US20090090353A1

US20090090353A1 - Apparatus and Method for a Self-Contained Heating Vessel

Info

Publication number: US20090090353A1
Application number: US11/461,237
Authority: US
Inventors: Daniel Grunberg; Gerhard Pawelka; Harald Quintus-Bosz
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-10-27
Filing date: 2006-07-31
Publication date: 2009-04-09
Also published as: WO2007051003A2; WO2007051003A3

Abstract

A method and apparatus for a self-contained heating vessel having enhanced efficiency and safety features. In one embodiment, the vessel includes a chamber for containing fuel; a burner assembly for burning the fuel; a fuel delivery mechanism that delivers the fuel from the chamber to the burner assembly; and a container disposed adjacent to the heat exchanger assembly, the container including an opening to an interior portion of the container. In other aspects, the vessel includes an ignition assembly operatively connected to said burner assembly and a heat exchanger assembly disposed adjacent to the burner assembly. In further aspects, the vessel includes a displacement sensor to prevent operation when displaced from an intended operating position and a pressure regulator that controls delivery of fuel to the burner assembly to maintain a substantially constant heating profile over a varying temperature range.

Description

RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. application Ser. No. 11/383,683, filed May 16, 2006, which itself claims priority to U.S. Provisional Patent Application 60/731,401, filed Oct. 27, 2005, the contents of both of which are incorporated by reference. The present application claims priority to U.S. Provisional Patent Application 60/731,401, filed Oct. 27, 2005.

FIELD OF THE INVENTION

The present application is directed to the field of heating and heat exchange and more particularly to a method and apparatus for a portable self-contained heating vessel having enhanced efficiency and safety features.

BACKGROUND OF THE INVENTION

A vessel that is capable of self-contained heating, namely a heating vessel which contains the necessary components included there within to heat a substance, is desirable for many outdoor and other uses, including camping and other situations in which many modes of cooking and heating foods and liquids are not readily available or easily performed. The portability of such a self-contained heating vessel enables the vessel to be carried with the user and utilized effectively to heat food, water and other comestibles when needed and without the necessity of packing unwieldy cooking units or having to rely on the inefficiency and inconsistency of a camp fire.
Certain self-heating cups and kettles are known in the prior art, examples of which are described below.
U.S. Pat. No. 4,191,173 to Dedeian et al. describes a self-heating cup including a cup formed of a cylindrical vessel and a hollow carrying handle attached to the vessel containing a liquid fuel reservoir from which fuel in a gaseous state is conducted to a burner located beneath a domed portion of the bottom wall of the vessel.
U.S. Pat. No. 5,690,094 to Sheinfeld et al. describes a gas flame kettle including a housing, a gas burner contained within the housing, a container for the fluid to be heated positioned within the housing and above the burner, and an exhaust duct leading from an area above the burner, through the container, and out of a surface of the housing. Excess heat and combustion gases are exhausted in heat-exchanged contact with fluid in the container via the ducts, for augmented heating of the fluid with simultaneous protection and insulation of the housing.
U.S. Patent Application Publication No. 2004/0011350 to Dowst et al. describes a heating vessel including a chamber having enclosed sides, a thermally conductive bottom end and a top end forming an opening for the introduction and extraction of contents to be heated, the bottom end having an external bottom side. A heater comprising a heat exchanger and a heat source having a heat outlet disposed at a fixed distance from the external bottom side and configured to deliver heat to a central area thereof. The heat exchanger includes a series of thermally conductive radially disposed fins that are coupled circumferentially about the central area of the external bottom side, the fins extending for a fixed distance to encase the heat outlet. A gas flow path is formed to allow intake of air and output of exhaust.
It has been determined that of particular importance in the design of a self-contained heating vessel is the cabability of the vessel to be used in a safe and efficient manner. Accordingly, there is a need for a self-contained heating vessel that offers enhancements in such areas as safety and efficiency.

