KR20060105147A - Image forming apparatus including a means for the image sensor guide escaping - Google Patents

Abstract

An image forming apparatus having a reading guide guiding means is disclosed. The image forming apparatus according to the present invention includes a reading unit when a reading unit passes through each end of a first flat glass contacting a document conveyed by an automatic document feeder and a second flat glass contacting a stationary document. And an escape means for separating the reading guide from the first or second flat glass end, thereby eliminating the possibility of image quality deterioration and the need to replace the transparent sheet due to the interposition of the transparent sheet. There is no fear of wear or damage due to the transport shock, there is an effect that the image quality deterioration due to the wear of the reading guide.

Reading guide, escape means, image forming apparatus

Description

Image forming apparatus including a means for the image sensor guide escaping}

1 is a side cross-sectional view schematically showing a feed path of an original by an ADF (auto document feeder) in a conventional image forming apparatus.

2 is a perspective view of an image forming apparatus according to the present invention;

Figure 3 is a perspective view of the main part of the reading guide escape means according to the invention.

4 to 6 are side cross-sectional views sequentially showing the action of the reading guide escape means in accordance with the present invention.

<Description of the symbols for the main parts of the drawings>

210.Auto document feeder (ADF)

220 Feeder 230 Feeder

240 ... Display panel 250 ... First flat glass

251 ... 2nd Flatbed Glass 270 ...

290 ... Reading 300 ... Reading Guide

310 ... reading guide end 320 ... reading guide face

330 Extrude Cam Rail 350 Extrude Cam

The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus having a reading unit for scanning an image recorded on an original.

Background Art [0002] Image forming apparatuses, such as printers, scanners, copiers, facsimiles, and the like, which print text or pictures on a recording medium, have recently been used in the form of a multifunction machine that performs various functions in combination. Among them, the scanner includes a reading unit that reads an image recorded on an original as an optical signal and converts it into an electrical signal.

In general, the reading unit reads an image on one axis of the original, and in order to read the original on two axes, the reading unit needs to be moved or the original needs to be moved. The scanner to which the readings are moved is usually called a flat bed type scanner. A distinct concept is a sheet feed type scanner in which a document is moved. Some scanners are equipped with an automatic document feeder (ADF) in a flatbed scanner and serve as a sheet-feed type.

Fig. 1 shows a sheet-feed combined image forming apparatus having a flatbed scanner as an automatic sheet feeding apparatus as a conventional image forming apparatus. Referring to this, there is provided a single piece of flat plate glass 50, 51, which includes an ADF section 50 at which a document supplied from the automatic document feeder 10 contacts and a reference 51 at which a stationary document is placed in a sheet. It can be partitioned into still documents. The document loaded in the tray 20 is brought into contact with the ADF section flat glass by the automatic feeding device 10, and the leading end of the document is discharged to the discharge tray 30 by the document guide 70. . A reading part guide 80 is interposed between the reading part 90 and the back surface of the flat glass 50, 51 to guide the movement of the reading part 90 and guide the reading part 90 and the flat glass 50, 51. Keep a constant gap between them. If a contact image sensor (CIS) is used in the reading unit 90, the depth of focus should be low and the gap should be reduced. The document to be discharged to the discharge bin 30 may be jammed by the front end portion is caught in the engaging portion of the plate glass and the document guide 70. In order to prevent jams and to consider the low depth of focus of the contact image sensor, the feed path of the document is positioned between the transparent sheet 70 and the automatic sheet feeder 10 through a thin transparent sheet 75 for passing light. Let's do it. However, due to the interposition of the transparent sheet 75 having a thickness tolerance, the depth of focus of the CIS sensor does not match, or the original passes through the transparent sheet 75, causing scratches on the transparent sheet 75, thereby degrading the image quality read. Or, there is a problem that the frequent replacement of the transparent sheet 75 is required.

On the other hand, although not shown in Figure 1, when the ADF plate glass and the stationary platen glass plate is separated separately, insert the document guide between each end of the separated plate glass without interposing the transparent sheet to jam the document (jam) Although it can be prevented, the reading part and the reading part guide pass through each end of the separated flat glass, and there is a risk of being easily worn or broken by a transfer shock. If the reading guide wears out and its dimensions change, the quality of the read image is degraded.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides an image forming apparatus that allows a reading portion and a reading guide to pass between the separated ends of the ADF flat plate glass and the stationary high flat plate glass without abrasion or transfer shock. There is a purpose.

