GB2120516A - Manufacture of articles such as sandwich biscuits - Google Patents

Abstract

An article comprising a base component (45) having on it a layer (46,52) of an extrudable material and optionally an upper component (49) disposed upon the layer of material, such as cream-coated biscuits or cream-filled sandwich biscuits, is made by moving a supply nozzle (12) producing the layer (46,52) of extrudable material relative to a continuous and mutually abutting sequence of the base components (45) and, if desired, then applying another sequence of the upper components (49) on to the layer (46, 52), with each upper component (49) and in register with a base component (45). The resultant train (50,51) of coated components or filled double components is separated into the desired articles by effecting relative movement of the leading article (50) and the next-following article (51) so as to break the layer (52) between them, preferably by tilting each leading article about a transverse roller (53) while restraining (55) the next-following one. <IMAGE>

Description

SPECIFICATION Manufacture of articles such as sandwich biscuits This invention relates to the manufacture of articles such as sandwich biscuits and is concerned, in particular, with the well-known sandwich kind, which consist of two biscuits united by an intermediate filling, usually called a "cream". The invention also has application to the manufacture of other articles, such as creamtopped biscuits, which comprise a biscuit or like base component supporting an upper component such as a so-called cream, which like the filling in sandwich biscuits is capable of application by extrusion on to the upper surface of a base component. Similarly, the invention can find application in the manufacture of articles generally, such as cream-topped or iced cakes, which comprise an upper extrudable component and a base component, such as a portion of a cooked cake mix.All of the articles to which the invention can relate have in common the problems involved in applying the extrudable cream or other upper component to the appropriate part or region of the top surface of the base component, together with the additional problem of registration in the particular case, where the benefit of the invention can especially be realised, in which an upper component is applied and the article must maintain a high degree of registration or spatial relationship between the upper and base components having the filling between them.

Because of the additional problems involved in the manufacture of articles of sandwich construction, the following description will refer to such articles in large measure, though as already indicated the invention is broader in concept and is not to be regarded as limited to such articles, Many kinds of partly or wholly coated or enrobed biscuits are also made and it is very common for the enrobing composition to be beased upon chocolate or similar materials.

Cream-filled sandwiches are usually made by inverting half the supply of biscuits coming from the oven, so that their moulded faces are downwards, depositing discrete quantities of the cream upon the non-moulded upper faces of these lower biscuits and then applying the other biscuits with their non-moulded lower faces over the cream deposits. The amounts of cream applied and other variable factors, such as the temperature, viscosity and other properties of the cream, have to be very carefuily controlled so that satisfactory adhesion of the biscuits and the desired degree of filling are obtained.Deposition of the cream usually takes place either by a stencil technique, in which the lower biscuits are brought from below into register with holes in a stencil sheet and the cream is applied to the biscuits in the apertures in the stencil sheet, or by means of a rotating hollow drum provided with apertures of the desired shape in its surface, the cream being forced out through the apertures and then being cut from the surface of the drum by a wire, so that each portion -of the cream is applied to the upturned face of a biscuit.

In order to minimize problems during manufacture and also in packaging, it is conventional practice to arrange for the cream filling not to extend completely to the edges of the sandwiches. This reduces spillage of cream on the machinery and also prevents contact between the cream and the packaging material subsequently put round the sandwiches.

Where sandwiches are being manufactured which are also enrobed, it is unnecessary for the biscuits to have one face moulded and it is thus unnecessary to invert half the supply, as the biscuits can simply be divided into lower and upper streams without any being inverted.

Nevertheless, considerable problems can arise, particularly because in the conventional way the cream filling is not fully coextensive with the opposed biscuits. For example, chocolate and most other enrobing materials are more expensive than cream fillings and the proportion of the total amount of enrobing material used which fills the slot around the edge of each sandwich can represent as much as 20% of the total chocolate or other yen robing composition. Coated sandwiches of identical appearance could be made less expensively, if the uncoated sandwiches were filled to the edges.Also, chocolate and most other enrobing materials are applied hot and one of the most difficult problems in coating sandwiches is the umbrella effect caused as the chocolate or other composition flows from the edges of the upper biscuits, as it tends not to flow into the edge slot but to fall down to the corresponding edges of the lower biscuits, trapping air between itself and the edge of the cream. The heat of the enrobing composition then causes this air to expand and blow holes through the chocolate coating where it extends across the gap. Not only are the resuiting biscuits of unsatisfactory appearance, due to the apertures at the edges where the chocolate coating should be complete, but also these apertures allow moisture to penetrate, softening the biscuits and leading to the production of coated sandwiches which are not of the desired quality.

