FIRE PIT INCORPORATING SAFETY FEATURES

Abstract

A fire pit comprises a fuel source connector and at least one fuel outlet. A fuel conduit conveys fuel from the fuel source connector to the fuel outlet, and there is at least one sensor for detecting the presence of unburned fuel outside the fuel conduit. Further, the fire pit includes a fuel control mechanism for stopping or modulating the conveyance of fuel when the sensor detects the presence of unburned fuel.

Claims

1. A fire pit comprising: a fuel source connector; at least one fuel outlet; a fuel conduit for conveying fuel from the fuel source connector to the fuel outlet; at least one sensor for detecting the presence of unburned fuel outside the fuel conduit; and a fuel control mechanism for stopping or modulating the conveyance of fuel when the sensor detects the presence of unburned fuel.

2. A fire pit as claimed in claim 1 wherein the fuel source connector comprises a coupling valve connectable to a propane gas tank.

3. A fire pit as claimed in claim 1 wherein the fuel outlet comprises a plurality of apertures formed in a recessed receptacle.

4. A fire pit as claimed in claim 3 wherein the recessed receptacle accommodates lava rocks positioned therein to be heated by burning fuel discharging at the plurality of apertures.

5. A fire pit as claimed in claim 3 wherein the recessed receptacle comprises a generally circular shaped tray with the plurality of apertures located at or near a periphery thereof.

6. A fire pit as claimed in claim 1 wherein the at least one sensor comprises a first sensor positioned at or near the fuel source connector and at least one second sensor positioned at or near the fuel outlet.

7. A fire pit as claimed in claim 1 wherein the fuel control mechanism comprises a controller for receiving information from the at least one sensor, the controller being connected to the fuel source connector for effecting a stopping or modulating of the fuel flow from the fuel connector in programmed conditions.

8. A fire pit as claimed in claim 7 further comprising audio or visual alerts which are activated by the controller when one of the programmed conditions is detected.

9. A fire pit as claimed in claim 7 wherein the controller is connected to an external device for receiving or transmitting information from or to the fire pit and allowing control of the fire pit.

10. A fire pit as claimed in claim 1 wherein the sensor comprises at least one thermocouple for sensing temperature and transmitting temperature information to the fuel control mechanism.

11. A fire pit as claimed in claim 1 further comprising an ignition switch located at or near a fuel outlet for igniting the fuel.

12. A fire pit as claimed in claim 1 wherein the fuel source connector is connected to a propane gas tank and propane gas is the fuel for the fire pit.

13. A fire pit as claimed in claim 10 wherein the thermocouple is spaced from the fuel outlet by between about 10 mm and about 12 mm.

14. A fire pit as claimed in claim 1 wherein at least one of the sensors comprises a MQ9 sensor for detecting the presence of gases including one or more of carbon monoxide, benzene, alcohol, NOx, NH3, smoke or a combination of two or more of such gases.

15. A fire pit as claimed in claim 1 further comprising a housing having a space for accommodating a fuel supply tank, sensors, electronics and other components, and a wherein the fuel outlet comprises a recessed tray at an upper portion of the housing, the recessed tray accommodating the fuel outlet and heatable material therein.

16. A fire pit as claimed in claim 15 wherein the heatable material is comprised of lava rocks.

17. A heating device comprising: a fuel source connector; at least one fuel outlet; a fuel conduit for conveying fuel from the fuel source connector to the fuel outlet; at least one sensor for detecting the presence of unburned fuel outside the fuel conduit; and a fuel control mechanism for modulating the conveyance of fuel when the at least one sensor detects the presence of selected materials.

18. A heating device as claimed in claim 17 wherein the selected materials comprise one or more of carbon monoxide, benzene, alcohol, NOx, NH3, smoke or a combination of two or more of such gases.

19. A heating device as claimed in claim 17 wherein: the at least one sensor comprises a first sensor at or near the fuel source connector, a second sensor at or near the fuel outlet; and the fuel control mechanism comprises a controller receiving input from the first and second sensors, the controller being functionally connected to the fuel source connector so as to selectively modulate or cut off fuel supply to the fuel outlet in response to specified information received continuously in real time from the first and/or second sensors.

