JPH058870A - Sheet feeding device - Google Patents

Abstract

PURPOSE:To provide a cassette with a two-stage cassette function by dividing a conventional large cassette into two-stages of an upper and a lower stage to form an integral twostage cassette, and disposing a sheet feed roller at a lower stage part in a specified position from the conveyance roller of a space on the sheet feed side. CONSTITUTION:A conventional large cassette 10 is divided into two stages of upper and lower stages to form an integral two-stage cassette, and a sheet feed roller 25 at a lower stage part is disposed in a specified position from a conveyance roller 4 of a space on the sheet feed side. As a result, a cassette is provided with the function of a two-stage cassette without increasing the size of a device, and a large cassette (capable of loading approximately 500 sheets) is also mounted, and various needs regarding a sheet can be satisfied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device applied to an image forming apparatus such as a copying machine or a printer.

[0002]

2. Description of the Related Art In recent years, user demands for image forming apparatuses such as printers have been diversified, and the development of image forming apparatuses has been remarkable. In particular, in paper cassettes for loading paper, a wide variety of paper sizes, various types, and various forms of paper are used, and in terms of quantity, a small amount such as a cover letter is required, and laser printers with high-speed performance are also available. As described above, there are some which require a large capacity of 250 to almost 500 sheets. From the above viewpoints, at present, for a small amount but a large number of sheets, a sheet feeding device equipped with a two-stage cassette and two-stage sheet feeding rollers, and for using a large amount of sheets, about 500 sheets are required. Paper feeders that can be loaded with large-sized cassettes have been put into practical use, and are responding to various demands.

[0003]

FIG. 4 is a schematic view of a main part of a sheet feeding device to which a conventional two-stage cassette is applied. An upper cassette 61 and a lower cassette 71 capable of stacking approximately 250 sheets are mounted in the cassette mounting portion 60. In the upper cassette 61, sheets are stacked on the paper rotating plate 62, and the paper rotating plate 62 is urged upward by being supported by the spring 63, and fed by the sheet feeding roller 65 one by one from the top. The sheet is conveyed on the conveying path 81 by the conveying rollers 64 and sent to the process section. In the lower cassette 71, sheets are similarly stacked on the paper rotation plate 72, and the paper rotation plate 72 is supported upward by a spring 73 and is urged upward, and the paper is fed one by one from the top of the paper by the paper feed roller 75. Be paid out. The sheet is conveyed on the conveying paths 80 and 81 by the conveying roller 74 and sent to the process section.

However, in the above-mentioned sheet feeding device, a sheet feeding roller for feeding the sheets stacked in the lower cassette must be disposed between the upper cassette and the lower cassette, so that the size of the device can be reduced. Is impossible,
There has been a problem that the main body of a printer or the like to which the paper feeding device is applied also becomes large.

Further, in the case of the cassette of the paper feeding device as described above, when a large number of images are formed, since there is a paper feeding roller, a large cassette for 500 sheets cannot be mounted, and the upper cassette and the lower cassette are not installed. Since the cassettes are loaded separately, the operability is extremely poor.

An object of the present invention is to provide a sheet feeding device which allows a cassette to have a function of a two-stage cassette without increasing the size of the device and which can mount and feed a large-sized cassette (where approximately 500 sheets can be stacked). To do.

[0007]

According to the present invention, a large cassette capable of stacking a large amount of sheets, a cassette mounting portion for mounting the large cassette, and a cassette mounted in the cassette mounting portion are stacked. In a sheet feeding device including a sheet feeding roller that feeds sheets one by one from the top of the sheet, and a conveying roller that conveys the sheet fed from the sheet feeding roller to a process unit, the large cassette includes an upper stage unit and a lower stage unit. And a lower sheet feeding roller that feeds the sheets stacked in the lower section is the same as the distance from the conveying roller to the sheet feeding roller on the sheet feeding side of the upper section. It is characterized in that they are provided at positions separated by a distance.

