JPS62201468A - Copying machine - Google Patents

Abstract

PURPOSE:To suppress toner dispersion by providing a copying machine with a transfer room formed under the lower area of a photosensitive body in a housing and a recording paper carrier penetrated into the housing through a gap between the photosensitive body and the transfer room. CONSTITUTION:The transfer room 24 is positioned on the lower area of the photosensitive drum 21 and the recording paper carrier 27 is arranged close to the drum 21 so as to be penetrated into the housing 26. Thereby, the upper side of the recording paper carrier 27 is connected to a carry-in port 26a formed on the housing 26 and the lower side of the carrier 27 is connected to a carry- out port 26b formed on the housing 26. Recording paper is inserted into the housing 26 from the lower area of a developing device 23 along the carrier 27, and after transferring a toner image to the recording paper, carried from the housing 26 to the lower area of a cleaning device 25. The carry-in port 26a is arranged on a position, i.e. position adjacent to the drum 21, properly higher than the carry-out port 26b. Consequently, toner dispersion can be suppressed.

Description

[Detailed Description of the Invention] 3. Day 1. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine that is small and lightweight, and has a copying machine main body and a process unit that is detachable from the copying machine main body.

(Prior art) Recently, electrophotographic copying machines have been subject to deterioration due to use.
Alternatively, a copying machine has been developed in which a photoreceptor, a developing device, etc., which wear out with use, are integrated and configured to be detachable from the main body of the copying machine, thereby making it easy to replace consumables and the like. for example,
JP-A-59-61850 discloses a process unit that integrates a photoreceptor, a charging device, a developing device, and a cleaning device. The process unit is.

It does not include a transfer device, and the transfer device is attached to the main body of the copying machine. The lower part of the alternating knit is formed with the recording paper transport path formed by the gap between the transfer device attached to the main body of the copying machine and the photoreceptor housed in the unit as the boundary.

In such a process unit, when the process unit is installed in a copying machine main body, the surface of the photoreceptor and the transfer device must be opposed to each other via the recording paper conveyance path. On the other hand, when the process unit is removed from the copying machine main body, the photoconductor is placed inside the process unit housing in order to protect the surface of the photoconductor or to prevent the toner inside the process unit from scattering outside. It is necessary to close the process unit in the "J closed state" so that the process unit can be stored in the "J" closed state.
In the process unit disclosed in the 1850 publication, a special drum cover is provided to cover the photoreceptor, and when installed in the main body of the copying machine, the cover is opened to expose the surface of the photoreceptor and face the transfer device. Conversely, when the unit is removed from the main body of the copying machine, the surface of the photoreceptor is covered with this cover. Such a drum cover requires a complicated mechanism because it can be opened and closed in a narrow space.

Also, the drum cover can be opened easily.

A user of the copying machine may accidentally touch the surface of the photoreceptor. When the drum cover is opened, toner may be scattered around.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems.The purpose of the present invention is to provide a simple structure in which the photoreceptor moves outward when detached from the main body of the copying machine. It is an object of the present invention to provide a copying machine in which there is no risk of a user accidentally touching the surface of the recording paper (therefore, there is no risk of degrading the quality of the copied image). To provide a copying machine in which a toner image on a photoreceptor can be reliably guided to a photoreceptor, a toner image on the photoreceptor can be reliably transferred onto a recording paper, and jamming or the like does not occur.

(Means for Solving the Problems) The present invention includes a copying machine main body to which a transfer device is attached, and a process unit that is removably attached to the copying machine main body, and the process unit is fixed in the housing. a photoconductor, a charging device, a developing device, and a cleaning device, a transfer chamber formed in a region below the photoconductor in the housing, and a recording paper conveyance that passes through the housing between the photoconductor and the transfer chamber. a guide member capable of opening and closing an inlet and/or an outlet of the recording paper transport path; a transfer device insertion opening provided in the housing for inserting the transfer device into the transfer chamber; and the opening. and a sealing member that can be opened and closed, thereby achieving the above object.

(Example) Examples of the present invention will be described below.

As shown in FIGS. 1 and 2, the copying machine of the present invention has two
For example, there is an electrophotographic copying machine body 10 and a process unit 20. The copying machine main body 10 is.

The upper half 16 and the lower half 17 are rotatably supported by a pivot 19 with an upstream section 13a and a downstream section 13b of the recording paper transport path as boundaries. The process unit 20 is slid and attached to the upper half 16 from the side.

