JPS63218932A - Variable power optical device - Google Patents

Abstract

PURPOSE:To necessitate no special jig nor tool, and to simplify adjusting work by executing a correction of a reference position of a lens and a mirror, respectively, by inputting a correction value from the outside. CONSTITUTION:While confirming a copying magnification at the time of manufacturing a copying machine, the number of correction steps is determined by confirming whether a projection lens 5 and conjugate length correcting mirrors 3, 4 can be set to an exact unmagnification position or not by how many steps stepping motors M1, M2 are rotated from a position where the stepping motor M1, M2 have stopped by a fall signal outputted from a sensor 15 and a sensor 2. Subsequently, the number of these correction steps is set to a dip switch connected to a CPU, as a lens position correcting signal and a mirror position correcting signal. Thereafter, these correcting signals are always inputted to the CPU, as a fixed value. In such a way, it is unnecessary to correct the unmagnification position of the lens 5 and the mirrors 3, 4 by a mechanical means.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical device used in a copying machine or the like that can change the copying magnification, and particularly relates to correction of the same-magnification positions of lenses and mirrors.

[Conventional technology]

Copying machines equipped with magnification changing devices that can arbitrarily set the copying magnification are becoming popular, but in order to change the copying magnification, it is necessary to change the positions of the lenses and mirrors that make up the scanning optical system. .

To change the copying magnification, the position of the optical system for full-size copying is used as a reference position, and the amount of movement from there to the position corresponding to the copying magnification is determined by the number of steps of the stepping motor that moves the lens, and the step is moved by a microprocessor. In addition, a cam mechanism was used to move the mirror in conjunction with the movement of the lens, and the mirror was moved in accordance with the movement of the lens corresponding to a predetermined magnification.

For this reason, when adjusting the position of the optical system to match the copying magnification that is performed when manufacturing or repairing a copying machine, the position where the copying magnification is 1x is set as the reference position and the lens and mirror positions are corrected. In this case, in order to correct the position of the lens, the step number correction value of the stepping motor is input externally to the optical system control microprocessor using a dip switch, and in order to correct the position of the mirror, the spatial magnification While confirming the magnification using a confirmation device, the adjustment mechanism provided on the mirror drive member driven by the cam mechanism was adjusted using a jig.

[Problem that the invention seeks to solve]

On the other hand, in order to meet the demand for large copies such as drawings, AI
There is a large-sized copying machine capable of making copies of A2 size, A2 size, etc., but this type of copying machine is required to have a wider range of change in copying magnification than conventional small-sized copying machines.

As the range of change in copying magnification expands, the range of movement of the lens and mirror also expands, but at this time, the range of movement of the lens and the movement of the mirror partially overlap, so the cam shape must be adjusted to prevent the mirror from colliding with the lens. In addition to being extremely difficult to design, depending on the cam shape, the range of load fluctuation when changing the magnification is significantly expanded, requiring a large drive mechanism. For this reason, the present applicant has previously filed an application in which the lens and mirror are provided with independent drive mechanisms and these are controlled by a microprocessor (Japanese Patent Application No. 60-274338, Japanese Patent Application No. 60-60). -274339).

However, it is still necessary to adjust the position of the optical system to match the copying magnification during manufacturing and repair of copying machines, and the drive mechanisms for lenses and mirrors are provided independently. It is necessary to correct the position.

[Means for solving problems]

In order to solve the above-mentioned problems, this invention corrects the reference positions of each lens and mirror by inputting correction values from the outside. The apparatus includes a first driving means for changing the lens position, a second driving means for changing the mirror position, a first position detection means for detecting the reference position of the lens, and a first driving means for detecting the reference position of the mirror. a first correction signal input means for correcting the reference position of the lens; a second correction signal input means for correcting the reference position of the mirror; The corrected reference position of the mirror is corrected by the correction signal and outputted to the first driving means to set the lens at the corrected reference position, and the detected reference position of the mirror is corrected by the second correction signal and outputted to the second driving means. The present invention is characterized by comprising a control means for setting the mirror to a corrected reference position.

