Abstract:
The invention relates to a forming and cooling device for a flowable, melted food mass  1 , more particularly processed cheese, comprising two parallel, oppositely rotating cooling belts  2, 3 , which are each guided over an upper  4  and a lower  5  deflection roller and are separated from each other in order to form a continuous strip  6  of the food mass, wherein the cooling belts  2, 3  are each acted upon by a cooling fluid  7  on the side facing away from the strip, characterized in that a tubular supply channel  8  is formed at the upper region of each cooling belt  2, 3  and is equipped with a plurality of outlet conduits  9  arranged side by side, the central recess of which is cylindrically formed and by way of which a laminar, non-turbulent cooling-liquid stream  10  can be placed upon the cooling belt  2, 3.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on international patent application no. PCT/EP2010/007617 filed on 14 Dec. 2010, which claims priority from German patent application no. 102010007984.7 filed on 15 Feb. 2010. 
     BACKGROUND OF THE INVENTION 
     (1) Field of the Invention 
     The invention relates to a forming and cooling device for a flowable, melted food mass. 
     Specifically, the invention relates to a forming and cooling device as is generally known from DE 103 28 905 A1. 
     (2) Description of Related Art 
     DE 103 28 905 A1 shows a device, as depicted in  FIG. 1 , in which a melted food mass  1 , more particularly processed cheese, is rolled and cooled to form a continuous strip  6 . To this end, the device comprises two oppositely rotating, endless cooling belts  2 ,  3 , each of which is guided over an upper deflection roller  4  and a lower deflection roller  5 . The two cooling belts  2 ,  3 , which are preferably designed as steel belts, are spaced apart from one another in order to form the strip  6  of the food mass (processed cheese). 
     Each side of the cooling belts  2 ,  3  facing away from the strip  6  of food mass is acted upon by a cooling fluid  7  in order to cool the melted food mass. 
     The cooling of the food mass requires uniform cooling and good dissipation of the heat quantity introduced by the food mass. It is also necessary to supply and drain off the cooling fluid (water) in a reliable manner. 
     The problem addressed by the invention is that of creating a device of the initially-mentioned type that ensures reliable cooling while having a simple design and simple, cost-favorable manufacturability and that is characterized by a high degree of operational dependability. 
     BRIEF SUMMARY OF THE INVENTION 
     The problem is solved according to the invention by forming and cooling device for a flowable, melted food mass ( 1 ), more particularly processed cheese, comprising two parallel, oppositely rotating cooling belts ( 2 ,  3 ), which are each guided over an upper ( 4 ) and a lower ( 5 ) deflection roller and are separated from each other in order to form a continuous strip ( 6 ) of the food mass, wherein the cooling belts ( 2 ,  3 ) are each acted upon by a cooling fluid ( 7 ) on the side facing away from the strip, characterized in that a tubular supply channel ( 8 ) is formed at the upper region of each cooling belt ( 2 ,  3 ) and is equipped with a plurality of outlet conduits ( 9 ) arranged side by side, the central recess of which is cylindrically formed and by way of which a laminar, non-turbulent cooling-liquid stream ( 10 ) can be placed upon the cooling belt ( 2 ,  3 ). The dependent claims show further advantageous embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is described in the following by reference to an exemplary embodiment in combination with the drawing. Shown are: 
         FIG. 1  a schematic side sectional view according to the prior art, 
         FIG. 2  a perspective partial view, in part as a sectional drawing, of a cooling belt with the supply and drainage of cooling fluid according to the invention, 
         FIG. 3  a simplified side view of the arrangement depicted in  FIG. 2 , 
         FIG. 4  an enlarged detailed view of the detail B according to  FIG. 3 , 
         FIG. 5  an enlarged detailed view of the detail C of  FIG. 3 , 
         FIG. 6  a simplified front view, in part as a sectional drawing, of the arrangement shown in  FIGS. 2 to 5 , 
         FIG. 7  a perspective depiction of an exemplary embodiment having an adjustable working width, and 
         FIG. 8  an enlarged, simplified sectional view according to the exemplary embodiment 7. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     According to the invention, a forming and cooling device for a flowable, melted food mass is therefore created, in which a tubular supply channel equipped with a plurality of outlet conduits arranged side by side is disposed at the upper region of the particular cooling belt. The outlet conduits are designed such that they place a laminar layer of cooling fluid upon the surface of the cooling belt. To this end, the outlet conduits are equipped with a cylindrical recess from which a laminar outflow of the cooling fluid results. According to the invention, the possibility is therefore created of applying the cooling fluid without the risk of spraying and of applying a cooling fluid having a uniform thickness and a constant width. In contrast to the prior art, the possibility is therefore created of applying the cooling film uniformly in terms of the thickness thereof and the width thereof and, therefore, of ensuring optimized heat transfer between the surface of the cooling belt and the preferably turbulently flowing cooling-fluid film. It is therefore not expected, as is partially the case in the prior art, that a non-uniformly distributed, turbulently flowing-off and inconsistently thick cooling-liquid film will form. 
