Heat sealing element and control of same
A vacuum packaging appliance for heat sealing items in a vacuum packaging 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. Adjacent to a trough in the lower portion of the device, a heat sealing element is placed in order 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 heat sealing elements are controlled by a controller that allows operator selections of seals and sealing time adjustments based on inputs from a plurality of sensors. The controller is further able to energize one or two of the heating elements based on predetermined conditions. The methods and structures described control both heating and cooling of the heat sealing elements. The vacuum pump exhaust may also be directed below the heat sealing elements in order to cool the elements. The control and placement of the heat sealing elements allows for precise feedback and temperature control of the elements and therefore ensuring proper vacuum sealing of the containers.
This application claims priority to Albritton et al.'s provisional patent application 60/491,876, filed Jul. 31, 2003, entitled HEAT SEALING ELEMENT AND CONTROL OF SAME, the contents of which are incorporated herein by reference.
TECHNICAL FIELDThe invention relates to a vacuum packaging appliance for packaging products and more particularly to heat sealing elements and a heat sealing controller used to seal an evacuated container once it has been processed by the vacuum packaging appliance.
BACKGROUND OF THE INVENTIONPresently, various appliances and methods are used for the purpose of vacuum sealing plastic bags and containers to protect perishables, such as foodstuffs, and other products against oxidation. Conventional commercial appliances and some consumer appliances are generally expensive to manufacture, complex in construction and/or cumbersome to operate. There are also different types of heat sealing mechanisms contained in these prior art devices that have limited success in hermetically sealing the evacuated bags.
One type of conventional vacuum sealing appliances uses a vacuum nozzle that is inserted within a plastic bag for evacuation purposes. Although adaptable for low-volume home use, this type of system is cumbersome to use and normally requires a liquid separator or filter to prevent liquids or powders, retained within the bag, from being drawn into a vacuum pump connected to the nozzle. Further, a heat sealer employed therein must be closely synchronized with the positioning and withdrawal of the vacuum nozzle from the bag. This greatly adds to the cost and complexity of the device itself
U.S. Pat. No. 3,928,938 discloses another type of vacuum sealing appliance that employs a heat sealing mechanism. In this appliance a user places a portion of a bag, containing a product to be packaged, in a first vacuum chamber and extends an open end or neck of the bag into a second vacuum chamber. The first vacuum chamber is then evacuated to expand the neck of the bag to isolate the chambers from each other. Then a vacuum is drawn in the second vacuum chamber to evacuate the bag. Thus, isolation of the two chambers from each other, during evacuation of the second vacuum chamber, is dependent on the physical properties composing the neck of the bag and very close synchronization and calibration of the evacuation and sealing procedures and controls therefor. This complex process in conjunction with the heat sealing mechanism is not reliable.
These prior art appliances described above and others require the use of special bags that must be purchased from the manufacturer. Due to the cost of the vacuum useable bags, it is desirable to conserve the material as much as possible. One problem with the above appliances is that there is a substantial amount of wasted vacuum bag material between the end of the bag and the heat seal as shown in Prior Art
Another problem with prior art vacuum packaging appliances is that the temperature of the heat sealing mechanism is not accurately controlled. This is because the prior art appliances use a simple on/off time switch to excite the heat sealing elements. Under the heat seal control mechanism of the prior art, sealing multiple bags without allowing the heat sealing element to cool results in bags beginning to seal before the vacuum process is complete. This causes ineffective seals and prevents complete evacuation of gas from the bags, that results in expensive packaging bag waste. Further, activating the elements without considering real-time temperature may cause damage to the appliance due to element overheating.
Therefore there exists a need for a vacuum packaging appliance that accurately controls the temperature of the heat sealing elements and optimizes the placement of the heat sealing elements within the appliance.
SUMMARY OF THE INVENTIONThe present invention sets forth several embodiments relating to the position and control of heat sealing elements within a vacuum packaging appliance. 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. A heat sealing element is mounted in close proximity to the trough. 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 adjacent to the trough minimizes wasted bag material as the heat seal is placed closer to the end of the bag itself.
