KR100433425B1 - Paper feeding apparatus for an image forming apparatus - Google Patents

Abstract

The present invention relates to a cassette type image forming apparatus feeder. The paper feeding device according to the present invention includes a paper feed cassette provided with a paper pressing plate for elastically supporting the loaded paper, a locking device which is installed at the bottom of the paper cassette, and fixes the paper pressure plate at the bottom, and the paper cassette is mounted. The release member which is installed on one side of the cassette mounting portion and opens the locking device, and which is installed on the ceiling of the cassette mounting portion, and which is pushed upward by the paper presser which is elastically returned when the locking device is released by the unlocking agent. It characterized in that it comprises a paper separation prevention member for preventing. The paper release preventing member is characterized in that it comprises a roller-shaped contact end in contact with the paper on the paper pressing plate, and a spring for elastically supporting the contact end. According to the invention as described above, the phenomenon that the loaded paper is separated by the elastic return force of the paper pressing plate generated when the paper feed cassette is attached to the cassette mounting portion is prevented by the paper release preventing member.

Description

Paper feeding apparatus for an image forming apparatus

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image on paper, and more particularly, to a paper feeding apparatus for feeding paper into an image forming unit of an image forming apparatus by a paper feed cassette.

An image forming apparatus is a device capable of forming a predetermined image on a paper. The image forming apparatus is a printer connected to a computer to print predetermined data, a copying machine for copying a predetermined document, and a facsimile for transmitting or receiving a predetermined document content to another fax machine. Say.

In general, such an image forming apparatus includes a sheet feeding apparatus for loading a sheet on which a predetermined image is to be formed and feeding the sheet to the image forming unit, and a sheet cassette method is widely used as the sheet feeding apparatus.

FIG. 1 shows a state in which a paper cassette is mounted on a cassette mounting portion of an image forming apparatus in a conventional paper cassette type sheet feeding apparatus.

Referring to FIG. 1, a paper feeding device includes a paper feeding cassette 10, a cassette mounting portion 20, and a pickup roller 30.

The paper feeding cassette 10 includes a paper pressing plate 11 for supporting the paper 1, one end of the paper pressing plate 11 is hinged and the other end is elastically supported by the spring 14. Therefore, the paper 1 loaded on the paper feed cassette 10 is elastically supported obliquely by the paper pressing plate 11. In addition, the paper feed cassette 10 includes a locking device 15 capable of fixing the paper pressing plate 11 to the bottom 13 of the paper cassette.

The cassette mounting unit 20 guides the entry / exit of the paper cassette 10, and the paper cassette 10 is fixed at a predetermined position so that the paper 1 loaded on the paper cassette 10 stably is an image forming unit (not shown). To be supplied). In addition, an unlocking device for releasing the locking device 15 of the paper feed cassette is provided on one inner side of the cassette mounting portion 20.

The pickup roller 30 is installed at a predetermined distance apart from the upper side of the paper feed cassette 10. The separation distance is such that the pickup roller 30 can come into contact with the upper surface of the paper presser plate 11 when the paper presser plate 11 inclines the paper 1. In addition, the pickup roller 30 has a shape consisting of a portion of a completely cylindrical shape in order to transfer the paper 1 to the image forming portion at regular intervals. Therefore, when the paper cassette 10 is mounted on the cassette mounting portion 20, a space corresponding to the radius of the pickup roller exists between the paper pressing plate 11 and the pickup roller 30 of the paper cassette.

The operation of the paper feeder of the image forming apparatus having the same structure as described above will be described with reference to FIGS. 1 and 2.

The user loads the paper 1 into the paper feed cassette 10. At this time, the user presses the paper presser plate 11 to the bottom 13 of the feeder cassette in order to facilitate the loading of the paper 1 and the mounting of the paper cassette 10, and the paper presser plate 11 is locked ( 15) to the bottom 13.

Then, the paper feed cassette 10 is fitted to the cassette mounting portion 20 of the image forming apparatus. The state of the paper feed cassette 10 during mounting is shown in FIG. At this time, the locking device 15 is released by the unlocking device while the paper feeding cassette 10 is inserted, and the paper presser plate 11 is inclined upward. Then, the pickup roller 30 is rotated to transfer the paper 1 loaded on the paper pressing plate 11 in the direction A in which the image forming unit is located to perform a predetermined image forming operation.

By the way, the paper feeder of the image forming apparatus having the above-described structure, when the paper cassette is attached to the cassette mounting portion, the locking device is released and the paper pressing plate is springed upward by the elastic force of the spring located below. Then, the paper stacked on the upper surface of the paper pressing plate is also subjected to an upward impact by the force. At this time, since there is a space between the pickup roller and the paper pressing plate, the paper shocked by the paper pressing plate is released. In particular, when there is little paper loaded on the paper pressing plate, there is a problem that the paper may completely deviate from the conveying path by the elastic return force of the paper pressing plate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is easy to load paper into a paper cassette and mount the paper cassette to the image forming machine, and by the elastic return force of the paper pressing plate to mount the paper cassette to the cassette mounting portion. It is an object of the present invention to provide a paper feeding apparatus of an image forming apparatus in which stacked sheets are not separated.

