JPH03107274A - Image reader - Google Patents

Abstract

PURPOSE:To simply attain focus adjustment by providing an arithmetic means which obtains distances to a first and a second optical systems, at least, on the basis of detection timing outputted from a first and a second position sensors, and calculates error distance. CONSTITUTION:The first and the second optical systems 3, 6 are moved by a scanning means. At that time, it is detected by the first position sensor 16 fixed to a device main body at the position determined beforehand for an imageing lens 22 that the first optical system 3 arrived at its position. Besides, it is detected by the second position sensor 17 fixed to the device main body at the position determined beforehand for the lens 22 that the second optical system arrived at its position. Then, the distance from the sensor 16 to the sensor 17, at least, is obtained on the basis of the detection timing outputted from these sensors 16 and 17, and the error distance is calculated by the arithmetic means 23. Then, the obtained error distance is displayed by a display means 24. The fitting adjustment of a wire is executed by observing the displayed error distance. Since the error distance can be recognized in terms distance, the adjustment can be simply completed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image reading device used in a copying machine or the like.

[Prior Art] Document reading in a conventional copying machine is performed as follows.

That is, as shown in FIG. 5, the first optical system 3 includes a lamp l for irradiating light onto the original, a mirror 2 for guiding light reflected by the original in a predetermined direction, and the like. A second optical system 6 including a mirror 4.5 for guiding light emitted from the image forming lens to an imaging lens is moved along the document and scanned to read the document.

By the way, as shown in FIG. 5, in order to move the first optical system 3 and the second optical system 6 in this way, the first optical system 3 and the second optical system 6 are fixed to the wire 7, and the first optical system 3 and the second optical system 6 are fixed to the wire 7. wire 7
is suspended on a pulley 8, and the wire 7 is moved by rotating the drive shaft 9.

However, during movement, the wire 7 may come off the pulley 8 or break for some reason.

In that case, the wire 7 may be re-hanged or a new wire 7 may be set.

[Problems to be Solved by the Invention] At that time, the distances between the first optical system 3 and the second optical system 6 with respect to the imaging lens change due to the adjustment or resetting of the hook.

Therefore, conventionally, after adjusting the hanging, copying is performed, and the copied image is checked to see if it is in focus, and if it is not,
Adjust the screw of the fixing part 10 for fixing the first optical system 3 to the wire 7, adjust the position to attach it to the wire 7, perform copying again, inspect the image, and then Check whether the adjustment is correct. Therefore, adjusting the focus is very troublesome and time consuming.

SUMMARY OF THE INVENTION In view of the problems of the prior art, it is an object of the present invention to provide an image reading device that can easily adjust focus in a short time when adjustment is necessary, such as when a wire comes off.

[Means for Solving the Problems] The present invention includes a first optical system including a light source that irradiates light onto a document placed on a document placement plate, and an image forming system using image light from the first optical system. In the image reading device, the image reading device includes a second optical system having a mirror or the like that guides the image to the lens, and a scanning means for moving and scanning the first and second optical systems along the document mounting plate. a first position sensor fixed to the apparatus main body at a predetermined position relative to the image forming lens, and detecting that the first optical system has reached the position; and a first position sensor fixed to the apparatus main body at a predetermined position relative to the imaging lens; a second position sensor that is fixed to the apparatus main body and detects that the second optical system has reached its position;
When the optical system is moved, at least the distance from the first optical system to the second optical system is obtained based on the detection timing output from the first position sensor and the second position sensor, and an error distance is calculated. This image reading device includes a calculation means for calculating the error distance, and a display means for displaying the obtained error distance.

[Operation] According to the present invention, the first and second optical systems are moved by the scanning means, and at that time, the first position sensor fixed to the apparatus main body at a predetermined position with respect to the imaging lens is used to move the first and second optical systems. 1
Detecting that the optical system has reached that position, and also detecting that the second optical system has reached that position by a second position sensor fixed to the apparatus main body at a predetermined position with respect to the imaging lens. The distance from the first position sensor to the second position sensor is obtained by the calculating means based on the detection timing output from the first position sensor and the second position sensor, and the error distance is calculated. calculate. Then, the obtained error distance is displayed by the display means. Check the displayed error distance and adjust the wire attachment. Since the error can be known from the distance, the adjustment can be completed very easily.

[Examples] The present invention will be described below with reference to drawings showing examples thereof.

FIG. 1 is a perspective view showing an embodiment of an image reading device according to the present invention.

In this figure, members similar to those of the image reading device shown in FIG. 5 are given the same reference numerals.

That is, as shown in FIG. 1, a first optical system 3 includes a lamp 1 for irradiating light onto a document (not shown), a mirror 2 that guides light reflected by the document in a predetermined direction, and the like. 1
A mirror 4 that guides the light coming out of the optical system 3 to the imaging lens.
5 and the like is moved along the document and scans the document to read the document.

