Vehicle-sensitive sensor for a self-locking seatbelt retractor

Description

[0001] The present invention relates to a vehicle-sensitive sensor for a self-locking seatbelt retractor, comprising a carrier part, a sensor mass arranged standing on a contact surface of the carrier part and tiltable relative to the carrier part, and a locking lever coupled to the sensor mass and having an engagement point, wherein the locking lever has at least two rotational elements to form an axis of rotation for the locking lever and wherein each rotational element rests on a corresponding support point of the carrier part. The invention further relates to a self-locking seatbelt retractor with a vehicle-sensitive sensor.

[0002] A sensor with the aforementioned features is known, for example, from EP 3 459 797 B1. Such a sensor is used in a blocking system for a belt winding shaft of a self-locking belt retractor, wherein, in the event of triggering, the vehicle-sensitive sensor mass moves the locking lever with an engagement tip into engagement with a toothing of a control disc, so that the control disc is stopped in its common rotational movement with the belt winding shaft and the blocking system is thereby activated.

[0003] It has now been discovered that, despite known countermeasures, the locking lever detaches from its mounting, which allows rotational movement, in impact situations. Particularly at high temperatures, it has been observed that the locking lever detaches from its intended positions and / or its rotational movement is inhibited, thus compromising the activation of the locking system.

[0004] The object of the present invention is therefore to at least partially solve the disadvantages described with reference to the prior art and in particular to provide a vehicle-sensitive sensor whose robustness against malfunctions is increased.

[0005] One possible solution to this problem is provided by a vehicle-sensitive sensor with the features of independent claim 1. Possible further solutions and advantageous embodiments of the sensor are specified in the dependent claims and in the description, wherein individual features from the dependent claims and the description can be combined in a technically meaningful manner.

[0006] The vehicle-sensitive sensor includes, in particular, a carrier part, a sensor mass and a locking lever.

[0007] In its intended normal installed state, the sensor mass is arranged in a standing position on a base of the support part and can be tilted towards the support part.

[0008] The locking lever is coupled to the sensor mass, in particular by the locking lever passing through the sensor mass, which may be made in one part, two parts or more parts, wherein preferably a contact point between the section of the locking lever passing through the sensor mass and the sensor mass is realized by means of at least one raised section.

[0009] The locking lever also has an engagement point, which is located opposite the section that penetrates the sensor mass. The locking lever and, if applicable, the sensor mass can be designed, particularly in the contact area, such that the locking lever performs a rotational movement when the sensor mass tilts. In addition to the rotational movement, the axis of rotation defined by the rotational movement can also be linearly displaced.

[0010] To form an axis of rotation, the locking lever can have at least two, preferably exactly two, rotating elements. The rotating elements are formed, in particular, at two lateral ends of the locking lever.

[0011] In the intended normal state, the rotating elements each rest on a support point formed by the carrier part. Preferably, the rotating elements have a rounded outer circumference on their underside, over which the locking lever rolls from the support point during the rotational movement triggered by the tilting sensor mass.

[0012] In one embodiment, it is proposed that the support part has a recess for each rotating element and that the bottom of the recess forms the bearing surface for a rotating element. It is further proposed that the bottom of the recess be at least partially, preferably completely, covered by a ceiling of the respective recess, and thus, in the assembled normal state, the rotating element is also at least partially, preferably completely, covered by a ceiling of the respective recess. This ensures that even in impact situations, the rotating element does not lift off the bottom by an undefined distance. Rather, it ensures that, during a lifting movement from the bottom, the rotating element collides with the ceiling of the recess and thus remains in its intended position.

[0013] Preferably, exactly two recesses are formed on the lateral areas of the support part for the exactly two rotating elements of the locking lever. Each recess receiving a rotating element thus has a bottom and a top that covers this bottom, at least in the area of ​​the rotating element.

[0014] The recess may also have an opening through which the respective rotating element can be inserted / slid into the recess.

[0015] Such an opening is located, in particular, on a front side of the carrier part, i.e., on a side facing away from the contact surface and the sensor mass. Thus, during assembly, the locking lever can be inserted into the sensor mass with its corresponding section, and the rotating elements can be guided through the openings into the recesses.

[0016] To prevent the locking lever from falling out of the recess through the opening when the sensor is aligned in a certain way, the top of the recess can have a downward-projecting projection. This projection can be designed, in particular, so that the rotating element, which is not circular in cross-section, cannot be inserted into the recess through the opening in just any orientation.

[0017] Alternatively, the projection and the rotating element can be designed so that the locking lever with the rotating element can only be inserted into the recess through the opening with a certain amount of pressure, preventing the rotating element from simply falling out of the recess. During insertion, the projection / support part could, for example, deform elastically.