This invention is therefore concerned with the particular problems which can arise in the manufacture of coated sandwiches, but is also directed generally to the difficult problem of making topped or iced cakes and other articles having an extrudable upper component and also of making filled articles comprising a cream centre between biscuits in the form of sandwiches, whether or not they are subsequently coated or enrobed, so that the cream filling extends over precisely the desired part and can, if desired, fill the biscuits substantially to their edges. The invention thus enables sandwiches to be made having a filling which is substantially co-extensive with the opposed biscuits, but without meeting the difficulties of known methods and also so that more completely filled and therefore more attractive and saleable products are formed.The invention also produces sandwiches which can be more easily and satisfactorily subjected to partial or complete enrobing than sandwiches made by the conventional methods of manufacture.

Although cream-filled sandwiches of every conceivable shape are known and this also applies to biscuits which are coated or enrobed, the invention is essentially concerned with sandwiches which are rectangular and are thus made from two like rectangular biscuits having a ribbon-shaped layer of cream filling between them.

According to the present invention, a plurality of articles each comprising a base component and a superposed layer of extrudable material are produced by: (a) arranging a plurality of the base components as a continuous sequence having the ends of adjacent components in abutting relationship, (b) effecting relative movement between the sequence of abutting base components and a supply nozzle arranged to deposit a continuous layer of the material on the upper surfaces of the base components, the layer of material having a width not more than the width of the base components, and (c) effecting relative movement of the abutting ends of consecutive base components so as to separate the layer between them.

Preferably, the supply nozzle is stationary and the sequence of abutting base components moves past it in the direction of supply of the filling material.

According to an especially preferred embodiment of the invention, a sequence of upper components of the articles is applied to the upper surface of the layer of material so that each upper component registers with a base component, prior to effecting the relative movement of step (c).

In a preferred embodiment of the invention, the relative movement of the abutting ends in step (c) is effected in a direction perpendicular to the plane of the base components and their superposed layers of material, while this relative movement is most advantageously effected by tilting a base component about an axis extending transversely of the layer of material.

Where an upper component is employed and is applied to the extruded layer, separation is advantageously accomplished by applying a downwardly-directed force on the leading upper component at a position downstream of the transverse axis, relative to the direction of movement, whereby the leading article is separated from the next-following article.

Preferably, the next-following article is restrained against upward movement during application of the downwardly-directed force to the leading upper component. Where used, therefore, as in the manufacture of sandwiches, the sequence of upper biscuits is preferably also continuous and is advanced so as to approach the filling layer in register with the sequence of lower biscuits. The sequence of lower biscuits is preferably moved along a substantially horizontal path which passes under the outlet of the supply nozzle. The biscuits are rectangular, as already indicated. The process of the invention can thus apply to the manufacture of square sandwiches, but in practice most sandwiches have a long dimension and a short dimension.The invention can be practised with the biscuits advancing either along or transversely of their longer dimension, but the invention is of particular utility when the biscuits are fed in a continuous sequence, that is to say with each biscuit touching the next, which moves in the direction of the longer dimension of the biscuits.

The layer of filling material can be deposited so as to have a width less than that of the width dimension of the sequence of biscuits, but in a particular embodiment of the invention, the filling material is deposited so that the layer has substantially the same width as the biscuits, so that the long sides of the layer of filling material extend along the long sides of the lower biscuits and, since the upper biscuits register with them, also along the long sides of the upper biscuits.

Sandwiches made by this embodiment of the invention are especially suited to be coated or enrobed, as the problems mentioned above are unlikely to occur.

The result of the first two steps incorporated in this particular preferred embodiment of the process of the invention is thus to produce a continuous sequence of sandwiches, each comprising an opposed pair of biscuits and the whole sequence being united by a continuous ribbon or layer of filling material. The next step in the process is to separate the filling material between the sandwiches so as to produce the desired products, which may then be packaged or, if desired, may then be subjected to further manufacturing steps, such as chocolate enrobing.