SUMMARY OF THE INVENTION

A method and apparatus for a self-contained heating vessel having enhanced efficiency and safety features is disclosed. In one aspect, the vessel includes a chamber for containing fuel; a burner assembly for burning the fuel; a fuel delivery mechanism that delivers the fuel from the chamber to the burner assembly; and a container disposed adjacent to the heat exchanger assembly, the container including an opening to an interior portion of the container. In other aspects, the vessel includes an ignition assembly operatively connected to said burner assembly and a heat exchanger assembly disposed adjacent to the burner assembly. In another aspect, the vessel further includes a control assembly operatively connected to at least one of the fuel delivery mechanism and the burner assembly, the control assembly including a displacement sensor that monitors a position of the heating vessel and prevents operation of the fuel delivery/burner assembly if the heating vessel is displaced from an intended operating position. In yet another aspect, the fuel delivery assembly further includes a pressure regulator that controls delivery of the fuel to the fuel delivery/burner assembly and maintains a substantially constant heating profile over a varying temperature range.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described with reference to the several figures of the drawings, in which:

FIG. 1A is an exploded view of a self-contained heating vessel according to one embodiment of the invention;

FIG. 1B is an exploded view of the heating vessel illustrating various components of the assemblies of FIG. 1A;

FIG. 2 is a perspective view of control assemblies of a self-contained heating vessel according to another embodiment of the invention;

FIG. 3 is a side view of the heating vessel according to the embodiment of the invention illustrated in FIG. 2; and

FIG. 4 is a perspective view of a self-contained heating vessel according to another embodiment of the invention;

