JPH0525452U - Photosensitive unit of electrophotographic device - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention is compact and can be installed stably.
An object of the present invention is to provide a photoconductor unit equipped with a static eliminator whose position can be easily adjusted with respect to the charging device. [Structure] A photoconductor drum 2, a charging device 4 for charging the photoconductor drum 2, and a photoconductor 4. A static eliminator 3 for removing residual charges is provided. The static eliminator 3 includes a chip type light emitting diode 8, a wiring board 7 on which the chip type light emitting diode 8 is surface-mounted, and the wiring board 7. And a mounting member that is mounted in contact with and is mounted on a member that constitutes the charging device 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a photoconductor unit provided in an electrophotographic apparatus.

[0002]

[Prior Art]

 Electrophotographic devices used in fax machines and laser beam printers are equipped with a charging device, an exposure device, a developing device, a transfer device, a fixing device, a cleaner device, and a neutralizing device around the photosensitive drum. There are different configurations.

That is, this electrophotographic apparatus charges the surface of the photosensitive drum with a charging device while rotating the photosensitive drum, and then exposes the surface of the photosensitive drum with an exposure device to form a latent image and then develops the latent image. The toner image is formed on the surface of the photoconductor drum by the device, then the toner image formed on the surface of the photoconductor drum by the transfer device is transferred to the recording paper, and then the toner image is transferred to the recording paper by the transfer device. The image is fixed. On the other hand, the toner remaining on the surface of the photoconductor drum after the transfer is removed by a cleaning device, and the charge remaining on the surface of the photoconductor drum is removed by a charge eliminating device. That is, the static eliminator includes a static elimination light source, and the light emitted from this light source is applied to the surface of the photosensitive drum to remove residual charges.

Further, in this electrophotographic apparatus, a static eliminator and a charging device are arranged side by side around a photoconductor drum, and the photoconductor drum, the static eliminator and the charging device are attached to one common frame. In some cases, the photoconductor unit is assembled as a photoconductor unit, and the photoconductor unit is detachably attached to the main body of the electrophotographic apparatus.

Conventionally, in the static eliminator of this photoconductor unit, as a method of installing a light source, a lamp or a light emitting diode as a light source is arranged outside the unit frame and attached to the main body of the electrophotographic apparatus. Has been adopted.

However, in the case of this external light source installation method, since the distance from the light source to the surface of the photosensitive drum is long, an optical system is required to guide the light emitted from the light source to the surface of the photosensitive drum, Furthermore, it is necessary to form an opening in the unit frame in order to guide the light from the light source outside the unit frame to the inside of the unit frame, which complicates the configuration of the photoconductor unit. ..

Therefore, a method has been proposed in which the light source is provided inside the unit frame of the photoconductor unit.

However, when a lamp is used as a light source in this internal light source installation method, the amount of heat generated by the lamp is large and the heat generated by the lamp often damages the surface of the photoconductor drum, which makes it difficult to adopt. is there.

Further, when the light emitting diode is used as the light source in the internal light source installation method, the heat of the light emitting diode is small, and thus the heat of the light emitting diode damages the surface of the photosensitive drum. There is an advantage of not doing. Therefore, adoption of a static eliminator installed inside the light emitting diode is being considered.

[0010]

[Problems to be solved by the device]

 However, such a conventional static eliminator installed in the light emitting diode has the following problems.

In the conventional static eliminator, a light emitting diode with a terminal pin is used as the light emitting diode. To attach this light emitting diode with terminal pins, prepare a mounting plate with a hole through which the terminal pin passes, and attach the terminal pin of the light emitting diode from one side of the mounting plate to the pin hole of the mounting plate. The terminal pin of the light emitting diode and the lead wire are connected by soldering on the other surface side of the mounting plate.

Then, with the light emitting diode mounting plate with the surface on which the light emitting diode is located facing the photosensitive drum, with the connection between the terminal pin of the light emitting diode and the lead wire on the back side. It is placed at a predetermined position, and the light emitting diode mounting plate is supported by a mounting member and mounted on the unit frame of the photoconductor unit. Since the back side of the mounting plate has a connection between the terminal pin of the light emitting diode and the lead wire, the light emitting diode mounting plate should be attached to the unit frame to secure the space of this connection. It is attached to the unit frame apart from the inner surface of the wall. Therefore, the unit frame is increased in size by the space of the connecting portion between the terminal pin of the light emitting diode and the lead wire.

Further, since the light emitting diode terminal pins and lead wires are connected to the back side of the light emitting diode mounting plate, the light emitting diode is mounted on the wall of the unit frame. Since the inner surface of the light emitting diode is supported by the inner surface, the support of the mounting plate, that is, the supporting portion of the light emitting diode is unstable and the strength is not sufficient.

