GB2200891A - Particulate material dispenser - Google Patents

Abstract

A device for dispensing particulate material into cups for subsequent use in a vending machine has two dispensing nozzles (34), through a cylindrical bore of each of which passes a respective screw auger (42) having a disc (50) secured to its lower end. The exterior of each nozzle (34) is shaped to receive a cup (54) whose upper rim is adapted to abut substantially sealingly against a shoulder (58) provided on the nozzle. The cups (54) are liftable into engagement with the shoulders (58) around the nozzles (34) by means of pneumatic jacks (56) situated beneath the cups. In use, a conveyor (22) advances the cups stepwise so that each in turn is situated beneath a nozzle. The jacks (56) are then actuated to position the cups (54) around the respective nozzles (34) with the upper rims of the cups in contact with the respective shoulders (58) on the nozzles. Rotation for a predetermined time of the augers (42) causes a metered amount of particulate material to be advanced along the cylindrical bores (38) onto the discs (50), from which the material is thrown-off by centrifugal force. <IMAGE>

Description

PARTICULATE MATERIAL DISPEN5ER.

The present invention relates to particulate material dispensers, and in particular, but not exclusively, to dispensers for dispensing powder into cups for drink vending machines.

In many drink vending machines, the cups are arranged in a stack within the machine and are dispensed individually upon insertion of appropriate coins in the machines. Each cup in the stack already has the necessary solids, e.g. coffee powder, coffee whitener and the like, situated within it so that the addition of hot water to the cup frva a dispenser operated by the purchaser makes the drink in the cup.

It is thus necessary to have the ingredients in each cup before the cups are stacked. Existing devices for dispensing the ingredients comprise a vertically disposed helical auger rotatable within a cylinder conduit. The upper end of the auger and aperture extend into a small hopper which is fed with the material to be dispensed, such that rotation of the auger causes the material to be fed down the cylinder. A disc is secured to the lower end of the auger and extends across the lower end of the aperture. The disc is therefore arranged to rotate with the auger. The result is that when no rotation of the auger and the disc occurs no material can fall from the end of the cylinder by gravity, but when rotation of the auger and disc does occur the material fed by the auger onto the disc is thrown off by the centrifugal effect.The material is collected by a funnel which shrouds the disc and directs the material onto a knife edge where the material is divided between two bifurcating chutes and hence into two cups waiting underneath on a conveyor which has been advanced stepwise to position the cups beneath the outlet of the respective chutes.

By controlling- the number of turns of the auger, the approximate amount of material dispensed into each cup may be determined. The amount dispensed into each cup is only roughly the same, since it is impossible to direct exactly half the material dispensed from the auger into each of the two chutes, resulting in inconsistent strengths of drinks from the vending machine.

Moreover, the provisions of the knife edge and the two separate chutes results in a relatively long fall for the material, which tends to produce clouds of very fine particles of material dust, which can find its way into machinery and which may necessitate the use of face masks by those in the vicinity of the dispenser.

It is an object of the present invention to provide a device for dispensing particulate materials, which device produces less dust than known devices.

In accordance with a first aspect of the present invention, a particulate material dispenser comprises material dispensing means, a dispensing nozzle through which the material is dispensed, the dispensing nozzle being shaped to be received by a receptacle into which the material is to be dispensed, and displacement means adapted to displace the receptacle relative to the nozzle whereby during dispensing-of the material the receptacle at least partially surrounds the dispensing nozzle.

Preferably, the receptacle abuts a portion of the dispensing nozzle, and in a preferred embodiment, a shoulder, against which the receptacles abut, is provided on the nozzle.

The displacement means may comprise a fluidoperating ram.

The device may further comprise a conveyor for conveying a succession of receptacles into which the material is to be dispensed. The conveyor is preferably movable stepwise to position each receptacle in turn beneath the nozzle.

There may be a plurality of dispensers as hereinbefore described.

In one embodiment, the device comprises two dispensers arranged side-by-side and a conveyor beneath the dispensers adapted to advance two rows of receptacles towards the respective nozzles.

In accordance with a second aspect of the present invention, a particulate material dispensing device comprises a plurality of dispensing means, each dispensing means being provided with a single dispensing nozzle through which the material is dispensed.

In contrast with the prior art, wherein a single dispenser dispenses material into two nozzles, the dispenser in accordance with the present invention results in a short path from the dispensing means to the receptacle, resulting in a reduction in the amount of dust produced. Furthermore, providing each dispenser with its own, single dispensing nozzle results in a more accurate amount of material being dispensed from the nozzles.

In one embodiment, each dispensing device is in the form of an auger housed within a cylindrical conduit. Preferably, a disc is provided at the baseof each auger, the disc being arranged to be rotatable with the auger.

