JPH04314256A - Picture reader - Google Patents

Abstract

PURPOSE:To prevent entering of a dust or the like from the lower side even when the picture reader is loaded into an automatic document feeding device without deviation in the relative position between a slit disk and a photosensor even in the case of pressing a handy scanner from its upper part. CONSTITUTION:A main roller 12 to generate a read timing is fitted to a side frame 35 fixed to a lower cover 33. A sensor unit 8 for reading is fitted to a side frame 35 movably in the vertical direction via a sensor cap 37. When the picture reader is loaded into an automatic document feeding device, only the sensor unit 8 and the sensor cap 37 only are moved upward.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device that reads image information on a document by moving relative to the document, and more particularly to an image reading device that is detachable from an automatic document feeder that automatically conveys the document. Regarding a reading device.

0002

[Prior Art] Conventionally, compact image reading devices (hereinafter referred to as handy scanners) that can manually read image information on a document have been put into practical use. A device that can be attached to an automatic document feeder (hereinafter referred to as ADF) has also been developed. FIG. 5 shows an example of how such a handy scanner is used alone, and FIG. 6 shows a case where the handy scanner is attached to an ADF.

In FIG. 5, a handy scanner 1 reads information on a document 2, such as a book, while moving in the direction of an arrow A. Further, in FIG. 6, the handy scanner 1 is fixed in position to the ADF 4 by the latch 3. And ADF
The information on the original document 6 is read by feeding the cut paper original 6 stacked on the paper feed plate 5 of No. 4 one by one to the reading position. The original 6 after being read is discharged onto a paper discharge plate 7. Depending on the type of document to be scanned, the handheld scanner 1
is used alone or with ADF4.

FIGS. 7 and 8 are configuration diagrams showing the internal state of the conventional handy scanner 1 when it is used alone (hereinafter referred to as handy mode). In FIG. 7, the handy scanner 1 is equipped with a contact type image sensor unit 8, and within this unit 8, a light emitting diode (LED) is installed.
The image on the document 2 illuminated by the light emitted by the light source 9 is formed onto the CCD sensor 11 by the erecting equal-magnification imaging lens 10 and is read.

[0005] The image sensor unit 8 includes a roller 12
, 13 are fixed to a side frame 14 that rotatably supports them, and is pressed downward by a spring 15. Further, below the image sensor unit 8, a dustproof glass 16 is attached to a lower cover 17.

FIG. 9 is a block diagram showing a reading timing generation mechanism of the handy scanner 1. As shown in FIG. The rotation of the roller 12 obtained by rolling over the original 2 is accelerated by a gear group 18 and transmitted to a slit disk 19 . Slit disk 19
A transmission type photosensor 20 is attached to sandwich the roller 12, and this photosensor 20 outputs a timing signal with a number of pulses proportional to the amount of rotation of the roller 12. The gear group 18 and the slit disk 19 are attached to the support plate 21 and are integrated with the image sensor unit 8 and the roller 12. In addition, the photo sensor 20 is attached to the cover 2 of the handy scanner 1 as shown in the figure.
It is fixed at 2.

Next, the reading operation when the camera is handy will be explained. When the handy scanner 1 is moved over the original 2 in the direction of arrow A shown in FIG. 9, the roller 12 rotates in the direction of arrow B. This causes the gear group 18 and the slit disk 19 to rotate, and the photosensor 20 generates a pulse as a reading timing signal. On the other hand, the light emitted by the LED 9 shown in FIG.
The image is focused on 1. It is converted into an electrical signal by the CCD sensor 11 and captured as image information in accordance with the above-mentioned reading timing signal.

FIGS. 10 and 11 show the handy scanner 1.
FIG. 4 is a configuration diagram showing a state when the ADF 4 is attached to the ADF 4 (hereinafter referred to as "standing"). In this case, the original 6 is transported by the transport rollers 23 of the ADF 4, but the original 6 is brought into contact with the glass 16 in order to improve the transport condition. However, in this case, the document surface moves to a position shorter than the focal length S of the lens 10, so that the image that was in focus when the camera was in handy mode becomes blurred. Therefore, the protrusion 2 of the ADF 4 shown in FIG.
4 pushes up the side frame 14 and the image sensor unit 8, and moves the reading focus position to the glass 16.
is being moved to the surface facing the original.

[0009]

[Problems to be Solved by the Invention] However, in the conventional device described above, the gear group and slit disk for generating the reading timing are integrated with the image sensor unit and the roller. Then, since the photosensor was attached to the upper cover, there was a problem that the optical axis position of the photosensor could not correspond to the slit position of the slit disk.

[0010] Furthermore, when the scanner is installed, the image sensor unit is pushed upward by the protrusion of the ADF, so the gap between the roller relief part of the lower cover of the handy scanner and the outer circumferential part of the roller becomes wider, making it easier for dirt and dust to enter. There was also the problem of becoming.

