# Patent

## Title
Matchbox oven

## Abstract

A matchbox oven is disclosed. The matchbox oven includes a housing having a cavity and first and second openings. A surface is movable only in a single axis and a single plane, a first portion of the surface is located substantially within the cavity when a second portion of the surface is located substantially outside the cavity, and the first portion of the surface is located substantially outside the cavity when the second portion of the surface is located substantially within the cavity. A plurality of stoppers are attached onto the surface, wherein two of the stoppers substantially block the first and second openings when one of the first and second portions of the surface is located within the cavity.

## Background
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of co-pending U.S. patent application Ser. No. 13/077,143, filed Mar. 31, 2011, and entitled “Matchbox Oven,” which is hereby incorporated by reference.


FIELD OF INVENTION
The present invention relates to ovens in general, and in particular to a matchbox oven capable of providing continuous food cooking while minimizing heat loss, thereby minimizing energy consumption.
BACKGROUND OF THE INVENTION
A conveyor oven typically has a first opening through which uncooked food enters and a second opening at the opposite end of the oven through which cooked food exits. A stainless steel conveyor belt is commonly used to carry food items through a heated cavity between the first and second openings. The conveyor belt extends past both openings sufficiently to allow safe insertion and retrieval of food items. This arrangement allows food items to be placed on the conveyor belt on a continuous basis to achieve sequential steady-state cooking. The only limit to how many substantially identical food items may be placed in the conveyor oven is the speed of the conveyor belt, which correlates to the residence time inside the heated cavity for food items to be sufficiently cooked.
When food items offered by a commercial foodservice operation such as a restaurant are to be cooked at the same temperature for the same amount of time, a conveyor oven is particularly advantageous. The operator need only set the temperature and conveyor belt speed as necessary to cook the selected foods. Once these two parameters are set, the oven may be operated continuously without any further adjustments.
Even a person unskilled in the art of cooking is able to prepare high-quality cooked food products simply by placing them on the conveyor belt of a conveyor oven. The ease of operation and high throughput make conveyor ovens highly desirable in restaurants and other commercial foodservice settings.
However, conveyor ovens also have their disadvantages. For example, most commercial foodservice operations offer a variety of food items, such as pizza, chicken, vegetables and pie, which require a wide range of cooking times and heat transfer profiles. Even a single food order at a restaurant may include a variety of food items, and different food items require different cooking times. Conveyor ovens are very efficient when cooking similar food items, but not for cooking a variety of food items that require vastly different cooking times and heat transfer profiles. In addition, the two openings contribute to tremendous heat loss during the operation of conveyor ovens. The lost heat must be replaced in order to maintain cook temperature, and as a result conveyer ovens are not energy efficient.
Consequently, it would be desirable to provide an improved oven with the efficiency of conveyor ovens while enabling different cooking times, all without a large amount of heat loss associated with conveyor ovens.
SUMMARY OF THE INVENTION
In accordance with a preferred embodiment of the present invention, an oven includes a housing, a slider, a mover and a heat source. The housing includes a cavity and a first and second openings. The slider includes a first and second platforms configured for receiving food items, and a first, second and third stoppers that serve as oven covers to prevent heat within the cavity from escaping through the first and second openings. The slider can be moved in and out of the cavity through the first and second openings by the mover such that one of the platforms is generally inside the cavity and other platform is generally outside the cavity where it can receive a food item. The heat source provides heat to the cavity to heat up any food item placed on a portion of the slider located within the cavity.
In accordance with another embodiment of the present invention, an oven includes a housing having a cavity. The housing includes a first opening and a second opening, the first opening and the second opening defining a cavity length. A rigid surface is provided for receiving items, the surface having a length greater than the cavity length, and a plurality of stoppers attached on the surface. The surface is configured to be moved to a position in the cavity such that a first stopper covers the first opening and a second stopper covers the second opening to prevent heat within the cavity from escaping through the first opening and the second opening. A mover is operatively connected to the surface to linearly move the surface bidirectionally only in a single axis and a single plane, to cause items placed on the surface to be moved in and out of the cavity through at least one of the first opening and the second opening.
In accordance with another embodiment of the present invention, an oven includes a housing having a cavity and first and second openings. A surface is movable only in a single axis and a single plane, a first portion of the surface is located substantially within the cavity when a second portion of the surface is located substantially outside the cavity, and the first portion of the surface is located substantially outside the cavity when the second portion of the surface is located substantially within the cavity. A plurality of stoppers are attached onto the surface, wherein two of the stoppers substantially block the first and second openings when one of the first and second portions of the surface is located within the cavity.
In accordance with another embodiment of the present invention, a method for heating an item in an oven is provided. The oven includes a housing having a cavity with a first opening and a second opening, and a surface including a first item loading section and a second item loading section. The method comprises the steps of moving the surface only in a single axis and a single plane for positioning the first item loading section in the cavity through the first opening and the second food loading section outside the cavity through the second opening; blocking the first opening with a first stopper attached to the surface; blocking the second opening with a middle stopper attached to the surface; moving the surface only in the single axis and the single plane for positioning the first item loading section outside the cavity through the first opening and the second item loading section in the cavity through the second opening; blocking the first opening with the middle stopper attached to the surface; and blocking the second opening with a second stopper attached to the surface.
All features and advantages of the present invention will become apparent in the following detailed written description.