In addition to the positioning of the heat sealing elements, the present invention also includes the controlling of these heat sealing elements. These embodiments provide features such as a heat sealing controller that allows an operator to select a type of heat seal formed on the evacuated container. The heat sealing controller controls the electrical current supplied to the heat sealing element as selected using a control panel that allows the operator to select between 3 types of heat seals. The control panel is operatively connected to the heat sealing element controller. The heat sealing element controller may also suspend heat sealing operations for a predetermined period of time in order to avoid heat seal element overheating. The controller also can adjust the duration of control signals applied to the heat sealing elements based on parameters such as the real-time temperature of the elements and the amount of liquid sensed in the trough while evacuating the container.
The present invention includes a method for controlling a vacuum packaging appliance that comprises the acts of coupling a vacuum packaging receptacle to a vacuum circuit, hermetically separating said vacuum circuit from ambient, operating a vacuum pump to obtain a desired vacuum within said vacuum packaging receptacle, sensing an input related to the control of a heat sealing element, determining an actuation control signal for energizing the heat sealing element as a function of the input, and then applying an actuation control signal to the heat sealing element.
In the embodiments disclosed, the input used to control the heat sealing element may be any one or a combination of inputs such as temperature, type of heat seal selected by an operator, and amount of liquid sensed in a trough. In another embodiment, the heat seal element controller may increase or decrease the current provided to the heat sealing elements to maintain a constant element temperature or maintain the element within a predetermined temperature range. This type of feedback control allows for precise temperature control. In still another embodiment, the controller may send a signal to direct the vacuum pump exhaust under the heat sealing elements in order to cool the elements if the sealing elements have exceeded a predetermined temperature.
In still further embodiments, the heat sealing element provided is comprised of two sealing wires. In order to more accurately control the temperature of the heat sealing elements and operations, one or both wires may be activated. For example when liquids are present a heavy seal is desired so both wires are activated. If the temperature of the elements is already hot, only one wire may be activated for sealing purposes. The heat sealing controller performs the controlling of the elements.
The present invention therefore optimizes the placement and temperature control of the heat sealing elements within a vacuum packaging appliance.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention sets forth several embodiments relating to the position and control of heat sealing elements within a vacuum packaging appliance. The heat sealing element may be mounted on the lid or the base of the appliance. The placement of the heat sealing element within the appliance minimizes wasted bag material, as the heat seal is placed closer to the end of the bag itself The present invention also includes a heat sealing controller that may adjust the amount of current applied to the heat sealing element based on a number of different inputs. It will be understood by those skilled in the art that the description of the methods and structures of the vacuum packaging appliance described below is not intended to be limiting in anyway.
The rotary dial 304 has multiple positions that can control various aspects of the vacuum packaging appliance 100, for example: “Accessory”, 1, 2, 3 and “Seal Only”. However in other embodiments, the rotary dial may have more or fewer settings that can control various aspects of the vacuum packaging appliance 100. When the rotary dial 304 is in the accessory position, the accessory port 312 is activated and accessories (not shown) can be attached to the vacuum packaging appliance 100 either directly or via a vacuum hose. When the rotary dial 304 is in any position other than the accessory position, the accessory port 312 is sealed off and a vacuum is not drawn through the accessory port 312.
Positions 1, 2 and 3 of the rotary dial 304 allow the user to control the duration of the evacuation process and the length of time the heat sealing element is activated. Position 1 may activate the sealing mechanism for a first predetermined period producing a light seal. Position 2 may activate the sealing mechanism for a second predetermined period producing a medium heat seal, and position 3 may activate the sealing mechanism for a third predetermined period resulting in a heavy heat seal. Position 1 would correspond to a fragile content mode, wherein an actuation control signal would have a sealing time period shorter than a normal content mode sealing time period. Thus, the user can select the duration of the sealing process. For example sealing potato chips or fruit may require a fragile or light seal; whereas sealing meat would require a heavy seal. The seal only position allows a user to use the apparatus to operate a sealing mechanism only, without requiring evacuation of a primary evacuation chamber.
