JP2953921B2 - Electrophotographic recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic recording apparatus, and more particularly to an electrophotographic recording apparatus having a detachable process cartridge in which image forming means such as a photosensitive drum and a developing device are housed in a single housing.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic recording apparatus, a photosensitive drum, a charger, a developing device, a cleaning device and other image forming means are housed in a single housing to constitute a process cartridge. In this method, the user exchanges the process cartridge according to the wear of the device. Hereinafter, such a conventional process cartridge will be described with reference to the drawings. FIG. 4 is a perspective view showing a conventional process cartridge and a main body of an electrophotographic recording apparatus.
FIG. 5 is a longitudinal sectional view of the process cartridge.

[0005] In FIG. 5, an image forming section of the electrophotographic recording apparatus comprises a process cartridge 21, an optical writing device 15 and a transfer roller 23. Process cartridge 2
Reference numeral 1 denotes a photosensitive drum 3 built in a frame 22, and a charging roller 4, a developing device 5, and a clear
A ning roller 6 is provided. The developing device 5 includes a toner cartridge 7, a toner stirring member 8, and a toner supply roller 9.
And a developing roller 10.

In FIG. 4, projections 13a and 13b for positioning the process cartridge 21 when the process cartridge 21 is mounted on the main body of the electrophotographic recording apparatus are provided on the side surface of the frame 22 of the process cartridge 21 with the rotating shaft of the photosensitive drum. It is provided on the extension of. On the other hand, the process card of the electrophotographic recording apparatus main body
At both ends of the cartridge mounting portion 26, receiving portions 14a and 14b that engage with the positioning projections 13a and 13b are provided. When the process cartridge 21 is mounted on the main body of the recording apparatus, first, an upper cover (not shown) of the main body is opened, and the process cartridge 21 is inserted in the direction of arrow B. 13b is engaged with the receiving portions 14a and 14b of the apparatus main body, and then the upper cover is closed. As described above, the process cartridge 21 is detachably attached to the main body of the electrophotographic recording apparatus, and the user exchanges the process cartridge 21 in accordance with the consumption of the photosensitive drum 3 or the like, thereby achieving high print quality. Easily kept.

Next, the operation of the electrophotographic recording apparatus having the above configuration will be described with reference to FIG. In the image forming section, a series of electrophotographic processes such as charging, image exposure, and development are performed according to the rotation of the photosensitive drum 3 to form a toner image on the surface of the photosensitive drum 3. On the other hand, the recording medium 24 is transported between the photosensitive drum 3 and the transfer roller 23 by transport means (not shown) of the electrophotographic recording apparatus, and the toner image formed on the surface of the photosensitive drum 3 is transferred here by the transfer roller. Is transferred to the recording medium 24 by the stirrer 23. Thereafter, the recording medium is transported to a fixing device (not shown), and the toner is fixed on the recording medium by the fixing device. In such a series of printing operations, the recording medium may jam inside the main body of the electrophotographic recording apparatus while the recording medium is being conveyed. However, the process cartridge 21 is detachably mounted on the main body of the electrophotographic recording apparatus. Therefore, the jammed recording medium can be easily removed by removing the process cartridge 21 from the apparatus main body.

[0006]

However, in the above-mentioned conventional electrophotographic recording apparatus, the photosensitive drum is opposed to the transfer roller via the recording medium, and the toner image formed on the surface of the photosensitive drum while being in contact with the recording medium. Is transferred to a recording medium by a transfer roller, so that a part of the photosensitive drum is exposed to the outside from the frame of the process cartridge. Therefore, the process cartridge is removed from the main body of the electrophotographic recording apparatus for the purpose of removing the jammed recording medium, etc.
When the detached process cartridge is placed on an obstacle such as a writing instrument or a clip left unattended, the surface of the photosensitive drum exposed to the outside comes into contact with the obstacle and damages the surface of the photosensitive drum. Even a slight scratch on the surface of the photosensitive drum deteriorates the print quality.

