U.S. patent application number 09/780628 was filed with the patent office on 2001-10-11 for motor vehicle door lock and process for its control.
Invention is credited to Koerwer, Matthias.
Application Number | 20010028232 09/780628 |
Document ID | / |
Family ID | 7630603 |
Filed Date | 2001-10-11 |
United States Patent
Application |
20010028232 |
Kind Code |
A1 |
Koerwer, Matthias |
October 11, 2001 |
Motor vehicle door lock and process for its control
Abstract
The present invention is directed to a motor vehicle door lock
such as a side door lock, a rear door lock, a rear hatch lock, or a
hood lock and a process for controlling such a motor vehicle door
lock, wherein the lock includes an electric motor drive for
reaching a set position depending upon at least one start-up
characteristic acquired when the electric motor drive is actuated
and is at least one of shut off and short circuited prior to a set
position in time and space.
Inventors: |
Koerwer, Matthias;
(Wuppertal, DE) |
Correspondence
Address: |
NIXON PEABODY, LLP
8180 GREENSBORO DRIVE
SUITE 800
MCLEAN
VA
22102
US
|
Family ID: |
7630603 |
Appl. No.: |
09/780628 |
Filed: |
February 12, 2001 |
Current U.S.
Class: |
318/445 |
Current CPC
Class: |
Y10T 292/1082 20150401;
E05B 81/06 20130101; E05B 81/14 20130101; Y10S 292/66 20130101;
Y10T 292/699 20150401; E05B 81/64 20130101; Y10S 292/03
20130101 |
Class at
Publication: |
318/445 |
International
Class: |
H02P 001/00; H02P
003/00; G05B 005/00; H02P 007/00; H02H 007/08 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 11, 2000 |
DE |
1 00 06 118.4 |
Claims
I claim:
1. A motor vehicle door lock comprising: an actuating element; an
electric motor drive for engaging and positioning said actuating
element; a sensor electrically connected to said electric motor
drive for acquiring at least one of an angular position and angular
velocity of at least one of said electric motor drive and said
actuating element; and control means for controlling said electric
motor drive based upon signals received from said sensor, said
control means establishing a desired set angular position of said
electric motor drive by at least one of turning off and short
circuiting said electric motor drive at a shut-off point that
precedes the set angular position in time and position, wherein at
least one start-up characteristic of at least one of said electric
motor drive and said actuating element is acquired by said control
means for at least one of establishing and correcting the shut-off
point.
2. The motor vehicle door lock as claimed in claim 1, wherein said
actuating element is a drive roller.
3. The motor vehicle door lock as claimed in claim 1, wherein said
actuating element is a detent pawl
4. The motor vehicle door lock as claimed in claim 1, wherein said
actuating element is a lock latch.
5. The motor vehicle door lock as claimed in claim 1, wherein at
least one of an angular displacement, time correlated to the
angular displacement, angular speed and angular acceleration of at
least one of said electric motor drive and said actuating element,
a predetermined time after actuation of said electric motor drive,
power consumed by said electric motor drive, and a voltage applied
to said electric motor drive are determined as start-up
characteristics.
6. The motor vehicle door lock as claimed in claim 5, wherein the
temperature of said electric motor drive is at least one of
determined and approximated based upon at least one of the angular
speed and angular acceleration of at least one of said electric
motor drive and said actuating element, and the voltage applied to
said electric motor drive when said electric motor drive is
actuated.
7. The motor vehicle door lock as claimed in claim 6, wherein the
shut-off point is established based upon the temperature of said
electric motor drive.
8. The motor vehicle door lock as claimed in claim 7, wherein the
shut-off point is established via at least one of a braking
distance and a braking time of said electric motor drive based upon
the set position, and wherein the braking distance or the braking
time is determined based upon at least one of a start-up
characteristic and the temperature of said electric motor drive
derived from said start-up characteristic.
9. A process for controlling a motor vehicle door lock having an
electric motor drive for an assigned actuating element, said
process comprising the steps of: establishing a set position for
said electric motor drive by at least one of shutting off and short
circuiting said electric motor drive at a shut-off point which
precedes the set position in time and position, acquiring at least
one start-up characteristic for at least one of said electric motor
drive and said actuating element for at least one of establishing
and correcting the shut-off point of at least one said electric
motor drive and said actuating element of wherein.