Although the apparatus shown in
The cancel button 306 allows a user to cancel a vacuum operation or sealing operation at any time during the operation. The instant seal button 308 allows a user to terminate the evacuation process and begin the sealing process at any time during operation of the vacuum packaging appliance 100. The extended vacuum button 310 allows a user to extend the length of time for which the container (not shown) is evacuated. The accessory port 312 allows a user to connect the apparatus to various containers as described in U.S. Pat. 4,491,310, by Hanns J. Kristen, issued Jul. 17, 1990, and assigned to the same assignee as this patent application, the complete contents of which is incorporated herein by reference.
The indicator light 314 serves to notify a user of the status of the vacuum packaging appliance 100. In the embodiment shown in
The base 104 of the vacuum packaging appliance 100 includes an electromechanical switch 416, positioned on the base such that when the lid 102 is in a closed position, the protrusion 414 is substantially vertically aligned with the electromechanical switch 416. Thus, when the lid 102 is in a closed position and then is further depressed, the protrusion 414 can actuate the electromechanical switch 416 and activate the vacuum packaging appliance 100.
The base 104 of the vacuum packaging appliance 100 shown in
The roll of container material may be a single roll of continuously bonded plastic as described in U.S. Pat. No. RE34,929, by Hanns J. Kristen, issued May 9, 1995 a reissue patent based on U.S. Pat. No. 4,756,422, by Hanns J. Kristen, issued Jul. 12, 1988, assigned to the assignee of the present application, the complete contents of which is incorporated herein by reference. However, in alternate embodiments, the roll of container material 424 may be any convenient material.
The thermal sealing mechanism 433 includes one or more electrically conductive wires that produce heat when a voltage differential is applied across the length of the wire. In the embodiment shown, the electrically conductive wires are covered with a Teflon tape. However, in alternate embodiments, the wires maybe exposed or wrapped in a material. If the sealing mechanism 433 is activated and container material 424 is disposed between the sealing gasket 406 and the sealing mechanism 433, the container material 424 can be hermetically sealed. Although the apparatus 100 is described as including a sealing mechanism 433 that is integrated with the apparatus, in alternate embodiments, the sealing mechanism 433 may be on the base of the device while the electrical contacts are located on the lid. Additionally in alternate embodiments, various other placements of the heat sealing mechanisms 433 may be employed in order to seal the container material 424.
In operation, when the lid 102 is in a closed position and is depressed such that the protrusion 414 actuates the electromechanical switch 416, the vacuum pump or source is activated. Evacuation of the primary evacuation chamber 404 and trough 430 is then performed. When the lid 102 is in a closed position, the gasket 406 surrounding the primary evacuation chamber 408 and the trough 430 are substantially vertically aligned such that a vacuum circuit is obtained or formed.
For cleaning purposes, the trough 430 is removable from the base 104 of the vacuum packaging appliance 100 through the aperture 112 when the door 114 is in an open position. In the embodiment shown in
In operation, a user inserts an open end of a container, such as a flexible bag, into the trough 430 or attaches a container to the accessory port 312. The user then selects a setting on the rotary dial 304, closes the lid 102 and depresses the lid 102 past the closed position to actuate the electromechanical switch 416 with the protrusion 414. The vacuum source 434 will then evacuate the latch chambers 402 to hold the lid 102 relative to the base 104. Once the lid 102 is secured relative to the base 104, the primary evacuation chamber 408 and the trough 430 are evacuated thus evacuating the open container inserted into the appliance 100. When the vacuum strength reaches a predetermined level, the sealing mechanism 433 will be activated to seal the container. The evacuated and sealed container may then be released from the vacuum packaging appliance 100.
