Abstract
A safety device for a motor vehicle, which has a striker, a pawl, an ejection spring ejecting the striker, and a rotary latch, wherein the rotary latch has an opening direction of rotation, a closing direction of rotation an open position, and a main locking position, wherein the ejection spring has a leg and the leg lies directly against the striker in the main locking position of the rotary latch and the leg lies directly against the rotary latch in at least one intermediate position of the rotary latch, in which the rotary latch is between the main locking position and the open position.
Claims
1. A safety device for a motor vehicle, comprising: a striker, a pawl, an ejection spring for ejecting the striker, and a rotary latch, wherein the rotary latch has an opening direction of rotation, a closing direction of rotation, an open position, and a main locking position, and wherein the ejection spring has a leg and the leg lies directly against the striker in the main locking position of the rotary latch and the leg lies directly against the rotary latch in at least one intermediate position of the rotary latch, in which the rotary latch is between the main locking position and the open position, wherein the ejection spring is formed as a spiral spring, and wherein the rotary latch and the ejection spring are accommodated on a common pivot axis.
2. The safety device according to claim 1, wherein the rotary latch has a pre-locking position and the leg lies directly adjacent on the rotary latch in the pre-locking position.
3. The safety device according to claim 1, wherein the leg lies adjacent alternately on the striker and the rotary latch during rotation of the rotary latch in the opening direction of rotation.
4. The safety device according to claim 1, wherein the leg is formed in such a way that during adjacency change of the leg from the striker to the rotary latch traction is provided for between the leg and the striker.
5. The safety device according to claim 1, wherein the ejection spring has a pivot axis and the leg in a first plane vertical to the pivot axis has a first section curved to the pivot axis.
6. The safety device according to claim 5, wherein the leg in the first plane or a second plane vertical to the pivot axis has at least a second section adjacent to the first section, wherein the second section has a curvature oriented opposite the first section.
7. The safety device according to claim 6, wherein the leg in the first plane, the second plane or a third plane vertical to the pivot axis has at least a third section adjacent to the second section, wherein the third section has a curvature oriented opposite the second section.
8. The safety device according to claim 1, wherein a first section of the leg has an almost horizontal alignment in the main locking position and lies adjacent on the striker.
Description
(1) Other advantages, characteristics and details of the invention result from the following description, at least of a preferred exemplary embodiment to which the invention is not restricted, however, and on the basis of the figures.
(2) These show:
(3) FIG. 1a-1f and FIG. 2a-2b a sectional view of a safety device during an opening process;
(4) FIGS. 2c to 2f a sectional view of the safety device according to FIG. 1a during a closure process;
(5) FIG. 3 a sectional view of the safety device according to FIG. 1a and a front hood arranged on a striker.
(6) FIG. 1a to 1f and FIGS. 2a to 2b show a safety device 1 for a motor vehicle during an opening process. The safety device 1 has a striker 2, a pawl 3 and a rotary latch 4. The rotary latch 4 has a load arm 5, a catch arm 6, an opening direction of rotation 7, a closing direction of rotation 8, a pre-locking position and a main locking position. Furthermore, the safety device 1 has an ejection spring 9 which is tensioned in the closure direction 8 of the rotary latch 4 to eject the striker 2 and acts on the rotary latch 4 in the opening direction of rotation 7. The ejection spring 9 preferably has a fixed end 36, which is braced on a static support 37 of the safety device 1. The fixed end 36 advantageously extends to a bearing socket 25 and surrounds the bearing socket 25, such that the fixed end 36 is immobile in relation to the pivot axis 34 of the ejection spring 9. The pawl 3 has a pawl spring 10 which acts on the pawl 3 in a locking direction of rotation 11. Furthermore, the pawl 3 has a latch nose 12 which secures the rotary latch 4 in the main locking position of the rotary latch 4 shown in FIG. 1a against rotation in the opening direction of rotation 7.
(7) The catch arm 6 and the load arm 5 form a fork-shaped infeed section 13 of the rotary latch 4 which accommodates the striker 2. The load arm 5 and the catch arm 6 are formed at least partially arch-shaped in order to enable guidance of the striker 2 within the infeed section 13 during a closure movement and an opening movement of the rotary latch 4.
