Coupling device, in particular for a belt retractor and belt retractors with coupling devices

Abstract

Coupling device (10) which can be arranged between a first and a second device (6, 8) and which couples the first and second devices (6, 8) in an engaged state and does not couple them in an uncoupled state, wherein the coupling device (10) has at least one coupling element which, in a coupling position, switches the coupling device (10) into the engaged state and, in a disengaging position, switches the coupling device (10) into the disengaged state and wherein the coupling element, upon commissioning of the second device (8), transitions from the decoupling position to the coupling position due to inertia, wherein the coupling element is a pivotable element (11) which is mounted on a pivot axis (12), characterized by the fact that - a support unit (13) comprises a first support element (13a) and a second support element (13b), wherein both support elements (13a; 13b) are pivotably connected to each other via the pivot axis (12) arranged on the second support element (13b), - the first support element (13a) is tiltably connected to the second device (8) at an end face (S) and is immediately set into a tilting movement by the second device (8) upon commissioning, wherein the tiltable connection of the first support element (13a) to the second device (8) at the end face (S) is effected via a toothed connection, and - the second support element (13b) has an axis of rotation which is arranged coaxially with the axis of rotation (14) of the first and / or the second device (6, 8) and the pivot axis (12) is arranged radially offset from this axis of rotation (14).

Description

[0001] The invention relates to coupling devices, in particular for belt retractors, as well as to belt retractors equipped with coupling devices.

[0002] European patent EP 1 981 739 B1 discloses a coupling device that can be arranged between a first and a second device and can couple the first and second devices in an engaged state and decouple them in a disengaged state. The coupling device has a coupling element that, in a coupled position, switches the coupling device to the engaged state and, in a disengaged position, switches the coupling device to the disengaged state. When the second device is engaged, the coupling element undergoes a translational movement due to inertia, thereby transitioning from the disengaged to the coupled position.

[0003] Further coupling devices are known from the publications or patent specifications DE 10 2008 028 698 A1, DE 699 14 842 T2, DE 603 ​​10 818 T2 and EP 1 981 739 B1.

[0004] A coupling device with the features according to the preamble of claim 1 is disclosed in German patent application DE 10 2014 009 038 A1.

[0005] The invention is based on the objective of providing a coupling device with improved coupling behavior.

[0006] This problem is solved according to the invention by a coupling device having the features according to claim 1. Advantageous embodiments of the coupling device according to the invention are specified in the dependent claims.

[0007] A significant advantage of the coupling device according to the invention is that, due to the arrangement of the pivoting element around the pivot axis, the pivoting element responds and the coupling device engages only when the second device, for example a coupling or planetary gear, is set into rotation by a drive element directly or indirectly, and only then does the coupling element pivot or tilt.

[0008] Unlike previously known coupling devices, such as the one described in the aforementioned patent EP 1 981 739 B1, the coupling device cannot engage if it is only accelerated translationally (or linearly), for example, forwards or backwards when arranged in a vehicle.

[0009] The second device must therefore be set into a rotational movement so that, due to the physical inertia of the coupling device and / or a change in the position of the swiveling element, the latter initially remains stationary or lags behind the second device. Only after a time delay does the swiveling element follow the rotational movement and subsequently rotate. The decisive factor is the change in the position of the swiveling element, which causes it to engage with a counter-element, for example, the external teeth of a belt spool, thereby coupling them. This creates a positive-locking coupling for power transmission, originating from the second device or a drive element acting upon it, via the coupling device with the swiveling element, and ultimately to a connected component.The engagement pinion, which has a corresponding engagement structure - for example in the form of external teeth - for the swiveling element and drives, for example, a belt spool.

[0010] One advantage of this positive-locking coupling is that, for example, if decoupling of the coupling pairs is required—e.g., in a vehicle accident—it can be achieved easily and exceptionally simply by rotating the first component or pinion at a higher angular velocity / rotational speed than the second component. This disengages the pivoting element from the power transmission, ensuring free movement. In other words, the pivoting element is ejected from the engagement and thus decouples itself. Power transmission therefore occurs in only one direction.