The embodiment of
As can be seen from
Also shown in
The opening of the valve 808 is controlled by a signal from a heat sealing element controller that receives a temperature sensor input. The valve 808 is opened by the controller in response to a predetermined temperature of the heat sealing elements being exceeded. For example, if the heat-sealing layer of the vacuum packaging bag melts at 130 degrees, the predetermined temperature may be set at 120 degrees. This ensures that the heat sealing elements 420 stay below a melting temperature, so as to not prematurely produce a heat seal while the vacuum packaging bag is being evacuated. The controller may also open and close the valve 808 as necessary, in order to keep the heat sealing elements at a constant predetermined temperature or within some range below the predetermined temperature. A flowchart of the steps in this process is shown in
A schematic diagram of the control circuitry of the heat sealing element is shown in
The liquid sensor 91 feeds a signal back to the controller 92 indicating the presence or amount of liquid in the trough 430. This is important as the presence of liquids may require higher sealing temperatures of the elements 420, as liquids tend to reduce the effects of the heat sealing elements. Therefore the controller 92 would produce a heat seal activation signal of greater duration when liquids are present, or send sealing actuation pulses to both sealing elements 441 and 442 as shown in
The sealed bag of the present invention is shown in
By incorporating the temperature sensor adjacent to the trough of the appliance, the heat seal may be controlled in a more precise manner, thereby resulting in less bag waste. This is a substantial improvement over prior art devices that are incapable of monitoring and adjusting the heat sealing process in accordance with a plurality of sensor inputs and control modes.
In addition to suspending the heat sealing operations as described above, the present invention is also capable of adjusting the control signal times based on the temperature of the elements.
The process begins in step S1702 when the temperature of the heat sealing elements is detected and sent to the controller. In step S1704 the controller adjusts the duration of the control signal applied to the heat sealing elements based on their real-time detected temperature. As per the algorithm mentioned above, more or less current may be applied to the elements based on their sensed temperature. For example a warm heating element may require 3 seconds of current to produce a seal, whereas a cold heat sealing element may require 5 seconds of current to produce a similar heat seal. In addition to varying the activation signal duration, other embodiments may adjust the amplitude and/or duration of the control signal in a real-time manner as applied to each individual sealing wire 441 and 442 as shown in
The algorithm enacted by controller 92 can also adjust waiting times for cooling periods. For example a wait time of 20 seconds may be required for a hot element at 150 degrees to cool down to 100 degrees, and a wait time of 10 seconds may be required for an element at 135 degrees to cool to 100 degrees. It is also contemplated that the algorithm can maintain the element temperature at some constant temperature during the sealing process.
For example, the operator may select a medium heat seal which would have a control signal duration of 4 seconds. If the temperature of the heat sealing elements was detected to be 110 degrees, 0.5 seconds of time duration may be subtracted from the control signal, as the heat sealing elements are already warm. If a substantial amount of liquid is detected by the liquid sensors, the controller may add 1.0 second of time to the duration of the control signal. This results in an appropriate control signal duration of 4.5 seconds to be applied to the heat sealing elements. The controller 92 may use an algorithm or look-up table to determine these adjusted control signal periods based on these pertinent parameters.
In another embodiment, the process as shown in
If it has been determined in step S1904 that a predetermined temperature has been exceeded, step S1906 is enacted wherein the controller produces a signal that opens a valve which enables the vacuum pump exhaust to be blown under the heat sealing elements in order to cool the elements. This process provides real-time feedback and control of the heat sealing elements temperature. This process reduces the amount of faulty seals that occur when the elements are warm from previous use and begin to prematurely melt the heat sealing layer within the vacuum packaging bags before they are completely evacuated. This process also ensures that the heat sealing elements maintain an acceptable temperature range so that they may be subsequently controlled by the controller using the methods described above.
