JPH03225372A - electrophotographic equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an electrophotographic apparatus.

In a conventional electrophotographic apparatus, an electrostatic latent image is formed by exposing an image carrier whose outer peripheral surface is charged by a charging section to light from an exposure section. Conventional exposure methods include a deflection scanning exposure method in which a beam of light emitted from a light source such as a laser diode is scanned onto an image carrier using a rotating mirror, but recently a self-scanning exposure method has been developed. There is. As this self-scanning exposure section, a large number of edge-emitting type EL devices are constructed by surrounding a thin active layer containing active elements, such as zinc sulfide, from above and below with dielectric layers, and sandwiching this between pairs of electrodes. (
A line head consisting of linearly arranged electroluminescence (electroluminescence) elements is housed in a case to form an exposure area, and by applying a voltage to each electrode, light is emitted from the end face of the active layer toward the image carrier. There is an exposure method that does this.

Since the self-scanning exposure unit is small and has a small focal length, it requires a charging unit that charges the image carrier before forming an electrostatic latent image;
The process kit is arranged close to the outer periphery of the image carrier together with a process kit including a static eliminator that eliminates electricity from the outer periphery of the image carrier and a cleaning unit that wipes the outer periphery of the image carrier. On the other hand, the image carrier is rotatably supported by a support body that is detachably held in relation to the paper conveyance path for jam removal and the like.

Problems to be Solved by the Invention Although the process kit including the exposure section is expensive, it can withstand image formation on approximately 100,000 sheets of paper. On the other hand, the image carrier reaches the end of its life after forming images on approximately 10,000 sheets of paper, and is replaced most frequently. However, since this image carrier is difficult to disassemble from the support, the image carrier must be disposed of together with the support, resulting in high running costs.

If another process kit is attached to the support, it is necessary to remove the process kit from the support when replacing the image carrier, and this operation is also troublesome.

Means for Solving the Problems A charging section, a transfer section, a developing section, and a large number of light emitting elements are arranged in a straight line around an image carrier provided inside a main body, each applying an electric charge to the image carrier. In an electrophotographic apparatus, an electrophotographic apparatus is provided with a self-scanning type exposure section, and a fixing section is disposed downstream of the transfer section in a paper conveyance path, and the electrophotographic apparatus supports at least the exposure section and is detachable from the main body. Holding parts for removably holding the shaft parts at both ends of the image carrier were disposed on both sides of the support mounted on the image carrier.

Since only the image carrier that is frequently replaced can be removed from the support and disposed of, running costs can be reduced. The relative position between the image carrier and the exposure section can be adjusted only once by attaching it to the image carrier, and the relative position between the image carrier and the exposure section can be kept constant even when the support is attached to and detached from the main body for jam removal. can be maintained.

Example An embodiment of the present invention will be described based on the drawings.

FIG. 1 is a longitudinal side view showing the overall structure. In the figure, 1 is the main body of the electrophotographic apparatus, and a paper guide plate 3 is attached to the rear end of the main body 1 so as to be rotatable about a fulcrum 2. A paper receiver 4 is held at the upper part so as to be rotatable and detachable about a fulcrum 4a. Further, the main body 1 is provided with a paper conveyance path 9 for conveying the sheets 7 and 8 in the paper feed cassettes 5 and 6, which are paper feed sections. Guide plates 10 are provided facing each other to guide the sheets 7 and 8 toward the sheet receiver 4. Further, the paper conveyance path 9
includes paper feed rollers 12 and 13 that contact the uppermost sheets of paper 7 and 8 of the paper feed cassettes 5 and 6; A transfer section 15 applies an electric charge to the sheets 7 and 8, a static eliminator 16 removes the electric charge remaining on the sheets 7 and 8, and the sheets 7 and 8 that have passed through the transfer section 15 are sandwiched and the transferred images on the sheets 7 and 8 are fixed. Fixing section 1
7 and peeling claws 11 that come into contact with the fixing roller of the fixing unit 17 and peel the paper from the fixing roller are sequentially arranged from upstream to downstream. Further, inside the main body 1, a six-image bearing unit 18 and a developing section 22 are detachably attached.

The image carrier unit 18 includes the image carrier 14, a charging section 19 that applies charges to the image carrier 14 before forming an electrostatic latent image, and a charging unit 19 that exposes the image carrier 14 to uniformly charge the outer periphery of the image carrier 14. It is formed by mounting a static eliminating section 20, a cleaning section 21, an ozone filter 24, and a self-scanning exposure section 27 on a support 18a. Furthermore, the support body 18
A space portion 18b is formed between the charging portion 19 and the ozone filter 24.