(8) The catch arm 6 has a head area 14 with a bending tangent 15 in the direction of the opening direction of rotation 7, wherein the bending tangent 15 forms a pre-ratchet 16. Furthermore, the load arm 5 has a head area 17 with a bending tangent 18 in the direction of the opening direction of rotation 7, wherein the bending tangent 18 forms a main ratchet 19. In the main locking position of the rotary latch 4 shown in FIG. 1a the latch nose 12 surrounds the main ratchet 19. In the main locking position of the rotary latch 4 the ejection spring 9 furthermore acts on the rotary latch 4 in the direction of the opening direction of rotation 7 by means of the striker 2, wherein the main ratchet 19 presses against the latch nose 12 of the pawl 3 and thus generates pressure on a contact surface of the latch nose 12, which additionally holds the pawl with the force acting by means of the pawl spring 10 in a locked position shown in FIG. 1a.
(9) The rotary latch 4 can be loosened by means of a rotation of the pawl 3 against the locking direction of rotation 11 to a release position from the pre-locking position and from the main locking position. If the load arm 5 or the catch arm 6 of the rotary latch 4 can be passed in the opening direction of rotation 7 on the latch nose 12 of the pawl, the pawl 3 is located in the release position.
(10) The ejection spring 9 is preferably formed as a leg spring, wherein the ejection spring 9 has a leg 27 and a main spring material which lends the ejection spring 9 spring stiffness. The main spring material is preferably metal. It is provided for that the striker 2 lies directly adjacent to the leg 27 in the main locking position, preferably on the main spring material. A configuration within the scope of the invention provides for the main spring material being equipped with a protective cover, wherein the protective cover is viewed as part of the leg 27. In this case, the leg 27 lies directly adjacent to the striker 2 in the main locking position.
(11) FIG. 2b shows the rotary latch 4 in an open position in which the striker 2 is released from the load arm 5 of the rotary latch 4, i.e. blockage of a movement of the striker 2 upwards by the load arm 5 is cancelled. FIG. 1d shows the rotary latch 4 in an intermediate position in which the rotary latch 4 is located between the main locking position and the open position and is rotated into the opening direction of rotation 7 starting from the main locking position. In the intermediate position shown in FIG. 1d, the leg 27 lies directly on a tappet 21 of the rotary latch 4, i.e. on the rotary latch 4. In a special configuration, the tappet 21 is part of the surface of the catch arm 6. In any case, the tappet 21 is connected to the catch arm 6, so that a relative speed between the tappet 21 and the rotary latch 4 is equal to zero and thus direct adjacency of the leg 27 to the tappet 21 corresponds to direct adjacency of the leg to the rotary latch 4.
(12) In the open position of the rotary latch 4 shown in FIG. 2b, the leg 27 also lies adjacently directly on the rotary latch 4. Furthermore, in the open position a contact between the striker 2 and the leg 27 is lifted.
(13) As the leg 27 lies directly adjacent to the rotary latch 4 in the open position of the rotary latch 4, the rotary latch 4 is acted on in the opening direction of rotation 7, and the catch arm 6 is kept depressed against the striker 2. Thus, by means of the ejection spring 9, a lifting force can be transmitted on the striker 2 and a contact between the catch arm 6 and the striker 2 is ensured in the open position of the rotary latch 4.
(14) Maintenance of a contact between the catch arm 6 and the striker 2 during ejection of the striker 2 can reduce noise during ejection of the striker 2 compared to a configuration in which the leg 27 lies adjacent on the striker 2 in the open position and can cause stopping of the striker 2 on an internal surface of the load arm 5.
(15) Furthermore, as shown in FIG. 2b, a lifting force acting directly on the rotary latch 4 during opening of the rotary latch 4 to the open position can enable enlargement of a stroke path 22 of the striker 2 compared to a variant in which the leg 27 lies adjacent solely on the striker 2 during opening of the rotary latch 4. An increase of the stroke path 22 increases operator convenience of a front hood connected to the striker 2 to the extent that an engagement area is increased between an edge of the front hood and a further edge of a motor vehicle chassis located thereunder, wherein grasping of the front hood is facilitated.
(16) In the embodiment of the safety device 1 shown in FIGS. 1a to 1f and 2a to 2f, the ejection spring 9 has a pivot axis 34, which is arranged in a displaced manner to a pivot axis 20 of the rotary latch 4. A lever arm 26 shown in FIG. 1a, which extends between the central point of the striker 2 and the pivot axis 34 of the ejection spring 9 is enlarged by means of the displaced pivot axes 34 and 20 compared to a safety device in which the ejection spring 9 and the rotary latch 4 have a common pivot axis. In a different configuration, the rotary latch 4 and the ejection spring 9 have a common pivot axis. This has the advantage of a more compact design and weight saving.
