JPS6236937B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a paper feeding device that loads paper cut into a predetermined size on a paper feeding tray and feeds the paper one by one using a bottom feed method. In particular, the present invention relates to a paper feeding device characterized in that a pressing mechanism provided in a paper feeding tray for pressing the paper against a feed roller has been improved.

[Conventional technology]

In a recording device such as a printer or a copying machine that uses paper arranged in a fixed size, the paper feeding device is usually constructed using a cassette type paper feeding tray for ease of paper replacement.
Paper feeding methods of such paper feeding devices include an up-purfeed method in which the sheets stacked in the paper feed tray are fed sequentially from the top layer of paper, and a top feed method in which the sheets are fed from the bottom layer first. There is a bottom feed method. In a bottom-feed paper feeding device, it is easy to replenish the paper feed tray with paper, and since the paper that has been set first is fed first, old paper does not remain in the paper feed tray. This has the advantage of eliminating the trouble caused by

FIG. 1 shows an example of a conventional bottom feed type paper feeding device. A plurality of sheets of paper 2 are stacked in a paper feed tray generally designated by reference numeral 1, and a portion of the circumferential surface of a feed roller 3 rotatably mounted on the main body of the apparatus is perforated in the main body 4 of the tray. It passes through the hole 4A and comes into pressure contact with the lowest paper 2A. A fixed cover 5 that covers the leading edge of the paper 2 is fixed to the tray body 4, and a paper feed port 6 is formed by the lower edge of the fixed cover 5 and the tray body 4, and a movable cover that covers most of the paper 2 The base of 7 is attached by a hinge 8 so as to be openable and closable. A latch mechanism 9 is provided on the free end side of the movable cover 7. The latch mechanism 9 includes a locking member 12 that locks a pin 11 fixed to the free end of the movable cover 7.
The movable cover 7 is latched or released by rotating the locking member 12 about a shaft 15.

A pressing mechanism 17 is disposed on the back side of the movable cover 7, and the base of a pressing member 18 included in this mechanism is pivotally attached to a shaft 19, and each end of this shaft 19 is fixed to the movable cover 7. A pair of brackets 2
It is installed on 1. The pressing member 18 is moved in the direction indicated by the arrow 2 by the elasticity of a torsion spring 22 attached to the shaft 19.
It is provided with a rotational behavior in three directions, and its free end 18A is pressed against the uppermost sheet 2B. The free end 18A of the pressing member 18 is located above the feed roller 3 when the paper feed tray 1 is viewed from the side, and presses the paper 2 against the feed roller 3.

[Problem that the invention seeks to solve]

In the paper feeding device configured in this way,
By intermittently rotating the feed roller 3 in the direction of arrow 25, the lowest sheets 2A are sequentially fed from the paper feed port 6 in the direction of arrow 26. However, in this device, when an attempt is made to release the latch mechanism 9 and rotate the movable cover 7 in the direction of the arrow 27 in order to replenish the paper 2 to the paper feed tray 1, the pressing member 18 is torsioned by the spring. Due to the elasticity of 22, it rotates in the direction of arrow 23. The top sheet 2 is therefore pressed against its free end 18A.
B was moved in the direction of arrow 28 (the direction opposite to the feeding direction 26 of paper 2), and the stacked paper 2
The problem was that it disturbed the arrangement of the objects. Conversely, when closing the movable cover 7, the pressing member 18 is in a position rotated in the direction in which the torsion spring 22 is relaxed, so its free end 18A hits the paper 2 and the movable cover 7 cannot be closed. There were also drawbacks. In such a state, the pressing member 18 had to be previously rotated back in the direction opposite to the arrow 23 by an external manual operation and the movable cover 7 had to be closed, which was extremely troublesome.

[Purpose of the invention]

The purpose of the present invention is to: When opening and closing a movable cover,
It is an object of the present invention to provide a paper feeding device that allows a pressing member to press and separate the paper smoothly.

[Means for solving problems]

In the paper feeding device of the present invention, a relatively weak return spring is disposed between the pressing member and the movable cover, and the pressing member is kept close to the back side of the movable cover when the movable cover is opened. In addition, for the tray body, a pressure spring with a strong elasticity capable of resisting the above-mentioned return spring is applied to an operating pin, and by rotating a pressing member with this operating pin, a required pressure is applied to the paper. The above-mentioned purpose has been achieved.

〔Example〕

The present invention will be explained in detail below with reference to an embodiment shown in the drawings.

