JPH0328694B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to reduction and enlargement of copying machines.
The present invention relates to a copying magnification conversion device that converts magnification.

Conventional configurations and their problems Conventionally, the copying magnification conversion device used in copying machines such as a movable document table type or a fixed document table type consists of a constant-velocity reflector that moves at a speed ratio of 2:1 and a semi-uniform mirror that moves at a speed ratio of 2:1. This can be done by changing the positional relationship with the fast reflector and moving the lens position back and forth accordingly, or by placing multiple lenses in the device body in advance and replacing them. is taken.

The reason for doing this is to satisfy 1/a+1/b=1/f (where a is the distance between the lens and the subject, b is the distance between the lens and the image, and f is the focal length of the lens). In order to maintain the optical positional relationship between the distance a between the lens and the subject and the distance b between the lens and the image, and to make the ratio of a and b the desired magnification of reduction and enlargement. The movement of the reflecting mirror and the lens are usually moved by separate means such as cams. Therefore,
The mechanisms and configurations thereof have become extremely complex, and drive motors and the like are also required to drive each component, which has been a factor in increasing costs. In addition, when using a cam mechanism to set the position of the reflector or lens according to the copying magnification, if the magnification is set too close to each other, it will be difficult to design the cam, making selection impossible. It could not be said that there was a high degree of freedom in setting the rate. Furthermore, the variable magnification mechanisms used in conventional copying machines are all large in size, which hinders the miniaturization of copying machines.

Furthermore, in order to perform multiple stages of reduction and enlargement, it is now possible to change and adjust the positions of several locations according to each magnification.
It had many drawbacks, such as not being able to easily focus at any magnification with a single operation, making it inconvenient to use.

OBJECT OF THE INVENTION The present invention aims to eliminate the drawbacks of the above-mentioned conventional examples, and it is an object of the present invention to change the magnification from reduction to enlargement using a fixed copying machine, and to set the magnification. An object of the present invention is to provide a copying magnification converting device that has a very large degree of freedom in image processing, and can also easily adjust the focus even when using lenses that vary in focal length. It is.

Structure of the Invention In order to achieve the above object, the present invention provides a first slider that slides on a first straight line, and a second slider that slides on a second straight line that intersects the first straight line at a constant angle θ. The vertical distance between the moving second slider and a point on the first straight line to the second straight line is A, and A
A fulcrum is provided at a position extended by a distance of a first reflecting mirror disposed across a lens having a focal length f that changes the magnification of the distance and the distance moved in a direction parallel to the first straight line as the amount of movement of the second slider; is the moving distance of the third reflecting mirror, and the relationship between A, θ, and f is f=2A/tanθ, and the first straight line and The angle θ at which the second straight lines intersect can be adjusted.

DESCRIPTION OF EMBODIMENTS Examples of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a projection diagram for explaining obtaining a reduced image, and as shown in the figure, the focal length f
When using the lens 1, if the subject 2 is 2f away from the center O of the lens, the image 3 of the subject 2 will be formed at the same magnification on the opposite side of the lens, 2f away. Subject 2 is at the center of lens 1
If the distance x is further away from the position 2f away from the center O of the lens 1, the image 3 will be formed at a reduced position 2y closer to the lens than the position 2f away from the center O of the lens 1. The height of subject 2 is now h
If the height of the reduced image obtained when this object is further separated by a distance x is mh, then from Figure 1 mh/h=2f−2y/2f+x ……(1) h/f=mh/f −2y (2) (where m is the ratio between the subject and the image) is obtained. Furthermore, by eliminating m and h from the above equations (1) and (2), the following equation is obtained: y=fx/2f+2x ().

Next, the principle of reduction and enlargement according to the present invention will be explained using FIG. 2. FIG. 2 is a diagram thereof, and the extended ends of straight line 4 and straight line 5 intersect at an angle θ. A straight line 7 is made to hang down from a point 6 on the first straight line 4, and the point of intersection with the second straight line 5 is set to 8. Let A be the distance between points 6 and 8,
Furthermore, a fulcrum 9 is set at a distance equal to the distance A on the extension of the straight line 7 from the point 8. And the first
Point 10 is located a distance x away from point 6 on straight line 4.
and the second straight line 5 of the straight line 11 connecting with the fulcrum 9
If the intersection point is 12, and the distance between this point 12 and the vertical line 7 parallel to the first straight line 4 is y, the following equation is obtained.

x/2A=y/A-y tanθ...(3) Transform equation (3) to obtain y=Ax/2A+x tanθ...(). Comparing this obtained equation () with the previously obtained equation (), f=2A/tanθ...(), it can be seen that the two previously obtained equations match.

