METHOD AND APPARATUS FOR ROLLING UP FLAT PIECES OF DOUGH, E.G. FOR SWISS ROLLS

Abstract: For rolling up pieces of dough (4, 5) for e.g. Swiss rolls, it has been a problem to obtain a safe and quick rolling up by means of an overlying conveyor belt (24), which is moved obliquely between a frontal, slim roller (18) and a rear driving roller (12). The invention solves this problem by the slim roller (18) being fitted with pronouncedly protruding prongs or ribs (32) and by the conveyor belt consisting of strings (34) with carriers (40) which are led around the slim roller (18) in grooves (38) in this roller.

Description: Method and apparatus for rolling up flat pieces of dough, e.g. for Swiss rolls. Α The present invention relates to a method for rolling up pieces of dough, e.g. baked and spread dough pieces for Swiss rolls. So far these operations have mainly been carried out manually, even in large, specialized baking firms with an industrialized production. There have been attempts at mechanizing this operation, e.g. with the use of a rolling cloth, but this proved extremely difficult, partly because problems arose at the commencing phase of the actual rolling up of the dough member because a mechani¬ cal affect often tends to result in just a successive folding of the dough member, and partly because known pro¬ posals for reasonably efficient machines have left some¬ thing to be desired as to reliability of operation. However, a method has already been proposed which is suited for a simple and partly efficient mechanical i plementation viz. by placing the front edge of the flat dough member in contact with a conveyor belt passing upwardly over the dough member in a suitably inclined position, whereby the conveyor belt may frictionally engage the dough member edge and may succeed in effecting an initial real rolling of the member, whereafter a further rolling up is effected by virtue of the continued engagement between the rolled up member portion and the conveyor belt, the inclination of which should just mainly correspond to the increase of the diameter of the rolled up portion as the rolling pro¬ ceeds rearuardly towards the opposite end of the dough member. This method, however, is not fully efficient, and * it has been connected ith a recommendation of causing the front end of the dough member to be lifted for securing a * safe initial engagement in order to increase the operational safety. Such lifting, however, involves mechanical compli¬ cations and requires an increased cycle time. According to another attempt the conveyor belt has been provided with protrusions, but still without the problem being solved. The present invention provides for a solut on simply and efficiently by using for the conveyor belt a number of parallel strings, which are resilient and provided with abruptly protruding carrier members and are guided around a slim roller immediately next to the front edge of the dough member. Said roller having prongs or ribs, which are located between the strings and project from the roller farther than the said carrier members project from the strings. The front edge of the dough member is thus effected direct by these prongs or ribs for commencing a rolling up, and it has been found that a very high degree of safety of the initial and the following rolling is achievable, as the initial rolling may be established aided by a strong im¬ pact from the coarse protusions on the slim roller without the dough member as then being rolled up being affected by such coarse protrusions, though still by effective carriers on the strings. The invention which also comprises an apparatus for the implementation of the method will now be described in the following with reference to the drawing in which Fig. 1 is a schematic perspective view of an apparatus, known in principle, for rolling up Swiss rolls. Fig. 2 is a perspective view of an end portion of a con¬ veyor designed according to the invention. Figs. 3-6 are a series of lateral views illustrating the mode of operation of the apparatus. Figs. 7 and 8 are lateral views illustrating the manufactur¬ ing of conveyor strings and Fig. 9 is a schematic lateral iew showing a modified conveyor. The apparatus shown in Fig. 1 is placed projecting across a conveyor belt for supplying dough members 4 to be rolled up. The apparatus comprises a chassis 6 which is mounted in a fixed guiding support 8 in such a way that by means of a cylinder 10 it can be reciprocated along the conveyor belt 2. Above and outside the opposite side of the belt 2 the chassis 6 carries a belt roller 12 with an associated motor 14. At the shaft ends of this roller is mounted a hinged frame 16 which at its free end carries a slim shaft or roller 18 additionally carried by a gall s 20, the lat¬ ter be ng connected with the chassis 6 through a cylinder 22, which will thus define the height position of the slim roller 18. Around the rollers 12 and 18 is placed a belt 24, which is sufficiently flexible to pass around even the slim roller 18 and shows a rough surface. The roller 12 is placed raised above