Convection furnace

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The priority of this application is claimed by the filing date of US patent application No. 15/094,645 filed April 8, 2016, the filing date of US patent application No. 15/016,093 filed February 4, 2016, and the filing date of the patent application US No. 14/733,533, filed June 8, 2015, the entire contents of which are incorporated herein by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to cooking stoves in general and, in particular, to a convection oven with one or more removable air chambers.

BACKGROUND OF THE INVENTION

[0003] An oven typically has an interior configured to accommodate food products for cooking. The oven also contains a heating element, which can be an electric resistance or a gas burner, to receive thermal energy for the preparation of any food products placed in the interior of the oven. Some ovens may include a fan to force heated air into the interior of the oven, and these ovens are commonly referred to as convection ovens.

[0004] Convection ovens have been most prevalent in industrial kitchens for decades. Industrial convection ovens are usually available in two sizes, namely: full-sized and half-sized. Full-size industrial convection ovens are designed to occupy a standard workspace that is approximately 40 inches (approximately 1 meter) wide and 40 inches (1 meter) deep, which is available for full-size convection ovens in most industrial kitchens. The interior of full-sized industrial ovens also has dimensions that can accommodate standard baking sheets that are approximately 26 inches (65 cm) wide and 18 inches (45 cm) deep. The height of the interior of the oven is usually about 20 inches (50 cm), which can be configured to accommodate shelves of several heights, such as shelves 11 of possible heights, to match the heights of various products that can be cooked in a convection oven. For example, only two racks can be placed in an industrial convection oven if a turkey is cooked with a 9-inch (22.5 cm) carcass height, while 4 to 5 racks can be evenly distributed from top to bottom when many cooking racks are used 2 centimeter lasagna. Half-sized industrial convection ovens are similarly designed and designed so that they meet the industrial standards of half-sized spaces in industrial kitchens and can accommodate industrial standard half-sized baking sheets.

[0005] When cooking in a typical convection oven, heated air in the interior of the oven is circulated by a fan. A fan typically initiates a stream of heated air by drawing air from the interior of the furnace through one or more air return openings on the rear wall of the interior of the furnace. Heated air then leaves other openings on the side walls of the interior or openings on the upper or lower walls of the interior of the furnace. Heated air moves through the interior of the oven to help distribute thermal energy to food items located in the interior of the oven. An example of a heating system of a typical convection oven can be found in US Pat. No. 4,395,233, issued to Smith et al.

[0006] One problem with the heating system of a conventional convection oven is that it can generate regions with high and low air flow rates in the interior of the oven, so that heated air is distributed unevenly in the interior of the oven. As a result, food products placed in the interior of the oven may not be cooked uniformly. For example, foods placed on different shelves at different heights in a convection oven can be cooked at different speeds. In addition, foods placed on the same rack may also not receive uniform heating. This uneven cooking can lead to food waste, since food products located in areas with a higher internal temperature of the oven may be unacceptably overcooked compared to food products located in parts with lower heat. Uneven cooking can be partially overcome by turning the baking sheets in the interior of the oven, as well as using lower cooking temperatures and air blower speeds, but this increases the requirements for labor qualification, as well as cooking time.

[0007] Therefore, there is a need for an improved convection oven that can eliminate the above problems.

SUMMARY OF THE INVENTION

[0008] It has been found that the above and related objects of the present invention are obtained in the form of several related aspects, including a convection oven having one or more air chambers.

[0009] The present invention relates to a convection oven, comprising a housing having an interior space and a door for accessing the interior of the oven, a left side air channel located on a left side wall of the interior of the furnace, a right side air channel located on a right side wall of the interior oven spaces an air blower for supplying heated air to the left side air channel and the right side air channel and an intermediate air chamber defining a lower part of the upper cooking chamber and an upper part of the lower cooking chamber in the interior of the oven.

[0010] The intermediate air chamber has a left side air inlet configured to receive part of the heated air from the left side air channel, a right side air inlet configured to receive part of the heated air from the right side air channel, an upper surface, bounding the upper part of the inner space of the intermediate air chamber and having upper air outlets, which are configured to direct a portion of the heated air entering through the left side air inlet and the right side air inlet upward into the upper cooking chamber, and the lower surface defining the lower part of the interior of the intermediate air chamber and having lower outlet openings for air, which is configured to direct part of the heated air, entering through the left side air inlet and the right side air inlet, down into the lower cooking chamber.