This next step is based upon the discovery that the layer of filling material can be satisfactorily severed along the line between consecutive sandwiches by relative movement of the adjacent ends of the sandwiches. Each entire sandwich can be displaced forwardly, downwardly, upwardly or laterally to separate it from the next. Preferably, however, the relative movement causing separation is effected in a direction generally normal to the plane of the layer of filling material.

It is found that the layer separates very cleanly because of the scissor-like action which the lower biscuit of one sandwich makes in conjunction with the upper biscuit of the other sandwich.

Preferably, this relative movement is effected by tilting each sandwich about a horizontal transverse axis, while the preceding sandwich is continuing its advance movement, e.g.

immediately or shortly after the upper biscuit has been placed on the filling material on the lower biscuit. Downward tilting of the forward end of each sandwich is preferable, as this raises the rearward end sharply and makes the desired separation of the cream layer. Immediately before the tilting station, each sandwich can pass some form of restraint, such as a roller running on the upper surface, which maintains the sandwiches in their forward travel while the one at the head of the line has gone past the restraint and is undergoing the tilting operation which effects the relative movement to separate the cream layer along the line between the consecutive sandwiches. This restraint stops the succeeding sandwich from moving upwardly with the rear end of the tilted sandwich.

In order that the process of the invention may be fully understood and appreciated, a preferred form of it and the associated apparatus are described below, by way of example only, in conjunction with the accompanying drawings; various modifications of the various steps in the process and of the various units of apparatus are also described.In the drawings: Fig. 1 shows the main components of apparatus for the manufacture of sandwiches according to the process of the invention, in block diagram form, with some possible variants, to assist in explaining the main steps in the process; Fig. 2 shows very diagrammatically in side view at the top and in plan view below the sequence of steps in the process of the invention; Fig. 3 is a block diagram of the control system arrangement required for apparatus to enable the process of the invention to be carried out; Fig. 4 shows in diagrammatic side view the step of extrusion of the cream on to the lower biscuits; Fig. 5 shows, also in diagrammatic side view like Fig. 4, the step of sandwiching of the top biscuits on the cream on the bottom biscuits;; Figs. 6(a) to 6(f) show in a similar manner to Fig. 5 a number of possibilities of registration error in the sandwiching step, which have to be avoided or corrected by the apparatus in carrying out the process of the invention; Fig. 7 shows, also in diagrammatic side view like Figs. 4 and 5, the step of separation of the cream layer.

Referring to Fig. 1, the block diagram shows the arrangement of the main apparatus components required for the manufacture of enrobed sandwich biscuits, in accordance with the process of the invention. Essentially, the invention comprises operation of the apparatus units contained within the chain-dotted line 10. This apparatus comprises a bottom conveyor 11 which supplies a continuous sequence of rectangular biscuits, i.e.

the biscuits are in head-to-tail contact, to an extruder 12 where a continuous cream layer is applied to the biscuits on the conveyor 11. The continuous sequence of creamed biscuits then pass from the extruder 12, which operates in the direction of advance, to a sandwicher 13 where a second continuous sequence of biscuits of the same shape are supplied by a top conveyor 14 and are brought into registration with those on the bottom conveyor 11. The resultant sequence of sandwiches then passes through a separator 15, where the cream layer is divided between the consecutive sandwich units in the way already described.The apparatus units 11 to 1 5 in practice will usually form part of a more extensive arrangement of apparatus units, starting with a conventional rotary moulder 1 6 where the biscuit dough is shaped and deposited upon the band of an oven 1 7. The cooked biscuits emerging from the oven 1 7 will typically be divided into separate streams passing respectively to the bottom conveyor 11 and the top conveyor 14, for instance by a divider unit represented at 1 8. This may incorporate a lane reducer in conventional manner, for instance if a large number of rows of biscuits are delivered from the oven 17, for instance 1 8 or 24 rows of biscuits, which number needs to be reduced to a lesser number in order to enable the various later steps in the overall process to be carried out at the appropriate rate.

Thus, some form of divider/reducer 1 8 will usually be provided between the oven 17 and the bottom and top conveyors 11 and 14.

