JP4124042B2 - Image reading device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image reading apparatus.
[0002]
[Prior art]
There is known an image reading apparatus including a document holder for supporting a document such as a photographic film, a housing having an opening, and a reading unit that scans and reads the document supported by the document holder inserted from the opening. ing. The document holder is inserted through the opening, and the image reading apparatus scans the document while scanning the document holder inserted in the horizontal direction. When the reading is completed and the user gives an instruction to eject the document holder, the image reading apparatus conveys the document holder in the direction opposite to that at the time of reading and ejects it from the opening.
[0003]
[Problems to be solved by the invention]
However, according to the conventional image reading apparatus, there is a problem that when the document holder is discharged from the opening, the document holder falls off due to its own weight. When the document holder is discharged in the horizontal direction, the discharged portion loses the lower support. For this reason, the document holder falls off due to gravity when the center of gravity is discharged from the opening. If the document holder falls off, the document holder may be damaged by a drop impact, or the supporting document may be damaged.
[0004]
The present invention has been created in view of such a problem, and an object of the present invention is to provide an image reading apparatus that prevents a document holder from falling off when the document holder is discharged.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, an image reading apparatus according to the present invention is a document holder that supports a document , and includes a dent provided at an end on the rear side in the advancing direction when the document is discharged, A document holder having a projecting portion provided so as to project upward, a housing having an opening , and reading means for scanning a document supported in the housing by the document holder to create a digital image A pair of rollers for vertically holding the document holder, a discharge means for horizontally transporting the document holder and discharging it from the opening , and a track in which the document holder is transported in the housing A document reading device including a fulcrum portion located on the opening side of the roller pair, wherein the concave portion of the document holder is held by the roller pair. The document holder, which cannot be clamped by the roller pair, is tilted by its own weight with the support position by the fulcrum part as a fulcrum, and the protrusion is locked by the upper roller of the roller pair. It is characterized by that.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples.
FIG. 2 is a schematic diagram showing an image scanner 1 as an image reading apparatus according to an embodiment of the present invention. In FIG. 2, the A direction is the horizontal direction. The image scanner 1 creates a digital image by scanning the document M supported by the document holder 20 inserted through the opening 12 provided in the housing 11. In the present embodiment, description will be given by taking as an example a document holder 20 that supports a transparent document such as a photographic film.
[0011]
The optical system 13 (see FIG. 3) includes a light source 13a, a mirror 13b, and a lens 13c. The light source 13 a is composed of a tube illuminating device such as a xenon lamp, and is disposed in the housing 11 with a longitudinal axis extending parallel to the longitudinal axis of the linear image sensor 14. The mirror 13b and the lens 13c form an optical path T that causes the transmitted light on the main scanning line of the document irradiated by the light source 13a to form an image on the linear image sensor 14. In this embodiment, the document holder 20 that supports a transparent document will be described as an example. However, the document holder may support a reflective document. When a reflected document is read, a linear image sensor is used from the track of the document holder. What is necessary is just to provide the light source for reflection originals in 14 side.
[0012]
The linear image sensor 14 includes a plurality of pixels such as photodiodes arranged in a straight line in the direction perpendicular to the paper surface (main scanning direction) in FIG. 2, and emits light in a predetermined wavelength region such as visible light, infrared light, and ultraviolet light. Charges obtained by photoelectric conversion are accumulated for a certain period of time, and an electrical signal correlated with the amount of light received for each pixel is output using a CCD (Charge Coupled Device), a MOS transistor switch, or the like.
[0013]
The sub-scanning drive unit 16 (see FIG. 3) includes a conveyance roller 16a, a driven roller 16b, a driven roller 16c, a driven roller 16d, a motor that rotates the conveyance roller 16a, a gear train, a drive circuit, and the like. Contained. The positions of the transport roller 16a and the driven roller 16c are fixed. On the other hand, the driven roller 16b and the driven roller 16d are not restricted in the vertical movement, and are pressed toward the document holder 20 by a pressing member such as a spring (not shown). As a result, the document holder 20 is positioned in the vertical direction. The “roller pair that vertically holds the document holder” described in the claims corresponds to the conveying roller 16a and the driven roller 16b. The sub-scanning drive unit 16 is provided in the vicinity of the opening 12 as illustrated. The sub-scanning drive unit 16 moves the main scanning line with respect to the document by conveying the document holder 20 in the b direction. In this embodiment, the case where the main scanning line is moved by conveying the document holder 20 will be described as an example. However, the main scanning line is moved by carrying the linear image sensor 14 mounted on a carriage. May be.