[0008]

In the sheet feeding device according to the present invention, the large cassette is divided into two stages, the upper stage portion and the lower stage portion, and the sheet feeding roller for the lower stage is provided inside the upper stage portion. There is no need to provide a lower feed roller. Further, since the position of the lower sheet feeding roller is the same as the distance from the feeding roller of the sheet feeding device main body to the sheet feeding roller arranged in the main body, the sheet feeding / conveying is smoothly performed.

Further, in this paper feeding apparatus, a large cassette divided into two stages and a large cassette having substantially the same outer shape can be mounted, so that even a small amount of various kinds of paper can be loaded.
A large amount of paper can also be fed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic configuration diagram of the vicinity of a cassette mounting portion of a paper feeding device according to an embodiment of the present invention.

The cassette 10 is composed of an upper part 11 and a lower part 12, and is mounted on the cassette mounting part 1. A paper feed roller 3, a transport roller 4, and a manual paper feed port 5 are arranged above the cassette mounting portion 1 of the paper feed device main body. Upper part 11
Sheets are stacked on the rotary plate 21, and the rotary plate 21 is supported by a spring 22 and urged upward.

A lower feed roller 25 for feeding the sheets stacked on the lower portion is disposed in the space (left side in the drawing) on the paper feed side of the rotary plate 21 and the spring 22. The lower feed roller 25 is located at the same distance as the feed roller 3 from the transport roller 4. The lower plate 12 is provided with a rotary plate 23 and a spring 24 at a position suitable for the position of the lower paper feed roller 25, and the paper reaches the conveyance roller 4 through the conveyance path 6.

FIG. 2 is a schematic view of the cassette 10 of the paper feeding device, showing a state in which sheets are stacked.
The upper part 11 and the lower part 12 are opened and closed as shown.

The cassette may be opened and closed by other methods. For example, the upper portion 11 can be slid to take in and out the lower sheet.

When it is desired to use a large amount of paper, a large cassette capable of loading about 500 sheets can be mounted in the cassette mounting portion. FIG. 3 shows a state in which a large cassette is mounted in the cassette mounting portion of the paper feeding device.

Further, various variations can be considered by changing the capacity of the upper and lower sheets.

[0017]

As described above, according to the present invention, the conventional large-sized cassette is divided into two to form an integrated two-stage cassette, and the lower-stage sheet feeding roller is used for the upper-stage sheet feeding. By arranging at a fixed position from the conveying roller in the side space, it is not necessary to dispose the lower sheet feeding roller for the cassette on the sheet feeding apparatus main body side, and without enlarging the apparatus,
We were able to acquire the function of the two-stage cassette. In addition, the two-stage cassette can be slidable or opened / closed up and down to easily load paper, and since the outer shape of the two-stage cassette is the same as the conventional large cassette, the cassette loading section can be shared and a large amount of paper can be stored. It is possible to meet various demands of users, such as when it is required for printing, and when a small amount of different types of paper such as a cover letter is required. Therefore, it is possible to save space and improve operability and serviceability.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram in the vicinity of a cassette mounting portion of a paper feeding device that is an embodiment of the present invention.

FIG. 2 is a schematic view of a cassette of the paper feeding device, showing a state in which sheets are stacked.

FIG. 3 is a diagram illustrating a state in which a large cassette is mounted in a cassette mounting portion of the paper feeding device.

FIG. 4 is a schematic diagram of a main part of a sheet feeding device to which a conventional two-stage cassette is applied.

[Explanation of symbols]

 1 cassette mounting part 3 paper feed roller 4 transport roller 10 cassette 11 upper stage 12 lower stage 25 lower stage paper feeding roller

Claims (1)

Claim: What is claimed is: 1. A large cassette capable of stacking a large amount of paper, a cassette mounting portion for mounting the large cassette, and a sheet mounted in the cassette mounted in the cassette mounting portion. In a sheet feeding device including a sheet feeding roller that feeds out sheets one by one from the top, and a conveying roller that conveys the sheet fed out from the sheet feeding roller to a process unit, the large cassette includes an upper stage unit and a lower stage unit. The lower-stage paper feed roller that feeds the sheets stacked in the lower-stage part is separated from the upper-stage part on the paper-feed side of the upper-stage part, and is separated by the same distance from the transport roller to the paper-feed roller. A paper feeding device characterized by being provided at a position.