HK1038255A - Heating apparatus - Google Patents

Description

Heating device

Technical Field

The present invention relates to a heating device, and more particularly to a high efficiency heating device for heating a preselected area.

Background

LP/propane or natural gas fueled heaters, such as patio heaters, are suitable for free standing and embedded structures, which are sold primarily for commercial use. For example, in recent years, in the southwest area, a local smoking ban has been implemented, and therefore, customers of a hotel or a bar have to go outdoors to smoke, which is very inconvenient in a cold night, and thus, the patio heater has become particularly popular. Patio heaters are used to heat preselected outdoor areas, which makes smokers and those who prefer to be outdoors more comfortable.

Free-standing patio heaters, which are easily moved from place to heat preselected areas, typically have a base of sufficient size to accommodate a fuel tank and an elongated hollow mast projecting upwardly into a burner assembly housing in which air is heated by combustion of fuel gas in the fuel tank within the base. The burner assembly housing has a cylindrical wall with an aperture for the discharge of the hot products of combustion within the housing. The flow of hot gas through the wall holes heats the wall so that the wall emits radiant infrared heat. A large dome-shaped reflector cap is attached to the top of the housing and is flared downwardly to reflect heat dissipated by the housing generally downwardly around the patio heater pillar. The embedded structure, in which the heater is connected to a gas supply, for example provided by a gas utility company, is typically not moved after installation of the device, so that no base is required and thus the post extends from the ground up to the burner assembly housing. In each of the free standing and embedded structures, the burner assembly housing and the reflector dome have substantially the same configuration.

One disadvantage of the currently available patio heaters is their thermal efficiency. The perforated cylindrical wall has a portion exposed below the bottom of the dome reflector hood so that heat given off thereby may not encounter the dome and instead of being directed downwardly to heat the area surrounding the post, the heat is conveyed radially away from the heater in a generally unobstructed path, thus providing little or no heating effect to the lower area desired to be heated. Also, once the patio heater is turned on, the heating zone is a full 360 degree circle around the unit; however, for example, where the heater is near a corner of a patio, it may be difficult for a person to stand around a full 360 degree area under the cover, and thus, heating of the full area may not be required.

Another disadvantage is that the large size metal reflector dome is usually about the diameterIn inches. Large domes are expensive and difficult to store and transport in a compact manner. Also, universal packaging of the device becomes difficult because the device has a large size dome reflector which limits the ability to properly display the device and place it on a shelf for retail sale.

Accordingly, there is a need for a heating device, such as a patio heater, that better maximizes thermal efficiency. There is also a need for a heating device that can be stored and transported in a compact and cost-effective manner. Additionally, compact packable patio heaters are desirable for retail sale.

Summary of The Invention

In accordance with the present invention, a heating apparatus is provided which has improved thermal efficiency compared to existing commercial patio heaters. The heating device of the present invention includes a burner assembly housing that contains a burner assembly for combusting fuel from a fuel source. The apparatus has a thermal efficiency system that allows substantially all of the heat emitted by the housing to be used to heat a preselected area surrounding the apparatus. More specifically, the system maximizes the amount of heat directed in a substantially downward direction into a preselected area below the housing to minimize heat loss and thus the amount of fuel necessary to heat the preselected area.

In one form of the present invention, a heating apparatus aligned along a longitudinal axis is provided that includes a burner assembly for combusting fuel from a fuel source, and a burner assembly housing. The radiating surface of the housing has apertures for directing heat generated by the ignited fuel outwardly away from the housing. The radiating surface is inclined relative to the longitudinal axis for conducting heat in a substantially downward direction about the longitudinal axis to maximize the efficiency of the heat emitted through the housing to heat the preselected area. The radiant surface angling to be inclined relative to the vertical longitudinal axis of the heating apparatus avoids the need for large reflector domes which are used in existing commercial patio heaters which direct heat outwardly in a generally downward direction away from the burner assembly housing to heat preselected outdoor areas. Moreover, since the radiating surface is inclined with respect to the vertical, it conducts heat in a downward direction, thus avoiding, like the radiating surface of a cylindrical aperture, minimizing the amount of heat loss from the radiated heat directed straight radially outward, and increasing the efficiency of the device in terms of the amount of fuel necessary to keep a given area defined by the small radius around the device sufficiently warm.

In a preferred form, a cover is provided on the housing, the cover projecting radially beyond the housing to protect it from exposure to rain. The cover is spaced apart on the radiant surface along the longitudinal axis to reflect back in a downward direction about the longitudinal axis the dispersed radiant heat emitted at the housing. Preferably, the heating means comprises an elongate support member projecting upwardly into the burner assembly housing, the cover member having a longitudinal axis perpendicular theretoA fixed diameter having a length less than aboutFeet. The existing dome reflectors are very large compared to the cover of the heating device of the present invention, since large dimensions are necessary in order to be able to radiate heat from the cylindrical wall of the burner assembly housing. The inclined radiant surface provided by the present invention eliminates the need for a large dome reflector of existing patio heaters and, therefore, as noted above, allows for the use of smaller covers.

In one form, the heating apparatus includes a base of sufficient size to receive a fuel tank, the burner assembly housing being substantially smaller than the base; and an elongated support member extending along the longitudinal axis between the base and the housing. Separable connection mechanisms are provided between the support, base and housing to allow for compact shipping storage.

Preferably, the radiating surface is flat and inclined at a predetermined angle relative to the longitudinal axis to direct heat downwardly and radially outwardly from the longitudinal axis. The predetermined angle may be about 70 degrees to maximize coverage of the heated air throughout the preselected area.

In a preferred form, the radiating surface has a frustoconical shape to direct heat downwardly and radially outwardly along the longitudinal axis, and the housing further includes an upper cylindrical wall portion projecting upwardly from the top of the frustoconical radiating surface.

In another form of the invention, an upper housing assembly of a heating device is provided with an upper housing assembly containing a burner head for igniting fuel supplied thereto from a fuel source. The housing assembly includes a cylindrical wall portion having a central longitudinal axis extending therethrough and apertures in the cylindrical wall portion for emitting hot gases generated by the burning fuel. At least one wall plate (louver) extends transversely to the longitudinal axis and is adjustably connected to the housing wall portion to allow the position of the wall plate to be varied relative to the axis to direct heat emanating from its walls and apertures in a generally downward direction. The wall panel allows the use of existing commercially available patio heater burner assembly housings while eliminating the need for a large dome reflector cap to be attached thereto and substantially minimizing the loss of radiant heat directed radially outwardly from the housing without dome reflection. In addition, the adjustable wall allows the area heated by the heating device to be changed according to the specific needs of the user.

