Patent Publication Number: US-11643321-B2

Title: Door and baffle interface assembly for frozen dessert machines

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 17/075,964, filed on Oct. 21, 2020 (issued as U.S. Pat. No. 11,286,152), which is a continuation of U.S. patent application Ser. No. 16/394,276, filed Apr. 25, 2019 (issued as U.S. Pat. No. 10,894,708), which claims priority from United States Provisional Application No. 62/665,764, filed on May 2, 2018, the entirety of each are hereby incorporated by reference herein in their entirety 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The subject invention is directed to frozen dessert machines, and more particularly, to a mechanical interface between a detachable cantilevered baffle and a freezer door of a frozen desert machine. 
     2. Description of Related Art 
     Machines for continuously freezing soft serve desserts are well known in the art Most of these machines operate on a similar principle. A mixture of milk, sugar, gelatin, flavoring, coloring, nuts, fruits, syrups and sometimes eggs is fed into a metal cylinder or mixing chamber around which a compressed gas is expanded, making the metal surfaces of the mixing chamber very cold. Ice crystals form on the surface of the chamber and they are scraped off by sharp blades revolving around the interior of the chamber. Part of the scraping assembly is a beating arrangement that introduces air into the mixture, increasing its volume. The scraping assembly also moves the frozen dessert to the discharge spout associated with the door of the mixing chamber. 
     In frozen dessert machines sold by Taylor Commercial Foodservice, LLC located in Rockton, Ill., the scraping assembly is operatively associated—with a cantilevered baffle that extends into the mixing chamber from the door of the freezer. In prior art soft serve dessert machines of this type, the cantilevered baffle is usually made from stainless steel and it has a threaded protrusion at its end that is used to affix the baffle to the interior surface of the freezer door, which is made from a plastic material unlike the baffle. 
     This metal-to-plastic threaded interface exhibits high field failure rates—when subjected to a typical daily heat treatment cycle, during which the dessert product remaining within the mixing chamber is pasteurized at a temperature of between 150° F. to 160° F., and then cooled. This daily heat treatment cycle places stress on the threaded interface between the door and baffle, which tends to degrade the plastic door over time. 
     It would be beneficial therefore, to provide an interface between the door and baffle that could withstand the mechanical stress associated with a daily heat treatment cycle, and thereby effectively reduce or otherwise eliminate the high field failure rates that are currently being experienced in the marketplace. The subject invention provides such a solution. 
     SUMMARY OF THE DISCLOSURE 
     The subject invention is directed to a new and useful frozen dessert machine, and more particularly, to a novel mechanical interface assembly between a cantilevered baffle and the door of the frozen dessert machine to which it is affixed, which effectively reduces or otherwise eliminates the high field failure rates currently being experienced in frozen dessert machine in the marketplace. 
     The mechanical interface assembly of the subject invention includes a freezer door having opposed front and rear sides. At least one recessed mounting pocket is formed in the rear side of the freezer door, and the at least one mounting pocket has a cornice covering an upper portion thereof. 
     The interface assembly further includes at least one elongated baffle having opposed proximal and distal end portions. The proximal end portion of the at least one baffle includes a retention flange that is dimensioned and configured for detachable reception within the at least one mounting pocket of the freezer door behind the cornice covering the upper portion thereof. 
     The at least one mounting pocket in the rear side of the freezer door has a generally U-shaped configuration. The cornice that covers the upper portion of the at least one mounting pocket is preferably attached to the rear side of the freezer door by threaded fasteners, and a lower edge of the cornice is beveled. Alternatively, the cornice may be formed integral with the rear side of the freezer door. 
     The at least one baffle is preferably formed from a molded plastic material, which is similar to the material from which the freezer door is formed. Preferably, the least one baffle is formed from a self-lubricating thermoplastic material, such as Delrin or a similar material. 
     The retention flange of the at least one baffle has a generally U-shaped configuration that corresponds to the configuration of the at least one mounting pocket in the freezer door. Preferably, an upper edge of the retention flange of the at least one baffle is beveled to cooperate with the beveled lower edge the cornice covering the upper portion of the at least one mounting pocket in the freezer door. 
