JP2005045468A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of detecting the size of transfer paper fed from a paper feed cassette at a low cost without newly providing a CCD (charge coupled device) system by providing an optical path from a light source to a reader at an arbitrary position on a transfer paper conveyance path from feeding of the transfer paper to writing of an image. <P>SOLUTION: The image forming apparatus can write information, generated by reading reflected light of an image obtained by irradiating a document with the light emitted by a light source by a charge coupled device 3 etc., through a 1st optical path composed of a mirror 4, a lens 5, etc., and converting the reflected light into an electric signal, after data processing, in the transfer paper. In this image forming apparatus, a 2nd light source 20 is provided at the arbitrary position on the transfer paper conveyance path from the feeding of the transfer paper P to the writing of the image, and information generated by guiding external shape information on the transfer paper P crossing the light during transfer paper conveyance, taking in a CCD 3 etc., through a 2nd optical path composed of a mirror 21, a lens 22, etc., and converting it into an electric signal is obtained. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus in which information obtained by taking an image into a CCD (charge coupled device) or the like and converting it into an electrical signal is subjected to data processing and written on a transfer sheet.
[0002]
[Prior art]
In a paper cassette that sets and feeds transfer paper, when setting transfer paper of any size, it is necessary to set the paper size and orientation using a dial or button provided in advance so that the image forming apparatus can recognize it. is there. In addition, it is necessary to input the dimensions of the transfer paper with a numeric keypad for transfer paper that is not of the size standard.
[0003]
[Problems to be solved by the invention]
However, if these settings do not match the actually set size and direction, there is a problem that the written image is shifted from the transfer paper or the transfer paper conveyance control cannot be performed.
Although it is possible to provide a sensor that automatically detects the size and orientation of the transfer paper, it is generally only compatible with limited sizes. In order to detect it, it is necessary to use a large number of sensors and high-performance sensors, which increases the cost and is difficult to commercialize.
In general image forming apparatuses, there is no means for detecting the outer shape or surface state of transfer paper set in a paper feed cassette, and even if transfer paper with poor quality such as tearing, wrinkles, and dirt is fed The image forming process is executed, causing a problem such as a jam during conveyance or a transfer not being performed normally.
A means for providing a CCD system or the like in the transport path and monitoring the quality of the transfer paper increases the cost and is difficult to commercialize.
[0004]
In a general image forming apparatus, transfer paper fed from a paper feed cassette is secured to an appropriate position for image writing to some extent by a position correction mechanism such as a fence, a guide plate, and a registration roller.
However, if the writing start position deviation or transfer paper skew has occurred, there is no means for detecting the transfer paper conveyance state, and normal image forming processing is executed. In some cases, writing to an appropriate position is not possible.
In the case where a CCD device or the like is provided in the transport path and a data processing system is provided to additionally provide a means for monitoring the transport state of the transfer paper, the cost increases and it is difficult to commercialize the product.
Information such as the size, surface state, and transport state of the transfer paper fed and transported to the CCD in the reader can be captured, so there is no need to install a new CCD device or data processing system. The cost of the light source provided on the path and the cost of the optical path to the CCD in the reading device are increased.
Accordingly, an object of the present invention is to provide an optical path to a light source and a reading device at an arbitrary position on a transfer paper conveyance path from feeding a transfer paper to writing an image in order to solve the above-described problems. Another object of the present invention is to provide an image forming apparatus capable of detecting the size of transfer paper fed from a paper feed cassette at a low cost without providing a new CCD system.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the invention according to claim 1, reflected light of an image obtained by applying light emitted from a light source onto a document is transmitted through a first optical path constituted by a mirror or a lens. Transfer paper transport path from feeding the transfer paper to writing the image in an image forming apparatus capable of writing information onto the transfer paper by processing data read by a charge coupled device and converted into an electrical signal A second light source is provided at an arbitrary position of the transfer sheet, and external information of the transfer paper that has crossed this light during transfer of the transfer paper is taken into the charge-coupled device through a second optical path constituted by a mirror or a lens. An image forming apparatus that obtains information converted into an electrical signal is the main feature.
According to a second aspect of the present invention, the change state of the reflected light from the surface of the transfer paper that has crossed the light during the transfer paper conveyance is taken into the charge-coupled device through the second optical path and converted into an electrical signal. An image forming apparatus according to claim 1 for obtaining information is a main feature.
