Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02360546 2001-07-25
E
Y~IAGNA REFLEX HOLDING GNlBH
i~IAG 99/0I
The present invention relates to a vehicle exterior
mirror according to the preamble of patent claim 1 and
a method for controlling same according to patent claim
15.
Vehicle exterior mirrors of this type are used for the
motor-operated flapping in and out of a mirror head in
relation to a vehicle chassis. What is achieved by
this means for example is that, as a vehicle is parked,
the exterior mirrors can be laid against the vehicle
chassis in a comfortable manner, and thus the lateral
spatial requirement of the vehicle can be lessened and
damage to the reflective surface of the exterior mirror
can be avoided.
Vehicle exterior mirrors are already known with a
mirror head which may be swivelled in relation to a
a
r
mirror base as well as with a drive and control unit
for the motor-operated swivelling of the mirror head in
relation to the mirror base, the mirror base being
attached to the vehicle chassis, and the drive and
control unit containing at least one position sensor
for detecting the position of the mirror head in
relation to the mirror base. The printed patent
specification US 4626084 describes an exterior mirror,
whose mirror head may be swivelled with the aid of an
electromotor. The swivelling position of the mirror
head may be detected by a plurality of microswitches,
each microswitch being allocated to a specific position
and this position being clearly identified.
Such a device in accordance with prior art has the
disadvantage that, in order to identify clearly the
position of the mirror head, high outlay is necessary.
For each individual position, a separate microswitch is
necessary; this means high material and assembly casts
and involves the danger of high susceptibility to
error. Moreover, the control program for such a mirror
according to prior art is not very convenient, since
especially after a non-motor-operated movement of the
mirror head by external influences, the ~~self-finding "
of the mirror head, i.e. the automatic setting of a
defined position of the mirror head, is uery tedious.
The purpose underlying the present invention therefore
is to create a vehicle exterior mirror and a method for
CA 02360546 2001-07-25
o
8
controlling same, in which the swivelling state of the
mirror head may be recognised in a simple and reliable
manner and thus swivelling the mirror head into a
specific defined position is made possible,
This purpose is fulfilled by a vehicle exterior mirror
according to the preamble of the main claim in
conjunction with the characteristic features of the
main claim, as well as by a method according to claim
15.
Through the fact that the position sensor is designed
as a sensor for distinguishing between end and
intermediate positions, that a normal movement region
of the position sensor is delimited by the end
positions, and that through the drive and control unit
providing a specific drive direction and the position
sensor running through this drive direction until an
end position is reached, a specific end position may be
i
recognised, the constructional outlay for position
sensors can be minimised, particularly where there is a
plurality of end positions. If for example the normal
movement region of the position sensor (and thus also
the normal movement region of the corresponding mirror
head) is delimited by two end positions, it is possible
with a single position sensor, e,g, a microswitch, to
identify clearly a specific end position. The drive
and control unit assumes a specific drive direction for
the mirror head, until the position sensor announces an
CA 02360546 2001-07-25
CA 02360546 2001-07-25
Q
end position. This end position is here clearly
determined by the assumed direction of rotation, for
one end position is exactly allocated respectively to
each of the rotational directions (the end positions
are located on the arc of a circle). Thus for example
a single microswitch in conjunction with a cam disc,
which pre-sets a normal movement range e.g. through
stops, and has in the region of the stops e.g. raised
parts or depressions to characterise end positions, is
sufficient to realise mechanically the recognition unit
according to the invention. Pre-setting a specific
drive direction and allocating this drive direction to
a specific end position, as well as the l~self-finding "
of the mirror head, particularly after non-motor-
operated swivelling, can be realised in a very simple
and low-cost manner through an electronic circuit
realised in the drive and control unit.
Advantageous developments of the present invention are
given in the dependent claims.
one advantageous embodiment provides for stops to be
provided in the region of the end positions, which
stops, during the motor-operated swivelling of the
mirror head, act to block in the direction out of the
normal movement region and do not block in the
direction towards the normal movement region. It is
furthermore advantageous that a drive of the drive and
control unit is attached on the one hand to the mirror
10
head and on the other hand to the mirror base and has a
slip coupling. By this means safety regulations are
taken into account which require swivelling of the
mirror head under the effect of external impact as
well. In interplay with the stops acting on one side
what is achieved is that the mirror head can on one
side be moved out of the normal movement region by the
effect of impact, but it is not possible to leave the
normal movement region through the motor-operated
movement of the mirror head.
Further advantageous developments of the present
invention are given in the remaining dependent claims.