Note that when the point 10 on the first straight line 4 is located to the right of the point 6 in the figure, the mode is reduced, and when the point 10 is located to the left of the point 6, it is the enlarged mode. be. As mentioned earlier, the position of point 6 is the same magnification mode.

Next, the arrangement relationship between the reflecting mirror and the lens according to the present invention will be explained. FIG. 3 is a diagram showing its arrangement and configuration, and shows six mirrors and lenses from the first mirror 13 to the sixth mirror 18. The first reflecting mirror 13 is inclined at an angle of 45 degrees with respect to the surface of the subject 2 such as a document, the second mirror 14 is parallel to the first mirror 13, and the third mirror 15 is inclined at an angle of 90 degrees. It is provided integrally and is configured as a second reflecting mirror. And this first
The second reflecting mirror and the second reflecting mirror are adapted to move at a speed ratio of 2:1. The optical axis of the lens 1 is parallel to the surface of the subject 2 (in this embodiment, the surface of the original to be copied). The fourth mirror 16 is connected to the third mirror 1 so as to bend the optical axis passing through this lens 1 at right angles.
5 and is inclined at 45 degrees, and a fifth mirror 17 is integrally provided at an angle of 90 degrees and is configured as a third reflecting mirror. Therefore,
The light from lens 1 will be turned back in the opposite direction. The light projected and reflected in this way is further bent by the sixth mirror 18 and sent to the photoreceptor drum 1.
It is projected onto the surface of 9. In this example, lens 1
is fixed to the main body of the copying machine.

Here, when trying to reduce the image of the subject 2, the first reflecting mirror 13 is moved a distance x to the position 13' in the direction of the lens 1 in FIG. The reflecting mirrors 16 and 17 are brought closer to the lens 1 by a distance of y to positions 16' and 17'. If the amount of movement of x and y at this time is moved according to the relationship expressed by the above-mentioned equation (), a state in focus can always be obtained.

The light passing through lens 1 is bent by the third reflecting mirror and returns to its original direction, so if the third reflecting mirror moves a distance of y, the image itself will approach the lens by 2y. , it is understood that the relationship is consistent with that shown in FIG.

For this reason, the present invention has the relationship of the above-mentioned formula (), and has a variable magnification ratio by interlocking the movement of the first reflecting mirror and the third reflecting mirror by a mechanism that operates according to the formula (). It provides a calculation mechanism that allows the camera to always focus on the subject.

Hereinafter, a specific embodiment of the present invention will be described in which a copying magnification conversion apparatus is configured based on the above-described principle.

Figures 4 and 5 are configuration diagrams of the optical system, in which the first reflecting mirror and the second reflecting mirror are moved at a speed ratio of 2:1, and when changing magnification, the first reflecting mirror and the second reflecting mirror are always in focus. A configuration in which the first reflecting mirror and the third reflecting mirror are linked is shown.

In FIG. 4, the first mirror 13 is attached to and held by a constant velocity support member 20, and is slidably held and guided by a first guide shaft 21. The second mirror 14 and the third mirror 15 are attached to a half-speed support member 22, and are slidably held and guided by a second guide shaft 23. Further, the fourth mirror 16 and the fifth mirror 17 are also attached to the third support member 24, and the second mirror 17 mentioned above is also attached to the third support member 24.
It is adapted to be slidably held and guided by a guide shaft 23 of. The constant velocity support member 20 and the half velocity support member 22 are configured to be driven by a wire system driven by an optical system at a speed ratio of 2:1.

A wire 26 wound several times around a drive pulley 25 of the optical system fixed to the main body is connected to the half-speed support member 2 via fixed pulleys 27 and 28 fixed to the main body.
It is wound 180 degrees around a movable pulley 29 provided at 2, changes direction by a fixed pulley 30, and is sent to a terminal 31 provided on a slider of a variable magnification device, which will be described later. Here, the terminal 31 is fixed and held at a constant position during normal copying operation, that is, when the constant speed support member 20 and the half speed support member 22 move at a speed ratio of 2:1. When doubling, move as described below.