According to a third aspect of the present invention, information obtained by taking conveyance information such as skew or lateral deviation of the transfer paper that crosses light during conveyance of the transfer paper into the charge-coupled device via the second optical path and converting the information into an electric signal is obtained. The main feature of the image forming apparatus according to claim 1 is obtained.
According to a fourth aspect of the present invention, an image is formed according to any one of the first to third aspects, wherein a window is provided at an arbitrary position of the transfer paper conveyance path, and external light is used instead of the second light source. Features the device.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of a first embodiment of an image forming apparatus according to the present invention. In FIG. 1, a reading apparatus 1 includes a first light source 2 for reading an image of a document and a document reading movable portion.
A mirror 4 and a lens 5 are provided as a first optical path for sending reflected light from the original surface obtained by the first light source 2 to the CCD 3. The original image read by the reading device 1 is subjected to digital signal processing.
The latent image obtained on the photoconductor 7 by the optical device 6 irradiating the laser beam with this signal and the developer is developed by the developing roller 8, and then this developed image is fed from the paper feed cassette 10 and is registered. The image is written on the transfer paper P whose writing position and skew have been corrected by the roller 11 via the transfer roller 9, and the transferred image is fixed by the fixing device 12 and discharged.
Here, the second light source 20 disposed in the vicinity of the exit of the registration roller 11 irradiates light in the width direction of the transfer paper P conveyed from the registration roller 11, and is configured by mirrors 21 and 22. The width direction information of the transfer paper P being conveyed can be continuously sent to the CCD 3 through the lens 5 until the rear end passes through the second light source 2 by the optical path 2.
The data taken in by the CCD 3 is digital signal processed, and the size of the transfer paper P can be recognized by calculating the width and length of the transfer paper P with respect to the control time. In the above description, the transfer paper P is accumulated in the paper feed cassette 10, but the transfer paper P is sent to the transport path, and is indicated by a reference symbol P.
[0007]
FIG. 2 is a schematic diagram showing an example of data processing for monitoring the change in the width direction information of the transfer paper being conveyed, which is taken in by the image forming apparatus of FIG. FIG. 3 is a characteristic diagram showing the relationship between the elapsed time t obtained by transferring the transfer paper and the voltage output by the control related to FIG.
In FIG. 2, a hatching range 30 represents a detection range in the transfer paper width direction obtained by the CCD 3 via the second light source 20. Here, based on the detection data of the CCD 3 in FIG. 1, a circuit is constructed in which the voltage F can be continuously obtained as output data for the width of the transfer paper that is traversed while the transfer paper is passing.
FIG. 3 shows the relationship between the elapsed time t obtained by transporting the transfer paper by control and the voltage output, where the voltage F0 is an output with respect to the transfer paper size width, and t0 is the timing at which the leading edge of the transfer paper starts to cross the detection range. , T1 indicates the timing when the trailing edge of the transfer paper leaves the detection range 30.
FIG. 4 is a schematic diagram showing an example of data processing for monitoring the change in the width direction information of the transfer sheet being conveyed taken in by the image forming apparatus of FIG. FIG. 5 is a characteristic diagram showing the relationship between the elapsed time t obtained by conveying the transfer paper by control and the voltage output in relation to FIG. 4 for the left part of FIG. FIG. 6 is a characteristic diagram showing the relationship between the elapsed time t obtained by conveying the transfer paper by control in relation to FIG. 4 and the voltage output for the right part of FIG.
FIG. 7 is a schematic view showing a detection result when a tearing portion is present on the transfer paper surface by the data processing. FIG. 8 is a characteristic diagram showing the relationship between the elapsed time t obtained by the transfer paper conveyance by the control and the voltage output in relation to FIG.
As shown in FIG. 7, when there is a tear A at the end of the transfer paper, output data for the transfer paper with poor quality appears as shown in FIG.
[0008]
FIG. 9 is a schematic view showing a detection result when there is a stain on the transfer paper surface by the data processing. FIG. 10 is a characteristic diagram showing the relationship between the elapsed time t obtained by the transfer paper conveyance by the control and the voltage output in relation to FIG.
As shown in FIG. 9, when there is a dirty portion B on the surface of the transfer paper, output data for the transfer paper having poor quality appears as shown in FIG.
FIG. 11 is a schematic diagram showing a detection result when there is a folded portion at the leading edge of the transfer paper by data processing. FIG. 12 is a characteristic diagram showing the relationship between the elapsed time t and the voltage output obtained by transferring the transfer paper by control in relation to FIG.
