MOTOR VEHICLE LOCK, IN PARTICULAR A MOTOR VEHICLE BONNET LOCK

Abstract

A motor vehicle lock, in particular a motor vehicle bonnet lock. Same is designed with a locking mechanism substantially formed by a rotatory latch and a pawl for cooperating with a locking bolt. In addition, a catch hook is provided for independent and additional securing of a locking bolt. The locking mechanism is provided with a locking mechanism drive and the catch hook is provided with a catch hook drive. According to the invention, the locking mechanism drive and the catch hook drive are optionally actuated by motor vehicle signals.

Claims

1. A motor vehicle lock comprising: a locking mechanism including a rotary latch and a pawl for interacting with a locking bolt, and a catch hook for independent and additional securing of the locking bolt relative to the locking mechanism, wherein the locking mechanism is equipped with a locking mechanism drive and the catch hook is equipped with a catch hook drive, and the locking mechanism drive and the catch hook drive are selectively actuated according to a motor vehicle signals.

2. The motor vehicle lock according to claim 1, wherein the motor vehicle signals includes one or more of a motor vehicle speed, an opening signal in the motor vehicle interior, an opening signal in the motor vehicle luggage compartment, a motor vehicle brake signal, and a motor vehicle tilt signal.

3. The motor vehicle lock according to claim 1, wherein a control unit is provided to control the locking mechanism drive.

4. The motor vehicle lock according to claim 3, further comprising a safety unit independent from the control unit that is provided to control the catch hook drive.

5. The motor vehicle lock according to claim 4, wherein the safety unit is downstream from the control unit.

6. The motor vehicle lock according to claim 4, wherein the safety unit and the control unit simultaneously process the motor vehicle signal.

7. The motor vehicle lock according to claim 4, wherein the safety unit controls the catch hook drive to open the catch hook depending on the motor vehicle signal, or galvanically isolates an electrical supply line of the catch hook drive so that the catch hook cannot be opened.

8. The motor vehicle lock according to claim 4, wherein the safety unit actuates the catch hook drive with priority over the control unit.

9. The motor vehicle lock according to claim 1, wherein the catch hook drive is configured to open the catch hook and additionally to mechanically block the catch hook in the absence of a release signal.

10. The motor vehicle lock according to claim 1, wherein the locking mechanism drive is configured to open the locking mechanism by lifting the pawl out of the rotary latch.

Description

[0025] In the following, the invention is explained in greater detail with reference to a drawing showing just one example of an embodiment:

[0026] FIG. 1 shows the motor vehicle lock according to the invention in the form of a motor vehicle hood lock reduced to the essential components in its basic features, and

[0027] FIG. 2 shows the circuitry for activating the motor vehicle lock, or motor vehicle hood lock according to FIG. 1.

[0028] FIG. 1 shows a motor vehicle lock in the form of a motor vehicle hood lock. In FIG. 1, it can be seen that the motor vehicle lock or the motor vehicle hood lock is equipped with a lock case in which a locking mechanism 1,2 consisting of a rotary latch 1 and a pawl 2 are rotatably mounted. The locking mechanism 1, 2 interacts with a lock holder, or respectively a locking bolt 3 of the lock holder. An additional ejector, which is not shown, may ensure that the locking bolt 3 is actuated in the opposite direction to the closing direction indicated by an arrow in FIG. 1 after an opening process.

[0029] Once the locking bolt 3 moves into an inlet opening 4 in the lock case in the closing direction shown in FIG. 1, the rotary latch 1 is swung in the clockwise direction indicated in FIG. 1, so that the pawl 2 can, with a hook-shaped contour 5, grasp behind an extension 6 of the rotary latch 1 in a latching manner in the then achieved closed state of the latch 1,2. This moves the locking bolt 3 against a stop surface 7 of the rotary latch 1.

[0030] In the closed position of the shown motor vehicle lock or hood lock, the locking bolt 3 is additionally secured with the assistance of a catch hook 8 which is actuated for this purpose in the indicated counterclockwise direction about its axis with the assistance of a spring (not shown), and secures the locking bolt 3 in addition to the rotary latch 1. Within the scope of the exemplary embodiment, the locking mechanism 1, 2 now has an electromotive locking mechanism drive 9, and an electromotive catch hook drive 10 is also realized.

[0031] With reference to a comparative consideration of FIGS. 1 and 2, it can be seen that the locking mechanism drive 9 and the catch hook drive 10 are selectively actuated in accordance with motor vehicle signals 11. According to the exemplary embodiment, the motor vehicle signals 11 are for example the motor vehicle speed, which is below a limit speed of, for example, 5 to 6 km/h. Only then is the motor vehicle speed or the relevant motor vehicle signal 11 evaluated by a control unit 12 or a safety unit 13 such that control of the relevant drive 9, 10 is permitted at all.

[0032] In fact, it can be seen in the schematic representation of the realization of the circuitry according to FIG. 2 that, in addition to the control unit 12, the safety unit 13 is also realized, with the assistance of which at least the catch hook drive 10 is controlled. Moreover, an opening signal 14 can also be seen in FIG. 2 that can be generated from the vehicle interior by a vehicle user. Furthermore, another opening signal 15 can be generated inside a luggage compartment closed with the assistance of a hood bearing the locking bolt 3, for example by a person located there.

