JP3522364B2 - Traveling body drive of image reading device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving body driving device for an image reading device.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 5-236218 aims at downsizing and cost reduction of an image reading apparatus by sharing a sub-scanning system in a reflective original reading system and a transparent original reading system. In an image reading apparatus having a light source and a document table which are separately used for reading a reflective original and a transparent original, a mode for reading a reflective original and a mode for reading a transparent original such as a film can be selected. There is described a document table for reading a transparent original such as the above, which is installed on either one of the first traveling body and the second traveling body for reading the reflective original.

In Japanese Patent Application No. 4-338218, 2
In a traveling body driving device of an image reading device that drives two traveling bodies at a speed of 2: 1 to read an original, a steel belt is used instead of the traveling body driving wire, and one of the two traveling bodies is used. It has been proposed that the sub-scanning drive is made highly accurate by being driven by a linear motor or an ultrasonic motor.

Further, in order to perform accurate sub-scanning control at the time of reading each of a transparent original and a reflective original, a plurality of sub-scans are provided in the traveling body driving device of the image reading apparatus disclosed in Japanese Patent Laid-Open No. 5-236218. It has been proposed that the feedback control linear encoders are installed separately in the vertical direction and the sub-scanning control is performed by correcting these output signals based on the mechanical arrangement. Further, as a method usually used in the sub-scanning control, a linear encoder is installed at any one position to detect the speed and position of the sub-scanning, and a feedback signal from the linear encoder is used to drive the vehicle driving motor. There is a method of controlling.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
Japanese Patent Application No. 4-33
In the moving body driving device of the image reading apparatus described in Japanese Patent No. 8218, regarding the relationship between the feedback signal from the encoder that detects the speed and position of the sub-scanning and the actual speed and position of the moving body at the document reading position, , Not touched. Usually, the above method is often used in the sub-scanning control. However, in the above method, a linear encoder is installed at any one position to detect the speed and position of the sub-scanning, and the traveling body drive motor is controlled using the feedback signal from this linear encoder. If the position and the reading position of the transparent original or the reflective original are deviated in the vertical direction, there is a drawback that the output signal of the linear encoder is not an accurate feedback signal. In reality, it is extremely difficult to accurately align the position of the linear encoder with the reading position of the transparent original or the reflective original. Therefore, accurate sub-scanning drive cannot be performed.

Therefore, in the traveling body drive unit of the image reading apparatus described in the above-mentioned Japanese Patent Laid-Open No. 5-236218,
It has been proposed that a plurality of sub-scanning feedback control linear encoders are installed separately in the vertical direction and the sub-scanning control is performed by correcting these output signals based on a mechanical arrangement. Although the traveling body driving device of this image reading device is effective, since the correction value of the output signal of the linear encoder is obtained in advance, erroneous sub-scanning control can be performed when the target state of sub-scanning control changes. It has the drawback of going.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a traveling body driving device for an image reading apparatus, which can improve the above-mentioned drawbacks and can perform accurate sub-scanning driving even when the state of the sub-scanning control target changes. .

[0008]

In order to achieve the above object, the invention according to claim 1 is the first invention in which a reflection original is placed.
The platen and the first platen for illuminating the reflection original on the first platen.
1 light source and reflection from the reflective original on the first original table
Photoelectricity in which light is imaged via the reflection original reading optical system
It is supported by the conversion element and the guide shaft, and is supported along the guide shaft.
And moves to move the first light source and the reflected original reading light.
A part of the academic system is held and the sub-scanning is driven at a predetermined speed.
1 The traveling body and the guide supported by the guide shaft
Another one of the reflection original reading optical systems which moves along the axis
The first traveling body at a speed half that of the first traveling body.
The second traveling body, which is driven in the sub-scanning direction in the same direction as the traveling body,
A second manuscript table on which an excessive manuscript is placed, and the second manuscript table.
A second light source for illuminating the upper transparent original, and the second original
Image the transmitted light from the transparent original on the table on the photoelectric conversion element
A second document table having a transparent document reading optical system
Installed on the second traveling body and driven in the sub-scanning direction to
Image reading that selectively scans and scans transparent documents
In the traveling body drive device of the picking device, the second document table is provided.
Or, the height of the transparent document setting position with respect to the second traveling body
First linear installed at a position equal to or almost equal to
Encoder and this first linear encoder and up and down direction
Is installed separately from the first traveling body and a reflection document is installed on the first traveling body.
Installed at a position that is equal to or nearly equal to the height of the placement position
2 linear encoder and the first traveling body at a predetermined speed
Sub-scanning drive with the second traveling body to the first traveling
Run side by side in the same direction as the first running body at half the speed of the line body
Equipped with a linear DC motor that drives scanning
When the output signal of the first linear encoder is
Note: Obtain the speed information of the second traveling body, and add this speed information to
The radius of curvature of the guide shaft, the guide shaft and the first relief
Vertical distance from the near encoder, the first linear
Between the encoder and the reflection document setting position of the second document table
The reflection original is multiplied by a constant determined by the vertical spacing.
Converted to virtual speed information of the first traveling body at the installation position
Then, based on the difference between this virtual speed information and the target value,
The control voltage value of the linear DC motor is obtained.

According to a second aspect of the present invention, a reflection original is placed on it.
On the first platen and the reflection original on the first platen.
A first light source for illuminating and a reflection original on the first platen.
The reflected light is imaged via the reflective original scanning optical system.
And a photoelectric conversion element supported by a guide shaft.
The first light source and the reflective original reading
Holds part of the sampling optical system and drives the sub-scan at a predetermined speed
Is supported by the first traveling body and the guide shaft.
The reflection original reading optical system that moves along the guide axis
Holds another part of the first traveling body at half the speed
Second travel driven in the sub-scanning direction in the same direction as the first travel body
The body, a second document table on which a transparent document is placed, and the second document table.
A second light source for illuminating a transparent original on the original table,
2 The transmitted light from the transparent original on the original table is converted into a photoelectric conversion element.
An optical system for reading a transparent original for forming an image,
The document table of the
Selectively scan the projected original and the transparent original
In the traveling body driving device of the image reading device, the second
Place the transparent original on the original table or the second running body
First installed at a position equal to or approximately equal to the height of the position
Linear encoder and this first linear encoder
Installed vertically and separated from the first traveling body.
Installed at a position that is equal to or nearly equal to the height of the original placement position
The second linear encoder and the first traveling body
The sub-scanning drive is performed at a constant speed and the second traveling body is moved forward.
The same speed as the first running body at half the speed of the first running body
Equipped with a linear DC motor for sub-scanning
When reading the draft, the output signal of the second linear encoder
Information of the speed of the first traveling body from the
Information, the radius of curvature of the guide shaft, the guide shaft and the front
Vertical distance to the second platen or the second running body
Away from the transparent document setting position of the second document table and the second document setting position.
A constant determined by the vertical distance from the linear encoder
And place the transparent original on the second platen at the transparent original setting position.
Converted to the virtual speed information of the second traveling body,
The linear DC motor based on the difference between the information and the target value
The control voltage value of is calculated .

According to a third aspect of the present invention, a reflection original is placed on the document.
On the first platen and the reflection original on the first platen.
A first light source for illuminating and a reflection original on the first platen.
The reflected light is imaged via the reflective original scanning optical system.
And a photoelectric conversion element supported by a guide shaft.
The first light source and the reflective original reading
Holds part of the sampling optical system and drives the sub-scan at a predetermined speed
Is supported by the first traveling body and the guide shaft.
The reflection original reading optical system that moves along the guide axis
Holds another part of the first traveling body at half the speed
Second travel driven in the sub-scanning direction in the same direction as the first travel body
The body, a second document table on which a transparent document is placed, and the second document table.
A second light source for illuminating a transparent original on the original table,
2 The transmitted light from the transparent original on the original table is converted into a photoelectric conversion element.
An optical system for reading a transparent original for forming an image,
The document table of the
Selectively scan the projected original and the transparent original
In the traveling body driving device of the image reading device, the second
At any height with respect to the platen or the second running body
The installed first linear encoder and the first traveling
The second linear enco installed at an arbitrary height with respect to the body
And the first traveling body are sub-scanning driven at a predetermined speed.
At the same time, the second traveling body is driven at a speed half that of the first traveling body.
Linearly driven in the sub-scanning direction in the same direction as the first traveling body.
It is equipped with a DC motor, and when reading a reflective original, the
From the output signal of the linear encoder 1 of the second traveling body
Obtain the speed information, and add this speed information to the guide shaft
Radius of curvature, the guide shaft and the first linear encoder
And the vertical distance between the first document table and the reflection document installation
Vertical gap between the position and the first linear encoder
Multiplied by a constant determined by
Converted to the speed information of the second traveling body at the installation position,
Based on the difference between the speed information and the target value,
The control voltage value of the flow motor, or
From the output signal of the near encoder, the speed of the first traveling body
Information is obtained, and the curvature half of the guide shaft is added to this speed information.
Diameter, above the guide shaft and the first linear encoder
The distance in the downward direction, the position of the reflection original on the first platen, and
A vertical interval from the first linear encoder,
First linear encoder and the second linear encoder
The multiplying the vertical determined circle constant the distance between the first
Speed of the second traveling body at the reflection original setting position on the original platen
The difference between this virtual speed information and the target value
The control voltage value of the linear DC motor is obtained based on
When reading a transparent original, the first linear encoder is used.
The speed information of the second traveling body is obtained from the output signal of
The information of the speed of the guide, the radius of curvature of the guide shaft, the guide
The vertical distance between the shaft and the first linear encoder,
Transmission of the first linear encoder and the second platen
Apply a constant determined by the vertical distance from the original setting position.
The second document at the transparent document setting position on the second document table
Converted to the speed information of the running body, this speed information and target value
The control voltage value of the linear DC motor based on the difference between
Or the output of the second linear encoder
Information on the speed of the first traveling body is obtained from the signal, and this speed is calculated.
Information, the radius of curvature of the guide shaft, the guide shaft and the front
The vertical distance from the first linear encoder,
1 linear encoder and transparent original document setting of the second original table
The vertical distance from the mounting position, the first linear encoder
The vertical distance between the da and the second linear encoder.
Multiply by a constant determined by
Converted to the information of the speed of the second traveling body at the stationary position,
The linear DC based on the difference between the speed information and the target value
The control voltage value of the motor is obtained.

According to a fourth aspect of the invention, a reflective original is placed on the document.
On the first platen and the reflection original on the first platen.
A first light source for illuminating and a reflection original on the first platen.
The reflected light is imaged via the reflective original scanning optical system.
And a photoelectric conversion element supported by a guide shaft.
The first light source and the reflective original reading
Holds part of the sampling optical system and drives the sub-scan at a predetermined speed
Is supported by the first traveling body and the guide shaft.
The reflection original reading optical system that moves along the guide axis
Holds another part of the first traveling body at half the speed
Second travel driven in the sub-scanning direction in the same direction as the first travel body
The body, a second document table on which a transparent document is placed, and the second document table.
A second light source for illuminating a transparent original on the original table,
2 The transmitted light from the transparent original on the original table is converted into a photoelectric conversion element.
An optical system for reading a transparent original for forming an image,
The document table of the
Selectively scan the projected original and the transparent original
In the traveling body driving device of the image reading device, the second
Place the transparent original on the original table or the second running body
First installed at a position equal to or approximately equal to the height of the position
Linear encoder and this first linear encoder
Installed vertically and separated from the first traveling body.
Installed at a position that is equal to or nearly equal to the height of the original placement position
The second linear encoder and the first traveling body
The sub-scanning drive is performed at a constant speed and the second traveling body is moved forward.
The same speed as the first running body at half the speed of the first running body
Equipped with a linear DC motor that drives in the sub-scanning direction
When reading a draft, the output signal of the first linear encoder
Information of the speed of the second traveling body from the
The information includes the radius of curvature of the guide shaft, the guide shaft and the
The vertical distance from the first linear encoder, the first
Linear encoder and reflective document installation on the second platen
New by multiplying by a constant determined by the vertical distance from the position
Information on the new target speed, and
Based on the difference from the speed information of the second traveling body,
A) The control voltage value of the DC motor is obtained.

According to a fifth aspect of the invention, a reflective original is placed on the document.
On the first platen and the reflection original on the first platen.
A first light source for illuminating and a reflection original on the first platen.
The reflected light is imaged via the reflective original scanning optical system.
And a photoelectric conversion element supported by a guide shaft.
The first light source and the reflective original reading
Holds part of the sampling optical system and drives the sub-scan at a predetermined speed
Is supported by the first traveling body and the guide shaft.
The reflection original reading optical system that moves along the guide axis
Holds another part of the first traveling body at half the speed
Second travel driven in the sub-scanning direction in the same direction as the first travel body
The body, a second document table on which a transparent document is placed, and the second document table.
A second light source for illuminating a transparent original on the original table,
2 The transmitted light from the transparent original on the original table is converted into a photoelectric conversion element.
An optical system for reading a transparent original for forming an image,
The document table of the
Selectively scan the projected original and the transparent original
In the traveling body driving device of the image reading device, the second
Place the transparent original on the original table or the second running body
First installed at a position equal to or approximately equal to the height of the position
Linear encoder and this first linear encoder
Installed vertically and separated from the first traveling body.
Installed at a position that is equal to or nearly equal to the height of the original placement position
The second linear encoder and the first traveling body
The sub-scanning drive is performed at a constant speed and the second traveling body is moved forward.
The same speed as the first running body at half the speed of the first running body
Equipped with a linear DC motor for sub-scanning
When reading the draft, the output signal of the second linear encoder
Information on the speed of the first traveling body from the
Information, the radius of curvature of the guide shaft, the guide shaft and the front
In the vertical direction with respect to the second platen or the second traveling body.
The distance, the transparent document setting position of the second document table and the second
Is determined by the vertical distance from the linear encoder of
Multiply it by the number to get the new target speed information
The difference between the speed information and the speed information of the first traveling body
Based on this, the control voltage value of the linear DC motor is obtained.