1 is a schematic diagram showing a paper feeding apparatus of a conventional image forming apparatus;

FIG. 2 is a view showing a state immediately before the paper pressing plate of the paper feed cassette mounted on the cassette mounting portion of the image forming apparatus of FIG. 1 is released;

3 is a schematic view showing a paper feeding apparatus of an image forming apparatus according to the present invention;

4 is a view showing a state immediately before the paper pressing plate of the paper feed cassette mounted on the cassette mounting portion of the image forming apparatus of FIG. 3 is released;

5 is a cross-sectional view illustrating a locking device of the paper feed cassette of FIG. 4.

* Description of the symbols for the main parts of the drawings *

One; Paper 10; Paper Feed Cassette

11; Paper press plate 13; Bottom plate

14; Spring 20; Cassette compartment

30; Pickup roller 40; lock

41; Clasp 42; Fixed end

43; Mobile body 44; spring

50; Paper separation preventing member 51; Children roller

In order to achieve the above object, the paper feeding apparatus of the image forming apparatus according to the present invention, a paper feed cassette having a paper pressure plate for supporting the loaded paper inclined elastically, and is installed on the bottom of the paper cassette, the paper pressure plate is the bottom A locking device to be secured to be positioned at an inner side of the cassette and a cassette mounting part on which the paper feed cassette is mounted, and an unlocking member for opening the locking device, and a ceiling mounted on the cassette mounting part, and being elastic when the locking device is released by the unlocking part. And a paper release preventing member that prevents the paper from being pulled upward by the paper pressing plate returned.

Here, the paper release preventing member is preferably an elastic material capable of buffering the paper pressing plate that is elastically returned.

In addition, the paper release preventing member is characterized in that it comprises a contact end in contact with the paper on the paper pressure plate, and a spring for elastically supporting the contact end. Here, it is preferable that a contact end is a roller which rotates freely.

And, the paper separation prevention member is preferably provided between the unlocking member and the tip of the paper feed cassette.

In addition, the locking device includes a latch installed at the bottom of the paper presser plate, a movable body installed at the bottom of the paper cassette and having a fixed end to be latched, and a spring for elastically supporting the movable body, and when the paper presser is pushed downward, the latch is fixed. The paper pressing plate is fixed to the bottom of the paper cassette, and the latch is pushed out of the fixed end so that the paper pressing plate is inclined.

The unlocking member may be a protrusion formed at a position corresponding to an upper end of the movable body of the locking device on one side of the cassette mounting unit.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of a paper feeder of the image forming apparatus according to the present invention.

Referring to FIG. 3, the paper feeding apparatus according to the present invention includes a paper feeding cassette 10, a cassette mounting portion 20, a pickup roller 30, and a paper separation prevention member 50.

The paper feeding cassette 10 includes a paper pressing plate 11, the paper pressing plate 11 is hinged at one end thereof, and the other end is elastically supported by the spring 14. Therefore, the paper 1 loaded on the paper feed cassette 10 is elastically supported obliquely by the paper pressing plate 11. In addition, the paper feed cassette 10 includes a locking device capable of fixing the paper pressing plate 11 to the bottom 13 of the paper cassette.

One example of a locking device is shown in FIG. 4. Referring to the drawings, the locking device 40 has a clasp 41 protruding downward of the paper pressing plate 11 and a fixed end 42 which is installed on the bottom 13 of the paper feed cassette and catches the clasp 41. The moving body 43 and the spring 44 which elastically supports the moving body 43 laterally are included. The upper portion of the fixed end 42 is formed in an inclined surface so that the movable body 43 is moved laterally when the latch 41 is pressed downward. In addition, the bottom plate 13 of the paper feed cassette is provided with a stopper 46 for limiting the movement displacement of the movable body 43 by the spring 44.

The cassette mounting unit 20 is provided in the main body of the image forming machine, guides the entry / exit of the paper cassette 10, and the paper cassette 10 is fixed at a predetermined position so that the paper 1 loaded on the paper cassette 10 stably. Is supplied to an image forming unit (not shown).

In addition, an unlocking device for releasing the locking device 40 of the paper feed cassette is provided on one inner surface of the cassette mounting portion 20. In the present embodiment, the paper feeding cassette 10 is shaped into a projection which is shaped so that the upper end of the movable body 43 of the locking device can be pressed while being inserted into the cassette mounting portion 20.

The pickup roller 30 is installed to be spaced apart from the upper side of the paper cassette 10 by a predetermined distance, and the separation distance may contact the upper surface of the paper presser plate 11 when the paper presser plate 11 inclines the paper 1. It is enough. In addition, the pickup roller 30 has a shape consisting of a portion of a completely cylindrical shape in order to transfer the paper 1 to the image forming portion at regular intervals. Therefore, when the paper cassette 10 is mounted on the cassette mounting portion 20, a space corresponding to the radius of the pickup roller 30 exists between the paper presser plate 11 and the pickup roller 30 of the paper cassette. do.

