JPH0675440A - Image recorder - Google Patents

Abstract

PURPOSE:To eliminate a fear that the hand and clothes of a user are soiled and to prevent the degradation of image quality caused by the incorporation of foreign matter and the deterioration of a developing sleeve by providing a shutter plate in a location to cover the developing sleeve of a developing unit. CONSTITUTION:The developing unit 1 has the shutter plate 34 on its front surface. When the jamming of a recording paper, etc., occur in the upper and lower housing cases, the upper part housing case 52 is lifted upward centering a hinge 51. At this time, the shutter plate 34 is gradually turned clockwise from the standby position of the shutter plate 34 and when the upper part housing case 52 is released from the lower part housing case 50, the shutter plate 34 covers the bottom surface of a photosensitive drum 4. Therefore, the shutter plate 34 covers the photosensitive drum 4 when the upper part housing case 52 is opened, so that a developer and toner can not be exposed outside and an operator can not accidentally touch the photosensitive drum 4 and the developing sleeve 42. Thus, the soiling of the clothes, etc., can be effectively prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image recording apparatus such as a copying machine, a printer or a facsimile.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic image recording apparatus, there is one called a one-cartridge type. In other words, the main process of the electrophotographic method such as the developing device, the photoconductor drum, and the charging device is integrated into one process unit, which can be attached to and detached from the main body, and then replaced one after another to reduce maintenance. belongs to. This type has excellent convenience and is supported by many users. As another method,
There is a two-piece cartridge type in which a process unit is divided into a photoconductor unit in which a photoconductor drum, a cleaner and a charger are integrated and a developing unit. Although the simplicity is inferior to the one-cartridge type, since the photoconductor unit and the developer unit can be replaced according to the life of each,
Compared with the one-cartridge type, it is also advantageous from the viewpoint of environmental and resource issues.

[0003]

However, the two-piece cartridge type image recording apparatus as described above has the following problems. That is, in the state of the developing device alone, the developing sleeve carrying the developer on the surface is exposed, so that it is easy for the user to touch the developing sleeve during operation, which may stain the user's hands and clothes, and There is a possibility that image quality may be deteriorated due to mixing and deterioration of the developing sleeve. In addition, the photosensitive drum also needs some protection because it is easily scratched or dusted when the upper and lower casings are opened during jam processing and is easily deteriorated by light fatigue.

The present invention has been made in order to solve the above-mentioned problems, the user does not easily touch the developing sleeve, there is no danger of the user's hands and clothes being contaminated, and foreign matter is mixed in and developed. It is an object of the present invention to provide an image recording apparatus that does not cause deterioration of image quality due to deterioration of a sleeve and further has less deterioration of a photoreceptor.

[0005]

SUMMARY OF THE INVENTION Therefore, according to the present invention, an image in which an upper casing is attached to a lower casing so as to be openable and closable, a photosensitive drum is accommodated, and at least a developing unit is detachably attached to the upper casing. In the recording apparatus, a shutter plate attached to a position covering the developing sleeve of the developing device unit, and a shutter drum when the developing device unit is attached to the upper housing, the shutter plate from the position covering the developing sleeve to the photosensitive drum. A first shutter plate opening mechanism for moving the shutter plate to a covering position, and a shutter drum from a position where the shutter plate covers the photosensitive drum when combined with the lower casing with the developing unit attached to the upper casing. The second shutter plate opening mechanism for moving the shutter to the opening position is provided.

[0006]

