JPH09319239A - Electrophotographic device and contact spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic device provided with a high-voltage power source connecting mechanism having simple constitution for a transfer roller. SOLUTION: A contact 23 is provided on a high-voltage power source board 15, and a contact spring 24 equipped with a coil spring part 24a and a ring contact part 24b is attached by an attaching case 25 so that it may be conducted to the contact 23 and the ring contact part 24b may be projected to the outside of the case, while a transfer spring 18 is conducted to the transfer roller 10 through a conductive bearing 17. Only by inserting the board 15 in a specified position, the ring contact part 24b of the contact spring 24 comes in contact with the transfer spring 18, and the contact 23 of the board 15 is conducted to the transfer roller 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus such as a laser beam printer, and more particularly to an electrophotographic apparatus having a simplified structure for connecting a high voltage power source to a transfer roller and a contact spring suitable for use therein.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic apparatus such as a laser beam printer, a high voltage is used for a charger for charging a photosensitive drum and a transfer roller for transferring a toner image on the photosensitive drum onto a recording paper. For this reason, a high-voltage power supply board is provided inside the device. As a component for connecting the high-voltage power supply from the high-voltage power supply base to the transfer roller, a contact provided so as to directly contact the transfer roller or to a conductive bearing supporting the transfer roller. A leaf spring for a vehicle and a harness for connecting the leaf spring and the high-voltage power supply board have been used.

[0003]

However, such a conventional structure requires the work of fixing the leaf spring by screwing or the like and the work of connecting the harness. Since these works are troublesome, the number of assembling steps is increased. There was a problem that it would cause cost increase. Further, since the leaf spring is higher in cost than the coil spring and the like, this also causes a cost increase.

The present invention has been made in view of the above problems, and is an electrophotographic apparatus provided with a high-voltage power supply connecting structure having a structure capable of easily performing an assembling work, and a plate suitable for use in the electrophotographic apparatus. An object of the present invention is to provide a contact spring which is cheaper than a spring and easy to mount.

[0005]

According to the present invention, in order to simplify the connection mechanism of a high voltage power source to a transfer roller, a high voltage power source substrate is provided with a contact and a contact spring which conducts to the contact.
When the high-voltage power supply board is set at a predetermined position in the main body of the apparatus, the contact spring comes into contact with a conductive member electrically connected to the transfer roller so as to be electrically connected. With this configuration, the harness conventionally used can be omitted, the high voltage power source can be connected to the transfer roller only by setting the high voltage power source substrate at a predetermined position, and the assembly work can be simplified and the cost can be reduced. .

Further, in order to provide a contact spring having a simple structure, the present invention provides a contact spring having a ring-shaped ring contact portion by raising one end of a coil spring at a right angle. In this way, the contact spring of the present invention can be manufactured at low cost because only a part of the ordinary coil spring is slightly processed, and in use,
Since it suffices that the ring contact portion is inserted into a mounting case having a space for accommodating the slit and the coil spring portion and the mounting case is mounted on a base or the like, the mounting work can be extremely easy.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The electrophotographic apparatus of the present invention is provided with a conductive member so as to be electrically conducted to a transfer roller provided at a predetermined position in the apparatus main body, while a high voltage power source board is provided with A contact for connecting a high-voltage power supply to the transfer roller is provided and a contact spring is provided so as to be electrically connected to the contact, and when the high-voltage power supply board is set at a predetermined position, the contact spring comes into contact with the conductive member. It is configured to conduct electricity.

According to the present invention, when the high-voltage power supply board is set at a predetermined position, the contact spring provided on the high-voltage power supply board is brought into contact with the conductive member which is electrically connected to the transfer roller to be electrically connected to the transfer roller. A high voltage power source can be connected, and the operation of connecting the high voltage power source to the transfer roller can be simplified.

A contact spring according to the present invention comprises a coil spring portion, a ring contact formed integrally with the coil spring portion at one end of the coil spring portion, and in a ring shape in a plane parallel to the axis of the coil spring portion. And a section. The contact spring of this configuration is such that the ring contact portion is inserted into a mounting case having a slit capable of protruding the ring contact portion and a space for accommodating the coil spring portion so that the ring contact portion protrudes from the slit, and By placing the end on the opposite side on the contact provided by fixing it to the base or the like, it can be easily attached to the contact provided on the base or the like in a conductive state, and the ring contact part is coiled. The spring force of the spring part pushes it against the contact of the other party to ensure reliable conduction. Moreover, the ring contact is moved by moving the ring contact relative to the other contact in the direction parallel to the ring contact. The parts can be brought into contact with or separated from each other without causing undesirable deformation.
The contact and release operations of the contact spring and the contact on the other side can be performed very easily.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments shown in the drawings will be described below. FIG. 1 is a schematic sectional view of an electrophotographic apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic perspective view showing the electrophotographic apparatus with an opening / closing section opened. 1 is an apparatus main body, 2 is an opening / closing part that can be opened and closed with respect to the apparatus main body 1, 3 is recording paper, 4 is a recording paper cassette,
Reference numeral 5 is a feed roller for feeding the recording paper 3 in the recording paper cassette, 6 is a feed roller for conveying the recording paper 3 further downstream,
Reference numeral 7 is a photosensitive drum, and 8 is a process cartridge including the photosensitive drum 7, which is internally provided with a charger, a developing device, a cleaner and the like. Reference numeral 9 is a laser scanning unit that exposes the photosensitive drum 7 according to recording information, 10 is a transfer roller that transfers the toner image on the photosensitive drum 7 onto the recording paper 3, 11 is a fixing roller, and 12 is a discharge roller.