An alternative arrangement may involve the use of a bottom magazine 19, which receives part of the supply of biscuits from the divider/reducer 18, and a top magazine 20, which receives the other part. The magazine 19 and 20 may constitute the first units of the apparatus carrying out the process, for instance, if production of the biscuits takes place in a different location from where the sandwiching and later steps are carried out. If provided, the bottom magazine 1 9 constitutes the supply of biscuits to the bottom conveyor 11 and the top magazine 20 constitutes either the supply of biscuits to the top conveyor 14 or a supply direct to the sandwicher 1 3.

Depending upon the particular apparatus arrangements used, the biscuit sandwiches leaving the separator 1 5 may pass to a further unit which divides the rows of sandwiches into a smaller number of rows or which effects lane multiplication to give a larger number of rows, so that a unit indicated generally as a divider/multiplier 21 may follow the separator 1 5.

In the manufacture of coated sandwiches, the next apparatus unit is an enrober 22 operating according to conventional technique, following which the coated sandwiches are forwarded to the final stage for packaging, indicated at 23. Thus, the process according to the invention can be carried out in apparatus of the kind diagrammatically indicated in Fig. 1 and essentially includes effecting relative movement of the continuous sequence of lower biscuits and the supply nozzle, this sequence being on the bottom conveyor 11 and passing the nozzle of the extruder 12, which deposits an uninterrupted layer of filling material on the lower biscuits so that the layer has a width which is the same as or less than the width of the sequence of biscuits. The upper sequence of biscuits advancing on the top conveyor 14 are then brought into register with the lower sequence in the sandwicher unit 13, following which the separator 1 5 causes the consecutive sandwiches in the sequence to undergo relative movement of their adjacent ends, so that the filling layer is separated between each sandwich unit and the next.

Fig. 2 indicates diagrammatically the paths followed by the lower biscuits, the top biscuits and the resultant sandwiches, in side view in the upper part of the figure and in plan view in the lower part. For simplicity, the various parts shown in Fig. 2 are indicated with the references used in Fig. 1, except that each reference is increased by 100.Thus, a lower sequence 111 of biscuits passes in a generally horizontal straight line past the nozzle of a cream extruder 112, whilst an upper sequence 114 of biscuits is brought over the extruder 112 and into line with the lower sequence 111, sandwiching of the upper and lower biscuits taking place at 11 3. The continuous sequence of sandwiches so produced then proceeds to the separation stage 11 5 where, as indicated at the left of the side view, the sandwiches are typically downwardly inclined in order to effect separation of the filling layer between the consecutive sandwich units.

The control mechanism required in practice for a typical apparatus constructed to carry out the process of the invention is shown in Fig. 3 in block diagram form. Again, the same references are used as in Fig. 1 where appropriate, namely a bottom conveyor 11 for lower biscuit transport and a top conveyor 14 for upper biscuit transport, the extruder outlet being indicated at 12.

The apparatus also includes a main drive 25 having a first output 26 operating the lower biscuit conveyor 11, a second output 27 connected to a unit A, to be described in more detail below, having its output 28 connected to a pump and nozzle unit 29 feeding the extruder 12, and a third output 30 connected to a differential 31, the output 32 of which operates the upper biscuit conveyor 14. Control of the lower and upper sequences of biscuits is provided by advancing the lower biscuit conveyor 11 at a steady rate by means of the main drive output 26 and advancing the upper biscuit conveyor 14 at an adjustable rate by means of the main drive output 30 and a control operation provided by the differential 31.The differential output 32 allows the main drive 25 to operate the upper biscuit conveyor 14 at the same rate, at a slower rate or at a higher rate than the lower biscuit conveyor 11 as is required to maintain exact registration between the respective lower and upper sequences of biscuits. Precise registration is essentially obtained by sensors 33 which receive an input 34 from the lower biscuit conveyor 11 and an input 35 from the upper biscuit conveyor 14 and transmit the resultant information via an output 36 to an electronic or other control unit 37.

This has a connection 38 to a control unit C, described in more detail below, which in turn is operatively connected by its output 39 to the main drive 25. The control unit 37 also has a connection 40 to a control unit B, described in more detail below, which in turn is operatively connected by its output 41 to a correction motor 42. This is connected via its output 43 to the differential 31.

