to Δf.

The rotation of the cam plate 500 by 180 degrees is completed before the lens 16 reaches the position corresponding to ΔfK for forming a reduced image, that is, before the notch 37 reaches the position where it engages with the stopper 38. After this cam plate 500 has rotated 180 degrees,
! The two-lens stand 28 reaches tK to the extent that the notch 37 can be held with the stopper 38, and at this time the element 61 becomes a magnet! 9
The element 61 forms a signal, and the shimotor 34 is deenergized by this O signal, and the movement of the irises 2 lens stand 28 is stopped, and the plunger 43 is also deenergized, so that the spring 44 is deenergized.
Due to the urging force of 7, the stopper 38 rushes into the notch ↓4-. As a result, the lens 16 is positioned at a position for forming a β-fold image corresponding to ΔfK.

Conversely, when changing the mode from the β-magnification image forming mode to the same-magnification image forming mode, the stopper 38IIi is initially engaged with the notch 37, and the bottle 49 is moved inside the region 51'b of the rotary cam plate 50. Cam surface 5 at i in the part corresponding to Δf
1' and press the bottle 57. is Δ in region 58'b
It abuts against the cam surface 58' of the cam plate 50 at a portion corresponding to f. In this state, the magnification mode change switch is turned to
When N is pressed, the plunger 43 is actuated and the stopper 38 is pulled out from the notch 37 as described above, and then the motor 34 rotates in the opposite direction to drive the pulley 32 clockwise to rotate the second lens stand 28. Move it to the left in Figure 3. Then, in synchronization with the start of rotation of the motor 34, the motor 52 starts rotating and rotates the cam plate 50 again by 180 degrees, so that the bottle 49 will come into contact with the cam surface 51' in the area 51'a. As a result, the stopper 38 and the magnet 59 return to their respective positions for forming a same-magnification image. Also cam 50
By rotating 180 degrees, the cam surface 51'15 returns to the position for equal magnification use in the bottle 57 and the moth 58'a. After the cam 500 has rotated 180 degrees, the second lens stand 28 reaches a position where the notch 36 can be engaged with the stopper 38, and at this time the element 60 faces the magnet 59, so the element 60 receives a signal. motor 3 by this signal.
4 is deenergized and the movement of the second lens stand is stopped, and the plunger 43 is also deenergized and the spring 44 is activated to stop the stopper 3.
8 into the notch 36.

Note that the amount of movement of the lens when changing the multiplication is usually larger than the amount of movement of the mirror, so in the above example, the mirrors 14 and 15 are moved by the cam 58, and the lens 16 is moved by the pulleys 32 and 33. Δf of the lens 16 by moving it with the wire 30
K Corresponding movement amount correction (in other words, position correction) is performed by cam 5.
1 was used. However, mirrors 14.15 and 1-re 82. @'a, the lens 16 may be moved by a pulley-wire mechanism such as the wire 3G, and the lens 16 may be moved by a similar cam mechanism such as the O-cam i$ described above. In this case, a mechanism such as a stop position correction mechanism consisting of a movement amount correction (in other words, position correction) line corresponding to 14° 1SOAtK, the aforementioned positioning plate 35, a stopper [1 force ^s1, etc.] may be used.

In the above example, since the correction corresponding to the movement amount OAf of the lens and the lens was performed by adjusting the fixed angular position of one cam plate 500 relative to the shaft 531C, the above correction can be easily and accurately achieved.

Next, a practical 'IIIAfp4 in which the amount of movement of the lens and mirror can be corrected with a simple mechanism will be explained with reference to FIG.

In FIG. S, members and means having the same functions as those in the embodiment of FIG. 3 are given the reference numeral ``-'' between the enlarged bodies, and explanations of these will be omitted unless necessary in 411.

