JPS638140A - Paper feeder - Google Patents

Abstract

PURPOSE:To perform the setting and sampling of paper in a simple manner as well as to keep off any variations in load in the point midway in the execution of secondary paper feeding, by installing a controlling device which controls a friction member driving member to select a pressure-contact state. CONSTITUTION:When paper is set onto a paper mount 4, it will do that a state of one side of engaging claws being engaged with a stopper 11e is merely selected, while a cam 11g is stopped in the state that an engaging projection part 11h is situated in the lowermost part, and a friction roller 3 is moved downward by a friction member driving part 9, whereby a lifting plate 5 can be rotated downward by a forward space control part 10. Therefore, if paper is set in this state, a tip of this paper comes into contact with a stopper part 1a. And, if a resist roller 12 is rotated and driven for secondary paper feeding, the paper is conveyable in the state that each load by a forward feed roller 7, a feed paper feed roller 2 and the friction roller 3 will not act utterly, and a high-grade transfer picture with no transfer slippage is secured.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a paper feeding device, and more specifically, the present invention relates to a paper feeding device. The present invention relates to a paper feeding device that transports sheets one by one.

<Prior art and points of inquiry to be solved by the defense> In copying machines, a paper feed cassette with a claw is used to feed sheets one by one, and a paper feed roller is used to feed sheets one by one. A paper feed cassette was used that applied conveying force to the paper stored in the paper feed cassette, but because of the claws, it was difficult to store the paper, and when feeding paper from the paper feed cassette, There is a problem in that claw marks are formed on the paper.

In order to eliminate such inconveniences and to make it applicable to stack bypass, etc., a paper feed device is provided that includes a forward feed roller that feeds the paper, a paper feed roller that is pressed against each other, and a friction roller. A paper feeding roller and a friction roller are provided to prevent double feeding and ensure feeding of one sheet at a time.

In a paper feeding device with such a configuration, if the paper feeding roller and the friction roller are kept in pressure contact with each other at all times, a jam may occur when the paper is held between the paper feeding roller and the friction roller. This results in a large load for removing the paper, which not only requires a great deal of force to remove the paper, but also causes the problem that, in the worst case, the paper may be torn.

Japanese Utility Model Application Publication No. 59-71230 is capable of solving the above-mentioned inconvenience, and is an ftf that applies a conveying force to the upper surface of a plurality of sheets of paper set in a stack bypass.
It has an f-feed roller, a paper feed roller that applies a conveyance force to the paper fed by the forward-feed roller and prevents double feeding, and a friction roller that has a built-in torque limiter. The paper feed roller and the friction roller are driven to rotate in the same direction, and the friction roller is coupled to the paper feed roller by a pressure release lever to which driving forces in opposite directions are applied by a solenoid and a spring. Selective control is performed between a closed pressure contact state and a pressure contact release state, and furthermore, a jam sensor drives a second solenoid.

Therefore, under normal conditions, sheets can be conveyed one by one by the action of the paper feed roller and the friction roller, and when a jam occurs, the friction roller can be separated from the paper feed roller to easily remove the paper.

However, since a solenoid and a jam sensor are required to separate the friction roller from the paper feed roller when a jam occurs, there is a problem in that the number of parts increases, causing an increase in cost.

In addition, under normal circumstances, when performing secondary paper feeding using registration rollers, if the paper is long, it will be in pressure contact with the paper feeding roller and friction roller at the beginning of the secondary paper feeding, so it will be difficult to transport the paper. This results in a state where a large load is applied. Then, after a certain amount of secondary paper feeding has been performed, the load caused by the paper feeding roller and the friction roller is rapidly relieved.

That is, the load changes significantly while the paper is conveyed by the register rollers, resulting in transfer misalignment and a reduction in image quality.

<Object of the invention> This invention was made in view of the above problems,
It is an object of the present invention to provide a paper feeding device that can easily set and remove paper regardless of the occurrence of a jam, and can prevent changes in load during secondary paper feeding.