Further, as shown in FIG. 4, a mechanism for mounting the process cartridge on the main body of the electrophotographic recording apparatus is as follows.
Only a small positioning projection provided on the frame of the process cartridge and a receiving portion provided on the electrophotographic recording apparatus main body and engaging with the projection, the projection for positioning the process cartridge is used for recording. Even if the process cartridge is not engaged with the receiving portion of the apparatus main body, the deviation or inclination of the process cartridge is small compared to when the process cartridge is normally mounted, so the operator finds a mounting error. Hard to do. If the process cartridge is not properly mounted on the main unit and the cover of the main unit is forcibly closed, the components of the main unit or the process cartridge may be missing, resulting in equipment failure. Becomes

[0008]

According to the present invention, there is provided an electrophotographic recording apparatus comprising a process cartridge in which an image forming means including a photosensitive drum is housed in a frame, and the process cartridge is detachably mounted. In the apparatus, the process cartridge includes legs projecting so as to separate an exposed surface of the photosensitive drum from the mounting surface when the process cartridge is mounted on a substantially flat mounting surface, A projection for positioning the process cartridge on an extension of the rotation axis of the photosensitive drum; the electrophotographic recording apparatus includes a mounting hole for fitting the leg, and a receiving portion for engaging with the projection. When the process cartridge is mounted on the electrophotographic recording apparatus, the legs and the mounting holes are arranged in the horizontal direction of the process cartridge. The mounting position generally regulated, the receiving portion and the projection is characterized by accurately regulating the mounting position of the vertical direction as well as accurately regulate the horizontal mounting position of the process cartridge.

[0009]

With the above construction of the process cartridge and the electrophotographic recording apparatus, the process cartridge is removed from the main body of the electrophotographic recording apparatus for the purpose of removing a jammed recording medium and the like, and the detached process cartridge is removed. When I put the cartridge on a table to temporarily evacuate it,
A gap is formed between the surface of the photosensitive drum exposed to the outside and the table on which the process cartridge is placed. Therefore, even if an obstacle such as a writing instrument is left on the table, the obstacle does not contact the photosensitive drum and the photosensitive drum is not damaged.

When the process cartridge is mounted on the main body of the electrophotographic recording apparatus, if the process cartridge is not mounted at an appropriate position, at least one of the legs of the process cartridge is mounted on the main body of the recording apparatus. Is not fitted into the mounting hole of the process cartridge mounting portion, and the operator can easily find mounting errors because the process cartridge is tilted or appears to rise from the recording apparatus main body.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. Elements common to the drawings are denoted by the same reference numerals.

FIG. 1 is a perspective view showing a process cartridge and an electrophotographic recording apparatus main body of the present invention. In FIG. 1, a process cartridge 1 of the present invention has legs 11a at four corners on the bottom side of a frame 2 of the process cartridge 1.
11b, 11c and 11d are formed integrally. Leg 1
1a to 11d are frames to prevent the recording medium from being conveyed.
The photosensitive drum exposed at both ends of the frame 2 and exposed outside the frame 2 is provided between the photosensitive drums.

The process card of the electrophotographic recording apparatus of the present invention.
The cartridge mounting portion 16 is a part of the base frame forming the sheet transport route. The base frame has a shape having a plurality of functions and is formed by molding. The process cartridge mounting portion 16 has mounting holes 12a, 12b, 12c, and 12 respectively fitted with the legs 11a, 11b, 11c, and 11d of the process cartridge 1.
d. The mounting holes 12a to 12d are also integrally formed by molding when forming the base frame. Since the power supply board and the control board are arranged below the base frame, if the mounting holes 12a to 12d are formed as through holes, metal fittings and dust enter through the openings.
2d has a closed structure. Mounting holes 12a-12d
The size of the legs 11a to 11d is set to the mounting holes 12a to 12d.
It is formed slightly larger than the thickness of the legs 11a to 11d so that it can be easily inserted into the legs 11a to 11d. The depth of the mounting holes 12a to 12d is such that when the legs 11a to 11d are fitted into the mounting holes 12a to 12d, the tips of the legs 11a to 11d are attached to the mounting holes 12a to 1d.
It is formed deeper than the length of the legs 11a to 11d so as not to hit the bottom of 2d.