(17) Hereafter, the image plane of FIG. 1a is viewed which is aligned vertically to the pivot axis 34 of the ejection spring 9 and constitutes a first plane.
(18) The leg 27 of the ejection spring 9 has a first section 28, which is curved in the first plane to the pivot axis 34 of the ejection spring 9 and preferably lies adjacent to a coil of the ejection spring 9.
(19) The first section 28 is concave, i.e. curved inwards, wherein the inside in relation to the leg 27 is defined by the side on which the pivot axis 34 of the ejection spring 9 is located. In the main locking position of the rotary latch 4 illustrated in FIG. 1a, the first section 28 lies adjacent on the striker. The concave curvature of the first section 28 of the leg 27 can cause reduction of a stroke section 29 of the striker 2 for each covered pivot angle 30 of the leg 27, hereinafter known as relative stroke section of the striker 2 during rotation of the leg 27, starting from the main locking position of the rotary latch 4 in the opening direction of rotation 7, compared to a variant in which the leg 27 has a straight first section 28.
(20) The reduced relative stroke section of the striker 2 during rotation of the leg 27 in the opening direction of rotation 7 can cause the work emitted by the ejection spring 9 for each stroke section of the striker 2 to be increased and the spring force of the ejection spring 9 acting on the striker 2 to thus be increased. Thus, in this configuration shown in FIG. 1a, the ejection spring 9 can thus have smaller dimensions, wherein the weight and the necessary installation space of the safety device 1 can be reduced. FIG. 1a furthermore shows that the first section 28 in the main locking position includes an angle of approximately 12 degrees with a horizontal line in the image plane of FIG. 1a, i.e. is aligned almost horizontally.
(21) Furthermore, the leg 27 has a second section 31 adjacent to the first section 28, wherein the second section 31 has a curvature of an opposite orientation to the first section 28. The second section 31 is convex, i.e. curved outwards, wherein the external side is defined by the side which lies opposite viewed from the leg 27 on which the pivot axis 34 of the ejection spring 9 is located.
(22) The convex curvature of the second section 31 can cause an increase in the relative stroke section of the striker 2, wherein acceleration of the striker 2 which is caused by the ejection spring 9 can be reduced if the striker 2 glides along the second section 31. As explained in the general description, reduction of the acceleration of the striker can reduce a noise during adjacency change.
(23) An adjacency change of the leg 27 during ejection of the striker 2 from an adjacency of the leg 27 to the striker 2 to an adjacency of the leg 27 on the rotary latch 4 is described hereafter. Starting from the main locking position of the rotary latch 4 shown in FIG. 1a, the pawl 3 is transferred from the locked position, preferably by means of an electrical drive, into the release position shown in FIG. 1b. The rotary latch 4 released in the opening direction of rotation 7 is accelerated by means of the ejection spring 9 via contact between the striker 2 and the load arm 5 and is rotated into the position shown in FIG. 1c.
(24) FIG. 1c shows the rotary latch 4 in a position between the main locking position and a pre-locking position shown in FIG. 1e. Compared to the position of the rotary latch 4 shown in FIG. 1b the leg 27 is pivoted around an angle 32 in the opening direction of rotation 7 and the striker 2 is lifted upwards around a stroke section 33. A relative stroke section of the striker 2 is calculated, for example, in the position of the rotary latch 4 shown in FIG. 1c from the quotient of the stroke section 33 as a numerator and the covered pivot angle 32 of the leg 27 as a denominator. In the position of the rotary latch 4 shown in FIG. 1c, the leg 27 lies adjacent on the striker 2, but not on the rotary latch 4 or the tappet 21. Furthermore, in the position of the rotary latch 4 shown in FIG. 1c, the bending tangent 15 is blocked by a boom of the pawl 3. After such a blockage, the pawl 3 rotates in an impinged manner by the pawl spring 10 into the locking position which is shown in FIG. 1d, wherein the blockage by the boom is lifted.
(25) Starting from the position of the rotary latch 4 shown in FIG. 1c, the rotary latch 4 is rotated by means of the ejection spring 9 via the striker 2 and a contact between the striker 2 and the load arm 5 in the opening direction of rotation 7. Shortly before attainment, preferably roughly with a pivot angle of 2 to 5 degrees before attainment, of the pre-locking position of the rotary latch 4 the leg 27 lies adjacent to the tappet 21. Simultaneously, the leg 27 lies adjacent on the striker 2. The second curved section 31 preferably extends beyond the edges shown in the Figures in the direction of the open end of the leg 27 and is curved convexly in this configuration that the leg 27 lies directly adjacent during further rotation of the rotary latch 4 from the position of the rotary latch 4 shown in FIG. 1d both on the striker 2 and also on the tappet 21. Thus, a relative speed can be reduced to practically zero between the leg 12 and the tappet 21 during impacting of the leg 27 on the tappet 21, wherein a noise is reduced during impacting of the leg 27 on the tappet 21.
