Assembly for Steam Heating or Cooking Food Products and Its Method of Operation

The present invention relates generally to techniques for steam heating or cooking food products and more particularly to a specific assembly for and method of steam heating hot dogs and their associated buns to certain preset temperatures.

Those who are in the business of selling hot dogs for immediate consumption know that the hot dog meat tastes best when eaten at a particular temperature, specficially 150.degree. F. At the same time, the buns should be eaten at a different temperature, specifically, 170.degree. F. However, in actual practice, this is not always carried out. More often than not, the hot dog and its bun are heated together in a "steamer" and served at the same temperature which is controlled generally but not very accurately. More specifically, the steamer typically used is one which includes a chamber for containing a supply of hot dogs and buns and means for continuously supplying steam to the chamber from boiling water. The temperature in the steamer is controlled by controlling the temperature of the steam which, in turn, is regulated by controlling the temperature of the boiling water.

There are a number of disadvantages to using steamers of the type just recited. One primary disadvantage resides in the fact that the temperature of the steam determines the temperature of the steam chamber. Since the temperature of the steam is dependent upon the temperature of its source, that is, the boiling water, it is difficult to accurately maintain its temperature at a predetermined value. Moreover, should the temperature within the steam chamber drop substantially through heavy use, for example because a larger than usual number of cold hot dogs are initially placed therein, it is a relatively slow process to bring the chamber temperature back up to the desired operating level. This is because the temperature of the steam is no higher than the desired operating temperature of the chamber and therefore does not contain excess heat to provide rapid temperature changes. In order to add excess heat to the steam, the temperature of the boiling water would have to be raised to a temperature above the operating temperature of the chamber and this would itself be a slow process.

Another disadvantage to steamers of the type described also relates to the fact that the chamber temperature is operated at and is dependent on the temperature of the steam used to heat it. Because of this, both the hot dogs and buns are heated to the same temperature and this is generally the case even when separate chambers are provided.

Still another disadvantage of steamers of the type described relates particularly to those which utilize the same door for placing hot dogs and buns into and removing them from the steam chamber, which is often the case. Because of this, it is not always possible to ensure that the hot dogs and buns are removed from the chamber in the order in which they were placed therein. Thus, some hot dogs might stay in too long and become overheated and others may be taken out too soon and thereby never reach the desired temperature.

In view of the foregoing, it is one object of the present invention to provide an assembly for and method of steam heating or cooking given food products utilizing a steam chamber which can be accurately maintained at a particular predetermined temperature in a reliable and yet uncomplicated manner.

Another object of the present invention is to be able to bring the temperature of the steam chamber just recited back up to its preset level in a rapid fashion should the chamber temperature drop substantially for the reasons discussed previously.

Still another object of the present invention is to provide an uncomplicated, reliable and yet economical assembly for and method of steam heating or cooking given food products, especially hot dogs and buns, utilizing a number of different steam chambers simultaneously maintained at different temperatures, whereby different food products, for example, the hot dogs and buns mentioned, can be maintained at different temperatures.

Yet another object of the present invention is to provide a steam heating or cooking assembly which is designed to assure that the hot dogs and buns or like food products being steam heated or cooked are removed from their associated steam chamber in the order in which they were placed therein.

As will be described in more detail hereinafter, the particular steamer disclosed herein is one which includes an overall housing having at least one but preferably a number of internal cooking chambers and means for providing a supply of steam, for example, a suitable steam boiler. In accordance with one aspect of the present invention, each cooking chamber includes means such as a thermostat for sensing the temperature therein and the overall assembly includes means responsive to the temperature within each chamber for directing steam therein when and only when the temperature in that particular chamber is below a preset value, whereby to raise the chamber temperature to the preset value for heating or cooking the food products therein at that temperature. In accordance with another aspect of the present invention, the steamer includes a number of cooking chambers which are independently maintained at different temperatures utilizing the steam heating procedure just described. In this way, food products such as hot dogs and buns can be heated to different temperatures which, as stated previously, may be desirable.

