US3490854A

US3490854A - Burner and control assembly

Info

Publication number: US3490854A
Application number: US656100A
Authority: US
Inventors: Dennis A Pipes
Original assignee: Essex International Inc
Current assignee: Raytheon Technologies Corp
Priority date: 1967-07-26
Filing date: 1967-07-26
Publication date: 1970-01-20
Anticipated expiration: 1987-01-20

Description

Jan. 20, 1970 Filed July 26, 1967 D. A. PIPES BURNER AND CONTROL ASSEMBLY 2 Sheets-Sheet l 1 NVEN TOR. DEN/v15 A. P/PEs WWW I 24:1}

fink KM M ATTOPNE Y5.

Jan. 20, 1970 PIPES 3,490,854

BURNER AND CONTROL ASSEMBLY Filed July 26, 1967 2 Sheets-Sheet 2 INVENTOR. DENNIS A. D1055 BYW, l Mia. 141 M ATTOENEYE.

United States Patent O 3,490,854 BURNER AND CONTROL ASSEMBLY Dennis A. Pipes, Mansfield, Ohio, assignor, by mesne assignments, to Essex International, Inc., Fort Wayne,

Ind., a corporation of Michigan Filed July 26, 1967, Ser, No. 656,100 Int. Cl. F23n 5/00 US. Cl. 431-82 15 Claims ABSTRACT OF THE DISCLOSURE The disclosure relates to a burner and control assembly which may be used as a normally burning pilot burner assembly and thermal actuator with a 100% fuel shut-off. A body supports a burner with a first flame port and gaseous fuel to this flame port is controlled by pilot valve means, either a single valve or two separate valves. A temperature-responsive actuator controls the valve means and also a manual actuator controls the valve means so that the valve means, may be manually actuated to light the pilot flame whereupon the thermal actuator is heated and opens the valve means so that the manual actuator may be returned to off condition and the pilot flame will be maintained lit. Upon extinguishment of the flame the thermal actuator cools to close the valve means for a 100% fuel shut-01f.

BACKGROUND OF THE INVENTION In gas burners such as used in household appliances, ranges, water heaters and the like, it is a common requirement that these devices be safe in operation. One requirement is that if the main burner be somehow accidentally extinguished, then the flow of gas to such main burner should be cut off. Usually a standing pilot is employed in conjunction with such main burner and current safety regulations permit gas to escape from such pilot burner, even if accidentally extinguished, because this is a small amount of gas, so long as the appliance is adequately vented. However, other gas appliances which may or may not be adequately vented have more strict safety regulations whereby 100% gas shut-off is required in the event that the main burner and pilot burner are extinguished. This means that the small amount of gas escaping from the pilot burner must also be shut off. This is termed a 100% gas shut-off type of control. Such systems which in the past have achieved 100% gas shut-off have in general been fairly complicated requiring additional control systems, not only the one for the main burner but an additional control for the pilot burner, and the additional cost and complexity have mitigated against the general commercial use of such 100% gas shut-off pilot burners.

In the prior art there were attempts made to have a normally operating pilot burner with a thermal actuator for this pilot burner, however such devices frequently required two separate gas supplies and two separate flame ports, one supply for each flame port. Also a separate valve was established for each of the two flame ports and often the manual actuators were placed in an inconvenient position adjacent the flames to make it extremely hazardous to attempt to light the pilot flame manually. Also in some prior attempts there was a single pilot burner and thermal actuated valve rather than a separate pilot burner directing a flame on the thermal actuator.

Accordingly an object of the invention is to provide a burner assembly which obviates the above-mentioned disadvantages. Another object of the invention is to provide a burner and control assembly which is simple and compact as well as rugged.

"ice

bly wherein valve means is actuated both by a temperature responsive actuator and a manual actuator.

SUMMARY OF THE INVENTION The invention may be incorporated in a burner and control assembly comprising, in combination, a valve body having a gas inlet, valve means mounted relative to said body and being connected to said gas inlet, temperature responsive actuator means connected to operate said valve means, a manual actuator connected to operate said valve means, and a first flame port connected in communication with said gas inlet through said valve means and directing heat of a flame therefrom to said temperature responsive actuator means, said temperature responsive actuator means including first and second leg means each having first and second ends, means mounting said first end of said first leg means relative to said body, means interconnecting said second ends of said leg means, means connecting said first end of said second leg means to actuate said valve means, and said first and second leg means having diflerent thermal coeificients of expansion, whereby said manual actuator may be actuated from a first to a second condition to cause gas to be emitted from said first flame port which may be ignited to heat said temperature responsive actuator means to maintain said valve means open whereupon said manual actuator may be returned to said first condition and whereby upon flame failure said temperature responsive actuator closes said valve means for a complete gas shutoff.