The appliances described above show the heat sealing mechanism external to the vacuum chamber. However, the teaching of the present invention works equally well with appliances having the heat sealing mechanism internal to the vacuum chamber. One suitable example of this is commonly assigned U.S. provisional patent application 60/492,090, filed Jul. 31, 2003, and incorporated herein by reference. Additionally, the appliances described illustrate the receptacle external to the vacuum chamber. As will be appreciated, the teachings of the present invention work well with in-chamber vacuum packaging appliances.
The vacuum packaging device described herein therefore provides numerous embodiments and methods to cool the heat sealing elements and embodiments and methods to control and energize the heat sealing elements that may be used in combination or separately as desired. It will be understood by those skilled in the art that the above-presented description is provided by way of example only and is not intended to be limiting in anyway. Those skilled in the art will readily understand that numerous other embodiments of the invention are contemplated and possible which meet the scope and spirit of the invention.
Claims
1. A method for controlling a vacuum packaging appliance, said vacuum packaging appliance including a heat sealing element, a vacuum circuit, and a vacuum pump, said vacuum pump operable to evacuate gas from said vacuum circuit, said heat sealing element operable to heat seal a vacuum packaging receptacle, said method comprising:
- coupling said vacuum packaging receptacle to said vacuum circuit;
- hermetically separating said vacuum circuit from ambient;
- operating said vacuum pump to obtain a desired vacuum within said vacuum packaging receptacle;
- sensing an input related to control of said heat sealing element;
- determining an actuation control signal for energizing said heat sealing element as a function of at least said input; and
- applying said actuation control signal to said heat sealing element.
2. A method for controlling a vacuum packaging appliance as recited in claim 1, wherein said vacuum packaging receptacle is a vacuum packaging bag having three sealed sides and one unsealed side, and said coupling includes:
- engaging said vacuum circuit with said unsealed side of said vacuum packaging bag.
3. A method for controlling a vacuum packaging appliance as recited in claim 2, wherein said input is related to a temperature of said heat sealing element.
4. A method for controlling a vacuum packaging appliance as recited in claim 1, wherein said input arises from a user activated switch.
5. A method for controlling a vacuum packaging appliance as recited in claim 3, wherein said input arises from a temperature sensor.
6. A method for controlling a vacuum packaging appliance as recited in claim 2, wherein said input corresponds to a high liquid content mode, said actuation control signal corresponding to said high liquid content mode having a high liquid content sealing time period longer than a normal content mode sealing time period.
7. A method for controlling a vacuum packaging appliance as recited in claim 1, wherein said vacuum circuit contains a trough for collecting liquids while operating the vacuum pump.
8. A method for controlling a vacuum packaging appliance as recited in claim 7, wherein said input arises from a sensor monitoring a fluid level present in the trough of said vacuum circuit.
9. A method for controlling a vacuum packaging appliance as recited in claim 5, wherein said heat sealing element is controlled in accordance with a plurality of inputs.
10. A method for controlling a vacuum packaging appliance as recited in claim 9, wherein said vacuum pump operation is delayed until said temperature of said heat sealing element cools to a predefined temperature which tends to prevent premature sealing of said vacuum packaging receptacle.
11. A method for controlling a vacuum packaging appliance as recited in claim 1, wherein said input is related to a time period since said heat sealing element has been actuated.
12. A method for controlling a vacuum packaging appliance as recited in claim 9, wherein a duration and amplitude of said activation control signal may be changed.
13. A method for controlling a vacuum packaging appliance as recited in claim 1, further comprising providing said user feedback related to operation of said heat sealing element.
14. A method for controlling a vacuum packaging appliance as recited in claim 13, further comprising providing said user feedback related to operation of said vacuum pump.
15. A method for controlling a vacuum packaging appliance as recited in claim 14, wherein lights on a control panel provide said user feedback relating to the operation of said heat sealing element and said vacuum pump.