Preferably, the heating apparatus includes a base for receiving the fuel tank, the base having a predetermined radius and the distance from the central axis to the distal end of the wall panel being less than the radius of the base, so that the wall panel is of sufficient size to be placed inside the base for transport.

In a preferred form at least one of the wall panels comprises a plurality of wall panels which are mutually adjustable to vary the spacing between adjacent wall panels and minimise the risk of accidental contact with the hot wall of the housing assembly.

In one form, the wall plate has an annular body portion inclined downwardly relative to the central axis, and a bight portion spaced from a housing wall portion inclined downwardly relative to the annular body portion. Preferably, the plurality of wall panels are arranged to be adjustable relative to each other to vary the spacing between adjacent wall panels, the wall panel ring body and the bend having a predetermined radial extent, the radial extent of the ring body being about twice the spacing between adjacent wall panels and about four times the radial extent of the bend.

In another form of the invention, a controllable heating device surrounding different zones of the heating device includes a burner assembly for igniting fuel from a fuel source and a burner assembly housing having an apertured wall extending around the burner assembly for emitting heat from the housing. A heat reflector shroud is also provided which is radially larger than the housing and is disposed on the housing wall to direct the rising heated air downwardly from the housing to heat a preselected area beneath the shroud. A heating zone adjuster is disposed under the cover and adjusts the reflected heat to change the preselected zone heated by the heat of the housing. The heating zone conditioner allows the heat of the enclosure to be concentrated in the area around the desired heating means, but not in areas that are not used and do not require heating.

Preferably, the hot zone adjuster includes a movable baffle adjustment mechanism adjacent the housing wall, the movable baffle adjustment mechanism being movable between a first position and a second position, whereby substantially the entire area of the reflector hood is utilized when the movable baffle adjustment mechanism is in the first position to direct heated air emitted from the housing to heat the preselected zone, and whereby a portion of substantially the entire area of the reflector hood is utilized when the baffle adjustment mechanism is moved to the second position to direct heated air emitted from the housing to heat a different preselected zone. The movable reflective plate adjustment mechanism may include a rotatable reflective plate that is rotatable closed in a first position and rotatable open in a second position.

In one form, the heating zone adjuster may include a heat diverter proximate the housing wall, the heat diverter being adjustable to block heat emitted by a portion of the reflector. The heat diverter is adjustable to a plurality of different positions to vary the size of the reflector portion to impede heating to vary the preselected area of heating.

Brief Description of Drawings

FIG. 1 is a perspective view of a heating apparatus according to the present invention showing a cover and a base, and an elongated support member extending between the cover and the base;

FIG. 2 is a perspective view of the heating apparatus shown in FIG. 1 showing the fuel tank in the base with the gas supply line extending within the support and the burner assembly housing having an inclined apertured radiant surface at the top of the support below the cover;

FIG. 3 is an enlarged fragmentary perspective view of the arrangement of the burner assembly housing and cover member showing the housing partially cut away to provide a view of the interior of the burner assembly;

FIG. 3A is a graph of the different thermal effects obtained by comparing the heating device of the present invention of FIGS. 1-3 with a prior art heater having a cylindrical radiating surface;

FIG. 4 is a perspective view of a shipping container including the heating device of FIGS. 1-3 removed;

FIG. 5A is an elevation view of another heating device of the present invention including a frustum-shaped radiation screen;

FIG. 5B is an exploded perspective view of the alternative heating apparatus of FIG. 5A, showing the radiation assembly including a frustum-conical radiation screen for radiating heat in a generally downward and radially outward direction;

FIG. 5C is an enlarged perspective view of the bottom member of the radiant assembly provided with the vent holes;

FIG. 6 is a partial perspective view of the upper portion of another heating apparatus according to the present invention showing the placement of the burner assembly housing and reflector hood, and a glow zone adjuster under the hood adjacent the housing that allows for a change in the preselected region to be heated by the apparatus;

FIG. 7 is a schematic bottom view of the heating apparatus shown in FIG. 6, illustrating the rotatable baffle of the heating zone adjuster closed such that substantially the entire area under the reflector hood is utilized to reflect heat emitted by the housing to heat the preselected area;

FIG. 8 is a view similar to FIG. 7 showing the reflector panels rotated open, perpendicular to each other, so that a portion of the entire area of the reflector hood is utilized to reflect heat from the housing to heat each of the preselected areas;

FIG. 9 is a view similar to FIG. 8 showing the reflective plates fully open with the reflective plates all aligned so that little of the cover is available to reflect heat to further modify the heated area;

FIG. 10A is a partial perspective view of the upper portion of another heating apparatus of the present invention showing an adjustable connection of a wall plate to the burner assembly housing to vary the inclination of the wall plate and thereby the area to be heated;

FIG. 10B shows a plurality of wall panels adjustably connected to the burner assembly housing;

FIG. 11 is a perspective view of a heating device having a table and legs, a motion detector for controlling ignition of fuel when detecting motion, and an umbrella disposed on the reflector dome;

FIG. 12 is a view similar to FIG. 11 with the umbrella and table legs removed and a gas lamp positioned between the reflector dome and the burner assembly housing; and

fig. 13 is an enlarged partial perspective view of the motion detector of the heating device of fig. 11 and 12.

PREFERRED EMBODIMENTS

In fig. 1-3, a high efficiency heating apparatus 10 of the present invention is employed. The heating apparatus 10 is adapted to use natural gas or liquefied petroleum gas (LP-gas) as a fuel to generate air heated by the hot gases of combustion and the infrared heat of radiation to keep the area around the apparatus 10 warm. The apparatus 10 is often referred to as a "patio heater" because it is designed primarily for outdoor use, such as in patios outside of cafeterias and bars at night, so that customers may stay outdoors in a comfortable preselected area having a much higher temperature than cold outdoor temperatures. As shown, the patio heater 10 has a base 12 at the bottom of an elongated support or mast 14. As shown in fig. 2, the base 12 has an interior space 16 containing a tank 18 of liquefied petroleum gas.