Now, in Figure 3 ON, the position of the stopper 380I at the time of formation was changed in accordance with the error in the lens focal length, but in the case of the tuna in Figure 5, the position of the stopper 38 was changed according to the lens focal length #jAv14 difference. # Even when forming an image at the same magnification regardless of the presence or absence
When forming a double image, the position is 41i1-, and for example, the position of the notch 37 is adjusted in accordance with Δf. In detail, 35' is a nine positioning plate fixed to the second lens stand 28, and a notch 3 into which a stopper 88' engages when forming a 1-magnification image.
6. 62 is a stopper 38 during β magnification image formation.
' is a plate piece having a notch 37 that engages with the plunger. A long i long hole 63 is provided in the plate piece 62 in a direction parallel to the longitudinal direction of the rail 23, and by fitting a screw 64 into this long hole 63 and screwing it into the plate 35', the plate piece 62 can be removed. Plate 35'
Fixed. The stopper 38' is fixed to a plunger shaft 41 connected to a plunger 43, and therefore, when the plunger 43 is activated or deenergized, the stopper 38' is retracted, extended, and moved in a direction perpendicular to the longitudinal direction of the rail 23. It does not move in a direction parallel to the longitudinal direction of the rail 23. When the stopper is putunger 48011, it is a good stopper support stand, and supports the stopper '48' so that it can move in a direction perpendicular to the longitudinal direction of the rail 2s.

Loosen the 1 screw 64 as shown above, and the plate piece 3,
The positioning lever 35' can be moved and adjusted in a direction parallel to the longitudinal direction of the rail 2s. *Notch 113 so to speak
The distance between 1 and the notch tk3 can be adjusted.

Magnet 1sFillj! Holds nine stoppers and one 4S
'KII is set to vsh0 and 9 is different from the embodiment in FIG. 3.1.
In the main guard, the position of the magnet 8110 is determined by the presence or absence of Δf. , the spacing between notch 37 and element $10 position O is set equal to the spacing between notch 36 and the OS fixed position of element soo*ss'. When they are in a state where they can enter into the notches 36 and 37, respectively, they face the magnets 59.

Well, one second electric train! A positioning plate 6s is fixed to the IK. This O positioning plate 65d, when forming the same size
It has a notch 66 into which the par 68 engages. 61
is a notch I into which the stopper 68 engages when forming a β-magnified image.
It is a plate piece having 69. The rail 23 is attached to this O plate piece 69.
A long hole γ0 is provided in a direction parallel to the longitudinal direction of the plate 69. By fitting a screw 71 into the long hole 70 and screwing it into the plate piece 65, the plate piece 69 is fixed to the plate 65. By loosening the 91 lever screws 11, the plate piece 65 can be adjusted to move relative to the positioning plate 65 in a direction parallel to the longitudinal direction of the rail 290. In other words, the spacing between the notches 1167 and 660 can be adjusted.

The stopper 68 is supported movably in a direction perpendicular to the longitudinal direction of the rule 280 by a stopper support 72 fixed at a fixed position, and does not move in a direction parallel to the longitudinal direction of the rail 3so. This O stopper 18 is fixed to the expansion electromagnetic plunger γ30y and the Tunger shaft 74. Le, l
! 9 plunger 7sO is activated, deenergized by Shireru 23
move forward and backward in a direction perpendicular to the longitudinal direction of the And the stopper 68 engages when the plunger 7s is deenergized.
It is urged to plunge into the above-mentioned notch by the elastic force of.

Numeral 76 is a nine magnet fixed to one stopper 72 which is held at a fixed position. 77.7JI is Ho#IcOmai
These are air detection elements], and each generates a signal when it moves to a position facing the magnet 76. When the ζO compensation sign is formed at liL, the action of plunge v-780 is deactivated, and the action of 7-j188, which will be described later, is also deactivated. Plunger 73, motor 83
However, as will be explained later, the magnet 76 and the element tear.

