Self-cleaning rotisserie oven

• US 8,375,848 B2
• Filed: 11/26/2008
• Issued: 02/19/2013
• Est. Priority Date: 01/15/2008
• Status: Active Grant

• Current Assignee: Premark FEG LLC (Illinois Tool Works Inc.)
• Original Assignee: Premark FEG LLC (Illinois Tool Works Inc.)
• Inventors: Valentine, Richard D., Mills, Nigel G., Weber, Matthew A., Heiser, James M., Blackmore, Clifford A.
• Primary Examiner(s): Kim, Gene
• Assistant Examiner(s): CHAMBERS, MICHAEL S
• Application Number:
  US12/323,909
• Publication Number:
  US 20090178576A1
• Time in Patent Office: 1,546 Days
• Field of Search: 994/21.HH, 994/21.H, 994/19, 994/21.R, 126/21.A, 126/19.R, 126/1.R, 219/400, 134/24, 134/172, 134/111, 134/58.DL
• US Class Current: 99/421.H
• CPC Class Codes: A47J 37/042 with food supports arranged on wheels or spiders rotating about a horizontal axis
• CPC Class Codes: F24C 14/005 using a cleaning liquid

Abstract

A self-cleaning rotisserie oven includes a cooking chamber for cooking food product. A rotor is used for supporting and moving a food product in the cooking chamber. A sump is positioned below the cooking chamber that collects water provided to the cooking chamber. A sensor is positioned to detect when the sump is filled to a set level. An inlet valve is configured to control supply of water to the cooking chamber. A controller is configured to carry out a self-cleaning process. The self-cleaning process includes (a) a pre-rinse phase where the controller (i) opens the inlet valve, (ii) closes the inlet valve when the sensor detects that the sump is filled to the set level, and (iii) determines a duration of time that the inlet valve was open during (i), and (b) a later phase during which the controller opens the inlet valve for an amount of time based on the duration of time determined during (a)(iii).

Claims

1. A self-cleaning rotisserie oven, comprising:

a cooking chamber for cooking food product;

a rotor for use in supporting and moving a food product in the cooking chamber;

a sump positioned below the cooking chamber that collects water provided to the cooking chamber;

a sensor positioned to detect when the sump is filled to a set level;

an inlet valve configured to control supply of water to the cooking chamber; and

a controller configured to carry out a self-cleaning process, the self-cleaning process including;

(a) a pre-rinse phase in which (i) the controller opens the inlet valve, (ii) the controller closes the inlet valve when the sensor detects that the sump is filled to the set level, and (iii) the controller determines a duration of time between opening of the inlet valve in step (a)(i) and closing of the inlet valve in step (a)(ii), and

(b) a later phase during which the controller opens the inlet valve for an amount of time that is determined and set by the controller as a function of the duration of time determined by the controller during step (a)(iii), the later phase occurring after the sump has been drained of water delivered in step (a).

2. The self-cleaning rotisserie oven of claim 1 further comprising a recirculating pump and a spray arm located in the cooking chamber, the controller configured to operate the recirculating pump during the later phase to provide water to the spray arm.

3. The self-cleaning rotisserie oven of claim 2, wherein the controller is configured to operate such that water used to fill the sump during step (a) is drained from the sump through a drain line and is not recirculated.

4. The self-cleaning rotisserie oven of claim 2 further comprising a chemical source and a chemical pump, wherein the controller is configured such that during the self-cleaning process the controller operates the chemical pump to add detergent to the sump from the chemical source while the sump is filling with water during step (b), and operates the recirculating pump to recirculate the water with detergent so added.

5. The self-cleaning rotisserie oven of claim 1, wherein the controller is configured such that during the self-cleaning process the controller:

prior to the pre-rinse phase, opens the inlet valve for an initial phase wherein the sump is filled with water, the water from the initial phase not being recirculated in any subsequent phase;

after the pre-rinse phase, opens the inlet valve for a wash phase where the sump is filled, the water from the wash phase including detergent; and

after the wash phase, opens the inlet valve for a post-rinse phase where the sump is filled; and

wherein one of the wash phase or the post-rinse phase is the later phase.

