JP2659141B2 - Document cassette - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document cassette used for loading a document carrying image information into an image reading apparatus.

[Prior art] In the fields of printing, plate making, etc., streamlining of work processes,
2. Description of the Related Art For the purpose of improving image quality and the like, an image scanning / reading / reproducing system which electrically processes image information carried on a document and creates a film original has been adopted.

In an image reading apparatus constituting this image scanning reading and reproducing system, for example, a document such as a developed film is main-scanned by a light beam while being conveyed in a sub-scanning direction via a document cassette. The held image information is read two-dimensionally.

In this case, the document cassette has a set of support members at least one of which is formed of a transparent material, and light reflected or transmitted from the document via the transparent support member is provided in the reading unit. Image information is read by being photoelectrically converted by an optical / electrical conversion element such as a CCD.

[Problems to be Solved by the Invention] In this document cassette, since the document is directly positioned and placed on the support member, depending on the state of the document, when the read image information is reproduced, ,
The reproduced image may be uneven. That is,
This is because, when the original and the support plate do not closely adhere to each other and there is a gap between them on the order of the wavelength of the reading light, unevenness due to the Newton ring occurs due to the interference of the reading light.

The present invention has been made in view of this type of problem,
An object of the present invention is to provide a document cassette that can effectively prevent the occurrence of Newton rings and can easily cope with various documents having different sizes.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides two transparent support members for holding a sheet-shaped document, and the document mounted on each of the two support members, A spacer member for supporting and supporting the document at a distance from the support member; and a document placement opening of the spacer member for changing the size of the document placement opening of the spacer member according to the size of the document. An adjusting member that can be attached to an end of the adjusting member, wherein the spacer member and the adjusting member have the same thickness, and the end of the document placement opening and the adjusting member are A locking groove and a locking piece are provided for positioning and holding.

[Operation] In the document cassette configured as described above, when the sheet-shaped document is held by the support member via the spacer member, the distance between the document and the support member is sufficiently longer than the wavelength of the reading light. A large gap is provided. Therefore, when the image information is read by being transported to the reading unit of the document cassette image reading apparatus, the light related to the image information directly obtained from the document and the light related to the image information once reflected by the support member may interfere with each other. Absent. Further, when the sizes of the originals are different, an adjusting member is attached to the spacer member, and the original arrangement opening of the spacer member is changed corresponding to the original. On the other hand, the same spacer member can be used.

Embodiment An embodiment of the document cassette according to the present invention will be described below in detail with reference to the accompanying drawings.

1 to 3, reference numeral 10 indicates a document cassette according to the present embodiment. The original cassette 10 includes a substantially rectangular frame 12, a support glass plate (support member) 14 mounted at the center of the frame 12, and a cover glass plate (support Member) 16, spacer members 20 and 22 respectively fixed to the support glass 14 and the cover glass plate 16, and document placement openings 24 and 26 of the spacer members 20 and 22 according to the size of the document S. In order to change the size, there are provided adjusting members 28 and 30 which can be attached to the spacer members 20 and 22.

The document cassette 10 is loaded in an image reading device described later and transported in the direction of the arrow X. V-shaped grooves 34a and 34b extending on the both sides of the frame 12 along the direction of the arrow X are provided.
Is formed. At the front of the frame body 12 in the direction of the arrow X, a document cassette 10 and a cassette identification unit 36 for identifying the document S held in the document cassette 10 are provided. The cassette identification unit 36 is composed of the document cassette 10 and a light transmitting unit having a predetermined pattern corresponding to the type of the document S. At the rear of the frame 12 in the direction of the arrow X, a cover glass plate
A stopper member 38 for locking the 16 to the frame 12 is provided.

As shown in FIGS. 2 and 3, the spacer member 20,
A pair of openings 24 and 26 provided in the
And each opening 2
A pair of bent grooves 40 and 42 for positioning the adjusting members 28 and 30 communicate with the ends of the four and 26, respectively. The spacer member 20 is provided with positioning convex portions 44a to 44c so as to sandwich the pair of openings 24.

The spacer members 20, 22 are supported by the supporting glass plate 14 with an adhesive or the like.
And a cover glass plate 16. The thickness of the spacer members 20, 22 is set to, for example, 0.1 mm or more so as to be sufficiently larger than the wavelength of the reading light. As the spacer members 20 and 22, a stainless steel plate or a film can be used.

The adjusting members 28 and 30 have the same thickness as the spacer members 20 and 22. The length H is selected according to the size of the document S, and the locking of the openings 24 and 26 is performed. Locking pieces 46, 48 are provided in the grooves 40, 42.

