JPS58142666A - Original reader - Google Patents

Abstract

PURPOSE:To read originals even when they are thick, by placing an original stationarily on the original placing plate and supporting the image pickup element by a carriage which can be moved in two directions crossing at right angles to read the original by moving the carriage. CONSTITUTION:An original O to be read is stationarily placed on an original placing glass 1 fixed to the main body 2 of an original reader. Then the original O is lightened by a small lamp 4 fixed to a movable carriage 3 and the optical image of the original O is formed on the light receiving surface of a CCD7 where numerous dot-shaped photoreceptor elements are arranged in one line by introducing the reflected light through a mirror 5 and a lens 6. The carriage 3 makes step movements in the direction normal to the Y-direction under the guidance of a guide rail 10 on a movable table 8 and, when the reading is completed from one end to the other end, the movable table 8 is moved to the Y-direction under the guidance of a rail 12 to scan again in the direction normal to the Y- direction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an original + f4m capture device for 19'rill digital copying machines, facsimile machines, etc.

In the above reading device, the image of the original to be read is formed by a lens on a solid-state imaging element such as a COD in which a large number of dot-shaped light receiving elements are arranged in the main scanning direction, and the original is conveyed in the sub-scanning direction. Alternatively, there is a known device that reads the entire document by moving the image sensor and lens together in the sub-scanning direction. A lens with a long focal length is required, which increases the size of the device, and an imaging element with a large number of light-receiving elements is required, but it is difficult and necessary to increase the number of light receiving elements, so it is difficult to increase the number of light receiving elements. The drawback is that it is difficult to improve resolution. In addition, a small imaging probe and a lens with a short focal length constitute an i'' moving absorption head, and this head moves back and forth in the main scanning direction, and the document is equally conveyed by rollers in the next scanning direction to cover the entire surface of the document. Although it is possible to remove thick originals such as books, it also has the disadvantage that extremely thin originals tend to jam in the conveyance means, and the originals tend to wrinkle. .

The main object of the present invention is to provide a document reading device that solves the various disadvantages mentioned above.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram of a wall portion of an embodiment of the present invention in the main scanning direction (X
Figure 2 is a view of the same embodiment as seen in the direction perpendicular to the scanning direction (Y direction). FIG. 3 is a perspective view of the main part of the same embodiment.

In the figure, O is the original to be read that is placed stationary on the i-wheel stand crow 1 identified in the box 2 of the main body of the original reading device 03
is a movable carriage.

A small lamp 4, a mirror 5, and a short sunspot distance lens 6.0OD7 are fixed to the carriage 3. The light from the document 0 that has been illuminated by the rung 4 is reflected by the mirror 5 parallel to the document placement surface of the document table. It is reflected in the direction and directed toward the T lens 6. The lens 6 i 00D7 forms an optical image of the document on a light receiving surface where a large number of dotted light receiving elements are arranged in a line. 0(31)7 self-scans this source in the direction in which the upper solar photoreceptors are arranged to form an electrical signal corresponding to the edge. Using these 16 images, 9 images can be printed out.

The movable carriage 3 is mounted on the movable table 8V so as to be movable in the X direction (the left-right direction in FIG. 2, which is a direction parallel to the document placement surface of the document table l). That is, 9 is a bolt bearing fixed to the carriage 3, and this bearing 9 is slidably fitted to a linear guide rail 1o fixed to the movable base 8. Rail lo is Hlf
Bt is oriented in the X direction. Therefore, when the platform 8 is returned to its original position, the carriage 3 is movable in the X direction along the guide t of the rail 10.

The carriage 3 is also movable in the Y direction (the left-right direction in FIG. 1, that is, the direction perpendicular to the previous X direction, and this direction is also parallel to the document placement surface of the document table 1). . Specifically, the movable table 8 is equipped with a sliding bearing 11 or 161, and this bearing 11 is attached to the box 2 of the main body of the apparatus. +i
The Q'-rule 12, which is attached to the fixed linear guide rail 12 on the north side of the slide wJ, is oriented in the direction of the AiJ and Y forces. Therefore, the carriage 3 is stopped relative to the table 8, and the table 8 is moved in the Y direction under the guide of the rail 120. Then, the carriage 3 is moved in the Y direction.

