JP2001163477A - Driving device and driving method for endless belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving device for an endless belt capable of feeding the endless belt with high accuracy. SOLUTION: This endless belt driving device for accurately feeding and driving an endless belt wrapped between a driving roller and a driven roller by a designated amount is provided with an encoder 7 for detecting a rotating angle of the driving roller within a turn, measuring devices 9, 10 for measuring the feed of the endless belt, a storage device 3 for storing the correspondence relationship between the rotating angle within a turn of the driving roller and the feed of the endless belt as a table, and a correcting part 1 for correcting the driving angle of the driving roller corresponding to the target feed of the endless belt according to the angle position of the driving roller at the start of driving the endless belt and the table.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endless belt driving device and a driving method for driving an endless belt for conveying a printing material in a printer or the like with high accuracy.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 4, an endless belt made of stainless steel or the like is wound between a driving roller and another roller to be used as an intermittent feeding belt of a printing material. The following method has been used as a method for correcting an error.

In this method, an intermittent feed amount of an endless belt is measured at every predetermined number of rotations of a driving roller, and if there is an error with a set feed amount, a rotation amount of a motor corresponding to the error is set within an allowable range. The correction is made so that The control for the correction is configured such that the position of the peripheral surface of the drive roller corresponding to the above-described feed error amount is obtained for each of the above-described predetermined rotation speeds, and the control is performed based on the obtained position.

[0004]

However, the above-described conventional feed error correction method has the following problems. (1) Since it is necessary to measure the intermittent feed amount of the endless belt for each predetermined number of rotations of the drive roller, it takes time to perform a measurement operation for calibration. (2) Since it is necessary to cause an error factor to appear periodically at every predetermined number of rotations of the driving roller, the peripheral length of the inner surface of the endless belt is set to be an integral multiple of the outer peripheral length of the driving roller due to the device configuration. This requires a configuration, which reduces the degree of freedom in designing the device. (3) To measure the intermittent feed amount of the endless belt,
High-precision feeding cannot be performed unless the belt feed amount is a multiple of the intermittent feeding pitch used during measurement. (4) A sensor for determining the position of the peripheral surface of the drive roller corresponding to the feed error at every predetermined number of rotations needs to determine a plurality of rotations, which is expensive and time-consuming.

Accordingly, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an endless belt driving device and a driving method capable of feeding an endless belt with high accuracy.

[0006]

Means for Solving the Problems To solve the above-mentioned problems,
In order to achieve the object, an endless belt driving device according to the present invention is an endless belt driving device for precisely feeding and driving a predetermined amount of an endless belt stretched between a driving roller and a driven roller. Detecting means for detecting a rotation angle within one rotation of the drive roller; measuring means for measuring a feed amount of the endless belt; and a rotation angle within one rotation of the drive roller and the endless belt. A storage unit for storing a correspondence relationship of the error of the feed amount as a table, and a target feed amount of the endless belt based on the angular position of the drive roller at the start of driving of the endless belt and the table. Correction means for correcting the drive angle of the corresponding drive roller.

Further, in the endless belt driving device according to the present invention, the storage means stores an error of the feed amount of the endless belt per fixed rotation angle of the driving roller over one rotation of the driving roller. It is characterized by:

Further, in the endless belt driving device according to the present invention, the correction means accumulates an error of the feed amount of the endless belt per the fixed rotation angle up to a target rotation amount of the drive roller, and An error in the total belt feed amount is obtained, and the total rotation amount of the drive roller is corrected based on the error.

In the endless belt driving device according to the present invention, the constant rotation angle is one degree.

The method of driving an endless belt according to the present invention is a method of driving an endless belt for accurately feeding and driving a predetermined amount of an endless belt stretched between a driving roller and a driven roller. A rotation angle within one rotation of the drive roller is detected, and a feed amount of the endless belt corresponding to the detected rotation angle is measured, and a rotation angle within one rotation of the drive roller and a feed amount of the endless belt are measured. A storage step of storing the correspondence of the errors as a table, and the drive roller corresponding to a target feed amount of the endless belt based on the table and the angular position of the drive roller at the start of driving the endless belt. And a correcting step of correcting the drive angle of the above.

Further, in the endless belt driving method according to the present invention, in the storing step, an error in the feed amount of the endless belt per fixed rotation angle of the drive roller is stored over the entire rotation of the drive roller. It is characterized by:

Further, in the endless belt driving method according to the present invention, in the correcting step, an error in the feed amount of the endless belt per fixed rotation angle is accumulated up to a target rotation amount of the drive roller, and the endless belt is driven. An error in the total belt feed amount is obtained, and the total rotation amount of the drive roller is corrected based on the error.

