Electricity: motive power systems – Positional servo systems – Program- or pattern-controlled systems
Patent
1989-03-31
1991-01-15
Shoop, Jr., William M.
Electricity: motive power systems
Positional servo systems
Program- or pattern-controlled systems
350281, 350279, 350278, G05B 1910
Patent
active
049856677
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a device for pivoting a motor-vehicle mirror from the normal position (fully-reflecting condition V) to a non-dazzle position (partly-reflecting condition T) in the event of excessive glare (B) from the headlight of a following vehicle and taking into account any interference from ambient light (U), said device comprising a voltage-source, a motor (M), the shaft (10) of which acts upon the mirror through a tilting mechanism and which is fed from thyristors (T1 and T2) which are, in turn, controlled by transistors (TR1, TR2 and TR3) with the aid of photodiodes or photoresistors (B and U) for glare and interference from ambient light.
Automatically adjustable rear-view mirrors for motor-vehicles are known (German OS No. 34 37 775). In the known rear-view mirror a mirror accommodated in a housing is pivoted from a normal position with high reflection to a non-dazzle position with reduced reflection by means of an electric motor. Its drive shaft is connected to the mirror by a transmission. The transmission is in the form of a worm drive through which the drive shaft drives a shaft bearing a cam for driving a switch. It is connected to at least one eccentric part which is guided displaceably in the housing in a guide running in lateral direction to the axis of the shaft. In order to take ambient light into account, an electrical bridge-circuit is provided which feeds the motor through a comparison of the (electrical) glare- and ambient-light-signals and an amplifier. Neither the electric circuit, nor the drive mechanism meets the existing requirements of pivoting devices for motor-vehicle mirrors, since the electronic circuit responds merely to the ratio between glare and ambient light and because many mechanical parts must be accelerated and braked in order to adjust the mirror and it is not even possible to bring the mirror exactly to its terminal position, a fact attributable to, among other things, the run-on properties of the motor and the transmission, but also to the elongated hole by means of which rotary motion is converted into tilting motion. In addition to this, the electronic circuit is extremely complex and costly.
It is an object of the invention to design a device of the type mentioned at the beginning hereof in such a manner that the electronic circuit thereof responds to the absolute magnitude of incident light (glare, ambient light), while the mechanism consists of only a few and relatively small mechanical parts for pivoting the mirror.
One particular advantage of the invention is that it provides, with few electronic components, a circuit which responds to absolute magnitudes and controls the motor in such a manner that it comes to a stop at stable terminal positions and even motor and transmission run-on cannot cause the mirror to shift ("flutter"). This is aided by the transfer mechanism of the device according to the invention, whereby the rotary motions of the motor are converted into pivoting or tilting motions. The device according to the invention responds to a specific amount of glare and shifts the mirror from the normal position (V) to the non-dazzle position (T) unless a specific amount of ambient light is also present. This allows suitable amounts of light to be established for the response, without the mutual ratio of these magnitudes being of importance as in the known bridge-circuits.
An example of embodiment of the invention is explained hereinafter in conjunction with the drawings attached hereto, wherein
FIG. 1 a circuit for the device according to the invention;
FIG. 2 parts of the tilting mechanism for the device according to the invention;
FIG. 3 is a cross-section along the line III--III in FIG. 2.
FIG. 1 shows an example of embodiment of a circuit according to the invention.
The circuit is connected to the positive and negative poles of a source of direct voltage, for example the 12V direct voltage of a motor-vehicle. The circuit can be switched-on or switched-off by means of a main switch HS, so that the device according to the invention can
REFERENCES:
patent: 4443057 (1984-04-01), Bauer et al.
patent: 4580875 (1986-04-01), Bechtel et al.
patent: 4838650 (1989-06-01), Stewart et al.
Bergmann Saul M.
Brinckmann Frank
Shoop Jr. William M.
LandOfFree
Device for pivoting a motor-vehicle mirror from the normal posit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for pivoting a motor-vehicle mirror from the normal posit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for pivoting a motor-vehicle mirror from the normal posit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-56964