Lock with assisted closing device for a motor vehicle

Abstract

A lock for a motor vehicle, comprising a locking mechanism composed of a rotary latch and at least one pawl, an assisted closing device, an electric drive, and a torque converter, wherein a variable torque is adjustable in the assisted closing device by means of the torque converter, and wherein the assisted closing is achieved at least in some regions by means of a frictional connection.

Claims

1. A lock for a motor vehicle, the lock comprising: a locking mechanism having a rotary latch and at least one pawl, an assisted closing device comprising a pull-handle attached to a Bowden cable, an electric drive, and a torque converter, wherein the torque converter is connected to the electric drive and the Bowden cable is connected to the torque converter, wherein the torque converter is configured to exert different forces or torques into the rotary latch via the Bowden cable and the pull-handle, wherein during a first assisted closing movement of the rotary latch to a closing position in which a gap of 4 mm exists between a door or flap to be closed and a chassis of the motor vehicle, the assisted closing device transmits a first assisted closing toque into the rotary latch via a first force exerted on the Bowden cable by the torque converter and by a frictional connection between the pull-handle and the rotary latch resulting in a first constant uniform force on the rotary latch, and wherein during a second assisted closing movement of the rotary latch from the closing position to a closing of the door or flap, the assisted closing device transmits a second assisted closing torque into the rotary latch via a second force exerted on the Bowden cable by the torque converter and by a form fitting connection between the pull-handle and the rotary latch resulting in a second constant uniform force on the rotary latch.

2. The lock according to claim 1, wherein the rotary latch has a pre-latching position and a main latching position, wherein the pull-handle can engage with the rotary latch when in the pre-latching position and when in the main latching position.

3. The lock according to claim 1, wherein the assisted closing device has a pull-handle and the pull-handle can engage with the rotary latch.

4. The lock according to claim 1, wherein the assisted closing device has the Bowden cable and a transmission.

5. The lock according to claim 4, wherein the frictional connection is formed by the Bowden cable and/or by the transmission and/or by the pull-handle.

6. The lock according to claim 1, wherein the assisted closing torque in the first assisted closing movement is less than the assisted closing torque in the second assisted closing movement.

7. The lock according to claim 6, wherein in the first assisted closing movement, the assisted closing force is 100 Newtons and in the second assisted closing movement, the assisted closing force is 500 Newtons, wherein the first and second assisted closing movement is provided by the assisted closing device.

8. The lock according to claim 1 further comprising a striker, wherein an assisted closing movement of the rotary latch is transmitted into the striker through the engagement of the rotary latch.

9. The lock according to claim 1 further comprising a striker, wherein the first assisted closing movement occurs by engagement of the rotary latch into the striker to the closing position.

10. The lock according to claim 1 further comprising a sensor for recording a position of the locking mechanism, a control unit for the assisted closing device, and at least one medium for detecting a position of a mobile part of the assisted closing device, wherein the at least one medium interacts with the control unit.

11. The lock according to claim 10, wherein the at least one medium is a sensor and/or a switching device.

12. The lock according to claim 10, wherein the at least one medium for detecting the position includes a sensor that interacts with the control unit by detecting a rise in current in the electric drive, wherein the assisted closing process can be interrupted when the rise is detected.

13. The lock according to claim 12, wherein the at least one medium for detecting the position can be used to monitor a gap when closing a moved component.

14. The lock according to claim 13, wherein up to the gap being 6 mm, the interruption of the assisted closing process is controlled by the control unit.

15. The lock according to claim 13, wherein the moved component is a door, flap, cover and/or hood of the motor vehicle.

16. The lock according to claim 10, wherein the at least one medium for detecting the position is located on the rotary latch.

17. The lock according to claim 10, wherein a variable assisted closing torque is provided by the assisted closing device.

18. The lock according to claim 1, wherein the assisted closing device interacts directly with the locking mechanism or a retaining band.

