JPH0646219A - Picture information reader - Google Patents

Abstract

PURPOSE:To provide the picture information reader with simpler configuration whose size is not made larger even when the reader is provided with an automatic original feeder. CONSTITUTION:The reader consists of a usual read section 1 using a linear image sensor so as to read picture information of an original placed on a contact glass through main and sub scanning, a press plate section 2 provided with a pressing plate sheet 7 to retain the mount original, and an automatic original feeder 3 integrated with the pressing plate section 2, and with a means having a common picture information read position and moving the pressing plate sheet 7 so as to open a read area only in the operation of the automatic original feeder 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to image information of an original by using a one-dimensional image sensor such as a CCD (hereinafter referred to as a solid-state image sensor), which is applied to an image forming apparatus such as a copying machine or a facsimile. The present invention relates to an image information reading device that performs main scanning and sub scanning to read the information.

[0002]

2. Description of the Related Art As shown in FIG. 6, in a conventional image information reading apparatus, a slide member 50 on which a one-dimensional image sensor 51 is mounted is fixed to a wire 54 stretched between pulleys 52 and 53. Then, the drive motor 55 moves along the contact glass 59. The one-dimensional image sensor 51 reads image information by performing main scanning and sub-scanning on a document surface placed on the contact glass 59 while being pressed against the contact glass 59 by elastic means (hereinafter, referred to as normal mode).

A guide member 64 and three pairs of document feed roller pairs 6 for feeding the document from arrows 67 to 68.
An automatic document feeder (hereinafter, referred to as ADF) 62 composed of 5 and 66 and also serving as a pressure plate for glass is arranged in one region on the contact glass 59, and the pressing member 63 is not shown on the contact glass 59. It is for pressing the document on the glass surface. The contact glass 59 is further adhered with an original placement reference plate 74 which is white-painted on the back surface thereof and also serves as a white reference plate for correcting the light amount.

When the ADF 62 is used, the one-dimensional image sensor 51 reads at the position indicated by reference numeral 69. When the leading edge of the original inserted from the direction of arrow 67 reaches the reading position 69, the one-dimensional image sensor 51 starts reading the original, and after the reading is completed, the original is indicated by arrow 6.
It is discharged in the direction shown in 8 (hereinafter referred to as ADF mode).

[0005]

In the image information reading apparatus provided with the ADF, as shown in FIG. 7, the reading position in the normal mode is located slightly inside from the edge of the fixed pressure plate sheet 7. While existing from the area, AD
The reading position in the F mode is located outside the reading area in the normal mode. In such a configuration, A
Considering that normal reading is performed from the reading position in the DF mode, the area between the original reading position in the normal mode and the reading position in the ADF mode (portion A in FIG. 7) is recognized as black, If an original smaller than the recording paper size is copied, a black band may be recorded in an area exceeding the original size. This is because the pressure plate sheet 7 indicating the reading reference in the normal mode is fixed and the sheet cannot be extended to the reading position in the ADF mode.

However, even in the image information reading apparatus provided with such an ADF, there is a demand for downsizing of the apparatus. For this reason, for example, in JP-A-1-311762, the pressure plate portion and the ADF can be slid. And then ADF
It has been proposed to provide the image information reading position in the mode within the image information reading scanning range in the normal mode.

The present invention is different from the method proposed in Japanese Patent Application Laid-Open No. 1-311762, in which it is unavoidable to provide a moving means which is not simple and small in size for making both the pressure plate portion and the ADF slidable. In order to meet the above-mentioned demand, it is an object to provide an image information reading device which has an ADF and has a simpler configuration and which suppresses an increase in size of the device.

[0008]

The present invention solves this problem by
A normal reading unit that reads image information of an original document placed on the contact glass by main scanning and sub-scanning with a one-dimensional image sensor, a pressure plate unit that is provided with a pressure plate sheet and presses the placed original document, and is integrally configured with the pressure plate unit. Image having a common image information reading position and having means for moving the pressure plate sheet so as to open the reading area only when the automatic document feeder is operated. The information reading device solves the problem.

It is preferable that the moving means of the pressure plate sheet comprises an elastic member, a winding means for winding the pressure plate sheet against the elastic force, and a driving means for driving the winding means. is there.

A moving member for moving the pressure plate sheet is slidably attached to the pressure plate frame of the pressure plate portion,
It is also suitable if it is composed of a drive means for moving the moving member.

It is also advantageous if the pressure plate sheets are divided and one pressure plate sheet piece moves relative to the other pressure plate sheet piece so as to open and close the reading area.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments based on the drawings.

FIG. 1 shows an overall outline of an image information reading apparatus according to the present invention.