The units A, B and C constitute three control loops in the arrangement and interaction of the main apparatus components shown in Fig. 3. The unit A can conveniently constitute a variable ratio coupling located between the main drive 25 and the pump and nozzle unit 29, which matches operation of the latter to the speed of the lower biscuit conveyor 11, so that the cream layer deposited on the lower biscuits has the desired width and thickness.

The variable ratio unit A can be controlled either by the machine operator or by a closed loop arrangement with additional sensors providing feedback. Simple manual setting of the drive ratio is found to be generally satisfactory. Assuming that the pump and nozzle unit 29 is arranged to operate satisfactorily, the linear speed of the extruded cream layer can be accurately fixed relative to the linear speed of the biscuits on the lower biscuit conveyor 11.

The unit B essentially serves to control registration of the lower and upper biscuits by effecting any necessary correction of the relative speeds of the conveyors on which the sequences of biscuits are travelling. One embodiment of this feature of the apparatus of the invention is the provision of a toothed wheel, mounted on one of the main drive 25 outputs and arranged to generate a number of pulses proportional to the distance moved. The number of pulses which may occur between two successive signals generated by the sensors 33 can thus be made to represent the registration error. Registration control effected in this general way can be provided by one of a number of indexing methods, which serve in general to convert the error count sensed into a rotational input to the differential 31.Thus in one embodiment of the invention, the unit B feeds a stepper motor serving as the correction motor 42.

Stepper motors have a number of advantages including the following: Discrete step movement can be matched to the error count, for instance so that one step of the motor 42 is equivalent to one pulse of the toothed wheel; There is sufficient holding torque when the correction motor 42 is stationary, so that the differential satisfactorily transmits the uncorrected output from the main drive 25 to the upper biscuit conveyor 14; The low speed torque available allows direct drive with low inertia; These motors are of simple construction and have high reliability.

Thus the sensing of lack of registration, if a top biscuit is either ahead or behind the corresponding bottom biscuit, causes the electronic unit 37 and the unit B to actuate the correction motor 42 in the appropriate sense, so that is causes the differential 31 to reduce or increase the output from the main drive 25 correspondingly, the upper biscuit conveyor 14 correspondingly retarding or accelerating the supply until the respective lower and upper biscuit sequences are in register again.

Unit C if used enables speed control of the extruder 1 2 either in relation to the linear speed of the lower biscuit conveyor 11 or in relation to another parameter, such as a given cream supply rate or a given lower biscuit supply rate.

Referring to Fig. 4, the process and apparatus of the invention apply to manufacture of sandwich biscuits which are rectangular, including square biscuits. In the usual case where the sandwiches are made from biscuits having one dimension larger than the other, two possibilities are given for forming the sequences of biscuits on the bottom and top conveyors 11 and 14. In one possibility, the biscuits advance in a continuous sequence with their longer edges in contact, so that the individual biscuits move in a direction transversely of their longer dimension and, in the other, the biscuits advance with their shorter edges in contact, so that they move in the direction of their longer dimension. In either case, it is possible to apply the cream at the extruder 12 as a ribbon which is either less than or equal in width to the width of the biscuits in the sequence.

In general, it is preferable for the biscuits to travel in a head-to-tail continuous sequence in the direction of their longer dimension and to deposit a continuous ribbon or layer 46 of cream from the extruder 12 either with the same width as the shorter dimension of the biscuits or with a width somewhat less than this. The nozzle of the extruder 12 thus defines the thickness and the width of the cream, which are the two smaller of the dimensions of the cream in the eventual sandwich and are ther.efore less variable and easier to control. Nevertheless as indicated in Fig. 4, it is necessary to maintain accurate control of the operation of the extruder 12, so as to ensure that the layer 46 of cream continuously deposited on the lower sequence of biscuits, indicated at 45, maintains the desired uniformity of depth and width.Correct matching of the speed of the lower sequence of biscuits 45 and the rate of extrusion of the cream layer from the extruder 1 2 is diagrammatically indicated at 46 in Fig. 4, together with the two possible faults. The cream path represented by the layer loop 47 shown in broken lines arises if the cream is extruded at too high a rate, whilst the cream path represented by the layer loop 48 shown in chain-dotted lines arises if the cream layer is extruded at too slow a rate. Various disadvantages can arise if the optimum cream path 46 is not obtained, including interruption or unevenness of the cross-section of the cream layer 46 and possible misalignment of the biscuits 45.In practice, the extruder 12 is supplied by a unit comprising a pump and nozzle such as that shown at 29 in Fig. 3, under the control mentioned above, so that metering of the cream is effected by the pump and the other variables are maintained in the appropriately controlled manner so that the cream is fed to the pump at a constant temperature and constant pressure.

