Patent Publication Number: US-2006017189-A1

Title: Molding arrangement and method including vacuum assisted ventilation

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      This application claims priority from provisional Ser. No. 60/563,179 filed Apr. 16, 2004, which is incorporated herein by reference. 
    
    
     BACKGROUND AND SUMMARY  
      The present invention relates to an arrangement and method for molding products and, more particularly, to an arrangement and method for molding products with vacuum-assisted evacuation of air from the mold.  
      Certain molding or forming apparatus, such as those used in molding food materials such as ground meat and vegetables, comprise a shaping mold volume with an inlet for receiving a charge of the product to be molded and an escape passage for venting gas such as air from the mold volume while charging the volume with the product. U.S. Pat. No. 3,869,757, which is incorporated by reference, discloses an example of such a molding apparatus.  
      In accordance with an aspect of the present invention, an arrangement for molding products includes a mold defining a volume, the mold including an inlet leading to the volume for receiving product to be molded and an outlet for venting air from the volume, and a vacuum connected to the outlet.  
      In accordance with another aspect of the present invention, a method for molding products includes evacuating air from a mold volume through an outlet of the mold volume with a vacuum, and forcing product to he molded into the mold volume through an inlet of the mold volume.  
      When molding food products, it is desirable to avoid contact of the food products with air to minimize the possibility of contamination. Accordingly, it is desirable to vent gas such as air from a mold volume prior to charging the mold volume with the product.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The features and advantages of the present invention are well understood by reading the following detailed description in conjunction with the drawings in which like numerals indicate similar elements and in which:  
       FIG. 1  is a schematic, partially cross-sectional view of an arrangement for molding products showing a mold member in a molding position;  
       FIG. 2  is a schematic, partially cross-sectional view of an arrangement for molding products showing a mold member in an ejection position; and  
       FIG. 3  is a schematic, partially cross-sectional view of an arrangement for molding products showing a mold member moving from an ejection position to a molding position. 
    
    
     DETAILED DESCRIPTION  
      An arrangement  21  for molding products is seen in  FIGS. 1 and 2  and includes a mold  23  defining a volume  25 . The mold  23  includes an inlet  27  leading to the volume  25  for receiving product such as ground meat or vegetables to be molded and an outlet  31  for venting air from the volume. A vacuum device  33  is connected to the outlet  31 . Though the present invention is described in connection with a preferred embodiment for forming food products into shapes such as patties, it will be appreciated that the present invention has application in a variety of molding applications. An example of a device with which the present invention is adapted to be used is described in U.S. Provisional Application No. 60/563,178, filed Apr. 16, 2004 and incorporated herein by reference.  
      The mold  23  preferably includes a top member  35  and a bottom member  37  and a mold member  39  including a cavity  41  disposed between the top member and the bottom member. The volume  25  is preferably defined by the cavity  41 , the top member  35 , and the bottom member  37 . The mold member  39  is preferably movable relative to the top member  35  and the bottom member  37 . The mold member  39  is preferably movable between a molding position ( FIG. 1 ) in which the cavity  41  is disposed between the top and the bottom member  35  and  37  and an ejection position ( FIG. 2 ) in which the cavity is not disposed between the top and the bottom member. As seen in  FIG. 2 , a punch  43  is preferably provided for removing molded products  29  from the cavity  41  when the mold member  39  is in the ejection position.  
      The inlet  27  and the outlet  31  are preferably in flow communication when the mold member  39  is in the forming position to facilitate venting of any air remaining in the cavity  41 . Flow communication between the inlet  27  and the outlet  31  is preferably substantially blocked when the mold member  39  is in the ejection position.  
      The mold member  39  is preferably in the form of a plate and the cavity  41  is preferably an opening extending through the plate. The inlet  27  and the outlet  31  are preferably both provided in the top member  35 , although the inlet  27  and/or the outlet  31  can, if desired or necessary, be in either the top or the bottom member  35  or  37  or both.  
      The top member  35  is preferably a breather plate forming part of a ram block  45  having a ram  47  and a rain cylinder  49  and, when the mold member  39  is in the molding position, the ram cylinder and the volume  25  communicate through the inlet  27 . A surface of the top member  35  preferably defines a portion of the ram cylinder  49 . The ram  47  forces the product from the cylinder  49  through the inlet  27  and into the volume  25 . The bottom member  37  is preferably part of the ram block  47  or attached to the ram block. The outlet  31  preferably communicates with a ventilation volume  51  to which the vacuum  33  is attached. The arrangement  21  for molding products preferably includes the ram arrangement as well as a source of supply (not shown) of the product to be molded, such as a hopper that grinds meat and delivers it through a conduit under pressure by means such as a screw. The arrangement  21  for molding products may, however, include a ram arrangement that is integral with a hopper, or, if desired or necessary, the ram arrangement may be omitted and the hopper can supply the product to be molded to the mold  23  without an intermediate ram arrangement. The inlet  27  and the outlet  31  are preferably arranged relative to one another such that, when the mold member  39  moves from the ejection position to the molding position, the outlet of the mold volume  25  opens before the inlet of the mold volume as seen in  FIG. 3 . In this way, the vacuum  33  can evacuate air from the mold volume  25  through the outlet  31  before introduction of the product through the inlet begins, which can assist in avoiding contamination of certain food products. Also, the vacuum is believed to assist in causing the product to fill the mold volume  25  and to assist in providing a uniform consistency to the molded product.  
      The outlet  31  is preferably in the form of one or more, preferably a plurality of, outlet openings  53 . Each of the outlet openings  53  is preferably substantially smaller than the inlet  27  so that the tendency will be for only air to enter the outlet openings  53  while the product that is introduced to the mold volume  25  will tend to remain in the mold volume.  
      In a method for molding products according to an embodiment of the present invention, air is evacuated from the outlet  31  of the mold volume  25  with a vacuum  33  and the product is forced into the mold volume through the inlet  27 . When the mold member  39  is moved to the ejection position ( FIG. 2 ) molded products are removed from the cavity  41 , such as by a punch  43 . When returning the mold member  39  to the molding position, the outlet  31  opens and air is evacuated from the mold volume  25  with the vacuum  33  before opening the inlet  27  of the mold volume opens.  
      While this invention has been illustrated and described in accordance with a preferred embodiment, it is recognized that variations and changes may be made therein without departing from the invention as set forth in the claims.