JPH08208074A - Image forming device - Google Patents

Abstract

PURPOSE: To simplify wiring for a paper sheet detecting section and make a maintenance work efficient. CONSTITUTION: A paper sheet detecting section is provided with a pair of optical fiber cables 6 to 9 with the ends fastened to the open sections 11a to 13b of upper and lower guide plates 1a to 3b forming a paper sheet passage, via optical fiber connectors 6a to 9b, and the forward ends kept faced to each other via the passage. Also, the optical fiber cable 6 is connected to a light emitting section, and the optical fiber cables 7 and 8 are connected to each other in series between the cables 6 and 9. The cable 9 is connected to a light receiving section. Furthermore, the light receiving section detects the existence of light from the light emitting section via the cables 6 to 9, thereby detecting a recording paper sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and more particularly to improving the efficiency of maintenance work of the image forming apparatus.

[0002]

2. Description of the Related Art In an image forming apparatus of a type in which recording sheets held in layers are conveyed one by one and an image is formed on the recording sheets,
It is necessary to know the position of the recording paper because the recording paper remaining in the paper path may cause a paper jam.

For example, in the jam detection device disclosed in Japanese Patent Laid-Open No. 59-143834, a recording paper that causes paper jam and other recording paper when it is detected that the recording paper is in the paper passage when the power is turned on. The different controls are used to efficiently and safely perform the process after paper jam. Further, in the recording apparatus disclosed in Japanese Patent Laid-Open No. 54-136841, a corner detecting means for detecting the corner of the recording paper is provided near the intersection of the arrangement reference line with respect to two orthogonal sides of the recording paper, and the output of the corner detecting means. The presence / absence of recording paper and the dislocation of the recording paper are detected by.

[0004]

However, in the jam detection device and the recording device described above, in order to detect the recording paper, the photodiode and the photosensor are provided to face each other across the paper passage of the recording paper. In many cases, the presence or absence of the recording paper is detected by detecting whether or not the recording paper is shielded from light. When the photo sensor and the photodiode are provided to face each other across the paper path, the photo sensor and the photo diode are required for each place to detect the presence or absence of the recording paper, and the number of signal lines is the same as the number of the photo sensor and the photo diode. However, the wiring becomes complicated and the replacement work for maintenance becomes complicated.

The present invention has been made to meet such a demand, and an object thereof is to simplify wiring and improve efficiency of maintenance work.

[0006]

SUMMARY OF THE INVENTION An image forming apparatus according to the present invention comprises a paper detection unit for detecting the presence or absence of recording paper or a document, and the paper detection unit is provided at each of the openings of upper and lower guide plates forming a paper passage. One end is fixed with an optical fiber connector,
The front end portion has a pair of optical fiber cables arranged to face each other across the paper path, one optical fiber cable is connected to the light emitting portion, and the other optical fiber cable is connected to the light receiving portion.

Further, a paper detection unit for detecting the presence or absence of recording paper or an original is provided, and the paper detection unit has a tip end fixed to an opening of one of the upper and lower guide plates forming a paper passage with an optical fiber connector. It may have an optical fiber cable for projecting and receiving light, and a reflecting plate provided at a position facing the opening of the other guide plate.

It is also preferable to connect the plurality of openings in series with an optical fiber cable.

[0009]

In the present invention, one end of the optical fiber cable is fixed to the upper and lower guide plates forming the paper passage by the optical fiber connector, and the optical fiber cable is exchanged by attaching and detaching the connector.

Further, the paper detection unit has a pair of optical fibers whose one ends are fixed to the openings of the upper and lower guide plates which form the paper passage by optical fiber connectors, and the front ends of which face each other across the paper passage. The optical fiber cable has a cable, and one optical fiber cable is connected to the light emitting part and irradiates the end part of the other optical fiber cable from the tip fixed to the opening part. The presence or absence of the recording paper is detected by detecting the presence or absence of.

Further, the paper detecting portion includes an optical fiber cable for projecting and receiving light, the front end of which is fixed by an optical fiber connector to one of the openings of the upper and lower guide plates forming the paper path.
If the recording paper interrupts the light emitted by the light projecting optical fiber cable, it has a reflecting plate provided at a position facing the opening of the other guide plate, and the light receiving optical fiber cable will not be exposed to the light. , The presence or absence of incident light to the light receiving optical fiber cable is detected, and the presence or absence of recording paper is detected.

Further, a plurality of openings are connected in series by an optical fiber cable, and a set of light receiving portion and light emitting portion detects recording paper at a plurality of locations.

