JPH0446285Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> The present invention is a method of placing and moving a copy original in order to optically scan the copy original and expose the photoreceptor to an image. Regarding copying machines.

<Prior Art> Generally, in a copying machine with a movable document table, part or all of the optical system is provided near the bottom surface of the document table. Since this optical system scans and exposes the copied original on the original platen by moving the original platen, it is designed so that the original can be moved to an extent that is slightly longer than the length of the original, and within that range. It is driven back and forth.

Stoppers and the like are provided at the front and rear of the document table to prevent deviation within the movement range.

<Problems to be Solved by the Invention> The movement range of the document table is determined, for example, by the maximum length of the document, and a stopper or the like is provided to prevent the document table from slipping off. Therefore,
It is not easy to maintain the copying machine, for example, to clean the optical system located under the document table. In other words,
Since the optical system is covered by the document table and the movement range of the document table is restricted by a stopper or the like, the optical system will not be exposed as it is.

Therefore, it is conceivable to remove the document table from the top of the copying machine body and expose the optical system for cleaning or the like. However, in order to remove the document table, very troublesome work is required, such as removing a stopper or the like that restricts the movement range of the document table, and removing the document table from a moving mechanism that moves the document table. Also, once maintenance of the optical system etc. is completed,
The work to return the document table to its original state is also extremely troublesome, as is the work to remove it.

SUMMARY OF THE INVENTION An object of the present invention is to provide a copying machine that facilitates maintenance such as cleaning of an optical system located under a moving document table.

<Means for Solving the Problems> The copying machine of the present invention using the document table moving method is provided with first and second detection means for detecting the position at which image formation on the document table starts and the position at which image formation ends. Means for reciprocating the document table within the range of detection by both detection means is provided, and means for releasably locking the document table in the detection state of the first detection means is provided, and furthermore, the document table is moved between the two detection means. It is characterized by a structure in which the optical system is movable to a position that is outside the movement range of the document table and is exposed.

<Function> According to the present invention, during copying, the document table is driven back and forth within the range for performing image exposure on the photoreceptor by detecting the start and end positions of exposure.
In response to the detection of the start position, image exposure is started and is driven forward, and upon detection of the end position, the exposure is completed and driven backward, and in response to the detection of the start position, it is stopped at that position. Thereby, the image of the placed document can be exposed normally.

On the other hand, the document table is stopped at that position by detecting the starting position, for example, but it is not locked at that position, but is movable outside the detection position, so it cannot be moved to the stopping position. It is possible to move further in the opposite direction to the reciprocating drive direction. Therefore, the optical system located at the bottom of the document table is exposed to the outside, making it possible to perform maintenance, such as cleaning.

<Example> FIG. 1 is a schematic sectional view showing a copying machine according to the present invention.

In the figure, reference numeral 1 denotes a document table movably provided on the main body of the copying machine. The document table 1 holds a document as shown in FIG. 3, and is constructed by covering the front and rear ends of a glass plate 2 with a frame 4. The position of the document table 1 indicated by the solid line in the figure is the starting position for starting exposure, and an illumination device 5 is provided opposite the leading end of the document table 1 for illuminating the document. Next to the illumination device 5, a convergent light transmitting array 7, which is an optical system, is arranged to form a reflected light image from the original onto a drum-shaped photoreceptor 6 that is rotated in the direction of the arrow. . Photoreceptor 6
Various devices for image formation are arranged around the . 8 is a charger for uniformly charging the photoreceptor 6; 9 is a developing device that visualizes the formed latent image; 10 is a transfer device that transfers the visualized image onto paper 11 that is being conveyed as appropriate; Reference numerals 12 and 13 are a static eliminator and a static eliminator lamp that eliminate charges remaining after transfer. After the transfer, the paper 11 is peeled off from the photoreceptor 6, passed through the heat fixing roller 14, and discharged to the outside of the copying machine main body.

