JPS6235086Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a quick return device for one copying cycle in a copying machine.

Conventionally, a copying machine starts one copying cycle by a print signal issued by operating a print switch, regardless of the size of the original, and ends one copying cycle by exposing a set fixed stroke. ing. Further, it has been proposed to provide a quick return lever as a means for quick return depending on the size of the document. That is, Fig. 1,
As shown in FIG. 2, when setting the original 1 on the exposure table 2 and covering the sheet 3, the operator
Some apparatuses are designed to detect a quick return signal during one copying cycle by setting the quick return lever 4 according to the size of the exposure mechanism, and to return the exposure mechanism to its initial state.

However, in the former case, even if the document 1 is small, the exposure mechanism operates a certain stroke, so there is a so-called meaningless exposure time that does not match the size of the document 1, and the machine cannot fully utilize its capabilities. It had no drawbacks. On the other hand, the latter method is superior in that it can omit meaningless exposure time and relatively increase copying speed. However, this operation has the problem that the operator has to manually set the quick return lever 4 according to the size of the document 1, and also requires a mechanical means to generate the quick return signal. There were also drawbacks such as a problem with the return lever.

Furthermore, conventionally, in addition to the above-mentioned method, it has also been considered to optically detect the size of the document placed on the exposure table to automatically control the operation of the exposure mechanism according to the size of the document. The document size detection device in this case detects the size of the document by emitting light in the direction of the document set on the exposure platform and the sheet covering the document, and receiving the reflected light. On the other hand, if the original is thin, the sheet 3 can be brought into contact with the outer surface of the original 1 as shown in FIG. On the other hand, if the original is thick,
As shown in FIG. 3, it is difficult to bring the sheet 3 into contact with the side surface of the original 1', and the sheet 3 becomes wavy, creating a large space 35 between the sheet 3 and the original 1'. For this reason, if the original is thick, the original size detection device cannot accurately receive the reflected light corresponding to the original size from the reflective plate of the sheet. I was unable to obtain the full effect of increasing the speed.

The present invention was made in view of the above circumstances,
The purpose is to accurately detect the size of the document without being affected by the thickness of the document.
The operation of the exposure mechanism can be automatically controlled,
Therefore, it is an object of the present invention to provide a copying apparatus that can reliably increase the overall copying speed.

An embodiment of the present invention will be described below with reference to FIGS. 4 to 8. In the figure, 20 is a main body of the copying apparatus, and an optical detection device 21 consisting of a light projecting section 21a and a light receiving section 21b is arranged at a predetermined position within this main body 20. Reference numeral 22 denotes a movable exposure table provided on the upper part of the main body 20 and made of a transparent member for placing the original 23; 24 denotes the exposure table 2;
This is a reference frame formed of a magnetic member for positioning the document 23 placed on the document 23. Also,
25 is pivotally connected to one end of the exposure table 22 and
A rotatable sheet 26 covering the photodetector 2 is a reflecting plate provided on the lower surface of the sheet 25 on the exposure table 22 side and fixed at a position facing the optical detection device 21 . Note that 27 is an outlet for connecting the entire device to a power source.

Furthermore, 28 is a preset dial for specifying the number of copies, 29 is a print switch for issuing copy commands, and 30 is for turning on and off the power of the entire device.
31 is a main motor serving as a drive source for each mechanism; 32 is electrical equipment such as various lamps and fans; 33 is a drive system driven by the motor 31; 34 is connected to the drive system 33; This is the exposure equipment that was used.

Next, the operation of the present invention based on the above configuration will be explained. First, by plugging the outlet 27 into the power source and turning on the main switch 30 to turn on the power, the electrical components 32 such as various lamps and fans and the optical detection device 21 are put into operation and on standby. Therefore, the side edges of the original 23 are brought into contact with the reference frame 24 and placed on the exposure table 22. Next, if two or more copies of the same document 23 are required, the required number of copies is determined by operating the preset dial 28, and the print switch 29 is operated. At this time, if one copy of the same document 23 is to be made, the print switch 29 is operated immediately without operating the preset dial 28.

