JPS63266476A - Image forming device - Google Patents

Abstract

PURPOSE:To enable good cleaning of a photosensitive body over a long period of time without being hindered by a blade at the time of maintaining and inspecting the photosensitive body by engagement and disengagement of a holder which holds the blade and an actuating body which operates integrally with an arm attached and detached to and from a body side bracket. CONSTITUTION:The holder 60 which is pivotally supported by a supporting shaft 57 is energized clockwise by a weight 59 to bring the blade 56 into pressurized contact with the surface of the photosensitive body 12, thereby scraping the remaining developer. The holder actuating body 71 and the arm 75 operate integrally via a shaft 73. The body 71 and the front end of the holder 60 space from each other and the blade 56 comes into pressurized contact with the photosensitive body during the operation of the device. The bracket 80 on the body side and the lever end 74 are disengaged from each other when a part of the unit is taken to the outside of the machine. The holder 60 is then lifted and turned clockwise by the actuating body 71 under the energization of the spring at the arm 75 end, by which the blade 56 is parted from the surface of the photosensitive body. The satisfactory cleaning is thus executed for a long period of time with the simple constitution without being hindered by the blade at the time of maintaining and inspecting the photosensitive body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Industrial Field of Application) The present invention relates to image forming apparatuses such as electronic copying machines and laser blinkers, and particularly relates to image forming apparatuses such as electronic copying machines, laser blinkers, etc. An image forming apparatus that is equipped with a cleaning device that scrapes off toner with a cleaning blade for cleaning, and that can be divided into a first unit and a second unit that can come into contact with and separate from the first unit. Regarding the improvement of

(Prior Art) In recent years, image forming apparatuses such as electronic copying machines and laser printers can be divided into a lower unit and an upper unit with the paper transport path as the border, and the paper transport path can be separated as needed. This allows the paper to be opened so that jammed paper can be easily removed, and the internal equipment can be easily maintained, inspected, replaced, etc.

Furthermore, as a cleaning device that is incorporated into an image forming apparatus and cleans developer remaining on an image carrier after image transfer, a blade-type cleaning device is often used because it has features such as simple construction and low cost.

Conventional blade-type cleaning devices have a structure in which the cleaning blade does not come into contact with the image carrier (photoreceptor) during standby, and is brought into pressure contact with the photoreceptor using means such as a solenoid only when activated. The mainstream was to prevent damage to the photoreceptor due to constant contact.

In addition, in some cases, the blade is kept in constant contact with the improvement of the mechanical strength of the photoreceptor.

(Problems to be Solved by the Invention) However, the former non-contact method during standby requires a complicated device and uses expensive parts such as solenoids, resulting in high costs. There were many problems in the design, such as the timing of the contact and separation of the blade and the gap between the blade and the photoreceptor.

In addition, with the latter fixed pressure method, the blade is in pressure contact with the photoconductor, so even if you try to manually rotate the photoconductor during maintenance, it is heavy and difficult to rotate easily, and it is difficult to replace the photoconductor. It not only damages the leprosy but also the edge of the cleaning blade. In addition, a so-called sagging phenomenon, in which the blade is permanently deformed, may occur, or the blade may not contact the photoreceptor evenly, resulting in a problem that a good leaning operation cannot be maintained.

The present invention has been made based on the above-mentioned circumstances, and its object is to form an image that is simple and inexpensive, yet allows reliable leaning operation, and enables good image formation over a long period of time. The aim is to provide equipment.

[Structure of the Invention (Means for Solving the Problems)] In order to solve the above problems, the present invention provides a cleaning device that cleans the developer remaining on the image bearing member after image transfer using a cleaning blade. In the image forming apparatus, the cleaning device is equipped with a cleaning blade, and the cleaning blade is divided into a first unit and a second unit that can be moved into and out of contact with the first unit. a blade holder rotatably provided to hold the cleaning blade so as to bring it into contact with and away from the image carrier; a biasing member that constantly biases the blade holder so that the cleaning blade comes into contact with the image carrier; When the unit is separated from the first unit, the blade holder is rotated against the biasing force of the biasing member to separate the cleaning blade from the image carrier, and the second unit is superimposed on the first unit. The blade holder is then opened and the cleaning blade is brought into contact with the image carrier by the biasing force of the biasing member.

(Function) In the present invention, since the cleaning blade is rotatably supported, even if the cleaning blade is slightly deformed, it can be brought into uniform pressure contact with the image carrier. The cleaning blade is separated from the image carrier when the second unit is separated from the first unit, and the cleaning blade is brought into contact with the image carrier when the second unit is superimposed on the first unit. The cleaning blade does not get in the way during maintenance or replacement of the carrier, improving work efficiency and preventing the edge of the cleaning blade from being damaged. Further, since a drive source such as a solenoid is not required, it can be constructed easily and at low cost.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 2 shows an external appearance of an image forming unit employing the image forming apparatus of the present invention, and FIG. 3 is a schematic longitudinal sectional front view thereof.

