Abstract:
A thermal conditioning system for heating and cooling cylindrical containers includes a container heating apparatus with an enclosed heating chamber, transport mechanism for movement of the containers through the heating chamber, a cooling apparatus positioned below the heating chamber, and conveyor systems for introducing containers into the heating chamber and form removing the containers from the cooling apparatus after they have passed through the system.

Description:
BACKGROUND OF THE INVENTION 
   In the food processing and canning industry there has long been a requirement for heating and cooling the canned product. Various types of equipment have long existed for such thermal conditioning of containers, such as cans. Exemplary of such equipment is that shown in U.S. Pat. No. 1,445,196 to Berry and in U.S. Pat. No. 2,043,310 to Thompson. In such prior art equipment are passed along a first helical path within a heating chamber and are then moved to a separate cooling chamber along side the heating chamber. While this equipment performs its designed function, it is bulky and requires considerable space for installation, space which is frequently at a premium in a packing facility. Much of this prior art equipment has also presented difficulties in maintenance and cleaning due to the fixed housing for containing the cooking steam. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide an apparatus for heating and cooling cylindrical containers that overcomes the disadvantages of the prior art equipment. It is a further object of the invention to provide such apparatus that is rugged and durable and provides for simplified operation and cleaning. 
   To achieve the foregoing as well as other objects that will become apparent to those skilled in the art, a thermal conditioning system for heating and cooling cylindrical containers is disclosed and includes a container heating apparatus, a heating transport apparatus for supporting movement of the containers through the heating chamber, an introduction conveyor for introducing containers into the heating chamber from outside that chamber, container cooling apparatus positioned generally below the heating chamber, and an exit conveyor for moving the containers from the cooling apparatus to a location outside the heating apparatus and cooling apparatus. The container heating apparatus includes a heating chamber of generally cylindrical configuration with a generally vertical cylindrical axis, with that chamber including a housing enclosing the heating chamber and having a generally cylindrical configuration generally coaxial with the heating chamber axis, and a heating fluid introduced into the chamber for heating the containers within the heating chamber. The heating transport apparatus includes the plurality of generally circular tracks carried by track support and spaced apart from one another along the cylindrical axis, a transport mechanism for moving the containers around those tracks, and a transfer structure for moving the containers from one such track to an adjacent lower such track. The container cooling apparatus includes a cooling fluid spray, and transport apparatus generally coaxial with the heating chamber transport apparatus, with that transport apparatus further including a plurality of generally circular tracks carried by a track support and spaced apart from one another along the cylindrical axis, the first such circular track being positioned directly below the lowermost such heating apparatus track for receiving heated containers therefrom, and further includes a transport mechanism for moving the containers around the tracks, and a transfer structure for moving the containers from one such track to an adjacent lower track. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     To illustrate further the principles of this invention, a preferred embodiment will be described in detail in which: 
       FIG. 1  is a side elevation of one embodiment of the thermal conditioning apparatus of this invention; 
       FIG. 2  is a side elevation of the apparatus of  FIG. 1  with the housing and introduction conveyor removed to more clearly illustrate the internal structure; 
       FIG. 3  is a top plan view of the apparatus of  FIG. 1 , with the cylindrical heating chamber housing removed; 
       FIG. 4  is a sectional view of the apparatus of  FIGS. 1-3  taken along line  44  of  FIG. 3 , with the containers deleted from the transport apparatus to more clearly illustrate the structure; 
       FIG. 5  is a fragmentary sectional elevation taken along lines  5 — 5  of  FIG. 3 ; and 
       FIG. 6  is top plan view of the apparatus of  FIG. 1  with the cylindrical housing removed to illustrate more clearly the introduction of the containers into the heating apparatus transport mechanism and the removal of the containers from that transport apparatus. 
   

   DESCRIPTION OF PREFERRED EMBODIMENTS 
   A particularly preferred embodiment of the thermal conditioning apparatus of this invention is illustrated in the elevational view of FIG.  1 . This apparatus includes a heating chamber  10  of generally cylindrical configuration with a generally vertical cylindrical axis  12 . This heating chamber comprises a housing, which suitably comprises a plurality of axially adjacent sections, such as upper section  14  and lower section  16 , each having a generally cylindrical configuration and being generally coaxial with the heating chamber axis  12  and a generally circular top portion  13 . This heating chamber  10  is further provided with sources for introducing a heated fluid, such as steam, into the chamber. These sources may conveniently be pipes  18  and  20 , which are connected to conventional steam generators (not shown), to provide a supply of this heated fluid for heating the chamber  10 . 