the conveyor belt 2 such that the lower run of the belt 24 passes obliquely upwards from the slim roller when this is lowered to a position immediately above the conveyor belt 2. The upper part of the chassis 6 is pivotally connected with the part supported by the guiding support 8 so that t can be swung up and down by means of a pair of cylinders 26, whereby the height position of the roller 12 can be adjusted as required. At its starting point the chassis 6 is positioned at its extreme right end position in the guiding support 8, and the slim roller 18 is raised somewhat above the conveyor belt 2. The dough members 4 are placed on this belt n such a way that their outer edge designated 5 is moved forward towards the area just below and inside the slim roller 18. To facilitate a current adjustment in this respect the chassis 6 may be fi ted ith means not shown for altering the length of the horizontal part of the chassis whereby the entire belt 24 can be displaced in the transverse direction of the conveyor belt 2. When a dough member 4 has been moved to a position under¬ neath the belt 24, the cylinder 22 is activated to lowering the slim roller 18, and the cylinder 10 is activated to moving the entire chassis 6 towards the left at the same speed as that of the conveyor belt 2. By the lowering of the roller 18 the belt 24 is brought to catch the edge of the dough member and the object will then be rolled up as shown at 28, after which the rolled up member will be rolled over the edge of the conveyor belt 2 to a suitable receiver device such as a separate conveyor belt 30. Thereupon the slim roller is raised and the entire chassis 6 is quickly moved to the right making the apparatus ready for receiving and handling the next dough member 4. The apparatus described here operates according to a prin¬ ciple suggested previously where the roller 18 is a smooth roller cooperating with a suitably fπ ' ctional belt 24. According to the invention, however, the roller 18, cf. fig, 2, is a toothed roller with prongs or ribs 32, while the conveyor belt is made up from a number of parallel strings 34, which are received in a peripheral groove 36 in the large roller 12 and in similar grooves formed by recesses 38 in the ribs 32 on the small roller 18. The strings are made from resilient plastic and are kept slightly resi lient' ly stretched between the rollers 12 and 18. The strings are fitted with carriers, which may be simple knots on the strings, but preferably more pronouncedly protruding carriers are used, such as projecting flanges 40 on tubular rivets 42 fastened permanently to the strings. The driving roller 12 may be provided with a number of longitudinal grooves for consistently or occasionally catching the carriers 40, thus ensuring a good driving engagement with the strings. When these are resilient, they can remain reasonably tight regardless of the varia¬ tions in length that may arise when the carriers pass around the rollers. Figs. 3-6 illustrate how the initial rolling up of a dough member 4 effected. The dough member is placed with its front edge 5 right underneath the roller 18, and when the roller is lowered the front edge area will be forced up¬ wards and towards the rear by the relevant rib 32 on the roller 18 while the strings as shown in fig. 4, will con¬ tribute to further a correct rounding of the area as they will to some degree act rearwardly conveying and be foεced resi liently down against the raised front edge ;f the dough member. Sooner or later during this course a carrier 40 will arrive at the area where the dough member is caught by the strings, see fig. 6, and hereby the rolling up area recei es an extra push, which supports the initial rolling up. This may well involve some noticeable tearing of the dough member, but this is insignificant as the frontal area will be hidden inside the finished product. Also during the further course of rolling up, the surface of the dough object will be regularly subjected to a driving influence from the carriers, but as the diameter of the roll increases, the associated scraping effect will gradually decrease and eventually be practically eliminated on the surface of the finished product. In a preferred embodiment the tubular rivets 42 are placed at a mutual distance of 2-3 cm on the strings 34, and the flanges 38 protrude 1/2-1 mm beyond the surface of the string, thereby crea ing a most efficient carrier effect on the object to be rolled up. The carrier effect of the roller ribs 32 and the rivet flanges can be so pronounced that it may be appropriate to carry out the actual initial rolling up at reduced speed, whereby the motor 14 should be controlled in such a way that it slows down when the frame - 16 is pivoted down and accelerates immediately upon the commencing catch between the fluted roller 18 and the object to be rolled up. The rivets 42 can be secured by tying a knot on the string behind them or by their being deformed for fixing to the string. Preferably, however, a mounting method as illustrated in fig. 7 is used. A string 34 of a resilient