JPH07271264A - Image recorder - Google Patents

Abstract

PURPOSE:To enable an image recorder to satisfactorily process the waste toner storing capacity by providing a cleaning means integrally with the storing part of the residual toner and locating the bottom surface of the storing part below the lowermost part of the image carrier. CONSTITUTION:The electrifyer 2 and the optical writing position 6 are arranged below the photoreceptor drum 1, the optical writing unit 7 is disposed in the lower side position of the photoreceptor 1, the developing unit 3 and the cleaning unit 5, and the transfer charger 4 is arranged in the upper side of the photoreceptor drum 1. The paper feeding cassette 8 for feeding the transferring paper to the transfer part is provided in the further lower part below the writing unit 7. The cleaning unit 5 is provided integrally with the storing part for storing the residual toner removed from the photoreceptor drum 1, and constituted so that the bottom surface of the storing part is located further lower than the lowest part of the photoreceptor drum 1. Thus, the storing part of the cleaning unit 5 can be made large in the storing capacity.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus such as a laser printer or a facsimile, and more specifically, it is an optical recording medium for transmitting information according to an image information signal on an image carrier. An optical writing unit for writing and forming an electrostatic latent image is arranged below the image carrier, and a toner image obtained by developing the electrostatic latent image is transferred by a sheet feeding unit. A transfer means for transferring to paper is arranged above the image carrier, and a developing means for developing an electrostatic latent image and a cleaning means for removing residual toner on the image carrier are provided above the optical writing means. The present invention also relates to an image recording device arranged below the transfer means. 2. Description of the Related Art In an image recording apparatus such as a laser printer or a facsimile, a laser beam whose emission is controlled or modulated by an image information signal is used to optically write on a photoconductor through an optical writing unit. The electrostatic latent image formed on the photoconductor is developed by the developing unit into a toner image, which is transferred to the transfer paper fed from the automatic paper feeding unit under the action of the transfer charger, fixed, and recorded. Done. In a conventional recording apparatus of this type, an optical writing unit is provided above a photoconductor, and optical writing is performed at a position above the photoconductor, and after being developed into a toner image, the photoconductor unit is printed. It was usual that transfer was performed on the transfer paper fed with the transfer surface facing upward at the transfer portion between the transfer charger provided in contact with the lower side. In such an image recording apparatus, since the transfer portion is located below the photoconductor, the lower surface of the waste toner tank is lower than the lowermost surface of the photoconductor in order to secure the transfer paper path. In the case of being positioned on the upper side or on the lower side, it is necessary to curve the transport path of the transfer paper after transfer in order to avoid the waste toner tank. At the former position of the waste toner tank, there is a drawback that the capacity of the waste toner tank is unavoidably small, so that the frequency of maintenance increases. At the latter position of the waste toner tank, the risk of jamming due to the curving of the conveying path increases, and the transfer paper carrying the unfixed toner is curved, so that the disturbance of the toner image cannot be avoided. In recent years, an optical writing unit is arranged below an image carrier, a transfer section is arranged above a photoconductor, and a developing unit and a cleaning unit for removing residual toner on the image carrier are described above. An image recording device which is arranged above the optical writing unit and below the transfer section is well known (for example,
JP-A-62-194261 and JP-A-62-1
51871). In all of these known techniques, the waste toner tank is disposed above the lowermost surface of the photoconductor, and therefore the capacity of the waste toner tank is unavoidable. SUMMARY OF THE INVENTION It is an object of the present invention to provide an image recording apparatus which eliminates the above-mentioned drawbacks of the conventional image recording apparatus having the above-mentioned structure. According to the present invention, in order to achieve the above-mentioned object, the cleaning means integrally has an accommodating portion for accommodating the residual toner removed from the image bearing member. It is proposed that the bottom surface of the storage section is located below the lowermost portion of the image carrier. The optical writing means is arranged below the image carrier, the transfer means is arranged above the image carrier, and the developing means and the cleaning means are arranged above the optical writing means. In the image recording apparatus arranged below the transfer means, the cleaning means integrally has a storage portion for residual toner, and the bottom surface of the storage portion is located below the lowermost portion of the image carrier. Since it is located, the storage portion of the cleaning means can be configured to have a sufficient waste toner storage amount. Therefore, the maintenance frequency of the waste toner processing can be minimized, and the maintainability of the image recording apparatus can be improved. Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows a laser printer to which the present invention is applied. Around the photosensitive drum 1, a charger 2, a developing unit 3, a transfer charger 4 and a cleaning unit 5 are arranged in this order in the direction of rotation indicated by an arrow, and between the charger 2 and the developing unit 3. A writing optical unit 7 is provided so that the writing light beam is incident on the photosensitive drum 1 at the position 6 of FIG. In the apparatus of this embodiment, the charger 2 and the optical writing position 6 are arranged below the photosensitive drum 1, and the optical writing unit 7 is below the photosensitive drum 1, the developing unit 3 and the cleaning unit 5. The transfer charger 4 is provided at a side position, and the transfer charger 4 is disposed above the photosensitive drum 1. There is a transfer portion between the transfer charger 4 and the photosensitive drum 1, and a paper feed cassette 8 for feeding the transfer paper to the transfer portion is provided below the optical writing unit 7. As shown in FIG. 1, the cleaning unit 5 integrally has an accommodating portion for accommodating the residual toner removed from the photosensitive drum 1, and the bottom surface of the accommodating portion is lower than the lowermost portion of the photosensitive drum 1. It is configured to be located further below. As a result, the storage unit of the cleaning unit 5 can increase the storage capacity of the residual toner. Transfer papers are separated from the paper feed cassette 8 by a feed roller 9 and a friction pad 10 which is in pressure contact with the feed roller 8 and are sent out one by one.