Then, by operating the print switch 29 and preset dial 28, hold once,
Alternatively, a print signal that is held a required number of times is generated, and the optical detection device 21 starts operating based on this print signal. Then, the copying cycle starts immediately, but at the start of the operation, the light emitted by the light projecting section 21a of the optical detection device 21 is blocked by the document 23 placed on the exposure table 22, and the reflected light enters the light receiving section 21b. Therefore, it is confirmed that the original 23 is still placed on the exposure section 22. (See 1A in FIG. 5 and FIG. 6.) Thus, as the copying cycle progresses and the rear end of the document 23 reaches near the exposure section 22, the document 23 receives the light emitted from the light projecting section 21a without being blocked. It is displaced to a position where the reflected light is incident on the portion 21b. (See 1B in FIG. 5) At this time, the light receiving section 21a of the optical detection device 21 changes from "dark" to "bright", indicating that the rear end of the document 23 is located near the exposure section 22. confirm. Then, the light receiving section 21b immediately sends a return signal to the drive system 33 to control the exposure device 34, and the exposure table 22 is moved to the left in FIG.

In this way, the exposure table 22 returns to its initial position, completing one copying cycle and waiting until the next print signal is issued. Note that when the size of the document 23 is the maximum size that matches the dimensions of the exposure table 22, the exposure table 22 moves to the maximum stroke (to the position of point X in FIG. 4) and exposes. It returns to the initial position by a return signal issued from a control section (not shown).

Next, the original 23, the sheet 25 and the reflector 2
6 will be explained in detail. As shown in FIG. 7, the sheet 25' has a core 36 made of a rigid needle material with a semicircular cross-sectional diameter, and a thin plate 37 of highly elastic and reflective magnetic material is attached to the exposure table 22 side. is possible.

When the sheet 25' is covered with a thick original 23', the sheet 25' exhibits a wavy state along the outer surface of the original 23', and the thin plate 37 is attached to the exposure table 23'.
Reference frame 24 made of magnetic material fixed to the side edge of 2
Since the document 23' is attracted to the document 23', a large space is not formed on both sides of the document 23', and the light emitted from the light emitting unit 21a is Since the original 23' is located at a position where the
By reliably recognizing the rear end, the exposure table 22 can be returned to its initial position without unnecessarily operating it.

As explained above, according to the present invention, the size of the document can be accurately detected and the operation of the exposure mechanism can be automatically controlled without being affected by the thickness of the document set on the exposure table. Therefore, it is possible to provide a copying apparatus that can reliably increase the overall copying speed depending on the size of the document.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional copying device, FIG. 2 is a partial cross-sectional view showing the relationship between the positions of sheets and originals in the same device, and FIG. 3 is a perspective view of the relationship between sheets and thick originals in the same device. 4 is a perspective view of a copying machine showing an embodiment of the present invention, FIG. 5 is a schematic circuit diagram showing the structure of the same device, and FIG. 6 is an optical diagram of the same device. FIG. 7 is a partial cross-sectional view of the target detection device; FIG. 7 is a partial cross-sectional view showing the relationship between a sheet and a thick document in the device;
The figure is a partially enlarged sectional view showing the positional relationship between a thick original, an exposure table, and a reflecting plate in the apparatus. 22...Exposure table, 23, 23'...Original, 21
...Optical detection device, 25, 25'...Sheet, 2
1a...Light emitter, 21b...Light receiver, 26...Reflector.

Claims (1)

[Scope of utility model registration request] a copying apparatus main body; an exposure table provided along one outer peripheral surface of the main body for exposing a document placed thereon;
an optical detection device that is provided inside the main body and that optically detects the length of at least one of the originals placed on the exposure table; a sheet that covers the original, and a reflective plate that is provided on the exposure table side of this sheet and is made of a thin elastic plate and that allows light emitted from the light projecting section constituting the optical detection device to enter the light receiving section. and an adsorption member provided on a side edge of the exposure table to magnetically attract the reflecting plate to the exposure table in a state in which the reflecting plate is deformed along with the outer shape of the document together with the sheet, during one copying cycle. A copying apparatus characterized in that an exposure operation on the exposure table is controlled according to the size of the document.