In the above-mentioned copying machine, the document table 1 is movably provided on the upper part of the copying machine main body as shown in FIG. 1 via a moving mechanism (not shown). Therefore, during forward movement from the position shown by the solid line on the document table 1, that is, the movement start position, which is the exposure start position, to the overrun position (movement end position) shown by the dotted line, the image of the placed document is transferred to the photoreceptor. 6 through the optical system 7. When the overrun position is detected, the document table 1 is moved back to the movement start position (start position) indicated by the solid line and stopped at that position.

Although not shown, the position of the document table 1 is detected by a document table start position detection means, which is an exposure start position, and an overrun position detection means, and in response to this detection, the document table 1 is moved within that range via a drive means. They are driven. The document table 1 normally starts moving forward from a start position to start exposure, and when this position is detected by the start position detection means, image formation is started. When the overrun position of the forward-moving document table 1 is detected by the detection means, the moving direction is reversed at that point, and the document table 1 is driven backward to the start position, and stopped even when the start position detection means detects the overrun position. be done.

However, according to the present invention, the document table is not locked at the start, but can be easily moved from the start position.

In other words, the document table 1 is provided so that the movement range within the detection range of both of the above-mentioned detection means is not restricted, and it can be freely moved from that position, for example, further to the left side in FIG. It can be moved and the optical system 7 can be exposed to the outside as shown in FIG.

Therefore, the document table 1 according to the present invention is stopped and locked at the start position, that is, in the state detected by the start position detection means, and
A locking means is provided which is a locking mechanism that allows the locking state to be easily released. That is, the locking mechanism is configured so that the document table 1 can be released from the locked state and freely move from the start position. This restraining mechanism includes a restraining member 18 on the document table 1 side and a restraining roller 19 on the copying machine main body side. The locking member 18 is fixed to the frame 3 of the document table 1 as shown in FIGS. 4 and 5, and has a locking recess 181 formed in the center thereof. As you can see, it is formed in a symmetrical shape with that as the center. The restraining roller 19 is rotatably attached to the tip of a mounting plate 22 which is rotatably provided on the copying machine main body frame 20 via a support shaft 21 . On the opposite side of the mounting plate 22 from the restraining roller 19,
Spring 23 with one end fixed to frame 20
is provided to urge the restraining roller 19 upward. This restraining member 18 and the restraining roller 1
Reference numeral 9 indicates that the document table 1 is positioned at a position where the exposure start position of the tip of the glass plate faces the optical system 7, as shown in FIG.
It is attached to each frame body 3 and frame 20.

In the above-described configuration, the document table 1 on the main body of the copying machine is normally held at the document table start position by the restraining mechanism, and forward movement is performed via the drive means when the print button is operated. Begins. At this time, the concave portion 181 of the restraining member 18 that is lightly engaged with the restraining roller 19 is
Release from the locked state.

Subsequently, the document table 1 is driven through a drive mechanism to move forward, and when it reaches the overrun position, it is detected by the overrun detection means, and after reaching the overrun position, the document table 1 starts to be driven back in the opposite direction. be done. When the start position is reached, it is detected by the start position detection means, and the driving of the document table 1 is stopped. At this time, the retaining member 18 and the retaining roller 19 engage with each other, and the document table 1 is stopped at the starting position.

Further, since the document table 1 is lightly stopped at the start position by a restraining mechanism, it is locked in that position and its movement is not restricted, and can be moved further to the left in FIG. 1, for example. That is, if the document table 1 existing at the start position is pushed to the left with a force stronger than the restraining force, the restraint of the restraining member 18 is released and the original table 1 is further moved to the left. This results in
The optical system 7, which was covered by the document table 1, is exposed to the outside and can be maintained, for example, cleaned. After this cleaning, it is sufficient to move the document table 1 toward the start position and to lock the restraining member 18 to the restraining roller 19, thereby ensuring that the document table 1 can be returned to the starting position reliably and easily. At this time, when the copying operation is started, since the document table 1 is positioned at the start position, the copying operation is started without any problem, and there is no loss due to the start of the copying operation.

