Abstract:
A vacuum packaging appliance for sealing items in a plastic bag is disclosed. The appliance comprises a lid adapted to define a vacuum chamber when it is moved to a closed position relative to a trough in the base of the device. The trough in the lower portion of the device contains a heat-sealing element used to seal the contents of the bag once the vacuum packaging is complete. In another embodiment, the heat-sealing element is mounted on the lid of the device and comes into contact with the vacuum bag when the lid is in a closed position. The placement of the heat-sealing element minimizes wasted bag material as the heat seal is placed closer to the end of the bag itself

Description:
REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 60/492,090 entitled VACUUM SEALING DEVICE WITH INTEGRATED SEALING ELEMENT(S) AND EVACUATION CHAMBER, by Landen Higer and Charles W. Albritton, and filed on Jul. 31, 2003, which is incorporated herein by reference for all purposes. 
     
    
     BACKGROUND  
       [0002]     Vacuum sealing systems are used to evacuate a container of air and fluid. Vacuum sealing has advantages such as compression of items for easier handling and storage or removal of contaminants such as oxygen or other gases, fluids, or air-borne or fluid-borne particles from the vicinity of items that can be adversely effected by the contaminants. A vacuum sealing apparatus is described in Applicant&#39;s U.S. Pat. No. 4,941,310 by inventor Hanns J. Kristen dated Jul. 17, 1990, which is incorporated herein by reference. The apparatus is for vacuum sealing bags of the type disclosed in Applicant&#39;s U.S. Pat. No. 4,756,422 (referred to hereinafter as the &#39;422 patent) by inventor Hanns J. Kristen dated Jul. 12, 1988, which is incorporated herein by reference. Container material for making vacuum sealing bags may be in the form of a roll of continuously bonded plastic as described in the &#39;422 patent. The apparatus includes a hood adapted to define a vacuum chamber when it is moved to a closed position on a support surface. A sealing element, outside the vacuum chamber, is adapted to seal the bag. An alternative sealing element is described in Applicant&#39;s U.S. Pat. No. 6,058,998 by inventor Hanns J. Kristen dated May 9, 2000, which is incorporated herein by reference.  
         [0003]      FIG. 1  depicts an exemplary prior art vacuum sealing bag  10 - 1  before evacuation and the vacuum sealing bag  10 - 2  after evacuation. An item  12  and contaminants  14  are inside the bag  10 - 1 . Contaminants  14  may include moisture, atmospheric gases beyond a certain pressure, and other gas, liquid, or particulate impurities. The contaminants may be spread throughout the interior of the bag  10 - 1  and may be on the item  12 . The bag  10 - 1  is evacuated through the opening  16 . After evacuation, the item  12  remains inside the bag  10 - 2 , but a large proportion of the contaminants  14  have been evacuated. Nevertheless, some contaminants  18  may remain near the seal zone  20 . In addition, a portion  22  of the bag material may be wasted.  
         [0004]     It would be advantageous to provide an apparatus that can reduce the contaminants that are trapped near the seal zone of a vacuum sealing bag or to reduce the amount of wasted bag material. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  depicts a prior art vacuum sealing container before and after evacuation.  
         [0006]      FIG. 2  depicts a conceptual isometric view of an exemplary vacuum sealing system according to an embodiment of the invention.  
         [0007]      FIG. 3  depicts a flowchart of an exemplary method for vacuum sealing using the system of  FIG. 2 .  
         [0008]      FIG. 4  depicts an exemplary vacuum sealing container before and after evacuation using the method of  FIG. 3 .  
         [0009]      FIG. 5  depicts a flowchart of an exemplary method for vacuum sealing according to an embodiment of the invention.  
         [0010]      FIG. 6  depicts an isometric view of an exemplary vacuum sealing apparatus according to an embodiment of the invention.  
         [0011]      FIG. 7  depicts a flowchart of an exemplary method for vacuum sealing using the apparatus of  FIG. 6 .  
         [0012]      FIG. 8  depicts a cross-sectional view of an exemplary trough with integrated sealing element according to an embodiment of the invention.  
         [0013]      FIG. 9  depicts an isometric view of an exemplary vacuum chamber lid with integrated power coupling according to an embodiment of the invention.  