The next stage in the process of the invention, in which the upper sequence of biscuits are brought into registration with the creamed lower sequence, is shown diagrammatically in Fig. 5.

The bottom conveyor 11 is shown with the sequence of lower biscuits 45 and above them the continuous layer 46 of cream. The upper sequence of biscuits are indicated at 49, where they are shown leaving the forward end of the upper biscuit conveyor or transport 14, shown diagrammatically as a guide plate.It has been found desirable for the upper biscuits 49 to approach the cream layer 46 on the lower biscuits 45 at a small angle, which can be in the range from 30 to 80 and is most preferably 5 . Each upper biscuit 49 thus deposits its forward end first on the cream layer 46, the contact lines between the upper biscuits 49 being in register with the contact lines between the lower biscuits 45, and continued advance of the lower biscuit transport or conveyor 11 allows each upper biscuit 49 to leave the top biscuit conveyor 14 and fall on to the cream layer 46, so as to produce the desired continuous sequence of sandwich biscuit units.

The various views of Fig. 6 represented by Figs.

6(a) to Figs. 6(f) inclusive show various forms of registration error which can arise and which need to be corrected in operation of the apparatus. In practice, most registration errors are caused by breakage of one of the lower or upper biscuits 45 or 49, as their production in the rotary moulder 16 and oven 1 7 or other supply apparatus, mentioned above in connection with Fig. 1, will normally ensure that the baked biscuits are uniform in dimensions. Referring to Fig. 6(a), therefore, if a lower biscuit 45 is too long, for instance by reason of the corresponding upper biscuit 49 being broken and therefore too short, it is necessary to retard progress of the succeeding upper biscuits 49 until proper registration is restored.Referring to Fig. 6(b), if the converse is found and the upper biscuit 49 is too long, for instance because the corresponding lower biscuit 45 is broken and so too short, the appropriate correction is to advance the succeeding upper biscuit 49. In practice, this cannot be done before any incorrectly-formed sandwich has been removed, as otherwise continued advance of the succeeding upper biscuits 49 would lead to an overlap, such as illustrated in Fig. 6(e). Also, if advance of the top biscuits is effected after the front edge of an adjusted upper biscuit 49 has fallen behind the rear edge of the one ahead of it, this will also advance the sandwiches already completed. This will probably neck the cream between these units, as illustrated in Fig. 6(f). The remaining possibilities are where the upper biscuit 49 is too long for reasons other than breakage of the corresponding lower biscuit 45, as illustrated in Fig. 6(c), and where the top biscuit 49 is too short in comparison with the corresponding lower biscuit 45, other than through breakage of the top biscuit 49, as illustrated in Fig. 6(d). In practice, there possibilities are less likely. Also, it can be seen that the error indicated in Fig. 6(c) is effectively the same as that illustrated in Fig. 6(b) and the error indicated in Fig. 6(d) is effectively the same as that indicated in Fig. 6(a) and corresponding correction will deal with the situation.

