GB2204775A

GB2204775A - Chocolate coating machine

Info

Publication number: GB2204775A
Application number: GB08807614A
Authority: GB
Inventors: Manfred Puderbach
Original assignee: Winkler & Dunnebier KG
Current assignee: Winkler & Dunnebier KG
Priority date: 1987-03-30
Filing date: 1988-03-30
Publication date: 1988-11-23
Anticipated expiration: 2008-03-30
Also published as: DE3710539A1; GB8807614D0; GB2204775B

Description

1 1 J 1 2204775 Coating Machine This invention relates to a coating

machine for example for coating confectionery articles with cocoacontaining, tempered and flowable compositions, particularly chocolate, and desirably equipped with a transport device for the confectionery articles in the form of a widemeshed grid band, coating devices within a coating circuit for surface and/or bottom coating, a decrystallizer and a precrystallizer and a compactlyconstructed supply and feed device which include supply containers for uncrystallized and precrystallized compositions, composition pumps, composition conduits.

Coating machines are used for coating confectionery articles with the flowable compositions, particularly with tempered chocolate.

Known coating machines have at least one device for bottom coating and at least one device for surface coating. A plurality of supply containers are necessary to supply these devices with chocolate, a first, larger container for uncrystallized chocolate, a second container for precrystallized chocolate and a smaller one in each of the bottom coating device and the surface coating device. In general, the two small supply containers are fixedly installed with their respective coating devices in the coating machine, whilst the supply containers for uncrystallized and precrystallized chocolate are arranged in the machine so that they can be partially moved out. With the aid of a first pump chocolate is transferred from the first, larger supply container for uncrystallized and supply and 1 2 chocolate into the second supply container for precrystallized chocolate via a conduit system in which a decrystallizer and a precrystallizer are incorporated. The precrystallized chocolate moves from here via a second pump with a downstream three-way valve and conduits connected thereto to the surface or bottom coating device from where it is applied to the confectionery articles. Superfluous chocolate, ie chocolate not carried by the confectionery articles, is returned to the second supply container. The f irst pump, which is disposed upstream, is so set as regards its transfer volume that precrystallized chocolate flows back continuously from the second into the first supply container through an overflow. A level switch disposed in the first supply container controls the composition supply from a stationary factory tank.

In an alternative construction of a coating machine the supply container for uncrystallized chocolate is fixedly arranged outside the machine. This container is larger and serves simultaneously as a melting container. It is connected to a second supply container for precrystallized chocolate by means of a conduit system in which a f irst pump and a precrystallizer are incorporated. The surface and also the bottom coating device are supplied from here with crystallized chocolate via a second pump with a downstream three-way valve and conduits connected thereto. From here, the chocolate reaches the confectionery articles, the superfluous chocolate which has not been taken up f lowing subsequently back into the second container. More chocolate is always supplied to the second container than is required for coating the confectionery articles. A level switch 3 4 arranged in the second container ensures in conjunction with a third pump and a return line connected thereto that superfluous chocolate composition is pumped back into the melting container so that the second container always has the same amount of crystallized chocolate.

With known coating machines of this type there are disadvantages, principally that they have a large number of necessary supply containers, and their associated and expensive tube conduits, valves and pumps. The mechanical shearing of the chocolate thus increases which makes itself felt both in an increasing number of air inclusions by bubble formation and also in a temperature rise due to frictional heat. Both lead to a reduction in the quality of the coated confectionery article. Furthermore, the large filling volume in the internal composition circuits is problematic when changing the coating composition. Finally, it should be noted both that maintenance work and work required when changing the coating composition prove to be time consuming and thus very costintensive due to the large installation complexity.

It is an object of the invention to provide a compactly constructed and economical supply and feed device for the coating devices of a coating machine which is easy to service and which furthermore reduces or eliminates the disadvantages of the prior art.

The object is solved in accordance with the invention if the supply container of-the bottom coating device is so constructed that it simultaneously serves as the supply container for the precrystallized composition situated in the coating circuit.