The wire 26 coming out of the terminal 31 is connected to the fixed pulley 32
A movable pulley 33 is folded back at
It is turned back again and returns to the drive pulley 25 from the fixed pulley 34 via the fixed pulley 27.

One end 35 of the constant velocity support member 20 is connected to a fixed pulley 28
and a movable pulley 29. Therefore, when the drive pulley 25 rotates in the clockwise direction indicated by arrow G, the constant velocity support member 20 moves to the left, and at the same time, the half speed support member 22 also moves at half the speed. When the optical exposure scan is completed, the drive pulley 25
rotates in the opposite direction, and each support member returns to its position before the start of scanning.

Note that 36 is a locking member such as a pin that coaxially supports the movable pulleys 29 and 33 and is provided on the half-speed support member 22. Further, this pin is not limited to this embodiment, and may be provided at another location on the half-speed support member 22.

Reference numeral 37 denotes a lever, which has an engaging portion 38 such as a notch formed at a position corresponding to the aforementioned pin 36, and is configured to swing up and down by a solenoid 39 connected to one end.

Next, a variable magnification mechanism for interlockingly displacing each support member during variable magnification will be described with reference to FIG.

FIG. 5 is a plan configuration diagram in which the relationship between x and y shown in FIG.
A first guide member 41 with a diameter of 0.40' is provided parallel to the optical axis of the lens 1. A first slider 42 is supported by the first guide member 41 so that it can slide smoothly while being guided by a guide shaft. The first guide member 41 is provided with two guide shafts 43 and 43' that form a second straight line that intersects the first straight line at a constant angle θ so as to satisfy the relationship of formula (). Two guide members 44 are provided, and a second slider 45 is similarly supported on the second guide member 44 so that it can be guided by a guide shaft and slid smoothly. The first slider 42 and the second slider 45 are provided with pins 46 and 47, respectively, and are formed into a lever 48 that uses the fulcrum 9 as a rotatable support and swings around this. It is configured to fit into and interlock with the elongated hole 48'. In addition, the first guide member 4
1, a third slider 49 is guided by a guide shaft and supported to slide smoothly, and a pin 47 provided in the second slider 45 is inserted into a long hole 49' formed at the other end. It is configured so that the levers 48 and 48 are fitted together and interlocked with the swinging movement of the lever 48. Furthermore, a pin 50 is implanted in the first slider 42, and a plurality of holes 53 for setting magnification are formed in a positioning plate 52 which is moved up and down vertically on the plane of the paper by a solenoid 51. They are designed to fit together. The third slider 49 described above is provided with a terminal 54 as shown in the figure, and this terminal 54 is connected to the wire 5 for variable magnification.
5 is attached. The wire 55 is folded back via a fixed roller 56 and wound around a pulley 57. The pulley 57 is always urged to rotate in the counterclockwise direction indicated by arrow M by a spring or the like.
A portion 58 of the third support member 24 is fixed to the wire 55 between the fixed pulley 56 and the pulley 57.

In such a configuration, when the terminal 31 provided on the first slider 42 is driven by the wire 26, the first slider 42 also slides in the left-right direction accordingly. At this time, since the lever 48 also swings around the rotation support part 9, the second slider 4
5 and the third slider 49 will also slide in conjunction with each other.

As a result, when the terminal 31 of the first slider 42 moves a distance x to the right as shown in FIG. 2 from the same position, that is, the position where the lever 48 is vertical in FIG. The second slider 45 similarly moves on the second guide member 44 from point 8 to point 12.
At this time, the second slider 45 is attached to the first guide member 4.
The third slider 49 guided by 1 is moved. Therefore, for the amount of movement of the second slider 45 from point 8 to point 12, the third slider 49 moves by the distance y in the parallel direction to the first guide member 41, and The terminal 54 of the slider 49 is
It will move to the right by the distance y calculated by the formula. In other words, if the amount of movement of the terminal 31 is the amount of movement of the first mirror 13 shown in FIG. It is possible to change the reduction and enlargement ratio depending on the state.

Further, the second guide member 44 is provided with a rotatable support portion such as a pin 59, and an adjustment mechanism including an elongated hole 60 and a locking screw 61 is provided at one end. Each lens 1 has slight variations in its focal length f, and there may be slight differences in position during assembly.The second guide member 44 is designed to always maintain focus against such variations. By finely adjusting the provided adjustment mechanism in the direction of arrow F, the angle θ at which it intersects with the first guide member 41 can be adjusted. A rotatable support part (pin 5
The position 9) is located at the intersection 8 of the hanging straight line 7 from the point 6 of the first straight line 4 to the fulcrum 9 shown in FIG. 2 and the second straight line 5 constituting the second guide member 44. ing.