     The at least one baffle has a central portion with a cross-sectional configuration that is adapted to enhance the blending of the dessert product by an associated rotatable beater. In one embodiment of the invention, the central portion has a generally cruciform cross-sectional configuration. In another embodiment of the invention, the central portion has a trilobular cross-sectional configuration. A generally cylindrical hub region is integrally formed on the proximal end portion of the at least one baffle for rotatably supporting the beater. An annular thrust bearing is also integrally formed on the proximal end portion of the at least one baffle between the cylindrical hub region and the retention flange for interacting with the beater. In addition, a generally cylindrical support region is integrally formed on the distal end portion of the at least one baffle for maintaining the concentricity of the baffle relative to the beater within a freezing cylinder. 
     In an embodiment of the invention, the freezer door includes a pair of recessed mounting pockets formed in the rear side thereof, and each mounting pocket has a cornice covering an upper portion thereof, and an elongated baffle is detachably associated with each recessed mounting pocket formed in the rear side of the freezer door. 
     These and other features of the subject invention will become more readily apparent to those having ordinary skill in the art to which the subject invention appertains from the detailed description of the preferred embodiments taken in conjunction with the following brief description of the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that those skilled in the art will readily understand how to make and use the subject invention without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to the figures wherein: 
         FIG.  1    is a perspective view of a frozen dessert machine that includes one mixing chamber and a single spout freezer door; 
         FIG.  2    is a perspective view of a frozen dessert machine that includes two mixing chambers and a three spout freezer door; 
         FIG.  3    is an exploded perspective view of the frozen dessert machine of  FIG.  1    with certain parts separated for ease of illustration, including the freezer door and its associated baffle, as well as the beater assembly; 
         FIG.  4    is an exploded perspective view of the frozen dessert machine of  FIG.  2   , with certain parts separated for ease of illustration, including the freezer door and its associated baffles, as well as the beater assemblies; 
         FIG.  5    is a perspective view of the freezer door of the frozen dessert machine of  FIG.  1    with the baffle separated therefrom to illustrate the threaded interface that exists between these two components; 
         FIG.  6    is a perspective view of the freezer door of the frozen dessert machine of  FIG.  2   , with the two baffles threadably affixed to the door; 
         FIG.  7    is a perspective view of the freezer door of the frozen dessert machine shown in  FIG.  1   , illustrating the recessed mounting pocket formed therein and the cornice which covers an upper portion of the recessed mounting pocket; 
         FIG.  8    is a perspective view of the cantilevered baffle of the subject invention, which includes a retention flange that is dimensioned and configured for reception within the mounting pocket of the freezer door shown in  FIG.  7   ; 
         FIG.  8 A  is a cross-sectional view of the cantilevered baffle taken along line  8 A- 8 A of  FIG.  8   , illustrating the generally cruciform cross-sectional configuration of the central portion of the baffle of the subject invention, which includes a retention flange that is dimensioned and configured for reception within the mounting pocket of the freezer door shown in  FIG.  7   ; 
         FIG.  8 B  is a cross-sectional view of an alternative embodiment of the cantilevered baffle, illustrating the generally trilobular cross-sectional configuration of the central portion of the baffle; 
         FIG.  9    is an assembled perspective view of the cantilevered baffle of  FIG.  8    detachably retained in the recessed mounting pocket of the freezer door of  FIG.  7   , in accordance with the subject invention; 
         FIG.  10    is an assembled perspective view of two of the cantilevered baffles of  FIG.  8    detachably retained in the recessed mounting pockets of a freezer door, in accordance, with the subject invention, wherein the cornice associated with the upper portion of each mounting pocket is formed integral with the freezer door; 
         FIGS.  11  through  13    are a series of side elevational views, in cross-section, that illustrate the method of detachably securing the cantilevered baffle of  FIG.  8    to the freezer door of  FIG.  7   , in accordance with a preferred embodiment of the subject invention; and 
         FIG.  14    is a cross-sectional view taken along line  14 - 14  of  FIG.  10   , illustrating the integrally formed cornice associated with the upper portion of the mounting pocket formed in the freezer door. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings wherein like reference numerals identify similar structural elements and features of the subject invention, there is illustrated in  FIGS.  1  and  2   , two different versions of soft serve dessert machines manufactured and sold by Taylor Company, a division of Carrier Commercial Refrigeration, Inc. located in Rockton, Ill. These are examples of the type of machines for which the door and baffle interface assembly of the subject invention was specifically designed. 