         [0014]      FIG. 10  depicts a cross-sectional view of an exemplary vacuum chamber lid with integrated sealing element and trough according to an embodiment of the invention.  
         [0015]      FIG. 11  depicts a cross-sectional view of an exemplary vacuum chamber lid and trough with integrated sealing element according to an embodiment of the invention.  
         [0016]      FIG. 12  depicts a stylized prior art system for sealing a vacuum bag with or without evacuating the bag.  
         [0017]      FIG. 13  depicts a stylized system, according to an embodiment of the invention, for sealing a vacuum bag with or without evacuating the bag. 
     
    
     DETAILED DESCRIPTION  
       [0018]     The descriptions below are provided for illustrative purposes only. Unless specifically stated, the following descriptions should not be limited to the specific structure or instances taught in the application. Moreover, the figures are for exemplary purposes only. The figures generally illustrate but one of many alternatives.  
         [0019]     The following discussion, with reference to  FIGS. 2-5 , provides a conceptual overview of an embodiment of the invention. Later, after presentation of this overview, other embodiments are discussed with reference to the remaining figures.  
         [0020]      FIG. 2  depicts a conceptual isometric view of an exemplary vacuum sealing system according to an embodiment of the invention. The depicted system is but one of many alternatives. The system includes a vacuum sealing device  30  and a vacuum sealable container  32 . Inside the vacuum sealing device  30  is a vacuum chamber (not shown) that includes a hermetic inlet  46  configured to receive at least a portion  34  of the vacuum sealable container  32 . The vacuum chamber is configured for evacuation by a vacuum source (not shown) that is in fluidic communication with the vacuum chamber during an evacuation procedure. The evacuation procedure entails substantially evacuating the vacuum chamber. The system may include a power conduit (not shown) that is configured to provide power from a power source (not shown) to drive the vacuum source during the evacuation procedure.  
         [0021]     The vacuum sealing device  30  includes an upper housing member  36 , a lower housing member  38 , an upper hermetic member  40 , a lower hermetic member  42 , and a sealing element  44 . The upper hermetic member  40  is connected to the upper housing member  36  and the lower hermetic member  42  is connected to the lower housing member  38 . When the upper housing member  36  abuts the lower housing member  38 , the upper hermetic member  40  and lower hermetic member  42  form a barrier, which substantially prevents air from entering the vacuum chamber of the vacuum sealing device  30 . Pressing the upper housing member  36  and lower housing member  38  together may help to form a better barrier. The inner surfaces of the housing, which includes the upper housing member  36  and the lower housing member  38 , defines the vacuum chamber therein.  
         [0022]     The sealing element  44 , which may be a heat sealing element, is located within the vacuum chamber. The sealing element  44  is configured to secure a first part of the portion  34  of the vacuum sealable container to a second part of the vacuum sealable container when the portion  34  is proximate to the sealing element  44  at least during a time period in which the vacuum chamber is substantially evacuated during the evacuation procedure. Conceptually, the sealed parts of the vacuum sealable container are the sides of the container, which are stuck together to form a seal. The system may include a power conduit (not shown) that is configured to provide power from a power source (not shown) to drive the sealing element  44  at least during the time period in which the vacuum chamber is substantially evacuated. The sealing element  44  may complete the seal during that time period. The sealing element  44  may be energized in response to an evacuation detection mechanism determining that the vacuum chamber has been at least partially evacuated. Evacuation detection mechanisms are well-known in the art of vacuum packaging so a detailed description of such mechanisms is omitted herein.  
         [0023]     The upper housing member  36  may serve as a lid for the vacuum sealing device  30 . The upper housing member  36  may be detachable or affixed to the lower housing  34 . If the upper housing member  36  is affixed to the lower housing  34 , it may be affixed by a hinge. Assuming the upper housing member  36  can be opened, when the upper housing member  36  is open, the vacuum sealable container may be easier to place than when the upper housing member  36  is closed. When the upper housing member  36  is closed, the upper hermetic member  40  contacts the lower hermetic member  42 , thereby forming a barrier to prevent air from entering the vacuum chamber via the hermetic inlet  46  through which the vacuum sealable container  32  extends.  
