JPH02123066A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To prevent recording paper from being diagonally fed by constituting a device forming in the surface part of an engaging member a guide surface serving as the one part of a conveying surface. CONSTITUTION:A guide unit 21 provides on its conveying surface an engaging member 24 for disengageably fixing the guide unit 21 to a device main unit side. Further this engaging member 24 forms in its surface part a guide surface 241 serving as the one part of the conveying surface, and recording paper is prevented from diagonal feed by uniformly generating friction resistance of the recording paper when it is inserted through.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an electrophotographic apparatus that performs a predetermined image forming operation while conveying recording paper along a conveyance path, and particularly relates to an electrophotographic apparatus that performs a predetermined image forming operation while conveying recording paper along a conveyance path. The present invention relates to an electrophotographic apparatus in which at least a portion of a recording paper conveyance path leading to a recording paper transport path is configured to be openable.

``Prior Art'' In an electrophotographic apparatus, an upper main body and a lower main body can be separated and opened almost along a recording paper conveyance path from a recording paper feed section to an ejection section, which prevents jams occurring on the conveyance path. This is extremely advantageous in practice in order to facilitate processing or maintenance of various parts within the apparatus, and for this reason, many small electrophotographic apparatuses employ the split-body structure.

On the other hand, in so-called face-down electrophotographic devices, in order to automate page alignment and reduce the footprint of the device, the recording paper, which has been conveyed horizontally to the fixing position, is moved vertically along the side wall of the device. Many devices form a so-called horizontal J-shaped conveyance path in which the paper is reversed while changing its direction and delivered to a tray section formed on the top side of the device.If such a configuration is adopted, the fixing path near the direction change position is Many jams tend to occur on the downstream side of the means or the entrance side of the reversing paper discharge path.

For this reason, it is preferable that the vicinity of the direction change position be opened following the opening of the upper body, but for example, as shown in FIG. Since the radius is small, it is not possible to create a vehicle that integrally connects and opens all of the device side walls 2A-2B, which serve as guide bodies for the reversing paper discharge path C, to the upper main body A side, and as a result, it is impossible to create a vehicle that connects and opens all of the device side walls 2A-2B, which serve as guide bodies for the reversing sheet discharge path C, and as a result Even if the inlet side of the reversing paper ejection path C is not substantially opened, and on the other hand, if a pivot point is provided on the downstream side of the fixing device, the area near the redirection position will not be opened unless the dividing opening angle is made considerably large. This is difficult to adopt, not only from a safety standpoint but also because it requires a large rotation space.

For this reason, the present applicant has previously proposed the device side walls 2A-2B having a concave arc-shaped inner wall surface to form the reversing paper ejection path C, or a convex surface disposed facing the concave arc-shaped inner wall surface 25-28. All or part of the arcuate conveyance guide body 21 is positioned on the lower main body B or upper main body A side, and the one side member 21 forming the reversing sheet discharge path C separately from the main body split structure is placed on the apparatus main bodies A and B. Pivotally supported for free swinging.

An apparatus is proposed in which the inlet side of the reversing sheet discharge path C can be divided and opened by swinging the member 21.

(Japanese Patent Publication No. 82-187868, Patent Application No. 62-2441
No. 70) In addition, even in devices that do not have a main body split structure as described above, the inlet side of the reversing paper ejection path C and other parts of the recording paper conveyance path where jams are likely to occur can be made into split openable fingers. There are also configured devices.

"Problem to be Solved by the Invention" Now, in order to divide and open the reversing sheet discharge path C as described above, the apparatus side walls 2A-2B or the conveyance guide body 21 are simply pivotably supported on the apparatus main body. However, it is necessary to provide an engaging member for releasably fixing these guide bodies to the main body of the apparatus.

Generally, such an engaging member is attached to an area outside the paper ejection path C where it does not obstruct the insertion of the recording paper, but the reversing paper ejection path C is extremely narrow between the fixing means and the side wall of the apparatus. Since the reversing paper ejection path C is formed in a large space and over the entire area in the drum axial direction, other parts other than the recording paper transport path are extremely limited, and an engaging member is attached to that part. It is quite difficult to find enough space for this purpose, and the device inevitably becomes larger.

Furthermore, even if the above-mentioned extra space is secured, there is a heating element such as a fixing roller, a substrate, or a conduction system gear in the area outside of the reversing paper ejection path C, so there is no risk of contacting these. It is also quite difficult to configure the joining member to be operable.