     More particularly,  FIG.  1    shows a soft serve dessert machine designated generally by reference numeral  100  that includes a single spout freezer door  110  and a single mixing chamber  112  for blending a dessert product. Similarly,  FIG.  2    shows a soft serve desert machine designated generally by reference numeral  200  that includes a three spout door freezer door  210  and two mixing chambers  212   a  and  212   b  for two different flavors of frozen dessert product. These two machines  100 ,  200  are merely exemplary of the dessert machines that are manufactured and sold by Taylor Company, and should not be viewed in anyway as limiting the scope of the subject disclosure. 
     These soft serve dessert machines require scheduled cleaning and sanitizing, often governed by statute and local regulatory agencies. Indeed, many of the soft serve dessert machines manufactured and sold by Taylor Company, such as the machines  100  and  200  illustrated in  FIGS.  1  and  2   , provide a daily heat treatment cycle to safely maintain dairy products contained therein up to two, weeks, before a complete disassembly of the machine is required. 
     During the heat treatment cycle, the dessert product remaining within the mixing chambers of the machines is pasteurized at a temperature of between 150° F. to 160° F., and then cooled. This treatment method increases efficiency, decreases labor time and costs and reduces product waste. However, as explained in more detail below, repeated daily heat treatment cycles can cause certain critical components in these machines to undergo a significant amount of stress and fatigue, which can result in mechanical failures, taking the machines out of service until they can be repaired. 
     Referring now to  FIG.  3   , there is illustrated the soft serve dessert machine  100  with certain prior art component parts separated from the dessert machine for ease of illustration. More particularly,  FIG.  3    illustrates the mechanical components that are associated with the single spout freezer door  110  of dessert machine  100 . These components include an elongated cantilevered baffle  116  which is affixed to the rear surface of the freezer door  110 , an annular door gasket  118  for sealing the freezer door relative to the freezing chamber  142 , and a cylindrical bearing  120  which slides over the baffle  116  to rotatably support the front end portion of a helical beater  122 . The helical beater  122  includes a plurality of scraper blades  124 . The blades  124  are configured to scrape frozen dessert product from the interior surfaces of the freezing cylinder  142  and move that product toward the spout  144  on freezer door  110 . 
     The mechanical components associated with freezer door  110  further include a beater drive shaft  126  and a drive shaft seal  128  that seals the end of the drive shaft  126  to the rem of the freezing cylinder or chamber  142 . The beater drive shaft  126  has a rectangular head portion  130  that is dimensioned and configured to fit within a correspondingly shaped hole  132  on the rear end of the beater  122 , to engage the two components together. In use, the beater drive shaft  126  transfers torque and rotational motion to the beater  120  from a motor housed within the dessert machine  100 . 
     Referring now to  FIG.  5   , the prior art cantilevered baffle  116  includes a cylindrical hub portion  134  and an elongated U-shaped rod portion  136 . A threaded protrusion or post  138  extends from the front end of hub portion  134  for threaded engagement with a corresponding threaded bore  140  formed in the rear surface of freezer door  110 . The baffle  116  is made from stainless steel, while the freezer door  110  to which it is affixed, is made from plastic. This metal-to-plastic threaded interface between the plastic door  110  and the metal baffle  116  exhibits high field failure rates when subjected to a daily heat treatment cycle described above. The subject invention was developed to overcome this problem, as explained in more detail below. 