         [0024]      FIG. 3  depicts a flowchart of an exemplary method for vacuum sealing using a vacuum sealing system, such as the system depicted in  FIG. 2 . The depicted method is but one of many alternatives. The flowchart begins at block  50  with placing a vacuum sealable container, that contains contaminants, in a position such that an open end of the vacuum sealable container is in fluidic communication with a vacuum chamber. The flowchart continues at optional block  52  with applying pressure to an upper housing of the vacuum chamber to bring an upper and lower hermetic member firmly together, thereby ensuring the vacuum chamber is hermetically sealed prior to evacuating the vacuum chamber. The flowchart continues at block  54  with evacuating the vacuum chamber such that at least some of the contaminants are evacuated out of the vacuum sealable container. The flowchart continues at block  56  with activating a sealing element located in the vacuum chamber, wherein the activated sealing element causes at least a portion of the vacuum sealable container to seal. The flowchart continues at optional block  58  with releasing the pressure after the activated sealing element causes at least a portion of the vacuum sealable container to seal. The flowchart ends at optional block  60  with removing the vacuum sealable container from the vacuum chamber.  
         [0025]      FIG. 4  depicts an exemplary vacuum sealing container  70 - 1  before evacuation and the vacuum sealing container  70 - 2  after evacuation using the method just described with reference to  FIG. 3 . An item  72  and contaminants  74  are inside the container  70 - 1 . Contaminants  74  may include moisture, atmospheric gases beyond a certain pressure, and other gas, liquid, or particulate impurities. The contaminants  74  may be spread throughout the interior of the container  70 - 1  and may be on the item  72 . The container  70 - 1  is evacuated through the opening  76 . After evacuation, the item  72  remains inside the container  70 - 2 , but a large proportion of the contaminants  74  have been evacuated. There is little or no contamination near the seal zone  78  because the seal was made inside the vacuum chamber. Moreover, only a small portion  80  of the container material may be wasted because the seal was made close to the opening  76 . In fact, in an embodiment, the portion  80  may not exist (e.g., the seal zone  78  extends to the end of the container).  
         [0026]      FIG. 5  depicts a flowchart of an exemplary method for vacuum sealing according to an embodiment of the invention. The flowchart starts at block  90  with at least partially evacuating an evacuatable chamber. The flowchart continues at block  92  with determining that the evacuatable chamber is at least partially evacuated. The flowchart continues at optional block  94  with energizing the sealing element in response to determining that the evacuatable chamber is at least partially evacuated. The flowchart ends at block  96  with sealing a portion of a container that extends into the evacuatable chamber.  
         [0027]     As previously mentioned, the description with reference to  FIGS. 2-5  provides a conceptual overview of the invention. However, the invention is not simply a more complex version of the embodiments described with reference to  FIGS. 2-5 . The invention is limited only by the claims.  
         [0028]      FIG. 6  depicts an isometric view of an exemplary vacuum sealing apparatus  100  according to an embodiment of the invention. The illustrated apparatus  100  is but one of many alternatives. For example, apparatuses suitable to be adapted for use according to an embodiment of the invention are also disclosed in U.S. Pat. No. 4,941,310 and co-pending patent application 60/450,295 filed on Feb. 27, 2003 by inventor Alexandre Baptista, which are incorporated herein by reference. Another apparatus suitable to be adapted for use according to an embodiment of the invention is a portable vacuum sealing apparatus with an evacuation chamber in a hand-held housing. Making use of the portable vacuum sealing apparatus may include clamping the hand-held housing over the opening of a vacuum sealable container, then evacuating the evacuation chamber. Another apparatus suitable to be adapted for use according to an embodiment of the invention is a vacuum sealing apparatus with a side-opening housing. The housing may have a narrow profile that is lowered across the opening of a vacuum sealable container prior to vacuum sealing the container. Another apparatus suitable to be adapted for use according to an embodiment of the invention is a lidless vacuum sealing apparatus, such as described in the co-pending patent application bearing the attorney docket number 37469-8023-001, which is incorporated herein by reference for all purposes. The apparatuses described are for exemplary purposes only. One who is skilled in the art should be able to adapt other vacuum sealing systems for use according to an embodiment of the invention.  
