1. Field of the Invention
The invention relates to a device for actuating locks on hatches or doors of vehicles, comprising a rotary latch in the lock that is spring-loaded into its open position, wherein the rotary latch, when the hatch or the door is closed, receives a lock member provided stationarily on the vehicle and is rotated into at least one defined position (locked position). The device further comprises a detent on the rotary latch into which, upon rotation of the rotary latch, a catch, pivotably and stationarily supported in the lock, drops so as to define a blocking position of the catch and to secure the locked position of the rotary latch. The device further comprises a catch spring that forces the catch into the blocking position. An actuation that is operated manually or by means of a motor is provided for lifting the catch from its blocking position into a release position in which the rotary latch is released. A snow load device is provided in the lock which, when actuated, holds the catch in the release position until the rotary latch has reached its open position.
2. Description of the Related Art
The classical components of a lock include a spring-loaded rotary latch which upon closing of the door cooperates with a stationary lock member and a spring-loaded, pivotably supported catch that, when closing the door, drops into at least one detent of the rotary latch. The described device also includes a so-called snow load device. The snow load device is needed when upon electric and/or manual actuation of the catch the rotary latch remains in its locked position and does not release the lock member. Despite actuation, the door cannot be opened in this situation.
This “snow load situation” occurs for a lock arranged on the rear hatch of a vehicle when a snow load is present on the closed rear hatch. The weight of the snow presses the rear hatch so tightly into the lock member that the return force of the seal and/or the spring load is not sufficient for transferring the rotary latch into the open position. The term “snow load situation” has been derived from this situation. Without a snow load device, the catch would be returned by the catch spring into the blocking position so that it drops into a detent of the rotary latch and therefore secures the rotary latch again in the locked position. The snow load device has the task of securing the catch in the release position caused by its actuation until the rotary latch has actually reached its open position. The result is that after removal of the snow load from the rear hatch the already released rotary latch is returned by its spring load into the open position without this requiring renewed actuation.
Aside from such a snow load situation there are also other disturbance situations in these devices where the use of such snow load devices is very desirable. In the case of rotary latches that have in addition to the so-called main detent also a pre-detent, it can occur that a rotary latch that is secured by the catch in its main detent will not return quickly enough upon actuation of the catch into its open position but instead its pre-detent is engaged by the catch. It is then necessary to actuate the catch again; this is perceived as cumbersome. In this situation, such a snow load device is also helpful.
Locking devices with snow load devices of this kind are known in various embodiments. The device according to German patent 38 01 158 C1 requires several parts for securing the catch in its release position, e.g. a blocking lever with a stop arm, a driver pin on the rotary latch, and an auxiliary lever. The known snow load devices are expensive and require a large space.
U.S. Pat. No. 6,109,671 discloses a lock in which the force of the catch spring acts always in the same direction on the catch; however, this force can be made inactive by providing additional safety means. These safety means are comprised of a U-shaped hook bracket on a driver that is connected fixedly to the catch and of control surfaces as well as a projection on the rotary latch. In the snow load situation, the hook bracket engages from behind the projection so that the driver is supported on the rotary latch and generates a spacing between the rotary latch and the catch. The force of the catch spring that is still active in the snow load situation is transmitted by the driver onto the rotary latch. These securing means take up a large space within the lock.
It is an object of the present invention to develop a reliable device of the aforementioned kind that is small in size and saves space and is inexpensive.
In accordance with the present invention, this is achieved in that the catch spring is configured as an over-center helper spring that, when the catch moves between its blocking position and its release position, reverses the direction of its spring force and in that the snow load device consists only of the over-center helper spring that interacts with the catch and with the rotary latch.
The invention proposes that the catch spring is a so-called over-center helper spring. When the catch moves between its blocking position and its release end position, this over-center helper spring changes the direction of its spring force. While the catch in the blocking position is loaded by the over-center helper spring in the direction toward the rotary latch, in the release end position the spring force is oriented away from the rotary latch. In the present invention, the snow load device is practically comprised only of the over-center helper spring that interacts with the catch and with the rotary latch. This is sufficient for configuring a snow load device. According to the invention, the snow load device requires no additional components. It is sufficient to have available the elements that are present within a lock in any case, i.e., the catch, the catch spring, and the rotary latch. Accordingly, the special components of the known snow load devices as disclosed in the art are no longer needed. Not only is it no longer required to produce and mount these special components, but valuable space within the lock is made available. The invention is of a very simple configuration so that the device will cause no disruptions or failure. The device according to the present invention functions very reliably.
In the context of the invention, when the term door is used, it is to be understood to encompass any type of hatch, door or door-like closure device of a vehicle that is provided with a lock.
