Dough proofing apparatus and related methods

A dough proofing apparatus includes a proofing chamber for holding dough during proofing operations and having a door for accessing the proofing chamber. An air duct assembly includes at least one inlet opening and at least one fan for drawing in air from the proofing chamber. At least one heating element is located within the air duct assembly for heating the air and a flow path for delivering the heated air back to the proofing chamber. A vent chamber is divided into an exhaust side and an intake side, the exhaust side fluidly connected to the air duct assembly, the intake side fluidly connected to the proofing chamber.

TECHNICAL FIELD

This application relates generally to cabinets utilized for proofing dough (i.e., allowing the dough to rise), and more particularly to a dough proofing cabinet with an improved air flow system and arrangement for controlling cabinet humidity.

BACKGROUND

It is known to provide dough proofers of the types shown in U.S. Pat. No. 6,894,252 in which a dough proofing apparatus has a chamber for holding dough, a chamber panel including a plurality of openings distributed thereon and a heating element located outside the chamber, with an upper air flow path from the heating element back to the chamber and a lower air flow path from the heating element back to the chamber. Blowers in the form of axial fans located centrally along a height of the panel operate to cause air flow from the proofer chamber, through the chamber panel openings, and both upward and downward over the heating element and back to the chamber along both the upper air flow path and the lower air flow path. Both a heat output by the heating element and a source of water are controlled to produce a temperature condition and humidity condition within the chamber suitable for proofing dough. In order to provide some air escape in such proofers the door has been mounted to provide a gap at the door threshold.

It would be advantageous to provide a dough proofer with an improved air flow arrangement and humidity control arrangement.

SUMMARY

In one aspect, a dough proofing apparatus includes a proofing chamber for holding dough during proofing operations and having a door for accessing the proofing chamber. An air duct assembly includes at least one inlet opening for drawing in air from the proofing chamber. At least one heating element is located within the air duct assembly for heating the air and a flow path for delivering the heated air back to the proofing chamber. A vent chamber is divided into an exhaust side and an intake side, the exhaust side fluidly connected to the air duct assembly, the intake side fluidly connected to the proofing chamber.

In another aspect, a dough proofing apparatus includes a chamber for holding dough during proofing operations and having a door for accessing the chamber. An air duct assembly is located at a first side of the chamber, the air duct assembly including first and second inlet openings along an upper or lower portion thereof. First and second fans are positioned in respective alignment with the first and second openings for drawing air from the chamber into the air duct assembly. A plurality of heating elements are located within a central heating duct of the air duct assembly and extend along the central heating duct. First and second outlet ducts extend vertically and are positioned at respective sides of the central heating duct. Each outlet duct including a respective flow passage in communication with the central heating duct. The first outlet duct includes a first plurality of outlet openings for directing heated air back into the chamber and the second outlet duct including a second plurality of outlet openings for directing heated air back into the chamber.

In a further aspect, a dough proofing apparatus includes a chamber for holding dough during proofing operations and having a door for accessing the chamber. An air duct assembly includes at least one inlet opening, a fan positioned for drawing air from the chamber through the inlet opening into the air duct assembly, and a heating arrangement within a central heating duct of the air duct assembly. The heating arrangement is positioned at an intermediate location along a depth of the central heating duct such that air flowing along the central heating duct to be heated passes on both a chamber facing side of the heating arrangement and a wall facing side of the heating arrangement.

DETAILED DESCRIPTION

Referring toFIGS. 1-3a dough proofing apparatus10is shown and includes a proofing chamber12defined in part by side walls14,16and18, along with door20that provides access to the chamber12for permitting a rack22of dough products to be moved into and out of the chamber12. A rack positioning guide rail25may be located within the chamber to aid in proper positioning of the rack22. Top wall or ceiling23of the chamber is also shown inFIG. 1. An air duct assembly24is located at side26of the chamber adjacent wall14. The air duct assembly24includes a chamber facing duct panel28including inlet openings30A and30B along an upper portion of the panel, where the inlet openings are spaced horizontally apart from each other. Fans32A and32B are positioned within the air duct assembly in respective alignment with the first and second openings30A and30B for drawing air from the chamber12into the air duct assembly. In one embodiment, each of the fans is located adjacent an internal side of the panel28and is a centrifugal fan, such as a backward curved centrifugal fan.