     By way of the embodiment according to the invention it is therefore possible to carry out cooling uniformly from both sides. This is also advantageous in terms of uniform cooling and reliable formation of the strip of the food mass. 
     According to the invention it is particularly favorable when the supply channel forms a storage volume. As a result it can be ensured that the outflow of cooling fluid from the outlet conduits takes place in a slow, constant and laminar manner, while a turbulent flow formation can also be expected in the supply channel if pressure is higher and inflow conditions are unfavorable. The storage volume provided according to the invention, the pressure of which can be 0.05 bar to 0.3 bar, for example, ensures uniform outflow of the cooling fluid from all outlet conduits, thereby also resulting in consistent flow conditions across the entire width of the cooling belt. 
     According to the invention, the embodiment is therefore designed such that the cooling-water supply (flow) does not have an unfavorable effect on the outflow through the outlet conduits. More particularly, the kinetic energy of the inflowing flow and the pressure distribution do not restrict the outflow through the outlet conduits. 
     The outlet conduit is preferably arranged at an angle with respect to the surface of the cooling belt, for example at an angle between 40° and 60°. A particularly favorable placement of the cooling-fluid film takes place as a result. 
     Furthermore, it is favorable according to the invention that a plurality of outlet conduits is provided, which are distributed uniformly across the width of the cooling belt. The uniform, laminar fluid outflow and the formation of the uniform cooling-fluid film flowing down in a laminar manner is obtained as a result. 
     The outlet conduits preferably have a ratio of length to diameter of 5 to 9. Uniform flow is ensured as a result. 
     In order to remove the cooling fluid that runs off in the form of the cooling-fluid film from the surface of the cooling belt, it is particularly favorable according to the invention when a run-off element for draining off the cooling fluid is provided underneath the supply channel. The run-off element is preferably designed in the form of an outflow gutter through which the cooling fluid can be drained off in a spray-free and uniform manner due to the sufficient volume of the outflow gutter. It proves particularly favorable when the run-off element comprises a scraper bearing against the inner side of the cooling belt that is preferably elastically preloaded against the surface of the cooling belt. The scraper therefore removes the cooling-fluid film in a uniform manner. The scraper, the plug-and-socket connections of the scraper and the outflow gutter are designed smooth and free of interfering components (screws, for example) in the course of the inflowing cooling water, thereby allowing the cooling water to flow into the outflow gutter without spraying. 
     In order to permit replacement of the scraper in a simple manner and with little complexity if it should become worn, it is favorable when the scraper is supported at the run-off element by way of a plug-and-socket connection. 
     The drainage of the cooling-liquid film provided according to the invention does not require additional external energy, as would be the case, for example, for pumping away. Furthermore, the device is designed such that very little noise is produced. 
     A further, significant advantage of the device according to the invention is that the scraper can be supported at the run-off element in a floating manner due to the plug-and-socket connection thereof. As a result, no deformations of the scraper result due to a clamped connection or the like or due to temperature differences, and so leaks cannot form between the scraper and the surface of the cooling belt due to a deformation of the scraper (wavy deformation). 
     It is furthermore advantageous that the drainage of the cooling fluid takes place through the outflow gutter by way of gravity, and therefore no components need to be provided that are susceptible to interference and can fail. 