[For production]

The reference positions of the lens and mirror detected by the first and second detection means include assembly errors, but this error is input as a correction signal from the outside and output to the first and second drive means, and the lens and mirror are Set the mirror to the correct reference position.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 shows the basic configuration of the optical system and its driving section of a copying machine embodying the present invention, in which 1 is a photosensitive drum, 5 is a projection lens, and is provided on a first slider 10. . 2 is a first mirror fixed to the main body of the apparatus, 3 is a second mirror, and 4 is a third mirror, and the second mirror 3 and the third mirror 4 are mirrors that correct the conjugate length of the scanning optical system. , are integrally assembled on the second slider. The first slider 10 and the second slider move in the optical axis direction according to the set copying magnification. The details will be explained later.

6 is a fourth mirror fixed to the main body of the device. 7 is an exposure lamp, and 9 is an exposure slit provided on the upper surface of the main body of the apparatus. Reference numeral 8 denotes a document glass provided on a document table (not shown) that moves left and right on the upper surface of the main body of the apparatus. 15 is a projection lens equal magnification position detection sensor, and Sae is a conjugate length correction mirror (
(second and third mirrors) are equal-magnification position detection sensors.

The scanning of a document by the copying machine optical system described above is well known and need not be explained again, but its outline is as follows.

When the original OG is placed at a predetermined position on the original glass 8 and a print button on an operation panel (not shown) is pressed, the original glass returns to the scanning starting point. The exposure lamp 7 is turned on, and the light passes through the slit 9 and illuminates the original on the original glass 8. The light reflected from the original OG enters the first mirror 2 through the slit 9, and further passes through the second mirror 3, the third mirror 4, the projection lens 5, and the fourth mirror 6, and forms an image on the photosensitive drum 1. The main motor M3 rotates the photosensitive drum 1 at a constant speed and moves the document glass 8 in the scanning direction at a constant speed corresponding to the copying magnification, thereby scanning the document.

The copying magnification is changed according to the set copying magnification using the projection lens 5 and the second and third mirrors 3 which are conjugate length correction mirrors.
, 4 are moved. This mechanism will be explained below.

FIG. 2 shows the configuration of the first slider 10 provided with the projection lens 5. As shown in FIG. In the figure, Ml is a stepping motor that moves a drive wire 13 in the direction of the arrow via a gear mechanism 12. Since the drive wire 13 is fixed to the first slider 10, it moves along the guide 14 and moves the projection lens 5 in the optical axis direction. In order to detect the same magnification position of the projection lens 50, a light shielding plate 16 is provided on the first slider 10, and a projection lens same magnification position detection sensor 15 consisting of a light emitting diode and a photodiode is provided on the apparatus main body side.

Then, the light shielding plate 16 enters the optical path where the light projected from the light emitting diode enters the photodiode, and the sensor 15
The relative positions of the light shielding plate 16 and the sensor 15 are set so that the position of the light shielding plate at which the output changes from "H#" to "L", that is, the position of the projection lens, can be detected as the same magnification position of the projection lens 50.

Figure 3 shows the second and third mirrors 3, which are mirrors for conjugate length correction.
, 4 is shown. In the figure, the second mirror 3 and the third mirror are attached to the second slider at a predetermined angle.

M2) is a stepping motor that moves the drive wire in the direction of the arrow B via a gear mechanism n. Since the drive wire B is fixed to the second slider, it moves along the guide U and moves the second mirror 3 and the third mirror 4 in the optical axis direction. In order to detect the same-magnification positions of the second mirror 3 and the third mirror 40, a light-shielding stone is provided on the second slider, and a conjugate length correction mirror consisting of a light emitting diode and a photodiode is installed on the main body side of the device. A position detection sensor is provided. and the position of the light shielding plate where the light projected from the light emitting diode enters the optical path where it enters the photodiode and the output of the sensor 24 switches from "H" to "L#";
That is, the light shielding plate part and the sensor 24 are arranged so that the positions of the second and third mirrors 3 and 4 can be detected as the same magnification position of the conjugate length correction mirror.
The relative position of is set.

