JPH09219986A - Running body control unit for image reading device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a running body control unit which can control the speed of a running body without speed deviating from the target speed. SOLUTION: This unit is constituted so that the first running body and the second running body may be driven in a sub-scanning direction at a speed ratio of 2:1 1 by a linear motor 31, the speed of the second running body may be detected by a linear encoder and an interface for detecting a condition, and the speed of the second running body may be controlled based on the detected value. The ratio of the average of the speed of the second running body which is pre-determined to the target speed of the second running body is set to a correction factor Vcorrec. The correction factor Vcorrec is multiplied to the detected speed V (i-1) of the linear motor 31 by a corrector 51, and the speed data of the second running body which is fed back to a computing unit 53 is corrected. The second running body is controlled without any speed deviation based on a different (e)(i) between the moving speed data and a target control value R (i), thus it is possible to conduct drive without any magnification error.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling body control unit of an image reading apparatus for controlling the movement of a traveling body driven in the sub-scanning direction in the image reading apparatus.

[0002]

2. Description of the Related Art In an image reading apparatus of an image forming apparatus such as a copying machine, a running body holding a scanning optical element is run to read a document image. It is possible to control traveling as little as possible,
This is necessary in order to perform highly accurate image reading without a magnification error.

First, an image reading apparatus to which the present invention is applied will be described with reference to FIGS. 14 to 20. FIG.
4 is an explanatory view showing the configuration of the optical system of the image reading apparatus, FIG.
14 is an explanatory diagram showing the configuration of the first traveling body portion and the second traveling body portion of FIG. 14, FIG. 16 is an explanatory diagram showing the configuration of the second traveling body portion of FIG. 15, and FIG. 17 is the pulley of FIG. 18 is an explanatory view showing the structure of the belt portion, FIG. 18 is a block diagram of a control device of the image reading apparatus, FIG. 19 is a signal waveform diagram showing the operation of the state detecting interface of FIG. 18, and FIG. 20 is a state detecting interface of FIG. 5 is a flowchart showing an interrupt operation of the above.

As shown in FIG. 14, the contact glass 1
The original 10 placed on the original is illuminated by the halogen lamp 2, and the reflected light from the original 10 is reflected by the first mirror 3, the second mirror 4, and the third mirror 5 and focused by the lens 6, An image is formed on the CCD sensor 7.

In this case, the first traveling body 8 provided with the first mirror 3 and the halogen lamp 2 and the second traveling body 9 provided with the second mirror 4 and the third mirror 5 are in a ratio of 2: 1. The entire area of the original 10 is read by scanning and moving in the sub-scanning direction at a speed ratio, and the CCD sensor 7 self-scanning in the main scanning direction.

As shown in FIG. 15, the bearing portions 23A and 23B on one end side of the first traveling body 8 are slidably fitted to the first guide shaft 25, and the bearing portion 23C on the other end side is It is slidably fitted to the second guide shaft 26. The bearing portions 24A, 24B on one end side of the second traveling body 9 are slidably fitted to the first guide shaft 25, and the bearing portion 24 on the other end side.
C and 24D are slidably fitted to the second guide shaft 26.

A drive coil 28 is attached to the lower surface of the second traveling body 9 via a movable back yoke 27 for forming a magnetic circuit and a coil substrate (not shown).
A magnet 29 having S poles and N poles alternately arranged in the sub-scanning direction on the surface is disposed in the main body via a back yoke 27B for forming a magnetic circuit while maintaining a constant air gap.

A movable part 9A having a light source and a sensor is attached to the second traveling body 9, and a fixed part 9B having a linear scale is provided on the main body. The movable part 9A and the fixed part 9B are provided. Thus, a linear encoder 30 which is an optical linear incremental encoder is configured. Then, based on the output signal of the linear encoder 30, a current is passed through the coil 28, and the second traveling body 9 is drive-controlled in the sub-scanning direction.

In this case, the bearing portion 24A of the second traveling body 9
The pulleys 21A to 21D are fixed to the outsides of the pulleys 24D to 24D, respectively, and the belt B is placed between the pulleys 21A and 21B.
1, a belt B2 is stretched between the pulleys 21C and 21D. Since the belts B1 and B2 have the same structure, the belt B1 will be described with reference to FIG. 17. One end of the belt B1 is fixed to the main body by a belt end E1, and the belt B1 is wound around the pulleys 21A and 21B half a turn. , The other end of the belt B1 is the belt end E2
It is fixed to the main body by. At a predetermined position, the first traveling body 8 is fixed to the belt B1, which is an intermediate portion between the pulleys 21A and 21B, by the clamp 22A.
The first traveling body 8 is fixed to the belt B2 in the middle portion of C and 214D by the clamp 22B at a predetermined position.