Reference numeral 15 denotes a high-voltage power supply base for applying a high voltage to the charger in the process cartridge 8 and the transfer roller 10. A part of the high-voltage power supply base is located below the transfer roller 10 and is provided on the guide rail 16. It is movably held. Then, by sliding the high-voltage power supply board 15 along the guide rails 16, the high-voltage power supply board 15 can be set at a predetermined position in the apparatus main body 1.

FIG. 3 is a schematic perspective view showing a portion on which the high-voltage power supply board 15 is mounted, and FIGS. 4 (a) and 4 (b) are schematic cross-sectional views showing the high-voltage power supply connection portion for the transfer roller in different states, respectively. FIG. 4 is a sectional view taken along the line AA of FIG. A bearing 17 made of a conductive material is attached to the shaft 10a of the transfer roller 10, and an upper end of a transfer spring 18 made of a coil spring made of a conductive material is attached to a lower end of the bearing 17. There is. On the other hand, the transfer spring 18
The lower end of the cylindrical portion 20a formed on the support member 20.
It is seated in a cylindrical recess therein. The support member 20 is held by the apparatus body 1. Thus, the transfer roller 10 is pushed up by the transfer spring 18 and pressed against the photosensitive drum 7 (see FIG. 1), and the transfer spring 18 is electrically connected to the transfer roller 10 via the bearing 17. Become. In other words, the transfer spring 18 constitutes a conductive member provided so as to be electrically connected to the transfer roller.

A slit 21 extending parallel to the transfer roller 10 is formed at the bottom of the cylindrical portion 20a on which the transfer spring 18 is mounted, and a part of the transfer spring 18 is exposed.
On the other hand, the high-voltage power supply board 15 is provided with a contact 23 for connecting the high-voltage power supply to the transfer roller near one end thereof, and a contact spring 24 is arranged above the contact 23 so as to be electrically connected to the contact 23. It is mounted on the high-voltage power supply board 15 by the mounting case 25. As shown in FIGS. 6A, 6B, and 6C, the contact spring 24 includes a coil spring portion 24a made of a conductive material, and one end of the coil spring portion 24a integrated with the coil spring portion. And a ring contact portion 24b formed in a ring shape in a plane parallel to the axis of the coil spring portion.

3 to 5, the mounting case 25 is provided with claws 25a and 25b for mounting on the high-voltage power supply board 15.
The high voltage power supply board 15 can be attached and detached by the claws 25a and 25b. Further, the mounting case 25 has a cylindrical space 27 that accommodates the coil spring portion 24a of the contact spring 24, and a slit 28 that is formed at the upper end of the space 27 and that allows the ring contact portion 24b to project upward.
It has. This slit 28 is a mounting case 25.
Is attached to the high-voltage power supply board 15, the roller is formed parallel to the transfer roller 10. The dimensions and mounting positions of the contact spring 24 and the mounting case 25 are shown in FIG. 4A when the high-voltage power supply board 15 is inserted from the position shown in FIG. 4B to a predetermined position in the apparatus body 1. As described above, the ring contact portion 24b enters the slit 21 formed at the lower end of the cylindrical portion 20a of the support member 20, contacts the transfer spring 18 at that position, and is slightly depressed.

In FIG. 3, 30b is a ring contact portion at the tip of a contact spring for a contact formed on the lower surface of the process cartridge 8 (see FIG. 1). The contact spring having the ring contact portion 30b has the same structure as the contact spring 24, and the contact spring 2 is attached to the mounting case 25.
It is held in a structure similar to that of No. 4. However, the ring contact portion 30b is arranged in a direction orthogonal to the ring contact portion 24b, that is, in a direction orthogonal to the transfer roller 10. This is because the process cartridge 8 (see FIG. 1) is inserted in the direction orthogonal to the transfer roller 10 after the high-voltage power supply board 15 is set at a predetermined position and brought into contact with the ring contact portion 30b.

