Mechanical lever return system for the gearshift lever of a direction indicator switch in a motor vehicle

Description

[0001] The invention relates to a mechanical lever return system for the gearshift lever of a direction indicator switch in a motor vehicle, with an articulated plate coupled to the gearshift lever, which carries two locking pawls, each of which blocks a release cam coupled to the steering column in one direction and allows it to pass in the opposite direction, wherein the gearshift lever or a switching piece connected to the gearshift lever is coupled to a rotatably mounted driver via a rotary joint, wherein the articulated plate is floatingly mounted on the driver, and wherein the two locking pawls are each held in a basic position by a return spring, from which they can only be deflected in one direction of rotation upon deflection of the return spring.

[0002] A similar lever return system is already known from German patent DE 1 072 494 B. The locking pawls are each designed in three parts and each form a toggle lever. An overload protection device in the event of a return while the shift lever is held is not disclosed here.

[0003] From US patent specification US 5 021 617 A, a lever return system according to the preamble of claim 1 is known. In this system, a joint plate is mounted in a floating manner on a driver by means of an axially acting, spring-loaded locking cam.

[0004] Modern production steering column modules typically have a latching turn signal switch and a switching angle of approximately 10°-13°. Mechanical resetting of these standard switching paths can be easily achieved using today's standard turn signal reset systems.

[0005] Today's mass-produced return systems primarily operate via an inclined plane, over which a spring-loaded slide can be released linearly forward and retracted. Since the angle of this inclined plane cannot be made arbitrarily small, the system requires a sufficiently large switching angle.

[0006] At smaller switching angles, today's turn signal reset systems reach their functional limits. With future turn signal reset systems featuring particularly short switching travels planned, the question arose of an alternative reset system.

[0007] The task was to develop a mechanical lever return system that is suitable for short switching distances.

[0008] This object is achieved according to the invention in that the release cam is connected to a release ring which is rotatably mounted on a bearing ring coupled to the steering column against the force of a spring element.

[0009] The lever return system according to the invention does not require an inclined plane, but works with lever ratios and is therefore particularly suitable for short switching travels.

[0010] It can particularly advantageously use lever pivot axes that are not aligned parallel to the steering column, as is common today, and thus also compensate for a relatively large height offset between the lever pivot point and the release cam position.

[0011] An embodiment of the invention will be illustrated and explained below with reference to the drawings. They show, in a schematic diagram, the Figure 1: The top of a mechanical lever return system, Figure 2: The underside of a mechanical lever return system, Figure 3: The arrangement of various rotation axes, Figure 4: The coupling between a contact piece and a driver, Figure 5: The variable positioning of the release system relative to the contact piece and the release cam, Figure 6: A switching lever in its neutral position, Figure 7: The switching lever in the detent position, flashing to the left, Figure 8: An alternative version of the switching lever in the detent position, flashing to the left, Figure 9: The switching lever in an activated position, Figure 10: The switching lever in a release position, Figure 11: The switching lever and release cam in a first freewheeling position, Figure 12: The switching lever and release cam in a second freewheeling position, Figure 13: The release cam in a first overshifting position, Figure 14: The release cam in a second overshifting position, Figure 15: An enlarged view of the cam track during overshifting,Figure 16 shows a problematic switching position of the lever return system and the trigger ring. Figure 17 shows the underside of the mechanical lever return system with a trigger ring according to the invention. Figure 18 shows the arrangement of a spring element. Figure 19 shows the underside of the mechanical lever return system during initial contact. Figure 20 shows the underside of the mechanical lever return system with the trigger ring deflected. Figure 21 shows the underside of the mechanical lever return system during resetting. Figure 22 shows the underside of the mechanical lever return system in the zero position.

[0012] The Figures 1 and 2 schematically represent the top and bottom of a mechanical lever return system for the gear lever of a direction indicator switch in a motor vehicle.

[0013] The Figures 1 and 2show a switching element 1, which is coupled at a fastening section 21 to a shift lever (not shown here) of a steering column switch for indicating the direction of travel in a motor vehicle. The switching element 1 has a bearing bush 9, by means of which the switching element 1 is mounted on a fixed pivot axis (also not shown here). The switching element 1 thus follows pivoting movements of the shift lever about the pivot axis, with possible latching switching positions being predetermined in a known manner by a latching gate (not shown), on which a latching element connected to the shift lever or the switching element 1 is guided.