Preferably, the auger and/or the disc extend into the dispensing nozzle.

In accordance with a third aspect of the present invention, a particulate material dispensing device comprises material dispensing means and a nozzle through which the material is dispensed, the nozzle being shaped such that the material dispensed therefrom assumes a convergent shape.

This tends to keep the material being dispensed more concentrated, thereby reducing the amount of dust produced.

Preferably, the material converges to a neck and then diverges.

By way of example only, a specific embodiment of the present invention will now be described, with reference to the accompanying drawings, in which: Fig.l is a perspective view of an embodiment of particulate materials dispenser in accordance with the present invention; Fig.2 is a detail perspective view of the dispensing nozzles of the dispenser illustrated in Fig.l; and Fig.3 is a cross-section through the dispensing nozzles of the dispenser illustrated in Fig.l.

The dispenser comprises an electric motor drive unit 10 which drives a gearing unit 12, consisting of pulleys and belts, to reduce the speed from the electric motor to a suitable speed. A dispensing unit 14 extends downwardly from the underside of the gearing unit. The dispenser is mounted on a support leg 16 which projects upwardly from a base plate 18 which extends across a cup conveyor 20. The cup conveyor comprises a plurality of hinged plates 22, each plate being provided with two circular apertures 24 which are each shaped so as to allow a cup to pass therethrough but to be supported on the plate by engagement of a peripheral rim on the cup, the rim being of greater diameter than the apertures. The conveyor is movable stepwise in an endless path, each step positioning two cups beneath the dispensing unit 14.

The dispensing unit 14, illustrated in more detail in Figs. 2 and 3 comprises a hopper 26 which is supplied with particulate material through a tube 28 inclined thereto. A flexible supply conduit 30 (illustrated schematically in Fig.l) supplies the material to the tube 28. The hopper 26 is mounted on a cuboidal base 32 which has two, downwardly tapering, frusto-conical apertures 33. Two tapered dispensing nozzles 34 extend downwardly from the underside of the base 32, and are illustrated in more detail in Fig.3.

Each nozzle 34 has an upper, solid portion 36 having frusto-conical outer walls and an inner, vertically disposed, cylindrical bore 38, a lower hollow chute portion 40 whose outer walls are contiguous with the outer walls of the upper portion and whose inner walls are also frusto-conical and downwardly tapered. The outer walls of the nozzle are shaped to be received in a cup, as will be explained.

An auger 42 is disposed in each of the cylindrical bores 38 and is a close fit therein, and also extends into a respective conical aperture 33. The auger comprises a helical blade 44 disposed on a rotatable tubular shaft 46 and extends out of the upper and lower ends of the cylindrical bore. A stirring member 48 is positioned in each frusto-conical aperture 33 and comprises a downwardly extending arm 49 having an inwardly inclined and tapering end portion 49a. The end of the arm 49 remote from end 49a is mounted on a member (not shown) which is rotatable concentrically with the shaft 46 and auger 42, such that the arm 49 and arm end 49a perform an orbital motion about the shaft 46.The arm 49 is arranged such that it orbits only when the shaft 46 rotates, but the arm 49 is arranged to orbit at one tenth the speed of the shaft 46 suc that the shaft 46 rotates ten times for every orbit of the arm 49. In this way, the stirrer gently agitates the material to be dispensed, and prevents it from becoming clogged. The arm 49 and end 49a are curved so that they are slightly spaced apart from the walls of the frusto-conical aperture 33.

The nozzles 34 are situated slightly above the level of the conveyor 20 which normally holds cups 54 in the position A-(illustrated in chain dot), with the upper, peripheral rims of the cups resting on the conveyor. The conveyor is advanced forward stepwise such that two cups are situated directly beneath respective dispensing nozzles. When the conveyor is temporarily stopped in this position, the cups are lifted by respective pneumatic jacks 56 into the position B (shown in chain dot) wherein the peripheral rim of each cup abuts an annular shoulder 58 provided around each nozzle. The pneumatic jacks (illustcated schematically in Fig.3) each comprise a pneumatic cylinder 60, a piston (not visible) movable therein, a piston rod 62 attached to the piston and a circular plate 64 attached to the end of the rod 62.By actuating the jack the plate 64 is moved upwardly, thus engaging with the cup and lifting it into position B.