10. The process as claimed in claim 9, wherein at least one of a
distance traveled and an angular displacement of said electric
motor drive, elapsed time, speed and acceleration of at least one
of said electric motor drive and said actuating element, a
predetermined time after start-up of said electric motor drive,
power consumed by said electric motor drive, and a voltage applied
to said electric motor drive are determined as a start-up
characteristic.
11. The process as claimed in claim 10, wherein a temperature of
said electric motor drive is at least one of determined or
approximated using the speed and acceleration of at least one of
said electric motor drive and said actuating element, the voltage
applied to said electric motor drive upon actuation of said
electric motor drive.
12. The process as claimed in claim 11, wherein the shut-off point
is established based upon at least one of the determined or
approximated temperature of said electric motor drive.
13. The process as claimed in claim 12, wherein the shut-off point
is established via at least one of a braking distance and a braking
time of said electric motor drive, based upon the set position,
wherein at least one of the braking distance and the braking time
is determined based upon at least one of a start-up characteristic
and the temperature of said electric motor drive derived from said
start-up characteristic.
14. The process as claimed in claim 13, wherein at least one
start-up characteristic is acquired each time said electric motor
drive is engaged.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention pertains generally to a motor vehicle door
lock such as a side door lock, a rear door lock, a rear hatch lock,
or a hood lock and a process for controlling such a motor vehicle
door lock.
[0003] 2. Description of the Related Art
[0004] A motor vehicle door lock with the initially mentioned
features is known from practice. Such a motor vehicle door lock has
an electric motor drive for an assigned actuating or locking
element of the motor vehicle door lock. The motor vehicle door lock
further includes a sensor for acquiring the position, such as the
rotary position, of the drive or the assigned actuating element,
and a control means for positioning the drive or the actuating
element in a set position and shutting off or short circuiting the
drive at a shut-off point which precedes the set position in time
and position. The electric motor drive at the shut-off point has a
certain energy of motion which leads to a not inconsiderable
slowing down, therefore, to further move until the drive, and thus,
the actuating element stop. Accurate positioning of the actuating
element in the set position is, however, only possible if the
actual slowing down is considered when the shutoff point is
established. It has been found in practice that the slowing down
depends upon various influences such that the positioning accuracy
is adversely affected thereby.
SUMMARY OF THE INVENTION
[0005] An object of the invention is to provide a motor vehicle
door lock with an electric motor positioning drive and a process
for the control thereof so that accurate positioning under various
operating conditions is easily and economically possible.
[0006] This object is achieved so that at least one of a start-up
characteristic of the drive and a start-up characteristic of the
assigned actuating element when the drive is actuated (turned on)
is acquired or determined and that at least the start-up
characteristic is used to establish a shut-off point which precedes
the set position in time and position. Therefore, the start-up
behavior of the drive can also be used to draw conclusions about
the braking behavior of the drive, thus, without using an
additional sensor, enhanced and more accurate characterization of
the operating behavior of the drive and its electric motor is
possible.
[0007] In general, a plurality of different start-up
characteristics can be determined. In an exemplary embodiment of
the invention, the voltage which is applied to the drive or its
electric motor when the drive is actuated is acquired as a first
start-up characteristic, at least if it can vary, and at least one
of the initial speed, acceleration and values of at least one of
the drive and the assigned actuating element which correspond
thereto and/or which are derived therefrom is acquired as a second
start-up characteristic. It has been found that by means of these
start-up characteristics, the required time or positional setting
of the shut-off point in advance of the set position which is to be
assumed in the shut-off state can be established or determined.
This is explained by the fact that from the two indicated start-up
characteristics, the temperature of the drive, which has a major
effect upon its braking and shut-off behavior, can be estimated or
approximately determined using these start-up characteristics.
Accordingly, depending upon the estimated temperature or the
aforementioned start-up characteristics, the advanced positioning
of the shut-off point which is necessary for accurate positioning
can be ascertained.