As shown in FIG. 11, when there is a folded portion C at the leading edge of the transfer paper, output data for the transfer paper with poor quality appears as shown in FIG.
FIG. 13 is a schematic diagram showing an example of data processing for monitoring the change in the width direction information of the transfer sheet being conveyed taken in by the image forming apparatus of FIG. FIG. 14 is a characteristic diagram showing the relationship between the elapsed time t obtained by the transfer paper conveyance by the control and the voltage output in relation to FIG.
A hatching portion 31 represents a detection range on the left side of the conveyance center by the CCD 3, and a hatching portion 32 represents a detection range on the right side of the conveyance center by the CCD 3.
Based on the detection data of the CCD 3 shown in FIG. 1, a circuit is constructed in which voltages FL and FR are continuously obtained as data for the width of the transfer paper that traverses while the transfer paper is passing. Here, the relationship between the elapsed time t obtained by the transfer paper transfer by the control and the voltage output is shown in FIGS.
The voltages F0 = FL + FR and FL = FR, t0 indicates the timing when the leading edge of the transfer paper starts to cross the detection range, and t1 indicates the timing when the trailing edge of the transfer paper leaves the detection ranges 31 and 32.
In FIG. 13 and FIG. 14, the output data for the transfer paper in which the conveyance is defective indicates the detection result when the transfer paper is skewed.
[0009]
FIG. 15 is a schematic diagram showing an example of data processing for monitoring the change in the width direction information of the transfer sheet being conveyed taken in by the image forming apparatus of FIG. FIG. 16 is a characteristic diagram showing the relationship between the elapsed time t obtained by the transfer paper conveyance by the control and the voltage output in relation to FIG.
In FIGS. 15 and 16, the output data for the transfer sheet in which the conveyance is defective indicates the detection result when the transfer sheet is shifted laterally with respect to the conveyance center line.
FIG. 17 is a schematic diagram showing an example of a data process for monitoring the change in the width direction information of the transfer sheet being conveyed taken in by the image forming apparatus of FIG. FIG. 18 is a characteristic diagram showing the relationship between the elapsed time t obtained by the transfer paper conveyance by the control and the voltage output in relation to FIG.
In FIGS. 17 and 18, the output data for the transfer sheet in which the conveyance is defective shows a case where a delay of td occurs in the conveyance timing of the leading edge of the transfer sheet with respect to the control detection timing t0. .
FIG. 19 is a schematic diagram showing the configuration of the second embodiment of the image forming apparatus according to the present invention. In the image forming apparatus of the first embodiment shown in FIG. 1, a window 40 is provided in the width direction of the transfer paper at the position of the second light source 20 in the apparatus cover or frame portion.
The transfer paper data described above is taken into the CCD 3 by the reflected light of the transfer transfer paper by the external light 41 inserted from this window, and signal processing is performed. Here, it is desirable that a lens is fitted into the window 40 to efficiently concentrate the light on the transfer paper.
If the amount of light is weak, it is possible to determine that the amount of light is insufficient based on the data fetched by the CCD 3, and turn on the alarm or the like to indicate that no signal processing is being performed.
[0010]
【The invention's effect】
As described above, according to the first aspect, by providing the optical path to the light source and the reading device at an arbitrary position in the transfer paper transport path from when the transfer paper is fed to when the image is written, the transfer paper transport is performed. Since the external shape information of the transfer paper that has crossed this light can be sent to the CCD in the existing reader, the transfer paper fed from the paper feed cassette can be supplied at low cost without installing a new CCD system. The size can be detected.
Therefore, since it is not necessary to set the size of the transfer paper, it is possible to eliminate a control defect due to a size setting error, and it is possible to increase the added value of the CCD in the reading apparatus that has been conventionally used only for reading a document. Can be used effectively.
According to the second aspect of the present invention, an optical path to the light source and the reading device is provided at an arbitrary position on the transfer paper conveyance path from the time when the transfer paper is fed to the time when the image is written. Since the surface state information of the transfer paper can be sent to the CCD in the existing reading device, it is possible to detect a transfer paper quality defect at a low cost without providing a new CCD system.
Therefore, it is possible to avoid conveyance jams and writing defects due to poor transfer paper quality, and it is possible to increase the added value of the CCD in the reading apparatus that has been conventionally used only for reading a document and effectively use it. .