The base interior 16 is of a size sufficient to fit into a standard 201b lpg cylinder 18. In one form shown in fig. 1 and 2, the base 12 has an upper shroud portion 12a, the upper shroud portion 12a being of High Density Polyethylene (HDPE) material with the interior 16 cut away to snugly fit a liquefied petroleum gas cylinder 18 within the base 12. A lower support flange 13 of steel material, such as 11 gauge steel, having a wall thickness of about 0.250 inch may be provided at the bottom of the upper plastic portion 12a of the base 12. As shown, the diameter of the base support flange 13 is larger than the upper plastic portion 12a of the base 12, and the base support flange 13 supports the bottom of the can 18 in the base interior 16. If the tank 18 is a standard 201b lpg cylinder, the flange 13 at its bottom has a diameter of about 20.60 inches and a height of about 2.50 inches.

The support column 14 is preferably hollow so that a gas line 20 may extend upwardly through the tank 18 to a burner assembly 22 housed in a housing 24, as shown in fig. 3. The heating apparatus 10 may also be connected to an underground gas line, such as that provided by a utility gas company, with the legs 14 anchored to the ground and the gas line 20 connected to an underground utility line, so that the base 12 housing the tank 18 is no longer required.

In the apparatus 10, as well as other high efficiency heating apparatus 65,94 and 200 described in greater detail below, a high efficiency system, generally designated 25, is included which maximizes the amount of heat emitted from the burner assembly housing 24 for a preselected area around the heating apparatus. The thermal efficiency system 25 minimizes heat loss or the occurrence of unnecessary areas of heating of existing patio heaters. In this manner, the amount of fuel consumed by the thermal efficiency system 25 to heat the area desired to be heated is minimized.

Referring more particularly to fig. 2 and 3, for the apparatus 10, there is shown an arrangement of cover portions 26, the cover portions 26 being integrally formed with the housing 24 of the burner assembly 22 or attached in overlying relation to the housing 24 of the burner assembly 22. The post 14, base 18, housing 24 and cover 26 are all aligned along a central vertical longitudinal axis 10a of the device 10. The cover 26 serves primarily to protect the burner assembly housing 24 from exposure to outdoor environments, such as rain, snow, etc., and also to reflect dispersed radiant heat emitted at the housing 24 back down around the stanchion 14 and base 18 of the device 10, and particularly around the vertical axis 10a of the device, as will be described in greater detail below. Unlike prior patio heaters that use large reflector domes, the heating apparatus 10 of the present invention may have a small cover 26 because the burner assembly housing 24 is configured to minimize the dissipation of heat therefrom.

More particularly, the thermal efficiency system 25 of the apparatus 10 comprises a radiant surface 28 of the casing 24 inclined with respect to the longitudinal axis 10a so as to face generally downwardly and to be radially outwardly; i.e. in the direction of the desired heated area 30 under the cover 26 about the axis 10 a. The radiant surface 28 has apertures 28a formed therein to allow hot gas products of combustion produced by the burner assembly 22 to exit the housing 24. Preferably, the radiant surface 28 is of a 18 gauge stainless steel material, so that the flow of hot gases through its apertures 28a sufficiently heats the surface 28 to generate radiant infrared heat emanating from the surface.

Since the radiant surface 28 is inclined so as to face in a generally downward and radially outward direction, heat emanating therefrom will also be directed in a generally downward and radially outward direction so as to heat the preselected region 30 about the longitudinal axis 10a of the device. The heating region 30 includes a primary region 30a which primarily receives its heat directly from the inclined radiating surface 28 and has a generally conical shape, i.e., forming a gradually widening radius down the axis 10a of the device, as shown by the dashed line in FIG. 2. In this regard, as previously discussed, existing commercially available patio heaters having vertically oriented cylindrical radiant surfaces generate heat radiating radially outward therefrom, and only a portion of the heat is reflected downwardly in a desired direction by the large dome reflectors thereon, the housing 24, and particularly the radiant surface 28 thereof, providing greater efficiency of the heating zone 30 than such existing patio heaters.

Although the cover 26 serves to reflect the dispersed radiant heat emitted by the housing 24, the cover 26 serves primarily to protect the housing 24 from the elements and is significantly smaller in size in the radial direction, particularly as compared to reflector domes used with existing patio heaters. In addition, since the cover 26 does not have direct concentrated radiant heat, the cover 26 shown in the best illustrated form may be spaced entirely vertically above the housing 24. In this regard, the cover 26 may also be longitudinally shorter in height than prior dome reflectors, as it need not extend downwardly to overlie the inclined radiating surface 28. Due to the small size of the cover 26, the device 10 is particularly suited for retail sale because it can be compactly packaged for installation in a retail shelf space and for installation into the trunk of a car after purchase.

Referring to fig. 3A, there is shown schematically the difference between the thermal efficiencies of a conventional patio heater and the patio heater 10 of the present invention having a sloped radiant surface 28. As shown, the concentration of radiant heat emitted from the housing of the conventional heater is shown by the dotted line, compared to the case of the heater 10 of the present invention in which more heat emitted from the housing 24 is concentrated in a small radius around the axis 10a, the radiant heat is shown by the solid line. The height at the interface of the housing 24 and the cover 26 is about 86 inches, whereas existing heaters are relatively high, such as about 92 inches, and the heater 10 of the present invention has been found to provide a greater focal range or concentration of heat in a small radius, such as about 2-3 feet, about the central vertical axis 10a of the device 10.

Further details of the structure of the illustrated device 10 will be described below. The burner assembly housing 24 may be connected at the top end 32 of the vertical support bar 14 to an inclined radiant surface 28, the radiant surface 28 being a flat smooth surface and being perforated with a plurality of holes 28 a. Surface 28 tapers upwardly and radially outwardly away from rod tip 32 such that it has a generally frustoconical shape. It is apparent that other shapes of the radiating surface 28 that direct heat generally downward and radially outward are within the scope of the invention, such as a curved radiating surface, e.g., forming a parabolic shape.