[0013] In the endless belt driving method according to the present invention, the constant rotation angle is 1 degree.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described. Before that, an outline of the present invention will be described.

According to the present invention, an endless belt made of stainless steel or the like is stretched between a driving roller and another roller.
In an apparatus used as an intermittent feed belt for a printing medium, a detector such as an absolute encoder capable of detecting an absolute position of one rotation of the driving roller is used to feed the rotation of the driving roller according to the rotation angle of the driving roller during one rotation of the driving roller. The amount is measured to obtain calibration data, and when the belt is driven, the target feed amount is corrected based on the rotation angle information of the driving roller at the time of starting the driving and the calibration data.

Here, a detector such as an absolute encoder capable of detecting a rotation angle position of one rotation is attached to the drive roller so that the angular position of the drive roller can be detected.

The measurement of calibration data required for high-precision feeding is performed, for example, by rotating 360 degrees around the drive roller n.
It is divided and the drive roller is driven every (360 / n) degrees. The feed amount of the endless belt at this time is measured and stored as a table corresponding to the angle of the drive roller. The belt feed amount may be measured using a laser measuring machine or the like, or a camera and an image processing device may be used if the belt feed amount per operation is small.

For example, when the driving roller diameter is 230φ and the number of divisions n is 360, the theoretical feed amount when the driving roller is driven once is 0.15 m of the belt thickness.
As m, ((230 + 0.15) × π ÷ 360) ≒ 2.0084
mm.

However, when the actual feed amount is measured by operating the drive motor by an angle at which the drive roller is actually driven once, the angle (degree) feed amount (mm) 0 2.0078 1 2.0025 2 2 .0113: 360 2.0039 will be measured.

The reason for this is that the outer diameter of the drive roller is not exactly 230 mm, the roller cannot be processed into a perfect circle, and the drive angle is converted into a pulse number equivalent to 1 degree to drive the NC. This is due to the occurrence of an error or a digit loss accompanying the conversion.

This data and the theoretical feed amount 2.
A data table for calibration is created by obtaining a difference of 0084 mm. This table is as follows: Angle (degree) Feed amount error per degree at that angle (mm) 0-0.00061 + 0.00592-0.0029: 360 + 0.0045

Based on this table, the driving angle of the driving roller is corrected at the time of driving the belt by the following method, and high-precision feeding is performed.

In theory, the endless belt is, for example, 9
In order to feed at a pitch of 5.00 mm, assuming that the thickness of the belt is 0.15 mm, the diameter of the driving roller is 230φ, so that ((230 + 0.15) × π ÷ 360) × 95.00 =
47.30044 degrees It suffices to drive the drive roller.

However, in practice, the outer diameter of the driving roller is 230
mm, the roller cannot be processed into a perfect circle, and so on. Even if the drive roller is rotated by the above angle, the endless belt has
It is sent with a variation of about 0 μm.

Therefore, in order to realize high-precision feeding, it is necessary to add correction data corresponding to the rotational position of the drive roller to the angle of the theoretical value.

The calculation of the correction data is performed as follows.

First, the angle of the drive roller at the start of driving is detected by a detector such as an absolute encoder capable of detecting the absolute angular position of one rotation. This angular position is defined as X degrees.

Next, it is determined in advance how many times the movement pitch of 95.00 mm corresponds to the rotation angle of the drive roller. In this case, it corresponds to 47.30044 degrees. Next, from the position of the drive roller at the present time, in order to determine how much a feed error occurs due to the pitch feed, the amount of the error in the section from X degrees to X + 47 degrees is obtained from the calibration data table. Obtain by the following procedure.

The feed amount data corresponding to X degrees is obtained from the calibration table. Then, the data of the feed amount corresponding to the next X + 1 degrees, the data of the feed amount corresponding to X + 2 degrees, the data of the feed amount corresponding to X + 3 degrees,..., X + 4
Data of a feed amount corresponding to 7 degrees is sequentially added. In this way, when the driving roller is rotated from X degrees to X + 47 degrees, it is possible to determine how much a cumulative error has occurred with respect to the theoretical value and the belt is actually fed.

Based on this data, the accumulated amount of feed error generated by driving the drive roller by a predetermined angle from the current angle can be known.

The rotation angle of the corresponding drive roller is obtained from the accumulated amount of the feed error thus obtained, and the data is used to correct the target drive angle of the drive roller. Become.

Next, an embodiment of the present invention will be specifically described.

FIG. 1 is a block diagram of an endless belt feeder according to an embodiment of the present invention. In the figure, 1 is a CPU, 2 is a ROM, 3 is a RAM, 4 is an NC controller, 5 is a motor, 6 is an encoder interface, 7 is an absolute encoder, 8 is an RS interface, 9 is an image processing device, 10 is an ITV camera. It is.