7S is the second sink 31, and therefore also the cellar 14, l.
5c) Configuring the position detection device. The distance between the notch 66 and the O1i position of the element 71 on the plate 65 is set equal to the distance between the notch 67 and the position where the element tSOw is fixed to the piece 69. And the elements 77, 78 are the stoppers 66
The tortoises are in a state where they can enter into the notches @6 and 67, respectively, and are opposed to the magnets 76, respectively.

A wire 79 is connected to the second liner 21 via a wire loosening spring 80. Spring 80 is normally connected to base 21 and wire 79 in a stretched state. The wire 19 is connected to the pulleys 81 and 8, and the pulley 83 is connected to the reversible output shaft. When the WJ is set, the mode is changed to the 679x image forming mode, etc., the motor 183 rotates forward, the pulley 81 is rotated clockwise, and the mirror 14,150m is rotated.
! The set second electric power unit 21 moves to the left in the figure along the rail 23. Conversely, when changing from the β-magnification image formation mode to the same-magnification image formation mode, the morph 81 is reversed and the pulley 81 is rotated counterclockwise.
Each machine 21 moves to the right in the figure.

Now, in the apparatus shown in FIG. 5, the positions of the lens 16 and mirrors 14, 15 for the stopped image forming mode are adjusted as follows.

First, the stopper 38', 6g, the second lens stand 28,
Positioning plates 35' each fixed to the second i-ra unit 21
, 65, respectively, to hold the second lens stand 28 and the second mirror stand 21 stationary at the positions for forming a same-magnification image.

Next, screw 27. ! Loosen 0 and remove lens 16, mirror 14.
15, respectively held stationary for nine machines 28 and 21,
The lens 16 and the mirrors 14 and 15 are moved and adjusted in a direction parallel to the longitudinal direction of the rail 23 to bring the original into focus on the photoreceptor P and a 9 equal magnification image is formed, and the respective positions are determined. Tighten screws 27 and 20 in 9 steps and tighten lens 16.
, and the filters 14, 15 are fixed to the stands 28, 21, respectively.

As is clear from the above, the lens 16 obtained by the above adjustment, the base 2g of Mi9-14.15, and the ff1
Each position line on l corresponds to a lens focal length error.

Next, loosen the screws 64 and 71 and attach the plate pieces 62 and 69 to the plate 35'.
, 65. On the other hand, stopper 3
8', 68 are respectively cutouts 36, 37, and 66.
67, and the stand 28.21 is made movable along the rail 23. Then, the tables 28 and 21 are moved, and the lens 16 and mirrors 14 and 1B are also moved to a position where a focused 9β magnified image of the original can be formed on the photoreceptor P. The positions of the lens 16, mirrors 14, 150 at this time correspond to ΔfK as described above. Then, while maintaining the respective positions of the bases 28 and 21 as before, the plate pieces 62 and 6 are
9 are moved and adjusted in the above direction relative to the plates 35' and 65 respectively, and the notches 37 and 67 are brought into positions where they can engage with the stoppers 38' and 6g, respectively. 38'.

68, tighten the screws 64 and 71 to connect the plate pieces 62 and 6G to the plates 35' and 6!, respectively. Kfl is determined.

The notch 36°370 interval obtained by this adjustment is equal to the aforementioned Lslc, and the interval between the notches 66 and 67 is equal to the aforementioned distance 10. In other words, the amount of movement of the lens 16 during the magnification changing operation The amount of movement of the mirrors 14 and 15 is corrected in accordance with ΔfK by adjusting the intervals between the notches 36 and 37 and the intervals between the notches 66 and 7.
The operation mode of the apparatus shown in FIG. 5 when changing the magnification is as follows. When changing from the same magnification image forming mode to the β magnified image forming mode, the stoppers 38' and 68 are initially engaged with the notches 36.66, respectively, but when the magnification change switch is turned on, the plunger 43 .73 is activated and the stopper 38'.

