PHOTOELECTRICALLY-CONTROLLED REAR-VIEW MIRROW
First Claim
1. A rear view mirror for a vehicle wherein a reflective panel is selectively movable between two stable positions relative to said vehicle for providing a relatively bright reflected image in a first position and relatively weak reflected image in a second position, said mirror including:
- electromagnet means, including a single core, a current winding about said core and at least one permanent magnet armature, and responsive to current flow in one direction through said winding for magnetically retaining said armature at one location and responsive to current flow through said winding in a second direction for maintaining said armature at a second location;
linkage means responsive to said armature in said first location for moving and mechanically detenting said reflective panel to said first position and responsive to said armature in said second location for moving and mechanically detenting said reflective panel to said second position;
photo-sensitive means for sensing the intensity of light impinging upon said reflective panel;
electrical circuit means for providing current through said windinG in said one direction in response to intensities sensed by said photo-sensitive means below a predetermined intensity, and for providing current through said winding in said second direction in response to intensities sensed by said photosensitive means above said predetermined intensity.
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Accused Products
Abstract
A photoelectrically controlled rear-view mirror employs a first photocell to switch the mirror between '"'"''"'"''"'"''"'"'normal'"'"''"'"''"'"''"'"' and '"'"''"'"''"'"''"'"'adjusted'"'"''"'"''"'"''"'"' positions in response to incident light on the mirror, and a second photocell to monitor ambient light and prevent switching of the mirror to the '"'"''"'"''"'"''"'"'adjusted'"'"''"'"''"'"''"'"' position during daylight hours and at night where high ambient light conditions exist. Mirror switching is effected by a single electromagnet having a winding which conducts current in one direction or the other in accordance with the resistive states of the photocells. The electromagnet displaces an actuating cam to either of two stable positions in which the mirror is positioned in an adjusted or a normal position, respectively.
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Citations
25 Claims
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1. A rear view mirror for a vehicle wherein a reflective panel is selectively movable between two stable positions relative to said vehicle for providing a relatively bright reflected image in a first position and relatively weak reflected image in a second position, said mirror including:
- electromagnet means, including a single core, a current winding about said core and at least one permanent magnet armature, and responsive to current flow in one direction through said winding for magnetically retaining said armature at one location and responsive to current flow through said winding in a second direction for maintaining said armature at a second location;
linkage means responsive to said armature in said first location for moving and mechanically detenting said reflective panel to said first position and responsive to said armature in said second location for moving and mechanically detenting said reflective panel to said second position;
photo-sensitive means for sensing the intensity of light impinging upon said reflective panel;
electrical circuit means for providing current through said windinG in said one direction in response to intensities sensed by said photo-sensitive means below a predetermined intensity, and for providing current through said winding in said second direction in response to intensities sensed by said photosensitive means above said predetermined intensity.
- electromagnet means, including a single core, a current winding about said core and at least one permanent magnet armature, and responsive to current flow in one direction through said winding for magnetically retaining said armature at one location and responsive to current flow through said winding in a second direction for maintaining said armature at a second location;
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2. The Combination according to claim 1 further comprising:
- additional photo-sensitive means for sensing the intensity of ambient light; and
means responsive to light intensities above a further predetermined intensity sensed by said additional photo-sensitive means for maintaining current flow through said winding in said one direction.
- additional photo-sensitive means for sensing the intensity of ambient light; and
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3. The combination according to claim 2 further comprising adjustable means for varying said further predetermined intensity.
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4. The combination according to claim 2 wherein said additional photo-sensitive means comprises a photocell mounted to sense the ambient light intensity to the adjacent curb side of the motor vehicle operator.
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5. The combination according to claim 2 wherein said electrical circuit means comprises:
- a source of DC voltage;
a first current path including the collector-emitter circuits of a first pair of opposite-type transistors connected to opposite ends of said winding and in series between said source of DC voltage and ground;
a second current path including the collector-emitter circuits of a second pair of opposite type transistors connected to opposite ends of said winding and in series between said source of DC voltage and ground, said first and second current paths being arranged to conduct current through said winding in opposite directions; and
control means responsive to intensities sensed by said photo-sensitive means below said predetermined intensity for rendering said first pair of transistors conductive and said second pair of transistors non-conductive, and responsive to intensities sensed by said photo-sensitive means above said predetermined intensity for rendering said second pair of transistors conductive and said first pair of transistors non-conductive.
- a source of DC voltage;
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6. The combination according to claim 5 wherein said control means includes transient suppression means to prevent relatively short variations of intensities sensed by said photo-sensitive means from changing the conductivity states of said first and second pairs of transistors.