The image forming apparatus of the present invention for achieving the above object,

A first flat glass contacting the document conveyed by the automatic document feeder, and a second flat glass contacting the stationary document; A reading unit slidably installed on the rear surface of the first or second flat glass and reading an image recorded in the document; A reading guide coupled to the reading section to maintain a gap between the reading section with respect to the first or second flat glass back surface; Escaping means for separating said reading portion and said reading portion guide from said first or second flat glass end when said sliding reading portion passes through an end of said first or second flat glass; It includes.

The escaping means includes a protruding cam provided between the end portions of the first and second flat glass; and a protruding cam rail provided in the read attachment guide so as to contact the protruding cam. The reading portion and the reading portion guide are escaped by the contact of the cam rail.

Preferably, the contact surface of the protruding cam and the protruding cam rail has a cycloid shape.

In addition, a document guide member for guiding the document leading end conveyed by the automatic sheet feeder as a discharge bin is provided between the end portions of the first and second flat glass plates, and the document guide member is jammed at the tip end of the transferred document. It is preferable to engage with the end of the first flat glass in a position to prevent a).

Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a perspective view showing the main part of the image forming apparatus according to the present invention. Referring to this, the image forming apparatus includes a first flat glass 250 in which an original conveyed by the automatic document feeder 210 (ADF) is in contact with a second flat glass 251 in contact with a stationary document. The first flat glass 250 and the second flat glass 251 are separated from each other. The display panel 240 displays the operation and status of the image forming apparatus and includes various operation keys. The document loaded on the tray 220 is transferred to the first flat glass 250 by the automatic sheet feeder 210. The reading unit 290 stationary on the rear surface of the first flat glass 250 reads the image recorded on the document. The read original is discharged to the discharge stage 230. An original guide member 270 having an inclined surface is provided between the ends of the first and second flat glass 251. The document guide member 270 guides the tip of the document passing through the first flat glass 250 to the discharge table 230. Originals supplied in sheets without the automatic sheet feeder 210 (ADF) are placed on the upper surface of the second flat glass 251. The reading unit 290 is transferred in the scanning direction from the rear surface of the second flat glass 251 to read the image of the stopped original. The initial position of the reading part 290 is the back surface of the 1st flat glass 250 at the time of reading the original supplied to an automatic document feeder, and the back surface of the 2nd flat glass 251 at the time of reading the stopped original.

The image sensor included in the reading unit 290 may be a contact image sensor (CIS) or a charge coupled device (CIS) that converts an optical signal obtained by scanning a document into an electrical signal. The depth of focus of the rod lens array employed in the CIS drops. Therefore, in the case of using the CIS, a good image quality may be obtained by closely attaching the CIS module to the rear surfaces of the first and second flat glass plates 250 and 251. A charge coupled device (CCD) having a relatively large depth of focus may be used as an image sensor.

A reading unit guide 300 is provided at both ends of the side of the reading unit 290, which is indicated by reference numeral A. This guides the transfer of the reading unit 290, and allows the reading unit 290 to maintain a constant gap with respect to the rear surfaces of the first and second flat glass plates 250 and 251.

3 is a perspective view of the reading guide 300 according to the present invention. Although not shown, the reading guide surface 320 is in contact with the rear surfaces of the first and second flat glass plates 250 and 251. The reading guide surface 320 guides the transfer of the reading 290 and maintains a constant gap. An embodiment in which the first and second flat glass plates 250 and 251 are coupled to a separate supporting member (not shown) and the reading portion guide surface 320 is brought into contact with the guide surface formed on the supporting member is not limited thereto. .

The reading guide end 310 helps convey the reading 290. The protruding cam rail 330 is provided separately from the reading guide surface 320. The protruding cam rail 330 pushes the reading unit guide 300 downward by contact with the protruding cam 350. As a result, the reading unit 290 and the reading unit guide 300 are evacuated a predetermined distance from the ends of the first and second flat glass plates 250 and 251. The reading part 290 and the reading part guide 300 escaped from the end portions of the first and second flat glass plates 250 and 251 are prevented from being transported or worn.

The protruding cam 350 is installed between the ends of the first and second flat glass glasses 250 and 251. The protruding cam 350 is preferably provided on an upper cover (not shown) of the image forming apparatus to which the first and second flat glass glasses 250 and 251 are fixed. The protruding cam 350 fixed to the upper cover is in contact with the protruding cam rail 330 to be moved.

