JPH01319782A - Photosensitive drum device - Google Patents

Abstract

PURPOSE:To eliminate nonconformity of earth in the peripheral direction of a conductive layer by mounting a conductive sleeve on the edge part of a drum, and joining and fixing the conductive layer and the sleeve with conductive adhesive. CONSTITUTION:A laser beam printer is provided with the cylindrical drum 10, which is formed of transparent glass of synthetic resin, and a photosensitive layer 11 is formed on the outside surface of the drum 10. A transparent electrode film 12 is formed between the photosensitive layer 11 and the outside surface of the drum 10, and is exposed to the edge part of the outside surface of the drum 10. The conductive sleeve 37 is attached on the part where the film 12 is exposed, and both of them are joined by the conductive adhesive 38. The sleeve 37 is earthed by a roller 39 which supports the sleeve 37. Thus, nonconformity of earth in the peripheral direction of the layer 12 is eliminated.

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive drum device, and particularly to the structure of an electrode of a photosensitive drum suitable for use in a laser beam printer or the like. KSummary of the Invention The present invention provides a photosensitive drum in which an optical system is disposed inside and a photosensitive layer formed on the outer surface of a transparent cylindrical drum is irradiated with light for exposure. A conductive sleeve serving as an electrode is attached to the electrostatic film below the photoreceptor film via a conductive adhesive, and grounding is established through the conductive adhesive and the conductive sleeve. be. K. Prior Art A photosensitive drum in a conventional laser beam printer is exposed by irradiating laser light from the outside thereof. Therefore, as shown in FIG. 7, an aluminum drum 1 is used, and the charge on the photosensitive layer 2 is grounded through the drum 1 and bosses 3 provided at both ends thereof. This kind of structure can be adopted by
This is because the internal space of the drum 1 is not utilized. [Problems to be Solved by the Invention] The structure shown in FIG. 7 is possible because it does not use the internal space of the drum 1, but it is not suitable for a structure in which exposure is performed from inside the drum 1. I can't. Furthermore, when irradiating light from inside the drum 1, the drum 1 itself needs to be transparent, and cannot be made of aluminum. Furthermore, in order to allow the optical system to run inside the drum 1, it is necessary to open both ends of the drum 1, and it is not possible to support both ends of the drum 1 with the boss 3 as in the conventional case. In other words, a structure is required in which the transparent electrode formed on the outer surface of the transparent drum is grounded by a sleeve or the like that serves as the electrode. The present invention has been made in view of these problems, and is a photosensitive method in which an optical system is disposed inside and a photosensitive layer formed on the outer surface of the drum is exposed from the inside through a transparent drum. The purpose is to propose the structure of electrodes in drums. Means for Solving Problem K] The present invention forms a photosensitive layer on the outer surface of a transparent cylindrical body via a transparent conductive layer, and irradiates light from inside the cylindrical body through the cylindrical body. In the apparatus, a conductive sleeve is attached to an end of the drum, and a conductive adhesive is attached to an end of the drum. The conductive layer and the sleeve are coupled and fixed by the above-described method. K Effect: Therefore, according to the present invention, it is possible to achieve grounding of the conductive layer by means of the conductive adhesive that connects the photosensitive drum and the sleeve.