The process unit 20 includes a photoreceptor drum 21 as a photoreceptor rotatably disposed in the center of a housing 26.
．． Charging device 22. Developing device 23. and cleaning 2
5, which are integrally fixed to the housing 26. The charging device 22 is located above the photosensitive drum 21. The developing device 23 is disposed downstream of the charging device 22 in the rotational direction of the photosensitive drum 21 . The cleaning device 25 is disposed upstream of the charging device 22 in the rotational direction of the photoreceptor drum 21 . A sulin l-26c is provided on the upper surface of the housing 26. The Surin l-26C
is located between the charging device 22 and the developing device 23.

A transfer chamber 24 is formed in the lower part of the housing 26 . The transfer chamber 24 is located below the photosensitive drum 21. In the vicinity of the photosensitive drum 21 of the transfer chamber 24.

A recording paper conveyance path 27 is formed to penetrate the housing 26 . Therefore, the upstream side of the recording paper conveyance path 27 is connected to an inlet 26a formed in the housing 26, and the downstream side of the recording paper conveyance path 27 is connected to an outlet 26b formed in the housing 26. The recording paper is inserted into the housing 26 from the lower area of the developing device 23 along the recording paper conveyance path 27, and after receiving a toner image there, it is passed from the housing 26 to the cleaning device 23.
transported towards the lower area. In order for the recording paper carried into the housing 26 from outside the housing 26 through the carry-in port 26a to have a toner image transferred thereon, it is smoothly carried out of the housing 26 from the carry-in port 26b. It is preferable that the outlet 26b be provided at a position appropriately higher than the outlet 26b (a position close to the photoreceptor drum 21).

An introduction guide member 28 is provided at the entrance 26a. Furthermore, a guide member 29 is provided at the outlet 26b. The introduction guide member 28 has an introduction guide plate 28a and a support shaft 28b of the introduction guide plate 28a, as shown in FIGS. 3 and 4. The introduction guide plate 28
a is integrally attached to a support shaft 28b, and rotatably supported by the housing 26 by the support shaft 28b. The introduction guide plate 28a opens and closes the entrance 26a by its rotation. A coil spring 28d is fitted onto the side of the support shaft 28b. The coil spring 28d is.

One end is locked to the introduction guide plate 28a, and the other end is locked to a suitable fixing part (for example, the side of the transfer chamber 24), and the introduction guide plate 28a is urged to close the entrance 26a. ing.

One side of the support shaft 28b is connected to the inner wall 26 of the housing 26.
It passes through x. A central portion of a sliding contact portion 28c is fixed to an end surface of a support shaft 28b that passes through an inner wall 26x of the housing 26 and is located between the outer wall 26y and the outer wall 26y.

The sliding contact portion 28c is formed in a spiral shape with only 1/4 circumference. This is because the support shaft 28b (therefore the temporary introduction guide 28
This is because a) is stopped at a position rotated approximately 1/4 turn. The sliding contact portion 28c is inclined such that, for example, when the introduction guide plate 28a closes the entrance 26a, the distal end thereof is located downward, and the proximal end thereof is located upward.

The sliding contact portion 28C can come into contact with the tip of the press rod 10a fixed to the copying machine main body 10 when the process unit 1-20 is mounted on the copying machine main body 10. The tip of the pressing rod 10a abuts, for example, at a position eccentric to the side from the center of the sliding contact portion 28c. The process unit 20 is connected to the copying machine main body 1
When sliding it from the side to attach it to 0, the sliding contact part 2
8c comes into contact with the tip of the pressing rod 10a. Then, when the process unit 20 is further slid into the copying machine main body 10, the press rod 10a presses the sliding contact portion 28c. As a result, the tip of the pressing rod 10a applies a force in the direction of rotating the sliding contact portion 28c in the circumferential direction (toward the front), so the sliding contact portion 28C rotates against the biasing force of the coil spring 28d. . When the process unit 20 is completely attached to the copying machine main body 10, the sliding contact portion 28c is smaller than 90 degrees.
It stops in an inclined state rotated by an angle of about 0 to 80 degrees.

As a result, the introduction guide plate 28a opens the carry-in port 26a, and the rotated tip of the introduction guide plate 28a in the recording paper transport path 27 approaches the photoreceptor drum 21 in an inclined state and stops. When the process unit 20 is removed from the copying machine main body 10, the sliding portion 28c is no longer pressed by the press rod 10a, and the four large guide plates 28a are rotated by the coil spring 28d to close the loading port 26a.