68 is the above-mentioned notch: I6, retreat from 66, then K-1
34 and 83 rotate normally to move the table 28 to the right in the figure and the table 21 to the left in the figure. When the platform 28.21 moves to a position where the elements 61.78 face the magnets 59 and 7, respectively, the elements 61.78 form the signals and the motor 134
．． 83 is deenergized and the movement of the platforms 28 and 210 is stopped, and the plungers 43 and 73 are also deenergized and the stopper 38' is stopped.

68 project into the notches 37 and 67, respectively.

As a result, the levers 28 and 21 are positioned at the position when forming the β-fold image, and the lenses 141 and 14.Is are held at positions corresponding to ^fK when forming the β-fold image. On the other hand, when changing from the β magnification image forming mode to the same magnification image forming mode, the stoppers 38' and 68 are initially engaged with the notches 37° and 67, respectively, but when the magnification change switch is turned on, The plungers 43, 73 operate and the stoppers 38', 68 retreat from the notches 37, 67, and then the motors 34, 83 reverse, moving the platform 28 to the left in the figure and the platform 21 to the right in the figure. element 60.
．． 77 to the position where they face the magnets 59 and 76, respectively.
．． 21 is moved, the element 60.77 forms the signal, the motor 34.83 is de-energized, the movement of the platform 28, 210 is stopped, and the plunger 4B, 73 is also de-energized, causing the stopper 38', 68 to be de-energized. are respectively said notches 36°6
6 to engage. As a result, the stands 2 @ and 21 are positioned at the same position when forming the same-size lens, and the lens iG and the lens 14
．． The circle is held at the position corresponding to Δf when forming a 15-hiro image at the same magnification.

In addition, as you can see from the above-mentioned Shieto, the stand is 21°28Fi,
When forming a same-magnification image, each lens is held at the same position regardless of whether there is a focal length error or not. (However, the lens 16 and mirrors 14 and 15 each have a
) (correspondingly located at the 9th position) are located at positions corresponding to Δf during β-fold image formation.

In the above embodiments, when forming an original image on a photoreceptor, the original is placed on the photoreceptor and the nine-fold draft plate is moved. However, the original is moved using rollers, belts, etc. The present invention can also be applied to an apparatus that forms an image on a photoreceptor. 9. The present invention is a copying apparatus of the document table identification type, which is configured to scan M@ by moving a mirror or the like with respect to an original held stationary at a fixed position on a document table fixed at a fixed position. 4 can be applied to Next, in Figure 6, such fruit 1
/jA example will be explained. In addition, in the above embodiment, in order to obtain a same-magnification image that matches the original O focus, the total optical path length and the ratio of the object world side optical path length and the image field side optical path length are changed during the magnification changing operation. The mirror 14.
The position of lens 15 and the position of lens 16 were corrected in accordance with ΔfK, but in the next implementation, the optical path length was corrected to form the document O in focus by changing the optical path length during the magnification change operation. Because the mirror is not configured to move, you have to adjust the position & do so.

Now, in Fig. 6, there are members that perform the same function as the above-mentioned j and hook,
Means are marked with the same 〇 symbol, and only necessary explanations are omitted. In the figure, reference numeral 79 is fixed at a fixed position, and an original 0 to be copied is held stationary on an original loading table 9. 82 is the first scanning electric error, which is similar to Kai 2-13 and has a 45
It is set at a degree angle. Reference numerals 83 and 84 denote mirrors constituting the second scanning mirror structure, which are provided perpendicularly to the mirrors 14 and 15 and parallel to the mirrors 82 and 82. 81 is a 17A draft illumination lamp. The mirror 82 and the lamp $1 are fixed to the first movable slider 8s, and the mirrors 83 and 84 are fixed to the second movable slider 86. and stand 85
．． Slide bearings 87 and 88 are fixed to each of the slide bearings 86, and these bearings 87 and 88 are fitted to a guide rail 89 that is long in the direction parallel to the document table 79 so as to be slidable in the longitudinal direction thereof.

A pulley 91 is rotatably supported on the second movable roller 86 by a shaft 90 of the same type.