     In a favorable development of the invention it is provided that the supply channel is equipped with an adjusting device, by way of which a supply of cooling fluid to some of the outlet conduits can be adjusted. The effective working width of the cooling device can be adjusted by way of the adjusting device. It is possible, more particularly, to seal some of the outwardly lying outlet conduits with respect to the supply of cooling fluid, and so the cooling fluid only flows out of a central region of the cooling device. The application of the cooling fluid (cooling water) can therefore be adjusted in terms of width symmetrically and steplessly from both sides. In so doing it is particularly favorable when the adjusting device comprises at least one piston that is displaceable within the supply channel. Preferably two pistons are provided, in order to symmetrically seal the outlet conduits provided in the outwardly located end regions against an inflow of cooling fluid. Therefore, cooling fluid does not flow through said outlet conduits, but rather is discharged through the relevant outlet conduits only in the central region and is fed to the cooling belt. 
     The pistons are preferably actuated by way of a drive or even by a hand crank that comprises a spindle, for example, that can be actuated via a servo drive. The piston is thereby displaced within the housing of the supply channel, thereby permitting cooling fluid to flow only to the centrally disposed outlet conduits, while the outlet conduits positioned outside of the piston cannot be acted upon by cooling fluid. It is thereby made possible to perform an adjustment without the risk of spraying or dripping. The spindle is preferably equipped with a counter-rotating thread in order to move both pistons synchronously in a mirror image manner. 
     In a favorable development of the invention it is provided that a run-off opening is provided at each lateral end region of the supply channel, through which a desired leakage flow through the piston is drained. This leakage flow is also favorable for CIP cleaning since it is possible, as a result, to reliably clean the entire adjusting mechanism. 
     A further, essential advantage of the forming and cooling device according to the invention is that it is easy to clean. No hidden internal spaces result, but rather a uniform flow of cleaning fluid is possible, and so CIP (clean-in-place) cleaning, in particular, can take place, in which the components of the forming and cooling device according to the invention can also be used, in fact, for cleaning. 
       FIGS. 2 to 6  each show only one revolving cooling belt  2 ,  3 . As shown in  FIG. 1 , two interacting cooling belts  2 ,  3  are provided in each case in order to uniformly cool the gap between the two cooling belts  2 ,  3 , in which the strip  6  of food mass is formed. According to the invention, the entire system can also be designed such that the strip  6  of food mass lies on only one revolving cooling belt and, therefore, a second cooling belt is not required in this region. 
       FIGS. 2 ,  3  and  6  each show an upper deflection roller  4  and a lower deflection roller  5 , about which a endless cooling belt  2 , which is made of steel, for example, is guided. The cooling belt extends vertically, analogously to the depiction of  FIG. 1 . 
     According to the invention, a horizontally disposed, tubular supply channel  8  is provided in the upper region of the cooling belt, as shown in  FIG. 3 , which forms a storage volume and at which a plurality of outlet conduits  9  is provided, as  FIGS. 3 and 4  show in particular. The outlet conduits  9  are equipped with a cylindrical recess and are disposed at the tubular supply channel  8  such that a laminar cooling-fluid stream  10  results (see  FIG. 4 ), which produces a laminar cooling-fluid film  11 . The laminar cooling-fluid film  11  is formed by the plurality of outlet conduits  9  arranged side by side. 
     In the exemplary embodiment shown, the melted food mass is introduced, for example, at a temperature between 75° C. and 85° C., while the cooling fluid (cooling water) has a temperature of 1° C., for example. When the strip  6  of the cooling-medium mass emerges from the cooling belts  2 ,  3 , it has been cooled to a temperature between 5° C. and 10° C., for example. 
     As shown more particularly in  FIG. 4 , the laminar cooling-fluid stream  10  does not spray, but rather is placed evenly and uniformly against the surface of the cooling belt  2 . 
     The outlet conduit  9  has a length, for example, between 25 and 30 mm and an inner diameter between 3 and 4 mm. Overall, it is advantageous when a ratio of length to diameter between 5 and 9 results. 
     By way of the device according to the invention it is possible to apply a uniform cooling-fluid film  11  that flows off uniformly, expands laterally not at all or only insubstantially and adheres well to the surface of the cooling belt. Given a cooling wall width of 1200 mm, for example, cooling-water quantities between 2 m 3 /h and 4 m 3 /h can therefore be applied. 
