Movable or removable closures – Safety means responsive to obstruction to closure – Sensing shoe on leading edge
Reexamination Certificate
1997-02-18
2001-05-01
McCall, Eric S. (Department: 2855)
Movable or removable closures
Safety means responsive to obstruction to closure
Sensing shoe on leading edge
C049S026000, C049S028000, C180S271000, C180S279000, C180S281000, C180S286000, C200S061410
Reexamination Certificate
active
06223467
ABSTRACT:
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention is directed to a motor vehicle sensor arrangement which is used to detect jamming, i.e., an obstruction, at a movable vehicle part which can be moved into an end position.
This application claims the priority of German Patent Application No. 44 29 325.9 filed on Aug. 18, 1994 and PCT Application No. PCT/EP95/03293 filed on Aug. 18, 1995, and German Patent Application No. 44 29 323.2 filed on Aug. 18, 1994 and PCT Application No. PCT/EP95/03292 filed on Aug. 18, 1995, the disclosures of which are expressly incorporated by reference herein.
Various sensors for detecting jamming are known. Frequently, information about a possible occurrence of jamming is collected from the performance data of an electric-motor drive unit for the movable vehicle part. The motor current or the torque delivered by the motor increases sharply when the movable vehicle part is jammed. These sensors may have problems, especially during prolonged operation, due to possible mechanical friction phenomena between the movable vehicle part and a typical mechanical guide which guides the movable vehicle part. Under these conditions, the sensors have difficulty distinguishing an actual case of jamming due to an obstruction from the normal operating state.
Mechanical transducers are also known that are incorporated in particular in a gasket against which the movable vehicle part presses in its end position. In such cases, for example, surfaces with a capacitive effect are placed against one another, and the distance between them changes if jamming occurs, i.e., if an object obstructs the movement of the movable vehicle part into its end position. The problem here is to distinguish between actual jamming by an obstructing object and the unobstructed entry of the door into its end position, when the same effect occurs. In the event of jamming, it is necessary to shut off an electric motor drive unit abruptly or even to reverse its direction of motion. If this were to be done, the movable vehicle part would always be stopped or reversed before reaching its final prescribed end position, which requires a partial deformation of the elastic gasket.
An object of the present invention is to provide a sensor device of the initially-described type which detects jamming reliably and dependably and which initiates the required emergency measures quickly and dependably only in such cases.
This and other goals have been achieved according to the present invention by providing a motor vehicle sensor arrangement for detecting jamming of an obstructing body at a movable vehicle part that is movable along a path into an end position, comprising: a pair of opposing walls spaced at a distance in an undeformed position to define a cavity therebetween, the cavity being located proximate but outside of the path of the movable vehicle part, at least one of the walls being formed of a resilient material, the distance between the walls being reduced when the obstructing body is engaged by the movable vehicle part; and a distance sensor arranged in the cavity and engageable with an interior portion of one of the walls to actuate a response signal, a distance between the distance sensor and the interior portion being less than the distance between the walls.
This and other goals have also been achieved according to the present invention by providing a motor vehicle sensor arrangement for detecting an obstruction at a movable vehicle part which is movable in a closing direction along a closing path into an end position, comprising: a resilient body arranged between a fixed vehicle structure and a resilient cover which is movable toward the fixed vehicle structure, one end of the cover being located proximate, but outside of, the closing path of the movable vehicle part, the one end of the cover being movable in the closing direction, the resilient body including a pair of opposing walls spaced at a first distance in an undeformed position to define a cavity therebetween; and a pressure transducer arranged in the cavity adjacent one of the walls, a projection arranged in the cavity on the other of the walls, the projection being aligned with and extending toward the pressure transducer, spaced by a second distance, much less than the first wherein an obstructing body which obstructs the closing path when the movable vehicle part is moved toward the end position is brought into contact with the one end of the cover, the movable vehicle part moving the obstructing body and the one end of the cover in the closing direction toward the fixed vehicle structure, the opposing walls being squeezed between the cover and the fixed vehicle structure, moving the pressure transducer into contact with the projection in order to actuate a response signal.
According to the present invention, the distance sensor/pressure transducer and its actuating mechanism are decoupled spatially. This allows a variety of different designs that make it possible to adapt the sensor device to various desired applications.
According to the present invention, the sensor arrangement is not located in the path of movement of the movable vehicle part, for example when the movable vehicle part is in its end position against a gasket. By mounting the sensor arrangement proximate, but outside, the path of movement of the movable vehicle part, the cavity is deformed only when an object obstructs the movement of the movable vehicle part toward its closed position. The deformation is caused by the action of the drive unit of the movable vehicle part on the jammed object. Normally the cavity remains in an undeformed position during the entire movement of the movable vehicle part into its end position, when no obstruction is encountered.
According to one preferred embodiment of the present invention, a projection is arranged in the cavity on one of the walls of the cavity, and extending toward the distance sensor/pressure transducer. As a result of the interaction between the distance sensor/pressure transducer and the projection of the cavity, the travel distance required for the pressure transducer to respond is advantageously reduced. By altering the size of the projection and/or the distance between opposite walls of the cavity, the travel distance between the distance sensor/pressure transducer and the projection can be adjusted in order to variably set the travel distance depending upon the application and the desired response characteristics. This travel distance can vary between zero (if the distance sensor/pressure transducer contacts the projection or the opposite wall) and the distance between the pressure transducer and the opposite wall (if no projection is provided on the opposite wall). In this way, it is also possible to compensate for mechanical tolerances. As a result of the interaction between the projection with the pressure transducer, the response characteristics of the pressure transducer, in other words the change of its output signal, can be adapted to the individual application conditions, depending upon the magnitude of the force to be detected and the triggering distance. The term “triggering distance” is the distance that the projection must travel for the critical signal change to occur in the pressure transducer.
The invention can be used at various locations in a motor vehicle. These include, for example, electrically operated windows, a sliding and tilting roof, a convertible top, or a door that is moved with servo support from a prelocked position into a locked position.
According to the present invention, a motor vehicle sensor arrangement is provided which can be simply installed, may be removed, and is simple to manufacture. Furthermore, the present invention significantly reduces the response travel of the distance sensor/pressure transducer. In addition, the present invention advantageously concentrates movement in the distance sensor/pressure transducer area. Finally, the present invention advantageously reduces the response distance between the distance sensor/pressure transducer and t
Mahalek Josef
Serban Bogdan
Witte Michel
Bayerische Motoren Werke Aktiengesellschaft
Evenson, McKeown, Edwards & Lenahan P.L.L.C.
McCall Eric S.
LandOfFree
Motor vehicle sensor arrangement for detecting jamming does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Motor vehicle sensor arrangement for detecting jamming, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Motor vehicle sensor arrangement for detecting jamming will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2543681