6. The self-cleaning rotisserie oven of claim 5, wherein both the wash phase and the post-rinse phase of the self-cleaning process carried out by the controller include opening the inlet valve for a duration of time dependent on the duration determined in step (a)(iii).

7. The self-cleaning rotisserie oven of claim 1 further including a rotating spray arm located within the cooking chamber above the sump, wherein water is provided to the cooking chamber through the spray action of the rotating arm in order to fill the sump when the inlet valve is open.

8. The self-cleaning rotisserie oven of claim 1, wherein the sensor is an electronic water level sensor.

9. The self-cleaning rotisserie oven of claim 1, wherein the amount of time that the inlet valve is open during step (b) is the same as the duration determined in step (a)(iii).

10. The self-cleaning rotisserie oven of claim 1, wherein during step (b) the controller closes the inlet valve during the later phase once it is true that

the sensor indicates that the sump is full, and that

the amount of time since opening the valve is at least the duration determined in step (a)(iii).

11. A self-cleaning oven, comprising:

a cooking chamber for cooking food product;

a sump positioned below the cooking chamber that collects water provided to the cooking chamber;

a sensor positioned to detect when the sump is filled to a set fill level;

an inlet valve configured to control supply of water to the cooking chamber; and

a controller connected to control the inlet valve and configured to establish a sump fill time for a self-cleaning operation as follows;

(a) the controller (i) opens the inlet valve, (ii) closes the inlet valve when the sensor indicates that the sump is filled to the set fill level, (iii) determines a duration of time between opening of the inlet valve in step (a)(i) and closing of the inlet valve in step (a)(ii) and (iv) determines the sump fill time as a function of the duration of time determined in step (a)(iii) such that variance in the duration of time determined in step (a)(iii) results in variance in the sump fill time, and

(b) during a phase of the self-cleaning operation the controller opens the inlet valve for the sump fill time regardless of an earlier indication by the sensor that the sump is filled to the set level, the phase occurring after the sump has been drained of water delivered in steps (a)(i) and (a)(ii).

12. A method for electronically controlling a self-cleaning oven operation, the method comprising:

(1) utilizing an oven including a cooking chamber, a sump positioned below the cooking chamber and a sump fill control system including a water source and a spray arm located above the sump to carry out the steps of

(a) filling the sump by delivering water from the water source to the spray arm, the spray arm spraying the cooking chamber with water until the sump is filled to a set level;

(b) determining an amount of time for filling the sump to the set level in step (a) and defining a sump fill time as a function of the determined amount of time such that variance in the determined amount of time will result in variance in the defined sump fill time; and

(c) filling the sump by delivering water from the water source to the spray arm for the sump fill time determined in step (b) after the sump has been drained.

13. The method of claim 12 further comprising delivering water from the sump to the spray arm using a recirculating pump after the sump is filled in step (c).

14. The method of claim 13 further comprising preventing water from being delivered from the water source to the spray arm by closing an inlet valve while water is being delivered from the sump to the spray arm using the recirculating pump.

15. The method of claim 12 comprising knocking down foam by filling the sump with water delivered from above the sump.

16. A method of carrying out a self-cleaning operation in an oven that includes a cooking chamber for cooking food product, a sump positioned below the cooking chamber that collects water provided to the cooking chamber, a sensor positioned to detect when the sump is filled to a set fill level, an inlet valve configured to control supply of water to the cooking chamber, and a controller connected to control the inlet valve, the method involving the controller establishing a sump fill time for the self-cleaning operation as follows:

(a) the controller (i) opens the inlet valve, (ii) closes the inlet valve when the sensor indicates that the sump is filled to the set fill level, (iii) determines a duration of time between opening of the inlet valve in step (a)(i) and closing of the inlet valve in step (a)(ii) and (iv) determines the sump fill time as a function of the duration of time determined in step (a)(iii) such that variance in the duration of time determined in step (a)(iii) results in variance in the sump fill time, and

(b) during a phase of the self-cleaning operation the controller opens the inlet valve for the sump fill time regardless of an earlier indication by the sensor that the sump is filled to the set level, the phase occurring after the sump has been drained of water delivered in steps (a)(i) and (a)(ii).