In addition, in order to ensure that the sliding contact portion 28c rotates as the pressing rod 10a rotates, the sliding contact portion 28C that the pressing rod 10a contacts is
A groove may be provided in the circumferential direction at the surface position of the press rod 10a, and the tip of the press rod 10a may be engaged with the groove.

Further, the tip of the pressing rod 10a may be configured to have a hemispherical shape so that the pressing rod 10a and the sliding contact portion 28c can surely slide.
Alternatively, a rotatable ball may be provided at the tip of the pressing rod 10a.

Furthermore, as shown in FIGS. 5 and 6, the support shaft 28
A protrusion is provided on the side of the tip b, and the support shaft 2 is engaged with the protrusion.
A configuration may also be adopted in which a rotation guide 10b for rotating the rotation guide 8b is provided.

The introduction guide member 29 provided on the downstream side of the recording paper conveyance path 27 also has a similar introduction guide plate 29a, and when the process unit 20 is separated from the copying machine main body 10.

The outlet guide plate 29a closes the outlet 26b, and opens the outlet 26b when the process unit 20 is attached to the copying machine main body 10.

The lead-out guide plate 29a with the outlet 26b opened has a leading end in the recording paper conveyance path 27 facing the photoreceptor drum 29.
It will come to a tilted position and stop at a position close to .

The lifespan of the photosensitive drum 21 and the charging device 22 in the process unit 20 is approximately equal to the period required to consume the amount of toner stored in the developing device 23. Similarly, the capacity of the waste toner tank in the cleaning device 25 is such that it can accommodate the waste toner generated within the above period.

The lower surface of the transfer chamber 24 formed in the lower part of the housing 26 is formed with an opening 24a for inserting a transfer device, which will be described later. The opening 24a connects the inside of the transfer chamber 24 and the housing 2.
6 and communicates with the outside. The opening 24a is.

The size is such that a transfer device can be inserted for one day.

The opening 24a has one, for example, two sealing members 24b.

It can be opened and closed at 24b. Each seal member 2
The base end portions of 4b and 24b are fixed to opposing peripheral edges of the opening 24a in a single-supported state, respectively. The tips of each sealing member 24b and 24b are as follows.

They overlap at the center of the opening 24a. The sealing member 24b is made of a material 1 having light-shielding properties and flexibility.
For example, a plastic film or the like is used.

Upper half 1 of the copying machine main body 10 rotating around a pivot 19
6, the process unit 20 can be attached to it as described above. A sliding document table 11 is disposed above the upper half-rest 16. The document table 11 is.

It can slide in a direction perpendicular to the axis of the photoreceptor drum 21 mounted thereon. An optical system 12 is provided below the document table 11 . The optical system 12 images an image of a document placed on the document table 11 as the document table 11 moves.

The surface of the photosensitive drum 21 in the process unit 20 is exposed through the slit 26c of the housing 26.

A transfer device 18 is fixedly installed at a position facing the photosensitive drum 21 on the lower half 17 of the copying machine main body 10 .

When the upper half 16 and lower half 17 of the copying machine main body 10 are connected, the transfer device 18 is a process unit/l.
-20 enters the transfer chamber 24 while pushing open the seal members 24b and 24b of the opening 24a, and each seal member 24b and 24b comes into contact with the side surface of the transfer device 18. Therefore, the transfer device 18 and the opening 24a
The gap between the opening 24 and the opening 24 is closed by each sealing member 24b.
There is no possibility that external dust or the like will enter the transfer chamber 24 from the space a.

What are the upper half 16 and lower half 17 of the copying machine main body 10?

The recording paper is separated by an upstream section 13a and a downstream section 13b of the conveyance path. When the upper half 16 and lower half 17 of the copying machine main body 10 are connected, the upstream portion 1 of these conveyance paths
3a and the downstream portion 13b are the inlet 26a and the outlet 2 of the housing 26 of the process unit 20, respectively.
Connects to 6b. As a result, the upstream section 1 of the recording paper conveyance path
3a, the recording paper conveyance path 27 and the downstream portion 13b of the recording paper conveyance path communicate with each other. Therefore, the recording paper in the paper holder 14 of the copying machine main body 10 passes from the upstream part 13a of the transport path, passes through the recording paper transport path 27 of the transfer chamber 24, and passes through the downstream part 13b of the transport path. It can be discharged onto the tray 15. During this time, the transfer chamber 24 of the housing 26
The toner image is transferred onto the recording paper. This transferred toner image is fixed onto the recording paper by a fixing device 13c provided at the downstream portion 13b of the feeding path.