BRIEF DESCRIPTION OF THE DRAWINGS
The invention itself, as well as a preferred mode of use, further objects, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 is a front view of a matchbox oven, in accordance with a preferred embodiment of the present invention;
FIG. 2 is a cross-sectional view of a cavity within the matchbox oven from FIG. 1, in accordance with a preferred embodiment of the present invention;
FIG. 3 is a diagram of a heating and airflow system within the matchbox oven from FIG. 1, in accordance with a preferred embodiment of the present invention;
FIGS. 4a-4c are a top view and side views of the slider within the matchbox oven from FIG. 1, in accordance with a preferred embodiment of the present invention;
FIGS. 5a-5c illustrate a method of cooking when only one of food loading sections of the matchbox oven from FIG. 1 is being used, in accordance with a preferred embodiment of the present invention; and
FIGS. 6a-6f illustrate a method of cooking when both food loading sections of the matchbox oven from FIG. 1 are being used, in accordance with a preferred embodiment of the present invention.



DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Referring now to the drawings and in particular to FIG. 1, there is depicted a front view of a matchbox oven, in accordance with a preferred embodiment of the present invention. As shown, a matchbox oven 10 is defined by a housing 11 having a cavity 12. Housing 11, as well as cavity 12, has a first opening 18 and a second opening 19. Matchbox oven 10 includes a heating and airflow system (not shown) to supply heat to cavity 12 for heating up any food items that have been carried into cavity 12 from either first opening 18 or second opening 19 via a slider 20.
Matchbox oven 10 also includes a first control panel 15 and a second control panel 16. First and second control panels 15, 16 are preferably implemented with touch screens but they can also be implemented with keypads and liquid crystal displays (LCDs). An operator can enter commands, such as cooking temperature within cavity 12, cooking time, blower speed, etc., via first and second control panels 15, 16 to effectuate cooking controls on any food items placed within cavity 12.
With reference now to FIG. 2, there is depicted a cross-sectional view of housing 11, in accordance with a preferred embodiment of the present invention. As shown, housing 11 accommodates slider 20 having a first food loading section 21 and a 21 second food loading section 22. The surfaces of first and second food loading sections 21, 22 are substantially planar. First and second food loading sections 21, 22 are configured 23 to receive cooking plates 27, 28, respectively. Any food item intended to be cooked by matchbox oven 10 is initially placed on either one of cooking plates 27, 28. Cooking plates 27, 28 can be identical or different from each other, depending on the types of food items to be prepared. Thus, cooking plate 27 may be made of a different material and/or a different design from cooking plate 28.
Slider 20 also includes a first stopper 23, a second stopper 24 and a third stopper 25. Third stopper 25 serves as a divider between first and second food loading sections 21, 22 as well as an oven cover to prevent heat within cavity 12 from escaping through openings 18, 19. Along with third stopper 25, first and second stoppers 23, 24 serve as oven covers to prevent heat within cavity 12 from escaping through openings 18, 19, depending on the placement of slider 20 in relation to cavity 12. For example, first and third stoppers 23, 25 can serve as oven covers for first and second openings 18, 19, respectively. Similarly, third and second stoppers 25, 24 can serve as oven covers for first and second openings 18, 19, respectively.
