The invention relates to a sensor, in particular for triggering a vehicle occupant restraint system, for example for triggering a locking mechanism of a belt retractor.
A sensor of this type is known, for example, from German laid-open application DE 10 2004 032 190 A1. This previously known sensor has a lower rolling surface which is defined by a track which runs in a curved manner, extends convexly with respect to the inertia body and is designed without a step. The inertia body can execute a translatory rolling movement on the lower rolling surface.
The invention is based on the object of specifying a sensor in which production of noise is avoided or is at least kept as small as possible.
This object is achieved according to the invention by a sensor with the features according to patent claim 1. Advantageous refinements of the sensor according to the invention are specified in dependent claims.
Accordingly, the invention provides a sensor with an inertia body which has an oscillating bearing permitting an oscillating movement and, in the event of an acceleration, can be set by inertia into an oscillating movement, and a triggering lever which interacts with the inertia body and is deflected when a predetermined amplitude of oscillation is exceeded.
A substantial advantage of the sensor according to the invention is considered that of avoiding annoying rolling noises therein. This is because, in contrast to the previously known sensor described at the beginning, the sensor according to the invention uses an oscillating movement rather than a rolling movement. Rolling noises are therefore avoided.
It is considered advantageous if the sensor has a holding element, wherein a first section of the holding element is guided through the oscillating bearing of the inertia body and holds the inertia body pivotably, and a second section of the holding element is guided through a pivot bearing of the triggering lever and holds the triggering lever pivotably. In this refinement, an independent and self-supporting oscillating unit which comprises the holding element, the inertia body and the triggering lever is formed by a single additional component, namely the holding element.
The first and the second sections preferably extend parallel, and therefore the pivot axes of the inertia body and those of the triggering lever are preferably also parallel.
The first section is preferably designed in such a manner that the inertia body can be pivoted out in all directions. For this purpose, the oscillating bearing of the inertia body and/or that section of the inertia body which is indirectly or directly adjacent to the oscillating bearing can have, for example, conically converging side walls.
Particularly preferably, the holding element has a third section which enables fitting of the oscillating unit formed by the holding element, the inertia body and the triggering lever, in particular to or in a housing or to an external vehicle-side support.
The third section of the holding element preferably extends perpendicularly to the first and/or to the second section of the holding element.
With regard to a high degree of stability and low degree of friction in the oscillating bearing of the inertia body and in the pivot bearing of the triggering lever, it is considered advantageous if the holding element is formed by a multiply bent, single-part rod element, and the first, second and third sections of the holding element are sections of said single-part rod element. The rod element can be formed by a multiply bent, single-part metal wire, preferably made of spring steel. Alternatively, the rod element can be composed of plastic or of a metal and plastic composition, i.e. partially of plastic and partially of metal.
The same applies to the oscillating bearing of the inertia body and the pivot bearing of the triggering lever: said bearings are also preferably composed of metal, plastic or a metal and plastic composition.
If the sensor has a frame or a housing, it is considered advantageous if the third section of the holding element is hooked into the frame or the housing of the sensor and thereby fixes the position of the oscillating unit formed by the holding element, the inertia body and the triggering lever relative to the frame or relative to the housing.
It is also considered advantageous if the inertia body has an upper oscillating section and a lower oscillating section, wherein the upper and the lower oscillating sections are separated from each other by the oscillating bearing. The lower oscillating section is preferably composed of metal, for example iron.
The end section of the upper oscillating section may be, for example, plate-shaped or in the shape of a point. In the case of a plate-shaped configuration, a flat, round or conical plate shape is considered advantageous.
The shape of the triggering lever is preferably matched to the shape of the upper oscillating section. If the upper oscillating section is in the shape of a point, a dish-shaped triggering lever is considered advantageous, wherein the point of the upper oscillating section is preferably guided in a dish section of the dish-shaped triggering lever.
If the end section of the upper oscillating section is plate-shaped, a triggering lever with a cup-shaped section is considered advantageous, wherein the plate-shaped end section of the upper oscillating section is preferably guided in the cup-shaped section of the triggering lever.
Furthermore, it is considered advantageous if the mass of the upper oscillating section is smaller than the mass of the lower oscillating section. The mass of the lower oscillating section is preferably at least ten times larger than that of the upper oscillating section.
The arrangement of the oscillating bearing, the lever length of the upper and lower oscillating sections and the respective mass of the upper and lower oscillating sections determine the oscillating behavior of the inertia body and the sensitivity of the sensor. The parameters mentioned can be adapted to one another depending on the desired sensitivity of the sensor.