[0013]

1 is a side sectional view showing an embodiment of an image forming apparatus of the present invention. The image forming apparatus conveys the recording papers stacked and held one by one to form an image on the recording papers. The upper guide plates 1a to 3a and the lower guide plates 1b to 3 are formed.
b, rollers 4a, 4b, 5a, 5b, optical fiber cables 6 to 10 and a control board 10. Upper guide plate 1a
3a and lower guide plates 1b to 3b form a paper path for recording paper, and the recording paper passes through the paper path formed by upper guide plates 1a to 3a and lower guide plates 1b to 3b to rollers 4a to 4a.
It is conveyed by 5b. One end of the optical fiber cable 6 is connected to the control board 10 by the optical fiber connector 6a, and the other end is connected to the opening 11a of the upper guide plate 1a through the optical fiber connector 6b. One end of the optical fiber cable 7 is connected via an optical fiber connector 7a to an opening 11b of the lower guide plate 1b which forms a paper path in pair with the upper guide plate 1a and faces the optical fiber cable 6. The cable 7 together with the optical fiber cable 6 constitutes a detection unit for detecting the presence or absence of recording paper. Similarly, the other end of the optical fiber cable 7 is connected to the opening 12b of the lower guide plate 2b via the optical fiber connector 7b, and the optical fiber connector is provided in the opening 12a of the upper guide plate 2a facing the optical fiber cable 7. One end of the optical fiber cable 8 is connected via 8a. The other end of the optical fiber cable 8 is connected to the opening 13a of the upper guide plate 3a through the optical fiber connector 8b, and the opening 13b of the lower guide plate 3b facing the optical fiber cable 8 is connected through the optical fiber connector 9a. And one end of the optical fiber cable 9 is connected. The other end of the optical fiber cable 9 is connected to the control board 6 via an optical fiber connector 9b. In this way, the upper guide plates 1a to 3a and the lower guide plates 1b to
Since the photodiode and the photo sensor are not provided in 3b, it is not necessary to solder the signal line and the like, and the optical fiber cables 6 to 9 are connected to the upper guide plates 1a to 3a and the lower guide plate 1b with a simple optical fiber connector. The optical fiber cables 6 to 9 can be fixed to 3b, and maintenance and replacement work of the optical fiber cables 6 to 9 is facilitated.

The control board 10 serves as a calling portion and a light receiving portion.
For example, a photodiode and a photosensor (not shown) are provided, and the light generated by the photodiode is incident on the optical fiber cable 6 via the optical fiber connector 6a, for example. The light incident on the optical fiber cable 6 is emitted from the other end of the optical fiber cable 6 toward the end of the optical fiber cable 7. Here, when there is no recording paper between the upper guide plate 1a and the lower guide plate 1b, the light emitted from the optical fiber cable 6 toward the optical fiber cable 7 is incident on the optical fiber cable 7. Similarly, when there is no recording paper between the upper guide plate 2a and the lower guide plate 2b and between the upper guide plate 3a and the lower guide plate 3b, the light incident on the optical fiber cable 7 is And an optical fiber connector 9b passing through the optical fiber cable 9.
The light enters the control substrate 10 via the and illuminates the photo sensor. Further, for example, when there is a recording paper between the upper guide plate 2a and the lower guide plate 2b, the light emitted from the optical fiber cable 7 is blocked by the recording paper and cannot be incident on the optical fiber cable 8. The photosensor on the substrate 10 cannot be illuminated.

As described above, when there is no recording paper in each paper path, the light generated from the photodiode on the control board 10 illuminates the photosensor, and when there is a recording paper in any paper path, the control board 10 is used. Since the light generated from the photodiode above does not illuminate the photo sensor, the control board 1
It is possible to detect whether or not there is a recording sheet in each sheet path by a pair of photodiodes and a photo sensor on the 0. For this reason,
The number of photodiodes and photosensors can be reduced, and the configuration is simplified, which facilitates maintenance work. When a photo sensor and a photodiode are installed at each inspection position for inspecting the presence or absence of recording paper, the control board 1
However, in the present invention, the recording paper is detected only by sequentially connecting the adjacent inspection positions with the optical fiber cables 6 to 9, so that the number of cables can be reduced. The number can be reduced and maintenance work becomes easier.

Further, if the optical fiber cables 6 to 9 have the same length, the optical fiber cables 6 to 9 become compatible with each other, and the number of components can be reduced.

In the above embodiment, the paired optical fiber cables 6 to 9 are connected to the openings 1 of the upper and lower guide plates 1a to 3b.
1a to 13b are fixed so as to face each other across the paper path, and the presence or absence of recording paper is detected by detecting the presence or absence of light emitted from one optical fiber cable 6 to 8 by the other optical fiber cable 7 to 9. However, the presence / absence of the recording paper may be detected by detecting the presence / absence of light reflected on the opposite side of the paper passage. For example, as shown in the side cross-sectional view of FIG. 2, the paper detection unit has a tip portion in the opening portions 11a to 13a of the upper guide plates 1a to 3a forming the paper passage and the optical fiber connector 17 to.
Light emitting and receiving optical fiber cables 6 to 9 fixed by 19.
And the reflecting plates 14 to 16 provided at positions opposite to the openings of the other guide plate, and when there is no recording paper, the light projecting optical fiber cables 6 to 8 to the reflecting plates 14 to 16 are provided.
The light radiated toward the is reflected by the reflection plates 14 to 16 and radiated to the light receiving optical fiber cables 7 to 9. If there is a recording sheet, the reflection plates 14 to 16 are not exposed to light, and the light receiving optical fiber cables 7 to 9 are not exposed to the light from the reflection plates 14 to 16, and the presence or absence of light from the reflection plates 14 to 16 is checked. By detecting, the presence or absence of the recording paper can be detected.

Further, in the case of the above-mentioned light emitting and receiving optical fiber cables 6 to 9, without providing a reflection plate, the openings 11a to 13a in which the tips of the light emitting and receiving optical fiber cables 6 to 9 are fixed.
The presence or absence of the recording paper may be detected by applying a dark color to the surfaces of the guide plates 1b to 3b facing to each other so as not to reflect the light and detecting the reflected light from the recording paper.

In the above embodiment, the adjacent inspection positions are sequentially connected by the optical fiber cables 6 to 9 to detect the presence or absence of the recording paper, but it is necessary to know the presence or absence of the recording paper and the position of the recording paper. In this case, as shown in the side sectional view of FIG. 3, the control board 10 is individually provided with the optical fiber cables 20a, 20b to 22a, 22b at locations where it is necessary to detect the position of the recording paper.
You may connect with. In this case, since a plurality of photodiodes and photosensors are required, there is a high possibility of failure.
0 can be concentrated and only the control board 10 needs to be replaced in the case of a failure, so that maintenance work can be performed quickly.

[0020]

As described above, according to the present invention, since the optical fiber cable does not need to be fixed by the substrate or the like, one end of the optical fiber cable is fixed by the optical fiber connector in the opening of the guide plate forming the paper passage. It can be replaced easily.

Further, when one of the optical fiber cables whose front ends face each other across the paper path irradiate the end of the other optical fiber cable, and the light emitted from one optical fiber cable is blocked by the recording paper, Since the other optical fiber cable is not exposed to the light, the presence or absence of the recording paper can be detected by detecting the presence or absence of the incident light to the other optical fiber cable.

Further, the paper detecting section includes an optical fiber cable for projecting and receiving light, the front end of which is fixed by an optical fiber connector to one of the openings of the upper and lower guide plates forming the paper path.
When the recording paper interrupts the light emitted by the light projecting optical fiber cable, it has a reflecting plate provided at a position facing the opening of the other guide plate, and the light receiving optical fiber cable is not exposed to the light. Therefore, it is possible to detect the presence / absence of the incident light to the light receiving optical fiber cable and the presence / absence of the recording paper.

Further, since the plurality of openings are connected in series by the optical fiber cable, the number of sensors for detecting light can be reduced, and the signal line corresponding to the number of recording paper detection points can be provided in the control board. Can be prevented from being connected to.

Further, since the recording paper can be detected without providing a sensor or the like at each recording paper detection location, the maintenance work is facilitated and the durability is improved.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2 is a side sectional view of an image forming apparatus using a reflection plate.

FIG. 3 is a side sectional view of an image forming apparatus that detects a recording sheet position.

[Explanation of symbols]

 1a to 3a Upper guide plate 1b to 3b Lower guide plate 4a to 5b Roller 6 to 9 Optical fiber cable 6a to 9b Optical fiber connector 10 Control board 11a to 13b Opening portion 14 to 16 Reflector plate

Claims (3)

[Claims] 1. A paper detection unit for detecting the presence or absence of recording paper or a document, wherein the paper detection unit has one end fixed to an opening of an upper and lower guide plate forming a paper passage with an optical fiber connector, and a front end thereof. An image characterized in that it has a pair of optical fiber cables arranged to face each other across a paper path, one optical fiber cable is connected to a light emitting section, and the other optical fiber cable is connected to a light receiving section. Forming equipment. 2. A paper detection unit for detecting the presence or absence of recording paper or a document, the paper detection unit having a tip end fixed to an opening of either one of upper and lower guide plates forming a paper passage by an optical fiber connector. An image forming apparatus comprising: a light emitting / receiving optical fiber cable; and a reflecting plate provided at a position facing the opening of the other guide plate. 3. The image forming apparatus according to claim 1, wherein the plurality of openings are connected in series by an optical fiber cable.