Abstract:
An apparatus for joining dough blocks to form a continuous dough sheet. The dough blocks are cut from a dough mass and drop into a space between first and second groups of rollers. The first and second groups of rollers include horizontally-paired rollers arranged in tiers and forming a substantially V-shaped space for receiving the dough blocks, with the uppermost pair of rollers being separated by a first horizontal gap which is wider than a second horizontal gap separating the lowermost pair of rollers. The first group of rollers are rotated in a direction (e.g., clockwise) which is opposite to that of the second group of rollers. In addition, the first group of rollers is alternately moved toward and away from the second group of rollers, thereby applying vibrations to the dough blocks. The combined rotation and vibrations of the rollers impels the dough blocks downward toward the second gap between the lowermost pair of rollers and increases gluten growth and a joining of the gel structures to produce a continuous dough sheet.

Description:
BACKGROUND OF INVENTION 
     1. Field of Invention 
     The present invention relates to a method and an apparatus for joining separated blocks of dough, and for supplying a continuous sheet of dough formed from the joined dough blocks. In particular, the present invention relates to a method and apparatus for joining a first kneaded dough block to a subsequently-provided kneaded dough block such that the gel structures of the dough blocks are integrally joined to form a continuous dough sheet on a production line. 
     2. Prior Art 
     In a conventional apparatus, a plurality of dough sheets are formed by pressing individual kneaded dough blocks, and then portions of each dough sheet are cut away to produce, for example, bread products. Each dough sheet has a volume corresponding to the volume of the kneaded dough block from which it was formed. The entire dough sheet is used in one production lot, or each part of the dough sheet is used in a production lot. When one dough sheet is used in a production lot, production time is lost between the adjacent dough sheets when they are fed by a conveyor. Also, fragments which remain after portions of the dough sheet are cut away are not used during production. 
     In a conventional apparatus, if necessary, adjacent dough sheets are joined to each other by a manual operation. That is, a rear end of a dough sheet is piled on a front end of a subsequently-formed dough sheet, and then the piled ends are manually pressed such that they adhere to each other. There is no apparatus to perform this sheet joining operation. Thus, the operation must be manually performed whenever a gap appears between sequentially-formed dough sheets, so that a significant amount of manual labor is needed to perform the joining operation. In bread production lines, unmanned production is usually performed to make bread from dough sheets that have the same conditions in their degree of composition and kneading, because technology to make a thin dough sheet has been improved and is now broadly used. However, when many kinds of breads that have several shapes and additional ingredients, such as fillings, are made on the same production line, much manual work is needed to join sequentially-formed dough sheets. 
     A gel structure is formed in a dough mass during a mixing operation. When the dough mass is cut to form individual dough blocks, the gel structure of each dough block is separated from the dough mass and from all previously-formed dough blocks. Thus, in order to join two separated dough blocks, it is necessary to join their gel structures. Currently, there is no apparatus for automatically joining the gel structures of two dough blocks. 
     SUMMARY OF INVENTION 
     An object of the present invention is to overcome the disadvantages of the prior art. 
     In accordance with the present invention, a method and apparatus are provided for automatically joining a first dough block to a subsequently-formed dough block, so that a very long and continuous dough sheet is automatically made, and so that unmanned production over a 24 hour period is achieved. 
     The present invention allows gel structures of dough blocks to be automatically joined to each other. This invention also allows several kinds of breads to be produced during a non-stop production process. In a conventional apparatus there are many production lots corresponding to the mixing operations of the dough. This invention allows a continuous dough sheet corresponding to one production lot to be made. Thus, this invention allows segmentation of douch sheets to be minimized. Also, this invention minimizes the time between the processing of subsequently-formed dough sheets. 
     One object of the present invention is to provide a method and apparatus for joining dough blocks to each other. The apparatus comprises horizontally and oppositely-positioned pairs of rollers provided in a plurality of tiers. The rollers are arranged such that the distances between the roller pairs in the upper tiers are sequentially greater than the distances between the roller pairs in the lower tiers, thereby forming a “V” shaped space for receiving the dough blocks. Each pair of rollers is rotated in an opposite direction such that a surface of each roller facing the “V” shaped space pushes the dough blocks downward. In addition, the distances between the roller pairs are alternately increased and decreased, thereby causing a pressure applied to the dough blocks by the rollers to alternately increase and decrease to produce a vibrations in the dough blocks as the dough blocks are impelled downward. The resulting thixotropic effect in the dough produced by these vibrations accelerates the growth of gluten and the joining of gel structures of the dough blocks, and a continuous belt-like dough sheet is thereby formed. 