         [0029]     As depicted in  FIG. 6 , the apparatus  100  includes an upper housing  102  and a lower housing  104 , which are connected to one another by a hinge  105 . The upper housing  102  and lower housing  104  may be made of, for example, molded plastic, ceramic, metal, or some other material. The upper housing  102  and lower housing  104  may be referred to collectively as a housing. The hinge  105  may be a mechanism that serves to pivotally mount the upper housing  102  on the lower housing  104 , such that the upper housing  102  is moveable to a closed position. For example, the upper housing  102  may be pivotally mounted on the lower housing  104  by a pair of longitudinally spaced pins. The hinge  105  may also include a torsion spring mounted on each pin to normally bias the upper housing  102  in an open position. It should be noted that the upper housing  102  and lower housing  104  need not be connected by a hinge and, indeed, need not be connected at all (e.g., the upper housing could be a lid that is separable from the lower housing). Alternatively, the upper housing could be fixed in place above the lower housing.  
         [0030]     The upper housing  102  includes a first evacuation module member  106 , a gasket  108 , an evacuation port  110 , a pressure profile  111 , and two contact points  112 . The lower housing  104  includes a second evacuation module member  114 , a heating element  116 , and a gasket  118 . Prior to carrying out an evacuation procedure to evacuate contaminants, such as air, from a container (not shown) and then seal the container, an operator, such as a human being or robotic mechanism, closes the upper housing  102  onto the lower housing  104 . When closed, the first evacuation module member  106  fits together with the second evacuation module member  114  such that a vacuum chamber is defined by the inner surfaces of the evacuation module members.  
         [0031]     Since the first evacuation module member  106 , in the example of  FIG. 6 , fits over the second evacuation module member  114 , the first evacuation module member  106  may be referred to as a lid, a cap, or a cover. It should be noted that the first evacuation module member  106  could, in alternate embodiments, be slid over the second evacuation module member  114 , or screwed on, or fastened with a clamp or other securing device. Moreover, the first evacuation module  106  member could be fixed in place, capping the second evacuation module member  114 , or pivotally mounted on the second evacuation module member  114 . Since the second evacuation module  114 , in the example of  FIG. 6 , defines a volumetric depression, the second evacuation module  114  may be referred to as a trough, a cavity, or a trench. The volumetric depression may function to collect liquids and powder particles that are exhausted from the container to prevent their ingress into a vacuum pump. The first and second evacuation module members may be made of any gas impermeable material, including molded plastic, ceramic, metal, or some other material.  
         [0032]     When the evacuation module members are fit together to form the vacuum chamber, the gasket  108  and the gasket  118  contact one another, forming a hermetic seal between the evacuation module members. In this way, the evacuation module members may not actually contact one another while fit together to form the vacuum chamber. The hermetic seal is a barrier that prevents gas or other contaminants from entering the vacuum chamber during an evacuation procedure. The gaskets may be formed of an elastomeric material. However, in an embodiment, the gaskets are formed of different materials and the contact surface of one or both gaskets may be rigid. For example, in an alternative, the gasket  108  is formed of an elastomeric material while the gasket  118  is formed of a rigid material. As depicted in  FIG. 6 , the gaskets  108  and  118  extend completely around the periphery of the vacuum chamber. While the gaskets  108  and  118  in the example of  FIG. 6  are approximately elliptical in shape, in other embodiments, the gaskets  108  and  118  may be rectangular, polygonal, or of some other shape. It should be noted that the hermetic seal could be formed using a single gasket or more than two gaskets.  
         [0033]     In the example of  FIG. 6 , the evacuation port  110  is formed in the first evacuation module member  106 . An evacuation channel  120  extends from the evacuation port  110  to a vacuum module  122 . The evacuation channel  120  may be a plastic tube. In the example of  FIG. 6 , the evacuation channel  120  extends from the upper housing  102  to the lower housing  104 . The vacuum module  122  is located in the lower housing  104 . The vacuum module may include a vacuum motor (not shown) and a vacuum pump (not shown). The vacuum motor drives the vacuum pump. The vacuum pump communicates with the evacuation channel  120 , which is exposed at the evacuation port  110  to the vacuum chamber, to draw a vacuum therein. The drawing of a vacuum in the chamber may create a differential pressure on opposite sides of the first and second evacuation module members to aid in the static sealing of the vacuum chamber and the container at the hermetic seal, while simultaneously evacuating the container and vacuum chamber. Since evacuation pumps and drive mechanisms are well known in the art, further description of the vacuum module is deemed unnecessary. It should be noted that the evacuation port  110  need not be formed in the first evacuation module member  106 . For example, the evacuation port could be formed in the second evacuation module member  114 , or the evacuation port could be affixed to the end of a hose or tube that extends between the gaskets  108  and  118 . It should further be noted that the vacuum module  122  need not be located in the lower housing  104 . For example, the vacuum module  122 , or a portion thereof, could be located in the upper housing  102  or external to the housing.  
