Title of Invention

VEHICLE SENSOR FOR A BELT RETRACTOR HAVING A STAGGERED CONTACT SURFACE

Abstract

Self-locking belt retractor having a blocking system, for the belt winding shaft, that is controlled in an at least vehicle-sensitive manner, whereby the vehicle-sensitive sensor includes a sensor mass that via a bottom contact surface is disposed upright in a support part that has a planar bottom surface, whereby the sensor mass is disposed so as to be tiltable in the support part when vehicle accelerations occur, and via an actuator extension, for an associated sensor lever, extends through the bottom surface of the support part in an opening, characterized in that the contact surface (11) of the sensor mass (10) has a stepped or graduated configuration so as to form at least two tilt edges (16) whereby in the upright position of rest of the sensor mass (10), the step surfaces (15) that extend between the tilt edges (16), starting from the inner, central actuator extension (12) in an outward direction, are disposed at a respectively greater distance relative to the bottom surface (14) of the support part (13).

Full Text

VEHICLE SENSOR FOR A BELT RETRACTOR HAVING A STEPPED CONTACT SURFACE Description The invention relates to a self-locking belt retractor having a blocking system, for the belt-winding shaft, that is controlled in an at least vehicle-sensitive manner, whereby the vehicle-sensitive sensor includes a sensor mass that via a bottom contact surface is disposed upright in a support part that has a planar bottom surface, whereby the sensor mass is disposed so as to be tiltable in the support part when vehicle accelerations occur, and via an actuation extension, for an associated sensor lever, extends through the bottom surface of the support part in an opening. A self-locking belt retractor having the aforementioned features is described in DE 195 39 619 C2; to the extent that the upright sensor mass rests upon the bottom surface in the cup-shaped carrier part, the bottom contact surface of the sensor mass is formed with a slight curvature to improve the rollinq of the contact surface of the sensor mass upon the bottom surface of the carrier part if correspondingly occurring vehicle accelerations bring about a tilting of the sensor mass in the support part. The known belt retractor, i.e. the vehicle-sensitive sensor thereof, has the drawback that during the tilting movement of the sensor mass, the contact surface thereof and the bottom surface of the support part roll directly against one another, so that dirt particles that collect in the cup- shaped support part can obstruct the tilting movement as well as the resetting of the sensor mass, as a result of which the function of the vehicle-sensitive sensor, or its response or actuation precision with regard to its control movement for the sensor lever, can be adversely affected. For this reason, with the vehicle-sensitive sensor described in DE 42 09 272 A1 the sensor mass is placed upon elevations or protrusions formed on the bottom surface of a support part and provided with a rolling radius, as a result of which it is intended to effect a point-type support of the contact surface of the sensor mass, so that dirt particles will not obstruct the tilting movement. However, this has the drawback that the tilting characteristic of the sensor mass is a function of where the sensor mass is straight or erect. It is the object of the invention to improve the vehicle sensor of the belt retractor having the aforementioned features in such a way that the 2 Of 12 tilting characteristic of the sensor mass is not obstructed or altered even when dirt particles enter. The realization of this object, including advantageous embodiments and further developments of the invention, results from the content of the patent claims that follow this description. The basic concept of the invention is that the contact surface of the sensor mass has a stepped or graduated configuration so as to form at least two tilt edges, whereby in the upright position of rest of the sensor mass, the step surfaces that extend between the tilt edges, starting from the inner, central actuation extension in an outward direction, are disposed at a respectively greater distance relative to the bottom surface of the support part. The invention has the advantage that the contact surface of the support mass, and the bottom surface of the support part, no longer rest flat against one another, but rather roll via the tilt edges formed on the contact surface of the sensor mass, whereby dirt particles that might enter are received in the spaces formed by the steps between the respective step surface and the bottom surface of the support part, and thus the tilt movement of the sensor mass, and hence the function of 3 of 12 the vehicle-sensitive sensor, can no longer be adversely affected. An additional advantage is that the tilt characteristic of the sensor mass is independent of the position of the sensor mass in the support part, since in particular in contrast to the state of the art according to DE 42 09 272 A1, the tilt edges are disposed directly on the sensor mass. Pursuant to one exemplary embodiment of the invention, the step surfaces that extend between the tilt edges are oriented in a parallel arrangement relative to the bottom surface of the support part. A plurality of tilt edges having step surfaces between them can be disposed between the inner actuator extension and the outer peripheral edge of the contact surface of the sensor mass, whereby the outer peripheral edge of the contact surface expediently forms the outermost tilt edge. With regard to the arrangement of the tilt edges and configuration of the individual steps, it is provided pursuant to one exemplary embodiment of the invention that the spacings of the step surfaces relative to the bottom surfaces be configured such that each center of gravity angle (a) defined at a tilt edge is slightly less than the center of gravity angle (a) defined at the next closest inner tilt edge, whereby the 4 of 12 center of gravity angle (a) is the angle measured between the connecting line, which extends from the tilt edge to the center of gravity of the sensor mass, and the perpendicular line that at the tilt edge is directed toward the connection between the same tilt edge and the next closest inner tilt edge. Since the subsequent center of gravity angle, as viewed in the direction of the tilting movement, is respectively smaller than the previous center of gravity angle, when a corresponding vehicle acceleration occurs the sensor mass tilts completely. The drawing illustrates one exemplary embodiment of the invention, which is described subsequently. Shown is: Fig. 1 an overall, exploded view of a vehicle-sensitive sensor for a belt retractor, Fig. 2 the subject matter of Figure 1 in an assembled state, Fig. 3 a detailed, side view of the sensor mass of the vehicle sensor, Fig. 4 a partial view of the sensor mass of Figure 3 with angle sizes being indicated. 