Next, the method of assembling the power supply connecting portion with respect to the transfer roller in the apparatus having the above structure will be described. The contact spring 24 is placed in the space 27 of the mounting case 25 and the ring contact portion 24b is projected from the slit 28 of the mounting case 25. With the contact spring set, the mounting case 25 is attached to the high-voltage power supply base 15 using the claws 25a and 25b. As a result, the contact spring 2
4 is attached to the high-voltage power supply board 15 in a state of being electrically connected to the contacts 23. Then, the high-voltage power supply board 15 is pushed into a predetermined position in the apparatus main body 1 along the guide rail 16 to a predetermined position. As a result, as shown in FIG. 4A, the ring contact portion 24b becomes the cylindrical portion 20a of the support member 20.
Enters into the slit 21 formed at the lower end of the contact hole, contacts the transfer spring 18 at that position, and is slightly pushed down. Further, at this time, the ring contact portion 24b moves in the ring-shaped surface direction and enters the slit 21, and the transfer spring 1
Since it is pushed down by 8, the ring contact portion 24b will not be unstablely deformed, and can be pushed down stably. Thus, the ring contact portion 24b at one end of the contact spring 24 is pressed against the transfer spring 18 by the spring force of the coil spring portion 24a, and the other end is pressed against the contact 23, so that reliable conduction is ensured. As described above, the power supply can be connected to the transfer roller by an extremely simple operation.

In the above embodiment, the ring contact portion 24b of the contact spring 24 is brought into contact with the transfer spring 18 for pressing the transfer roller 10 against the photosensitive drum 7, and the present invention has this structure. Not limited to the transfer spring 18, a suitable conductive member that is electrically connected to the transfer roller 10 may be provided, and the ring contact portion 24b may be brought into contact therewith. However, it is preferable to use the transfer spring 18 as a conductive member as in the illustrated embodiment, because the advantage of reducing the number of parts can be obtained. In the above embodiment, the high-voltage power supply board 15 is inserted along the guide rails 16 to set it at a predetermined position, but a mounting method other than insertion may be adopted.

[0018]

As described above, according to the present invention, the high-voltage power supply board is provided with the contacts and the contact springs connected thereto, and when the high-voltage power supply board is set at a predetermined position in the apparatus body, Since the contact spring contacts the conductive member that is electrically connected to the transfer roller and makes it conductive, the harness used in the past can be omitted, and the high voltage power supply for the transfer roller can be simply set at the predetermined position. It is possible to connect to each other, and it is possible to simplify the assembly work and reduce the cost.

Further, the contact spring of the present invention can be manufactured at an extremely low cost by constructing a ring-shaped ring contact portion by raising one end of the coil spring at a right angle to form a ring shape. When mounting, simply place it in a mounting case that has a slit that allows the ring contact part to project and a space that houses the coil spring part, and then mount the mounting case on a base etc. to mount it in place. It has the effect that the mounting work can be made extremely easy.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an electrophotographic apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing the electrophotographic apparatus shown in FIG. 1 with an opening / closing section open.

3 is a schematic perspective view showing a portion to which a high-voltage power supply board is attached in the electrophotographic apparatus shown in FIG.

4A and 4B are schematic perspective views showing a state in which a high voltage power source is connected to the transfer roller of the electrophotographic apparatus shown in FIG. 1, and FIG.
Is a schematic perspective view showing the state before connection

5 is a cross-sectional view taken along the line AA of FIG.

6 shows a contact spring used in the embodiment of FIG.
(A) is a schematic front view, (b) is a schematic side view, and (c) is a schematic plan view.

[Explanation of symbols]

 1 Device Main Body 2 Opening / Closing Part 3 Recording Paper 4 Recording Paper Cassette 5 Feed Roller 7 Photosensitive Drum 8 Process Cartridge 9 Laser Scan Unit 10 Transfer Roller 11 Fixing Roller 12 Ejection Roller 15 High Voltage Power Supply Base 16 Guide Rail 17 Bearing 18 Transfer Spring 20 Supporting Member 21 Slit 23 Contact 24 Contact Spring 24a Coil Spring 24b Ring Contact 25 Mounting Case 27 Space 28 Slit

Claims (2)

[Claims] 1. A transfer roller, a conductive member provided to be electrically connected to the transfer roller, a contact for connecting a high-voltage power source to the transfer roller, and a contact provided to the contact. An electrophotographic apparatus comprising a high-voltage power supply board having a contact spring, and the contact spring is brought into contact with the conductive member to conduct electricity when the high-voltage power supply board is set at a predetermined position. 2. A contact having a coil spring portion and a ring contact portion integrally formed with the coil spring portion at one end of the coil spring portion and formed in a ring shape in a plane parallel to the axis of the coil spring portion. Spring.