JP2003104571A - Paper feed cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feed cassette for preventing paper jamming or overlapping feed due to excessive stacking. SOLUTION: When recording media 30, 32 are excessively stacked on a center plate 170, the preset number of recording media 30 are located at a regular position under a pawl 178. However, parts of the recording media, exceeding the preset number, are put on a protrusion and located higher than the protrusion. When the paper feed cassette in such a condition is mounted on a digital copying machine 50, the recording media 32 hit an upper wall 100b of an opening 100a. The paper feed cassette 150 cannot, therefore, be mounted on the digital copying machine 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed cassette on which recording media are loaded and which is detachably attached to an image forming apparatus such as a copying machine or a printer.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus for forming an image recorded on a document on a recording medium such as recording paper has been widely used. In general, a sheet feeding cassette for accommodating and accommodating a large number of recording media is detachably attached to the image forming apparatus.

When a user stacks recording media in a paper feed cassette, in order to regulate the number of stacked sheets to a predetermined number or less,
The maximum stacking position of recording media is illustrated in the paper feed cassette by a line or the like to instruct the user. However, since the user wants as little paper out of the paper feed cassette as possible, the line indicating the maximum stacking position is ignored, and a certain number of recording media are forcibly stacked (hereinafter referred to as "overloading"). There are things to do.

By the way, a paper feed roller (not shown) for feeding the recording media loaded in the paper feed cassette is set on the assumption that a predetermined number of recording media are loaded in the paper feed cassette. . Therefore, when the recording media are overloaded, the operation of the paper feed rollers and the like may be defective, and as a result, a paper jam (jam) or two or more recording media may be fed simultaneously. May occur.

[0005]

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a paper feed cassette that prevents jamming and double feeding due to overloading.

[0006]

A first paper feed cassette of the present invention for achieving the above object is a cassette tray in which a predetermined number of recording media are stacked in an image forming apparatus for forming an image on the recording media. And a regulation member that regulates the position of the recording medium loaded on the cassette holder, and (1) a recording medium loaded from the regulation member in a paper cassette that is detachably attached to the image forming apparatus. A claw for controlling the height of the recording medium loaded on the cassette pocket, and (2) a protrusion for mounting the recording medium that exceeds the regulation of the claw, extending in a direction toward It is a thing.

Here, the protrusion may (3) project upward from the upper surface of the claw.

A second paper feed cassette of the present invention for achieving the above object is a cassette tray in which a predetermined number of recording media are stacked in an image forming apparatus for forming an image on the recording media, and the cassette. In a paper feed cassette that is equipped with a restricting member that restricts the position of the recording medium loaded on the orchestra, and (4) one end of which is rotatably fixed to the restricting member. In addition, the other end is provided with a rotating member extending in the direction toward the loaded recording medium.

Here, the regulating member is (5) a trailing edge regulating plate for regulating the trailing edge position of the stacked recording media, or
It may be a side regulating plate that regulates the side edge position of the loaded recording medium, or a cassette pocket inner wall that regulates the rear edge or side edge of the loaded recording medium.

[0010]

DETAILED DESCRIPTION OF THE INVENTION [First Embodiment]

A first embodiment of the paper feed cassette of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a perspective view showing the external appearance of a digital copying machine to which a first embodiment of a paper feeding cassette of the present invention is detachably mounted. FIG. 2 is a perspective view showing a state where the paper feed cassette is pulled out from the digital copying machine of FIG. FIG. 3 is a schematic diagram showing the internal structure of the digital copying machine of FIG. FIG. 4 is a sectional view showing the paper feed cassette.

The copying machine 50 includes a first housing 60 in which a plurality of parts for reading an image recorded on a document are incorporated.
And a second housing 100 in which a plurality of parts for forming an image on a recording medium are incorporated. Second housing 100
Are arranged under the first housing 60, as shown in the figure. Therefore, the first housing 60 is mounted on the second housing 100. Further, the first housing 60 can be moved in the directions of arrows A and B along the upper surface of the second housing 100.

On the top surface of the copying machine 50, a rectangular parallelepiped original document pressure plate 62 which can be opened and closed is arranged. An optical housing 64, in which a known optical system (not shown) is incorporated, is arranged below the original pressure plate 62. Light source LED for optical system
(Not shown) and the like are provided. The upper surface (upper wall) of the optical housing 64 is a document table glass (not shown) on which a document is placed. The original pressure plate 62 and the optical housing 64 form a first housing 60.

An operation panel 102 for inputting the number of copies and the like is arranged on the front side of the second housing 100 with respect to the first housing 60. At the bottom of the second housing 100, a paper feed cassette 1 that stores a plurality of cut sheets
50 can be freely inserted into and removed from the second housing 100 (detachable)
It is installed. The right side wall of the second housing 100 is provided with a rectangular manual feed tray 106 capable of feeding a small-sized recording sheet such as a postcard. This bypass tray 106
Is rotated in the direction of arrow C (see FIG. 3) around the lower side portion 106a, and is opened to a position where a recording medium can be placed.

About half of the upper wall of the second casing 100 on the manual feed tray 106 side is a cartridge cover 132 that can be opened and closed. Process cartridge 1 described later
When attaching / detaching the cartridge 30 or performing jam processing, the first housing 60 is moved in the direction of arrow A to move the cartridge cover 1
Open 32.

A procedure for forming an image with the copying machine 50 will be described with reference to FIG.

When forming an image with the copying machine 50, the first housing 60 is placed at the image forming position (the position shown in FIG. 1). In order to form an image recorded on a document on a recording medium, the document pressure plate 62 is opened, and the document is placed on the upper surface of a document table glass (not shown) with the image side facing down.
This original is pressed and fixed by the original pressure plate 62. next,
By pressing an operation button or the like on the operation panel 102, the image recorded on the document is read by the optical system incorporated in the optical housing 64. The read image is converted into a digital signal, and this digital signal is used by the laser scanner 1
Sent to 10.

The signal transmitted to the laser scanner 110 is converted into laser light, and this laser light passes through the scanner mirror 110a and the folding mirror 110b which rotate at high speed, and the photosensitive drum 112 disposed in the process cartridge 130. Is irradiated. The photosensitive drum 112 is uniformly charged by the charger 111, and an electrostatic latent image is formed on the photosensitive drum 112 irradiated with the laser light.
This electrostatic latent image is developed with the developer supplied from the developing roller 114 to form a developed image.

On the other hand, a recording medium such as recording paper is fed from the paper feeding cassette 150 by the paper feeding roller 116 in the direction of arrow D (paper feeding direction), and is conveyed to the transfer device 122 by the conveying roller 118 and the registration roller 120. It In the transfer device 122, the photosensitive drum 1 is transferred onto the recording medium conveyed.
Twelve developed images are transferred. The recording medium on which the developed image is transferred is conveyed to the fixing device 126 by the conveying device 124. The fixing device 126 is provided with a fixing roller 126a and a pressure roller 126b.
The recording medium is conveyed while being sandwiched between a and 126b, and the developed image is fixed on the recording medium. The recording medium on which the developed image has been fixed in this manner is discharged by the paper discharge rollers 128 and stacked on the paper discharge tray 108.

The recording medium can be fed from the manual feed tray 106, and the procedure for forming an image on the recording medium fed from the manual feed tray 106 is the same as above. Further, the copying machine 50 also has a built-in electric component board 129 on which a power source for driving various components and electric components are mounted.

As described above, various parts and members are incorporated in the copying machine 50. Among these parts, the charger 111, the photosensitive drum 112, the developing roller 114, and the like are incorporated in the process cartridge 130.
As described above, the process cartridge 130 is detachably attached to the copying machine 50.

Referring to FIGS. 2 and 4, the paper feed cassette 150
Will be described.

The paper feed cassette 150 has a rectangular bottom wall 16
It has a cassette pocket 160 having an open upper surface and a rectangular middle plate 170. One side portion 172 of the middle plate 170 on the downstream side in the sheet feeding direction (direction of arrow D) extends in the orthogonal direction orthogonal to the sheet feeding direction.
It can move freely from and to the bottom wall 162 of zero. The above orthogonal direction is also the width direction of the recording medium stacked on the intermediate plate 170. Further, below the one side portion 172, this one side portion 172
A compression coil spring 152 for urging the upper part of the cassette pocket 160 away from the bottom wall 162 of the cassette pocket 160 is arranged.

On the other hand, the other side portion 174 of the middle plate 170 on the upstream side in the sheet feeding direction is attached near the bottom wall 162 so as to be freely rotatable within a predetermined angle range. When the one side portion 172 is lifted by the compression coil spring 152, the middle plate 170 moves from the other side portion 174 to the one side portion 1.
Incline upward toward 72.

A trailing end regulation for regulating the upstream end (rear end) of the recording medium 30 in the sheet feeding direction is provided upstream of the other side 174 of the middle plate 170 of the cassette player 160 in the sheet feeding direction (direction of arrow D). A plate 176 is arranged. A claw 178 extends from the upper end of the trailing edge regulation plate 176 in the direction toward the tip of the middle plate 170 (direction of arrow D). The claw 178 is formed on the middle plate 1
The height of the recording medium loaded on the 70 is regulated so that the middle plate 17
This is for allowing a predetermined number (for example, 250 or 500) of recording media to be stacked on 0. Also, nail 1
From the downstream side of the upper surface of 78 in the direction of arrow D, a protrusion 180
Is protruding upward.

Now, with reference to FIGS. 5 to 7, the manner in which the paper feed cassette 150 in which the recording medium is loaded on the intermediate plate 170 is mounted in the second housing 100 of the digital copying machine 50 will be described.

FIG. 5 is a partial cross-sectional view schematically showing a state in which an overloaded recording medium is placed on the protrusion. Figure 6
FIG. 6 is a schematic diagram showing how the paper feed cassette in the state shown in FIG. 5 is attached to the digital copying machine 50. FIG. 7 is a schematic diagram showing a state where the overloaded recording medium is bent. In these figures, the same components as those shown in FIG. 4 are designated by the same reference numerals.

When the recording mediums 30, 32 are overloaded on the intermediate plate 170, the predetermined number of recording mediums 30 are located at the regular position under the claw 178. However, the recording media 32 that exceed the predetermined number are placed on the protrusion 180 and are located at a position higher than the protrusion 180, as shown in FIG. By the way, the first housing 100 of the digital copying machine 50 is formed with an opening 100a for mounting the paper feed cassette 150. When attempting to mount the paper feed cassette 150 in the state shown in FIG. 5 in the digital copying machine 50, as shown in FIG.
The recording medium 32 strikes the upper wall 100b of a. Therefore, since the paper feeding cassette 150 cannot be mounted in the digital copying machine 50, paper jam and double feeding due to the number of recording media exceeding a predetermined number are prevented.

By the way, the recording mediums 30, 3 are formed on the intermediate plate 170.
When 2 is overloaded, the number of recording media 3 exceeds the predetermined number.
In some cases, the recording medium 32 may be curved because the end surface of the recording medium 32 abuts the side surface 180 a of the protrusion 180 as shown in FIG. Even in such a case, the paper feed cassette 150 can be replaced by the digital copying machine 50.
As shown in FIG. 7, the opening 10
The recording medium 32 strikes the upper wall 100b of 0a. Therefore, since the paper feeding cassette 150 cannot be mounted in the digital copying machine 50, paper jam and double feeding due to the number of recording media exceeding a predetermined number are prevented.

An example in which the notch 100c into which the protrusion 180 is inserted is formed in the upper wall 100b of the opening 100a will be described with reference to FIG.

FIG. 8 is a schematic diagram showing a state in which an overloaded sheet feeding cassette is about to be mounted in an opening having a notched upper wall.

When the paper feed cassette 150 loaded with a predetermined number of recording media 30 or less is mounted in the digital copying machine 50, the projection 180 of the paper feed cassette 150 is provided on the upper wall 10.
It is inserted in the notch 100c of 0b. On the other hand, when the overloaded paper feed cassette 150 is mounted on the digital copying machine 50, even if the number of recording media 32 that exceeds the predetermined number is small, the recording medium 32 surely hits the upper wall 100b. Therefore, even if the number of overloaded recording media is small, it is possible to more reliably prevent the paper feeding cassette 150 from being attached to the digital copying machine 50. As a result, paper jamming and double feeding due to the overloaded recording medium can be prevented more reliably. In this embodiment, the protrusion 180 is provided on the upper surface of the claw 178. However, the position of the protrusion is not limited to the upper surface of the claw as long as the recording medium can be placed beyond the claw 178. You may provide a protrusion directly in. [Second Embodiment]

A second embodiment of the paper feed cassette of the present invention will be described with reference to FIGS. 9 and 10.

FIG. 9 is an enlarged schematic view showing a part of the paper feed cassette of the second embodiment. FIG. 10 is a perspective view showing a rotating member of the paper feed cassette of the second embodiment.

At the end portion in the width direction (direction of arrow E) of the upper portion of the rear end regulating plate 252 of the sheet feeding cassette 250, the middle plate 170 is provided.
The MAX line indicating the maximum height of the recording medium loaded on the sheet is shown.

A plate-shaped rotating member 256 is rotatably fixed to the central portion in the width direction of the upper portion of the trailing edge regulating plate 252. One end portion 256 a of the rotating member 256 has the rear end regulating plate 2
It is rotatably attached to 52. Rotating member 256
Extends in a direction toward the front end of the intermediate plate 170, and the front end 256b is inclined slightly upward.

When the number of recording media stacked on the intermediate plate 170 exceeds the predetermined number, the recording media of the number exceeding the predetermined number push up the rotating member 256 to rotate in the arrow F direction. In this case, the rotated rotary member 256 is located at a position higher than the position of the rotary member 256 (the normal position shown by the solid line in FIG. 9) when a predetermined number of recording media or less are stacked on the intermediate plate 170. It will be located at the position indicated by the dotted line). Therefore, when the recording medium is overloaded in the paper feed cassette 250, the paper feed cassette 2 is loaded in the digital copying machine 50.
Since the rotating member 256 abuts on the upper wall 100b of the opening 100a for mounting the sheet 50, the sheet feeding cassette 250 cannot be mounted on the digital copying machine 50. As a result, it is possible to prevent paper jams and double feeding due to recording media exceeding the predetermined number.

In the first and second embodiments, the claw 178, the protrusion 180, and the rotating member 256 are provided on the rear end regulating plates 176 and 252 arranged on the cassette pocket 160, but their positions are rear. It is not limited to the edge regulation plate. The claws, protrusions, and rotating members are side regulation plates that are fixed to the cassette pocket to regulate the trailing edge position of the loaded recording medium, or cassette pockets that regulate the trailing edge or side edge of the loaded recording medium. It may be provided on the inner wall. Obviously, when these are provided, the same effects as when they are provided on the trailing edge regulating plate are obtained.

Here, the direction in which the paper feed cassette is attached to and detached from the main body of the image forming apparatus differs depending on the model. For this reason, the direction in which the user stacks the recording media also differs. The protrusions and the like in the present invention may be an obstacle during loading depending on the position. Therefore, the fact that the fixing position of the protrusion or the like may be the regulation plate or the cassette is advantageous when considering the usability.

[0041]

As described above, in the first paper feed cassette of the present invention, when the number of recording media loaded on the middle plate exceeds the predetermined number, the recording medium after the number of the recording media exceeding the predetermined number is printed. The end portion is placed on the upper end of the protrusion, or the rear end portion of the recording medium hits the side surface of the protrusion and the recording medium bends (curves) upward. In any case, the upper portion of the recording medium loaded on the intermediate plate is located at a position higher than the upper ends of the protrusions. Therefore, by setting the size of the opening for loading the paper feed cassette in the image forming apparatus so that the one located at a position higher than the upper end of the protrusion cannot be inserted, the recording medium exceeding the predetermined number is stacked on the intermediate plate. The supplied paper cassette cannot be installed in the image forming device. As a result, it is possible to prevent paper jams and double feeding due to recording media exceeding the predetermined number.

Here, when the projection is projected upward from the upper surface of the claw, the projection is provided on the claw, so that the recording medium can be reliably placed.

In the second paper feed cassette of the present invention,
If the number of recording media loaded on the middle plate exceeds the specified number,
The recording medium exceeding the predetermined number pushes the rotating member to rotate. In this case, the rotated rotating member is located at a position higher than the position (regular position) of the rotating member when a predetermined number of recording media or less are stacked on the intermediate plate. Therefore, by setting the size of the opening for mounting the paper feed cassette in the image forming apparatus so that the one located at a position higher than the rotating member at the regular position cannot be inserted, the recording medium having a predetermined number of sheets or more may not be inserted. The paper cassette loaded on the printer cannot be installed in the image forming device. As a result, it is possible to prevent paper jams and double feeding due to recording media exceeding the predetermined number.

Here, the regulating member is a trailing edge regulating plate that regulates the trailing edge position of the loaded recording medium, a side regulating plate that regulates the side edge position of the loaded recording medium, or is loaded. In the case of the inner wall of the cassette pocket that regulates the rear end or the side end of the recording medium, a claw or the like can be provided at a position or member that does not interfere when the user stacks the recording medium in the paper feeding cassette.

[Brief description of drawings]

FIG. 1 is a perspective view showing an external appearance of a digital copying machine to which a first exemplary embodiment of a paper feeding cassette of the present invention is detachably mounted.

FIG. 2 is a perspective view showing a state in which a paper feed cassette is pulled out from the digital copying machine of FIG.

FIG. 3 is a schematic diagram showing an internal structure of the digital copying machine of FIG.

FIG. 4 is a sectional view showing a paper feed cassette.

FIG. 5 is a partial cross-sectional view schematically showing a state in which an overloaded recording medium is placed on a protrusion.

FIG. 6 is a diagram illustrating the paper feeding cassette in the state shown in FIG.
It is a schematic diagram which shows a mode that it is attached to 0.

FIG. 7 is a schematic diagram showing a state in which an overloaded recording medium is bent.

FIG. 8 is a schematic view showing a state in which an overloaded sheet feeding cassette is about to be attached to an opening having an upper wall in which a notch is formed.

FIG. 9 is a schematic view showing an enlarged part of the paper feed cassette of the second embodiment.

FIG. 10 is a perspective view showing a rotating member of the paper feeding cassette of the second embodiment.

[Explanation of symbols]

50 digital copier 150,250 paper feed cassette 176,252 Rear end regulating plate 178 claws 180 protrusion 256 rotating member

Claims (4)

[Claims] 1. An image forming apparatus for forming an image on a recording medium, comprising: a cassette pocket on which a predetermined number of recording media are stacked; and a regulating member for regulating a stacking position of the recording medium stacked on the cassette pocket. A paper feed cassette detachably attached to the image forming apparatus, the pawl extending in a direction from the regulating member toward the loaded recording medium and regulating the height of the recording medium loaded on the cassette pocket, A paper feed cassette, comprising: a protrusion for placing a recording medium that exceeds the regulation of the claw. 2. The paper feed cassette according to claim 1, wherein the projection is projected upward from an upper surface of the claw. 3. An image forming apparatus for forming an image on a recording medium, comprising: a cassette holder on which a predetermined number of recording media are stacked; and a regulating member for regulating a stacking position of the recording medium stacked on the cassette holder. In a paper feed cassette detachably attached to the image forming apparatus, one end of the paper feed cassette is rotatably fixed to the regulating member, and the other end thereof extends in a direction toward a loaded recording medium. A paper feed cassette characterized by having. 4. The regulating member is a trailing edge regulating plate for regulating the trailing edge position of the loaded recording media,
3. A side regulating plate for regulating a side end position of a loaded recording medium, or a cassette pocket inner side wall for regulating a rear end or a side end of the loaded recording medium. , Or 3, the paper feed cassette.