Thus. according to the present invention there is provided a coating machine for coating confectionary 1 f 4 articles with tempered and flowable compositions comprising a conveyor arranged to transport items to be coated to an upper coating device for coating the upper surface of the items and a bottom coating device for coating the lower surface of the items, a pump arranged to circulate precrystallized composition around a circuit including the upper coating device, the lower coating device and a first supply container for precrystallized composition, the first supply container serving simultaneously as a supply container for the bottom coating device.

Further advantageous features of the invention will be apparent from the description and the claims in conjunction with the drawings.

The advantage obtained with the invention resides particularly in that compared with the conventional construction an expensive supply container and associated valves are omitted in the solution in accordance with the invention. At the same time, the amount of chocolate composition in the coating circuit is thereby reduced. By virtue of its compact construction, the supply and feed device can be decoupled from the coating machine and easily moved out manually, this increasing the servicability and resulting in a large time saving when changing the composition. It has also been found to be advantageous if a separate supply and feed device can be kept available for each sort of chocolate if this is rendered necessary by the operational procedure.

Furthermore, when the supply and feed device has been moved out a simple cleaning of the application roller of the bottom coating device is possible due to improved accessibility. Finally, it is also 1 4 advantagegus that the chocolate composition can be f ed back rapidly from the supply container for precrystallized composition into the supply container for uncrystallized composition by means of any emptying device. This is particularly useful when changing the composition or in the daily start of production.

The invention will be described in more detail below with reference to an exemplary embodiment, which is illustrated in the drawings, which show:

Figure 1: a schematic side view of the coating machine, I Figure 2: a front view showing the main features with the supply and f eed device moved out and shown in chain dotted lines, Figure 3: a view of the emptying device on an enlarged scale, and Figure 4: a quick release connection in detail.

Figures 1 and 2 show in an extremely schematic representation the basic construction of a coating machine 1. A support device 3 in the form of an endless grid band 4 runs over guide rollers 5 and tension roller 15. On its upper, horizontal run 4' it transports a product track 2'. which comprises confectionery articles 2 which are to be coated, in the direction of the arrow 7 through a housing 8 of the coating machine 1. The housing has slit-like inlet and outlet openings 8' and 8' for the confectionery articles 2 and internally disposed heating elements, which are not described in detail. Behind the inner opening 8' below the run 4' there is a bottom coating device 9 and above the run 4' a surface coating device 10. The service coating device 10 is mounted so as to be movable vertically and horizontally together with a 1 1 6 succeeding blowing nozzle 11 on a guide 12' within the housing 8. Downstream behind the bottom coating device 9 and directly beneath the run 4' there is a vibration guide 12 which is driven by a vibration producer 13. Behind the vibration guide 12 the grid band 4 is tangential with a scraper device 16.

Arranged below the bottom coating device 9 and the run 4' of the grid band 4 is a supply and feed device 14 for the coating devices 9 and 10. This may be seen separately in Figure 2 in the moved out state in addition to the chain dotted representation. Vertically projecting support walls 20 and 21 are provided on a movable wagon 17 which has a horizontally aligned support plate 19 carried by rollers 18. Secured to the lower region of the support wall 20 and resting on the support plate 19 is a larger supply container 22 for uncrystallized chocolate. A smaller supply container 23 for precrystallized chocolate is horizontally arranged above the supply container 22. The former rests on two brackets 24 and 25 and is fixed, together with these, to the support wall 20. Seen in the direction of the arrow 7 the supply container 23 is broader than the grid band 4 but narrower than the supply container 22. It has lateral overflows 23' leading towards the supply container 22. It further includes an internal stirring device 26, which comprises an endless grid band 27, which rotates continuously around two rollers 28 and 29. The grid band 27 is tangential along its upper run 27' with an applicator roller 45 of the bottom coating device 9. A drive 30 for the stirring device 26 is mounted externally on the support wall 20 opposite the supply container 23. An emptying device 32, which is not j 7 shown in detail in Figure 3, is integrated in the bottom wall 31 of the supply container 23.