FIG. 5 is an enlarged perspective view of fuel delivery and operational control assemblies of the self-contained heating vessel shown in FIG. 4.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention that is claimed. It may be noted that, as used in the specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. References cited herein are hereby incorporated by reference in their entirety, except to the extent that they conflict with teachings explicitly set forth in this specification.
A method and apparatus for a self-contained heating vessel is disclosed. Examples of beneficial features and components provided by the various described embodiments of the self-contained heating vessel, discussed in detail below, include: (1) built-in fuel supply; (2) built-in pot or cup; (3) quick and convenient to set up (no pot to attach, no fuel to attach, etc.); (4) easy to operate (no knobs to adjust, no matches needed); (5) one button press on, automatic ignition, easily turned off; (6) turns off automatically; (7) stable; (8) expandable capacity; (9) no exposed flames; (10) low carbon monoxide (CO) output; (11) turns off when tipped or when bottom not placed on a firm surface; (12) inside of pot is smooth (like a standard pot) and facilitates cleaning; (13) wind screen provides wind protection; (14) more efficient than standard camping stove in terms of heat wasted; (15) turns off in over heated condition (e.g., water boils away); (16) a pressure regulator gives the device a constant heating profile over varying temperatures; and (17) lower gas pressure allows use of lighter weight plastic fuel tanks instead of heavy steel ones as typically used in canister stoves.
Referring now to the figures of the drawing, the figures constitute a part of this specification and illustrate exemplary embodiments of the invention. It is to be understood that in some instances various aspects of the invention may be shown schematically or may be exaggerated to facilitate an understanding of the invention.
FIG. 1A illustrates an exploded view of a self-contained heating vessel 100 in accordance with one embodiment of the present invention. The heating vessel 100 includes a heat exchanger assembly 102, a fuel delivery/burner assembly 104, a operation control assembly 106 and a housing assembly 108. Briefly, the heat exchanger assembly 102 provides a mechanism by which heat generated by the fuel delivery/burner assembly 104 during the conversion of a pressurized fuel to a heating flame may be transmitted to the contents of a container. Additionally, associated with the fuel delivery/burner assembly 104 is a operation control assembly 106 capable of providing an initial ignition source for igniting the fuel supplied to the fuel delivery/burner assembly. The operation control assembly 106 may further be used to ensure that the fuel delivery/burner assembly 104 is not extinguished unintentionally during use. Associated with the heat exchanger assembly 102, fuel delivery/burner assembly 104, and operation control assembly 106 is the housing assembly 108. The housing assembly 108 serves to orient the aforementioned assemblies (102, 104, 106) in a desired position, provides the structure for the container in which food or liquid is heated, enables the vessel to be comfortably and ergonomically handled by a user, and provides for a cosmetically appealing arrangement.
FIG. 1B is an exploded view of the heating vessel 100 illustrating the various components of the aforementioned assemblies of FIG. 1A. Addressing the heat exchanger assembly 102, a container 200 and a heat exchanger (or heat sink) 202 are associated with each other such that heat provided to the heat exchanger 202 may be transmitted to the container 200 via conductive, convective and/or radiative heat transfer. The container 200 is manufactured from a thermally conductive material, such as but not limited to aluminum alloy, steel alloy or conductive plastics.
In the illustrated embodiment, the heat exchanger 202 includes a plurality of protrusions 204 from the base 206 of the heat exchanger 202. These protrusions 204 serve to maximize the available surface area of the heat exchanger 202, thereby maximizing the potential conductive and convective heat transfer to the base of the heat exchanger 202 and eventually to the container 200. One skilled in the art will readily recognize that numerous alternate embodiments of the heat exchanger may be employed such that heat transfer from the heat exchanger 202 to the container 200 is maximized. Furthermore, the container 200 of the present embodiment may take numerous alternate arrangements which maintain the functionality and scope of the present invention. For example, the container 200 may be of varying shape, size and material. In other embodiments, the container 200 may be constructed using a deep draw manufacturing method.
Additionally, the container 200 may be of adaptable size, such that volume extenders 208 a may be readily attached to the upper region 208 of the container 200 to increase the available volume of the container 200. The volume extenders 208 a may attach to the upper region 208 of the container 200 using a variety of readily available mechanical fastening means, as understood by one skilled in the art, including but not limited to frictional fits or threaded fastening arrangements. The volume extenders 208 a provide the ability to adjust capacity of the cup or pot (for example, no extender, 14 oz, extended to 24 oz and further extended to 32 oz). This allows the user to choose the necessary size for their trip (depending on number of people, type of food desired, etc.) with the same base assembly along with the required extenders. Further, the extenders allow the device to be more stable when only heating 8 oz of soup or chocolate versus heating a 32 oz meal. This provides safety in a tent or uneven surface or windy conditions. The user does not have to sacrifice the benefits of a lightweight and small device to get a useful device for larger needs. The extenders are leak proof when attached to pot rim and are made of material that can withstand boiling temperatures.
