US3151610A

US3151610A - Broiler

Info

Publication number: US3151610A
Application number: US47188A
Authority: US
Inventors: Bernard B Hanson; Stoligrosz Eugene; James E Davis
Original assignee: Whirlpool Corp
Current assignee: Whirlpool Corp
Priority date: 1960-08-03
Filing date: 1960-08-03
Publication date: 1964-10-06
Anticipated expiration: 1981-10-06

Description

06f. 6, 1964 B. B. HANsoN ETAL BROILER 2 Sheets-Sheet l Filed Aug. 3, 1960 Ill 23 \22 31.510/2g\310,)/A A A/ y JQ' 25 16 m I Q E Inl fm1/anfora-F ernard/fansom ff emo/5 0 Oct. 6, 1964 B. E. HANsoN ETAL BROILER Filed Aug. 5, 1960 2 Sheets-snee?. 2

United States Patent O 3,151,616 BROILER Bernard B. Hanson, Eugene Stoligrosz, and llames E. Davis, all of Hamilton, (Ehio, assignors to Whirlpool Corporation, a corporation of Delaware Filed Aug. 3, 1966, Ser. No. 47,188 2 Claims. (Cl. 126-41) This invention relates to a broiler and particularly to an oven for cooking food that can also be used to broil food.

ln broiling with gas with an ordinary burner the llame length and heat intensity is sufcient to burn substantially all of the combustible gases or smoke evolved from the broiling food so that substantially no obnoxious smoke and gases pass from the broiler into the room. This condition, however, is not present with a broiler using the porous power burner which is now popular. 1n the porous power burner fuel gas and air mixture is forced under pressure through the burner which is usually in the form of a porous plate and is burned on one surface of the porous burner. Here the llame length is so short that the combustible gases given off from the food being broiled are not burned suiiciently completely so that smoke and irritating gases tend to pass from the broiler into the room.

One of the features of this invention is to provide a broiler using a porousl power burner and including means for promoting substantially complete combustion of the combustible gases given oft from the material being broiled.

Other features and advantages of the invention will be apparent from the illustrated embodiment thereof shown in the accompanying drawings. Of the drawings:

FIGURE l is a vertical sectional view through a household oven and broiler combination embodying the invention.

FIGURE 2 is a sectional view taken substantially along line 2 2 of FIGURE l.

FIGURE 3 is the electrical Wiring diagram for the illustrated embodiment.

The oven illustrated in the above drawings is generally similar to that disclosed in the copending Stoligrosz application Serial No. 836,229, filed August 26, 1959, now Patent No. 3,063,441, and assigned to the same assignee. This oven includes the baking space 1li formed in a charnber 11, a front access door 12 having an air veut 13 at the bottom thereof for incoming air, an air circulating fan 14- at the upper rear of the oven located at the top of a vertical due 15 having an entrance 16 to the fan at the top of the ilue and an exit 17 adjacent the bottom of the flue and the bottom of the oven. The fan 14 is operated by an electric motor 13 located rearwardly of the flue 15. There is also provided a porous plate burner at the top of the oven space 19 with means including a conduit 2i) for supplying a fuel gas and air mixture to the burner 19. This mixture is supplied by the conduit 2t) to a chamber 21 on the surface of the Vplate 19 opposite the burning surface 22. In this type of burner the air and gas mixture is forced through the plate 19 under pressure from an electrically operated blower 23 (FIGURE 3).

Porous burner plate 19 is located at the top of the oven. Immediately beneath the burner is adapted to be located a movable rack 24 for supporting meat 25 or the like during a broiling operation.

Also located in the top of the oven adjacent the surface 22 of the burner plate 19 is a llame detection switch 26 that includes a bimetal. There is also provided a spark plug 27 adapted to be used in conjunction with

spaced contacts

28 and 29 located adjacent the peripheral edge 313 of the plate 19 for igniting the gas emerging through the plate 19. The flame detection switch 26 is protected ice from accidental injury by means of a protective plate 31 located beneath the switch 26 and mounted on depending brackets 31a.

Extending around the peripheral edge 3l? of the porous burner plate 19 is a vent 32 that follows this edge and that extends generally upwardly. The vent is formed from sheet metal 33 and has an upwardly extending portion 34 at one side thereof. From this upwardly extending portion there is located an upwardly and outwardly sloped vent ilue 35 that empties into the ambient atmosphere through decorative louvers 36.

Positioned in the flue 35 is a plate valve 37 mounted for oscillation about a transverse axis 38. This valve is normally closed as shown in FIGURE l during the baking operation and is provided with a downwardly extending operating arm 39.