According to a sixth aspect of the invention, a reflective original is placed on the document.
On the first platen and the reflection original on the first platen.
A first light source for illuminating and a reflection original on the first platen.
The reflected light is imaged via the reflective original scanning optical system.
And a photoelectric conversion element supported by a guide shaft.
The first light source and the reflective original reading
Holds part of the sampling optical system and drives the sub-scan at a predetermined speed
Is supported by the first traveling body and the guide shaft.
The reflection original reading optical system that moves along the guide axis
Holds another part of the first traveling body at half the speed
Second travel driven in the sub-scanning direction in the same direction as the first travel body
The body, a second document table on which a transparent document is placed, and the second document table.
A second light source for illuminating a transparent original on the original table,
2 The transmitted light from the transparent original on the original table is converted into a photoelectric conversion element.
An optical system for reading a transparent original for forming an image,
The document table of the
Selectively scan the projected original and the transparent original
In the traveling body driving device of the image reading device, the second
At any height with respect to the platen or the second running body
The installed first linear encoder and the first traveling
The second linear enco installed at an arbitrary height with respect to the body
And the first traveling body are sub-scanning driven at a predetermined speed.
At the same time, the second traveling body is driven at a speed half that of the first traveling body.
Linearly driven in the sub-scanning direction in the same direction as the first traveling body.
It is equipped with a DC motor, and when reading a reflective original, the
From the output signal of the linear encoder 1 of the second traveling body
Obtain the speed information, and use the guide shaft
Radius of curvature, the guide shaft and the first linear encoder
And the vertical distance between the first document table and the reflection document installation
Vertical gap between the position and the first linear encoder
Multiply the constant determined by to obtain new target speed information,
This new target speed information and the speed information of the second traveling body.
Control voltage of the linear DC motor based on the difference between
Calculate the value or output the second linear encoder.
The target speed is obtained by obtaining the speed information of the first traveling body from the force signal.
The degree of curvature includes the radius of curvature of the guide shaft and the guide shaft.
A vertical distance from the first linear encoder,
The position of the reflection original on the first platen and the first linear error
The vertical spacing from the encoder, the first linear encoder
Vertical distance between the feeder and the second linear encoder
Is multiplied by a constant which is determined by a new shelf target speed of the information,
This new target speed information and the speed information of the first traveling body.
Control voltage of the linear DC motor based on the difference between
The value is calculated and the first linear
Information on the speed of the second traveling body from the output signal of the encoder
To obtain the target velocity information, the radius of curvature of the guide shaft,
Upper and lower parts of the guide shaft and the first linear encoder
Distance, the first linear encoder and the second source
Determined by the vertical distance from the transparent document installation position on the draft table.
The new target speed information is multiplied by the constant
Difference between target speed information and speed information of the second traveling body
The control voltage value of the linear DC motor is obtained based on
Alternatively, from the output signal of the second linear encoder
Information on the target speed is obtained by obtaining information on the speed of the first traveling body.
The radius of curvature of the guide shaft, the guide shaft and the first
Vertical distance from the linear encoder of the
Near encoder and transparent document setting position of the second document table
The vertical gap between the first linear encoder and the front
Depending on the vertical distance from the second linear encoder
Multiply the whole constant to obtain new target speed information,
Difference between the target speed information and the speed information of the first traveling body
Determine the control voltage value of the linear DC motor based on
It is those that.

[0014]

According to the invention of claim 1, the linear DC motor is
The first traveling body is driven in the sub-scan at a predetermined speed, and the second traveling body is driven.
Same speed as the first running body at half the speed of the first running body
Direction sub-scanning drive. When scanning reflective originals, the first
From the output signal of the linear encoder of
Information is sought, and this velocity information contains the curvature half of the guide axis.
Diameter, the vertical direction of the guide shaft and the first linear encoder
Distance, first linear encoder and second platen reflector
It is multiplied by a constant determined by the vertical distance from the draft installation position.
Information on the virtual speed of the first traveling body at the reflection original setting position.
Is converted into information and the difference between this virtual speed information and the target value is calculated.
Based on this, the control voltage value of the linear DC motor is obtained.

According to the second aspect of the invention, the linear DC motor is used.
The sub-scanning drive of the first traveling body at a predetermined speed
The second traveling body and the first traveling body at half the speed of the first traveling body
Sub-scanning drive is performed in the same direction. When scanning transparent originals,
From the output signal of the second linear encoder,
Speed information is required, and this speed information is used for the guide shaft
Radius of curvature, guide axis and second platen or second running body
And the vertical distance between them and the position of the transparent original on the second platen
And the vertical interval between the second linear encoder and
The transparent original setting position of the second platen multiplied by the whole constant
Is converted into virtual speed information of the second traveling body in
Based on the difference between the speed information and the target value, the linear DC
The control voltage value of the controller is obtained.

According to the third aspect of the invention, the linear DC motor is used.
The sub-scanning drive of the first traveling body at a predetermined speed
The second traveling body and the first traveling body at half the speed of the first traveling body
Sub-scanning drive is performed in the same direction. When scanning reflective originals,
From the output signal of the first linear encoder,
Degree information is required.
Index radius, upper and lower of the guide axis and the first linear encoder
Direction, the position of the reflection original on the first platen, and the first
The constant determined by the vertical distance from the near encoder is
The second run at the position where the reflection original is placed on the first original table
Converted to speed information of line body, this speed information and target value
The control voltage value of the linear DC motor is calculated based on the difference between
Output signal of the second linear encoder
The speed information of the first traveling body is obtained from the
The radius of curvature of the guide shaft, the guide shaft and the first linear axis
Vertical distance from the encoder, reflection original on the first platen
Between the installation position and the vertical direction of the first linear encoder
, First linear encoder and second linear encoder
Is multiplied by a constant determined by the vertical distance between
Information on the speed of the second traveling body at the position where the reflection original is set on the original platen
Is converted into information and the difference between this virtual speed information and the target value is calculated.
The control voltage value of the linear DC motor is calculated based on
Output of the first linear encoder when scanning over originals
Information on the speed of the second traveling body is obtained from the signal, and this speed is calculated.
Information, the radius of curvature of the guide shaft, the guide shaft and the first linear
Vertical distance from encoder, first linear encoder
The vertical direction between the feeder and the transparent document setting position on the second platen.
A constant determined by the interval is multiplied and the second platen is transparent.
Converted to the speed information of the second running body at the document setting position,
Linear DC based on the difference between this speed information and the target value
The control voltage value of the motor is calculated, or the second linear
From the output signal of the encoder, the speed information of the first traveling body
The velocity of curvature of the guide axis and the
The vertical distance between the id axis and the first linear encoder,
Placement of transparent originals on the first linear encoder and the second platen
The vertical spacing between the position and the first linear encoder
Determined by the vertical distance from the 2 linear encoder
Multiplied by a constant, the transparent original setting position on the second platen
Converted to the speed information of the second traveling body, and with this speed information
Control voltage of linear DC motor based on difference from target value
Value is required.

According to a fourth aspect of the invention, a linear DC motor is used.
The sub-scanning drive of the first traveling body at a predetermined speed
The second traveling body and the first traveling body at half the speed of the first traveling body
Sub-scanning drive is performed in the same direction. When scanning reflective originals,
From the output signal of the first linear encoder,
Degree information is required, and the guide axis
Index radius, upper and lower of the guide axis and the first linear encoder
The distance between the first linear encoder and the second platen
The constant determined by the vertical distance from the original placement position is
It is multiplied by the new target speed information and this new eye
Based on the difference between the speed information and the speed information of the second traveling body
Then, the control voltage value of the linear DC motor is obtained.

According to the invention of claim 5, a linear DC motor is used.
The sub-scanning drive of the first traveling body at a predetermined speed
The second traveling body and the first traveling body at half the speed of the first traveling body
Sub-scanning drive is performed in the same direction. When scanning transparent originals,
From the output signal of the second linear encoder,
The speed information is calculated, and the target speed information is added to the guide axis
Radius of curvature, guide axis and second platen or second running body
And the vertical distance between them and the position of the transparent original on the second platen
And the vertical interval between the second linear encoder and
It is multiplied by a whole constant to obtain new target speed information.
New target speed information and the speed information of the first traveling body
The control voltage value of the linear DC motor is calculated based on the difference between
To be

According to a sixth aspect of the invention, a linear DC motor is used.
The sub-scanning drive of the first traveling body at a predetermined speed
The second traveling body and the first traveling body at half the speed of the first traveling body
Sub-scanning drive is performed in the same direction. When scanning reflective originals,
From the output signal of the first linear encoder,
Degree information is required, and the guide axis
Index radius, upper and lower of the guide axis and the first linear encoder
Direction, the position of the reflection original on the first platen, and the first
The constant determined by the vertical distance from the near encoder is
It is multiplied by the new target speed information and this new eye
Based on the difference between the speed information and the speed information of the second traveling body
The control voltage value of the linear DC motor is calculated.
From the output signal of the second linear encoder to the first traveling body.
Speed information is required, and the guide speed is added to the target speed information.
Radius of curvature, above guide axis and first linear encoder
Downward distance, the position of the reflection original on the first platen and the first
Vertical spacing from the linear encoder of the first linear
Vertical distance between the encoder and the second linear encoder
Information on new target speed multiplied by a constant determined by the separation
And the new target speed information and the speed of the first traveling body.
Control voltage of the linear DC motor based on the difference from the information
The value is calculated, and the first linear
Information on the speed of the second traveling body is obtained from the output signal of the encoder.
Information on the target speed, the radius of curvature of the guide shaft,
The vertical distance between the drive shaft and the first linear encoder,
Transparent encoder setting position of the linear encoder of 1 and the second platen
The new value is multiplied by a constant determined by the vertical spacing between
This is the new target speed information.
Based on the difference between the speed information of the
Flow motor control voltage value is calculated, or the second
Information on the speed of the first traveling body from the output signal of the near encoder
Is calculated, and the radius of curvature of the guide axis,
Vertical distance between the guide shaft and the first linear encoder
Separated, transparent originals of the first linear encoder and the second platen
Vertical spacing from the installation position, first linear encoder
And the distance between the second linear encoder and the vertical direction
It is multiplied by a whole constant to obtain new target speed information.
Of the new target speed information of the
The control voltage value of the linear DC motor is calculated based on the difference.
Be done.

[0020]

FIG. 2 shows an example of an image reading apparatus capable of reading a transparent original and a reflective original to which the present invention is applied.
In FIG. 2, reference numeral 1 denotes an original table made of a contact glass for reading a reflective original, and an original 2 for reflective reading is placed on the original table 1. Reference numeral 3 is a light source for illuminating the reflection original 2 on the original table 1. The reflected light from the reflection original 2 illuminated by the light source 3 is reflected by the reflection mirrors 4, 5 and 6 forming the reflection original reading optical system, and then read by the imaging lens 7 for reading the reflection original. An image is formed on a photoelectric conversion element for use, for example, a CCD line sensor 8 and photoelectrically converted.

Reference numeral 10 denotes a reflection mirror for switching between the reflection original reading optical system and the transmission original reading optical system, which is rotatably installed around one end 10a and is, for example, a rotation motor (not shown). The optical path is switched by being rotated by driving means such as. Here, the reflection mirror 1
In 0, the position for reading the reflective original is the solid line position shown, and the position for reading the transparent original is the broken line position 10 'shown.
Is. More specifically, the reflection mirror 10 is installed at a solid line position shown in the figure, which is substantially parallel to the reading optical axis when reading the reflection original, and forms an angle of 45 ° with the reflection original reading optical axis when reading the transparent original. Broken line position 10 '
Is installed in.

In such a structure, when reading a reflective original, the so-called first traveling body 11 on which the reflecting mirror 4 and the light source 3 are mounted and the so-called second traveling body 301 on which the reflecting mirrors 5 and 6 are mounted are indicated by A in FIG. By sub-scanning driving at a speed ratio of 2: 1 in the direction, the entire surface of the reflective original 2 can be read together with the main scanning by the CCD line sensor 8 by self-scanning.

Reference numeral 12 denotes an original table made of a contact glass for reading a transparent original, and an original 13 for transparent reading such as a film is placed on the original table 12. Reference numeral 14 is a light source for illuminating the transparent original 13 on the original table 12. The direct light from the light source 14 and the reflected light from the reflection plate 15 are reflected by the reflection plate 16 and diffused by the diffusion plate 17 to uniformly illuminate the transparent original 13 on the original table 12. The light source device for reading the transparent original, which includes the light source 14, the reflection plates 15 and 16 and the diffusion plate 17, is attached to, for example, the image reading device main body 22.

The transmitted light of the transparent original 13 uniformly illuminated through the diffusion plate 17 is reflected by the reflecting mirror 18, the imaging lens 20, the reflecting mirror 19, which is an optical system for reading the transparent original, and the broken line position 10 'in the figure. Through the reflection mirror 10 for switching the optical path, an image is formed on the photoelectric conversion element 8 that is also used for reading the reflective original and photoelectrically converted. With such a configuration, at the time of reading a transparent original, the original table 12 and the transparent original 13 are sub-scanning driven in the direction of A in the drawing, and CC
The entire transparent original 13 is read together with the main scanning by the D-line sensor 8 by self-scanning.

Here, a document table 12 for reading a transparent document is provided.
Is fixed to the second traveling body 301 for reading the reflective original, like the reflective mirrors 5 and 6 for reading the reflective original.
The second traveling body 302 for reading the reflective original is configured as a whole. As a result, the sub-scanning traveling body for reading the reflective original and the sub-scanning traveling body for reading the transparent original can be shared, and the sub-scanning traveling body for reading the transparent original can be omitted.

FIG. 1 shows a first embodiment of the present invention. This first embodiment is applied to the image reading apparatus shown in FIG. 2, and in the embodiment of the invention according to claim 1, the second drive unit uses a direct drive system as a drive source, particularly a linear DC motor. Is an example in the case of directly driving. Further, in FIG. 3, in the first embodiment, the second traveling member 302, the linear DC motor, and the second traveling member 302 for reading the reflective original, that is, the original table 12 have a height (or a height substantially equal to the transparent original setting position). Linear encoder 210 installed at the same height as the transparent document installation position)
And the first traveling body 11 and the reflection platen 1 on the first traveling body 11.
FIG. 2 is a diagram showing a relative positional relationship with a linear encoder 1001 installed at substantially the same height (or the same height as the reflection original table 1 ), and is a view of FIG. 1 viewed from the left side.

The first traveling body 11 holding the reflective original light source 3 and the reflection mirror 4 for reading the bearing 201B is Hamaawasa the first guide shaft 202. Second traveling body 301
Are the two bearings 205A, 20 on the first guide shaft 202.
5B is fitted to the two bearings 205C, 2 at the other end.
05D is in contact with the second guide shaft 203.