The paper separation prevention member is installed at a position where the paper release preventing member is in contact with the paper pressing plate 11 of the paper feed cassette, above the paper feed cassette 10 in front of the pickup roller 30. At this time, it is preferable that the paper detachment preventing member is installed so that the tip thereof contacts the upper surface of the paper pressing plate 11 in the inclined state supported by the spring 15. Therefore, the length of the paper release preventing member is different depending on where the paper release preventing member is installed between the pickup roller 30 and the front end 12 of the paper feed cassette. In addition, the shape of the paper release preventing member can be made into any shape such as a rod shape as long as it can restrict the separation of the paper 1 subjected to upward force by the paper pressing plate 11. In addition, it is preferable that the material of the paper release preventing member uses an elastic body so as to absorb the elastic impact force of the paper pressing plate 11.

The paper release preventing member 50 of the embodiment shown in FIG. 3 is composed of a contact end 51 in contact with the paper on the paper pressing plate 11 and a spring 53 elastically supporting the contact end 51 downward. It is. The contact end 51 can be made into a shape having a smooth curved surface, but is preferably made of a freely rotating roller, that is, an idle roller.

Hereinafter, the operation of the paper feeder of the image forming apparatus according to the present invention having the above configuration will be described in more detail with reference to the accompanying drawings.

The user loads the paper 1 into the paper feed cassette 10. At this time, when the user presses the paper pressing plate 11 downward to facilitate the stacking of the paper 1, the latch 43 slides down on the inclined surface of the movable fixed end 42, so that the movable body 43 The latch 41 is caught by the fixed end 42 by moving laterally. When the latch 41 is caught by the fixed end 42, the paper pressing plate 11 is fixed to the bottom 13 of the paper feed cassette in a substantially parallel state as shown in FIG. Therefore, it is convenient for the user to put the paper in the paper feed cassette 10 and to insert the paper feed cassette 10 on which the paper 1 is loaded into the cassette mounting portion 20.

When the user inserts the paper cassette 10 loaded with the paper 1 into the cassette mounting portion 20, the lock moving body of the paper cassette 10 before the paper cassette 10 is completely mounted in the cassette mounting portion 20 ( 43 is pressed by the unlocking member provided on the side of the cassette mounting portion 20. When the unlocking member presses the upper end of the movable body 43, the spring 44 of the locking device is compressed and the clasp 41 is removed from the fixed end 42 of the movable body. When the clasp 41 comes out of the fixed end 42 of the movable body, the paper presser plate 11 springs upward by the spring 14 which elastically supports the paper presser plate 11.

Then, the idle roller 51 of the paper release prevention member 50 located above the paper pressure plate 11 and the paper 1 on the paper pressure plate 11 come into contact with each other, and the impact thereof is applied to the paper release prevention member 50. Will be absorbed by.

Therefore, the paper on the paper pressing plate is maintained as it is without being separated, so that the paper feed to the image forming unit by the feed roller is maintained smoothly.

As described above, according to the paper feeding device of the image forming apparatus according to the present invention, the paper cassette has a locking mechanism of the paper presser plate, which makes it convenient to load paper and to mount the paper cassette to the image forming machine. The phenomenon that the loaded paper is separated by the elastic return force of the paper pressing plate generated at the time of mounting is prevented by the paper release preventing member. Therefore, the paper is transported smoothly by the pickup roller.

The present invention is not limited to the above-described specific embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the invention as claimed in the claims. Such changes are intended to fall within the scope of the claims.

Claims (7)

A paper feed cassette provided with a paper pressing plate which elastically supports the loaded paper at an angle; A locking device installed at a bottom of the paper feed cassette and fixing the paper pressing plate to be located at the bottom; An unlocking member installed at one side of the cassette mounting unit in which the paper feeding cassette is mounted, and opening the locking device; And And a paper detachment preventing member installed on the ceiling of the cassette mounting unit to prevent the paper from being pulled upward by the paper presser that is elastically returned when the locking device is released by the unlocking member. A paper feeder of an image forming apparatus. According to claim 1, wherein the paper separation prevention member, And a resilient material capable of buffering the sheet pressing plate that is elastically returned. According to claim 1, wherein the paper separation prevention member, A contact end in contact with the paper on the paper pressing plate; And a spring for elastically supporting the contact end. The method of claim 3, wherein the contact end, A paper feeder of an image forming apparatus, characterized in that the roller rotates freely. According to claim 1, wherein the paper separation prevention member, The paper feeder of the image forming apparatus, characterized in that provided between the unlocking member and the tip of the paper feed cassette. The method of claim 1, wherein the locking device, A latch installed at a lower portion of the paper pressing plate; A moving body installed at a bottom of the paper feed cassette and having a fixed end to which the latch is caught; A spring for elastically supporting the movable body; When the paper pressing plate is pressed downward, the latch is caught by the fixed end, and the paper pressing plate is fixed to the bottom of the paper cassette, and when the moving body is pushed in the direction that the spring is contracted, the latch is pulled out of the fixed end and the paper pressing plate is pressed. The paper feeder of the image forming apparatus, characterized in that the inclined. The method of claim 6, wherein the unlocking member, The paper feeder of the image forming apparatus, characterized in that the projection is formed on one side of the cassette mounting portion, the upper end of the movable body of the locking device in a corresponding position.