Other objects and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is a longitudinal sectional view to an enlarged scale of a burner and control assembly incorporating the invention;

FIGURE 2 is an end view of the gas inlet end of the assembly of FIGURE 1;

FIGURE 3 is a longitudinal sectional view of a modification of the invention; and

FIGURE 4 is an end view of the gas inlet end of the assembly of FIGURE 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIGURES l and 2 of the drawing illustrate the preferred embodiment of the invention, however it will become apparent hereinafter that many modifications may be made to the invention within the scope of the hereinafter appended claims.

FIGURES l and 2 show a burner and control assembly 11 which includes generally a valve body 12, pilot valve means 13, a tubular pilot burner 14, a temperature-responsive actuator means 15, and a manual actuator 16. The valve body 12 may be made of any suitable metal, for example steel, and includes a threaded gas inlet 19 to a recess 20. The threaded gas inlet 19 may be connected to a gas supply conduit, not shown. The tubular pilot burner 14 has first and

second ends

21 and 22, respectively. The first end 21 of the pilot burner 14 may be fixedly carried in an aperture in the valve body 12 and sealed thereto as by welding or silver solder. The first end of the tubular pilot burner 14 is in gas communication with the recess 20, as controlled by the valve means 13. An intermediate portion of the pilot burner 14 contains a first flame port 23 from which a control flame 24 may issue. The second end 22 of the pilot burner 14 is remote from the body 12 and has a terminal flame port 25 from which a terminal flame 26 may issue and which will be primarily responsible for acting as a pilot flame for a main burner, not shown.

The valve means 13 includes a circular valve seat 28 on the first end 21 of the pilot burner tube 14. A valve gasket 29 cooperates with the valve seat 28 in order to make sealing connection with such valve seat to control gas flow to the

ports

23 and 25. The valve gasket 29 is carried on a cantilever leaf spring 30 which has a mounting end 31 fixed as by welding inside the recess 20 of the valve body 12.

The temperature-responsive actuator means 15 includes first and

second legs

33 and 34 respectively. The first leg 33 is a tubular member having a first end fixedly carried in an aperture 35 of the valve body 12. The second leg 34 is an inner rod inside said tubular first leg 33-. The second ends of both the first and

second legs

33 and 34 are threaded and interengaged at 36. A screwdriver slot 37 may be provided for adjustment of the temperature-responsive actuator means. A sealing material 38 may seal the end of the tubular first leg 33 to prevent escape of gas. The first end 39 of the second leg 34 acts on the valve means 13. This first end 39 has a reduced neck 40 disposed in an aperture 41 in the cantilever leaf spring 30. A shoulder 42 contiguous with the reduced neck 40 engages the cantilever leaf spring 30 to permit actuation thereof upon relative expansion and contraction of the first and second leg means 33 and 34. The shoulder 42 acts close to the mounting end 31 of the cantilver spring 30 in order to provide a motion amplifying movement to the valve gasket 29. The first and

second legs

33 and 34 are made from materials of different thermal coefficients of expansion. Preferably the inner rod 34 is made from a high expansion stainless steel and the outer tube 33 is made from a low expansion stainless steel such as Invar.

The manual actuator 16 includes a push-button 45 mounted on a rod 46 which is slidably journalled in an aperture 51 in the valve body 12. A cam 47 on the inner end of the rod 46 is disposed to coact with a cam follower 48 on the distal end of the cantilever leaf spring 30. A conical shoulder 50- is fixed on the rod 46 for sealing engagement with the inner end of the aperture 51 in order to normally seal therewith under the urging of a spring 52 surrounding the rod 46 in order to prevent escape of gas through this aperture 51. When the push-button 45 is depressed against the urging of the spring 52, the cam 47 coacts with the cam follower 48 to open the valve means 13, namely to move the valve gasket 29 away from the valve seat 28. This permits gas to move from the recess 20 to the

flame ports

23 and 25.