[0011] In at least one embodiment, the upper air outlet openings and the lower air outlet openings of the intermediate air chamber are offset from each other.

[0012] In at least one embodiment, the intermediate air chamber further has a front surface and a rear surface, wherein both the front and rear surfaces are substantially impervious to air, so that any airflow through the front or rear is substantially prevented. surface.

[0013] In at least one embodiment, at least one of the upper surface and lower surface of the intermediate air chamber is curved.

[0014] In at least one embodiment, the upper surface of the air chamber and the lower surface of the air chamber are curved towards each other so that that the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the left side air inlet is substantially equal to the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the right side air inlet, and the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the left side air inlet or at the right side air inlet is greater than the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the midpoint of the intermediate air cameras.

[0015] In at least one embodiment, the front cross section of the upper surface and lower surface of the intermediate air chamber contains two essentially hyperbolic curves.

[0016] In at least one embodiment, an intermediate air chamber comprising two hyperbolic curved surfaces as upper and lower surfaces is configured to be removed from the interior of the furnace.

[0017] In at least one embodiment, the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the right side air inlet or at the left side air inlet is from 1.5 inches to 3.0 inches ( from 3.75 cm to 7.5 cm), and the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the midpoint of the intermediate air chamber is from 0.25 inches to 1.25 inches (from 0.62 cm to 3.12 cm).

[0018] In at least one embodiment, both the front and rear width of the intermediate air chamber is from 20 to 30 inches (50 cm to 75 cm), and the length of both the left and right side of the intermediate air chamber is 15 inches to 25 inches (25 cm to 62.5 cm).

[0019] In at least one embodiment, the left side air inlet is directly connected to the left side air channel, and the right side air inlet is constantly connected to the right side air channel.

[0020] In at least one embodiment, the left side air inlet is detachably connected to the left side air channel, and the right side air inlet is detachably connected to the right side air channel.

[0021] In at least one embodiment, both the left side air channel and the right side air channel are configured to close with a shutter if it is not connected to a corresponding one of the left side air inlet and the right side air inlet.

[0022] In at least one embodiment, the intermediate air chamber is configured to be removed from the interior of the furnace.

[0023] In at least one embodiment, said upper surface of the intermediate air chamber is configured to support a food rack for the upper cooking chamber.

[0024] In at least one embodiment, the convection oven has an air return opening located on a rear wall of the interior of the oven.

[0025] In at least one embodiment, the convection oven further comprises an upper left side air channel located on a left side wall of the interior space near the upper part of the furnace interior and configured to receive a portion of the heated air from the air blower, an upper right side air channel , located on the right side wall of the inner space near the upper part of the inner space of the furnace and configured to receive part of the heated air from the air blower, and the upper air chamber located in the upper part of the inner space of the furnace. The upper air chamber has a left side air inlet configured to receive part of the heated air from the upper left side air channel, a right side air inlet made to receive part of the heated air from the upper right side air channel, an upper surface bounding the upper part of the inner space of the upper air chamber, and the lower surface, bounding the lower part of the inner space of the upper air chamber and having air outlets that are configured to direct heated air entering through the left side air inlet and right side air inlet down into the interior of the furnace.

[0026] In at least one embodiment, the upper air chamber is configured to be removed from the interior of the furnace.

[0027] In at least one embodiment, the upper surface of the upper air chamber is flat and the lower surface of the upper air chamber is curved.

[0028] In at least one embodiment, the vertical distance between the upper surface and the lower surface of the upper air chamber at the left side air inlet is substantially equal to the vertical distance between the upper surface and the lower surface of the upper air chamber at the right side air inlet for air and the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the left side air inlet or at the right side air inlet is greater than the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the midpoint of the upper air cameras.

[0029] In at least one embodiment, the convection oven further comprises a lower left side air channel located on a left side wall of the interior space near the lower part of the furnace interior and configured to receive part of the heated air from the air blower, a lower right side channel, located on the right side wall of the inner space near the lower part of the inner space of the furnace and configured to receive part of the heated air from the air blower, and the lower air chamber located in the lower part of the inner space of the furnace. The lower air chamber has a left lateral air inlet configured to receive part of the heated air from the lower left side air channel, a right side air inlet configured to receive part of the heated air from the lower right side air channel, an upper surface bounding the upper part of the inner space of the lower air chamber and having exhaust openings for air, moreover, the air outlets are configured to direct heated air entering through the left side air inlet and the right side air inlet upward into the interior of the furnace, and the lower surface forming the lower part of the inner space of the lower air chamber.