It is an object of the present invention to eliminate the drawbacks of the prior art, and in particular to achieve miniaturization of the device and ease of operation of the engaging member, and to reverse the paper from the image fixing position in the reversing paper ejection path C. It is an object of the present invention to provide an electrophotographic apparatus that facilitates the handling of recording paper jams that occur near the entrance of a paper discharge path C.

``Means for Solving the Problems'' The present invention relates to an electrophotographic apparatus in which a guide body having a recording paper conveying surface is configured to be swingable with respect to the apparatus main body, and in particular, the present invention relates to an electrophotographic apparatus in which a guide body having a recording paper conveying surface is configured to be swingable with respect to the apparatus main body. The present invention relates to the arrangement and structure of the engaging member for fixing the device.

In this case, the guide body includes the side wall of the apparatus constituting the reversing sheet discharge path C, or a conveyance guide body (hereinafter collectively referred to as a guide body), or any guide body for dividing and opening a part of the recording paper conveyance path. including.

In the invention described in claim 1), the first feature is that the engaging member is provided on the conveying surface of the guide body, and the second feature is that the engaging member is provided on the surface of the guide body. A guide surface is formed on the transport surface, and the guide surface forms a part of the conveyance surface.

On the other hand, in the invention described in claim 2), at least a part of the conveyance surface of the guide body is configured to be exposed, and in particular, at least a portion of the engaging member, specifically an operating portion, is configured to be exposed to the surface of the guide body. It is characterized by being placed on an exposed portion of the conveying surface.

In this case, it is not necessary to form a guide surface on the surface of the engaging member as in the above invention, but it is necessary to form a guide surface on the surface of the engaging member, for example, to the extent that the insertion of the recording paper is not obstructed. It is sufficient that the guide body is located at least on the same plane as the conveying surface of the guide body or on the back side thereof.

In addition, in order to configure a part of the conveying surface of the guide body to be exposed,
This can be easily achieved by dividing the main body or configuring only the reversing conveyance path so that it can be divided and opened, but it is not limited to this.

"Operation" According to this technical means, in both the first invention and the second invention, the engaging member is not disposed in a limited narrow space outside the recording paper conveyance area, and the guide body is Since it is directly attached to the recording paper conveyance area, there is no need to secure a special space for attaching the engaging member, and as a result, the apparatus can be downsized.

Also, for the wide area of the recording paper conveyance surface of the guide body.

The arrangement of the engaging members not only improves operability, but also improves safety by eliminating the risk of contact with heating elements such as fixing rollers, substrates, transmission gears, etc. that are located outside the transport area. It also improves.

Furthermore, in any of the above inventions, since the engaging member is arranged so as not to obstruct the insertion of the recording paper, there is no obstacle to the recording paper conveying function of the guide body, and especially in the first invention, the engaging member is arranged so as not to obstruct the insertion of the recording paper. Since a guide surface is formed on the surface of the mating member and the guide surface forms a part of the conveying surface, the frictional resistance during insertion does not become uneven and skewing and other problems can be prevented. preferable.

In addition, in the invention of part 2, since the engaging member is disposed not in a recessed position but in an exposed portion of the guide conveyance surface, operability is greatly improved.

[Embodiment j] Hereinafter, preferred embodiments of the present invention will be described in detail by way of example with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, and relative arrangements of the components described in this example are not intended to limit the scope of this invention, but are merely illustrative examples. It's nothing more than that.

First, the schematic configuration of the main parts of a laser printer to which the present invention is applied will be explained based on the sectional view of FIG. 3. The upper body A consists of an upper body A and a lower body B that can be separated and opened, and the upper body A substantially hides an upper frame body 1 that supports various members described below in a fixed or removable manner and a space above the frame body 1. A drum unit 5 includes an optical scanning means, a developing unit (all not shown), a photosensitive drum 5a, a cleaning member 5b, a charger 50, etc., housed in the frame body 1.
is removably attached, and by the biasing force of a coil spring 6 interposed between the unit 5 and the frame body 1, the photosensitive drum 5a and the developing roller (not shown) are attached when the upper body A is split open.
When the upper body A is closed, the drum shaft 5d fits into the U-groove support 31 provided on the lower body B side, and can be positioned at a predetermined position by the biasing force of the coil/hook 6. It is configured.