In order to avoid unnecessary triggering of the sensor in the event of small vehicle accelerations, it is considered advantageous if the triggering lever has a supporting section which, in the oscillation-free rest position of the inertia body, rests on the upper oscillating section and, by means of gravitational force, opposes an oscillating movement of the inertia body. In this refinement, the supporting section can be caused by gravitational force to press with the mass thereof against the upper oscillating section and can avoid oscillating in the event of only small vehicle accelerations.
Alternatively, it is considered advantageous if the triggering lever has an interaction section which, in the oscillation-free rest position of the inertia body, is spaced apart from the upper oscillating section and is brought into contact with the upper oscillating section only in the event of an oscillating movement, the amplitude of which exceeds a predetermined threshold.
It is also considered advantageous if the oscillating bearing is formed by a ball and socket joint, since ball and socket joints enable deflection of the inertia body and oscillation in all directions.
The invention also relates to an arrangement with a sensor, as described above, and with a vehicle, wherein the holding element is hooked into a vehicle-side support.
The invention furthermore relates to a belt retractor with a locking mechanism which is provided with a sensor of the described type. With regard to the advantages of the belt retractor according to the invention, reference is made to the abovementioned advantages of the sensor according to the invention. The belt retractor will produce less noise than previously known belt retractors, since the sensor contained therein operates quietly.
The invention is explained in more detail below with reference to exemplary embodiments, in which, by way of example
For the sake of clarity, the same reference numbers are always used for identical or comparable components in the figures.
It can be seen in
A second section 32 of the holding element 30 is guided through a pivot bearing of a triggering lever 40 where it forms a second shaft, namely a pivot shaft for the triggering lever 40. The triggering lever 40 can pivot about said second shaft. The pivot bearing of the triggering lever 40 is identified in
The inertia body 20 and the triggering lever 40 are connected to each other by the holding element 30, and therefore an independent and self-supporting oscillating unit 50 is formed by the three components, namely the inertia body 20, the holding element 30 and the triggering lever 40.
It can also be seen in
The first section 31 of the holding element 30 is preferably arranged in such a manner that the inertia body 20 can execute an oscillating movement in the longitudinal direction of the vehicle. An oscillating movement in the longitudinal direction of the vehicle is identified by a double arrow and the reference symbol P in
It can furthermore be seen in
In the illustration according to
The effect achieved on account of the dead weight of the triggering lever 40 and on account of the supporting section 42 of the triggering lever 40 pressing onto the upper supporting surface 25 of the inertia body 20 is that an oscillating movement of the inertia body 20 is suppressed, or at least made difficult, at smaller changes in acceleration of the vehicle. An undesirable production of noise is therefore prevented in the event of only small changes in acceleration of the vehicle. If, by contrast, a pronounced change in the acceleration or a jerky movement of the vehicle occurs, the triggering lever 40 will no longer be able to prevent the inertia body 20 from oscillating, and therefore the triggering lever 40 will be deflected and the locking section 43 will engage in the locking base 60.
In addition, a silent position of the inertia body 20 can also be brought about by a form fit, as shown by way of example in
Furthermore, a third section 33 of the holding element 30 can be seen in
The third section of the holding element 30 is preferably oriented perpendicularly to the first section 31 and perpendicularly to the second section 32 of the holding element 30 in order to achieve as compact a construction of the sensor 10 as possible.
Furthermore, it can be seen in
If, on account of an abrupt change in the acceleration of the vehicle, an oscillating movement of the inertia body 20 then occurs, at a sufficient amplitude of the oscillating movement the upper supporting surface 25 of the inertia body 20 will strike against the interaction section 45 of the triggering lever 40 and pivot the triggering lever upward in the arrow direction P2 such that the locking section 43 of the triggering lever 40 can engage in the locking base 60.
It is furthermore seen in
If, in the event of a change in the acceleration of the vehicle, an oscillating movement of the inertia body 20 occurs, the resultant oscillating movement of the plate-shaped end section 24 will lead to a deflection of the triggering lever 40 such that a locking section 43 of the triggering lever 40 can engage in a locking base 60.
It can be seen in
10 sensor
20 inertia body
21 lower oscillating section
22 upper oscillating section
23 oscillating bearing
23
a side walls
24 end section
25 supporting surface
28 spherical section
30 holding element
31 first section
32 second section
33 third section
40 triggering lever
41 pivot bearing
42 supporting section
43 locking section
45 interaction section
48 dish section
49 cup-shaped section
50 oscillating unit
60 locking base
70 housing
90 stop
100 bearing
110 ball and socket joint
120 point
a distance
P oscillating movement
P1 pivoting direction
P2 arrow direction
Number | Date | Country | Kind |
---|---|---|---|
102010063903.6 | Dec 2010 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/DE2011/050054 | 12/7/2011 | WO | 00 | 5/24/2013 |