[0011]
According to the third aspect of the present invention, an optical path to the light source and the reading device is provided at an arbitrary position in the transfer paper conveyance path from the time when the transfer paper is fed to the time when the image is written, so that the light is crossed during the transfer paper conveyance. Since it is possible to send surface state information that can detect information on correction of the writing position such as skew of the transfer paper and lateral registration deviation to the CCD in the existing reading device, it is possible to install a new CCD system. The writing position can be corrected at a low cost.
Thus, even if there is a deviation from the writing reference of the transfer paper due to paper feeding or conveyance, it is possible to avoid writing problems by discharging the paper without writing or correcting the writing data, The added value of the CCD in the reading apparatus that has been conventionally used only for reading an original can be increased and effectively used.
According to the fourth aspect, since external light is used as the light source, it is not necessary to newly install a light source, and a device for performing each detection can be manufactured at a low cost. Costs can be further reduced by using the same mirrors and lenses required in the optical path as those in the reader.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the configuration of a first embodiment of an image forming apparatus according to the present invention.
FIG. 2 is a schematic diagram illustrating an example of data processing for monitoring changes in the width direction information of a transfer sheet being conveyed that is captured by the image forming apparatus of FIG. 1;
FIG. 3 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper transfer by control in relation to FIG. 2;
FIG. 4 is a schematic diagram showing a detection result when a transfer paper edge is torn by data processing.
FIG. 5 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper conveyance by control related to FIG. 4;
6 is a characteristic diagram showing the relationship between the elapsed time t obtained by conveyance of transfer paper by control in relation to FIG. 4 and the voltage output on the right side of FIG. 4;
FIG. 7 is a schematic diagram showing a detection result when a tearing portion is present on the transfer paper surface by data processing.
FIG. 8 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper transfer by control in relation to FIG. 7;
FIG. 9 is a schematic diagram showing a detection result when there is a stain on the transfer paper surface by data processing.
FIG. 10 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper transfer by control in relation to FIG. 9;
FIG. 11 is a schematic diagram showing a detection result when there is a fold at the leading edge of the transfer paper by data processing.
12 is a characteristic diagram showing a relationship between an elapsed time t obtained by transfer paper conveyance by control and voltage output in relation to FIG. 8. FIG.
13 is a schematic diagram showing an example of data processing for monitoring a change in width direction information of a transfer sheet being conveyed taken in by the image forming apparatus of FIG.
FIG. 14 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper conveyance by control related to FIG. 13;
15 is a schematic diagram showing an example of data processing for monitoring a change in width direction information of a transfer sheet being conveyed taken in by the image forming apparatus of FIG.
FIG. 16 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper conveyance by control in relation to FIG. 15;
17 is a schematic diagram showing an example of data processing for monitoring a change in width direction information of a transfer sheet being conveyed taken in by the image forming apparatus of FIG.
FIG. 18 is a characteristic diagram showing a relationship between an elapsed time t and voltage output obtained by transfer paper conveyance by control related to FIG. 17;
FIG. 19 is a schematic diagram showing the configuration of a second embodiment of an image forming apparatus according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Image reader 2 First light source 3 CCD (Charge Coupled Device)
4 Mirror (first optical path)
5 Lens (first optical path)
6 Optical device 20 Second light source 21 Mirror (second optical path)
22 Lens (second optical path)
40 Window 41 External light P Transfer paper

Claims (4)

The reflected light of the image obtained by applying the light emitted from the light source onto the document is read by the charge coupled device through the first optical path constituted by a mirror, a lens, etc., and the information converted into the electric signal is processed by data processing. In the image forming apparatus capable of writing on the transfer paper, a second light source is provided at an arbitrary position on the transfer paper transport path from when the transfer paper is fed to when the image is written. An image forming apparatus characterized in that the external information of the transfer paper that has crossed the light is taken into the charge-coupled device through a second optical path composed of a mirror, a lens, and the like, and converted into an electrical signal. The change state of the reflected light from the surface of the transfer paper that has crossed the light during the transfer paper conveyance is taken into the charge coupled device through the second optical path to obtain information converted into an electric signal. The image forming apparatus according to claim 1. The transport information such as skew or lateral shift of the transfer paper that crosses light during the transfer paper transport is taken into the charge-coupled device through the second optical path to obtain information converted into an electric signal. The image forming apparatus according to 1. The image forming apparatus according to claim 1, wherein a window is provided at an arbitrary position in the transfer paper conveyance path, and light from the outside is used instead of the second light source.

Images