[0030] In at least one embodiment, the lower air chamber is configured to be removed from the interior of the furnace.

[0031] In at least one embodiment, the upper surface of the lower air chamber is curved, and the lower surface of the lower air chamber is flat.

[0032] In at least one embodiment, the vertical distance between the upper surface and the lower surface of the lower air chamber at the left side air inlet is substantially equal to the vertical distance between the upper surface and the lower surface of the lower air chamber at the right side air inlet air and the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the left side air inlet or at the right side air inlet is greater than the vertical distance between the upper surface of the air chamber and the lower surface of the air chamber at the midpoint of the lower air cameras.

[0033] In at least one embodiment, the upper surface of the lower air chamber is configured to support a food rack.

[0034] Features, functions and advantages may be achieved independently in various embodiments of the invention, or may be combined in other embodiments in which further details can be seen with reference to the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The following detailed description, given by way of example and not intended to limit the present invention, is best understood in conjunction with the accompanying drawings, in which:

[0036] FIG. 1 is a perspective view of a convection oven in accordance with an illustrative embodiment of the invention,

[0037] FIG. 2A is a front perspective view of the interior of the convection oven shown in FIG. 1, without air chambers disposed therein, in accordance with an illustrative embodiment of the invention,

[0038] FIG. 2B is a front perspective view of the interior of the furnace shown in FIG. 2A filled with air chambers in accordance with an illustrative embodiment of the invention.

[0039] FIG. 3A-3D depict various cross-sectional views of the interior of an oven filled with air chambers inside the convection oven shown in FIG. 1, in accordance with an illustrative embodiment of the invention.

[0040] FIG. 3E-3F depict illustrative airflow directions in the interior of the convection oven shown in FIG. 1.

[0041] FIG. 4A-4D depict front views, respectively, in a perspective view, top, side, in a perspective view and in front of a section of an intermediate air chamber made in accordance with an illustrative embodiment of the invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0042] In the present description, like reference numerals refer to like elements in the drawings, which illustrate various illustrative embodiments of the present invention.

[0043] In the drawings, and in particular in FIG. 1 is a perspective view of a convection oven in accordance with an illustrative embodiment of the present invention. As shown, the convection oven 10 comprises a housing having an upper panel 11, a lower panel 12, a rear panel 13, and two side panels 14a, 14b.

[0044] A pair of oven doors 15a, 15b may form a front panel of the cabinet and is pivotally connected to the side panels 14a, 14b, respectively, by hinges. The doors 15a and 15b may include handles 16a and 16b, respectively, for opening and closing them, and a latch may be provided to hold the doors 15a, 15b in the closed position. Door sensors (not shown) can be used to determine when doors 15a, 15b open or close.

[0045] In alternative embodiments, instead of a pair of doors, the furnace may comprise one door (not shown) that is pivotally connected to one of the side panels 14a, 14b, the upper panel 11 or the lower panel 12 through hinges, or one or more lower swing doors ( also not shown).

[0046] The convection oven 10 also includes a control panel 18, which may be configured with one or more control knobs, one or more touch screens, or using a combination of control knobs and touch screen technology. The operator can enter commands or cooking parameters, such as cooking temperature, cooking time, fan speed, etc. through the control panel 18 to implement the cooking control on any food products placed in the convection oven 10.

[0047] FIG. 2A-2B and 3A-3D depict various views of the interior space 20 of the furnace 10 in accordance with an illustrative embodiment of the invention.

[0048] FIG. 2A is a front perspective view of an interior space 20 of a furnace in which there are no air chambers disposed therein. The inner space 20 is limited by the upper wall 21, the lower wall 22, the rear wall 23 and the left and right side walls 24a and 24b together with the doors 15a, 15b (shown in Fig. 1). The size of the interior space 20 of the furnace, designed for the "full-sized" market, may be approximately 10 cubic feet (0.28 cubic meters), in accordance with an illustrative embodiment of the invention. Different sizes will be applied to the interior of the furnace in a smaller or larger furnace. On both side walls 24a, 24b of the interior space there are several parallel rails 25a, 25b, configured to support the placement of one or more air chambers in the interior space 20 of the furnace.