In order to open the valve 37 when desired there is provided a bimetal strip 4i) that curls toward the arm 39 when heated and away from the arm 39 when cool. This bimetal strip 46 is anchored at one end to an electrical insulating fitting 41 and is provided at its upper movable end with a contact pad 42 for contacting the operating arm 39 of the valve 37. Wrapped around the bimetal 4i) for heating the same is an electric resistance heater wire 43.

The wiring diagram shown in FIGURE 3 in addition to the oven air blower 14, gas and air supply blower 23, fan detection switch 26 and

ignition spark contacts

28 and 29 previously described also includes a timer motor 44, timer contacts 45 and 46, an oven selector switch 47 including

movable contacts

48, 49, 50 and 51 and ixed

contacts

52 and 53, oven thermostat 54, air pressure switch 55, time delay switch 56, time delay switch heater 57, safety resistor 58, gas valve solenoid 59, transformer 66 for the ignition spari;

contacts

28 and 29 and relay coil 61 and relay contacts 62.

The electric power to the electrical circuit is supplied by

leads

63 and 64. Between these leads is connected the timer motor 44 by line 65. Contacts 45 and 46 are in line 66 which extends from lead 63 to the switch 47. This line 66 is connected to

contacts

52 and 53.

Extending from power lead 64 is line 67 with the fuel gas and air blower 23 being connected between this line 67 and contact 48 by means of line 68. The heater 43 for the bimetal 46 is connected by means of line 69 between line 67 and movable contact 49. The blower 18 for the oven air is connected by means of line 76 between movable contact 50 and line 67. A line 71 which extends between movable contact 51 and line 67 contains in series the thermostat 54, air pressure switch 55, time delay switch heater 57, relay coil 61 and flame detection switch 26. The time delay switch 56 is in line 72 extending between line 71 and a line 73 which contains the safety resistor 58 and the gas valve solenoid 59 and which is connected to line 67. Between the resistor 58Y and solenoid 59 is connected one end of a line 74 whose other end is connected to one of the fixed contacts 75 of the relay contacts 62. The other xed contact 76 is connected by way of a line 77 to one side of the transformer 60 whose other side is connected by means of a line 78 to the line 67.

During operation of the oven for baking the timer contacts 45 and 46 are closed and the

contacts

48 and 52 are closed and the

contacts

5G and 53 and 51 and 53 are closed. This serves to energize the blower 23 which supplies air land gas mixture to the burner plate 19 and the oven air blower motor 18 which circulates air through the oven by way of the ue 15 and the

openings

17 and 16.

When broiling of meat or the like is to be done the timer contacts 45 and 46 are closed and contacts 48, 49

and 52 are closed. Similarly,

contacts

51 and 53 are Y closed. This closing of the contacts serves to activate 'f The quick shut-oi or safety Y a'safety feature. Y

' is shut off power to the ignition circuit willvbe interrupted.

the fuel gas and air mixture blower 23 and the heater 43 for thebimetal 40. The heater 43 causesthe bimetal 40 to bend toward the operating arm 39 of the valve 37 with the result that the contact pad 42 engages the arm 39 and turns the valve 37 to the open position indicated by the broken lines in FIGURE 1. This open the vent 32 to the ambient atmosphere through the decorative louvers 36 so that smoke and other combustible` gases from the meat Y25 being broiled tend to ow toward and through the vent 32. As` the vent 32 is closely adjacent the peripheral edge of the burner 19 these combustible gases are subjected to heat from the burner plate 19. In order to intensify the heat there is provided means adjacent the entrance 79 to the vent 32 for concentrating the combustible gases adjacent the burner 19 prior to the gases entering this entrance. In the embodiment shown this means includes a flange 80 located at the outer extremity of the entrance 79 and extendingtoward the burner plate 19. As a result of this construction the combustible gases from the food being broiled are subjected to relatively high temperature so that they are ignited and burned. The resulting gases then ow upwardly in the vent 32 -and out the flue 35 and are substantially clear of smoke. Y

As can be seen, therefore, the electrical system for the illustrated embodiment provides for closing of the valve 37 'during baking so that the oven operates in a normal manner. However, during broiling the valve 37 is opened Vso that the smoke and other combustible gases from the by closing the-

contacts

50 and 53. The air pressure setV lup by this blower 18 closes the air pressure switch 55 bodiment shown in the accompanying drawings, it is ourV intention that the invention be not limited by any of the details of description, unless otherwise specified, butl rather be construed broadly within its spirit and scope as set out in the accompanying claims.

