AUTOMATIC ANTI-GLARE REARVIEW MIRROR SYSTEM

• US 3,601,614 A
• Filed: 05/25/1970
• Issued: 08/24/1971
• Est. Priority Date: 05/25/1970
• Status: Expired due to Term

• Current Assignee: George E. Platzer
• Original Assignee: George E. Platzer
• Inventors: Platzer, George E.
• Primary Examiner(s): Lawrence, James W.
• Assistant Examiner(s): Grigsby, T. N.
• Application Number:
  US05/040,446
• Time in Patent Office: 456 Days
• Field of Search: 250/208,209,210 307/311 317/127,130 350/279,289
• US Class Current: 250/214.0AL
• CPC Class Codes: B60R 1/087 with remote or automatic control means
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: B60R 1/089 using a liquid filtering layer of variable thickness

Abstract

Control circuit and system for changing an automotive rear view mirror between a day and a night reflective condition. The circuit includes a forwardly facing photocell for sensing ambient illumination and a rearwardly facing photocell for sensing the illumination on a mirror from the headlights of a following vehicle.

Claims

1. A control circuit for a mirror movable between a first and second position on an automotive vehicle comprising first means for sensing the forward ambient illumination as seen by the driver of the vehicle, second means for sensing illumination on the mirror from the headlights of another vehicle following the first mentioned vehicle, an amplifier including means electrically connecting said first and second means in circuit, an electrical power source connected to said amplifier, an initiating device adapted to initiate movement of the mirror from said first position to said second position upon receiving a signal from said amplifier, when the illumination sensed by said second means bears a predetermined relationship to the illumination sensed by said first means over a range of ambient illumination and following vehicle headlight illumination conditions, sending said signal to said initiating device.

2. A control circuit as set forth in claim 1 further including adjustable sensitivity means electrically connected to said amplifier and said first and second means for varying the predetermined relationship, between the illumination sensed by the second means and the illumination sensed by said first means, necessary to cause said amplifier to send said signal to said initiating device.

3. A control circuit as set forth in claim 1 further including means for delaying the termination of the signal to said initiating device for a predetermined period of time after the illumination on said first and second means is such that said signal should be terminated.

4. A control circuit as set forth in claim 3, further including adjustable sensitivity means electrically connected to said amplifier and said first and second means for varying the predetermined relationship, between the illumination sensed by the second means and the illumination sensed by said first means, necessary to cause said amplifier to send said signal to said initiating device.

5. A control circuit as set forth in claim 1 wherein said amplifier includes a plurality of transistors connected together to form a direct coupled amplifier.

6. A controlled circuit as set forth in claim 1 wherein said amplifier includes a field effect transistor.

7. A control circuit for a mirror movable between a day position and a night position on an automotive vehicle comprising a first photocell for sensing the forward ambient illumination as seen by the driver of the vehicle, a second photocell for sensing the illumination on the mirror from the headlights of another vehicle following the first mentioned vehicle, an amplifier including means connecting said first and second photocells in circuit, an electrical power source connecting to said amplifier, an initiating device adapted to initiate movement of the mirror from the day position to the night position upon receiving a signal from said amplifier, when the illumination on said second photocell bears a predetermined relationship to the illumination on said first photocell over a range of ambient illumination and following vehicle headlight illumination conditions, sending said signal to said initiating device.

8. A control apparatus for a mirror movable between first and second positions on an automotive vehicle in response to a signal comprising first and second control valves, a line connected between said first control valve and the intake manifold of the engine of the automotive vehicle, a second line connecting said first control valve to said second control valve, a pressure actuated device for controlling movement of the mirror between said positions, a third line connecting said second control valve to said pressure actuated device, a fourth line connecting said second control valve to atmospheric pressure, said second control valve including a control member movable between a first position in which said second and third lines are placed in communication with one another to cause said pressure actuated device to be placed in communication with the intake manifold and a second position wherein said third and fourth lines are placed in communication with one another to cause said pressure actuated device to be placed in communication with the atmosphere, said control member being adapted to move between its said first and second positions in response to said signal.

9. A control system for a mirror movable between a day position and a night position on an automotive vehicle comprising a control circuit including a first photocell for sensing the forward ambient illumination as seen by the driver of the vehicle, a second photocell for sensing the illumination on the mirror from the headlights of another vehicle following the first mentioned vehicle, an amplifier including means connecting said first and second photocells in circuit, an electrical power source connecting to said amplifier, an initiating device adapted to initiate movement of the mirror from the day position to the night position upon receiving a signal from said amplifier, when the illumination on said second photocell bears a predetermined relationship to the illumination on said first photocell, sending said signal to said initiating device, first and second control valves, a line connected between said first control valve and the intake manifold of the engine of the automotive vehicle, a second line connecting said first control valve to said second control valve, a pressure actuated device for controlling movement of the mirror between said positions, and a third line connecting said second control valve to said pressure actuated device, a fourth line connecting said second control valve to atmospheric pressure, said second control valve including a control member movable between a first position in which said second and third lines are placed in communication with one another to cause said pressure actuated device to be placed in communication with the intake manifold and a second position wherein said third and fourth lines are placed in communication with one another to cause said pressure actuated device to be placed in communication with the atmosphere, said control member being adapted to move between its said first and second positions in response to said signal.

10. A control circuit for a mirror changeable between first and secOnd reflective conditions on an automotive vehicle comprising first means for sensing the forward ambient illumination as seen by the driver of the vehicle, second means for sensing illumination on the mirror from the headlights of another vehicle following the first mentioned vehicle, an amplifier including means electrically connecting said first and second means in circuit, an electrical power source connected to said amplifier, an initiating means adapted to initiate a change in the reflectivity of the mirror away from said first condition toward said second condition upon receiving a signal from said amplifier, said amplifier, when the illumination sensed by said second means bears a predetermined relationship to the illumination sensed by said first means over a range of ambient illumination and following vehicle headlight illumination conditions, sending said signal to said initiating means.

11. A control circuit for a mirror changeable between a day and a night reflective condition on an automotive vehicle comprising first photocell means for sensing the forward ambient illumination as seen by the driver of the vehicle, second photocell means for sensing illumination on the mirror from the headlights of another vehicle following the first mentioned vehicle, an amplifier including means electrically connecting said first and second photocell means in circuit, an electrical power source connected to said amplifier, an initiating means adapted to initiate a change in the reflectivity of the mirror away from said day reflective condition toward said night reflective condition upon receiving a signal from said amplifier, said amplifier, when the illumination sensed by said second photocell means bears a predetermined relationship to the illumination sensed by said first photocell means over a range of ambient illumination and following vehicle headlight illumination conditions, sending said signal to said initiating means.