20. A heating device as claimed in claim 19 wherein the sensors are comprised of MQ9 sensors.

21. A heating device as claimed in claim 19 wherein the sensors are comprised of a thermocouple.

22. A method of making a fire pit comprising: providing a fuel source connector; providing at least one fuel outlet; connecting a fuel conduit for conveying fuel from the fuel source connector to the fuel outlet; locating at least one sensor for detecting the presence of unburned fuel outside the fuel conduit; and providing a fuel control mechanism for stopping or modulating the conveyance of fuel when the sensor detects the presence of selected materials.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In the drawings:

[0030] FIG. 1 is a top perspective view of a fire pit of the invention in one embodiment thereof;

[0031] FIG. 2 is a perspective view of the fire pit shown in FIG. 1 wherein the lava rocks are removed to show certain components and hardware of the fire pit;

[0032] FIG. 3 is a perspective view of a fire pit which has a propane gas cylinder as the fuel source, with the propane tank in the uninstalled position;

[0033] FIG. 4 is a view similar to that in FIG. 3 wherein the propane gas tank has been inserted and is connectable within the housing of the fire pit;

[0034] FIG. 5 is a further view showing in more detail the propane tank connected within the housing including the use of a conventional QCC connection device to the propane gas tank cylinder;

[0035] FIG. 6 is a schematic perspective view from the top of a fire pit of the invention, showing a detail section with the positioning of an ignition pin and a thermocouple; and

[0036] FIG. 7 is schematic flow chart and table showing safety features and structures associated with the controller used in a fire pit in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0037] Reference is now made to the accompanying drawings which shows a fire pit 10 in accordance with the present invention. Note that the invention is illustrated with reference to a fire pit but can be used in other appliances or devices where such systems may be necessary or desirable. The invention is therefore not one which is limited specifically to use on a fire pit.

[0038] In FIG. 1 of the drawings, there is shown a fire pit 10 having a housing 12 with a base 14, side walls 16 and a top 18. One of the side walls 16A has a door 20 which can be opened or closed to provide access to the interior space 26 of the housing 12. The top 18 has a circular recessed area 30 (which may have shapes other than circular) having a floor wall 32. In use, the recessed area 30 is filled with lava rocks 36 or some other similar type of material. The lava rocks 36 are heated as will be described and give character and effect as well heat to the fire pit 10.

[0039] FIG. 2 of the drawings is similar to that in FIG. 1, but the lava rocks 36 have been removed to better show the recessed area 30 and its components. In this recessed area 30, there is provided a thermocouple 38 or other type of temperature sensor for measuring the temperature and amount of heat at its location. The thermocouple 38 will relay information to a controller 42 (such as shown in FIG. 7 of the drawings) located within the housing 12 (or elsewhere), and the system will be programmed to react to information from the thermocouple 38 such as by shutting off gas supply when the heat exceeds a predetermined level.

[0040] FIG. 2 also illustrates the presence of an ignitor and gas flow control 44. There is an ignitor 48 which will spark upon activation which will in turn light the gas discharged from the gas flow control 44. Also seen is an auto ignition switch 100 which may be operated by pushing it, in turn activating the spark from the ignitor 48. The recessed area 32 will preferably have a plurality of gas holes 52 as seen in FIG. 6 of the drawings spaced around the circumference or periphery of the recessed area 30. Any configuration of gas holes 52 is possible in the invention and the invention is not limited to any one arrangement of such gas holes 52.

[0041] FIGS. 3 and 4 illustrate the insertion, or removal, process for a propane gas tank 60 in the interior space 26 of the housing 12. The door 20 is opened or removed depending on its form of attachment as seen in FIG. 3, and the gas cylinder 60 placed on a receiving portion 62 of the base 14 inside the housing 12. A QCC quick coupling valve 64 is then connected to the outlet of the gas cylinder 60 and tightened appropriately. The valve 64 attaches to a hose 66 at one end thereof, and the hose 66 at its other end connects to gas conduit piping 68 which conveys gas from the gas cylinder 60 to the gas holes 52 in the recessed area 30, as described above. When the gas is flowing and is discharged from the gas holes 52, the gas will be ignited and burn in the recessed area 30, providing heat and heating the lava rocks 36 located in the recessed area 30.

[0042] Once the gas cylinder 60 is installed and connected to the valve 64, the door 20 is closed or reconnected to close off the interior space 26 inside the housing 12.

[0043] FIG. 5 of the drawings illustrates the propane cylinder 60 installed inside the housing 12. This figure also illustrates the position of gas sensor MQ9 #1 70 which senses for the presence of unburned gas at and around the connection between the valve 64 and gas cylinder 60. As will be described, this gas sensor 70 communicates with the controller 42, and if gas from a leak is detected by the gas sensor 70, shut down or remedial action to prevent or reduce the effects of a dangerous condition are set in motion, thereby alleviating the or removing the condition.

[0044] FIG. 6 of the drawings shows the fire pit 10 of the invention in a top perspective view and a detail showing the position of the ignitor 48 and thermocouple 38. Also shown are the plurality of gas holes 52, through which gas from the gas cylinder 60 is discharged and ignited to create the heat for the fire pit 10 while burning. FIG. 6 also illustrates the gas sensor MQ9 #2 80, which is positioned at or near the ignitor 48 and in the region of the gas holes 52. The gas sensor 80 is able to detect the presence of unburned gas in the area that may be leaking from the gas holes 52 without being ignited, a potentially dangerous condition, since the build up of unburned gas is liable to explode and also, since it may near odorless and invisible, hazardous to those breathing the air in the vicinity of the fire pit.