Therefore, the pulley 91 is a movable pulley that moves in parallel with the document table under the guide of the rail 890 together with the table 86. Jin's pulley 9
1 is hung with a wire 92. One end of the wire 92 is fixed to a rotating drive pulley 93 in a fixed position,
The other end is a long guide rail parallel to the document surface (not shown) similar to the guide rail 23 shown in Figures 3 and 5.
Therefore, it is fixed to a wire fixing plate 94 which is movably supported by the document platen and is movable in a direction parallel to the document table. The cover plate 94 moves during the magnification changing operation, but remains stationary during the copying operation to form the original *# on the photoreceptor P. Goo again 179
1 and 93, the wire 92 is fixed to the first movable 2-ra unit 85 by a wire holding plate 95. Wire holding plate 9
5 is fixed to the stand 85 by a screw 96 screwed into the stand 85, and the wire 92 is pressed and fixed to the stand 85 by this. Therefore, by loosening the screw 96, the position at which the stand 850 is fixed to the wire 92 can be adjusted.

Numeral 97 is a tension spring, one end of which is fixed to the second movable mirror 86, and the other end fixed to a stationary member 98 within the main body of the copying machine. When this spring stand 86 travels to the right in the figure, it is stretched and stores elastic force. Also, 99 is Kari-Yu dera]
, the pulley 93 is connected to its output shaft. When a copying operation is started at the selected magnification, the O-morph 99 is activated to rotate the pulley 93 clockwise. As a result, the platforms 85 and 86 move forward in the direction of the arrow wc parallel to the document table at a speed of 1:1/2 O in accordance with the movable pulley base 11 while stretching the spring 97. Therefore, mirror 82 and mirrors 88 and 84 move forward in the direction of the arrow at a speed ratio of 1:1/20 to scan the original.

Mitsu-81 and mirrors 83 and 84 are parallel to the document table 79
As is well known, it moves at a speed ratio of 1:1/2.
The optical path length between the original and the lens is determined by J! [This is to maintain the round length in the document scanning diagram, which is set according to the selected magnification.

In addition, the relationship between the forward movement speed v1 of the mirror 82 and the circumferential speed η of the photoreceptor pom, ■/V;
It is determined according to wr, H 2. Such speed ratio setting means are well known.

When the document scanning is completed, the motor 99Fi is deenergized, and the elastic force of the spring 970 moves the stands 85, 116 in the direction O opposite to the arrow 1:1/! They move backward at a speed ratio of , and return to the respective Oa excitation point positions. When the document scan is completed, the mirror 82
and (La 1 83. 84 is opposite to the arrow O direction K 1 2 1/
It moves backward at a speed ratio of 2 and returns to its respective forward movement starting position.

As will be described later, the forward movement starting point position of the second movable motor ($6) is changed in accordance with the selected magnification by the operation of the Kōbai wheel changer. In the same-magnification image forming mode of the thumb mirror 83, 84, the forward movement starting point position is the solid line position in the figure, and in the β magnification image forming mode, the forward fIIk starting point position is the broken line position 8 g', 8 in the figure O.
It is 4'. However, mirror 83°84 and therefore also stand 8
6, forward movement starting point position 83' in β magnification image forming mode,
114' is corrected corresponding to the lens focal length error. However, in the non-embodiment, the printer 82, and therefore the front plate 5
The SOS forward movement starting point position is the same when forming a 1-magnification image and when forming a β-magnification image. However, the mirror price is $2, so the stand 85
When assembling or repairing the device, the lens focal length m can be adjusted by loosening the screw 96, moving the base 85, and adjusting the fixed position of the base 85 relative to the wire 92. It is corrected in accordance with the error ΔfK.

Now, the O light from the 9 originals scanned by Mi 2-82 and i-2 83.84 moves the mirror 82.83°84 to l[
K is reflected and passes through the 9th lens 16, then Mi)-1
00, 101, and 101 are reflected by the shoe and enter the drum PK, forming the originals l1IO'yt and so. mirror 100at
Parallel to Ra 84, Toshi, 42-h Bahami? -100
The reed 102 is in a right-angled relationship with the pusher 101, and the reed 102 is parallel to the pusher 101.N? The optical path is parallel to the original table between -'84 and 100.