In heat transmissive communication with the heat exchanger assembly 102 is a fuel delivery/burner assembly 104. In the present illustration, the fuel delivery/burner assembly 104 includes a perforated burner plate 402. The perforated burner plate 402 includes a plurality of perforations capable of delivering pressurized fuel stored in a gas tank 414. The perforations of the perforated burner plate 402 are sized and orientated to deliver a maximum amount of heat, by way of a flame, to the heat exchanger 202, while simultaneously providing a sufficient amount of heat to adequately heat the contents of the deep drawn container 200. Additionally, the sizing and arrangement of the perforations of burner plate 402 is such that the generation of excessive carbon monoxide and carbon dioxide is minimized, thereby allowing the use of the heating vessel 100 in a contained environment.
Associated with the burner plate 402 is a burner body 404, wherein said burner body 404 is mechanically fastened to the burner plate 402. Attachment of the burner plate 402 to the burner body 404 may be accomplished using a variety of means including brazing, soldering, welding or alternative mechanical fastening means. Additionally, one skilled in the art will readily recognize that the burner plate 402 and burner body 404 may be manufactured as a single assembly using a variety of manufacturing means such as deep drawing and stamping. Manufacturing the burner plate 402 and burner body 404 as a single assembly thereby prevents the need for mechanical fastening means and prevents potential leaks in the interface between the burner plate 402 and the burner body 404. The burner plate 402 and burner body 404 may be manufactured form a variety of suitable materials including but not limited to brass alloys, copper alloys, aluminum alloys or steel alloys, and any combination thereof.
Tangentially associated with the burner body 404 is an orifice assembly 406. The orifice assembly 406 may be manufactured from a compatible material as the burner plate 402 and burner body 404 such that the interface joint between the orifice assembly 406 and the burner body 404 may be mechanically fastened. Suitable fastening means include but are not limited to brazing, silver soldering or friction welding. The orifice assembly 406 allows for the mixing of combustion air and a compressed fuel thereby allowing a partially aerated fuel mixture within the burner body 404. The pressurized fuel, stored in a gas tank 414, is delivered to the orifice assembly 406 via a gas delivery tube 412. The gas delivery tube may be manufactured from a variety of suitable materials compatible for deliver of the compressed fuel. For example, the gas delivery tube may be manufactured from a copper allow or a plastic composition. The gas tube 412 may be flexible in nature, readily allowing assembly of the heating vessel 100, or may be rigid in nature.
Compressed fuel delivered to the orifice assembly 406 may be delivered at a controllable pressure, such that burner efficiency is maintained irrespective of the pressure of the compressed case within the gas tank 414. Delivery pressure of the compressed gas from the gas tank 414 may be maintained by a pressure regulator 416 located between the gas tank 414 and the orifice assembly 406. The pressure regulator 416 may be fixed, thereby delivering a constant pressure to the orifice assembly 406 or may be variable such that a user may selectively alter the delivered pressure of the compressed gas based upon the users demands. Furthermore, the pressure regulator 416 may be altitude compensating, such that gas pressure is varied based upon the operating altitude of the heating vessel 100. In light of this, relatively constant combustion rates and flame sizes may be maintained at a burner unit (see, for example burner plate 402 and burner body 404 of FIG. 1B) of the fuel delivery/burner assembly 104 at varying altitudes. The pressure regulator allows the flames to remain approximately constant in heat output, appearance and height over a varying temperature range (constant output impedance), thereby facilitating low CO output and efficiency over a wide temperature range. The pressure regulator gives the device a constant heating profile for temperatures from approximately 40 F to approximately 120 F. In another embodiment, the device provides a low primary and secondary flame height in a compact small diameter package that is suitable for a portable stove. In the absence of any control mechanism for the fuel flow, the flames would either be too large at high ambient temperatures, or they would be too small at low ambient temperatures. Although the inclusion of a user control knob for adjusting fuel flow is contemplated herein, the inclusion of a pressure regulator allows for the a user control mechanism for fuel flow to be eliminated while still providing the constant heating profile at varying altitudes and temperature ranges.
In still another embodiment, pressure is maintained at low temperatures by heating the gas tank 414. In some embodiments, this is accomplished by directing heat exhaust from the burner assembly 104 to flow around the gas tank 414. In another embodiment, a conductive element (not shown) may be provided to conduct heat from the burner assembly 104 to the gas tank 414. In one embodiment, the conductive element is heated using exhaust gases. In another embodiment, the conductive element is heated using flame from the burner.
Further, with respect to carbon monoxide output, ANSI standard Z21.72 allows for 800 ppm. Many stoves exceed this and, presumably, are not ANSI compliant. When flames hit a metal surface they quench (go out) and produce unburned fuel (inefficient) and CO. By using a low flame height and keeping the power output low, the device of the present embodiment mitigates the production of unburned fuel and provides low CO output. The pressure regulator allows for this constant flame height without allowing the user to turn up the flame height to unsafe levels. The design of the present embodiment of the invention provides for a much lower CO output than even the ANSI provides for a more compact (vertically) design, which is important for stability.
