US 3388962 A
Description (OCR text may contain errors)
June 1968 R. s. BAUMANN ETAL 3,338,962
GAS APPLIANCE METERING DEVICE Filed July 7, 1966 Jar/aims 5. Eawnamr v X 16% United States Patent 3,388,962 GAS APPLIANCE METERING DEVICE Richard S. Baurnann, Glenbeulah, and Richard E. Linch,
Chilton, Wis., assignors to Western Industries, Inc., Milwaukee, Wis., a corporation of Wisconsin Filed July 7, 1966, Ser. No. 563,510 3 Claims. (Cl. 431344) ABSTRACT OF THE DISCLOSURE A portable pressurized gas fuel torch having a fuel metering device in the nature of a porous flow retarding element interposed in the fuel passage.
Background Portable pressurized gas fuel devices such as liquid propane torches are well known in the art. In these devices, it is important that a proper flame be maintained while the device is operating on a supply of pressurized liquid fuel. Especially in the operation of propane torches or the like, it is important to provide a flow and pressure regulating device since the appliance will only burn properly in an upright position, and flame sputtering and failure are encountered when the torch or other appliance is tilted or inverted.
It is customary to provide an adjustable needle valve or the like for establishing the proper torch or burner flame. Such adjustment of the flame is ordinarly made when the torch or burner and its attached pressure cylinder are in an upright position. However, these devices are not always used in such an upright position, and it is, of course, desirable that the flame adjustment should remain constant as initially adjusted regardless of the subsequent positioning of the device.
In order to accomplish continuity of flame adjustment, it is also common practice to provide a metering valve of one type or another between the pressurized cylinder and the needle valve adjustment in an effort to eliminate, or at least minimize, the possibility of an erratic or sputtering flame. Such metering valves are designed to perunit fuel passage under regulated pressure to the burner for maintaining an approximately constant flame, and without such metering valves, the tilting of the torch or other appliance or the partial emptying of the tank or fuel supply cylinder will cause the propane fuel to be brought in contact with the needle valve and permit passage of the fuel without becoming vaporized.
One type of metering or pressure regulating valve which has been heretofore proposed consists of a spring balanced device housed within the body of a stem interposed in the fuel line between the supply source and the needle valve. While such prior metering valves have enjoyed a certain degree of commercial success, they nevertheless consist of a considerable number of parts requiring careful assembly, thus adding to the complexity and cost of the device. Futhermore, these prior valves have not proven entirely satisfactory in the overall operation of the torch or other appliance due to their tendency to become unbalanced under certain conditions of operation, as when the attached fuel tank is only partially full.
Another type of metering valve or pressure regulating device which has been heretofore proposed for pressurized gas fuel torches and similar appliances consists of a relatively simple diaphragm interposed in the line between the fuel supply and the needle valve. These diaphragm type pressure regulators consist of a thin disc hav- 3,388,962 Patented June 18, 1968 ing metering apertures permitting passage of the pressurized fuel for maintaining the desired flame in all positions of operation of the appliance, the diaphragm being prestressed by forming the same with an annular detent seat so as to provide a valving action. Such diaphragm type pressure regulating valves have proven far less costly, less complicated and easier to assemble than previous metering valves embodying spring arrangements and the like, and they have proven highly effective in controlling and metering the desired amounts of fuel to the torch or burner with less likelihood of flame failure or erratic action upon tilting or inverting of the torch or partial emptying of the supply tank. However, these diaphragm valves do nevertheless require machine and stamping opertions as well as proper placement within a confined area and they are subject to fatigue through use.
Summary It is, therefore, an object of this invention to provide an improved device for properly metering pressurized gas fuel from a supply of the fuel to the burner of the gas appliance under regulated pressure and flow conditions while obviating all of the objections and disadvantages attendant prior devices intended for similar purposes.
Another object of the invention is to provide improvements in a liquid propane torch or the like which assures maintenance of the desired torch flame regardless of the position of the appliance and which also entirely eliminates the need for any working parts whatsoever in the pressure and/ or flow regulation thereof.
Another object of the invention is to provide an extremely simple and economical pressure regulator for pressurized gas conducted from a supply source or tank to the burner in constant amounts without regard for the position of the appliance in which the pressure regulator is incorporated.
A further object of the present invention is to provide a simplified fuel metering and pressure regulating device for a pressurized gas fuel torch or similar appliance which is entirely devoid of any moving parts whatsoever, which is readily positioned in the fuel line of the appliance, which requires no maintenance whatsoever and which is readily accessible for inspection and/ or replacement.
Still another object of the invention is to provide a gas metering device in the nature of a sintered metal pellet constructed of a material having a particular size and density such that liquefied propane gas may pass therethrough, the flow of the gas being retarded sufficiently so that the rate of progress through the filter or metering capsule is only as rapid as the rate of its use at the burner, thus permitting the appliance to operate at a constant predetermined and adjusted flame regardless of its posit-ion or fuel supply condition.
These and other more specific objects and advantages of the invention will be apparent from the following detailed description.
T he drawings A clear conception of the features constituting the present invention, and of the construction and operation of a typical commercial embodiment thereof, may be had by referring to the drawings accompanying and forming a part of this specification, wherein like reference characters designate the same or similar parts in the several views.
FIGURE 1 is an elevational view, partially in section, of a typical pressurized gas fuel torch embodying the invention;
I) :1 -0 3 FIGURE 2 is an enlarged fragmentary transverse section through the fuel torch of FlGURE l; and
FIGURE 3 is a perspective view in section of one of the improved gas metering filter capsules.
Detailed description Referring to the drawing, and particularly FIGURE 1 thereof, the pressurized gas fuel appliance shown therein as embodying the invention is a typical liquid propane designated generally by the reference numeral It The torcn it} comprises a cylinder 12 containing a supply of liquid fuel under pressure, a valve body 14 threaded to a cylindrical plug 16 carried by the cylinder 12, and a tubular neck or supply pipe 18 equipped at its end with a nozzle 26.
To adjust the flame emanating from the nozzle 20', an adjustment valve having a knob 22 is provided, the adjustment valve being located between the cylinder or supply tank 12 and the nozzle 20. This flame adjustment valve is shown as being in the form of a needle valve having a stem 24 threaded as at 26 into the valve body 14 whereby the flow of fuel from the supply tank 12 to the nozzle 20 may be regulated by adjusting the knob 22.
For example, by turning the knob 22 in one direction, the nose portion 28 of the needle valve will be seated against the seat 30 to close the passageway 32 and shut off the supply of fuel from the supply tank to the nozzle. By turning the knob 22 in the opposite direction, pressurized gas fuel will flow from the cylinder or supply tank 12 through the passageway 32 and into the burner tube 18 to the nozzle unit 20. The fiame issuing from the nozzle unit upon igniting the fuel issuing therefrom may then be adjusted by rotating the knob 22 to the desired extent.
Referring more particular to FIGURE 2 of the drawing, the valve body unit 14 is illustrated as being screw threaded upon the cylindrical plug 16, the plug 16 having a central bore 34 extending longitudinally therethrough. Bore 34 in the plug 16 is adapted to receive a valve unit 36 which is in the nature of the customary tire valve. This valve unit 36 is spring controlled so as to remain closed prior to insertion of the stem portion 38 of the valve body unit 14 within the bore 34 of the cylindrical plug 16 so that the pressurized fuel supply cylinder or tank may be sold or merchandized as a separate disposable unit. Upon insertion of the stem 38 of the valve body unit 14 within the bore 34 of the cylindrical plug 16, the tire valve 36 is opened to thereby allow pressurized gas fuel to flow from the cylinder 12.
In accordance with the present invention, the stem 38 is screw threaded as at 40 directly into the valve body unit 14, the stem 38 being provided with a passageway 42 extending longitudinally therethrough. The end of the assageway 42 of the stem 38 remote from the tire valve 36 terminates in an enlarged counterbore portion 44 and received within the counterbore 44 is a flow retarding or regulating element 46 having minute orifices. This flow regulating element 46 may be in the nature of a sintered metal pellet or equivalent structure having similar characteristics. The valve body 14 is accordingly formed with a fuel passage therethrough as defined by the passageways 32, 2, and the counterbore 44 thus forms a chamber intermediate the ends of the fuel passage 32, 42 within which the porous sintered metal pellet 46 is housed.