With such a configuration, the first traveling body 8 and the second traveling body 9 are sub-scanned at a speed of 2: 1 and the first traveling body 8 and the second traveling body 9 are sub-scanned.
Since the traveling body 8 travels twice as long as the second traveling body 9, when the reading size is determined, the second traveling body 9 is driven by a distance ½ of the reading size.

The control device for controlling the drive of the traveling body is shown in FIG.
8, the microprocessor 34, ROM3
5, a state instruction generator 37 for instructing a target speed of the linear motor 31 for driving the second traveling body 9 via a bus B to a microcomputer 33 for controlling the overall operation, and a drive signal. A drive interface 38 for outputting is connected, a drive device 39 is connected to the drive interface 38, and a linear motor 31 for driving the second traveling body 9 is connected to the drive device 39.

The linear encoder 30 for detecting the rotation speed of the linear motor 31 is provided with a counter for counting output pulses, and a state detection interface 32 for processing the output of the linear encoder 30 is connected to the linear encoder 30. The interface 32 is connected to the microcomputer 33 via the bus B.

In the control device having such a configuration, the speed of the linear motor 31 is detected by the linear encoder 30 and the state detecting interface 32, and is taken into the microcomputer 33, and the microcomputer 33.
From the target speed input from the state command generation device 37 and the speed of the linear motor 31 input from the state detection interface 32, a command signal is supplied to the drive interface device 38. Based on the drive signal issued from the drive device 39,
The linear motor 31 is rotationally driven.

In this case, in FIG. 19, the counter of the state detecting interface 32 is the linear encoder 30.
20 is executed based on the CLK signal, the decrement count is executed from the given count value, and when the edge e is input to the interrupt terminal of the microprocessor 34, the interrupt routine of FIG. 20 is executed. That is, the decrement count value of the counter of the state detection interface 32 is latched in the internal register of the state detection interface 32 in step S1, and the latched decrement count value is stored in the RAM 36 in step S2. Then, in step S3, the count initial value is set in order to count the pulse period of Tn, the decrement count is started again, and the interrupt process is ended. When the edge e is input to the interrupt terminal again, steps S1 to S3
Is repeated.

Here, the velocity V (i) at the pulse period Tn
Is given by the following equation, where CLK cycle is Tclk, Ne is the number of encoder divisions per unit angle, CLK count is n, and a unit conversion constant to speed is k.

V (i) = k / (Tclk · Ne · n) (1)

Regarding the traveling body control unit of the conventional image forming apparatus for controlling the traveling body based on the calculation in (1),
This will be described with reference to FIGS. 21 and 22. FIG. 21 is a block diagram showing the configuration of a speed control system of a traveling body control unit of a conventional image forming apparatus, and FIG. 22 is a characteristic diagram of traveling body speed controlled by FIG.

The speed signal V (i-1) of the linear motor 31 detected by the equation (1) by the linear encoder 30 and the state detecting interface 32 is input to the arithmetic unit 41 via the feedback loop 46, and the state is calculated. A difference value signal e (i) from the target value signal R (i) from the command generator 37 is calculated.

This difference value signal e (i) is integrated by an integrator 42, multiplied by a constant K1 by a multiplier 43, and an arithmetic unit 44.
Is input to On the other hand, the difference value signal e (i)
Is multiplied by a constant KP and input to the calculation unit 44. Then, in the calculation unit 44, the input from the multiplier 43 and the input from the multiplier 45 are added to calculate the input voltage signal U (i) to the linear motor 31, and the input voltage signal U (i) is calculated.
(I) is input to the linear motor 31, and the linear motor 31 is drive-controlled.

[0020]

When the average speed is slower than the target speed, the speed of the second traveling body 9 whose movement is controlled by the linear motor 31 driven and controlled in this way is 22 (a), and when the average speed is faster than the target speed, it becomes as shown in FIG. In this case, the deviation of the average speed from the target speed is caused by the load of the traveling body and the error of the control system.If this speed deviation exists, the actual average speed can be matched with the target speed. However, it causes a magnification error of the image reading apparatus.

The present invention has been made in view of the current state of traveling body control of an image reading apparatus as described above, and an object thereof is to perform speed control of a traveling body without a speed deviation from a target speed. A possible object is to provide a traveling body control unit of an image reading apparatus.

