US3741708A - Automatic gas torch - Google Patents

Abstract

This specification discloses an automatic gas torch comprising a cylindrical housing having a horizontal platform positioned in its upper end. A gas pipe extends upwardly through the housing and platform projecting above the latter. Included in the gas pipe is a valve operated by a bi-metallic element. The gas pipe is formed with a small lateral orifice above the platform and a burner having a plurality of lateral ports is mounted on the upper end of the pipe. A burner block is mounted on the platform in a radial position relative to the pipe and has a central passage that opens onto the orifice. It is also formed with openings on its side faces and top which communicate with the passage. Mounted on the platform adjacent to the burner block is an electric igniter and two thermo-operated switches on opposite sides of the block. One of these switches is included in the circuit of the bi-metallic element of the valve and the other in the circuit of the igniter. The first switch is normally open and the second, normally closed. When a main control switch is closed, the circuit to the igniter is completed and the igniter reaches a high temperature. The heat from the igniter is effective on the first thermo-switch to close it and complete the circuit through the bi-metallic element. As the latter heats to a required degree, the valve is opened and gas flows through the pipe. Some of this gas is emitted from the lateral orifice and enters the passage in the burner block and emerges from the openings in the block. Emerging gas from one opening is ignited by the igniter and the flame travels about the block to ignite the gas emerging from the other openings. The flame of one jet of gas heats the second thermo-switch to open it and interrupt the circuit to the igniter. The flame of the opposite jet heats the first thermo-switch to maintain the circuit to the bi-metallic element closed and the valve open. The flame from the top opening ignites the gas emerging from the burner ports.

Description

United States Patent [191 Bernstein AUTOMATIC GAS TORCH Primary Examiner-Edward G. Favors Attorney-Eric P. Schellin and John A. Robertson [57] ABSTRACT This specification discloses an automatic gas torch comprising a cylindrical housing having a horizontal platform positioned in its upper end. A gas pipe extends upwardly through the housing and platform projecting above the latter. Included in the gas pipe is a valve operated by a bi-metallic element. The gas pipe is formed with a small lateral orifice above the platform anda burner having a plurality of lateral ports is mounted on the upper end of the pipe. A burner block is mounted June 26, 1973 on the platform in a radial position relative to the pipe and has a central passage that opens onto the orifice. It is also formed with openings on its side faces and top which communicate with the passage.

Mounted on the platform adjacent to the burner block is an electric igniter and two thermo-operated switches on opposite sides of the block. One of these switches is included in the circuit of the bi-metallic element of the valve and the other in the circuit of the igniter. The first switch is normally open and the second, normally closed. When a main control switch is closed, the circuit to the igniter is completed and the igniter reaches a high temperature. The heat from the igniter is effective on the first thermo-switch to close it and complete the circuit through the bi-metallic element. As the latter heats to a required degree, the valve is opened and gas flows through the pipe. Some of this gas is emitted from the lateral orifice and enters the passage in the burner block and emerges from the openings in the block. Emerging gas from one opening is ignited by the igniter and the flame travels about the block to ignite the gas emerging from the other openings. The flame of one jet of gas heats the second thermo-switch to open it and interrupt the circuit to the igniter. The flame of vthe opposite jet heats the first thermo-switch to maintain the circuit to the bi-metallic element closed and the valve open. The flame from the top opening ignites the gas emerging from the burner ports.

6 Claims, 6 Drawing Figures Pmmmmm 3.7 41 708 SHEEP]. 0F 2 AUTOMATIC GAS TORCH The present invention relates to automatic gas torches and is concerned primarily with such a torch which is fully automatic and which is highly simplified as compared to prior art torches of the instant type.

BACKGROUND OF THE INVENTION Outdoor gas torches of the character with which the present invention is concerned are now being widely used. Examples of such torches are disclosed in the patents to Gieb, No. 3,038,064, Bernstein, No. 3,364,704, and Reese, No. 3,531,228. Of these, Bernstein is the most relevant to the subject torch in that it discloses automatic operation to a high degree and has many elements that are present in the present subject.

The patented Bernstein torch has a gas pipe including a solenoid operated valve. Such a valve opens and closes almost instantaneously when the circuit to the solenoid is closed or interrupted. This is satisfactory for opening of the valve, but is undesirable for closing, because power is often interrupted for short periods such as 5 or seconds. Such a short period of power failure will close the valve which is undesirable.