A short, non-apertured upper cylindrical wall portion 34 of the housing 24 projects upwardly from the top end of the surface 28. The cover 26 is secured to the housing cylindrical portion 34, as can be seen in FIG. 3. More particularly, the cover 26 is connected to the top of the cylindrical portion 34 at the bottom of an upwardly open generally concave or dish-shaped main central portion 36. At the radially outer end 36a of the cover part 36, a downward annular lip 38 is formed, which is, for example, an aluminum material. In a preferred form, with a cylindrical radiating surfaceUnlike prior patio heaters for large dome reflectors, the bottom 38a of the lip 38 is spaced vertically above the housing cylindrical portion 34 and does not have to overhang because the cover 26 does not have heat focused directly radially outward. In addition, the dimensions of the cover 26, particularly in the radial direction transverse to the longitudinal axis 10A of the device, can be greatly reduced, for example, by about 26 inches across the diameter of the bottom 38a of the cover lip 38, as compared to the prior art whereA dome reflector of inch diameter, while also extending radially sufficiently beyond the shell 24 to protect it from rain and snow.

As previously mentioned, one of the functions of the cover 26 is to have the ability to reflect stray radiant heat that is emitted from the housing 24 and thence downwardly back around the device 10 to heat the preselected area 30 below the cover 26. In this regard, the cover dished portion 36 preferably includes a smooth and flat inclined surface 40 on its underside. The inclined surface 40, which is similar to the housing surface 28, is inclined relative to the longitudinal axis 10a so that it faces in a generally downward and radially outward direction to reflect heat accordingly. In the illustrated form best shown in fig. 3, the slope of surface 40 relative to vertical axis 10a may be slightly less than the slope of surface 28. By way of example and not limitation, surface 28 may be inclined at an angle of about 70 degrees relative to axis 10a, while surface 40 is inclined at an angle of about 60 degrees relative to axis 10 a. The downward lip 38 also helps to capture and reflect radiant heat emitted from the housing 24, such as that which may be dissipated along the surface 40, and redirect that heat back down so that it radiates from the surface 40 into the area 30 to be heated, or from the lip 38 directly into the area 30 around the axis 10a, as schematically illustrated in fig. 3A.

It has been found that with the above-described construction of the housing 24 and the cover 26, the heating apparatus 10a maximizes the hot air coverage throughout the preselected area 30 below the cover 26 for efficient heating. In other words, substantially all of the heat generated by the burner assembly 22 and dissipated by the housing 24 is used to heat the zone 30 without any significant loss of heat radially outward from the cover 26, as is the case with the cylindrical open wall of existing commercially available patio heaters.

Preferably, the heating device 10 is detachable so that it can be stored and transported in a compact and cost-effective manner. Referring to fig. 4, a shipping container 44 is shown sized to accommodate all of the components of the heating apparatus 10. The device's strut or vertical bar 14 can be provided in two equal length bar sections 14a and 14b, with profiled pipe sections 46 at the ends of the sections 14a and 14b to form a mutual detachable connection. Furthermore, a releasable connection similar to the connection between the rod sections 14a and 14b may be provided at the top 32 of the post 14 between the post 14 and the housing 24, and also at the bottom 48 of the post 14 where it is tightly received within a central recess 50 at the top of the base 12.

The gas supply line 20 may be a flexible aluminum material, for example, in the form of an aluminum wire having a diameter of 3/8 inches and a wall thickness of 0.032 inches. Thus, it can be coiled within the cut interior 16 of the base 12. Thus, the base 12 is sized to receive a 20 pound lpg cylinder 18 which preferably will have a diameter of about 20.60 inches at the bottom of its support flange 13 as described above. In this form, the device 10 will preferably have a height of about 86 inches from the bottom to the interface of the housing 24 and the cover 26, and the outer diameter of the cover will preferably be less than the length of the coverFeet or about 26 inches. With respect to the above dimensions, the shipping container 24 may have dimensions of 27 inches by 36 inches, including a volume of 15.2 cubic feet, to accommodate all of the various components of the patio heater assembly 10 of the present invention, the patio heater assembly 10 including the base 12 with the gas lines 20 coiled therein, the leg sections 14a and 14b, and the housing 24 and cover 26 assembly. In this regard, the apparatus 10 of the present invention allows for the efficient use of very compact shipping containers, such as the container 44, to achieve significant savings in transportation costs and to reduce costs associated with the storage of the various components of the apparatus 10.

Returning to fig. 2 and 3, the burner assembly 22 and its control are described in more detail below. The control panel 52 is provided and includes an ignition actuator 54 and a gas valve control button 56 mounted thereon. The control panel 52 may be disposed within a cutout 58 formed in the upper corner of the base 12 so that the control panel 52 may be received in the slot. The burner head 60 is supplied gas from the fuel tank 18 through the gas line 20, the flow of which is regulated by the valve control 56. The igniter element 52, which is preferably of a piezoelectric type, ignites the gas when the pressure type ignition initiator 54 is pressed. A safety shut-off may be provided when controlled by a thermocouple 54 that is sensitive to temperature changes, which will cause an open gas valve (not shown) to close when the flame in the burner head 60 is extinguished for whatever reason after the gas valve control 56 is opened. In this manner, when no flame is present in the igniter 62, gas flow through the gas line 20 will be shut off to prevent dangerous build-up of unburned fuel gas in and around the housing 24.

Referring to fig. 5A and 5B, an alternative high efficiency heating apparatus 200 including a high efficiency system 25 is illustrated in exploded form to show the various components thereof, one of which is a radiation assembly 202 having a frustum-conical radiation screen 206 or grid 204 to provide an inclined radiation surface 206 having apertures 206a, the radiation surface 206 being similar to the inclined radiation surface 28 of the apparatus 10 previously described. In this regard, the apparatus 200 including the inclined radiating surface 206 provides an advantage of higher thermal efficiency than existing cylindrical radiating surfaces. As described with respect to the inclined apertured surface 28, the inclined surface 206 generally radiates heat in a downward and radially outward direction and directs the radiated heat into areas where heating is desired, while consuming minimal heat in areas where heating is not desired. To maximize coverage and thermal efficiency, the preferred slope of the surface 206 is 20 degrees relative to the vertical axis of the device 200.