16. A vacuum packaging appliance for evacuating a container comprising:
- a base defining an upper support surface adapted to receive an open end of a container;
- a lid operatively associated with said base, said lid and said base defining a vacuum chamber therebetween to receive said open end of said container;
- at least one gasket surrounding said vacuum chamber for directly engaging said container such that said open end of said container is operatively associated with said vacuum chamber;
- a vacuum source operatively associated with said vacuum chamber for selectively evacuating said vacuum chamber and said operatively associated container;
- a trough coupled to the base for receiving the open end of a container and collecting contents taken from the container while evacuating said container, wherein a heat sealing element is located adjacent to the trough in order to heat seal the evacuated container; and
- a heat sealing controller that allows an operator to select a type of heat seal formed on the evacuated container.
17. The vacuum packaging appliance of claim 16 wherein said heat sealing controller controls the electrical current supplied to the heat sealing element.
18. The vacuum packaging appliance of claim 16 further comprising a control panel that allows the operator to select between 3 types of heat seals.
19. The vacuum packaging appliance of claim 18 wherein said control panel is operatively connected to the heat sealing element controller.
20. The vacuum packaging appliance of claim 18 wherein said heat sealing element controller may suspend heat sealing for a predetermined period of time in order to avoid heat seal element overheating.
21. A method of controlling a vacuum packaging appliance to evacuate and seal a container comprising the acts of:
- placing a first end of a container into a trough within a vacuum packaging appliance;
- evacuating the container of gases;
- selecting a type of heat seal for the container;
- positioning a heat sealing element to heat seal the container; and
- controlling the amount of current applied to heat sealing elements based on the selected type of seal.
22. The method of claim 21 wherein the heat sealing elements are positioned in the trough of the vacuum sealing device.
23. The method of claim 21 wherein the heat sealing element is positioned on a lid of the vacuum sealing device.
24. The method of claim 21 wherein the heat sealing element is positioned to minimize the length of the container necessary for vacuum sealing.
25. The method of claim 21 wherein controlling the amount of current to the heat sealing element may include waiting a predetermined period of time before supplying current to the heat sealing element in order to avoid overheating or premature sealing of the container.
26. The method of claim 21 wherein controlling the amount of current to the heat sealing element may include controlling the current based on the temperature of the heat sealing elements or the presence of liquid within the trough.
27. A vacuum packaging appliance for evacuating a container comprising:
- a trough for receiving the open end of a container and collecting contents taken from the container while evacuating said container,
- a heat sealing element located adjacent to the trough in order to heat seal the evacuated container; and
- a heat sealing controller that allows an operator to select a type of heat seal formed on the evacuated container.
28. The vacuum packaging appliance of claim 27 wherein said heat sealing controller controls the power supplied to the heat sealing elements.
29. The vacuum packaging appliance of claim 28 wherein a liquid sensor is connected to said heat sealing controller.
30. The vacuum packaging appliance of claim 29 wherein a temperature sensor is connected to said heat sealing controller
31. The vacuum packaging appliance of claim 29 wherein the liquid sensor is located in the trough.
32. A vacuum packaging appliance for use in evacuating vacuum packaging receptacles, said vacuum packaging appliance comprising:
- a vacuum pump;
- a vacuum circuit coupled to said vacuum pump such that actuation of said vacuum pump evacuates said vacuum circuit, said vacuum circuit intended for evacuating a vacuum packaging receptacle;
- a heat sealing element arranged to hermetically seal said vacuum packaging receptacle;
- a user input device enabling a user to select a mode of operation from among at least a first and a second operating mode; and
- a heat sealing element controller operable to actuate said heat sealing element according to a first control profile associated with said first operating mode and a second control profile associate with said second operating mode, said heat sealing element controller responsive to said user input device.
33. A vacuum packaging appliance as recited in claim 32, wherein said user input device includes a toggle switch configurable to at least a first position corresponding to said first operating mode and a second position corresponding to said second operating mode.
34. A vacuum packaging appliance as recited in claim 32, wherein said heat sealing element controller includes a microprocessor.
35. A vacuum packaging appliance as recited in claim 32, wherein said heat sealing element controller includes an application specific integrated circuit (ASIC).