FIG. 4 shows a schematic configuration of an image reading device 50 for reading an image of a document S set in the document cassette 10 configured as described above, preferably, a film that has been developed.

The image reading device 50 has a cassette attachment / detachment portion 52 at one upper end side, and a cassette insertion port near the cassette attachment / detachment portion 52.
The document cassette 10 and an identification mechanism 56 for identifying the type of the document S held in the document cassette 10 are provided near the cassette insertion opening 54. Identification mechanism
Reference numeral 56 denotes a light-emitting unit 58 and a light-receiving unit 60 that face the document cassette 10 to be conveyed therebetween.

One end of the transport mechanism 62 is provided near the identification mechanism 56, and the other end of the transport mechanism 62 extends above a rotary table described later. The transport mechanism 62 includes a transport roller 66 that contacts the upper surface of the frame 12 of the document cassette 10 and a plurality of guide rollers 64 that are disposed along the transport direction. V provided on both sides
It engages with the U-shaped grooves 34a, 34b.

Below the transport mechanism 62, a document table 68 is disposed via a sub-scanning mechanism 70 so as to be able to advance and retreat in the sub-scanning direction (the direction of arrow X). The sub-scanning mechanism 70 includes a rotary drive source 72, and a document table 68 is displaced in the direction of arrow X by a ball screw 74 connected to the rotary drive source 72.

The document table 68 is provided with a trimming mechanism 76 for moving the document cassette 10 forward and backward in a trimming direction, that is, a direction orthogonal to the sub-scanning direction (the direction of arrow X). The trimming mechanism 76 includes a trim base 80 that is displaced by a rotary drive source 78 attached to a document table 68, and a trim base 80.
80 has an opening 82 in which the document cassette 10 is positioned. The document table 68 has a rotation mechanism 84 for rotating the document cassette 10 through a rotation table 86 by a predetermined angle.

On the other end side of the transport mechanism 62, a light source 88 constituting a transmission illumination mechanism is provided extending in a main scanning direction substantially orthogonal to the arrow X direction. An image reading unit 90 that photoelectrically reads the illumination light L is provided. The image reading unit 90 includes an imaging lens 92 that can move forward and backward in the optical axis direction, and the imaging lens
A photoelectric conversion unit 96 that can move forward and backward with respect to 92 is provided. The photoelectric conversion unit 96 is, for example, a CCD, and photoelectrically reads image information recorded on the document S.

The document cassette 10 and the image reading apparatus 50 in which the document cassette 10 is loaded according to the present embodiment are configured as described above. Next, the operation thereof will be described.

First, in the state shown in FIG. 1, a document S and an adjusting member 28 corresponding to the size of the document S are fixed to the opening 24 of the spacer member 20 on the supporting glass plate 14. That is, the locking piece 46 of the desired adjusting member 28 is arranged corresponding to the locking groove 40 of the spacer member 20, and the document S is positioned and arranged in the opening formed by the adjusting member 28 and the opening 24. You.

In this case, the document S may be merely placed on the opening 24, but is preferably fixed to the spacer member 20 and the adjusting member 28 using an adhesive tape 98 as shown in FIG. It is desirable to keep. This is because the positioning of the document S is ensured, and slack of the document S can be eliminated. At that time, after fixing the document S on the spacer member 20,
The spacer member 20 may be positioned on the supporting glass plate 14.

After the document S is positioned on the spacer member 20 in this manner, the cover glass plate 16 is swung, and the document S is pressed via the spacer member 22 fixed thereto. The plate 16 is locked. Here, the original S is made up of the spacer members 20 and 22 and the adjustment member 28,
As a result, the document holder 10 is held in the document cassette 10 without being loosened. Also, a predetermined gap is provided between the document S and the supporting glass plate 14 and the cover glass plate 16.

Next, the document cassette 10 containing the desired document S is
From the cassette loading / unloading section 52 of the image reading device 50 to the cassette insertion port
Inserted into 54. The identification mechanism 56 provided in the vicinity of the cassette insertion port 54
By reading the code set in 36, the document cassette 10 and the type of the document S stored in the document cassette 10 are identified. That is, the light emitted from the light emitting section 58 constituting the identification mechanism 56 passes through the predetermined light transmitting section of the cassette identifying section 36 and reaches the light receiving section 60, whereby the type of the original cassette 10 and the type of the original S are identified. Is done.

The document cassette 10 includes transport rollers that constitute the transport mechanism 62.
66 rolls on the upper surface of the frame 12, and guide rollers 64 are fitted into the V-shaped grooves 34a and 34b on both sides of the frame 12, and are conveyed to the rotary table 86. This turntable 86
The angle adjustment and trimming of the document S held in the document cassette 10 are performed as necessary.