The present invention has been made in view of the above-mentioned problems.The purpose of the present invention is to make only the image sensor unit movable in the vertical direction, thereby reliably generating a reading timing pulse, and preventing dust and dirt even when the image sensor unit is left in a stationary position. It is an object of the present invention to provide an excellent image reading device with improved quality of image information, which prevents dust from entering.

0012

[Means for Solving the Problems] The present invention takes the following measures to solve the above problems. That is, for the first problem, a rotating body is rotated by contacting the original, the rotation is transmitted to the reading timing generator to generate the reading timing, and based on this reading timing, the reading unit rotates the rotating body on the original. In an image reading device for reading an image, a support member is provided which is fixed to a housing and rotatably supports a rotary body, and the reading unit is movable in the distance direction with respect to a document using the support member as a guide.

[0013] In addition, to solve the second problem, the present invention has a rotating body that rotates in contact with the document, is attached to a removable automatic document feeder, and is optically adjusted to the position of the document being transported by the feeder. In an image reading device that moves a reading section to adjust the focal length and read an image on a document, a support member is fixed to the housing and rotatably supports a rotating body, and the reading section is moved to the document using the support member as a guide. In contrast, it is configured to be movable in the far and near direction.

[0014]

[Operation] Next, the operation will be explained. When reading by rotating a rotating body over a document, the rotating body is fixed to the housing by the support member even if the device is pressed from above, so the relative positional relationship between the rotating body and the reading timing generator remains unchanged. Therefore, generation of read timing is performed accurately. Furthermore, when the reading device is mounted on an automatic document feeder, the reading section is moved to align the reading focal point with the surface of the document. At this time, the reading section is guided by the first support member and moves. The support member does not move, and the gap between the rotating body attached to the support member and the casing does not widen.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

[0016] Elements common to each drawing are designated by the same reference numerals. FIGS. 1 and 2 are cross-sectional views showing an embodiment of the present invention, both of which show a handheld state.

In both figures, the housing of the handy scanner 31 is composed of an upper cover 32 and a lower cover 33. A sub roller 34 is rotatably attached to the lower cover 33, a dustproof glass 16 is attached, and a side frame 35 is integrally provided. The main roller 12 is rotatably attached to the side frame 35, and a groove 36 is formed as shown in FIG. The sensor cap 3 is installed in the groove 36 of the side frame 35.
A part of 7 is sandwiched so as to be movable in the vertical direction. As shown in FIG. 2, a pair of sensor caps 37 are provided on the left and right sides, and a contact type image sensor unit 8 is provided in the sensor caps 37 so as to cover both longitudinal ends thereof. Therefore, the image sensor unit 8 is movable in the vertical direction together with the sensor cap 37. A spring 15 is attached between the side frame 35 and the sensor cap 37, and presses down the sensor cap 37 and the image sensor unit 8. The lower end of the image sensor unit 8 comes into contact with the lower cover 33 to maintain an appropriate focal length S.

Inside the image sensor unit 8, as in the conventional example, an LED 9, an erecting equal-magnification imaging lens 10, and a C
CD sensors 11 are respectively arranged at predetermined positions.

In FIG. 1, a control board 38 is fixed to the upper cover 32, and a transmission type photosensor 20 is fixed to this control board 38. The photosensor 20 is attached to sandwich a slit disk 19, and the slit disk 19 is rotated by the rotation of the roller 12 by a gear group (not shown). This slit disk 19
And the photosensor 20 generates a read timing pulse.

Next, the reading operation when the camera is handy will be explained. In the handheld mode, as shown in FIG. 1, the lower end of the image sensor unit 8 hits the lower cover 33 due to the tension of the spring 15, so that the focal length S is adjusted so that the image on the document 2 is focused on the CCD sensor 11. is maintained. At this time, a gap g is maintained between the original 2 and the dustproof glass 16 by the main roller 12 and the sub roller 34. In this state, the document 2 is read.

The handy scanner 31 is indicated by arrow A in FIG.
When the main roller 12 is moved in the direction of the arrow B, the main roller 12 rotates on the document 2 in the direction of the arrow B. The rotation of the main roller 12 is transmitted to the slit disk 19 by a gear group (not shown). By passing through the slit 19a of the slit disk 19, the photosensor 20 outputs a timing signal with a number of pulses proportional to the amount of rotation of the main roller 12.

On the other hand, the LED in the image sensor unit 8
The light irradiated by the lens 9 is reflected on the original 2 and is reflected by the lens 10.
An image is formed on the CCD sensor 11. Image signal is CCD
The sensor 11 converts it into an electrical signal, and the photo sensor 20 captures it as image information in accordance with a reading timing signal.