[0008] Other details, features, objectives and advantages of this
invention are detailed below using the drawings of one preferred
embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 shows a schematic of a motor vehicle door lock in
accordance with the invention; and
[0010] FIG. 2 shows a schematic of the determination of the
shut-off point.
DETAILED DESCRIPTION OF THE INVENTION
[0011] And now to the drawings, in which FIG. 1 shows a motor
vehicle door lock 1 in accordance with the present invention
including a housing 2 (indicated by the broken line) and an
electric motor drive 3. The drive 3 comprises an electric motor
(not shown) and an adjoining transmission such as a worm gear 4.
The drive 3 acts on or engages a locking or actuating element 5 of
the motor vehicle door lock 1 for positioning the actuating element
5 in at least one set position. The locking or actuating element 5
represents one part of a conventional lock mechanism of the motor
vehicle door lock 1 and acts on or engages a detent pawl 6 which is
used to secure the assigned lock latch 7 of the motor vehicle door
lock 1. Moreover, the locking or actuating element 5 may also
assume additional functions, and optionally, several actuating
functions, and may be positioned especially in the latter case in
several set positions.
[0012] The motor vehicle door lock 1 furthermore includes a sensor
8 electrically connected to the electric motor drive 3 for
acquiring at least one of an angular position and angular velocity
of at least one of the electric motor drive 3 and said actuating
element 8. The sensor 8 may also be integrated into the drive 3.
The sensor 8 is made as an incremental detector for acquiring the
angular position of the actuating element 5, the electric motor and
the worm gear 4. The sensor 8, however, can also be formed by some
other means for acquiring, or optionally, indirectly determining at
least one of the actuating or rotary position, the speed and the
acceleration of at least one of the drive 3 and the actuating
element 5. For example, the sensor 8 may also be a Hall sensor or a
plurality of Hall sensors or at least one microswitch or the
like.
[0013] The motor vehicle door lock 1 further includes a control
means 9 for controlling the drive 3, for example, for actuating
(and shutting off) the drive 3. The control unit 9 may be connected
via a terminal 10 to the motor vehicle electronics (not shown), for
example, a central interlock system, and/or an actuating switch.
The sensor 8 is electrically connected to the control means 9 so
that the control means 9 can acquire or at least indirectly
determine at least one of the position and the speed of the
actuating element 5 and/or the drive 3. Positioning in the desired
set position is detailed below using FIG. 2. The actuating element
5 is preferably disk-like and has a journal-like function element
11 which projects in the axial direction of the actuating element 5
and swivels a detent pawl 6 depending upon the rotary position of
the actuating element 5.
[0014] As shown in FIG. 2, to position the actuating element 5 or
the function element 11 in a set position 12, such as a desired
angular position, for the direction of motion or rotation 13 of the
actuating element 5, the drive 3 or its electric motor is turned
off at a shut-off point 14, and, depending upon the type of drive 3
or the electric motor and the desired braking, is preferably
short-circuited. The shut-off point 14 is placed in advance of the
set position 12 either positionally by the braking distance or the
braking angle 15 against the direction of motion or rotation 13 of
the actuating element, or in time by the braking time. The braking
distance or braking time which is required by the drive 3 or the
actuating element 5 after the drive 3 is shut off, therefore,
starting from the shut-off point 14, depends upon slowing down the
drive 3 and the actuating element 5 after the drive 3 is shut off.
The shut-off point 14 can therefore be determined by the interval
in time or space from the set position 12, depending upon how the
control means 9 functions.
[0015] An advantageous aspect of the approach in accordance with
the present invention lies in that when the drive 3 is actuated
(turned on), or, in the immediately subsequent (start-up) phase,
the control means acquires at least one start-up characteristic
which at least indirectly characterizes the operating state of the
drive 3 or its electric motor. This start-up characteristic, which
is re-determined preferably for each turn-on or start-up, is
subsequently used to fix, vary or correct the shut-off point 14.
Preferably, the start-up characteristics are acquired or updated
each time the drive 3 is actuated (turned on). However, acquisition
can be repeated only when a stipulated minimum time has transpired.