In the apparatus 200, the large dome reflector 208 is utilized to reflect any stray radiant heat that may radiate upward from the radiant module 202. The reflector 208 is similar in size to the previously described prior art large dome reflector. The dome reflector 208 is primarily used to distinguish the device 200 from the retail oriented device 10 in that the device 200 is intended primarily for sale to commercial customers, directing radiant heat into the area to be heated within the slope of the radiant surface 206, while not requiring large reflector members. As best shown in fig. 5A, even if the reflector cap 208 does not radially overlap the emitter shield 204 to any significant extent, the problems of heat loss and thermal inefficiency created by the cylindrical emitter become less severe due to the slope of the surface 206.

Turning to further details of the construction of the apparatus 200, the radiant assembly 202 includes an inner conical member 210 of insulating material which is encased in an outer radiant grid 204 and contains the flame generated from a burner head 213 of an inlet valve housing 214. More specifically, the burner head 212 is attached to the bottom of the inner conical member 210 such that the circumferential ports 212a of the burner head 212 are generally aligned with the angled annulus formed between the radiating mesh 204 and the inner conical member 210. The radiator base member 216 is secured between the bottom of the open mesh 204 and the valve housing 214. The neck 218 of the burner head 212 extends through the radiator base piece 216 and connects to the top of a gas valve unit 220 disposed within the cylindrical valve housing 214. In this way, the insulated conical member 210 contains the flame formed by the burner head port 212a in the annular space between the mesh 204 and the inner insulated cone 210, which thereby blows down into the valve housing 214 and heats the valve unit 220.

To minimize the effects of wind and reduce the pressure build-up inside the radiation assembly 202, the radiator bottom piece 216 can be provided with a plurality of discharge ports 222, the discharge ports 222 being circumferentially dispersed over different portions of the piece 216, as can be seen in fig. 5A. In the preferred and illustrated form, the intermediate cylindrical portion 224 has a majority of the discharge openings 222 formed therein, and preferably 25 such discharge openings 222 are uniformly spaced circumferentially. The vents 222 help stabilize the device 200 against tipping in high wind conditions and prevent the indication and burner head flame from blowing out. Moreover, the pressure built up inside the radiant assembly 202 can be released through the vent 222 to reduce the tendency of a flame to pull into the valve housing 214.

Referring again to fig. 5, the gas supply line 226 passes through the strut 228 and is connected at the top to the bottom of the valve unit 220 by a corresponding fitting. The bottom of the gas line 226 is connected to the top of the regulator hose assembly 230 by a quick disconnect fitting. The regulator 234 of the assembly 230 is adapted to be valved on top of a lpg cylinder (not shown) which rests on a bottom flange 236 and is secured thereto by a restraining chain 238 which hooks over upstanding base legs 240 and 242 and is connected to a third leg 244.

A large cylindrical shroud 246 is sized to rest on the top surface of base flange 236 and fit over the cylinder around and between legs 240 and 244. The shroud 246 is perforated for air flow therethrough. The shroud 246 also has an opening 248 at its upper end to provide access to the valve in the drum without lifting the shroud 246 over the drum to turn the heater on and off as in prior patio heaters.

Platform 250 is mounted on the cross-section of the top end of legs 240 and 244 and has a mounting collar 252 thereon. A cap 254 closes the top of the shroud 246 and has a central aperture 256 through which the sleeve 252 projects to receive the bottom end of the post 228 inserted therein. When the post 228 is placed on the platform 250, a screw (not shown) threaded on the sleeve 252 may be threaded to secure the post 228 therein.

Fig. 6-9 show another high efficiency heating apparatus 65, particularly where the upper portion 66 employs the aforementioned large reflector cap 68, which reflector cap 68 is dome-shaped curved such that it opens downwardly around a burner assembly housing 70 having an apertured cylindrical radiant surface 72. As previously mentioned, the use of a large reflector cap 68 results in heat loss and a significant inefficiency in the amount of fuel required to heat a given area, with the lower edge 74 of the large reflector cap 68 nearly aligned with the midpoint of the radiating surface 72. Furthermore, much of the time is not required for heating around the entire 360 degree circumference of the post 74, such as when the device 65 is near a corner, and thus it is difficult for a person to stand around the entire device 65. Accordingly, the thermal efficiency system 25 of the apparatus 65 includes a heating zone adjuster 78 associated with the dome reflector hood 68 and the housing 70, which is adjustable to reflect heat emitted by the housing to change the preselected area heated about the post 74.

More particularly, the heating zone adjuster 78 may take the form of a heat diverter or movable baffle adjustment mechanism 80 that is mounted adjacent the housing wall 72 and is adjustable to block heat emanating from a portion 82 of the bottom or lower face 76 of the reflector hood 68. Referring to fig. 6-8, the diverter 80 can be adjusted to a number of different positions to change the size of the reflector portion 82 on the underside 76 of the cover 68 and, thus, block the heat emitted by the housing 70, thus, changing the preselected area to be heated by the heating device. In this regard, the heat diverter or moveable reflective plate adjustment mechanism 80 is movable between a first position and a second position, with substantially the entire extent of the lower face 76 of the cover 68 serving to reflect heat emitted by the housing when the mechanism 80 is in the first position (FIG. 7) so as to heat the entire 360 degree circumference around the post 74 below the cover 68. To change the heating zone, the mechanism 80 is moved to its second position (fig. 8 and 9) such that a portion of the entire 360 degree circumference on the lower face 76 of the reflector hood 68 is used to reflect the heated air emitted by the housing 72, thereby heating less than 360 degrees of the area around the post 74 below the hood 68.

As shown, the movable reflection plate adjustment mechanism 80 may include a pair of rotatable reflection plate members 84 and 86, and one end of the rotatable reflection plate members 84 and 86 is rotatably connected to a rotation shaft 88. The rotating shaft 88 is supported on a platform extension 90, the platform extension 90 protruding radially from near the bottom of the burner assembly housing 70, and the top end of the rotating shaft 88 is connected with the bottom surface 76 of the reflector cap 68, as shown in fig. 6.

The reflector members 84 and 86 may be generally triangular in shape with the upper and lower sides thereof slightly curved outwardly. As shown in fig. 6, the curvature of the top surface 92 matches the curvature of the lower face 76 of the reflector cap 68, and thus, heat generally does not rise up and over the reflector plate, but rather approaches the blocking surface portion 82 of the cap 68 and is reflected downwardly therefrom. The bottom sides of the triangular reflection plates 84 and 86 are rotatably connected at a rotation shaft 88 so that the reflection plates 84 and 86 are rotated therearound.