The first optical system 3 is fixed to the wire 70 by screwing using a presser plate 10. By adjusting this presser plate IO, the position of attachment to the wire 70 can be adjusted.

One end of the wire 70 is fixed to the wire stopper 11, and the other end is suspended from a pulley 81 which is pivotally supported by the second optical system 6. The wire 70 is further suspended from a pulley 82 located below the wire stopper 11, and is driven. It is wound around a drive roller 90 fixed to a shaft 9.

On the other hand, the wire 71 has one end fixed to the wire stopper 12 via the spring 13, the other end suspended from the pulley 81 of the second optical system 6, and further via the pulley 83.
It is wound around the drive roller 90.

The driving roller 90 and wires 70 and 71 constitute a scanning means.

As shown in the figure, a detected portion 14 having a protrusion is attached to one end of the first optical system 3.

Therefore, this detected portion 14 moves in the same manner as the first optical system 3 moves. Similarly, a detected portion 15 having a protrusion is attached to one end of the second optical system 6. Therefore, this detected portion 15 moves in the same manner as the second optical system 6 moves.

On the other hand, in the middle of the movement of the detected part 14, a first
A position sensor 16 is arranged.

Similarly, a second position sensor 17 for detecting the movement of the detected part 15 is arranged at a predetermined position, which will be described later, during the movement of the detected part 15.

The first position sensor 16 is, for example, an optical sensor, in which a light emitting element 161 is arranged in the upper stage and a light receiving element 162 is arranged in the lower stage, and the detected part 14 is arranged between the light emitting element 161 and the light receiving element 16.
By passing between 2 and 2, the light can be blocked and its passage can be detected. Similarly, the second position sensor 17 is, for example, an optical sensor in which a light emitting element 171 is arranged in the upper stage and a light receiving element 172 is arranged in the lower stage.
By passing between the two, it is possible to block the light and detect its passage. Further, in the same embodiment, a third position sensor 18 is provided at a so-called home position, which will be described later. This third position sensor 18 is for detecting passage of the detected portion 14 of the first optical system 3, and has a similar structure to the first position sensor 16. That is, it is an optical sensor,
A light emitting element 181 is arranged in the upper stage and a light receiving element 1B2 is arranged in the lower stage, and the detected part 14 is arranged between the light emitting element 181 and the light receiving element 1.
82, the light can be blocked and its passage can be detected.

FIG. 2 is a schematic cross-sectional view of the embodiment of the image reading device shown in FIG. 1, centering around the first optical system 3, second optical system 6, and the position sensor. In the figure, 20 is a manuscript, 21
is a document placement plate on which the document 20 is placed. Further, P is image light, and 22 is an imaging lens.

The first position sensor 16 is fixed to the main body of the apparatus at a predetermined position with respect to the imaging lens 22, and detects when the first optical system 3 has reached that position. Further, the second position sensor 17 is fixed to the main body of the apparatus at a predetermined position with respect to the imaging lens 22, and detects when the second optical system 6 reaches that position. .

These predetermined positions are determined by the calculation means 23 described below.
It is determined based on the content of the calculation.

The calculation means 23 operates when the first and second optical systems 3.6 are moved by the wires 70, 71 of the scanning means, etc.
This is means for obtaining at least the distance from the first position sensor 16 to the second position sensor 17 based on the detection timing output from the first position sensor 16 and the second position sensor 17. It is usually realized using a microcomputer. That is, for example, when the first optical system 3 moves and reaches the position of the first position sensor 16, it is detected and a detection signal thereof is sent to the calculation means 23.

The calculation means 23 uses its internal timer 231 to
The detection timing is memorized.

On the other hand, in the illustrated embodiment, at the detection timing, the second optical system 6 has not yet reached the second position sensor 17, so no detection signal is output. After a while, the second position sensor 17 detects the arrival of the second optical system 6 and outputs a detection signal. The calculation means 23 is
This means uses these two detection timings to obtain the distance between at least the first optical system 3 and the second optical system 6, compares it with the original correct distance, and calculates an error distance.

The display means 24 is a means such as a liquid crystal display that displays the distance calculated by the calculation means 23.

FIG. 4 is a block diagram centered on a computer when the calculations of the present invention are realized by a microcomputer.

Signals from the first position sensor 16, second position sensor 17, and third position sensor 18 are input to a CPU (Central Processing Unit) via an interface 42. Therefore, passage through the first optical system 3 and the second optical system 6 can be known. The CPU 41 performs the calculations based on these detection signals, and also sends a signal to the motor controller 43.
The motor 44 is rotated to control the movement of both optical systems 3.6.

This motor 44 drives the drive shaft 9.

Next, the method of use and operation of the present invention will be explained.

First, the first optical system 3,
A second optical system 6 and an imaging lens 22 are arranged. At that time, adjustments are made while actually copying, as in the past.

Further, the third position sensor 18 is placed at the home position. Furthermore, the first position sensor 16 is placed at a predetermined position closer to the document than its home position. Furthermore, when the first optical system 3 reaches the first position sensor 16, the second position sensor 17 is placed at a predetermined position closer to the document than the position where the second optical system 6 is present.