In FIGS. 2 and 3, parts having the same functions as those shown in FIG. 1 are given the same reference numerals. In FIGS. The boss portion 41B is fitted onto the shaft 19 to be rotatably supported. The pressing member 41 is moved by the arrow 23 due to the elasticity of a return spring 42 which has a relatively weak elasticity and whose ends are respectively locked between the movable cover 7 and the movable cover 7.
The rotational behavior is given in the opposite direction, that is, in the direction approaching the back side of the movable cover 7.

On the left and right sides of the upper surface of the tray body 4, there are a pair of side plates 43, 44 that adjust the width of the paper 2, as shown in FIG.
are fixedly installed in parallel, and furthermore, a pair of pin housings 45 and 46 are respectively fixedly installed on the outside thereof. In FIG. 2, the pin housing 45
and a guide hole 4 drilled in the frame body 4
7 and 48, an operating pin 49 having a flange 49A is mounted so as to be vertically movable. Actuation pin 4
9 is given the habit of rising by the elasticity of an extensible pressing spring 51 whose ends are pressed against the flange 49A and the frame body 4, and the actuating pin 52 in the other pin housing 46 is also actuated. pin 49
It is configured in the same way.

When the movable cover 7 is closed as shown in FIG.
It is in pressure contact with the back surface of the short arm 41C of No. 1, giving the pressing member 41 the ability to rotate in the direction of arrow 23. The elasticity of the pressing spring 51 is set to be relatively larger than that of the return spring 42, and acts on the pressing member 41 with a force sufficient to resist the return spring 42. Due to the rotational force applied to the pressing member 41, its free end 41B presses the uppermost sheet 2B and presses the lowermost sheet 2A against the peripheral surface of the feed roller 3. While this press-contact action is being performed, an appropriate gap is always formed between the flange 49A of the operating pin 49 and the upper rear surface of the pin housing 45.

When the number of sheets of paper 2 in the paper feed tray 1 decreases and it is to be replenished, the latch mechanism 9 is released and the movable cover 7 is rotated in the direction of arrow 27 to be opened.
When the movable cover 7 is opened, the short arm 41C of the pressing member 41 immediately separates from the operating pins 49, 52. Therefore, the pressing spring 51 against the pressing member 41
The rotational action of is eliminated, and the pressing member 41 can be retracted toward the movable cover 7 by the elasticity of the return spring 42. This eliminates the inconvenience of the uppermost sheet 2B being moved by the free end 41A of the pressing member 41 in the direction opposite to the sheet feeding direction (in the direction of arrow 28). Furthermore, when the movable cover 7 is closed, the free end 41A of the pressing member 41 is retracted to the movable cover 7 side, so the phenomenon of the free end 41A hitting the paper 2 is eliminated, and the movable cover 7 can be smoothly closed. can.

〔Effect of the invention〕

As described above, according to the present invention, a return spring is disposed between the pressing member and the movable cover, and an operating pin is provided in the frame body to rotate the pressing member with a force capable of resisting the spring. Therefore, when opening and closing the movable cover, problems such as the dislocation of the uppermost sheet of paper caused by the pressing member and the inability to close the movable cover due to collision between the pressing member and the paper, which occurred in conventional devices, are eliminated. The movable cover can be opened and closed normally without any manual operation, and the paper feed tray can be easily replenished with paper.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an example of a conventional paper feeding device, FIG. 2 is a side view of a paper feeding device showing an embodiment of the present invention, and FIG. 3 is a perspective view showing essential parts of the same device. It is. 1... Paper feed tray, 2... Paper, 3... Feed roller, 4... Tray body, 5... Fixed cover, 7... Movable cover, 18, 41... Pressing member, 45, 46... Pin housing ,49,52
... Operating pin, 42 ... Return spring, 51 ... Pressing spring.

Claims (1)

[Claims] 1. A plurality of sheets 2 of a certain size are placed in a paper feed tray 1.
In a bottom feed type paper feeding device that feeds paper by intermittent rotation of a feed roller 3 which is loaded on a tray and whose peripheral surface partially penetrates the tray body 4 and is in pressure contact with the lowest paper 2A, A movable cover 7 that can be opened and closed freely covers most of the paper 2, and a movable cover 7 that is movably disposed on the back side of the movable cover 7. Paper 2B with the pressing part at the end 41A at the top
a pressing member 41 that presses the paper 2 against the feed roller 3 by contact with the feed roller 3; and a rotational behavior that allows the pressing member 41 to move closer to the movable cover 7 and away from the paper 2 when the movable cover 7 is opened. Return spring 4
2 and a pin housing 4 fixed to the tray body 4
When the movable cover 7 is closed, the pressing member 41 is rotated by the strong elasticity of the pressing spring 51 that can resist the return spring 42, and the sheet 2 is A paper feeding device characterized in that a paper feeding tray 1 is constituted by actuating pins 49 and 52 for pressing the paper.