[0018] The projection can also have an additional or alternative function. For example, it can be designed and positioned to limit the (rotational) movement of the rotating element by ensuring that the rotating element comes into contact with the projection during its movement triggered by the sensor mass. In this way, the projection also defines a maximum deflection angle for the engagement tip of the locking lever.

[0019] To simplify the insertion of the locking lever into the support part, the opening may be designed to narrow towards the bottom of the recess. Thus, while the bottom of the recess is horizontally oriented in its normal, intended state, the opening slopes downwards from the end of the bottom towards the front.

[0020] In combination with a projection on the ceiling of the recess, a transition from the tapered opening to the bottom of the recess can be arranged behind the projection in the insertion direction of the rotating element. Particularly if the rotating element has a non-circular outer circumference, this allows the rotating element to be inserted into the recess through the opening in one mounting orientation and brought into its intended normal state by rotation within the recess. The projection prevents the rotating element from being dislodged from the recess by linear movement and can simultaneously limit the rotational movement of the locking lever.Furthermore, coupling with the sensor mass prevents the locking lever from returning to the mounting alignment position and thus prevents the rotating element from unintentionally coming out of the recess.

[0021] To further or alternatively limit the rotational movement of the locking lever, each recess can be assigned a forward-projecting stop element. The stop element is formed on the front face of the support element (and thus extends towards the engagement tip of the locking lever). In particular, this stop element is positioned offset inwards relative to the recess. The stop element can also be located directly below the tapered opening.

[0022] In this context, it can be provided that the locking lever preferably has downwardly projecting protrusions in an area between the rotating elements and the engagement tip, each of which is associated with a stop element. When the locking lever rotates due to the tilting movement of the sensor mass, the protrusion on the locking lever comes into contact with the stop element on the carrier part. The protrusions are arranged in a staggered pattern, extending inwards and towards the engagement tip, starting from the rotating elements located on the outside of the locking lever.

[0023] To create a non-circular outer circumference, the outer circumference of the rotating elements can be oval. Accordingly, in their intended normal orientation, the rotating elements exhibit convex curves on both the top and bottom surfaces, while the lateral edges in between are straight and vertical.

[0024] To facilitate rolling during the rotation of the locking lever, the rotating element can have a symmetrical (particularly semicircular) curvature on its underside. In a preferred embodiment, however, the rotating element can also have an asymmetrical curvature on its underside. In this case, the curvature, starting from the support point in the normal position, is different towards the front and thus in the direction of the rolling movement of the locking lever from the normal position, compared to the curvature towards the rear. Such a differential curvature can also be designed to allow the locking lever with the rotating elements to be inserted through the opening into the recess in the mounting orientation and pivoted there into the normal position, thereby securing the locking lever against unintentional dislodging.

[0025] The invention and its technical context are explained below using the figures as examples. They show schematic representations. Figure 1: A perspective view of a vehicle-sensitive sensor, Figure 2: An exploded view of the sensor, Figure 3: A side view of a sensor support part, Figure 4: A side view of a sensor locking lever, Figure 5: A side view of the sensor in a normal position, Figure 6: The side view with a rotated locking lever, Figure 7: A sectional view through the support part and the locking lever in the rotated state, Figure 8: A detail view of the Figure 7 Figure 9: a detailed side view of the sensor in the normal position and Figure 10: the detailed view according to Figure 9 with the locking lever rotated.

[0026] The vehicle-sensitive sensor shown in the figures comprises a carrier part 1, a sensor mass 2 and a locking lever 3.

[0027] The support part 1 comprises a base area 1.1 (see Figure 2 ), on which the sensor mass 2 rests and to which the sensor mass 2 is arranged to be tiltable.

[0028] The locking lever 3 comprises an engagement tip 3.1 and, on the side opposite the engagement tip 3.1, a section which, in the assembled state, is formed by the sensor mass 2 (see Figure 1 ) extends through it. At its lateral edges, the locking lever comprises 3 rotational elements 3.2a and 3.2b. In addition, on its underside, adjacent to the rotational elements 3.2a and 3.2b, the locking lever comprises protrusions 3.3a and 3.3b.

[0029] The support part 1 has recesses 1.3a and 1.3b in its lateral areas, each of which, with its base, forms a support point 1.2a and 1.2b for the rotating elements 3.2a and 3.2b of the locking lever 3. As can be seen in particular from the Figure 3As can be seen, the recess 1.3a, in addition to the base 1.3ai, has a cover 1.3a.ii that covers the base 1.3ai. The recess 1.3a also has an opening 1.3a.iii on its front side. The opening 1.3a.iii is designed such that it tapers from the front side towards the recess 1.3a. Furthermore, the recess 1.3a has a downwardly projecting projection 1.3a.iv on its cover 1.3a.ii.