The above-mentioned mirrors 100, 101, and 102 are fixed mirrors that do not move when forming an original image on the photoreceptor or when changing the magnification. However, the position of pin':)-100°101 is adjusted in accordance with Δf during device assembly, repair, etc. That is, mirror 101. Zo.

One Mira is fixed at 103K. One Mira 103
has a long hole 104 extending in a direction parallel to the document table, and a K screw 105 is fitted into the long hole 104, and by screwing this screw 105 to a stationary member 106 of the copying machine main body, The Mitsu unit 103 is also the mirror 100,
101 is fixed to this stationary member 106. By loosening the screw 105 and adjusting the movement of the table 103 parallel to the document table, the positions of the scissors 100 and 101 can be adjusted in the same direction.

Now, the wire fixing plate 94 is located at the solid line position in the figure when forming a normal magnification image, and is located at the broken line position when forming a β magnification image. When the plate 94 moves to the left due to the magnification changing operation of the tab, the second movable mirror 86 to which the mirrors 83 and 84 are fixed moves to the left by the elastic force of the spring 970, and when the plate 94 moves to the right, the wire 92, the pulley 91 moves the 5-ra unit 86 to the right. In short, based on the principle of a movable pulley, the forward movement starting point position of the mirrors 83 and 84 moves a distance of 1/2 of the amount of movement of the plate 94.

(Note that the total path length between the original and the photoreceptor changes by twice the amount of movement of the forward movement starting point position of the sliders 83 and 84.) At this time, the pulley 93 does not rotate, so the tool 82 The fixed first movable lens 85 moves, and the position of the wire fixed plate 940 on the same magnification image forming drive remains constant regardless of the presence or absence of a lens focal length error. The position 94' at the time of double image formation is corrected in accordance with the lens focal length error. In other words, the amount of movement of Enoki 94 when changing the magnification is corrected in accordance with the lens focal length error, so that when the forward movement starting point position of pulley 91, and thus mirrors 83 and 84, is at the lens focus, the original , the total optical path length between the photoreceptors is changed.

Therefore, the amount of movement of the wire fixing plate 94 is (1-β)2f/β when the error in the lens focal length is 1:1,
(1+β)f
/β and t, it is possible to form a β-fold image on the photoreceptor with the original in focus, but if there is an error Δf in the lens focal length, then (1-Ji)''(f+Δf)/β, The above total optical path length is (1-β)8(f+Δf)/
By increasing the length by β, it is possible to form a magnification of 9β which allows the original to be focused on the photoconductor by K.

The wire fixing plate 94 is shown in FIGS. 3 and 4 or 5.
It is moved by a mechanism similar to that explained in the figures. One second electric power line in Figures 3 and 4 or Figure 5 2
1 may be replaced with the wire fixing plate 114.

However, when applying the cam 5s to the example in this figure, the area S 8' b OC of the cam surface 58' explained in Figures 3 and 4
The distance R1 between the ow point and the axis 53 is determined according to the following formula.

Bird - Bird x = L.

Further, when the cam 58 is applied to the example shown in the figure, the distance between the cam surface area ss'1socts and the shaft 5s is determined according to the following 2.

R3-circle=-〇2 gloss and ~f.

β Also, the lens 16 in this example is supported and moved by a mechanism similar to that explained in FIGS. 3 and 4, and FIG.
stomach. However, in the case of the example in this figure, the screw hole 26 may normally be an O-round hole, and there is no need to adjust the fixing position to the lens 160 unit 28 according to Δf as described above. In this case, when there is no error in the lens focal length, the lens 16 moves by the above-mentioned distance by the magnification changing operation, and when there is an error Δf in the lens focal length, the lens 16 moves by the above-mentioned distance (Ll-ΔI4).
), and in order to make it possible to form a 9β-times image where the original is in focus on the photoreceptor, the lens position that can be discussed in #*11 formation image is corrected in accordance with the f. It is now possible to do so.