         [0034]     In the example of  FIG. 6 , the heating element  116  is connected to an inner surface of the second evacuation module  1   14 . However, the placement of the heating element  116  need not be as depicted in  FIG. 6 . For example, the heating element.  116  could be affixed to an inner surface of the first evacuation module  106 . Moreover, the heating element  116  could be affixed to an inner surface by an adjustable support, a detachable support, or a flexible support, such as a spring. The heating element  116  includes at least one electrically conductive wire or sealing element that produce heat when a voltage differential is applied across the length of the wire. The heating element may be a low voltage heating element. The heating element  116  may be covered with a material to prevent the heating element  116  from adhering to a container material when the heating element  116  is used to form a heat seal on the container. The heating element  116  could be covered for other reasons, as well, such as safety or to make cleaning easier. The covering material of the heating element  116  could be Teflon® (polytetrafluroethylene) tape or some other relatively heat-resistant material. The heating element  116  or individual wires of the heating element could be wrapped in a material or otherwise coated to protect the heating element  116  from exposure to, for example, liquid. The coating can also serve to protect the apparatus or an operator from the voltage across the heating element  116 .  
         [0035]     In the example of  FIG. 6 , the contact points  112  are positioned in such a way that when the first evacuation module member  106  and the second evacuation module member  114  are fit together to form the vacuum chamber, the contact points  112  contact the heating element  116 . The contact points  112  are part of a power coupling that provides power to the heating element  116 . The contact points  112  may include exposed conductive nodes that conduct electrical current from a power source (not shown) to the heating element  116 , thereby energizing the heating element  116 . Since the contact points  112  are connected to the first evacuation module member  106 , when the evacuation module members are not fit together, the heating element does not receive current through the conductive nodes. Positioning the contact points  112  in this manner results in the equivalent of a switch that disengages the heating element  116  when the evacuation module members are not fit together. This may, for example, prevent an operator from suffering injury. In addition, the contact points  112  may be disengaged from the power source using a switch (not shown) that is open when the evacuation module members are not fit together and is closed when the evacuation module members are fit together, thereby reducing the risk of injury, such as electrical shocks, to an operator.  
         [0036]     The pressure profile  111  may be a longitudinally extending elongated elastomeric member. The pressure profile  111  serves to push a zone of the container into the heating element  116  to assist in forming a seal on the container substantially along the zone. The pressure profile  111  may ensure that adequate pressure is applied on the container over the heating element  116  so that a full seal is made via heat conduction through upper and lower panels of the container to seal heat sealable layers of the container together.  
         [0037]     In operation, an operator, such as a human or robotic mechanism, places a container (not shown) over the heating element  116 . The operator then closes the upper housing  102  onto the lower housing  104 . This has the effect of fitting the first evacuation module member  106  to the second evacuation module member  114  to form the vacuum chamber. The container may extend between the gaskets  108  and  118  through what may be referred to as a hermetic ingress, which is represented in  FIG. 6  by arrows  124 . The hermetic ingress is so named because the gaskets  108  and  118  form a barrier between the container and the gasket  108  and between the container and the gasket  118  that substantially block the amount of contaminants, such as air, that pass into the vacuum chamber from ambient while the container is positioned between the gaskets  108  and  118 . While so positioned, the container may be in fluidic communication with the vacuum chamber such that if the vacuum chamber is evacuated, the container is similarly evacuated.  
         [0038]     As previously indicated, the power coupling engages the heating element  116  through the contacts  112  that contact the heating element  116 . In an embodiment, the power coupling engages the heating element  116  for the entire period of time during which the vacuum chamber is defined by the inner surfaces of the first and second evacuation module members. However, in an alternative, the power coupling need not engage the heating element  116  for the entire period. For example, the power coupling could be set to engage the heating element  116  only when a switch is closed, when a button is pressed, or in response to some other stimulus.  
