JPH02201455A - Image carrier unit - 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 Field of the Invention The present invention relates to an image carrier unit used in printers and copying machines that form images based on electrophotography.

Conventional technology Conventionally, an image carrier unit having an image carrier and a cleaning device is provided, an electrostatic latent image formed on the image carrier is developed with toner in a developing device, and this developed image is transferred to paper by a transfer charger. In an electrophotographic apparatus in which this transferred image is fixed by a fixing roller, waste toner adhering to the image carrier is scraped off by a cleaning blade, and stored in a waste toner storage section of a cleaning device, the waste toner storage capacity of the cleaning device is increased. Some devices are equipped with a waste toner detector, and a detection signal from the waste toner detector is used to warn when it is time to dispose of the waste toner in the toner storage section or to lock the drive section in a state where operation is prohibited.

Problem to be Solved by the Invention Since it is absolutely necessary to avoid the waste toner in the waste toner storage section from scattering around, the performance of the waste toner detector itself and the error in the mounting position of the waste toner detector should be taken into consideration. Therefore, the operating timing of the waste toner detector needs to be set earlier than the actual full timing.

Further, the waste toner detector may detect unevenly distributed waste toner and output a calibration signal earlier than the actual full time. This increases the frequency of cleaning the waste toner storage unit and is inefficient, and if the operating unit is locked in a print inhibit state by the detection signal of the waste toner detector, the work is interrupted even in the middle of the printing process. It's extremely inconvenient because you have to do it.

Furthermore, since the waste toner detector must be assembled into the image carrier unit while being incorporated into the circuit, the structure and assembly work become complicated.

Means for Solving the Problem A support member, which rotatably holds an image bearing member, is detachably attached to the main body which holds a transfer unit, a developing unit, etc., and a waste toner detector is not provided. The support body is provided with a cleaning device having a waste toner storage portion having a storage capacity that is filled for a period equal to or longer than the life period of the image carrier.

The waste toner can be stored in the waste toner storage section of the cleaning device until the life of the working image carrier runs out, thereby eliminating the need to clean the waste toner storage section. The waste toner detector for detecting the capacity of the toner can be omitted, and therefore the structure and assembly work can be simplified.

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

FIG. 1 is a vertical side view showing the overall structure, and in the figure, l is a lower body that constitutes a part of the main body of the electrophotographic printer, and this lower body l connects the base cover 2 and the upper cover 3. One end of a top cover 4 serving as an upper body is attached to the upper part of the lower body 1 so as to be vertically movable. A power source 5 and a circuit board 6 are attached to the base cover 2. The upper cover 3 is provided with a paper transport path 8 for transporting the paper in the paper feed cassette 7, and at the end of this paper transport path 8, the paper is transported to a paper ejection tray 9 formed on the top surface of the top cover 4. A paper ejection path 10 for ejecting the paper towards is connected to this connecting portion, and a switching unit 11 for switching the ejection path of the paper to the side surface of the lower main body l, which is on the extended surface of the paper ejection path 10 or the paper transport path 8 is connected to this connection part. It is provided. Further, the paper conveyance path 8 includes a paper feed roller 12 that contacts the uppermost sheet of the paper feed cassette 7, a start sensor 13 that optically detects the conveyed paper, and a detection sensor 13 that detects the paper that is being conveyed. A registration roller 14 whose rotational movement is controlled by a signal, a transfer section 15 that transfers a developed image on an image carrier 24 to a sheet of paper, which will be described later, a peeling section 16 that separates the paper from the image carrier 24, and a high-voltage power source 17. and a fixing section 18 that clamps the paper that has passed through the transfer section 15 and fixes the transferred image on the paper are sequentially arranged from upstream to downstream.

Further, a basket 19 with vertical openings located above the paper transport path 8 is attached to the upper cover 3, and an image forming unit 2 is detachably housed in the basket 19.
0 consists of an image carrier unit 21 and a developing unit 22. The image carrier unit 21 includes an image carrier 24 rotatably mounted on both sides of a support 23, a charging section 25 that charges the image carrier 24, and a charging section 25 that charges the image carrier 24 and exposes the image carrier 24 to light on its outer periphery. A static eliminator 26 for making electric charges uniform and a cleaning device 27 are attached to a support 23. The cleaning device 27 includes a blade 28 that scrapes off waste toner adhering to the image carrier 24, and a roller 29 that conveys the scraped off waste toner toward the back of the waste toner storage section 27a. The developing unit 22 includes a toner container 30 containing toner, and a developing roller 31 and a stirring blade 32 for stirring the toner. Furthermore, an optical section 33 is attached to the inner surface of the top cover 4 to scan the photosensitive surface of the image carrier 24 with a beam of light.