19. The lock according to claim 18, wherein the rotary latch can be moved by the assisted closing device.

20. The lock according to claim 1, wherein the torque converter comprises a sliding clutch connected to the electric drive, wherein the Bowden cable and the sliding clutch are in a semi-engaged connection.

Description

(1) The invention is described in further detail below with reference to the attached drawings on the basis of an exemplary embodiment. However, the principle applies that the exemplary embodiment does not limit the invention, but only constitutes an advantageous embodiment. The characteristics depicted can be executed individually or in combination with further characteristics of the description, as can the patent claims be executed individually or in combination.

(2) Depicted are:

(3) FIG. 1 is a drawing depicting an illustration of a part of an assisted closing device in a motor vehicle lock with a locking mechanism with a pre-ratchet and main ratchet.

(4) FIG. 2 is a drawing depicting a force route diagram with an illustration of a force course via a first assisted closing movement and a second assisted closing movement.

(5) FIG. 3 is a drawing depicting a force route diagram with an illustration of a force course via a first assisted closing movement and a second assisted closing movement with a limit force line.

(6) FIG. 1 shows a part of a motor vehicle lock 1. It shows a locking mechanism 2 from a rotary latch 3, a pre-latching pawl 4 and a main latching pawl 5. The rotary latch 3 is pivotably accommodated around an axis 6 and pawls 4, 5 around an axis 7. In order to obtain a closing position, the rotary latch 3 can be pivotably accommodated around the axis 6 in the direction of the arrow P, for example in a lock plate of the motor vehicle lock 1. FIG. 1 shows the pre-latching position, whereby the pre-ratchet pawl 4 can engage with a ratchet contour 8 on the rotary latch 3.

(7) Also shown as part of the assisted closing device 9 is a pull-handle 10, a recess 11, a traction means 12 and a Bowden cable core 13, whereby the traction means 12 and the Bowden cable core 13 can be part of a Bowden cable 12, 13. The pull-handle 10 is pivotably accommodated in the motor vehicle lock via an assisted closing path Z. The assisted closing path Z is shown as a dot-dashed line and as a circular arc in FIG. 1. Also shown is the striker 14, whereby the striker 14 has already engaged with the rotary latch 3 in the pre-latching position.

(8) The pull-handle 10 and rotary latch 3 can respectively have a contour 15, 16 that is designed such that when the striker 14 reaches the rotary latch 3, a frictional connection, in other words for example a frictionally engaged connection, can be established between the pull-handle 10 and rotary latch 3. On the one hand, the rotary latch contour 15 and also the pull-handle contour 16 can be designed such that a frictional connection can be established in a first assisted closing path, whereas a form fit can be obtained on a second assisted closing path.

(9) FIG. 2 shows a diagram whereby the assisted closing path Z is presented in millimeters above the assisted closing force in Newtons. A pre-latching position VR and a main latching position HR are indicated. In addition to this, an overstroke position H is indicated again since the assisted closing device 9 moves the rotary latch in an overstroke position so that the main ratchet pawl 5 can engage in the ratchet contour 8. There is mostly a pre-latching position for a door gap of approx. 6 mm. In the main latching position, the door is closed. The overstroke position indicates the path of the rotary latch which the rotary latch takes via the main latching position, so that the pawl 5 can engage in the ratchet contour 8 of the rotary latch 3. This exemplary embodiment or the exemplary embodiment in FIG. 1 shows a locking mechanism 2 with two pawls 4, 5. It is of course also conceivable that there is only one pawl 4, 5.