Further, when the light emitted from the light emitting diode is applied to the surface of the photosensitive drum charged by the charging device provided adjacent to the charge removing device, the charged surface of the drum is discharged. Therefore, it is necessary to prevent the light emitted from the light emitting diode from being applied to the drum surface charged by the charging device. For this reason, the light emitting diode must be provided at a position where the light emitted from the light emitting diode is not applied to the drum surface charged by the charging device.

However, since the mounting plate on which the light emitting diode is mounted is mounted on the unit frame independently of the adjacent charging device, the position of the light emitting diode with respect to the charging device is accurately adjusted. Is difficult. That is, it is easy to accurately adjust the position of the light emitting diode with respect to the charging device if the mounting plate with the light emitting diode is directly mounted on the charging device, but the mounting plate with the light emitting diode is mounted. The mounting plate cannot be directly mounted on the charging device because there is a connection part between the terminal pin of the light emitting diode and the lead wire on the back side of the.

Therefore, in order to guide the light emitted from the light emitting diode to the surface of the photosensitive drum, a condenser lens may be provided between the mounting plate to which the light emitting diode is attached and the photosensitive drum. However, in this case, the number of parts increases, the structure becomes complicated, and assembly becomes troublesome.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a photoconductor unit including a static eliminator which is small in size, can be stably mounted, and can be easily adjusted in position with respect to a charging device. To do.

[0018]

[Means for Solving the Problems]

 In order to achieve the above object, a photoconductor unit of an electrophotographic apparatus of the present invention comprises a photoconductor, a charging device for charging the photoconductor, and a static eliminator for removing a residual charge of the photoconductor. The static eliminator is composed of a chip-type light emitting diode, a wiring board on which the chip-type light emitting diode is surface-mounted, and a mounting member which is mounted by abutting the wiring board and constituting a charging device. And have.

[0019]

[Action]

 Since the chip-type light emitting diode is surface-mounted, that is, directly mounted on the wiring board on which the wiring portion is formed, the wiring of the lead wire on the back side of the wiring board is unnecessary. Therefore, the static eliminator can be downsized. Further, the wiring board can be directly attached to the mounting member and stably mounted. Further, the mounting member to which the wiring board is mounted can be directly mounted on the power charging device to easily adjust the position of the light emitting diode with respect to the charging device.

[0020]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

The present embodiment is intended for a photoconductor unit in which a photoconductive drum, a cleaning device, a charge eliminating device, and a charging device are integrally formed as shown in FIGS. 1 to 4. is there.

In FIG. 1, reference numeral 1 denotes a unit frame, and a photosensitive drum 2 is horizontally arranged and rotatably supported on the unit frame 1. The photosensitive drum 2 is supported by a shaft 2a and rotated in a direction indicated by an arrow by a rotating device (not shown). The unit frame 1 is provided with a static eliminator 3 above the periphery of the photosensitive drum 2, and a charger 4 is provided adjacent to the static eliminator 3 on the front side in the rotational direction of the photosensitive drum. A cleaning device 5 is provided at a position on the rear side of the charge removal device 3 in the rotation direction of the photosensitive drum.

As shown in FIGS. 2 and 3, the static eliminator 3 includes a light blocking member 6, a wiring board 7 attached to the light blocking member 6, and a plurality of chips which are static erasing light sources attached to the wiring board 7. The light emitting diode 8 is combined.

The light shielding member 6 has an elongated light shielding portion 6a having a length corresponding to the length of the photosensitive drum 2 and an elongated light shielding portion 6b having the same length as the light shielding portion 6a. Since the light portions 6b are combined so that the length directions thereof are parallel to each other and the width directions thereof are perpendicular to each other, an electrically insulating material such as a synthetic resin having an electrically insulating property is provided so as not to adversely affect the charging performance of the charging device 4. The whole is integrally formed with.

In the light shielding member 6, above the periphery of the photosensitive drum 2, the surface of the light shielding portion 6 a on which the wiring board 7 is attached faces the photosensitive drum 1 and the light shielding portion 6 b is adjacent thereto, as described later. Along with the charging device 3, the orientation is set so as to follow the radial direction of the photoconductor drum 2, and the photoconductor drum 2 is arranged along the axial direction. Then, as will be described later, the light-shielding portion 6b of the light-shielding member 6 is brought into contact with the side of the case 10 of the charging device 4 facing the static eliminator 3 and is fixed by adhesive. Thereby, the light shielding member 6 is fixed.