     The method uses horizontally and oppositely positioned pairs of rollers provided in a plurality of tiers. The rollers are arranged such that the distances between the roller pairs of the upper tiers are sequentially greater than the distances between the roller pairs of the lower tiers, thereby forming a “V” shaped space for receiving the dough blocks. The method includes rotating the rollers of each pair in opposite directions while alternately increasing and decreasing the distances between the rollers of each pair such that a pressure applied by the rollers to the dough blocks is alternately increased and decreased, thereby impelling the dough blocks downward. The resulting vibrations in the dough produced by this pressing and releasing action accelerates the growth of gluten and the joining of gel structures of the dough blocks, and a continuous belt-like dough sheet is thereby formed from the dough blocks. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic side view of a bread production apparatus that includes a first embodiment of an apparatus for joining dough blocks according to the present invention. 
     FIG. 2 is an enlarged schematic side view of the apparatus shown in FIG.  1 . 
     FIG. 3 is a schematic side view for explaining operation steps of the apparatus shown in FIG.  2 . 
     FIG. 4 is a schematic side view for explaining operation steps of the apparatus shown in FIG.  2 . 
     FIG. 5 is a schematic side view of a second embodiment of the apparatus for joining dough blocks according to the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows a bread-making apparatus that includes an apparatus  1  for joining dough blocks in accordance with a first embodiment of the present invention. A bowl  2  mixes and kneads materials to make a dough mass  4 . The dough mass  4  is supplied from the bowl  2  onto a conveyor or a dough feeder  3 . The dough feeder  3  feeds the dough mass  4  to a set of rotatable cutter blades  5 , which separates dough blocks  6  from the dough mass  4 . The dough blocks  6  are then supplied to the joining apparatus  1  in response to signals from a sensor  21  (shown in FIG.  2  and discussed below). The joining apparatus  1  joins dough blocks to each other to provide a continuous belt-like dough sheet  7  which is deposited from a lower opening of the joining apparatus  1  onto a first conveyor  8 . The dough sheet is continuous (i.e., not separated by gaps). The first conveyor  8  feeds the dough sheet  7  to a dough-extending apparatus  9 . The extending apparatus  9  presses and extends the dough sheet  7  to make a pressed dough sheet  10  having a predetermined thickness and width required for making desired bread products. The dough-extending apparatus  9  feeds the pressed dough sheet  10  to a second conveyor  11 . A depositing apparatus  12  is located above the second conveyor  11  so as to supply a filling, such as jam or meat, onto the pressed dough sheet  10 . A cutting apparatus  13  is positioned over the second conveyor  11 . The cutting apparatus  13  moves vertically to cut the pressed dough sheet  10  into pieces  14 , each piece  14  having a desired length and width. Also, the cutting apparatus  13  may provide desired shapes to the pieces  14 . Then resulting dough pieces  14  are continuously output from the cutting apparatus  13 . 
     FIG. 2 is an enlarged view of a part of the bread-making apparatus shown in FIG. 1. A hopper  22  is positioned at the forward end of the dough feeder  3 . 
     The rotatable cutter blades  5  are positioned at a bottom opening of the hopper  22 . The joining apparatus  1  is located under the opening of the hopper  22  and the rotatable cutter blades  5 . A sensor  21  is positioned near an upper opening of the joining apparatus  1 , and senses whether an amount of dough in the joining apparatus  1  decreases to such an extent that the upper surface of the dough is below a predetermined level in the joining apparatus  1 . When the sensor  21  senses the surface of the dough in the joining apparatus  1  is below a predetermined level, it outputs a signal. In response to this signal, the dough feeder  3  is driven to feed the dough mass  4  into the hopper  22 . Simultaneously, the dough cutter blades  5  are rotated. When the dough mass  4  is supplied from the dough feeder  3  to the hopper  22 , a dough block  6  is cut from the dough mass  4  by the blades  5 , which are located at the bottom opening of the hopper  22 , thereby causing the dough block  6  to have a predetermined volume. The cut dough block  6  drops into the upper opening of the joining apparatus  1 . As a result, the amount of dough in the joining apparatus  1  is increased such that an upper surface of the dough is above the predetermined level. 