Now, the alignment direction of the large number of light receiving elements of 0 (Jl)7 is made to correspond to the Y direction. Tsu-1: Su, (JOD
When the light receiving elements 7 are projected onto the document placement surface of the document table 1 by the violet lens 6 and the mirror 5, the projected images of the light receiving elements are aligned in a line in the Y direction. Δl in Fig. 1 is the array length of the above-mentioned large number of light-receiving element projection images, and at one time, one station of the coarse width part of the length Δ) of the original O is (JOl) 7. The light-receiving element array I/C swims and is converted into electrical signals. The carriage 3 is then moved step by step 6 in the X direction as described above under the guidance of the vertical rail IO. Movement movement 9 that moves a predetermined minute distance in the X direction and stops for a predetermined short time
Move instead of returning. -t-L, RCA when stopped
aD performs self-scanning and scrapes a very narrow portion of the document having a length of Δl. When this reading is completed, the carry and ji3 move in the X direction by the predetermined minute distance, and this minute distance is reproduced lI! This is set in accordance with the N image quality that is added to the Il image. As described above, when the carriage 3 is moved forward in the X direction and the dirt has been removed from one end to the other end in the X direction of the area of width Δ of the document O, the carriage 3 is moved forward in the X direction. Either move backward δ and then move a distance of Δl in the Y direction, or first move a distance of Δl in the X direction, move backward in the X direction, and then move forward in the X direction again as described above. Then, an area having a width of Δl adjacent to the original area read by eye 11 is measured from one end to the other end in the X direction. Repeat this action and cool down
740 (fm Also in the Y direction, there is soot from one end to the other,
Also in the X direction, from one end to the other, the entire surface of the VC manuscript required, the taken bale, the carriage 3 is in the X direction, and the Y
It moves back in the direction and returns to the initial starting position. When the carriage 3 moves in the Y direction, the COD does not self-scan, and the original is not read.

Incidentally, the signal obtained by reading a very narrow width portion of the Ijice with a length of Δl is sent to the printer as the carriage 3 moves forward in the X direction, and the image is simultaneously reproduced. Alternatively, the above signal may be transmitted to the memory circuit as the gear ridge 3 moves forward in the
Part of the information regarding the width area of Δ is memorized in the memory circuit, and while the carriage 3 is moving back in the The image of the area may be captured, or it may be transmitted to the memory circuit as the signal station carriage 3 moves two-dimensionally, and a part of the information on the entire surface of the document is stored in the memory circuit, and after the entire surface of the document has been read. Transmit to printer -Ct
The desired image r may also be printed out.

In the above example, the backward movement speed in the X direction and the movement speed in the Y direction of the carriage 3 are faster than the forward movement speed in the Meeting hours are shortened. Alternatively, if the gear ridge 3iX is moved forward in the force direction and the entire area of width Δl from one end to the other end of the document in the X direction is read,
Next, on the forward movement end point side, move the carriage 3 forward a distance of Δl in the iY direction, and then move the carriage 3 backward in the X direction with the same step movement as in the forward movement. The movement kfey of moving a distance and stopping for a short time in the same manner as during the forward movement may be repeated, and during this backward movement also, the document may be read by self-scanning during the short time stop.

In any case, the movable reading head composed of 3 to 70 means only needs to read a small area of a document at a time, so it is small and lightweight, and can be moved reliably in steps.

Next, a mechanism for moving the carriage 3 in the X direction and the Y direction will be explained. The mechanism described below can move the carriage 3 in both the X direction and the Y direction with a single movable traction member, and there is no need to mount a motor to move the carriage 3 on the stand 8 or the carriage 3. Therefore, these iJ braking system conflicts can be reduced and the accuracy of movement can be improved.

In Fig. 3, 13 to 17 are timing pulleys, and 0 pulley 13 is a pulse motor 1 that can rotate in both forward and reverse directions.
9's output shaft is fixed to the output shaft of 0 and no! 713
．． 14 is arranged so as not to mechanically interfere with the table 8, and is therefore preferably arranged further outside of both ends of the movement range of the table 8 in the Y direction. Goo I715
, 16 and 17 are rotatably mounted on the same type of ripping shaft as in 88. The boolean lJ1.5.17 is placed on one side of the table 8 in the X direction, and the pulley 16 is placed on the other side. 7-IJ 15, 17, and pulley 16 are self-effacing so as not to mechanically interfere with the movement of the carriage 3 on the platform 8.
, 17, and the pulley 16 are preferably arranged further outside the movement range of the carriage 3 in the X direction. 18 is actually an endless timing belt and pulley 13
, 15, 16, 17°14. Between the goo IJ13 and 15, between the boots 917 and 14, and between the pulleys 14 and 13, the techelt 18 is parallel to the rail 12, in other words, it is stretched in the Y direction, while the goo IJ15,1
The belt 18 is stretched parallel to the rail 10 between '6 and between the goo IJ16 and 17, in other words, in the X direction.

The belt 18 is fixed between the pulleys 15 and 16 to a hanging plate 22 identified on the carriage 3 (see FIG. 1). Goo! The belt 18 may be fixed to the hanging plate 19 between J16 and J17.

