JPH0122183B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a paper feeding mechanism for a device that processes paper sheets as a medium, and the present invention relates to a paper feeding mechanism for a device that processes paper sheets as a medium. The invention relates to a paper feeding mechanism that automatically performs basic operations such as taking out, feeding, counting, recognizing, and storing paper sheets continuously until there are no more paper sheets in the hopper.

[Prior art] The paper sheets stored in the hopper are separated one by one,
Various paper feeding mechanisms have been developed in the past, but the paper feeding mechanism shown in Figures 1 and 2 is a general and simple mechanism that feeds sheets of the same thickness. It is widely known as a thing.

To explain its structure, in FIG. 1, 1 is a hopper, 2 is a plurality of sheets of paper stored in the hopper 1, 3 is a weight plate set on the paper sheets 2, and 4 is a pick-up roller. , this pick-up roller 4 is positioned so that the weight plate 3 and the weight of the sheet 2 act most effectively on the hopper 1.
is installed at the bottom of the

Reference numeral 5 denotes a paper feed port provided in the hopper 1 so as to be located on the front edge (right end in the figure) side of the paper sheet 2. Near the outside of this paper feed port 5, there is a paper feed port located near the front edge of the paper sheet 2 (right end in the figure). A paper feed roller 6 that rotates in the forward direction and a separation roller 7 that rotates in the opposite direction are placed facing each other in a positional relationship that will be described later.

That is, as shown in FIG.
One or more grooves 6a are provided on the outer circumferential surface of the separating roller 7, and correspondingly, protrusions 7a are provided on the outer circumferential surface of the separating roller 7, and the overlapping amount δ shown in FIG. Only the groove 6a and the protrusion 7a
are interlocking. Note that the paper feed roller 6 may be provided with a protrusion, and the separation roller 7 may be provided with a groove.

Further, the friction coefficient between the outer peripheral surface of the paper feed roller 6 and the paper sheet 2 is μ ₁ , the friction coefficient between the protrusion 7a of the separating roller 7 and the paper sheet 2 is μ ₂ , and the friction coefficient between the paper sheets 2 is μ ₃ , the surface members of the paper feed roller 6 and the separation roller 7 are set to satisfy μ ₁ >μ ₂ >μ ₃ (1).

In this configuration, the sheets 2 accumulated and stored in the hopper 1 are pressed against the pick-up roller 4 by a pressing mechanism such as a weight plate 3 or a spring, and are pushed to the bottom by the auxiliary feed force generated by the rotation of the pick-up roller 4. One or more sheets of paper 2 are fed out from the paper feed port 5 of the hopper 1 and enter the meshing portion between the paper feed roller 6 and the separating roller 7. Then, as shown in FIG. 2, these sheets 2 are squeezed by the mechanism 6a of the paper feed roller 6 and the protrusion 7a of the separation roller 7, and the difference in frictional force generated by the above equation (1) is As a result, only one sheet 2 in contact with the sheet feeding roller 6 is separated from the other sheets 2, and is fed and conveyed in a predetermined direction.

However, in such a conventional paper feeding mechanism, when the surface members of the paper feeding roller 6 and separation roller 7 wear out, the overlap amount δ changes and double feeding occurs, and also due to changes in temperature conditions. A phenomenon occurs in which the coefficient of friction between the surface members of the paper feed roller 6 and the separation roller 7 changes, and the equation (1), which defines the difference in the coefficient of friction for separating the paper sheets 2, no longer holds.
This method has the disadvantage of causing double feeding or paper feeding failure.

In addition, the effect of the separation roller 7 for separating the paper sheets 2 fed out from the hopper 1 by the pick-up roller 4 one by one is concentrated for a short time, that is, at the meshing part at the apex of the rollers. Condition 2, i.e. changes in thickness, adhesion between paper sheets,
Another drawback is that it has a poor ability to follow changes in the condition of the leading edge of a sheet, and is therefore unreliable.

[Structure of the invention]

The present invention was made in order to solve the above-mentioned drawbacks of the prior art, and it is possible to separate paper sheets one by one when the surface members of the paper feed roller and separation roller wear out or the temperature changes. It is an object of the present invention to realize a paper feeding mechanism that can reliably feed paper, can follow changes in the thickness of paper sheets, and can improve reliability.

[Summary of the Invention] In order to achieve the above-mentioned object, the present invention makes it possible to move a separating roller installed opposite to a paper feed roller, and also includes an adjusting means for moving the position of the separating roller. A driving means for operating this adjustment means is provided, and data on contradictory events such as "abnormal double feeding" and "unable to feed" is sampled for each feeding operation for one sheet, and feedback is provided each time. The adjusting means adjusts the position of the separating roller, thereby adjusting the amount of overlap between the paper feed roller and the separating roller for feeding one sheet;
This ensures that the balance of frictional forces is always maintained at an optimum level.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 3 is a schematic side view showing one embodiment of the paper feeding mechanism according to the present invention, in which 1 is a hopper, 2 is a sheet of paper, 3 is a weight plate, 4 is a pick-up roller, 5 is a paper feed port, and 6 1 is a paper feed roller, and 7 is a separation roller, which correspond to those shown in FIG. 1 and are designated by the same reference numerals.

