KR200233153Y1 - Paper pick-up device paper cassette - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs.

The present invention relates to a paper pick-up device of a paper cassette, and more particularly, to a paper pick-up device for maintaining a constant paper feed pressure regardless of the amount of paper loaded in the paper cassette.

I. The technical problem that the invention is trying to solve.

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper pick-up device of a paper feed cassette capable of maintaining a constant paper feed pressure regardless of the size and loading of paper.

All. The gist of the solution of the invention.

The present invention provides an image forming apparatus having a main body and a paper feed cassette for loading paper and mounted on the main body, wherein the drive motor is provided inside the main body to which the paper feed cassette is mounted and is engaged with a gear formed at one end thereof. A rotating roller shaft, a pickup roller provided on the roller shaft and having a space therein, and a pickup spring having one end fixed to the roller shaft and the other end supporting an inner surface of the pickup roller in the interior of the pickup roller. It is characterized by including the configuration.

la. Important uses of the devise.

The present invention is used for paper pickup of an image forming apparatus.

Description

Paper pickup device of paper cassette {PAPER PICK-UP DEVICE PAPER CASSETTE}

The present invention relates to a paper pick-up device of a paper cassette, and more particularly, to a paper pick-up device for maintaining a constant paper feed pressure regardless of the amount of paper loaded in the paper cassette.

Typically, image forming apparatuses such as laser beam printers and copiers are equipped with paper feed cassettes for loading paper. The paper feed cassette is divided into a standard cassette capable of loading only a single sheet of a predetermined standard and a universal cassette capable of loading various standard sheets according to the type of paper that can be loaded.

1 is a side schematic view showing a paper feed cassette according to an embodiment of the prior art, and FIG. 2 is a chart showing a change in paper feed pressure according to the amount of paper loaded in the paper feed cassette.

In the related art, as shown in FIG. 1, the paper feed cassette 100 includes a paper plate 20 rotatable about a cassette body 10, a hinge axis 25 extending from both sides of the inside of the cassette body 10, and a lower surface of the paper plate 20. And pressurizing springs 30 supported on the underside of the overfeed cassette 100, respectively. In addition, a pickup roller 70 which rotates about a roller axis and whose cross section is close to a half moon is provided inside the main body of the image forming apparatus to which the paper feed cassette 100 is mounted.

Looking at the process of picking up the paper 40 from the paper feed cassette 100 having the above configuration as follows. First, after loading an appropriate amount of paper 40 on the upper surface of the paper plate 20, and then mounting the paper feed cassette 100 in the main body of the image forming apparatus, the pickup roller 70 installed in the main body is positioned above the paper 40 loaded on the paper plate 20. do.

Subsequently, the paper 40 on the paper plate 20 is rubbed with the outer circumferential surface of the pickup roller 70 by the elastic force of the pressing spring 30 supporting the paper plate 20, and when the pickup roller 70 rotates, the friction force between the pickup roller 70 and the paper 40 is reduced. By this, the paper 40 is picked up inside the main body of the image forming apparatus.

On the other hand, in the paper feed cassette 100 and the pickup roller 70 as described above, maintaining a constant paper feed pressure is essential for the paper 40 loaded on the paper plate 20 to be smoothly picked up by the pickup roller 70 into the main body of the image forming apparatus. That is, even if the amount of paper loaded on the paper plate is changed as shown in FIG. 2A, a feeding failure such as heavy feeding or paper feeding does not occur when the paper feeding pressure on the paper is always constant.

The paper feeding pressure according to the conventional embodiment is determined by the elastic force of the pressing spring 30 installed on the bottom of the paper plate 20 and the size of the paper. The elastic force of the pressing spring 30 is fixed at the time of manufacture, so that b, c, and As in d, if the amount or size of paper loaded on the paper plate 20 changes, the paper feed pressure also changes. Therefore, when using only the pressure spring 30, the elastic value is determined at the beginning of the production as in the prior art, there was a problem that the feeding failure phenomenon occurs due to the change in the paper feed pressure according to the specification and the loading amount of the paper.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a paper pick-up apparatus of a paper feed cassette capable of maintaining a constant paper feed pressure regardless of the size and loading amount of paper.