[0014] At its end section opposite the fastening section 21, the switching piece 1 is coupled by means of a rotary joint 20 to a driver 2, which is designed here as a flat plate. In a preferred embodiment, the rotary joint 20 is designed as a ball joint, as in the Figure 4is illustrated.

[0015] A joint plate 3 is arranged parallel to the driver 2, on which the driver 2 is mounted. For this purpose, as the Figure 2 shows a spring 11, which is supported at a bearing point 12 on the driver 2, the joint plate 3 against a cylindrical pin 10 attached to the driver 2. The pin 10 thus forms an axis of rotation for the floating joint plate 3. The spring 11 is designed here purely as an example as a helical spring.

[0016] The pin 10 engages in a cam track 13 incorporated in the joint plate 3. This allows the joint plate 3 to move laterally relative to the driver 2 in the event of higher forces acting against the force of the coil spring 11.

[0017] At two opposite sections of the joint plate 3, a locking pawl 4, 6 is pivotally mounted on a rotational axis 14, 15. Each locking pawl 4, 6 is preloaded relative to the joint plate 3 by means of a return spring 7, 8 designed as a leg spring. Due to the force of the return springs 7, 8, each locking pawl 4, 6 rests against a stop 24, 25 formed on the joint plate 3. Each locking pawl 4, 6 can therefore be pivoted about its associated rotational axis 14, 15 in exactly one pivoting direction against the force of the return spring 7, 8. A load on the locking pawls 4, 6 opposite to the pivoting direction presses the respective locking pawl 4, 6 against its associated stop 24, 25 on the joint plate 3, whereby the joint plate 3 is pivoted about the pin 10.

[0018] The locking pawls 4, 6 interact with one or more release cams 5, which are formed on a release ring 16 which is connected to the steering shaft or the steering wheel of a motor vehicle.

[0019] From the Figure 3 It is clear that the lever rotation axis 19 does not necessarily have to be arranged parallel to the rotation axis 10 formed by the pin 10 between the driver 2 and the joint plate 3 or to the rotation axis 28 of the release ring 16 and the steering column, but instead the position of the lever rotation axis 19 can be largely freely aligned in space.

[0020] For a free alignment of the contact piece 1, according to the Figure 4 The rotary joint 20 can be designed by a ball geometry 29 formed on the switching piece 1, which engages in a recess 30 on the driver 2. The movement of the ball or hemisphere 29 in the recess 30 as a linear guide compensates for spatial movements due to the non-parallelism of the lever rotation axis ( Figure 4 ).

[0021] The trigger system 32 (in the Figure 5 As a separate assembly, the contact piece (highlighted by a border) can be flexibly positioned in height relative to the contact piece 1 and the trigger cam 5. This allows for height differences between the lever pivot point and the trigger cam 5 to be compensated.

[0022] The following figures will explain the functionality of the mechanical lever return system in more detail.

[0023] In the Figure 6 The switching element 1 and the release cam 5 are shown in the zero position of the lever return system, which corresponds to the straight-ahead position of the steering wheel. The gear lever (not shown) or the connected switching element 1 is then moved to the left turn signal detent position (detent not shown). This actuates the driver 2 via the switching element 1 and moves the detent pawl 4 toward the release cam 5.

[0024] When the locking pawl 4 hits the release cam 5 ( Figure 7 ), it can rotate in the direction shown. The locking pawl 4 is now preloaded by the return spring 7.

[0025] As the Figure 8 As shown, the release cam 5, which is otherwise shown in one piece, can alternatively be divided into two small release cams 5a, 5b, so that the locking pawl 4 or 6 no longer has to be screwed in in most release cam / steering wheel positions.

[0026] If a turning maneuver, as in the Figure 9 As shown, if the release cam 5 is turned away from the area of ​​the locking pawl 4, the locking pawl 5 returns to its original position due to the preload of the return spring 7. This activates the release system.

[0027] If the release cam 5 is then turned back to the zero position for straight-ahead travel, the release cam 5 presses against the locking pawl 4 ( Figure 10). The locking pawl 4 transmits the force to the hinge plate 3, and via this in turn to the driver 2 and beyond to the switching piece 1, which ultimately pushes the switching lever out of its detent until it has returned to its neutral position. The same applies, of course, to the other functional direction, not shown here.