[0022]

In order to achieve the above object, the invention according to claim 1 has a first traveling body and a second traveling body which respectively hold scanning optical elements, and the first traveling body. A driving means for driving the body and the second traveling body in the sub-scanning direction at a speed ratio of 2: 1; and a speed detecting means for detecting the moving speed of the second traveling body. A traveling body control unit of an image reading device for controlling the moving speed of the second traveling body to a preset sub-scanning speed based on the detection value of the detecting means, and the traveling body control unit of the second traveling body obtained in advance. Feedback control means for controlling the moving speed of the second traveling body by correcting the speed data to be fed back by using the ratio of the average value of the traveling speed and the target speed of the second traveling body as a correction coefficient. It is characterized by having.

[0023] Similarly, in order to achieve the above object, the invention according to claim 2 is the first invention for holding a scanning optical element.
Driving means for driving the first traveling body and the second traveling body in the sub-scanning direction at a speed ratio of 2: 1, and the second traveling body. Of the image reading device for controlling the moving speed of the second traveling body to a preset sub-scanning speed on the basis of the detection value of the speed detecting means. A body control unit, which corrects target speed data by using a ratio of a predetermined moving speed average value of the moving speed of the second traveling body and a target speed of the second traveling body as a correction coefficient. Therefore, the control means for controlling the moving speed of the second traveling body is provided.

Similarly, in order to achieve the above object, the invention according to claim 3 is different from the invention according to claim 1 in that the moving speed of the second traveling body in a plurality of reading sizes in the sub-scanning direction. Is provided in the ROM, and the feedback control unit reads the correction coefficient to correct the speed data to be fed back. It is characterized by that.

Similarly, in order to achieve the above object, the invention according to claim 4 is different from the invention according to claim 2 in that the moving speed of the second traveling body in a plurality of reading sizes in the sub-scanning direction. Is provided in the ROM, and the control unit reads the correction coefficient and corrects the target speed data. It is a feature.

Similarly, in order to achieve the above-mentioned object, the invention according to claim 5 is different from the invention according to claim 3 or 4 in that a correction coefficient acquisition means for acquiring the correction coefficient at the time of prescan is provided. It is characterized by being provided.

Similarly, in order to achieve the above object, the invention according to claim 6 is different from the invention according to claim 5 in that a designation means for designating a reading start position and a reading end position, and designation of the designation means. And a drive unit for driving the correction coefficient acquisition unit.

Similarly, in order to achieve the above-mentioned object, the invention according to claim 7 is different from the invention according to claim 1 or 2 in that the image is read according to the reading size at the time of prescanning of the image forming apparatus. An average value acquisition means for acquiring an average value of the moving speed of the second traveling body is provided.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] A first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a main part of the present embodiment.

In the present embodiment, as shown in FIG. 1, in addition to the conventional speed control system already described with reference to FIG. 21, the linear encoder 3 is provided in the feedback loop 46.
0 and the velocity detection signal V (i-1) of the linear motor 31 detected by the state detection interface 32, the velocity correction coefficient V
A corrector 51 that multiplies correc is provided, and the corrector 51 uses the feedback loop 52 to calculate the calculation unit 53.
It is connected to the. Then, the calculator 53 has a function of calculating a difference value e (i) between the control target value signal R (i) and the speed signal V (i-1) multiplied by the speed correction coefficient Vcorrec. Other parts of the configuration of the present embodiment are the same as those of the conventional image reading apparatus already described with reference to FIGS. 14 to 18.

In the present embodiment, in the arithmetic unit 53,
Control target value signal R (i) from state designation generator 37
And a difference value signal e (i) between the speed signal Vcorrec · V (i−1) multiplied by the speed correction coefficient Vcorrec is calculated, and the difference value signal e (i) is integrated by the integrator 42, The multiplier 43 multiplies the constant K1 and inputs the result to the arithmetic unit 44. On the other hand, the difference value signal e (i) is multiplied by the constant KP in the multiplier 45 and input to the arithmetic unit 44. Then, in the calculation unit 44, the input from the multiplier 43 and the input from the multiplier 45 are added to calculate the input voltage signal U (i) to the linear motor 31, and the input voltage signal U (i) is calculated.
(I) is input to the linear motor 31, and the linear motor 31 is drive-controlled.

Velocity correction coefficient V used in this embodiment
correc is a coefficient for correcting the difference between the target speed and the average value of the actual speeds, and the traveling of the second traveling body 9 is controlled in advance to obtain the average value of the actual speeds. To the target speed of the scanner optical system Vmean / Vre
It is set by calculating f. In the present embodiment, including the speed detection calculation by the above-mentioned expression (1),
The control calculation of the speed control system of
Is calculated numerically.