The wiring board 7 is an elongated one having the same length as the light shielding member 6, and is made of an insulating synthetic resin. On one side surface of the wiring board 7, chip-type light emitting diode arrangement locations are set at a plurality of locations spaced in the length direction, and on the wiring board 7, these chip-type light emitting diode arrangement locations are set. And a wiring portion for connecting and disconnecting each chip type light emitting diode 8 is turned on and off.

Chip type light emitting diodes 8 are arranged at the respective chip type light emitting diode arrangement positions on one side surface of the wiring board 7, and electrodes provided on these chip type light emitting diodes 8 are respectively arranged. The wiring portion formed on one side surface of the wiring board 7 is connected and fixed by soldering. Metal pieces 13 1 and 13 3 are arranged on both side edges of one end of the wiring board 7, and are connected and fixed to the wiring portion formed on the wiring board 7 by soldering. One metal piece 13 is connected to the chip type light emitting diode power supply line, and the other metal piece 13 is connected to the ground line of the wiring portion.

An insulating white paint is applied to the mounting surface of the chip type light emitting diode 8 of the wiring board 7.

The wiring board 7 is provided with the chip-type light emitting diode mounting surface facing the photoconductor drum 1, and in the lengthwise direction on the side surface of the light shield member 6 a of the light shield member 6 facing the photoconductor drum 2. Arranged along and attached by the structure shown in FIG.

That is, a pair of cutouts 7a, 7a are formed at a plurality of positions spaced apart in the length direction of the wiring board 7 so that the side edges on both sides face each other and are cut inward. .. A pair of hook-shaped engaging claws 9, 9 are formed facing each other in the width direction at a plurality of positions spaced apart in the lengthwise direction of the light-shielding member 6a of the light-shielding member 6. The gap between the tips of the engaging claws 9 and 9 is set to be smaller than the width of the wiring board 7 and larger than the interval between the cutouts 7a and 7a. It is set larger than the width of the substrate 7. Further, a through hole 10 is formed in the wiring board 7, and a screw hole 11 is formed in the light shielding portion 6a corresponding to the through hole 10.

Then, the portion of the power distribution board 7 sandwiched between the cutouts 7a, 7a is inserted into the gap between the base ends of the engaging claws 9, 9 through the gap between the tips of the engaging claws 9, 9, and then the wiring is performed. Wiring in which the cutouts 7a, 7a are not formed by removing the portion sandwiched between the cutouts 7a, 7a in the power distribution board 7 by shifting the board 7 in the longitudinal direction from the gap between the base ends of the engaging claws 9,9. The part of the substrate 7 is located in the gap between the base ends of the engaging claws 9, 9.

As a result, the wiring board 7 is pressed by the engaging claws 9 in both the width direction and the thickness direction. At this time, the through hole 10 of the wiring board 7 is aligned with the screw hole 11 of the light shielding part 6a, and the screw 12 is tightened by passing the screw 12 through both holes 10, 11. Thereby, the wiring board 7 can be attached.

Further, the wiring portion of the wiring board 7 can be connected to the power source by the following configuration. That is, when the photoconductor unit is attached to the main body of the electrophotographic apparatus, the pair of metal pieces 13 and 13 provided on the end portion of the wiring board 7 are attached to the case of the electrophotographic apparatus as shown in FIG. The pair of metal springs 15, 15 provided on the side wall of the eggplant body 14 are contacted.

A description will be added. A pair of metal bars 15, 15 are attached to face each other in an insertion hole 16 formed in the side wall of the apparatus body 14. The pair of metal springs 15 and 15 are connected to a DC power source. When mounting the photoconductor unit on the device body 14 and attaching the drum wiring board 7 to the light-shielding portion 6a of the light-shielding member 6, the pair of metal pieces 13, 13 are inserted into the insertion holes 16 of the device body 14, It contacts a pair of metal springs 15, 15 provided on 16. As a result, each chip-type light emitting diode 8 mounted on the wiring board 7 is connected to the DC power source through the wiring portion, the pair of metal pieces 13, 13 and the pair of metal springs 15, 15. When the photoconductor unit is detached from the main body 14, the metal pieces 13 and 13 come out of the insertion holes 16 and come off from the metal springs 15 and 15, and the chip type light emitting diode 8 of the wiring board 7 is turned into the direct current. Disconnected from power.

In this way, the wiring substrate 7 is attached to the surface of the light-shielding portion 6a of the light-shielding member 6 facing the photosensitive drum 1, with the chip-type light-emitting diodes 8 facing the surface of the photosensitive drum 2. Be done. As a result, the light-shielding portion 6a of the light-shielding member 6 is located behind the chip-type light-emitting diode 8 mounted on the substrate 7 and shields the light emitted from the chip-type light-emitting diode 8, and the light-shielding portion 6b serves as the chip. The chip-shaped light-emitting diode 8 is located on the front side with respect to the light-emitting diode 8 to block the light emitted from the chip-shaped light-emitting diode 8.

The tip of the light-shielding portion 6b of the light-shielding member 6 is as close as possible to the surface of the photosensitive drum 1, and the light of the chip-type light emitting diode does not reach the surface of the photosensitive drum 2 charged by the charging device 4. To do so.

The charging device 4 has a trough-shaped case 17 having a length corresponding to the length of the photosensitive drum 2, and a wire stretched inside the case 17 along the axial direction. Shaped discharge electrode 18. The charging device 4 is located above the photoconductor drum 2 and adjacent to the charge removal device 3 in front of the charge removal device 3 in the direction of rotation of the photoconductor drum so that the open portion of the case 17 faces the surface of the photoconductor drum 2. The case 17 is arranged along the axial direction of the photosensitive drum 2, and both ends of the case 17 are supported and fixed to members (not shown) provided in the unit frame 1.

The light-shielding portion 6b of the light-shielding member 6 of the static eliminator 3 is in contact with and fixed to the outer surface of the side wall of the case 17 facing the static eliminator 3 by an adhesive.

The cleaning device 5 is provided in a toner receiving portion 19 provided in the unit frame 1 on the side of the periphery of the photosensitive drum 2. That is, a cleaning blade 20 which comes into contact with the surface of the photosensitive drum 2 is attached to the upper portion of the toner receiving portion 19 of the unit frame 1 through the blade arm 21 and the toner receiving portion. Inside the 19, a toner discharge screw 22 is provided along the axial direction of the photosensitive drum 2. The photoconductor unit having such a configuration is attached to the apparatus body 14 of the electrophotographic recording apparatus. The electrophotographic recording apparatus main body is provided with an exposing device, a developing device, and a transfer device (not shown) around the photoconductor drum 2 of the photoconductor unit along the photoconductor drum rotation direction.

An outline of the image recording process by the photoconductor unit will be described.

The photosensitive drum 2 rotates counterclockwise as shown in FIG. First, in the charging device 4 provided in the photoconductor unit, corona discharge is performed by the discharge electrode 18. The surface of the photoconductor drum 2 is charged. Next, an original image is exposed by an exposure device provided in the main body of the electrophotographic apparatus to form an electrostatic latent image on the surface of the photosensitive drum 2. Then, a toner is attached to the surface of the photosensitive drum 2 by a developing device provided in the main body of the electrophotographic apparatus to form a toner image. Next, the toner image on the surface of the photosensitive drum 2 is transferred onto the recording paper by the transfer device provided in the main body of the electrophotographic apparatus.

Next, in the cleaning device 5 provided in the photosensitive member unit, the cleaning blade 20 scrapes off the toner remaining on the surface of the photosensitive drum 2 after the transfer. The scraped toner is received by the toner receiving portion 19 provided on the unit frame 1, and is discharged from the receiving portion 19 by the rotating screw 22. After the cleaning is completed, the electric charge remaining on the surface of the photoconductor drum 2 is removed by the charge removing device 3.

Next, the operation of the static eliminator 3 will be described.

A plurality of light emitting diodes 8 provided on the substrate 7 are energized to emit light. Light emitted from the chip type light emitting diode 8 travels toward the surface of the photoconductor drum 1 corresponding to the static eliminator 3 and is applied to the surface of the photoconductor drum 2. When the light of the chip type light emitting diode 8 reaches, the electric charge remaining on the surface of the photosensitive drum 2 is removed. In this case, since the white paint is applied to the chip-type light emitting diode mounting surface of the wiring board 7, the light emitted from the chip-type light emitting diode 8 is applied to the chip-type light emitting diode of the wiring board 7. It can be used for irradiation on the surface of the photoconductor drum 2 by reflecting it on the mounting surface, improving the light emission efficiency of the chip type light emitting diode 8 to the drum surface, and the number of chip type light emitting diodes 8 used. Can be kept low.

The photoconductor unit of the electrophotographic apparatus in this embodiment has the following effects. In the static eliminator 3, a chip-type light emitting diode 8 is used as a static elimination light source. Since this chip-type light emitting diode 8 can be surface-mounted on the wiring board, one surface of the wiring board 7 has a surface. It is implemented. For this reason, it is not necessary to provide a connecting portion with a lead wire for connecting the chip type light emitting diode 8 to the power source on the side surface of the wiring board 7 opposite to the chip type light emitting diode mounting surface. .. Therefore, a space for providing a connecting portion with a lead wire for connecting the chip type light emitting diode 8 to a power source is provided on the side of the wiring board 7 opposite to the chip type light emitting diode mounting surface. It is not necessary to secure a space, and the unit frame 1 can be downsized by the space.

