Heater core isolation valve position detection

• US 10,207,567 B2
• Filed: 03/07/2013
• Issued: 02/19/2019
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Porras, Angel Fernando
• Primary Examiner(s): Rojohn, III, Claire
• Application Number:
  US13/787,900
• Publication Number:
  US 20140110081A1
• Time in Patent Office: 2,175 Days
• Field of Search: 165202, 165 111, 165 43
• CPC Class Codes: B60H 1/004 for vehicles having a combustion engine and electric drive means, e.g. hybrid electric vehicles
• CPC Class Codes: B60H 1/00978 Control systems or circuits characterised by failure of detection or safety means; Diagnostic methods
• CPC Class Codes: B60H 1/034 from the cooling liquid of the propulsion plant and from an electric heating device
• CPC Class Codes: F01P 11/04 Arrangements of liquid pipes or hoses
• CPC Class Codes: F01P 2060/08 Cabin heater

Abstract

A vehicle is disclosed that has multiple coolant paths selected by control of a three-way valve in which the position of the valve is detectable. A method for detecting the valve position during fault conditions is disclosed. The vehicle has a heating system that includes a first coolant loop with a heating source, a water pump, and a heater core. The heating system also has a second coolant loop that includes an engine and a second water pump, in addition to the elements of the first coolant loop. Temperature sensors are located in each coolant loop. A three-way valve fault is detected by monitoring the behavior of the temperature sensors in response to the position of the three-way valve and the status of the heating sources.

Claims

1. A vehicle comprising:

a valve configured to selectively direct coolant from an engine to a coolant loop including a heat exchanger and an electric heater; and

a controller programmed to receive temperature data and, in response to commanding the valve to a position, identify the position based on a temperature of coolant entering the heat exchanger and a temperature of coolant exiting the engine.

2. The vehicle of claim 1 wherein the controller is further programmed to identify an isolated position in which the valve does not direct coolant from the engine to the coolant loop in response to a temperature increase of the coolant entering the heat exchanger being greater than a temperature increase of the coolant exiting the engine after commanding the valve to fluidly isolate the engine from the coolant loop while the electric heater is on and the engine is off.

3. The vehicle of claim 2 wherein the temperature increase of the coolant entering the heat exchanger is greater than a first threshold and the temperature increase of the coolant exiting the engine is less than a second threshold.

4. The vehicle of claim 1 wherein the controller is further programmed to identify a fault position in which the valve directs the coolant from the engine to the coolant loop in response to a temperature increase of the coolant entering the heat exchanger and a temperature increase of the coolant exiting the engine after commanding the valve to fluidly isolate the engine from the coolant loop while the electric heater is on and the engine is off.

5. The vehicle of claim 4 wherein controller is further programmed to identify the fault position in response to the temperature increase of the coolant entering the heat exchanger being less than a first threshold value or the temperature increase of the coolant exiting the engine being greater than a second threshold value.

6. The vehicle of claim 4 wherein the controller is further programmed to generate an output representing a fault in the position.

7. A vehicle comprising:

a valve configured to selectively direct coolant from an engine to a coolant loop including an electric heater and a heat exchanger; and

a controller programmed to receive temperature data and, in response to commanding the valve to a position, identify the position based on a change in temperature of coolant exiting the electric heater relative to a change in temperature of coolant exiting the engine.

8. The vehicle of claim 7 wherein the controller is further programmed to identify an isolated valve position in which the valve does not direct coolant from the engine to the coolant loop in response to a change in temperature of the coolant exiting the electric heater being greater than a change in temperature of the coolant exiting the engine after commanding the valve to fluidly isolate the engine from the coolant loop while the electric heater is on and the engine is off.

9. The vehicle of claim 8 wherein the change in temperature of the coolant exiting the electric heater is greater than a first threshold and the change in temperature of the coolant exiting the engine is less than a second threshold.

10. The vehicle of claim 7 wherein the controller is further programmed to identify a fault position in which the valve directs the coolant from the engine to the coolant loop in response to a change in temperature of the coolant exiting the electric heater and a change in temperature of the coolant exiting the engine after commanding the valve to fluidly isolate the engine from the coolant loop while the electric heater is on and the engine is off.

11. The vehicle of claim 10 wherein the fault position is identified in response to the change in temperature of the coolant exiting the electric heater being less than a first threshold value or the change in temperature of the coolant exiting the engine being greater than a second threshold value.

12. The vehicle of claim 10 wherein the controller is further programmed to generate an output representing a fault in the valve position.