The Bernstein torch includes a spark plug and a transformer in addition to other elements, such as an electric heater and a pair of thermo-operated switches. It is highly desirable to eliminate the spark plug and transformer to the end of simplicity.

In a torch of the instant type, it is desirable that the igniter be in effect only during the initial stages of ignition. Once the flame of the main burner is started, the igniter should be de-energized. There is now an electric igniter that is made and sold by the Carborundum Co. of Niagara Falls, N.Y., that is particularly adapted for use in the subject torch.

OBJECTS OF THE INVENTION opening onto a lateral orifice in the gas pipe and three 4 openings communicating with the passage with each opening providing a jet flame having a distinct function.

4. To provide, in a torch of the kind described, a'gas pipe including a valve controlling the flame of gas and which valve is operated by a bi-metallic element through which an electric current is passed to open the valve. Closing of the valve is delayed a short period when the current through the bi-metallic element is discontinued.

5. To provide, in a torch of the type noted, a gas pipe includinga control valve that is electrically operated, a normally open thermo-switch controlling the circuit to the operating element of the valve, an electric igniter, and a normally closed thermo-switch controlling the circuit through the igniter.

Various other more detailed objects and advantages of the invention such as arise in connection with carrying out the above ideas in a practical embodiment, will, in part, become apparent and, in part, be hereafter stated as the description of the invention proceeds.

SUMMARY OF THE INVENTION The foregoing objects are achieved by providing an automatic gas torch comprising a vertical cylindrical housing having a horizontal platform at its upper end.

The platform is formed with a central opening and a gas pipe extends upwardly through the housing to the opening. A fitting is secured to the upper end of the pipe and projects above the platform. This fitting is formed with a lateral orifice spaced above the platform and a burner having lateral ports is attached to the upper end of the fitting. A valve operated by a bimetallic element is included in the gas pipe.

A burner block is positioned on the platform radially of the opening therein with an end thereof spaced from the lateral orifice in the fitting. The block is formed with a longitudinal passage that is closed at its outer end with its inner open end in cooperating relation to the orifice. The block presents a top surface and opposed side faces. Adjacent the closed end, the block is formed with three openings each of which communicates with the passage and one of said faces. These faces are formed with grooves or channels which connect the openings.

An electric resistance igniter is mounted on the platform in close proximity to one of the side faces of the block and opposite to the opening in that face. An electricv circuit is provided for the igniter. A first thermoswitch is mounted on the platform with its thermal component located on one side of the block. This switch is included in the circuit of the bi-metallic element and is normally open. A second thermo-switch is mounted on the platform on the other side of the block opposite to the opening in that side. The second thermoswitch is'included in the circuit of the igniter and is normally closed.

' A cover plate is mounted in the housing above'the platform and the above described elements carried thereby. This plate is formed with an aperture immediately over the opening in the top surface of the burner block.

A main control switch is provided and when this is closed the igniter is energized. As it heats the thermal component of the first thermo switch is heated to close that switch and complete the circuit through the bimetallic element. This causes the valve to open and gas flows through the gas pipe. Gas emerges from the lateral orifice in the fitting and enters the passage in the burner block. Gas is discharged as jets from the three openings in the block. The gas emitted from the opening in the side adjacent to the igniter is ignited thereby and the flame generated by this ignition travels along the channels in the block surfaces to ignite the gas emitted from the other two openings. The flame from the opening in the top surface passes through the aperture in the cover plate and ignites gas discharged from the lateral ports in the burner. The flame from the opening on the'side opposite to that on which the igniter is located heats the thermal component of the second thermo-switch to open this switch and break the circuit through the igniter.

For a full and more complete understanding of the invention, reference may be had to the following description and the accompanying drawings wherein:

FIG. 1 is a perspective of an automatic gas torch embodying the precepts of the present invention.

FIG. 2 is a perspective on an enlarged scale of the upper portion of the housing, the platform and the elements mounted on the platform;

FIG. 3 is a perspective depicting the several components of the subject torch in exploded relation;

FIG. 4 is a section through one of the thermoswitches;

FIG. 5 is a wiring diagram of the circuits including the bi-metallic valve, the igniter and the thermoswitches; and

FIG. 6 is a longitudinal vertical section through the burner block per se.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, a torch of this invention is identified generally by the reference character 10. It includes a cylindrical housing 1 1, which as shown in FIG. 3, is open at the top and has a bottom 12 formed with a central opening 13. At one side of the latter, bottom 12 carries a pair of spaced lugs 14 which preferably are integral with bottom 12. A small opening 15 is formed in bottom 12 in spaced relation to opening 13 and on the side of the latter opposite to lugs 14. Depending from bottom 12 is a tubular pedestal 16 which is used in mounting the torch on a support which ordinarily will be outdoors.

Still referring to FIG. 3, a gas pipe assembly is referred to in its entirety by the reference character 17. It includes a lower pipe section 18 which is threaded at its lower end for connection to a gas supply conduit. Its upper end is also threaded at 19. Pipe section 18 carries a tab 20 which is received between lugs 14 when gas pipe 17 is assembled in housing 11. The interfitting tab and lugs assure of proper angular relation between housing 11 and gas pipe assembly 17.

i A valve 21 is included in assembly 17. This valve controls the flow of gas through the pipe and is moved from open to closed position, and vice versa, by a bi-metallic element. The electrical leads for this element are indicated at 22. Inasmuch as bi-metallic devices of this type are well known and available to the public, further details of this phase of valve 21 are not illustrated or described. Valve 21 includes a nipple 23 on its lower side which is screwed onto threaded end 19 of pipe section 18 and another nipple 24 on its upper side. An upper pipe section 25 is connected to nipple 24. A fitting 26 is mounted on the upper end of pipe section 25. As shown in FIG. 2 fitting 26 is formed with a lateral orifree 27.

Still referring to FIG. 2, a burner 28 is mounted on the upper end of fitting 26 and has a cylindrical wall formed with lateral ports 29 and a closed top 30. A horizontal platform 31 has a depending peripheral flange 32 which snugly fits over the open top end of housing 11. It is also formed with an upstanding flange 33 of smaller diameter than flange 32. Platform 31 is formed with a central opening which receives fitting 26 with the latter projecting above the platform to locate orifice 27 above the platform.

A burner block is designated generally 34. It is mounted in a radial position on the upper face of platform 31 and presents a top face 35 and side faces 36, one of which shows in FIG. 2. Block 34 is formed with a longitudinal passage 37 having an open end in confronting relation to orifice 27. The other or outer end is closed, and communicating with passage 37 adjacent to its closed end are; an opening 38 in top surface 35, an opening 39 in one side face 36, and an opening 40 in the other side face. A channel 9 is formed in the top face 35 and side faces 36 to connect the openings 38, 39 and 40. Gas emerging from orifice 27 enters passage 37 and is emitted from openings 38, 39 and 40.

Upstanding from platform 31 is an igniter support 41, the upper end of which carries a spring clip 42. Clip 42 receives one end of igniter 43 which extends in spaced parallel relation with respect to the side face 36 of block 34 in which opening 39 is formed. Igniter 43 is substantially opposite to opening 39. lgniter 43 is an electric resistance element made and sold by the Carborundum Co. of Niagara Falls, N. Y. It is formed with a helIcal groove on its periphery as illustrated and the igniter which is used in the subject torch has a resistance of 200 ohms and when energized reaches a temperature of 2,800 F. When heated to a temperature in the neighborhood of the above maximum, it ignites gas that is emitted from the opening 39. It also serves the function of providing heat to the upper structure which is mounted on platform 31 during initial stages of operation of the torch. This is desirable because in many climates snow and ice will collect on the torch and the heat derived from igniter 43 is sufficient to melt such ice and snow and place the upper structure in condition for having the torch lit. The support 41 extends through and below platform 31 and its lower end is provided with leads 44 including the igniter in an electric circuit.

A first thermo-switch is identified in its entirety at 45. It is mounted in platform 31 and includes a thermal element 46 which extends above platform 31 in a position opposite to opening 39. Its lower end is provided with leads 47 for including it in the electric circuit through the bi-metallic element of valve 21. Thermo-switch is illustrated in more detail in FIG. 4. This switch is illustrated in FIG. 4 of the Bernstein Patent and described in detail therein. For the purposes of this speciflcation, it is sufficient to note that-this switch is normally open with the open condition provided by contacts 48 and 49 which are normally spaced. Contact 48 is carried by a thermal responsive element 50 which when heated to a required degree causes the contacts 48 and 49 to close and complete the circuit to the bimetallic valve.

A second thermo-switch 51 is mounted on platform 31 on the side of block 34 opposite to that on which thermo-switch 45 is mounted. Thermo-switch 51 includes a thermal element 52 which is located opposite to opening 40. Switch 51 is of substantially the same construction as switch 45 with the notable exception that it is normally closed. Thus, the contacts thereof which would correspond to the contacts 48 and 49 of switch 45 are normally in engagement, but are separated when the thermal responsive element corresponding to the element 50 is heated. Switch 51 is includes in the circuit through igniter 43.

The difierence in diameters between the flanges 32 and 33 provides an annular shoulder 53. A cylindrical windscreen 54 (FIG. 1) is fitted over flange 33 with its lower end in engagement with shoulder 53. Referring now again to FIG. 2, a strut 55 has its lower end anchored to the upper face of platform 31 whichmay be achieved by welding, as indicated at 56. The upper end of strut 55 is formed as a threaded stud 57 which is separated from the main body portion of strut 55 by an annular shoulder 58.

Referring now to FIG. 3, a cover plate 59 takes the form of a disc of a diameter greater than windscreen 54. It is formed with a central aperture 60 and concentric therewith is a collar 61 on the upper face of plate 59. It will be noted from FIG. 3 that burner 28 has a reduced neck 62 at its lower end which is externally threaded. This neck extends through aperture 60 and when the threads are tightened, plate 59 is clamped between fitting 26 and burner 28. Plate 59 is also formed with an opening 63 in which is fitted a short sleeve 64 that fits over strut 55. After plate 59 has been assembled on fitting 26 and strut 55, a nut (not illustrated) is screwed onto the screw stud 57 to secure the assembly, and in which position the plate 59 engages the upper end of windscreen 54 and extends therebeyond as illustrated in FIG. 1. A flame diffuser designated generally 65 includes an annular bottom plate 66 from which a conical peripheral flange 67 extends upwardly. Bottom plate 66 is formed with a large central opening 68 which fits about the burner 28 in spaced relation thereto and a recess 59 which opens onto opening 68. A portion of sleeve 64 extends above cover-plate 59 and is received in the recess 69. The flame diffuser 65 is assembled on cover plate 59 before the nut which is screwed onto screw stud 57 is applied thereto. Extending upwardly from the edge of hole 68 are a plurality of brackets 70 to the upper end of which is mounted dome-shaped member 71.

It is important to note that cover plate 59 is formed with an aperture 72 which, when the parts are assembled, is directly above the opening 38 in burner block 34.

Referring now to FIG. 5, a line 73 is-connected to a power source and included therein is a main control switch 74. Line 73 extends to a'terminal 75 to which one of. the leads 44 of the igniter is connected. The

other lead of igniter 44 is connected by line 76 to one of the contacts of the normally closed switch 51. Another line 77 extends from the other contact of the normally closed switch 51 to a terminal 78 which is grounded. Thus, when switch 74 is closed, the circuit through igniter 43 is completed.

This circuit remains completed until theigniter is heated to a required degree. When this occurs,switch 51 is opened, and the circuit to the igniter interrupted. However, before this takes place, the thermal element 46 of switch '45 is heated to a degree which closes switch 45. Thus, the circuit from thermal 75 by way of line 79, switch 45, and line 80. to the bi-metallic element of valve 21', is completed.

OPERATION ponent 46 of switch 45 is in close proximity to igniter 43, it is heated and after the elapse of a relatively short period of time is effective to close the normally opened switch 45. This completes the circuit through the bimetallic element of valve 21 to open this valve and permit the gas to flow through the gas pipe assembly 17. Gas emerging from orifice 27 enters passage 37 and is discharged through openings 38, 39 and 40. The gas jet from opening 39 is first ignited and the flame generated thereby passes along channel 9 to ignite the jets of gas emerging from openings 38 and 40. The flame jet from opening 38 passes through aperture 72 in cover plate 59 and ignites the gas which is discharged from the lateral ports 27 of burner 26. This provides the main flame of the torch'which is diffused by diffuser plate 65.

The flame jet from opening 40 is effective on the thermal component 52 of switch 51 to cause this switch to open and interrupt the circuit to the igniter. Thus, after the torch is lit, the igniter goes off.

Under some conditions, power is often interrupted for very short periods, such as those ranging up to 10 seconds. Should this condition arise, no current would flow through the bi-metallic element of valve 21 and this valve would start to close. However, the operation of the bi-metallic element is inherently a delayed one and the valve would not close until after the elapse of 10 seconds. Thus, the torch would remain in continuous operation even though the power should fail for short intervals.