In one embodiment, a vessel of the present invention utilizes butane only (no added propane), thus the lower gas pressure allows the use of a lighter weight plastic fuel tank versus the heavy steel ones required for canister stoves. Standard canister stoves generally have no regulator and have flames varying with temperature. They also use propane mixed with the butane for fuel that increases the pressure at low temperatures.
The gas tank 414 may be a sealed unit pre-filled prior to purchase of the heating vessel 100 or in the alternative may allow subsequent refilling by a user upon exhausting of the initial supply. In the illustrated embodiment, the gas tank 414 includes a refill port 418 capable of mating to an external fuel supply (not shown) for refilling of the compressed gas tank 414. Furthermore, the gas tank 414 may be manufactured from a variety of suitable materials, including but not limited to steel or aluminum alloys or a plastic or phenolic composition. Selection of materials may be based upon the anticipated operating conditions of the heating vessel as well as the anticipated gas pressured which the gas tank 414 contains.
The fuel delivery/burner assembly 104 is connected to a operation control assembly 106 capable of both igniting the burner unit of the fuel delivery/burner assembly 104 as well as shutting off the burner unit in the event that the flame of the fuel delivery/burner assembly 104 is extinguished or fails to ignite. This prevents the escape of unburned fuel gas, which can be an explosion hazard. In another embodiment, the heat control assembly also turns off the fuel delivery/burner assembly when the contents of the cup (e.g. water) reaches a certain temperature or if the contents are boiling. This feature is performed by a mechanical temperature detection method or by steam detection. Possibilities include heat passing along a bimetallic part with temp difference detection and/or rate detection via a rising thermostat, as further discussed below. The structural components are in communication with the gas valve to control delivery of gas to the fuel delivery/burner assembly accordingly.
In another embodiment, the operation control assembly 106 extinguishes the fuel delivery/burner assembly 104 in the event that the heating vessel 100 is displaced from an intended operating position. Safety Features and components of the operation control assembly 106 that prevent operation of the fuel delivery/burner assembly are discussed below (see e.g. heat control assemblies and tilt monitor assembly referenced with respect to FIGS. 2 and 3) Further, the device is also designed for enhanced stability because pot integrated into the unit and having a low center of gravity and a wide base yet is still usable as a drinking mug or cup.
The operation control assembly 106 includes an igniter 602, capable of being depressed by an ignition button 604, to deliver a spark to the burner plate 402 region. In the present illustrated embodiment, the igniter 602 may be a spring loaded piezo igniter having a structure that would be understood by one skilled in the art. The spring loaded piezo igniter generates a high voltage which is delivered via the piezo igniter transmission line 620 to the burner plate 402 region. The transmission line 620 of the piezo igniter 602 may terminate in a spark gap, wherein a spark can jump between a conductor in the piezo igniter transmission line 620 and the burner plate 402 assembly.
Actuation of the piezo igniter 602 is accomplished using the ignition button 604. Additionally, the ignition button 604 actuates a gas control system valve 608 upon an initial depressing of the ignition button 604, such that the gas control valve 608 allows for delivery of a compressed fuel from the gas tank 414 to the orifice assembly 406. Actuation of the gas control valve 608 is accomplished via an actuating rod 606 associated with the ignition button 604 and the gas control valve 608. One skilled in the art will readily recognize that numerous alternative gas control valve 608 arrangements may be utilized with the heating vessel of 100. Furthermore, the actuation of the gas control valve 608 during operation of the ignition button 604 may be accomplished using a variety of mechanical means as understood by one skilled in the art. For example, the piezo igniter 602, gas control valve 608 and ignition button 604 may be a discrete sealed unit. In the alternative, the gas control valve 608 may be manually controlled by an operator, wherein an operator opens the gas control valve 608 prior to the depressing of the ignition button 604.
In the presently described embodiment, a heat control assembly 610 is additionally associated with the ignition button 604. The heat control assembly 610 of the present embodiment is further in thermal contact with the container 200, such that the temperature of the container 200 may be monitored by the heat control assembly 610. In the event that the temperature of the container 200 exceeds a predetermined operating parameter, the temperature control assembly 610 operates the actuating rod 606 to close the gas control valve 608, thereby extinguishing the flame at the burner plate 402. Control of the gas control valve 608 by the heat control assembly 610 prevents the overheating of the heating vessel 100. Additionally, the temperature control assembly 610 may further include a tilt monitor mechanism that monitors the tilting of the device and extinguish the fuel delivery/burner assembly accordingly when the tilt monitor mechanism measures a degree of tilt that exceeds a predetermined limit, as further discussed elsewhere herein.