As described above, according to this embodiment, the average value of the moving speed of the second traveling body 9 is obtained in advance, and the ratio of this average value and the target speed of the second traveling body is used as the correction coefficient. The speed signal V (i
Since -1) is corrected, control without speed deviation is possible, and control of the traveling body of the image reading apparatus is performed without causing a magnification error.

[Second Embodiment] A second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the main part of this embodiment.

In the present embodiment, as shown in FIG. 2, the control target value signal R from the state command generator 37 is added to the conventional speed control system already described with reference to FIG.
(I) is provided with a corrector 55 that multiplies the speed correction coefficient 1 / Vcorrec, and the arithmetic unit 56 calculates the speed correction coefficient 1
Control target value signal R (i) multiplied by / Vcorrec
And a speed signal V (i-1), a difference value e (i) is calculated. Other parts of the configuration of the present embodiment are the same as those of the conventional image reading apparatus already described with reference to FIGS. 14 to 18.

In the present embodiment, in the arithmetic unit 55,
The control target value signal (1 / Vcorre) from the state designation generator 37 multiplied by the speed correction coefficient 1 / Vcorrec
c) .R (i) and the difference value signal e (i) between the speed signal V (i-1) are calculated, and this difference value signal e (i) is integrated by the integrator 42 and the multiplier 43 Is multiplied by a constant K1 and input to the calculation unit 44. On the other hand, the difference value signal e (i) is multiplied by the constant KP in the multiplier 45 and input to the arithmetic unit 44.

Then, in the calculation section 44, the input from the multiplier 43 and the input from the multiplier 45 are added to calculate the input voltage signal U (i) to the linear motor 31, and the input voltage signal U (i) is calculated. U (i) is input to the linear motor 31, and the linear motor 31 is drive-controlled.

Velocity correction coefficient 1 used in this embodiment
/ Vcorrec is a coefficient for correcting the difference between the target speed and the average value of the actual speeds, and the traveling control of the second traveling body 9 is performed in advance to obtain the average value of the actual speeds. Value / the target speed of the scanner optical system 1 / (Vmea
It is set by calculating n / Vref). In the present embodiment, the control calculation of the speed control system of FIG. 1 including the speed detection calculation by the above-mentioned equation (1) is numerically calculated by the microcomputer 33.

As described above, according to the present embodiment, the average value of the moving speed of the second traveling body 9 is obtained in advance, and the ratio of this average value and the target speed of the second traveling body is used as the correction coefficient. Since the target speed is corrected, control without speed deviation is possible, and the control of the traveling body of the image reading apparatus is performed without causing a magnification error.

[Third Embodiment] A third embodiment of the present invention will be described with reference to FIGS. FIG. 3 is an explanatory diagram of a table provided in the ROM of this embodiment,
FIG. 4 is an explanatory diagram of the relationship between the reading size and the speed of the traveling body in the present embodiment, and FIG. 5 is a flowchart showing the operation of the present embodiment.

This embodiment is basically the same as that shown in FIG.
The second embodiment has the same configuration as that of the first embodiment described above, and particularly in the present embodiment, the speed correction corresponding to various reading sizes is previously stored in the ROM 35 of the control device described with reference to FIG. Coefficients Vcorrec1, Vcorrec
2, Vcorrec3 are stored as a table as shown in FIG. Although the average speed of the second traveling body 9 is smaller than the target speed Vref in FIG. 4, the average speeds corresponding to the read size 1, read size 2, and read size 3 are Vmean1 respectively. , V
It takes a value different from mean2 and Vmean3. Corresponding to this, Vcorrect stored in the table
1, Vcorrect2 and Vcorrect3 are respectively Vmean1 / Vref, Vmean2 / Vref,
It corresponds to Vmean3 / Vref.

The configuration of the other parts of this embodiment is the same as that of the first embodiment already described.

The operation of this embodiment will be described with reference to the flowchart of FIG. In this embodiment, when the operator inputs the reading size of the document image such as A4, A3, B4, B5 in step S11, step S12 is performed.
3, the speed correction coefficient Vcor corresponding to the input size is read from the table shown in FIG. 3 stored in the ROM 35.
rec is read and written in the RAM 36, the process proceeds to step S13, the second traveling body 9 is travel-controlled by the speed control system shown in FIG. 1, and the image reading operation is performed in step S14. Done.