[0011] By means of the two bearing points or the three pivot points of the support unit, namely at the front face with the tiltable connection, at the axis of the two support elements and at a pivot axis on one of the two support elements, in particular on the second support element, the support unit can also perform a tilting or buckling movement when the second device is controlled and thereby advantageously support the pivotable element during its pivoting movement for coupling.

[0012] If improved functionality of the inertial coupling position requires it, the bearing friction can be made adjustable to ensure that the coupling mechanism lags behind the second mechanism during acceleration, thus optimizing the coupling mechanism. Specifically, this could be achieved through adjustable or different fits of the bearing pairs, and / or by modifying the surface structure of the bearing raceways with appropriate lubricants.

[0013] In an advantageous embodiment of the invention, the tiltable connection between the second device and the support unit or support element is an involute gear toothing.

[0014] Other connections are also conceivable which allow the carrier unit to be slightly displaced, twisted or tilted relative to the second device due to the common coaxial arrangement with the axis of rotation on one side and a movable connection, in particular a linearly movable connection, with the second device on the other side.

[0015] A twisting, shifting or tilting would occur particularly at the front face around a pivot point or a path length, which, in a side view, extends circumferentially along the second device.

[0016] The twisting or tilting should be minimal enough to overcome a distance sufficient to engage the pivoting element in the coupling position. This depends, among other things, on the engagement depth of a coupling partner, for example, the tooth height in the case of external gearing.

[0017] Furthermore, it can be advantageous if the shape of the carrier unit or carrier elements is designed such that its center of gravity, either alone or together with the coupling element mounted on it, corresponds to the axis of rotation. This ensures smooth, low-vibration operation of the coupling device even at high speeds.

[0018] The invention further relates to a belt retractor equipped with a coupling device as described above.

[0019] A belt spool of the belt retractor preferably forms the first device mentioned above or is directly connected to it, and a winding device of the belt retractor preferably forms the second device mentioned above. The winding device is preferably an electric or electronic winding device.

[0020] The axis of rotation and the belt spool axis are preferably arranged coaxially or on the same axis.

[0021] When the winding device is put into operation, the pivot axis is set into a circular rotational movement around the belt spool axis.

[0022] The pivotable element preferably has a first and a second end section that are located on different sides of the pivot axis.

[0023] The end sections are preferably deflected differently in the belt winding direction when the winding device is put into operation, namely preferably in such a way that the first end section - viewed from the axis of rotation of the support element - pivots radially outwards and the second end section - viewed from the axis of rotation of the support element - pivots radially inwards.

[0024] The pivotable element, in particular its second end section, preferably engages in the coupled position with an external toothing of a belt spool wheel that is connected to or integrally formed with the belt spool. Alternatively or additionally, the pivotable element, in particular its first end section, can engage in the coupled position with an internal toothing of another belt spool wheel that is connected to or integrally formed with the belt spool.

[0025] There may also be one or more intermediate gear wheels with internal and / or external teeth, into which the swiveling element engages or engages.

[0026] The first end section preferably has a toothed structure radially outward, viewed from the axis of rotation of the support element. Alternatively or additionally, the second end section may have a toothed structure radially inward, viewed from the axis of rotation of the coupling wheel.

[0027] The winding device is preferably reversible. It is preferably formed by an electric motor or preferably includes one.

[0028] It is also advantageous if the belt retractor has an emergency tensioning device, preferably formed by or comprising a pyrotechnic drive, in particular a pyrotechnic ball tensioner drive.

[0029] The invention is explained in more detail below with reference to exemplary embodiments; these show, by way of example, Fig. 1 An embodiment of a coupling device according to the invention in perspective view; Fig. 2 the coupling device according to Fig. 1 in perspective view and in a coupled state; Fig. 3 a perspective section of a tiltable connection; Fig. 4 the coupling device according to Fig. 1 in disengaged state and in a side view; and Fig. 5 the coupling device according to Fig. 4 in a clutched state and in a side view.

[0030] For the sake of clarity, the same reference symbols are always used in the figures for identical or comparable components.

