CA1104017A - Barbecue oven - Google Patents

Abstract

BARBECUE OVEN

Abstract of the Disclosure A barbecue oven comprising a barbecue compart-ment having a door hingedly mounted in a door opening in a front wall of the compartment and spaced from a top and bottom wall thereof. A heating unit is provided in the barbecue compartment and having an elongate heat-radiating surface disposed the side walls and positioned between a top edge of the door opening and the top wall to radiate heat downwardly towards a spit turret in the compartment.
The spit turret is drivingly secured in the compartment between the side walls and disposed in the path of radia-tion of the radiating surface. Drive means is provided to rotate the turret. A liquid collecting tray is provided in at least a portion of the bottom wall below the spit turret to collect hot liquids dripping from food-stuff supported by the spit turret.

Description

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BACKGROUND OF INVENTIO~ ~ ~
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~a) Field of the Invention The present invention relates to a barbecue oven and more particularly to improvements in the con~
struction of such ovens wherein there is provided a heat-; ing unit disposed between a top edge of a door opening and ~` a top wall of the unit to radiate heat do:wnwardly toward a centerline of a turret and in interference with a spit turret whereby foodstuff on the turret will be cooked and : 10 the dr.ippings thereof will be collected at the bottom of :~
the oven, completely away from the heating unit.
(b) Description of Prior Art :~ Various types of cooking or heating ovens have heretofore been provided as exemplified by U.S~ Patent No, 3,074,360, 2,927,479 or 2,855,842. These are only -~
examples of prior art ovens of the type described herein.
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These exemplify some of the problems solved by the present : : ~ invention. There has long existed the need to provide a barbecue oven that can cook foodstuff quickly and equally and which is constructecl for easy use and cleaning and which is not hazardous.
SUMM~RY OF INVENTION
: It is an object of the present invention to provide an improved barbecue oven which provides quick ;
and equally finished cooking, which is safe and easy to operate, and easy to clean.
Another object of the present invention is to provide a barbecue oven having a heating unit which zom-bines infrared and convecti.on heating and arranged whereby the heating unit is isolated from hot liquid drippings of .

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foodstuff being cooked.
Another object of the present invention is to provide a turret arrangement wherein the drive mechanism is sealed from the interior of the oven to prevent ingress of liquids from foodstu~f into the drive mechanism.
Another ohject of the present invention is to provide a barbecue oven which is easy to operate and clean and which is compact in construction and further providing the stacking of two or more of the ovens.
~ 10 According to the above features, from a broad :~ aspect, the present invention provldes a barbecue oven :
comprising a barbecue compartment defined by spaced apart side walls, a back wall, top and bottom walls and a front wall, a door hingedly mounted in a door opening in said front wall and spaced from said top and bottom walls, a heating unit in said barbecue compartment having an elongate heat radiating surface disposed intermedlate said side walls and positioned between a top edge of said door opening and said top wall to radiate heat downwardly towards a spit turret, said spit turret being drivingly secured in said compartment between said side walls and disposed in the path of radiation of said radiating surface, drive means to rotate said turret, a liquid collectlng tray in at least a portion of said bottom wall below said spit turret to collect hot liquids dripping from foodstuff supported by said spit turret, said spit turret having a rotatable drive shaft having a skewer support disc secured adjacent one end thereof, a disc-shaped drive drum secured adjacent the other end thereof, said drive drum having a plurality of skewer engaging sockets therein disposed 30 in a circumferential axis of a front face thereof with their long axis parallel to said drive shaft, each said socket being `, ~

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r secured to a planetary gear rotatably driven by a drive gear secured to said rotatable dxive shaft to cause rotation of said sockets, said drive drum housing said drive and plane tary gears therein, each said socket being secured in a ~ ~:
~` pressure seal bearing arrangement.
::~ BRIEF DESCRIPTION OF DRAWINGS
A preferred embodiment of the present invention ; will now be described with reference to the examples ~here-~ ~ of illustrated by the accompanying drawings in which:

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FIGURE 1 is a front view of the barbecue oven :
having a further oven stacked thereon which is partly ~- fragmented, FIGU~E 2 is a side view of Figure 1 also having ` S the upper s-tacked oven partly fragmented, FIGURE 3 i5 a :Eragmented section view of the :
spit turret construction' .
FIGURE 4 is a fragmented partly sectioned view of the construction of the pressure seal bearing member, . ~:
FIGURE 5 is an enlarged fragmented end view of the pressure applying hinge, FIGURE 6 is a fragmented front view of the pres-sure hinge of Figuxe 5, FIGURE 7 is an electrical switching diagram of 15 the electrical circuit of the oven, FIGURF. 8a is a fragmented side view of the self- :
. ~ aligning bearing, and FIGURE 8b is an end view of Figure 8a.
DESCRIPTION ~F PREFERRED EMBODIMENTS
Referring now to the drawings, and more par-ticu- ;~
larly to Figures 1 and 2I there is shown generally at 10 the barbecue oven of the present invention~ As shown in these figures, a further bar~ecue oven 10' is stacked on ~; : top of the barbecue oven 10 and additional ovens may be stacked if required. The oven 10 defines a barbecue com-partment 11 which is defined by vertical spaced-apart side walls 12, a back wall 13, a top and bottom wall 14 and 15, ; respectively, and a front wall 16. A door 17 is hingedly ,~
moun-ted in a door opening 18 in the front wall, which ; 30 opening is spaced from the top and bottom walls.

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As illustra-ted in Figure 2, a heating unit 19 is : ~
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provided in the barbecue compartment 11 and has an elongate ~ .
heat-radiating surface 20 (not fully illustrated) which ;
` extends substantially be-tween the side walls 12 and which is ; 5 positioned between a top edge of the door opening 18 and the top wall 14 whereby to radiate heat downwardly towards : .;
the centerline of the turret shaft 24 as illustrated by the heat radiating flow lines 21.
A spit turret 22 is drivingly secured in the com-partment 11 between the side walls 12 and is disposed in the path of radiationt indicated by the flow lines 21, whereby foodstu~f supported on skewers (not shown~ and ~ :
supported by the turret 22 will. be rotated and.moved in ~ .
interference with the path of radi.ation. Suitable dri.ve means 23 ls provided to impart rotational drive to a drive .:
shaft 24 which operates the spit turret 22.
~ ~ liquid coLlecting tray 25 is formed a~ove the bottom wall 15 to collect hot Liquid drippings from the . foodstuff being suppo.rted by the turret and cooked within :~ 20 the oven. The inside ~alls of the oven are preferably ~ lined with a stainless steel sheet 26 for ease of cleaning ; an~ sanita~y purposes. The drippings within the tray 25 can be collected automaticaLly during cooking by providing an output pipe 27 which may be connected to conduits or ; 25 which may have a valve therein permitting periodic drainage of liquids within the tray 25.
P~eferring again to Figure 2, the heating unit 19 is an infrared heater having the heat-radiating surface ::
20 thereof constructed as a gas conductive porous ceramic rectangular surface or electrically heated elements. It ' 1 .~ .

can be seen that the plane of the heat radiati.ny surface . 20 is angulated to face the spit turret 22~ urther, the ; heating unit 19 is secured on a mounting bracket 28 which incorporates a heat deflector wall 29 which extends in . 5 spaced-apart relationship to the top wall 14 and sub-: stantially across the compaxtment 11 between the side `~ walls 12 a short distance towards the back wall 13. As can be seen, the top wall 14, back wall 13 and side walls 12 are thick insulated walls. The reason for this is that the majorlty of the heat i.s concentrated towards these walls~
The purpose of the heat deflector wall 29 is to transmit convection heat in the compartment 11 from the heating surface 20 and in the direction of the spit turre-t to increase the temperature in the compartment 11 and -to ~ :
create heat flow in combination with the vent opening 30 provided in a top portion of the back wall 13, This vent opening 30 is provided to suitable piplng (not shown) and ~ the air carrying fumes is evacuated outwardly of a room :. 20 The heat deflector wall 29 may also be provided wi-th a plurality of fins tnot shown) on the outer heating surface thereo~. This would provide a larger surface ar~a to be heated to generate more convection heat within the oven.
: However, the deflector wall construction as shown in Fi.gure 2 has been found satisfactory for the dimension of the oven hereinshown~
Re~erring now additionally to Figures 5 and 6, there is shown the construction of a pressure applying hinge 40 which secures the door 17 to the front wall 16.
Such a hinge 40 is provided in a respec-tive lower side edge Q~7 : ':
of the front door and is constructed such as to provide closing pressure against the door when positioned towards its closed position as shown in Figure 2.
As shown in Figures 5 and 6, the hinge 40 com-prises a hinge flange 41 which is conveniently secured tothe front wall 16 at right angles thereto, thus extending outwardly from the front wall 16. A hinge pin 42 is secured in each lower marginal side edge of the door 17 and secured for axial rotation in a respective hinge bore 42' provided in the flange 41 and located a predetermined distance fro~
the front wall 16 of the unit and substantially in alignment with .the front wall 17' of the door 17 and forwardly of the central plane 43 of the door. A spring-loaded ball 44 is located in a ball cavi~ty 45 provided in each marginal side edge 46 of the door. A helical coil spring 47 is located .
within the ball cavity 45 between an end wall 48 and the ball ; ~4 to exert outward pressure on the ball 44~ Thus, the ~all is constantly biased under outward pressure and retained within the cavity 45 by the inner surface 49 of the flange 41.
A ball recelving bore 50 is pro~ided in the hinge flange 41 and offset from the central longitudinal axis of the hinge pin 42 and positio~ed to receive a portion of the spring~loaded ball therein to cause the ball to exert for-ward biasing pressure on the door 17 towards the door open-ing 1~. Of course, the bore 50 is of smaller diameter than the diameter of the ball 44 whereby the ball will only partly enter within the cavity S0. The cavity 50 is located bet-ween the front wall 16 of the oven and the hinge pin and - 30 above the hinge pin~ A further ball receiving cavity 51 ~ - 7 - :

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` is positioned below the hinge pin at a convenient location --~
to retain the door in a downward open position 52 as !~ illustrated in phantom lines in Figure ~. It can be seen ~ -~
that with this type of pressure-applying hinge arrangement, ~;
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the door is completely sealed about the door opening 18 and very little force is required to open the door from its closed position. Further, this eliminates the need of cantilever weights which usually results in large door structures providing interference to prevent stac]cing ovens one on top of the other. ~`
Referring now to Figure 3, there is shown the construction o~ the spit turret 22. As previously described, :~ , .;
; the spit turret is secured on a rotatable drive shaft 24.
The spit turret comprises a skewer suppor-t clisc 53 which `
is located adjacent one end of the drive shaft 24 and con-veniently secured thereto. This disc is provided with a ` -. .
plurality of bores 54 to removably secure skewers (not shown) ~;l ; thereinto. Other skewer supporting means may also be pro-vided instead of bores 54~
A disc-shaped drive drum 55 is secured adjacent the other end of the drive shaft 24 at the end near a drive compartment 56 of the oven 10. q'he drive drum 55 conslsts of a disc-shaped front wall 57 having a plurality of skewer .