     The joining apparatus  1  includes a first roller group  20  including rollers  23 ,  24 ,  25  and  26 , and a second roller group  20 ′ including rollers  23 ′,  24 ′,  25 ′ and  26 ′. In the embodiment shown in FIG. 2, each roller of the first and second groups  20  and  20 ′ is cylindrical, and is shown in end-view in FIG.  2 . The rollers  23 - 26  are parallel and aligned in a first row, and the rollers  23 ′- 26 ′ are also parallel and aligned in a second row. The first and second rows of rollers are arranged to form a “V” shaped space for receiving the dough blocks  6  cut by the blades  5 . Each roller of the first group is arranged opposite to a corresponding roller of the second group in a horizontal plane or tier. For example, rollers  23  and  23 ′ are arranged in an uppermost tier and are separated by a first horizontal gap forming the upper opening of the joining apparatus  1 . Likewise, rollers  26  and  26 ′ are arranged in a lowermost tier and are separated by a second horizontal gap forming the lower opening of the joining apparatus  1 . The first horizontal gap is greater than the second horizontal gap. The remaining opposing roller pairs (that is,  24  and  24 ′, and  25  and  25 ′) in the respective intermediate tiers are spaced apart to form the “V” shaped space. In addition, the rollers of the first group  20  are rotated in an opposite direction from the rollers of the second group  20 ′ by a suitable driving means (not shown) such that the dough blocks therebetween are pushed downward. For example, as indicated in FIG. 2, the rollers of the first group  20  are rotated clockwise, while the corresponding rollers of the second group are rotated counter-clockwise. In addition to rotating, each roller reciprocally swings or linearly moves toward and away from its opposing roller. Thus, the rollers in an opposite roller pair are alternately moved toward and away from each other in a horizontal plane, so that the gaps between them are repeatedly increased and decreased. When the opposing rollers move toward each other, pressure on the dough therebetween is increased. When the opposing rollers move away from each other, the pressure is decreased. The rate of movement of the opposing rollers is selected such that the repeated increase and decrease in pressure applied to the dough produces vibrations which create a thixotropic effect in the dough. As a result, the gluten in the dough increases and the gel structures of the dough blocks are joined to each other. 
     The circumferential speeds of the lower rollers of the groups are lower than those of the upper rollers of the groups. However, the circumferential speeds of all of the rollers may be the same. Also, the speeds of the rollers of one group may differ from those of the rollers of the other group. 
     FIG. 3 shows the joining apparatus  1 , in which the circumferential speeds of the lower rollers of the groups are lower than those of the upper rollers. For example, the speeds of the rollers  25 ,  25 ′, and  26 ,  26 ′ are lower than those of the rollers  23 ,  23 ′ and  24 ,  24 ′. Parts of the surfaces of each dough block  6  that contact the upper rollers  23 ,  23 ′, and  24 ,  24 ′ are drawn downward as the rollers rotate. Then, these parts and/or other parts of the surface of each dough block  6  that contact the lower rollers  25 ,  25 ′, and  26 ,  26 ′ are drawn to the lower opening of the joining apparatus  1 . Thus, the parts of the dough block  6  that contact the upper rollers flow faster than those that contact the lower rollers. 
     However, parts of each dough block  6  located in the middle of the “V” shaped space between the opposite roller pairs (that is, parts which do not contact any roller) flow faster than the parts that contact the rollers. This occurs because the pressure applied by the opposing roller pairs to each dough block  6  when the opposing rollers approach each other forces the dough blocks downward toward the lower opening, rather than the dough blocks being drawn by the rotations of the rollers  23 ,  23 ′,  24 ,  24 ′,  25 ,  25 ′,  26 , and  26 ′. Thus, as shown in FIG. 3, parts of each dough block  6  that do not contact the rollers and that are generally positioned at the middle between each opposing roller pairs flow faster than those that contact the rollers. 