Further, the upper cover unit 2 forms a concave arc-shaped upper paper discharge guide surface 25 forming a part of a paper discharge unit 20 (to be described later) on the inner surface side of the side wall 2A, and a concave inclined concave paper discharge guide surface 25 on the exit side of the paper discharge guide surface 25. A paper ejection tray portion 2a formed in this manner is provided.

- On the lower body B side, along the recording paper conveyance path, there is a paper feed roller, a registration roller (all not shown), a transfer device 11 arranged at a position facing the circumferential surface of the drum 58, and a lower frame. A conveyance guide 12 formed on the upper surface side of the body 1b, a pair of fixing rollers for thermally fixing an unfixed toner image, and a pair of paper discharge rollers 22 forming a part of a paper discharge unit 20 are incorporated on the downstream side of the fixing device 13. ing.

The paper ejection unit 20 includes a concave arc-shaped upper paper ejection guide surface 25 formed on the paper ejection side wall 2A on the upper main body A side;
The lower paper discharge guide surface 28 formed on the side wall 2B on the side of the lower main body B and the downstream side of the fixing device 13, and these guide surfaces 25.28
A bow-shaped sheet discharge guide body 21 is formed facing the frame wall 3 on the side of the lower main body B, and is rotatably supported by the frame wall 3 on the lower body B side. It consists of a pair of paper ejection rollers 22, 23 which are pivotably supported.

According to this configuration, after the toner image carried on the photosensitive drum 5a is transferred by the transfer device 11 while the recording paper is conveyed along the recording paper conveyance path.

The recording paper is inserted into the fixing device 13 via the conveyance guide 12 to fix the unfixed toner image, and then the recording paper on which the image has been fixed by the fixing device 13 is placed between the two paper discharge guide surfaces 25, 28 and the paper discharge guide body. 21, the paper is ejected to the top side of the apparatus by the rotation of a pair of paper ejection rollers 22 and 23 provided at an arbitrary location, and the paper is ejected onto the top cover 2. Paper can be discharged onto the tray portion 2a formed in the tray.

Next, the structure of the paper discharge guide body 21, which is the gist of the present invention, will be explained in detail based on FIGS. 1 and 2.

The paper discharge guide body 21 has both paper discharge guide surfaces 25.2.
Drive rollers 22 and 23 are rotatably supported on both upper and lower ends of the convex arc-shaped surface 211 facing the rollers 6, and ribs 212a are provided on the circumferential surface sandwiched between the drive rollers 22 and 23 in parallel along the conveyance direction. is formed to function as a conveying surface 212.

And the lower body B and the upper body A at the center of the conveyance surface 212.
A recess is formed with a rectangular cross section from the curved surface located above the boundary surface between the two toward the lower end, and an engaging member 24 that can be secured to the frame wall 3 on the lower main body B side is disposed in the recessed portion 213. Set up

The engagement member 24 includes an arcuate guide surface 241 that is the same as the conveying surface 212, an engagement portion 242 formed by bending the guide surface 241 in an inverted shape from the lower end side, and the guide surface 241 is provided with a rib 241a at the same position as the conveying surface 212 to prevent the recording paper from being skewed as much as possible.

The engagement portion 242 is rotatably supported on the concave wall of the guide body 21 via a rotating shaft 243 that protrudes laterally at the corner of the inverted-shaped portion. The engagement protrusion 244 provided at the lower end is connected to the key-shaped end 3a provided at the end of the frame wall 3.
The rotating shaft 2
43, the engaging member 24 can be positioned and fixed on the frame wall 3 side via the engaging protrusion 244.

According to this embodiment, when recording paper becomes jammed on the reversing paper ejection path C, the conveyance surface 212 of the guide body 21 is exposed by opening the upper main body A, making it possible to easily clear the jam. On the other hand, if the recording paper is jammed at the inlet side of the reversing paper ejection path C or the fixing device 13, the engaging member 24 can be removed by pressing the engaging member 24 against the elastic force of the spring member 245.
The guide body 21 is released from the frame wall 3 side through the frame wall 3 side, and the guide body 21 can be rotated upward. This opens the entrance side of the paper ejection path C and the downstream side of the fixing device 13, making it easy to remove jams. Can be processed.

In this case, the guide body 2 exposed by opening the upper body A
Since the operating portion (guide surface 241) of the engaging member 24 is located on the conveying surface 212 of the engaging member 24, the operation is easy.

FIGS. 4 and 5 show another embodiment in which the upper main body and the lower main body are not separated, and in particular, the side wall of the apparatus forming the reversing sheet discharge path C° is configured to be openable.