Still another aspect of the present invention resides in the particular way in which each cooking chamber is designed. More specifically, as will be seen hereinafter, each chamber includes separate entry and exit doors and means within the chamber for guiding successive trays carrying given food products through the chamber from its entry door towards it exit door. This ensures that the food products are removed from the chamber in the order in which they were placed therein. In the case of hots dogs and buns, the trays used for carrying the buns are specifically designed to prevent puddles of water thereon (as a result of condensation) from coming into direct contact with the buns.

The overall steamer assembly and its method of operation will be described in more detail in conjunction with the drawings wherein:

FIG. 1 is a partially broken away front elevational view of the steamer designed in accordance with the present invention;

FIG. 2 is a side sectional view, in elevation, of a portion of the assembly illustrated in FIG. 1, taken generally along line 2--2 in FIG. 1;

FIG. 3 is a downwardly directed sectional view of the assembly illustrated in FIG. 1, taken generally along line 3--3 in FIG. 2;

FIG. 4 is an enlarged, partially broken away side elevational view of an entry or exit door forming part of the assembly of FIG. 1; and

FIG. 5 is a view similar to FIG. 4 but without the presence of the door.

Turning now to the drawings, wherein like components are designated by like reference numerals throughout the various figures, attention is first directed to FIG. 1 which shows an overall assembly 10 for steam heating or cooking given food products in accordance with the present invention. This assembly is especially suitable for simultaneously steam heating hot dogs to one preset but adjustable temperature and buns at a different preset but adjustable temperature. In an actual working embodiment, the hot dogs are heated to a precise temperature, for example 190.degree. F., and the buns are heated to a precise temperature, for example 208.degree. F. While these particular temperatures are not intended to limit the present invention, they have been selected based on the average temperature drop of the hot dog before it is consumed, that is, the average time it takes a customer to begin eating the hot dog from the time it leaves the steamer, so that he eats the meat at 150.degree. F. and the bun at 170.degree. F. Because overall assembly 10 is especially suitable for steam heating precooked hot dogs and buns, it will be described hereinafter for that purpose. However, it is to understood that the various inventive aspects of the assembly may be equally suitable for cooking other food products.

As illustrated best in FIGS. 1-3, overall assembly 10 includes a main housing 12 having what may be referred to as a vertically extending front side 14 and an opposite vertically extending back side 16 as well as a closed top surface 18, opposite sidewalls 20 and a bottom support base 22. An upper section of housing 12 contains six separate internal heating chambers 1-6 which extend from front side 14 to back side 16 adjacent to but isolated from one another by suitable partitions. Each of the chambers 1, 2 and 3 includes an entry door 24 on front side 16 and a vertically lower exit door 26 on back side 16. On the other hand, each of the chambers 4, 5 and 6 includes an entry door on back side 16 and vertically lower exit dooor on front side 14. In this way, hot dogs and buns can be simultaneously placed into and removed from the various chambers from opposite sides of the overall assembly, as will be seen hereinafter. Each entry or exit door is preferably rectangular in shape, and pivotally connected by suitable means such as hinges 28 at its bottom end to front side 14 or back side 16. In this way, each door opens downward to provide additional work surface when its associated chamber is opened. In a preferred embodiment, the hinges 28 or like means also serve to bias their respective entry and exit doors in closed positions. Each door includes its own handle 30 along a top edge thereof.

Referring specifically to FIG. 2, each of the chambers 4, 5 and 6 is shown including a ramp generally indicated at 32 extending downward through the chamber from a point adjacent its associated entry door 24 to a point adjacent its associated exit door 26. The ramp in chamber 6 is shown in plan view in FIG. 3. As seen there in conjunction with FIG. 5. the ramp is shown actually comprised of two right angle flanges 34 which are fixedly connected on opposite sides of the chamber along the bottom longitudinally extending edges thereof so as to provide a pair of upwardly facing ramped surfaces 36 extending downhill from entry door 34 towards exit door 26. While these flanges are satisfactory, in a preferred embodiment, they are not used. Rather, the bottom of the chamber is entirely flat and serves as the ramp surface. In either case, the ramps in the chambers 4 and 5 are preferably identical to the ramp in chamber 6 and therefore have identical ramped surfaces. While not shown, each of the chambers 1, 2, 3 includes an identical ramp comprised of its bottom surface or individual flanges having upwardly facing ramp surfaces. However, the ramps in chambers 1, 2 and 3 extend downward in the opposite directions. This is because the entry doors associated with chambers 1-3 are on the front side of the housing and the entry doors associated with chambers 4-6 are on the housing's back side, as discussed previously.

Having described each of the chambers 1-6, attention is now directed to the way in which hot dogs and buns are contained within these chambers. To this end, overall assembly 10 includes a number of trays which, as will be seen, are designed to support either a number of hots dogs or a package of buns for movement through a given chamber along an associated ramp from its entry door to its exit door. In a preferred embodiment, the trays for supporting hot dogs are designed slightly different than the trays used for supporting a package of buns. One hot dog tray is shown in chamber 5 (see FIG. 2) and another identical tray is shown in chamber 3 (see FIG. 3). Each of these trays which is generally indicated at 38 includes a flat support base 40 which is perforated to allow steam to pass therethrough. An upwardly extending rim 42 extends entirely around base 40 for preventing hot dogs (shown at 44 in FIG. 2) from inadvertently falling off the base. The combination base and rim are supported on four wheels 46 supported to the underside of the base by suitable support flanges 48. As best illustrated in FIG. 3, the tray is sized relative to its associated chamber such that two of the wheels ride on one ramp surface 36 while the other two wheels ride on the opposite ramp surface. In this way, the entire tray will automatically move by its own weight down the ramp from the entry door to and against the inside of the exit door. If the bottom surface of the chamber is used as the ramp, then two wheels 46 ride on one longitudinal edge section of the bottom surface while the other two wheels ride on an opposite longitudinal edge section.

While the trays used to support buns rather than hot dogs may be identical to trays 38, in a preferred embodiment of the present invention, they are slightly different. One such tray is shown in chamber 6 and generally designated by the reference number 50 (see FIGS. 3 and 5). This particular tray also includes a base 52 having three elongated through slots 54 which together define two spaced apart elongated base sections 56. As best illustrated in FIG. 5, each of these elongated sections projects upwardly relative to the rest of the base. In this way, a package of hot dog buns indicated by dotted lines at 58 is supported above and spaced from the rest of the base. Therefore, should any water accumulate on the base as a result of condensation within the steam chamber, the package of buns will be supported out of contact with the water. The remaining features of tray 50 may be identical to tray 38. More specifically, tray 50 may also include an upwardly extending rim 60 extending entirely around base 52 and four wheels 62 connected with and supporting the base for rolling movement down its associated ramp.

Referring specifically to FIG. 2, chamber 6 illustrated there is shown including a number of trays located in the chamber in a train-like end-to-end fashion. This resulted from putting the lowermost tray (the one closest to the exit door) into a chamber 6 through its entry door first and thereafter the next successive trays, each automatically moving down the ramp towards the exit door. It should be apparent from FIG. 2 that the first tray placed into the chamber is the first one to be taken out of the chamber, and so on, assuring that all of the trays are removed from the chamber in the order in which they were placed therein. In this regard, it is important that the hot dogs and buns (or other such food products) remain in their cooking chambers sufficiently long to heat up to the intended temperatures but not so long as to overcook otherwise the present process is independent of temperature.

Having now described the various trays and the way in which they move through corresponding steam chambers, attention is now directed to the way in which each chamber is independently steam heated for heating (or cooking) the hot dogs or buns therein. To this end, overall assembly 10 includes a steam boiler 66 which may be of any suitable, conventional type capable of providing a supply of steam from boiling water sufficient to heat all of the chambers in the manner to be described. The boiler may be operated electrically or by means of natural gas which is typically the case and is required to provide steam at a constant temperature at least as hot as the hottest chamber. In a preferred embodiment, boiler 66 provides a continuous supply of steam at about 275.degree. F. As will be seen below, suitable plumbing is provided for independently directing steam from boiler 66 to each of the chambers in a controlled fashion so as to maintain each chamber at a constant, preset but readily adjustable temperature, e.g. at 195.degree. F. in the case of a hot dog chamber and 208.degree. F. in the case of a bun chamber. For purposes of convenience, the boiler itself is contained within housing 12 directly under the chambers as best illustrated in FIG. 1, although this does not necessarily have to be the case. The boiler could be located at a remote location.