In another embodiment, the temperature control assembly 610 may be a bimetallic switch. The bimetallic switch includes an assembly of two distinct metals, each of which has a different coefficient of expansion. Upon heating of the container 200 by the fuel delivery/burner assembly 104 the bimetallic switch is gradually heated. Heating of the bimetallic switch thereby causes the two metals of the bimetallic switch to gradually expand as governed by their individual coefficient of expansion. The rate of expansion, as dictated by the desired maximum temperature of the container 200, may be utilized in determining the appropriate displacement of the bimetallic switch. Temperatures exceeding this predetermined maximum temperature will result in movement of the bimetallic switch beyond the operating displacement, thereby actuating the actuating rod 606 and closing the flow of gas through the gas control valve 608. The flame at the burner plate 402 is therefore extinguished, and the temperature of the container 200 drops. Once the temperature of the container is below the maximum threshold temperature of the bimetallic switch, the gas control valve 608 may once again by actuated by the actuating rod 606 upon operating of the ignition button 604. One skilled in the art will readily recognize that control of the gas control valve 608 based upon container 200 temperature may be accomplished using a variety of acceptable alternative means. The illustration of a bimetallic switch, therefore, is not intended to be limiting of the acceptable scope of suitable alternatives for use as a temperature control assembly 610.
Associated with the heat exchanger assembly 102, fuel delivery/burner assembly 104 and the operation control assembly 106 is the housing assembly 108. This housing assembly 108 may take numerous forms, manufactured from a variety of suitable materials, such that the heat exchanger assembly 102, fuel delivery/burner assembly 104, and operation control assembly 106 are properly orientated. In one embodiment the housing assembly 108 may be manufactured from, but not limited to, a plastic or composite material.
Surrounding the container 200 is a cup lip 802. The cup lip 802 is sized and orientated to allow delivery and removal of the contents of the container 200 in an efficient manner. Additionally, the cup lip of the illustrated embodiment serves to locate a multipart shell or chassis 804. This multipart chassis 804 serves to orientate the components of the heat exchanger assembly 102, fuel delivery/burner assembly 104 and operation control assembly 106 while simultaneously providing a cosmetically appealing surface. Due to the heat production of the fuel delivery/burner assembly 104, the multipart chassis 804 may include an insulating region, which aid in maintaining a comfortable outer surface temperature of the heating vessel. This insulating region may include, but is not limited to, the use of insulating materials such as fiberglass or aramid fibers, may be a suitable sized air gap or any combination thereof. Further, the shell 804 may include shielding components to keep flames from being exposed and to provide a wind screen, thereby enhancing safety of the device.
In communication with the multipart chassis 804 is a handle assembly 806 sized and orientated for use by a user. Disposed on the handle assembly 806, in the present embodiment, is a safety switch 810 which must be engaged prior to operating of the ignition button 604. One skilled in the art will readily recognize that the safety switch may take numerous forms, including a switch that must be depressed prior to operation of the ignition button 604, or a cover over the ignition button 604 that must first be lifted prior to operating the ignition button 604. The safety switch 810 therefore prevents unintended operation of the heating vessel 100.
Disposed along the bottom of the heating vessel 100 of the present illustrated embodiment is a heat shield 808. This heat shield 808 serves to reflect the heat generated by the fuel delivery/burner assembly 104 toward the heat exchanger assembly 102 and aid in maintaining a comfortable exterior operating temperature of the heating vessel 100. One skilled in the art will readily recognize the heat shield 808 may be manufactured from a plurality of suitable temperature resistant materials including but not limited to steel alloys or high temperature composites.
The cup lip 802, multipart cup chassis 804, handle 806 and heat shield 808 may be mechanically or chemically fastened to each other to maintain proper orientation. Mechanical fastening means include, but are not limited to, screws, bolts or engagement tabs. Chemical fastening techniques include but are not limited to glues or thermoplastic welding. One skilled in the art will readily recognize that numerous alternative fastening means are readily available which are acceptable for use with the present embodiment of the invention.
FIG. 2 is a perspective view of control assemblies of a self-contained heating vessel 1000 according to another embodiment of the invention. FIG. 3 is a side view of the heating vessel 1000 according to the embodiment of the invention illustrated in FIG. 2. A container 1200, into which the food and liquid to be heated is placed, is attached to a chassis 1804 via attachments 1210 (such as spot welds or other attachment mechanisms known to those of ordinary skill in the art) disposed adjacent to a heat exchanger 1202. The chassis 1804 may include a shield 1808 that may serve as a wind shield and/or may also serve as a heat shield to redirect heat back towards the heat exchanger 1202 and thereby improve efficiency of the system. A shell 1806 is attached to the chassis 1804 to provide a handle for gripping by the user and to provide a cosmetically appealing appearance. Portions of the chassis 1804, for example shell 1806 and/or windscreen 1808, may be translucent to allow a user to see whether a flame is on in the vessel while also providing the wind shield and/or heat shield functions noted above.