The next stage in the process carried out in the apparatus, following registration in the sandwicher 13 as just described, is separation of the sandwich units from one another. This can be effected by an apparatus such as that illustrated in Fig. 7. This shows the forward end of the bottom conveyor 11 and the rearward part of a completed sandwich 50 which has been separated from the succeeding sandwich, the forward part of which is illustrated at 51. Each of the sandwiches 50 and 51 consists of a lower biscuit 45, an upper biscuit 49 and the intermediate cream layer, indicated at 52. In order to effect relative movement of the sandwiches 50 and 51 so as to divide the cream along the contact iine, it has been found particularly suitable, especially with rectangular sandwiches fed in the direction of their longer dimension, to effect tilting of the forward sandwich 50.A smali pivoting roller 53 is mounted in the apparatus on the forward projection of the lower biscuit conveyor 11 , where the latter terminates its forward run and passes downwardly around a front roller, only partly shown in Fig. 7. The conveyor 11 causes each sandwich to continue its advance in the same direction on to the pivoting roller 53. Beyond this, the transport means for the sandwich allow it to tip or tilt downwardly, as indicated at the left end of the side view of Fig. 2 and at 54 in Fig. 7. On reaching this position, the forward sandwich 50 overbalances at the pivoting roller 53, which has its axis transversely of the direction of movement of the sandwiches. It is found desirable to provide a resilient roller 55 or other restraint for the sandwiches.This roller 55 runs on the upper surfaces of the sequence of sandwiches, so that each following sandwich 51 is maintained in contact with the conveyor 11 and is prevented from participating in the upward movement of the rear end of the forward sandwich 50. Thus the cream layer 52 is separated by what amounts to a scissor-like action between the rear end 56 of the lower biscuit 45 of the forward sandwich 50 and the front end 57 of the upper biscuit 49 of the rearward sandwich 51. Tilting can be effected by a roller, a weighted arm or other pressure applicator 58 positioned so as to cause downward movement of the front end of each sandwich as its middle passes over the roller 53.

The sandwiches are thus formed and the cream is cleanly severed at their rearward and forward edges so as to complete production of the desired sandwiches ready for them to pass to later stages in the overall process, which as previously indicated can include enrobing if desired and also can include packaging. If non-coated sandwiches are to be made, the exceptionally high degree of control afforded by the process and apparatus of the invention enables the filling to be provided, in accordance with convention, so that it does not extend to the edges of the sandwich parallel to the direction of feed of the biscuits. Problems due to contact of the filling at these edges, with packaging material for instance, do not arise.

Other arrangements can be provided to prevent contact of the cream filling with the packaging material, for instance at the transverse edges, and it is also possible with the process and apparatus of the invention to ensure that the cream filling is completely co-extensive with the biscuits forming the sandwiches. This would also be the preferred technique when making coated sandwich biscuits, when the aforementioned problems of umbrellaring and the related difficulties of conventional methods will not arise.

As indicated, the particular form of the invention described above in relation to the drawings represents an especially preferred embodiment of the process, the success of which is due in particular to the high degree of control over the feeding of the sequences of biscuits and the extrusion of the cream filling which the electrical circuitry makes possible. The invention also includes a less complex form of manufacture of coated articles, as already mentioned, which in essence comprises the sandwich-making method already described in detail, minus the provision of a sequence of upper components and therefore the control means necessary for them when used.

In either embodiment of the method, the abutting ends of adjacent components are their shorter edges. The layer of the material may have a width less than the width of the components of the articles or it may have a width equal to that of the components of the articles.

An apparatus according to this invention comprises means for supporting a plurality of the base components as a continuous sequence having the ends of adjacent components in abutting relationship, an extrusion nozzle arranged to provide a continuous layer of the extrudable material, means for effecting relative movement between the nozzle and the sequence of base components so that the continuous layer of material is deposited upon the sequence of base components and separation means for effecting relative movement of the abutting ends of consecutive base components so as to separate the layer of material between them. The apparatus preferably includes means between the nozzle and the separation means for supplying a sequence of upper components of the articles to the upper surface of the layer of material, each upper component being supplied in registration with a respective base component.

In a preferred embodiment of the apparatus, sensors for detecting mis-registration of the upper and base components are provided and control means responsive to the sensors serve for adjusting the speed of relative movement between the nozzle and the sequence of base components and/or the rate of supply of the sequence of upper components, whereby registration between the components is re-established.

The various aspects of the invention make a contribution of considerable significance to the manufacture of coated and filled articles such as creamed cakes and sandwich biscuits.

Claims (28)

1. A method of producing a plurality of articles each comprising a base component and a superposed layer of extrudable material, which comprises: (a) arranging a plurality of the base components as a continuous sequence having the ends of adjacent components in abutting relationship, (b) effecting relative movement between the sequence of abutting base components and a supply nozzle arranged to deposit a continuous layer of the material on the upper surfaces of the base components, the layer of material having a width not more than the width of the base components, and (c) effecting relative movement of the abutting ends of consecutive base components so as to separate the layer between them.

