JPH03240358A - Paper carrying type scanner - Google Patents

Abstract

PURPOSE:To prevent deviation at joints of sensors even when the centering accuracy of paper feed rollers is more or less rough by selecting the arrangement interval of zigzag arrangement sensors in the paper feeding direction to be an integral number of multiple of the circumferential length of the paper feed roller. CONSTITUTION:When a manuscript paper 20 is inserted between rollers 4, 8, the paper 20 passes through sensors 12, 14 arranged in front and sensors 16, 18 arranged in rear side of the zigzag arrangement image sensors by the feed roller 4 and is fed to rear side by feed rollers 6, 10 and the information read by sensors 12, 14, 16 and 18 is supplied to a line memory 24 of a controller. The deviation in the timing of an integral number of multiple of the circumference of the roller 4 exists in the sensors arranged in front and rear sides. The deviation is converted into a read line number, a binary line data by the sensors 12, 14 is retarded by the deviation based on the address designation of an address generator 26 and the result is outputted from the memory 24 to an SP (serial-parallel) conversion circuit 28 as serial binary data together with the binary line data from the sensors 16, 18. Thus, the deviation at joints of the sensors is prevented even when the centering accuracy of paper feed rollers is more or less rough.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a paper conveyance type scanner.

[Conventional technology]

In this type of paper-driven scanner, by using a plurality of image sensors shorter than the effective reading width, the problem of increased cost when using a long image sensor is solved. in this case.

It is necessary to arrange a plurality of image sensors in a staggered manner. Conventionally, the distance in the paper feeding direction of the staggered arrangement of image sensors has been set to the minimum distance in order to minimize the memory capacity for delaying read data.

[Problem that the invention seeks to solve]

In this type of scanner, due to the eccentricity of the feed roller,
As shown in FIG. 5, during one rotation of the feed roller 4, the peripheral speed of the feed roller 4 changes in the direction of plus or minus with respect to the reference speed, causing periodic unevenness in paper feeding.

Therefore, even if the sensor reading position deviation is converted into the number of reading lines, and the reading data of the sensor placed in the front row is delayed by the above number of lines by the circuit, these reading data will be on the same line of the manuscript paper. There was a defect in that the read position on the paper of the read data for one line of data that was spliced was shifted in the paper feeding direction due to uneven feeding of the paper.

The present invention aims to eliminate the above-mentioned defects.

[Means to solve problems]

In order to achieve the above object, the present invention feeds paper in a predetermined direction using a paper feed roller connected to a drive device and a presser roller that comes into elastic contact with the paper feed roller, reads this paper with a staggered arrangement sensor, and converts this read binary data into 1 In the apparatus which is connected on a line, the arrangement distance of the staggered sensor in the paper feeding direction is set to be an integral multiple of the circumference of the paper feeding roller.

[Effect]

When the front sensor reads one line on the document paper, this line will next reach the rear sensor when the document paper has moved an integral number of times the circumference of the feed roller, that is, when the feed roller has moved, for example, by one line. This is when the feed roller rotates, and the feed amount of the document sheet during one rotation is constant regardless of changes in the peripheral speed during one rotation of the feed roller. If one revolution of the feed roller is converted into the number of lines read by the sensor, and if the read data of the sensor placed on the front side is delayed by the number of lines read, then the data read by the sensor placed on the rear side and the front side will be The read data of the arranged sensors can be made to coincide with each other on the same line of the original paper in terms of timing.

〔Example〕

The structure of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

In FIG. 3, reference numeral 2 denotes a document reading device, that is, a scanner. At the front and rear of the machine, there are paper feed rollers 4.6 of the same diameter connected to a drive device, and presser rollers 8, 1o that come into elastic contact with the rollers. It is arranged. the roller 4,
Line image sensors 12, 14, 16, and 18 are arranged in a staggered manner as shown in FIG. It is located. Each of the image sensors 12°14.
16.18 is shorter than the effective reading width B of the scanner 2. The front sensors 12, 14 are arranged as shown on the axis Ll perpendicular to the feeding direction of the manuscript paper 20, and the rear sensors 16, 18 are arranged on the axis Ll, which is perpendicular to the feeding direction of the manuscript paper 20.
1 as shown on the axis L2 parallel to the axis L2. The distance G between the axes L1 and L2 is set to an integral multiple of the circumference of the paper feed roller 4. 22 is a paper guide.

Next, the operation of this embodiment will be explained.

When the paper feed rollers 4 and 6 are rotated at a constant speed by the drive device, the circumferential speed of the feed roller 4 changes during one rotation due to eccentric runout, as shown in FIG.