Further, in the process of rotating the image carrier 24, a charging section 25 is charged, and a laser beam is scanned from the optical section 33 to this charged section to form an electrostatic latent image. The developed image is transferred to the transfer section 15.
The transferred image is transferred to the paper by the following, and this transferred image is fixed in the fixing section 18. Then, the waste toner adhering to the image carrier 24 is scraped off by the blade 28 and conveyed by the roller 29 to the back of the waste toner storage section 27a. The storage capacity of the waste toner storage section 27a is determined so that the period during which the waste toner storage section 27a is filled with waste toner is equal to or longer than the life period of the image carrier 24.

Next, the mounting structure of the basket 19 and the image forming section 20 is shown in FIG. At both ends of the basket 19, there are a pair of handles 34 located above both ends of the image carrier 24.
These handles 34 have guide grooves 36 for vertically movably guiding bearings 35 that protrude from both outer sides of the support body 23 and support the image carrier 24, and the toner container 30. A guide groove 38 is formed for vertically movably guiding a support shaft 37 protruding from both sides. Further, the transfer portion 15 and the peeling portion 16 are positioned on a frame 39 fixed to the upper cover 3 and fixed by screws, and the bearing 35 and the support shaft 37 are positioned on this frame 39. A support portion 40.41 is formed to support the image carrier unit 21, and a stopper 42 is provided upright to abut the lower end of the support body 23 of the image carrier unit 21. These support portions 40, 41 have a concave shape with an opening at the top and a shape that widens toward the top.

Furthermore, the image carrier unit 21 is attached to the frame 39.
A locking means 43 is provided which resiliently engages. This locking means 43 is connected to a lever 4 that rotates around a support shaft 44.
5 and a lever 47 that rotates around a support shaft 46.

The upper portions of these levers 45 and 47 are urged in opposite directions by the urging force of a spring 48. One lever 4
5 has a downward slope 49 that presses the bearing 35 against the bottom of the support part 40 of the frame 39, and this slope 4.
9, and the other lever 47 has a downward slope 52 that presses the bottle 51 protruding from the outer surface of the support 23 of the image carrier unit 21; A slope 53 whose slope direction is changed upward from this slope 52 is formed. Further, the static eliminator 26 which is a component of the image carrier unit 21
A handle 54 is integrally formed on the housing, and handles 56 are integrally formed on both outer sides of the toner container 30. These handles 54, 56 are attached to the basket 19.
The distance to the handle 34 is so close that when the user grips the handle 34, the fingers of the same hand can be placed on the handle 34. Further, these handles 54, 56 are formed with an upward pressing portion 55, 57 and downward finger hook portions 55a, 57a for hanging fingers.

Further, the developing unit 22 includes the developing roller 3.
1 and the stirring blade 32 is fixed, and a power input terminal 59 connected to this motor 58 is provided to protrude downward, and these power input terminals 59 are elastically clamped. knife-shaped connector 60
is fixed to the inner surface of the frame 39. This connector 60 is connected to a power source. moreover,
A proximal portion 61 is formed on the lower surface of the housing of the optical section 33 and faces the upper edge of the support 23 of the image carrier unit 21 with a predetermined gap therebetween.

In such a configuration, when performing jam removal or maintenance, the top cover 4 is rotated upward to open the upper surface of the upper cover 3, and in this state, the handle 34 is grasped to move the basket 19 to the image carrier unit 21 and the upper cover 3. When it is pulled up together with the developing unit 22, the paper conveyance path 8 is opened. Alternatively, the image carrier unit 21 and the developing unit 22 can be moved independently with the basket 19 positioned inside the upper cover 3 by hooking the fingers on the finger hooks 55a and 57a of the handle 54 and 56 and pulling up. It can also be removed.

