Automatic dimming switch for a vehicle illuminated visor

A covered illuminated vanity mirror for use in a vehicle includes a cover operated switch for actuating lights for providing illumination for the mirror. A second switch is provided and is movable for selecting high or lower levels of light intensity. To assure the level of illumination is at the lower level when the cover is initially opened, an automatic dimming system couples the second switch to the cover such that movement of the cover between an open position to a closed position causes the second switch to move to the lower intensity position.

BACKGROUND OF THE INVENTION 
The present invention relates to illuminated, covered vanity mirrors 
installed in a vehicle, and particularly to an automatic dimming switch 
therefor. 
An illuminated vanity mirror built within the body of a visor has become a 
popular accessory on many vehicles and standard equipment on several 
vehicle models. The visors provide the normal sun blocking function and in 
addition, provide a vanity mirror which can be illuminated for use under 
low ambient conditions. The mirror is covered by a protective cover to 
conceal the mirror when not in use. Such visor construction is disclosed 
in U.S. Pat. No. 4,227,241, issued Oct. 7, 1980 and entitled VISOR 
ASSEMBLY. 
In such visor construction, lights adjacent the mirror are activated by the 
opening of the cover and a manually operated bright/dim switch is provided 
for providing two levels of illumination. When the bright/dim switch is 
left in the bright, or higher illumination level position, opening of the 
cover within the darkened interior of a vehicle can provide a level of 
illumination which may cause temporary night blindness and discomfort to 
the user. Frequently, the mirror will be illuminated at the higher level 
of illumination by a prior user, who does not return the switch to the low 
level position when use is discontinued. Due to the automatic 
extinguishing of the light means upon closing of the cover, the problem 
occurs relatively frequently. 
U.S. Pat. No. 4,227,242 discloses a cover actuated switch by which the 
level of illumination is controlled by the cover to initially provide a 
low level of intensity and subsequently a higher level as the cover is 
moved to a second position. Although this structure will, if the cover is 
controlled manually between different positions, reduce undesired night 
blindness by initially actuating the light source in a low intensity 
position, it requires the user to actively control the cover position 
instead of merely flipping open the cover as is typical. Also, although 
bright and dim levels of illumination is provided, they cannot be manually 
selected except by movement of the cover. Thus, the system does not employ 
a separate and distinct manually operated intensity level controlling 
switch but relies on the mirror cover position control. 
SUMMARY OF THE PRESENT INVENTION 
The system of the present invention overcomes the night blindness and 
discomfort caused by the operation of the visor illumination means in the 
high brightness mode by providing an automatic dimming switch activated 
upon movement of the cover from an open to a closed position which 
automatically provides a lower level of illumination upon reopening of the 
cover and activation of the light means. In a preferred embodiment of the 
present invention, a bright/dim switch is provided for allowing a user to 
manually switch between bright and low level intensities and means 
coupling the cover to the switch are provided for returning the switch to 
the low level intensity position upon closing of the cover. 
In a preferred embodiment of the invention, a mechanical dial cord is 
coupled between a movable element on the cover assembly and the switch for 
physically moving the switch to the dim position upon movement of the 
cover from an open to a closed position in the event the switch has been 
manually moved to a bright position. 
With such construction, when the visor cover is opened, the illuminated 
mirror will always be illuminated initially at a low level intensity 
thereby obviating the night blindness and discomfort attendant to 
switching from a darkened condition to a high intensity illumination 
condition when the switch would otherwise be left in a high intensity 
position. 
These and other features, objects and advantages of the present invention 
will become apparent upon reading the following description thereof 
together with reference to the accompanying drawings in which:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring initially to FIGS. 1 and 2, a visor 10 is disclosed incorporating 
the present invention and is shown mounted on the passenger, or right, 
side of a vehicle 11 such as an automobile. The visor comprises a visor 
body 12 made of a core member injection molded of suitable polymeric 
material such as polypropylene and including a central, rectangular recess 
formed in the rearward facing side when the visor is lowered for receiving 
an illuminated visor mirror frame mirror assembly 20. The visor core is 
covered by a suitable upholstery material 13 to conform the visor 
appearance to that of the vehicle's interior. A visor rod mounting 
mechanism extends within the visor body along the top edge thereof and 
includes an elbow bracket assembly 25 for mounting one end of the visor to 
the vehicle for pivoting between a raised, stored position and a lowered, 
use position, illustrated in the Figures. The opposite, or left, end of 
the visor shown includes a post (not shown) which releasably fits within a 
socket 26 permitting movement of the visor body from the windshield area, 
illustrated in the Figures, to the side of the vehicle, as desired. 
The visor mirror assembly 20 comprises a generally rectangular frame 22 
having a central, rectangular opening 23 behind which there is mounted a 
mirror 24 (FIG. 2). The frame 22 integrally includes a peripheral trim 
flange 25' which surrounds the frame and extends over the edge of the 
recess formed in the visor body when assembly 20 is mounted, as shown in 
FIGS. 1 and 2. On opposite sides of opening 23 and mirror 24, there is 
provided a pair of vertically oriented, rectangular openings 26 for 
receiving snap-fitted lenses 27. Lamps are positioned behind the lenses, 
as described below, for directing illumination toward the face of the user 
to permit use of the mirror 24 under low ambient light conditions. A cover 
30 is pivotally coupled to frame 22 and is held in a closed position, as 
illustrated in FIG. 1, or an open position, as illustrated in FIG. 2, by 
an over-center spring construction, partially illustrated in FIGS. 3 and 
5. The cover mounting structure includes a pair of tension springs 32 at 
opposite sides of the cover. Each spring has one end 33 anchored through 
an aperture in a corner 34 of cover 30 and an opposite end anchored to a 
post 36 located on the rear side of flange 25'. Cover 30 and frame 22 
include a snap-in socket and pin assembly 37 for pivotally intercoupling 
the cover to the frame at opposite upper edges of the cover. This 
construction is described in greater detail in U.S. Patent application 
Ser. No. 646,476, filed Feb. 7, 1983, and entitled VISOR COVER ASSEMBLY, 
the disclosure of which is incorporated herein by reference. 