Slider 20 is connected to a stepper motor (not shown) that powers the linear movement of slider 20 within cavity 12. Although slider 20 is moved by a stepper motor, it is understood by those skilled in the art that slider 20 can also be moved manually via a lever system or by a variety of other motorized movement designs.
In addition, housing 11 also contains a top plenum 35 and a bottom plenum 38. Top plenum 35 is connected to a top nozzle plate 34. Bottom plenum 38 is connected to a bottom nozzle plate 37. Top nozzle plate 34, top plenum 35, bottom nozzle plate 37 and bottom plenum 38 are part of the heating and airflow system for matchbox oven 10 such that heated air in top plenum 35 and bottom plenum 38 are in gaseous communication with cavity 12 through top nozzle plate 34 and bottom nozzle plate 37, respectively. Top nozzle plate 34 and bottom nozzle plate 37 include multiple conical shape nozzles for directing hot pressured airstream towards any food items placed on the portion of slider 20 located within cavity 12. Although air passes through top nozzle plate 34 and bottom nozzle plate 37 into cavity 12, it is understood by those skilled in the art that top plenum 35 or bottom plenum 38 could be in gaseous communication with cavity 12 via a variety of air opening configurations such as tubes, rectangular openings and the like. Moreover, air can enter cavity 12 through only one of top plenum 35 or bottom plenum 38.
For additional heating, an optional infrared radiation heating element 36 can be placed within cavity 12 somewhere between slider 20 and bottom nozzle plate 37 or between slider 20 and top nozzle plate 34 for supplying heat towards any food located on first loading section 21 or second loading section 22 of slider 20. Although an infrared radiation heating element is being used in the current embodiment, it is understood by those skilled in the art that other heating systems, such as microwave, steam or a combination thereof, are also applicable to the present invention.
Referring now to FIG. 3, there is depicted a diagram of the heating and airflow system within matchbox oven 10, in accordance with a preferred embodiment of the present invention. Air within cavity 12 is initially pumped in to a heater plenum 31 via an intake opening 30. Heater plenum 31 includes a heater 39. After it has been sufficiently heated by heater 39, the hot air is then directed to top plenum 35 via a top 14 blower 32 and to bottom plenum 38 via a bottom blower 33. The pressurized hot air formed within top plenum 35 is subsequently directed to cavity 12 via multiple nozzles located on top nozzle plate 34 (from FIG. 2). Similarly, pressurized hot air formed within bottom plenum 38 is subsequently directed to cavity 12 via multiple nozzles located on bottom nozzle plate 37 (from FIG. 2). Although heated air is shown to be sent to top air plenum 35 and bottom plenum 38 via separate blowers, it is understood by those skilled in the art that heated air can be sent to both top plenum 35 and bottom plenum 38 via a single blower.
With reference now to FIG. 4a, there is depicted a top view of slider 20, in accordance with a preferred embodiment of the present invention. As shown, slider 20, which includes first and second food loading sections 21-22 and stoppers 23-25, is supported by a first pair of rails 42, 43 and a second pair of rails 44, 45. The linear movement of slider 20 on top of rails 42, 43 is preferably powered by a stepper motor 41. The widths of stoppers 23-25, which are preferably the same, are wider than the thickness of openings 18, 19. Thus, two of stoppers 23-25 can serve as oven covers to prevent heat within cavity 12 from escaping through openings 18, 19, depending on the placement of slider 20 in relation to cavity 12. Although three stoppers 23-25 are shown in the preferred embodiment, it is possible to employ less than three stoppers on slider 20 at the expense of a higher heat loss from cavity 12.
With reference now to FIGS. 4b-4c, there are depicted two side views of slider 20, in accordance with a preferred embodiment of the present invention. In FIG. 4b, first food loading section 21 is shown to be located within cavity 12, with first and third stoppers 23, 25 positioned centrally within first and second openings 18, 19, respectively. In this position, first and third stoppers 23, 25 serve as oven covers for first and second openings 18, 19, respectively. In FIG. 4c, second food loading section 22 is shown to be located within cavity 12, with third and second stoppers 25, 24 positioned centrally within first and second openings 18, 19, respectively. In this position, third and second stoppers 25, 24 serve as oven covers for first and second openings 18, 19, respectively.
In FIGS. 4b-4c, stoppers 23-25 are shown to be positioned centrally within openings 18-19. However, during a cooking cycle, slider 20 can be moved to-and-fro slightly and repeatedly to allow the edges of two of stoppers 23-25 to flush with openings 18-19 of housing 11. Such movements are designed to avoid overheating of a food item at any spot located directly underneath a nozzle. The distance within which slider 20 can be moved to-and-fro is preferably dictated by the widths of stoppers 23-25 in order to avoid heat loss from cavity 12 during such movements.
Referring now to FIGS. 5a-5c, there are illustrated a method of cooking when only one of food loading sections 21, 22 of slider 20 is used, in accordance with a preferred embodiment of the present invention. An uncooked raw food item (RF) is initially placed on food loading section 22 (or 21), as shown in FIG. 5a. An operator then enters an appropriate cook settings for cooking the food item via control panel 16 (or 15), and food loading section 22 (or 21) is subsequently moved within cavity 12, as depicted in FIG. 5b. After a period of time has lapsed, food loading section 22 (or 21) exits cavity 12, and the fully cooked food item (CF) is ready to be removed from food loading section 22 (or 21) by an operator, as shown in FIG. 5c. 
With reference now to FIGS. 6a-6f, there are illustrated a method of cooking when both food loading sections 21, 22 of slider 20 are being used, in accordance with a preferred embodiment of the present invention. A first uncooked raw food item (RF-1) is initially placed on food loading section 22, and an operator then enters an appropriate cook setting for cooking the first food item via control panel 16, as shown in FIG. 6a. Food loading section 22 is subsequently moved inside cavity 12, as depicted in FIG. 6b. While the first food item is being cooked (F-1-C), a second uncooked raw food item (RF-2) can be placed on food loading section 21, and the operator enters an appropriate cook setting for cooking the second food item via control panel 15, as depicted in FIG. 6c. After a period of time has lapsed, food loading section 22 on which the first food item is fully cooked (CF-1) exits cavity 12 while food loading section 21 is moved inside cavity 12, as shown in FIG. 6d. While the second food item is being cooked (F-2-C), the fully cooked first food item (CF-1) is ready to be removed by the operator from food loading section 22, as shown in FIG. 6e. 
While the second food item is being cooked (F-2-C), a third uncooked raw food item (RF-3) can be placed on food loading section 22, and the operator enters an appropriate cook settings for cooking the third food item via control panel 16, as depicted in FIG. 6f. 
The above-mentioned sequence can be performed repeatedly for different food items. Since different cooking times can be entered by an operator, any of the above-mentioned food items can be completely different from each other.
As has been described, the present invention provides a matchbox oven for continuously and efficiently cooking a wider variety of food items while minimizing heat loss, resulting in improved energy efficiency.
While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope s of the invention.