A drive coil 207 is attached to the lower side of the second traveling body 301 via a movable back yoke 206 for forming a magnetic circuit and a coil substrate (not shown), and the coil 207 is provided at a position facing the coil 207. The magnet 208 is also provided with a fixed back yoke 209 for forming a magnetic circuit so that the S pole and the N pole on the surface are alternately arranged in the sub scanning direction.
No. 2 is installed, and a linear DC motor is configured by them.

Further, a linear encoder 210 is installed at substantially the same height as the transparent document installation position of the second traveling body 301 on which the document table 12 is installed. In the first embodiment, a linear encoder movable portion 210A including a light source and a sensor is attached to the second traveling body 301, and the movable portion 210A is fixed to the main body 22 by a linear encoder fixed including a linear scale. Part 21
Together with 0B, a so-called optical linear incremental encoder 210 is formed.

A linear encoder 1001 is installed at substantially the same height as the reflection original table 1 of the first traveling body 11 . Here, a linear encoder movable part 1001A including a light source and a sensor is attached to the first traveling body 11, and this movable part 1001A is combined with a linear encoder fixed part 1001B including a linear scale fixed to the main body 22. Thus, a so-called optical linear incremental encoder 1001 is formed.

In this structure, when a transparent original is read, when a current is passed through the coil 207 by a control system (not shown) based on the output signal of the linear encoder 210, the second traveling body 301 with the original table 12 fixed is shown in FIG. The sub-scanning can be driven by direct drive in the direction of middle A. Here, as the linear encoders 210 and 1001, the optical type has been described, but the linear encoders 210 and 1001 are not particularly limited to this, and any other type such as a magnetic type may be used.

A first belt 212 and a second belt 213 are hung on the outer sides of the first guide shaft 202 and the second guide shaft 203 of the first traveling body 11 and the second traveling body 302, respectively. The first belt 212 and the second belt 213 are applied in exactly the same manner, such as in operation. Side views of the first belt 212 are shown in FIGS. 4 (A) and 4 (B). First belt 212
Has one end fixed to the main body 22 with the belt end 300,
A dynamic pulley 214 supported by shafts (not shown) provided on the two bearings 205A and 205B of the second traveling body 301.
It is hung around A and 214B by half a turn, and the other end is again fixed to the main body 22 by the belt end 300 ′. Similarly, the second belt 213 has a belt end at one end and a main body 22.
Is fixed to the two traveling bearings 301 of the second traveling body 301.
C and 205D are respectively wound around the moving pulleys 214C and 214D, which are supported by shafts (not shown), half a turn,
The other end is again fixed to the main body 22 at the belt end.

Dynamic pulleys 214A of the first belt 212, 2
The first traveling body 11 is clamped by a first traveling body clamp 215A at a predetermined position in an intermediate portion between 14B,
The first traveling body 11 is clamped by a first traveling body clamp 215B at a predetermined position in an intermediate portion between the moving pulleys 214C and 214D of the belt 213.

With the above construction, when the second traveling body 301 is directly driven by the linear DC motor in the direction of A in FIG. 1, the first belt 212 and the two moving pulleys 214
By the operation of A, 214B, the second belt 213 and the two moving pulleys 214C, 214D, the first traveling body 11 is driven from both sides at twice the speed of the second traveling body 302.
This enables the sub-scanning drive of the first traveling body 11 and the second traveling body 301 at a speed ratio of 2: 1. Here, FIG.
4A shows the state before the start of the sub-scan, and FIG. 4B shows the state after the end of the sub-scan. The direction A in FIG. 4 is the same as the direction A in FIG.

Here, 4 to be fitted to the first guide shaft 202
The individual bearings 201A, 201B, 205A, 205B may be, for example, a combination of a rolling bearing and a pressure member, or a sliding bearing in which a round bar and a round hole are combined. Further, the first belt 212 and the second belt 213 are not limited to metal, rubber, and other materials as long as they are belts, and wires or the like may be used.

FIG. 5 shows the control device in the first embodiment. In FIG. 5, reference numeral 501 is a microcomputer, which includes a microprocessor 502, a read only memory (ROM) 503, and a random access memory (RA).
M) 504 are connected to each other via a bus 505. A command generator 506 outputs a status command signal for commanding the status of the linear DC motor, and generates a speed command signal and the like. The output side of the command generator 506 is connected to the bus 505.

The output side of the linear encoder 210 fixed to the second traveling body 301 and the output side of the linear encoder 1001 fixed to the first traveling body 11 are interface devices 508 and 1002 for state detection, respectively.
It is connected to the. These interface devices 50
8, 1002 are linear encoders 210, 10 respectively.
01 is an interface device for processing the output signal of 01 and converting it into a digital numerical value.
A counter for counting each output pulse of 001 is provided.

Reference numeral 509 denotes an interface device for driving. The digital value of the calculation result of the microcomputer 501 is a pulse signal (control signal) for operating a power semiconductor, such as a transistor, which constitutes the driving device 510.
Convert to. The driving device 510 operates based on a pulsed signal from the interface device 509, and controls the voltage applied to the linear DC motor 511. As a result, the linear DC motor 511, that is, the sub-scanning traveling body 512 including the first traveling body 11 and the second traveling body 302 attached to the linear DC motor 511 is driven at a desired speed.

Linear DC motor 511 (sub-scanning traveling body 5)
The speed of 12) is detected by the linear encoders 210 and 1001 and the interface devices 508 and 1002,
It is taken into the microcomputer 501. It should be noted that the above is the case where the discrete type microcomputer is used, but the same applies when the command generation device 506, the drive interface device 509, and the state detection interface devices 508 and 1002 are used in one chip. It is clear that the function is obtained.

Here, in the first embodiment, the system for detecting the speed of the linear DC motor 511 (sub-scanning traveling body 512), that is, the state detecting interface device 50 for processing the output signals of the linear encoders 210 and 1001.
8, 1002 will be described. Since the operation of the state detecting interface devices 508 and 1002 is exactly the same, the state detecting interface device 508 is
And the description of the operation of the state detection interface device 1002 will be omitted.

Interface device for state detection 508
Includes a counter that sends the output pulse of the linear encoder 210 to the interrupt terminal of the microprocessor 502 and counts the reference clock (clock CLK in FIG. 6). In FIG. 6, the state immediately before the edge 601 of the output pulse OB of the linear encoder 210 arrives will be described. The counter of the state detection interface device 508 detects the cycle of the output pulse OB of the linear encoder 210 by a decrement count from a given count value (for example, 0FFFFH) based on the reference clock CLK. Output pulse O of linear encoder 210
When the edge 601 of B reaches the interrupt terminal of the microprocessor 502, the microprocessor 502 starts executing the interrupt routine shown in FIG.

The microprocessor 502 latches the decrement count value of the counter in the built-in register of the state detecting interface device 508 (P1), and the decrement count value latched in the built-in register is R.
It is stored in the AM 504 (P2). Then, the microprocessor 502 sets the count initial value (0FFFFH) for counting the cycle Tn of the output pulse OB of the linear encoder 210 to the state detection interface device 5
No. 08 counter to start decrement counting of the output pulse OB of the linear encoder 210 again (P
3), the interrupt processing ends.

When the edge 601 of the output pulse OB of the linear encoder 210 reaches the interrupt terminal of the microprocessor 502 again, the microprocessor 502 repeats the processing of P1 to P3 in FIG. At this time, the speed v2 of the linear DC motor 511 (traveling body 301) in the cycle Tn of the output pulse OB of the linear encoder 210.
10 (i) is obtained as follows.

V210 (i) = k / (Tclk × Ne × n) (1) where Tclk: period Ne of the reference clock CLK Ne: number of linear incremental encoder divisions per unit length n: reference Count number of clock CLK = 0FFFFH−
Decrement count value k: unit conversion constant to speed FIGS. 8 and 9 show the linear encoder 21 in the first embodiment.
The block configuration of the control system when the linear DC motor is driven without any correction using the outputs of 0 and 1001 is shown. In FIG. 8, reference numeral 801 denotes a linear DC motor including a sub-scanning traveling body 512 which is a control target. Information on the velocity v210 (i-1) detected by the state detection interface device 508 based on the output signal of the linear encoder 210 (not shown in FIG. 8) is given to the calculation unit 806 via the feedback loop 805. The calculation unit 806 calculates the difference e (i) between the control target value R (i) output from the command generator 506 and the information of the speed v210 (i-1) from the feedback loop 805.

This difference e (i) is integrated in a block 807, multiplied by a constant KI in a block 808, and then calculated by a calculation unit 8
09. At the same time, the difference e (i) is multiplied by a constant KP in a block 810 and given to a calculation unit 809. The arithmetic unit 809 adds the two input signals from the blocks 808 and 810 to obtain the input voltage u (i) to the linear DC motor 801.

This control voltage value u (i) is output to the linear DC motor 801, the sub-scanning traveling body 512 is sub-scanning driven by the linear DC motor 801, and the above loop is repeated. All the control calculations including the calculation of the speed detection by the linear encoder according to the above equation (1) are performed by numerical calculations in the microcomputer 501, and can be easily realized.

Further, in FIG. 9, the same symbols as those in FIG. 8 indicate the same functions, and the description thereof will be omitted. Based on the output signal of the linear encoder 1001 (not shown in FIG. 8), the information of the speed v1001 (i-1) detected by the state detection interface device 1002 is multiplied by a constant (1/2) in a block 1201. Is converted into the speed of the second traveling body 301, and is passed through the feedback loop 811 to the calculation unit 8
It is given to 06. Thereafter, the same control calculation as in FIG. 8 is performed, and the control voltage u to the linear DC motor 801 is changed.
(I) is required.

Here, the control voltage value u (i) is output to the linear DC motor 801, the sub-scanning traveling body 512 is sub-scanning driven by the linear DC motor 801, and the above loop is repeated. All the control calculations including the conversion of the speed of the first traveling body 11 to the speed of the second traveling body 301 are performed by numerical calculation in the microcomputer 501 and can be easily realized.

In the traveling body drive apparatus of this embodiment in which the guide rails 202 and 203 such as round bars are supported at almost both ends thereof, as shown in FIG. 10, guide rails (guide shafts) 202 such as round bars are provided. , 203 has a curvature of 1 due to its own weight
It is normal to have / r. Guide rail 20
If there is a curvature in 2, 203, the first traveling body 11 and the second traveling body 302 move differently. FIG. 11 shows the situation. Generally, even if the guide rails 202 and 203 have a curvature, it is quite small. Therefore, the movements of the traveling bodies 11 and 302 are rotational movements as shown in FIG. It can be regarded as an approximate translational motion.

Therefore, the second traveling body 302 is the second traveling body 302 on which the transparent document reading original table 12 is installed.
At the linear encoder 210 installed at a height equal to or approximately equal to the transparent document installation position, the radius of curvature r of the guide rails 202 and 203 and the guide rail 202,
Vertical distance f between 203 and linear encoder 210
The value obtained by adding the
It is considered that rotational movement is performed around the center point O of the curvature of 03.

In FIG. 11, e is set on the transparent original reading original table 12 or on the second traveling member 302 on which the transparent original reading original table 12 is installed at a height equal to or almost equal to the transparent original setting position. Linear encoder 2
10 is the vertical distance between the reflection original reading position. v210 is the speed measurement result by the linear encoder 210, and vref is the speed of the second traveling member 302 at the first position at the reflection original reading position of the reflection original reading original table 1.
The virtual speed converted into the speed of the traveling body 11 is shown.
This virtual speed can be expressed as vref = ((r + f−e) / (r + f)) × v210 (2) from FIG. 11. ((R + fe) / (r +
Since f)) is a constant determined only by the mechanical arrangement of the traveling body drive device, this calculation can be easily realized whether it is performed digitally or analogically.

FIG. 12 shows a block configuration of a control system in the case where the outputs of the linear encoders 210 and 1001 are corrected by the equation (2) in the first embodiment. In FIG. 12, the same symbols as those in FIG. 8 indicate the same functions, and therefore their explanations are omitted.
The speed v2 detected by the state detection interface device 508 based on the output signal of the linear encoder 210.
The information of 10 (i-1) is the constant ((r + fe) / (r +) given by the above equation (2) in block 1801.
f)) is applied to obtain information on the virtual speed vref (i-1) obtained by converting the speed of the second traveling body 302 into the speed of the first traveling body 11 at the reflection document reading position.

The information of the virtual speed vref (i-1) is given to the calculation unit 806 via the feedback loop 1802. Thereafter, the same control calculation as that of FIG. 8 is performed to obtain the control voltage u (i) to the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated. Since all the control operations including the calculation of the virtual speed vref (i-1) at the reflection original reading position by the equation (2) are performed by the numerical operation in the microcomputer 501, they can be easily realized.

FIG. 13 is a flow chart showing the operation flow of this embodiment. When the image reading device starts reading with the start button or the like, it is determined whether or not the prescan mode is set (P3301). This can be easily realized, for example, by installing a button or signal generating means for setting whether or not to perform pre-scan before image reading in the image reading device.

If it is determined in P3301 that the pre-scan mode is set, in P3302 the pre-scan control system (in the case of using the linear encoder 210, FIG.
The linear DC motor 801 is driven by the control system shown in FIG. 9 and the control system shown in FIG. Next, the microcomputer 501 determines the curvature radius r in P3303 as described later, writes it in the RAM 504, and returns to P3301.

If it is determined in P3301 that it is not in the prescan mode, that is, in the image reading mode, it is determined in P3304 whether or not the transparent original is read. This is because, for example, a button or signal generating means for setting whether to read a transparent original or a reflective original is set in the image reading device, or a read start button or a signal generating means is provided for the transparent original and the reflective original. It can be easily realized by installing separately for reading.

When it is determined in P3304 that the transparent original is read, the linear DC motor 801 is driven by the image reading control system shown in FIG. 8 in P3305 and P3306, and the sub-scanning traveling body 512 is moved. The sub-scanning drive is performed and the transparent original 13 is read. Transparent manuscript 1
When the reading of 3 is completed, the image reading operation of the image reading device is completed. On the other hand, if it is determined in P3304 that the transparent original has not been read, P330
7, the linear DC motor 801 is driven by the image reading control system shown in FIG. 12 to drive the sub-scanning traveling body 512 in the sub-scanning direction, and the reflection original 2 is read. When the reading of the reflection original 2 is completed, the image reading operation of the image reading device is completed.

