GB2081665A - Linear conveyor for confectionery products - Google Patents

Abstract

A linear conveyor for confectionery products, particularly filled and/or coated biscuits, is described which transports biscuits quickly and reliably without damaging them and without requiring the attendance of operators. This conveyor includes two lines of nozzles spaced apart in the direction of transport and arranged parallel to each other and to a conveyor belt (29) which extends between the said lines, e.g. in are rebate 31 in a wall 11 in which nozzles in the form of slits 16, 17 are provided, and carries the products to be transported, each with a central portion of its lower surface resting thereon, the said nozzles being directed substantially upwardly and supplying air under pressure towards portions of the lower surfaces of the products located laterally of the said central portions. <IMAGE>

Description

SPECIFICATION Linear conveyor for confectionery products The present invention relates to a linear conveyor for confectionery products, particularly for filled and/or coated biscuits.

Conveyors of the type specified are generally used for transporting biscuits from one machine to another, for example from a machine which coats the biscuits with chocolate to a machine which inserts the coated biscuits in suitable protective wrappings.

Now when the first machine provides an irregular output of biscuits and the second machine differs in that it has a step-wise operation, the conveyor which collects the biscuits also functions as a holding store, with a row of biscuits forming on one section thereof, lined up waiting to be received by the second machine.

It is essential for such conveyors to transport the biscuits quickly and reliably, without stoppages, without damaging them and without requiring the attendance of operators.

According to one known solution at present in use, conveyors of the type specified are constituted by a conveyor belt having a working pass which carries the biscuits to be transported.

Such conveyors have the disadvantage that they sometimes damage the biscuits lined up thereon and particularly those biscuits in the row which are closest to the machine for which they are destined. In fact, the belt advances at a speed greater than the row of biscuits and hence gives rise to a frictional force between the belt and each biscuit in the row. This force results in a contact force being exerted by each biscuit on the next biscuit in the row. Clearly such forces add up so that they easily reach values incompatible with the strength of the biscuits, particularly filled biscuits, which break up.

It has been proposed to use linear conveyors of the so-called idle-roller type, in which driven transport rollers have coaxial, idle cylindrical sleeves mounted thereon. Although theoretically such conveyors would result in a reduction in the frictional forces, they exert localised forces on the biscuits which the biscuits cannot stand up to; furthermore, such conveyors quickly lose their initial low-friction properties since fragments of biscuits or of the filling or coating thereof, readily aggregate thereon.

In another solution, use is made of conveyors on which the biscuits are forced to advance along a track by jets of air under pressure supplied by nozzles directed in the desired direction of transport. Although advantageous from certain points of view, such conveyors are difficult to realise in practice, particularly as regards the regulation of the air pressure. Indeed, high pressures, which are advantageous for ensuring transport of the biscuits, may cause some biscuits to fly off the track, while, on the other hand, low air pressures may be insufficient to prevent the biscuits sticking and jamming on the track. In addition, such conveyors have the disadvantage that every time the second machine receives a biscuit, and consequently the row of biscuits which is lined up has to advance by one step, there is difficulty in starting the row moving again.

The problem which is at the root of the present invention is that of devising a conveyor of the type specified which has structural and functional characteristics which can satisfy the said needs and, simultaneously, overcome the cited disadvantages of the known art.

The idea on which the present invention is based is that of using air under pressure to reduce the weight of the biscuits rather than to cause their advancement.

On the basis of this solution, and in order to resolve the said technical problem, the present invention provides a linear conveyor for confectionery products, particularly for filled and/or coated biscuits, which is characterised in that it includes, in combination: - at least one row of nozzles spaced apart in the direction of transport, - a conveyor belt extending longitudinally of the said at least one row and carrying the products to be transported, each with at least one portion of its lower surface resting thereon, -- the said nozzles being directed substantially upwardly and supplying air under pressure towards at least one portion of the lower surface of each product.

To advantage, there are two parallel :ows of nozzles and the conveyor belt extends between them so that the lower surface of each product has a central portion resting on the belt and portions on either side thereof subjected to the air under pressure.

Further characteristics and advantages of the conveyor according to the present invention will emerge from the following description of one preferred embodIment, given by way of nonlimiting example, with reference to the appended drawings, in which: - Figure 1 is a partially-sectioned, schematic, elevational view of a linear conveyor according to the invention; - Figure 2 is a perspective view of a detail of the conveyor of Figure 1; and - Figure 3 is a sectional view of the conveyor of Figure 1 taken on line Ill-Ill of Figure 1.

The linear conveyor according to the invention, illustrated in the drawings and indicated in its entirety by 1, is interposed between a machine 2 and a machine 3, of conventional types, which carry out the respective operations of coating confectionery products, such as biscuits, with chocolate and inserting them in suitable protective wrappings.

The conveyor 1 transports the biscuits, each indicated by 4, from the machine 2 to the machine 3.

The biscuits 4 are circular, are filled with a layer 5 of cream placed between the two layers 6 and 7 of biscuit and are coated with a thin layer 8 of chocolate. These biscuits are especially crumbly, a characteristic which-makes them particularly appreciated when eaten but which, on the other hand, makes them difficult to handle during manufacture.

The linear conveyor 1 includes a support structure 9, which bears on the ground through suitable supports 9a.

The structure 9 carries a tubular duct 10 of substantially rectangular cross-section which extends in the direction of transport. A wall 11 of the duct 10 is horizontal and has a width 1 slightly greater than the diameter d to the biscuits 4.