【Example】

As shown in FIGS. 3, 5, and 6, the laser beam printer according to this embodiment includes a cylindrical drum 10. As shown in FIGS. The drum 10 is made of transparent glass or synthetic resin, and has a photosensitive layer 11 formed on its outer surface, as shown in FIG. A transparent N-pole film 12 is provided between the photosensitive layer 11 and the outer surface of the drum 10.
is starting to form. The photosensitive layer 11 is composed of an organic photoconductor (OPC) layer. Moreover, this 02
The 0 layer 11 has a two-layer structure, and the charge carrier generation 1
1 (CGL) and a charge carrier transport layer (CTL). As CGL, perylene-based, phthalocyanine-based, azo-based, and quinone-based Mn may be mainly used. On the other hand, CTL is a heterocyclic compound such as oxadiazole, oxazole, hydrazone, triphenylmethane,
Triarylamines and the like may be used. Also, photosensitive layer 1
The transparent electrode layer provided below 1 may be composed of an ITO film made of indium oxide or a second oxide (SnOz) film. Next, the optical system provided inside the drum 10 will be explained. A carriage 15 is arranged inside the drum 10, and is supported movably in the axial direction of the drum 10 by a feed screw 16 and a guide rod 17. ing. A case 18 is provided on the carriage 15, and a laser diode 19 and a condensing lens 20 are arranged within this case 18. On the other hand, the condenser lens 20
A prism mirror 21 is provided so as to face the prism mirror 21, and is fixed to the output shaft 23 of the motor 22. A motor 22 is supported on the carriage 15 and is moved together with the carriage 15. Furthermore, the axis of the output shaft 23 of the motor 22, the optical axis of one laser diode, and the condenser lens 20 are made to coincide with the axis of the drum 10. A developing device 27 is disposed on the outer peripheral side of the drum 10 as shown in FIG.
A transfer roller 30 is provided below the drum 10, and the image is transferred onto a recording paper 31 by the transfer roller 30. A static eliminator 32 is arranged inside the drum 10 and below the carriage 15. A cleaning device 33 consisting of a brush roller for roughly cleaning the outer surface of the drum 10 is provided. At the same time, a fixing roller 34 is disposed diagonally below the cleaning device 33. Next, the structure of the grounding of the transparent electrode film 12 of the drum 10 will be explained as shown in FIG. As shown, the photosensitive layer 11 is missing from both ends of the outer surface of the drum 10, so that the electrode film 12 is exposed at both ends of the outer surface of the drum 10. A conductive sleeve 37 is attached to the exposed portion of the electrode film 12, and the coupling between the sleeve 37 and the electrode film 12 is achieved by a conductive adhesive 38. The sleeve 37 has a circular opening 40 in its center, which allows the optical system to be introduced into the drum 10. The sleeve 37 is also supported by rollers 39. The sleeve 37 is grounded via this D-ra 39. In the above structure, the carriage 15 is guided by the guide rod 17 and sent by the feed screw 16, thereby moving inside the drum 10. At the same time, the motor 2 on the carriage 15
2 rotates, the prism mirror 21 attached to the output shaft 23 of the motor 22 is rotated, and the prism mirror 21 reflected from the laser diode 19 is formed on the outer surface of the drum 10. The photoreceptor layer 11 is irradiated with light. Laser light (25 is as shown in Figure 4,
The light passes through the transparent drum 10 and the transparent electrode 12 and is focused on the outer photoreceptor layer 11. Note that since the laser beam 25 is blocked by the carriage 15 in the lower part of the carriage 15, an electronic image is formed on the photoreceptor layer 11 on the outer surface of the drum 10 in the effective irradiation range indicated by the arrow in FIG. That will happen. Such an electronic image is developed with the toner in the toner case 28 of the developing device 27 as the drum 10 rotates, and the toner adhering to the outer surface of the drum 10 is transferred onto the recording paper 31 by the transfer roller 30. will be done. The toner on the recording M2B5 is fixed on the recording paper 31 by heating and pressure by the fixing roller 34. After the transfer, the drum 10 is neutralized by the static eliminator 32 to erase the electronic image, and is also cleaned by the cleaning device 33, completing preparations for forming a new image. In this way, the laser beam printer according to the present embodiment irradiates the laser beam 25 from inside the photosensitive drum 10 to expose the photosensitive layer 11, and the optical system that emits the laser beam 25 is installed inside the drum 10. It has a structure that moves while performing helical scanning. The sleeves 37 at both ends of the drum 10 are therefore provided with openings 40. The photosensitive layer 11 of the drum 10 needs to be a sufficiently grounded conductor in order to charge the surface and electrically neutralize it during exposure.
1 is formed on an electrode film 12 formed on the outer surface of the drum 10. Therefore, in order to support the photosensitive drum 10 and ground the electrode 12, a sleeve 37 that also serves as an electrode is attached to the drum 1.
It is connected to both ends of 0. The sleeve 37 may be made of a conductive metal such as aluminum, or may be molded from a conductive resin. Further, as shown in FIG. 2, when the sleeve 43 is molded from a resin made of an insulator, a sheet metal 44 may be fitted into the sleeve 43. In either case, the sleeves 37, 43 are bonded to the electrode film 12 via the conductive adhesive 38. The purpose of using such a conductive adhesive 38 is to prevent mechanical damage to the transparent electrode film 12, eliminate uneven grounding between the sleeve 37 and the electrode i12, and bond the drum 10 and the sleeve 37. This is because the strength is guaranteed by the adhesive force of the adhesive 38. Note that the sleeve 37 is grounded by a roller 39 that supports it. K Effects of the Invention As described above, in the present invention, the conductive sleeve is attached to the end of the drum, and the conductive layer and the sleeve are bonded and fixed using a conductive adhesive. Therefore, it is possible to eliminate uneven grounding in the circumferential direction of the conductive layer, prevent mechanical damage to the conductive layer by the sleeve that constitutes the electrode, and furthermore, create a strong bond between the sleeve and the transparent cylinder. It becomes possible to gain power.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part showing the structure of an electrode of a drum according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a modified sleeve, and FIG. 3 is a perspective view showing an optical system inside the drum. Figure 4 is a sectional view of the main parts of the drum, Figure 5 is a side view of the optical system inside the drum, Figure 6 is a sectional view taken from line VI to Vl in Figure 5, and Figure 7 is a conventional drum. FIG. 3 is a cross-sectional view of main parts showing the structure of the electrode. The names of the main parts in the drawings are as follows. DESCRIPTION OF SYMBOLS 10... Drum (glass) 11... Photosensitive layer (organic photoconductor layer) 12... Transparent electrode film 15... Carriage 19... Laser diode 20... Condensing lens 21... Prism mirror 25...Laser beam 37...Sleeve 38...Conductive adhesive

Claims (1)

[Claims] 1. Form a photosensitive layer on the outer surface of a transparent cylindrical body via a transparent conductive layer, and expose the photosensitive layer by irradiating light from inside the cylindrical body through the cylindrical body. In the apparatus in which the electric charge of the exposed portion or the non-exposed portion is released through the conductive layer, a conductive sleeve is attached to the end of the drum, and the conductive layer and the sleeve are bonded by a conductive adhesive. A photosensitive drum device characterized in that it is fixed.