OPERATION The preferred embodiment of FIGURES 1 and 2 permits a normally operating pilot flame to control valve means supplying gaseous fuel to the flame and also a manual actuator will also control the same valve means. When it is desired to light the pilot flames 24 and 26, the manual actuator 16 may be depressed to open the valve means 13 whereupon gas will issue from the

flame ports

23 and 25. This gas may be ignited in any one of several convenient ways, for example, a match, ignition coil, spark gap or the like, to establish the pilot flames 24 and 26. The terminal flame 26 is primarily to establish a pilot flame for a main burner associated therewith, but not shown in the drawings, and the control flame 24 is primarily to provide heat for the temperatureresponsive actuator means 15. This temperature-responsive actuator 15 includes the first and

second legs

33 and 34 which have a differential rate of expansion with ap- 4 plied heat. The heat from the flame 24 makes the inner rod 34 expand more than the outer tube 33, and hence this actuates the valve means 13 by bending the cantilever leaf spring 30 and moving the valve gasket 29 away from the valve seat 28. Accordingly this establishes the valve means 13 in an open position to maintain the pilot flames 24 and 26. Thereafter the manual actuater 16 may be released to return to its first condition as urged by the spring 52. Upon flame failure for any reason, the temperatureresponsive actuator 15 will cool to close the valve means 13 and this will shut off the gaseous fiow and hence there will be 100% shut-01f of the gas flow from this burner and control assembly 11. Accordingly this burner assembly 11 may be used in connection with those gas appliances wherein 100% fuel shut-off not only from the main burner but also from the pilot burner 11 is required.

MODIFICATION OF FIGURES 3 AND 4 FIGURES 3 and 4 show a modified burner and control assembly 61 including a valve body 62, valve means 63, a tubular pilot burner 64, temperature-responsive actuator means 65, and a manual actuator 66. Many parts are similar to those parts found in the preferred embodiment of FIGURES 1 and 2 and have the same reference numerals. For example, the tubular pilot burner 64 has the control and

flame ports

23 and 25 and the temperature-responsive actuator means 65 includes the first and second legs means 33 and 34. The valve means 63 includes a pilot valve 69 which is a valve gasket 70 carried on a cantilever leaf spring 71 with this leaf spring 71 actuated by the temperature-responsive actuator 65 as in the preferred embodiment. The gasket 70 cooperates with a valve seat 72 on the first end of the tubular burner 64. The valve means 63 also includes a second valve or manual valve 74 which comprises a valve seat 75 in the valve body 62 and a conical valve member 76 carried on the inner end of a rod 77. The rod 77 has threads 78 received in a threaded aperture in the valve body 62 and also has a manual handle 79 for manipulation. The manual valve 74 is disposed in a by-pass passageway 80 interconnecting the recess 81 in the valve body 62 and the first end 21 of the tubular pilot burner 64. An aperture 82 in the first end 21 of the tubular burner is a part of this by-pass passageway 80. A sealing gasket 83 prevents escape of gas past the threads 78.

OPERATION The cold or room temperature condition of the modified burner and control assembly 61 of FIGURES 3 and 4 is as illustrated in the FIGURES 3 and 4, with both valves 69 and 74 closed. This is a first condition of the manual valve 74. To place the burner and control assembly 61 in operation, the manual valve 74 would be moved from the first condition to a second or opened condition, by turning the manual handle 79. This permits gas from the gas inlet 19 to pass through this by-pass passageway -80 and manual valve into the tubular pilot burner 64. It will issue from the

flame ports

23 and 25 and may be ignited in any desired manner, for example, a match, ignition coil or spark gap to establish the flames 24 and 26. Again the terminal flame 26 will be primarily that established to ignite a main burner, not shown. The first or control flame 24 will impinge upon the temperatureresponsive actuator 65 to heat same and cause the inner rod 34 to expand relative to the tube 33 and hence open the pilot valve 69. At this point the manual valve 74 may be closed and the burner assembly 61 will be in full operation. Upon any outage of the flames 24 and 26, the temperature-responsive actuator 65 will cool to close the pilot valve 69 and hence this will establish a gas shut off from the burner and control assembly 61.

It will be noted that both burner assemblies 11 and 61 are established from only a single gas supply, and only a single flame port 24 is used for control of the temperature-

responsive actuator

15 or 65. This single flame port 23 establishes the flame 24 which controls the valve means 13 or 63. Also it will be noted in both modifications that the pilot burner 14 or 64 is separate from the thermal probe or temperature-

responsive actuator

15 or 65 which in turn controls the valve means supplying gaseous fuel to this tubular pilot burner 14 or 64. The burner assembly 11 or 61 may be made quite small and compact and since only metal parts are used without any electrical circuit, the device is quite rugged to withstand rough handling in shipping and in usage. Also the device is self-contained with the pilot burner establishing a flame directed upon the

thermal probe

15 or 65 to establish the proper alignment of the parts at the time of manufacture, and this alignment will not change because of careless mounting of the device in relation to the main burner.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. A burner assembly comprising, in combination,

