JPH07149447A - Paper feeding device - Google Patents

Abstract

PURPOSE:To perform smooth delivery of recording papers without needing high manufacturing precision and assembly precision for a hopper plate and a separation claw, realize reduction of a cost, and to facilitate setting of the recording paper. CONSTITUTION:A hot plate 3 is arranged in a case 1 in a state that it is energized upward through the force of a spring and a recording paper is placed thereon. A paper feeding device is provided at the front plate side of the case 1 with a vertically movable separation claw 8 brought into contact with the front end corner part of the recording paper and separate a topmost recording paper; an operation lever 10 by which a hopper plate 3 is pressed down against the energizing force of the spring; and a separation claw holding mechanism to exert a push up force on the separation claw 8 in interlock with displacement of the operation lever 10. The separation claw holding mechanism comprises a rod-form spring 11; and a lower spring support 1b. The spring 11 is engaged with two end parts, an intermediate part therebetween is pressed down by the operation lever 10, and when the intermediate part is pressed down, it is forced into contact with the lower spring support 1b and two end parts are caused to leap up. When the operation lever 10 is released, the separation claw 8 is independently operated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device.

[0002]

2. Description of the Related Art As is well known, a sheet feeding device such as a printer or a copying machine is provided with a hopper plate on which a recording sheet is placed by being biased upward by a biasing means.
Separation claws are provided that come into contact with the front end corners of the recording paper, and the recording papers are curled by the separation claws when the recording papers are fed so that they can be separated one by one.

By the way, conventionally, as a supporting member for the separating claw,
An ear portion that can be engaged with the middle plate (hopper plate) is provided, and when the middle plate is pushed down via a cam when setting the recording paper, a pushing force is applied to the ear portion and the support member swings, In some swinging operations, the separating claw is pushed up (Japanese Patent Laid-Open No. 61-101330). After the recording paper is set, the separating claw is in contact with the surface of the recording paper by its own weight. The separation claw can move freely in the upward direction, and when the recording paper is sent out, it moves upward against the dead weight to pass the recording paper.

[0004]

However, according to this conventional example, the separating claw is in contact with the recording paper by its own weight and is always interlocked with the displacement of the intermediate plate. When the rises, the separation claws descend in conjunction with this. Since the joining force of the separating claw to the recording paper is due to its own weight, it is difficult to set the moment, and if the manufacturing accuracy and assembly accuracy of the intermediate plate, support member, and separating claw vary, the separation of the intermediate plate due to displacement The amount of displacement of the claws may vary, the joining state with the recording paper may vary, and a gap may be formed between the upper surface of the recording paper and the separation claw. Therefore, the separation claw may not be able to separate the recording sheets one by one. Therefore, high manufacturing accuracy and assembly accuracy are required for the intermediate plate, the supporting member, and the separating claws, which causes a high cost. Further, if the manufacturing accuracy and the assembly accuracy of the separation claws are left and right, the displacement amounts of the left and right separation claws at the time of setting the recording paper are different, and it is difficult to set the recording paper. Therefore, the separation claws are required to have high manufacturing accuracy and assembling accuracy on the left and right sides, resulting in high cost.

Therefore, an object of the present invention is that the hopper plate and the separating claw need not have high manufacturing precision and assembly precision, the recording paper can be smoothly fed out, the cost can be reduced, and the recording paper can be easily set. It is to provide a sheet feeding device having a simple structure.

[0006]

The features of the sheet feeding device of the present invention are that a hopper plate on which a recording sheet is placed, an urging means for urging the hopper plate upward, and recording when the recording sheet is sent out. A vertically movable separation claw that abuts the front edge of the paper to separate the uppermost recording paper, and an operation lever that is displaceably supported and that can push down the hopper plate against the urging force of the urging means. And a separation claw holding mechanism that applies a lifting force to the separation claw in conjunction with the displacement of the operation lever,
The separation claw holding mechanism has rod-shaped springs with which the separation claws are engaged at both ends and the middle part is pushed down when the operation lever is displaced, and springs provided on both sides of the operation lever from the upper side when the operation lever is displaced. And a lower spring bearing against which it abuts.

Another feature resides in that both sides of the operating lever are provided with upper spring bearings against which the spring is abutted from the lower side when the operating lever is released.