Means for Solving the Problems> To achieve the above object, the paper feeding device of the present invention has the following features:
a detection means for detecting that paper has been conveyed to a position close to a registration roller that performs secondary paper feeding; a friction member driving means for selecting a state in which a friction member is in pressure contact with the paper feed roller and a state in which pressure is released; A forward feed control means that, in conjunction with the operation of the member driving means, selects a press contact state and a press release state between the paper and the advance roller, and a friction control means that selects a press contact release state when the registration roller performs secondary paper feeding. The apparatus includes a control means that controls the member driving means and also controls the friction member driving means to select a press contact state in a state in which the sheet is conveyed to a position where it is brought into contact with the registration roller.

However, the friction member may be a friction roller that is constantly rotated in the same direction as the paper feed roller.

Further, the friction member driving means and the forwarding control means both have driving force transmitted by the control means, and the control means has a clutch that is forcibly stopped when the control means has rotated by a required angle. It's okay.

With the paper feeding device configured as described above, when the paper is fed by the advance roller and the paper is conveyed one sheet at a time by the paper feeding roller that is pressed against the friction member, the paper feeder comes into contact with the registration roller. While conveying the paper to the position, the friction member drive means is controlled by the control means to select the pressure contact state.
n? 1' and controls the advance control means to select the pressure contact state, so that the advance roller applies a conveyance force to the paper, and the paper feed roller applies a conveyance force to the paper fed by the advance roller. At the same time, the friction member prevents double feeding and allows sheets to be conveyed one by one toward the registration rollers.

The detection means detects that the paper has been conveyed to a position close to the registration rollers, and after detecting the state in which the paper is in contact with the registration rollers based on this detection operation, the control means controls the friction member. The driving means and the advance control means are controlled to the opposite state to the above state, and the paper in contact with the registration rollers is in a free state, that is, in a state where no load is applied, and the transfer deviation is prevented by the registration rollers. It is possible to perform secondary paper feeding without having to use a benshi.

In addition, if the IIN friction member is a friction roller that is constantly driven to rotate in the same direction as the paper feed roller, when the secondary paper feed is performed, the second and subsequent sheets are It is possible to apply a conveyance force of 1,000,000,000, and prevent the first sheet from being conveyed following the first sheet.

Furthermore, the friction member driving means and the forwarding control means both have driving force transmitted by the control means, and have a clutch that is forcibly stopped when the control means has rotated by a required angle. In this case, the pressure contact state and the pressure release state are alternately selected by the friction member drive means and the advance control means every half rotation of the control means, so that the stop timing and The same effect as described above can be achieved by controlling the timing of forced stop cancellation in accordance with the paper conveyance timing.

<Example> Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

FIG. 1 is a vertical cross-sectional view of a main part showing an embodiment of a paper feeding device of the present invention, in which a paper feeding roller (2) is placed above a guide plate (1) that guides paper toward registration rollers (12). At the same time, a friction roller (3) is attached that moves upward through an opening (not shown) formed at a predetermined position of the guide member (1) and is brought into pressure contact with the paper feed roller (2+. The roller (3) is driven to rotate in the same direction as the paper feed roller (2).

An elevating plate (5) is rotatable in the vertical direction with respect to a paper tray (4) mounted at a predetermined position on the main body of the copying machine (not shown).
At the same time, the spring (6) lifts the lifting plate (5).
) is biased upward. Then, install the forward feed roller (7) at a position where it can come into contact with the upper surface of the lifting plate (5) in the upwardly biased state. A guide flange (8a) is attached to the shaft, and a guide member (8) for preventing upward movement of the paper is formed integrally with the guide flange (8a) marked -.