The present invention is now explained with the aid of
several figures. These show:
Fig. la a diagrammatic view of a vehicle exterior
mirror according to the invention, in the
driving position,
Fig. 1b a diagrammatic view of an exterior mirror
according to the invention, in the parking
and overextended position,
Fig. lc a diagrammatic view of the drive and control
unit of a vehicle exterior mirror according
to the invention,
CA 02360546 2001-07-25
CA 02360546 2001-07-25
11
Figs. 2a - 2c flow charts of subroutines of a control
program for the exterior mirror
according to the invention,
Fig. 3 a flow chart of the control program for the
vehicle exterior mirror according to the
invention,
Fig. 4 a function diagram of the control program for
the exterior mirror according to the
invention,
Fig. la shows a vehicle exterior mirror 1 with a mirror
head 3. The mirror head has a reflective surface which
is not represented in detail. The mirror head is
connected to a mirror base 2 via a swivel joint lying
in the region of the drive and control unit 4. The
mirror base 2 is attached to a vehicle chassis 5. The
mirror head 3 is located in the ('driving position "; in
this position the mirror head 3 points substantially
vertically away from the vehicle chassis 5, such that
rear vision is made possible for the driver located in
the interior of the vehicle.
Fig. lb shows two further extreme positions of the
mirror head 3. Here position 15 refers to a 'sparking
position "; in this position the mirror head 3 lies
substantially against the vehicle chassis 5, such that
a reflective surface of the mirror head 3 is protected.
CA 02360546 2001-07-25
i2
Shown in broken lines is the " overextended position "
16, in which the mirror head 3 is flapped into the
drive direction 17 of the vehicle. This position
cannot be achieved by motor-operated movement of the
mirror head 3; it can only be achieved by external
mechanical influences.
Fig. lc shows a diagrammatic view of the drive arid
control unit of a vehicle exterior mirror according to
the invention. The areas which are shaded black, which
in each case connect two components to one another,
refer to a mechanical coupling (attachment).
A cam disc 13 is securely connected to the mirror head
3. The cam disc 13 may be rotated around a joint 18
which is attached to the mirror base 2. A microswitch
6, which is attached to the mirror base 2 engages with
the exterior circumference of the cam disc 13. It is
naturally also possible for the microswitch, in
kinematic inversion of what is shown in this
embodiment, to be attached to the mirror head and the
cam disc to be attached to the mirror base. It is
furthermore possible for the position sensor to be
designed not as a microswitch but as a sensor which has
a measuring principle based on a magnetic field, an
optical measuring principle or one based on the Hall
effect.
CA 02360546 2001-07-25
13
The cam disc 13 has depressions in the region of end
position 7a and 7b. Between these end positions, in
which the microswitch 6 is not triggered, there is
located a section 8a in the form of a circular arc,
which is realised as an 'fintermediate position ", in
which the microswitch 6 is actuated. It is naturally
also possible for the end positions to be raised and
the intermediate positions to be depressed.
The microswitch 6 is designed as a digital switch such
that it can distinguish between « end position " and
'lintermediate position ". A ifnormal movement regions'
of the position sensor is delimited by the end
positions 7a and 7b. Normally the microswitch moves in
the region between the end position 7a (this
corresponds to the driving position 14) and the end
position 7b (this corresponds to the parking position
15).
A drive 10 of the drive and control unit 4, which drive
contains an electromotor, is attached on the one hand
to the mirror head 3 and on the other hand to the
mirror base 2 and has a slip coupling 11. This can be
designed for example as a claw coupling with chamfered
claws. The slip coupling serves primarily two
purposes. on the one hand it ensures that where there
is an external movement of the mirror head 3, the slip
coupling races from a specific torque and thus the
movement of the mirror head in accordance with safety
CA 02360546 2001-07-25
1~
regulations is possible. Moreover, damage to the motor
is avoided by blocking current, if the mirror head 3
should lock (for instance through icing or through
being held).
The normal movement region of the cam disc 13 is
delimited by two stops 9a and 9b, which are
respectively disposed on stops 7a and 7b. The stops
have the characteristic that they have a blocking
effect during motor-operated swivelling of the mirror
head 3 in the direction out of the normal movement
region. This means that the microswitch 6 never leaves
the normal movement region as a result of the drive 10
alone. If however there should be external mechanical
load on the mirror head 3, when a pre--determined limit
moment is exceeded, the microswitch 6 can for example
pass over the stop 9a and assume a position on region
8b of the cam disc. This is the case for example if
the mirror head 3 assumes an overextended position 16
(see Fig. lb). When motor-operated movement is
effected by the drive 14 in direction 12b however, the
region sb, which is realised as an "intermediate
position " (i.e. the microswitch is actuated), can be
left again by sliding on the stop 9a, such that the
microswitch 6 is then located again in the normal
movement region.