A large U-turn is made on the side of the developing unit 3, and the pair of registration rollers 11 and 12 provided above the developing unit 3 aligns the timing with the image formed on the photoconductor drum 1 so that the transfer portion is aligned. Is fed to. A fixing unit 13 is provided in the transfer paper path after the transfer, and a paper discharge tray 14 is provided on the discharge side thereof. The writing optical unit 7 is shown in FIGS.
As shown in the figure, the light that blinks in accordance with the image information signal emitted from the laser unit 21 is reflected by the first mirror 22, enters the deflection mirror 24 integrally attached to the shaft of the scanner motor 23, and is kept constant. The angular range is repeatedly deflected. The deflected light is passed through the f-θ lens 25 to the photosensitive drum 1
An image is formed on a straight line at the incident position 6 on the upper side and is corrected so that the projection point moves at a constant speed, and then enters the photosensitive drum 1 via the second mirror 26 and the cylindrical lens 27. Main scanning is performed by deflection of incident light, sub-scanning is performed by rotation of the photosensitive drum 1, an image is written on the photosensitive drum 1 according to an image information signal, and an electrostatic latent image is formed. The components of the writing optical unit 7 are mounted directly on the base cover 28 of the device. Reference numeral 29 is a synchronization detection sensor. The electrostatic latent image formed on the photosensitive drum 1 is developed by the developing unit 3 to form a toner image, and the action of the transfer charger 4 on the transfer paper fed by the pair of registration rollers 11 and 12. Is transferred by. After the transfer, the transfer paper separated from the photosensitive drum 1 is fixed by the fixing unit 13 and discharged to the paper discharge tray 14. On the other hand, the toner remaining on the photosensitive drum 1 after the transfer is cleaned by the cleaning unit 5 to prepare for the next image formation. In this apparatus, as described above, the writing optical unit 7 is provided below the photosensitive drum 1 and the developing unit 3, and the automatic paper feeding unit 8 is further provided below the writing optical unit 7.
Since the transfer section and the pair of registration rollers 11 and 12 are provided above the photoconductor drum 1, the transfer paper sent from the paper feeding unit 8 makes a U-turn outside the developing unit 3 without taking a large space. It can be sent to the pair of registration rollers, and the device can be downsized. The automatic paper feeding unit can be provided on the side of the apparatus. A part 30 of the upper cover of the main body of the apparatus can be flipped up and opened around the shaft 31 at the right end in the drawing of the apparatus, so that the transfer charger 4 can be opened.
And the pair of rollers 11 and 12 of the registration roller pair are
It is adapted to move integrally with a part 30 of the upper cover. Further, the photoconductor drum 1 is supported so that it can be left on the apparatus main body side when the part 30 of the upper cover is opened or can be lifted up integrally with the upper cover. . Therefore, the transfer section or the registration roller pair 1
When a jam of the transfer paper occurs at Nos. 1 and 12, the transfer charger 4 and a pair of registration roller pairs are integrally attached to the part 30 of the upper cover and opened as shown in FIG. The paper transport path is completely open and jam paper can be easily removed. The opening of the part 30 of the upper cover can be facilitated by automatically opening it by removing the latching member by a spring (not shown). Incidentally, as shown in FIG. 5, even if only the upper roller 11 of the pair of registration rollers is integrally attached to the transfer charger 4 on a part 30 of the upper cover and opened.
Effective for removing jammed paper. Further, as shown in FIGS. 6 and 7, when the part 30 of the upper cover is opened, the upper surface of the photosensitive drum 1 is covered with the pair of rollers 11, 12 of the registration roller pair or the upper roller 11. It is convenient to separate and remove the photoconductor from other members when the photoconductor is replaced, if it is selected to be lifted together with the part 30 of the photoconductor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side sectional view showing an overall schematic configuration of an apparatus according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a perspective view showing a configuration of an optical writing unit of the above embodiment. FIG. 4 is an explanatory view showing the operation of the device for opening a part of the upper cover. FIG. 5 is an explanatory diagram showing an operation of another configuration example of the device for opening a part of the upper cover. FIG. 6 is an operation explanatory view of still another configuration example of the device for opening a part of the upper cover. FIG. 7 is an operation explanatory view of still another configuration example of the device for opening a part of the upper cover. [Explanation of Codes] 1 ... Photosensitive drum 3 ... Developing unit 4 ... Transfer charger 5 ... Cleaning unit 7 ... Optical writing unit 8 ... Automatic paper feeding unit 13 ... Fixing units 21 to 27 ... Optical writing unit constituent elements

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Keiji Okamoto             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh

Claims (1)

Claims: (1) An optical writing means for optically writing information according to an image information signal on an image carrier to form an electrostatic latent image is disposed below the image carrier, and A developing unit that arranges a transfer unit that transfers a toner image obtained by developing the electrostatic latent image onto a transfer sheet fed by a sheet feeding unit, and further develops the electrostatic latent image. And cleaning means for removing the residual toner on the image carrier,
In the image recording device arranged above the optical writing unit and below the transfer unit, the cleaning unit integrally includes a storage unit for storing the residual toner removed from the image carrier. An image recording apparatus having the above, and a bottom surface of the storage section is located below a lowermost portion of the image carrier.