In FIG. 1, as in the conventional case, the process cartridge 1 is provided on the side of the frame 2 of the process cartridge 1.
Projections 13a and 13b for positioning when the cartridge 1 is mounted on the main body of the electrophotographic recording apparatus are provided on an extension of the rotation axis of the photosensitive drum. On the other hand, at both ends of the process cartridge mounting portion 16 of the electrophotographic recording apparatus main body, receiving portions 14a, 1a engaging with the positioning projections 13a, 13b are provided.
4b is provided. Legs 11a to 11d and mounting holes 12
While a to 12d generally regulate the front, rear, left and right mounting positions, positioning projections 13a, 13b and receiving portions 14a,
14b finely adjusts the front, rear, left and right mounting positions and regulates the mounting positions in the vertical direction.

Next, referring to FIG.
The operation of mounting the cartridge 1 on the main body of the electrophotographic recording apparatus will be described. When mounting the process cartridge 1 on the main body of the recording apparatus, first open the upper cover (not shown) of the main body and insert the process cartridge 1 in the direction of arrow A.
That is, the legs 11a, 11a of the process cartridge 1
The mounting holes 12a, 12b, 12c and 12 of the process cartridge mounting portion 16 of the main body of the recording apparatus are denoted by b, 11c and 11d.
d so as to fit each other, and perform front-rear, left-right positioning. Next, the positioning projections 13a, 13b of the process cartridge 1 are inserted into the receiving portions 14a, 14 of the apparatus main body.
b, and are positioned vertically. At this time, since the front, rear, left, and right positions are already substantially determined by fitting the legs 11a to 11d and the mounting holes 12a to 12d, the positioning projections 13a, 13b are received by the receiving portions 14a,
The process cartridge 1 may be inserted downward while making fine adjustments in front, rear, left and right so as to engage with 14b. After the process cartridge 1 is mounted at an appropriate position on the process cartridge mounting section 16 of the recording apparatus main body in this manner, the upper cover is closed.

FIG. 2 is a side view showing a mounting error of the process cartridge of the present invention. As shown in FIG. 2, when the process cartridge 1 is mounted so as to be shifted from front to back or right and left from an appropriate position of the recording apparatus main body, at least one of the legs 11a to 11d of the process cartridge 1 is attached. Process cartridge mounting section 16 of recording apparatus main body
Not fitted to the mounting holes 12a to 12d of the base frame.
Since the process cartridge 1 collides with the upper surface of the recording medium and appears to be tilted or floated up from the recording apparatus main body, the operator can easily find a mounting error. When all of the legs 11a to 11d are inserted so as to fit into the mounting holes 12a to 12d, the displacement between the front, rear, left, and right is almost eliminated.
If the process cartridge 1 is inserted downward until the process cartridge 1 is fixed, the positioning projection 1
The attachments 3a and 13b do not come off the receiving portions 14a and 14b.

FIG. 3 is a longitudinal sectional view when the process cartridge of the present invention is detached from the main body of the electrophotographic recording apparatus and mounted on a table. When the process cartridge 1 is detached from the main body of the electrophotographic recording apparatus for the purpose of removing a jammed recording medium and the like, and the detached process cartridge 1 is placed on a table for temporary retreat. , Leg 1
Reference numerals 1a to 11d protect the photosensitive drum 3 so that the surface of the photosensitive drum 3 exposed to the outside from the frame 2 of the process cartridge 1 does not come into contact with an obstacle such as the writing implement 17 left on the table. That is, the legs 11a to 11d are connected to the frame 2
Since a gap is formed between the surface of the photosensitive drum 3 exposed to the outside and the table on which the process cartridge 1 is placed, even if the writing tool or the like is left on the table, the writing tool or the like can be used. And the photosensitive drum 3 is not damaged. Usually, the diameter of a writing instrument or the like is about 10 mm, so that the legs 11a to 11d are preferably formed so that the gap is at least 10 to 14 mm.

