GB2151587A

GB2151587A - Sheet feeding apparatus

Info

Publication number: GB2151587A
Application number: GB08334247A
Authority: GB
Inventors: Ralph Edward Huckle
Original assignee: De la Rue Systems Ltd
Current assignee: De la Rue Systems Ltd
Priority date: 1983-12-22
Filing date: 1983-12-22
Publication date: 1985-07-24

Abstract

Sheet feeding apparatus comprises a pusher wheel (3) for feeding sheets from a stack (1) along a feed path past separation means. Separation means includes two pairs of surfaces defined by feed rollers (6) and separation rollers (11) which cooperate to define slits, forming part of the feed path, through which single sheets are fed. The feed roller (6) is movable to pass sheets along the feed path and the separation rollers (9) are movable at right angles to the feed direction. <IMAGE>

Description

SPECIFICATION Sheet feeding apparatus The invention relates to sheet feeding apparatus and particularly to apparatus for feeding banknotes.

One type of conventional sheet feeding apparatus is apparatus for counting the num ber of sheets in a stack while other apparatus may be used to test sheets in a stack for fitness, that is to examine the sheets for tears, folds and the like and to test the genuineness of the sheets particularly in the case of bank notes. In all these applications, it is necessary to ensure that sheets are fed singly'from a stack and in one known apparatus, sheets are fed into a gap between a feed roller and a separation block spaced a small distance from the feed roller. The gap is of such a size as to enable only single sheets to- pass through and thus separation of sheets is achieved. One of the problems with this apparatus is that the surface of the block facing the feed roller rapidly wears and this entails complete replacement of the block at comparatively frequent intervals.

In accordance with the present invention, sheet feeding apparatus comprises means for feeding sheets along a feed path past separation means, the separation means including at least one pair of surfaces which cooperate to define a slit, forming part of the feed path, through which single sheets are fed, one surface of'the or each pair of surfaces being movable to pass sheets along the feed path and the other surface of the or each pair of surfaces being movable transversely to the feed direction.

With this invention, the other surface of the or each pair of surfaces can be intermittently or continuously changed in order to ensure that any wear is evenly distributed without requiring disassembly of the apparatus.

Although the other surface could be formed by an endless belt, preferably the or each other surface is defined by the periphery of a separation roller or rollers respectively. The use of rollers simplifies construction and reduces the amount of space required by the separation means.

Conveniently, the other surface of the or each pair of surfaces conforms with the one surface in the feed direction. This assists the action of the separation means and in one particularly convenient example can be achieved when one or more separation rollers are used in'which case'the axes of the separation rollers are in alignment with the feed path direction.

Typically, the separation means will comprise two pairs of cooperating surfaces defin ing slits arranged side by side in'a direction perpendicular to the feed path in order to enable the separation means to separate wide sheets.

Preferably, the apparatus further comprises control means for moving the other surface of the or each pair of surfaces either continu only or in discrete'steps transversely to the - feed direction.

Some examples of sheet feeding apparatus in accordance with the present invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a partial cross-section taken on the line 1-1 in Fig. 2 through the separation means of one example; Figure 2 is a partial end-view, partially in section, of the separation means shown in Fig. 1;)and, Figure 3 illustrates schematically a second example of separation means.

The sheet feeding apparatus to be described is similar in all respects to conventional sheet feeding apparatus such as the De La Rue 2300 counting apparatus, except for the separation means. A pack of banknotes 1 is stacked on a stacking plate 2 positioned above a rotatable pusher wheel 3. The pusher wheel 3 has a lobe 4 which, on clockwise rotation of the wheel 3, as seen in the drawing, passes through an aperture 5 in the stacking plate 2 and pushes the lowermost banknote of the stack of notes 1 towards a pair of feed wheels 6 (only one shown in Fig.

1). Each feed wheel 6 has an annular recess 7.

Mounted in a housing 8 above the feedwheels 6 are a pair of separation rollers 9.

Typically, the housing 8 is made of pressure die cast zinc and the separation rollers 9 are made of plastics such as polyureythene in order to increase surface friction. Each separation roller 9 is mounted on a pivot 10 integrally formed with the housing 8, the pivot 10 being surrounded by plastics bushings 11.

As can be seen in Figs. 1 and 2, the pivots 10 extend in alignment with the direction of feed of the backnotes so that each separation roller 9 is rotatable about the pivots 10 in a direction at right angles to the feed direction.

Each separation roller 9 has a generally frustoconical form and extends into the respective annular recesses 7. The amount by which each separation roller 9 extends into the recesses 7 is determined in accordance with the thickness of the notes to be separated and can be adjusted by rotating eccentrics 1 2 in fixed slots 1 3 formed in a separate part of the apparatus housing 14.