5 of 12 The vehicle sensor shown in Figures 1 and 2 comprises a support part 13 that, via a mounting pin 30, can be fixed in position on the housing of a non-illustrated belt retractor. Pivotably mounted on the support part 13 is a sensor lever 32. Formed in the support part 13 is a cup- shaped recess, on the bottom surface 14 of which is disposed, in an upright manner, a mushroom-shaped sensor mass 10 that, via an actuator extension 12, extends through the bottom surface 14 of the support part 13 in an associated opening 33. The sensor lever 32 is positively connected to the extension 12 of the sensor mass 10 that projects below the bottom surface 14; the sensor lever is pivotably mounted on the support part 13 in such a way that a tilting of the sensor mass 10, which is disposed on the bottom surface 14, out of the vertical axis leads to a deflection of the sensor lever 32. 31 designates an assembly aid for the vehicle sensor that facilitates the engagement of the vehicle sensor during assembly. The interaction of the previously described vehicle-sensitive sensor with the blocking system of the belt retractor is described in greater detail in the aforementioned DE 195 39 619 C2, so that reference is made thereto. As can be seen in detail from Figures 3 and 4, four tilt edges 16 are formed on the contact or support surface 11 of the sensor mass 10, which contact surface is to be supported on the bottom surface 14 of 6of 12 the support part 13, by forming the contact surface 11 in a stepped or graduated manner. For this purpose, starting from the inner, central actuator extension 12, three step surfaces 15 are formed that respectively extend parallel to the bottom surface 14 of the support part 13; in an outward direction, the step surfaces respectively have a greater spacing or distance relative to the bottom surface 14, so that the spacing of each tilt edge 16 formed thereby, relative to the bottom surface 14, is greater than the spacing of the next closest inner tilt edge 16 relative to the bottom surface 14. The outermost tilt edge 16 is, in this connection, formed by the outer peripheral edge of the contact surface 11. As can be seen from the left half of Figure 3, a rolling contour 17 results from an imaginary connection of the individual tilt edges 16 to one another, whereby between the rolling contour 17 and the respective step surface 15, a respective space 18 is formed for receiving dirt particles that might enter and that at this location do not obstruct the tilting movement of the sensor mass 10 on the bottom surface 14 of the support part 13. As can be seen in detail in Figure 4, the tilt edges 16 are disposed and configured on the contact surface 11 in such a way that individual center of gravity angles a0, ai, az, and 03 are formed, whereby each center of gravity angle a is the angle measured between the 7 of 12 connecting line 20, which extends from the tilt edge 16 to the center of gravity 19 of the sensor mass 10, and the perpendicular line 22 that in the pertaining tilt edge 16 is directed toward the connection 21 between the same tilt edge 16 and the next closest inner tilt edge 16. As can be seen from this illustration, the center of gravity angles ai, cfc, 03 that follow the center of gravity angle ao are respectively minimally smaller than the respective previous angle, thus ensuring a complete tilting of the sensor mass 10 during correspondingly greater vehicle acceleration. The height of the steps is selected such that the largest dirt particles that are to be received can find sufficient space. An altering or setting of the center of gravity angle can, if necessary, be undertaken in order to alter or respectively intentionally otherwise set the tilt characteristic of the sensor mass, whereby instead of the complete tilting of the sensor mass, it would also be possible to set a respective delayed complete tilting, or even a brief standstill of the sensor mass. To the extent that the sensor mass 10 tilts upon reaching the center of gravity angle a0l it is necessary, to achieve the tilting back of the sensor mass 10, to reduce the center of gravity angles a by the corresponding tilt angle (30, Pi, fc, or fo. By reducing the center of 8 of 12 I I gravity angle by the greatest tilt angle, the sensor mass 10 tilts completely back into the starting position. The features of the subject matter of these documents disclosed in the preceding description, the patent claims, the abstract and the drawing can be important not only individually but also in any desired combination with one another for realizing the various embodiments of ! the inventio Patent Claims 1. Self-locking belt retractor having a blocking system, for the belt winding shaft, that is controlled in an at least vehicle-sensitive manner, whereby the vehicle-sensitive sensor includes a sensor mass that via a bottom contact surface is disposed upright in a support part that has a planar bottom surface, whereby the sensor mass is disposed so as to be tiltable in the support part when vehicle accelerations occur, and via an actuator extension, for an associated sensor lever, extends through the bottom surface of the support part in an opening, characterized in that the contact surface (11) of the sensor mass (10) has a stepped or graduated configuration so as to form at least two tilt edges (16) whereby in the upright position of rest of the sensor mass (10), the step surfaces (15) that extend between the tilt edges (16), starting from the inner, central actuator extension (12) in an outward direction, are disposed at a respectively greater distance relative to the bottom surface (14) of the support part (13). 2. Belt retractor according to claim 1, characterized in that the step surfaces (15) that extend between the tilt edges (16) are oriented in a parallel arrangement (14) of the support part (13). 3. Belt retractor according to claim 1 or 2, characterized in that a plurality of tilt edges (16) having step surfaces (15) between them are disposed between the inner actuator extension (12) and the outer peripheral edge of the contact surface (11) of the sensor mass (10). 4. Belt retractor according to claim 3, characterized in that the outer peripheral edge of the contact surface (11) forms the outermost tilt edge (16). 5. Belt retractor according to one of the claims 1 to 4, characterized in that the spacings or distance of the step surfaces (15) relative to the bottom surface (14) are configured in such a way that each center of gravity angle (a) defined at a tilt edge (16) is slightly smaller than the center of gravity angle (a) defined on the next closest inner tilt edge (16), whereby the center of gravity angle (a) is the angle measured between the connecting line (20), which extends from the tilt edge (16) to the center of gravity (19) of the sensor mass (10), and the perpendicular line (22) that at the tilt edge (16) is directed toward the connection (21) between the same tilt edge (16) and the next closest inner tilt edge (16). 6. A belt retractor substantially as herein described with reference to the accompanying drawings.