[0014]
Further, the sub-scanning drive unit 16 also functions as a discharge unit. When the user gives an instruction to eject the document holder 20, the sub-scanning drive unit 16 rotates the transport roller 16a in the reverse direction from that at the time of reading. As a result, the document holder 20 is conveyed in the horizontal direction and discharged from the opening 12.
The driven roller 16b, which is a part of the discharging means, is also used as a drop-off preventing means, and functions as a stopper that engages with the protruding portion 34 (see FIG. 1C). Details will be described later. When the driven roller 16b is used as a stopper, the configuration of the image scanner 1 can be simplified because it is not necessary to separately provide a stopper.
[0015]
As shown in the figure, the fulcrum portion 21 serving as a drop-off prevention means is provided below the track of the document holder 20 and closer to the opening 12 than the driven roller 16b serving as a stopper. In this embodiment, the fulcrum portion 21 is provided so as to contact the document holder 20 supported horizontally. However, when the document holder 20 is supported horizontally, the fulcrum portion 21 should not contact the document holder 20. May be. Further, a wall forming the lower inner wall surface of the opening 12 may be used as the fulcrum portion 21.
[0016]
FIG. 3 is a block diagram showing the image scanner 1.
The main scanning drive unit 15 is mounted on a substrate fixed to the image scanner 1. The main scanning drive unit 15 is a drive circuit that outputs drive pulses necessary for driving the linear image sensor 14 to the linear image sensor 14. The main scanning drive unit 15 includes, for example, a synchronization signal generator, a driving timing generator, and the like.
[0017]
The analog front end (AFE) unit 17 includes an analog signal processing unit, an A / D converter, and the like. The analog signal processing unit performs amplification, noise reduction processing, and the like on the electric signal output from the linear image sensor 14 and outputs the result. The A / D converter quantizes the electric signal output from the analog signal processing unit and outputs an output signal in a digital representation having a predetermined bit length.
[0018]
The digital image processing unit 18 performs processing such as shading correction, gamma correction, defective pixel interpolation by pixel interpolation, white balance correction, and image signal sharpening on the output signal output from the AFE unit 17. Create a digital image.
The control unit 19 includes a CPU 19a, a ROM 19b, and a RAM 19c. The CPU 19a executes computer programs stored in the ROM 19b to control each unit of the image scanner 1. The ROM 19b is a memory that stores various programs and data. These various programs and data may be downloaded and input from a predetermined server via a network, or may be read and input from a computer-readable storage medium such as a removable memory. The RAM 19c is a memory that temporarily stores programs and data.
[0019]
Next, the document holder 20 will be described.
FIG. 4 is a top view schematically showing the document holder 20. The document holder 20 includes a plurality of document windows 31, two recessed portions 32, a tapered surface 33, a protruding portion 34, a white reference window 35, a guide groove 36, and the like.
The guide groove 36 is a groove for guiding the document holder 20 in the sub-scanning direction. When the document holder 20 is conveyed by the sub-scanning drive unit 16, the main scanning line is perpendicular to the guide groove 36. The document holder 20 is inserted into the opening 12 (see FIG. 2) from the protruding portion 34 side shown in FIG. 4, guided by a guide provided in the housing 11, and conveyed in the sub-scanning direction.
[0020]
The white reference window 35 is a substantially rectangular opening whose long side extends in a direction perpendicular to the guide groove 36. The white reference window 35 is a window provided for setting white reference data for performing shading correction. The white reference data of each pixel is set by receiving the light passing through the white reference window 35 with the linear image sensor 14.
The document window 31 is a rectangular opening for storing a document such as a film. The document is positioned in the document window 31 by being held by a rectangular holding member (not shown) so that the range to be read is accommodated in the document window 31. That is, the document holder 20 supports the document via the holding member.
[0021]
The recess 32 is provided at the left and right corners of the end on the side where the white reference window 35 is formed. The dent portion 32 is a dent provided for the user to easily insert the leading end portion of the document holder 20 between the conveyance roller 16a and the driven roller 16b.
FIG. 5 is a schematic diagram for explaining the positional relationship between the recess 32 and the driven roller 16b. The cross section of the document holder 20 shown in FIG. 5 is a cross section taken along line II shown in FIG. As shown in the figure, the recess 32 is provided at a position corresponding to the driven roller 16b. As described above, since the document holder is held between the roller pair, if there is no recess 32, the user needs a large force when inserting the leading end of the document holder 20 between the roller pair. When the recess 32 is provided, a force for inserting the tip is small, and the insertion becomes easy.
[0022]
6 is a cross-sectional view showing a dent 32 portion of the cross section taken along the line II-II shown in FIG. The bottom wall surface 37 of the recess 32 is continuous with the surface 38 through the tapered surface 33. The tapered surface 33 is provided to make it easier for the driven roller 16b to ride on the surface 38 when the document holder 20 is conveyed. As shown in the figure, since a gap is formed between the driven roller 16b and the bottom wall surface 37 of the recess 32, when the user releases the hand in this state, the document holder 20 is tilted with the fulcrum 21 described above as a fulcrum. The bottom wall surface 37 of 32 abuts on the driven roller 16b.
[0023]
As shown in FIG. 6, the protruding portion 34 is provided so as to protrude from the end portion of the document holder 20 where the recessed portion 32 is provided. As shown in FIG. 4, the protruding portion 34 of the present embodiment protrudes in a wall shape. The document holder 20 is first inserted into the opening 12 and conveyed from the end on the side where the protruding portion 34 is provided, and when ejected, the original holder 20 is conveyed in the direction opposite to the direction of insertion from the opening 12. Discharged. Therefore, when the document holder 20 is discharged, the traveling direction is the c direction shown in FIG. Accordingly, the end provided with the protrusion 34 is on the rear side in the traveling direction when the document holder 20 is discharged. The document holder 20 is inserted through the opening 12 with the surface 38 facing upward. For this reason, the protruding portion 34 is provided so as to protrude upward when the document holder 20 is discharged. When the protrusion 34 is provided in the recess 32, the height of the document holder when being conveyed can be reduced. For example, when the protruding portion protrudes upward from the surface 38 in FIG. 6, the protruding portion abuts against the driven roller 16b when the document holder is inserted, which becomes a major obstacle. If the height of the document holder 20 when it is conveyed can be reduced, the insertion of the document holder 20 is facilitated, and the volume of the space through which the document holder 20 passes can be reduced in the housing 11. Can be small.
[0024]
Next, the operation of the image scanner 1 will be described.
First, an operation for reading a document will be described. The user inserts the document to be read into the opening 12 while being supported by the document holder 20. When the leading end of the document holder 20 is inserted between the transport roller 16a and the driven roller 16b, the control unit 19 detects that the document holder 20 has been inserted by a sensor (not shown) and controls the sub-scanning drive unit 16. Then, the conveyance roller 16a is rotated to convey the document holder 20. When the document holder 20 is transported to a predetermined reading position, the control unit 19 turns on the light source 13a and controls the sub-scanning driving unit 16 and the main scanning driving unit 15 to transport the document holder 20 on the main scanning line of the document. Scan. The image scanner 1 outputs an electrical signal corresponding to the amount of received light to the AFE unit 17, and the digital image processing unit 18 performs a predetermined process on the output signal output from the AFE unit 17 to create a digital image.
[0025]
Next, an operation for discharging the document holder 20 will be described.