Further, an elevating plate (5) is provided on the upstream side of the guide member (1).
forms a stopper portion (1a) that receives the leading edge of the paper in a downwardly rotated state. In addition, (5a) is the elevating plate (
5), and (13) is the rotation axis of the registration roller (12).
) is a paper detection switch as a detection means, which is provided on the slightly upstream side of the paper.

Referring also to FIG. 2, a friction member drive unit (9) that raises and lowers the friction roller (3), an advance control unit (g) that rotates the elevating plate (5), and the friction member drive unit ( 9) and the control section (11) that controls the feed control section (g)) will be explained in detail.

The L notation part (11) is a cylindrical body (11) that rotates in one direction with a gear (11a) that is rotationally driven by a drive source (not shown).
b), engagement claws (11c) at positions 180 degrees apart from each other and a predetermined distance apart in the axial direction.
(11d) is formed. Then, the engagement claw (11C) (lid
) and a stopper (11e) that can be selectively engaged with the stopper (11e). Further, a shaft (
Attach the cam (11(+) to the cam (11(+)) (push) to the cam (11(+)).The cylinder body (11b) and gear (11a) should not slip when one of the engagement claws is engaged with the stopper (11e). I try to do that.

The friction member drive section (9) has a long hole (9b) formed at the other end of the link (9a), one end of which is connected to the engagement protrusion (11h) of the cam (11()). The bearing (3a) loosely inserted into the shaft of the friction roller (3) and the elongated hole (9)
b) are engaged with each other. And the above bearing (3a)
A pressure spring (9C) is installed between the
is the mounting number.

The forward feed control section (g)) has a long hole (10b) in the other end of the link (10a), one end of which is connected to the engagement protrusion (11h) of the cam (11()). The engaging portion (5a) formed at a predetermined position of the culm plate (5) is engaged with the elongated hole (10b).

The operation of the above-mentioned @formation feeding device is as follows.

When setting paper on the paper table (1), it is sufficient to select a state in which one of the engagement claws is engaged with the collar (11e), and the cam (11g) is engaged with the engagement protrusion f11h. ) is at the lowest position +H, friction member drive unit (9)
While moving the friction roller (3) downward,
The forward feed control section (rotation) can rotate the four descending plates (5) downward. Therefore, if paper is set in this state, the leading edge of the paper will come into contact with the stopper portion (1a).

After the paper has been transferred to the cellar 1 as described above, when carrying out the paper conveyance operation, it is sufficient to first select a state in which the other engagement claw engages with the stopper (11e), and then the cam ( 11o) stops with the engagement protrusion (11h) located at the uppermost position, moves the friction roller (3) to one side by the friction member drive unit (9), and moves the flfi feed control unit (g)) The lifting plate (5) can be rotated upward. Therefore, in this state, the forward feed roller (7) rotates to apply a conveyance force to the uppermost sheet of paper, causing the paper to move toward the paper feed roller (2), and then the paper feed roller (2) A conveying force in the direction can be applied. However, in this case, the paper feed roller (
2) and the friction roller (3) are in pressure contact and driven to rotate in the same direction, so even if two or more sheets of paper are being fed, the conveying force is reliably applied to only the topmost sheet. This can prevent double feeding. Further, since the friction roller (3) has a built-in torque limiter, if only one sheet of paper is fed, it will be rotated in the opposite direction to the paper feed roller (2).

Next, the paper is detected by the paper detection switch (13), and when the leading edge of the paper comes into contact with the registration roller (12) after a predetermined period of time has elapsed, one of the engagement claws is moved again to the stopper (12). 11e). In this selected state, the cam (11g) is connected to the engagement protrusion (11h).
) is stopped at the lowest position, the friction member drive unit (9) moves the friction roller (3) downward, and the forward feed control unit (g)) rotates the lifting plate (5) downward. can be moved. That is, the forward feed roller (7)
At the same time, the friction roller (3) is in a state where it cannot apply any conveying force to the paper, and the friction roller (3) is in a state where the paper is held between it and the paper feed roller (2), resulting in a blank state.