36. A vacuum packaging appliance as recited in claim 32, wherein said heat sealing element controller includes a programmable logic device (PLD).
37. A vacuum packaging appliance for use in evacuating a vacuum packaging receptacles, said vacuum packaging appliance comprising:
- a vacuum pump;
- a vacuum circuit coupled to said vacuum pump such that actuation of said vacuum pump evacuates said vacuum circuit, said vacuum circuit intended for evacuating a vacuum packaging receptacle;
- a heat sealing element arranged to hermetically seal said vacuum packaging receptacle;
- a sensor providing data related to said heat sealing element; and
- a heat sealing element controller operable to actuate said heat sealing element according to a control profile that is a function of said data related to said heat sealing element.
38. A vacuum packaging appliance for use in evacuating vacuum packaging receptacles as recited in claim 37, wherein said sensor measures a parameter related to a temperature of said heat sealing element.
39. A vacuum packaging appliance for use in evacuating vacuum packaging receptacles as recited in claim 38, wherein said sensor measures a parameter related to a fluid level in said vacuum circuit.
40. A vacuum packaging appliance for use in evacuating vacuum packaging receptacles, said vacuum packaging appliance comprising:
- a vacuum pump;
- a vacuum circuit coupled to said vacuum pump such that actuation of said vacuum pump evacuates said vacuum circuit, said vacuum circuit intended for evacuating a vacuum packaging receptacle;
- a heat sealing element arranged to hermetically seal said vacuum packaging receptacle;
- a control panel to allow an operator to select a type of heat seal for sealing the vacuum packaging receptacle;
- a sensor providing data related to a temperature of the heat sealing element;
- a sensor providing data related to an amount of liquid present in the vacuum circuit while evacuating the vacuum packaging receptacle; and
- a heat sealing element controller operable to actuate said heat sealing element with a control signal; wherein the duration of the control signal is determined by the type of heat seal selected, the temperature of the heat sealing element, and the amount of liquid present.
41. A heat sealing device used in a vacuum packaging appliance comprising:
- a heat sealing element for hermetically sealing a vacuum packaging container placed in the vacuum packaging appliance;
- a temperature sensor for sensing the temperature of the heat sealing element; and
- a heat sealing element controller that controls the temperature of the heat sealing element based on a signal from the temperature sensor.
42. The heat sealing device of claim 41, wherein the heat sealing element controller controls the amount of current applied to the heat sealing element in order to control the temperature of the heat sealing element.
43. The heat sealing device of claim 42, wherein the heat sealing element controller increases the amount of current when the temperature of the heat sealing element is less than a predetermined temperature.
44. The heat sealing device of claim 43, wherein the heat sealing element controller decreases the amount of current when the temperature of the heat sealing element is greater than a predetermined temperature.
45. The heat sealing device of claim 44, wherein the heat sealing element controller maintains the heat sealing element temperature at a constant predetermined temperature.
46. A vacuum packaging appliance for use in evacuating vacuum packaging receptacles, said vacuum packaging appliance comprising:
- a vacuum pump;
- a heat sealing element arranged to hermetically seal said vacuum packaging receptacle;
- a temperature sensor providing data relating to a temperature of the heat sealing element; and
- a heat sealing element controller operable to actuate said heat sealing element with a control signal, wherein the heat sealing element controller also directs exhaust of the vacuum pump under the heat sealing element when the temperature of the heat sealing element has exceeded a predetermined temperature.
47. The vacuum packaging appliance of claim 46, wherein the heat sealing element controller sends a signal to open a valve when the temperature exceeds a predetermined temperature.
48. The vacuum packaging appliance of claim 47, wherein the exhaust of the vacuum pump is directed through a passage below the heat sealing element.
49. The vacuum packaging appliance of claim 47, wherein the temperature of the heat sealing element is maintained within a predetermined temperature range.
50. The vacuum packaging appliance of claim 47, wherein the heat sealing element controller provides a signal to activate the heat sealing elements based on one or more inputs.
