JP2002020043A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively provide an image forming device that is small, easy to use and capable of double-sided recording. SOLUTION: The image forming device typically has a structure wherein it has an image forming means 5 for recording an image on a recording medium S and a stacking unit 2 for stacking and storing the recording medium S, the stacking unit 2 is mounted for withdrawal from a device body 1, and a feed path 14 for feeding the recording medium S is defined in the bottom of the stacking unit 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus for forming an image on a recording medium, and more particularly, to a conveyance path of the recording medium.

[0002]

2. Description of the Related Art Various types of image forming apparatuses for recording an image on a recording medium have conventionally been provided for recording an image on both sides of the recording medium. Among them, an image is first recorded on the first surface of the recording medium by one image forming means, and the image is recorded on the second surface by reversing the recording medium after recording the image and conveying it again to the image forming means. Is recorded. In such a configuration, a mechanism for reversing the recording medium and a transport path for re-transporting the recording medium into one unit are often added to the image forming apparatus main body. In other words, the unit formed as a double-sided mechanism is configured to be externally attached to the image forming apparatus or incorporated in the image forming apparatus.

A conventional image forming apparatus will be described with reference to FIG. The image forming apparatus 100 shown in the figure has a stacking unit 101 for stacking and storing a recording medium at the bottom of the apparatus. After an image is formed on the recording medium fed from the image forming unit 102, the image is fixed by a fixing unit 103. When printing is performed on both sides, the printing medium is guided to the duplex unit 105, and when printing is completed on one side, the printing medium is discharged to the discharge stacking unit 104.

The double-sided unit 105 is disposed beside and below the image forming apparatus 100, and a recording medium having an image formed on the first surface is conveyed to a switchback unit 106. Then, when the rear end of the recording medium passes the switching branch point 107, the transport roller of the switchback unit 106 is driven in reverse, transported to the transport path 108 to form an image on the second surface, and re-transported to the image forming unit 102. Is done. In the switchback unit 106 or the transport path 108, the leading end or side end of the recording medium is
Skew correcting means is provided so as to be parallel to the image to be formed.

Thereafter, the recording medium passes through the stacking unit 101, is again conveyed to the image forming means 102, and after the image is formed on the second surface, passes through the fixing unit 103 and is discharged and stacked on the discharge stacking unit 104. You. As described above, conventionally, the portion related to the double-sided mechanism is configured as a dedicated unit separately from the image forming apparatus.

[0006]

However, in the above-mentioned prior art, since the portion relating to the double-sided mechanism is a dedicated unit, the size of the apparatus has been increased. That is, when the unit is located below the apparatus main body and is integrated, the overall size, particularly the height, is increased. Further, since the switchback unit is provided not in the apparatus main body but in the unit, the size of the apparatus in the transport direction is increased (in the apparatus shown in FIG. 3, the size is increased rearward). Therefore, the transport distance until image formation on the recording medium becomes longer, and the recording time becomes longer.

Also, the recording medium after the image formation on the first surface often has a curl-like habit, and the degree required for the conveyance performance in the image formation on the second surface is higher than that on the first surface. Also, the frequency of occurrence of paper jams during the conveyance is higher than that on the first surface. However, in the conventional configuration, it is necessary to secure a space in the apparatus main body or to draw out the transport unit to the outside of the apparatus for processing when removing the recording medium having a paper jam. was there.

[0008] Further, it is required that a recording medium in a paper jam state can be visually checked. In contrast, in the conventional example, a large switchback
A space for handling a paper jam is provided in the main body of the apparatus, or the paper path 106 or the transport path 108 is pulled out.

As a result, the entire apparatus becomes large and complicated, the workability against paper jams is poor, and the apparatus is expensive. Therefore, an object of the present invention is to provide an image forming apparatus which is small, easy to use, and capable of double-sided recording at low cost.

[0010]

In order to solve the above-mentioned problems, a typical configuration of an image forming apparatus according to the present invention includes image forming means for recording an image on a recording medium, and stacking and storing the recording medium. An image forming apparatus having a stacking unit, wherein the stacking unit is removably mounted outside the apparatus main body, wherein a conveyance path for conveying the recording medium is provided below the stacking unit. The retractable state refers to at least two states of a state located inside the main body and a state located outside the main body, and the state outside the main body includes a state completely removed from the apparatus main body.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present embodiment, and FIG. 2 is a cross-sectional view of a transport path according to the present embodiment.

The image forming apparatus according to the present embodiment is a printer adopting an electrophotographic system, and has a loading unit 2 for loading and storing a recording medium S below a main body 1 of the apparatus. The recording medium S stacked on the stacking unit 2 is sent out by the pickup roller 3, conveyed to the registration roller pair 4 in front of the image carrier 5 serving as an image forming unit, and is corrected on the image carrier 5 after skew is corrected. Is further conveyed in synchronization with the image.

The image carrier 5 is uniformly charged by the charging means 6 and then scanned with light beams by the optical means 7 to form an electrostatic latent image, and the developing means 8 forms a toner image. After transferring the toner image onto the conveyed recording medium S by the transfer unit 9, the fixing unit 10
Fix. In the case of single-sided recording, the sheet is discharged and stacked on a discharge stacking section 12 formed on the upper surface of the apparatus main body 1 by the discharging means 11.

When double-sided printing is performed, the transport direction of the discharging means 11 which is a reversing means is reversed when the trailing end of the recording medium S on which the image formation on the first side is completed has passed the switching branch point 13. The recording medium is conveyed to the conveyance path 14 with the front end and the rear end interchanged. Then, the recording medium S is sent again to the image carrier 5 through the re-feeding path 2a provided in the stacking unit 2, and after the image on the second surface is transferred by the transfer means 9 and fixed by the fixing means 10, Then, the sheet is discharged to the discharge stacking unit 12 by the discharge unit 11.