The sintered metal pellet 46 is formed of a material having a particle size and density such that the liquefied propane gas under pressure in the cylinder 12 may pass therethrough while being retarded sufficiently so that the rate of progression through the pellet is only as rapid as the rate of use at the burner nozzle 20. The sintered metal pellet 46, being porous, thus acts as a flow retarder .or regulator, and the rate of progression of the pressurized gas fuel through the element 46 is relatively constant and does not vary appreciably with the pressure applied to it. Thus the regulation of the How of the gas by the pellet insures that the liquid propane, after passing through the pellet is no longer subjected to high pressure since the rate of flow of the fuel into the chamber 44, void 48 and passageway 32 is the same as the rate of flow past the needle valve 23 and through the tube 18 to the burner nozzle 20. This lack of pressure together with the heat conductivity of the metal pellet 46 causes any liquid to immediately vaporize and allows operation of the appiiance in any position without the introduction of liquid fuel into the burner. The sintered metal pellet 46 is of a type which gives very close control over the flow rate therethrough and the provision of numerous microscopic orifices makes resultant plugging of all of the orifices highly unlikely thus providing a pressure regulating device which is entirely devoid of moving parts and which eliminates various machining and careful assembling operations.
It will, of course, be understood that the nozzle unit 20 may be of any conventional construction which provides for the passage of fuel through a central orifice 50 and which also permits entrance of atmospheric air through orifices 52, the nozzle being provided with a cylindrical shield 54 forming the combustion chamber. It should also be understood that suitable sealing means are provided for the stem portion 38 and the needle valve 28, and the design of the torch or other appliance may be varied without departing from the invention. Liquid propane torches provided with the improved flow or pressure regulating means have gone into actual commercial use and have met with considerable success. These devices have moreover reduced the cost of the torches or other appliances while improving the efficiency of operation thereof, and the pressure regulating devices forming the subject matter of the present invention are not subject to fatigue failure as are other devices intended for this purpose since there are no moving parts involved. It is intended that specific descriptive terminology used herein shall be given the broadest interpretation consistent with the disclosure, and various modifications within the scope of the invention may occur to persons skilled in the art to which the invention pertains. It should also be noted that in order to obtain the full benefit of the minute passageways in the flow regulating element 46, this ele ment is of cylindrical shape and has one end thereof entirely exposed to the fuel passage 42 with the other end thereof entirely exposed to the void 48 which is in direct communication with the fuel passage 32.
Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointed out and distinctly claiming the subject matter that is regarded as the invention:
1. A portable gas fuel device comprising, a container having a supply of pressurized fuel and provided with a discharge opening, a valve member secured within and normally closing said opening, a valve body receivable by said member and having a portion cooperable with said valve member to open the same, said valve body having a fuel passage therethrough communicable at one end with said container and provided with a chamber of enlarged cross-section intermediate the ends of said fuel passage, a burner nozzle communicating with the other end of said fuel passage, a porous metal flow retarding and heat conductive element housed within said chamber and spanning said passage, and valve means in said valve body adjustably manipulatable to open and close said fuel passage and meter the fiow of fuel passing therethrough, said valve means being disposed between said chamber and said burner nozzle and said tlow retarding element having one end entirely exposed to the fuel passage adjacent said container and the other end thereof entirely exposed to the fuel passage adjacent said valve means.
2. A portable gas fuel device according to claim 1, wherein the porous flow retarding element is formed of sintered metal having numerous microscopic orifices.
5 6 3. A portable gas fuel device according to claim 2, References Cited wherein the microscopic orifices are of a size and num- UNITED STATES PATENTS ber such that liquid propane gas entering the flow re- 2 666 480 1/1954 Peterson 158 33 tarding element is converted to gas and retarded sufii- 2:888:979 6/1959 Lindgren.
ciently so that the mass rate of flow of liquid into said 5 3 148 522 9/1964 Court element is approximately the same as the mass rate of y How of gas to the burner. JAMES W. WESTHAVER, Primary Examiner.