[0008]

When the operating lever is operated to push down the hopper plate, the separating claw holding mechanism applies a pushing force to the separating claw in conjunction with this, and the space between the hopper plate and the separating claw is opened. When the operating lever is released, the hopper plate and the separating claw operate independently of each other, and the separating claw makes elastic contact with the recording paper by the spring force stored in the spring and is lifted by the curl of the recording paper. Smoothly feed the recording paper one by one.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, the paper feed cassette 100 is attached to a printer (not shown) and used for automatic paper feed. As shown in FIGS. 1, 3 and 4,
A hopper plate 3 biased upward by a torsion spring 2 having a bent wire shape is mounted in the case 1 of the paper feeding cassette 100, and the recording paper 9 is placed on the hopper plate. It is like this.
At the center of the front end of the hopper plate 3, there is provided a pressing portion 3a against which an operation lever 10 described later comes into contact and is pressed. A pair of cork thin plates 4 for preventing the recording paper 9 from slipping are attached to the front part of the hopper plate 3, and a pair of picking rollers 12 (see FIGS. (Shown in FIG. 3) are arranged to face each other. The upper part of case 1 is
As shown in FIG. 1, a case lid 5 is attached, and the case lid 5 is rotatable around a rear end portion thereof.
It is possible to remove it.

As shown in FIGS. 1 and 2, a side plate 7 for restricting the movement of the recording paper 9 in the width direction is provided upright in the case 1, and a front portion of the side plate 7 is separated from the side plate as described later. In order to support the claw 8, a part thereof extends outward in the width direction of the recording paper and extends upright 7a.
And a hole 7b is provided behind the standing portion.

The separating claw 8 is supported so as to be displaceable in the vertical direction by rotatably fitting the pin portion 8a thereof into the hole 7b of the side plate 7, and the outer surface of the side plate 7 and the above-mentioned standing portion. The movement of the recording paper 9 in the width direction is regulated by being sandwiched between the recording paper 9 and 7a. When the lifting force acts on the separation claw 8, the separation claw 8
Rotates about the pin portion 8a and is pushed upward. The separation claw 8 has a hook-shaped portion 8b that is bent inward at the front portion, and the rear side surface 8c of the hook-shaped portion 8b is a tapered surface that extends obliquely forward toward the inside. A substantially triangular roof 8d is provided on the upper side of the front part of the separation claw 8, and the roof 8d abuts on the front end corner surface of the recording paper 9. Further, as shown in FIGS. 2 and 4, on the front surface of the separation claw 8, a recess 8e that engages with an end of a spring 11 described later is formed.
A spring engaging portion 8f having a
The lower part of the is a protruding portion 8g to the front. The protruding portion 8g comes into contact with a stopper 1a provided on the front surface of the case 1 to regulate the upper limit of the separation claw 8.

As shown in FIGS. 8 to 10, at the center of the front end portion of the case 1, an operating lever 10 is rotatably mounted around the front end portion 10a. Operating lever 10
When is pressed, the operation lever 10 rotates about the front end portion 10a, and the rear end portion 10b of the operation lever 10 presses the pressing portion 3a of the hopper plate 3.
On the lower surface of the operating lever 10, there is provided a contact piece 10c capable of contacting an intermediate portion of a spring 11 described later and pushing down the spring.

1 and 8 are provided on the rear surface of the front plate of the case 1.
As shown in FIG. 10, a pair of lower spring bearings 1b are provided on both sides of the operating lever 10 against which a spring 11, which will be described later, abuts when the operating lever 10 is pressed. Also,
Between the pair of lower spring bearings 1b, there is a pair of upper spring bearings 1c which are close to the lower spring bearings 1b, and in which the operation lever 10 is in a released state, to which a spring 11 described later abuts from below. It is provided. It should be noted that the upper spring bearing 1c is projected rearward longer than the lower spring bearing 1b, and the end of the straight portion 1 extends downward.
It is d.

A rod-shaped spring 11 formed of a piano wire is sandwiched between the lower spring receiver 1b and the upper spring receiver 1c. The straight portion 1d prevents the spring 11 from coming off between the spring receivers 1b and 1c.
Both ends of the spring 11 are engaged with the recesses 8e of the separation claw 8, and when the separation claw 8 is pushed up by the recording paper 9 or the hopper plate 3 and comes into contact with the stopper 1a, the spring 11 is released.
Is in contact with the upper spring receiver 1c and both ends thereof are bent upward, and the position of the upper spring receiver 1c is set so that a lower restoring force is generated at both ends of the spring. Further, when the spring 11 is pushed down by the operation lever 10, the spring 11 comes into contact with the lower spring receiver 1b so that both ends of the spring 11 are lifted greatly upward, so that the separation claw 8 can be pressed against the stopper 1a with a predetermined force. The position of the lower spring bearing 1b is set to. The elastic force of the spring 11 is smaller than that of the torsion spring 2, and as will be described later, the recording paper 9
The elastic force is such that the separating claw 8 is lifted by the curl force of.