## Claims

1. An oven comprising:
a housing having a cavity, the housing including a first opening and a second opening, the first opening and the second opening defining a cavity length;
a rigid surface for receiving items, the surface having a length greater than the cavity length, and a plurality of stoppers attached on the surface;
the surface configured to be moved to a position in the cavity such that a first stopper covers the first opening and a second stopper covers the second opening to prevent heat within the cavity from escaping through the first opening and the second opening; and
a mover operatively connected to the surface to linearly move the surface bidirectionally only in a single axis and a single plane, to cause items placed on the surface to be moved in and out of the cavity through at least one of the first opening and the second opening.

2. The oven of claim 1, wherein the first stopper is attached on a first end of the surface, a third stopper is attached on a second end of the surface, and the second stopper is attached on or near the middle of the surface between the first stopper and the third stopper.

3. The oven of claim 1, further including a heat source for providing heat to the cavity to heat an item placed on a portion of the surface located within the cavity.

4. The oven of claim 3, wherein the oven includes an air intake for receiving air from the cavity, and the heat source heats the air received from the air intake.

5. The oven of claim 3, wherein the oven includes a blower for returning heated air to the cavity.

6. The oven of claim 3, wherein the oven includes a first plenum and a first nozzle plate having at least one opening through which heated air enters the cavity, and the oven includes a second plenum and a second nozzle plate having at least one opening through which heated air enters the cavity.

7. The oven of claim 4, wherein the cavity includes an infrared radiation heating element.

8. The oven of claim 1, wherein a stepper motor moves the surface to-and-fro within a width of at least one of the first, second and third stoppers during a heating cycle.

9. An oven comprising:
a housing having a cavity and first and second openings;
a rigid surface that is movable only in a single axis and a single plane, a first portion of the surface is located substantially within the cavity when a second portion of the surface is located substantially outside the cavity, and the first portion of the surface is located substantially outside the cavity when the second portion of the surface is located substantially within the cavity; and
a plurality of stoppers attached onto the surface, wherein two of the stoppers substantially block the first and second openings, respectively, when one of the first and second portions of the surface is located within the cavity.

10. The oven of claim 9, further including a heat source for providing heat to the cavity to heat an item placed on one of the first and second portions of the surface located within the cavity.

11. The oven of claim 9, further including a controller for applying a first cook setting to the oven when the first portion of the surface is located within the cavity, and for applying a second cook setting to the oven when the second portion of the surface is located within the cavity, wherein the first cook setting and the second cook setting are independent of each other.

12. The oven of claim 11, wherein the controller comprises a first control panel for entering the first cook setting and a second control panel for entering the second cook setting.

13. The oven of claim 9, further comprising a mover operatively connected to the surface to linearly move the surface in and out of the cavity, wherein items placed on the first portion of the surface are moved in and out of the cavity through the first opening and items placed on the second portion of the surface are moved in and out of the cavity through the second opening.

14. The oven of claim 13, wherein the first portion of the surface comprises a first food loading section and the second portion of the surface comprises a second food loading section.

15. The oven of claim 13, wherein the mover moves the surface to-and-fro during a heating cycle.

16. A method for heating an item in an oven, the oven including a housing having a cavity with a first opening and a second opening, and a rigid surface including a first item loading section and a second item loading section, the method comprising:
moving the surface only in a single axis and a single plane for positioning the first item loading section in the cavity through the first opening and the second food loading section outside the cavity through the second opening;
blocking the first opening with a first stopper attached to the surface;
blocking the second opening with a middle stopper attached to the surface;
moving the surface only in the single axis and the single plane for positioning the first item loading section outside the cavity through the first opening and the second item loading section in the cavity through the second opening;
blocking the first opening with the middle stopper attached to the surface; and
blocking the second opening with a second stopper attached to the surface.

17. The method of claim 16, further including providing heat to the cavity for heating an item placed on one of the first item loading section and the second item loading section located within the cavity.

18. The method of claim 17, further including controlling the heat by a first cook setting of the oven when the first item loading section is within the cavity and by a second cook setting of the oven when the second item loading section is within the cavity.

19. The method of claim 18, further comprising entering the first cook setting on a first control panel and entering a second cook setting on a second control panel.

20. The method of claim 16, further including moving the surface to-and-fro during a heating cycle.

21. The method of claim 16, further including heating the cavity using an infrared radiation heating element.