Although this embodiment is an example in which the circumferential length of the paper feed roller 6 is longer than the length in the feeding direction of the target paper sheet 2, the present invention is not limited to this.

In addition, in this embodiment, a part of the surface of the paper feed roller 6 is given a material and shape that has a high coefficient of friction against the paper sheet 2 by the central angle θ, and the paper sheet in this part (hereinafter referred to as high friction part) 6b is The friction coefficient for 2 is μ ₁ θ,
The coefficient of friction between the circumferential surface of the 2π-θ part and the sheet of paper is μ ₁ (2π-θ), the coefficient of friction between the surface of the separating roller 7 and the sheet of paper 2 is μ ₂ , the coefficient of friction between the sheets of paper 2 Assuming that μ ₃ , each surface member is set so that the following formula holds true.

μ ₁ θ＞μ ₂ >μ ₃ >μ ₁ (2π−θ)……(2) Also, μ ₀ is the coefficient of friction between the surface member of the pick-up roller 4 and the paper sheet 2, and the load pressed by the pick-up roller 4 is Assuming that W is the pressure acting on the paper sheet 2 that has entered between the paper feed roller 6 and the separation roller 7, then the feed force that attempts to feed the paper sheet 2 is expressed by the following equation.

Wμ ₀ +Pμ ₁ θ＞Pμ ₂ >Wμ ₀ +Pμ ₁ (2π−θ) ...(3) Therefore, select the friction coefficient μ ₀ of the surface member of the pick-up roller 4 and make sure that the pressure P satisfies equation (3). The amount of overlap δ between the paper feed roller 6 and the separation roller 7 is determined so that the paper feed roller 6 and the separation roller 7 fall within the range.

Further, as can be seen from the above equations (2) and (3), in this embodiment, only when the high friction portion 6b of the paper feed roller 6, which has the highest friction coefficient and the strongest feeding force, comes into pressure contact with the paper sheet 2, The paper sheets 2 are fed separately.

Reference numeral 8 denotes a shaft provided at the center of the paper feed roller 6, and the shaft 8 rotates the paper feed roller 6 in the vertical direction, that is, in the forward direction with respect to the traveling direction of the paper sheet 2. The pick-up roller 4 is also rotated in the same direction as the paper feed roller 6 by a shaft 9.

On the other hand, in this embodiment, the separation roller 7 is held by a support shaft 10, and is given a degree of freedom to rotate relative to the support shaft 10 by a bearing. This support shaft 10 is supported by a bracket 11, and the bracket 11 is rotatably attached to a drive shaft 13 via a bearing 12, and a pulley 14 is fixed to the drive shaft 13. Power is transmitted from the belt 14 to a pulley portion (not shown) of the separation roller 7 via a belt 15.

A clockwise rotational force is applied to the drive shaft 13 by a power source (not shown), thereby causing the separation roller 7 to rotate in the same direction.

Further, the bracket 11 has a fixed support body 16.
A clockwise torque about the drive shaft 13 is applied by a spring 17 crimped between It was accepted at age 19. That is, this screw shaft 19 is an adjustment means for adjusting the position of the separation roller 7 by rotation of the bracket 11, and its lower end is connected to the support shaft 10 of the separation roller 7.
By bringing the separation roller 7 into contact with the separation roller 7, movement of the separation roller 7 is prevented.

Approximately half of the screw shaft 19 is a non-threaded part, and a fixing screw 2 is installed at the top of the non-threaded part.
0, a gear 21 is fixed, and a gear 22 meshing with this gear 21 is fixed by a fixing screw 25 to a rotating shaft 24 of a pulse motor 23 attached to the fixed frame 18 as a driving means for the screw shaft 19. ing.

Here, since the screw shaft 19 has a right-handed thread, when the pulse motor 23 is rotated clockwise when viewed from the axial direction, the screw shaft 19 rotates and moves downward, and the separation roller 7 is pushed down, and the amount of overlap δ with the paper feed roller 6 increases. Conversely, pulse motor 23
When the screw shaft 19 is rotated counterclockwise, the screw shaft 19 rotates and rises, whereby the separation roller 7 is pushed up by the torque of the spring 17, and the amount of overlap δ is reduced.

Further, a driver groove 19a is provided at the upper end of the screw shaft 19, and if the screw shaft 19 is rotated by a driver using this driver groove 19a and the separation roller 7 is moved, the overlapping can be performed manually. It is also possible to adjust the amount δ.

Reference numeral 26 denotes a fixed bracket, and a light emitting diode 27 and a light receiving diode (not shown) facing the light emitting diode 27 with the paper feed roller 6 in between are fixed to the fixed bracket 26. Only when the through hole 28 provided in the paper roller 6 moves onto the optical axis, light is received by the light receiving diode, and thereby the number of rotations of the paper feed roller 6 is counted.