In order to achieve the above object, the present invention provides an image forming apparatus having a main body and a paper feed cassette for loading paper and mounted on the main body, wherein the paper feed cassette is provided inside the main body to which the paper feed cassette is mounted, and is formed at one end. A roller shaft rotated by a drive motor meshed with a gear, a pickup roller provided on the roller shaft and having a space therein, one end of which is fixed to the roller shaft and the other end of the pickup roller It is characterized by comprising a pickup spring for supporting the inner surface.

1 is a side schematic view of a paper cassette according to an embodiment of the prior art,

2 is a table showing a change in paper feeding pressure according to the amount of paper loaded in the paper cassette;

3 is a block diagram showing a paper pick-up device of the paper feed cassette according to a preferred embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

62: roller shaft 64: shaft support

70: pickup roller 75: pickup spring

80: caller 100: paper feed cassette

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that the detailed description of the related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

3 is a block diagram showing a paper pick-up device of the paper feed cassette according to a preferred embodiment of the present invention.

As shown in FIG. 3, the paper feed cassette 100 includes a paper plate 20 rotatable about a cassette main body 10, a hinge shaft 25 extending from both sides of the inside of the cassette main body 10, and a lower surface of the paper plate 20 and a paper feeder. It consists of a pressurizing spring 30 each supported on the underside of the cassette 100. At this time, the elastic force of the pressure spring 30 is set based on the heaviest paper of the standard of the paper that can be loaded in the paper feed cassette 100.

In particular, a paper pick-up apparatus according to a feature of the present invention is a drive motor (not shown) engaged with a gear 60 installed inside a main body (not shown) of an image forming apparatus to which the paper feed cassette 100 is mounted and formed at one end thereof. A roller shaft 62 rotated by and supported by at least one shaft support 64, a pickup roller 70 installed on the roller shaft 62 and having a space therein, and one end of the roller shaft being fixed inside the pickup roller 70. It is fixed to 62 and the other end is composed of a pick-up spring 75 for supporting the inner surface of the pickup roller 70, and the collar 80 is formed on both sides of the pickup roller 70 of the roller shaft 62, each formed in a wheel shape.

Referring to the operation of the paper pick-up device of the paper feed cassette having the above configuration is as follows.

When the paper feed cassette 100 on which the paper 40 is loaded is mounted in the main body of the image forming apparatus, the surface of the pickup roller 70 in the main body and the upper surface of the paper 40 of the paper cassette 100 come into contact with each other. At this time, the surface of the pickup roller 70 is pressed toward the paper 40 by the pickup spring 75 installed inside the pickup roller, while the paper 40 loaded on the paper plate 20 is picked up by the pressure spring 30 installed on the bottom of the paper plate 20. Pressure on the side. Further, the caller 80 provided on both sides of the pickup roller 70 regulates the upper height of the loaded paper 40 by the radius R of the caller, thereby regulating the pressing force applied to the surface of the pickup roller 70 by the pressure spring 30 to a predetermined pressure or less. .

Therefore, when a small amount of paper is loaded in the paper plate 20 so that the upper height of the paper does not reach the bottom surface of the collar 80, a large amount of paper is loaded in the paper plate 20 so that the upper height of the paper is lower than the bottom of the collar 80. Even if the surface is touched, most of the feeding pressure for picking up the paper into the main body is provided from the pickup roller 70 with the pick-up spring 75, and the pressure by the pressure spring 30 provides the auxiliary pressing force to help pick up the paper on the pick-up roller 70. do.

As described above, the paper pick-up apparatus of the paper cassette according to the embodiment of the present invention always picks up paper at a constant feeding pressure of the pick-up roller regardless of the paper size and the loading amount, so that the paper pick-up device is smooth without any feeding failure such as feeding or misfeeding. There is an effect of feeding.

Claims (2)

An image forming apparatus comprising a main body and a paper feed cassette for loading paper and mounted on the main body, A roller shaft installed inside the main body to which the paper feed cassette is mounted and rotated by a drive motor engaged with a gear formed at one end thereof; A cylindrical pickup roller installed on the roller shaft and having a space therein; And a pickup spring having one end fixed to the roller shaft and the other end supporting an inner surface of the pickup roller in the pickup roller. The method of claim 1, wherein each installing Kohler (Collar) of the respective wheel shape on both sides of the roller-axis pick-up roller, a paper pick-up of a paper feed cassette device which is characterized in that the caller is regulated the height of the paper loaded in the paper cassette .