Next, the operation of the above configuration will be described. The CPU 1 operates according to a program stored in the ROM 2. The contents of the program are described according to the algorithm of the correction method described above. R
AM3 is used for temporarily storing data required for executing the program. The NC controller 4 uses C
The motor 5 is driven to a predetermined angular position according to the data generated by PU1. Encoder interface 6
Converts the data of the absolute encoder 7 so that the CPU 1 can handle the data. RS interface 8
Is used to capture RS data output from the image processing device 9. The image processing device 9 is used for processing image data captured by the ITV camera 10 and extracting position information.

In this configuration, a procedure for creating position correction data for realizing high-accuracy feeding accuracy will be congratulated. Here, the number of divisions for creating correction data is 360 divisions (in 1-degree increments), and the drive roller diameter is φ23.
0, the case where the thickness of the endless belt is 0.15 mm will be described as an example.

The image processing device 9 is configured to process the surface state of the endless belt 13 captured by the ITV camera 10 by a density correlation process. With this processing device, the movement position of the endless belt 13 in the belt feeding direction can be read.

The CPU 1 fetches the angular position information of the encoder 7 via the encoder interface 6 and stores the information on the RAM 3 as angle information for a correction table.

Next, the CPU 1 issues a command to the NC controller 4 to drive the drive roller 11 once at an angle to drive the endless belt 13. At this time, the amount of movement of the drive roller 11 per one degree of the belt is processed by the image processing device 9, and data of the amount of movement is taken in by the CPU 1 via the RS interface 8. This data is stored in CPU1
Are used as data for creating a correction table,
Remember.

In this example, the above procedure is performed for all of the 360 degrees, which is the number of divisions, and the original data of the correction data is collected.

Next, a correction data table is created according to the algorithm described above. The procedure is 360, which is the number of divisions.
And the theoretical feed amount when the drive roller is driven once, (((230+
The difference of 0.15) × π) ÷ 360) ≒ 2.0084 mm is calculated, and the following table corresponding to the angle information of the encoder 7 is created.

Angle (degree) Main error per degree at the angle (mm) 0-0.0006 1 + 0.0059 2-0.0029: 46 + 0.0021 47-0.0031 360 + 0.0045 Based on this, the driving angle of the driving roller is corrected at the time of driving the belt to realize high-precision feeding.

FIGS. 2 and 3 are mechanical configuration diagrams of an endless belt feeder according to an embodiment of the present invention.

In the figure, 5 is a motor for driving the driving roller, 7 is an absolute encoder for detecting the angular position of the driving roller, 11 is a driving roller for driving the belt, and 12 is a belt for stretching the belt. The driven roller 13 is an endless belt for transporting the printing material.

In this configuration, the endless belt 13
Will be described as an example. The angular position of the drive roller 11 at the start of driving is measured by the encoder 7 and is taken into the CPU 1 via the encoder interface 6. The data taken here is 1
If it is, the CPU 1 refers to the correction data in the following procedure and generates drive data for high-accuracy feeding.

First, the angle of the driving roller at the start of driving is 1 degree as described above. Next, it is determined how many times the movement pitch of 95.00 mm corresponds to the angle of the drive roller in terms of angle.

The calculation formula is ((230 + 0.15) × π ÷ 360) × 95.00, which is equivalent to 47.30044 degrees.

Next, from the current position of the driving roller,
In order to determine how much a feed error occurs due to the pitch feed, the following procedure is used to determine how much error occurs in the section from X degrees (here, 1 degree) to X + 47 degrees from the calibration data table.

From the calibration table, data of the feed amount corresponding to one degree is obtained. Then, to this data, data from a table corresponding to the next two degrees, data corresponding to three degrees, data corresponding to four degrees,..., Data of a section up to an angle corresponding to 48 degrees are added. Thus, 1
When the drive roller is rotated from 48 degrees to 48 degrees, it is possible to determine how much a cumulative error has occurred with respect to the theoretical value and the belt is actually fed.

If the data of the accumulated amount of the feed error generated by driving the drive roller by a predetermined angle from the current angle is +0.0257 mm, the rotation angle of the drive roller is corrected by the following procedure. The quantity can be determined.

The theoretical feed amount when the drive roller is driven once is ((230 + 0.15) × π ÷ 360) ≒ 2.0008
From this value, 0.0257 mm is converted to the angle of the drive roller to determine how many times the angle corresponds to 0.00257 ÷ 2.0084 = 0.0012796 degrees.