[0031] The Fig. 1 and Fig. Figure 2 each shows a coupling device according to the invention in perspective view. Fig. 1 the coupling device 10 is in a decoupling position, wherein a coupling element in the form of a pivotable element 11 is not positively connected to a first device 6, for example in the form of a belt spool or a pinion on which the belt spool is directly arranged.

[0032] In Fig. In contrast, in position 2 the pivotable element 11 is in a coupled position, wherein the pivotable element 11 is positively connected to the first device 6. Thus, a torque or force originating from the second device 8, for example in the form of a coupling wheel, planetary gear or pinion, can be transmitted to the first device 6.

[0033] To achieve this, the coupling device 10 comprises a support unit 13, which has a rotational axis that is arranged coaxially with the first and second devices 6; 8. The common axis of these components is thus the rotational axis 14 (shown in Fig. 4) Furthermore, the support unit 13 has a pivot axis 12 that pivotably connects the pivotable element 11 to the support unit 13. The pivot axis 12 runs parallel to the axis of rotation 14.

[0034] The Fig. Figure 3 shows a perspective view of an enlarged section of a tiltable connection between the support unit 13 and the second device 8, thereby initiating the coupling position. Accordingly, the tiltable connection is arranged on an end face S of the support unit 13 or the second device 8 and is connected to the second device 8 by means of a toothed connection. The two toothed connections form a pair of teeth, with the toothed connection of the second device 8 having two teeth and the toothed connection of the support unit 13 having three teeth.

[0035] To advantageously execute the tilting movement of the support unit 13, which initiates the pivoting movement of the pivotable element 11, the support unit 13 is divided into at least two parts. In this at least two-part embodiment of the support unit 13, it comprises a first support element 13a and a second support element 13b. Both support elements 13a and 13b are pivotably connected to each other via the pivot axis 12. The support unit 13 thus has two pivot points – on the axis of rotation 14 and the pivot axis 12 – and a floating bearing in the form of the toothed connection on the end face S.

[0036] The toothing thus enables the carrier unit 13 to perform a tilting, pivoting, or rotational movement around its axis of rotation 14, as a slight change in position relative to the second device 8 is permitted. The toothing amplifies or initiates the change in position when the engagement angle of the tooth pair changes.

[0037] Bearing friction between the bearing points of the carrier unit 13 and its axis of rotation 14, and between the pivoting element 11 and its pivot axis 12, also influences the inertial behavior of the coupling device 10. The bearing friction can therefore be adjusted, or be adjustable, depending on the desired coupling behavior, i.e., whether the bearing friction should be low or high.

[0038] In any case, it is desirable for the carrier unit 13 to lag behind the accelerated second unit 8. Alternatively, this can also be achieved by a deceleration behavior of the carrier unit 13 by means of bearing friction or a separate deceleration device.

[0039] If the second device 8 is now subjected to an angular momentum, only the second device 8 rotates. The support unit 13 with the associated pivotable element 11 initially remains in place due to its physical inertia; it therefore does not initially follow the rotation of the second device 8.

[0040] The carrier unit 13 is also tilted relative to an axis of the second device 8 due to the changed engagement angle of the tooth pair. This change in position is, for example, in the area of ​​the front face S of the carrier element 13a in the Fig. 3, Fig. 4 and Fig. 5 clearly visible. Due to this tilting, the pivoting element 11 rotates – compared to the initial position – and engages with the external toothing 6b, in this case a sawtooth toothing, of the first device 6. The coupling pair is positively coupled and rotates together. This allows forces to be transferred at least in one direction of rotation – in the case of the Fig. 1, Fig. 2, Fig. 3, Fig. 4 to Fig. 5 counterclockwise - to be transferred.

