Power fold mirror control circuit and method

• US 20060186682A1
• Filed: 03/25/2004
• Published: 08/24/2006
• Est. Priority Date: 03/25/2003
• Status: Active Grant

• Current Assignee: Schefenacker Vision Systems USA Incorporated (The Sumi Motherson Group)
• Original Assignee: Schenacker Vision Sustems Australia Pty Limited
• Inventors: Kay, Donald
• Granted Patent: US 7,282,881 B2
• Time in Patent Office: Days
• US Class Current: 296/1.110
• CPC Class Codes: B60R 1/07 by electrically powered actuators
• CPC Class Codes: B60R 1/074 for retracting the mirror arrangements to a non-use position alongside the vehicle
• CPC Class Codes: H02H 5/042 using temperature dependent resistors
• CPC Class Codes: H02H 7/0816 concerning the starting sequence, e.g. limiting the number of starts per time unit, monitoring speed during starting

Abstract

A circuit and method of reducing the occurrence of overheating of a power fold vehicle mirror. The circuit controls the operation of the power fold mirror such that when a portion of the circuit reaches or exceeds a predetermined temperature threshold, the vehicle mirror is prevented from at least folding in. In practice, the vehicle mirror will be allowed to fold out even when the predetermined temperature threshold has been reached or exceeded, to allow the vehicle door to be opened and the car to be driven. The vehicle mirror may be allowed to be folded in when the temperature of the circuit falls to or below a second predetermined temperature threshold.

Claims

1. A control circuit for controlling the operation of a power fold vehicle mirror, the control circuit comprising:

a temperature sensor; and

a vehicle mirror actuation control;

wherein

upon the temperature sensor sensing that a temperature of at least a portion of the control circuit has reached or exceeded a predetermined temperature threshold, the vehicle mirror actuation control prevents the vehicle mirror from at least folding in.

2. A control circuit according to claim 1 wherein upon the temperature sensor sensing that the temperature of at least the portion of the control circuit has reached or exceeded the predetermined temperature threshold, the vehicle mirror actuation control still allows the vehicle mirror to fold out.

3. A control circuit according to claim 1 wherein the temperature sensor is a thermistor.

4. A control circuit according to claim 3 wherein the vehicle mirror actuation control prevents said vehicle mirror from folding in until said temperature has fallen to or below a second predetermined temperature threshold.

5. A method of controlling the operation of a power fold vehicle mirror, controlled by a control circuit, the method including preventing the vehicle mirror from at least folding in if a temperature of at least a portion of the control circuit reaches or exceeds a predetermined temperature threshold.

6. A method according to claim 5 wherein if at least a portion of the control circuit reaches or exceeds the predetermined temperature threshold, the vehicle mirror is still allowed to fold out.

7. A method according to claim 6 wherein the vehicle mirror is allowed to be folded in after the temperature falls to or below a second predetermined temperature threshold.