[0049] Also, on the left 24a and right 24b side walls of the interior, there are one or more air channels for supplying heated air from one or more air blowers 19 (see, for example, Fig. 3D and 3E) of the furnace 10 in interior space 20. As shown in FIG. 2A and 3A-3B, the left side wall 24a of the inner space comprises left side air channels 26a, 27a, 28a, 29a that are parallel to each other and spaced apart vertically from each other by a certain distance. Similarly, the right side wall 24b of the inner space contains right side air channels 26b, 27b, 28b, 29b, which are parallel to each other and spaced vertically from each other by a certain distance. Preferably, the left side air channels 26a, 27a, 28a, 29a and the right side air channels 26b, 27b, 28b, 29b are symmetrically placed on the left and right side walls 24a, 24b of the interior so that, as further described below, the air chamber, placed in the interior space 20 of the furnace can receive heated air from a pair of left and right side air channels located essentially at the same vertical height (for example, (26a and 26b), (27a and 27b), (28a and 28b), (29a and 29b)) through its left and its right sides. Preferably, the size of each of the left side air channels 26a, 27a, 28a, 29a is substantially the same as the size of its paired right side air channel 26b, 27b, 28b, 29b.

[0050] FIG. 2A shows that each of the left and right side air channels 26a, 27a, 28a, 29a, 26b, 27b, 28b, 29b may have one horizontally elongated rectangular opening. In alternative embodiments, each air passage may take a different shape or shape, such as a plurality of rectangular or circular holes or openings of other shapes.

[0051] In FIG. 2A also shows an air return hole 30 located on the rear wall 23 of the interior space 20 of the furnace (see also FIG. 3D).

[0052] FIG. 2B and 3A-3C show that the interior of the furnace 20 can be filled with one or more air chambers. In FIG. 2B is a front perspective view of an interior space 20 of a furnace filled with an upper air chamber 121, a lower air chamber 129, and one or more intermediate air chambers 127, 128. FIG. 3A-3C are frontal cross-sectional views of air chambers 126, 127, 128, and 129 placed in the interior of the furnace 20. In FIG. 3A-3B also show partial views of the right side air channels 26b, 27b, 28b, 29b in the right side interior wall 24b, and partial views of the left side air channels 26a, 27a, 28a, 29a in the left side wall 24a of the furnace interior space 20.

[0053] As shown in FIG. 2B, the intermediate air chambers 127, 128 divide the interior of the oven 20 into several cooking chambers 226, 227, 228 (for example, three in this case). The upper air chamber 126 and the intermediate air chamber 127 limit, respectively, the upper and lower parts of the chamber 226, the intermediate air chamber 127 and the intermediate air chamber 128 limit, respectively, the upper and lower parts of the chamber 227, and the intermediate air chamber 128 and the lower air chamber 129 limit, respectively, the upper and lower parts of the chamber 228. In accordance with an illustrative embodiment of the present invention, the size of at least one of these chambers 226, 227, 228 for an oven designed for a “full-size market” may range from 1.5 to 2.0 cubic feet (0.042 to 0.057 cubic meters). Different sizes will be used for cooking chambers in small or large ovens.

[0054] Each of the air chambers 126, 127, 128, 129 has a front surface 126g, 127g, 128g, 129g (see Fig. 2B), a rear surface 126h, 127h, 128h, 129h (see Fig. 3C), the upper surface 126c, 127c, 128c, 129c (see Fig. 3A), lower surface 126d, 127d, 128d, 129d (see Fig. 3B), a left side having left side inlets 126a, 127a, 128a, 129a for air (see Fig. 3A), and a right side having right lateral air inlets 126b, 127b, 128b, 129b (see FIG. 3B), all of which define an outer surface and an inner space of the air chamber. Preferably, the front and rear surfaces of each air chamber 126, 127, 128, 129 are substantially impervious to air, so that air does not pass through them.

[0055] When each of the air chambers 126, 127, 128, 129 is placed in the interior space 20 of the furnace, the front surface 126g, 127g, 128g, 129g of the air chamber 126, 127, 128, 129 faces the doors 15a, 15b, and the rear surface 126h, 127h, 128h, 129h facing the rear wall 23 of the inner space 20.

[0056] As shown in FIG. 2B and 3A-3C, the intermediate air chambers 127, 128 may be substantially identical to each other in design. In alternative embodiments, each of the intermediate air chambers may have a structure different from that of the other intermediate air chamber.

[0057] As shown in FIG. 3A-3B, a left side air inlet 126a of the upper air chamber 126 is connected or placed adjacent to a left side air channel 26a located on the left side wall 24a of the interior space 20, and a right side air inlet 126b of the upper air chamber 126 is connected or located next to the right side air channel 26b located on the right side wall 24b of the inner space 20 so that the heated air, flowing from the left and right side air channels 26a, 26b can enter the interior of the upper air chamber through, respectively, the left and right side air inlets 126a, 126b.