The above-mentioned copying machine uses a convergent light transmitting body array 7 as the optical system 7, but in this case, a cleaning guide 2 is installed in parallel to the optical system 7 as shown in FIG.
4 is provided, a cleaner 25 as shown in FIG. 6 is moved along this guide 24, and cleaning can be easily performed using a cleaning member 26 at the tip of the cleaner 25. The cleaner 25 has a U-shaped guide portion 251 guided by the guide 24.

Furthermore, it is of course possible to easily clean not only the convergent light transmitting body array but also a reflecting mirror that reflects a reflected light image from an original onto a lens or the like that forms an image.

In the figure, reference numeral 15 denotes a regulating piece, which is provided on the side of the moving document table 1. In addition, 16 and 17 prevent movement to the left from the state shown in FIG. 2 in which the stopper and the document table 1 are moved further to the left from the start position in order to prevent the document table 1 from moving further to the right from the overrun position. This is a stopper to prevent it. That is, in the state shown in FIG. 2, when the optical system 7 is exposed, the regulating piece 1 on the document table 1 side
5 contacts a stopper 17 to prevent further movement, and when the document table 1 moves further to the right than the overrun position, the regulating piece 15 contacts a stopper 16 to prevent further movement. The regulating piece 15 is fixed to the frame 3 of the document table 1, and the stoppers 16 and 17 are fixed to the frame 20 on the copying machine main body side.

Further, the restraining member 18 may be mounted at a different position from the regulating piece 15 or may have a height lower than that of the regulating piece 15 so that the movement of the arresting member 18 is not restricted by the stopper 17.

<Effects> According to the copying machine of the present invention using the document table moving method, during movement for image formation, it is possible to perform reciprocating movement in response to detection by the start position detection and overrun position detection means, so that normal image exposure can be achieved. It can be carried out.

In addition, since the document table is configured to be locked by a removable locking means at the start position where image formation is started, it can be moved out of the range of reciprocating movement from the start position to the end position. Therefore, by moving the optical system to a position where it is exposed, cleaning can be easily performed, making maintenance such as cleaning extremely convenient and simple, and also ensuring that the document table is in the starting position after maintenance. Moreover, it can be easily returned to its original position, and the document table can always be driven back and forth from the starting position.

[Brief explanation of the drawing]

FIG. 1 is a sectional view schematically showing a copying machine using the document table moving method according to the present invention, FIG. 2 is a diagram showing a state in which the document table is moved, and FIG. 3 is a perspective view thereof.
4 and 5 are a side view and a top view showing a specific example of the document table retaining mechanism according to the present invention, and FIG. 6 is a perspective view showing a specific example of the cleaner that cleans the optical system. be. DESCRIPTION OF SYMBOLS 1...Original table, 6...Photoreceptor, 7...Optical means, 18...Retaining member, 19...Retaining roller.

Claims (1)

[Scope of Claim for Utility Model Registration] A copying machine that exposes an image on a photoreceptor by moving a document table with respect to a fixed optical system, comprising: a first detection means for detecting a movement start position of the document table; and the document table. a second detection means for detecting a movement end position of the document table; and a second detection means for detecting a movement end position of the document table; and a second detection means that locks the document table in a detachable state while the movement start position of the document table is detected by the first detection means. a locking means for moving the document table forward from the movement start position of the document table upon the start of copying, and stopping the forward movement of the document table in response to detection by the second detection means and moving the document table in the reverse direction; and stopping the backward movement of the document table in response to the detection by the first detection means, thereby causing the document table to reciprocate between the detection positions by the first and second detection means. a drive means; and a document table that is detachable from the locking means and movable to a position that exposes the optical system outside the reciprocating drive range between the detection positions of both the detection means. A copying machine with a moving document table.