Patent Application
20100288268
The present invention relates to outdoor or patio heaters, normally gas-fired, known generally as parasol heaters, in particular to a parasol heater in which the parasol may be tilted.
Most parasol heaters available today comprise a generally cylindrical base which may be used as a housing for a bottle or cylinder of butane or propane gas, a shaft extending upwardly from the housing for supporting a gas burner element, and a heat reflective dish or parasol supported above the burner, designed to throw heat downwards in an area around the base. The gas burner element may alternatively be any radiant heat element, including an electric radiant element. The problem with this design is exemplified in the schematic of
By tilting the parasol at an angle to the burner, it is possible to reflect heat produced by the burner downwardly and to one side of the base. Therefore persons standing or seated to one side of the parasol heater would receive much more direct heat from the heater. The circular table over the base could more easily be replaced by different table configurations or seating arrangements in a restaurant or patio setting where the parasol heater is to be used.
DE-102004034148 (F. Polzer GmbH) describes a parasol heater with a tilting parasol dish, in which the dish is mounted on simple hinged mounting which is centrally disposed above the gas burner element. The parasol dish is only capable of tilting at an angle, about one axis. The disadvantage of this arrangement is that when tilted to an angle of about 30°, the underside of the parasol dish contacts the top of the gas burner which restricts any further tilting movement. This means that heat still cannot be reflected very far from the base and the region immediately surrounding the base. The hinge mounting could be spaced more above the top of the burner, to let the parasol dish clear the burner when tilted, but the problem with this is that it would have to be spaced by at distance corresponding to at least the radius of the dish, making such an arrangement impractical, because the underside of the parasol dish has to be kept as close as possible to the top of the gas burner to stop heat escaping upwards and to efficiently reflect it downwards.
Irish Patent No. S84796 describes an improvement to this arrangement whereby the parasol dish is connected to the radiant heat element by a mounting comprising a linkage which is adapted to allow the parasol dish to move in an arc over a side edge of the radiant heat element, whereby in use heat may be reflected therefrom in a parabola. As is evident from an inspection of
A mechanism provided on the same side of the burner 30 as the hinge mounting 50 is provided to cause the lower hinge bar 52 to rotate, which in turn causes the whole four point linkage to move to tilt the parasol dish 40 with respect to the gas burner 30. The lower hinge bar 51 carries a toothed gear 57 arranged to mesh with a worm gear 58 at the top of an operating rod handle 59. The user can twist the bottom of the handle 59, even when the gas burner is lit, to rotate the worm gear which causes the four point linkage to move and tilt the parasol dish to the desired angle. The gears 57, 58 provide a ratchet mechanism which resists further tilting of the dish unless the twist handle 59 is operated.
It is evident that the arrangement of S84796 advantageously allows for the focusing of heat generated by the burner at specific locations relative to the burner. However the mechanism by which the parasol dish is moved suffers from a number of disadvantages. Firstly, while it suggests that the user can twist the handle to move the parasol dish to a desired position even when the burner is lit, it has been found that the actuation of the worm gear linkage to effect any appreciable movement of the parasol requires an extended period of time. At all times during this actuation the user is very close to the burner and this can result in the user being exposed to too much heat for too long a time, thereby becoming very uncomfortable.
It has also been found that the use of the ratchet mechanism suffers in that on heating, the toothed gear 57 and worm gear 58 expand thereby restricting their relative movement to one another. This loss of smooth interaction can only be solved by turning the heater off and allowing it to cool sufficiently. In this way the ability to move the parasol heater during operation of the burner is reduced.
It will be further appreciated that such parasol heaters are intended for use in an outdoor environment. In such environments they become exposed to ambient conditions and unless the gearing mechanisms are fabricated from expensive rust resistant materials they can corrode or otherwise degrade through the exposure to inclement weather.
The present invention seeks to overcome the disadvantages with the prior art and to provide a parasol heater with a tilting parasol dish which reflects heat downwardly and to one side in the most efficient manner.
The present invention provides an improved parasol heater with a tilting parasol dish in accordance with the claims which follow.
In accordance with the teaching of the present invention, a parasol dish 40 is hingeably or pivotably coupled to a first side 600 of the burner 30 and the user effects movement by biasing the parasol from a second opposing side 610 of the burner 30. Similarly to the arrangement of
In contrast to the screw mechanism previously employed, in this arrangement movement of the dish is effected by direct movement of an actuator in the form of a handle 620 which is coupled to or engages with the dish 40. The handle is desirably pivotably coupled to the dish via a coupling arrangement 630 that allows for relative movement of the dish 40 and handle 620. In this way when the handle is biased upwardly by user action, movement of the handle will effect a corresponding movement of the dish 40. The handle 620 is desirably coupled to the dish at a location coincident with the coupling of the second set of couplings 606C, 606D. This serves to minimize the number of pivot points required as a first pivot pin 631 could be used for the coupling of components of the linkage 605 (which may not necessarily be a four point linkage) and the handle 620 to the dish 40.