When the manuscript paper 20 is inserted between the rollers 4 and 8, the manuscript paper 20 passes through the front side image sensors 12 and 14 and the rear side image sensors 16 and 18 by the feed roller 4, and is transferred to the feed roller 6 and the presser roller 10. and is sent backwards by said roller 6.10. The image sensor 12 is activated at a predetermined timing based on feedback pulses from an encoder (not shown) generated as the feed roller 4 rotates.
At 14, 16, and 18, the manuscript paper 20 is read line by line. The information read in a line by each of these sensors 12, 14, 16.18 is converted into binary data and supplied to the line memory 24 of the controller. There is a timing difference between the binary line data read by the front sensors 12 and 14 and the binary line data read by the rear sensors 16 and 18, which is an integral multiple of the circumference of the roller 4. This deviation is converted into the number of read lines, and by address specification of the address generator 26, the front sensor 1
2 and 14 read binary lines - the data is delayed by the number of read lines, and the read 2 of the sensors 16 and 18 located on the rear side is read.
Together with the value line data, it is sequentially output from the line memory 24 to the serial-parallel conversion circuit 28 as serial binary data. , two plurality of sensors 12, 14, 16, 1
The serial binary data which is the output of the line memory 24 which is the continuation of the read binary line data of each of the read binary line data of 8 is scanning data on the same line of the manuscript paper 2o, and this data is a single line data that covers the effective reading range. This data is the same as the data obtained by reading one line on a manuscript paper using a long line image sensor. The number of read lines for the timing of the delay corresponds to an integral multiple of the circumferential length of the feed roller 4, as described above. The amount of feed of the original paper per revolution of the feed roller 4 is always constant. Therefore, even if the feeding speed of the document paper 20 fluctuates during one rotation of the feeding roller 4, as shown in FIG.
This does not affect the amount of feed of the original paper 2o in one rotation.

This means that if the distance G between the staggered sensors 12.14 and 16.18 is one time the circumference of the feed roller 4, the same line on the document paper 20 read by the front sensors 12 and 14 will be 4 rotates once, the rear sensor 16,
18 is to read. The reading data of the sensors 12, 14, 16.18 on the same line on the manuscript paper 20 is obtained by delaying the reading data of the front sensors 12, 14 by the number of reading lines corresponding to one revolution of the feed roller 4. This can be continued with the reading data on the same line from the rear sensors 16 and 18. Sensors 12, 14 and 16
．． 18 is not an integral multiple of the circumference of the feed roller 4, the rotation angle of the feed roller corresponding to this distance, that is, the number of lines to be read is not constant. In other words, the feed roller 4 moves until the same line on the document sheet read by the front sensors 12 and 14 reaches the rear sensors 16 and 18.
The rotation angle is not constant and uneven. That is, manuscript paper 2
Even if the document paper 20 is sent in the feeding direction by the set number of readings by the rotation of the feed roller 4 after one line of 0 is read by the front sensors 12 and 14, the number of read lines (that is, the rotation of the feed roller 4) Since there is an unevenness in the feed amount of the manuscript paper 20 relative to the amount), one line read by the front sensor 12.
6 and 18, and the rear sensors 16 and 18 read a position that is different from the line read by the front sensors 16 and 18. . Therefore, the front sensors 12, 14
Even if the read data is delayed by the set number of read lines with respect to the read data of the rear sensors 16 and 18, these read data do not match in timing on the same line of the manuscript paper, and the This results in misalignment of each reading position of the sensor on the document paper.

〔effect〕

Since the present invention is configured as described above, it is not necessary to configure the distance between the sensors as short as possible, and there are also effects such as being able to prevent misalignment at the sensor joint even if the center accuracy of the paper feed roller is somewhat rough.

[Brief explanation of drawings]

1 is an explanatory plan view, FIG. 2 is an explanatory side view, FIG. 3 is an explanatory external view, FIG. 4 is an explanatory block diagram, and FIG. 5 is an explanatory diagram. 2... Scanner, 4, 6 thread feed roller, 8, 1°/press roller, 12, 14, 16. 18... Sensor, 20
...Manuscript paper, 22...Paper guide.

Claims (1)

[Claims] (1) A device that feeds paper in a predetermined direction using a paper feed roller connected to a drive device and a presser roller that comes into elastic contact with the paper, reads this paper with a staggered arrangement sensor, and concatenates the read binary data on one line. A paper conveying type scanner according to the invention, wherein the arrangement distance of the staggered sensor in the paper feeding direction is an integral multiple of the circumferential length of the paper feeding roller.