Here, the radius of curvature r used in the block 1801 in the image reading control system shown in FIG. 12 at the time of reading the reflective original is the value determined in P3303, and the radius of curvature r immediately before the reading of the reflective original is used. Therefore, even if the state of the sub-scanning traveling body 512 to be controlled changes, accurate sub-scanning control can be performed, and accurate sub-scanning control can always be performed.

FIG. 14 shows the states of the sub-scanning start position and the sub-scanning end position of the sub-scanning traveling body 512 controlled by the control system shown in FIG. 8 or 9. In FIG. 14, α
Is the sub-scanning starting position of the sub-scanning traveling body 512, and β is the sub-scanning ending position of the sub-scanning traveling body 512. The output signals of the two linear encoders 210 and 1001 are output by the sub-scanning traveling body 512 to the guide shaft 2 at the start and end of the sub-scanning.
Because of the curvature of 02, 203, etc., it is inclined by θ as shown in FIG. 14, so that different values are shown as S1 and S2.

Therefore, the two linear encoders 210,
Assuming that the vertical spacing of 1001 is a and the vertical distance between the linear encoder 210 attached to the second traveling body 301 and the guide shafts 202 and 203 is f as shown in FIG. Considering that the traveling body 11 travels twice the distance of the second traveling body 301, the curvature r is approximately r = (S2 / (S2-S1 / 2)) × a−f ·・ ・ ・ ・ (3) can be obtained easily. Position measurement by linear incremental encoders 210 and 1001
Linear incremental encoder 2 in a one-to-one relationship
This is easily realized by counting the number of output pulses of 10, 1001 by the microcomputer 501 in the control system shown in FIG.

As shown in FIG. 15, if the speed outputs of linear incremental encoders 210 and 1001 or their average values are v229 and v129, respectively, the first traveling body 11 is twice as fast as the second traveling body 301 at a certain moment. Considering that it is velocity, the radius of curvature r
Can be approximately represented by r = (v229 / (v229-v129 / 2)) × af ... (4).

Therefore, the microcomputer 501
In P3303, linear incremental encoder 2
S1 and S2 are calculated from the output pulses of 10, 1001 and S
1, S2, a, f to determine r by the equation (3) and RA
Write to M504 or output from linear incremental encoder 210, 1001 to v22
9, v129 is obtained, r is determined from v229, v129, a, and f by the equation (4), and written in the RAM 504.

As described above, in the first embodiment, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and they are used separately for reading the reflective original 2 and the transparent original 13. The transparent original reading original table 12 for reading the transparent original 13 having the light sources 2 and 14 and the original tables 1 and 12 is installed on the second traveling body 301 for reading the reflective original, and is used for two sub-scanning feedback control. The linear encoders 210, 1001 are installed separately in the vertical direction, and the two linear encoders 210, 1001 are installed.
One of the linear encoders 210 of 001 is a traveling member 301 on which the transparent document reading document table 12 is installed.
In the moving body driving device of the image reading device, the linear encoder 210 is installed at a position substantially equal to the height of the transparent document installation position. Feedback signals based on 210, 1001 and 2
The vertical distance between at least one of the two linear encoders 210 and 1001 and the reflection original reading position, and two linear encoders 210 and 1001.
A microcomputer 501 that constitutes a correction unit that determines a correction value of the output signal of the linear encoder 210 at the time of reading a reflective original from the vertical distance a between 1001.
Since the sub-scanning drive is provided, accurate sub-scanning drive can always be performed, and even when the state of the sub-scanning traveling body 512 that is the sub-scanning control target changes, accurate sub-scanning drive can be performed. In the first embodiment, the original table 12 for reading the transparent original 13 is the first traveling body 1 for reading the reflective original.
1 may be installed, or the linear encoder 210 may be installed on the transparent document reading document table 13.

The second embodiment of the present invention is an embodiment of the invention described in claim 2. In the second embodiment, the original table 1 for reading the transparent original 13 in the first embodiment is used.
2 is installed on the second traveling body 301 for reading the reflective original, and the two linear encoders 210 and 1001 are installed separately in the vertical direction. Two linear encoders 21
One of the 0, 1001 linear encoders 1001 is installed on the first traveling body 11 for reading the reflective original, and the linear encoder 1001 is installed at a height equal to or substantially equal to the height of the reflective original installation position. Another linear encoder 210 is a document table 12 for reading a transparent document,
Alternatively, the traveling body 301 on which the document table 12 is installed
And the linear encoder 210 is installed at a height equal to or substantially equal to the height of the transparent document installation position. Further, since the driven system of the running body using a belt such as a steel belt or a wire is the same as that in FIGS. 2 to 4, the description thereof will be omitted. Further, the control system in the second embodiment is similar to that shown in FIG. 5, and therefore its explanation is omitted.

In the second embodiment, when the guide rails 202 and 203 have a curvature for the reasons explained in FIG. 10 and the like, the movements of the first traveling body 11 and the second traveling body 302 are different. FIG. 16 shows the situation. Generally, guide rails 20
Even if the curvature occurs in 2, 203, it is quite small, so the movement of the traveling bodies 11, 302 is a rotational movement as shown in FIG. 16, but the points on the traveling bodies 11, 302 are approximately It can be regarded as a translational movement.

Therefore, the second traveling member 302 is the second traveling member 302 on which the transparent original reading original table 12 is installed.
At the linear encoder 210 installed at a height equal to or substantially equal to the transparent document installation position of, the radius of curvature r of the guide rails 202, 203 and the guide rail 202,
The radius of curvature is a value obtained by adding the vertical distance h between the 203 and the document table 12 (the second traveling member 301) for reading the transparent document, and the guide rails 202 and 203 are rotated about the center point O of the curvature. it seems to do.

As shown in FIG. 16, the transparent original setting position of the transparent original reading original 12 (or the second traveling member 302) and the reflective original reading position of the reflective original reading original 1 on the first traveling member 11 are set. The vertical gap with the linear encoder 1001 installed at a height equal to or substantially equal to is set to g. v1001 is the speed measurement result of the first traveling body 11 (or the original plate 1 for reading the reflection original) by the linear encoder 1001, and vtrn is the first traveling body 11
Represents a virtual speed obtained by converting the speed of the above into the speed of the second traveling body 11 at the transparent document reading position. This virtual speed v
trn can be obtained by v1001 / 2 and can be expressed as vtrn = ((r + h) / (r + h-g)) × v1001 / 2 ... (5) from FIG. ((R + h) / (r + h-
Since g)) / 2 is a constant that is determined only by the mechanical arrangement of the traveling body drive device, this calculation can be easily realized whether it is performed digitally or analogically.

FIG. 17 shows a control system in the second embodiment when a transparent original is read when the output of the linear encoder 1001 is corrected. Here, the same symbols as those in FIG. 8 represent those having the same function, and therefore the description thereof will be omitted. Information on the speed v1001 (i-1) of the first traveling body 11 detected by the state detection interface device 1002 based on the output signal of the linear encoder 1001 is a constant ((5) given by the above equation (5) in block 2001. (R + h) / (r + h-g)) / 2 is multiplied and converted into the speed vtrn (i-1) of the second traveling body 11 at the position of the transparent document reading original table 12, and calculation is performed via the feedback loop 2002. Given to section 806. After this, the same control calculation as in the first embodiment of FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor.

This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated. All the control calculations including the calculation of the above formula (5) are performed by numerical calculations in the microcomputer 501, and can be easily realized.

FIG. 18 is a flow chart showing the operation flow of this embodiment. When the image reading apparatus starts reading with the start button or the like, it is determined whether or not the prescan mode is set (P3301). P33
If it is determined in 01 that the prescan mode is set, in P3302, the control system for prescan (the control system shown in FIG. 8 when the linear encoder 210 is used, and the control system shown in FIG. 9 when the linear encoder 1001 is used) is displayed. The linear DC motor 801 is driven by the control system shown) to drive the sub-scanning traveling body 512 in the sub-scanning direction. Next, the microcomputer 501 determines the radius of curvature r in P3303 as described above, writes it in the RAM 504, and returns to P3301.

When it is determined in P3301 that the image reading mode is selected instead of the prescan mode, it is determined in P3304 whether the transparent original is read. If it is determined in P3304 that the transparent original is read, in P4305 and P3306, the linear DC motor 801 is driven by the image reading control system shown in FIG. Then, the transparent original 13 is read. When the reading of the transparent original 13 is completed, the image reading operation of the image reading device is completed.

On the other hand, when it is determined in P3304 that the reading of the reflective original is not the reading of the transparent original, the linear DC motor 801 is controlled by the image reading control system shown in FIG. 9 in P4307 and P3308. When driven, the sub-scanning traveling body 512 is driven in the sub-scanning direction, and the reflection original 2
Is read. When the reading of the reflection original 2 is completed, the image reading operation of the image reading device is completed.

The radius of curvature r used in block 2001 in the image reading control system shown in FIG. 17 at the time of reading the transparent original is the value determined in P3303, and the radius of curvature r in the state immediately before reading the transparent original is used. Therefore, even if the state of the sub-scanning traveling body 512 to be controlled changes, accurate sub-scanning control can be performed, and accurate sub-scanning control can always be performed.

As described above, in the second embodiment, the mode for reading the reflective original 2 and the mode for reading the transparent original 13 can be selected, and the reading of the reflective original 2 and the reading of the transparent original 13 are separately performed. Light sources 3, 14 used
And a document table 1 and 12, the transparent document reading document table 12 for reading the transparent document 13 is installed on the first traveling body 11 for reading the reflective document, and two sub-scanning feedback control linear encoders 210 are provided. 1001 are installed vertically apart from each other, and the two linear encoders 21
One of 0, 1001 linear encoder 1001
Is installed on the first traveling body 11 for reading a reflective original, and the linear encoder 1001 is installed at a position equal to or substantially equal to the height of the reflective original installation position. Two linear encoders 210, 1 during prescan of the reading device
From the feedback signal based on 001, the vertical distance between at least one of the two linear encoders 210 and 1001 and the transparent document reading position, and the vertical distance a between the two linear encoders 210 and 1001. Since the microcomputer 501 which constitutes the correction means for determining the correction value of the output signal of the linear encoder 1001 at the time of reading the transparent original is provided, accurate sub-scan drive can always be performed, and the sub-scan of the sub-scan control target can be performed. Even if the state of the traveling body 512 changes, accurate sub-scanning drive can be performed. In addition, the second
In the embodiment, the original table 12 for reading the transparent original 13 may be installed on the first traveling body 11, and the linear encoder 210 may be installed on the transparent original reading original table 13.

FIG. 19 shows a third embodiment of the present invention. The third embodiment is one of the embodiments of the invention described in claim 3 in which a direct drive type linear DC motor is used as a drive source to directly drive the second traveling body. Further, in FIG. 20, in the third embodiment, the second traveling body 301, the linear DC motor, and the second traveling body 301 for reading the reflective original (that is, the original table 12 for reading the transparent original) are installed at an arbitrary height. FIG. 20 is a diagram showing a relative positional relationship between the linear encoder 5101 that is installed and a linear encoder 5111 that is installed at an arbitrary height on the first traveling body 11, and is a view of FIG. 19 viewed from the left side. Figure 1
9 and FIG. 20, those denoted by the same symbols as in FIG. 1 and FIG. 3 have the same functions, and therefore their explanations are omitted. Further, since the driven system of the running body using a belt such as a steel belt or a wire is the same as that of FIG. 4, its description is omitted.

In the third embodiment, the linear encoder 5101 is installed at an arbitrary height on the second traveling body 302 on which the original table 12 for reading transparent originals is installed. Here, a linear encoder movable portion 5101A including a light source and a sensor is attached to the second traveling body 302, and this linear encoder movable portion 5101A includes a linear encoder fixed portion 5101B including a linear scale fixed to the main body 22. Together with this, a so-called optical linear incremental encoder 5101 is formed.

A linear encoder 5111 is installed on the first traveling body 11 at an arbitrary height. here,
Linear encoder moving part 5 including light source and sensor
111A is attached to the first traveling body 11, and this linear encoder movable portion 5111A is combined with a linear encoder fixed portion 5111B including a linear scale fixed to the main body 22 to form a so-called optical linear incremental encoder 5111. is doing.

In such a configuration, the coil 207 of the linear DC motor is controlled by a control system (not shown) based on the output signals of these linear encoders 5101 and 5111.
When a current is applied to the second traveling member 302, on which the original table 12 for reading the transparent original is installed, the second scanning member 302 can be driven in the sub-scanning direction by the direct drive in the direction of A in FIG.

FIG. 21 shows the block configuration of the control system in the third embodiment. In FIG. 21, the same symbols as those in FIG. 5 indicate those having the same functions, and therefore their explanations are omitted. In the third embodiment, the output side of the linear encoder 5101 installed on the second traveling body 301 and the output side of the linear encoder 5111 installed on the first traveling body 11 are respectively interface devices 530 for state detection.
It is connected to the input side of 1,5311. These interface devices 5301 and 5311 are equipped with counters for counting the output pulses of the linear encoders 5101 and 5111, respectively.
Output sides of 1, 5111 are connected to the microcomputer 501 via a bus 505, and feedback control is executed based on a control system described later. A system for detecting the speed of the linear DC motor 511 (sub-scanning traveling body 512), that is, a state detection interface device 5 for processing the output signals of the linear encoders 5101 and 5111.
The processing methods of 301 and 5311 are the same as those in the first embodiment, and therefore their explanations are omitted.

22 and 23 show block configurations of the control system when the output signals of the linear encoders 5101 and 5111 are not corrected in the third embodiment. Here, FIG.
Shows a reading of a transparent original, and FIG. 23 shows a reading of a reflective original. In FIG. 22, the same symbols as those shown in FIG. 8 above indicate the same symbols, and the description thereof will be omitted. Further, in FIG. 23, the same symbols as those shown in FIG. 9 have the same functions, and the explanation thereof will be omitted. In the third embodiment, the control system shown in FIG. 22 is selected and used when reading a transparent original, and the control system shown in FIG. 23 is selected and used when reading a reflective original.

In the control system shown in FIG. 22, the speed v5101 (i-1) of the second traveling body 302 detected by the interface device 5301 for state detection based on the output signal of the linear encoder 5101 at the time of reading the transparent original is used. Information is given to the calculation unit 806 via the feedback loop 6001. Thereafter, the same control calculation as that shown in FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated.