FIG. 4 is a block diagram of the copying machine, lens, and mirror control circuit, showing the projection lens 5, conjugate length correction mirror 3,
Only the portion related to the detection and correction of the 40-magnification position is shown.

30 is a CPU for controlling the copying machine, and 31 is a CPU for controlling lenses and mirrors. The CPU 30 controls the entire copying machine, and its input board a has various key switches and control sensors arranged on an operation panel (not shown) for controlling the number of copies, copy magnification, print commands, etc. A matrix 35 is connected to the output port Oa, and a main motor M3 for driving a photosensitive drum, a document table, etc. is connected via a motor driver 34. CPU 3
Needless to say, other equipment related to the copying operation is connected to 0. The CPU 31 controls the positions of the projection lens 5 and the second and third mirrors 3 and 4, which are conjugate length correction mirrors, according to the copying magnification input from the key matrix connected to the CPU 30. Correction control is performed for the equal magnification positions of the second and third mirrors 3 and 4, which are conjugate length correction mirrors. A stepping motor M1 that drives the first slider 10 is connected to the output port O□ via a motor driver 32, and a stepping motor M2 that drives the second slider is connected to the output port 02 via a motor driver O. be done.

The input port is equipped with a projection lens equal-magnification position detection sensor 15.
is connected to the input boat 2, and a conjugate length correction mirror equal magnification position sensor 24 is connected to the input boat 2. Further, a dip switch is connected to the input port r3 for inputting a lens position correction signal, and for inputting a mirror position correction signal to T.

For example, between the CPU 30 and the CPU 31, the copy magnification inputted to the CPU 30 from the key matrix section is transmitted to the CPU 30.
For transmission of various control signals such as transmission to U31 C
A signal line is connected from the output port Ob of the CPU 31 to the input port 5 of the CPU 31, and a signal line is connected from the output port 03 of the CPU 31 to the input port 5 of the CPU 30 for transmitting various control signals such as the completion of setting the copy magnification. , the signal line is connected to.

Next, correction of the same magnification positions of the projection lens 5 and the second and third mirrors 3 and 4, which are conjugate length correction mirrors, will be explained.

When the power is turned on, initial setting processing of the CPU 31 is performed, and the copying magnification is set to equal magnification. The stepping motor Ml is connected to the first slider 1 under the control of the CPU 31.
Move 0. The light shielding plate 16 of the first slider 10 enters the sensor 15, and the output of the sensor 15 changes from "I-1" to "L".
'', upon receiving the falling signal, the CPU 31 stops the stepping motor M1.

Similarly, the stepping motor M2 moves the second slider under the control of the CPU 31, and the light shielding plate 5 of the second slider enters the sensor area, causing the output of the sensor 24 to become "H".
When the signal is switched from “L” to “L”, the CPU that received the falling signal
31 stops the stepping motor M2.

At this time, the image of the original OG should be projected onto the photosensitive drum 1 at the same magnification, but in reality, it is not always the same size due to assembly errors. Therefore, when manufacturing a copying machine, while checking the copying magnification, first determine how many steps the stepping motor M1. It is confirmed whether the projection lens and the conjugate length correction mirror can be set at accurate same-magnification positions by rotating M2, and the number of correction steps is determined.

Then, the number of correction steps is converted into a lens position correction signal,
It is set in a dip switch connected to the CPU 31 as a mirror position correction signal. Thereafter, these correction signals are always input to the CPU 31 as fixed values, and there is no need to correct the same-magnification positions of the lenses and mirrors by mechanical means.

During normal use of the copying machine, when the power is turned on, the same-magnification positions of the projection lens 5 and the second and third mirrors 3 and 4, which are conjugate length correction mirrors, detected by the sensor 15 and the sensor mount are corrected as described above. The signal is corrected, and then the copying operation begins. Also, when changing the copy magnification, the lens
Using the corrected position of the mirror as a reference, the stepping motor Ml is moved by the number of steps corresponding to the desired copying magnification.
It is possible to set an accurate copying magnification by driving M2.