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7. The combination according to claim 2 wherein said electrical circuit means comprises:
- a source of DC voltage;
first and second silicon controlled rectifiers having anode, cathode and gate electrodes;
means for connecting opposite ends of said winding to respective ones of said anode electrodes;
a charging capacitor connected in parallel with said winding;
first and second anode resistors;
means for connecting the cathodes of said silicon controlled rectifiers to ground;
means for connecting the anodes of said first and second silicon controlled rectifiers in series with said first and second anode resistors, respectively, and said source of DC voltage;
means responsive to intensities sensed by said photo-sensitive means below said predetermined intensity for rendering said first silicon controlled rectifier conductive and said second silicon controlled rectifier non-conductive, and responsive to intensities sensed by said photo-sensitive means above said predetermined intensity for rendering said second silicon controlled rectifier conductive and said first silicon controlled rectifier non-conductive.
- a source of DC voltage;
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8. The combination according to claim 2 wherein said armature comprises:
- said at least one and a second permanent magnet disposed for translation between first and second locations in accordance with the direction of current through said winding, said at least one and said second permanent magnets being disposed at opposite ends of said single core with like poles facing one another; and
means for mechanically linking said magnets to one another to prevent mutual displacement thereof.
- said at least one and a second permanent magnet disposed for translation between first and second locations in accordance with the direction of current through said winding, said at least one and said second permanent magnets being disposed at opposite ends of said single core with like poles facing one another; and
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9. The combination according to claim 2 wherein said mirror includes a housing, means for securing said reflective panel and said core to said housing to prevent their movement relative to said housing, and a plate mounted interiorly of said housing for pivotal movement relative to said housing In a direction generally perpendicular to said reflective panel;
- and further comprising means for securing said plate to said vehicle; and
wherein said linkage means comprises a projection extending from said plate and a slotted cam extending from and movable with said armature, the slot of said cam being configured to engage and mechanically detent said projection in first and second positions relative to said housing when said armature is in said first and second locations respectively.
- and further comprising means for securing said plate to said vehicle; and
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10. The combination according to claim 9 wherein said projection is of generally rectangular cross-section, wherein the slot of said cam member extends in the plane of motion of said cam, said plane being perpendicular to said projection, and wherein said slot includes:
- A first section of generally rectangular cross-section arranged to engage said projection when said armature is in said first location;
a second section of generally rectangular cross-section arranged to engage said projection when said armature is in said second location, said first and second sections being disposed at opposite ends of said slot and at different distances from said mirror panel; and
a third section interconnecting said first and second sections, inclined relative to said mirror panel, and arranged for guiding said projection between said first and second sections during translation of said armature between said first and second locations.
- A first section of generally rectangular cross-section arranged to engage said projection when said armature is in said first location;
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11. In combination, a mirror, a camming device having a translatable cam and a cam follower, a pivot secured to said mirror about which said mirror oscillates angularly between two limiting positions, means linking said cam follower to said mirror so that said mirror oscillates angularly between said two limiting positions as said cam translates between two limiting positions and said cam follower correspondingly moves between two limiting positions, a reversible solenoidal motor connected to drive said translatable cam between its two limiting positions, a photoelectrically controlled bistable flip-flop circuit control system, including an ambient light sensing photo-resistor and a directionally sensitive light sensing photo-resistor, and means responsive to said control system for energizing said motor to actuate said cam to move between its two limiting positions in response to only high intensity light impacting on said last mentioned photo-resistor while low intensities of ambient light are sensed by both said photo-resistors.
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12. The combination according to claim 11, wherein said camming device includes mechanical latching means for mechanically latching said cam follower in its limiting positions.
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13. The combination according to claim 11, wherein said camming device includes permanent magnet latchinG means for magnetically latching said follower in its limiting positions.
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14. The combination according to claim 11, wherein said camming device includes mechanical latching means for mechanically latching said cam follower in its limiting positions, and wherein said camming device further includes permanent magnet latching means for magnetically latching said follower in its limiting positions.
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15. In combination, a mirror facing rearwardly of a vehicle, a camming device having a translatable cam and a cam follower movable transversely of the direction of translation of said translatable cam, a pivot, said mirror being secured in pivotable relation to said pivot, means securing said cam follower directly to said mirror so as to move said mirror angularly about said pivot between limiting positions in response to translation of said cam and corresponding transverse movement of said cam follower between limiting positions, bistable photoelectrically controlled motor means connected to drive said cam in alternative senses towards its limiting positions in response to a function of ambient light conditionS and the presence or absence of light arriving adjacent said mirror from only rearwardly of said vehicle.