In Figure 1, it is a 20f'i electromagnet, and the carriage 3 tl
(It is fixed. When the electromagnet 2o is activated, it is attracted to the magnetic kite rail 10 and fixes the carriage 3 so that it does not move relative to the base 8. In the case, 21 in FIG. 2 is an electromagnet, and the iJ When the zero electric stone 21 fixed to the moving table 8 is activated, it is layered on the magnetic guide rail 12, and fixes the table 8 so as not to move relative to the rail 12, in other words, with respect to the main body of the reading device. .

Now, when the reading switch is turned on, the electromagnet 21 operates to fix the table 8 in an immovable width. However, since the electromagnet 20 does not operate, the carriage 3 remains movable relative to the table 8.

Next, the pulse motor 19 is operated to drive the pulley 13 intermittently and synchronously in the counterclockwise direction. As a result, the carriage 3 moves forward (step movement) in the X direction as described above, and the area of the width t of the document is removed from one end in the X direction to the other end as described above. This process is completed. Then magnet 21
The rotational direction of the motor 19 is reversed while the magnet 20 remains inoperative, the pulley 13 is rotated in the clockwise direction, and the carriage 3 is moved back in the X direction to return to the forward movement starting position.

When the carriage 3 returns to the original forward movement starting position, the motor 19 temporarily stops, and the operation of the magnet 21 is released to allow the carriage 3 to move along the rail 12.
The carriage 3 is fixed to the table 8 by operating at 0τ.

In this state, when the motor 19 is activated and the pulley 13 is rotated counterclockwise, the stand 8 moves forward in the Y force direction while keeping the carry tip 3t-stopped on the ground.When the stand 8 moves forward a distance Δl, the motor 19 moves forward. At the same time, the magnet 21 is activated to disable 20 magnets, and the above operation is repeated again to complete the reading of the entire document, and the carriage 3 moves back in the X direction to perform the final reading. When it returns to the forward movement starting position during operation, the magnet 21 is inactive, the magnet 20 is activated, and the motor 19 rotates the pulley 13 in the direction of 1.
With the carriage 3 fixed on the ground, the Y direction 1
c) Return the carriage 3 to the forward movement starting position for the first cyst removal. In the above operation, gear ridge 3
When the carriage 3 moves backward in the X direction and forward and backward in the Y force direction, the pulse interval t of the pulse voltage applied to the motor 19 is shorter than the division of the forward movement of the carriage 3 in the X direction. By this, pulley 13 in the former case
By making the rotation speed of the latter faster than in the latter case,
The speed t1 of the backward movement of the carriage 3 in the X direction and the reciprocating movement in the Y direction is set higher than the forward movement speed in the X direction as described above.

In the above operation, when the forward movement of the gear ridge 3 in the X direction VC is completed r, it continues its backward movement δ and then moves Δl forward in the Y direction 1a.
δ, but when the forward movement of the carriage 3 in the X direction is completed, the magnet 21 is deactivated, and the magnet 2C)'
Turn the pulley 13 counterclockwise to rotate the stand 8.
is moved forward in the Y direction by Δl, the magnet 21 is activated again, the magnet 20 is deactivated, and the pulley 13 is rotated in the open direction.
The carriage 3 may be moved backward in the X direction. At this time, the pulse interval of the pulse voltage applied to the Tanabata 19 is made the same as that during the forward movement of the carriage 3, and the original is read as before when the carriage 3 moves backward in the X direction. The time required to take the entire surface of the document is further shortened.In the above example, a pulse motor was used as the motor 19, but the l)0 motor can also be used as the Tanabata 19, and the rotation angle control of this l)0 motor It is also possible to perform this using an encoder connected to the motor shaft.

Friend, in the above example, the carriage 3 is placed against the platform 8, and the carriage 3 is
Magnets 20 serve as means for fixing to the T-rails 12.
．． 21 was used, but the following means can also be adopted for the magnets 20 and 21. R11, an electromagnetic clutch is interposed between the pulley 16 and its support shaft 16', so that when the clutch is activated, the pulley 16 is fixed to the fixed shaft 16' in a non-rotatable manner, and when the clutch is not activated, it is rotatable. Make it.

On the other hand, the sliding load of the platform 8 on the rail 12 is greater than the sliding load of one carriage 3 on the rail 10 in total. Thus, when the electromagnetic clutch is not activated, the Boo IJ 13
To rotate the pulley 13 in the forward and reverse directions, the carriage 3 moves back and forth on the platform 8 while the platform 8 is stopped relative to the rail 12. If the pulley 13 is rotated in the forward and reverse directions by operating the electromagnetic clutch 1, the carriage 3 moves back and forth on the platform 8. The stand 8 reciprocates while the stand 3 is fixed to the stand 8. Therefore, the electromagnetic clutch is connected to the magnet 2o.
ON at the same time as 01! ')' will be done.

