Vacuum sealing system, apparatus, and method

Abstract

A vacuum sealing system includes a vacuum pump, a lower tool to hold one or more trays carrying product, an upper tool to seal a plastic film onto the one or more trays, the upper tool including at least one seal plate with a seal plate cavity and a vacuum clamp, the system also including a controller to control the vacuum pump, the lower tool, and the upper tool.

What is claimed is: 
     
         1 . A vacuum sealing system, comprising:
 a vacuum pump;   a lower tool to hold one or more trays carrying product;   an upper tool to seal a plastic film onto the one or more trays, the upper tool comprising:
 at least one seal plate, each seal plate comprising:
 a seal plate cavity; and 
 a plurality of first holes to allow air to be drawn out of the seal plate cavity with the vacuum pump to draw the plastic film into the seal plate cavity, and to allow the seal plate cavity to be vented to equalize an air pressure therein with ambient air pressure; 
 
 a vacuum clamp disposed around the seal plate, the vacuum clamp comprising:
 a groove to receive the plastic film; and 
 a plurality of second holes to allow air to be drawn out of the groove with the vacuum pump and thereby hold the plastic film in the groove; and 
 
   a controller to control the vacuum pump, the lower tool, and the upper tool.   
     
     
         2 . The vacuum sealing system of  claim 1 , wherein the controller comprises:
 a user interface to receive a user input to control the vacuum pump, the lower tool, and the upper tool; and   a memory device to store one or more timing charts, each timing chart comprising instructions to control the vacuum pump, the lower tool, and the upper tool.   
     
     
         3 . The vacuum sealing system of  claim 1 , wherein the groove comprises a square cross-section. 
     
     
         4 . The vacuum sealing system of  claim 1 , further comprising a set of blades to cut the plastic film. 
     
     
         5 . The vacuum sealing system of  claim 1 , wherein the at least one seal plate further comprises a heating element to heat the plastic film to a predetermined temperature. 
     
     
         6 . The vacuum sealing system of  claim 5 , wherein the at least one seal plate further comprises a temperature probe to determine a temperature of the at least one seal plate. 
     
     
         7 . The vacuum sealing system of  claim 1 , further comprising:
 a set of grippers to move one or more trays from an entry conveyor to between the upper tool and lower tool, and to move one or more trays from between the upper tool and lower tool and onto an exit conveyor.   
     
     
         8 . A vacuum sealing apparatus, comprising:
 at least one seal plate, each seal plate comprising:
 a seal plate cavity; and 
 a plurality of first holes to allow air to be drawn out of the seal plate cavity to draw a plastic film into the seal plate cavity, and to allow the seal plate cavity to be vented to equalize an air pressure therein with ambient air pressure; 
   a vacuum clamp disposed around the seal plate, the vacuum clamp comprising:
 a groove to receive the plastic film; and 
 a plurality of second holes to allow air to be drawn out of the groove and thereby hold the plastic film in the groove. 
   
     
     
         9 . The vacuum sealing apparatus of  claim 8 , wherein the at least one seal plate further comprises a heating element to heat the plastic film to a predetermined temperature. 
     
     
         10 . The vacuum sealing system of  claim 9 , wherein the at least one seal plate further comprises a temperature probe to determine a temperature of the at least one seal plate. 
     
     
         11 . A method of vacuum sealing, the method comprising:
 moving one or more trays holding product into a packaging portion comprising an upper tool and a lower tool;   forming a first vacuum in the upper tool to hold a plastic film;   forming a second vacuum on a first side of the plastic film to draw the plastic film into one or more seal plate cavities over the one or more trays;   strengthening the second vacuum to form a third vacuum on the first side of the plastic film;   forming a fourth vacuum on a second side of the plastic film after forming the third vacuum, the second side of the plastic film being opposite from the first side of the plastic film; and   releasing the third and fourth vacuums to force the plastic film onto the one or more trays.   
     
     
         12 . The method of  claim 11 , further comprising:
 releasing the fourth vacuum after the third vacuum to generate a pressure differential between the plastic film and the tray carrying the product.   
     
     
         13 . The method of  claim 11 , further comprising:
 heating the plastic film to a predetermined temperature prior to forming the second vacuum.   
     
     
         14 . The method of  claim 11 , further comprising increasing air pressure against the first side of the plastic film after releasing the third vacuum. 
     
     
         15 . The method of  claim 11 , wherein the one or more trays are moved into the packaging portion simultaneously as the first vacuum is formed. 
     
     
         16 . The method of  claim 15 , further comprising:
 moving the one or more trays out of the packaging portion after forcing the plastic film onto the one or more trays; and   simultaneously moving one or more additional trays carrying product into the packaging portion.   
     
     
         17 . A non-transitory computer-readable recording medium to contain computer-readable codes as a program to execute the method of  claim 11 . 
     
     
         18 . A vacuum sealing system comprising:
 a lower tool to receive at least one tray carrying a product; and   an upper tool including a seal plate cavity with a plurality of first holes therein to receive a vacuum to draw a plastic film into the seal plate cavity and a groove surrounding an outer perimeter of the seal plate cavity and including a plurality of second holes therein to receive a vacuum to draw the plastic film into the groove;   wherein at least one of the lower tool and the upper tool moves toward the other tool to seal the plastic film to the at least one tray.   
     
     
         19 . The vacuum sealing system of  claim 18 , further comprising:
 a vacuum pump to form a vacuum; and   a controller to control movement of at least one of the upper and lower tools and to control the vacuum pump to create a first and second vacuum to be drawn through the first holes and a third vacuum to be drawn through the second holes.   
     
     
         20 . The vacuum sealing system of  claim 18 , wherein the upper tool further comprises a heating element to heat the plastic film to a predetermined temperature.