Reference numerals 29 and 30 denote guide plates for guiding the sheet 2 after passing through the meshing portion between the paper feed roller 6 and the separation roller 7. The guide plates 29 and 30 have through holes 31 and 32 are provided. A light-emitting diode 33 and a light-receiving diode 34 are disposed opposite to each other on the outside thereof, and each time a sheet 2 passes, the optical axis is interrupted and the number of passages of the sheet 2 is counted. Further, while the paper sheet 2 blocks the optical axis, the output light of the light emitting diode 33 is reflected and absorbed by the paper sheet 2, but the transmitted light irradiates the light receiving diode 34 at a certain rate. Since this transmitted light is further attenuated when the paper sheets 2 are abnormally double fed, the light emitting diode 33 and the light receiving diode 34 can also identify the abnormal double feeding.

Note that the abnormally double-fed paper sheets 2 are removed by normal processing using a switching valve or the like (not shown), but since this is not directly related to the present invention, a description thereof will be omitted.

Reference numerals 35 and 36 denote through holes provided at the front and bottom of the hopper 1. A light emitting diode 37 and a light receiving diode 38 are placed facing each other with the through holes 35 and 36 in between. The presence or absence of leaf 2 can be detected.

FIG. 4 is a flowchart showing the operation of the paper feeding mechanism with the above-described configuration, and 39 in the figure is a set number of times to suck in one sheet of the same sheet 2;
42, the light emitting diode 27 and the light receiving diode opposite thereto open the through hole 2 of the paper feed roller 6.
This is used for the purpose of detecting an abnormal state by comparing the number of retries at 52, which is incremented by 1 at 51 each time 8 is detected, and performing alarm processing at 54. In 49 and 50, the pulse motor 2 with one try was confirmed in advance by experiment.
It rotates by a predetermined number of steps of 3. Further, 53 is a part that uses the light emitting diode 3 and the light receiving diode 38 to determine whether or not there is a paper sheet in the hopper 1, and the paper sheet 2 is processed according to the procedure of the flowchart shown in FIG. be done.

〔Effect of the invention〕

As explained above, the present invention makes it possible to move the separation roller arranged opposite to the paper feed roller, and to separate the paper sheets one by one. Since the feedback control process is performed using conflicting data such as ", the separation state that is most suitable for the paper sheets to be fed, that is, the optimal amount of overlap between the paper feed roller and the separation roller, can always be automatically adjusted. Therefore, it is possible to sufficiently cope with changes in the coefficient of friction due to wear of the surface members of the paper feed roller and the separation roller and changes in temperature, and there is an effect that reliable paper feeding can be performed.

In addition, it is possible to sufficiently follow changes in the thickness, hardness, softness, etc. of paper sheets, and has the effect of improving reliability.

As described above, since the present invention has a highly reliable separation and paper feeding mechanism, it can be used not only for equipment that processes paper sheets such as documents, forms, and cards, but also for automatic deposit processing machines that handle banknotes, and automatic withdrawal machines. It can be widely used as a paper feeding mechanism for metal machines, counting machines, etc., and can exhibit sufficient performance as a future device where maintenance cycles tend to be longer.

[Brief explanation of drawings]

Fig. 1 is a schematic side view showing a conventional paper feeding mechanism, Fig. 2 is a front view of the paper feeding roller and separating roller in Fig. 1, and Fig. 3 shows an embodiment of the paper feeding mechanism according to the present invention. A schematic side view, FIG. 4 is a flowchart showing the operation. 1... Hopper, 2... Paper leaf, 4... Pick up roller, 5... Paper feed slot, 6... Paper feed roller, 6
a...Groove, 6b...High friction part, 7...Separation roller, 7a...Protrusion, 10...Support shaft, 11...Bracket, 13...Drive shaft, 14...Pulley, 1
5...Belt, 17...Spring, 18...Fixed frame, 19...Screw shaft, 23
...Pulse motor, 27, 33, 37... Light emitting diode, 34, 38... Light receiving diode, 2
8, 31, 32, 35, 36... through hole.

Claims (1)

[Scope of Claims] 1. A plurality of sheets of paper stored in a hopper are fed out by a pick-up roller provided at the bottom of the hopper, and the fed out sheets are faced to a paper feed roller and the paper feed roller. In a paper feeding mechanism that separates and feeds paper sheets one by one by entering the meshing portion with a disposed separation roller, the amount of overlap of the meshing portion with respect to the paper feeding roller increases or decreases. a rotatable bracket that supports the separation roller so that it can move in the direction; a screw shaft that moves the separation roller to adjust the amount of overlap; and a screw shaft that adjusts the amount of overlap when sheets cannot be fed. The screw shaft is driven so that the separating roller moves in a direction that increases the amount of overlap, and when multiple sheets are fed, the screw shaft is driven so that the separating roller moves in a direction that decreases the amount of overlap. A paper feeding mechanism characterized by comprising a driving means for driving.