[0058] As also shown in FIG. 3A-3B, the left side air inlet 127a for the intermediate chamber 127 is connected or placed adjacent to the left side air channel 27a located on the left side wall 24a of the furnace interior space 20, and the right side air inlet 127b for the intermediate chamber 127 is connected or placed next to the right side air channel 27b located on the right side wall 24b of the inner space 20 so that the heated air, flowing from the left and right side air channels 27a, 27b can enter the interior of the intermediate chamber 127 through the left and right side air inlets 127a, 127b, respectively. Similarly, the left side air inlet 128a of the intermediate chamber 128 is connected or placed adjacent to the peripheral air channel 28a located on the left side wall 24a of the interior space 20, and the right side air inlet 128b of the intermediate chamber 128 is connected or placed adjacent to the peripheral an air channel 28b located on the right side wall 24b of the inner space 20 so that the heated air, flowing from the left and right side air channels 28a, 28b may enter the interior of the intermediate air chamber 128 through the left and right side air inlets 128a, 128b, respectively.

[0059] As also shown in FIG. 3A-3B, the left side air inlet 129a for the lower air chamber 129 is connected or placed adjacent to the left side air channel 29a located on the left side wall 24a of the interior space 20, and the right side air inlet 129b for the lower air chamber 129 is connected or located next to the right side air channel 29b located on the right side wall 24b of the inner space 20 so that the heated air, flowing from the left and right side air channels 29a, 29b, can enter the interior of the lower air chamber 129 through the left and right side air inlets 129a, 129b, respectively.

[0060] Each of the air chambers 126, 127, 128, 129 may be configured to be removed from the interior of the furnace 20. In this case, the left and right side air inlets 126a, 126b for the upper air chamber 126 are detachably connected to the left and right side air channels 26a, 26b, the left and right side air inlets 127a, 127b for the intermediate air chamber air 127 are detachably connected, respectively, to the left and right side air channels 27a, 27b, the left and right side inlets 128a, 128b for the air of the intermediate air chamber 128 are detachably connected respectively to the left and right side air channels 28a, 28b, and the left and right side air inlets 129a, 129b for the air of the lower air chamber 129 are detachably connected to the left and right side air channels 29a, 29b. In addition, each of the left and right side air channels 26a, 27a, 28a, 29a, 26b, 27b, 28b, 29b is configured to close with a shutter (not shown) if the corresponding air chamber is removed from the inner space 20 and is no longer connected to air channel.

[0061] In alternative embodiments, some or all of the air chambers 126, 127, 128, 129 may be permanently attached to the interior of the furnace 20. In this case, the left and right side air inlets 126a, 126b for the air of the upper air chamber 126 can be detachably or permanently connected to the left and right side air channels 26a, 26b, the left and right side inlets 127a, 127b for the air of the intermediate air chamber 127 can be detachably or permanently connected, respectively, to the left and right side air channels 27a, 27b, the left and right side air inlets 128a, 128b for the intermediate air chamber 128 can be detachably or permanently connected to the left and right side air channels 28a, 28b, and the left and right side air inlets 129a, 129b for lower air air chambers 129 may be detachably or permanently connected, respectively, to the left and right side air channels 29a, 29b. For example, the upper and lower air chambers 126, 129 may be permanently attached to the interior of the furnace 20, while the intermediate air chambers 127, 128 may be removable from the interior of the space 20.

[0062] If the intermediate chambers 127, 128 are configured to be removed from the inner space 20, then the number and size of the cooking chambers in the inner space 20 can be changed or adjusted by removing one or more intermediate air chambers from the inner space 20. For example, by removing the intermediate air chamber 128, the inner space 20 has a relatively large cooking chamber at the bottom (with a combined space for chambers 227 and 228) and a smaller chamber 226.

[0063] As shown in FIG. 3A-3B, the size and shape of each of the left side air inlets 126a, 127a, 128a, 129a for air of the air chambers 126, 127, 128, 129 may substantially correspond to the size and shape of the corresponding left side air channel 26a, 27a, 28a, 29a from which the left side air inlet receives heated air. Similarly, the size and shape of each of the right side air inlets 126b, 127b, 128b, 129b may substantially correspond to the size and shape of the corresponding right side air channel 26b, 27b, 28b, 29b from which the right side air inlet gets heated air.