In the figure, 1 is a copying device as an image forming device, and 2 also serves as a mounting table on which 8 copying devices 1 are placed, and the paper P as an image recording medium discharged from the discharge section of the copying device 1 is stored as necessary. This is a direction changing/conveying device that receives the paper P and guides it to the copying apparatus 1 again in the same state or in a reversed state in order to form multiple or double-sided images on the paper P. Reference numeral 3 denotes an automatic document feeder that is attached to the top surface of the copying apparatus 1 and automatically supplies the document A.

The copying apparatus 1 is constructed as follows.

That is, numeral 4 in the figure is a main body of the copying machine, and on the top surface of the main body 4 of the copying machine, there is provided a document placement glass 5 as a document placement section on which the document A sent by the automatic document feeder 3 is placed. At the same time, an operation panel 6 is provided on the front edge of the upper surface.

Further, a paper feed cassette 7.
A large-capacity paper feeding device 9 is provided corresponding to the right side of the direction changing conveyance device 2 which also serves as a mounting table. Further, the cassette cover 10 of the upper paper feed cassette 7 serves as a manual paper feed tray 11 for manually feeding paper P as appropriate.

Further, a drum-shaped photoreceptor 12 is arranged approximately in the center of the main body 4 of the copying apparatus. A charging device 13. Exposure optical device 14° developing device 15. Transfer device 16. Peeling device 17. Cleaning device 18. and an afterimage erasing device 19 are arranged in this order.

In addition, a paper feed cassette 7.8 is provided at the lower part of the copying machine main body 4.
and paper 22 fed from the large-capacity paper feeder 9 via the paper feeder 20 . . . , paper P manually fed from the manual paper feed tray 11, and paper led from the direction conversion conveyance device 2. A paper conveyance path 23 is formed that guides P through an image transfer section 21 between the photoreceptor 12 and the transfer device 16 to a paper discharge tray 22 provided on the left side of the main body 4 of the copying apparatus.

Further, a pair of aligning rollers 24 is arranged on the upstream side of the image transfer section 21 of the paper transport path 23, and a fixing device 25 and a pair of paper ejection rollers 26 are arranged on the downstream side.

Further, the exposure optical device 14 has a reflector 30 at its back.
It has an exposure lamp 31 as an exposure light source that is surrounded by and irradiates light onto the document placement section 5, and a first mirror 32 that reflects reflected light from the document placement section 5 in a predetermined direction. a first optical unit 33 movable along;
The zoom lens moves in synchronization with the first optical unit 33 in the same direction at a speed that is half the speed of the first optical unit 33, and converts the optical image reflected by the first optical unit 33 into a variable magnification lens. A second optical unit 37 having a second mirror 35 and a third mirror 36 that reflect light toward the unit 34 is provided. Furthermore, a third optical unit 4 having a fourth mirror 38 and a fifth mirror 39 is provided after the lens unit 34.
o, and a sixth mirror 41 as a fixed reflecting member that reflects the optical image reflected by the third optical unit 40 toward the photoreceptor 12 side.

In addition, the copying apparatus 1 configured in this manner has a lower unit 1a serving as a first unit almost bordering on the paper transport path 23.
and an upper unit 1b as a second unit, and the front cover 4 of the image unit device
5. With the 46 open, operate the lock release lever (not shown) to release the upper unit 1b from the lower unit 1.
It is now possible to separate it from a. Note that since this configuration is well known, detailed explanation will be omitted.

With the exposure lamp 31 turned on, the first optical unit 33 moves along the document placement section 5 at a speed V, and in synchronization with this movement, the second optical unit 37 moves in the same direction at that speed. By moving at a speed of 1/2 of V, the document A placed on the document placement section 5 is scanned and an image is formed on the photoreceptor 12 as an exposed portion which is rotating in advance. It has become.

Then, the photoreceptor 1 is uniformly charged by the charging device 13.
An electrostatic latent image corresponding to the document A is formed on the document A.

The electrostatic latent image formed in this way is developed by facing the developing device 15, and then sent to the image transfer section 21 facing the transfer device 16, and the developer image is passed through a pair of aligning rollers 24. The image is transferred to the paper P that is fed in. Next, the sheet P on which the image has been transferred is peeled off from the photoreceptor 12 by a peeling device 17, and then guided through a conveying path 23 to a fixing device 25 where the image is fixed, and then passed through a pair of paper ejection rollers 26. The paper is discharged to the paper discharge tray 22.