When the developing device unit is set in the image recording apparatus, the upper housing is opened from the lower housing, and the developing device unit is inserted into the upper housing. At this time, the first shutter plate opening mechanism operates to release the shutter plate covering the developing sleeve of the developing unit from the developing sleeve. When the developing device unit is set at a predetermined position in the upper housing, the shutter plate always covers the lower surface of the photosensitive drum which is set. From this state, when the upper housing is rotated with respect to the lower housing to close them, the second shutter plate opening mechanism acts in accordance with the rotational movement of the upper housing, and the photosensitive drum The shutter plate that covers is further rotated to open the photosensitive drum. When the upper case and the lower case are completely set, the shutter plate stands by at a position where it does not interfere with the operation of the developing sleeve and the photosensitive drum unit. Then, when jamming or the like occurs during use of the image recording apparatus, the upper housing is opened from the lower housing. By the action of the second shutter plate opening mechanism, the shutter plate returns to the position where it covers the photosensitive drum, so that the operator does not accidentally touch the photosensitive drum even during jamming or the like.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The image recording apparatus I of the present invention has a lower casing 50 and an upper casing 52 in FIG. 1, and the developing device unit 1 is detachably provided in the upper casing 52 and a photosensitive drum unit is provided. 2 is detachably provided. The developer 3 is stored in the developing unit 1, and the developer 3 is supplied to the photosensitive drum 4 of the photosensitive drum unit 2 by the developing sleeve 42. The photosensitive drum 4 contacts the charged body 5, and a scanner 6 is provided above the charged body 5. The two housings 50,
When 52 is combined, the photosensitive drum 4 contacts the transfer charger 8 attached to the lower housing 50, and the recording paper P is supplied between the photosensitive drum 4 and the transfer charger 8. The recording paper P is supplied from inside a paper feed tray 11 that is detachably provided in the lower housing, the recording paper P is sent out by a paper feed roll 12, and a registration roll 13 is provided in the middle of the conveyance path. ing. The recording paper P passing through the photosensitive drum 4 and the transfer charging device 8 passes through the fixing device 14, is further discharged to the outside by the discharging roll 15, and is stored in the discharging tray 16.

The photosensitive drum unit 2 has a waste toner container 10 as shown in FIG.
A photosensitive drum 4 is rotatably provided at the front of the photosensitive drum 4, the photosensitive drum 4 and the charging body 5 are in contact with each other, and a cleaning unit 9 is provided between the charging body 5 and the waste toner container 10. Sliders 3 are provided on both side plates of the photosensitive drum unit 2.
0 is provided, and this slider 30 is, as shown in FIG.
It engages with slide grooves 55 and 57 provided on unit support plates 54 and 56 provided on both inner sides of the upper housing 52.

The developing unit 1 is shown in FIG. 3 and FIG.
The shutter plate 34 is provided on the front surface thereof as shown in FIG. The lower portion of the shutter plate 34 is rotatably provided on the shaft 33, and the shutter plate 34 has a storage recess 34 a for covering the developing sleeve 42. A shutter opening / closing pawl 36 is provided on one side of the shutter plate 34, and the shutter plate 3 is rotated as the shutter opening / closing pawl 36 rotates.
4 is rotatable. A sector gear 38 is provided on the side opposite to the shutter opening / closing pawl 36, and a torsion spring 40 is provided adjacent to the sector gear 38. The torsion spring 40 always covers the shutter plate 34 in the direction to cover the developing sleeve 42. I am biased. The width of the developing device unit 1 is set to be the same as the width of the photosensitive drum unit 2, and sliders 32, 32 that operate similarly to the slider 30 of the photosensitive drum unit 2 are provided on the side surface of the developing device unit 1. ing.

In FIG. 5, unit support plates 54 and 56 for supporting the two units 1 and 2 are provided in the upper housing 52 with a space left and right therebetween. An opening / closing guide groove 59 is formed in the lower part, and a positioning recess 58 is formed in the back of the guide groove 59. A semicircular recess is formed above the positioning recess 58 so that the shutter opening / closing pawl 36 can rotate. 61 is provided. The torsion spring 40, the shutter opening / closing pawl 36, the opening / closing guide groove 59, etc. form a first shutter plate opening mechanism 100.

Next, the operation of this apparatus will be described. First, a method of mounting the developing device unit 1 and the photosensitive drum unit 2 in the upper housing 52 will be described. The upper housing 52 is opened upward from the lower housing 50 around the hinge 51. In this state, the slider 30 of the photosensitive drum unit 2 is engaged with the slide grooves 55 and 57 of the unit support plates 54 and 56 and slid, and the back surface of the photosensitive drum unit is moved to the unit support plates 54 and 56.
It is brought into contact with the horizontal plate 110 that connects the tips of the. Next, the slider 32 of the developing device unit 1 is inserted into the slide grooves 55 and 57 with the shutter plate 34 facing forward. At the start of this insertion, the shutter opening / closing pawl 36 is in contact with the front end of the opening / closing guide groove 59. However, when the developing device unit 1 is inserted into the upper housing 50, the shutter opening / closing pawl 36 is opened. As shown in FIG. 7, it is rotated clockwise in the drawing and is housed in the slide groove 59.
As a result, the shutter plate 34 is opened and closed by the shutter opening and closing pawl 36.
At the same time, the developing sleeve 42 is opened by rotating clockwise in the drawing. When the developing device unit 1 is in a predetermined position of the upper housing 52, that is, the developing sleeve 42 is in contact with the photosensitive drum 4, the shutter plate 34 slightly rotates counterclockwise in the figure. At this time, the shutter opening / closing claw 36 is housed in the positioning recess 58, and the mounting of the units 1 and 2 on the upper housing 52 is completed.