[0030] Two stop elements 1.4a and 1.4b are also arranged on the front of the carrier part 1, which are offset inwards on the front with respect to the recesses 1.3a and 1.3b.

[0031] The opening 1.3a.iii and the projection 1.3a.iv are designed such that the associated rotational element 3.2a of the locking lever 3 can only be inserted into the recess 1.3 in a certain orientation. The locking lever 3 is then aligned so that it is in the Figure 5is in the depicted normal position. From Figure 5 It can also be seen that the locking lever 3 cannot be moved towards the front by a simple linear movement (in Figure 5 (i.e., to the right) out of the recess 1.3a, as it would bump into the projection 1.3a.iv.

[0032] The normal position is also in Figure 9 shown in detail. Here it can be seen that the bottom 1.3ai of the recess 1.3a is covered by the ceiling 1.3a.ii and that the projection 1.3a.iv extends downwards so far that it overlaps with the non-circular rotating element 3.2a.

[0033] In the Figure 6 and 10 The locking lever 3 is shown in a rotated position. It can be seen that the rotational element 3.2a comes into contact with the projection 1.3a.iv with its upper section, thereby limiting the rotational movement of the locking lever 3. In the Figures 9 and 10It can also be seen that the curvature of the rotation element 3.2a in its lower section, with which the rotation element 3.2a rests on the ground 1.3ai, is asymmetrical with respect to the point of contact.

[0034] From the in the Figures 7 and 8 The cross-sectional views shown also show that in the rotated position of the locking lever 3, the locking lever 3 with the protrusion 3.3b rests against the stop element 1.4b formed on the support part 1, which also limits the rotational movement of the locking lever 3. Reference symbol list

[0035] 1Support part 1.1Contact surface 1.2aSupport point 1.2bSupport point 1.3aRecess 1.3bRecess 1.3a.iFloor 1.3a.iiCeiling 1.3a.iiiOpening 1.3a.ivProjection 1.4aStop element 1.4bStop element 2Sensor mass 3Locking lever 3.1Intervention tip 3.2aRotation element 3.2bRotation element 3.3aProtuberance 3.3bProtuberance

Claims

1. Vehicle-sensitive sensor for a self-locking belt retractor, comprising - a support part (1), - a sensor mass (2) which is arranged vertically on a contact surface (1.1) of the support part (1) and can tilt relative to the support part (1) and - a locking lever (3) which is coupled to the sensor mass (2) and has an engagement tip (3.1), the locking lever (2) having at least two rotation elements (3.2a, 3.2b) for forming an axis of rotation for the locking lever (3), and each rotation element (3.2a, 3.2b) resting on an associated support point (1.2a, 1.2b) of the support part (4), characterized in that the support part (1) comprises a recess (1.3a, 1.3b) for each rotation element (3.2a, 3.2b), and a base (1.3a.i) of the recess (1.3a) forming a support point (1.2a), the base (1.3a.i) being covered by a cover (1.3a.ii) of the corresponding recess (1.3a).

2. Sensor according to claim 1, wherein each recess (1.3a, 1.3b) has an in particular front opening (1.3a.iii) by means of which a rotation element (3.2a) can be inserted into the recess (1.3a).

3. Sensor according to any of the preceding claims, wherein the cover (1.3a.ii) of the recess (1.3a) comprises a downwardly projecting projection (1.3a.iv) which limits a rotational movement of the rotation element (3.2a).

4. Sensor according to any of the preceding claims, wherein the opening (1.3a.iii) narrows towards the base (1.3a.i) of the recess (1.3a).

5. Sensor according to claim 4, wherein a transition from the tapering opening (1.3a.ii) to the base (1.3a.i) of the recess (1.3a) is located behind the projection (1.3a.iv) in an insertion direction of the rotation element (3.2a).

6. Sensor according to any of the preceding claims, wherein a forwardly projecting stop element (1.4a, 1.4b) is assigned to each recess (1.3a, 1.3b) and limits a rotational movement of the locking lever (3).

7. Sensor according to claim 6, wherein the locking lever (3) comprises protrusions (3.3a, 3.3b) in connecting portions between the rotation elements and the engagement tip (3.1), which protrusions are assigned to the stop elements (1.4a, 1.4b).

8. Sensor according to any of the preceding claims, wherein each rotation element (3.2a, 3.2b) has an asymmetric curvature on its underside starting from a minimum defined by a normal position.

9. Sensor according to any of the preceding claims, wherein the rotation elements (3.2a, 3.2b) are taller than they are deep and have an oval outer circumferential shape.

10. Belt retractor comprising a sensor according to any of the preceding claims.