         [0039]     As previously indicated, the evacuation channel  120  is coupled to the vacuum module  122 . The vacuum module  122  evacuates the vacuum chamber of at least some contaminants through the evacuation channel  120  for at least a period of time during which the vacuum chamber is defined by the inner surfaces of the first and second evacuation module members. This evacuation procedure may begin in response to the first and second evacuation module members being fit together. Alternatively, the evacuation procedure may begin in response to pressure on the upper housing  102  that activates the vacuum module  122  or in response to some other stimulus, such as activating a button, switch, or knob that activates the vacuum module  122 . The evacuation procedure may continue until a vacuum detector (not shown), such as a pressure sensor, determines that the vacuum chamber is sufficiently evacuated. Alternatively, the evacuation procedure may continue until some other stimulus, such as the end of a predetermined or determinable period of time, occurs.  
         [0040]     When the vacuum chamber has been at least partially evacuated, the heating element  116  is energized by power received through the power coupling for at least a period of time during which the vacuum chamber is defined by the inner surfaces of the evacuation module members. The heating element  116  should be energized while the vacuum chamber is defined because if the vacuum chamber integrity is compromised, such as by unfitting the evacuation module members, the integrity of the evacuated container may be adversely effected. The heating element  116  may be energized for a predetermined period of time, such as five seconds, or for a period of time that is determined according to a plurality of factors, such as the initial temperature of the heating element  116  or the presence of liquid or other substance within the vacuum chamber. Moreover, the heating element  116  could be energized at any time by an operator, if desired. For example, an operator may wish to seal a container that has not been evacuated at all.  
         [0041]      FIG. 7  depicts a flowchart of an exemplary method for vacuum sealing using the apparatus of  FIG. 6 . The flowchart starts at block  130  with defining a vacuum chamber by fitting together first and second evacuation module members. The flowchart continues at block  132  with inserting a container at least partially into the vacuum chamber. It should be noted that, as described previously with reference to  FIG. 6 , inserting a container may involve positioning a container and then closing an upper housing. When the upper housing is closed, the vacuum chamber is defined. For this reason, the block  132  may describe an action that begins prior to the action described in block  130 , but the actions end at approximately the same time. The flowchart continues at optional block  134  with pushing a zone of the container onto the heating element. The flowchart continues at block  136  with evacuating the vacuum chamber of at least some contaminants. The flowchart continues at block  138  with energizing a heating element located within the vacuum chamber. The flowchart ends at block  140  with sealing the container using heat from the heating element. If the act described in optional block  134  was executed, the act of sealing the container (block  140 ) includes sealing the container substantially along the zone.  
         [0042]     The techniques described with reference to  FIGS. 6 and 7  allow for improvements over the prior art. For example, the seal on a container is closer to the opening because the sealing element is located inside the vacuum chamber. This results in the consumption of less container material each time a container is sealed, especially when a container is openend and resealed more than once. Moreover, the seal may be better because the seal is made inside the vacuum chamber instead of outside the hermetic seal. Contaminants may be more likely to be trapped just behind the hermetic seal and may be located between the upper and lower panels of the container at the seal zone, thereby reducing the quality of the seal.  
         [0043]      FIGS. 8-10  depict alternative embodiments of the invention. These figures are intended for exemplary purposes only and generally illustrate but one of many alternatives.  
         [0044]      FIG. 8  depicts a cross-sectional view of an exemplary trough with integrated sealing element  150  (referred to hereinafter as the integrated trough  150 ) according to an embodiment of the invention. The integrated trough  150  includes a trough  152 , a gasket  154 , a heat sealing element  156 , a support member  158 , and a removable drip tray  159 . The trough  152  defines a volumetric depression that makes up a portion of an evacuatable chamber when a lid (not shown) is fitted over the trough  152 . The gasket  154  is used to form a hermetic seal around a perimeter of the evacuatable chamber when the lid is placed over the gasket  154 . The heat sealing element  156  is connected to the trough  152  by the support member  158 . The support member supports the heat sealing element  156  at at least one point along the length of the evacuatable chamber such that the sealing element extends along at least a portion of the trough  152 . The support member  158  may be, for example, a sequence of studs along the length of the evacuatable chamber, or an elongated baffold that extends the length of the evacuatable chamber. The heat sealing element  156  is enclosed within the evacuation chamber when the integrated trough  150  is operationally configured for use in a vacuum packaging system. The removable drip tray  159  may be suspended on a flange connected to the stud  158  or some other portion of the trough  152 .  