In the above example, a substantially endless belt 18 (both ends of one end belt may be connected to the hanging belt 22) is stretched to form a T-shaped closed loop, and Tanabata is also mounted on carriage 3. The tanabata carriage is moved two-dimensionally, but the movement on carriage 30 8 and the movement on table 87 can also be carried out using separate motors. .

This will be explained in FIG. FIG. 4 is an explanatory plan view of the main part thereof.

In Fig. 4, 23 is a timing pulley fixed to the output shaft of the pulse motor 25 fixed to the stand 8, and 24 is a timing pulley attached to the shaft fixed to the stand 8. . A substantially endless timing belt 26 is passed between the pulleys 23 and 24, and this belt is fixed to the hanging plate 22 of the carriage 3. No-I
J23, 24 are arranged so as not to mechanically interfere with the carriage 3, and are therefore preferably arranged further outward than the movement range of the carriage 3 in the X direction on the base 8.

Reference numeral 27 is a timing pulley fixed to the output shaft of a pulse motor 29 fixed at a fixed position, and pulley 28 is a timing pulley provided at a fixed position with a rotation capacity of 6 f. endless timing belt 3
The belt 30 is fixed to the stand 8, and the belt 30 is attached to the carriage 3 in order to read the entire document.
When performing step forward movement in the tX direction, the motor 25 is driven with the motor 29 stopped, and the pulley 23 is intermittently rotated counterclockwise. When the carriage 3 is moved back and forth in the X direction, the motor 25 is driven and the pulley 2
Rotate 3 clockwise. On the other hand, to move the platform 8 forward in the Y direction, the motor 29 is driven to rotate the pulley 2 counterclockwise, and to move the platform 8 backward, the pulley 2 is rotated clockwise.

In this example, while the pulley 23 is rotated in one direction and the carriage 3 is moved back in the X direction, the motor 29 is driven to rotate the pulley 27 counterclockwise, and the
may be moved forward in the Y direction by a distance of Δl. carriage 3
The carriage 3 must be moved in a direction that combines both the X and Y directions to reach the forward movement starting point position for ν-vertical reading, so the carriage 3 is moved backward only in the X direction and then only in the Y direction. Compared to the right-angle movement method of the carriage 3, in which the carriage 3 is first moved forward only in the Y direction and then moved backward only in the X direction, the document reading time can be reduced. Of course, when the carriage 3 moves in the X direction, the motor 29 should be stopped when the claw 9 motor 25 is activated, and when the platform 8 moves in the Y direction, that is, when the motor 29 is activated, the motor 25 should be stopped. Accordingly, the carriage 3 may be moved at right angles as in the example shown in FIG.

Incidentally, the rotation angle of the motors 25 and 29 is controlled using encoders in the same manner as described above.
You can also use a regular wire boolean instead of a timing gouger.

Moreover, open area type 00D can also be used as COD.

In addition to the normal monocular lens, the lenses in the above examples include
A bar lens, a focusing light transmission body (can also be replaced with a cell).

In any case, according to the present invention, even thick originals can be read, and since the reading head moves two-dimensionally to read the original a little, the head is lightweight, so it can move accurately and easily. This makes it possible to achieve high-speed reading and image reproduction of 1 liJ, and since it is only necessary to illuminate a small area of m documents, there is no need to correct uneven illuminance on the document surface.
Or something that is simple, has a very useful effect, or plays something.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the cost part of the embodiment of the present invention viewed in the X direction,
Fig. 2 is a view of the mounting part of the same embodiment in the Y direction, Fig. 3 is a key ridge moving mechanism -■ is a fixed m phase, 3 is a carriage, 6 is a lens, 7 is a COD, 8 is il' motion table, 10
．． 12 is a kite rail, 13 to 16 are timing pulleys, 18 is a timing belt, 19 is a motor, 23, 2
4, 27, 28 are timing pulleys, 26, 31;
t timing belt, 25.29 is the motor ◇ Applicant Canon Co., Ltd.

Claims (1)

[Claims] A document table on which a document to be copied is placed stationary, a movable carriage movable in a first direction parallel to the document table, and a second direction parallel to the document table and orthogonal to the first direction. , an image sensor supported by the movable ridge, in which a large number of point-like light receiving elements are arranged in a direction corresponding to the second direction, and converts optical information into a chemical difference signal;
The movable carriage IJ is fully equipped with an imaging optical system for forming an image of the document on the image sensor, and is supported by the movable carriage IJ, and is arranged by moving the movable carriage in a first direction to arrange the light receiving elements. a first operation of reading a document in a first direction with a width corresponding to the long type; and after the first operation is completed, the movable carriage is moved in the second direction a distance corresponding to the array length of the light receiving elements; # A document reading device that reads the sound of a document by repeating the second movement.