How to attach the process unit 20 to the main body IO of the copying machine.

This is done as follows. First, the upper half 16 of the copying machine main body 10 is rotated upward and separated from the lower half 17. In this state, the process unit 20 is attached to the upper half-rest 16 by sliding it from the side. As a result, as described above, the introduction guide plate 28a and the extraction guide plate 29
a is rotated into the housing 26 and passes through the recording paper conveyance path 27.
The loading inlet 26a and the unloading outlet 26b are respectively opened. Then, the introduction guide plate 28a and the extraction guide plate 29
The tip a rotates into the housing 26 and stops in an inclined state where the tip approaches the photoreceptor drum 21 .

Next, this upper half body 16 is rotated downward and connected to the lower half body 17. In this case, the sealing members 24b, 24b that close the transfer chamber 24 of the process unit 20 are attached to the transfer device 1 attached to the lower half 17 of the copying machine main body 10.
8 to open the opening 24a.

The transfer device 18 is inserted into the transfer chamber 24 while slidingly contacting each of the seal members 24b, 24b. And upper half holiday 16
When the lower half body 17 and the lower half body 17 are connected, the transfer device 18 becomes.

It faces a predetermined position of the photosensitive drum 21 across the recording paper conveyance path 27 .

The copying operation of this copying machine is similar to that of a conventional electrophotographic copying machine, and is as follows.

The surface of the photosensitive drum 21 is uniformly charged by the charging device 22 in the process unit 1-20. Next, the image of the original placed on the original table 11 is exposed by the optical system 12, and an electrostatic latent image is formed on the surface of the photoreceptor drum 21. The electrostatic latent image is developed with toner by the developing device 23. On the other hand, the recording paper passes through the upstream portion 13a of the conveyance path and is introduced into the recording paper conveyance path 27 of the process unit 20. At this time, the recording paper is guided by the introduction guide plate 28a toward the photoreceptor drum 21, and is brought into reliable contact with the photoreceptor drum 21. The toner image on the photosensitive drum 21 is transferred onto recording paper by a transfer device 24. The recording paper on which the toner image has been transferred is guided by the guide plate 29a and is reliably carried out of the housing 26 from the outlet 26b.

The toner image is then sent to the fixing device 13c through the downstream portion 13b of the vCt feeding path, where the toner image is fixed onto the recording paper. The recording paper with the toner image fixed thereon is discharged onto the tray 15. When the toner image is transferred to the recording paper, the photosensitive drum 21 is cleaned by a cleaning device 25 to remove residual toner from the surface thereof.

The life spans of the photosensitive drum 21 and the charging device 22 in the process unit 20 are set to be approximately equal.

Amount of toner in the developing device 23 and cleaning device 25
The amount of discharged toner inside is also set to correspond to the above-mentioned lifespan. Therefore, when the photosensitive drum 21 and the like reach their service life limit, the upper half 16 of the copying machine main body 10 is rotated upward.

At this time, the process unit 20.

The tip ends of the seal members 24b, 24b are in an initial overlapping state due to their flexibility, and close the opening 24a of the housing 26. And process unit 1-2
0 is slid in the axial direction of the photoreceptor drum 21 and removed from the upper half 16. Process unit 2
0 is removed from the copier main body IO.

The introduction guide plate 28a and the extraction guide plate 29a rotate to close the carry-in port 26a and the carry-out port 26b, respectively. Then, a new process unit 20 is attached to the upper half 16. The process unit 20 removed from the upper half 16 of the copying machine main body 10 is inserted into the recording paper inlet 2.
6a, the outlet 26b, and the opening 24a are all closed.

The copying machine of the present invention can also be applied to a copying machine whose main body 10 cannot be separated into an upper half 16 and a lower half 17. For a copying machine main body that cannot be separated into an upper half and a lower half, the process unit is attached to and removed from the copying machine main body by sliding in a direction perpendicular to the recording paper conveyance path in the copying machine main body. Figures 7 to 9 are.

This process unit 20'' shows a process unit 20' of the present invention that can be attached to and detached from such a copying machine main body.
An opening 24a' for inserting the transfer device is provided on one side of the transfer chamber 24'' in the sliding direction, which is formed in the area below the photoreceptor drum 21° in the housing 26'. 24a' includes sealing members 24b' and 24b made of the same material as in the previous embodiment.

are respectively supported on opposing peripheral edges of the opening 24a. The tips of each sealing member 24b° and 24b′ overlap at the center of the opening 24a°.