The saw-tooth design of stops 9a and 9b in Fig. C
serves the purpose of good pictorialisation. However
CA 02360546 2001-07-25
~5
it is also possible to design the cam disc
substantially circular (with the exception of stops 7a
and 7b) and to attach the stops 9a and 9b, which block
on one side, to another point of the drive.
According to the invention it is possible, using only a
single microswitch 6, to recognise whether the
microswitch 6 is located in end position 7a or the
position 7b or an intermediate position (8a, 8b). To
this end, the drive arid control unit has a unit which
allocates a specific direction of rotation to a
specific end position. For this purpose, after request
by an operator (through the push of a button for
example), the drive and control unit sets a specific
drive direction and runs through this until an end
position is reached by the microswitch 6. If for
example 12a is pre-set as the direction of rotation and
run through and an end position finally reached, end
position '1a is recognised as the end position. In the
same manner, the end position 7b, (i.e. the parking
position 15 see Fig. ib) is allocated to direction of
rotation 12b. Should the mirror head 3 be located in
an end position before a specific drive direction is
given and run through, a circuit of the drive and
control unit ensures that the end position is first
left, since it is not possible to detect in the static
state which end position is present. The drive and
control unit has furthermore a storage device which
stores the most recently determined end position.
CA 02360546 2001-07-25
16
(Whether this end position actually still exists, has
however to be checked by running through a drive
direction to be given, since it is possible that in the
meantime the mirror head has been moved mechanically
into a different position).
The drive and control unit also has a time circuit to
reverse the drive direction 12a or 12b, or to stop the
drive after a period of time, which may be fixed (e. g.
between 50 and 1004 milliseconds), of driving the
mirror head 3 in a direction beyond one of the end
positions 7a or 7b when the microswitch b is located in
the end position. However it is also possible to
provide the drive and control unit with a blocking
current circuit to reverse the drive direction or to
stop the drive in the case of a blocking current which
may be fixed, as the mirror head is driven in a
direction beyond the end positions, when the position
sensor is located in the end position.
In the example detailed below, a control program is
written which controls two vehicle exterior mirrors
(respectively on the driver and the passenger side of
the vehicle chassis). Naturally, however, it is also
possible to steer just one of the mirrors in an
analogous fashion. Here provision can also be made for
the drive and control unit to have an actuating switch,
and to be so designed that after this switch has been
actuated once, both mirrors move into the parking
CA 02360546 2001-07-25
17
position 15 if they were previously both in the driving
position 14, and both travel into the driving position
if they were previously in the parking position or at
least one of them was located outside the normal
movement region, e.g. the overextended position 16,
Moreover, the control system makes it possible for,
when a mirror is flapped forwards (e. g. position 16),
after actuation of the actuating element, the mirror
head 3 to be additionally flapped in the direction of
the parking positian 15, and for here, directly after
the driving position 14 has been passed, the direction
of rotation to be altered for a short time, in order to
press the mirror head 3 against stop 9a, and thus to
guarantee a secure seat which is therefore low in
vibration. It is particularly advantageous that, in
contrast to devices according to prior art, after
swivelling the mirror head 3 into the extended
position 16, it is no longer necessary to drive into
the parking position, in order to lock the mirror head
3 mechanically into place.
The control program for a vehicle exterior mirror
according to the invention, as per Fig. 3 is explained
in detail below. Reference is made here to the
subroutines shown in Figs. 2a - 2c. The steering of
the vehicle exterior mirror by the operator comes about
through a simple actuating switch, which belongs to the
drive and control unit. In a normal case, by this
means the mirror head 3 is moved, by pressing the
CA 02360546 2001-07-25
18
button once, alternating between the driving position
1~ and the parking position 15.
The subroutines describe individual routines which are
required again and again.
In Fig. 2a is described a routine for " travelling
free ". This is used when the position sensor in the
initial position notifies an end position and it is
necessary to leave this end position, i.e. " travel
free" .
Fig. 2b describes the routine " travel" . This is used
when the position sensor has travelled free and is
making for the next end position.
Finally the routine " block ", shown in Fig. 2c, ensures
that the position sensor or mirror head which has been
moved into the end position is stopped in the new end
position.
The control program according to Fig. 3 is explained
below with the aid of individual examples. For the
mechanical representation of the processes, reference
is here made to Fig. lc. In all the diagrams Y means
' l yes" and N means "no" .