51. The vacuum packaging appliance of claim 50, wherein the inputs include heat sealing element temperature, amount of liquid present in a trough, and operator selections of desired heat seals.
52. A vacuum packaging appliance for use in evacuating and sealing a vacuum packaging receptacle, said vacuum packaging appliance comprising:
- a vacuum pump for evacuating a vacuum packaging receptacle;
- heat sealing elements arranged to hermetically seal said vacuum packaging receptacle; wherein the heat sealing elements comprise two wires;
- a temperature sensor providing data relating to a temperature of the heat sealing elements; and
- a heat sealing elements controller operable to actuate said heat sealing elements with a control signal, wherein the controller determines if one or both of the wires of the heat sealing elements are to be actuated based on a predetermined condition.
53. The vacuum packaging appliance of claim 52, wherein the heat sealing element controller determines that only one wire is to be actuated when the predetermined condition is that a current temperature exceeds a predetermined temperature.
54. The vacuum packaging appliance of claim 52, wherein the heat sealing element controller determines that both wires are to be actuated when the predetermined condition is that a current temperature is below a predetermined temperature.
55. The vacuum packaging appliance of claim 52, wherein the predetermined condition is a user selected mode of operation.
56. The vacuum packaging appliance of claim 52, wherein the heat sealing element controller determines that both wires are to be actuated when the predetermined condition is that the presence of liquid is detected.
57. A method for controlling a vacuum packaging appliance for use in evacuating and sealing a vacuum packaging receptacle, comprising the acts of:
- evacuating a vacuum packaging receptacle;
- providing two heat sealing element wires to seal the vacuum packaging receptacle;
- providing a heat sealing element controller operable to actuate said heat sealing element wires with a control signal, wherein the controller determines if one or both of the wires of the heat sealing elements are to be actuated based on a predetermined condition.
58. A method for controlling a vacuum packaging appliance as in claim 57, wherein the heat sealing element controller determines that only one wire is to be actuated when the predetermined condition is that a current temperature exceeds a predetermined temperature.
59. A method for controlling a vacuum packaging appliance as in claim 57, wherein the heat sealing element controller determines that both wires are to be actuated when the predetermined condition is that a current temperature is below a predetermined temperature.
60. A method for controlling a vacuum packaging appliance as in claim 57, wherein the predetermined condition is a user selected mode of operation.
61. A method for controlling a vacuum packaging appliance as in claim 57, wherein the predetermined condition is that the presence of liquid is detected.
62. A method for controlling a vacuum packaging appliance having an evacuation mechanism and a sealing mechanism, the method comprising:
- preheat energizing a sealing mechanism in order to preheat bag material disposed within the vacuum packaging appliance; and
- seal energizing the sealing mechanism in order to seal the bag material disposed within the vacuum packaging appliance.
63. A method as recited in claim 62, wherein the preheat energizing step is performed in conjunction with an evacuation step.
64. A method as recited in claim 63, wherein the preheat energizing step brings the sealing mechanism to a lower temperature than the seal energizing step.
65. A vacuum packaging appliance for use in evacuating vacuum packaging receptacles, said vacuum packaging appliance comprising:
- a vacuum pump coupled with a vacuum chamber, said vacuum chamber arranged to receive a vacuum packaging receptacle;
- a heat sealing element arranged to hermetically seal said vacuum packaging receptacle, said heat sealing element disposed inside of said vacuum chamber;
- a temperature sensor providing data relating to a temperature of the heat sealing element; and
- a heat sealing element controller operable to actuate said heat sealing element with a control signal, wherein the heat sealing element controller also directs exhaust of the vacuum pump under the heat sealing element when the temperature of the heat sealing element has exceeded a predetermined temperature.
Type: Application
Filed: Jul 21, 2004
Publication Date: Feb 3, 2005
Inventors: Charles Albritton (Hercules, CA), Landen Higer (Alameda, CA)
Application Number: 10/897,327