FIG. 5 is a flowchart showing the lens position and mirror position control process executed by the lens and mirror control CPU 3.

In step P1, initial settings such as clearing the memory and setting initial values are performed, and the process moves to step P2 to wait for an instruction to start the copying machine control CPU 30.

When a startup instruction is given, the process moves to step P3 and subsequent steps, and the projection lens 5 is first moved to the same magnification position detected by the sensor J5, and corrected using the lens position correction signal (steps P3 and P4). Next, the second and third conjugate length correction mirrors
The mirrors 3 and 4 are moved by the same magnification position button detected by the sensor 24, and corrected using the mirror position correction signal (step P5.
P6). Since the setting to the same magnification position is completed, a setting completion signal is output to the CPU 30 (step P7). CPU 3
Step P to receive the copy magnification signal set from t).
8), determine whether there is a change in magnification (step P9)
When changing the magnification, the process moves to step PLO, and the lens and mirror are moved based on the previously corrected lens and mirror positions according to the set copying magnification. When the movement is completed, and when there is no change in magnification in step P9, the process moves to step pH, transmits a copy magnification setting completion signal to the CPU 30, and returns to step P8 to receive the next signal.

In the above description of the embodiment, the same-magnification positions of the lenses and mirrors are determined when the output signal of the sensor 15.24 changes from H" to "
The sensor 15.L'' is detected when the light is switched to L'', but this is the case, for example, when the light-shielding plate is moving from the reduction magnification to the enlargement magnification.If the light-shielding plate moves in the opposite direction, the sensor 15.
The output signal of No. 24 is switched from "L" to "H". In this case, once it is passed through, it is moved in the opposite direction and the output signal is "H".
The switching from "to L" is detected. This makes it possible to eliminate backlash in the lens and mirror drive mechanisms.

Furthermore, in the above embodiment, the lens position correction signal and the mirror position correction signal are set using dip switches, but the RAM
You can also use .

〔Effect of the invention〕

As explained above, according to the present invention, the correction of the same magnification position of the projection lens and the conjugate length correction mirror is simply performed by the control CPU.
This can be carried out by simply inputting correction values into the system, and no special tools are required. Furthermore, readjustment of the optical system is required when replacing or repairing the projection lens or mirror for conjugate length correction, but even in this case it can be done by inputting correction values, making adjustment work extremely easy. be able to.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the basic configuration of a copying machine embodying the present invention, FIG. 2 is a perspective view showing the configuration of the first slider,
FIG. 3 is a perspective view showing the configuration of the second slider, FIG. 4 is a block diagram of the copying machine, lens, and mirror control circuit, and FIG. 5 is a flowchart showing the control process in the lens and mirror control CPU. 1: Photosensitive drum, 2: First mirror, 3: Second mirror,
4: Third mirror, 5: Projection lens, 6: Fourth mirror, l
O: first slider, 20: second slider, 15: lens equal-magnification position detection sensor, 24: mirror equal-magnification position detection sensor for conjugate length correction. Patent applicant: Minolta Camera Co., Ltd. Figure 1]b Figure 2T Figure 3

Claims (1)

[Claims] In an optical device that can change magnification and is composed of a lens and a mirror, the first driving means changes the lens position, the second driving means changes the mirror position, and the first position detects the reference position of the lens. a detection means, a second position detection means for detecting the reference position of the mirror, a first correction signal input means for correcting the reference position of the lens, and a second correction signal input means for correcting the reference position of the mirror. , the detected lens reference position signal is corrected by a first correction signal and outputted to the first driving means to set the lens at the corrected reference position, and the detected mirror reference position is corrected by a second correction signal. 1. A variable magnification optical device comprising: a control means for correcting the corrected image and outputting it to the second driving means to set the mirror at the corrected reference position.