In general, a double-sided mechanism requires a switchback mechanism and a transport path.
By incorporating that function into the inside, only the transport path is required for the double-sided mechanism, and the size of the apparatus can be reduced.

Here, the transport path in the double-sided mechanism requires three main parts: a transport guide, a transport unit, and a skew correcting unit. In this embodiment, the transport path 14 is a path for re-transporting the inverted recording medium to the image carrier 5, and includes a bottom surface of the stacking unit 2 and a bottom plate 1 a of the apparatus main body 1.
(See FIG. 2).

The conveyance guide of the conveyance path 14 includes a conveyance guide 2b formed integrally with the loading unit 2 and a main body bottom plate 1a.
And a conveyance guide 1b formed in the same direction. The transport guide 1b on the apparatus main body side is made of a sheet metal as a bottom plate of the main body skeleton.

A skew feeding roller pair 15 is provided on the stacking unit 2 as a conveying means of the conveying path 14, and a reference abutment surface 16 is formed integrally with the stacking unit 2 as a skew correcting means. The skew feeding roller pair 15 has a slightly inclined conveying direction toward the reference abutting surface 16 in order to abut the side end of the recording medium S against the reference abutting surface 16. That is, the transport path 14 is a transport based on one side, and the transport path 14 is transported while abutting the reference end surface of the recording medium S against the reference abutting surface 16 so that the recording medium S is corrected so as to be parallel to an image formed. ing.

With the above-described configuration, the image forming apparatus can be increased in size, in particular, a double-sided mechanism can be provided without changing the height, and the conveying path can be shortened, so that the recording time can be shortened. it can. Further, by pulling out the stacking unit 2, the transport path 14 can be opened, and the recording medium in the paper jam state can be removed while visually observing, and the workability for the paper jam can be greatly improved.

In the above embodiment, the transport path 14
Is configured between the loading unit 2 and the bottom plate 1a. However, by providing the loading unit 2 with the same transport guide 1b provided on the bottom plate 1a, it is also possible to provide a pair of transport guides on the bottom surface of the loading unit 2. good. In this case, in the operation for the paper jam, after the loading unit 2 is pulled out from the apparatus main body 1, the transport path 14 can be opened by releasing one of the guides attached to the loading unit 2.

In the above embodiment, the skew feeding roller pair 15 as the conveying means and the reference abutting surface 16 as the skew correcting means are used.
Are provided in the loading unit 2, but the same effect can be obtained by providing them in the apparatus main body 1.

[0022]

As described above, in the image forming apparatus according to the present invention, double-sided recording can be performed without increasing the size of the apparatus main body, particularly without changing the height. Therefore, the transport path for the double-sided mechanism can be made shorter than before, and the recording time can be reduced and the reliability can be improved.

Further, since the conveying path of the double-sided mechanism can be opened by pulling out the conventional recording medium stacking unit, workability and reliability against paper jam can be improved with a simple configuration.

Further, the size of the apparatus is smaller than that of a conventional image forming apparatus having a double-sided mechanism, and the mechanism is simpler, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to the present invention.

FIG. 2 is a cross-sectional view of a transport path according to the present invention.

FIG. 3 is a diagram illustrating an example of an image forming apparatus according to a conventional example.

[Explanation of symbols]

 S ... recording medium 1 ... apparatus main body 1a ... bottom plate 1b ... transport guide 2 ... loading unit 2a ... re-feed path 2b ... transport guide 3 ... pickup roller 4 ... registration roller pair 5 ... image carrier 6 ... charging means 7 ... optical Means 8 Developing means 9 Transfer means 10 Fixing means 11 Discharge means 12 Discharge stacking section 13 Switching branch point 14 Transfer path 15 Diagonal roller pair 16 Reference abutment surface

Continued on front page F term (reference) 2H028 BA06 BA09 2H071 BA13 BA14 DA22 DA23 EA04 3F053 BA03 LA01 LB03 3F100 AA02 BA17 CA12 CA15 EA03 EA05 3F102 AA01 AB01 BA02 BB04 EA06

Claims (6)

[Claims] 1. An image forming apparatus comprising: an image forming unit configured to record an image on a recording medium; and a loading unit configured to load and store the recording medium, wherein the loading unit is removably mounted outside the apparatus main body. An image forming apparatus, wherein a transport path for transporting a recording medium is provided below the loading unit. 2. The image forming apparatus according to claim 1, further comprising: a reversing unit configured to reverse a conveying direction of the recording medium after recording the image, wherein a conveying path formed by a lower surface of the stacking unit is configured to transfer the inverted recording medium. The image forming apparatus according to claim 1, wherein the image forming apparatus is a conveyance path that re-conveys the image to the image forming unit. 3. A transport path for transporting the recording medium includes a lower surface of the loading unit and an apparatus main body, and the transport path surface is opened by retracting the loading unit out of the apparatus main body. The image forming apparatus according to claim 1, wherein: 4. A transport path for transporting the recording medium is constituted by a pair of transport guides provided below the loading unit, and one of the transport guides can be opened when the loading unit is detached from the apparatus main body. The image forming apparatus according to claim 1, wherein 5. A skew correcting means for correcting a skew of a recording medium is provided on the transport path.
The image forming apparatus as described in the above. 6. The image forming apparatus according to claim 4, wherein the skew correcting unit is a guide unit that regulates a side end of the recording medium, and is formed integrally with the stacking unit.