The plumbing and associated components for controlling the temperature in each cooking chamber includes suitable steam lines 68 extending from the boiler (actually a common manifold not shown) to the respective cooking chambers. Since there are six chambers illustrated, six steam lines are shown. In a preferred embodiment, each of the chambers includes its own elongated distribution plenum 70 which extends the length of the chamber and which is connected in fluid communication with an associated steam line for distributing incoming steam into the chamber along its entire length. While only chambers 4-6 are shown including these distribution plenums, it is to be understood that each includes at least one.

Returning to FIG. 1, all of the steam lines 68 are shown containing respective valves 72 which operate between open and closed positions. When each of these valves is in its closed position, its associated steam line is closed and therefore no steam reaches the associated chamber. On the other hand, when each valve is opened, its steam line automatically directs steam into the appropriate chamber. For reasons to become apparent below, these valves are preferably electrically actuated solenoid valves, although they could be of any other type which operate in the controlled fashion to be described.

In order to independently maintain the cooking chambers 1-6 at individual preset temperatures, each includes suitable means for sensing the temperature therein. A readily available thermostat having a temperature sensing element 74 and temperature adjusting component 76 will suffice. As illustrated in FIG. 1, the sensing element of each thermostat is fixedly mounted within a corresponding chamber and its associated temperature adjusting component may be mounted to a suitable control panel 78 forming part of housing 12. Means generally indicated at 80 may be provided in cooperation with each thermostat for visually indicating the actual temperature within its associated chamber. In any event, suitable and readily providable control means are provided for operatively connecting the thermostat associated with each chamber to the corresponding valve 72 so that the latter operates in the manner described immediately below.

So long as the temperature within any given chamber remains at the preset valve selected by the thermostat, its associated valve remains closed, thereby preventing any steam from entering the chamber. Should the chamber temperature go below its preset value, the valve is automatically opened and steam from boiler 66 automatically enters the chamber raising the temperature therein until it again reaches the preset level, at which time the valve is again closed. In other words, steam is directed into each chamber only so long as the temperature in that chamber is below the preset level. This is to be contrasted with the typical prior art steamer disclosed previously in which steam is continuously directed into its cooking chamber. The present approach more rapidly and reliably controls chamber temperatures and, unlike the prior art technique, can easily control different chambers at different temperatures and can rapidly make substantial changes in temperature within any given oven. This may be important for example if what is normally a bun chamber is needed for use as a hot dog chamber or vice versa. Utilizing the temperature values described previously, this requires a change of 13.degree. which can be made rapidly and in an uncomplicated way by the present technique, whereas it cannot be done in a rapid fashion utilizing the previously described approach since this latter approach requires that the entire supply of boiling water be either raised by 13.degree. or reduced by 13.degree. which is normally slow process.

Having described overall assembly 10 and the way in which it functions, the particular way in which hot dogs and buns are steam heated (or cooked) should be apparent. It should be equally apparent that the assembly itself could be utilized for steam heating and/or cooking other food products and that the assembly itself could include any number of chambers and different types of structural means serving as ramps 32. Moreover, while the entry and exit doors for each chamber have been shown on opposite sides of the assembly housing and while this is preferred, the two could be provided on the same side of the housing. In this latter case, the exit door would still be provided vertically lower than the entry door. However, rather than having a ramp which defines a straight line path, the ramp would be designed along a curved path, actually U-shaped in configuration as diagrammatically illustrated in phantom lines in FIG. 3. In other words, the ramp would extend downward from the entry door along a U-shaped path and back towards the lower exit door. In this way, an individual operator can oversee both ends of the given chamber at the same time. However, in order for the trays to make these U-shaped turns, their wheels will have to turn or ball bearings or the like could be used. It is also possible to provide the entrance door into each chamber from the top of the housing, although this might require a more complicated ramp or tray guidance configuration. Moreover, all of the entry doors could be provided on one side of the housing and the exit doors on the opposite side.