JPS61179430A - Copying machine equipped with device for recognizing original size - Google Patents

Abstract

PURPOSE:To prevent a black frame from being copied and to copy the image at an original end part completely by using a transparent body as an original pressure plate which abuts on an original and providing a movable member which a low-reflection and a high-reflection part at the back surface side of the original pressure plate. CONSTITUTION:When the low-reflection part 28a of the movable member 28 is positioned overlapping with the original 1, the difference between the reflec tion of the ground part of the original 1 through the scanning of illumination lamps 13 and 14 and the reflection of the low-reflecting part 28a of the movable member 28 is passed through the transparent original pressure plate 26 to detect the size of the original 1. Whencopying operation is performed while the mov able position 28 is moved until the high-reflection part 28b is positioned overlap ping with the original 1, the ground part of the original and the high-reflection part are copied uniformly through the transparent original pressure plate 26. Thus, a black frame is prevented from being copied and the image at the end part of the original is copied completely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a copying machine that automatically recognizes the size of a document, then reads the image of the document and performs a copying operation.

[Conventional technology]

For example, in order to recognize the size of a document in a digital copying machine, the pressure plate that holds the document is made black or has a mirror surface to suppress diffused reflection, and the difference in reflection from the white background of the document is detected. Based on the recognized original size, the size of the copy paper is specified, a requested display is displayed, and the range in which the original image is to be read is specified. Therefore, when a copy is made, the original is held against the black original pressure plate. For this reason, if the document is placed on the document table tilted, or if the recognition accuracy is poor and the document is recognized to be larger than its actual shape, the black document pressure plate will also be copied, resulting in a so-called black frame copy in which the edges and corners of the copy are black, which is unsightly. It becomes something.

For example, in FIG. 3, when the original l is placed at an angle, the recognition area 2 becomes wider with respect to the original 1, and the diagonal areas 2a, 2b, etc.
2C fist 2d is copied in black.

In the example shown in FIG. 4, when area 2 is copied from original 1 due to a recognition error, the original image in the shaded area 1a of the original 1 is not copied, and the black of the original pressure plate is copied in the shaded area 2d, resulting in a black frame.

In the example shown in FIG. 5, when the irregularly shaped originals 11 and 12 are copied together, the shaded area 2e is copied in black, and the sixth
In the example shown in the figure, if document 1 has holes g and h, this hole g-
The black color of the document pressure plate is copied through h.

Conventionally, in order to eliminate these drawbacks, a method has been adopted in which the area to be actually copied is narrowed from the recognized original area. However, this method has a major drawback in that images at the edges of the document are not copied.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks and provide a copying machine that can prevent black border copying and can completely copy images at the edges of a document.

[Means for solving problems]

In order to solve the above-mentioned problems, the copying machine of the present invention employs a method in which the document pressure plate that contacts the document is made of a transparent body, and a movable member having a low reflection portion and a high reflection portion is provided on the back side of the document pressure plate. There is.

[Function] By positioning the low reflection part of the movable member so that it overlaps with the original, the difference in reflection between the base part of the original and the low reflection part can be detected through the transparent pressure plate, and the size of the original can be recognized.

If the movable member is moved to position the highly reflective portion so as to overlap the original and a copying operation is performed, the base portion and the highly reflective portion of the original will be uniformly copied through the transparent pressure plate.

〔Example〕

FIG. 1 is a sectional view showing an embodiment of a league portion of a digital copying machine to which the present invention is applied. The apparatus shown in the figure reads an original 1 placed on an original glass 12. The image of manuscript 1 is the illumination lamps 13 and 14 placed inside the National Sports Festival 10,
and a first mirror 15, a second mirror 16, and a third mirror 1.
7. An image is formed on a photoelectric conversion element CCD (charge couple device) 19 by an imaging lens 18, and a CCO
Through the drive circuit 201 and the image processing circuit 21, the output terminal 22
The image signal is then output as an image signal to a printer section (not shown). The illumination lamps 13 and 14, along with the reflectors 23 and 24 and the first mirror 15, move at a constant speed along the document glass 12 to the position shown by the chain line. Second mirror 16, third mirror 17
The illumination lamps 13-14 and the first mirror 15 move at half the speed to the position shown by the chain line, and scan the original. The driving devices for the illumination lamps 13, 14 and the mirrors 15-16, 17 are the same as those used in a well-known copying machine with a fixed document table, so detailed explanations thereof will be omitted.