On the other hand, the surface of the photoconductor 12 after the developer image has been transferred to the paper P is cleaned of residual developer (toner) remaining on the photoconductor 12 by facing a cleaning device 18, which will be described later. The erasing device 19 lowers the potential on the photoreceptor 12 below a certain level, making the next copying operation possible.

Further, in the case of multiplex or double-sided copying, the paper is not ejected to the paper ejection tray 22, but is first guided to the direction conversion conveyance device 2 and then guided again to the image transfer section 21 as it is or in a reversed state.

Note that the automatic document feeder 3 includes a transport mechanism section 47 which is provided corresponding to the document table 5 and also serves as a document table cover, and a transport mechanism section 47 which is provided in the vicinity of the document table cover 47 and which is provided in the vicinity of this transport mechanism section 47 and which handles the documents stacked on the document stacking table 48. It has a document supply/reversal mechanism section 49 that sequentially separates documents A one by one and sends them to a conveyance mechanism section 47 and reverses them, and an ejected document stacking table 50 that accommodates the documents discharged from the conveyance mechanism section 47. The structure is as follows.

When only one side of the original A is to be copied, the original A stacked on the original stacking table 48 is separated one by one and the original A is automatically transported to the exposure position by the transport mechanism section 47.
Further, the original after copying is discharged onto a discharged original stacking table 50.

In addition, when copying both sides of the original A, once the one-sided copying is completed, the original A is guided to the original supply/reversing mechanism section 49, the front and back sides are reversed, and the other side is sent to the transport mechanism section 47 again. It is designed to copy.

Further, the cleaning device 18 is shown in FIG.

The configuration is as shown in FIGS. 4 and 5.

That is, numeral 55 in the figure is a main body of the apparatus having an opening in a portion facing the photoreceptor 12, and a cleaning blade 56 is housed within the main body 55 of the apparatus.

The cleaning blade 56 is rotatable by a support shaft 57, and its upper end is held by a blade holder 60 which is always urged counterclockwise by a weight 59 as a biasing member in the state shown in FIGS. 1 and 4. The tip of the lower end is in pressure contact with the circumferential surface of the photoreceptor 12 .

Then, the residual developer a that has adhered to the photoreceptor 12...
This cleaning blade 56 scrapes off the dirt.

A collection blade 6 is also provided at the lower opening edge of the device main body 55.
5 is attached to collect the developer a scraped off by the cleaning blade 56 into the unit main body 55.

Further, a collection auger 66 is provided at the bottom of the apparatus main body 55 to collect the developer in the apparatus main body 55 into an external developer collection box (not shown).

The cleaning device 18 also has a blade holder 60 that is rotated against the biasing force of a weight 59 when the upper unit 1b of the copying device 1 is separated from the lower unit 1a, and the cleaning blade 56 is used as an image carrier. The upper unit 1b is spaced apart from the photoreceptor 12, and the upper unit 1b
When the blade holder 6 is superimposed on the lower unit 1a
A blade contact/separation mechanism 70 is incorporated which opens the cleaning blade 56 (into a free state) and brings the cleaning blade 56 into contact with the photoreceptor 12 using the biasing force of the weight 59.

This blade contact/separation mechanism 70 has a configuration similar to that shown in FIG. That is, a blade holder operating body 71 is disposed near the blade holder 6°, and this blade holder operating body 71 is connected to the device main body 55 via a shaft 73 rotatably supported via a bearing 72. It is configured to be able to move together with a lever 74 as an external operating member.

Further, a spring support arm 75 is attached integrally to the lever 74, and the other end of a tension spring 77, which serves as a biasing body and has one end hooked to a spring support member 76, is hooked to the support arm 75. until the spring support arm 75 comes into contact with the stopper 78, that is, the blade operating body 7
1 is constantly energized until it is separated from the blade holder 60.

Further, the tip end 74a of the lever 74 is located in the movement path of the bracket 8o attached to the frame 79 of the upper unit 1b, as shown in FIG. When the upper unit 1b is superimposed on the lower unit 1a, the tip 74a of the lever 74 is pushed by the bracket 80, and the lever 74 resists the biasing force of the tension spring 77 to the state shown in solid line in FIG. 4), and the blade holder operating body 71 is separated from the blade holder 60 as shown in FIG. Therefore, the blade holder 60 holding the cleaning blade 56 is rotated counterclockwise around the spindle 57 by the TMm of the weight 59 in the state shown in FIGS. 12.

Further, when the upper unit 1b is separated from the lower unit 1a, the bracket 8 attached to the frame 79 of the upper unit 1b is connected from the tip 74a of the lever 74.
0 is separated and the lever 74 is displaced to the state shown by the chain double-dashed line in FIG. 5 (the state shown by the solid line in FIG. 1) due to the biasing force of the tension spring 77.
As shown by the solid line in FIG. 1, the blade holder operating body 71 is in a state where the blade holder 60 is pushed up. Therefore, the blade holder 60 holding the cleaning blade 56 rotates clockwise about the spindle 57 against the weight of the weight 59 in the state shown in FIGS. 1 and 4, and the lower end of the cleaning blade 56 It is in a state separated from the photoreceptor 12.

In this way, in the present invention, since the cleaning blade 56 is rotatably supported, even if the cleaning blade 56 is slightly deformed, it can be brought into uniform pressure contact with the photoreceptor 12 as an image carrier. When the upper unit 1b serving as the second unit is separated from the lower unit 1a serving as the second unit, the cleaning blade 56 is moved away from the photoreceptor 12.
When the upper unit 1b and the lower unit 1a are overlapped with each other, the cleaning blade 56
Since the configuration is such that the contact point is brought into contact with the photoreceptor 12, the photoreceptor 12
The cleaning blade 56 does not get in the way during maintenance or replacement, improving work efficiency. Further, since a drive source such as a solenoid is not required, it can be constructed easily and at low cost.

Furthermore, when replacing the photoreceptor 12, the cleaning blade 56 can be removed from the photoreceptor 12, so there is no need to worry about damaging the edge of the cleaning blade 56, and there is no problem in applying lubricant to the photoreceptor 12. do not have. Furthermore, the cleaning blade 5, which has been a problem for some time,
There is no need to reversely rotate the photoreceptor 12 after the work is completed as a countermeasure against the occurrence of black streaks due to misalignment during contact and separation of the photoreceptor 6, and since there is no need for the motor to rotate in the opposite direction, control and motor selection are facilitated. .

[Effects of the Invention] As described above, in the present invention, since the cleaning blade is rotatably supported, even if the cleaning blade is slightly deformed, it can be brought into uniform pressure contact with the image carrier. Second
When the unit is separated from the first unit, the cleaning blade is separated from the image carrier and the second unit is separated from the first unit.
Since the cleaning blade is brought into contact with the image carrier when the unit is superimposed on the first unit, the cleaning blade does not get in the way during maintenance or replacement of the image carrier, improving work efficiency and eliminating the edge of the cleaning blade. It won't hurt. Further, since a drive source such as a solenoid is not required, it can be constructed easily and at low cost.

As described above, according to the present invention, it is possible to provide an image forming apparatus that can perform a reliable leaning operation despite having a simple and inexpensive configuration, and can form good images over a long period of time.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a schematic vertical cross-sectional view showing the cleaning blade approaching and separating operations of the cleaning device, which is the main part, and FIG. FIG. 3 is a schematic longitudinal sectional front view of the image forming unit device, FIG. 4 is a schematic longitudinal sectional view of the main part of the cleaning device, and FIG. 5 is a part of the blade approach/separation mechanism. FIG. DESCRIPTION OF SYMBOLS 1... Image forming apparatus (copying apparatus), 1a... 1st unit (upper unit), 1b... 2nd unit (lower unit), 12... Image carrier (photoreceptor), 18...
... Cleaning device, 56... Cleaning blade, 57... Support shaft, 59... Biasing body (weight), 60...
...Blade holder, 70...Blade contact M mechanism, 7
1... Blade holder operating body, 73... Shaft, 74...
...Operating member (lever), 77...Biasing body (tension spring), 80...Bracket, a...Residual developer (toner). Applicant's agent Patent attorney Takehiko Suzue J N Partial CN Figure 2

Claims (3)

[Claims] (1) A first unit and a second unit that is equipped with a cleaning device that cleans developer remaining on the image carrier through a cleaning blade after image transfer, and that is movable toward and away from the first unit. In an image forming apparatus that can be divided into two parts, the cleaning device includes a cleaning blade, a blade holder that holds the cleaning blade and is rotatably provided to allow the cleaning blade to approach and separate from the image carrier, and the blade holder. a biasing member that constantly biases the cleaning blade so that it comes into contact with the image carrier; and a blade holder that rotates against the biasing force of the biasing member when the second unit is separated from the first unit. The cleaning blade is moved away from the image carrier, and when the second unit is superimposed on the first unit, the blade holder is opened and the cleaning blade is brought into contact with the image carrier by the biasing force of the biasing member. An image recording device characterized in that it is configured to include a separation mechanism. (2) The blade approach/separation mechanism includes a blade holder operating body rotatably provided near the blade holder, a biasing body that constantly urges the blade holder operating body to move away from the blade holder, and the above-mentioned operating body. The blade holder actuating body is moved from the blade holder by being displaced against the biasing force of the biasing body when the second unit is pushed when the second unit is superimposed on the first unit and is movable integrally with the body. 2. The image forming apparatus according to claim 1, further comprising a releasing actuation member. (3) The image forming apparatus according to claim 1, wherein the biasing member that biases the blade holder is a weight.