(10) The assisted closing path Z describes the path via which the pull-handle 10 moves the rotary latch 3 driven by an electric motor. According to the invention, the pull-handle 10 already engages when the rotary latch 3 engages with the striker 14. The diagram shown in FIG. 2 shows an assisted closing path Z of 10 mm plus an overstroke. The pull-handle 10 moves the rotary latch 3 in the direction of the arrow P via an assisted closing path from a door gap of 10 mm to a door gap of 4 mm. The rotary latch 3 is hereby moved with a force of 100 Newtons or moved into the closing position. The force course is shown in the diagram by K. The force course via the pre-closure from a door gap of 4 mm to the closing of the door in the main ratchet or into an overstroke H is indicated by FO in the diagram.

(11) As is clearly apparent from FIG. 2, the assisted closing movement according to the invention is not bound to the latching positions VR, HR. Rather, it is conceivable according to the invention to move the frictional connection so far in the direction of the main latching position HR that the door or flap is already mostly closed. Only when great closing forces, for example against the pressure of a door seal, are needed, does this create a form fit FO between the pull-handle 10 and the rotary latch 3, whereby the safe closure and retaining of the rotary latch is facilitated.

(12) The force courses of the assisted closing devices known from the state of the art are also recorded on the diagram. An assisted closing movement in accordance with a progressively increasing force or a progressively increasing torque, is recorded on the diagram with the force line profile 17 and a force that is indirectly introduced with the pre-ratchet for the overstroke with the force line profile 18.

(13) During the assisted closing, a torque is introduced into the rotary latch 3 in the direction of the arrow P by means of the pull-handle 10. The torque is hereby proportional to a power consumption and proportional to a force F that is recorded in FIG. 2 in the y-axis. If during the assisted closing, this now produces a force line profile 17, 18, which is produced via the frictional connection K and the force line profile 17 or 18, then a tolerance window TO can be specified by means of the control unit, that must not be exceeded. If the force F reaches a limit force line 19, as shown by the dashed line in FIG. 2, then there is the possibility that the control unit interrupts the assisted closing process.

(14) If during a normal assisted closing during the frictional connection KO or the form fit FO, an excessive amount of force is applied so that the limit force line 19, thus the tolerance window TO too, is exceeded, then jamming and/or any impediment during the assisted closing can be detected by means of the control unit. As a result of the formation according to the invention and in particular as a result of the recording of the increase in current in the drive, it is hereby possible to determine a malfunction and introduce a suitable countermeasure.

(15) The increase in current is hereby a measure for the proper procedure of the assisted closing process. A malfunction or jamming is hereby detected by means of an excessive current or an excessive force, so that the interruption, uncoupling of the assisted closing drive and/or the reversal of the assisted closing drive, can be initiated.

(16) A sensor as the means for recording a position 20 is shown for example in FIG. 1. The sensor 20 can for example as rotary encoder, record the rotational movement of the rotary latch 3 or for example be designed as a microswitch so that the assisted closing movement Z can also be recorded. The sensor 20 is connected directly to the control unit S, whereby the control unit S in turn monitors the force absorption of the motor M. The control unit is hereby in a position, starting with the movement signal of the sensor 20, to set the power consumption of the motor M into proportion and thus to determine an excessive force or an excessive power consumption of the motor M in relation to the assisted closing process. If the force exceeds the force limit line 19 or if too high a power consumption is determined on the motor M by means of the control unit S, then the assisted closing process can be interrupted. Advantageously, in accordance with FIG. 1, the pull-handle 10 can for example be disengaged from the rotary latch 3.

LIST OF REFERENCE SIGNS

(17) 1 Motor vehicle lock 2 Locking mechanism 3 Rotary latch 4 Pre-ratchet pawl 5 Main ratchet pawl 6, 7 Axis 8 Ratchet contour 9 Assisted closing device 10 Pull-handle 11 Recess 12 Traction means 13 Bowden cable core 14 Striker 15 Rotary latch contour 16 Pull-handle contour 17, 18 Force line profile 19 Limit force line 20 Sensor P Arrow Z Assisted closing path VR Pre-ratchet HR Main ratchet H Overstroke K Frictional connection FO Form fit F Force TO Tolerance window S Control unit M Drive motor