[0064] In alternative embodiments, the size of each of the left and right side air inlets for the air chambers may be smaller or larger than the size of the air passage from which the lateral air inlet receives heated air. In other alternative embodiments, the shape of each of the left and right side air inlets for the air chambers may differ from the shape of the air channel from which the lateral air inlet receives heated air. For example, the air channel on the side wall of the interior space 20 may have round holes, while the corresponding side air inlet for the air in the air chamber may have the form of an elongated rectangular hole.

[0065] As shown in FIG. 3A-3C, the air chambers 126, 127, 128, 129 may be positioned relative to the left and right side walls 24a, 24b in the interior space 20 of the furnace so that heated air coming from the left side air channels 26a, 27a, 28a, 29a and the right lateral air channels 26b, 27b, 28b, 29b, cannot flow into the interior space 20 in any other way than through the air chambers 126, 127, 128, 129.

[0066] In alternative embodiments, the left and right side walls 24a and 24b in the interior space 20 of the furnace may have additional separate holes (not shown) to provide additional airflow into the interior space 20 from the left and right sides.

[0067] As shown in FIG. 3A-3B, each intermediate air chamber 127, 128 may be configured to direct heated air up and down. The upper surface 127c of the intermediate air chamber 127 has upper air outlets 127e for air that are configured to direct part of the heated air coming from the left and right side air channels 27a, 27b through the left and right side air inlets 127a, 127b up into camera 226. The lower surface 127d of the intermediate air chamber 127 has air outlets 127f that are configured to direct part of the heated air coming from the left and right side air channels 27a, 27b through the left and right side air inlets 127a, 127b down into the chamber 227.

[0068] Similarly, the upper surface 128c of the intermediate chamber 128 has upper air outlets 128e that are configured to direct part of the heated air from the left and right side air channels 28a, 28b through the left and right side inlets 128a, 128b for air up into the chamber 227. The lower surface 128d of the intermediate air chamber 128 has air outlets 128f that are configured to direct part of the heated air coming from the left and right side air channels 28a, 28b through the left and right side air inlets 128a, 128b down into the chamber 228.

[0069] On the other hand, the upper air chamber 126 and the lower air chamber 129 are configured to direct heated air in only one direction, up or down. The bottom surface 126d of the upper air chamber 126 has lower air outlets 126f for directing heated air from the left and right side air channels 26a, 26b through the left and right side air inlets 126a, 126b down into the chamber 226 . The upper surface 129 from the lower air chamber 129 has upper air outlets 129e that are configured to direct heated air coming from the left and right air channels 29a, 29b through the left and right side air inlets 129a, 129b up into the chamber 228 .

[0070] FIG. 3D is a top sectional view of the interior of the furnace 20, showing the upper surface 127 from the air chamber and the upper air outlets 127e for the intermediate air chamber. In FIG. 3D shows an illustrative supply air path through which the supply air exits the air blower 19 and flows through both the left supply path 40a and the right supply path 40b until it reaches the air channels (e.g., the right side air channel 27b) located on left and right side walls 24a, 24b of the interior space 20 of the furnace. As shown in FIG. 3C-3D, the rear channel wall 33 and the left and right channel side walls 34a, 34b of the convection oven 10 surround the inner space 20. The left supply duct 40a is limited by portions of the rear channel wall 33 and the rear wall 23 of the inner space located to the left of the air blower 19, the side wall 34 a of the left channel and the left side wall 24 a of the inner space. The right intake path 40b is limited by portions of the rear channel wall 33 and the rear wall 23 of the inner space located to the right of the air blower 19, the side wall 34b of the right channel and the right side wall 24b of the inner space.

[0071] FIG. 3D also shows an illustrative air return path from the interior of the furnace 20 to the air blower 19 through the air return hole 30 located on the rear wall 23 of the interior of the furnace 20.

[0072] In FIG. 3E-3F show the airflow directions (indicated by arrows) when the convection oven 10 shown in FIG. 3A-3D, operates in accordance with an illustrative embodiment of the present invention. As shown in FIG. 3E, one or more air blowers 19 in the convection oven 10 direct heated air to the left and right supply ducts 40a and 40b, and the heated air reaches the left and right side air channels 26a, 27a, 28a, 29a, 26b, 27b, 28b, 29b located on the left and right side walls 24a, 24b of the interior space 20 of the furnace. Heated air then enters the interior of the air chambers 126, 127, 128, 129 through the left and right side air channels 26a, 27a, 28a, 29a, 26b, 27b, 28b, 29b.