The supply container 22 has a stirring device 33 which is driven by the drive 30 by means of a chain wheel 34 and a roller chain 35. Arranged within the supply container 22 is a level switch 36 which serves to ensure a constant filling with uncrystallized chocolate.

The supply container 22 is filled with conched, uncrystallized chocolate from a Main factory tank via a composition conduit 37. A magnetic valve, which is not shown, is included in the composition conduit 37 which is controlled by the level switch 36 to permit or stop the chocolate supply. The chocolate is f ed from the supply container 22 via a composition conduit 38 to a composition pump 39 which pumps it through a composition conduit 40 to a decrystallizer and a precrystallizer connected thereto whi.ch are both arranged outside the coating machine 1 and are thus not shown in the drawings. The structure of the chocolate is broken down in the decrystallizer at about 500C and is thereafter cooled (tempered) to about 300C, depending on its type, in the precrystallizer, whereby it again forms crystal nuclei. The chocolate which is now precrystallized and is under the transfer pressure of the composition pump 39 flows through a composition conduit 41 into a further conduit 42, which connects the supply container 23 to a composition pump 43 secured to the side wall 21. The freshly precrystallized chocolate is sucked up by the composition pump 43 through the composition conduit 42 together with the chocolate flowing back from the supply container 23 and pumped via a composition 1 8 conduit 44 into a supply container 10' of the surface coating device 10. The entire chocolate mass corresponding to the output of the composition pump 43 flows out of the surface coating device 10 in the form of chocolate slurry onto the product track V. The chocolate which is not taken up by the confectionery articles 2 flows through the grid band 4 back into the supply_container 23. From here it is in part fed from the upper run 27' of the grid band 27 to the applicator roller 45. In front of the tangent point, formed by the roller 45 and the run 27', a bead of chocolate is produced which is responsible for the application to the applicator roller of a chocolate film. The chocolate is transferred by the applicator roller 45 to a bottom wall plate 46 which is arranged directly beneath the upper run 4' of the grid band 4 and serves there to bottom coat the confectionery articles 2. The chocolate which is not taken up by the confectionery articles 2 also flows back again into the supply container 23. The coated confectionery articles 2 move with the grid band 4 subsequently through a blowing and vibration stage 11' and 12. In this they are freed of excess chocolate so that a uniform chocolate coating is achieved. Subsequently, the bottoms of the confectionery articles and the grid band 4 are levelled and cleaned, respectively, by means of a scraper device 16. The chocolate flowing or dripping away in the blowing, vibration and scraping processes is collected by a collecting plate 47 and carried back into the supply container 22 by the run 4 ' ' of the grid band 4 sliding above the collecting plate 47.

The transfer volume of the composition pump 39 is so sized that it always transfers more than the 9 confectionery articles 2 can take up so that chocolate continuously flows back out of the supply container 23 through the overflow 23' into the supply container 22. The transfer volume of the composition pump 43 is normally set three or four times as large as that of the composition pump 39. In this manner a continuous circulation is produced and a good mixing of the precrystallized chocolate composition in a coating circuit which is formed starting from the composition pump 43, via composition conduit 44,, surface coating device 10, supply container 23 and through composition conduit 42 back to the composition pump 43.

The coating machine 1 is also suitable for providing the confectionery articles 2 with a halfcoating. For this purpose it is sufficient to turn off the composition pump 43 so that the chocolate composition which comes from the precrystallizer and is under the transfer pressure of the composition pump 39 is forced from below into the supply container 23 through the composition conduits 41 and 42. The application onto the confectionery articles 2 occurs by means of the bottom coating device 9 in the manner already described.

For the purpose of moving out the supply and feed device 14, the rigidly installed composition conduits 40 and 41, which lead back to the decrystallizer and from the precrystallizer, are constructed to be rapidly separable. For this purpose commercially available quick-release connections 40' and 41' are provided which are shown in Figure 4 as a single unit.

