US 12,262,718 B2
Power modulator for infrared conveyor oven
William S. Schjerven, Sr., Schaumburg, IL (US); James Jeffery Hanson, Elgin, IL (US); and Ricky Joe Sullivan McIntosh, Altoona, IA (US)
Assigned to THE MIDDLEBY CORPORATION, Elgin, IL (US)
Filed by THE MIDDLEBY CORPORATION, Elgin, IL (US)
Filed on Aug. 25, 2023, as Appl. No. 18/455,991.
Application 18/455,991 is a continuation of application No. 17/190,244, filed on Mar. 2, 2021, granted, now 11,771,096.
Application 17/190,244 is a continuation of application No. 14/710,841, filed on May 13, 2015, abandoned.
Prior Publication US 2023/0404085 A1, Dec. 21, 2023
Int. Cl. A21B 1/40 (2006.01); A21B 1/22 (2006.01); A21B 1/48 (2006.01); H05B 1/02 (2006.01)
CPC A21B 1/40 (2013.01) [A21B 1/22 (2013.01); A21B 1/48 (2013.01); H05B 1/0263 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A conveyor oven comprising:
an oven compartment;
a conveyor extending through the oven compartment;
a motor that drives the conveyor;
a first heating element,
a first relay that controls a current flow to the first heating element;
a second heating element,
a second relay that controls a current flow to the second heating element;
a third heating element,
a third relay that controls a current flow to the third heating element;
a power supply that receives external power and distributes power to the first heating element, the second heating element, and the third heating element; and
an electronic controller electrically coupled to the power supply and to the first relay, the second relay, and the third relay, the electronic controller configured to:
execute a set of predetermined operations when a measured temperature in the oven compartment is less than a user adjustable temperature setpoint,
repeat the set of predetermined operations until the electronic controller receives a signal indicating that the measured temperature is equal to or greater than the user adjustable temperature setpoint, and
cease the set of predetermined operations upon receipt by the electronic controller of the signal indicating that the measured temperature is equal to or greater than the user adjustable temperature setpoint;
wherein the set of predetermined operations includes:
actuating the second relay and the third relay to energize the second heating element and the third heating element for a first predetermined period of time while the first heating element is de-energized during the first predetermined period of time,
actuating the second rely after the first predetermined period of time to de-energize the second heating element,
actuating the first relay after a second predetermined period of time to energize the first heating element,
actuating the third rely after a third predetermined period of time to de-energize the third heating element,
actuating the second relay after a fourth predetermined period of time to energize the second heating element,
actuating the first rely after a fifth predetermined period of time to de-energize the first heating element, and
actuating the third relay after a sixth predetermined period of time to energize the third heating element;
wherein the first predetermined period of time, the third predetermined period of time, and the fifth predetermined period of time are equal to one another and each are longer than the second predetermined period of time, the fourth predetermined period of time, and the sixth predetermined period of time, respectively, such that no more than three heating elements are energized simultaneously at any given time.