The air duct assembly includes a central heating duct34flanked by outlet ducts36A and36B. A heating arrangement38including a plurality of heating elements38A,38B and38C (e.g., resistive heating elements) is located within the central heating duct34of the air duct assembly and extends downwardly along the central heating duct from the fans32A and32B toward a lower end40of the central heating duct. Notably, the heating arrangement38may be mounted within the duct assembly frame54at an intermediate location along the depth of the frame that allows air to flow along both a chamber facing side of the heating arrangement and a wall facing side of the heating arrangement. The outlet ducts36A and36B extend vertically and are positioned at respective sides of the central heating duct34. Each outlet duct includes a respective flow passage42A and42B in communication with the central heating duct34. Outlet duct36A includes a plurality of outlet openings44A for directing heated air back into the chamber12and outlet duct36B includes a plurality of outlet openings44B for directing heated air back into the chamber12. In one embodiment, the outlet openings44A and44B may be formed as vertically extending, louvered elongated slots, with the louvers enabling the direction of air exiting the outlet ducts36A and36B to be adjusted.

Referring toFIGS. 1 and 2the general air flow of the proofer is described with reference to air flow indicating arrows46. During operation of the fans32A and32B, air flows into the air duct assembly24through the inlet openings30A and30B, where it is directed radially outward of the fans within the air duct assembly. The air then flows downward along the central heating duct34(e.g., along both the chamber facing side and wall facing side of the heating arrangement) to be heated by the plurality of heating elements, and then laterally into and upward along each of the outlet ducts36A and36B. The heated air also exits the outlets44A, generally along the full vertical height of the outlet duct36A, as a front or door side outlet flow which runs along the front or door side of the chamber12toward the right side48of the chamber12, opposite side26where the duct assembly24is located. The heated air exits the outlets44B, generally along the full vertical height of the outlet duct36B, as a back side outlet flow which runs along the back side of the chamber12toward the right side48of the chamber12. The front side flow moves rearward and the back side flow moves forward such that the two flows meet along the right side48of the chamber and collectively flow back toward the left side26and the duct assembly24through the rack zone within the chamber. The air then reenters the duct assembly via the openings30A and30B to be reheated and recirculated. As the air moves back from the right side48of the chamber toward the air duct assembly, the upper location of the fans32A and32B will cause the air to also move upwardly. As seen inFIG. 1, some air may also flow from a bottom opening of the central air duct34and laterally across the floor of the chamber to the right side48of the chamber, and then join with the front and rear side air flows.

As shown inFIG. 3, the duct assembly24may also include an internal water spraying and collection system. A water spray nozzle90may be selectively fed water (e.g., under control of a valve) from a water line to increase humidity within the chamber by evaporation of the water. A drain pan50and drain tee52are provided for collecting and draining any excess water.

Notably, the bottom of the door includes a sweep element56(FIG. 1) that makes a substantial seal at the door threshold so that air is prevented from flowing in and out of the chamber along this path.

Referring now toFIGS. 1 and 4, the top of the air duct assembly24includes a series of openings. Openings58are used to run wiring etc. such as heating element harnesses60, and may be closed or sealed after such wiring is run. Openings62are provided to facilitate a venting operation of the proofer in order to control humidity level within the proofer. In particular, openings62align with a top wall opening64so that air can flow (per arrows66) from within the air duct assembly through openings62and top wall opening64into one side of an exhaust vent chamber68(in this case formed as a vent box structure) that sits atop the top wall, at least when the vent chamber has been opened. Likewise, when the vent chamber is open ambient air can flow (per arrow70) into the chamber through the other side of vent chamber68and top wall opening69. The top wall opening69leads into the proofer chamber external of the air duct assembly24.