The case 25 of the document holding unit is connected to the case 10 by a rotatable hinge, and can be opened and closed when setting or removing a document. A transparent document pressure plate 26 is fixedly attached to the case 25. The transparent document pressing plate 26 is made of transparent plastic such as an acrylic plate or a glass plate, and the document glass 12 does not need to have good precision in terms of flatness, thickness, etc.

Inside the case 25, a switching belt 28, which is a moving member, is suspended between rollers 29 and 30 and is located on the back side of the transparent pressure plate 26. The switching belt 28 is a tension roller 31
It's making me nervous.

As shown in FIG. 2 (perspective view), half 28a of the outer periphery of the switching belt 28 is black and the remaining half 28b is white, and the front end of the switching belt 28 has a black mark hole 33a.
However, a blank mark hole 33b is provided at the rear end. The housing 25 (see Fig. 1) has holes 33a and 33, respectively.
Sensors 34a and 34b are provided to detect b.

A drive motor 35 is connected to the roller 30 so that the switching belt 28 rotates.

The drive motor 35 is connected to the controller 3 by a drive circuit 36.
7 signal. The controller 37 is connected to a sequence controller (not shown) of the league.

With the above configuration, when the original 1 is set between the original glass 12 and the transparent original pressure plate 26 and the read key (not shown) is pressed, the motor 35 is rotated by a signal from the controller 37, and the switching belt 28 is rotated. . When the black background mark 33a is detected by the sensor 34a, a signal is output from the controller 37 and the motor 35 is stopped. The switching belt 28 is driven, and the back surface of the transparent document pressure plate 26 becomes a black background portion 28a. Here, a signal is output from the controller 37 to the sequence controller of the league section, and the first mirror 15 and the lighting lamp 13-14
scans from the home position shown by the solid line to the position shown by the chain line, detects and measures the size and position of the document, and when it returns to the home position, a signal is output from the sequence controller to the controller 37. With this signal, the motor 35 rotates again and drives the switching roller 28. When the white mark 33b is detected by the sensor 34b, a signal is output from the controller 37 and the motor 35 is stopped. Then, the transparent original pressure plate 26
The white background portion 28b of the switching belt 28 is located on the back side of the switch belt 28. In this state, a signal is again output from the controller 37 to the sequence controller, and the operation of reading the image of the original l is started.

Only the portion of the document recognized during scanning to measure the document size is read and sent to the printer section as an image signal.

Note that known ones are used for the sequence controller that controls the reader section, the memory that recognizes and stores the document size position, the operation keys, and the like.

〔effect〕

As explained above, according to the copying machine of the present invention, when detecting and recognizing the original size 2, the back of the original and the back of the original can be clearly distinguished because the reflections are different, and when reading the image of the original, , since the back of the original is switched to white, the black portions shown in FIGS. 3 to 6 no longer appear on the copy. Furthermore, unlike conventional black border erasing, the area to be actually copied is not narrowed down, so it is possible to completely copy images, even at the edges of the document.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an embodiment of a copying machine to which the present invention is applied, FIG. 2 is a perspective view of the same, and FIGS. . 1 is a document, 26 is a transparent document pressure plate, 28 is a switching belt, 2
8a is a black background part, 28b is a white background part, and 35 is a motor.

Claims (1)

[Claims] (1) The document pressure plate that contacts the document is made of a transparent body, and a movable member having a low reflection portion and a high reflection portion is provided on the back side of the document pressure plate, and the low reflection portion of the movable member overlaps the document. When the size of the document is recognized by detecting the difference between the reflection of the base portion of the document and the reflection of the low reflection portion, and when the high reflection portion of the movable member overlaps the document, a copying operation is performed. A copying machine characterized by: