A stainless steel sheet metal housing has three sets of supports which are vertically disposed, with respect to each other. One or more burners are mounted on the lower most support. A heat distribution member or members are mounted on the intermediate support. Grids or griddles are mounted on the upper most support. All of the burners, heat distribution members, grids and griddles may be lifted in or out of said housing whereby different combination of components may be provided. The heat distribution means may be either a plurality of ceramic briquettes or a radiant metal plate. This way, the charbroiler may be configured in many different ways to accommodate the changing tastes of customers, either in the short term over the course of a day or in the long term over a number of weeks, months or years.

BACKGROUND OF THE INVENTION 
This invention relates to restaurant class cooking equipment and more 
particularly to charbroilers which are especially--but not 
exclusively--well adapted for smaller restaurants. 
The restaurants which may use this invention are, roughly speaking, 
represented by fast food restaurants, small cafes, diners and the like. In 
general, these types of restaurants feature either grid or griddle 
cooking. In a grid type of cooking, there are a number of spaced rods 
which directly support a food product (steak, patty, wiener, etc.) while 
it is cooking. The heat causes grease to drip out of the food, fall on a 
hot surface, burn and issue up smoke which affects the taste of the food. 
The spaced rods leave burn marks on the food to provide a cosmetic effect. 
The griddle type of cooking is a flat sheet of metal which is more like a 
frying pan that fries a product without either the smoke taste or the 
cosmetic effect of the burn marks. 
When the restaurant is large or is part of a fast food chain, for example, 
management decides upon a type of cooking which it wishes to use and buys 
the proper and dedicated cooking equipment to implement that decision. 
However, if the restaurant is a relatively small "mom and pop" type of 
business, it is not always advantageous to buy dedicated equipment. The 
customer's taste may change during the day, for example, they may want 
griddle fried eggs in the morning and charbroiled patties and steak at 
night. Or, the customers taste may change over time as they shift between 
griddle fried and charbroiled foods as, for example, when news events 
report the latest theories on cholesterol or the causes of stomach cancer. 
Another consideration relates to avoiding hot and cold spots by spreading 
heat more evenly, which give a more predictable quality control over the 
food product. One approach to heat spreading is to interpose a ceramic 
material between a flame and a cooking surface. A commonly used ceramic is 
a layer of small pillow shaped briquettes about the size and shape of 
charcoal briquettes. The other approach (radiant cooking) is to provide a 
sheet of metal positioned between the flame and the food product in order 
to spread the heat more evenly. Different restauranteurs have different 
opinions on these two systems, preferring one over the other. Therefore, a 
desirable design would give the restauranteur an option of ordering either 
a ceramic or radiant style of charbroiling equipment, and then 
retrofitting it t become the other style in order to accommodate changing 
tastes. 
Yet another consideration is the different and changing demands which may 
be placed upon a restaurant by customer's fickleness. One night, perhaps 
the ratio of orders for griddle and grid cooking may be opposite the ratio 
on the next night. This problem might be more severe for restaurants along 
a busy highway which is frequented at different times by people from many 
different parts of the country. 
Regardless of how cooking equipment is designed, it must still meet the 
requirements of appropriate regulatory agencies, one of which is the 
American Gas Association (AGA). Therefore, options are limited. It becomes 
quite difficult to provide a single charbroiler with a high level of 
flexibility which meets all of the conflicting needs, rules, and 
regulations. 
Accordingly, in view of all of these and other considerations, an object of 
the invention is to provide a charbroiler which offers a maximum degree of 
flexibility, with the least cost and labor requirements for switching over 
from one style of cooking to another. Here, an object is to enable a 
change over from grid to griddle and back again with almost no work. In 
this connection an object is enable a maximum freedom in selecting almost 
any of many different configurations of cooking surfaces in order to cater 
to almost an orders that customers may present. 
Another object of the invention is to enable an in-the-field retrofit of a 
charbroiler in order to switch it between ceramic and radiant 
configurations. 
SUMMARY OF THE INVENTION 
In keeping with an aspect of the invention, these and other objects are 
accomplished by providing a surface support system which enables grids and 
griddles to be interchanged at will and in different ratios. In one 
embodiment, the geometry of the parts is that two grids and one griddle 
occupy exactly the same space on the support system. In other embodiments, 
there may be other proportions; however, there should be an even multiple 
of widths so that the entire cooking surface may be covered by either 
grids or grills or combinations thereof. The space between the burners and 
the surface unit is arranged to enable a quick change over between parts 
used for ceramic and radiant cooking.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The inventive charbroiler 20 (FIG. 1) includes a stainless steel cabinet 
having a pair of doors, 22, 24, providing access for any suitable purposes 
such as storage, servicing equipment, or the like. The cabinet is coupled 
at 26 to a gas main, the flow of gas to burners being controlled by valves 
at 28, 30. A grease tray 32 is positioned near the griddle 34 in order to 
catch drippings therefrom. This tray 32 is slightly more than 3-inches 
wide in order to accept the end of a standard spatula for cleaning 
purposes. 
The top of the charbroiler 20 includes front and back spaced parallel rails 
38, 40 (FIGS. 1, 2, 3), for supporting griddle 34 or grids 36. Since the 
grids and griddles merely sit upon the rails 38, 40, they may be 
installed, removed, or interchanged merely by lifting them on or off. In 
one case, the geometry is such that two grids exactly fits the space 
occupied by one griddle. However, any suitable ratio of sizes may be used 
provided that the widths are a whole multiple so that the grids and 
griddles may be interchanged to exactly fit the space at the top of the 
charbroiler. In the example of FIG. 1, a radiant plate 42 rests upon 
intermediate level spaced parallel front and back rails 62, 64 at a level 
which is well below that of the grid 36 and griddle plate 34 in order to 
distribute the heat more uniformly. 
The grid 36 or griddle 34, or any suitable combination thereof, are simply 
placed on the front and back rails 38, 40. Therefore, in the morning, the 
entire upper cooking surface area of the charbroiler may be covered by 
griddle plates 34. Perhaps at 10-11 AM, some people may begin to 
requesting charbroiled hamburgers while other customers are still ordering 
fried eggs. Therefore, maybe half of the griddle plates may be replaced by 
grids. Perhaps at the noon rush everyone wants charbroiled hamburgers, in 
which case, the entire surface area may be covered by grids. 
The cross section of the oven is seen in FIG. 2 as including a storage 
compartment 44 which is accessed via the doors 22, 24 of FIG. 1. Within 
the housing and above the storage compartment is a suitable insulation 46, 
48, for containing the heat within the upper part of the cabinet where the 
burners are located and where the cooking occurs. 
In FIGS. 2, 3, burners 50, 52 are supported in the front by gas fitting 
nipples 56 (FIG. 2) and are supported in the back by members which hook 
into supports 54 at the back of the cabinet. The nipples are parts of a 
pipe system for conveying gas from a manifold 58 to the burners 50. No 
orifice (nipple) change is required. 
Intermediate level spaced parallel front and back rails 62, 64 support 
either a ceramic briquette grate 66 (FIG. 3) or a radiant plate 42, which 
may be interchanged by lifting them in or out of the cabinet. The ceramic 
material is a standard commercial item which is purchased, for example, 
from Ferro, Sebring, Ohio (Briquette #638). These are small pillow shaped 
pieces of ceramic which have the general configuration of a charcoal 
briquette. Their function is to provide thermal inertia, to spread the 
heat uniformly under the cooking surface, and to become hot enough to burn 
grease dripping on them in order to give a smoky taste. 
A spatter shield (not shown here) may be provided for the cook to use as he 
sees fit. The spatter shield rests on the cabinet sides and back rail 38. 
However, it may also be used in connection with grids, if desired. 
FIG. 4 is a side elevation and FIG. 5 is a top plan view of a radiant plate 
42. This plate 42 may be used interchangeably with grate 66 and ceramic 
70; the two would not be used simultaneously. In general, the radiant 
plate 42 is in the size and shape of two grates 66. The top surface of the 
radiant plate 68 is approximately a louver formed by a series of plates 
74, each bent at an angle of approximately 45.degree. . Each in the series 
of plates 74 is spot welded at the points indicated by asterisks (as at 
76, for example) in FIG. 5. In addition, a somewhat box-like stiffening 
part 78 is provided o each plate 74 to contain drippings that are 
incinerated, turned to ash, by the burner heat in order to produce smoke. 
This louver arrangement directs streams of warm air toward the product on 
the grid or griddles, with a substantially uniform distribution of heat in 
a desired pattern over the entire cooking surface. The upper surface of 
the radiant plate 42 becomes hot enough to burn grease dripping on it, 
thereby giving a smoky taste to food resting on a grid 36. 
More particularly, the louvers may open either toward the front or the back 
of the griddle depending upon how the user elects to install them. The 
cooking surface will tend to be hotter on the side toward which the 
louvers direct the hot air, as compared to the temperature on the side 
away from the directed air. The chef using the charbroiler will have his 
own preferences for how the heat is distributed across the cooking surface 
and therefore will install the radiant plate 42 in order to aim the stream 
of hot air, as he chooses. 
In general, it is through that most people will aim the hot air toward the 
back of the cooking surface. This way the chef will reach over and 
otherwise be personally exposed to the cooler cooking area. Usually, he 
will lay out hamburger patties, for example, on the hotter back of the 
cooking surface to sear the meat for locking in the juices. Then, he will 
flip the hamburger forward to the cooler cooking surface for a complete 
cooking. The hotter and cooler cooking surface areas also aid the chef in 
filling a customer's request for a rare or well done product. 
FIGS. 6-8 show the griddle assembly 34 which may be used in either of two 
modes in place of or on top of the grids 66. The cooking surface is a 
sheet of metal 80 which may be in the order of a quarter of an inch thick 
for example, to provide thermal inertia. Welded under the plate 80 is a 
heat baffle in the form of a sheet of metal, which defines an open heat 
accumulation space 84 under cooking surfaces 80. The rear part of the open 
space 84 terminates in a chimney 86 (FIG. 7) which provides entrance and 
exit as the hot air expands and contracts while it heats and cools. 
Side plates 88, 90 (FIG. 8) depend from the edges of the griddle assembly. 
These side plates enable the griddle to fit over two grids 36, 36 so that 
the griddle may be installed without removing the grids. If the grids are 
removed, front and back notches 92, 94 of the griddle fit over the front 
and back rails 38, 40. Either way, the side plates 88, 90 collect a 
blanket of hot air beneath the baffle plate 82. 
The advantages of the invention are (1) a flexible system which can switch 
almost instantly between smoky and non-smoky taste, grid cooking and 
griddle cooking, and (2) an easy retrofitting of cooking between ceramic 
and radiant cooking. Thus, the charbroiler is designed for the relatively 
small and independent restaurant which needs a single piece of equipment 
with great flexibility. 
Those who are skilled in the art will readily perceive how to modify the 
invention. Therefore, the appended claims are to be construed to cover all 
equivalent structures which fall within the true scope and spirit of the 
invention.