Then, the first optical system 3 and the second optical system 6 are caused to scan at a predetermined speed. As a result, the time difference between the detection timing output from the first position sensor 16 and the detection timing output from the second position sensor 17 can be found. Since the scanning speed is constant, the distance between the first optical system 3 and the second optical system 6 can be calculated from the time difference. Since this distance is correct, it is stored in the calculation means 23.

On the other hand, if the wire 70.71 comes off, the user rehangs the wire 70.71 and sets the copying machine to the adjustment simulation mode.

FIG. 3 is a flowchart showing subsequent operations.

By rotating the drive shaft 9 in reverse, the wires 70, 71 move in the direction opposite to the direction of the arrow, and the first optical system 3,
The second optical system 6 moves (step S2). When the first optical system 3 is detected by the third position sensor 18, in step Sl), the first optical system 3 and the third optical system 6 are moved by 100 m.
It is moved in the direction of the arrow at m/sec (step S3).

When the first position sensor 16 detects the first optical system 3 (step S4), the signal is inputted to the calculation means 23. At that point, the calculation means 23 clears the timer 231 and starts (step S5).

When the second position sensor 17 detects the second optical system 6 (step S6), the detection signal is manually input to the calculation means 23. The calculation means 23 compares the count value of the timer 231 with the originally correct time value and outputs the difference as an error signal. For example, the timer 231 is 1 m5ec
It counts 1 per time, and the scanning speed is l Q Q
If mm/see, 1 count is 0, 1
This corresponds to mm.

Therefore, even if the error time-opening value is output as it is, a value that can be regarded as a distance is output.

Of course, the actual distance may be output by multiplying the time by 0.1. It is sufficient if the operator knows these circumstances in advance from a manual or the like.

The display means 24 displays the error distance (step S7
).

After the detection by the second optical system 6, both optical systems 3 and 6 are further switched to 1.
It is moved forward by sec (step S8).

After that, the first and second optical systems 3.6 are moved backwards (
Step S9).

When the third position sensor 18 detects the first optical system 3 (step S10), the first and second optical systems 3.6 are stopped at that position (step 5ll).

After that, the worker recognizes the error distance and adjusts accordingly.
The attachment position of the first optical system 3 to the wire 70 is adjusted by adjusting the screw of the presser plate IO. By doing so, the focus can be adjusted with -times of adjustment.

Note that the first optical system 6 is located at a position where the second optical system 6 is detected immediately at the detection timing of the first optical system 3.
Although the position sensors 16 and 17 may be arranged, in order to make it easier to perform normal calculations, as in the above embodiment, the second
It is desirable to arrange the optical system 6 so that it can be detected.

Further, instead of performing the above calculation, the calculation means may output the distance between the first optical system 3 and the second optical system 6 as is. In that case, the worker
The correct distance known in advance may be compared with the output distance, and the error may be calculated and adjusted by the user himself.

[Effects of the Invention] As described above, the image reading device according to the present invention provides detection output from the first position sensor and the second position sensor when the first and second optical systems are moved by the scanning means. Based on the timing, the distance to at least the first optical system and the second optical system is obtained, and a calculation means is provided to calculate the error distance, so the operator can easily adjust the focus using the error distance. I can do it.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of an image reading device according to the present invention, FIG. 2 is a schematic sectional view of the embodiment, and FIG. 3 is a flowchart showing the operation of the embodiment. Figure 4 is
FIG. 5 is a block diagram showing an example in which a computer is used in the same embodiment, and FIG. 5 is a perspective view of a conventional image reading device. 1... Light source 2.4.5... Mirror 3... First
Optical system 6...Second optical system 70.71...Wire
16...First position sensor 17...Second position sensor
2o...Original 21...Original placement plate

Claims (2)

[Claims] (1) A first optical system that includes a light source, etc. that irradiates light onto the original placed on the document placement plate, and a second optical system that includes a mirror, etc. that guides the image light from the first optical system to an imaging lens. In the image reading apparatus, the image reading apparatus includes a scanning means for moving and scanning the first and second optical systems along the document mounting plate, at a predetermined position with respect to the imaging lens. a first position sensor that is fixed to the main body and detects that the first optical system has reached its position; and a first position sensor that is fixed to the main body of the apparatus and detects that the first optical system has reached its position; The second one detects that the system has reached that position.
When the first and second optical systems are moved by the position sensor and the scanning means, at least the first to second optical systems are moved based on the detection timing output from the first position sensor and the second position sensor. An image reading device comprising: a calculation means for obtaining a distance to an optical system and calculating an error distance; and a display means for displaying the obtained error distance. (2) A claim characterized in that when the first optical system is detected by the first position sensor, the second position sensor is placed a predetermined distance away from the position where the second optical system should originally exist. Item 1. Image reading device according to item 1.