Toaster with controlled conveyor speed

Patent metadata

Field	Value
Publication number	US-10004358-B2
Application number	US-201213473285-A
Country	US
Kind code	B2
Filing date	May 16, 2012
Priority date	May 16, 2012
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

A conveyor oven comprising a housing defining a cook chamber and a heating element adjacent the cook chamber. A controller is programmed to control a cook time based upon a current estimated temperature in the oven, wherein the current estimated temperature is a function of a heat power input during a previous time period and can also be a function of a previous estimated temperature. The oven can further include a conveyor and a motor coupled to the conveyor, wherein the controller is programmed to control a cook time of the conveyor. The controller can also be programmed to control the cook time based upon a product loading condition. The oven can further include a presence sensor for detecting the presence of food in the oven and for providing a corresponding signal. Preferably, the calculation is an eye calculation that is a function of a previous eye calculation.

First claim

What is claimed is:

1. An oven comprising:
a housing defining a cook chamber;
a heating element positioned adjacent the cook chamber;
a controller programmed, upon a change in a heat power setting of the heating element, to control a cook time based upon a current predicted cooking ability of the oven, wherein the current predicted cooking ability is calculated by the controller using a formula that is a function of a heat power input during a previous time period, a predicted cooking ability from a previous time period, and a heat time constant that represents the estimated rate at which a change in the heat power input causes a change in cooking ability.

2. An oven as claimed in claim 1 , wherein the predicted cooking ability from a previous time period is multiplied by the heat time constant.

3. An oven as claimed in claim 1 , wherein the current predicted cooking ability comprises a current estimate temperature that is calculated according to a formula comprising:
ET=(ET previous *HTC)+(HP previous *(1−HTC),

wherein ET=current estimated temperature,
ET previous =estimated temperature from a previous time period,
HTC=heat time constant, and
HP previous =heat percentage from a previous time period.

4. An oven as claimed in claim 3 , further comprising:
a conveyor positioned to move food product through the cook chamber; and
a motor coupled to the conveyor, wherein the controller is programmed to control a speed of the conveyor.

5. An oven as claimed in claim 4 , wherein the controller is programmed to control the speed of the conveyor based upon speed modification that is calculated according to a formula comprising:
MOD heat =1+((ET top −HS top )/HS top )+((ET bot −HS bot )/HS bot ),

wherein MOD heat =speed modification,
ET top =estimated temperature of the top element,
HS top =heat setting of the top element,
ET bot =estimated temperature of the bottom element, and
HS bot =heat setting of the bottom element.

6. An oven comprising:
a housing defining a cook chamber;
a heating element positioned adjacent the cook chamber;
a presence sensor positioned to sense the presence of food in the cook chamber; and
a controller programmed to control a cook time based upon a product loading condition determined by the controller, wherein the product loading condition is calculated by the controller using a formula that is a function of an amount of a product sensed by the presence sensor to be in the cook chamber over a period of time and a time constant that predicts how much cooking ability the amount of product placed in the cook chamber will remove from the cook camber.

7. An oven as claimed in claim 6 , wherein the presence of food in the oven is determined by a presence sensor.

8. An oven as claimed in claim 6 , wherein the calculation is an eye calculation that is a function of a previous eye calculation.

9. An oven as claimed in claim 8 , wherein the eye calculation is a function of the previous eye calculation and an eye time constant.

10. An oven as claimed in claim 9 , further comprising a product sensor providing an eye reading, wherein the eye calculation is calculated according to a formula comprising:
EC=(EC previous *ETC)+(Reading*(1−ETC))

wherein EC=eye calculation,
EC previous =previous eye calculation,
Reading=eye reading, and
ETC=eye time constant.

11. An oven as claimed in claim 6 , further comprising:
a conveyor positioned to move food product through the cook chamber; and
a motor coupled to the conveyor; wherein the controller is programmed to control a speed of the conveyor.

Assignees

• Wildebush Hans Anderson
• Hatco Corp

Inventors

• Wildebush Hans Anderson

Classifications

• A21B1/48

  with surfaces in the form of an endless band · CPC title

• F27B9/40

  Arrangements of controlling or monitoring devices · CPC title

• A47J37/044

  with conveyors moving in a horizontal or an inclined plane (A47J37/045, A47J37/046 take precedence) · CPC title

• A47J37/0623

  Small-size cooking ovens, i.e. defining an at least partially closed cooking cavity (A47J37/0605 takes precedence) · CPC title

• A47J37/0857 Primary

  with bread supports or heating means movable during the toasting operation · CPC title