       FIGS. 7 and 8  show a further exemplary embodiment of the invention. In this exemplary embodiment, the working width of the cooling device according to the invention is adjustable. It comprises a central region of the drain channel  8 , which is designed analogously to the first exemplary embodiment. Cooling fluid is supplied centrally by way of a connecting conduit  18 , which is not shown in detail. Lateral supply channels  8   b  are formed adjoining the central region of the supply channel  8   a . They are preferably designed as a two-piece housing, as shown in  FIG. 8 . Pistons  15 ,  16 , which can be displaced by way of spindles  18 , are displaceably supported in this housing. To this end, the spindles  18  are equipped with counter-rotating threads (not shown) and are guided in a spindle housing  20 . Connection to a servo drive is possible by way of a drive connection  21 . Rotation of the spindles  18  therefore results in linear displacement of the pistons  15 ,  16 . 
     As shown in  FIG. 8 , the supply channel  8  is equipped with a longitudinal recess  23 . Individual bores  22 , which direct cooling fluid to the outlet conduits  9 , branch off therefrom. As shown in the depiction in  FIG. 7 , due to the sealing effect of the piston  15  and  16 , respectively, the bores  22  and, therefore, the outlet conduits  9  located laterally outside of the pistons  15 ,  16 , cannot be acted upon by cooling fluid. 
     To enable cleaning of the entire device, a leakage flow through the pistons  15 ,  16  is possible. Leakage fluid is fed laterally into run-off openings  17  (protruding pipes) and flow laterally onto the surface of the particular cooling belt. 
     By rotating the spindles having the counter-rotating threads at both ends, the pistons  15 ,  16  are therefore moved. The non-round design of the pistons  15 ,  16  prevents them from rotating therewith. Rather, the pistons are merely displaced. 
     As shown in  FIG. 4 , an additional scraper  14  can be provided above the tubular supply channel  8  in order to remove adhering fluid regions, if applicable, from the surface of the cooling belt before the cooling-fluid film  11  is applied. This can be appropriate in particular for cooling belts that run upwardly. The strippers (scrapers) above the application conduit on the upwardly running cooling belts have the purpose of wiping off cooling fluid that has been carried upward before it reaches the upper roller and therefore drips thereon. 
     According to the invention, the drainage of the cooling fluid takes place by way of a run-off element  12 , which is designed in the form of an outflow gutter  12  disposed at a slant (see  FIG. 6 ). It is open toward the top and can therefore be easily cleaned. The introduction of the cooling fluid or the removal of the cooling-fluid film  11  from the surface of the cooling belt  2  takes place by way of an elastic scraper  13  (see  FIG. 5 ), which is fastened on the run-off element  12  in a floatingly supported manner, preferably by way of a plug-and-socket connection. 
     The device according to the invention is open laterally at the cooling belt  2 ,  3 , it is not necessary to limit the laminar cooling-fluid film  11  by way of lateral webs or the like on the cooling belt  2 ,  3  since lateral stoppage of the laminar cooling-fluid film  11  does not take place. 
     According to the invention, the following advantages therefore result:
         a compact and simple design, easy to produce   exact application of the medium in terms of width and bounded in a straight manner (edge region)   CIP-capable without an additional conduit system, thermal stability during cleaning   compensation of surface irregularities in the cooling belt without malfunction   high temperature range possible without malfunction   application of the largest possible cooling water quantity   no complex control or regulation of pressure or flow volume, no complex nozzle shape   variability of the application quantity of 30-100% without the application system dripping or splashing   layer thickness uniform across the width   high functional reliability, no energy consumption, (no noise production)   no malfunction if the belt runs dry   fast replacement possible, minimal set-up effort   no damage to the steel belt, stability.       

     LIST OF REFERENCE CHARACTERS 
     
         
           1  food mass/processed cheese 
           2 , 3  cooling belt 
           4  upper deflection roller 
           5  lower deflection roller 
           6  strip of the food mass 
           7  cooling fluid 
           8  tubular supply channel 
           9  outlet conduit 
           10  laminar cooling-fluid stream 
           11  laminar cooling-fluid film 
           12  drain element/outflow gutter 
           13 ,  14  scraper 
           15 ,  16  piston 
           17  run-off opening 
           18  spindle 
           19  connecting conduit 
           20  spindle housing 
           21  drive connection 
           22  bore 
           23  recess