[0028] Since the release cam 5 can contact the locking pawl 4 from both sides, but only one direction serves to reset the switching lever, the locking pawl 4 must be able to deflect to one side. For this purpose, the locking pawl 4 is rotatably mounted on the hinge plate 3 and pre-tensioned by the return spring 7 ( Figure 11 ). If the release cam 5 hits the locking pawl 4 from the outside ( Figure 12), the locking pawl 4 rotates against the force of the return spring 7, creating a freewheel. Once the release cam 5 has passed the locking pawl 4, the locking pawl 4 returns to its original position via the return spring 7.

[0029] In the event that the shift lever is prevented from returning to the neutral position and the reset system is activated, a protective mechanism, also known as an over-shift system, prevents damage to the components. This protective mechanism ( Figure 13 ) is formed by the helical spring 11, the cam track 13, and the cylindrical pin 10. Advantageously, the pin 10 also serves as the bearing axis of the driver 2, thus enabling a space-saving design.

[0030] The preload by the coil spring 11 is selected to be large enough that, under the influence of dynamic effects, such as a high speed of the trigger cam 5 and a high inertia of the shift lever, the protective mechanism is not accidentally activated even though the shift lever is freely movable.

[0031] If the switching lever and thus the switching piece 1 are blocked and a sufficiently large force is introduced into the locking pawl 4 via the release cam 5 ( Figure 13 ), the protective mechanism starts working. The joint plate 3, which contains the cam track 13, moves with the cam track 13 along the cylindrical pin 10 and simultaneously rotates around the rear bearing point ( Figure 14 ).

[0032] The cam track 13 initially moves along the pin 10 with the steep flank 26 and then with the flat flank 27, which ensures that the force introduced via the release cam 5 is limited. Figure 15 illustrates the cam track 13 and the pin 10 guided therein in an enlarged illustration.

[0033] The movement of the joint plate 3 is a combined translational and rotational movement, which moves the locking pawl 4 out of engagement with the release cam 5. Once the locking pawl 4 is disengaged, the joint plate 3 automatically returns to its original position via the coil spring 11 and the cam track 13.

[0034] There is a problematic grey area when engaging the gearshift lever. Normally, as in the Figures 6 and 7As shown, when the turn signal lever is switched on, the locking pawl 4 or 6 moves in front of the release cam 5 and rotates in. If the steering wheel is turned through a sufficiently large angle of rotation and the release cam 5 is therefore no longer in front of one of the locking pawls 4, 6, the latter can plunge into the free space.

[0035] In a certain constellation of steering angle to indicator direction and simultaneous switching on of the indicator function, the kinematic movement of the respective locking pawl 4, 6 can lead to it hitting the side of the trigger cam 5. In the Figure 16In the steering angle position shown, this would be, for example, detent pawl 4. However, since detent pawl 4 cannot deflect in the direction of movement because it has the same direction of action as when resetting if release cam 5 is also rigid, the gearshift lever cannot be operated as usual. If an attempt were to engage the gearshift lever despite increased forces, the overshift system would be activated. The gearshift lever could be moved to the indicator position, but would generally not remain in the detent position due to the overshift system, but would be pushed back to the zero position. The indicator signal would be emitted. If one did not attempt to push the indicator lever further, depending on the steering angle position, no indicator signal could be emitted.

[0036] This problem only occurs in a specific, but very small, steering angle range (for example, between 23° - 28°), and only when the indicator is switched on in the same direction as the steering.

[0037] The solution to this problem is in the Figure 17 The release ring 16' with the release cam 5' is decoupled from the bearing ring 17 supporting the release ring 16' and is thus a separate component. The release ring 16' is mounted axially and radially on the bearing ring 17. The bearing ring 17 can, for example, be a component of a clock spring cassette.

[0038] The bearing is designed so that the release cam 5' can rotate both clockwise and counterclockwise against the bearing ring 17. This causes the release cam 5' to rotate when one of the locking pawls 4, 6 presses against the lateral surface of the release cam 5'. The possible rotation angle of the release cam 5' is so large that it does not interfere with the operation of the switching lever.

[0039] For this principle to work, the release cam 5' must be in the zero position at the beginning of a deflection. This means that the release ring 16' is centered on the bearing ring 17 in the zero position and can also be returned to the zero position from a deflected position.

[0040] This is achieved by a pre-tensioned spring element 18 between bearing ring 17 and release ring 16' ( Figure 18). The spring element 18 is designed here as a leg spring, which is held by its coiled section on a retaining pin 33 formed on the bearing ring 17, and whose legs rest on both sides on a spring bearing 31 also formed on the bearing ring 17. The spring element 18 can be deflected in both directions by a driving contour 34 connected to the release ring 16'.

[0041] The spring force of the spring element 18 holds the release cam 5' in the central position and also returns it to the zero position from a deflected position. This ensures that the release cam 5' can deflect both clockwise and counterclockwise.

[0042] In addition, the spring force of the spring element 18 presses the release ring 16' radially into a preferred position, so that the release ring 16' is mounted radially without play.

[0043] The Figures 19 to 22 illustrate how this arrangement works. Figure 19 shows the state of the initial contact between the latch 4 and the release cam 5'. The release cam 5' has not yet been moved.

[0044] Figure 20 shows a deflected release cam 5'. The spring element 18 is further tensioned by contact with the release ring 16'. The spring element 18 is strong enough to push the release cam 5' back to the neutral position against friction. On the other hand, the spring element 18 is designed to be as small as possible so that the release cam 5' does not push the switching lever out of the switch detent when the switch is switched on.

[0045] To disengage the gearshift lever via the mechanical return system, the release cam 5' is rotated until a driving geometry 22 of the release ring 16' comes into contact with a driving geometry 23 of the bearing ring 17. A force is then transmitted from the steering wheel via the bearing ring 17 and the release ring 16' to the locking pawl 4, which force is sufficiently large to push the gearshift lever out of the locking position ( Figure 21 ).

[0046] The Figure 22 shows the state after the reset process by the mechanical system. Reference symbol

[0047] 1Switching piece / universal joint 2Carrier 3Joint plate 4(first) locking pawl 5, 5', 5a, 5bTrigger cam 6(second) locking pawl 7(first) return spring 8(second) return spring 9Bearing bush (indicator rotation axis) 10Pin (driver rotation axis) 11Spring (coil spring) 12Bearing point 13Curved track 14Rotation axis (first locking pawl) 15Rotation axis (second locking pawl) 16, 16'Trigger ring 17Bearing ring 18Spring element 19Lever rotation axis 20Pivot joint 21Fastening section 22Drive geometry (of the trigger ring) 23Drive geometry (of the bearing ring) 24Stop 25Stop 26Steep flank 27Flat Flank 28Rotation axis (of the release ring) 29Spherical geometry (sphere or hemisphere) 30Recess 31Spring bearing 32Release system 33Retaining pin 34Drive contour

Claims

1. Mechanical lever-returning system for the switching lever of a turn signal switch in a motor vehicle, with a switching lever, with a driver (2) rotatably mounted on the axis of rotation (10), with a steering column, with a hinged plate (3) connected to the switching lever, which carries two latching pawls (4, 6) that each block a release cam (5, 5', 5a, 5b) connected to the steering column in one direction and allow it to pass in the opposite direction, wherein the switching lever or a switching piece (1) connected to the switching lever is coupled to the rotatably mounted driver (2) via a pivot joint (20), whereby the hinged plate (3) is mounted in a floating manner on the driver (2), and wherein the two latching pawls (4, 6) are each held by a return spring (7, 8) in a basic position, from which they can only be deflected in one direction of rotation, deflecting the return spring (7, 8), characterized in that the release cam (5, 5', 5a, 5b) is connected to a release ring (16, 16') which is mounted on a bearing ring (17) coupled to the steering column such that it can be rotated against the force of a spring element (18).

2. Mechanical lever-returning system according to claim 1, characterized in that the pivot joint (20) has a spherical geometry (29).

3. Mechanical lever-returning system according to claim 1, characterized in that the pivot joint (20) is a cardan joint.

4. Mechanical lever-returning system according to claim 1, characterized in that the latching pawls (4, 6) are each designed in one piece.

5. Mechanical lever-returning system according to claim 1, characterized in that the hinged plate (3) has a cam track (13), against which the axis of rotation (10) of the driver (2) rests in a spring-loaded manner.