Example a):
CA 02360546 2001-07-25
L~
The mirror head 3 is located in the driving position
and is to be moved into the parking position:
At the beginning of the control program " additional
flapping control system ", first of all markers " travel
error " for travel errors which have occurred and
" manual" for the manual disengagement of the mirror
head 3, i.e. the non motor-operated movement of the
mirror head 3~ are reset. After using the actuating
switch " wait for pressing of button " the program
checks whether the drive and control unit has stored
the t'driving position " (position 14 in Fig. 1a) as the
last position of the two vehicle exterior mirrors.
This is the case in the present example.
Then an inquiry is made as to whether both mirrors are
in an end position, i.e. in position 7a or 7b see Fig.
lc). If this is not the case, a manually deflected
exterior mirror is assumed; this case will be discussed
later (under c). In the present case it is assumed
that both exterior mirrors are actually in the driving
position, i.e. the position sensor 6 is in notch 7a.
Then the subroutine "travel free" see Fig. 2a is run
through. This happens in the "flapping in " direction
i.e. in direction 12b, towards the parking position
(see 15 in Fig. lb).
In the subroutine " travel free ", first of all the
marker for " travel error " is reset again. Moreover.a
CA 02360546 2001-07-25
marker for '°switching time " is reset (here it is a
question of a higher order time loop, which e.g, when
the drive is blocked after a time to be pre-set, e.g.
10U0 milliseconds, switches off the power supply of the
drive, in order to avoid any damage by blocking current
load . Then an inquiry is first made as to whether the
microswitch 5 is still located in an end position (here
end position ?a according to Fig. lc). This is the
case. Now a check is made in a time loop, as to
whether the position sensor leaves the end position
within the maximum switching time (this is recognised
in Fig, lc by '~pressing in" of the microswitch) . If
this is not the case, i.e. if there is no movement of
the mirror head 3 when the motor is switched on, a
marker for " travel error " is set and the motor
switched off. If there is a change, i.e. the end
position is left, the drive remains switched on for an
additional 50 milliseconds, so that the microswitch in
each case leaves the end position and does not fail
back into same. Then the motor is again switched off.
Now in Fig. 3 an inquiry is made as to whether both the
vehicle exterior mirrors are located in an intermediate
position. If this is not the case, one has to proceed
from a mechanical disengagement, such that a marker for
~'manual" is set. If both the mirrors are located in
the intermediate position, i.e. in section 8a on Fig.
lc, the subroutine " travel" is chosen. Here the motor
drive comes about in the direction of " flapping in "
CA 02360546 2001-07-25
21
i.e, in direction 12b. In the parking position, into
which a movement in direction 12b here leads, a so-
called " extra block " is dispensed with; this is used
if the mirror head is disengaged manually.
In the routine " travel" according to Fig. 2b, first of
all the marker for " travel error " is reset. Moreover
a marker for " travel time " is reset (here it is again
a higher order time loop to prevent any damage to the
motor by blocking current load, this can be fixed for
example at 1000 milliseconds). Then the motor is
switched on, such that the mirror head 3 moves in
direction 12b. Subsequently an inquiry is made as to
whether both vehicle exterior mirrors are located in an
end position. This happens over the duration of a
"travel time " time loop. If within the maximum travel
time both the exterior mirrors have nat reached an end
position, a marker for "travel error" is set. If an
end position is reached, i.e. if it can be assumed that
the microswitch 6 is located in position 7b (see Fig.
lc), the subroutine " block " is called up.
The subroutine " block " according to Fig. 2c begins
with a " blocking time " (again a higher order time
loop) being reset. Then travel is carried out towards
the stop 9b (the motor is still switched on and runs on
in direction 12b). This blocking time, e.g. 100
milliseconds, happens only to brace the drive mechanism
(this causes travel with less vibration). After this
CA 02360546 2001-07-25
blocking time has expired, an inquiry is made as to
whether the marker has been set " to manual". This not
being the case, the subroutine 'ltravel" according to
Fig. 2b is branched back to, and the motor is switched
of f . Final ly in the main program accarding to Fig . 3 ,
an inquiry is made as to whether there was a travel
error. If this was the case, the beginning of the
program is branched back to. If there was no travel
error, " parking position " (see position 15 in Fig. lb)
is stored in the drive and control unit as the
position.
Example b):
The mirror head 3 is located in the parking position
and is to be brought into the driving position:
According to Fig. 3, in the main program " additional
flapping control" first of all there is a restoration
of the markers for ~~manual" and "travel error" . As a
result of the pressing of a button, an inquiry is made
to see whether the last position was a l'driving
position " (position 14). This is not the case here
since a parking position (position 15, the microswitch
6 is located in depression 7b) is present. Thereafter
an inquiry is made as to whether both exterior mirrors
are in an end position. If both are in a correct
parking position, this is then the case. Thereafter a
subroutine j'travel free from the end position (flap
CA 02360546 2001-07-25
out)" is started. ~jFlap out' here means the movement
direction 12a in Fig, lc, In the manner described
above, according to Fig. 2a the end position 7b is left
in this direction, such that the microswitch 6 is
triggered and is located in the intermediate position
8a.