Note that the hook method corresponding to the position of the lens 16 in the β-magnification image forming mode and ΔI of the forward movement starting point position of the mirrors 83 and 84 is as described in Section 3. 4 and 5 are the same as in 9.

The lens 16 in the β magnification image forming mode is implemented in a large size.

That is, when the lens 16 is placed in the position for forming the same magnification soda and the mechanism shown in FIG. (In this example, the bottle 57 is attached to the wire fixing plate 94,
With the relative positional relationship fixed with arms etc.,
When using the mechanism shown in FIG. In the example, the notches 66 are provided in a positioning plate fixed to the wire fixing plate 94), respectively. Then, as described above, the lens stand and the wire fixing plate 94 are positioned in the same-magnification image forming mode, and after death, the lens 1aO position and the forward movement starting point position of the mirrors 83, 84, etc. are adjusted to the same fuse position. After adapting to the forming mode, the positions of 2-82 and 100 and 101 are adjusted in accordance with the lens focal length error. That is, screw 96
Loosen the first movable lever 8 to which the mirror 82 is fixed.
s is moved back and forth relative to the fixed second movable unit 86 of the mirrors 83, 84. As a result, the optical path length between the document and the lens, that is, the optical path length on the object space side of the lens changes. ), tighten the screw 9IA again and connect the first movable unit 21 AS to the wire 92.
to be identified. On the other hand, loosen screw 105? 9-io
o.

11014D is fixed and 10m per 9gira lens 16 and $
2-102. As a result, the optical path length between the lens and the photoreceptor, that is, the optical path length on the image space side of the lens changes, but when this optical path length becomes 2 (f + Δf), tighten the screw 105 again and set the mirror to 1O3. is fixed to an immovable member. By adjusting the above, the total path length between the document and the photoreceptor, the document.

The ratio of the optical path length between the lens and the optical path length between the lens and the photoreceptor is set to a value that allows a focused 9 equal magnification image of the document to be formed on the photoreceptor.

The above-mentioned all-Party leader in the equal-scale formation mode as shown above,
After the above-mentioned correction corresponding to the optical path length ratio Δf, the amount of movement of the lens 16 and the amount of movement of the mirror 83° 840 at the time of changing to the β magnification image forming mode are corrected corresponding to xf as described above. For example, even in the β-times image forming mode, a β-times MII image can be formed on the photoreceptor in focus.

In addition, in the case of m5ll, the screw hole 104 is normally set as an O round hole, and the mirrors 190 and 101 are placed in a fixed position E with respect to the immovable member io6.
It is also possible to set lf and not perform position correction for fK. In this case, as in Figures 3 and 5, the relative fixing position of the lens 160 to the lens stand 28 is set by the elongated hole 2.
6 and screw 27, and by adjusting the relative fixed position of the lens 16 with respect to the stand 28, the optical path length Δfl between the lens and the photoreceptor in the same-magnification image forming mode (corresponding correction is made, - inferior) The correction corresponding to ΔfK of the total path length and the optical path length between the document and the lens in the double image forming mode is performed by adjusting the relative fixed position of the first movable frame 85, and therefore also of the f-shield 82, with respect to the wire 92. In other words, the adjustment is performed by adjusting the relative positional relationship with respect to the first
One movable construction machine 8s, therefore t9 mirror 82 wire 9
Corresponding to Δf of the relative identification position with respect to 2, K can also be set so that the round adjustment is not performed. In this case as well, the relative fixing position with respect to the lens 160 unit 28 is determined by the elongated hole 26 and the screw 21 in the same way as above.
Make it hot by adjusting the ζO lens 16C) Base 2
1-magnification image formation mode K by adjusting the relative fixed position O to 8
jl) ms, nine corrections are made corresponding to Δf of the optical path length between the lenses, and one mirror is used to correct the total path length in the inferior magnification image formation mode and the optical path length between the lens, I & light body. 103
0. 9 and mirror 100.101 O.