Even if the upper cover 32 is pressed from above, since the main roller 12 is supported by the side frame 35 fixed to the lower cover 33, the main roller 12 will move upward relative to the upper cover 32. The photosensor 20 and the slit disk 19 are maintained in an appropriate positional relationship without any interference.

FIGS. 3 and 4 are configuration diagrams showing the embodiment when the apparatus is stationary. Next, the status and reading operation when the apparatus is stationary will be explained.

In both figures, the handy scanner 31 is
When attached to DF30, latches 39, 40 of ADF30
The handy scanner 31 is fixed in position. Further, the image sensor unit 8 slides with the sensor cap 37 with respect to the side frame 35 by the protrusion 24 of the ADF 30 shown in FIG. 4, and is pushed upward by the distance of the gap g shown in FIG. is brought into contact with the glass 16. Therefore C
The distance from the CD sensor 11 to the original 6 is set to the focal length S of the lens 10. At this time, since the side frame 35 is fixed to the lower cover 33, it does not move upward. In this state, the original 6 is read.

Next, the reading operation when the device is stationary will be explained with reference to FIG.

When the document 6 is fed from the paper feed stacker 41 and a paper feeding start operation is performed, the paper feed roller 42 is rotated by a motor (not shown), and the feed roller 42 is rotated to convey the fed document 6, and the registration roller, which has stopped rotating, is rotated by a motor (not shown). The leading edge of the document 6 enters between the main roller 43 and the main roller 12. After correcting the skew, the registration roller 43, the conveyance roller 23, and the discharge roller 44 are rotated in the directions of the arrows. A reading timing pulse is generated in the ADF 30 in synchronization with the rotation of a motor (not shown), and the image signal formed on the CCD sensor 11 when the original 6 is conveyed under the glass 16 is generated by this pulse. Each line is captured in accordance with the reading timing. The read original 6 is conveyed to a paper discharge stacker 45 by a discharge roller 44.

[0028] In the above embodiment, the original is conveyed while being in contact with the dustproof glass when it is placed, but the present invention is not limited to this, and the original may be conveyed without coming into contact with the glass.

Furthermore, in the above embodiment, the glass does not come into contact with the document even if the upper cover is pressed when the document is handy, so it is effective in preventing the glass from being scratched or soiled even if there are staples or dirt on the document. be.

[0030]

As described in detail above, according to the present invention, even when the handy scanner is pressed from above, the relative positional relationship between the roller and the photo sensor for obtaining the reading timing does not change, so that accurate reading can be achieved. This enables accurate reading timing and high-quality image reading.

In addition, when the image sensor unit is installed in the ADF, only the image sensor unit moves upward and the rollers do not move, so the gap between the outer circumference of the roller and the roller relief part of the lower cover does not widen, preventing dirt and dust from entering. This has the effect of making it more difficult.

[Brief explanation of drawings]

[Fig. 1] A configuration diagram showing an embodiment according to the present invention.

[Fig. 2] A configuration diagram showing an embodiment according to the present invention.

[Figure 3] Configuration diagram showing an example when installed

[Figure 4] Configuration diagram showing an example when installed

[Figure 5] Explanatory diagram showing an example of how the handy scanner is used alone

[
Figure 6: External view showing the handy scanner attached to the ADF

[Figure 7] Configuration diagram showing a conventional handy scanner

[Figure 8]
Configuration diagram showing a conventional handy scanner

FIG. 9 is a configuration diagram showing a conventional read timing generation mechanism

[Figure 10] Configuration diagram showing a conventional handy scanner when stationary

[Figure 11] Configuration diagram showing a conventional handy scanner when stationary

[Explanation of symbols]

2 Manuscript 6 Manuscript 8 Image sensor unit 12 Main roller 19 Slit disk 20 Photo sensor 30 ADF 31 Handy scanner 32 Upper cover 33 Lower hippopotamus 35 Side frame 37 Sensor cap

Claims (2)

[Claims] Claim 1: Image reading in which a rotating body is rotated in contact with a document, the rotation is transmitted to a reading timing generation section to generate a reading timing, and an image on the document is read by the reading section based on the reading timing. What is claimed is: 1. An image reading device comprising: a support member fixed to a housing and rotatably supporting a rotating body; and a reading unit configured to be movable in a direction toward and away from a document using the support member as a guide. 2. A rotary body that rotates in contact with the original, is attached to a removable automatic document feeder, and the optical reading unit is moved relative to the position of the original being fed by the feeder to focus. In an image reading device that adjusts the distance and reads an image on a document, a support member is provided that is fixed to the housing and rotatably supports a rotary body, and the reading unit can be moved in the distance direction relative to the document using the support member as a guide. An image reading device characterized by comprising: