JPS6234660B2 - - Google Patents

Description

Detailed Description of the Invention <Technical Field> The present invention relates to a paper feeding cassette for automatic paper feeding in a copying machine or the like.

<Prior art> Generally, in a copying type electrophotographic copying machine, a toner image is formed on a photoreceptor through charging, exposure, and development steps, and this toner image is transferred onto a transfer paper by a corona discharge means or the like. . Thereafter, the toner image is semi-permanently fixed onto the transfer paper by a fixing device. Normally, paper having a weight of about 50 to 250 (g/m ² ) is practically used as the transfer paper. Among these, approximately 60 to 90 (g/m ² ) paper is stored in a paper feed cassette etc. because it is used frequently and is easy to feed automatically, and is fed reliably by the automatic paper feed mechanism. Ru.

Figure 1 is a sectional view showing the state in which the cassette of a normal cassette type automatic paper feed mechanism is installed in the main body of the copying machine.
FIG. 2 is a top view showing the cassette viewed from above. The cassette 11 stores a normal transfer paper 16 on a transfer paper mounting table 12 rotatably supported on a side wall of the cassette 11. One end of the push-up member 14 is rotatably supported by the main body 17, and the other free end is arranged so as to come into contact with the lower surface of the transfer paper mounting table 12. The elastic member 15 has one end attached to the main body 17 and the other end to the push-up member 14, and applies a force to push up the transfer paper mounting table 12 through the push-up member 14. One end of the transfer paper presser 13 is rotatably supported by the side wall of the cassette 11, and the other end is shaped to restrict the tip and top surface of the transfer paper 16. Further, a protrusion 13a is provided at a portion facing the side wall of the cassette 11, and this protrusion 13a is fitted into an elongated hole 11a provided in the side wall of the cassette. And this long hole 11
The protrusion 13a is movable by the length of the long axis a, and this becomes the movement width of the transfer paper presser 13.

As a result, the uppermost position of the pushed-up transfer paper 16 is at a constant height _h1 from the bottom of the cassette.
Also, a paper feed roller 19 rotatably shafted on the main body.
The height of is also kept constant at _h2 . This is to stabilize the paper feeding force by always keeping the distance between the paper feed roller 19 and the transfer paper 16 constant, and to make the position of the fed transfer paper 16 into the main body 17 constant.

With the paper feed cassette 11 having the above-described structure, there were cases in which the push-up member 14 interfered with the operation of attaching and detaching the cassette, making it impossible to attach and detach the cassette as desired. Therefore,
The mechanism of the push-up member 14 itself is assembled into a cassette 11.
There is one that is arranged in the main body of the device and is configured to push the mounting table 12 upward. This certainly makes it easier to attach and detach. However, conventionally, a coil spring or the like is provided from the lower part of the loading table 12 facing the paper feed roller 19 to push up the loading table 12, so that the paper storage capacity is reduced by the thickness of the spring.

<Object of the Invention> The present invention provides a paper feeding cassette that simplifies the operation of attaching and removing the automatic paper feeding cassette to a copying machine and does not reduce the paper storage capacity in the cassette. .

<Example> The present invention will be described in detail using a paper feed cassette for thick paper as an example.

3 is a perspective view showing one embodiment of the paper feeding cassette of the present invention, FIG. 4 is an enlarged view of the main part of FIG. 3, and FIG. 5 is a sectional view taken along the line A-A in FIG. 4. .
In the figure, reference numeral 21 denotes a cassette main body that is detachably installed in the paper feed section of the main body of the copying machine. This cassette 21 has a paper guide 22 on the bottom that regulates and guides both sides of thick letters such as postcards, and a regulating piece 23 that places the thick letters on the top and regulates the rear end of the thick letters.
A cradle 23 having A ₁ , a regulating claw 24 that regulates the tip of the thick letter and feeds it one sheet at a time, a paper position regulating member 25 that regulates the top position of the thick letter placed on the cradle 23, It has a spring 26 that always pushes up the pedestal 3, a spring holding member 27 that holds the spring 26, and a stopper 28 that restricts the movement range of the paper position regulating member 25.

The pedestal 23 is used to control the rear end of the thick letter.
Both side edges are bent approximately 90 degrees to form a regulating piece 23 _-1 , and an extension part 23 _-2 is formed by extending the central part of the regulating piece 23 -1.
has been established. As shown in the figure, the extension portion _23-2 is bent upward relative to the pedestal 23, and the regulating piece _23-1 is similarly provided at this bent portion. One end of a spring 26 is fixed to the upper part of this extension 23 _-2 . The other end of the spring 26 is connected to the spring holding member 2.
7, the above extension part 23
_-2 in the direction of pushing down, and as a result pushes up the pedestal 23 on which the paper is placed about the rotating shaft 29, which will be described later.

In addition, the pedestal 23 has a rotating shaft 2 at the regulating piece 23 _-1 .
9 is attached, and since this rotating shaft 29 is pivotally supported in a long hole 22 _-1 bored in the paper guide 22, it is rotated around this rotating shaft 29. The other end of the spring 26 is fixed to a spring holding member 27 fixed to the bottom of the cassette, and pushing down the extension _23-2 pushes the pedestal 23 upward. Paper position regulating material 25
has claw portions 25 _-1 facing the corner portions of both ends of the thick letter and provided to regulate the position of the paper,
It is rotatably supported by the paper guide 22, and is provided with a hole _25-2 for regulating the rotation range. A stopper 28, which is formed by appropriately cutting and bending the paper guide 22, is inserted into the hole _25-2 . In other words, the edge of the hole _25-2 is engaged with the stopper 28, so that the rotation range of the paper position regulating member 25 is regulated. A regulating claw 24 is fixed to the frontmost bent portion 25 _-3 of this sheet position regulating member 25.
_-1 and the tip of the regulating claw 24, a gap d is formed as shown in FIG. 4 through which a sheet of thick paper can pass.