To adjust the area heated by the heat emitted by the radiant surface 72, the reflective plates 84 and 86 may be rotated open about the axis of rotation 88 to change the size of the portion 82 of the reflective surface 76 of the hood 68 to divert heat therefrom through the reflective plates 84 and 86, the reflective plates 84 and 86 in turn adjusting the area under the hood 68 that is not heated to the same extent as the other heated areas, bearing in mind that some heat may flow to areas that are not heated, for example, due to wind or other forces. Regardless, in general, it is the fact that the area under the rotatably openable reflective plates 84 and 86 and under the surface portion 82 of the reflector cap 68 does not heat up to the same extent as the area under the rest of the cap 68.

The reflective plates 84 and 86 may be held in their rotated open position by friction of the reflective plates 84 and 86 being rotatably mounted to the shaft 88, or by frictional engagement of the curved top surfaces 92 of the reflective plates 84 and 86 with the hood lower face 76, or by any other suitable means. Thus, rotating the reflector plate members 84 and 86 allows for the use of substantially the entire 360 degree extent of the bottom surface 76 of the reflector cap 68, as shown in FIG. 7, to reflect heat emitted from the housing 70, or, as shown in FIG. 9, during operation of the device 65, the rotating reflective plate members 84 and 86 may be rotated to and maintained in their fully open positions, where the reflective plates 84 and 86 are aligned with each other, such that the surface portion 82 is spaced from the heat emitted from the housing 70, only the remaining portion of the surface 76, excluding the dam portion 82, is therefore used to reflect heat from the housing 70, or, in various positions therebetween, such as shown in fig. 8, during operation of the device 65, the reflective plates 84 and 86 are rotated into perpendicular relation to one another and held there, the blocking surface portion 82 is therefore smaller than the blocking surface portion 82 when the reflective plates 84 and 86 are rotated to be bent open as shown in fig. 9. Accordingly, the reflective plate members 84 and 86 can be adjusted to a plurality of different positions to vary the size of the reflector surface portion 82, the reflective surface portion 82 being spaced from the heat, thereby allowing adjustment of the preselected area to be heated by the device 65 so that only the area where one can gather around the device 65 is heated and therefore heat is not directed to inaccessible areas around the device 65, thereby saving heat and fuel.

Fig. 10A and 10B illustrate another high efficiency heating apparatus 94. And in particular the upper housing assembly 96 thereof, includes a housing 98 containing a burner head similar to the burner head 60 described above for igniting fuel provided by a fuel source, such as the tank 18 of liquefied petroleum gas. The housing 98 is substantially identical to the housing 70, and the housing 70 is typically provided with the large dome-shaped reflector cap 68 described above. In the heating device 94 with the large reflector cap 68 removed, at least one wall panel 100 is provided to reflect heat emitted from the burner assembly housing 96.

More specifically, the housing assembly 96 may include a cylindrical wall portion 102 disposed between tapered top and bottom cover portions 104 and 106, the wall portion 102 being apertured to provide an apertured cylindrical radiating surface 108 similar to the apertured radiating surface 72 previously described. The hot air generated by combustion within housing 98 exits through apertures 108a and is directed generally radially outwardly due to the vertical circumferential orientation of surfaces 108. In this regard, the wall plate 100 is configured to direct heat expelled from the aperture 108a and infrared heat emanating from the housing wall 102 in a generally downward direction about the longitudinal axis 94a of the device 94. The advantage of using the wall plate 100 compared to existing reflector hoods is its greatly reduced size and adjustability, so that the area to be heated can be easily changed according to the needs of the user.

More specifically, wall plate 100 includes a proximal portion 110, an annular body portion 112, and a distal bend 114. Wall plate 100 is adjustably connected to housing 98 at proximal end 110, such as by surface clips or any other suitable fastening mechanism, allowing the position of wall plate 100 to be easily adjusted relative to central axis 94a and then fixed in place. As shown, proximal portion 110 may extend radially outward and downward, with annular body portion 112 also sloping radially outward and downward, however, the angle of substantially larger body portion 112 relative to vertical axis 94a is less than the corresponding angle of proximal portion 110, and thus, the body portion extends radially outward a greater distance than the corresponding distance of the proximal portion. At the radially outer end of body portion 112, distal portion 114 is bent downwardly at a greater angle relative to axis 94a than body portion 112, such as at a similar angle to proximal portion 110, and extends to distal end 114a of wall plate 100.

As shown in fig. 10B, preferably a plurality of wall panels 100, such as vertically spaced wall panels 100a,100B and 100c, are adjustably spaced about housing 98 to allow for variation in spacing B between adjacent wall panels 100a-100 c. In addition, the large number of wall plates 100 also minimizes the risk of accidental contact with the hot circumferential wall 102 of the housing 98.

As previously mentioned, one particular advantage of using wall plate 100 is its small size. In particular, it is preferred that the maximum distance R from the central axis 94a to the distal end 114a of the wall 100 be less than the radius of the base 12, such as 10.3 inches when sized to fit into a standard sized LPG tank 18. In this manner, wall panel 100 may be removed from housing 98 and loaded into base 12 for storage and shipping.

In addition, as previously described, the adjustability of wall panel 100 allows its lower heating zone to be varied according to the needs of the user. For example, in locations where there are few people around the device 94, heating of a smaller radius around the axis 94a can be readily achieved by adjusting the wall plate 100 downward to reduce its effective radius R from the central axis 94a, as shown in the cut-away portion of FIG. 10A. On the other hand, where there is a large concentration of people around the device 94, the wall 100 can be adjusted back toward its maximum radius R to increase the radius of the area around the device axis 94a, which is heated by the heat emitted from the housing 98.

The adjustability of wall plate 100 also provides greater flexibility in determining the optimum spacing between adjacent wall plates 100a-c as a function of the size of the wall plates, and in particular the size of main body portion 112 and distal end portion 114. In the preferred form shown in fig. 10B, three equally spaced wall panels 100a-100C are used, with the radius of the annular portion 112 of the wall panel 100 being about twice the distance B between adjacent wall panels 100a-100C and about four times the radius of the distal bend 114 of the wall panel 100C. In addition, the body portion 112 is inclined at about 120 degrees relative to the vertical axis 94a, and the wall plates 100a-100c are shaped to include an included angle of 150 degrees between the annular body portion 112 and the distal bend 114.

