# US 2014/0360382 A1 · Apparatus and method for controlling a conveyor oven > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0360382 A1 - Document ID: US20140360382A1 - Status: Published application - Kind: A1 - Application number: 14/469,192 - Filed: 2014-08-26 - Published: 2014-12-11 - Earliest claimed: 2009-08-28 - Assignees: The Middleby Corporation - Applicants: The Middleby Corporation - Inventors: William S. Schjerven, Sr.; John H. Wiker; Richard H. Van Camp; Theodore James Chmiola; Mark A. Sieron - Web page: https://patentgrep.com/patent/US20140360382A1 ## CPC - A47J 37/044: {with conveyors moving in a horizontal or an inclined plane (A47J37/045, A47J37/046 take precedence)} - A21B 1/245: {with a plurality of air nozzles to obtain an impingement effect on the food} - A47J 37/045: {with endless conveyors} - Y02P 60/80: Food processing, e.g. use of renewable energies or variable speed drives in handling, conveying or stacking - A47J: KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES - A21B: BAKERS' OVENS; MACHINES OR EQUIPMENT FOR BAKING (domestic baking equipment A47J37/00) - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A conveyor oven includes a controller configured to change the operation of a first set of burners and a second set of burners from a cooking mode to an energy saving mode based at least in part upon detection of the absence of food in the oven chamber. The first set of burners operating at a first intensity during the cooking mode and are off during the energy saving mode. The second set of burners operating at a first intensity during the cooking mode and being adjustable to a different intensity during the energy saving mode, where the second set of burners produce heat during the different intensity. ## Claims ### Claim 1 A conveyor oven comprising: an oven chamber in which food is cooked; a conveyor moveable to convey the food through the oven chamber; a gas burner to generate heat for the oven chamber, wherein the gas burner has a variable heat output and a combustion airflow rate; a main blower for circulating air within the oven chamber, wherein the main blower has variable speeds; a combustion blower that provides air to the gas burner, wherein the combustion blower has variable speeds; and a controller that controls the variable heat output and the combustion airflow rate of the gas burner, controls the speeds of the main blower and the combustion blower, and activates or increases the speed of the combustion blower when there is a decrease in the speed of the main blower and decreases the speed of the combustion blower or turns the combustion blower off when the speed of the main blower is sufficient to maintain a burner flame without assistance of the combustion blower. ### Claim 2 (depends on 1) The conveyor oven of claim 1, wherein the controller activates or increases the speed of the combustion blower when the speed of the main blower decreases to a threshold speed. ### Claim 3 (depends on 1) The conveyor oven of claim 1, wherein the controller reduces the speed of the main blower when the combustion airflow rate exceeds a predetermined minimum. ### Claim 4 (depends on 1) The conveyor oven of claim 1, further comprising a sensor to detect the absence of food in the oven chamber, wherein the controller, in response to the detection of the absence of food from the oven chamber, (i) reduces the speed of the main blower, (ii) activates or increases the speed of the combustion blower, and (iii) maintains the oven at a set-point temperature by varying the heat output of the gas burner. ### Claim 5 (depends on 4) The conveyor oven of claim 4, wherein the controller reduces the speed of the main blower and activates or increases the speed of the combustion blower after the passage of a predetermined period of time since food was last detected in the oven chamber. ### Claim 6 (depends on 4) The conveyor oven of claim 4, wherein the main blower operates at a first speed when food is present in the oven chamber, the main blower operates at a second speed slower than the first speed when the controller responds to the absence of the detection of food in the oven chamber, and the main blower operates at a third speed that is slower than the second speed when the combustion airflow rate exceeds a predetermined minimum. ### Claim 7 (depends on 4) The conveyor oven of claim 4, wherein the controller decreases the speed of the combustion blower or turns the combustion blower off when food is present in the oven chamber. ### Claim 8 (depends on 1) The conveyor oven of claim 1, wherein the controller reduces the speed of the main blower or turns the main blower off when the combustion blower is activated. ### Claim 9 A conveyor oven comprising: an oven chamber in which food is cooked; a conveyor moveable to convey the food through the oven chamber; a gas burner to generate heat for the oven chamber, wherein the gas burner has a variable heat output and a combustion airflow rate; a main blower for circulating air within the oven chamber, wherein the main blower has variable speeds and operates at a first speed when food is present in the oven chamber; a combustion blower that provides air to the gas burner, wherein the combustion blower has variable speeds; a sensor to detect at least one of a temperature within the oven and the presence of food product upon the conveyor; and a controller that controls the variable heat output and combustion airflow rate of the gas burner, and controls the speeds of the main blower and combustion blower, wherein the controller is responsive to the detection of the absence of food from the oven chamber based at least in part upon operation of the sensor and, in response to the detection of the absence of food from the oven chamber, the