the apparatus of the first embodiment of this invention will now be explained by referring to fig1 and 2 . it consists of a freezing chamber 7 , a melting chamber 8 , a forming conveyor 5 , a transfer conveyor 9 , and stretching means 10 . in the freezing chamber 7 , a mixing bowl 2 , a hopper 4 , and a part of the forming conveyor 5 , are provided . passages 1 , for feeding powdered dough materials and ice into the mixing bowl 2 , are provided at the top of the freezing chamber 7 . a pair of mixing blades 3 is provided at the end of a shaft downwardly extending into the mixing bowl 2 . the shaft and and bowl 2 are pivoted on brackets 21 and 22 , respectively . the bracket 21 is mounted to the inner wall of the freezing chamber 7 . the bracket 22 is mounted to an elevating means 20 that is fixed to the inner wall of the freezing chamber 7 so that the mixing bowl 2 can be moved up and down and turned upside down at desired angles , as illustrated by the broken lines in the figure . the hopper 4 is provided below the mixing bowl 2 for receiving mixed materials , namely , a dough mixture 6 . the forming conveyor 5 runs near the bottom of the hopper 4 and is composed of the conveying belt 51 wound around two end rolls , one of which is driven by a motor ( not shown ) and flexible walls 52 outwardly projecting from both the longitudinal edges of the conveying belt 51 . the flexible walls 52 can be made of rubber or many metal plates abutting end - to - end so that they can be move around the ends of the conveyor 52 . the hopper 4 rests on the upstream end of the conveyor 5 , as shown in fig2 . an outlet 41 for discharging the dough mixture 6 is provided at the bottom of the hopper 4 . in the freezing chamber 7 a subzero environment is maintained so that the powdered materials and the mixed dough mixture 6 are processed and stored in a powdery state . an opening is provided on the front wall of the freezing chamber 7 to transfer the formed dough mixture 6 &# 39 ; through it . adjacent the opening , on the outside of the freezing chamber 7 , is provided a melting chamber 8 . the temperature within the melting chamber 8 is maintained substantially above the freezing point . there are two methods of melting the particles of ice contained in the formed belt - like dough mixture 6 &# 39 ;, namely , one forcible and one natural . however , in this invention the forcible methods , such as the direct irradiation of a hot wind or microwaves to the formed dough mixtures 6 &# 39 ;, are effective . the melting chamber 8 works in the same manner as the above - mentioned opening for the freezing chamber 7 , and another opening is provided on its front wall . the forming conveyor 5 passes through these openings for the melting chamber 8 , and its downstream end projects outside . the transfer conveyor 9 , for carrying the formed hydrated belt - like dough mixture 6 &# 34 ;, is provided adjacent the end of the forming conveyor 5 . the transfer conveyor 9 is driven by a motor ( not shown ). a stretching means 10 is provided downstream of the transfer conveyor 9 . the stretching means consists of a plurality of conveyors , connected in series , that consist of an intake conveyor 11 , a middle conveyor 12 , and an outlet conveyor 13 and a group of rollers 14 . the rolls of conveyors 11 , 12 , and 13 are driven by respective motors ( not shown ) such that the speed of each of the plurality of conveyors is stepwisely increased in the downstream direction of progress of the sheeted dough . the rollers 14 are driven by a mechanism ( not shown ) such that each revolves while revolving in an elliptical orbit provided over and along the plurality of conveyors 11 , 12 , and 13 . the rollers 14 are driven by an assembly consisting of bevel gears , sprockets , and chain belts . the lower straight part of the elliptical orbit is spaced out a predetermined interval apart from the surface of the conveying belts of the plurality of conveyors 11 , 12 , and 13 so that the dough mixture passing therethrough is compressed and stretched . fig3 shows a stretching station 10 &# 39 ; of the second embodiment of this invention , which contains a plurality of the stretching means 10 and a folder 18 . in the stretching station 10 &# 39 ; a predetermined length of the stretched dough mixture is continuously folded by the folder 18 , and then repeatedly stretched , so that a highly - elastic bread dough with a well - developed gluten is obtained . the folder 18 is disposed adjacent the previous take - out conveyor 13 . it provides an oblong channel through which the sheeted dough is passed . the channel is driven by a mechanism ( not shown ) to be moved in the forward and backward directions along the course of the progress of the bread dough , so that the dough discharged on the