Reflecting means 8 which moves along the contact glass 6 in order to perform main scanning and sub-scanning on image information of an original document (not shown) such as a book placed on the contact glass 6, and A plurality of reflecting means 10 and 11 for providing an optical path for transmitting the image information illuminated on the lens to the CCD 9 through the lens 5 are arranged inside the main body of the apparatus to constitute the normal reading section 1. The pressure plate 2 above the normal reading unit 1 is provided with a white pressure plate sheet 7 that can move along the contact glass 6 so as to hold a placed document (not shown). An image information reading apparatus is configured by including an ADF 3 that is integrally configured with the pressure plate unit 2 and that separates a plurality of sheet originals (not shown) stacked on the pressure plate unit 2 by a plurality of roller pairs and conveys them in the arrow direction. To be done.

FIG. 2 shows in detail the common image information reading position area in the normal mode in which the normal reading section 1 is operated and in the ADF mode in which the ADF 3 is operated. In the normal mode in which the ADF 3 is not used, the edge portion of the pressure plate sheet 7 extends to the point A that covers the common image information reading position 15. On the other hand, in the ADF mode in which the ADF 3 is used, the edge portion of the pressure plate sheet 7 moves to point B so that the image information of the sheet document conveyed through the roller group of the ADF 3 can be read. Open the reading area.

The movement of the pressure plate sheet 7 is performed by determining whether or not the document is in the ADF and the ADF is in an operating state by a known detecting means.

FIG. 3 shows one construction for moving the pressure plate sheet 7.

Springs 16 are arranged and fixed at both corners of the pressure plate sheet 7 at the common image information reading position side. A take-up shaft 17 for taking up the pressure plate sheet 7 is arranged on the side opposite to the image information reading position, and is connected to a driving means 18 including a motor. When the drive means 18 operates in response to a signal from the ADF operation detecting means, the pressure plate sheet 7
The spring 16 is moved against the elastic force by the amount necessary to open the reading area. When the ADF does not work,
The drive means 18 reversely rotates and moves the pressure plate sheet 7 until the spring 16 returns to the return state. By these movements, the edge portion of the pressure plate sheet 7 moves between AB in FIG.

Of course, the driving means 18 may be a solenoid or the like.

FIG. 4 shows another structure for moving the pressure plate sheet 7.

The flat pressure plate sheet 7 includes a cushion material 19
It is fixed to a moving body 20 which is slidably attached to a pressure plate frame (not shown) sandwiching the. When the moving body 20 is moved by the moving means 21 such as a solenoid, the edge portion of the pressure plate sheet 7 moves between AB in FIG.

FIG. 5 schematically shows a structure in which only a part of the pressure plate sheet moves.

The pressure plate sheet 7 is divided into two parts, and a stationary pressure plate sheet piece 7a that does not move is provided with a sliding pressure plate sheet piece 7b that moves like a shutter. The movement opens and closes the reading area.

It suffices if this opening / closing is performed by a known method including the driving / moving means according to FIGS. 3 and 4 described above.

[0025]

According to the image information reading apparatus of the first aspect, the normal reading section for reading the image information of the original document placed on the contact glass by the main scanning and the sub scanning by the one-dimensional image sensor, and the pressure plate sheet. It is composed of a pressure plate that holds the placed document and an automatic document feeder that is integrated with the platen, has a common image information reading position, and opens the reading area only when the automatic document feeder operates. As described above, since the means for moving the pressure plate sheet is provided, it is possible to suppress an increase in size of the device with a simpler configuration.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an image information reading device according to the present invention.

FIG. 2 is a detailed view of the vicinity of the reading position in the apparatus of FIG.

FIG. 3 is a schematic perspective view showing an embodiment of the moving means of the pressure plate sheet according to the present invention.

FIG. 4 is a schematic end view showing another embodiment of the moving means of the pressure plate sheet according to the present invention.

FIG. 5 is a schematic perspective view showing an embodiment of the moving means of the pressure plate sheet according to the present invention.

FIG. 6 is a schematic configuration diagram of a known image information reading device.

7 is a detailed view of the vicinity of the reading position in the apparatus of FIG.

[Explanation of symbols]

 1 Normal reading unit 2 Pressure plate unit 3 Automatic document feeder 6 Contact glass 7 Pressure plate sheet

Claims (4)

[Claims] 1. A normal reading unit for reading image information of a document placed on a contact glass by a main scanning and a sub-scanning by a one-dimensional image sensor, a pressure plate unit provided with a pressure plate sheet for pressing the placed document, and And a means for moving the pressure plate sheet so as to open the reading area only when the automatic document feeder is in operation, which has a common image information reading position. An image information reading device provided. 2. The pressure plate sheet moving means comprises an elastic member, a winding means for winding the pressure plate sheet against the elastic force, and a driving means for driving the winding means. The image information reading device according to claim 1. 3. The moving means for moving the pressure plate sheet comprises a moving member slidably attached to the pressure plate frame of the pressure plate portion, and a driving means for moving the moving member. Item 1. The image information reading device according to item 1. 4. The image information according to claim 1, wherein the pressure plate sheet is divided, and one pressure plate sheet piece moves with respect to the other pressure plate sheet piece so as to open and close the reading area. Reader.