TANK ASSEMBLY AND METHOD

• US 20120031084A1
• Filed: 08/06/2010
• Published: 02/09/2012
• Est. Priority Date: 08/06/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Perrin, James M.
• Granted Patent: US 8,875,495 B2
• Time in Patent Office: Days
• US Class Current: 60/299
• CPC Class Codes: B60K 15/061 with level control
• CPC Class Codes: G01F 23/246 thermal devices

Abstract

A tank assembly includes a tank defining a chamber that is configured to store a selectively variable volume of liquid. A positive temperature coefficient heater is disposed within the chamber. A source of electrical energy is in selective electrical communication with the heater and is configured to transfer electrical current to the heater. A controller is operatively connected to the heater and is configured to monitor the amount of electrical current to the heater. The controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater.

Claims

1. A tank assembly comprising:

a tank defining a chamber that is configured to store a selectively variable volume of liquid;

a positive temperature coefficient heater disposed within the chamber;

a source of electrical energy in selective electrical communication with the heater and configured to transfer electrical current to the heater; and

a controller operatively connected to the heater and configured to monitor the amount of electrical current to the heater;

wherein the controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater.

2. The tank assembly of claim 1, further comprising a temperature sensor operatively connected to the controller to transmit sensor signals thereto;

wherein the controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater and the sensor signals.

3. The tank assembly of claim 1, further comprising an output device;

and wherein the controller is programmed to transmit a sensor signal that is indicative of the volume of liquid in the chamber to the output device.

4. The tank assembly of claim 1, wherein the chamber is characterized by a minimum level of liquid and a maximum level of liquid;

and

wherein the heater extends from the minimum level to the maximum level.

5. An engine assembly comprising:

an engine that selectively produces exhaust gas;

a catalyst;

an exhaust conduit that provides fluid communication between the engine and the catalyst;

a tank defining a chamber that is configured to selectively store a variable volume of liquid that is in fluid communication with the exhaust conduit;

a positive temperature coefficient heater disposed within the chamber;

a source of electrical energy in selective electrical communication with the heater and configured to transfer electrical current to the heater; and

a controller operatively connected to the heater and configured to monitor the amount of electrical current to the heater;

wherein the controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater.

6. The tank assembly of claim 5, further comprising a temperature sensor operatively connected to the controller to transmit sensor signals thereto;

wherein the controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater and the sensor signals.

7. The tank assembly of claim 5, further comprising an output device;

and wherein the controller is programmed to transmit a sensor signal that is indicative of the volume of liquid in the chamber to the output device.

8. The tank assembly of claim 5, wherein the chamber is characterized by a minimum level of liquid and a maximum level of liquid;

and

wherein the heater extends from the minimum level to the maximum level.

9. A method comprising:

determining the amount of electrical current flowing to a positive thermal coefficient heater inside a tank; and

determining the amount of liquid inside the tank based on the amount of electrical current flowing to the heater; and

transmitting a signal indicative of the amount of liquid inside the tank to an output device.

10. The method of claim 9, further comprising measuring a temperature;

and

wherein determining the amount of liquid inside the tank based on the amount of electrical current flowing to the heater includes using the measured temperature.