Next, the operation will be described.

When the recording paper 9 in the paper feed cassette 100 is exhausted and the paper feed cassette is taken out from the printer to set the recording paper, the hopper plate 3 is moved upward by the torsion spring 2 as shown in FIGS. Is pushed up, at this time, the rear end portion 10b of the operating lever 10 abuts against the pressing portion 3a of the hopper plate 3 and is lifted, and the abutment piece 10c separates from the spring 11. Therefore, the separation claw 8 is pushed up by bending both ends of the spring 11 upward, and the protruding portion 8g of the spring engaging portion 8f comes into contact with the stopper 1a (see FIGS. 8 to 10). 1a is not shown).

When setting the recording paper 9, the case lid 5
Open or remove the operation lever 10 as shown in FIG.
Is pressed from above. Then, the rear end portion 10b of the operating lever 10 pushes the pressing portion 3a of the hopper plate 3 to push down the hopper plate 3, and at the same time, the abutment piece 10c abuts and depresses against the spring 11, so that the spring 11 receives the lower spring bearing. The movement is regulated by coming into contact with 1b, the both ends are lifted, and the lifting force as shown by the arrow in FIG. Therefore, the separation claw 8 tries to rise, but is restricted by the stopper 1a and stays at the same upper limit position as in FIG. Since the spring 11 has a weak elastic force, the spring bends with a slight force. However, the large deflection of the spring presses the separating claw 8 against the stopper 1a with a large force, so that the separating claw 8 does not easily lower. This position can be retained.

Then, a predetermined number of recording papers 9 are inserted between the hopper plate 3 and the separating claws 8 and the hopper plate 3 is inserted.
Placed on top of the control lever 10 to release the pressing force,
As shown in FIGS. 5 and 10, the hopper plate 3 is subjected to the urging force of the torsion spring 2 and the spring 11 is separated from the lower spring bearing 1b by its restoring force, at the same time. Since the lower restoring force as shown by the arrow in FIG. 10 acts on both ends of the spring 11 by being regulated by the upper spring receiver 1c, the separating claw 8 makes elastic contact with the corner surface of the recording paper 9, and at the same time the protruding portion 8g The stopper 1a comes into contact with the stopper 1a to be in the upper limit thereof.

As a result, the recording paper 9 is set in the paper feed cassette 100, and the paper feed cassette is mounted in the printer for printing. As shown in FIG. 6, when the picking roller 12 is pressed against the uppermost recording paper 9 and is rotationally driven in the direction of feeding the recording paper forward, the recording paper 9 and the hopper plate 3 are pushed down. Along with this, the separation claw 8 follows the recording paper 9 by the restoring force of the lower side of the spring 11 and descends, and the protrusion 8g and the stopper 1a.
A predetermined gap is created between

Then, as shown in FIG. 7, when the uppermost recording paper 9 is fed forward by the rotation of the picking roller 12, the front end thereof comes into contact with the hook-shaped portion 8b of the separation claw 8 and advances further forward. The recording paper 9 begins to curl at that position. Here, the separation claw 8 receives the curl force of the recording paper 9 and ascends to the upper limit position where it abuts on the stopper 1a. As a result, a gap is formed between the separation claw 8 and the recording paper 9, the uppermost recording paper is curled surely, and is separated from the separation claw 8 before the curl becomes large,
It is sent to the print position.

After that, the uppermost recording paper 9 is separated and sent out by the separating claw 8 by the same action.

As described above, since the operation lever 10 is released when the recording paper 9 is fed out, the hopper plate 3 and the separating claw 8 operate independently of each other. That is, even if the hopper plate 3 rises as the recording paper 9 is used, the separation claw 8 does not rise in conjunction with it and is always at the predetermined position shown in FIG. 6, and as described in FIG. ,
Due to the curl of the recording paper 9, only the separation claw 8 is slightly raised,
As a result, the smooth feeding operation of the recording paper 9 is performed.

Although the operating lever 10 swings in the above embodiment, the operating lever may be of a slide type or the like.

