JPS62229272A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent a cleaning unit from being brought into contact with a developing roll of a developing device to drop a developer when the cleaning unit is attached or detached, by providing positioning members which are engaged with each other only when the developing device and the cleaning unit are set to respective home positions. CONSTITUTION:A developing device 4 and a cleaning unit 20 are freely attachably and detachably provided in a device body. A recessed part 30 as a positioning member is formed in the lower end part of the cleaning unit 20. A projecting part 31 as a positioning member is provided in the lower end part of the developing device 4. The developing device 4 is inserted or detached from above or the side of a copying machine and has the projecting part 31 fitted to the recessed part 30 of the cleaning unit 20 and is positioned. Thus, the cleaning unit 20 is stopped by the projecting part 31 of the developing device 4 and cannot be inserted or detached when the developing device 4 is set to the device body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to an image forming apparatus that is applied, for example, as an electronic copying machine.

(Prior Art) Generally, an electronic copying machine is equipped with a photosensitive drum within its main body, and a charger, a developing unit, a transfer unit, a peeling charger, and a cleaning unit are arranged around the photosensitive drum in order along the rotating direction. etc. are installed.

When copying, the circumferential surface of the photosensitive drum is uniformly charged by a charger, and the charged surface is irradiated with reflected light from the original to form an electrostatic latent image.
Thereafter, this electrostatic latent image is visualized by supplying a developer from a developer. Then, the developed image is transferred to paper by the action of a transfer charger, and then separated by a release charger, and then the paper is conveyed to a fixing device, where the transferred image is fixed and the paper is ejected. ing.

Further, the developer remaining on the photosensitive drum during transfer of the image is removed and cleaned by a cleaning unit.

Incidentally, the cleaning unit and the developing unit are set to be removably inserted into the main body of the apparatus, and are removed from the main body for maintenance and inspection.

(Problem to be Solved by the Invention) However, in the conventional apparatus, the cleaning unit and the developing unit were configured to be able to be freely inserted into and removed from the apparatus main body. There is a problem in that when the unit is inserted and removed, it slides into contact with the developing roller of the developing unit, causing developer to fall and staining the inside of the apparatus body.

In addition, the cleaning unit and the developing unit cannot be positioned relative to each other, and their set positions shift from each other, making it impossible to clean properly.Furthermore, even if the cleaning unit is set out of position, it cannot be determined. When a charger is attached to the cleaning unit, there are problems such as a portion of the copied image being missing due to poor connection of the charger electrode or horizontal deviation of the charged area with respect to the exposed area. there were.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to restrict the insertion and removal of the cleaning unit when the developing unit is set in the main body of the apparatus, and to prevent the developing unit and cleaning unit from being inserted or removed. It is an object of the present invention to provide an image forming apparatus that can be set in a fixed position.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides an apparatus main body, a developing unit and a cleaning unit that are removably installed in the apparatus main body, The developing unit and the cleaning unit are provided with a positioning member that engages with the cleaning unit only when they are set in fixed positions to position both units, and the positioning member does not engage when the developing unit and the cleaning unit are set in the main body of the apparatus. The present invention is characterized in that insertion and removal of the cleaning unit is restricted.

(Function) The positioning means positions the developing unit and the cleaning unit at regular positions, and also regulates the order of insertion and removal into the main body of the apparatus.

(Embodiment) Hereinafter, the present invention will be described with reference to an embodiment shown in the drawings. FIG. 3 shows an electronic copying machine, and numeral 1 in the figure is the main body of the copying machine. A photosensitive drum 2 is rotatably provided in the center of the copying machine main body 1, and a charging charger 3, a developing device 4, a transfer and peeling charger 5 are arranged around the photosensitive drum 2 in order along the rotational direction. , 6, a cleaning device 7, and a static elimination charger 8 are provided.

Further, an optical system 9 is provided on the upper side of the copying machine main body 1, and this optical system 9 includes a light source 11 that irradiates light onto a document set on a document table 10, and a light source 11 that irradiates light onto a document set on a document table 10, and a light source 11 that emits light reflected from the document. It is composed of a lens 12 that guides the photosensitive drum 2.

Further, a paper feed cassette 13 is provided on the lower side of the copying machine main body 1.
is provided, and sheets P are taken out one by one from this paper feed cassette 13 by rotation of a paper feed roller 14. This taken out paper P is conveyed along the conveyance path 15. On the conveyance path 15, there are disposed a scissor roller 16, the transfer/separation charger 5, 6, a fixing roller 17, and a discharge roller 18. Note that 19 is a paper discharge tray.