(26) FIG. 1e shows the rotary latch 4 in the pre-locking position, wherein the pawl 3 blocks the catch arm 6 and thus the rotary latch 4 in the opening direction of rotation 7. In the pre-locking position the leg 27 lies directly adjacent both on the striker 2 and also on the tappet 21 and thus on the rotary latch 4. Starting from the pre-locking position of the rotary latch 4 shown in FIG. 1e, the pawl 3 is rotated from the locking position to the release position. This can preferably occur manually. In the release position of the pawl 3, the rotary latch 4 is released in the opening direction of rotation 7 and is accelerated by means of direct contact between the leg 27 and the tappet 21 by means of the ejection spring 9 in the opening direction of rotation 7, as shown in FIG. 1f.
(27) FIG. 2a shows a position of the rotary latch 4, in which the rotary latch 4 is pivoted in an opening direction of rotation 7 compared to the position shown in FIG. 1f. In this position of the rotary latch 4, in which the rotary latch 4 is still not in the open position, contact is canceled between the leg 27 and the striker 2 and the leg 27 lies adjacent on the tappet 21. The movement course starting from FIG. 1c via FIG. 1d, FIG. 1e, FIG. 1f to FIG. 2a shows an adjacency change of the leg 27 from the striker 2 to the rotary latch 4, wherein the leg 27 is formed in such a way that, during adjacency change, a traction is provided for between the leg 27 and the striker 2. In each of the positions of the rotary latch 4 attained during adjacency change, traction is provided for between the leg 27 and the striker 2, either by means of direct contact between the leg 27 and the striker 2 or by means of direct contact of the leg 27 with the tappet 21 in conjunction with direct contact between the catch arm 6 and the striker 2.
(28) This adjacency change causes the leg 27 of the ejection spring 9 to span a larger angular area than the rotary latch 4 during ejection of the striker 2. This has the advantage that, compared to a variant without such an adjacency change, the ejection spring 9 is relaxed more greatly, wherein the ejection spring 9 emits greater work directly or indirectly on the striker 2. This has the advantage that the ejection spring 9 can have smaller dimensions and thus the installation space and the weight of the safety device 1 can be reduced.
(29) FIGS. 2a to 2f show a closure process of the safety device 1. Starting from the open position of the rotary latch 4 shown in FIG. 2a the striker 2 moves the rotary latch 4 into the closing direction of rotation 8 by means of the catch arm 6. During movement of the rotary latch 4 from the open position in the direction of the pre-locking position, the bending tangent 15 of the head area 14 impacts on the catch arm 6 on the latch nose 12 of the pawl 3, as shown in FIG. 2d. After impacting of the bending tangent 15 on the latch nose 12 the catch arm 6 pushes the pawl 3 starting from the locked position in the direction of the release position, wherein the catch arm 6 can pass the latch nose 12.
(30) FIG. 2c shows the catch 4 in the pre-locking position after the catch arm 6 has passed the latch nose 12 and the pawl 3 was moved by means of the pawl spring 10 into the locked position. This position can be assumed, for example, if a front hood to which the striker 2 is attached was not depressed with sufficient force so that the rotary latch 4 attains the main locking position with one-time depression. Latching of the rotary latch 4 in the pre-locking position during a closure process of the safety device 1 prevents the rotary latch 4 reaching the open position again and thus prevents snapping open of the front hood.
(31) If, starting from the pre-locking position of the rotary latch 4 shown in 2e the striker 2 is once again depressed, the bending tangent 18 impacts on the head area 17 of the load arm 5 on the latch nose 12 and rotates the pawl 3 into the release position in which the load arm 5 can pass the latch nose 12. After the load arm 5 has passed the latch nose 12, the pawl spring 10 moves the pawl 3 into the locking position in which the latch nose 12 encompasses the bending tangent 18 of the head area 17 of the load arm 5 and the rotary latch 4 assumes the main locking position.
(32) FIG. 3 shows a front hood 66 arranged on the striker 2, as can be provided for, for example, in the safety device 1 located in a state installed in a motor vehicle. The safety device 1 is preferably arranged in a front area of the front hood 66. Alternatively, the safety device 1 can be arranged in a rear area of the front hood 66.