The chassis 1804 houses a button 1604 that is activated by a user to turn on a burner unit (see, for example, burner plate 402 and burner body 404 of FIG. 1B). The button 1604 has a shaft 1604 a extending along the chassis 1804 and that is communication with a return spring 1604 b that returns the button to its pre-activated position after being released by the user. The shaft 1604 a of the button is operatively connected to a gas valve 1608. When the button 1604 is activated, the shaft 1604 a engages the gas valve 1608 (e.g. via a connector arm) to open the valve and allow gas to flow from a gas tank 414 to the fuel delivery/burner assembly 104 (having components as discussed above in reference to FIGS. 1A and 1B and illustrated therein). Activation of the button 1604 also engages an igniter mechanism 1602, such as a piezo igniter, that ignites the burner unit 402, 404.
Housed within the chassis is a control mechanism 1606 that is operatively connected to the gas valve 1608. It is also contemplated that the control mechanism 1606 may be operatively connected to the igniter mechanism 1602. In the illustrated embodiment, the control mechanism 1606 is a latch lever. The latch lever 1606 is disposed between the chassis 1804 and the container 1200 and is attached to the chassis 1804 via a pivot 1614. The latch lever is biased in a position via a bias spring 1616. Alternative locations for the bias spring 1616 are shown in FIGS. 2 and 3.
Operatively connected to the latch lever 1606 are control assemblies that engage to shut off the gas valve and to prevent the flow of gas to, and hence prevent operation of, the burner unit. One embodiment of a control assembly includes a boil detect disc 1610, which is illustrated in the figures in the “cold” position. As illustrated, the center of the boil detect disk is fixed to the chassis 1804. The boil detect disc 1610 detects when the contents of the container 1200 are boiling and, upon such detection, engages to move the latch lever 1606 as an actuating arm, wherein the tip 1606 a of the latch lever 1606 disengages from button 1604, allowing button 1604 to turn off via return spring 1604 b to shut off the gas flow via gas valve 1608.
Another embodiment of a control assembly includes a heat detect disc 1612, which is illustrated in the figures in the “cold” position. As illustrated, the rim of the heat detect disc 1612 is fixed to the latch lever. The heat detect disc monitors temperature and does not allow the latch lever 1606 to latch in the on position unless flame (heat) is detected. This prevents the unit from latching in the “on” position if the flame fails to ignite for any reason. The disc unlatches the latch lever 1606 in the event of the flame extinguishing for any reason, thus disengaging the gas valve and preventing fuel from escaping into the atmosphere.
Yet another embodiment of a control assembly includes a tilt monitor mechanism 1614. In one embodiment, the tilt monitor mechanism is a cam assembly. In another embodiment, the tilt monitor mechanism 1614 includes a pendulum assembly. The tilt monitor mechanism 1614 monitors a tilt angle of the heating vessel 1000 (for example, via a cam assembly or pendulum assembly) and upon exceeding a predetermined tilt angle, the tilt monitor mechanism engages the lever latch 1606 which in turn engages the gas valve 1608 to shut off the gas flow. In still another embodiment, the tilt monitor mechanism is a snorkel and ball disposed in the gas line that shuts off gas flow when tipped. In another embodiment, the tilt monitor mechanism 1614 may also detect whether the heating vessel has been placed on a flat surface. In the event that the vessel is placed on a non-flat surface, or moved from a flat surface (tipped over or lifted up, for example), the lever latch 1606 is engaged, in the manner as noted above, which in turn engages the gas valve 1608 to shut off the gas flow.
FIG. 4 is a perspective view of a self-contained heating vessel 2000 according to another embodiment of the invention. The vessel 2000 includes a container 2100 in which foods and liquids to be heated may be placed and including a heat exchanger assembly that facilitates heat transfer from the burner assembly 2200 that is disposed adjacent to the container 2100. The burner assembly 2200 receives fuel from and is controlled by the fuel delivery and operational control assemblies 2300 (discussed in detail below in reference to FIG. 5) and produces heat that is transferred to the contents of the container 2100. Further, as illustrated, a transparent covering 2400 may be disposed around or adjacent to the burner assembly and which provides an external view of the burner assembly that enables a user to determine whether the burner is operational (e.g. whether a flame is seen). The covering 2400 may also provide a wind screen function as noted above.
FIG. 5 is an enlarged perspective view of the fuel delivery and operational control assemblies 2300 of the self-contained heating vessel shown in FIG. 4. Manual control by a user to activate the self-heating operations of the vessel is provided by button 2301 that is operationally connected to the vessel system to initiate delivery of fuel and activation of the burner assembly. Further, as illustrated, a tilt sensor assembly 2310 is in the raised position against the bias of its spring 2312 when the vessel 2000 is resting on a surface (the spring 2312 is shown extending from the tilt sensor foot 2314 all the way up to the chassis 2302). When the vessel is tilted or lifted, the tilt sensor assembly 2310 extends to an extended position (downward). At the top of the tilt sensor 2310 is a catch release cam surface 2316 that is angled from a small diameter to a large diameter and that acts on the edge of a lever assembly 2320, which in turn rotates about a pivot 2330 thereby engaging a gas valve assembly 2340 and shutting off the gas supply to the burner assembly. Thermal sensor assemblies 2350 are shown disposed on the pivoting lever assembly 2320 and are capable of shutting of the gas supply in a similar manner as operationally described above in reference to FIGS. 2 and 3.
Other embodiments of the invention will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.

