JPH0235485A - Image forming device - Google Patents

Abstract

PURPOSE:To attach and detach a photosensitive body without damaging a cleaning plate by automatically retreating the leading edge of the cleaning plate from the photosensitive drum when it is detached. CONSTITUTION:When the photosensitive drum 9 is removed, a lever 13 abuts on a stopper 11 to the positioned. In this state, the left end of the lever 13 is turned an auxiliary lever 6 counterclockwise by some angle against the force of a spring 5. As a result, the leading edge of the cleaning plate 2 turns to separate from the drum 9. In the process that the drum 9 is descended from above and mounted, the lever 13 turns clockwise against the force of a torsion spring 14 as the drum 9 goes down. Together with the turn, the auxiliary lever 6 turns clockwise due to the action of the spring 5. When the drum 9 is mounted in a prescribed position, the leading edge of the plate 2 presses the drum 9 with prescribed pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention has a cleaning blade for cleaning toner, paper dust, etc. remaining on a photoreceptor drum after transfer,
The 8-light beam is applied to an image forming apparatus in which the drum is attached and detached by moving it in a direction perpendicular to its axis.

[1] In an image forming apparatus using electrostatic photography such as an electrophotographic copying machine or a laser printer, a toner image formed on a photoreceptor through an electrostatic photographic process is transferred to a transfer paper and fixed to form an image. However, toner, paper powder, etc. remaining on the photosensitive drum after transfer are cleaned by a cleaning unit and neutralized, in preparation for the next image formation.

As shown in FIGS. 6 and 7, the cleaning member used in the cleaning unit is a cleaning blade 2 made of an elastic material such as rubber, and a spring 5 is used so that the tip of the cleaning blade 2 is pressed against the eight-light drum. A biased configuration is widely used. There are various ways to bring the cleaning blade into contact with the photoreceptor drum, but as shown in FIG. The cleaning effect is poor in the cleaning blade holding member 3 which is biased by springs 5, 5' installed inside the side plates of the cleaning fan unit γ toggle 1. Toner etc. 8 scraped off from the surface of the photoreceptor drum by the cleaning blade 2 is stored in the cleaning unit case 1. Both ends of the rotating shaft 4 of the blade medical holding member 3 are located at f! of the case 1. It is pivotally supported by the lll plate, and an auxiliary lever 6 is fixed to the outside thereof. All members other than the auxiliary lever 6 are housed inside the case 1. By pushing the auxiliary lever 6 counterclockwise with your fingers against the springs 5 and 5', the tip of the blade 2 is moved against the photoreceptor drum 9.
can be evacuated from.

However, normally, the tip of the blade 2 is in contact with the photoreceptor drum with a predetermined pressing force due to the spring 5. When attaching and detaching by moving it perpendicular to the direction, check whether there will be any problems when removing it by pulling it upward from the attached position, as shown in the order shown in Figure 8 (a), (b), and (c). When the photophilic drum 9 is moved downward from E and installed, the tip of the blade 2 is turned over in the process, thereby deforming the cleaning blade and making it impossible to properly clean toner and the like.

Problems to be Solved by the Invention The present invention takes into consideration the above-mentioned circumstances of the cleaning effect of the conventional structure described above. An object of the present invention is to provide an image forming apparatus which prevents a cleaning blade from turning over due to the attachment/detachment operation of a body drum, and which can always maintain normal leaning.

Solution to Problem 1 In order to solve the above-mentioned problem, the image forming apparatus of the present invention has a cleaning blade at the mounting position of the photoconductor in conjunction with the attachment/detachment movement f size when the photoconductor drum is attached to and detached from the apparatus. The present invention is characterized in that an interlocking mechanism is provided for displacing the cleaning blade such that the tip of the cleaning blade touches the photoreceptor and the tip of the cleaning blade is away from the photoreceptor drum at a position away from the mounting position.

With this configuration, when the photoreceptor drum is attached or detached,
If the photoconductor drum is moved from the predetermined position, the tip of the cleaning blade will automatically retreat from the surface of the photoconductor drum, so there is no risk of the cleaning blade being turned over by the photoconductor drum during the installation process, and the photoconductor When the drum is in a predetermined position, the cleaning blade is in pressure contact with the photoreceptor drum, and the toner is always cleaned normally.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIGS. 1 and 2 are diagrams showing an embodiment in which the present invention is applied to the cleaning unit previously explained in FIGS. 6 and 7. Therefore, members having the same functions will be described with the same reference numerals.

FIGS. 1 and 2 show the vicinity of the side surface of the cleaning case with the Iδ optical drum 9 removed and in the centered state, respectively [7], and FIG. 3 is an exploded perspective view thereof.