The paper ejection unit 30 includes a concave arc-shaped paper ejection guide surface 41 formed inside the apparatus side wall 40, and an arch-shaped paper ejection guide surface 51 formed on the frame wall on the apparatus main body 50 side facing the guide surface 41. A paper ejection path C' is formed between the paper ejection path C' and the image is fixed by the fixing device 13 by rotation of a pair of paper ejection rollers 81 and 82 rotatably supported on both upper and lower ends of the paper ejection path C°. The recording paper is configured such that it can be discharged onto a tray portion 52 formed on the upper surface side of the apparatus along the side wall 40 of the apparatus.

And the device side v40 where the paper ejection guide surface 41 is formed
is swingably supported on a fulcrum 42 provided on the lower end side, and has a rectangular recess in the center of the north end side of the device side wall 40, and an engagement member 80 is attached to the recess 43.

The engaging member 80 has a substantially horizontal "<" shape, and its lower end side is rotatably supported on the wall surface of the recessed portion 43, and the engaging protrusion 81 provided on the engaging member 60 is The wooden body 50 of the apparatus is configured to be able to be engaged with an engagement recess 53 provided at the end of the upper wall, and by pressing the engagement member 60 from above, the above-mentioned The engagement is configured to be releasable. Further, a conveying rib 83a is formed on the inner wall surface 63 side of the engaging member 60, which serves as a conveying surface, similar to the concave arc-shaped discharge guide surface 41 of the apparatus side wall 40.

According to this embodiment, when recording paper is jammed on the reversing paper discharge path C', by pressing the engaging member 60 from above, the engaging protrusion θ1 provided on the tip side and the engaging protrusion θ1 on the side of the first side of the device can be separated. When the engagement with the engagement recess 53 is released and the device side wall 40 is rotated in the direction of the arrow through the engagement member 80, the paper discharge path C' is opened, and the fulcrum of the device side wall 40 is Since it is provided on the paper path C° entrance side, it is possible to easily remove any jammed recording paper in the vicinity.

Furthermore, since the operating portion (upper surface) of the engagement member 60 is directly exposed to the outside on the Kinio side, the operation is easy.

[Effects of the Invention] As described above, according to the present invention, there is no need to secure a special space for attaching the engaging member, and as a result, the device can be made smaller and safety is improved.

Further, arranging the engaging member over a wide area of the recording paper conveyance surface of the guide body leads to improved operability and does not impede the recording paper conveyance function of the guide body in any way.

In particular, in the first aspect of the invention, a guide surface is formed on the surface of the engaging member, and the guide surface forms the negative part of the conveying surface, so that the frictional resistance during insertion is prevented from becoming uneven. It is possible to prevent skewing and other problems.

In addition, in the invention of part 2, since the engaging member is disposed not in a recessed position but in an exposed portion of the guide conveyance surface, operability is greatly improved.

It has various effects such as

[Brief explanation of the drawing]

1 to 3 show a laser printer according to an embodiment of the present invention, FIG. 3 is a cross-sectional view of the main parts thereof, and FIGS. 1 and 2 are cross-sectional views showing the structure of the main parts of a paper ejection unit. FIG. FIGS. 4 and 5 are a cross-sectional view and a perspective view showing the main structure of a paper discharge unit according to another embodiment of the present invention.

Claims (1)

[Scope of Claims] 1) In an electrophotographic apparatus in which a guide body having a recording paper conveying surface is configured to be swingable relative to the apparatus body, an engagement for releasably fixing the guide body to the apparatus body side is provided. An electronic device characterized in that a mating member is provided on the conveying surface of the guide body, a guide surface is formed on the surface of the engaging member, and the guide surface forms a part of the conveying surface. Photographic device 2) In an electrophotographic device in which a guide body having a recording paper conveyance surface is configured to be swingable with respect to the device main body, at least a part of the conveyance surface of the guide body is configured to be exposed, and the guide body is configured to be able to be exposed. An electrophotographic apparatus characterized in that at least a part of an engaging member for releasably fixing the engaging member to the apparatus main body side is located at an exposed portion of the guide conveyance surface 3) Surface of the engaging member Claim 2, wherein the side is located on the same plane as the conveying surface of the guide body or on the back side thereof.
4) The electrophotographic apparatus according to claim 1), wherein the guide body is a reversing guide body that guides the recording material after image fixation to the top side of the apparatus while reversing it.
or 2) the electrophotographic device described above;