The opening 24a'' is closed. On the inner surface of the transfer chamber 24° facing the opening 24a', there is a locking portion 18 of the transfer device 18'.
An engaging portion 24d° that can be engaged with the “b” (described later) is provided.

The transfer device 18' has a support member 18 at 10° of the main body of the copying machine.
8'. The support member 18a' supports one end of the transfer device 18'' in the longitudinal direction.A locking portion 18b' is provided at the other end of the transfer device 1B' in the longitudinal direction.
is formed. The locking portion 18b'' can engage with the engaging portion 24d° within the transfer chamber 24°. Due to their engagement,
The process unit 20' is fixed at a predetermined position relative to the main body 10 of the copying machine. The other configurations are the same as those of the previous embodiment, so the explanation will be omitted.

The process unit 1-20' is attached to the main body of the copying machine in the following manner. The entire process unit 20' is slid into the copying machine main body 10° so that the locking portion 18b' of the transfer device 18' is inserted through the opening 24a° of the housing 26'. As a result, the sealing member 24b'' covering the opening 24a is pushed open by the locking portion 18b'', and the transfer device 18 is inserted into the transfer chamber 24. At this time, the sealing member 24b.

and 24b° due to its own flexibility transfer device 1
21.The person guide plate 28a and the lead-out guide plate 29a also rotate in the same manner as in the previous embodiment, and the temporary introduction guide 28a and the lead-out guide plate 2
9a opens the IIm person hole 26a and the discharge port 26b, respectively, and its rotated tip approaches the photoreceptor drum 21 in an inclined state. And the transfer device 18
The locking part 18a° of ゛ is the transfer chamber 24゛ The engaging part 2 on the inner surface
4b°, the process unit 20
" is attached to the copying machine main body 10' at a predetermined position.

Note that the transfer chamber 24 of such a process unit 20°
A guide member may be provided for guiding the transfer device 18° to a predetermined position.

(Effects of the Invention) As described above, in the copying machine of the present invention, even when the process unit is removed from the copying machine main body, the photoreceptor is covered by the recording paper conveyance path and the transfer chamber, so that it is not exposed to the outside. There is no risk of it happening. At this time, the transfer chamber is closed by the seal member, and the inlet and outlet of the recording paper conveyance path are closed by the guide member, so there is no fear that the housing photoreceptor will be exposed. There is no risk of toner scattering around.

Furthermore, by using such a process unit, in addition to replacing the process unit when it reaches the end of its service life, it is also possible to replace the process unit with a process unit that is capable of developing with color toner, and it is possible to easily perform color one-to-one processing.

4. Figure 1 is a longitudinal cross-sectional view of the copying machine of the present invention, and Figure 2 is a longitudinal cross-sectional view of the copying machine body with the upper half turned upward.
3 and 4 are side views of main parts when the process unit is installed, FIGS. 5 and 6 are side views of main parts in another embodiment, and FIG. 7 is a process unit in another embodiment of the present invention. 8 is a sectional view thereof, and FIG. 9 is a sectional view taken along line IX-IX in FIG. 8.

1 (L 10"...copying machine body, 18.18'...
・Transfer device.

20, 20'...process unit, 21.21
'... Photosensitive drum, 22... Charging device, 23...
...Developing device, 24.24''...Transfer chamber, 24a,
24a' - opening, 24b, 24b'... sealing member, 25... cleaning device L 26.26'
...Housing, 27...Recording paper conveyance path, 28...
・Introduction guide member, 28a...Introduction guide plate, 29・
...Derivation guide member.

29a... Lead-out guide member.

that's all

Claims (1)

[Scope of Claims] 1. It has a copying machine main body to which a transfer device is attached, and a process unit that is removably attached to the copying machine main body, and the process unit includes a photoreceptor fixed in the housing, a charging an apparatus, a developing device, and a cleaning device; a transfer chamber formed in an area below the photoconductor in the housing; a recording paper conveyance path passing through the housing and passing between the photoconductor and the transfer chamber; and the recording paper. a guide member capable of opening and closing an inlet and/or an outlet of a conveyance path; a transfer device insertion opening provided in the housing for inserting the transfer device into the transfer chamber; and a seal member capable of opening and closing the opening. A copying machine comprising: and.