The emptying device 32 of the supply container 23 is shown in more detail in Figure 3. In the bottom wall 31 of the supply container 23 there is an opening k 31 ' which may be closed by means of a movably jointed flap 48. The flap 48 has an annular eye 48' with which it is retained rotationally fixed on a shaft 49. The shaft is rotatably mounted in a bearing 52 which is secured externally to the supply container 23. A double-acting cylinder 50 which may be acted on by a pressure medium acts via a lever 51, which is also rotationally fixed to the shaft 49, on the flap 48. By means of operating elements arranged externally on the machine 1, (but not illustrated) the cylinder 50 is so controlled that the flap 48 is opened or closed. The emptying device 32 of the supply container 23 is principally required in the daily start of production. In this, the flap 48 remains open until optimally free crystallized chocolate is delivered from the precrystallizer.

It is course well known that to persons skilled in this art that the supply containers, pumps and most of the composition conduits of the coating machine 1 have devices for maintaining the temperature or, if necessary, for temperature regulation. For this reason, they are preferably of double wall construction and a heating or cooling medium, in accordance with requirements, flows through them.

1 A v 11

Claims

CLAIMS:

A coating machine for coating confectionery articles with tempered and flowable compositions comprising a conveyor arranged to transport items to be coated to an upper coating device for coating the upper surface of the items and a bottom coating device f or coating the lower surface of the items, a pump arranged to circulate precrystallized composition around a circuit including the upper coating device, the lower coating device and a first supply container for precrystallized composition, the first supply container serving simultaneously as a supply container for the bottom coating device.
2. A coating machine as claimed in Claim 1 including feeding means comprising a second supply container for uncrystallized com position, a decrystallizer and a precrystallizer supplied with composition from the second supply container, and a conduit arranged to supply the resultant precrystallized composition to the circuit.
3. A coating device as claimed in Claim 2 in which the first supply container is disposed generally under the conveyor and a second supply container is disposed generally under the first.
4. A coating device as claimed in Claim 3 in which the first supply container has at least one overflow to the second supply container (22).

1
5. A coating device as claimed in Claim 2 or Claim 3 in which the f irst and second supply containers are supported by at least onecommon supporting wall.
6. A coating device as claimed in any one of Claims 2 to 5 including means for emptying the f irst container into the second container.
7. A coating device as claimed in Claim 6 in which the means for emptying the first container comprises an opening in the base of the first container which is closable with a flap.
8. A coating device as claimed in Claim 7 in which the flap is arranged to be actuated by an actuating cylinder.
9. A coating machine as claimed in any one of Claims 2 to 8 in which the first and second supply containers are commonly mounted to a wagon which can be moved away from the conveyor.
10. A coating machine as claimed in Claim 9 in which the wagon also carries the circulating pump, and a further pump arranged to supply composition to the circuit.
11. A coating machine as claimed in Claim 9 or Claim 10 in which the first supply container contains a stirring device comprising an endless grid band which rotates around two rollers.
12. A coating machine as claimed in Claim 11 in which 13 the wagon also carries a drive for the stirring device.
13. A coating machine as claimed in any one of Claims 9 to 12 in which the wagon is selectively lockable in a fixed position with respect to the conveyor.
14. A coating machine as claimed in any one of Claims 9 to 13 in which the wagon may be selectivelydecoupled.
15. A coating machine as claimed in Claim 14 in which quick-release connectors are provided on conduits leading to and from the wagon.
16. A coating machine as claimed in anyone of the preceding claims in which the circuit further includes a third supply container for the upper coating device.
17. A coating device as claimed in any one of the preceding claims arranged for coating chocolate.
18. A coating device substantially as specifically described, with reference to the drawings.

Published 1988 at The Patent Office, State House, BBP71 High Holborn, London WCIR 4TP. Further copies maybe obtained from The Patent Office, Wes Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, St Maxy Cray, Kent. Con. 1/87.