[0073] As shown in FIG. 3F, the upper air chamber 126 receives heated air from the left and right side air channels 26a, 26b through the left and right side air inlets 126a, 126b, and then directs the heated air downward into the chamber 226 through the lower air outlets 126f in the lower surface 126d of the air chamber.

[0074] The intermediate air chamber 127 receives heated air from the left and right side air channels 27a, 27b through the left and right side air inlets 127a, 127b, and then (1) directs a portion of the heated air upward into the chamber 226 through the upper air outlets 127e for the air in the upper surface 127c of the air chamber and (2) directs a portion of the heated air downwards into the chamber 227 through the lower air outlets 127f for the air in the lower surface 127d of the air cameras.

[0075] The intermediate air chamber 128 receives heated air from the left and right side air channels 28a, 28b through the left and right side air inlets 128a, 128b, and then (1) directs a portion of the heated air upward into the chamber 227 through the upper air outlets 128e for the air in the upper surface 128c of the air chamber and (2) directs a portion of the heated air downwards into the chamber 228 through the lower air outlets 128f for the air in the lower surface 128d of the air cameras.

[0076] The lower air chamber 129 receives the heated air from the left and right side air channels 29a, 29b through the left and right side air inlets 129a, 129b, and then directs the heated air upward into the chamber 228 through the upper air outlets 129e to upper surface 129c of the air chamber.

[0077] Thus, the heated air changes its direction from a generally horizontal path to a generally vertical path when it passes through air chambers 126, 127, 128, 129 and enters chambers 226, 227, 228 in the inner furnace space 20, as shown in FIG. 3F.

[0078] FIG. 3E shows that air in the interior space 20 of the furnace can be returned to the air blower 19 through the air return hole 30 located on the rear wall 23 of the interior space 20.

[0079] Preferably, the interior of each of the air chambers 126, 127, 128, 129 is shaped to facilitate uniform distribution of the heated air entering the interior of the furnace 20. For example, as shown in FIG. 3A-3C, the upper surface 127c, 128c and the lower surface 127d, 128d of the intermediate air chamber 127, 128, which limit, respectively, the upper and lower parts of the inner space of the intermediate air chamber, can be formed in such a way as to optimize the uniform distribution of the heated air stream into the interior 20. Similarly, the lower surface 126d of the upper air chamber 126 and the upper surface 129c of the lower air chamber 129 can be formed so as to optimize the uniform distribution of the heated air flow into the interior space 20.

[0080] According to the illustrative embodiment shown in FIG. 3A-3C, each of the upper surfaces 127c, 128c and the lower surfaces 127d, 128d of the intermediate air chamber 127, 128, the lower surface 126d of the upper air chamber 126 and the upper surface 129c of the lower air chamber 129 may be curved so that (1) the distance along vertical between the upper surface 126c, 127c, 128c, 129c and the lower surface 126d, 127d, 128d, 129d at the left side air inlet 126a, 127a, 128a, 129a for each air chamber 126, 127, 128, 129 is substantially equal to the vertical distance between the upper surface 126c, 127c, 128c, 129c and the lower surface 126d, 127d, 128d, 129d at the right side air inlet 126b, 127b, 128b, 129b for air, and (2) the distance along vertical between the upper surface 126c, 127s, 128s, 129c of the air chamber and the lower surface 126d, 127d, 128d, 129d of the air chamber at the left side air inlet 126a, 127a, 128a, 129a for air more, than the vertical distance between the upper surface 126c, 127c, 128c, 129c and the lower surface 126d, 127d, 128d, 129d at the midpoint of the air chamber 126, 127, 128, 129.

[0081] For example, as shown in FIG. 3A-3C (as well as in FIG. 40), the upper surface 127c, 128c and the lower surface 127d, 128d of the intermediate air chamber 127, 128 may be shaped so that the front cross section contains two essentially hyperbolic curves that are curved in the opposite direction friend at the midpoint of the intermediate air chamber.

[0082] FIG. 4A-4D depict various views of an intermediate air chamber 128 in accordance with an illustrative embodiment of the present invention. In FIG. 4A is a front perspective view of an intermediate air chamber 128 having substantially airtight front and rear surfaces 128g, 128h, an upper surface 128c having upper air outlets 128e, a lower surface 128d having lower air outlets 128f, left a side air inlet 128a and a right side air inlet 128b.