thermoplastic mater al is used, the end parts of which are heated and extended to a very decreased diameter as shown at 46. On the end part 46 a number of tubular rivets 42 are pushed in, whereafter the string is heavily stretched between the outer end of the portion 46 and a squeezing tool 48. The diameter of the string s hereby reduced sufficiently for the rivets 42 to be easily pushed into their required positions on the string from the end portion 46. When the stretching of the string is discontinued, the string will expand so much that the ivets, consequently, will be very firmly secured only by the squeezing effect of the string, as is indicated to the left of the squeezing tool 48. The operational stretching of the string is moderate, i.e. the rivets will remain completely fixed during operation when they are suitably dimensioned. In fig. 8 another method for shaping carriers on the string 34 is indicated. Here it is shown how a thermoplastic string has been shaped with thickenings 50 by means of butt welding tools 52. It should be emphasized , however, that the inven¬ tion is not limited to specific designs of carriers. For certain applications it will even be sufficient that the strings or corresponding belts are provided with a defin te frictional surface without discrete carriers. Vice versa for other uses it may apply that pronounced carriers for the initial rolling up are required, while these during the final rolling up would be undesirably hard on the rolling up object. Fig. 9 shows how in such cases differentiat on can be obtained by applying an intermediate roller 54 from which strings 56 extend with a first kind of carriers down to the slim roller 18 and strings 58 with another kind or size of carriers extend up to the driving roller 12. Here it can be the intermediate roller 54 which is the driven roller, or other ise this roller can be sus¬ pended freely by the strings 56 and 58. By the embodiment shown in fig. 2 the possibi lity exists of interconnecting the strings with transverse threads to form a net structure, where the transverse threads may . optionally constitute carriers but such an arrangement cannot, of course, be used with the embod ment according to fig. 9. It is important that the prongs or ribs 32 on the front roller 18 are appreciably further protruding from the roller than those carriers which are led round the roller on the strings or belts 34. The cross sectional shape of the prongs or ribs 32 is not particularly critical, but as shown their shape is preferably rounded. There should be a reasonable spacing between the prongs or ribs, and as the roller 18 should furthermore have a small diameter in order to bring about a local lifting effect on the front area of the rolling up object, normally only four to eight prongs or ribs can be accommodated on the roller. The dough members to be rolled up normally have a thickness of 1/2-1 cm, and it would therefore be suitable for the ribs 32 to protrude 1 1/2-2 cm beyond the surface of the ro I Ler.

Claims: C L A I M S : •*s 1. A method for rolling up flat pieces of dough, prefer¬ ably baked and spread pieces of dough for Swiss rolls, whereby a front edge area of the dough member is brought to a frictional engagement with a conveyor belt, which is moved over the dough member along a path upwardly inclined thereover so as to cause a progressive rolling up of the dough member from its front edge area, the conveyor belt near the front edge area being led around a slim sprocket roller situated immediately above a supporting surface for the dough member, characterized by the use of such a sprocket roller, which from a base diameter has substanti¬ ally protruding prongs or ribs, and by the use of a con¬ veyor belt substantially consisting of strings with carriers, which by their passing the sprocket roller are protruding therefrom less than the said prongs or ribs. 2. An apparatus for carrying out the ' method according to claim 1, characterized in that the frontal slim sprocket roller is provided with pronouncedly protruding prongs or ri , and that the conveyor belt consists of strings or belts having carriers, which at their passing said sprocket roller are protruding therefrom less than the fixed prongs or ribs on the roller. 3. An apparatus according to claim 2, in which the strings are fitted with abruptly protruding carriers, e.g. consist¬ ing of flanges on tubular rivets. 4. An apparatus according to clai 2, in which the strings are made of a resi lient material. 5. An apparatus according to claim 2 in which the sprocket roller, as seen in its circumferent al direction is pro¬ vided with 2-10 protruding prongs or ribs. 6. An apparatus according to claim 2, in which the cai— riers on the strings consist of flanges on tubular rivets, which are secured on the strings by a resilient expanding effect of the strings acting against the inside of the tubular rivets.

Inventors: VOETMAN NIELS, VOETMAN, NIELS
Applicants: VOETMAN KARIN GLASSAU, VOETMAN, KARIN, GLASSAU
Application year: 1987
Main classification: A21C3
IPC codes: A21C3, A21C15, A21D8