Electric pressure canner with digital control

Patent metadata

Field	Value
Publication number	US-10849342-B2
Application number	US-201816160459-A
Country	US
Kind code	B2
Filing date	Oct 15, 2018
Priority date	Oct 13, 2017
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

A digital pressure canner and related methods of operation that provide for improved safety and consistency during a food canning process by reducing temperature over and undershoot. The digital pressure canner includes a digital control operating with inputs from digital sensors to accurately control the canning temperature during the canning process. By reducing over and undershoot of canning temperatures, foods within the pressure canner are maintained at temperatures sufficient to kill any bacteria or microorganisms for the entire canning cycle. In order to verify operation of the digital canner at sufficient canning temperatures, mechanical safety devices, for example, a pressure relief valve can be utilized in conjunction with digital controllers and sensors to provide audible and visual feedback to a user during the canning process.

First claim

The invention claimed is:

1. A digital pressure canner, comprising: a vessel body;
a lid assembly mechanically coupled to the vessel body so as to define a pressurized canning area; and
a control circuit including a digital sensor probe and a digital controller operably connected to a heater assembly, wherein the digital sensor probe extends through the lid assembly such that the sensor probe is exposed to the pressurized canning area to measure a real-time internal canning temperature, the digital sensor probe communicating the real-time internal canning temperature to the digital controller, which subsequently varies a power output to the heater assembly, the digital sensor probe being mounted in a rotatable sensor mount that is rotatably connected to the vessel body.

2. The digital pressure of claim 1 , wherein the lid assembly further comprises a sensor channel defining a sensor bore and wherein the rotatable sensor mount is rotatably mounted such that rotation of the rotatable sensor mount directs the digital sensor probe through the sensor bore.

3. The digital pressure canner of claim 2 , wherein the rotatable sensor mount further comprises a sealing member for sealably engaging the sensor bore when the digital sensor probe is directed through the sensor bore.

4. The digital pressure canner of claim 3 , wherein the rotatable sensor mount further comprises a latch member, said latch member physically engaging a pair of projections on the sensor channel to secure the rotatable sensor mount relative to the sensor channel when the digital sensor probe is directed through the sensor bore.

5. The digital pressure canner of claim 4 , wherein the sensor channel includes a locking pin that is elevated above the sensor channel when the pressurized canning area is pressurized such that the latch member cannot be disengaged from the pair of projection when the pressurized canning area is pressurized.

6. The digital pressure canner of claim 1 , wherein the lid assembly further comprises a relief bore, said relief bore in communication with the pressurized canning area and wherein a pressure relief valve is mounted within the relief bore.

7. A method of canning food with a digital pressure canner, comprising:
mounting a digital sensor probe in a rotatable sensor mount that is rotatably connected to a vessel body of a pressurized canning vessel;
rotating the rotatable sensor mount relative to the vessel body such that the digital sensor probe is directed through a lid assembly of the pressurized canning vessel via a sensor bore defined in the lid assembly;
monitoring a real-time canning temperature within a pressurized canning area of the pressurized canning vessel using the digital sensor probe exposed to the pressurized canning area;
communicating the real-time canning temperature to a digital controller operably connected to the digital sensor probe; and
varying an output power supplied by the digital controller to a heater assembly on the pressurized canning vessel such that the real-time canning temperature is maintained at a desired canning temperature.

8. The method of claim 7 , wherein the rotatable sensor mount further comprises a sensor sealing member and wherein rotating the rotatable sensor mount further comprises:
sealing the digital sensor probe in the pressurized canning area by sealably engaging the sensor sealing member and the sensor bore.

9. The method of claim 8 , wherein the rotatable sensor mount further comprises a latching member and wherein sealing the digital sensor probe in the pressurized canning area further comprises:
engaging the latching member with a pair of engagement tabs on the lid assembly.

10. The method of claim 9 , wherein a locking pin is exposed to the pressurized canning area and further comprising:
lifting the locking pin when the pressurized canning area is under pressure, whereby the elevated locking pin prevents disengagement of the latching member from the pair of engagement tabs.

11. The method of claim 7 , wherein varying the output power supplied by the digital controller to the heater assembly further comprises:
controlling the output power such overshoot of the desired canning temperature by the real-time canning temperature is reduced.

12. The method of claim 7 , wherein varying the output power supplied by the digital controller to the heater assembly further comprises:
controlling the output power such that undershoot of the desired canning temperature by the real-time canning temperature is reduced.

13. The method of claim 7 , wherein varying the output power supplied by the digital controller to the heater assembly further comprises:
controlling the output power such overshoot of the desired canning temperature by the real-time canning temperature is reduced; and
controlling the output power such that undershoot of the desired canning temperature by the real-time canning temperature is reduced.

14. The method of claim 7 , further comprising:
mounting a pressure relief valve in a relief bore in the pressurized canning vessel such that the pressure relief valve is in communication with the pressurized canning area of the pressurized canning vessel; and
relieving excess pressure in the pressurized canning vessel with the pressure relief valve, said excess pressure being pressure higher than a pressure setting of the pressure relief valve.

15. The method of claim 14 , wherein controlling the output power supplied by the digital controller reduces the excess pressure in the pressurized canning vessel such that undershoot of the desired canning temperature the real-time canning temperature is reduced.

Assignees

• Nat Presto Industries Inc

Inventors

• Hedrington James A
• Warwick Julian

Classifications

• A23B2/103 Primary

  using sub- or super-atmospheric pressures, or pressure variations transmitted by a liquid or gas · CPC title

• A23B2/10

  by treatment with pressure variation, shock, acceleration or shear stress · CPC title

• A23B2/003

  Control or safety devices for sterilisation or pasteurisation systems · CPC title

• A23B2/30 Primary

  by heating materials in packages which are not progressively transported through the apparatus · CPC title

• G01D21/02

  Measuring two or more variables by means not covered by a single other subclass · CPC title