While a preferred specific embodiment is herein disclosed, it is to be clearly understood that the invention is not to be limited to the exact constructions, mechanisms and devices illustrated and described because various modifications of these details may be provided in putting the invention into practice.

What is claimed is:

ll. In an automatic gas torch,

a. a vertical cylindrical housing;

b. a horizontal platform mounted on the upper end of said housing;

c. a gas pipe assembly extending through said housd. a valve in said assembly controlling the flow of gas therethrough and including an electric device for operating the valve;

e. said gas pipe assembly including a fitting extending through an opening in said platform and formed with a lateral orifice;

f. a burner secured to the upper end of said fitting and having a plurality of lateral ports;

g. a burner block mounted on said platform and having a longitudinal passage with an open end confronting said orifice and a closed end together with three angularly spaced openings communicating with said passageadjacent to its closed end;

h. an electric resistance igniter mounted on said platform in close proximity to one of said openings;

i. a normally open thermo-switch mounted on said platform and including a thermal element adjacent to the said opening adjacent said igniter;

j. an electric circuit including said thermo switch and said electric device;

k. a normally closed thermo-switch mounted on said platform and including a thermal element adjacent to another of said openings;

1. an electric circuit including said igniter and said normally closed thermo-switch;

m. a cover plate mounted on said platform below said burner and having an aperture positioned directly above the remainder of said openings, and

n. a main control switch included in the circuit of the igniter.

2. The automatic gas torch of claim 1 in which the electric device is a bi-metallic element.

3. The automatic gas torch of claim 1 in which the burner block has an inner end face spaced from said orifice, a top face and side faces with the open end of said passage being at said inner face and said openings being in said top and side faces.

4. The automatic gas torch of claim 3 in which said burner block is formed with a channel connecting said 8 openings.

5. The automatic gas torch of claim 1 in which said housing has a bottom formed with a central opening and a pair of lugs upstanding from said bottom in close proximity to said opening and said gas pipe assembly includes a lower pipe section formed with a tab received between said pair of lugs.

6. The automatic gas torch of claim 1 in which the platform has an annular depending peripheral flange fitting over the upper end of said housing and an upwardly extending annular flange of smaller diameter than said depending flange, together with a windscreen over said last mentioned flange.

Claims (6)

1. In an automatic gas torch, a. a vertical cylindrical housing; b. a horizontal platform mounted on the upper end of said housing; c. a gas pipe assembly extending through said housing; d. a valve in said assembly controlling the flow of gas therethrough and including an electric device for operating the valve; e. said gas pipe assembly including a fitting extending through an opening in said platform and formed with a lateral orifice; f. a burner secured to the upper end of said fitting and having a plurality of lateral ports; g. a burner block mounted on said platform and having a longitudinal passage with an open end confronting said orifice and a closed end together with three angularly spaced openings communicating with said passage adjacent to its closed end; h. an electric resistance igniter mounted on said platform in close proximity to one of said openings; i. a normally open thermo-switch mounted on said platform and including a thermal element adjacent to the said opening adjacent said igniter; j. an electric circuit including said thermo switch and said electric device; k. a normally closed thermo-switch mounted on said platform and including a thermal element adjacent to another of said openings; l. an electric circuit including said igniter and said normally closed thermo-switch; m. a cover plate mounted on said platform below said burner and having an aperture positioned directly above the remainder of said openings, and n. a main control switch included in the circuit of the igniter.

2. The automatic gas torch of claim 1 in which the electric device is a bi-metallic element.

3. The automatic gas torch of claim 1 in which the burner block has an inner end face spaced from said orifice, a top face and side faces with the open end of said passage being at said inner face and said openings being in said top and side faces.

4. The automatic gas torch of claim 3 in which said burner block is formed with a channel connecting said openings.

5. The automatic gas torch of claim 1 in which said housing has a bottom formed with a central opening and a pair of lugs upstanding from said bottom in close proximity to said opening and said gas pipe assembly includes a lower pipe section formed with a tab received between said pair of lugs.

6. The automatic gas torch of claim 1 in which the platform has an annular depending peripheral flange fitting over the upper end of said housing and an upwardly extending annular flange of smaller diameter than said depending flange, together with a windscreen over said last mentioned flange.

Images