In the configuration as described above, the cassette 21
If it does not accommodate thick letters, as shown in Figure 5,
The pedestal 23 is pushed upward by the spring 26, and the leading edge of the pedestal 23 is engaged with the claw portion _25-1 and pushed up. Therefore, the paper position regulating member 25 is also pushed up at the same time, but its movement is caused by the stopper 2.
8 and hole _25-2 , and each mechanism is stopped in the state shown in the figure.

Therefore, the pedestal 23 can be pushed down to the bottom of the cassette 21, and a large number of thick letters 30 can be accommodated within that range. In other words, the pedestal 23 can be pushed down regardless of the thickness of the spring 26, and the paper storage capacity is not reduced at all due to the thickness of the spring 26. If you store the paper like this, the 6th
As shown in the figure, the top of the thick letter 30 is always positioned at the same height regardless of the number of sheets, and the pedestal 23 is lowered by the thickness of the thick letter 30.

FIG. 6 shows the state in which the cassette 21 is mounted on the copy paper main body, and the paper feed roller 31 is shown opposite to this mounting portion. The paper feed roller 31 has a notch facing the thick letter 30 when not in operation, and rotates when in operation so that its circumferential surface comes into contact with the thick letter 30 and feeds the paper.

When the paper feeding roller 31 rotates, the uppermost thick letter 30 _-1 is fed through the distance d between the claw portion 25 _-1 of the paper position regulating member 25 and the tip of the regulating claw 24. At this time, the next thick letter 30 _-2 is the regulation claw 24.
Paper feeding is regulated at , and only the uppermost thick letter 30 _-1 is fed as shown in FIG. The distance d between the claw portion 25 _-1 and the tip of the regulating claw 24 is such a gap that two or more thick letters 30 cannot pass through.

As an example, when d was set to 0.355 mm for a thick letter 30, such as a postcard, which had a thickness of about 0.25 mm, no double sheet feeding occurred at all.

Here, in FIG. 6, the biasing force of the spring 26 is applied to the thick paper 30 _-1 on the claw portion 25 _-1 of the paper feed claw 25.
Acts to press against. In this state, it is difficult to feed the thick letter 30 _-1 at the top. However, when feeding paper, the paper feed roller 31 pushes down the entire thick paper 30 as shown in FIG.
The force exerted by the spring 26 between the claw portion 25 _-1 and the thick letter 30 _-1 is eliminated. This does not affect paper feeding in any way.

In FIG. 8, a resin sheet material 32 having a low coefficient of friction, for example, a polymer, is fixed to the surface of the claw portion 25 _-1 of the paper position regulating member 25 facing the thick letter 30, and the uppermost thick letter 30 _-1 and the claw portion 25 _-1 to further reduce problems during paper feeding due to pressure contact force. In other words, when feeding paper, the uppermost thick letter 30 _-1 can be made to slide more smoothly, and the paper can be fed more smoothly. It is appropriate to attach the resin sheet material 32 using an adhesive.

As mentioned above, when feeding paper, the spring 2
A biasing force of 6 acts between the paper feed roller 31 and the thick paper 30 _-1 during paper feeding, and the thick paper 30 _-1 is fed with a stronger conveyance force.

Although the present invention has been described using thick letters as an example, the present invention is not limited to thick letters, and can of course be applied to light, stiff, and thin paper that has been commonly used in the past.

As explained above, according to the paper feed cassette of the present invention, there is no need to push up the pedestal on which the paper is placed from below, and even if the fulcrum shaft for rotating the pedestal is located at the bottom of the cassette, the pedestal does not need to be pushed up from the bottom. Since the cassette can be rotated and the paper accommodating capacity can be secured at the full height of the cassette, even a cassette with a small height can accommodate the required amount of paper. This is an effect that can only be achieved by bending the pedestal and providing a fulcrum shaft at this bent part.Also, even if a biasing means for pushing up the pedestal is provided in the cassette, this biasing means will not be able to accommodate the paper. There is no reduction in capacity, and the effect of simplifying the operation of attaching and detaching the cassette by providing the biasing means within the cassette is not impaired.

[Brief explanation of the drawing]

1 and 2 are a sectional view and a top view showing an example of a conventional automatic paper feeding cassette, FIG. 3 is a perspective view showing an embodiment of the automatic paper feeding cassette according to the present invention, and FIG. is an enlarged view of the main part of Figure 3, and Figure 5
The figure is a cross-sectional view of the A-A class in Figure 3, Figures 6 and 7.
The figure is a cross-sectional view of a cassette for explaining the operation of the present invention, and FIG. 8 is a partial cross-sectional view showing another embodiment of the present invention. 21: Cassette, 22: Paper guide, 23: Rest, 23 _-2 : Extension part, 24: Regulating pawl, 25: Paper position regulating material, 25 _-1 : Claw part, 26: Spring,
27: Spring holding material, 31: Paper feed roller.

Claims (1)

[Claims] 1. Detachably installed in the paper feed section of the main body of the copying machine,
The paper feed cassette 21 that accommodates a large number of sheets includes a pedestal 23 for placing the sheets stored in the paper cassette main body, and a pedestal 23 extending from the pedestal and bent upward. An extended portion 23 _-2 provided, a regulating plate 23 -1 formed at the bent portion of the extended portion to regulate the rear end of the paper to be accommodated, and a regulating plate 23 _-1 provided near the bent portion to rotatably support the pedestal. a fulcrum shaft 29, and a biasing means 26 provided corresponding to the extension for applying a downward force from the upper part of the extension to push the pedestal upward about the fulcrum shaft;
A paper feeding cassette characterized by comprising: