JPS61107363A - Copying machine - Google Patents

Abstract

PURPOSE:To keep a gap between the surface of a photosensitive drum and the surface of a developing roller highly accurately with a simple structure by engaging a positioning projection projected from the side wall of a case with a guide groove of a guide member. CONSTITUTION:A case 11 of a developing device 10 is set up on a supporting board 12 having a horizontal setting surface 12a. The vertical position and inclination of the developing device 10 are controlled by the supporting board 12. To load the case 11 into the machine body, the positioning projection 20 is engaged with the 3rd guide passage 26 and moved to the 1st guide passage 24 through the 3rd and 2nd guide passages 26, 25 and the projection 20 is tightly abutted upon the side wall of the case 11 in the range of the 1st guide passage 24 to attain horizontal positioning of the case 11. Consequently, the gap between the surface of the roller 15 and that of the drum 14 is kept at a fixed highly accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a copying machine in which the distance between the surface of a photosensitive drum and the surface of a developing roller can be maintained constant simply by installing a developing device in the body of the machine.

BACKGROUND ART When installing a developing device # on a photosensitive drum in a copying machine main body, it is necessary to accurately position the distance between the surface of the photosensitive drum and the surface of the developing roller.

Therefore, in conventional photographic machines, as shown in FIG. 4, two protrusions are provided on the side wall of the case 1 of the developing device.
A contact member 4 having a recess 3 with which the contact member contacts is attached to the main body of the copying machine. Further, a support pin 5 is provided protruding from the case 1, and this support pin 5 fits into a guide groove 7 of a guide member 6 attached to the main body of the copying machine. When mounting the case 1 of the developing device into the machine body, the support pin 5 is guided along the guide lW7, and the mounting is completed when the projection 2 is fitted into the abutment member 4.

At this time, the case 1 is pressed toward the photosensitive drum 8 by a suppressing means P8 formed of a leaf spring or the like, so that the protrusion 2 and the contact member 4 are brought into close contact with each other, and the sleeve of the image roller 9 and the photosensitive drum 8 are pressed against each other. The structure is such that the distance between the two can be maintained constant.

Problems to be Solved by the Invention In the above-mentioned prior art, the abutting member 4 and the suppressing means all need to be specially provided, which increases the number of parts. In addition, the photosensitive drum 8
In order to improve the precision of the interval between the roller and the developing roller 9, the processing precision of the contact member 3 must be increased, which increases manufacturing costs.

SUMMARY OF THE INVENTION The object of the present invention is to provide a complete copying machine which solves the above-mentioned technical problems, has a simple structure, and can maintain the distance between the surface of the photosensitive drum and the surface of the developing roller with high accuracy.

Means for Solving All Problems The present invention has a developing device case mounted thereon, an upper and lower lid, a support stand whose inclination can be adjusted, and a projecting device protruding from the side wall of the case of the image forming device. This copying machine is characterized in that it includes a pair of positioning protrusions, and a guide member 75 in which the protrusions are recessed and a guide groove is formed for horizontal positioning.

Operation: The lateral position of the case can be determined simply by fitting the positioning protrusion protruding from the side wall of the case into the guide groove of the guide member.

FIG. 1 is a simplified fixed sectional view of the vicinity of the developing device of a copying machine according to the present invention. A case 11 of the developing device 10 is mounted on a support stand 12 having a horizontal mounting surface 12ai. With this support stand 12, as will be described later, the present
The vertical position and Ill'jl@ are adjusted and set. A developer 13 is stored in a case 11 of this developing device 10 . Inside the case 11, near the photosensitive drum 14,
Horizontal axis? A developing roller 15 having the following structure is disposed.

When the developing roller 15 is driven to rotate in the direction of the arrow 16, a magnetic brush is formed on its outer periphery, and this magnetic brush comes into contact with the surface of the photosensitive drum 14 on which the original image has been exposed.
Visualized as a toner image. The toner image on the photosensitive drum 14 is transferred onto a copy paper conveyed by a conveyance roller 17, and then fixed by a fixing roller 18 to perform copying.

FIG. 2 is an exploded view of the vicinity of the developing device 10.

A side wall 11a of the case 11 of the developing device 10 is provided with a pair of left and right positioning protrusions 20 that extend horizontally. This protrusion 20 is provided at a position such that the axis of the photosensitive drum 14, the axis of the developing roller 15, and the @ line of the protrusion 20 are in the same horizontal plane when the case 11 is installed in the copying machine body and in its original state. Ran. A pair of guide members 22 are provided outside the side wall of the case 11 . Mounting holes 50, 51.52 are bored in this guide member 22, and screws 53', 54.55 are inserted through these mounting holes 50, 51.52 and formed in the side wall 33 of the copying machine body. The guide member 22 is fixed to the main body of the copying machine by being screwed into the screw holes 56, 57, and 58, respectively.