As described above, according to the present embodiment, the average value of the moving speed of the second traveling body 9 for various reading sizes is obtained in advance, and the average value and the second traveling body 9 are obtained.
Is stored in the ROM 35 as a speed correction coefficient Vcorrec, and the corresponding speed correction coefficient Vcorrec is automatically read by the operator's input of the reading size and fed back. The signal V (i-1) is corrected, and it is possible to quickly respond to various reading sizes and control without speed deviation can be performed, and the traveling body of the image reading apparatus can be controlled without causing a magnification error. .

[Fourth Embodiment] A fourth embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG. 6 is an explanatory diagram of a table provided in the ROM of this embodiment,
FIG. 7 is a flow chart showing the operation of this embodiment.

This embodiment is basically the same as that shown in FIG.
The third embodiment has the same configuration as that of the second embodiment described above, and particularly in the present embodiment, the speed correction corresponding to various reading sizes is previously stored in the ROM 35 of the control device described with reference to FIG. Coefficients 1 / Vcorrec1, 1 / Vco
rrec2, 1 / Vcorrec3 ... Are stored as a table as shown in FIG.

The configuration of the other parts of this embodiment is the same as that of the second embodiment already described.

The operation of this embodiment will be described with reference to the flowchart of FIG. In the present embodiment, when the operator inputs the reading size of the original image such as A4, A3, B4, B5 in step S21, step S22 is performed.
6, the speed correction coefficient 1 / Vc corresponding to the input size is read from the table shown in FIG. 6 stored in the ROM 35.
orrec is read and written in the RAM 36, and the process proceeds to step S23, in which the traveling of the second traveling body 9 is controlled by the speed control system shown in FIG.
Then, the image reading operation is performed.

As described above, according to the present embodiment, the average values of the moving speeds of the second traveling body 9 for various reading sizes are obtained in advance, and these average values and the target speed of the second traveling body 9 are calculated. Is stored in the ROM 35 as the speed correction coefficient 1 / Vcorrec, and the corresponding speed correction coefficient Vcorrec is automatically read by the operator's input of the reading size, and the control target value R (i) is corrected. In this way, it is possible to quickly respond to various reading sizes and control without speed deviation can be performed, and the traveling body of the image reading apparatus can be controlled without causing a magnification error.

[Fifth Embodiment] A fifth embodiment of the present invention will be described with reference to FIGS. FIG.
Is a block diagram showing a configuration of a main part of the present embodiment, FIG. 9 is a flowchart showing an operation of the present embodiment, and FIG. 10 is a flowchart showing a prescan operation of the present embodiment.

This embodiment basically has the same configuration as that of the third embodiment already described, and particularly, in this embodiment, the correction coefficient acquisition for acquiring the speed correction coefficient during the prescan is performed. A means, a designation means for designating the reading start position and the reading end position, and a correction coefficient acquisition means for driving the correction coefficient acquisition means by the designation of the designation means are provided.

The configuration of the other parts of this embodiment is the same as that of the third embodiment already described.

The present embodiment will be described with reference to the flowchart of FIG. In the present embodiment, similarly to the third embodiment, the average speed (Vmean) corresponding to various reading sizes (size 1, size 2, size 3 ...) In advance.
1, Vmean2, Vmean3 ...) are stored in the ROM 35 as a table shown in FIG.

When the operator inputs the size of the document to be read such as A4 and A3, or the reading start position and the reading end position in step S31, the process proceeds to step S32, and it is determined whether the reading size exists in the table of the ROM 35. If the determination is made and the determination in step S32 is YES, the process proceeds to step S33, and the speed correction coefficient corresponding to the read size is read from the table of the ROM 35. Then, in step S34, the traveling of the second traveling body 9 is controlled by the speed control system shown in FIG.
In step S35, an image reading operation is performed.

On the other hand, if the decision in step S32 is NO, the process advances to step S36, the sub-scan drive is performed by the speed control system during pre-scan shown in FIG. 8, the average speed Vmean is calculated, and step S37. Then, the speed correction coefficient is obtained from the ratio of the average speed Vmean and the target speed Vref. Then, the process proceeds to step S34, the traveling of the second traveling body 9 is controlled by the speed control system shown in FIG. 1, and the image reading operation is performed in step S35.

During this pre-scan, it is determined in step S41 in FIG. 10 whether or not the traveling body has reached the reading start position. If the determination in step S41 is YES, the process proceeds to step S42 to turn ON / OFF. The circuit 57 is turned on, the speed of the linear motor 31 is integrated by the integrator 58, it is determined in step S43 whether the traveling body has reached the reading end position, and the determination in step S43 is YE.
If it is S, in step S44, the ON-OFF circuit 57
Is turned off, and the sub-scanning drive ends. Then, when the pre-scan ends, the average speed Vmean is calculated from the integrated value, and the average speed Vmean corresponding to the read size is calculated.
Is obtained.