The present invention is not limited to the above-described embodiment, and various modifications are possible. In the above embodiment, four legs are provided at the four corners of the frame of the process cartridge. However, two legs may be provided on one side of the process cartridge, and one leg may be provided on the other side, for a total of three legs. Good. That is,
One leg is provided at the same position as the legs 11a and 11b.
The same effect can be obtained by providing one leg between 1c and 11d and providing three mounting holes at positions corresponding to these legs in the process cartridge mounting portion of the electrophotographic recording apparatus main body. However, when the process cartridge is placed on the table, stability is better when four legs are provided than when three legs are provided. Further, in this embodiment, the mounting holes 12a to 12d have been described as a closed structure having a bottom, but the mounting holes 12a to 12d may be formed as through holes.
However, in the case of a through hole, a net or the like is attached to the bottom of the through hole in order to prevent metal fittings or the like from dropping from the opening.

[0019]

As described in detail above, by providing the legs in the process cartridge, the process cartridge is temporarily removed from the main body of the electrophotographic recording apparatus for the purpose of removing a jammed recording medium. When the product is placed on a table for evacuation, there is a gap between the surface of the photosensitive drum exposed to the outside and the table on which the process cartridge is placed. The obstacle does not come into contact with the photosensitive drum even if it is damaged, and the photosensitive drum is not damaged.

Further, legs are provided on the process cartridge,
By providing a mounting hole for fitting the leg in the process cartridge mounting portion of the electrophotographic recording apparatus, the process cartridge
When the cartridge is mounted on the main body of the electrophotographic recording apparatus, the legs are inserted into the mounting holes so that the legs are mounted on the process card.
It serves as a guide to guide the cartridge to an appropriate mounting position, facilitating the mounting operation of the process cartridge. If the process cartridge is not mounted at an appropriate position on the electrophotographic recording apparatus, at least one of the legs of the process cartridge fits into the mounting hole of the process cartridge mounting section of the recording apparatus body. However, since the process cartridge is tilted or appears to be raised from the recording apparatus main body, the operator can easily find a mounting error.

As described above, by using the process cartridge and the electrophotographic recording apparatus of the present invention, it is possible to use the process cartridge without worry until the life of the process cartridge is reached while maintaining high print quality, and consumable. The product price can be kept low. Further, by providing the process cartridge with the legs, the process cartridge can be stably placed on the table in the process of assembling the process cartridge, so that the assembling work can be stably performed, so that the assembling work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a process cartridge and an electrophotographic recording apparatus main body of the present invention.

FIG. 2 is a side view showing a mounting error of the process cartridge of the present invention.

FIG. 3 is a longitudinal sectional view when the process cartridge of the present invention is detached from the main body of the electrophotographic recording apparatus and is mounted on a table.

FIG. 4 is a perspective view showing a conventional process cartridge and a main body of an electrophotographic recording apparatus.

FIG. 5 is a longitudinal sectional view of a conventional process cartridge.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Process cartridge 2 Frame 3 Photosensitive drum 11a to 11d Leg 12a to 12d Mounting hole 13a, 13b Positioning projection 14a, 14b Receiving part 16 Process cartridge mounting part

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Takashi Wakana 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (56) References JP-A-2-253287 (JP, A) JP 6-35245 (JP, A) JP-A-2-198458 (JP, A) JP-A 4-120962 (JP, U) JP-A 63-357 (JP, U) (58) Fields investigated (Int) .Cl. ⁶ , DB name) G03G 15/00 550 G03G 21/16-21/18 G03G 13/08-13/095 G03G 15/08-15/095

Claims (1)

(57) [Claims] 1. An electrophotographic recording apparatus having a process cartridge in which an image forming unit including a photosensitive drum is housed in a frame, and wherein the process cartridge is detachably attached, wherein the process cartridge substantially includes the process cartridge. When the process cartridge is mounted on a flat mounting surface, it has legs protruding so as to separate an exposed surface of the photosensitive drum from the mounting surface, and positions the process cartridge on an extension of a rotation axis of the photosensitive drum. The electrophotographic recording apparatus has a mounting hole to be fitted to the leg, has a receiving portion to be engaged with the projection, and mounts the process cartridge to the electrophotographic recording apparatus. At this time, the leg and the mounting hole generally restrict the horizontal mounting position of the process cartridge, and the protrusion and the receiving portion are An electrophotographic recording apparatus, wherein a horizontal mounting position of a process cartridge is accurately regulated and a vertical mounting position is accurately regulated.