This guide member 22 is formed with a guide groove 23 into which the positioning protrusion 20 fits. This guide groove 2317
t, a first guide path 24 extending in the vertical direction, a second guide path 25 connected to the first guide path, inclined in a direction away from the photosensitive drum 14, and tapered toward the top, and a second guide path 25; and a third guide path 26 connected to. This first
The walls 24a and 24bld of the guide passage 24 are parallel to each other and extend in a U direction. The interval d1 of the first guide iM path 24 is selected to be approximately equal to the external arrangement of the positioning protrusion 20. The interval d1 between the first guide passages 240, the interval d2 between the second guide passages 25, and the interval d3 between the third guide passages 26 satisfy the relationship di<d2<d3. Therefore, when the positioning protrusion 20 is guided by the guide groove 23, the third guide passage 26,
When guided to the first guide passage 24 via the second guide passage 25, the protrusion 20 is inserted into the inner wall 24 of the first guide passage 24.
A and 24b are brought into close contact. At this time, the inner wall 2
Since 4a and 24b are parallel and extend in the vertical direction, 1! The lateral positioning of the case 11 of the device 10 is ensured.

The support base 12 on which the case 11 is mounted has a horizontal mounting surface 1.
2ai, and rising portions 27 and 28 are provided at both ends extending in the longitudinal direction. Small support stand 12
The width P1 is selected to be larger than %1-iP2 of case 11. Therefore, the present dust agent in the case 11 is prevented from falling onto the conveying roller 17 during the developing operation.

The rising portion 27 has a pair of elongated holes 29 extending vertically.
It has been seen before, and another rising Ri528
K is also provided with a pair of long holes 30 extending vertically. The long holes 29 and 30i screws 31 and 32 are inserted into the screw holes 4 and 35 of the side wall 33 of the copier body, respectively, and the support base 12 is attached to the cypress copy machine body V. .

3 is a sectional view of the vicinity of the guide member 22 and the positioning protrusion 20. FIG. When installing the developing device 100 case 11 into the case, the positioning protrusion 20 is fitted into the third guide passage 26, whereby the positioning protrusion 20
moves through the third guide passage 26 and the second guide passage 25 to the first guide passage @ 24, and in the range of this first guide passage 24, the protrusion 20 abuts exactly as described above. Lateral positioning of case 11 is performed. As a result, the distance between the surface of the developing roller 15 and the surface of the photosensitive drum 14 is maintained constant and with high accuracy. When finely adjusting the distance between the developing EL-715 and the 9-light 1゛ram 14 at 1.0'', use screws 31 and 32'.
(By loosening and displacing the support stand 12 up and down, the height position of the support stand 12 is finely adjusted.
It becomes possible to finely adjust the height and inclination of the roller 5. Therefore, the developing roller 5 can be adjusted to be parallel to the axis of the photosensitive drum 14 .

In this way...l! I After adjusting, screw 3
1. It is firmly screwed into the 32't screw holes 34 and 35, thus completing the fine adjustment work and maintaining the 1llI distance between the surface of the photosensitive drum 130 and the surface of the developing roller 5 with even higher precision. . In this manner, in this embodiment, it is possible to accurately maintain the distance between the developing roller 5 and the photosensitive drum 14 simply by fitting the positioning protrusion 20i into the guide groove 23 of the guide member 22. Further, it is possible to finely adjust the entire support base 12, and therefore it is possible to further improve the accuracy of the distance between the photosensitive drum 14 and the developing roller 5.

l+ Effects of the Invention As described above, according to the present invention, a pair of positioning protrusions protruding from the side wall of the case of the developing device and a guide groove into which the protrusions are fitted are formed for lateral positioning. By providing a guide member and a metal plate, it is possible to easily maintain a constant level of interference between the photosensitive drum and the developing roller. Therefore, there is no need to provide a contact member, a pressing means, etc. as in the conventional case, and manufacturing costs can be reduced. Further, by providing the support stand T-, the developer in the case of the developing device is prevented from falling onto the conveying roller disposed below the case during the developing operation. In addition, by adjusting and setting the vertical position and inclination of the support base, the axes of the photosensitive drum and the developing roller can be aligned in parallel with each other by a fine v4.
It becomes possible to make money.

[Brief explanation of the drawing]

FIG. 1 is a simplified cross-sectional view of the vicinity of the developing device used in the copying example according to the present invention, FIG. 2 is an exploded view thereof, and FIG. 3 is an exploded view of the vicinity of the guide member 22 and positioning protrusion 20.
FIG. 4 is a simplified cross-sectional view of a typical prior art device. DESCRIPTION OF SYMBOLS 10... Developing device, 11... Case, 12... Support stand, 20... Protrusion, 22... Guide member, 23...
・Grid agent Patent attorney Kei Nishi Part 1 Figure 3 Figure 4 7

Claims (1)

[Scope of Claims] A support stand on which a developing device case is mounted and whose vertical position and inclination can be adjusted; a pair of positioning protrusions protruding from the side wall of the developing device case; 1. A copying machine comprising: a guide member having a guide groove formed therein for lateral positioning.