In use, the apparatus is switched on and the conveyor advances and stops with two cups positioned vertically beneath the nozzles. When the conveyor stops in this position, the jacks 56 are actuated, lifting the cups into position B. When the cups are in position, the auger is actuated and rotates for a predetermined number of rotations, thereby advancing a predetermined amount of material from the hopper 26 through the bore 38. As the auger rotates, the dispensing disc 50 rotates with it, thereby throwing outwardly the material advanced by the auger from the hopper, and causing it to be dispensed into the cup 54 positioned below, guided by the nozzle 40. As illustrated in Fig.3, the material dispensed is guided by the nozzle into a narrow neck 62 of material which then diverges. This keeps the material more together, and reduces the formation of unwanted dust.The abutment of the rim of each cup with-its respective shoulder 58 also keeps any dust dispensed from the device to a minimum. Also, the relatively small volume enclosed by the nozzle and the cup surrounding the nozzle and the short path of the material from the auger to the cup reduces the amount of dust produced, and the short path also makes the dispensing of the material virtually instantaneous, so that it is not necessary to hold the cup in position for a long time while the material makes its way to the cup. As mentioned previously, as the augers rotate, the stirrers 49 gently agitate the material to be dispensed.

Once the required amount of material has been dispensed (dependent upon the number of turns of the auger) the jacks 56 are operated in reverse, so that the cups 54 are once again positioned on the conveyor plate 22. The conveyor 20 is then advanced and the cycle is repeated.

The cycle is carried out automatically so that no human operation, other than to start the device, is required.

Moreover, the illustrated embodiment shows a device with two dispensing nozzles, but it is envisaged that three or more nozzles, each with its own dispensing means, could be used, with an appropriate alteration to the conveyor 20.

Claims (23)

1. A particulate material dispenser comprising material dispensing means, a dispensing nozzle through which the material is dispensed, the dispensing nozzle being shaped to be received by a receptacle into which the material is to be dispensed, and displacement means adapted to displace the receptacle relative to the nozzle whereby during dispensing of the material the receptacle at least partially surrounds the dispensing nozzle.

2. A dispenser as claimed in claim 1, wherein during dispensing of the material, the receptacle abuts a portion of the dispensing nozzle.

3. A dispenser as claimed in claim 2, wherein the receptacle abuts a shoulder provided on the nozzle.

4. A dispenser as claimed in claim 2 or claim 3, wherein a rim of a receptacle abuts a portion of the dispensing nozzle substantially sealingly.

5. A device as claimed in any of claims 1 to 4, wherein each dispensing means comprises an auger housed within a cylindrical conduit.

6. A device as claimed in claim 5, further comprising a disc at the base of each auger, the disc being arranged to be rotatable with the auger.

7. A device as claimed in any of claims 5 to 6, wherein the auger and/r the disc extend into the dispensing nozzle.

8. A device as claimed in claim 7, wherein during dispensing of the material, the disc and the auger are positioned at least partially within the receptacle into which the material is dispensed.

9. A dispensing device as claimed in any of claims 5 to 8, further comprising agitating means to agitate the material to be dispensed before being advanced by the auger.

10. A dispenser as claimed in any of claims 1 to 9, wherein the displacement means comprises a fluidoperated ram.

11. A dispenser as claimed in any of claims I to 10, wherein the dispenser further comprises conveyor means for conveying a succession of receptacles into which the material is to be dispensed.

12. A dispenser as claimed in claim 11, wherein the conveyor is movable stepwise to position each receptacle in turn beneath the nozzle.

13. A particular material dispenser comprising a plurality of dispensers as claimed in any of claims 1 to 12.

14. A dispenser as claimed in claim 13, comprising two dispensers arranged side-by-side and a conveyor beneath the dispensers adapted to advance two rows of receptacles towards the respective nozzles.

15. A particulate material dispensing device comprising a plurality of dispensing means, each dispensing means being provided with a single dispensing nozzle through which the material is dispensed.

16. A particulate material dispensing device comprising material dispensing means and a nozzle through which the material is dispensed, the nozzle being shaped such that the material dispensed therefrom assumes a convergant shape.

17. A device as claimed in claim 16, wherein the dispensed material converges to a neck and then diverges.

18. A device as claimed in any of claims 1 to 17, wherein each dispensing means comprises an auger housed within a cylindrical conduit.

19. A device as claimed in claim 18, further comprising a disc at the base of each auger, the disc being arranged to be rotatable with the auger.

20. A device as claimed in claim 18 or claim 19, wherein the auger and/or the disc extend into the dispensing nozzle.

21. A device as claimed in claim 20, wherein during dispensing of the material, the disc and the auger are positioned at least partially within the receptacle into which the material is dispensed.

22. A dispensing device as claimed in any of claims 18 to 21, further comprising agitating means to agitate the material to be dispensed before being advanced by the auger.

23. A particulate material dispensing device substantially as herein described, with reference to and as illustrated in, the accompanying drawings.