As described above, in this embodiment, when the speed correction coefficient for correcting the speed signal V (i-1) of the linear motor 31 to be fed back is stored in the table of the ROM 35, the speed correction coefficient is stored. If the correction is performed and is not stored in the table of the ROM 35, the speed correction coefficient necessary for the pre-scan is calculated, and the calculated speed correction coefficient is used for correction, so that it corresponds to all reading sizes. Thus, the speed correction coefficient can be set accurately and efficiently, and control without speed deviation can be performed, and the traveling body of the image reading apparatus can be controlled without causing a magnification error.

[Sixth Embodiment] A sixth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a flow chart showing the operation of this embodiment.

This embodiment basically has the same configuration as that of the above-described fourth embodiment. Particularly, in this embodiment, the correction coefficient acquisition for acquiring the speed correction coefficient during the prescan is performed. A means, a designation means for designating the reading start position and the reading end position, and a correction coefficient acquisition means for driving the correction coefficient acquisition means by the designation of the designation means are provided.

The configuration of the other parts of this embodiment is the same as that of the fourth embodiment already described.

This embodiment will be described with reference to the flowchart of FIG. Steps S51 to S53 and Steps S55 to S5 of FIG.
The process of 7 is performed in steps S31 to S33 and step S3 of the flowchart of FIG. 9 described above.
Since it is the same as the processing of 5 to step S37,
No duplicate explanation will be given.

In the present embodiment, the traveling of the second traveling body 9 is controlled in step S54 by the speed control system shown in FIG. The other operations of this embodiment are the same as those of the fifth embodiment already described.

As described above, in this embodiment, the speed correction coefficient for correcting the control target value signal R (I) is the ROM 35.
If the table is stored in the table No., the speed correction coefficient is used for correction, and if not stored in the table of the ROM 35, the speed correction coefficient necessary for the prescan is calculated, and the calculated speed correction coefficient is calculated. Since the correction is performed by, the speed correction coefficient can be set accurately and efficiently for all reading sizes, and control without speed deviation becomes possible. It is performed so that no error is generated.

[Seventh Embodiment] A seventh embodiment of the present invention will be described with reference to FIG. FIG. 12 is a flow chart showing the operation of this embodiment.

In the present embodiment, in comparison with the first embodiment already described, the average value of the average values of the moving speeds of the second traveling bodies according to the reading size is acquired during the prescan of the image forming apparatus. Value acquisition means is provided.

The configuration of the other parts of this embodiment is the same as that of the first embodiment already described.

The operation of this embodiment will be described with reference to the flowchart of FIG. When the operator inputs the reading size such as A4, or the reading start position and the reading end position in step S61, the process proceeds to step S62, and the sub-scanning drive is performed by the speed control system during pre-scan shown in FIG. That is, the average speed Vmean is calculated, the process proceeds to step S63, and the speed correction coefficient is obtained from the ratio between the average speed Vmean and the target speed Vref.
Then, in step S64, the traveling control of the second traveling body 9 is performed by the speed control system shown in FIG. 1, and in step S65, the image reading operation is performed.

The other operations of this embodiment are the same as those of the first embodiment already described.

As described above, according to the present embodiment, during the prescan of the image reading apparatus, the average value of the moving speed of the second traveling body 9 according to the read size is obtained, and the average value and the second value are obtained. The speed signal V (i-1) of the fed-back linear motor 31 is corrected by using the ratio with the target speed of the traveling body 9 as a speed correction coefficient, so that various reading sizes can be quickly responded to and control without speed deviation is performed. Therefore, the traveling body of the image reading apparatus is controlled so as not to cause a magnification error.

[Eighth Embodiment] An eighth embodiment of the present invention will be described with reference to FIG. FIG. 13 is a flow chart showing the operation of this embodiment.

In the present embodiment, in comparison with the second embodiment already described, the average value of the average value of the moving speeds of the second traveling bodies according to the reading size is acquired during the prescan of the image forming apparatus. Value acquisition means is provided.

The configuration of the other parts of this embodiment is the same as that of the second embodiment already described.

The operation of this embodiment will be described with reference to the flowchart of FIG. Steps S71 to S73 and step S of the flowchart of FIG.
The processing of 75 is the same as the processing of steps S61 to S63 and step S65 of FIG. 12, respectively, and therefore a duplicate description will not be given.