This is done at a fixed position am with respect to the missing member 10G.

In any case, both of the above two cases involve conversion from the same-magnification image formation mode to the β-magnification image formation mode.

In the implementation explained in the 6th WA, first, in the β-fold image formation mode, the ratio of the O total optical path length and the O optical path length before and after the lens is set to Δ
After correcting in accordance with f, the amount of movement of the lens 16, the amount of movement of the mirror ms, and the amount of movement of the g4tv* movement starting point position when changing to the same-magnification image forming mode may be corrected in accordance with Δf.

In the above example, a copying machine that can select from the same magnification image forming mode and the IxII format mode and the 02' type mode is exemplified. However, it can also be applied to an apparatus in which the enlargement II formation mode can be selected.

Further, although the above embodiments have exemplified the device configured to move the lens along the optical axis, the present invention has the following features: It can also be applied to an apparatus in which the lens is moved in a direction oblique to the optical axis by a magnification changing operation in order to form the lens close together. In this case, each of the above formulas is made to correspond to the amount of lens movement in the optical axis direction.

Furthermore, the present invention uses a C0D (charge-coupled device) or the like as a photoreceptor, and once changes the information of an optical image into an electric signal,
Furthermore, it can also be applied to an image processing device that uses the electrical signals to form a desired visible image.

In any case, according to the present invention, it is possible to correct variations that inevitably occur in the focal length of actual lenses, and to
This mode corresponds accurately to the 9-magnification mode which is also selected in the 9-magnification mode, and can form a 9-magnification original image on the photoreceptor with in-focus foreshadowing.

[Brief explanation of the drawing]

Fig. 111 is an optical path development diagram for explaining the first application of the present invention, Fig. #I2 is an explanatory diagram of an electrophotographic copying machine to which the present invention can be applied, and Fig. 3 is an explanatory diagram of an electrophotographic copying machine to which the present invention can be applied. Main parts are explained, Figure 4 is an explanatory diagram of the nine cams used in the embodiment in Figure 3, and Figure 5 is an explanatory diagram of the nine cams used in the embodiment of the present invention. FIG. 6 is an explanatory diagram of still another embodiment of the present invention. O is the original, P is the photoconductor, 13, 14.15 is the Otsu-
116 is a lens, i8 is one first lens, 19 daughter long hole, 2
0 is a screw, 21 is a second building rail, 23 is a guide rail,
25 is a Jlil lens stand, 26 is a long hole, 27 is a screw, 2
8 is the second lens stand, 36.11a7 is the notch, 88.3
8' is a stopper, 4s is a movable stopper support, 45
' is a fixed stopper support, 49 is a cam follower, 50 is a cam plate, 51 is a grooved cam, 53 is a cam drive shaft, 1
4ti nut, 57 is cam 7 orabishi, 58 is groove cam, 62 is plate piece, 63 is long hole, 64 is screw, 6147 is notch, 68 is pin, 69 is plate piece, 70 is long hole, 71 is screw , 82, 83° 84 is a mirror, 85 is one first movable mirror, 86 is one second movable mirror, 91 is a pulley, 92 is a wire, 94 is a wire fixing plate, 95 is a wire holding plate, 9
6 is a screw, Zoo, 101 is a screw, 103 is a mirror, 104 is a long hole, and 105 is a screw.

Claims (1)

[Claims] In a variable magnification optical device that has a mirror and a lens and projects an original image onto a photosensitive surface at a selected magnification, when changing the image magnification, the lens position and mirror position corresponding to the selected magnification are changed to the lens focal length. A variable magnification optical device 0 characterized by comprising a lens position correcting means and a mirror position correcting means, each correcting according to the amount of error.