The use of the wall panel 100 may provide advantages in heating efficiency and safety as compared to existing reflector hoods used in cylindrical burner assembly housings 98. As mentioned previously, existing reflector hoods for use with cylindrical radiating surfaces are deficient because not all of the radially outwardly emitted heat is reflected by the hood, and as such, there is a loss of heat, resulting in inefficient heating of the desired area around the heating device and below the hood. This inefficiency therefore results in an increase in the amount of fuel necessary to heat the area being heated by the device. On the other hand, as shown in fig. 10A and 10B, the wall plate 100 substantially minimizes or eliminates any radiant heat emitted by the cylindrical radiant surface 108 that does not encounter the wall plate 100, so that substantially all of the heat emitted by the housing 98 is reflected by the wall plate 100 to heat the desired area around the device 94. In this manner, wall panel 100 provides improved heating efficiency because less fuel is consumed to heat a preselected area around device 94 than is necessary when using a reflector cap.

Fig. 11-13 illustrate other modifications that may be employed in the foregoing heating apparatuses 10,65 and 94. Fig. 11 shows a heating device 116 having a base 118 containing a fuel tank and a leg 120 projecting upwardly therefrom into a burner assembly housing 122, a reflector hood 124 being connected to the housing 122 to reflect heat downwardly as previously described.

A modification of the heating device 116 is to provide a table 126 having a central through opening 128 to receive the post 120 therein. In this regard, the table top 130 is disposed on the base 118, while the post 120 extends through the opening 128. The collapsible legs 132 of the tabletop 126 are pivoted outward from under the tabletop top 130 to provide a stable tabletop 126 in use. The legs 132 may be sized to match the size of the base 118 so that the table top 130 abuts or engages the top of the base 118. Alternatively, the legs 132 may be omitted from the table top 126 and the entire weight of the table top 130 dropped onto the base 118, as can be seen in FIG. 12. To protect people sitting around the counter top 126 from rain or sunlight during the day, an umbrella 134 is mounted on top of the device by a mat mount 136 attached to the top of the reflector hood 134. As illustrated, the umbrella 134 may be relatively large, such that it includes the reflector hood 124 and extends radially beyond the tabletop top 130.

To enhance the function of the aforementioned fuel efficiency system 25, a motion sensor 38 may be provided to control the ignition of fuel by the burner assembly. The sensor 138 detects movement of a person around the device so that the burner assembly does not ignite the fuel if no person is present, and thus does not waste fuel for heating when not needed. Similarly, when the motion sensor 138 detects the presence of a person based on the person's motion, the sensor 138 will ignite the fuel through the burner assembly to heat the surrounding equipment and the person.

As shown in the apparatus 116, the motion sensor 138 may be disposed within an enlarged lower valve housing extension 140 of the burner assembly housing 132 between the burner assembly housing 132 and the top of the strut 120. More specifically, the extension 140 has a bottom frustoconical section 142 connected to the top of the strut 120, the bottom frustoconical section 142 tapering down from a main section 144 of the valve housing extension 140 to the top of the stem 120 and provided with a window 146 for a sensor element 148, as best shown in FIG. 13. The motion sensor 138 and its sensing elements 148 may comprise an infrared or sonar type motion sensor that transmits an infrared beam or sound wave, respectively, which when interrupted causes a change in the state of the sensor circuit, thereby indicating motion, as is well known. Other means for sensing motion and controlling ignition may also be used within the scope of the present invention.

As mentioned previously, patio heaters are often used in hotels and bars where customers must go outside to draw smoke due to smoking ban. As indicated, these heaters are primarily intended for outdoor use at night. Therefore, lighting around patio heaters is a major concern. In this regard, as shown in fig. 11 and 12, a lamp, such as a gas lamp 150, may be used in conjunction with the heating device 116. As shown, the gas lamp 150 may be mounted at various locations on the device 116, such as between the housing 122 and the reflector 124, and is preferably fueled by the same fuel source that supplies fuel to the burner assembly to illuminate the area surrounding the device 116 to be heated. In this manner, customers standing around the device 116 are in a well-lit and comfortable-temperature area just as they are indoors.

The gas lamp 150 may alternatively be positioned along the support post 120 when the gas lamp 150 is mounted below the cover 124 such that the temperature is too high. As shown in fig. 11, the reflector 151 is disposed on the lamp 150 at a position where the lamp 150 is mounted on the support post 120, and thus, heat emitted from the lamp 150 is substantially blocked, thereby not increasing the temperature of the valve unit in the housing extension 140 mounted thereon. Alternatively, as shown in fig. 12, the reflector 151 need not be provided at a position where the arm 153 of the gas lamp 150 extends from the support column 120.

Referring to fig. 13, the contact switch 152 comprises, for example, the form of a mercury switch that is perceptible when the device 116 is tilted a predetermined amount. When this tilt condition is detected, the switch 152 interrupts the signal from the thermocouple that keeps the gas valve open to shut off the device. Thus, if the device 116 should tip over and fall, the heater will not continue to ignite because tilting the mercury switch 152 closes the gas valve to shut off the device 116.

An additional advantage included in the described heating apparatus 10,65,94 or 200 is a fresnel glass lens housing 154 for the burner assembly housing or radiation assembly, the lens housing 154 having fresnel ridges 154a to radiate heat therefrom. In this manner, the problem of wind and pressure build-up within the aforementioned burner assembly housing of the apparatus 200 is significantly reduced, as the glass enclosure 154 serves to shield the housing or radiant assembly including the inclined radiant surface from the wind and does not affect the thermal efficiency of the apparatus.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made, and it is intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention.

Claims (24)

1. A heating device, comprising:

a burner assembly for igniting fuel from a fuel source;

an upper housing of the burner assembly, the housing having a central longitudinal axis extending therethrough; and

a thermal efficiency system that maximizes the amount of heat that can be dissipated from the housing and directed in a generally downward direction into a preselected area below the housing for heating the preselected area to minimize the amount of fuel necessary to heat the preselected area.

2. The heating apparatus of claim 1 wherein the thermal efficiency system includes a radiant surface of said housing having apertures for directing heat generated by the ignited fuel outwardly away from the housing, the radiant surface being inclined relative to the longitudinal axis to direct heat in a generally downward direction about the longitudinal axis to maximize the efficiency of the heat emitted from the housing for heating the preselected outdoor area.