   The apparatus of this system also includes an introduction conveyor  22  for introducing containers into the heating chamber from outside. The containers to be introduced are preferably of right circular cylindrical configuration, such as cans or canned food products. A ramp  24 , or other suitable structure, brings the containers, preferably with their cylindrical axes generally horizontal, to the introduction conveyor  22 . Conveniently, as shown in the drawings, the ramp  24  and conveyor  22  are configured to provide end-to-end pairs of the cylindrical containers  26  onto the conveyor  22  or, if desired, may provide for introduction of individual containers, or groups of three, four or more containers. The introduction conveyor  22  is of conventional construction and includes a plurality of flights, each spaced apart from the adjacent flight to receive one of the containers  26 , or, in this case, a pair of such containers end-to-end. As shown in  FIG. 1 , the introduction conveyor  22  preferably receives the containers  26  on a horizontal portion and then carries them in a generally vertical direction up to a location close to the top of the heating apparatus. As the containers are lifted in the introduction conveyor, they enter a closed channel  28 , which, in this embodiment, first runs vertically and then horizontally adjacent to the top of the apparatus, with the conveyor then returning back down through another vertical portion of the channel to the bottom of the equipment, as shown in FIG.  1 . 
     FIG. 2  is a side elevation of the apparatus of this invention, with the chamber housing removed to illustrate the structure within. Similarly,  FIG. 3  is a top plan view of this apparatus, with the heating chamber housing removed, and  FIG. 4  is a sectional elevational view taken along line  44  of  FIG. 3  to illustrate the components of the transport apparatus included in that heating chamber. As shown in  FIG. 2 , the heating transport apparatus includes a plurality of generally circular tracks  30 , shown in phantom on  FIG. 3 , that are carried by track supports  32  (shown most clearly in the fragmentary sectional view of  FIG. 5 , taken along line  5 — 5  of FIG.  3 ). 
   In the sectional elevational view of  FIG. 4  is illustrated the transport mechanism for moving the containers around these tracks  30 . The transport mechanism of this embodiment comprises a rotatably mounted cylinder or drum  36  having a generally vertical axis and mounted, suitably by means of a central shaft  38  and conventional bearings  40 , for rotation about this vertical axis. As shown on  FIG. 4 , the drum is rotationally driven by conventional means, such as a conventional electric motor or the like  48 , connected to the drum central shaft  38  by conventional means, such as pulleys and belts or chains and sprockets, which are well known to those in the art. Suitably, this drive motor  42  is also used to drive the introduction conveyor  22 , so that rotation of the cylinder  36  is synchronized with movement of the introduction conveyor  22 . 
   As shown in FIG.  4  and more clearly in the fragmentary sectional view of  FIG. 5 , there are attached to the rotating cylinder  36  a plurality of pusher elements  44  extending generally radially outwardly from the rotating cylinder  36  and positioned to engage the cylindrical containers  26 . Thus, rotation of the rotating cylinder  36  about its shaft  38  will urge the containers  26  around the circular track  30 . The radially outer ends of the pusher elements  44  adjacent a given track  30  are connected to a continuous ring  45 , as is shown in FIG.  5 . 
   As shown on  FIG. 2 , each of the circular tracks includes at one point an opening in the track with a ramp  46  extending angularly downwardly from one such track  30  toward the respective subjacent, or next lower track, such that containers moving around each track will, upon encountering the opening and ramp  46 , move down the ramp from the one circular track to the next subjacent track. In this manner the containers  26  that are being moved around the tracks will sequentially move to each lower track, until they are discharged from the entire apparatus. 
