Steam Injection System and Method

Abstract

An oven steam injection system includes an oven having a compartment enclosed on all sides, a door on a front side of the compartment, the door operable to open the compartment, and a steam injector disposed inside the compartment. The oven steam injection system also includes a steam generator having a heater reservoir and a heating element that is operable to heat water within the heater reservoir to generate steam. The steam generator is operable to inject steam into the compartment through the steam injector.

What is claimed is: 
     
         1 . An oven steam injection system comprising:
 an oven comprising:
 a compartment enclosed on all sides; 
 a door on a front side of the compartment, the door operable to open the compartment; and 
 a steam injector disposed inside the compartment; and 
   a steam generator external to the compartment, comprising:
 a heater reservoir; and 
 a heating element operable to heat water within the heater reservoir to generate steam, 
 the steam generator operable to inject steam into the compartment through the steam injector. 
   
     
     
         2 . The oven steam injection system of  claim 1 , further comprising:
 a drain disposed at a bottom of the compartment, the drain operable to collect water from condensed steam at the bottom of the compartment; and   a drain pump operable to pump the water collected in the drain to the heater reservoir.   
     
     
         3 . The oven steam injection system of  claim 2 , further comprising:
 a drain reservoir;   a generator supply pump; and   a generator level sensor for detecting a level of water in the heater reservoir, wherein:
 the drain pump is operable to pump the water collected in the drain to the drain reservoir; and 
 the generator supply pump is operable to pump water from the drain reservoir to the heater reservoir when the level of water in the heater reservoir as detected by the generator level sensor is below a predetermined low heater reservoir threshold. 
   
     
     
         4 . The oven steam injection system of  claim 3 , further comprising:
 a water supply operatively connected to the drain reservoir; and   a drain reservoir level sensor for detecting a level of water in the drain reservoir,   wherein the water supply provides water to the drain reservoir when the level of water in the drain reservoir as detected by the drain reservoir level sensor is below a predetermined low drain reservoir threshold.   
     
     
         5 . The oven steam injection system of  claim 1 , further comprising:
 a drain reservoir disposed below the compartment, the drain reservoir operable to collect water by gravity from steam that has condensed in the compartment;   a generator supply pump; and   a generator level sensor for detecting a level of water in the heater reservoir,   wherein the generator supply pump is operable to pump water from the drain reservoir to the heater reservoir when the level of water in the heater reservoir as detected by the generator level sensor is below a predetermined low heater reservoir threshold.   
     
     
         6 . The oven steam injection system of  claim 5 , further comprising:
 a water supply operatively connected to the drain reservoir; and   a drain reservoir level sensor for detecting a level of water in the drain reservoir,   wherein the water supply provides water to the drain reservoir when the level of water in the drain reservoir as detected by the drain reservoir level sensor is below a predetermined low drain reservoir threshold.   
     
     
         7 . The oven steam injection system of  claim 1 , further comprising:
 compartment heating elements that are located on a side of the compartment.   
     
     
         8 . The oven steam injection system of  claim 7 , wherein the compartment heating elements are PTC elements. 
     
     
         9 . The oven steam injection system of  claim 1 , further comprising:
 a fan;   a motor that drives the fan; and   a baffle plate located in front of the fan;   wherein the fan, motor, and baffle plate are configured to evenly distribute the injected steam throughout the compartment.   
     
     
         10 . The oven steam injection system of  claim 9 , wherein the steam injector injects steam at a single point within the compartment. 
     
     
         11 . A method of injecting steam into an oven, the method comprising:
 providing water in a heater reservoir that is disposed outside of a compartment of the oven;   heating the water in the heater reservoir by a heating element to generate steam;   injecting steam from the heater reservoir into the compartment through a steam injector disposed in the compartment.   
     
     
         12 . The method of  claim 11 , further comprising:
 collecting water from condensed steam in a drain at a bottom of the compartment;   pumping the water collected in the drain to the heater reservoir.   
     
     
         13 . The method of  claim 12 , further comprising:
 detecting a level of water in the heater reservoir;   pumping the water collected in the drain to a drain reservoir by a drain pump; and then   pumping water from the drain reservoir to the heater reservoir by a generator supply pump when the level of water in the heater reservoir is below a predetermined low heater reservoir threshold.   
     
     
         14 . The method of  claim 13 , further comprising:
 detecting a level of water in the drain reservoir; and   supplying water to the drain reservoir by a water supply when the level of water in the drain reservoir is below a predetermined low drain reservoir threshold.   
     
     
         15 . The method of  claim 11 , further comprising:
 collecting water in a drain reservoir disposed below the compartment, the water being collected in the drain reservoir by gravity from steam that has condensed in the compartment;   detecting a level of water in the heater reservoir; and   pumping water from the drain reservoir to the heater reservoir by a generator supply pump when the level of water in the heater reservoir is below a predetermined low heater reservoir threshold.   
     
     
         16 . The method of  claim 15 , further comprising:
 detecting a level of water in the drain reservoir; and   supplying water to the drain reservoir by a water supply when the level of water in the drain reservoir is below a predetermined low drain reservoir threshold.   
     
     
         17 . An steam oven system comprising:
 an oven comprising:
 a compartment enclosed on all sides; 
 a door on a front side of the compartment, the door operable to open the compartment; and 
 a water input disposed inside the compartment; and 
   a heating element external to the compartment; and   a water supply valve that controls an amount of water entering the compartment at the water input;   
       wherein:
 water that enters the compartment via the water input and that contacts a surface of the compartment is heated by the heating element to generate steam within the compartment. 
 
     
     
         18 . The steam oven of  claim 17 , further comprising:
 a fan;   a motor that drives the fan; and   a baffle plate located in front of the fan;   wherein the fan, motor, and baffle plate are configured to evenly distribute the injected steam throughout the compartment.   
     
     
         19 . The steam oven of  claim 17 , further comprising a flow control element that introduces water at a predetermined rate while the heating elements are operating. 
     
     
         20 . The steam oven of  claim 17 , further comprising a flow control element that introduces a predetermined volume of water prior to operating the heating elements. 
     
     
         21 . The steam oven of  claim 17 , further comprising:
 a pressure sensor; and   a controller that maintains a minimal pressure difference between the compartment and ambient pressure by manipulating energy provided to the heating elements.   
     
     
         22 . The steam oven of  claim 21 , further comprising:
 an air vent through which steam and water can be vented to address a pressure buildup.   
     
     
         23 . The steam oven of  claim 21 , further comprising:
 a temperature sensor; and   a controller that maintains a predefined temperature by manipulating energy provided to the heating elements.