Further, in the control system shown in FIG. 23, the speed v5111 (i-1) of the first traveling body 11 detected by the interface device 5311 for state detection based on the output signal of the linear encoder 5111 at the time of reading the reflection original. The information of 1) is multiplied by a constant (1/2) in block 1201 to be converted into the speed of the second traveling body 302, and is given to the block 806 via the feedback loop 6101. Thereafter, the same control calculation as that shown in FIG. 9 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated. The microcomputer 50 performs all the control calculations including the speed calculation of the second traveling body 302 and the conversion of the speed of the first traveling body 11 to the speed of the second traveling body 302.
Since it is performed by the numerical operation within 1, it can be easily realized.

In the third embodiment, when the guide rails 202 and 203 have a curvature for the reason explained in FIG. 10 and the like, the movements of the first traveling body 11 and the second traveling body 302 are different. FIG. 24 shows the situation. Generally, guide rails 20
Even if a curvature occurs in 2, 203, it is quite small, so the motion of the traveling bodies 11, 302 is a rotational motion as shown in FIG. 24, but each point on the traveling bodies 11, 302 is approximately It can be regarded as a translational movement.

Therefore, the second traveling member 302 is provided with the guide rail 20 at the linear encoder 5101 attached at an arbitrary position of the transparent original reading original table 12.
The radius of curvature r of 2, 203 and the guide rails 202, 20
3 and the linear encoder 5101 vertical distance DD
The value obtained by adding the
It is considered that rotational movement is performed around the center point O of the curvature of 03.

As shown in FIG. 24, the transparent original setting position 12 'of the transparent original reading original 12 (or the second traveling body 302) and the transparent original reading original 12 (or the second traveling body 302). The vertical distance from the linear encoder 5101 installed at an arbitrary height is set to ee, and the transparent document setting position 12 ′ of the transparent document reading document table 12 (or the second traveling member 302) and the first traveling member are set. 1
1 linear encoder 51 installed at any height
The vertical distance from 11 is ff.

V 5101 is the speed measurement result of the second traveling body 301 by the linear encoder 5101, and vtrn 3
Represents the speed of the second traveling body 301 at the transparent document reading position 12 '. This speed vtrn3 is determined by the transparent original reading original 12 (or the second traveling member 3) from FIG.
02) can be expressed as follows: vtrn3 = ((r + DD-ee) / (r + DD)) * v5101 ... ((R + DD-ee) / (r +
DD)) is a constant that is determined only by the mechanical arrangement of the traveling body drive device, and thus this calculation can be easily realized whether it is performed digitally or analogically.

Further, the speed vtrn3 at the transparent original reading position 12 'is v5 at the position of the linear encoder 5111 installed on the first traveling body 11 at an arbitrary position.
24 is obtained, and the vertical distance between the two linear encoders 5101 and 5111 is dd, and the measured speed v51 by the linear encoder 5111 installed at an arbitrary position on the first traveling body 11 is shown in FIG.
11 is used, vtrn3 = ((r + DD-ee) / (r + DD-ee-ff)) * v5111 / 2 = ((r + DD-ee) / (r + DD-dd)) * v5111 / 2 ... (7) Can be expressed as ((R + DD-ee) / (r + D
Since D-dd)) / 2 is a constant determined only by the mechanical arrangement of the traveling body drive device, this calculation can be easily realized whether it is performed digitally or analogically.

It is installed at a reflection document setting position 11 'on the reflection document reading document table 1 (or the first traveling member 11) and at an arbitrary height of the reflection document reading document table 1 (or the first traveling member 11). The vertical gap between the linear encoder 5111 and the linear encoder 5111 is set to gg, and the reflection original setting position 1 of the reflection original reading original table 1 (or the first traveling body 11) is set to gg.
1 ′ and the vertical interval between the linear encoder 5101 installed at an arbitrary height on the second traveling body 301 by hh.
And

From FIG. 24, the virtual speed v obtained by converting the speed of the second traveling member 301 into the speed at the reflection original reading position 11 '.
ref3 is vref3 = ((r + DD-dd-gg) / (r + DD)) * v5101 = ((r + DD-hh) / (r + DD)) * v5101 (8) ((R + DD-hh) / (r +
DD)) is a constant that is determined only by the mechanical arrangement of the traveling body drive device, and thus this calculation can be easily realized whether it is performed digitally or analogically.

A virtual speed vref obtained by converting the speed of the second traveling member 301 into the speed at the reflection original reading position 11 '.
3 has a speed of v5 at the position of the linear encoder 5111.
From the fact that 111/2 is obtained and from FIG.
If the measured speed v5111 by the linear encoder 5111 installed at an arbitrary position on the traveling body 11 is used, vref3 = ((r + DD-dd-gg) / (r + DD-dd)) * v5111 / 2 = ((r + DD-hh ) / (R + DD-dd)) × v5111 / 2 (9) ((R + DD-hh) / (r + D
Since D-dd)) / 2 is a constant determined only by the mechanical arrangement of the traveling body drive device, this calculation can be easily realized whether it is performed digitally or analogically.

FIGS. 25 and 26 show a control system in the third embodiment when a transparent original is read when the outputs of the linear encoders 5101 and 5111 are corrected.
FIG. 25 shows a case where the sub-scanning control is performed based on the output of the linear encoder 5101 attached to the second traveling body 301, and FIG. This is the case where the sub-scanning control is performed. Here, the same symbols as those in FIG. 8 represent those having the same function, and therefore the description thereof will be omitted.

In FIG. 25, the linear encoder 510 is
The speed v5 of the second traveling body 301 detected by the state detection interface device 5301 based on the output signal of No. 1
The information of 101 (i-1) is the constant ((r + DD-ee) / (r given by the above equation (6) in block 5501).
+ DD)) is applied and converted to the speed vtrn3 (i-1) of the second traveling body 301 at the transparent document reading position 12 ', and the calculation unit 806 is performed via the feedback loop 5502.
Given to. After this, the same control calculation as in the first embodiment of FIG. 8 is performed and the control voltage u (i) to the linear DC motor is obtained.
Is required. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning direction.
The above loop is repeated.

Further, in FIG. 26, the speed v5111 (i-) detected by the state detecting interface device 5311 based on the output signal of the linear encoder 5111.
The information of 1) is the constant ((r + DD-ee) / (r + DD-dd)) /
It is multiplied by 2 to be converted into the speed vtrn3 (i-1) of the second traveling body 301 at the transparent document reading position 12 ', and is given to the calculation unit 806 via the feedback loop 5602. After this, the same control calculation as in the first embodiment of FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated. All the control calculations including the calculations of the above formulas (6) and (7) are performed by numerical calculation in the microcomputer 501, and can be easily realized.

FIG. 27 and FIG. 28 show the control system in the third embodiment when the reflection original is read when the outputs of the linear encoders 5101 and 5111 are corrected.
FIG. 27 shows a case where sub-scanning control is performed based on the output of the linear encoder 5101 attached to the second traveling body 301, and FIG. 28 is based on the output of the linear encoder 5111 attached to the first traveling body 11. This is the case where the sub-scanning control is performed. Here, the same symbols as those in FIG. 8 represent those having the same function, and therefore the description thereof will be omitted.

In FIG. 27, the linear encoder 510 is
The speed v5 of the second traveling body 301 detected by the state detection interface device 5301 based on the output signal of No. 1
The information of 101 (i-1) is a constant ((r + DD-hh) / (r given by the above equation (8) in block 5701).
+ DD)) is applied and converted to the speed vref3 (i-1) of the second traveling body 301 at the reflection document reading position 11 ', and the calculation unit 806 is performed via the feedback loop 5702.
Given to. After this, the same control calculation as in the first embodiment of FIG. 8 is performed and the control voltage u (i) to the linear DC motor is obtained.
Is required. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning direction.
The above loop is repeated.

Further, in FIG. 28, the speed v5111 (i-) detected by the state detecting interface device 5311 based on the output signal of the linear encoder 5111.
The information of 1) is the constant ((r + DD-hh) / (r + DD-dd)) /
It is multiplied by 2 to be converted into the speed vref3 (i-1) of the second traveling body 301 at the reflection original reading position 11 ', and is given to the arithmetic unit 806 via the feedback loop 5802. After this, the same control calculation as in the first embodiment of FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated.

All the control operations including the calculations of the above equations (8) and (9) are performed by numerical operations in the microcomputer 501 and can be easily realized. Here, as the control system in the third embodiment, the one shown in FIG. 25 or FIG. 26 is selected and used when the transparent original is read, and the one shown in FIG. 27 or FIG. 28 is selected and used when the reflective original is read.

FIG. 29 is a flow chart showing the operation flow of this embodiment. When the image reading apparatus starts reading with the start button or the like, it is determined whether or not the prescan mode is set (P3301). P33
If it is determined in 01 that the pre-scan mode is set, in P5902, the pre-scan control system (the control system shown in FIG. 22 when the linear encoder 5101 is used, and FIG. 23 when the linear encoder 5111 is used) is displayed. The linear DC motor 801 is driven by the control system shown) to drive the sub-scanning traveling body 512 in the sub-scanning direction. Next, the microcomputer 501 determines the radius of curvature r in P5903 and writes it in the RAM 504, as will be described later.
Return to 301.

When it is determined in P3301 that the image reading mode is selected instead of the prescan mode, it is determined in P3304 whether the transparent original is read. If it is determined in P3304 that the transparent original is read, in P5905 and P3306, the linear DC motor 801 is driven by the image reading control system shown in FIG. The sub-scanning drive is performed and the transparent original 13 is read. When the reading of the transparent original 13 is completed, the image reading operation of the image reading device is completed.

On the other hand, when it is determined in P3304 that the reflective original is not read, but the transparent original is read, in P5907 and P3308, the process shown in FIG.
The linear DC motor 801 is driven by the image reading control system shown in FIG. 8 to drive the sub-scanning traveling body 512 in the sub-scanning direction, and the reflection original 2 is read. When the reading of the reflection original 2 is completed, the image reading operation of the image reading device is completed.

Here, when the transparent original is read, the radius of curvature r used in the block 5501 in the image reading control system shown in FIG. 25, the radius of curvature r used in the block 5601 in the image reading control system shown in FIG. 26, the reflection original. The radius of curvature r used in the block 5701 in the image reading control system shown in FIG. 27 at the time of reading, FIG.
The radius of curvature r used in the block 8601 in the image reading control system shown in is the value determined in P3303. Since the radius of curvature r in the state immediately before reading the original is used, the sub-scanning traveling body 512 to be controlled is Even if the state changes, accurate sub-scanning control can be performed, and accurate sub-scanning control can always be performed.

Next, the method of determining the radius of curvature r in the third embodiment will be described. FIG. 30 shows FIG. 22 or FIG.
The state of the sub-scanning start position and the sub-scanning end position of the sub-scanning traveling body 512 controlled by the control system shown in FIG. In FIG. 30, α is the sub-scanning start position of the sub-scanning traveling body 512, and β is the sub-scanning end position of the sub-scanning traveling body 512. The position outputs of the two linear encoders 5101 and 5111 are shown in FIG.
Since it is inclined by θ as shown in FIG. 5, different values are shown as in S23 and S13.

Considering that the first traveling body 11 travels twice the distance of the second traveling body 301 at the same time, the radius of curvature r is approximately r = (S23 / (S23-S13 / 2)) × dd-DD (10) can be easily obtained. Position measurement by the linear incremental encoders 5101 and 5111 is easily realized by counting the number of output pulses of the linear incremental encoders 5101 and 5111 having a one-to-one relationship with the position by the microcomputer 501 in the control system shown in FIG. To be done.

Further, as shown in FIG. 31, assuming that the speed outputs of linear incremental encoders 5101 and 5111 or their average values are v263 and v163, respectively, the first traveling body 11 and the second traveling body 301 are at the same speed as those of the second traveling body 301 at a certain moment.
Considering that the speed is double, the radius of curvature r can be approximately represented by r = (v263 / (v263-v163 / 2)) × dd-DD ... (11). it can.

Therefore, the microcomputer 501
In P3303, linear incremental encoder 5
From the output pulses of 101, 5111, S263, S163
From S263, S163, dd, DD (10)
R is determined by an equation and written in the RAM 504, or the linear incremental encoders 5101 and 511 are used.
V26 and v163 are calculated from the output pulse of 1
3, v163, dd, DD and the like, r is determined by the equation (11) and written in the RAM 504.

As described above, in the third embodiment, the mode of reading the reflective original 2 and the mode of reading the transparent original 13 can be selected, and the reflective original 2 and the transparent original 13 are read separately. Light sources 3, 14 used
Further, the transparent original reading original table 12 for reading the transparent original 13 having the original tables 1 and 12 is installed on the second traveling body 301 for reading the reflective original, and two sub-scanning feedback control linear encoders 5101 are provided. In the traveling body driving device of the image reading device in which 5111 is vertically separated, in the reflective original reading mode, two linear encoders 51 are used at the time of prescanning of the image reading device.
01 and 5111, the vertical distance between at least one of the two linear encoders 5101 and 5111 and the reflection original reading position, and the two linear encoders 5101 and 511.
The correction value of the output signal of the two linear encoders 5101 and 5111 is determined from the vertical distance between the two and the feedback based on the two linear encoders 5101 and 5111 during the prescan of the image reading apparatus in the transparent original reading mode. From the signal, the vertical distance between at least one of the two linear encoders 5101 and 5111 and the transparent document reading position, and the vertical distance between the two linear encoders 5101 and 5111, the two linear encoders 5101 511
Since the microcomputer 501 which constitutes the correction means for determining the correction value of the output signal of the above is provided, it is possible to always perform accurate sub-scanning drive, and when the state of the sub-scanning traveling body 512 which is the sub-scanning control target changes. However, accurate sub-scan drive can be performed. In the third embodiment, the original table 12 for reading the transparent original 13 may be installed on the first traveling body 11 for reading the reflective original, and the linear encoder 210 is used for the transparent original reading original table 13. It may be installed in.

The fourth embodiment of the present invention is an embodiment of the invention described in claim 4. Since the fourth embodiment is the same as the first embodiment shown in FIGS. 1, 3, 4, 5, 8 and 9, the description thereof will be omitted.
The control system for reading the transparent original in the fourth embodiment is the same as the control system shown in FIG.

