JPH0797811B2 - Image reader - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image reading device for reading character or graphic information on a document as two-dimensional digital information, and has a document table fixed on the upper surface of a housing. The present invention relates to an image reading apparatus having a structure in which a reading mechanism for automatically feeding a sheet-shaped document is added to a so-called flat bed type image reading apparatus.

-Prior Art- A flatbed-type reading device has an advantage that it can read a book, a bound document, or the like because the document can be read while the document table is fixed and the document is fixed. However, in the case where standardized information is read one after another from a large number of cards and the like, it is necessary to obtain the cards one by one and set them on the platen, which causes a drawback that the work is complicated and inefficient.

Therefore, an apparatus has been proposed in which an automatic sheet feeder for sheet paper is provided at the end of the housing of the flatbed reader to eliminate the above-mentioned drawbacks. For example, JP-A-56-161770
In the publication, a flat-bed type facsimile transmission device equipped with a mirror that travels along a transparent platen on the upper surface of the casing of the device and reflects the light read from the platen by 90 degrees and projects it onto a one-dimensional image sensor In this case, a reading window is provided at the end of the housing in the direction of travel of the mirror, and an automatic paper feeding device for feeding a sheet-like document is provided in the reading window portion. By swinging the mirror, the light from the reading window is flattened. An image reading device having a structure for projecting onto a one-dimensional image sensor for a bed is disclosed.

-Problems to be Solved by the Invention-The present invention complicates the structure by obtaining means for automating the swinging movement of the mirror during flatbed reading and automatic sheet feeding reading in the above conventional apparatus. The purpose of the present invention is to provide an image reading device which is excellent in operability.

-Means for Solving the Problems-The present invention provides an automatic paper feeding device at the end of the housing of a flat bed type image reading device, and a document fed by the automatic paper feeding device is provided in the housing. In an image reading apparatus having a structure in which the same image sensor and optical system are used to read from a reading window provided at an end, an image sensor 18 for reading an original and an imaging lens 19 are provided in a stationary position, and a transparent original bed of a flat bed By using the movement operation of the carrier that causes the mirror to travel along the path, the swinging operation of the mirror at the time of switching the optical path is performed.

Explaining further by using the reference numerals of the illustrated embodiment, the image reading apparatus of the present invention is such that an original table 9 made of a transparent plate on the upper surface of the housing 8 and a lower surface of the original table are run to read from the original table. Mirrors 13 and 13a for reflecting light by 90 degrees and projecting the light onto the one-dimensional image sensor 18 are provided, and a reading window 34 is provided at the end of the housing 8 in the direction of mirror travel and the reading window 34 is provided.
A document passage 36 passing through a portion and a sheet-like document in the document passage
An automatic paper feeder 21 for passing 29 is provided,
In an image reading device having a structure for projecting light from the reading window 34 onto the one-dimensional image sensor 18 by swinging the mirrors 13 and 13a, the one-dimensional image sensor 18 and its imaging lens 19 are read out. The mirrors 13 and 13a are pivotally supported by the carriers 12 and 12a, and the mirrors 13 and 13a are mounted at fixed positions on the housing 8 of the mirrors 13 and 13a.
Is provided with a biasing means 40 and a positioning means 41 for holding the flatbed reading position at the flatbed reading position, and the shafts 38, 47 of the mirrors 13, 13a are provided.
A cam member 42 that comes into contact with the member 39 connected to the carrier 13 is provided at an immovable position of the carrier traveling end, and the traveling movement of the mirrors 13 and 13a at the traveling end is used to move the mirrors 13 and 13a to the carrier
It is characterized by swinging on the 2 and 12a.

-Operation- According to the above structure, the members 39 connected to the mirrors 13 and 13a by moving the carriers 12 and 12a to the moving ends thereof.
Comes into contact with the cam member 42 and swings the mirrors 13 and 13a, the optical path from the reading window 34 to the one-dimensional image sensor 18 is opened, and if the mirror 18 is moved to the transparent original table 9 side, Since 13 and 13a return to the flatbed reading side, the optical path can be automatically changed during flatbed reading and during automatic document scanning without any special operation, and no operation error occurs. . Further, in the apparatus having the above-mentioned configuration, since the reading window 34 for the automatically fed document, the imaging lens 19 and the image sensor 18 are provided at fixed positions in the housing 8 of the apparatus, the relative positional relationship with the cam member 42 is used. Even if an error occurs in the stop position at the traveling ends of the carriers 12 and 12a, the error does not affect the optical path length of the reading light L. Therefore, the mounting error of the cam member 42 and the carrier 1
The stop position error of 2 and 12a does not deteriorate the reading accuracy of the automatically fed document.

-Embodiment- FIGS. 1 to 3 are views showing a first embodiment of the present invention. FIG. 1 is a side view showing a reading state of a document on a document table 9, and FIG. FIG. 3 is a side view showing a state of reading a document fed by the feeding device 21, and FIG. 3 is a side view of a main part showing a mechanism for retracting the mirror 13 at the moving end.

In the figure, 8 is a housing of the apparatus, 9 is a document table made of a glass plate fixed to the upper surface of the housing 8, 10 is a document placed on the document table 9, and 11 is mounted parallel to the document table 9. Mounted guide rods, 12
Is a carrier that travels back and forth along the guide rod 11, 13 is a mirror mounted on the carrier 12, 14 and 14 are light sources for illuminating the document mounted on the carrier 12, and 15 is a half of the carrier 12 in the same direction. A second carrier running at a speed, 16 and 17 are intermediate mirrors mounted on the second carrier 15, 18 is an image sensor provided in an immovable position, 19 is an imaging lens, and 20 is a side part of the document table 9. It is a document holder that is pivotally attached.

The document 10 placed on the document table 9 is read as two-dimensional information by the main scanning of the image sensor 18 and the sub-scanning by the movement of the carrier 12, that is, the mirror 13. Second here
Intermediate mirrors 16 and 17 are provided on the carrier 15 and this is used as the carrier 1
The reason why the carrier travels in the same direction as 2 at a speed of 1/2 is to prevent the optical path length from the original document to the image sensor 18 to change even if the carrier 12 moves. These configurations are no different from the structure of the conventional flat bed type image reading apparatus.

Reference numeral 21 generally indicates an automatic paper feeding device provided at an end portion of the housing 8, and includes paper feeding rollers 22 and 23, an automatic paper feeding device 24, and a stacker 25. To further describe the details of the illustrated automatic paper feeder 24, 26 is a frame fixed to the housing, 27 is a hopper plate whose tip is pivotally supported by the frame 26, and 28 is the frame 26.
A pick roller axially attached to the pick roller 29, an original document stacked on the hopper plate 27, a spring 31 pressing the original document 29 against the pick roller 28, a separating roller 31 provided downstream of the pick roller 28, 3
2 is a friction pad that is elastically pressed by the separation roller 31, 33 is a paper guide, and the original document 29 sent by the pick roller 28 is
Are separated by the separation roller 31 and the friction pad 32 and fed one by one to the paper feed roller 22.

A reading window 34 is provided at the end portion of the housing provided with the automatic paper feeding device 21, and light source lamps 35, 35 for illuminating the original are provided in the vicinity of the reading window 34. 21 sheet passages 36 are formed along the reading window 34. That is, the document fed by the automatic paper feeder 24 is nipped by the paper feed rollers 22 and 23 and fed along the reading window 34, during which the image information is read and then discharged to the stacker 25. To be done. A document pressing plate 37 is provided on the back of the reading window 34.

The mirror 13 is mounted on the carrier 12 as shown in FIG.
It is fixed to the rocking frame 39, and is installed at an angle of 45 degrees by the joint action of a tension spring 40 stretched between the rocking frame 39 and the carrier 12 and a stopper 41 provided on the carrier 12. The read light L from the original 10 is directed to the intermediate mirror 16.
Bend 90 degrees.

When the carrier 12 reaches its stroke end, the cam plate 42 provided on the immovable member abuts the swing frame 39 and rotates it by about 45 degrees. The pivot shaft 38 of the swing frame 39 is below the mirror 13, and therefore, the rotation of the swing frame 39 causes the mirror 13 to retract downward. As a result, as shown in FIG. 2, an optical path from the reading window 34 to the image sensor 18 via the intermediate mirrors 16 and 17 and the imaging lens 19 is formed, and automatic feeding is performed through the paper passage 36 provided at the end of the housing. The images of the original document 29 can be sequentially read. Needless to say, the sub-scan in this case is performed by moving the document by the paper feed rollers 22 and 23.
The stop position of the carrier 12 at the stroke end is
Image sensor 1 from reading window 34 through intermediate mirrors 16 and 17
The length of the optical path reaching 8 must be equal to the length of the optical path reaching the image sensor 18 from the platen 9 through the mirrors 13, 16 and 17.

In the embodiment shown in FIGS. 4 and 5, the mirror 13a is retracted at the stroke end of the carrier 12a and at the same time the carrier 1 is moved.
By turning 2a itself by 90 degrees, the light source lamps 14, 14 mounted on the carrier 12a can be used as a lamp for illuminating a document during automatic reading.

That is, the carrier 12a is the guide rod 1 as shown in FIG.
It is pivotally supported by a pin 44 that is planted in a slide block 43 that slides on 1, and is held upright by a mechanism such as a tension spring and a stopper shown in FIG. ing. A gear 45 is fixed to the tip of the pin 44, and a pin 47 is attached to the outside of the swing frame 39a to which the mirror 13a is fixed.
A gear 46 centered on is fixed. The gear 46 meshes with the gear 45 via an intermediate gear 49, and its diameter is twice that of the gear 45. When the carrier 12a reaches the stroke end, the cam plate 42 shown in FIG. 3 comes into contact with the carrier 12a and rotates it 90 degrees so that the pin 47 moves 90 around the pin 44.
Since the gears 46 rotate about 45 degrees as shown in FIG. 4, the carrier 12a is laid down to expose the light source lamp 14 to the reading window 34 and the mirror 13a is retracted from the reading window 34 as shown in FIG. The optical path of is opened. By doing so, it is not necessary to provide the light source lamps 35, 35 provided in the first embodiment.

-Effects-As described above, the image reading apparatus of the present invention is provided with an automatic paper feeding device at the end of the housing of a flat bed type image reading apparatus, and the automatic paper feeding device continuously reads sheet-like originals. The automatic switching between flatbed scanning and automatic feed document scanning is automatically performed as the carrier moves.
There is an effect that a special operation for switching the mirror is not required, the operability at the time of motion conversion is significantly improved, and the occurrence of an operation error can be completely avoided. Further, even if an error occurs in the stop position of the carrier due to the mounting position of the cam member that swings the mirror, this error does not reduce the reading accuracy of the automatically fed document, so a troublesome adjustment work is required during assembly. High reading accuracy can be guaranteed without

[Brief description of drawings]

1 to 3 are views showing a first embodiment of the present invention,
FIG. 1 is a side view showing a reading state on a flat bed,
FIG. 2 is a side view showing a reading state by automatic feeding, and FIG. 3 is a partial side view showing a mirror mounting structure of a carrier.
FIGS. 4 and 5 are views showing a second embodiment, FIG. 4 is a side view showing an automatic feed reading state, and FIG. 5 is a perspective view showing a mounting structure of a carrier and a mirror. In the figure, 8 is a housing, 9 is a document table, 12 is a carrier, 13 is a mirror, 18 is an image sensor, 19 is an imaging lens, 21 is an automatic paper feeding device, 22 and 23 are paper feeding rollers, and 24 is automatic. Paper feeder, 2
5 is a stacker, 31 is a separating roller, 32 is a friction pad, 33 is a paper guide, 34 is a reading window, 35 is a light source lamp, 36 is a paper passage, and L is a light beam.

Claims (1)

[Claims] 1. A document table (9) comprising a transparent plate on the upper surface of a casing (8) and a document table (9) which runs along a lower surface of the document table.
And a mirror (13, 13a) for reflecting the reading light from the camera by 90 degrees and projecting the light onto the one-dimensional image sensor (18), and a reading window (34) provided at the end of the casing (8) in the mirror traveling direction. A document passage (36) passing through the reading window (34) and an automatic paper feeder (21) for passing a sheet-like document (29) are provided in the document passage, and the mirror (13, By swinging 13a) the reading window (34)
In an image reading device having a structure for projecting light from a light source onto the one-dimensional image sensor (18), the one-dimensional image sensor (18) and its imaging lens (19) are provided at a fixed position of a housing (8). , Mirror (1
3, 13a) is swingably supported by a carrier (12, 12a), and an urging means (40) and a positioning means (41) for holding the mirror (13, 13a) at a flat bed reading position are provided. The cam member (42) that is brought into contact with the member (39) connected to the shafts (38, 47) of the mirror (13, 13a) is provided at a stationary position of the carrier travel end, and the mirror (13, 13a) travels. The mirror (13, 13a) is moved to the carrier (1
2, 12a) Image reader characterized by swinging on.