When disassembling a jam or assembling after maintenance, insert the bearing 35 of the image carrier unit 21 into the guide groove 36 of the basket 19 taken out from the upper cover 3, and insert the support shaft 37 of the developing unit 22 into the guide groove 38. The basket 19 is housed in the upper cover 3 while the handle 34 of the basket 19 is grasped and the bearing 35 and the support shaft 37 are fitted into the support portions 40 and 41 of the frame 39.

Alternatively, the basket 19 stored in the upper cover 3
The image carrier unit 21 and the developing unit 22 are housed in the basket 19 while the bearing 35 or the support shaft 37 is fitted into the guide groove 36.38 and the support portion 40.41. At this time, the bearing 35 whose movement in directions other than the vertical direction is regulated by the guide groove 36 is supported by the upward slope 50 of the lever 44, and the bottle 51 is supported by the upward slope 53 of the lever 47. It is possible to press the pressing part 55 of the handle 54 with fingers that are playing with the grip. By this operation, the lever 45 is rotated counterclockwise against the force of the spring 48 by the force generated by the contact between the bearing 35 and the slope 50, allowing the bearing 35 to move downward. Similarly, the bottle 51 is also supported by the slope 53 of the lever 47, and by pressing down the pressing part 55 of the handle 54,
The lever 47 rotates clockwise against the force of the spring 48 due to the force generated by the contact between the bin 51 and the slope 53, allowing the bin 51 to move downward.

Then, the lever 45 returns to its original state due to the return force of the spring 48.
presses the bearing 35 against the bottom of the support 40 with its downward slope 49, and similarly the lever 47 presses the bearing 35 with its downward slope 52.
The bottle 51 is pressed downward, and the lower edges of both sides of the support body 23 are pressed against the stopper 42.

The developing unit 22 is supported by its own weight with the support shaft 37 positioned on the support portion 41. By positioning the support shaft 37 above the development roller 31 and closer to the image carrier 24 than the center of gravity of the development unit 22, , developing unit 22
The developing roller 31 rotates clockwise around the support shaft 37.
Flanges provided at both ends of the image carrier 24 abut against the outer periphery of the end portion of the image carrier 24 .

As a result, the developing unit 22 is attached to the frame 39 in a stable state with a constant gap between the image carrier 24 and the developing roller 31.

As mentioned above, the basket 19 is pulled up during jam removal and maintenance, but during this process, the bearing 35
presses the downward slope 49 of the lever 45, and the force generated by their contact causes the lever 45 to rotate counterclockwise against the force of the spring 48, allowing the bearing 35 to move upward. Similarly, the bottle 51 presses the downward slope 52 of the lever 47, and the lever 47 rotates clockwise against the force of the spring 48 due to the force generated by the contact between the two, and the bottle 51 moves upward. movement is allowed.

In addition, the lifespan of the image carrier 24 is determined by the decrease in print density and the scale of a counter that detects the number of prints.
The cleaning device 27 is used until the life of the image carrier 24 ends.
The waste toner can be stored in the waste toner storage section 27a of the waste toner storage section 27a, thereby making it possible to omit the work of cleaning the waste toner of the waste toner storage section 27a. can be omitted. Therefore, the structure and assembly work can be simplified without having to worry about attaching the connection terminal of the waste toner detector or processing the connection cord.

Note that a transparent portion may be formed in at least a portion of the waste toner storage portion 27a so that the state of storage of waste toner therein can be observed.

Effects of the Invention Since the present invention is configured as described above, waste toner can be stored in the waste toner storage section of the cleaning device until the life of the image bearing member is exhausted. Cleaning work can be omitted, and
The drive unit is not locked in a print-inhibited state by the detection signal from the waste toner detector, so there is no need to interrupt the process during printing.In addition, the waste toner detection function detects the amount of waste toner. This has the advantage of simplifying the structure and assembly work as well as reducing costs.

2 is a vertical side view showing the overall structure, and FIG. 2 is a vertical side view showing an enlarged support structure of the image forming section.

l...Main body, 15...Transfer section, 22...Development unit.

Claims (1)

[Claims] A support body that rotatably holds an image bearing member is detachably attached to a main body that holds a transfer section, a developing unit, etc., and the period when the image carrier is full of waste toner without a waste toner detector is determined. An image carrier unit characterized in that the support is provided with a cleaning device having a waste toner storage portion having a storage capacity equal to or greater than the life of the carrier.