[0033] With reference to the circuit overview according to FIG. 2, it can be seen that the safety unit 13 is designed independently of the control unit 12 and, according to the exemplary embodiment, only serves and is used to control the catch hook drive 10. Moreover, the safety unit 13 is downstream from the control unit 12. Both the safety unit 13 as well as the control unit 12 can simultaneously process the motor vehicle signals 11. Finally, the design is such that the safety unit 13 actuates the catch hook drive 10 with priority over the control unit 12. That is, any controls or enable signals from the safety unit 13 for the catch hook drive 10 take precedence, so that additional signals from the control unit 12 may be or can be ignored in certain circumstances.

[0034] The overall design is as follows. In order to open the hood equipped with the closing bolt 3, an opening signal 14, 15 must first be present. One of the two opening signals 14, 15 are sufficient for this. The relevant opening signal 14, 15 is evaluated and detected by the control unit 12. In addition, the control unit 12 in the exemplary embodiment evaluates the vehicle speed 11. If the vehicle speed 11 is below the aforementioned limit value, the control unit 12 sends a signal to the locking mechanism drive 9. To open the locking mechanism 1, 2, the locking mechanism drive 9 acts on the pawl 2 and ensures, corresponding to the direction of the arrow indicated in FIG. 1, that the pawl 2 is lifted from its engagement with the rotary latch 1 into the closed position of the locking mechanism 1, 2. As a result, the hook or the hook-shaped contour 5 on the pawl 2 comes free from the extension 6 of the rotary latch 1 so that the rotary latch 1 swings open sufficiently for the locking bolt 3 to move upwards against the closing direction marked in FIG. 1. As before, the catch book 8 still remains engaged with the locking bolt 3, however.

[0035] The catch hook drive 10 can now be controlled in turn and indirectly via the safety unit 13. For this purpose, the motor vehicle signal 11 is redundantly checked by both the control unit 12 as well as by the safety unit 13. If the safety unit 13 determines that the vehicle signal 11 meets the required criterion, the safety unit 13 as a whole ensures that the catch hook drive 10 actuates the catch hook 8 in the indicated direction of the arrow according to FIG. 1, therefore lifting it out of its engagement with the locking bolt 3 against the force of the spring. As a consequence of this, the hood comes free and can be completely opened.

[0036] However, if the safety unit 13 determines that the motor vehicle signal 11 does not meet the requirements for a release signal for the catch hook 10 to be generatable by the safety unit 13, the safety unit 13 either ensures that an electrical supply line for the catch hook drive 10 is galvanically isolated, or alternatively, it is also possible for the safety unit 13 to actuate the catch hook drive 10 to mechanically block the locking bolt 3 in the absence of a release signal.

[0037] Any malfunction of the locking mechanism 1,2 and/or the control unit 12 is ignored since the safety unit 13 is solely responsible for the actuation of the catch hook drive 10, taking priority over the control unit 12. Therefore, for example, if discrepancies are observed during the evaluation of the motor vehicle signal 11 and the redundant test by the control unit 12 and the safety unit 13, the safety unit 13 ensures, in each case and for safety reasons, that the electrical supply line to the catch hook drive 10 is galvanically isolated, or that the catch hook drive 10 is actuated to block the locking bolt 3. In each case, such malfunctions cause the locking bolt 3 to still be secured by means of the catch hook 8, and the associated hood cannot be completely opened. The catch hook drive 10 can be designed in two parts overall, with a first drive part which actuates the catch hook 8 in a clockwise direction to release the locking bolt 3 and another, second drive part which ensures that the catch hook 8 is blocked in the absence of a release signal from the safety unit 13. At the same time, a single drive can also be used at this juncture.

[0038] If, for example, there is an opening request from the luggage compartment by the opening signal 15 while the motor vehicle is driving, the control unit 12 ensures in this case that the locking mechanism 1,2 is opened, but the catch hook 8, however, still secures the locking bolt 3. Consequently, any person located in the luggage compartment receives breathing air through the gap created in this way between the hood and the vehicle body, and the hood remains secured as before and unchanged with the assistance of the catch hook 8. In this case, the control unit 12 interprets the opening signal 15 in a corresponding manner, and ignores the additional criterion of the vehicle speed or motor vehicle signal 11. Nonetheless, the safety unit 13 querying the motor vehicle signal 11 ensures, unchanged and as before, that the catch hook 8 is secured, in that either the electrical supply line to the catch hook drive 10 experiences an interruption, or the catch hook drive 10 blocks the catch hook 8.

LIST OF REFERENCE SIGNS

[0039] 1 Rotary latch [0040] 2 Pawl [0041] 1,2 Locking mechanism [0042] 3 Locking bolt [0043] 4 Inlet opening [0044] 5 Hook [0045] 6 Extension [0046] 7 Stop surface [0047] 8 Catch hook [0048] 9 Locking mechanism drive [0049] 10 Catch hook drive [0050] 11 Motor vehicle signals [0051] 12 Control unit [0052] 13 Safety unit [0053] 14, 15 Opening signal