     FIG. 6  is a simplified top view similar to that of  FIG. 3 , but with the top cover of the housing removed and the circular track supports removed to illustrate the manner of movement of the containers  26  through the equipment. As the containers  26  are introduced from the ramp  24  onto the horizontal portion of the introduction conveyor  22 , they first move horizontally, and then vertically ( FIG. 1 ) up to a point adjacent to the top of the apparatus, where the conveyer again resumes a horizontal movement that overlaps the top circular track  30 . As described above, this conveyor includes a plurality of flights that push the containers  26  along a track  23 , which preferably has a flat bottom portion with sides extending generally perpendicular to that bottom portion to support the containers as they are moved by the conveyor flights. At the point where the transport conveyor  22  is directly above the topmost circular track, there is provided an opening  48  in that track  23 . That opening  48  permits the containers  26  to drop through that opening onto the immediately subjacent upper circular track, between adjacent pusher elements  44 . As noted above, the movement of the rotating cylinder  36 , and thus the pusher elements  44 , is synchronized with the movement of the flights of the introduction conveyor  22 . Once on this uppermost circular track, the containers  26  then move around that track until they encounter the opening and ramp  46  down to the next lower track, and then proceed through the heating chamber. While in that heating chamber, which is enclosed by the cylindrical segments  14  and  16 , the containers are subject to a heating fluid, such as steam, introduced through the conduits  18  and  20 . The steam effects heating of the interior of the heating chamber, and thus of the containers that are circulating through it. 
   As shown in  FIG. 1 , the heating chamber housing encloses the upper portion of the overall apparatus, with a lower portion, including a number of the circular tracks  30 , outside those cylindrical housings  14  and  16 . The heated fluid, such as steam, is contained in the enclosed portion, because of the heat tending to rise. As the steam may condense on the structures, it may drain to receptacles (not shown) below the apparatus. As the cylindrical containers  26  continue in their process through the apparatus, they ultimately proceed through an opening in one of the tracks at the lowermost portion of the heating chamber housing portion  16  to the next lower track, which is shown in  FIG. 1  to be outside that housing portion  16 . This group of cylindrical tracks below the heating chamber housing comprises the transport apparatus of the container cooling apparatus. This apparatus includes the circular tracks and their drive mechanism, including the cylinder  36  and pusher elements  44 , substantially identical to the transport apparatus in the heating chamber, and also a plurality of dispensers  50  dispensing a cooling fluid spray  52 , such as a cool water spray. The cooling fluid is supplied through a conventional conduit from a conventional source (not shown). As shown on  FIGS. 1 and 2 , when the containers reach the lowermost track  30  that is within the heating chamber, the openings  48  in that track and at least the next adjacent lower track are positioned close together to facilitate the fast passage of containers from the heating chamber to the cooling apparatus. Subsequent to that passage to the cooling apparatus, the containers then proceed around each adjacent lower track  30  before encountering another ramp  48  downwardly to the next subjacent track, thus maximizing their exposure to cooling sprays. As the containers are moved around the circular tracks between the lowermost portion of the heating chamber housing and the lowermost circular circular track, the application of the cooling fluids spray will cool the containers  26 , suitably to the final temperature required for the process. 
   The lowermost circular track  30  has its opening and downwardly extending ramp positioned, in this illustrative embodiment, on the side of the apparatus opposite that of the introduction conveyor  22 . An exit conveyor  60 , conveniently of similar structure to the introduction conveyor  22 , is provided and likewise synchronized with the movement of the transport apparatus and the introduction conveyor. This exit conveyor  60  carries the containers to a conventional stacking apparatus, which preferably turns the containers onto their ends for removal for further processing and subsequent distribution. 
   As shown in  FIG. 1 , the heating chamber housing of this embodiment is generally of the shape of a right circular cylinder, and preferably is made up of two axially adjacent sections  14  and  16 . Preferably the upper cylindrical section  14  engages the circular top portion  13  of the heating chamber with a resilient steam seal  15 , suitably formed from a synthetic polymer. Similarly, lower cylindrical section  16  preferably engages the upper section  14  with a similar resilient steam seal  17 . These sections are supported for axial movement by linear actuators  54  and  56 , respectively, which suitably may be pneumatic or hydraulic cylinders. As shown in the broken lines on  FIG. 1 , actuation of these cylinders  54  and  56  permits the selective axial displacement of the cylindrical sections  14  and  16 . In a first position, with both these segments raised, the heating chamber is completely enclosed by these two sections. In a second position, with the actuating cylinders extended, the heating chamber sections are selectively lowered, either together, or with the lower section being lowered individually, to expose at least a portion of the heating chamber for maintenance and cleaning, as desired. 
   While other embodiments of this invention will be readily apparent to those skilled in the art, the foregoing is intended to be descriptive only of the principles of the invention and is not intended to the limitative thereof. Accordingly, the scope of this invention is to be defined set forth below.