     Referring back to  FIG.  3    in conjunction with  FIG.  5   , the cylindrical bearing  120  is dimensioned and configured to fit over the hub portion  134  of the baffle  116 , and it includes a front flange  146  that acts as a thrust bearing between the freezer door  110  and the front end of the helical beater  122 , which will tend to exert a force against the freezer door  110  when the dessert machine  100  is in operation. 
     Referring now to  FIG.  4   , there is illustrated the soft serve desert machine  200  with certain prior art component parts thereof separated for ease of illustration. More particularly,  FIG.  4    illustrates two sets of common mechanical components that are associated with the three spout freezer door  210  of dessert machine  200 . For the sake of brevity, these components include cantilevered baffles  216   a ,  216   b  affixed to three spout freezer door  210 , annular door gaskets  218   a ,  218   b  for sealing the freezer door  210  with respect to the mixing chambers  242   a ,  242   b , cylindrical bearings  220   a ,  220   b  (with front flanges  246   a ,  246   b ) for rotatably supporting and interacting with the helical beaters  222   a ,  222   b  (with scraper blades  224   a ,  224   b ), beater drive shafts  226   a ,  226   b  which engage and drive the beaters  226   a ,  226   b , and associated drive shaft seals  228   a ,  228   b  that sealingly interact with the rear of the freezing cylinders  242   a ,  242   b.    
     Referring to  FIG.  6   , each of the cantilevered baffles  216   a ,  216   b  of dessert machine  200  includes a cylindrical hub portion  234   a ,  234   b  and an elongated U-shaped rod portion  236   a ,  236   b . A threaded protrusion or post  238   a ,  238   b  extends from each hub portion  234   a ,  234   b  for threaded engagement with corresponding threaded bores  240   a ,  240   b  formed in the rear surface of the freezer door  210 . These baffles  216   a ,  216   b  are made from stainless steel, while the freezer door  210  to which they are threadably affixed is made from plastic. Once again, this metal-to-plastic threaded interface exhibits high field failure rates when subjected to a daily heat treatment cycle. 
     Referring now to  FIG.  7   , there is illustrated a single spout freezer door constructed in accordance with a preferred embodiment of the subject invention and designated generally by reference numeral  310 . Freezer door  310  is designed for use with dessert machine  100  shown in  FIG.  1   , and it is similar to the single spout freezer door  110  shown in  FIG.  3   , except that freezer door  310  has a generally U-shaped recessed mounting pocket  350  formed in the interior or rear surface thereof. 
     The recessed mounting pocket  350  is located within the periphery of annular groove  352  that accommodates the door gasket  118 , which is shown in  FIG.  3   . A cornice  354  covers an upper portion of the mounting pocket  350 . The cornice  354  is attached to the rear side of the freezer door  310  by a pair of threaded fasteners  356 , as shown. Alternatively, the cornice may be formed integral with the rear side of the freezer door  310 , as described in more detail below with reference to  FIGS.  10  and  14   . 
     Referring to  FIG.  8   , there is illustrated a cantilevered baffle constructed in accordance with a preferred embodiment of the subject invention and designated generally by reference numeral  360 . Unlike the prior art baffle  116  described above and shown in  FIG.  5   , baffle  360  is molded from a plastic material, not stainless steel. Preferably, the baffle  360  is formed from a self-lubricating thermoplastic material, such as, for example, Delrin, which exhibits high stiffness, low friction and dimensional stability when subjected to heat. 
     The baffle  360  has a one-piece integral construction that includes a cylindrical front hub portion  362  having, an annular thrust bearing  364 , an elongated central portion  366  and a generally cylindrical support region  368 . The central portion  366  of the baffle  360  has a generally cruciform cross-sectional configuration, which is best seen in  FIG.  8 A . The cruciform shape aids in mixing dessert product within the core of the beater  122 , and is an enhancement over the U-shaped portion  136  of prior art baffle  116 . In an alternative embodiment of the baffle  360 , the elongated central portion  366  has a generally trilobular cross-sectional configuration, as illustrated in  FIG.  8 B , which is also an enhancement over the prior art baffle  116 . 