a valve body having a gas inlet,

valve means mounted relative to said body and being connected to said gas inlet,

temperature responsive actuator means connected to operate said valve means,

a manual actuator connected to operate said valve means,

a pilot burner tube having a first end connected to said valve body,

an intermediate portion of said burner tube having a first flame port connected in communication with said gas inlet through said valve means and directing heat of a flame therefrom to said temperature responsive actuator means,

said temperature responsive actuator means including first and second leg means each having first and second ends,

means mounting said first end of said first leg means relative to said body,

means interconnecting said second ends of said leg means,

means connecting said first end of said second leg means to actuate said valve means,

said first and second leg means having different thermal coeflicients of expansion,

a cantilever spring,

a valve member mounted on a movable portion of said cantilever spring,

a valve seat fixed to said first end of said pilot burner tube for cooperation with said valve member as part of said valve means,

and a shoulder on said first end of said second leg means bearing against said cantilever spring to actuate said valve means,

whereby said manual actuator may be actuated from a first to a secondcondition to cause gas to be emitted from said first flame port which may be ignited to heat said temperature responsive actuator means to maintain said valve means open whereupon said manual actuator may be returned to said first condition and whereby upon flame failure said temperature responsive actuator means closes said valve means for a complete gas shut-off. 2. A burner assembly as set forth in claim 1 wherein a single gas supply is used with said burner assembly.

3. A burner assembly as set forth in claim 1 including a plurality of flame port means and said valve means supplies said first flame port for heating said temperature responsive actuator means.

4. A burner assembly as set forth in claim 1 wherein said burner assembly is a pilot burner and said flame port establishes a pilot flame for use in conjunction with a main burner.

5. A burner assembly as set forth in claim 1, including a tubular pilot burner carrying said flame port, said tubular pilot burner being separate and distinct from said temperature responsive actuator means.

6. A burner assembly as set forth in claim 1, including a reduced neck on said first end of said second leg means, an aperture in said cantilever spring to receive said reduced neck, said shoulder on said second leg means being contiguous with said reduced neck and bearing against said cantilever spring, and said first and second leg means being relatively expansible and contractible with temperature changes to have said shoulder actuate said valve means.

7. A burner assembly as set forth in claim 1 including a tubular pilot burner separate from said temperature responsive actuator means, said first flame port being on said tubular pilot burner and directing a flame on said temperature responsive actuator means, and said temperature responsive actuator means controlling said valve means to control gas flow to said first flame port.

8. A burner assembly as set forth in claim 1, including spring means to return said manual actuator from said second to said first condition.

9. A burner assembly as set forth in claim 1 wherein said valve means is a single valve, said temperature responsive actuator means and said manual actuator being connected to actuate said single valve.

10. A burner assembly as set forth in claim 9 including a push button and spring return manual actuator carried in said valve body and having a cam connected to actuate a cam follower carried on said valve means for actuation thereof.

11. A burner assembly as set forth in claim 10 including a cam follower on a distal end of said cantilever leaf spring, said first leg means being a tube and said second leg means being a rod contained therein with the first end of said rod connected to actuate said cantilever leaf spring.

12. A burner assembly as set forth in claim 1 including a manual valve separate from a pilot valve, said pilot valve and said manual valve being included in said valve means, said temperature responsive actuator means connected to operate said pilOt valve, and said manual actuator connected to actuate said manual valve.

13. A burner assembly as set forth in claim 12, including a tubular pilot burner having said first flame port thereon, a by-pass passageway between said valve body and the proximal end of said tubuar pilot burner, and said manual valve being connected in said by-pass passageway to control the flow of gas therethrough.

14. A burner assembly as set forth in claim 13 wherein said manual valve and manual actuator are screw actuated.

15. A burner assembly as set forth in claim 14 wherein said by-pass valve and passageway control gas flow to said first flame port and said pilot valve controls gas flow to said first flame port, said first flame port establishing a flame impinging on said temperature responsive actuator means.

References Cited UNITED STATES PATENTS 714,023 11/1902 Palmer 43 177 942,158 12/ 1909 Yockey, et al. 43177 944,771 12/ 1909 Campbell 43177 1,058,046 4/ 1913 Garber 431-77 2,274,786 3/ 1942 Green 43156 580,574 4/1897 Fowler 251303 X 2,185,364 1/1940 Andrews 236--102 FOREIGN PATENTS 61,199 10/ 1954 France. 150,070 2/ 1953 Australia.

EDWARD G. FAVORS, Primary Examiner