Claims

1. A self-contained heating vessel, comprising:

a chamber for containing fuel;

a burner assembly for burning the fuel;

a fuel delivery mechanism that delivers the fuel from said chamber to said burner assembly;

a container disposed adjacent to said burner assembly, said container including an opening to an interior portion of said container;

a control assembly operatively connected to at least one of said fuel delivery mechanism and said burner assembly; and

a transparent covering disposed adjacent to said burner assembly that allows an external view of said burner assembly for assessing whether said burner assembly is generating a flame.

2. The vessel of claim 1, wherein said fuel delivery mechanism includes a pressure regulator that controls delivery of the fuel to said burner assembly and maintains a substantially constant heating profile over a varying temperature range.

3. The vessel of claim 1, wherein said control assembly includes a displacement sensor that monitors a position of said heating vessel and prevents operation of said burner assembly when said heating vessel is displaced from an intended operating position.

4. A self-contained heating vessel, comprising:

a chamber for containing fuel;

a burner assembly for burning the fuel;

a container disposed adjacent to said heat exchanger assembly, said container including an opening to an interior portion of said container; and

a control assembly operatively connected to at least one of said fuel delivery mechanism and said burner assembly;

wherein said control assembly includes a displacement sensor that monitors a position of said heating vessel and prevents operation of said burner assembly when said heating vessel is displaced from an intended operating position.

5. The vessel of claim 1, further comprising:

an ignition assembly operatively connected to said burner assembly.

6. The vessel of claim 1, further comprising:

a heat exchanger assembly disposed adjacent to said burner assembly.

7. The vessel of claim 1, further comprising:

8. The vessel of claim 1, wherein said displacement sensor is a tilt monitor mechanism and wherein said tilt monitor sensor prevents operation of said burner assembly when said heating vessel is tilted beyond a predetermined tilt degree.

9. The vessel of claim 8, wherein said tilt monitor mechanism is a pendulum sensor.

10. The vessel of claim 8, wherein said tilt monitor mechanism is a cam assembly sensor.

11. The vessel of claim 1, wherein said displacement sensor is a device for sensing whether said heating vessel is resting on a flat surface.

12. The vessel of claim 1, further comprising:

at least one volume extender that attaches to the container and expands a capacity of the container.

13. The vessel of claim 1, wherein said control assembly further includes a temperature sensor that monitors a temperature of the vessel and prevents operation of said burner assembly when a predetermined temperature is reached.

14. The vessel of claim 13, wherein said temperature sensor is a bimetallic switch.

15. The vessel of claim 1, wherein said beat control assembly further includes a boil detect sensor that monitors contents of the vessel for boiling and prevents operation of said burner assembly when boiling is detected.

16. The vessel of claim 5, wherein said ignition assembly is a piezo igniter.

17. The vessel of claim 1, further comprising:

a button that is operatively connected to said fuel delivery mechanism, wherein activation of said button permits delivery of fuel by said fuel delivery mechanism to said burner assembly.

18. The vessel of claim 5, further comprising:

a button that is operatively connected to said ignition assembly, wherein activation of said button controls ignition of said burner assembly.

19. A self-contained heating vessel, comprising:

a chamber for containing fuel;

a burner assembly for burning the fuel;

a container disposed adjacent to said heat exchanger assembly, said container including an opening to an interior portion of said container;

wherein said fuel delivery mechanism includes a pressure regulator that controls delivery of the fuel to said burner assembly and maintains a substantially constant heating profile over a varying temperature range.

20. The vessel of claim 19, further comprising:

an ignition assembly operatively connected to said burner assembly.

21. The vessel of claim 19, further comprising:

a heat exchanger assembly disposed adjacent to said burner assembly.

22. The vessel of claim 19, wherein said pressure regulator is fixed and provides a constant fuel pressure.

23. The vessel of claim 19, wherein said pressure regulator is variable and provides a user-selected fuel pressure.

24. The vessel of claim 19, wherein said pressure regulator is altitude compensating to provide a variable fuel pressure based on an operating altitude of the vessel.

25. The vessel of claim 19, wherein said pressure regulator maintains a substantially constant heating profile for temperatures from approximately 40 F to approximately 120 F.

26. The vessel of claim 19, wherein said pressure regulator comprises a conductive heating element applying heat to said chamber.

27. The vessel of claim 19, wherein said pressure regulator comprises a convective heating element applying heat to said chamber.

28. The vessel of claim 19, further comprising:

a control assembly operatively connected to at least one of said fuel delivery mechanism and said burner assembly.

29. The vessel of claim 28, wherein said control assembly includes at least one of a displacement sensor; a temperature control sensor; a boil detect sensor, and any combination thereof.

30. The vessel of claim 19, wherein said ignition assembly is a piezo igniter.

31. The vessel of claim 19, further comprising:

32. The vessel of claim 19, further comprising:

33. The vessel of claim 19, further comprising:

34. The vessel of claim 19, further comprising:

35. A heating vessel comprising:

a fuel supply;

a burner assembly for burning fuel from said fuel supply, said burner assembly comprising a button for igniting said burner;

a pressure regulator operatively connected with said burner assembly, said pressure regulator providing a constant heating profile over varying temperatures;

a container disposed adjacent said burner assembly;

a heat exchanger in thermal communication with said burner assembly and said container, said heat exchanger communicating heat to said container via one of convective and radiant heat; and

a wind screen protecting said burner assembly from ambient wind.