Each plastics bushing 11 incorporates respective left and right handed ratchets 1 5. A plastics push button 1 6 is received in an aperture 1 7 n the housing 8 and is integrally formed with a pair of pawls 1 8 which engage respective ratchets 15; The push button 16 has a central 'bore 19 in which is provided a compression spring 20 which engages a part of the housing 8. When the push button 1 6 is depressed against the spring action, the pawls 1 8 will engage the ratchets 1 5 and cause the separation rollers 9 to rotate in the directions shown by arrows 20 (Fig. 2) to bring a fresh portion of the periphery of the rollers 9 opposite the feed rollers 6.On releasing the push button 16, the button will return to the position shown in Fig. 2 under the action of the compression spring 20.

A double non-return pawl 21 is also mounted to the housing 8 and engages the ratchets 1 5 to prevent the separation rollers 9 from rotating in directions opposite to those indicated by the arrows 20 and this ensures that the correct indexing action is achieved.

A cover plate 22 is mounted to the housing 8 to retain the push button 1 6 in position.

In operation, sheets are fed from the stack 1 under the action of the pusher wheel 3 into the slits between the separation rollers 9 and the corresponding feed rollers 6. The size of each slit is such that if more than one note is fed by the pusher wheel 3 the additional note or notes will engage the surfaces of the separation rollers 9 and will be prevented from passing between the separation rollers 9 and the feed rollers 6. Single notes that are fed between the slits are then carried by the feed rollers 6 towards further feed rollers (not shown) which carry the notes past conventional counting means and other detection apparatus.Periodically, the user can depress the push button 1 6 to index each separation roller 9 to bring a fresh portion of the surfaces of the separation rollers 9 opposite the feed rollers 6 in order to ensure that the surfaces of the separation rollers 9 wear evenly.

In a modified arrangement (not shown) the separation rollers 9 may be indexed automatically under the control of mechanical or electromechanical (solenoid) means either each time a new stack of notes is to be fed or after the passage of each note.

Fig. 3 illustrates a second example of the separation means in which the separation rollers 9 are continuously rotated. Instead of the plastics bushings 11 providing ratchets, each bushing 11 provides a gear 23. A pair of meshing gears 24 engage respective ones of the gears 23 and are driven by a worm gear 25 and worm wheel 26. The worm gear 25 is driven from the main drive system for driving the feed wheel 6 via a reduction gear system (not shown).

In operation, the separation rollers 9 are driven continuously at a very slow speed relatively to the speed of rotation of the feed roller 6. Typically, the rotation speed of the periphery of the separation rollers 9 will be in the range 0.5% to 1.0% of the linear speed of a note passing between the feed rollers 6 and separation rollers 9.

One advantage of this example in which the separation rollers 9 rotate continuously is that any centre creases in fed notes will tend to be smoothed out.

Claims

1. Sheet feeding apparatus comprising means for feeding sheets along a feed path past separation means, the separation means including at least one pair of surfaces which cooperate to define a slit, forming part of the feed path, through which single sheets are fed, one surface of the or each pair of surfaces being movable to pass sheets along the feed path and the other surface of the or each pair of surfaces being movable transversely to the feed direction.

2. Apparatus according to claim 1, wherein the or each other surface is defined by the periphery of a separation roller or rollers.

3. Apparatus according to claim 1 or claim 2, wherein the other surface of the or each pair of surfaces conforms with the one surface in the feed direction.

4. Apparatus according to at least claim 2, wherein the one surface of the or each pair of surfaces is formed by the periphery of a feed roller or rollers respectively, the periphery of the or each separation roller defining the other surface or surfaces having a frusto-conical form.

5. Apparatus according to any of the preceding claims, further comprising control means for moving the other surface of the or each pair of surfaces transversely to the feed direction in discrete steps.

6. Apparatus according to claim 5, wherein the control means comprises for the or each other surface a rachet and pawl arrangement.

7. Apparatus according to claim 5 or claim 6, wherein the outer surface of the or each pair of surfaces is moved transversely to the feed direction after the passage of each sheet between the surfaces.

8. Apparatus according to any of claims 5 to 7, further including means for automatically actuating the control means in response to the passage of a predetermined number of sheets.

9. Apparatus according to any of claims 1 to 4, further comprising control means to move continuously the other surface of the or each pair of surfaces transversely to the feed direction.

10. Apparatus according to claim 9, wherein the other surface of the or each pair of surfaces is continuously moved at a speed of between 0.5 and 1.0% of the speed of a sheet passing along the feed path.

11. Apparatus according to any of the preceding claims, wherein the other surface of the or each pair of surfaces is movable at right angles to the feed direction.

1 2. Sheet feeding apparatus substantially as herein described with reference to any of the examples illustrated in the accompanying drawings.