Thereafter an inquiry is made as to whether both the
exterior mirrors are in an end position. This is not
the case here since the microswitch 6 is located in an
intermediate position (if the mirror head 3 were
already in the end position, i.e, the driving position,
ifblocking~l according to Fig, 2c would tension the
mirror head in the driving position). Here however
the mirror head 3 is so moved that the intermediate
i5 position region 8a is travelled through by the mirror
head 3 being moved in direction 12a. 1~t the end of the
travel process, which is initiated by reaching the end
position 7a, there is then an ~~extra block~r of the
mirror head 3. This increased blocking (achieved by a
longer blocking timed serves to tension the mirror head
particularly strongly in the driving position in order
to produce low vibration in the travel drive. If this
comes about without any travel error, the t~driving
position " is stored as the last position. If there is
a travel error, for example if there is a corresponding
error indication in the vehicle display panel, the
operator can then start a new attempt in addition,
CA 02360546 2001-07-25
Example e);
The mirror head 3 is disengaged manually, the parking
position was stored as the last position and the mirror
head is to be brought into the driving position.
In the main program according to Fig. 3 first of all
the markers for 'lmanual~l and " travel error " are
reset. In response to the operator pressing a button
an inquiry is made as to whether the last position was
a driving position. since the parking position was
stored as the last position, there is a negative
answer. Then an inquiry is made as to whether it is an
end position. Here it is assumed that the mirror has
been brought manually into the overextended position
(see position 16 in Fig. 1b). Since the microswitch 6
in this case is located in the intermediate position
region 8b, the question about the end position is
replied to in the negative.
Thereafter the marker for f'manual~~ :is set (i.e. the
mirror head has not been swivelled by the motor,
however the slip coupling is meanwhile in engagement
again since after overload it always falls back again
into the power-transmitting position). Then the
subroutine " travel~f according to Fig. 2b is started.
This happens in the direction "flap in" , i.e. in the
direction 12b. The mirror head 3 travels according to
Fig. 2b until it has reached an end position within the
CA 02360546 2001-07-25
maximum travel time admissible. This is in the present
case the end position 7a (reaching this end position is
quite easily possible from region 8b towards the end
position 7a since stop 9a only acts in the opposite
5 direction to block the drive). The mirror head is then
moved during the " blocking timer' further in direction
12b. If there is here no travel error, the " parking
position " is stored as the last position. Hereafter
there is again a move towards the subroutine " travel"
10 according to Fig. 2b.
This runs in the direction 'flap out " i.e. in
direction 12a. The travel continues here until both
mirrors have reached the end position, i.e. the driving
position 14 (see Fig. la) (this happens within the very
15 shortest time since the microswitch 6 was previously
located in the immediate proximity of stop 9). Once
the end position 7a (see Fig. 2b) has been reached,
there is a move toward subroutine " blocky', see Fig.
2c. Here there is first of all a restoration of the
20 blocking time and running through the standard blocking
time, The inquiry re " manual" is given a positive
answer (a marker was set above). Thus an " extra
block " is made possible. Thereafter there is renewed
restoration of the blocking time and the running
25 through of an " extra blocking time " which is longer
than the normal blocking time. The normal blocking
time serves primarily to slightly tension the drive
mechanism in order to exclude damage or noise from
CA 02360546 2001-07-25
~6
vibration. The extra blocking time, which is longer
than the normal blocking time, serves to tension the
mirror head 3 particularly strongly in the driving
position 14. once this extra blocking time has been
run through, during which the microswitch 6 has run
against stop 9a, there is a return from the subroutine
according to 2c to the subroutine according to Fig. 2b,
the motor i s st,rit ched of f and there i s a return to the
main program. Since in the sequence described above no
travel error was recognised, the "driving positionr~ is
stored as the last position, i.e. the position in which
both exterior mirrors are located at that time.
The three sample cases described above deal with
particularly significant positions which describe the
whole spectrum of possibilities for controlling the
course of the vehicle mirror according to the
invention. In addition to this, however, there are
further possible sequences which however are clear to
any expert from the above explanations with the aid of
the flow charts given.
Finally a reference is made to Fig. 4 which in self-
explanatory fashion describes the diagrammatic
structure of the sequence program according to Fig. 3.