     In detail, a lower surface of a dough block  6  is generally flat (horizontal) when the dough block is supplied from the hopper  22  onto the top surface of a previously-supplied dough block located in the joining apparatus  1 . As the dough block is drawn downward into the joining apparatus  1 , the lower surface of the dough block  6  that contacts the upper surface of the previously-supplied dough block descends at a higher rate at the mid-point between the opposing roller pairs such that the dough block becomes V-shaped. This V-shaped layer is gradually elongated as the dough block  6  descends further into the joining apparatus  1 , so that the surface areas of adjacent dough blocks that contact each other are increased. Then, the layer extends longitudinally. Simultaneously, the roller pairs move toward and away from each other to press the dough block and release the pressure from the dough block, so that the contacted surfaces are vibrated by the motions of the rollers. As a result, the adhesion between the contacted surfaces of the adjacent dough blocks is increased. Also, the receding and approaching movements of the rollers function as a tapping motion on the dough blocks, resulting in generating a thixotropic effect. Thus, the flowage of the dough is increased and the joining of the gluten in the dough is accelerated. Finally, the joining apparatus  1  supplies a continuous and belt-like dough sheet  7  through the lower opening onto the first conveyor  8 . 
     FIG. 4 shows the joining apparatus  1 , in which the circumferential speeds of the rollers of one group differ from those of the rollers of the other group. That is, the circumferential speeds of the rollers  23 ,  24 ,  25 , and  26  of the group  20  are faster than those of the rollers  23 ′,  24 ′,  25 ′, and  26 ′ of the group  20 ′. As a result, as shown in this figure, the parts of each dough block  6  that contact the rollers  23 ,  24 ,  25 , and  26  are drawn down faster by these rollers than the parts of each dough block  6  that contact the rollers  23 ′,  24 ′,  25 ′, and  26 ′. Thus, each separated dough block  6  is modified to form long continuous dough layers. The movements of the rollers toward and away from each other increases adhesion between the dough layers. Then, the joining apparatus  1  supplies a continuous and belt-like dough sheet  7  to the first conveyor  8 . 
     FIG. 5 shows another embodiment, namely,  1 ′, of the joining apparatus  1  as in FIG.  1 . It includes a group  50  of rollers  51 ,  52 ,  53 , and  54  and the group  20 ′ of the rollers  23 ′,  24 ′,  25 ′, and  26 ′. The cross-sectional shape of each roller of the group  50  is hexagonal. These hexagonal rollers impel the dough with a stronger force than the cylindrical rollers, so that each separated dough block  6  is modified more effectively into long continuous dough layers along the longitudinal direction of the flow of the dough. The long continuous dough layers extending in the longitudinal direction of flow of the dough have large contact surfaces. Thus, the resulting thixotropic effect unites the gel structures of the dough layers. 
     Polygonal rollers may be used for the sectional shape of the rollers. Also, polygonal rollers may be used for the upper rollers of the joining apparatus  1  in FIG. 1, so that the same effects as is the case as in FIG. 4 can be generated. 
     In the above embodiments, either or both of the group  20 ′ of the rollers  23 ′,  24 ′,  25 ′, and  26 ′ and the group  20  of the rollers  23 ,  24 ,  25 , and  26  or either or both of the group  20 ′ of the rollers  23 ′,  24 ′,  25 ′, and  26 ′ and the group  50  of rollers  51 ,  52 ,  53 , and  54  is/are reciprocally swung or linearly and reciprocally moved. However, this invention is not limited to these configurations. For example, the distances between the opposite roller pairs may be changed so that their pressing movements are sequentially generated between them from above downwards. Also, the distances between the opposite roller pairs may be alternately changed in the vertical direction such that the pressing movements between the opposite roller pairs are alternately effected in the vertical direction. 
     By this invention gel structures in respective dough blocks are joined to each other by repeatedly providing pressing and vibrating operations to the dough blocks, so that the dough blocks are deformed and piled upon each other to form layers. Thus, a continuous belt-like dough web is formed.