Furthermore, the operation of the embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 4, when the solenoid 39 is energized, the lever 37 is attracted. At the same time, the drive pulley 25 begins to rotate clockwise as indicated by arrow G. Locking member 3 provided on half-speed support member 22
6 moves slightly to the left and solenoid 39
When energized, the half-speed support member 22 is fitted into the engaging portion 38 of the lever 37 that is lifted upward, thereby fixing the half-speed support member 22 at a fixed position. At the same time as the solenoid 39 is energized, the fifth
The solenoid 51 shown in the figure is also energized. The solenoid 51 is a positioning plate 5 for setting variable magnification.
Due to this suction action, the positioning plate 52 is lifted upward (toward the front) in the drawing, and the fitting with the pin 50 provided on the first slider 42 is released. When the drive pulley 25 rotates in the direction of arrow G in this state, the terminal 31 fixed to the wire 26 moves to the right. Therefore,
Since the first slider 42 moves to the right to a position corresponding to the magnification ratio to be set, the lever 48
The second slider 45 moves, and the movement of the second slider 45 causes the third slider 4 to move.
9 will move in conjunction with each other. As the third slider 49 moves, its terminal 54 moves to the right by the distance calculated by the above formula (), and the wire 55 is wound by the pulley 57 by that amount. Therefore, the third support member 24 fixed to this wire 55 moves to the left,
The third reflecting mirror approaches the lens 1 side,
As explained in detail in FIG. 3, it is possible to set the magnification change so that the image is always in focus.

Then, when it is detected by the output signals from the plurality of sensors 64, 65, and 66 arranged around the encoder disc 63 that the position corresponding to the set magnification ratio has been reached, the energization to the solenoid 51 is cut off. When the pin 50 is fitted into the predetermined hole 53, the current to the solenoid 39 is also cut off.

Since the holding of the half-speed support member 22 is released and it becomes freely movable, the document surface is scanned as the drive pulley 25 rotates, and then, as the drive pulley 25 reverses, it returns to the position before the start of the magnification change operation. In other words, it returns to the original position where scanning started. This completes the preparation for variable size copying.

In the present invention, the half-speed support member 22 and the third
The support member 24 is disposed on the opposite side of the lens 1, and is configured to be guided by the same second guide shaft 23. However, the half-speed support member 22 is Although it moves to the point closest to the lens 1, it is impossible to get over the lens 1, and the third support member 24 also comes closest to the lens 1 when the reduction magnification is the smallest. It will never get past Lens 1. Therefore, even if the same guide shaft is used for sliding, there will be no collision.

The lens 1 is fixed to a lens housing 62 as shown in FIG. 4, and the sixth mirror 18 is also fixed to this lens housing 62 to form a lens housing unit.

Further, an encoder disc 63 is attached to the rotation support part 9, which is the fulcrum of the lever 48, and rotates as the lever 48 swings. It is configured to give a signal. If these plurality of sensors are photo-sensors, the notches 63a, 63b, and 63c provided in the encoder disc 63 turn on and shut off. Therefore, if the magnification ratio is set using the plurality of sensors, and if the power to the solenoid 51 is cut off when the predetermined magnification ratio is detected, the positioning plate 52 for magnification can be placed downward at the predetermined position. The magnification change mechanism can be locked by fitting the magnification change hole 53 with the pin 50 of the first slider 42.

The positioning plate 52 for variable magnification may be provided with a hole or a notch that can be used for a copying machine from reduction to equal magnification to enlargement. In this embodiment, a total of eight holes are provided, including five stages of reduction, two stages of equal magnification, and two stages of enlargement. For example, reduce this by 4 steps and enlarge by 3 steps.
If you want to change the number of magnification steps to the same magnification, you can easily achieve this by changing the position of the hole or the position of the positioning plate.

Further, although a method for driving the drive pulley 25 of the optical system is not shown, in the embodiment of the present invention, a DC motor equipped with a rotational speed detection means is used.

This is so that a pulse is output from the rotation speed detection means according to the rotation speed of the motor, and this pulse is compared with a reference signal from a reference signal generator built into the main body, and the rotation of the motor is determined. If the number of rotations is slow, the motor is controlled to increase its rotational speed, and is controlled so that it always rotates at a constant rotational speed. Further, a plurality of reference signals are prepared according to reduction and enlargement, and an appropriate reference signal is used in synchronization with selection of the magnification of the variable magnification mechanism.