Next, the cleaning device 7 will be explained in detail. In the figure, reference numeral 20 denotes a cleaning unit, and a cleaning blade 21 is provided on the upper side inside this cleaning unit 20, and the lower end portion of the cleaning blade 21 is in contact with the photosensitive drum 2. Reference numeral 22 denotes a collection screw provided below the cleaning blade 21. The cleaning unit 20 is inserted into and removed from the front side of the copying machine main body 1 along the axial direction of the photosensitive drum 2, and has a charger on the end surface on the insertion side as shown in FIG. A side electrode 23 and a leaf spring 24 are provided in a protruding manner. Further, the rear frame 25 of the copying machine main body 1 is provided with a power supply electrode 26 into which the charger side electrode 23 is inserted and connected. Further, a through hole 28 is bored on the opposite side of the cleaning unit 20 from the insertion end thereof, and the through hole 28 faces the screw hole 27 formed in the front frame 32 of the copying machine main body 1.
The cleaning unit 20 is fixed by screwing the screw 29 in the screw hole 271C through the through hole 28. Further, a recess 30 serving as a positioning member is formed at the lower edge of the cleaning unit 20.

On the other hand, as shown in FIG. 2, a protrusion 31 as a positioning member is protruded from the lower end of the developing device 4. As shown in FIG. The developing device 4 is inserted into and removed from above or from the side of the copying machine, and its convex portion 31 is fitted into the concave portion 30 of the cleaning unit 20.

Next, the cleaning unit 20 and the developing device 4
This section explains how to attach and detach the . First, when installing the cleaning unit 20 and the developing device 4, first insert the cleaning unit 20 from the front side, and while pressing the leaf spring 24 against the rear frame 25, connect the charger side electrode 23 to the rear frame 25. The cleaning unit 20 is fixed by inserting it into the power supply electrode 26, then inserting the screw 29 into the through hole 28 of the IJ-Jung unit 20 and screwing it into the screw hole 27 of the rear frame 25.

Next, insert the developing device 4 from above or from the side of the copying machine main body 1, and push the convex portion 31 into the IJ-Jung unit 2.
0 into the recess 30 and position it to complete the installation.

In this installation, if the developing device 4 is installed first, even if the cleaning unit 20 is inserted next, the insertion side end surface will come into contact with the protrusion 31 of the developing device 4, and the cleaning unit 20 will be installed. I can't.

On the other hand, when taking out the cleaning unit 20 and the developing device 4, first take out the developing device 4, then loosen and remove the fixing screw 29 of the cleaning unit 20, and take out the cleaning unit 20 from the front side.

At this time of taking out, even if you try to take out the cleaning unit 20 first, the recess 3 of the cleaning unit 20
0 is fitted into the protrusion 3 of the developing device 4, the cleaning unit 20 cannot be removed.

As described above, the cleaning unit 2o cannot be attached with the developing device 4 attached, and the cleaning unit 20 cannot be removed with the developing device 4 attached. Since the toner does not come into contact with the developing roller 4a of the toner 4, it is possible to prevent the toner from falling.

Further, if the cleaner unit 20 is not fixed to the front frame 32 with the fixing screws 29, it will be pushed back by the reaction force of the leaf spring 24, so forgetting to tighten the screws can be prevented and it can be reliably set in the fixed position. Therefore, it is possible to prevent copying image defects due to poor connection of the charger electrode section 23 attached to the cleaner unit 204C and lateral deviation of the charged area with respect to the exposed area.

Note that the present invention is not limited to the above embodiment,
Of course, various modifications can be made within the scope of the gist.

〔Effect of the invention〕

As explained above, according to the present invention, the cleaning unit does not come in contact with the developing roller of the developing device and drop the developer when the cleaning unit is attached or detached, and it is possible to prevent the inside of the device from becoming contaminated. It is effective.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a perspective view showing a cleaning unit, FIG. 2 is a perspective view showing a developing unit, and FIG. 3 is a configuration diagram showing the inside of an electronic copying machine. . DESCRIPTION OF SYMBOLS 1... Copying machine main body (apparatus main body), 4... Developing unit, 20... Cleaning unit, 30... Recessed part (positioning member), 31... Convex part (positioning member). Applicant's agent Patent attorney Takehiko Suzue Figure 3

Claims (2)

[Claims] (1) An apparatus main body, a developing unit and a cleaning unit that are removably installed in the apparatus main body, and a developing unit and a cleaning unit that are installed in the developing unit and the cleaning unit and that engage only when they are set in each other's fixed positions. An image forming apparatus comprising: a positioning member for positioning, the positioning member regulating insertion and removal of the cleaning unit when the developing unit is set in the apparatus main body. (2) The cleaning unit is provided with a biasing member that biases the cleaning unit in the opposite insertion direction when the cleaning unit is inserted into the apparatus main body, and the cleaning unit is pushed against the biasing force of the biasing member. The image forming apparatus according to claim 1, wherein the cleaning unit is set in a fixed position when the cleaning unit is moved and fixed.