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16. The combiNation according to claim 15, wherein said camming device includes mechanical latching means for retaining said cam follower in each of its limiting positions.
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17. The combination according to claim 15, wherein said camming device includes permanent magnet latching means for retaining said translatable cam in each of its limiting positions.
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18. The combination according to claim 15, wherein said camming device includes mechanical and also permanent magnet latching means for retaining said cam follower in its limiting positions and for retaining said cam in its limiting positions.
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19. The combination according to claim 15, wherein said bistable photoelectrically controlled motor means includes a solenoidal motor having a translatable armature coupled directly to said cam, and wherein said solenoidal motor further includes winding means arranged to drive said armature selectively in said alternative senses.
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20. The combination according to claim 15, wherein said bistable photoelectrically controlled motor means includes two photo-resistors, a first of said photo-resistors looking sidewise of said vehicle and a second of said photo-resiStors looking rearwardly of said vehicle, means including in parallel with said first photo-resistor a variable resistance having a value greater than the illuminated resistance and less than the unilluminated resistance of said first photo-resistor, means connecting in series with said second of said photo-resistors, a further resistance having a value less than the unilluminated resistance and greater than the illuminated resistance of said second of said photo-resistors, means connecting said photo-resistors and resistors across a d.c. voltage source, and solid state circuitry responsive to voltage across said first photo-resistor for controlling current to said coil means.
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21. The combination according to claim 20, wherein said coil means is a single coil responsive to currents of opposite directivities in said coil to drive said armature in opposite senses.
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22. A photocell motor control circuit for a day-night mirror comprising, a motor, a first circuit including a first photoelectric cell exposed to ambient light but not to light directed in a predetermined direction, a second circuit including a second photoelectric cell exposed to said ambient light and also to said light directed only in said predetermined direction, a source of voltage providing electric current, means connecting said circuits in series across said source of voltage and providing a junction between said circuits, a bistable transistor circuit having a transistor base connected to said junction, means driving said bistable circuit into one or another of its stable states accordingly as said junction rises or falls to a predetermined level with respect to the level of a pole of said source of voltage, transistor switching circuits for conveying current selectively from said source of voltage to said motor so as to drive said motor in opposition senses, selectively, means responsive to said bistable circuit according to its state to control said transistor switching circuits to convey said current to said motor in said opposite senses, and a reflective panel movable in alternate directions in response to driving of said motor in said alternate senses.
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23. The combination according to claim 22, wherein is provided a resistive circuit connected only across said first photo-electric circuit and having a resistance greater than the resistance of said photoelectric cell when illuminated by said ambient light and less than the resistance of said photoelectric cell when dark.
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24. A photoelectric cell control circuit, comprising means connecting two photoelectric cells in series across a source of voltage to establish a junction between said photoelectric cells which has a voltage determined by the relative intensities of illuminations of said photoelectric cells, a first transistor having a first gate electrode and two further first electrodes, a second Transistor having a second gate electrode and two further second electrodes, means individually connecting said transistors in parallel across said source of voltage via resistances connected directly between said further electrodes and said source of voltage, means connecting said second gate electrode to one of said first further electrodes, means connecting said first gate electrode to said junction, a DC motor, and means responsive to the value of voltage of one of said further second electrodes for driving said motor in alternate senses according as said value is greater or less than a predetermined amount, a mirror panel, and means mounting said mirror panel to move to either of two limiting positions in respect to actuation by said motor in said alternate senses.
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25. A rear view mirror system for a vehicle, wherein a panel is selectively movable between two stable positions relative to said vehicle for providing via said mirror system at a viewing location a relatively bright reflected image in a first position of said panel and relatively weak reflected image in a second position of said panel, said mirror system including a motor, said motor including an armature movable in opposite senses in response to oppositely directed currents applied to said motor means responsive to said armature in moving in said first sense for moving said panel to said first position and responsive to said armature in moving in said second sense for moving said reflective panel to said second position;
- photo-sensitive means for sensing the intensity of light directed toward said reflective panel in comparison with ambient light intensity;
electrical circuit means for directing current through said motor in one direction in response to intensities sensed by said photo-sensitive means below a predetermined intensity, and for directing current through said motor in an opposite sense in response to intensities sensed by said photo-sensitive means above said predetermined intensity.
- photo-sensitive means for sensing the intensity of light directed toward said reflective panel in comparison with ambient light intensity;
Specification