From this state, when the upper casing 52 is rotated about the hinge 51 so as to close the lower casing 50,
As shown in FIGS. 9 and 10, the sector gear 38 meshes with the upper gear portion 62 of the shutter opening / closing gear column 60 which is erected on the lower housing 50, and the shutter plate rotates as the upper housing 52 rotates. Reference numeral 34 rotates counterclockwise while opening the photosensitive drum 4. Then, as shown in FIGS. 11 and 12, the engagement position of the sector gear 38 is set to the gear portion 6
When it reaches the bottom of 2, the shutter plate 34 takes the standby position to completely open the photosensitive drum 4. When the upper casing 52 is further pushed down from the state of FIG. 11, the sector gear 38 slides along the side surface of the shutter opening / closing gear column 60 while maintaining its rotating position. In this way, the upper housing 52 is completely connected to the lower housing 50, and the preparation for starting image formation is completed. That is, in this state, the photosensitive drum 4 is in contact with the transfer charger 8.
The sector gear 38 and the shutter opening / closing gear column 6
0 and the like form the second shutter plate opening / closing mechanism 200.

During operation of the image forming apparatus, when jamming of recording paper occurs in the upper and lower casings, the upper casing 52 is lifted upward with the hinge 51 as the center. At this time, the shutter plate 34 gradually rotates clockwise from its standby position, and when the upper housing 52 is released from the lower housing 50, the state shown in FIG. Covers the underside of. In this way, the shutter plate 34 is used as the upper housing 52.
When it is opened, the photosensitive drum 54 is covered, so that the developer, that is, the toner is not exposed to the outside, and the operator mistakenly operates the photosensitive drum 4 and the developing sleeve 42.
It is possible to effectively prevent stains on clothes without touching.

[0014]

Since the present invention is constructed as described above,
The user does not touch the developing sleeve easily, there is no risk of soiling the user's hands or clothes, there is no deterioration of image quality due to the inclusion of foreign matter, deterioration of the developing sleeve, and less deterioration of the photoconductor. The device can be used, and the developing device unit and the photosensitive drum unit can be easily assembled.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an embodiment in which the present invention is applied to a laser printer.

FIG. 2 is a perspective view of a photosensitive drum unit.

FIG. 3 is a perspective view of a developing device unit.

FIG. 4 is a perspective view when a shutter of the developing device unit is opened.

FIG. 5 is a schematic perspective view when the upper housing of the laser printer body is opened.

FIG. 6 is an explanatory diagram of an opening / closing operation of a shutter by mounting a developing device unit.

FIG. 7 is an explanatory diagram of a shutter opening / closing operation by mounting the developing device unit.

FIG. 8 is an explanatory diagram of a shutter opening / closing operation when the developing device unit is attached.

FIG. 9 is an explanatory diagram of the opening / closing operation of the shutter by the opening / closing operation of the upper housing.

FIG. 10 is an explanatory diagram of an opening / closing operation of a shutter by an opening / closing operation of an upper housing.

FIG. 11 is an explanatory diagram of the opening / closing operation of the shutter by the opening / closing operation of the upper housing.

FIG. 12 is an explanatory diagram of the opening / closing operation of the shutter by the opening / closing operation of the upper housing.

[Explanation of symbols]

 1 ... Developer unit 2 ... Photosensitive drum unit 4 ... Photosensitive drum 30 ... Slider 32 ... Slider 34 ... Shutter plate 36 ... Shutter opening / closing claw 38 ... Sector gear 42 ... Developing sleeve 50 ... Lower case 52 ... Upper case 59 ... Opening / closing guide Groove 100 ... First shutter plate opening mechanism 200 ... Second shutter plate opening mechanism

Claims (1)

[Claims] 1. An image recording apparatus in which an upper casing is attached to a lower casing so as to be openable and closable, a photosensitive drum is housed, and at least a developing device unit is detachably attached to the upper casing. A shutter plate attached to a position to cover the sleeve, and a first shutter plate opening to move the shutter plate from a position to cover the developing sleeve to a position to cover the photosensitive drum when the developing device unit is mounted on the upper housing. A second shutter that moves the shutter plate from a position covering the photoconductor drum to a position where the photoconductor drum is opened when the mechanism and the lower casing are combined with the developing device unit attached to the upper casing. An image recording apparatus having a plate opening mechanism.