In the present embodiment, in step S74, the traveling of the second traveling body 9 is controlled by the speed control system shown in FIG. The other operations of this embodiment are the same as those of the seventh embodiment already described.

As described above, according to the present embodiment, during the prescan of the image reading apparatus, the average value of the moving speed of the second traveling body 9 according to the reading size is obtained, and the average value and the second value are obtained. The control target value signal R (i) is corrected using the ratio to the target speed of the traveling body 9 as a speed correction coefficient, which enables quick response to various reading sizes and control without speed deviation. The traveling body is controlled so as not to generate a magnification error.

Although the control by the PI control system has been described in each of the embodiments, the present invention is not limited to each of the embodiments, and P control, I control, PID control, or modern control theory is used. It is also possible to use control or the like.

[0077]

According to the first aspect of the present invention, the first traveling body and the second traveling body, which respectively hold the scanning optical elements, are driven by the driving means in the sub-scanning direction at a speed ratio of 2: 1. It is driven, the moving speed of the second traveling body is detected by the speed detecting means, and the moving speed of the second traveling body is controlled to a preset sub-scanning speed based on the detection value of the speed detecting means. In the traveling body control unit of the image reading apparatus, the feedback control means feeds back the ratio of the average value of the moving speed of the second traveling body obtained in advance and the target speed of the second traveling body as a correction coefficient. Since the moving speed data of the second traveling body is corrected, it is possible to control the second traveling body without velocity deviation and to perform driving without magnification error.

According to the second aspect of the present invention, the driving means drives the first traveling body and the second traveling body, which respectively hold the scanning optical elements, in the sub-scanning direction at a speed ratio of 2: 1. An image reading in which the moving speed of the second traveling body is detected by the speed detecting means, and the moving speed of the second traveling body is controlled to a preset sub-scanning speed based on the detection value of the speed detecting means. In the traveling body control unit of the apparatus, the target speed data is corrected by the control means by using the ratio of the average value of the moving speed of the second traveling body obtained in advance and the target speed of the second traveling body as a correction coefficient. Therefore, it is possible to control the second traveling body without a velocity deviation and to perform driving without a magnification error.

According to the invention of claim 3, in addition to the effect obtained by the invention of claim 1, an average value of the moving speed of the second traveling body in a plurality of reading sizes in the sub-scanning direction,
A table of the correction coefficient of the ratio value data with respect to the target speed of the second traveling body is provided in the ROM, and the feedback control means reads the correction coefficient from the table and corrects the speed data to be fed back. Corresponding to the above, it becomes possible to perform control without speed deviation on the second traveling body, and drive with no magnification error.

According to the invention of claim 4, in addition to the effect obtained by the invention of claim 2, an average value of the moving speed of the second traveling body in a plurality of reading sizes in the sub-scanning direction,
A table for the correction coefficient of the ratio value data with the target speed of the second traveling body is provided in the ROM, and the feedback control means reads the correction coefficient from the table and corrects the target speed data. Correspondingly, it becomes possible to perform control without speed deviation on the second traveling body and drive without magnification error.

According to the invention of claim 5, in addition to the effect obtained by the invention of claim 3 or 4, correction coefficient acquisition means for acquiring a correction coefficient at the time of prescan is provided, so various The speed data that is appropriately and efficiently fed back to the reading size of the target speed data or the target speed data is corrected, and the second traveling body is controlled without a speed deviation, and the driving is performed without a magnification error. It is possible to make it.

According to the invention of claim 6, in addition to the effect obtained by the invention of claim 5, a designating means for designating the reading start position and the reading end position is provided, and the correction coefficient is designated by the designating means. Since the acquisition means is driven, processing for non-specified reading size can be performed quickly and accurately,
By correcting the speed data to be fed back or the target speed data, it becomes possible to perform control without speed deviation on the second traveling body and drive with no magnification error.

According to the invention of claim 7, in addition to the effect obtained by the invention of claim 1 or 2, the movement of the second traveling body in accordance with the reading size at the time of prescanning of the image forming apparatus. Since the average value acquisition means for acquiring the average value of the speed is provided, the speed data to be fed back or the target speed data is corrected with high accuracy even if the image reading device changes with time, and the second traveling is performed. It is possible to control the body without velocity deviation and drive without magnification error.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of a main part of a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a main part of a second embodiment of the present invention.

FIG. 3 is an explanatory diagram of a table provided in a ROM according to a third embodiment of this invention.

FIG. 4 is an explanatory diagram of a relationship between a reading size and a speed of a traveling body according to the same embodiment.