Therefore, in order to perform secondary paper feeding, the registration roller (
12), it is possible to transport the paper without any load from the advance roller (7), paper feed roller (2), and friction roller (3), resulting in high quality transfer without misalignment. The transferred image can be removed.

In this state, the rotation of the friction roller (3) applies a slight force in the opposite direction to the feeding direction to the paper whose feeding is prevented by the friction roller (3), so that the paper is prevented from being fed out by the friction roller (3). It is possible to reliably prevent the inconvenience of the second and subsequent sheets of paper following and moving due to frictional resistance.

After that, the paper detection switch (13) detects the trailing edge of the paper, and when a predetermined time has elapsed, the stopper (11)
e) is brought into engagement with the engaging claw of the user, and the above paper feeding operation can be repeated.

FIG. 3 is a vertical cross-sectional view of a main part showing another embodiment, and the difference from the embodiment described above is that the -@ portion is connected to the shaft of the friction roller (3), and the other end is connected to the forward feed roller. The central part of the arm (14) connected to the shaft of (7) is rotatably connected to a predetermined position on the main body of the copying machine, and one end is connected to the cam (11 (1)).
The only point is that the link (15) is rotatably connected to the engaging protrusion (11h) and the other end is connected to the shaft of the forward-feeding "1-ra (7)". In this embodiment, the friction member drive section (9) and the advance control section (g) are integrally constructed.

Therefore, also in this embodiment, the stopper (11e
) can be selectively and sequentially engaged with the engaging pawls, it is possible to feed sheets one by one as in the above embodiment, and the registration rollers (12 ), it is possible to reliably prevent the occurrence of transfer misalignment in the secondary paper feeding state.

Note that the present invention is not limited to the above-described embodiments; for example, it is possible to use a friction pad in place of the friction roller, and it is also possible to use a document feeder 1 and a paper feed cassette that does not have a claw. In addition, it is also possible to configure the friction member drive section, J pump, and advance control section with solenoids, and various other design changes can be made without changing the gist of the present invention. It is possible to apply

<Effects of the Invention> As described below, this invention brings the friction member into pressure contact with the paper feed roller only when the paper is conveyed until it comes into contact with the registration roller, and also brings the advance roller into pressure contact with the topmost paper. This makes it possible to reliably transport sheets one by one, and in addition, when secondary paper feeding is performed using registration rollers, unnecessary loads caused by advance rollers and friction members are completely removed. This has the unique effect of allowing secondary paper feeding to be performed without causing transfer misalignment.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of essential parts showing one embodiment of the paper feeding device of the present invention, FIG. 2 is a schematic perspective view showing a control section and a friction member driving section, and FIG. 3 is a diagram showing another embodiment. Main part longitudinal sectional view.

Claims (1)

[Claims] 1. Feed the paper with the advance roller and rub it. Used by the paper feed roller that comes into pressure contact with the rubbing member. A paper feeder that transports paper one sheet at a time. A register that allows secondary paper feeding The paper is transported to a position close to the stroller. detection means for detecting that the The state of pressure of the rubbing member against the paper feed roller, Friction member drive hand that selects pressure release state The stage is interlocked with the operation of the friction member drive means. The state of pressure contact between the paper and the advance roller, Advance control means for selecting pressure release state and performs secondary paper feeding using registration rollers. In order to select the pressure release state in the While controlling the friction member driving means, For use up to the position where it touches the registration roller. Select the pressure contact state when transporting paper. A control for controlling the friction member drive means to select A supply system characterized by having control means. paper equipment. 2. The friction member is aligned with the rotation direction of the paper feed roller. A friction roller that is constantly driven to rotate in the same direction. Paragraph 1 of the above claim, which is Includes paper feed device. 3. Friction member drive means and advance control Transmission of driving force by both means and control means control means are in place. Forcibly stop after rotating the required angle. The above has a clutch that A paper feeding device according to claim 1.