JPH0264657A - image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a process unit that integrally includes a photoreceptor drum and a process means arranged around the drum, and that is detachable from a main device. The present invention relates to an image forming apparatus having:

[Prior Art] Copying machines and printers using electrophotography require maintenance work such as replacing photosensitive drums, cleaning chargers, and disposing of waste toner when used for long periods of time.

In recent years, as a method to simplify the maintenance work and make it possible for general coaters to do so, multiple combinations of process means such as a photoreceptor drum, corona discharger, static eliminator, and developer have been combined into a unit, and this unit has been replaced with a new one. A method of replacement is being taken.

[Problems to be Solved by the Invention] However, in the method of unitizing each process means as described above, a contact is required for applying voltage to each process means from the main device, and the process unit is connected to the main device. In other words, the conventional method had the problem of causing contact failure when attaching and detaching the
Because the contacts were bonded and the process unit was fixed to the main unit at the same time, due to minute dimensional errors, the process unit was fixed to the main unit without sufficient contact pressure being applied to the contacts, causing the process to fail. If normal voltage is not applied to the unit and good print quality cannot be obtained,
Alternatively, even if sufficient contact pressure is obtained, there is a problem that the process unit is not completely fixed to the main device.

Therefore, in order to solve these conventional problems, the present invention has the following features:
When the process unit is attached to and removed from the main device, the contact points of each process means obtain sufficient contact pressure to ensure secure connection, and the process unit is securely fixed to the main device in an image forming apparatus. The purpose is to provide.

[Means for Solving the Problems 1] In order to solve the above problems, the present invention includes a photosensitive drum and a process means arranged around the drum, which are detachably attached to the main unit. An image forming apparatus having a process unit is characterized in that an elastic member such as a compression spring is interposed at a contact point for applying a voltage to each process means from the main unit.

Further, the present invention is characterized in that, when the process unit is attached to the main body device, the process unit is fixed to the main body device after the contacts are first joined.

[Function] According to the above mechanism of the present invention, by interposing an elastic member such as a compression spring in the contact, the contact can be moved in the direction of attachment and detachment of the process unit, and even if there is a minute dimensional error, Both the bonding of the contacts and the fixing of the process unit to the main device are performed reliably.

Furthermore, by fixing the process unit to the main unit with the contacts securely connected, the contacts can obtain a sufficiently high contact pressure, making it possible to apply a stable voltage.

〔Example〕

FIG. 1 is a side view of a blinking device using an electrophotographic method to which an embodiment of the present invention is applied.

The photosensitive drum 1 is supported rotatably in the direction of the arrow. Around this drum l, a corona discharger 2,
Process means such as an exposure device 3, a developing device 4, a transfer corona discharge device 5, a cleaning device 6, and a static eliminator 7 are provided.

The photosensitive drum 1, corona discharger 2, cleaning device 6, and static eliminator 7 are integrally supported by a frame 8 as a process unit 20.

The transfer material supplied from the supply tray 9 is first conveyed to the transfer section, and after the transfer is completed, it is sent to the fixing device 10 where it is fixed.
It is sent out from the discharge port via the discharge roller 11. Note that when the paper path is formed in the direction of gravity as shown by the dotted line, the paper is inserted between the transfer corona discharger 5 and the drum 1 by the roller 101, and then the paper is removed. It may be bent so that the leading end of the drum hits the paper guide and becomes concave on the drum side. If you do this, the toner-applied surface on the drum 1 side will become dirty.

FIG. 2 shows the printer main body and the process unit 2.
FIG.

When the process unit 20 is attached to or removed from the main body of the printer with an opening/closing door 22 provided at the front of the printer being opened, the process unit 20 is guided and supported by a guide 21 provided within the main body of the printer. When installed, a lock lever 24 provided inside the printer main body locks the bearings 23 installed on both sides of the photosensitive drum 1, and the process unit 20 is fixed within the printer main body.

FIG. 3 shows the process unit.

When the process unit 20 is attached to or removed from the printer main body, the side bottom portions A and B of the process unit 20 are guided and supported by guides 21 fixed to the main body. Further, a contact 26 for applying a voltage to each process means from the main unit is fixed at one end of the process unit.

Further, a drum drive gear 25 is fitted with a gear on the main unit side to transmit the driving force of the main unit to the photosensitive drum.

Here, FIG. 4 shows an embodiment of the above-mentioned contact structure of the present invention.