After the document cassette 10 is positioned on the document table 68, the rotation drive source 72 constituting the sub-scanning mechanism 70 is driven, and the document table 68 is conveyed in the sub-scanning direction (the direction of arrow X) under the action of the ball screw 74. At the same time, the light source 88 is energized. The illumination light L derived from the light source 88 is transmitted through the document S in the main scanning direction, so that the image information carried on the document S is extracted as an optical signal, and the image information as the optical signal is converted into an optical axis. The light is guided to a photoelectric conversion unit 96 via a predetermined imaging lens 92 disposed above. The photoelectric conversion unit 96 photoelectrically reads the image information as the optical signal. During this time, the platen 68
Are conveyed in the sub-scanning direction in the arrow X direction, the original S is two-dimensionally scanned by the illumination light L, and all the image information is read.

Here, the document S held in the document cassette 10 is
Since it is sandwiched between the spacer members 20 and 22 and the adjustment members 28 and 30, it is separated from the support glass plate 14 and the cover glass plate 16 by a distance sufficiently larger than the wavelength of the illumination light L. Therefore, even when a part of the illumination light L is reflected between the document S and the supporting glass plate 14 or the cover glass plate 16 and enters the photoelectric conversion unit 96, this light is directly transmitted from the document S to the photoelectric conversion unit 96. The light does not interfere with the light incident on the conversion unit 96. As a result, no interference fringes are formed on the photoelectric conversion unit 96, and an even image can be obtained when the image information is reproduced.

Further, when the sizes of the originals S placed in the original cassette 10 are different, the length H of the adjusting members 28 and 30 is simply selected in accordance with the new original S, and the same spacer member is used.
20, 22 can be used. Accordingly, when various originals S having different sizes are used, it is not necessary to prepare a large number of spacer members 20 and 22 corresponding to the originals S, and the effect of being economical can be obtained.

By the way, the original S which is considerably smaller than the original S described above.
Is used, the adjusting members 100 and 102 shown in FIG. 5 may be employed.

That is, the adjusting members 100 and 102 have openings 104a, 104b and 10 formed slightly smaller than the original S.
6a and 106b, and the adjusting member 100 has positioning convex portions 108a and 108b between the openings 104a and 104b.
Is provided.

Therefore, after the document S is positioned and fixed in the openings 104a and 104b of the adjustment member 100 via the convex portions 108a and 108b, the adjustment member 100 is disposed in the opening 24 of the spacer member 20,
As a result, the document S having a small size is accurately placed on the document cassette 10.

[Effects of the Invention] As described above, the following effects are obtained in the document cassette according to the present invention.

When the sheet-shaped document is held by the support member via the spacer member, a gap is provided between the document and the support member, which is sufficiently larger than the wavelength of the reading light. When the image information is read by being conveyed to the reading unit, the light related to the image information directly obtained from the document does not interfere with the light related to the image information once reflected by the support member. As a result, the so-called Newton ring does not occur in the document cassette, and the image information can be read extremely well without unevenness.

Further, when the sizes of the originals are different, an adjusting member is attached to the spacer member, and the original arrangement opening of the spacer member is changed corresponding to the original. On the other hand, the same spacer member can be used, which is efficient.

[Brief description of the drawings]

FIG. 1 is a perspective view of the configuration of a document cassette according to the present invention, FIG. 2 is a plan view of the document cassette, FIG. 3 is a cross-sectional view of the document cassette, and FIG. FIG. 5 is a front view of an adjusting member according to another embodiment. 10 Document cassette 12 Frame 14 Support glass plate 16 Cover glass plate 20, 22 Spacer member 28, 30 Adjusting member 40, 42 Lock groove 46, 48 Stop piece 50: Image reading device 52: Cassette attaching / detaching section 62: Transport mechanism 70: Sub-scanning mechanism 88: Light source 90: Image reading section 100, 102: Adjusting members 104a, 104b: Opening 106a , 106b: Opening S: Original

Claims (1)

(57) [Claims] A transparent support member for holding a sheet-shaped document; a spacer member mounted on each of the two support members for supporting the document separately from the support member; An adjusting member that can be attached to an end portion of the document placement opening of the spacer member so as to change the size of the document placement opening of the spacer member according to the size of the spacer member. The member and the adjusting member have the same thickness, and the end side of the document placement opening and the adjusting member are
A document cassette comprising a locking groove and a locking piece for positioning and holding each other.