On the side surface of the wiring board 7 opposite to the chip light emitting diode mounting surface, it is necessary to provide a connection portion with a lead wire for connecting the chip light emitting diode 8 to a power source. Since the wiring board 7 can be mounted by directly contacting the mounting member, which is the light shielding member 6 in this embodiment, the wiring board 7 can be mounted stably with sufficient strength. It is possible to precisely irradiate the surface of the photoconductor drum 2 with light by the dot 8.

The wiring board 7 is attached to the attachment member attached to the charging device 4, that is, the light shielding member 6 in this embodiment. Therefore, the position of the chip type light emitting diode 8 with respect to the charging device 4 can be accurately and easily adjusted. As a result, as shown in FIG. 5, the chip type light emitting diode 8 is provided at a position where the light emitted from the light emitting diode 8 is not applied to the surface of the photosensitive drum 2 charged by the charging device 4. Can be easily realized. FIG. 6 shows a case where the chip-type light emitting diode 8 is located at a position where the light emitted from the light emitting diode 8 is not applied to the surface of the photosensitive drum 2 charged by the charging device 4.

In order to attach the wiring board 7 to the light-shielding member 6, one screw is used and the other portions are engaged and supported. The reason for adopting this configuration is that since the wiring board 7 can extend in the lengthwise direction with this support, the wiring board 7 thermally expands in the lengthwise direction due to the heat generated by the light emission of the chip-type light emitting diode 8. This is because it is possible to suppress the occurrence of unreasonable bending or deformation by allowing the expansion of the wiring board 7 to escape in the lengthwise direction when the above occurs.

On the other hand, when the wiring board 7 is screwed at a plurality of positions, the wiring board 7 cannot be elongated in the lengthwise direction, and the wiring is generated due to the heat generated by the light emission of the chip-type light emitting diode 8. When the board 7 thermally expands in the length direction, the expansion of the wiring board 7 cannot be escaped in the length direction, and the wiring board 7 may be unnaturally bent or deformed.

[0050]

[Effect of the device]

 As described above, according to the photoconductor unit in the electrophotographic apparatus of the present invention, since the chip-type light emitting diode is directly mounted on the wiring board on which the wiring portion is formed, the lead wire on the back side of the wiring board No wiring is required. Therefore, the static eliminator can be downsized. In addition, the wiring board can be directly attached to the mounting member for stable mounting. Furthermore, by attaching the mounting member with the wiring board directly to the charging device, the position of the light emitting diode with respect to the charging device can be easily adjusted, and the light of the light emitting diode can be accurately reflected on the surface of the photosensitive drum. Can be irradiated.

[Brief description of drawings]

FIG. 1 is a sectional view showing a photoconductor unit according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a static eliminator and a charging device of the photoconductor unit in the embodiment.

FIG. 3 is a perspective view showing a wiring board and a light shielding member of the static eliminator in the embodiment.

FIG. 4 is a diagram showing an electrical connection between a wiring board and a power source of the static eliminator in the embodiment.

FIG. 5 is a diagram showing the relationship between the light and the charging device when the light from the light emitting diode in the charge eliminating device is applied to the photosensitive drum.

FIG. 6 is a diagram showing the relationship between the light and the charging device when the light from the light emitting diode in the charge eliminating device is applied to the photosensitive drum.

[Explanation of symbols]

2 ... Photosensitive drum, 3 ... Static eliminator, 4 ... Charging device, 7 ...
Wiring board, 8 ... Chip type light emitting diode.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Satoshi Kata, Satoshi Kata 1-chome, 3-chome, Asahigaoka, Hino, Tokyo Toshiba Corporation Hino Plant (72) Jiro Fukasawa, 1014 Miyahara-cho, Kofu-shi, Yamanashi Yamanashi Electronics Co., Ltd. (72) Inventor Seiichi Koizumi 1014 Miyahara-cho, Kofu-shi, Yamanashi Yamanashi Electronics Industry Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A photoconductor, a charging device for charging the photoconductor, and a static eliminator for removing residual charges on the photoconductor. The static eliminator comprises a chip type light emitting diode and the chip type light emitting diode. A photoconductor unit for an electrophotographic apparatus, comprising: a wiring board on which a light emitting diode is surface-mounted; and a mounting member which is mounted on the charging device and is mounted by abutting the wiring board.