Further, in the above embodiment, the piano wire is used as the spring 11, but the bar-shaped spring is not limited to a spring having a circular cross section, and various shapes such as a plate-shaped spring can be applied.

The means for elastically contacting the separation claw 8 with the surface of the recording paper 9 by the restoring force of the spring is not limited to the upper spring receiver 1c of the above embodiment.

Further, although the present invention is applied to the paper feed cassette in the above embodiment, the present invention can also be applied to a paper feed device or the like which is directly provided in the main body of the printer, copying machine or the like.

[0028]

As described above, according to the present invention, in addition to the urging means for urging the hopper plate upward, a pushing force is applied to the separating claw in association with the displacement of the operation lever for pushing down the hopper plate. As the separation claw holding mechanism, there are a bar-shaped spring in which the separation claws are engaged at both ends and the intermediate part is pushed down by the displacement of the operation lever, and a lower spring receiver in which the spring abuts from the upper side when the operation lever is displaced. Since the separation claw is provided, the separation claw can operate independently of the hopper plate when the operation lever is released.
The operation of sending out the sheets can be made smooth. Further, even if there is some variation in the manufacturing accuracy and the assembly accuracy of the hopper plate and the separating claw, the recording paper can be sent out smoothly as described above, so high manufacturing accuracy and assembly accuracy are not required. Low cost can be realized. Further, even if the manufacturing accuracy and the assembly accuracy of the separation claws are varied from side to side, this variation is absorbed by the deformation of the rod-shaped spring, so that no inconvenience is caused in feeding or setting the recording paper. Since the hopper plate is pushed down by the operating lever and the separation claw is pushed up in conjunction with this to open the space between them, the recording paper can be set very easily. Moreover, it has an excellent effect that it has a simple structure and is advantageous for downsizing of the device.

Further, since the upper spring receiver is provided, there is an excellent effect that the restoring force generated at both ends of the spring when the operating lever is released, that is, the elastic contact force with the surface of the recording paper can be easily set.

[Brief description of drawings]

FIG. 1 is a plan view of a paper feed cassette showing an embodiment of the present invention.

FIG. 2 is a partially cutaway enlarged view of the upper left portion of FIG.

FIG. 3 is a central cross-sectional view of FIG.

FIG. 4 is a cross-sectional view taken along the line AA in FIG. 2 and is a cross-sectional view in a state in which a recording paper is not set.

5 is a cross-sectional view taken along the line AA of FIG. 2 and is a cross-sectional view of a state in which the recording paper is set.

FIG. 6 is a cross-sectional view taken along the line AA in FIG. 2 and is a cross-sectional view in the initial state of the start of picking.

7 is a cross-sectional view taken along the line AA of FIG. 2 and is a cross-sectional view in a state where picking is performed.

8A and 8B show a procedure for setting recording paper in a paper feed cassette, and are a cross-sectional view and a front view around the operation lever in a state where the recording paper is not set, respectively.

9A and 9B show a procedure of setting a recording sheet in a sheet feeding cassette, and are a cross-sectional view and a front view around the operation lever in a state where the operation lever is pressed down, respectively.

10 (a) and 10 (b) show a procedure for setting recording paper in a paper feed cassette, and are a cross-sectional view and a front view around the operation lever in a state where the recording paper is set, respectively.

[Explanation of reference signs] 1b Lower spring receiver 1c Upper spring receiver 2 Energizing means (torsion spring) 3 Hopper plate 8 Separation pawl 9 Recording paper 10 Operating lever 11 Spring

Claims (2)

[Claims] 1. A hopper plate on which a recording paper is placed, an urging means for urging the hopper plate upward, and a top end which is in contact with a front end corner portion of the recording paper when the recording paper is sent out. Up and down movable separation claw for separating the recording paper, the operation lever that is displaceably supported and can push down the hopper plate against the urging force of the urging means, and interlock with the displacement of the operation lever. And a separation claw holding mechanism for applying a pushing-up force to the separation claw, wherein the separation claw holding mechanism has a rod shape in which the separation claw is engaged at both ends and an intermediate part is pushed down when the operation lever is displaced. And a lower spring receiver that is provided on both sides of the operation lever and is in contact with the spring from above when the operation lever is displaced. 2. The sheet feeding device according to claim 1, wherein upper side spring receivers are provided on both sides of the operation lever so that the spring contacts the lower side when the operation lever is released.