Further, as is clear from FIG. 3, the charger 19
has an outer casing 26 having a channel-shaped cross section to surround the discharge wire 25. This outer casing 26 is formed by drawing an aluminum material and has a holding section 28 that holds a self-scanning exposure section 27. This exposure section 27 is connected to a circuit board 29 fixed to a holding section 28.
, an edge light emitting board 3o fixed to this circuit board 29, and an imaging lens 3 fixed to the holding part 28 by a screw 31.
2 and more. On the edge emitting substrate 30, although not shown, a large number of edge emitting type EL elements, which are light emitting elements, are arranged in a straight line. Further, a drive circuit component 35 for driving the edge emitting board 30 and a connector 36 are provided on the circuit board 34 fixed to the upper surface of the support body 18a. The edge light emitting board 30 is connected intermittently to a drive circuit (not shown) fixed inside the main body 1 via a circuit board 29, a cable 33, a circuit board 34, and a connector 36. Furthermore, the holding section 28 includes the charging section X9.
An insulating plate 37 that partitions between the image carrier 14 and the exposure section 27 is fixed in close proximity to the image carrier 14 . A cover 38 is held by the support 18a and covers the exposure section 27. Further, the support body 18a is provided with a discharge toner storage chamber 5.
0 is formed, and a lid 5 opens and closes this discharged toner storage chamber 50.
1 holds the ozone filter 24.

Further, as shown in FIG. 2, shaft portions 41 for rotatably holding the image carrier 14 are provided on both sides of the support body 18a.
A shaft hole 42 serving as a holding portion into which both ends of the shaft hole 42 are fitted, and a protrusion 44 projecting laterally are formed. These shaft holes 42
has a slit 43 passing through its center in order to detachably hold the shaft portion 41 in a direction perpendicular to its axis.

That is, by fitting both ends of the shaft portion 41 into the shaft hole 42 while elastically deforming the slit 43, the image carrier 14 can be attached to the support body 18a. Further, the shaft portion 41 of the image carrier 14 is inserted into the U-shaped groove 46 of the upper opening formed in the frame 45 provided inside the main body 1, and the projection portion 44 is applied to the upper edge of the frame 45. By making contact with each other, the image carrier unit 18 can be attached to the frame 45. Further, a hook 48 for pressing the shaft portion 41 against the bottom of the groove 46 is rotatably attached to the frame 45 about a fulcrum shaft 47 .

These hooks 48 are biased by toggle springs 49 to both sides of the neutral position. Further, these hooks 48 have knobs 48a at their upper portions.

In such a configuration, the image carrier 14 is charged by the charging section 19 every cycle during rotation, and the charged portion is scanned with a light beam from the exposure section 23, so that an electrostatic latent image is formed.
This electrostatic latent image is developed by the developing section 22. On the other hand, the sheets 7 and 8 of the paper feed cassette 5°6 are pulled out between the image carrier 14 and the transfer section 15 by the paper feed roller 12 or 13, so that the developed image on the image carrier 14 is transferred. The image is transferred onto the sheets 7 and 8 by the section 15, and further transferred onto the sheets 7 and 8.
is fixed by the fixing section 17 and discharged to the paper receiver 4. As shown by the imaginary line in FIG.
When rotated downward, this paper guide plate 3 functions as a paper receptacle.

When handling jams or performing maintenance, rotate the paper receiver 4 upward about the fulcrum 4a, disconnect the connector 36, rotate the hook 48 to retreat from the shaft portion 41 of the image carrier 14, and then By taking out the image carrier unit 18 upward, the paper conveyance path 9 can be opened. Further, the image carrier 14 and the exposure section 27 share a common support 18a.
Therefore, even if the image carrier unit 18 is attached to and detached from the main body l for jam removal, the relative position between the image carrier 14 and the exposure section 27 can be kept constant at all times.