[0041] If decoupling becomes necessary later, for example because a pyrotechnic drive is at least indirectly connected to the first device 6 and is to be triggered, this is achieved by the different angular velocities of the first and second devices 6; 8. As soon as the first device 6 has a higher angular velocity than the second device 8, the pivoting element 11 disengages from the external gearing 6b. This results in the coupling device 10 being decoupled. Reference symbol list 6 first establishment 6b External gearing 8 second facility 10 Coupling device 11 swiveling element 11a first end section 11b second final section 12 swivel axes 13 Carrier unit 13a first support element 13b second support element 14 Rotation axis S Front

Claims

[1] Coupling device (10) which can be arranged between a first and a second device (6, 8) and which couples the first and second devices (6, 8) in an engaged state and does not couple them in an uncoupled state, wherein the coupling device (10) has at least one coupling element which, in a coupling position, switches the coupling device (10) into the engaged state and, in a disengaging position, switches the coupling device (10) into the disengaged state and wherein the coupling element, upon commissioning of the second device (8), transitions from the decoupling position to the coupling position due to inertia, wherein the coupling element is a pivotable element (11) which is mounted on a pivot axis (12), characterized by , that - a support unit (13) comprises a first support element (13a) and a second support element (13b), wherein both support elements (13a; 13b) are pivotably connected to each other via the pivot axis (12) arranged on the second support element (13b), - the first support element (13a) is tiltably connected to the second device (8) at an end face (S) and is immediately set into a tilting movement by the second device (8) upon commissioning, wherein the tiltable connection of the first support element (13a) to the second device (8) at the end face (S) is effected via a toothed connection, and - the second support element (13b) has an axis of rotation which is arranged coaxially with the axis of rotation (14) of the first and / or the second device (6, 8) and the pivot axis (12) is arranged radially offset from this axis of rotation (14). [2] Coupling device (10) according to claim 1, characterized by, that the connection of the carrier unit (13) or the first carrier element (13a) with the second device (8) at the end face (S) is made via a toothing, in particular an involute toothing. [3] Coupling device (10) according to claim 1 or 2, characterized by , that a bearing friction of the axis of rotation with the axis of rotation (14) and / or a bearing friction of the pivot axis (12) with the pivotable element (11) is adjusted such that the inertia-induced coupling position is optimized. [4] Coupling device (10) according to any one of claims 1 to 3, characterized by , that a shape of the second support element (13b) is designed such that the center of gravity of the second support element (13b) lies on the axis of rotation or the axis of rotation (14). [5] Seatbelt retractor, characterized by , that this is equipped with a coupling device (10) according to one of the preceding claims, wherein a belt spool of the belt rewinder forms the first device (6) or is directly connected to it and wherein a winding device, in particular an electronic winding device, forms the second device (8) or is directly connected to it. [6] Belt retractor according to claim 5, characterized by , that the axis of rotation (14) and the belt spool axis are arranged coaxially and the pivot axis (12) is set into a circular rotational movement around the belt spool axis when the winding device is put into operation. [7] Belt retractor according to one of claims 5 to 6, characterized by, that the pivotable element (11) has a first and a second end section (11a, 11b) which are located on different sides of the pivot axis (12), and the end sections are deflected differently in the belt winding direction when the winding device is put into operation, namely such that the first end section (11a) - seen from the axis of rotation (14) - pivots radially outwards and the second end section (11b) - seen from the axis of rotation (14) - pivots radially inwards. [8] Belt retractor according to claim 7, characterized by, that the pivotable element (11), in particular its second end section (11b), engages in the coupled position in an external toothing (6b) of a belt spool wheel (6) connected to or formed on the belt spool, and / or the pivotable element (11), in particular its first end section (11a), engages in the coupled position in an internal toothing of a belt spool wheel (6) connected to or formed on the belt spool. [9] Belt retractor according to claim 7 or 8, characterized by , that the first end section (11a) - viewed from the axis of rotation (14) - has a tooth structure radially outside and / or the second end section (11b) - viewed from the axis of rotation (14) - has a tooth structure radially inside. [10] Belt retractor according to any one of claims 5 to 9, characterized bythat the winding device is a reversibly operating winding device formed by or comprising an electric motor, and / or that an emergency tensioning device is present, formed by or comprising a pyrotechnic drive, in particular a pyrotechnic tensioning drive.

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