[0045] FIG. 6 also shows one preferred embodiment where the distance between the thermocouple 38 and the gas hole is about 10 mm to about 12 mm. Note that this distance is not absolute, and can vary according to design and intended usage of the fire pit 10. Note, too, that there may be a plurality of gas sensors 80 arranged in a selected configuration at or near gas holes to have the capability of very local leak or unburned gas detection, adding safety to the system.

[0046] There may be additional sensors arranged in various locations between the gas connection to the propane tank and the discharge gas holes 52, in order to improve gas leak detection. Further, there may be sensors arranged around the fire pit in certain positions to detect the presence of unburned gas which may not necessarily have been detected or which are present along the gas feed line. Sensors outside the housing of the fire pit may be included in this embodiment.

[0047] FIG. 7 is a chart or table showing the electronics and operational steps of the safety systems built into the fire pit 10 of the invention. The controller 42 is programmed to control these features, and receives input from the gas sensors 70 and 80. The system may be shut down in response to signals from these sensors regarding the presence of unburned gas, when exceeding levels not considered to be safe.

[0048] The controller 42 also manages the indicator lights 84 for the fire pit 10 system. These may be red, green and blue, or another combination of different colors. The light illumination information and options are provided in the box 86, although these may vary based on model and level of sophistication which may be desired. Different lighting options provide information as to the charging status, system “in order” status, as well an option which indicates that there is a problem which has been detected and which requires either manual or automatic shut down to preserve safety in the region of the fire pit.

[0049] The controller 42 also monitors the valve 64 which may be opened and closed through the use of a switch 88 or other hardware. The controller 42 may also connect to the IOT at 90. Further, information as to temperature is received from the thermocouple 38 so that appropriate action can be taken when temperatures reach unacceptable levels which may create dangerous conditions.

[0050] The controller 42 may be powered by one or a combination of sources, such as a battery 92 which can be powered from several different sources.

[0051] The system may include an auto ignition switch 100 for use by the owner to generate a spark at the point of exit of the gas, at the gas holes 52, to initiate the burning of gas and heating process.

[0052] Note that the controller may also be programmed to send messages, such as through a Bluetooth connected device or through an internet Wi-Fi connection to a remote electronic device such as a smart phone to warn users or owners or others about the condition of the fire pit 10 when monitors detect a dangerous condition evolving.

[0053] Various input devices to the controller 42 are illustrated, including power bank, adapter, solar energy connector and USB plug or port.

[0054] According to one aspect of the invention, there is provided a fire pit comprising a housing, a source of gas, a burn recess area where gas is ignited and burned, and safety devices and monitors to monitor levels of heat and unburned gas.

[0055] Preferably, the burn recess area is filled or partially filled with lava rock or other heat retaining material.

[0056] The safety devices may include gas sensors. These gas sensors are preferably located at the point where a gas connection connects to a source of gas in the housing, and the point or points where gas is discharged into the burn recess area. A plurality of gas holes may be positioned in the burn recess area through which such gas is discharged. In one embodiment, the source of gas is a propane gas tank which is located in the housing and can be removed and replaced when the gas in the gas tank has been depleted.

[0057] The safety devices may further include a thermocouple, preferably place near gas holes, to monitor temperate and take appropriate action when temperature levels increase to undesirable or dangerous readings.

[0058] The fire pit of the invention further may comprise a controller for receiving information from the system including the safety devices, and which can take action in certain circumstances to mitigate danger, provide audible or visual warnings on conditions, or send messages to remote electronic devices to warn others who may not be in the vicinity of the fire pit that a hazardous situation is developing or has been reached.

[0059] Throughout this description, the embodiments and examples shown should be considered as exemplars, rather than limitations on the apparatus and procedures disclosed or claimed. Although many of the examples presented herein involve specific combinations of method acts or system elements, it should be understood that those acts and those elements may be combined in other ways to accomplish the same objectives. Acts, elements and features discussed only in connection with one embodiment are not intended to be excluded from a similar role in other embodiments.

[0060] As used herein, “plurality” means two or more. As used herein, a “set” of items may include one or more of such items. As used herein, whether in the written description or the claims, the terms “comprising”, “including”, “carrying”, “having”, “containing”, “involving”, and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of”, respectively, are closed or semi-closed transitional phrases with respect to claims. Use of ordinal terms such as “first”, “second”, “third”, etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements. As used herein, “and/or” means that the listed items are alternatives, but the alternatives also include any combination of the listed items.