2. A method according to claim 1, in which the supply nozzle is stationary and the sequence of abutting base components moves past it in the direction of supply of the material.

3. A method according to claim 1 or 2, in which the relative movement of the abutting ends in step (c) is effected in a direction perpendicular to the plane of the base components and their superposed layers of material.

4. A method according to claim 3, in which the relative movement of step (c) is effected by tilting a base component about an axis extending transversely of the layer of material.

5. A method according to any preceding claim, in which the base components have the form of rectangular plates.

6. A method according to any preceding claim, in which a sequence of upper components of the articles is applied to the upper surface of the layer of material so that each upper component registers with a base component, prior to effecting the relative movement of step (c).

7. A method according to claims 5 and 6, in which the tilting is effected by applying a downwardly-directed force on the leading upper component at a position downstream of the transverse axis, relative to the direction of movement, whereby the leading article is separated from the next-following article.

8. A method according to claim 7, in which the next-following article is restrained against upward movement during application of the downwardlydirected force to the leading upper component.

9. A method according to any of claims 5 to 8, in which the upper and base components each have the form of rectangular plates.

10. A method according to claim 5 or 9, in which the abutting ends of adjacent components are their shorter edges.

11. A method according to any preceding claim, in which the layer of the material has a width less than the width of the components of the articles.

12. A method according to any of claims 1 to 10, in which the layer of the material has a width equal to that of the components of the articles.

13. A method according to any of claims 6 to 12, in which the base and upper components are biscuits and the articles are sandwich biscuits.

14. A method according to claim 13, in which the sandwich biscuits are enrobed in a coating material after being separated in step (c).

1 5. A method of making articles according to claim 1, substantially as hereinbefore described with reference to the accompanying drawings.

1 6. An article comprising a base component and a superposed layer of material, when made by a method according to any of the preceding claims.

1 7. A sandwich biscuit, when made by a method according to any of claims 1 to 1 5.

18. An apparatus for producing a plurality of articles each having a layer of extrudable material, disposed upon a base component, comprising means for supporting a plurality of the base components as a continuous sequence having the ends of adjacent components in abutting relationship, an extrusion nozzle arranged to provide a continuous layer of the extrudable material, means for effecting relative movement between the nozzle and the sequence of base components so that the continuous layer of material is deposited upon the sequence of base components and separation means for effecting relative movement of the abutting ends of consecutive base components so as to separate the layer of material between them.

19. An apparatus according to claim 1 8, including means between the nozzle and the separation means for supplying a sequence of upper components of the articles to the upper surface of the layer of material, each upper component being supplied in registration with a respective base compqnent.

20. An apparatus according to claim 19, wherein sensors for detecting mis-registration of the upper and base components are provided and control means responsive to the sensors serve for adjusting the speed of relative movement between the nozzle and the sequence of base components and/or the rate of supply of the sequence of upper components, whereby registration between the components is re-established.

21. An apparatus according to claim 1 9 or 20, in which the means for supplying the upper components comprise a conveyor.

22. An apparatus according to any of claims 1 8 to 21, in which the nozzle is stationary and the means for effecting relative movement comprise a conveyor.

23. An apparatus according to any of claims 18 to 22, in which the separation means are operable to break the layer of material between the respective leading article and the next-fbllowing article and comprise a roller extending transversely of the means for supporting the base components and means for exerting a downward force on the respective leading article at a position downstream of the roller, in relation to the direction of movement, so as to tilt the article and raise its trailing end relative to the leading end of the next-following article.

24. An apparatus according to claim 23, in which the force-exerting means comprise a weighted arm.

25. An apparatus according to claim 23 or 24, in which the separation means include means for restraining the leading end of the next-following article against upward movement during tilting of the leading article.

26. An apparatus according to claim 25, in which the restraining means comprise a roller having a resilient surface and mounted above and in rolling contact with the sequence of articles.

27. An apparatus for producing a plurality of articles each having a layer of extrudable material disposed upon a base component, substantially as hereinbefore described with reference to the accompanying drawings.

28. An article when made upon an apparatus arranged according to any of claims 18 to 27.