The theoretical endless belt feed amount is ((230 + 0.15) × π ÷ 360) × 95.00 =
Since this angle is 47.30044 degrees, the correction amount 0.001279 is added to this angle.
47.30044 degrees plus 6 degrees + 0.0012796
By driving the driving roller 11 by 47.301719 degrees, the endless belt 13 can be accurately adjusted by 9 degrees.
It can send 5.000 mm.

The CPU 1 performs the above-described calculations internally, and sends the obtained corrected feed angle information to the NC controller 4.
To the endless belt 13
Will be sent with high accuracy.

As described above, according to the above-described embodiment, in an apparatus in which an endless belt made of stainless steel or the like is stretched between a driving roller and another roller to be used as an intermittent feeding belt of a printing material, Using a detector such as an absolute encoder that can detect the position of one rotation of the roller, for a period of one rotation of the drive roller, measure the feed amount according to the rotation angle of the drive roller to obtain calibration data, and The following effects can be obtained by correcting the target feed amount based on the rotation angle information and calibration data of the drive roller at the time of starting driving at the time of driving, thereby enabling high-precision feeding. is there. (1) Since the intermittent feed of the endless belt only needs to be measured for one rotation of the drive roller, the time for the measurement work for calibration can be reduced. (2) Since it is not necessary to cause an error factor to appear periodically at every predetermined number of rotations of the drive roller, the peripheral length of the inner surface of the endless belt is set to be an integral multiple of the outer peripheral length of the drive roller in terms of the device configuration. This eliminates the necessity to perform the operation, and increases the degree of freedom in designing the apparatus. (3) Since the accuracy of one rotation of the drive roller is measured, the feed amount of the belt need not be a multiple of the intermittent feed pitch used in the measurement, and the feed amount of the belt can be freely changed. (4) Since the sensor for determining the angular position of the drive roller corresponding to the feed error only needs to determine the position of one rotation of the drive roller, an inexpensive rotary encoder or the like can be used.

[0054]

As described above, according to the present invention,
The endless belt can be sent with high accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram of an endless belt driving device according to an embodiment of the present invention.

FIG. 2 is a front view of the transfer device according to the embodiment of the present invention.

FIG. 3 is a side view of the transfer device according to the embodiment of the present invention.

FIG. 4 is a front view of a transfer device according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CPU 2 ROM 3 RAM 4 NC controller 5 Motor 6 Encoder interface 7 Absolute encoder 8 RS interface 9 Image processing device 10 Camera 11 Drive roller 12 Follower roller 13 Endless belt 14 Camera

Claims (8)

[Claims] An endless belt driving device for accurately feeding and driving a predetermined amount of an endless belt stretched between a driving roller and a driven roller, wherein a rotation angle within one rotation of the driving roller is detected. Detecting means for measuring the feed amount of the endless belt; and storing a correspondence relationship between a rotation angle within one rotation of the drive roller and an error of the feed amount of the endless belt as a table. Storage means for storing, and a correction means for correcting a drive angle of the drive roller corresponding to a target feed amount of the endless belt based on the angular position of the drive roller at the start of driving of the endless belt and the table. A drive device for an endless belt, comprising: 2. The apparatus according to claim 1, wherein the storage unit stores an error of a feed amount of the endless belt per a certain rotation angle of the drive roller over one rotation of the drive roller. Endless belt drive. 3. The correction means accumulates an error of the feed amount of the endless belt per the constant rotation angle up to a target rotation amount of the drive roller to obtain an error of a total feed amount of the endless belt. 3. The endless belt driving device according to claim 2, wherein a total rotation amount of the driving roller is corrected based on the error. 4. The endless belt driving device according to claim 2, wherein the constant rotation angle is 1 degree. 5. A method of driving an endless belt for accurately feeding and driving a predetermined amount of an endless belt stretched between a driving roller and a driven roller, wherein a rotation angle within one rotation of the driving roller is detected. At the same time, the feed amount of the endless belt corresponding to the detected rotation angle is measured, and the correspondence between the rotation angle within one rotation of the drive roller and the error of the feed amount of the endless belt is stored as a table. A storage step, and a correction step of correcting a drive angle of the drive roller corresponding to a target feed amount of the endless belt based on the angular position of the drive roller at the start of driving of the endless belt and the table. A method of driving an endless belt. 6. The method according to claim 5, wherein in the storing step, an error in the feed amount of the endless belt per fixed rotation angle of the drive roller is stored over one full rotation of the drive roller. Endless belt drive method. 7. In the correcting step, an error in the feed amount of the endless belt per fixed rotation angle is accumulated up to a target rotation amount of the driving roller to obtain an error in a total feed amount of the endless belt. 7. The apparatus according to claim 6, wherein a total rotation amount of the driving roller is corrected based on the error.
3. The method of driving an endless belt according to item 1. 8. The method according to claim 6, wherein the constant rotation angle is one degree.