Needless to say, when the optical system returns, a voltage in the opposite direction is applied to the motor, causing the motor to rotate in reverse.

Furthermore, in the embodiments of the present invention, the first reflecting mirror is moved, and in conjunction with this, the third reflecting mirror is moved in accordance with the magnification ratio.
The present invention is not limited to such embodiments; for example, the first reflecting mirror may be fixed and the second reflecting mirror may be moved to the left as shown in FIG. , although the configuration is complicated, the first
It is also possible to change the magnification by simultaneously moving the second reflecting mirror to the right and the second reflecting mirror to the left. The present invention can be achieved by interlocking the distance and the distance between the lens and the third reflecting mirror by a distance corresponding to the magnification ratio.

Effects of the Invention As described above, according to the present invention, even if the focal lengths of the lenses used vary, the focus can be easily adjusted.

In general, even if you try to keep the same focal length of a lens, there are variations in the refractive index of the guide used,
Due to variations in dimensional accuracy, some variation in focal length occurs. If we try to produce a large number of copiers with a variable copying magnification function using such lenses, we will have to shift the mounting position of the lens depending on the variation in the distance between the lenses, or finely adjust the position of the mirror to achieve focus. This has the drawback that the adjustment is complicated and takes too much time.

Furthermore, even if the object is focused at a certain magnification, it does not necessarily come into focus accurately at other magnifications, and in reality, a certain amount of out-of-focus is unavoidable in practical use.

In order to be able to focus at any magnification depending on the magnification of reduction or enlargement, the focal length of the lens should be selected so that it always remains at a constant value.
If a large number of copiers were to be produced under this condition, many lenses would be unusable, making it impractical.

However, in the present invention, by providing an adjustment mechanism that rotatably holds the support plate that supports the guide member that guides the movement of the second slider,
Adjustment of this angle at one point can accommodate variations in the focal length of the lens.

Furthermore, once the angle θ is adjusted in this way, the image will be in focus accurately at any magnification, even if the magnification is changed. As a result, when manufacturing a copying machine, it is no longer necessary to eliminate variations in focal length, making lens selection much easier.In addition, in actual adjustment work, you can only adjust the focus at one magnification and adjust the focus at other magnifications. It has excellent effects such as automatic focusing and very short adjustment time.

[Brief explanation of the drawing]

FIG. 1 is an optical projection diagram for explaining obtaining a reduced image, FIG. 2 is a diagram for explaining the principle of copying magnification conversion according to the present invention, and FIG. 3 is a lens in an embodiment of the present invention. FIG. 4 is a perspective view of a main part of an optical system in an embodiment of the present invention, and FIG. 5 is a plan view of a main part of a copying magnification conversion device according to an embodiment of the present invention. be. 1... Lens, 4... First straight line, 5... Second
straight line, 9... fulcrum, 13... first reflecting mirror, 1
6, 17...Third reflecting mirror, 42...First slider, 44...Second guide member, 45...Second slider, 48...Lever, 59...Support part ( pin),
60...long hole, 61...locking screw.

Claims (1)

[Claims] 1. A first slider that slides on a first straight line, and a second slider that slides on a second straight line that intersects the first straight line at a constant angle θ. and the vertical distance from one point on the first straight line to the second straight line is A, and a fulcrum is provided at a position extending by a distance of A,
A lever is provided to swing the first slider and the second slider about this fulcrum, and the movement distance of the first slider and the distance of the second slider are As the amount of movement, the movement distance in the parallel direction to the first straight line is defined as the movement distance of the first reflecting mirror and the third reflecting mirror, which are arranged to sandwich a lens having a focal length f that performs magnification change, respectively. , the above A, θ and f are expressed as f=
Set it so that the relationship is 2A/tanθ, and
A copying magnification conversion device characterized in that the angle θ at which the first straight line and the second straight line intersect can be adjusted in response to variations in the focal length f of a lens. 2. A rotatable support part is provided on the guide member that guides the movement of the second slider, and an adjustment mechanism is provided to rotate the guide member around this support part to adjust the angle θ formed with the first straight line. 2. A copying magnification conversion device according to claim 1, wherein the copying magnification conversion device is capable of converting a copy magnification.