It is preferable that the shape of the contact surface is a cycloid curve. This curve smoothes the fluctuation of the impact force upon contact of the protruding cam 350 and the protruding cam rail 330 and reduces the contact noise. The present invention is not limited thereto, and various embodiments may be used to escape the reading unit 290 and the reading unit guide 300 passing through end portions of the first and second flat glass plates 250 and 251.

4 to 6 sequentially illustrate the action of the escape means according to the invention. Referring to this, the reading guide 300 is in contact with the back of the first, second flat glass (250, 251) and guides the transfer of the reading (290). 4 to 6 illustrate an operation in which the reading unit 290 is transferred from the second flat glass 251 to the first flat glass 250. The operation of transferring the reading unit 290 from the first flat glass 250 to the second flat glass 251 is in reverse order. One pair of reading unit guides 300 are provided at each of both ends of the reading unit 290. Each reading guide end 310 induces contact between the first and second flat panes 250, 251 and the reading guide surface 320 to be initiated.

In FIG. 4, the distal end portion of the protruding cam 350 starts to press the protruding cam rail 330. The reading guide surface 320 begins to come into contact with the back surface of the second flat glass 251. In FIG. 5, the most end of the protruding cam 350 presses the protruding cam rail 330. The reading part 290 is transferred to the rear surface of the first flat glass 250 while the reading part guide surface 320 and the ends of the first and second flat glass plates 250 and 251 are in contact with each other. In FIG. 6, the distal end of the protruding cam 350 is separated from the protruding cam rail 330. The reading guide surface 320 is in contact with the rear surface of the first flat glass 250, and the document supplied by the automatic sheet feeder 210 is scanned. When the reading unit 290 passes through the ends of the first and second flat glass plates 250 and 251, the reading unit 290 and the reading unit guide 300 may include the protruding cam 350 and the protruding cam rail 330. ) Is escaped a predetermined distance from the ends of the first and second flat glass (250,251).

The height of the point where the document guide member 270 and the end of the first flat glass 250 are coupled is equal to or lower than the height of the upper surface of the first flat glass 250. This prevents the occurrence of jams in the mating surface of the document guide member 270 and the first flat glass 250.

On the other hand, the reading guide surface 320 is not in direct contact with the rear surfaces of the first and second flat glasses 250 and 251, and on a separate supporting member for fixing the first and second flat glasses 250 and 251. Even in the contacting embodiment, the embodiment of the same concept as described above is possible for the purpose of escaping the reading portion 290 and the reading portion guide 300 from the ends of the first and second flat glass 250, 251.

As described above, in the image forming apparatus having the reading guide guiding means according to the present invention, since the first and second flat glass are separately installed, there is a possibility of deterioration of image quality due to the interposition of the transparent sheet and the need for replacing the transparent sheet. This is eliminated and there is no fear that the reading and the reading guide will pass through each end of the separated first and second flat glass and be worn or broken by a transfer shock. In addition, image quality deterioration due to wear of the reading unit guide is also prevented.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and those skilled in the art to which the art belongs can make various modifications and other equivalent embodiments therefrom. Will understand. Therefore, the true technical protection scope of the present invention will be defined by the claims below.

Claims (5)

A first flat glass in contact with the document conveyed by the automatic sheet feeder, and a second flat glass in contact with the stationary document; A reading unit slidably installed on the rear surface of the first or second flat glass and reading an image recorded in the document; A reading guide for guiding the reading of the reading and maintaining a gap of the reading with respect to the rear surface of the first or second flat glass; Escaping means for separating the reading portion and the reading guide from the first or second flat glass end when the reading portion passes through an end of the first or second flat glass; Image forming apparatus comprising a. The method of claim 1, The escape means, A protruding cam provided between ends of the first and second flat glass; A protruding cam rail which is in contact with the protruding cam and provided in the reading portion guide; And the reading part and the reading part guide are evacuated by the contact between the protruding cam and the protruding cam rail. The method of claim 2, And a contact surface of the protruding cam and the protruding cam rail has a cycloid shape. The method of claim 2, The reading unit may include a contact image sensor (CIS) or a charge coupled device (CIS) which converts an optical signal obtained by scanning the document into an electrical signal. The method according to any one of claims 1 to 4, And a document guide member for guiding the document leading end conveyed by the automatic sheet feeder as a discharge bin between the first and second flat glass ends.

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