     The front hub portion  362  of baffle  360  supports rotation of the front end of the helical beater  122  and the integral thrust bearing  364  provides a bearing surface between the front end portion of the beater  122  and the freezer door  310 . The cylindrical support region  368  of baffle  360  interacts with the beater drive shaft  126  to aid in keeping the baffle  360  concentric with the beater  122  and the freezing cylinder  142 . By integrating these mechanical features into the one-piece baffle  360 , there is a reduction in component parts relative to the prior art mechanical assembly shown in  FIG.  3   . 
     With continuing reference to  FIG.  8   , the front end of the baffle  360  is formed with a retention flange  370  that has a generally U-shaped configuration, which corresponds to the U-shaped configuration of the recessed mounting pocket  350  in the freezer door  310  shown in  FIG.  7   . More particularly, the retention flange  370  is dimensioned and configured for reception within the mounting pocket  350  of the freezer door  310  behind the cornice  354 , as best seen in  FIG.  9   . It should be appreciated that an upper edge  372  of the retention flange  370  of baffle  360  is rounded or beveled, and a lower edge  374  of the cornice  354  covering the upper portion of mounting pocket  350  in freezer door  310  is angled or beveled (see  FIG.  11   ). This eases the engagement of the retention flange  370  behind the cornice  354  of the mounting pocket  350 , which will be described in more detail below with reference to  FIGS.  11 - 13    below. 
     The U-shaped interface between the retention flange  370  of baffle  360  and the mounting pocket  350  of freezer door  310 , prevents the baffle  360  from rotating relative to the freezer door  310  when the beater  122  is in motion during machine operation. Moreover, this plastic-to-plastic interface, which is shown in  FIG.  9   , is not susceptible to the stress and fatigue that has impacted the metal-to-plastic threaded interface of the prior art metal baffle  116  and plastic freezer door  110 , as a result of repeated heat treatment cycles. 
       FIG.  10    illustrates the same mechanical interface described above as to  FIG.  9   , but for a three spout freezer door  410  designed for use with dessert machine  200  shown in  FIG.  2   , which supports two of cantilevered baffles  360   a ,  360   b . Here, the freezer door  410  of the subject invention has two generally U-shaped mounting pockets  450   a ,  450   b  formed in the interior or rear surface thereof. The mounting pockets  450   a ,  450   b  corresponding to freezing cylinders  242   a ,  242  be of frozen dessert machine  200 . As an alternative to the separate cornice  354  shown in  FIG.  9   , the embodiment of  FIG.  10    provides integrally formed cornices  454   a ,  454   b  covering the upper portions of mounting pockets  450   a ,  450   b.    
     Referring now to  FIGS.  11  through  13   , there are illustrated a series of side elevational views, in cross-section, that illustrate the method of affixing the cantilevered baffle  360  to the freezer door  310  of frozen dessert machine  100 , in accordance with a preferred embodiment of the subject invention. More particularly,  FIG.  11    shows the initial positioning of the beveled upper edge  372  of the retention flange  370  of baffle  360  below the beveled lower edge  374  of the cornice  354  of mounting pocket  350  of the freezer door  310 . 
       FIG.  12    shows the initial engagement of the retention flange  370  of baffle  360  behind the cornice  354  of mounting pocket  350 , and  FIG.  13    shows the angular pivoting of the baffle  360  into a final detachably engaged position of the retention flange  370  of baffle  360  within the mounting pocket  350  of freezer door  310 , securely retained behind the cornice  354 . This plastic-to-plastic mechanical interface assembly between the baffle  360  and the door  310  effectively reduces or otherwise eliminates the high field failure rates currently being experienced in the marketplace with respect to the prior art baffle  116  that is threadably affixed to the freezer door  110 . 
     While the subject disclosure has been shown and described with reference to preferred embodiments, those skilled in the art, will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.