         [0045]     In operation, a container (not shown) is placed over the gasket  154  arid across the heat sealing element  156 . When the container is evacuated in an evacuation procedure, liquid or particulate contaminants may be caught in the removable drip tray  159 . The sealing element  156  then seals the container. The removable drip tray  159  may be conveniently removed for cleaning. It should be noted that the removable drip tray  159  is one way to implement the functionality of a removable trough. The removable drip tray implementation could cost less than a removable trough with integrated heating element. Alternatively, the removable drip tray could make providing power to the heating element easier, such as by providing a power coupling by wiring through the surface of the trough into the heating element.  
         [0046]     An alternative technique for providing power to the sealing element is described with reference to  FIG. 9 .  FIG. 9  depicts an isometric view of an exemplary vacuum chamber lid with integrated power coupling  160  (referred to hereinafter as the integrated lid  160 ) according to an embodiment of the invention. The integrated lid  160  includes a lid  162 , a gasket  164 , and a “vampire wing” power coupling  166 . The integrated lid  160  could be used with, for example, the integrated trough  160  ( FIG. 8 ). The lid  162  may fit over a trough to define an evacuatable chamber and the gasket  164  may form part of a hermetic seal around a perimeter of the evacuatable chamber. The “vampire wing” power coupling  166  is configured for coupling at or near the ends of a sealing element, such as a heating wire, such that a current flows through the sealing element. The “vampire wings” may be associated with respective positive and negative poles. Current may or may not flow through the sealing element when the “vampire wing” power coupling  166  is engaged. For example, there may be a switch that must be closed in order for the current to flow. The switch may be closed when the “vampire wing” power coupling  166  is engaged, or the switch may be closed in response to some other stimulus, such as substantial evacuation of the evacuation chamber.  
         [0047]      FIG. 10  depicts a cross-sectional view of an exemplary vacuum chamber lid with integrated sealing element and trough according to an embodiment of the invention.  FIG. 10  includes a lid  170 , a trough  172 , a gasket  174 , a heat sealing element  176 , a gasket  178 , a support member  180 , and a pressure profile  182 . The lid  170  is for covering the trough  172 . The trough  172  defines a volumetric depression and the lid  170  and trough  172  together define an evacuatable chamber that includes the volumetric depression when the lid  170  and trough  172  are operationally configured in a vacuum packaging system. Operationally configuring the lid  170  and trough  172  may include fitting the lid  170  and trough  172  together such that the gasket  174  and the gasket  178  form a hermetic inlet  184  and the heat sealing element  176 , which is connected to the lid  170 , rests on the pressure profile  182 . The pressure profile  182  is connected to the trough  172  by the support member  180 . The heat sealing element  176  may receive power through a power conduit (not shown) that extends through the lid  170 .  
         [0048]     In operation, a portion of a heat sealable bag that is within the evacuatable chamber and proximate to the heating sealing element  176  is sealed by the heat sealing element  176 . For example, the heat sealable bag could be positioned between the heat sealing element  176  and the pressure profile  182  when the heat sealing element  176  is energized, thereby forming a seal on the heat sealable bag.  
         [0049]      FIG. 11  depicts a cross-sectional view of an exemplary lid  190  and trough  192  according to an embodiment of the invention. The lid  190  includes a gasket  194 . The trough  192  includes a gasket  196 , a sealing element  198 , a support member  200 , baffolding  202 , a power conduit  204 , and a barrier wall  206 . A hermetic inlet is represented by the arrow  208 .  