The embodiments of the invention in which an exe elusive property or privilege Vis claimed are defined as follows:

1. A broiler, comprising: means forming archamber; a porous power burnertherein having a substantially continuous porous surface exposed to said chamber; means for supplyingra lfuel gas and air mixture under pressure to said burner for ilow therethrough and Combustionon said surface; means adjacent said surface for supporting which results in voltage being applied across the ignition Y circuitry. One branch of the current set up by this voltage passes'through the safety switch heater 58, the relay coil 61 and the ame detection switch 26 which is normally closed when cold. Another branch of the current set up by this voltage passes through the switch 56 and to the relay contacts 62. A lead 74 from the relay contact 75 bypasses the resistor 58 and energizes the-gas valve solenoid 59. A lead 77 from the other relay contact 76 energizes the primary of the step-up-transformer 60. The voltage induced in the secondary winding of this transformer is large enough to force a spark across the gap between the

ignition spark contacts

28 and 29;

Vthus causing burner ignition.

AfterV normal ignition the-llame detection switch 26 which isY adjacent the burner 19V opens because of heat received from this burner. The opening of this switch Y deenergizes the relay coil 61 and the Vsafety switch heater V57'. Thisopens the

relays contacts

75 and 76 inV relay the ignition sparking. f

resistor 58 is supplied as If'electrical power `to the apparatus This will immediately shut off the entire` system. The

supplied the main burner` valve solenoid could not operate. If it werepermitted to Yreopen 4raw 'gas' would ow in large quantities-into the oven and could not be food for broiling; means forming a vent from said chamber having an open entrance portion that is located in its entirety extending around said porous burner and adjacent said surface or the burning of combustible gases from said broiling food substantially completely at said entrance portion from heat supplied fromsaid combustion on said surface, said ventY varying in vertical height and having a highest portion; Van upwardly and outwardly sloped vent Vflue substantiallyat said highest portion; a normallyclosed valve in said ue; and means for opening said valve during said broiling.

2. A broiler, comprising:v means forming a chamber; a porous power burner therein having a substantially continuous porous surface exposed to said chamber; means for supplying a fuel gas and air Ymixture under pressure to said burner for flow therethrough and combustion on said surface; means adjacent said surface for supporting food for broiling; means forming a vent from said chamber having an open entrance portion that is located in its entirety extending around said porous burner and adjacent said surface for Athe burning of'combustible gases from said broiling food substantially,V completely at said entrance portion from heat suppliedfrom said combustion on said surface, said vent varying in vertical height 1 Vand having a highest portion; an upwardly and outwardly sloped vent ue substantially at said highest portion; a normally closed valve insaid ue; heat actuated means for opening said valve during'said broiling; an electric heater in thermal conducting relationship with said heat 1 actuated means; and means for electrically energizing said heater to open said yvalve during said broiling.

References Cited in the tile of Ythis patent i UNTED STATESVPATENTS 1,223,308 Bone et al. Apr. 17, 1917 1,515,234 Woodson Nov. .11, 19241 1,932,170 -gBibb Oct. 24,1933Y 2,102,482V Parker- Dec. 14, 1937 2,164,078 'Y Parker 'Iune 27, 1939 2,164,079 Parker June 27, 1939 2,219,787 Parker Oct. 29, 1940 2,323,821 Lindemannfet al. July 6, 1943 2,862,095 Scofield Nov. 25,Y 1958 `2,908,267 Hess f v f Ocala, 1959

Claims

1. A BROILER, COMPRISING: MEANS FORMING A CHAMBER; A POROUS POWER BURNER THEREIN HAVING A SUBSTANTIALLY CONTINUOUS POROUS SURFACE EXPOSED TO SAID CHAMBER; MEANS FOR SUPPLYING A FUEL GAS AND AIR MIXTURE UNDER PRESSURE TO SAID BURNER FOR FLOW THERETHROUGH AND COMBUSTION ON SAID SURFACE; MEANS ADJACENT SAID SURFACE FOR SUPPORTING FOOD FOR BROILING; MEANS FORMING A VENT FROM SAID CHAMBER HAVING AN OPEN ENTRANCE PORTION THAT IS LOCATED IN ITS ENTIRETY EXTENDING AROUND SAID POROUS BURNER AND ADJACENT SAID SURFACE FOR THE BURNING OF COMBUSTIBLE GASES FROM SAID BROILING FOOD SUBSTANTIALLY COMPLETELY AT SAID ENTRANCE PORTION FROM HEAT SUPPLIED FROM SAID COMBUSTION ON SAID SURFACE, SAID VENT VARYING IN VERTICAL HEIGHT AND HAVING A HIGHEST PORTION; AN UPWARDLY AND OUTWARDLY SLOPED VENT FLUE SUBSTANTIALLY AT SAID HIGHEST PORTION; A NORMALLY CLOSED VALVE IN SAID FLUE; AND MEANS FOR OPENING SAID VALVE DURING SAID BROILING.