enga~ing sockets 58 secured thereinto and transverse to 1 25 the plane of the disc 57 and equidi~tantly spaced along a circumferential axis thereof, whereby the long axis of the sockets 58 extends parallel to the drive shaft 24. Each -~
of the sockets SS is secured to a respective planetary gear 59 which is rotatably driven by a drive gear 60 which is 30formed on a self-aligning bearing 61. As the drive shaft 24 is rotating, the drive gear 60 will impart rotation to ' the planetary gears 59 and cause the sockets 58 to rotate whereby skewers engaged in the socket cavities 58' ~see :~
Figure 4) w.ill rotate on their long axis. SimultaneoUSly the circular disc front wall 57 of the drive drum S5 will rota-te as it is secured by suitable means, such as lock -bolt 62, to the drive shaft 24 Referring to Fi.gures 8a and 8b there is shown `
the construction of the self-aligning bearing 61 having the drive gear 60 integrally formed therewith~ The sel.f-aligning bearing ~1' at the other end of the shaft has the same construckion features except it is not formed -~
with a gear, but me.rely supports the end to the shaft 2~.
Both bearings 61 and 61' are connected to a respective one of the opposed side walls 12 in an identical : 15 manner and therefore only one connection will be described.
:: ~ circular bore 20 is provided in the wall 12 to support the bearing 60 which is of circular cross-section. As seen ~:
clearly in ~igure 8b, the bore 120 is of yreater diameter than the diameter of the bearing 61. Thus, a clearance 121 is provided between the bearing 24 and a portion of the circumference of -the bore 120.
A wall deflection groove 122 is formed adjacent the end of the bearing 61 and extends transverse to the axis of rotation of the drive shaft 24~ The grove 122 is ; 25 in a portion only of the circumference of the bearing and defines a flat bottom wall 123. A locking Jcey 124 con-~: stitute~ by a flat metal bar is secured by bolts 125 to the wall 24 with a lower portion of the bar extending through the groove 122 and spaced above the bottom wall 123.
. 30 The groo-ve 122 is wider and deeper than the ~' ~, ~ _ 9 _ thickness and length of the key 124 which ex-tends into the groove, whereby to permit de~lection of the side walls about the bearing, when the walls are heated, in order to prèvent stress forces on the bearing w~lich in turn wo~ld cause wearing of the bearing and shaft.
: In order to prevent ingress of liqui~ drippings from the foodstuff within the socket 58 and the friction bearing sleeves 71 and the gears 59 and 60 within the drum housing 63 ~defined by a top wall 64 and rear wall 65 together with front wall 57~, each of the sockets 58 are ~.
secured b~ a pressure seal bearing arrangement~ Referring ; now to ~'igure 4, there is shown the construction o~ the pressure seal bearing arrangement and it comprises one or more frlction bearing sleeves 71 (concentrically positioned about the outer cylindrical wall 70 of the skewer engaging socket 58 whereby to receive the socket 58 in rotation fit with the ~riction bearing 71 and wi-thin the drum chamber 63)~ .
The planetary gear 59 is secured to the inner end 72 of ~: ~ the soc~et 58. An 0-ring front seal arrangement, herein .
: 20 constituted by;one or more 0-ring seals ~shown two 73 and 7~
is provided about a forward portion of the socket 58 and are compressed hetween an 0-ring washer 75 and the front face 76 . of the friction bearing sleeves 71 and cylindrical wall 70~ .
:~ The 0-ring washer 75 is retained in position by a retaining ~.
ring 77 secured in a circumferential groove 78 in the forward end of the socket 58. The O-rings 73 and 74 are :~
: squeezed between the O~ring washer 75 and the ront face 76 of the bearing sleeve 71 and cylindrical wall 70 by pressure applying means which is constituted by a helical spring 79 which is retaine~ about the cylindrical wall 70.
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The helical spring 79 is compressed be-tween the inner sur~ace 80 of the disc-shaped front wall 57 and an inner pusher ring 81 which is positioned about the socket 58 in a rear portion thereof and extending between the rear faces 82 of the friction bearing sleeves 71 and :~
the cylindrical wall 70 and the inner face 83 of its ~;
associated planetary gear 59. ~One or more rear O-ring seals 84 or other axial bearing are positioned about the socke~ 58 between the inner pusher ring 81 and the inner face 83 of the planetary gear 59. It can be seen that the helical spring 79 thus applies outwaxd pressure In the ~ direction of arrow 85 against the pusher ring 81. This : : pressure is transmitted to the O-ring seaLs 84 or other axial bearing and to the planetary gear 59 which i5 secured to the socket 58. Accordingly the soclcet 58 is constantly under inward pressure in the direction of arrow 85 within .
the drlve drum 55. This pressure is transmitted to the O- .
; ring seals 7:3 an:d 74 via the O-ring washer 75 Thus both . ..
the front~and rear O-rings are under pressuxe preventing seepage of fluids within the drum. A pxotective disc flange (cover) 86 provides close seaLing about the front poxtion of the socket.
Preferably the dxlve fox the spit turret 22 is , 1 provided by an electric motor ~Figure 7) designated by ~umeral 90 and lS conveniently housed within the drive compartment 56. The electric motor has an output drive ~ ..
~- ~ (not shown) which engages a drive gear 9L (see Figures 1 and 3) to transmit rotational drive to the drive shaft 24 through a cran~ arm 92 whlch is secured to the free end of the drive shaft 24 and is provided with a cran~c coupler 93 which couples the drive gear 91 to a crank arm 92. In case .'`; : .

of power failure the crank coupler 93 is relocated to the end of the crank arm 92 in position 93'. This dis- :
engages the drive gear gl and the system may be operated manually whereby the gas burner does not need electrici-ty to operate the turret~ .
Referring to Figure 7, there is shown the electrical switching arrangement with the drive mo-tor 90O ~;
A main switch 100 is conveniently located on a control panel 101 ~see Fi~ure 1~ on the oven front wall 16 along : 10 with the timex switch 102, which automaticaLly operates the cooking cycle and causes gas or electricity for the `
heating unit 19 to shut off when the cycle is complete.
The door switches 104 and 105 are secured within the door ~.
- 17 and cut off the power to the motor 90 and the timer switch 102, when the door 17 is in an open position. A
foot switch 106 is provided in parallel with the door .
switch 104 to connect the power to the motor 30 in case :.
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the door 17 is open if it is desired to load or unload the skewers (not shown) from the turret. By depressing the foot switch 106 momentarily the turret is rotated in increments to position the skewers alternately to the position 94 adjacent the door 17 (s~e Figure 2). The indicator Light 107 is mounted on the control panel 101 to indicate that the heating uni-t 19 is deenergized by the timer 102 at the end of the cooking cycle. Whenever the . motor 90 is switched off, the heating unit 19 is also switched off. If the heating unit 19 was left operable, the foodstuff closest to that heater would be overcooked and may burn due to excess heat. The thermostat switch 108 maintains the preset temperature by switching on and off the gas or electricity to the heating unit 19.
'' - 12 _ It is within the ambit of the present invention to provide any obvious rnodificatlons of the example of the preferred embodiment described herein, provided such modi- :
flcations fall within the scope of the claims appended here-to.

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Claims (13)

The embodiments of the invention in which an exclu-sive property or privilege is claimed are defined as follows:-

1. A barbecue oven comprising a barbecue compartment defined by spaced apart side walls, a back wall, top and bottom walls and a front wall; a door hingedly mounted in a door opening in said front wall and spaced from said top and bottom walls, a heating unit in said barbecue compartment having an elongate heat radiating surface disposed inter-mediate said side walls and positioned between a top edge of said door opening and said top wall to radiate heat downwardly towards a spit turret, said spit turret being drivingly secured in said compartment between said side walls and dis-posed in the path of radiation of said radiating surface, drive means to rotate said turret, a liquid collecting tray in at least a portion of said bottom wall below said spit turret to collect hot liquids dripping from foodstuff sup-ported by said spit turret, said spit turret having a rotat-able drive shaft having a skewer support disc secured adjacent one end thereof, a disc-shaped drive drum secured adjacent the other end thereof, said drive drum having a plurality of skewer engaging sockets therein disposed in a circumferential axis of a front face thereof with their long axis parallel to said drive shaft; each said socket being secured to a planetary gear rotatably driven by a drive gear secured to said rotatable drive shaft to cause rotation of said sockets, said drive drum housing said drive and planetary gears therein; each said socket being secured in a pressure seal bearing arrangement.

2. A barbecue oven as claimed in claim 1, wherein a heat deflector wall is provided in said compartment spaced from said top wall intermediate said heating unit and back wall to transmit convection heat in said compartment from said heating unit in the direction of said spit turret to increase the temperature in said compartment.