The vent chamber68is divided into the exhaust side72(aligned over toop wall opening64) and the intake side74(aligned over top wall opening69) by a dividing panel76. The dividing panel projects upward through a slot78in the top panel80of the vent chamber68as shown. The top panel80can be selectively pivoted (e.g., by motor drive82) between a lowered or closed, non-venting position that is illustrated inFIG. 4(in which the top panel80seals (e.g., via a gasket) to the top of the vent chamber walls to substantially prevent air egress and ingress) and a raised or open, venting position that is illustrated inFIG. 5(in which both sides of the vent chamber are open to permit air flow out of the exhaust side72and into the intake side74). Notably, the upward extension of the dividing panel76helps prevent or limit air that is being exhausted from the proofer on exhaust side72from short-circuiting and being immediately pulled back into the proofer through the intake side74.

The selective venting operation of the proofer may be carried out under control of a controller (e.g., see control box100atop the top wall) that is wired to control the various proofer components (e.g., heaters, fans, water valve, vent motor drive and one or more sensors). As used herein, the term controller is intended to broadly encompass any circuit (e.g., solid state, application specific integrated circuit (ASIC), an electronic circuit, a combinational logic circuit, a field programmable gate array (FPGA)), processor (e.g., shared, dedicated, or group—including hardware or software that executes code) or other component, or a combination of some or all of the above, that carries out the control functions of the proofer apparatus or the control functions of any component thereof. As seen inFIG. 1a control interface104is provided on the door20to enable an operator to initiate and stop proofer operations and/or adjust proofer settings. The control interface104may include programming or other logic to effect and control the control box100and together the interface104and control box100may make up the controller.

Apparatus control may be according to a set humidity level for a given proofing operation, with a temperature/humidity sensor102(FIG. 1) provided within the chamber to monitor humidity level.

By way of example, with the vent chamber68closed, the controller may initially control a proofing operation by energizing the heaters and fans, and delivering water to the spray nozzle90to bring the proofer temperature up and raise the humidity level. If the sensed humidity level exceeds a set level for the proofing operation, the controller operates to open the vent chamber68, causing moist air within the proofer to be exhausted and drier external ambient air to be drawn in, thereby lowering the humidity level within the proofer. When the humidity level again falls to an acceptable level, the controller operates to again close the vent chamber68to stop the air exchange. The proofer may also be used in a dehumidifying mode, where water is not added via the spray nozzle90at all. As moisture evaporates from the food product within the chamber and the humidity level rises above a set level, then the controller opens the vent chamber68to bring the humidity level back down to a desired level. In either case the controller will simultaneously use feedback from temperature/humidity sensor102to control the energization of the heating elements38A,38B and38C to maintain a desired temperature for the proofing or dehumidification operation.

Notably, the fan32B and vent chamber68arrangement facilitates the venting operation because the fan32B creates a high pressure zone immediately below the air duct assembly openings62so that when the vent chamber68is in the opened for venting, air will tend to flow out of the openings62up through opening64and out of side72of the vent chamber68. The outflow of air from the proofer creates a negative pressure condition within the proofer chamber12so that air will automatically be drawn into the proofer chamber12through side74of the vent chamber and opening69. Thus, the single action of opening the vent chamber while the air duct assembly fan32B is running causes both the exhausting of the proofer air and the intake of the external ambient air, without the need for use of any separate or dedicated exhaust blowers or fans. Also, the location of air being expelled from the duct assembly (i.e., upstream of the heating elements) means that the air is vented just before being heated (e.g., when it is the coolest) in order to reduce heat losses caused by the venting. The location of the ambient air entry opening69is external of the air duct assembly24but proximate the air duct assembly inlet opening30B such that the bulk of the entering ambient air will be pulled into the air duct assembly (along with proofing chamber air) and thus the ambient air quickly mixes with the more humid proofer chamber air and is circulated throughout the proofing chamber to lower the relative humidity throughout the proofing chamber.

It is to be clearly understood that the above description is intended by way of illustration and example only, is not intended to be taken by way of limitation, and that other changes and modifications are possible. For example, while the illustrated embodiment shows the fans located in an upper portion of the air duct assembly and air movement downward along the central heating duct, in other implementations the fans could be located in a lower portion of the air duct assembly with air movement upward along the central heating duct. The location of the air duct assembly could also vary. Likewise, the number of heating elements and fans could be varied.