Such an over-center helper spring has two spring ends, wherein the first spring end engages the catch and forms a moving end of the spring that can be moved together with the catch, wherein the second spring end is stationary within the lock and provides a fixed spring end of the over-center helper spring. An imaginary straight connecting line between the pivot bearing of the catch and the fixed end of the over-center helper spring determines a dead-center line for the over-center helper spring. The moving end of the over-center helper spring upon pivoting of the catch crosses the dead-center line and determines on opposed sides of the dead-center line two stable end positions of the over-center helper spring. The over-center helper spring in the first end position generates on the catch a (first) torque and in the second end position generates on the catch an oppositely oriented (second) counter torque, wherein the first torque forces the catch into its blocking position and the second (counter) torque forces the catch into its release position.
Additional features and advantages of the invention result from the dependent claims, the following description, and the drawings. The drawings show three embodiments of the invention. Only those components essential for understanding the invention are illustrated. The device according to the invention is configured in other respects as is customary in the art.
In the drawing:
When supposing that each lock of the inventive kind comprises a rotary latch 20 and a catch 30, a snow load device 10 is comprised according to the invention only of the special configuration of the catch spring 40, i.e., it is a so-called over-center helper spring. As already mentioned, in the first embodiment this over-center helper spring is a tangentially loaded helical spring (“leg spring”). Since each lock requires a single catch spring 40, it can be said that the snow load device according to the invention is characterized by the special feature of requiring no additional lock parts.
The rotary latch 20 is supported so as to rotate on a stationary rotary pin 21 in the lock housing (not illustrated in detail) and is exposed to the action of a spring load that is illustrated by the arrow 22. This spring load 22 has the effect of transferring the rotary latch 20 into the open position illustrated in
The open position 20.1 of the rotary latch 20 shown in
When locking the rear hatch manually or by means of a motor, the rotary latch 20 reaches its locked position illustrated in
The over-center helper spring 40 embodied in the first embodiment as a tangentially loaded helical spring is comprised of a coil 43 from which two legs 44, 45 project. The free ends of these legs 44, 45 form two spring ends 41, 42 of which one spring end 41 engages the catch 30 and therefore is entrained when the catch 30 is pivoted; this end is referred to in the following as the moving end. The other spring end 43, on the other hand, is stationarily supported in the lock housing and is at rest. It is therefore referred to as the fixed end of the over-center helper spring 40. The over-center helper spring 40 always exerts a spring force that has the effect of spreading apart the two legs 44, 45. This is illustrated by the force arrows 47 in
The over-center helper spring 40 has a so-called dead center line 46 relative to which the moving end 41 can be positioned in two opposed positions. The dead center line 46 is determined by an imaginary straight connecting line between the pivot support 31 of the catch 30 and the fixed end 42 of the over-center helper spring 40. As a function of the different pivot positions, different actions occur on the catch 30.
When the locked position 20.2 of the rotary latch 20 according to
The position illustrated in
In the intermediate position 30.0 of
In the release end position 30.1, the moving end 41 of the over-center helper spring 40 is located relative to the dead center line 46 on the side remote from the rotary latch 20. Because of the stop 14 for the catch, a second end position marked in the drawing by the auxiliary line 48.2 of the moving end 41 is thus present. The force conditions that have been explained in connection with
As already mentioned, the catch 30 has released the rotary latch 20 in its dead center position 30.0 of
However, the special snow load situation mentioned above can occur in which the rotary latch 20, even after release of the catch 30 according to
Because of the counter torque 32.1 in
The catch 30 has in addition to the arm 34 with locking effect also a counter arm 35 on its opposite side relative to the pivot bearing 31. On the counter arm 35 a control surface 37 is provided in the form of an angled projection 38. In the present case, the already mentioned circumferential contour 25 of the rotary latch 20 is a circle relative to the rotary pin 21. The rotary path resulting when the rotary latch 20 finally returns in the direction of the movement arrow 26 of
In the locked position 20.2 of the rotary latch 20, the engagement depth of the counter detent 33 of the catch 30 in the detent 23 can be limited by a shoulder 16 that is supported in a springy fashion on a matching counter shoulder of the rotary latch 20 because of the described catch torque 32.2. This is illustrated in
The invention is not only of interest for a snow load situation. With the device according to the invention, the rotary latch 20 has always sufficient time as a result of its spring load 22 for moving from its locked position 20.2 of
As already mentioned,
The latter holds true also for the third embodiment according to
While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.
Number | Date | Country | Kind |
---|---|---|---|
10 2004 033 735.7 | Jul 2004 | DE | national |