conveyor is folded as shown in the figure . the folded dough is then stretched by the second stretching means 10 to form a dough sheet . fig4 shows the third embodiment of this invention , which uses another stretching means 10 &# 34 ;. this stretching means 10 &# 34 ; consists of a roll 15 and a conveyor 16 . the roll 15 reciprocates on a straight path spaced apart a certain interval apart from the surface of the conveying belt of the conveyor 16 , while rolling at a speed substantially synchronized with that of the conveyor 16 . the dough mixture being carried on the conveyor 16 is stretched in the direction of the progress of the dough mixture by the reciprocating movements of the roller 15 . the operation of the embodiments of this invention will now be explained . in the mixing bowl 2 , after the powdered materials , including flour and other materials , are uniformly mixed with particles of ice , the mixing bowl 2 is lowered and turned upside down to discharge the dough mixture 6 into the hopper 4 . the dough mixture 6 is formed into a belt - like shape by the forming conveyor 5 and then discharged from the outlet 41 of the hopper 4 . since the flexible walls 52 are provided on both sides of the forming conveyor 5 , the belt - like dough mixture 6 &# 39 ;, in a powdery state , does not fall from the sides . when the belt - like dough mixture 6 &# 39 ; passes through the melting chamber 8 , the particles of ice are thawed to make the belt - like dough mixture 6 &# 39 ; hydrated , and the hydrated dough mixture 6 &# 34 ; is moved onto the transfer conveyor 9 . the hydrated belt - like dough mixture 6 &# 34 ; is stretched , while its upper surface is pressed down by the rollers 14 , and a shearing stress , which is generated by the differences in the speeds of conveyors 11 , 12 , and 13 , is exerted on it . this causes a shearing deformation in the tissue structure of the dough mixtures so that a gluten network is generated . further , when the rollers 14 , which revolve over a common orbit , move on the lower straight part of the orbit , they strike the dough mixture . this results in the same effect as mentioned above , and generates a gluten network . the reciprocating roller 15 , shown in fig4 also shows a stretching effect that generates a shearing deformation similar to that mentioned above . namely , the rolling movements of the roller 15 , whose speed is substantially synchronized with that of the conveyor 16 , cause a shearing deformation to be generated during the progress of the dough mixture . the following table shows the formulation ratios of raw materials , namely , the ingredients for french bread dough , in an embodiment of this invention : ______________________________________ingredients ( parts by weight ) ______________________________________enriched wheat flour ( 12 % wheat protein ): 100 . 0yeast : 3 . 0sugar : 2 . 0shortening : 2 . 0dough conditioner : 1 . 8water : 55 . 0______________________________________ the following table shows the processing conditions of an embodiment of this invention : ______________________________________processing conditions______________________________________mixing and kneading time : 10 minconveying speed of intake conveyor : 4 m / minconveying speed of middle conveyor : 8 m / minconveying speed of outlet conveyor : 16 m / mindough thickness at intake conveyor : 50 mmdough thickness at outlet conveyor : 20 mmtemperature in melting chamber : about 60 - 70 c . average particle size of flour : 100 micronsrange of particle size of ice : 20 - 500 microns______________________________________ although the embodiments of this invention are explained relative to bread dough , they are also effective to manufacture other kinds of dough for pastry , pizzas , or noodles . as explained above , the method and apparatus of this invention eliminate the conventionally required kneading step , and enable the instant production of a sheet of bread dough of a high quality with a uniform width and thickness . the efficiency of producing bread dough is greatly improved by this invention . this brings about a great industrial effect in the field .
a method and apparatus for producing a sheet of dough , wherein powdered materials , including flour , yeast , sugar , and fats and oils , for making bread , are mixed with particles of ice , such that the particles of ice do not melt , to make them into a dough mixture . the dough mixture is formed into a continuous belt - like dough mixture having a uniform width and thickness such that the particles of ice do not melt , and then the particles of ice are melted to make the belt - like dough mixture hydrated . finally continuous hydrated belt - like dough mixture is stretched so that a continuous sheet of dough having a gluten network is provided .