controller (i) reduces the speed of the main blower from the first speed to a second slower speed, (ii) activates or increases the speed of the combustion blower, and (iii) maintains the oven at a set-point temperature by varying the heat output of the gas burner, and (iv) increases the speed of the main blower from the second speed to the first speed in response to detecting the presence of food on the conveyor upstream from the oven chamber. ### Claim 10 (depends on 9) The conveyor oven of claim 9, wherein the controller reduces the speed of the main blower from the second speed to a third slower speed or turns the main blower off when the combustion blower is activated. ### Claim 11 (depends on 9) The conveyor oven of claim 9, wherein the controller decreases the speed of the combustion blower or turns the combustion blower off when food is present in the oven chamber. ### Claim 12 (depends on 9) The conveyor oven of claim 9, wherein the controller increases the speed of the main blower to the first speed in response to a signal received from the sensor. ### Claim 13 (depends on 9) The conveyor oven of claim 9, wherein the sensor detects a temperature in the oven. ### Claim 14 (depends on 13) The conveyor oven of claim 13, wherein the controller increases the speed of the main blower to the first speed in response to a signal received from the sensor. ### Claim 15 (depends on 9) The conveyor oven of claim 9, wherein the sensor detects both a temperature in the oven and the presence of food product on the conveyor. ### Claim 16 (depends on 9) The conveyor oven of claim 9, wherein the controller turns the main blower off when the combustion airflow rate exceeds a predetermined minimum. ### Claim 17 A conveyor oven comprising: an oven chamber in which food is cooked; a conveyor moveable to convey the food through the oven chamber; a gas burner to generate heat for the oven chamber, wherein the gas burner has a variable heat output and a combustion airflow rate; a main blower for circulating air within the oven chamber, wherein the main blower has variable speeds; a combustion blower that provides air to the gas burner, wherein the combustion blower has variable speeds; and a controller that controls the variable heat output and combustion airflow rate of the gas burner, controls the speed of the main blower, activates or increases the speed of the combustion blower when the main blower speed is reduced below a threshold, and reduces the speed of the main blower when the combustion blower is activated. ### Claim 18 (depends on 17) The conveyor oven of claim 17, wherein the controller turns the main blower off when the combustion airflow rate is at a second predetermined minimum. ### Claim 19 (depends on 17) The conveyor oven of claim 17, wherein the controller turns the combustion blower off when there is food present in the oven chamber. ### Claim 20 (depends on 17) The conveyor oven of claim 17, further comprising a sensor to detect the absence of food in the oven chamber, wherein the controller is responsive to the detection of the absence of food from the oven chamber by the sensor and, in response to the detection of the absence of food from the oven chamber, the controller (i) reduces the speed of the main blower, (ii) increases the speed of the combustion blower, and (iii) maintains the oven at a set-point temperature by varying the heat output of the gas burner. ### Claim 21 (depends on 20) The conveyor oven of claim 20, wherein the controller reduces the speed of the main blower and increases the speed of the combustion blower after the passage of a predetermined period of time since food was last detected in the oven chamber. ### Claim 22 (depends on 20) The conveyor oven of claim 20, wherein the main blower operates at a first speed when food is present in the oven chamber, the main blower operates at a second speed slower than the first speed when the controller responds to the absence of the detection of food in the oven chamber, and the main blower operates at a third slower speed or the main blower is turned off when the combustion blower is activated. ### Claim 23 A conveyor oven comprising: an oven chamber in which food is cooked; a conveyor moveable to convey the food through the oven chamber; a gas burner having a combustion airflow rate; a main blower for circulating air within the oven chamber, wherein the main blower has variable speeds; a damper for adjusting the gas burner combustion airflow rate, wherein the damper has variable configurations; and a controller that detects and changes the configuration of the damper for adjusting the gas burner combustion airflow rate. ### Claim 24 (depends on 23) The conveyor oven of claim 23, wherein the conveyor oven has a cooking mode and an energy saving mode and wherein the damper is in a first configuration during the cooking mode and is adjustable to a second different configuration in the energy saving mode. ### Claim 25 (depends on 23) The conveyor oven of claim 23, further comprising: a sensor to detect the absence of food in the oven chamber, wherein the controller is responsive to the detection of the absence of food from the oven chamber by the sensor and, in response to the detection of the absence of food from the oven chamber, the controller (i) reduces the speed of the main blower, (ii) changes the configuration of the damper to maintain a desired combustion air flow rate, and (iii) maintains the oven at a set-point temperature by varying the heat output of the gas burner. ### Claim 26 (depends on 25) The conveyor oven of claim 25, wherein the controller reduces the speed of the main blower and changes the configuration of the damper after the passage of a predetermined period of time since food was last detected in the oven chamber.