3. A barbecue oven as claimed in claim 2, wherein said heat radiating surface is a gas conductive porous ceramic rectangular surface, the plane of said heat radiating surface being angulated to face said spit turret.

4. A barbecue oven as claimed in claim 3, wherein said heat deflector wall is provided with a plurality of fins on an outer heating surface thereof, said convection wall being spaced from said top wall of said barbecue compartment.

5. A barbecue oven as claimed in claim 2, wherein said door is provided with a pressure applying hinge in a res-pective lower side edge thereof, said hinge applying closing pressure against said door when positioned in a closed posi-tion against said door opening.

6. A barbecue oven as claimed in claim 5, wherein said hinge comprises a hinge flange secured to said front wall at right angles thereto, a hinge pin in each lower marginal side edge of said door secured for axial rotation in a respective hinge bore of said flange a predetermined distance from said front wall forwardly of the central plane of said door, a spring loaded ball in each said marginal side edge biased outwardly from a surface of said side edge, a ball receiving bore in said hinge flange offset from the central longitudinal axis of said hinge pin and positioned to receive a portion of said spring loaded ball therein to cause said ball to exert forward biasing pressure on said door to-ward said door opening.

7. A barbecue oven as claimed in claim 6, wherein said ball receiving cavity is positioned above said hinge pin bore between said hinge pin and said front wall, and a further ball receiving cavity below said hinge pin to retain said door in a downward open position when said door is dis-placed on its hinge pins clear of said door opening.

8. A barbecue oven as claimed in claim 1, wherein said pressure seal bearing arrangement comprises a housing secured in a front wall of said drive drum, one or more friction bearing sleeves about said socket and received in rotational fit within said housing, said planetary gear being secured to an inner end of said socket, one or more O-ring front seals about said socket forwardly of said friction bearing sleeve and housing, an O-ring washer secured about a forward portion of said socket in front of one or more said O-ring seals, and pressure applying means urging said O-ring flange against said one or more O-ring seals to provide a pressure seal between said socket and said housing to prevent ingress of liquids within said friction bearing sleeves and disc drive drum.

9. A barbecue oven as claimed in claim 8, wherein said pressure applying means is a helical spring about said housing and compressed between an inner surface of said front wall of said drive drum and an inner pusher ring positioned about said socket in a rear portion thereof, a one or more O-ring seal about said rear portion between said inner pusher ring and said planetary gear, said helical spring applying pressure against said planetary gear through said rear seal and inner pusher ring to bias said socket inwardly and main-tain said front and rear seal under sealing pressure.

10. A barbecue oven as claimed in claim 1 wherein said drive means comprises a drive gear freely rotatable about a drive shaft of said spit turret, a crank arm secured to said drive shaft, a coupler connecting said crank arm to said drive gear to permit said drive shaft to be rotated by said drive gear through said coupler and crank arm when said drive gear is rotated.

11. A barbecue oven as claimed in claim 10 wherein said coupler is securable to an end portion of said crank arm to impart manual rotational displacement to said drive shaft and disconnecting said drive gear from engagement with said drive shaft.

12. A barbecue oven as claimed in claim 1 wherein said drive means includes an electric motor to rotate said spit turret, a timer switch to automatically operate a cooking cycle by energizing said motor for a predetermined cycle, a door switch to reenergize said motor when said door is open and to shut-off said heating unit, and a further switch in parallel with said door switch to energize said motor when said door is open whereby to permit removal of skewers removably secured to said turret.

13. A barbecue oven as claimed in claim 1 wherein said drive gear is in toothed engagement with said planetary year and secured to a self-aligning bearing extending through a circular bore in one of said side walls, said bore and a bearing connecting portion extending through said wall being of circular cross-section with said bore being of greater diameter, a wall deflection groove in a portion of the circumference of said bearing connecting portion, a locking key secured to said wall and extending into said wall def-lection groove, said deflection groove being wider and deeper than the thickness and length of said key portion disposed within said groove to permit said wall to deflect.