In the fourth embodiment, when the guide rails 202 and 203 have a curvature for the reason explained in FIG. 10 and the like, the movements of the first traveling body 11 and the second traveling body 302 are different. FIG. 11 shows the situation. In view of this, in the fourth embodiment, a control system shown in FIG. 32 is used as a control system for reading a reflective original, taking this into consideration. In FIG. 32, the same symbols as those in FIG. 12 indicate the same functions, and the description thereof will be omitted.

In FIG. 32, the linear encoder 210
State detection interface device 5 based on the output signal of
The information of the velocity v210 (i-1) detected by 08 is provided to the block 806 via the feedback loop 811. Further, the target speed information R (i) generated by the command generator 506 is the reciprocal of the constant (r + f)) / ((r
+ F-e) is applied and new target speed information R1
(I) is obtained, and this R1 (i) is given to the calculation unit 806.

Thereafter, the same control calculation as in the first embodiment of FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated. All the control operations including the calculation of the block 2801 are performed by the microcomputer 50.
It can be realized easily by the numerical operation within 1. Here, although the digital PI control method as a control method has been described as an example, the control method is not adversely bite But analog control.

FIG. 33 is a flow chart showing the operation flow of the fourth embodiment. When the image reading apparatus starts reading with the start button or the like, it is determined whether or not the prescan mode is set (P3301). P3
If it is determined in 301 that the prescan mode is set, in P3302, the control system for prescan (the control system shown in FIG. 8 when the linear encoder 210 is used, and the control system shown in FIG. 9 when the linear encoder 10111 is used) is displayed. The linear DC motor 801 is driven by the control system shown) to drive the sub-scanning traveling body 512 in the sub-scanning direction. Next, the microcomputer 501 determines the curvature radius r in P3303 as described in FIGS. 14 and 15, writes it in the RAM 504, and returns to P3301.

If it is determined in P3301 that the image reading mode is selected instead of the prescan mode, it is determined in P3304 whether the transparent original is read. If it is determined in P3304 that the transparent original is read, in P3305 and P3306, the linear DC motor 801 is driven by the image reading control system shown in FIG. Then, the transparent original 13 is read. When the reading of the transparent original 13 is completed, the image reading operation of the image reading device is completed.

On the other hand, if it is determined at P3304 that the reflection original is not read, but the transparent original is read, then the linear DC motor 801 is driven by the image reading control system shown in FIG. 32 at P8807. The sub-scanning traveling body 512 is driven in the sub-scanning direction to read the reflection original 2 (P3308). When the reading of the reflection original 2 is completed, the image reading operation of the image reading device is completed.

Here, the radius of curvature r used in the block 2801 in the image reading control system shown in FIG. 32 at the time of reading the reflection original is the value determined in P3303, and the curvature radius r in the state immediately before the original reading is used. Therefore, even when the state of the sub-scanning traveling body 512 to be controlled changes, accurate sub-scanning control can be performed,
Accurate sub-scanning control can always be performed.

As described above, in the fourth embodiment, the mode for reading the reflective original 2 and the mode for reading the transparent original 13 can be selected, and the reading of the reflective original 2 and the reading of the transparent original 13 are performed separately. Light sources 3, 14 used
Further, the transparent original reading original 12 for reading the transparent original 13 is installed on the second traveling body 301 for reading the reflective original, and has two original encoders 1 and 12, and two sub-scanning feedback control linear encoders 210. 1001 are installed vertically apart from each other, and the two linear encoders 21
0 or 1001 of the linear encoder 210 is installed on the transparent manuscript reading manuscript plate 12 or the traveling body 301 on which the transparent manuscript manuscript manuscript plate 12 is installed, and the installation position of the linear encoder 210 is transparent. In the traveling body driving device of the image reading device which is set at a position equal to or substantially equal to the height of the document setting position, the two linear encoders 21 are used during the prescan of the image reading device.
0 and 1001, a vertical distance between at least one of the two linear encoders 210 and 1001 and the reflection original reading position, and a vertical distance between the two linear encoders 210 and 1001. Since the microcomputer 501 which constitutes the correction means for determining the correction value of the control target value at the time of reading the reflection original is provided, accurate sub-scanning drive can always be performed, and the sub-scanning traveling body 512 to be sub-scanning controlled.
Even if the state of is changed, accurate sub-scanning drive can be performed. In the fourth embodiment, the transparent original 1
The original table 12 for reading 3 may be installed on the first traveling body 11 for reading the reflective original, and the linear encoder 210 may be installed on the transparent original reading original table 13.

The fifth embodiment of the present invention is an embodiment of the invention described in claim 5. The fifth embodiment is the same as the second embodiment shown in FIGS. 1, 3, 4, 5, 8 and 9, and the description thereof will be omitted.
The control system for reading the transparent original in the fifth embodiment is similar to the control system shown in FIG.

In the fifth embodiment, when the guide rails 202 and 203 have a curvature for the reason explained in FIG. FIG. 16 shows the situation. In view of this, in the fifth embodiment, the control system shown in FIG. 34 is used as the control system for reading the transparent original in consideration of this fact. In FIG. 34, the same symbols as those in FIG. 17 indicate the same functions, and the description thereof will be omitted.

In FIG. 34, the linear encoder 100
The information of the speed v1001 (i-1) detected by the state detection interface device 1002 based on the output signal of No. 1 passes through the feedback loop 811 and the calculation unit 806.
Given to. Further, the target speed information R (i) generated by the command generator 506 is the reciprocal of the constant (2 (r + h-
g) / (r + h)) is multiplied to obtain new target speed information R2 (i), and this R2 (i) is calculated by the calculation unit 806.
Given to.

Thereafter, the same control calculation as in the first embodiment shown in FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated. All the control operations including the calculation of block 2901 are performed by the microcomputer 50.
It can be realized easily by the numerical operation within 1. Here, although the digital PI control method as a control method has been described as an example, the control method is not adversely bite But analog control.

FIG. 35 is a flow chart showing the operation flow of the fifth embodiment. When the image reading apparatus starts reading with the start button or the like, it is determined whether or not the prescan mode is set (P3301). P3
If it is determined in 301 that the prescan mode is set, in P3302, the control system for prescan (the control system shown in FIG. 8 when the linear encoder 210 is used, and the control system shown in FIG. 9 when the linear encoder 10111 is used) is displayed. The linear DC motor 801 is driven by the control system shown) to drive the sub-scanning traveling body 512 in the sub-scanning direction. Next, the microcomputer 501 determines the curvature radius r in P3303 as described in FIGS. 14 and 15, writes it in the RAM 504, and returns to P3301.

When it is determined in P3301 that the image reading mode is selected instead of the prescan mode, it is determined in P3304 whether the transparent original is read. If it is determined in P3304 that the transparent original is read, the linear DC motor 801 is set in P9005 by the image reading control system shown in FIG.
Is driven to drive the sub-scanning traveling body 512 in the sub-scanning direction, and the transparent original 13 is read (P3306). When the reading of the transparent original 13 is completed, the image reading operation of the image reading device is completed.

On the other hand, if it is determined in P3304 that the reflective original is read instead of the transparent original, the linear DC motor 801 is driven by the image reading control system shown in FIG. 9 in P4307. The sub-scanning traveling body 512 is driven in the sub-scanning direction, and the reflection original 2 is read (P3308). When the reading of the reflection original 2 is completed, the image reading operation of the image reading device is completed.

Here, the radius of curvature r used in the block 2901 in the image reading control system shown in FIG. 34 at the time of reading the reflection original is the value determined in P3303, and the curvature radius r in the state immediately before reading the original is used. Therefore, even when the state of the sub-scanning traveling body 512 to be controlled changes, accurate sub-scanning control can be performed,
Accurate sub-scanning control can always be performed.

As described above, in the fifth embodiment, the mode for reading the reflective original 2 and the mode for reading the transparent original 13 can be selected, and the reading of the reflective original 1 and the reading of the transparent original 13 are performed separately. Light sources 3, 14 used
Further, the transparent original reading original 12 for reading the transparent original 13 is installed on the second traveling body 301 for reading the reflective original, and has two original encoders 1 and 12, and two sub-scanning feedback control linear encoders 210. 1001 are installed vertically apart from each other, and the two linear encoders 21
One of 0, 1001 linear encoder 1001
Is installed on the first traveling body 11 for reading a reflective original, and the linear encoder 1001 is installed at a position equal to or substantially equal to the height of the reflective original installation position. Two linear encoders 210, 1 during prescan of the reading device
From the feedback signal based on 001, the vertical distance between at least one of the two linear encoders 210 and 1001 and the transparent document reading position, and the vertical distance between the two linear encoders 210 and 1001. Since the microcomputer 501 which constitutes the correction means for determining the correction value of the control target value at the time of reading the original is provided, accurate sub-scanning drive can always be performed, and the state of the sub-scanning traveling body 512 to be the sub-scanning control target. Even if is changed, accurate sub-scanning drive can be performed. In the fifth embodiment, the original table 12 for reading the transparent original 13 is the first for reading the reflective original.
The linear encoder 210 may be installed on the traveling body 11, and the linear encoder 210 may be installed on the transparent document reading original table 13.

The sixth embodiment of the present invention is an embodiment of the invention described in claim 6. The sixth embodiment is the same as the third embodiment described above with reference to FIGS. 4, 19 to 23, and the description thereof will be omitted. In the sixth embodiment, when the guide rails 202 and 203 have a curvature for the reason explained in FIG.
The movement of the traveling body 302 is different. FIG. 24 shows the situation.

In view of this, in the sixth embodiment, the control system shown in FIGS. 36 and 37 is used as the control system for reading the transparent original in consideration of this fact. Figure 3
6 is a case where the sub-scanning control is performed based on the output signal of the linear encoder 5101 attached to the second traveling body 301, and FIG. 37 is the output signal of the linear encoder 5111 attached to the first traveling body 11. This is a case where the sub-scanning control is performed based on 36 and 37,
The same symbols as those in FIGS. 19 and 20 indicate the same functions, and the description thereof will be omitted.

In FIG. 36, the linear encoder 510 is
The information of the speed v5101 (i-1) detected by the state detection interface device 5301 based on the output signal of No. 1 passes through the feedback loop 9201 and the calculation unit 80.
Given to 6. Also, the target speed information R (i) generated by the command generator 506 is the reciprocal of the constant ((r + DD)) given by the above-mentioned equation (6) in block 9202.
/ (R + DD-ee)) is applied to obtain new target speed information R5 (i), and this R5 (i) is calculated by the calculation unit 8
It is given to 06. After this, the same control calculation as in the first embodiment of FIG. 8 is performed and the control voltage u to the linear DC motor is
(I) is required. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated.

Further, in FIG. 37, the speed v5111 (i-) detected by the state detecting interface device 5311 based on the output signal of the linear encoder 5111.
The information of 1) is given to the calculation unit 806 via the feedback loop 9301. Also, the target speed information R (i) generated by the command generator 506 is stored in the block 930.
The reciprocal of the constant (2 (r
+ DD-dd) / (r + DD-ee)) is applied to obtain new target speed information R6 (i).
(I) is given to the calculation unit 806. After this, the same control calculation as in the first embodiment of FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u
(I) is output to the linear DC motor and the sub-scanning traveling body 5 is output.
12 is sub-scanning driven, and the above loop is repeated.

All the control operations including the calculations of the blocks 9202 and 9302 are performed by the numerical operation in the microcomputer 501 and can be easily realized. Here, although the digital PI control method as a control method has been described as an example, the control method is not adversely bite But analog control. 38 and 39 show the control system at the time of reading a reflection original in the control system in the sixth embodiment. FIG. 38 shows a case where sub-scanning control is performed based on the output signal of the linear encoder 5101 attached to the second traveling body 301.
39. As will be apparent from the description below and FIG. 39, FIG.
The case where sub-scanning control is performed based on the output signal of the encoder 5111 is shown. Here, in FIGS. 38 and 39, the same symbols as those in FIGS. 28 and 29 indicate the same functions, and the description thereof will be omitted.

In FIG. 38, the linear encoder 510 is
The information of the speed v5101 (i-1) detected by the state detection interface device 5301 based on the output signal of No. 1 passes through the feedback loop 9401 and the calculation unit 80.
Given to 6. Further, the target speed information R (i) generated by the command generator 506 is the reciprocal of the constant ((r + DD)) given by the above equation (8) in block 9402.
/ (R + DD-hh)) is applied to obtain new target speed information R7 (i), and this R7 (i) is calculated by the calculation unit 8
It is given to 06. After this, the same control calculation as in the first embodiment of FIG. 8 is performed and the control voltage u to the linear DC motor is
(I) is required. This control voltage u (i) is output to the linear DC motor to drive the sub-scanning traveling body 512 in the sub-scanning, and the above loop is repeated.

Further, in FIG. 39, the speed v5111 (i-) detected by the state detecting interface device 5311 based on the output signal of the linear encoder 5111.
The information of 1) is given to the calculation unit 806 via the feedback loop 9501. Further, the target speed information R (i) generated by the command generator 506 is stored in the block 950.
The reciprocal of the constant (2 (r
+ DD-dd) / (r + DD-hh)) is applied to obtain new target speed information R8 (i).
(I) is given to the calculation unit 806. After this, the same control calculation as in the first embodiment of FIG. 8 is performed to obtain the control voltage u (i) for the linear DC motor. This control voltage u
(I) is output to the linear DC motor and the sub-scanning traveling body 5 is output.
12 is sub-scanning driven, and the above loop is repeated.

All the control operations including the calculations in the blocks 9402 and 9502 are performed by numerical operations in the microcomputer 501 and can be easily realized. Here, although the digital PI control method as a control method has been described as an example, the control method is not adversely bite But analog control. In the control system of the sixth embodiment, the one shown in FIG. 36 or FIG. 37 is selected and used at the time of reading a transparent original, and the control system of FIG. 38 or FIG.
The one shown in is selected and used.

FIG. 40 is a flow chart showing the operation flow of the sixth embodiment. When the image reading apparatus starts reading with the start button or the like, it is determined whether or not the prescan mode is set (P3301). P3
If it is determined in 301 that the pre-scan mode is set, in P5902, the control system for pre-scan (the control system shown in FIG. 22 when the linear encoder 5101 is used, and FIG. 23 when the linear encoder 5111 is used) is displayed. The linear DC motor 801 is driven by the control system shown) to drive the sub-scanning traveling body 512 in the sub-scanning direction. Next, the microcomputer 501 determines in P5903 the radius of curvature r as described in FIGS.
Write in 4, and return to P3301.