Case T's j! ′! A stud 10 is provided protruding from the outer surface of the 11 plate, and a lever 13 is rotatably supported on the stud 10. Note that reference numeral 15 is a retainer link. The other end of a torsion spring 14, one end of which is supported at a point 12 on the side plate of the case 1, is hooked to the lever 13, thereby biasing the lever J3 to rotate counterclockwise, so that the photoconductor In the state shown in FIG. 1 with the drum 9 removed, the lever 13 is positioned in contact with a stopper 11 fixed to the side plate of the case. In this state, the left end of the lever 13 in the drawing rotates the auxiliary lever 6 by a certain angle counterclockwise against the force of the springs 5 and 5'. Rotate away from the body drum.

The right end of the lever 13 is bent upward, and as shown in FIG.
In the process of lowering and mounting the optical main drum 9 from above, the outer peripheral surface of the bearing portion 9a at the axial end of the photoreceptor drum comes into contact with the upper end surface of the upwardly bent portion of the lever 13, and the photoreceptor drum As the lever 13 is lowered, the lever 13 rotates clockwise as shown by the arrow (A) against the force of the torsion spring 14, and as a result, the auxiliary lever 6 rotates (jE) of the springs 5, 5'.
Depending on the use, rotate clockwise as shown by the counter arrow (b).
When the photoreceptor drum 9 is mounted at a predetermined position, the tip of the cleaning grade 2 is pressed against the photoreceptor drum with a predetermined pressing force. Note that at this time, a gap is created between the lever 13 and the auxiliary lever 6, so that the pressure applied to the tip of the cleaning blade 2 is not obstructed.

The method of fixing the auxiliary lever 6 to the rotating shaft 4 of the blade 2 is to fix the rotating shaft 4 in a cross-sectional shape other than circular (for example, D-shaped) or with parallel planes on both sides, as shown in Figure 4. Various known methods can be used, such as making the mounting hole of the auxiliary lever the same shape, or making the shaft and the mounting hole circular as shown in FIG. 5, and press-fitting or screwing them.

Due to the configuration described above, the tip of the cleaning blade is separated from the photoconductor drum when the photoconductor drum and the predetermined mounting f are removed from the vertical position, and the tip of the cleaning blade is separated from the photoconductor drum when the photoconductor drum is mounted in a predetermined position. The photoconductor drum is lowered with the tip separated from the photoconductor drum, and then the cleaning blade is rotated, and at the set position, the cleaning blade is brought into contact with the photoconductor drum with the correct pressing force. can.

According to the present invention, the tip of the cleaning blade is automatically retracted from the photoconductor drum when the photoconductor drum is attached or detached, so that the photoconductor can be attached or detached without damaging the cleaning blade. .

[Brief explanation of the drawing]

FIG. 1 is a top view of the cleaning unit with the photoreceptor drum removed, according to an embodiment of the present invention, and FIG.
11 is a side view of the cleaning uni-soto for explaining the action when the photoconductor drum is attached, FIG. 3 is an exploded perspective view thereof, and FIG.
5 and 5 are perspective views showing an example of a method of fixing the shaft of the cleaning blade and the auxiliary lever, FIG. 6 is a sectional view showing an example of a conventional cleaning grade, FIG. 7 is a perspective view thereof, and FIG. 3A, 3B, and 3C are sectional views sequentially showing the deformation of the cleaning blade when the photosensitive drum is mounted without retracting the cleaning blade. Cleaning case, 2. Cleaning blade, 3. Cleaning blade holding member, 4. Cleaning blade rotating shaft, 5.5'... Pressure spring, 6. Auxiliary lever 10-.
・Stud, 1.1.12...Stud 13...
・Lever, 14...Twist spring Fig. 1 Fig. 2 Fig. 3 (a) (b) (C)

Claims (1)

[Scope of Claims] An image forming apparatus in which the tip of a cleaning blade is movable toward and away from a photoconductor drum, and the photoconductor drum is moved in a direction perpendicular to its axis to be attached to and detached from the apparatus, when the photoconductor drum is attached to and detached from the photoconductor drum device. In conjunction with the attachment/detachment operation, the tip of the cleaning blade comes into pressure contact with the surface of the photoconductor when the photoconductor is attached to a predetermined position, and the tip of the cleaning blade comes into pressure contact with the surface of the photoconductor when the photoconductor drum is away from the predetermined attachment position. An image forming apparatus comprising an interlocking mechanism for displacing a cleaning blade so as to retract it from a drum.