The expression "start-up characteristic" should be understood by
those skilled in the art in the sense that at least one parameter
is encompassed which allows characterization of the starting
behavior of the drive 3 which depends upon the current operating
state. In addition, several start-up characteristics can also be
acquired.
[0016] In accordance with the present invention, a start-up
characteristic such as distance or the angular displacement by the
drive 3 or the actuating element 5 in a definable time from the
actuation (start-up) or engagement of the drive 3 may be acquired.
Alternatively, a start-up characteristic such as the time necessary
for a certain distance traveled or a certain angular displacement
may be acquired. One such start-up characteristic in combination
with the voltage applied to the drive 3 allows for accurate
determination or approximation of the temperature of the drive 3.
Since heat has a major effect upon the braking behavior or the
slowing down of the drive 3 and of the actuating element 5, the
shutoff point 14 can be appropriately set or corrected directly
from at least one of the indicated start-up characteristic and the
voltage, and by an approximation of the temperature of the drive 3
or the correlated value of the shut-off point 14 so that
positioning in the set position 11 at rest can be obtained.
[0017] Additionally, at least one of the initial or average speed,
acceleration, and values of the drive 3 and the actuating element 5
derived from or corresponding to the aforementioned start-up
characteristic can be determined or acquired as a start-up
characteristic. Alternatively, at least one of the actual speed,
actual acceleration, and the values of the drive 3 and the
actuating element 5 which are derived therefrom or which correspond
thereto can be determined or acquired as a start-up characteristic.
In particular, in combination with the voltage applied to the drive
3, parameters arise for determining or estimating at least one of
the temperature of the drive 3 and of the slowing down or the
braking behavior of the drive 3. Current measurement or acquisition
of the voltage applied to the drive 3 can be omitted if it is
always constant; however, this is not always the case in a motor
vehicle. In addition, the power consumption of the drive 3 in the
start-up phase can be acquired as a start-up characteristic.
[0018] Preferably, each time the drive 3 is actuated a first
start-up characteristic is acquired as to how long the drive 3 or
the actuating element 5 should move by a predetermined angle of
rotation, or the angular displacement of the drive 3 or the
actuating element 5 moves within a predetermined time. This
acquisition can be determined via the sensor 8 which is made
preferably for position acquisition and which is provided in the
control means 9 which includes a corresponding clock base or time
base. Furthermore, the voltage applied to the drive 3 during the
start-up phase is acquired as the second start-up characteristic
via the control unit 9 since the control unit 9 supplies the drive
3 with voltage. Consequently, the two aforementioned start-up
characteristics can be determined without additional effort.
[0019] Using the two aforementioned start-up characteristics, the
temperature of the drive 3 can be determined or approximated by the
control means 9 via at least one of a function and a table filed in
the control unit 9. Subsequently, the expected slowing down or
braking angle 15 of the drive 3 is ascertained from the
temperature. Accordingly, the shut-off point 14 is established by
the control means 9 and may take place by a shut-off point 14 which
is stipulated as the base setting and a braking angle 15 which is
stipulated as the base setting being corrected or changed depending
upon the ascertained or acquired temperature. Of course, the
braking angle 15 and/or the shut-off point 14 can also be directly
determined from the two indicated start-up characteristics using at
least one of the function and a table filed in the control means 9.
It goes without saying that intermediate values can be interpolated
if necessary. In addition, the control means 9 can be made such
that, after shutoff and stopping of the drive 3, the actual
position of the drive 3 is compared to the respective set position
14 and correction of the corresponding function parameters or table
values is undertaken in order to adaptively enhance the positioning
accuracy. The present invention is advantageous since, at very
little cost, especially without an additional sensor means,
accurate positioning can be obtained for prompt stopping and
especially without control.
[0020] In accordance with the present invention, the actuating
element 5 executes rotary motion, while the actuating element 5 may
also execute linear or superimposed motion. In addition, the
present invention is not limited to a motor vehicle door lock 1,
but may also be applied to any electric motor positioning drive.
The present invention is, however, used especially in actuating and
drive systems in motor vehicles since economical and reliably
operating systems with a simple structure are desired.
* * * * *