If it is determined in P3301 that the image is not in the prescan mode but in the image reading mode, it is determined in P3304 whether or not the transparent original is read. If it is determined in P3304 that the transparent original is read, in P9605 the linear DC motor 801 is driven by the image reading control system shown in FIG. 36 or 37, and the sub-scanning traveling body 512 is sub-scanned. The transparent original 13 is driven to be read (P3
306). When the reading of the transparent original 13 is completed, the image reading operation of the image reading device is completed.

On the other hand, when it is determined in P3304 that the reflective original is read instead of the transparent original, the linear DC motor 801 is operated by the image reading control system shown in FIG. 38 or 39 in P9607. Is driven to drive the sub-scanning traveling body 512 in the sub-scanning direction, and the reflection original 2 is read (P3308). Reflective original 2
When the reading of all is finished, the image reading operation of the image reading device is finished.

Here, when the transparent original is read, the radius of curvature r used in the block 9202 in the image reading control system shown in FIG. 36 or the curvature radius r used in the block 9302 in the image reading control system shown in FIG. 37, the reflection original. The radius of curvature r used in the block 9402 in the image reading control system shown in FIG. 38 during reading
Alternatively, the radius of curvature r used in block 9502 in the image reading control system shown in FIG. 39 is the value determined in P3303, and the radius of curvature r in the state immediately before the reading of the original is used. Even if the state of the body 512 changes, accurate sub-scanning control can be performed, and accurate sub-scanning control can always be performed.

As described above, in the sixth embodiment, the mode for reading the reflective original 2 and the mode for reading the transparent original 13 can be selected, and the reading of the reflective original 2 and the reading of the transparent original 13 are performed separately. Light sources 3, 14 used
Also, the transparent original reading original table 12 for reading the transparent original 13 having the original tables 1 and 12 is installed on either one of the second traveling bodies 301 for reading the reflective originals, and is used for two sub-scanning feedback control. Linear encoder 510
In a traveling body driving device of an image reading device in which 1, 5111 are vertically separated from each other, a feedback signal based on two linear encoders 5101 and 5111 and two linear encoders at the time of pre-scanning of the image reading device in a reflective original reading mode. 5101, 5111
The correction value of the control target value is determined from the vertical distance between at least one of the linear encoders and the reflection original reading position and the vertical distance between the two linear encoders 5101 and 5111. A feedback signal based on the two linear encoders 5101 and 5111 at the time of pre-scanning of the image reading device, a vertical distance between at least one of the two linear encoders 5101 and 5111 and a transparent document reading position, and two linear encoders. 510
Since the microcomputer 501 which constitutes the correction means for determining the correction value of the control target value from the vertical distance between the first and the fifth 111 is provided, it is possible to always perform accurate sub-scanning drive, and the sub-scanning control target. Even when the state of the sub-scanning traveling body 512 changes, accurate sub-scanning driving can be performed. In the sixth embodiment, the original table 12 for reading the transparent original 13 is the first for reading the reflective original.
The linear encoder 210 may be installed on the traveling body 11, and the linear encoder 210 may be installed on the transparent document reading original table 13.

[0138]

As described above, according to the first aspect of the present invention, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and the reading of the reflective original and the reading of the transparent original are performed separately. A light source and a document table used for the above, and a transparent document reading document table for reading a transparent document is installed on either one of the first traveling body and the second traveling body for reading the reflective document, and two sub-scans are provided. The feedback control linear encoders are vertically separated from each other, and one of the two linear encoders is the original plate for reading the transparent original, or the traveling body on which the original plate for reading the transparent original is installed. And an image reading apparatus in which the position of the one linear encoder is equal to or almost equal to the height of the position of the transparent original. In the traveling body driving device, a feedback signal based on the two linear encoders at the time of prescanning of the image reading device, a vertical distance between at least one linear encoder of the two linear encoders and a reflection original reading position, and Since the correction means for determining the correction value of the output signal of the linear encoder at the time of reading the reflection original is provided based on the vertical distance between the two linear encoders, accurate sub-scanning drive can always be performed, and the sub-scanning can be performed. Even if the state of the controlled object changes, accurate sub-scanning drive can be performed.

According to the second aspect of the invention, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and the light source and the original used separately for reading the reflective original and reading the transparent original. A transparent original reading original table for reading a transparent original is installed on either the first traveling body or the second traveling body for reading the reflective original, and two sub-scanning feedback control linear encoders are provided. The two linear encoders are installed vertically apart from each other, one linear encoder of the two linear encoders is installed on the first traveling body for reading the reflective original, and the installation position of the one linear encoder is the reflective original installation position. In the traveling body driving device of the image reading device which is located at a position equal to or substantially equal to the height of the When a transparent original is read, based on a feedback signal based on the linear encoder, a vertical distance between at least one of the two linear encoders and a transparent original reading position, and a vertical distance between the two linear encoders. Since the correction means for determining the correction value of the output signal of the linear encoder is provided, accurate sub-scan drive can always be performed, and accurate sub-scan drive can be performed even when the state of the sub-scan control target changes. be able to.

According to the third aspect of the present invention, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and the light source and the original used separately for reading the reflective original and reading the transparent original. A transparent original reading original table for reading a transparent original is installed on either the first traveling body or the second traveling body for reading the reflective original, and two sub-scanning feedback control linear encoders are provided. In a traveling body driving device of an image reading device installed separately in the vertical direction, a feedback signal based on the two linear encoders and a linear signal of at least one of the two linear encoders during prescan of the image reading device in a reflective original reading mode. The vertical distance between the encoder and the reflection original reading position, and the two linear encoders And a vertical distance between the over Da,
A correction value of the output signal of the two linear encoders is determined, and in the transparent original reading mode, a feedback signal based on the two linear encoders at the time of pre-scanning of the image reading device, and at least one of the two linear encoders. Since the correction means for determining the correction value of the output signal of the two linear encoders is provided based on the vertical distance from the transparent original reading position and the vertical distance between the two linear encoders, it is always accurate. Sub-scanning drive can be performed, and accurate sub-scanning drive can be performed even when the state of the sub-scanning control target changes.

According to the fourth aspect of the present invention, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and the light source and the original used separately for reading the reflective original and for reading the transparent original. A transparent original reading original table for reading a transparent original is installed on either the first traveling body or the second traveling body for reading the reflective original, and two sub-scanning feedback control linear encoders are provided. The two linear encoders are vertically separated from each other, and one of the two linear encoders is installed on the transparent manuscript reading manuscript table or a traveling body on which the transparent manuscript reading manuscript manuscript is installed, and The traveling member drive unit of the image reading apparatus is set such that the installation position of the one linear encoder is equal to or substantially equal to the height of the transparent document installation position. In a prescan of the image reading device, a feedback signal based on the two linear encoders, a vertical distance between at least one of the two linear encoders and a reflection original reading position, and a distance between the two linear encoders. Since the correction means for determining the correction value of the control target value at the time of reading the reflective original is provided based on the vertical distance of the reflection original, it is possible to always perform accurate sub-scanning drive, and the state of the sub-scanning control target changes. Even in this case, accurate sub-scanning drive can be performed.

According to the fifth aspect of the present invention, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and the light source and the original used separately for reading the reflective original and reading the transparent original. A transparent original reading original table for reading a transparent original is installed on either the first traveling body or the second traveling body for reading the reflective original, and two sub-scanning feedback control linear encoders are provided. The two linear encoders are installed vertically apart from each other, one linear encoder of the two linear encoders is installed on the first traveling body for reading the reflective original, and the installation position of the one linear encoder is the reflective original installation position. In the traveling body driving device of the image reading device which is located at a position equal to or substantially equal to the height of the When a transparent original is read, based on a feedback signal based on the linear encoder, a vertical distance between at least one of the two linear encoders and a transparent original reading position, and a vertical distance between the two linear encoders. Since the correction means for determining the correction value of the control target value is provided, accurate sub-scanning drive can always be performed, and even when the state of the sub-scanning control target changes, accurate sub-scanning drive can be performed. .

According to the sixth aspect of the present invention, the mode for reading the reflective original and the mode for reading the transparent original can be selected, and the light source and the original used separately for reading the reflective original and reading the transparent original. A transparent original reading original table for reading a transparent original is installed on either the first traveling body or the second traveling body for reading the reflective original, and two sub-scanning feedback control linear encoders are provided. In a traveling body driving device of an image reading device installed separately in the vertical direction, a feedback signal based on the two linear encoders and a linear signal of at least one of the two linear encoders during prescan of the image reading device in a reflective original reading mode. The vertical distance between the encoder and the reflection original reading position, and the two linear encoders And a vertical distance between the over Da,
The correction value of the control target value is determined, and in the transparent original reading mode, the feedback signal based on the two linear encoders at the time of the prescan of the image reading apparatus,
From the vertical distance between at least one of the two linear encoders and the transparent document reading position, and the vertical distance between the two linear encoders,
Since the correction means for determining the correction value of the control target value is provided,
Accurate sub-scanning drive can always be performed, and accurate sub-scanning drive can be performed even when the state of the sub-scanning control target changes.

[Brief description of drawings]

FIG. 1 is a plan view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing an example of an image reading apparatus to which the present invention is applied.

FIG. 3 is a side view showing the first embodiment.

FIG. 4 is a front view showing the belt before the sub scanning starts and after the sub scanning ends in the first embodiment.

FIG. 5 is a block diagram showing a block configuration of a control system in the first embodiment.

FIG. 6 is a timing chart showing the operation timing of the first embodiment.

FIG. 7 is a flowchart showing an interrupt processing flow of the microcomputer in the first embodiment.

FIG. 8 is a linear encoder 21 according to the first embodiment.
FIG. 6 is a block diagram showing a block configuration of a control system when no correction is made using an output of 0.

FIG. 9 is a linear encoder 10 according to the first embodiment.
FIG. 3 is a block diagram showing a block configuration of a control system when no correction is made using the output of 01.

FIG. 10 is a schematic view showing the guide rail of the first embodiment.

FIG. 11 is a diagram showing how the traveling body moves in the first embodiment.

FIG. 12 is a block diagram showing a block configuration of a control system when the output of the linear encoder is corrected in the first embodiment.

FIG. 13 is a flowchart showing an operation flow of the first embodiment.

FIG. 14 is a diagram showing a state of a sub-scanning start position and a sub-scanning end position of the traveling body in the first embodiment.

FIG. 15 is a diagram showing speeds of two traveling bodies in the first embodiment.

FIG. 16 is a diagram showing how the traveling body moves in the control system according to the second embodiment of the present invention.

FIG. 17 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when correcting the output of the linear encoder in the second embodiment.

FIG. 18 is a flowchart showing an operation flow of the second embodiment.

FIG. 19 is a plan view showing a third embodiment of the present invention.

FIG. 20 is a side view showing the third embodiment.

FIG. 21 is a block diagram showing a control system of the third embodiment.

FIG. 22 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when no correction is made using the output of the linear encoder in the third embodiment.

FIG. 23 is a block diagram showing a block configuration of a control system at the time of reading a reflective original in the case where no correction is made using the output of the linear encoder in the third embodiment.

FIG. 24 is a diagram showing how the traveling body moves in the control system of the third embodiment.

FIG. 25 is a linear encoder 51 according to the third embodiment.
3 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when the output of 01 is corrected. FIG.

FIG. 26 is a linear encoder 51 according to the third embodiment.
11 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when correcting the output of FIG.

FIG. 27 is a linear encoder 51 according to the third embodiment.
3 is a block diagram showing a block configuration of a control system at the time of reading a reflective original when correcting the output of 01. FIG.

FIG. 28 is a linear encoder 51 according to the third embodiment.
11 is a block diagram showing a block configuration of a control system at the time of reading a reflective original when correcting the output of FIG.

FIG. 29 is a flowchart showing an operation flow of the third embodiment.

FIG. 30 is a front view showing a state of a sub-scanning start position and a sub-scanning end position of the traveling body in the third embodiment.

FIG. 31 is a diagram showing speeds of two traveling bodies in the third embodiment.

FIG. 32 is a block diagram showing a block configuration of a control system at the time of reading a reflective original when correcting the output of the linear encoder in the fourth embodiment of the present invention.

FIG. 33 is a flow chart showing an operation flow of the fourth embodiment.

FIG. 34 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when correcting the output of the linear encoder in the fifth embodiment of the present invention.

FIG. 35 is a flow chart showing an operation flow of the fifth embodiment.

FIG. 36 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when correcting the output of the linear encoder 5101 in the sixth embodiment of the present invention.

FIG. 37 is a linear encoder 51 according to the sixth embodiment.
11 is a block diagram showing a block configuration of a control system at the time of reading a transparent original when correcting the output of FIG.

FIG. 38 is a linear encoder 51 according to the sixth embodiment.
3 is a block diagram showing a block configuration of a control system at the time of reading a reflective original when correcting the output of 01. FIG.

FIG. 39 is a linear encoder 51 according to the sixth embodiment.
11 is a block diagram showing a block configuration of a control system at the time of reading a reflective original when correcting the output of FIG.

FIG. 40 is a flow chart showing an operation flow of the sixth embodiment.