Documents:

3171-CHENP-2004 EXAMINATION REPORT REPLY RECEIVED 27-09-2012.pdf

3171-CHENP-2004 FORM-3 27-09-2012.pdf

3171-CHENP-2004 OTHER PATENT DOCUMENT 27-09-2012.pdf

3171-CHENP-2004 POWER OF ATTORNEY 27-09-2012.pdf

3171-CHENP-2004 AMENDED PAGES OF SPECIFICATION 27-09-2012.pdf

3171-CHENP-2004 AMENDED CLAIMS 27-09-2012.pdf

3171-CHENP-2004 CORRESPONDENCE OTHERS 09-01-2012.pdf

3171-CHENP-2004 FORM-13 01-03-2013.pdf

3171-CHENP-2004 CORRESPONDENCE OTHERS 01-03-2013.pdf

3171-CHENP-2004 CORRESPONDENCE OTHERS 16-04-2012.pdf

3171-CHENP-2004 POWER OF ATTORNEY 01-03-2013.pdf

3171-chenp-2004 claims.pdf

3171-chenp-2004 correspondence others.pdf

3171-chenp-2004 correspondence po.pdf

3171-chenp-2004 description (complete).pdf

3171-chenp-2004 drawings.pdf

3171-chenp-2004 form 1.pdf

3171-chenp-2004 form 18.tif

3171-chenp-2004 form 3.pdf

3171-chenp-2004 form 5.tif

3171-chenp-2004 pct.pdf