3. The heating apparatus of claim 1 wherein the thermal efficiency system includes at least one wall plate extending perpendicular to the longitudinal axis and adjustably connected to the housing to allow the position of the wall plate to be varied relative to the axis to direct heat emanating from the housing in a generally downward direction about the longitudinal axis.

4. The heating apparatus of claim 1 wherein the thermal efficiency system includes a heat reflector cap radially larger than the housing and disposed on the housing wall for directing heated air rising upwardly from the housing downwardly to heat a preselected area below the cap; and

a heating zone adjuster disposed under the cover and adjustable to refract heat to alter a preselected region heated by heat emitted from the housing.

5. A heating device, comprising:

a burner assembly for igniting fuel from a fuel source;

an upper housing of the burner assembly, the housing having a central longitudinal axis extending therethrough; and

a radiating surface of the housing having apertures for directing heat generated by the ignited fuel outwardly away from the housing, the radiating surface being inclined relative to the longitudinal axis so as to direct heat in a substantially downward direction about the longitudinal axis, thereby maximizing the efficiency with which heat emitted by the housing heats the preselected area.

6. The heating apparatus of claim 5 including a cover on the housing, the cover extending radially outwardly of the housing to protect the housing from exposure to rainfall, the cover being spaced along the longitudinal axis on the radiant surface to reflect back around the longitudinal axis in a downward direction the dispersed radiant heat rising above the housing.

7. The heating device of claim 6, wherein the heating device comprises an elongated support member projecting upwardly along the longitudinal axis into the burner assembly housing; and is

The cap member has a predetermined diameter perpendicular to the longitudinal axis, the diameter having a length less than aboutFeet to provide stability against toppling.

8. The heating device of claim 7, wherein the heating device includes a base of sufficient size to receive a fuel tank, the burner assembly housing being substantially smaller than the base, the elongated support extending along the longitudinal axis between the base and the housing; and is

Separable connection mechanisms are provided between the support, base and housing to allow for compact transportation and storage.

9. The heating apparatus of claim 5 wherein the radiating surface is flat and inclined at a predetermined angle relative to the longitudinal axis to direct heat downwardly and radially outwardly from the longitudinal axis.

10. The heating device of claim 9, wherein the predetermined angle is about 70 degrees to maximize hot air coverage throughout the preselected area.

11. The heating apparatus of claim 5 wherein the radiation surface has a frustum conical shape to direct heat downwardly and radially outwardly from the longitudinal axis, the housing further comprising an upper cylindrical wall portion projecting upwardly from the top of the frustum conical radiation surface.

12. The heating device of claim 5, wherein the heating device includes a motion sensor that controls ignition of the fuel by the burner assembly to generate heat when the sensor detects motion.

13. The heating device of claim 5, wherein the heating device includes a light associated therewith to illuminate a preselected outdoor area.

14. An upper housing assembly for a heating device, the upper housing assembly containing a burner head for igniting fuel supplied by a fuel source, the housing assembly comprising:

a cylindrical wall portion having a central longitudinal axis extending therethrough;

holes in the cylindrical wall for emitting hot gases generated by the burning fuel; and

at least one wall plate extending perpendicular to the longitudinal axis and adjustably connected to the housing wall to allow the position of the wall plate to be varied relative to the axis to direct heat emanating from the wall and the aperture in a generally downward direction.

15. The housing assembly of claim 14 further comprising a base for receiving a fuel tank, the base having a predetermined radius, and wherein the wall extends from the wall to a distal end thereof, the distance from the central axis to the distal end of the wall being less than the base radius, whereby the wall is of sufficient size to fit within the base for shipping.

16. The housing assembly of claim 14 wherein the at least one wall panel comprises a plurality of wall panels adjustable relative to one another to vary the spacing between adjacent wall panels and minimize the risk of accidental contact with the hot wall of the housing assembly.

17. The housing assembly of claim 14 wherein the wall plate has an annular body portion that is downwardly inclined relative to the central axis, and a bight portion spaced from the wall portion, the wall portion being downwardly inclined relative to the annular body portion.

18. The housing assembly of claim 17 wherein the at least one wall panel comprises a plurality of wall panels adjustable relative to one another to vary the spacing between adjacent wall panels; and is

The wall plate ring body and the bend have a predetermined radial length, the radial length of the ring body being about twice the spacing of adjacent wall plates and about four times the radial length of the bend.

19. The housing assembly of claim 14 further comprising a seat for receiving a fuel tank; an elongated support member extending generally along the longitudinal axis of the housing between and generally aligned with the base and the burner head; and a gas supply line arranged in the support for supplying gas from the fuel tank in the base to the burner head.

20. A heating device for controllably heating different areas around a heating device, the heating device comprising:

a burner assembly for igniting fuel from a fuel source;

a burner assembly housing having an apertured wall extending around the burner assembly for dissipating heat from the housing;

a heat reflector shroud radially larger than the housing and disposed over the housing wall to direct heated air rising upwardly from the housing downwardly to heat a preselected area under the shroud; and

a heating zone adjuster positioned below the cover and adjustable to refract heat to alter a preselected region heated by heat emitted by the housing.

21. The heating apparatus of claim 20 wherein the heating zone adjuster includes a baffle adjustment mechanism adjacent the housing wall, the baffle adjustment mechanism being movable between a first position and a second position, the baffle adjustment mechanism in the first position utilizing substantially the entire area of the reflector hood to direct heated air emitted from the housing to heat the preselected zone, and the baffle adjustment mechanism in the second position utilizing a portion of the substantially entire area of the reflector hood to direct heated air emitted from the housing to heat a different preselected zone.

22. The heating apparatus of claim 21, wherein the movable baffle adjustment mechanism comprises a rotatable baffle that is rotatably closed in a first position and rotatably opened in a second position.

23. The heating device of claim 20, including an elongated support for the housing, the support extending along a longitudinal axis, the apertured housing wall being aligned with the longitudinal axis; and is

The heating zone adjuster includes a heat diverter proximate the housing wall that is adjustable to block heat emitted by a portion of the reflector.

24. The heating apparatus of claim 23, wherein the heat diverter is adjustable to a plurality of different positions to vary the size of the reflector portion to impede heating to vary the preselected area of heating.