[Explanation of symbols]

1 Platen for reading reflective originals 2 Reflective original 3 Light source for reading reflective originals 11 First running body 12 Platen for reading transparent originals 13 Transparent manuscript 14 Transparent original reading light source 210 linear encoder 301 Second traveling body 501 microcomputer 511 Linear DC motor 1001 linear encoder

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI H04N 1/107 (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 1/04-1/207 G03B 27/50 G03G 13/04-13/056 G03G 15/04-15/056

Claims (6)

(57) [Claims] 1. A first platen on which a reflective original is placed, and
A first light source for illuminating the reflective original on the first original table;
Note that the reflected light from the reflective original on the first platen is reflected
The photoelectric conversion element that forms an image via the sampling optical system and the
Is supported by an id shaft and moves along the guide shaft,
A first light source and a part of the reflection original reading optical system are stored.
The first traveling body that is held and is driven in the sub-scan at a predetermined speed;
It is supported by a guide shaft and moves along the guide shaft.
Before holding the other part of the reflective original reading optical system
The same speed as the first running body at half the speed of the first running body
The second traveling body driven in the sub-scanning direction and the transparent original are installed.
And the transparent original on the second platen.
A second light source for illuminating and a transparent original on the second original table
Transparency document reading that forms the transmitted light from the image on the photoelectric conversion element
And a second optical system for the second traveling of the second document table.
It is installed on the body and driven by sub-scanning to read and transmit reflective originals.
Running an image reading device that selectively reads documents
In the body driving device, the second document table or the first document table
2 Is the height equal to the height of the transparent document setting position with respect to the running body?
A first linear encoder installed at substantially equal positions,
Installed vertically away from this first linear encoder
The height of the reflection original installation position relative to the first traveling body
A second linear encoder installed at equal or almost equal positions
The coder and the first traveling body are sub-scanning driven at a predetermined speed.
And the second traveling body is half of the first traveling body.
A linear drive that is driven in the sub-scanning direction at the same speed as the first traveling body.
A direct current motor is provided, and the
From the output signal of the linear encoder 1 of the second traveling body
Obtain the speed information, and add this speed information to the guide shaft
Radius of curvature, the guide shaft and the first linear encoder
The vertical distance between the first linear encoder and the front
Vertical spacing between the second document table and the reflection document installation position
Multiply by the constant determined by
Converted to the virtual speed information of the first traveling body, this virtual speed
Based on the difference between the information on the
A traveling body driving device of an image reading device, characterized in that a control voltage value of a computer is obtained. 2. A first platen on which a reflective original is placed, and
A first light source for illuminating the reflective original on the first original table;
Note that the reflected light from the reflective original on the first platen is reflected
The photoelectric conversion element that forms an image via the sampling optical system and the
Is supported by an id shaft and moves along the guide shaft,
A first light source and a part of the reflection original reading optical system are stored.
The first traveling body that is held and is driven in the sub-scan at a predetermined speed;
It is supported by a guide shaft and moves along the guide shaft.
Before holding the other part of the reflective original reading optical system
The same speed as the first running body at half the speed of the first running body
The second traveling body driven in the sub-scanning direction and the transparent original are installed.
And the transparent original on the second platen.
A second light source for illuminating and a transparent original on the second original table
Transparency document reading that forms the transmitted light from the image on the photoelectric conversion element
And a second optical system for the second traveling of the second document table.
It is installed on the body and driven by sub-scanning to read and transmit reflective originals.
Running an image reading device that selectively reads documents
In the body driving device, the second document table or the first document table
2 Is the height equal to the height of the transparent document setting position with respect to the running body?
A first linear encoder installed at substantially equal positions,
Installed vertically away from this first linear encoder
The height of the reflection original installation position relative to the first traveling body
A second linear encoder installed at equal or almost equal positions
The coder and the first traveling body are sub-scanning driven at a predetermined speed.
And the second traveling body is half of the first traveling body.
A linear drive that is driven in the sub-scanning direction at the same speed as the first traveling body.
A direct current motor is provided, and the first
The first traveling body from the output signal of the linear encoder 2
The speed information of the guide shaft is obtained from this speed information.
Radius of curvature of the guide shaft and the second platen or
The vertical distance from the second traveling member and the transparency of the second document table.
Upper and lower sides of the excessive document setting position and the second linear encoder
The second platen is multiplied by a constant determined by the distance in the direction.
Information of the virtual speed of the second traveling body at the transparent original setting position of
Information and convert it based on the difference between this virtual speed information and the target value.
A traveling body driving device of an image reading device, characterized in that the control voltage value u of the linear DC motor is obtained based on the above . 3. A first platen on which a reflective original is placed, and
A first light source for illuminating the reflective original on the first original table;
Note that the reflected light from the reflective original on the first platen is reflected
A photoelectric conversion element to be imaged via an optical system Ri preparative seen, moth
Is supported by an id shaft and moves along the guide shaft,
A first light source and a part of the reflection original reading optical system are stored.
The first traveling body that is held and is driven in the sub-scan at a predetermined speed;
It is supported by a guide shaft and moves along the guide shaft.
Before holding the other part of the reflective original reading optical system
The same speed as the first running body at half the speed of the first running body
The second traveling body driven in the sub-scanning direction and the transparent original are installed.
And the transparent original on the second platen.
A second light source for illuminating and a transparent original on the second original table
Transparency document reading that forms the transmitted light from the image on the photoelectric conversion element
And a second optical system for the second traveling of the second document table.
It is installed on the body and driven by sub-scanning to read and transmit reflective originals.
Running an image reading device that selectively reads documents
In the body driving device, the second document table or the first document table
1st linear installed at an arbitrary height with respect to 2 traveling bodies
Encoder and at any height with respect to the first traveling body
The installed second linear encoder and the first traveling body
The sub-scanning drive at a predetermined speed and the second traveling body.
At the same speed as the first traveling body at half the speed of the first traveling body.
Equipped with a linear DC motor that drives the sub-scan in the same direction,
At the time of scanning the original document, the first linear encoder
Information on the speed of the second traveling body is obtained from the output signal, and
The velocity information includes the radius of curvature of the guide shaft and the guide shaft.
And the vertical distance between the first linear encoder and
The position of the reflection original on the first platen and the first linear
Multiply by a constant determined by the vertical distance from the encoder
And the second run at the position where the reflective document is set on the first platen.
Converted to the speed information of the line body, this speed information and target value
The control voltage value of the linear DC motor based on the difference of
Or the output signal of the second linear encoder
Information of the speed of the first traveling body from the
The information includes the radius of curvature of the guide shaft, the guide shaft and the
The vertical distance from the first linear encoder, the first
And the first linear encoder
Vertical interval with the slider, the first linear encoder
Depending on the vertical distance between the second linear encoder and
Set a reflection original on the first platen by multiplying a fixed constant
Converted to the speed information of the second traveling body at the position,
Based on the difference between the information on the target speed and the target value, the linear
The control voltage value of the flow motor and read the transparent original.
From the output signal of the first linear encoder to the first
2 Obtain the speed information of the traveling body, and add the speed information to the above
Radius of curvature of guide shaft, said guide shaft and said first linear
The vertical distance from the encoder, the first linear encoder
Above and below the coder and the transparent document setting position of the second document table
The second platen is multiplied by a constant determined by the distance in the direction.
Information on the speed of the second traveling body at the transparent document setting position of
Converted, and based on the difference between this speed information and the target value
Obtain the control voltage value of the linear DC motor, or
The first traveling from the output signal of the second linear encoder
Obtain information on the body speed, and use this information to guide
Radius of curvature of the shaft, the guide shaft and the first linear encoder
Distance from the vertical direction, the first linear encoder
In the vertical direction between the transparent document setting position of the second document table and
Interval, the first linear encoder and the second linear encoder
Multiply by a constant determined by the vertical distance from the encoder
The second run at the transparent document setting position of the second document table.
Converted to the speed information of the line body, this speed information and target value
The control voltage value of the linear DC motor based on the difference of
A traveling body driving device for an image reading device, which is characterized in that it is required . 4. A first document table on which a reflective document is placed, and
A first light source for illuminating the reflective original on the first original table;
Note that the reflected light from the reflective original on the first platen is reflected
The photoelectric conversion element that forms an image via the sampling optical system and the
Is supported by an id shaft and moves along the guide shaft,
A first light source and a part of the reflection original reading optical system are stored.
The first traveling body that is held and is driven in the sub-scan at a predetermined speed;
It is supported by a guide shaft and moves along the guide shaft.
Before holding the other part of the reflective original reading optical system
The same speed as the first running body at half the speed of the first running body
The second traveling body driven in the sub-scanning direction and the transparent original are installed.
And the transparent original on the second platen.
A second light source for illuminating and a transparent original on the second original table
Transparency document reading that forms the transmitted light from the image on the photoelectric conversion element
And a second optical system for the second traveling of the second document table.
It is installed on the body and driven by sub-scanning to read and transmit reflective originals.
Running an image reading device that selectively reads documents
In the body driving device, the second document table or the first document table
2 Is the height equal to the height of the transparent document setting position with respect to the running body?
A first linear encoder installed at substantially equal positions,
Installation of away this first Riniae encoder vertically
The height of the reflection original installation position relative to the first traveling body
A second linear encoder installed at equal or almost equal positions
The coder and the first traveling body are sub-scanning driven at a predetermined speed.
And the second traveling body is half of the first traveling body.
A linear drive that is driven in the sub-scanning direction at the same speed as the first traveling body.
A direct current motor is provided, and the
From the output signal of the linear encoder 1 of the second traveling body
Obtain the speed information, and use the guide shaft
Radius of curvature, the guide shaft and the first linear encoder
The vertical distance between the first linear encoder and the front
Vertical spacing between the second document table and the reflection document installation position
Multiply the constant determined by to obtain new target speed information,
This new target speed information and the speed information of the second traveling body.
Control voltage of the linear DC motor based on the difference between
A traveling body driving device of an image reading device, which is characterized by obtaining a value . 5. A first document table on which a reflective document is placed, and
A first light source for illuminating the reflective original on the first original table;
Note that the reflected light from the reflective original on the first platen is reflected
The photoelectric conversion element that forms an image via the sampling optical system and the
Is supported by an id shaft and moves along the guide shaft,
A first light source and a part of the reflection original reading optical system are stored.
The first traveling body that is held and is driven in the sub-scan at a predetermined speed;
It is supported by a guide shaft and moves along the guide shaft.
Before holding the other part of the reflective original reading optical system
The same speed as the first running body at half the speed of the first running body
The second traveling body driven in the sub-scanning direction and the transparent original are installed.
And the transparent original on the second platen.
A second light source for illuminating and a transparent original on the second original table
Transparency document reading that forms the transmitted light from the image on the photoelectric conversion element
And a second optical system for the second traveling of the second document table.
It is installed on the body and driven by sub-scanning to read and transmit reflective originals.
Running an image reading device that selectively reads documents
In the body driving device, the second document table or the first document table
2 Is the height equal to the height of the transparent document setting position with respect to the running body?
A first linear encoder installed at substantially equal positions,
Installed vertically away from this first linear encoder
The height of the reflection original installation position relative to the first traveling body
A second linear encoder installed at equal or almost equal positions
The coder and the first traveling body are sub-scanning driven at a predetermined speed.
And the second traveling body is half of the first traveling body.
A linear drive that is driven in the sub-scanning direction at the same speed as the first traveling body.
A direct current motor is provided, and the first
The first traveling body from the output signal of the linear encoder 2
The speed information of the guide shaft is calculated based on the target speed information.
Radius of curvature of the guide shaft and the second platen or
Vertical distance from the second traveling body, the second document table
Between the transparent original document setting position and the second linear encoder
A new target speed is multiplied by a constant determined by the vertical spacing.
Information on the new target speed and the first
Based on the difference from the speed information of the traveling body, the linear DC
A traveling body drive device of an image reading device, characterized in that a control voltage value of a motor is obtained . 6. A first document table on which a reflective document is placed, and
A first light source for illuminating the reflective original on the first original table;
Note that the reflected light from the reflective original on the first platen is reflected
The photoelectric conversion element that forms an image via the sampling optical system and the
Is supported by an id shaft and moves along the guide shaft,
A first light source and a part of the reflection original reading optical system are stored.
The first traveling body that is held and is driven in the sub-scan at a predetermined speed;
It is supported by a guide shaft and moves along the guide shaft.
Before holding the other part of the reflective original reading optical system
The same speed as the first running body at half the speed of the first running body
The second traveling body driven in the sub-scanning direction and the transparent original are installed.
And the transparent original on the second platen.
A second light source for illuminating and a transparent original on the second original table
Transparency document reading that forms the transmitted light from the image on the photoelectric conversion element
And a second optical system for the second traveling of the second document table.
It is installed on the body and driven by sub-scanning to read and transmit reflective originals.
Running an image reading device that selectively reads documents
In the body driving device, the second document table or the first document table
1st linear installed at an arbitrary height with respect to 2 traveling bodies
Encoder and at any height with respect to the first traveling body
The installed second linear encoder and the first traveling body
The sub-scanning drive at a predetermined speed and the second traveling body.
At the same speed as the first traveling body at half the speed of the first traveling body.
Equipped with a linear DC motor that drives the sub-scan in the same direction,
At the time of scanning the original document, the first linear encoder
The speed information of the second traveling body is obtained from the output signal, and the target
The velocity information includes the radius of curvature of the guide shaft and the guide shaft.
And the vertical distance between the first linear encoder and
The position of the reflection original on the first platen and the first linear
Multiply by a constant determined by the vertical distance from the encoder
Information of the new target speed and the information of this new target speed.
Based on the difference between the information and the speed information of the second traveling body
Obtain the control voltage value of the linear DC motor, or
The first traveling from the output signal of the second linear encoder
Obtain the speed information of the body, and use the guide as the target speed information.
Radius of curvature of the shaft, the guide shaft and the first linear encoder
Vertical distance from the reader, reflection original on the first platen
The installation position and the vertical direction of the first linear encoder
Interval, the first linear encoder and the second linear encoder
Multiply by a constant determined by the vertical distance from the encoder
Information of the new target speed and the information of this new target speed.
Based on the difference between the information and the speed information of the first traveling body
Obtain the control voltage value of the linear DC motor and read the transparent original.
At the time of taking, is it the output signal of the first linear encoder?
To obtain information on the speed of the second traveling body from
The radius of curvature of the guide shaft, the guide shaft and the first
Vertical distance from the linear encoder of the
Near encoder and transparent document setting position of the second document table
A new eye by multiplying by a constant determined by the vertical distance between
This is the information on the target speed, and the information on the new target speed and the
2 Based on the difference from the speed information of the traveling body,
The control voltage value of the flow motor, or
From the output signal of the near encoder, the speed of the first traveling body
Information is obtained, and the curvature half of the guide shaft is added to the target speed information.
Diameter, above the guide shaft and the first linear encoder
Downward distance, the first linear encoder and the second linear encoder
Vertical spacing from the transparent document setting position on the platen
First linear encoder and the second linear encoder
A new eye by multiplying by a constant determined by the vertical distance between
This is the information on the target speed, and the information on the new target speed and the
1 Based on the difference from the speed information of the traveling body,
A drive unit for an image reading apparatus, characterized in that a control voltage value of a flow motor is obtained .