It is evident that in this arrangement the actuator for causing the movement of the dish 40, in this exemplary arrangement a handle 620, is coupled directly to the dish 40 and is coupled above the burner 30. A portion of the handle 620 extends directly above the burner 30 and then extends downwardly along a side of the burner 30 to a distance sufficient to allow a user to the side of the heater to hold a grip portion 640 of the handle 620 to effect the movement. In contrast to the screw mechanism, in accordance with the present teaching, the handle is provided to the opposite side of the burner to the coupling mount 607 which connects the linkage to the burner 30.
So as to ensure that the handle does not project too far out from the longitudinal axis X-X′ of the heater, the handle is desirably not a straight handle but desirably is provided with at least a first arcuate portion 660 which is orientated to define a concave surface 661 proximal to the burner 30. In this way the handle bends towards the burner 30 at the first arcuate portion 660. The first arcuate portion is desirably provided at the handle at a position such that when the parasol dish 40 is in a non-elevated position—such as that shown in FIG. 7—the first arcuate portion 660 is coincident with an edge portion 741 of the burner 30.
To bring the grip portion 640 closer to the longitudinal axis X-X′ a second arcuate portion 670 may be provided on the handle such that the handle has first and second bends. The second arcuate portion 670 also desirably defines a concave surface 671 proximal to the heater such that the handle bends again towards the heater.
The handle desirably has a plurality of mating pins 701, 702, 703, 704 provided at defined locations along the length of the handle. The mating pins are provided to couple with a mating socket 710 which is provided at the opposite side of the burner 40 to the coupling mount 607. The mating socket defines a channel 711 within which mating pins may be received. On receipt therein, the mating pins engage with the socket and serve to maintain the handle at that position. As the handle is coupled to the dish 40, on engagement of the mating pins with the socket, the dish will also be supported and retained in its position. By providing a plurality of mating pins, the dish 40 may be moved between a plurality of defined positions relative to the burner. The number of pins employed and their relative spacing to one another may be used to determine the number of positions within which the dish may be moved. To move the dish from one position to another, the user moves the handle 620 to disengage the mating pin from its socket and then directs the handle upwardly or downwardly, as appropriate, to select another position.
The number of defined locations to which the dish may be retained is more limited than is achievable using a screw mechanism but this arrangement is advantageous in that it is more reliable than using the screw mechanism. It does not suffer from heat expansion and as such the dish may be moved during use of the heater. Any corrosion of parts does not affect the ability to move the dish. The handle provides a direct lever that allows for a pivoting of the dish about a fulcrum and this direct movement is particularly reliable. The present inventors have found that by providing a distinct number of coupling points between the handle and the heater that many of the practical locations where the parasol could be usefully located relative to the burner can be facilitated This range of angles is desirably such that at full tilt, the dish is disposed at an angle of about 30° to 90°, preferably about 45° to 60°, so as to reflect heat downwardly to one side, and preferably completely to one side, of the base 10 in a parabola, as seen in
The present invention is not limited to the four-point linkage embodiment described above. A three-point linkage, six-point or eight-point linkage or any combination of more than two linked hinges, sliding linkages, expandable or spring-loaded linkages and straight, curved or crank links is within the scope of the improved tilting mechanism for a parasol heater dish in accordance with the present invention, in which the tilting mechanism is adapted to move the whole parasol dish in an arc relative to the top of the radiant heater element, or top of the structure, both laterally over the top of the radiant heater element and downwards over a side edge of the radiant heater element, about more than one axis of rotation.
It will be understood that what has been described herein is a tilting mechanism that allows the parasol which is controlled by the mechanism to move downwards and to the side of the burner. In this way the burner may be maintained at a focal point of the dish. In an analogous art this can be compared to car headlights where a parabolic mirror is used in combination with a bulb to efficiently direct the light to a desired location. In the context of the present invention, the burner is located at the focal point of the parasol, such that heat that is generated by the burner is predominately directed in a preferred direction—as defined by the shape of the parasol. The tilting mechanism in more than one axis ensures that as the parasol dish is moved downwardly and to the side of the burner and that appropriate burner/dish distances are maintained to ensure that the heat is focused as required. As is evident from an examination of
It will be appreciated that what has been described herein are exemplary arrangements of a parasol heater that includes an actuator that allows a user to move the dish relative to a burner element of the heater, so as to allow for targeted heating around the heater. The actuator has been described in the context of a non-ratchet based arrangement that extends over and above the burner and also along a side of the burner to allow the user to grasp the actuator to drive the parasol dish to a desired location. It will be appreciated that modifications can be made to that described herein without departing from the spirit and or scope of the present invention and that the teaching is to be limited only insofar as is deemed necessary in the light of the appended claims which follow.
The words comprises/comprising when used in this specification are to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.