         [0050]     When the lid  190  is engaged with the trough  192 , the gasket  194  forms a hermetic seal with the gasket  196 . In addition, the gasket  194  acts as a pressure profile, much like the pressure profile  182  ( FIG. 10 ), that presses a vacuum sealable container (not shown) onto the sealing element  198 . In the example of  FIG. 11 , the gasket  194  is larger than the respective gasket  196  and sealing element  200 . In an embodiment, the gasket  194  may have a width dimension that extends from an outer edge of the gasket  196  to the inner edge of the sealing element  200 . In another embodiment, the gasket  194  may extend up to but not over the baffolding  202 . In another embodiment, the gasket  194  may extend over the baffolding  202 . In fact, the gasket  194  could be of any practicable width so long as it performs its function as an upper part of a hermetic seal when the lid  190  and trough  192  are engaged. The baffolding  202  helps to prevent intake of fluid from the vacuum sealable container into the trough  192 . A drip tray (not shown) could also be used to catch fluids or other matter that enters the trough, either in conjunction with the baffolding  202  or in lieu of the baffolding  202 . In the example of  FIG. 11 , the sealing element  198  receives power via a power conduit  204 . The barrier wall  206  segregates the power conduit  204  from the vacuum chamber that is defined by inner walls of the lid  190  and trough  192  when the lid and trough are engaged. The barrier wall  204  is not necessary if power is supplied to the sealing element in some other manner, such as those described with reference to  FIGS. 8-10 , above. Alternatively, a power conduit may extend through the support member  200  without becoming exposed as depicted in  FIG. 11 .  
         [0051]      FIG. 12  depicts a stylized prior art system  210  for sealing a vacuum bag  212  with or without evacuating the bag. The system  210  includes a bag sealer  214 , an air barrier  216 , and part of a vacuum chamber  218 . In this system, the bag is normally sealed at a distance x+1 from the end of the bag that opens into the vacuum chamber  218 . When the trough is evacuated, the bag sealer  214  may seal the bag automatically. For example, the bag sealer  214  may be energized when a vacuum exists in the vacuum chamber  218 . Notably, if the bag opening extends past the bag sealer  214 , but not past the air barrier  216 , then when the vacuum chamber  218  is evacuated, the bag can be sealed automatically, as well. This technique consumes less than a length x of bag material, but does not allow for a vacuum seal. The technique is particularly useful when a partial bag, with two open ends, is to be sealed at one of the open ends, filled with materials that are to be vacuum packaged, and vacuum sealed. Since the partial bag need not extend past the air barrier  216 , the vacuum chamber  218  may be evacuated normally and the partial bag automatically sealed when the vacuum chamber  218  has a requisite pressure.  
         [0052]      FIG. 13  depicts a stylized system  220 , according to an embodiment of the invention, for sealing a vacuum bag  222  with or without evacuating the bag. The system  220  includes a bag sealer  224 , an air barrier  226 , and a part of a vacuum chamber  228 . In this system, if the bag  222  extends past the bag sealer  224 , the bag invariably extends past the air barrier  226  into the vacuum chamber  228  because the bag sealer  224  is located inside the vacuum chamber  228 . This may be an issue when, for example, a partial bag is cut from a roll of material and has two open ends. If one end of a partial bag is inserted into the vacuum chamber  228 , the vacuum chamber  228  may not be able to evacuate, since air is drawn through one end of the partial bag into the vacuum chamber  228 . According to the usual technique, only a bag (not a partial bag) can be sealed in this manner, since the bag can be evacuated simultaneously with the vacuum chamber  228 , thereby allowing the vacuum chamber  228  to be evacuated. To make the first seal on a partial bag, a technique that avoids evacuating the vacuum chamber  228  or enables evacuation of the vacuum chamber  228  even though a partial bag is inserted into the vacuum chamber  228 . Such techniques may include, but are not limited to, applying sufficient pressure to the air barrier  226  that substantially less air passes from the partial bag into the vacuum chamber  228  than usual, enclosing the partial bag in a bladder that is evacuated simultaneously with the vacuum chamber  228 , providing a latch that can close over a portion of the partial bag such that a significant air barrier is formed at the location of the latch due to pressure on the sides of the bag, or providing a seal-only mode of operation wherein the system does not attempt to evacuate the vacuum chamber  228  prior to energizing the bag sealer  224 .  
         [0053]     Although it is presented here that the present invention is designed primarily for use in food preservation, it is contemplated that the improved vacuum sealing would allow for use in other types of preservation systems. For example, the use of toxic dessicants for the shipment of electronic components could be eliminated. The invention could be applied to medical as well as pharmaceutical use. The scope of the invention is not to be restricted by the above descriptions which are provided for illustrative and enablement purposes, but rather should be defined by the claims listed below.