FIG. 1 is a schematic diagram for explaining an operation of discharging the document holder 20. When the reading is completed, the user operates an operation unit (not shown) to instruct to discharge the document holder 20. When the discharge is instructed, the control unit 19 reversely rotates the conveyance roller 16a and conveys the document holder 20 in the C direction. FIG. 1A shows a state where the taper surface 33 is discharged until it is positioned immediately before the driven roller 16b. When the taper surface 33 passes through the driven roller 16b, the document holder 20 loses its upper support, so that its own weight causes the rear end portion to rise with the fulcrum portion 21 as a fulcrum as shown in FIG. The bottom wall surface 37 of this is in contact with the driven roller 16b. At this time, the center of gravity of the document holder 20 has lost its support, and the document holder 20 tends to slide out of the housing 11 at that angle, that is, to drop out. However, as shown in FIG. 1 (C), the projecting portion 34 comes into contact with the driven roller 16b and stops in that state when it slips slightly. That is, the protrusion 34 is locked to the driven roller 16b. As a result, the document holder 20 is prevented from falling off. In this embodiment, the driven roller 16b is used as a stopper. However, the driven roller 16b is not used as a stopper, and a stopper may be provided separately.
[0026]
According to the image scanner 1 according to the embodiment of the present invention described above, the document holder 20 is provided with the protruding portion 34, and when the document holder 20 is about to fall off, the protruding portion 34 is engaged with the driven roller. Stops and prevents falling out. Therefore, according to the image scanner 1, it is possible to prevent the document holder 20 from dropping off when the document holder 20 is discharged. As a result, it is possible to prevent the document holder from being damaged or the document from being scratched by the impact of dropping.
[0027]
Further, as shown in FIG. 1C, the document holder 20 stops in a state where most of the document holder 20 is ejected, so that the user only needs to take out the remaining few parts, and the effort for taking out can be reduced.
Further, since the locking can be released by lifting the end on the side discharged to the outside of the casing 11, the user can take out the entire document holder 20 from the casing 11 by lifting and pulling the end. Easy to take out.
[0028]
In this embodiment, the case where the protruding portion 34 protrudes upward when discharged is described as an example. However, the protruding portion 34 may protrude beyond the upper portion as long as it can engage with the stopper. For example, you may make it protrude in the direction which cross | intersects the advancing direction from the end surface parallel to a advancing direction.
[Brief description of the drawings]
FIGS. 1A, 1B, and 1C are schematic views showing a state in which a document holder according to an embodiment of the present invention is discharged.
FIG. 2 is a schematic diagram of an image reading apparatus according to an embodiment of the present invention.
FIG. 3 is a block diagram of an image reading apparatus according to an embodiment of the present invention.
FIG. 4 is a top view of a document holder according to an embodiment of the present invention.
FIG. 5 is a schematic diagram of a document holder and a roller according to an embodiment of the present invention.
FIG. 6 is a cross-sectional view of a document holder according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Image scanner (image reading apparatus), 11 housing | casing, 12 opening part, 13 optical system (reading means), 14 linear image sensor (reading means), 15 main scanning drive part (reading means), 16 subscanning drive part ( Reading means, discharging means), 16b driven roller (reading means, discharging means, drop-off prevention means), 17 analog front end part (reading means), 18 digital image processing part (reading means), 19 control part (reading means), 20 document holder, 21 fulcrum part (drop-off prevention means), 34 protrusion

Claims (1)

A document holder for supporting a document , the document holder having a recessed portion provided at an end portion on the rear side in the traveling direction when discharged, and a protruding portion provided so as to protrude upward in the recessed portion; When,
A housing having an opening;
Scanning means for creating a digital image by scanning a document supported in the housing by the document holder;
A discharge unit that has a pair of rollers for holding the document holder up and down, conveys the document holder in a horizontal direction, and discharges the document holder from the opening;
A document reading device provided with a fulcrum portion located below the path along which the document holder is conveyed in the housing and positioned on the opening side of the roller pair;
When the concave portion of the document holder is transported to the nipping position by the roller pair, the document holder, which cannot be nipped by the roller pair, is tilted by its own weight with the support position by the fulcrum portion serving as a fulcrum, and the protruding portion Is held by an upper roller of the roller pair .

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