[0083] FIG. 4B is a plan view of the intermediate air chamber 128 showing the upper surface 128c of the air chamber having upper air outlets 128e. Preferably, the lower surface 128d of the intermediate air chamber 128 has substantially the same structure as the upper surface 128c of the air chamber. In this case, FIG. 4B may be a lower planar view of an intermediate air chamber 128 showing a lower surface 128d having lower air outlets 128f. As an example, the size of each upper air outlet 128e (or lower air outlet 128f) may be from 1.25 to 2.5 square inches (8 to 16.1 square centimeters). Although each of the upper air outlets 128e (or the lower air outlets 128f) shown in FIG. 4B has a substantially rectangular shape, in alternative embodiments it can have another shape, such as a square, circle, ellipse, rhombus, trapezoid, hexagon, or other type of regular or irregular geometric shape.

[0084] FIG. 4C is a side elevational view of the intermediate air chamber 128 as viewed from the right side air inlet 128b. The upper surface of the air chamber 128c and the lower surface of the air chamber 128d are curved towards each other at the midpoint of the intermediate air chamber 128, and the upper air outlets 128e and the lower air outlets 128f are partially visible. As shown in FIG. 4C, the locations of the upper air outlets 128e and the lower air outlets 128f can be offset from each other, so that the air changing its direction from horizontal to upward can be repelled from the solid bottom surface 128d of the air chamber, and likewise, air, changing its direction from horizontal to descending, it can be repelled from the continuous upper surface 128c of the air chamber. If the locations of the upper air outlets 128e and the lower air outlets 128f are aligned with each other, then the air moving up through the upper air outlets 128e will be repelled from the air moving downward through the lower air outlets 128f. By shifting the arrangement of the upper air outlets 128e and the lower air outlets 128f of the intermediate air chamber 128, an increased air speed can be achieved, resulting in a reduction in cooking time.

[0085] FIG. 4D is a front cross-sectional view of the intermediate air chamber 128, showing a cross section of the upper surface 128c of the air chamber and the lower surface 128d of the air chamber, forming two substantially hyperbolic curves that are curved towards each other at the midpoint 128i of the intermediate air chamber 128. This configuration optimizes the uniform distribution of the heated air flow into the interior of the furnace, forcing the heated air entering through the left and right side air inlets 128a, 128b into the narrower interior when it approaches the middle 128i of the intermediate air chamber 128.

[0086] In accordance with an illustrative embodiment of the invention, the front and rear width of the intermediate air chamber 128 for the furnace, designed for the "full-sized" market, can be from 20 to 30 inches (from 50.8 to 76.2 centimeters) (for example, 26.8 inches (68 centimeters)). The length of the right and left sides of the intermediate air chamber 128 (for example, the horizontal width of the left / right side air inlet 128a, 128b) for a furnace intended for the “full-size” market can be from 15 to 25 inches (from 38.1 to 63.5 centimeters) (e.g. 21 inches (53.3 centimeters)). For the width of the front and rear sides and the length of the right and left side of the intermediate air chamber for furnaces of larger or smaller sizes, various sizes are used.

[0087] Furthermore, the vertical distance between the upper surface 128c and the lower surface 128d of the intermediate chamber 128 at the left side air inlet 128a and the right side air inlet 128b (for example, the vertical height of the left side air inlet 128a / right lateral air inlet 128b) for a furnace intended for a “full-sized” market, may have a value in the range of 1.5 to 3 inches (3.8 to 7.6 centimeters) (e.g. 2 inches (5.1 centimeters)), and the vertical distance between the upper surface 128c of the air chamber and the lower surface 128d the air chamber in the middle 128i of the intermediate air chamber 128 for such a furnace may range from 0.25 inches to 1.25 inches (0.64 to 3.18 centimeters) (e.g. 0.7 inches (1.78 centimeters) ) Different sizes will be used for the vertical distance between the upper surface and the lower surface of the intermediate air chamber in smaller or larger furnaces.

[0088] As described above, the present invention provides an improved convection oven providing a more uniform flow of heated air in the interior of the oven.

[0089] Although the present invention has been described in conjunction with the illustrative embodiments described above and illustrated in the drawings, it is obvious that many alternatives, modifications, and changes in form and detail will be apparent to those skilled in the art. Accordingly, illustrative embodiments of the invention, as described above, are intended to illustrate and not to limit, and the nature and scope of the present invention should be construed broadly and limited only by the attached claims, and not the above description.