FIG. 5 is a flowchart showing an operation of the same embodiment.

FIG. 6 is an explanatory diagram of a table provided in a ROM according to a fourth embodiment of this invention.

FIG. 7 is a flowchart showing an operation of the embodiment.

FIG. 8 is a block diagram showing a configuration of a main part of a fifth embodiment of the present invention.

FIG. 9 is a flowchart showing an operation of the embodiment.

FIG. 10 is a flowchart showing a prescan operation of the same embodiment.

FIG. 11 is a flowchart showing an operation of the sixth exemplary embodiment of the present invention.

FIG. 12 is a flowchart showing an operation of the seventh embodiment of the present invention.

FIG. 13 is a flowchart showing the operation of the eighth embodiment of the present invention.

FIG. 14 is an explanatory diagram showing a configuration of an optical system of the image reading apparatus.

FIG. 15 is an explanatory diagram showing a configuration of a first traveling body and a second traveling body portion of FIG.

16 is an explanatory diagram showing a configuration of a second traveling body portion of FIG.

FIG. 17 is an explanatory diagram showing a configuration of a pulley and a belt portion of FIG.

FIG. 18 is a block diagram of a control device of the image reading device.

FIG. 19 is a signal waveform diagram showing an operation of the state detection interface of FIG.

20 is a flowchart showing an interrupt operation of the state detection interface of FIG.

FIG. 21 is a block diagram showing a configuration of a speed control system of a traveling body control unit of a conventional image forming apparatus.

22 is a speed characteristic diagram of the traveling body controlled by FIG. 21. FIG.

[Explanation of symbols]

 31 linear motor 42 integrator 43 multiplier 44 arithmetic unit 45 multiplier 51 corrector 55 corrector 56 arithmetic unit 57 ON-OFF circuit 58 integrator

Claims (7)

[Claims] 1. A first traveling body and a second traveling body each holding a scanning optical element, and the first traveling body and the second traveling body are sub-scanned at a speed ratio of 2: 1. Direction driving means and speed detecting means for detecting the moving speed of the second traveling body. Based on the detection value of the speed detecting means, the moving speed of the second traveling body is A traveling body control unit of an image reading device for controlling to a preset sub-scanning speed, wherein a ratio between an average value of the moving speeds of the second traveling body obtained in advance and a target speed of the second traveling body is calculated. A traveling body control unit for an image reading apparatus, comprising feedback control means for controlling the moving speed of the second traveling body by correcting speed data to be fed back as a correction coefficient. 2. A first traveling body and a second traveling body each holding a scanning optical element, and the first traveling body and the second traveling body are sub-scanned at a speed ratio of 2: 1. Direction driving means and speed detecting means for detecting the moving speed of the second traveling body, and based on the detection value of the speed detecting means, the moving speed of the second traveling body is A traveling body control unit of an image reading device for controlling to a preset sub-scanning speed. A traveling body control unit for an image reading apparatus, comprising: a control unit that controls the moving speed of the second traveling body by correcting target speed data as a correction coefficient. 3. The traveling body control unit of the image reading apparatus according to claim 1, wherein an average value of moving speeds of the second traveling body in a plurality of reading sizes in the sub-scanning direction and the second traveling speed are used.
An image reading apparatus characterized in that a table of correction coefficients of ratio value data with respect to the target speed of the traveling body is provided in the ROM, and the feedback control means reads the correction coefficient and corrects the speed data to be fed back. Vehicle body control unit. 4. The traveling body control unit of the image reading apparatus according to claim 2, wherein an average value of moving speeds of the second traveling body in a plurality of reading sizes in the sub-scanning direction and the second traveling speed are used.
The table of the correction coefficient of the ratio value data with respect to the target speed of the traveling body is provided in the ROM, and the control unit reads the correction coefficient to correct the target speed data. Body control unit. 5. The traveling body control unit of the image forming apparatus according to claim 3 or 4, further comprising a correction coefficient acquisition unit that acquires the correction coefficient during pre-scanning. The traveling body control unit of the image reading device. 6. A traveling body control unit of the image forming apparatus according to claim 5, wherein a designation unit that designates a reading start position and a reading end position, and the correction coefficient acquisition unit is driven by the designation of the designation unit. And a driving means for driving the traveling body control unit of the image reading apparatus. 7. The traveling body control unit of the image forming apparatus according to claim 1, wherein the moving speed of the second traveling body according to the reading size is set at the time of prescanning of the image forming apparatus. A traveling body control unit of an image reading apparatus, characterized in that an average value acquisition means for acquiring an average value is provided.