When replacing the image carrier 14, as described above, rotate the paper tray 4 upward, remove the connector 36, and engage the hook 48 with the shaft portion 41 of the image carrier 14. The image carrier unit 18 is taken out upward. At this time, the support body 18a widens the slit 43 and allows the shaft portion 41 to pass through the shaft hole 42.
Allow for falling off. That is, the image carrier 14 is
It is separated from 8a and remains in frame 45. Subsequently, by removing the hook 48 from the shaft portion 41, only the image carrier 14 that is frequently replaced can be removed from the frame 45 and discarded alone. Thereby, running costs can be reduced. Furthermore, when replacing the image carrier 14, it is possible to eliminate the need to remove process kits such as the charging section 19, the static eliminating section 20, and the cleaning section 21 from the support 18a. The new image carrier 14 has its shaft portion 41
is attached to the support body 18a, or the shaft portion 41 is inserted into the groove 46 of the frame 45. In this case, the support 18a
When attached to the frame 45, the shaft portion 41 of the image carrier 14
is inserted into the shaft hole 42 through the slit 43. Even if the hook 48 is removed from the shaft 41, the image carrier unit can be removed from the frame 45 by pressing the cover 38 with the protrusion 4b formed on the lower surface of the paper tray 4, as shown in FIG. 18 can be prevented from floating.

Further, although the image carrier 14 is cleaned by the cleaning section 21, the toner may not be completely wiped off. This toner is attracted to the charge on the image carrier 14, but may float away from the image carrier 14 in small amounts in areas where the charge has been removed by receiving light from the exposure section 27. This floating toner moves by taking advantage of the swirling airflow caused by the rotation of the image carrier 14, but is blocked by the insulating plate 37 and does not adhere to the imaging lens 32. Furthermore, the insulating plate 37 can prevent the corona discharge of the charging section 19 from affecting the exposure section 27 .

Furthermore, the swirling airflow generated by the rotation of the image carrier 14 is guided along with the hot air by the insulating plate 37 and is effectively exhausted from the opening 33. Since the ozone filter 24 is present in this exhaust path, the charging section 19 is Ozone generated due to discharge can be effectively decomposed by the ozone filter 24. Furthermore, the space 18b makes it easier for air to flow in the front surface of the ozone filter 24, and the ozone flow can be stored in the space 18b and passed through the ozone filter 24 over time. Therefore, the charged part 1 which becomes an ozone generation source
9, the ozone flow can be rapidly decomposed.

Accordingly, even if a fan is provided to pull the ozone-containing airflow toward the ozone filter 24, the fan can be driven by a small motor, thereby reducing noise. Furthermore, the image carrier unit 18
By taking out the ozone filter 24 from the frame 45 inside the main body 1, the ozone filter 24 can be easily replaced.

In this embodiment, the polarity of the corona discharge of the charging section 19 is negative, and therefore, the toner of negative polarity is attracted to the portion of the image carrier 14 that receives light from the exposure section 27 and is neutralized. Further, the polarity of the corona discharge of the transfer portion 15 for transfer is positive. Since the amount of ozone generated by positive polarity corona discharge is small, the transfer section 1 for transfer is
No ozone filter is required near 5.

Effects of the Invention As described above, the present invention includes a charging section, a transfer section, a developing section, and a large number of light emitting elements arranged in a straight line around an image carrier provided inside a main body, each applying an electric charge to the image carrier. In an electrophotographic apparatus, the electrophotographic apparatus includes a self-scanning type exposure section arranged above, and a fixing section disposed on the downstream side of the transfer section in a sheet conveyance path. Holding parts that removably hold the shaft parts at both ends of the image carrier are provided on both sides of the support that is detachably attached to the main body, so that only the image carrier that is frequently replaced can be removed from the support. can be disposed of, thus reducing running costs and eliminating the need to remove process kits such as the exposure section from the support when replacing the image carrier, which is normally expensive for self-scanning. By holding the exposure part of the mold and the image carrier with a common support, the relative positions of both can be adjusted in one go. This also has the effect that the relative position between the image carrier and the exposure section can be maintained constant at all times.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a longitudinal side view, FIG. 2 is an exploded perspective view showing a support structure for an image carrier and an exposure section, and FIG. 3 is a longitudinal side view thereof. . DESCRIPTION OF SYMBOLS 1...Main body, 7, 8...Paper, 14...Image carrier, 15...Charging section, 17...Fixing section, 18a...
Support, 19...Charging section, 22...Developing section, 27...Exposing section,...Shaft of image carrier, 42...Holding section

Claims (1)

[Claims] A charging section and a transfer section that respectively apply charges to an image carrier provided inside the main body, a developing section disposed between these charging sections and the transfer section, and the transfer section in the paper conveyance path. a fixing section disposed on the downstream side of the main body, a self-scanning exposure section formed by arranging a large number of light emitting elements in a straight line, and a support detachably attached to the main body to support at least the exposure section. What is claimed is: 1. An electrophotographic apparatus comprising: a support member; and a holding member disposed on both sides of the support member to removably hold the shaft portions at both ends of the image carrier.