As best seen in FIGS. 2 and 7, mounted to the lower, righthand corner of 
frame 22 is a single-pole single-throw slide switch 40 which includes a 
stem 42 (FIG. 7) extending outwardly through a slot 39 on the face of 
frame 22 below the rightside lens 27. Switch 40 is employed, as best seen 
by the circuit diagram of FIG. 8, for activating a pair of lamps 50 and 52 
which are wired in series with one another, as seen, with the combination 
coupled in parallel with lamps 51 and 53 when switch 40 is in a closed 
position. 
A cover actuated switch 54 (FIG. 8) couples lamps 51 and 53 to the vehicle 
operating power source, such as battery 55, by a suitable wiring harness, 
illustrated schematically as conductors 56 and 57 typically coupled to the 
battery through the vehicle's instrument panel in a conventional fashion. 
Thus, switch 54 operates to close when cover 30 is moved from a closed 
position, shown in FIG. 1, to an open position, shown in FIG. 2, to apply 
power to the parallel circuit of lamps 51, 53 and 50, 52. As can be 
appreciated, when the bright/dim switch 40 has been manually moved to the 
closed position, all four lamps will simultaneously actuate. To prevent 
initial actuation in this high intensity mode in which four lamps are 
actuated, the automatic dimming means of the present invention is 
employed. 
The structure for assuring switch 40 is moved to the low intensity open 
position when the cover is closed includes, in the preferred embodiment, 
means 60 for mechanically moving switch 40 from a closed position to an 
open position when the cover is closed. As can be seen with reference to 
FIG. 7, switch 40 is a slide switch with stem 42 being coupled to a 
generally U-shaped switch body 44 made of a nonconductive plastic 
material. Body 44 supports a shorting conductive strip 45 which moves 
between the position shown in FIGS. 3 and 7, shorting out conductive 
elements 58 and 59 which couple lamps 50, 52 in parallel with lamps 51, 53 
in the high intensity position. Switch 40 moves to the right, as shown in 
FIGS. 5 and 7, (to the left in FIG. 2) to open and decouple lamps 50 and 
52 in the low intensity position. In order to assure the switch always 
moves from the high intensity closed position to the low intensity open 
position a dial cord 62 couples the switch to the cover. Cord 62 is made 
of a suitable, low stretch, polymeric material, such as NYLON and is 
anchored at one end 63 to one leg of the switch body 44 by means of 
extending the dial cord through an aperture and knotting the cord to the 
body 44 of the switch, as illustrated in FIG. 7, or by other suitable 
anchoring means. 
The dial cord 62 extends along the lower edge and behind frame 22 through a 
cheek block 64 mounted to the rear of a circuit panel 28 for changing the 
direction of the dial cord 62 toward the top edge 31 of cover 30. Block 64 
includes a bail 65 for constraining cord 62 therein. The end 68 of cord 62 
is then secured to a mounting boss 69, integrally formed on the edge 31 of 
cover 30 by tying or other suitable means. If desired, a suitable tension 
spring 67 can be inserted in series with cord 62, as indicated in FIG. 3, 
to take up any slack in the cord. 
The operation of the automatic dimming system can best be understood by 
reference initially to FIGS. 3 and 4 which show the switch in a selected 
high position for providing higher level illumination during use of the 
mirror and the cover 30 in an open position. In this position, switch 40 
is closed and moved to the leftmost position in FIG. 7, and boss 69 on 
edge 31 of the cover is lowered somewhat from the top edge of the frame 
22. In this position, dial cord 62 is held taut by spring 68 but does not 
exert a force on switch 40 sufficient to cause it to move from the 
selected high position. 
As the cover is moved from the open position, shown in FIGS. 3 and 4, to a 
closed position, shown in FIGS. 5 and 6, boss 69 moves upwardly in a 
direction indicated by arrow A in FIGS. 4 and 6 through a distance of 
approximately 3/8 of an inch. This, in turn, moves dial cord 62 about 
cheek block 64 an equivalent distance causing switch 54 to be moved to the 
right, as illustrated in FIGS. 5 and 7. This causes switch 40 to open, 
disconnecting lamps 50 and 52 such that when the cover is opened and 
switch 54 closed, only the low intensity lamps 51 and 53 will be 
activated. When the cover is opened, mounting boss 69 moves downwardly in 
a direction opposite arrow A reducing the tension on dial cord 62 a 
sufficient amount to allow the user to move switch 40, if desired, to a 
high intensity position. Naturally, if switch 40 is left in the low 
intensity position, the automatic dimming mechanism 60 does not operate to 
change its position. 
It will become apparent to those skilled in the art that various 
modifications to the preferred embodiment of the invention can be made 
without departing from the spirit or scope of the present invention as 
defined by the appended claims.