A metal electrode shaft 27 whose head has a plate-like structure is held in a contact holder 29 by an electrode bearing 28, and the electrode bearing 28 is connected to an electrode cover 30 which has a groove-like structure inside.
It is embedded in the contact holder 29 by the contact holder 29. In addition, a conductive electrode spring 31 connects the head of the electrode shaft 27 and the electrode bearing 28.
The electrode shaft 27 is supported by the electrode bearing 28 by an E-type stop shaft 32 or the like. As a result, the metal electrode shaft 27 becomes movable in the direction indicated by the arrow C when another contact 33 moves in the direction indicated by the arrow C and comes into contact with the electrode shaft 27.

FIG. 5 is a diagram showing a state in which the electrode shaft 27 is moved in the direction of the arrow. When the contact 33 is fixed in this state, strong contact pressure is obtained between the electrode shaft 27 and the contact 33 due to the elastic force of the electrode spring 31.

FIG. 6 is a diagram showing in detail a mechanism for attaching and detaching the main body device and the process unit 20 using the above-mentioned contacts 34.

The contact 34 using the above-described structure is fixed to the main device so that the electrode shaft 27 embedded in the contact 34 is movable in the mounting direction E of the process unit 20. Further, the lock lever 24 is pivotally attached to the main unit by a lock lever shaft 35.

Now, when the process unit 20 moves in the direction of arrow E during installation, the process unit bearing 23 rotates the lock lever 24 around the lock lever shaft 35. At the moment when the process unit side contact 26 contacts the main device side contact 34, the lock lever 24 is rotated by the process unit bearing 23 as shown in FIG. It is not fixed securely. The process unit 20 further moves in the E direction, and as shown in FIG. 5, the process unit side contact 26 is in a state where the metal shaft 27 embedded in the main device contact 34 is fully pushed in the direction of the arrow. At this time, as shown in Fig. 8, the process unit bearing 2
0 acts on the lock lever spring 36 (fits into the lock lever 24 by elastic force).

By interposing an elastic member such as a compression spring in the contact in this manner, both the contact and the attachment of the process unit to the main apparatus are reliably performed. Furthermore, the contact pressure of the contact point increases due to the elastic force of an elastic member such as a compression spring, making it possible to apply a stable voltage.

[Effect of the invention 1 According to the invention as described above, the photoreceptor drum and
In an image forming apparatus that integrally includes process means arranged around the drum and has a process unit that is removable from the main device, compression is applied to the contact point for applying voltage from the main device to each process means. The structure allows the contacts to move in the direction of attachment and detachment of the process unit using an elastic member such as a spring, and the process unit is fixed to the main body of the device after the contacts are fully bonded. Since the unit is securely attached to the main unit and the contact pressure of the contacts is sufficiently high, it is possible to apply a stable voltage and obtain good print quality in printers using electrophotography. This has the effect of making it possible.

[Brief explanation of the drawing]

FIG. 1 is a side view of a blinking device using an electrophotographic method to which an embodiment of the present invention is applied. FIG. 2 is a side view showing a mechanism for attaching and detaching the printer main body and the process unit. FIG. 3 is a perspective view of the process unit. FIG. 4 is a sectional view showing one embodiment of the contact structure of the present invention. FIG. 5 is a sectional view showing the state of connection of the contacts when the process unit is attached to the main device. FIG. 6 is a side view showing in detail the mechanism for attaching the process unit to the main device. FIG. 7 is a diagram showing a state in which the process unit is fixed to the main body when the contacts are in contact. FIG. 8 is a diagram showing a state in which the process unit is completely fixed to the main device. Photoreceptor drum process unit Process unit lock lever - First embodiment of the contact of the present invention Applicant: Seiko Epson Co., Ltd. Agent Patent attorney: Kizobe Suzuki (and one other person) Figure 2 Figure 3 Figure 4 Ken Figure 5 Official Figure 7

Claims (2)

[Claims] (1) In an image forming apparatus that integrally includes a photosensitive drum and a process means arranged around the drum, and has a process unit that is removable from the main device, voltage is applied to each process means from the main device. An image forming apparatus characterized in that an elastic member such as a compression spring is interposed at a contact point for applying a pressure. (2) An image forming apparatus having a mechanism in which the process unit is fixed to the main body after the contacts are first connected when the process unit is attached to the main body.