Walls 12 and 13 of the duct 10, adjacent the wall 11, are extended upwardly to respective side walls 14 and 15. The wall 11 and the side walls 14 and 1 5 define a guideway 1 a for the biscuits 4 during their transport.

Along the wall 11 are formed two parallel rows 1 6 and 17 of slits, each referenced 1 8. The slits 18 are rectangular, of predetermined length "a" and inclined at a predetermined angle a to the direction of transport so that, with reference to this direction, where one slit ends the next begins.

The slits 18 are, to advantage, formed by folding precut sections 19 of the wall 11 inwardly of the duct 10.

The duct 10 is closed at its ends by end walls 20 and 21 and is provided with inlets 22 and 23 connected to supply tubes 24 and 25 for compressed air; the compressed air is generated by a compressor 26, of conventional type, mounted on the structure 9. The size of the intake opening 27 of the compressor 26 can be varied by varying the angular position of a movable sector (28) to regulate the air pressure, as needed.

The said slits 18, as a result of the air pressure which establishes itself within the duct 10, constitute as many nozzles, directed substantially upwardly, which suppiy air under pressure upwardly and hence towards the biscuits 4 which are in the guideway 1 a.

The linear conveyor 1 further includes a conveyor belt 29 which extends longitudinally of the rows 16 and 1 7 and between them; the working pass 29a of the belt 29 carries the products 4 which are in the guide path 1 a and which rest upon it.

The conveyor belt 29 is of the endless-belt type, passing around end pulleys each indicated by 30 and at least one of which is driven. A rebate 31 is formed in the wall 11 to house the working pass 29a of the belt 29; the rebate has a depth slightly less than the thickness of the belt 29.

A central portion of the lower surface of each of the biscuits 4 in the guideway 1 a thus rests on the working pass 29a of the belt 29, the portions on either side of this central portion being subjected to air under pressure.

The air pressure is chosen in dependence on the weight of each biscuit and, more particularly, such that a fixed proportion of the weight of the biscuit, for example 70%, will be sustained by the air pressure while the remaining proportion, 30%, of the weight ensures that the biscuit rests on the conveyor belt, and hence ensures the desired transport of the biscuit.

The conveyor according to the invention is further provided with a removable guide member 32 which extends over the working pass 29a at a predetermined distance therefrom greater than the thickness (s) of the biscuits 4. The guide member 32 is constituted by a succession of rods 33, having their ends side by side, supported by arms 34 rotatably mounted on pins 35 for the removal of the said guide members.

The guide member 32 holds the biscuits 4 within the guideway 1 a during the phase in which the conveyor is put into operation and particularly during regulation of the pressure. When the pressure has been regulated to its correct value,in accordance with the criteria mentioned above, and the biscuit conveyor can be started, the biscuits rest safely on the belt and hence the stop member is inoperative and may even be removed.

During transport, and according to the output of biscuits by the machine 2 and the working rhythm of the machine 3 in general, a certain number of biscuits 4 waiting to be received by the machine 3 line up in a row occupying a terminal section of the conveyor of length L, while other biscuits 4 which are scattered, as released by the machine 2, occupy the remaining section of the conveyor 1.

The conveyor 1 according to the invention is further provided with photoelectric-cell type transducers 36, 37 and 38 of conventional type, disposed along the guideway 1 a, at the output end, the input end and in a predetermined intermediate position, respectively.

The said transducers are arranged to signal the presence of biscuits 4 in the line and the signals given thereby are used to control the operative cycle of the machines 2 and 3. More particularly, the signal given by the transducer 38 is used to increase the rate of working of the machine 3; the signal from the transducer 36 is used to stop the machine 3; finally the signal from the transducer 37 is used to slow, stop or otherwise change the output of the machine 2.

On the basis of the above description, the conveyor according to the invention has the following advantages.

First of all it allows the biscuits to be transported safely, without damaging them.

Indeed the frictional force which is exerted between the belt and the biscuits which are in lin'e is reduced in practice to a very small percentage of the values typical for conveyors of the known art thanks to the support given to the biscuits by the air.

A further advantage of the conveyor according to the invention lies in the fact that the biscuits rest steadily on the conveyor belt during transport without flying off as is typical of the air conveyors of the known art, described above. Indeed the air pressure in the conveyor according to the invention can safely and easily be regulated according to the individual conditions needed to keep a biscuit resting on the belt, even though the contact pressure is limited.

A further advantage of the conveyor according to the invention lies on the fact that it functions uninterruptedly for long periods of time without requiring the attendance of operators. Indeed in the conveyor according to the invention, the biscuits release negligible quantities of crumbs and the like. Even these few fragments could accumulate and cause sticking and jamming, but are easily removed by the air pressure as they are formed.

Claims (3)

1. Linear conveyor for confectionery products, particularly filled and/or coated biscuits, characterised in that it comprises, in combination: - at least one row of nozzles spaced apart in the direction of transport, - a conveyor belt extending along the said at least one row and carrying the products to be transported with at least one portion of their lower surfaces resting thereon, -the said nozzles being directed substantially upwardly and supplying air under pressure towards at least one portion of the lower surfaces of the said products.

2. Linear conveyor according to Claim 1, characterised in that there are two parallel rows of nozzles and the conveyor belt extends between them, so that the lower surfaces of the products have a central portion resting on the belt and portions laterally thereof subjected to the air under pressure.

3. Linear conveyor according to the preceding claims and as described and illustrated for the purposes specified.