Motor vehicle door lock

Abstract

The invention relates to a motor vehicle door lock comprising a locking mechanism consisting essentially of a rotary latch and a pawl, further comprising an actuation lever mechanism (2a, 2b) that acts on the pawl, and a child safety device (3) that includes a child safety lever (4) to which the force of a spring (5) is applied. According to the invention, the child safety lever (4) and the spring (5) are designed as a subassembly (4, 5).

Claims

1. A motor vehicle door latch with a locking mechanism comprising: an activation lever mechanism that opens the locking mechanism from inside the motor vehicle; and a child lock device moveable between an activated position in which the activation lever mechanism is disconnected from the locking mechanism and a deactivated position in which the activation lever mechanism is connected to the locking mechanism, the child lock device including: a child lock lever that is rotatable and engageable with the activation lever mechanism to block the activation lever mechanism from being connected with the locking mechanism when the child lock device is in the activated position; and a spring connected to the child lock lever, wherein the child lock lever and the spring are integrally formed as a single element, and the spring is deformable to force the child lock device toward the activated position when the child lock lever is in a first intermediate position in which a first pivot angle between the child lock lever and the activated position is less than a second pivot angle between the child lock lever and the deactivated position, and toward the deactivated position when the child lock lever is in a second intermediate position in which the second pivot angle is less than the first pivot angle.

2. The motor vehicle door latch according to claim 1, wherein the child lock lever and the spring are formed from a uniform material.

3. The motor vehicle door latch according to claim 2, wherein the uniform material is plastic.

4. The motor vehicle door latch according to claim 1, wherein the child lock lever includes a guide nut that is arranged between the child lock lever and the spring, and receives a pin.

5. The motor vehicle door latch according to claim 4, wherein the pin is formed as a guiding pin connected to a housing.

6. The motor vehicle door latch according to claim 4, wherein the guide nut has a first end and a second end and the guiding pin is moveable between the first end and the second end, and wherein the child lock device is in the activated position when the guiding pin is at the first end and in the deactivated position when the guiding pin is at the second end.

7. The motor vehicle door latch according to claim 6, wherein the guide nut includes a transition area between the first end and the second end, the transition area having a smaller cross-section than the guiding pin guided therein, the spring being deformable in the transition area when the child lock device is in the intermediate position.

8. The motor vehicle door latch according to claim 7, wherein the spring generates a resetting force on the child lock lever in the transition area, whereby the guiding pin is moved into a closer end of the first end or the second end according to an angular position of the guiding pin.

9. The motor vehicle door latch according to claim 6, wherein the first end and the second end are cross-sectionally enlarged relative to an area of the guide nut between the first end and the second end.

10. The motor vehicle door latch according to claim 4, wherein the guide nut is limited in a lengthwise extension both by a radially internal stop wall in relation to a rotational axis of the child lock lever and a radially external spring wall of the spring.

11. The motor vehicle door latch according to claim 10, wherein the stop wall is formed as a circle center in an arc shape compared to the rotational axis.

12. The motor vehicle door latch according to claim 10, wherein the spring wall is formed as an elastic bridge between the guide nut and a radially external recess.

13. The motor vehicle door latch according to claim 1, wherein the activation lever mechanism includes an internal activation lever that opens the locking mechanism from inside the motor vehicle, and an external activation lever that opens the locking mechanism from outside the motor vehicle, wherein the child lock is engageable with the internal activation lever.

14. The motor vehicle door latch according to claim 1, wherein the child lock device includes an activation nut that is formed integrally with the child lock lever.

Description

(1) Hereinafter, the invention is explained in further detail on the basis of a drawing which only depicts an execution example. It shows:

(2) FIG. 1 the motor vehicle door latch according to the invention in a rear view seen from the inside of the motor vehicle door latch,

(3) FIG. 2 the object according to FIG. 1 in a front view with the activation nut and

(4) FIG. 3A to 3C the child lock device separately in different functional positions.

(5) In the figures a motor vehicle door latch is depicted which is reduced to the components and elements crucial for the invention. A housing 1 is initially apparent which, in the present case, is formed as a plastic lid and latches a non-illustrated latch case. The latch case is typically arranged in a drawing plane above the drawing plane illustrated in FIG. 1 and is not illustrated for reasons of clarity. As usual, the purpose of the latch case is to accommodate a locking mechanism which is also not illustrated, consisting of a catch and a pawl. A partially apparent activation lever mechanism 2a, 2b which is only illustrated in extracts in the internal view according to FIG. 1 and depicts an internal activation component works on the pawl. Furthermore, a child lock device 3 is apparent which is equipped with a child lock lever 4. The child lock lever 4 is impinged by a spring 5. According to the invention, the child lock lever 4 and the spring 5 are formed as a constructional unit 4, 5.

(6) In the illustration according to FIG. 1 or 3A the child lock lever 4 is located in its child lock on position in which the child lock lever 4 interrupts an internal activation lever chain or an internal activation via the activation lever mechanism 2a, 2b pertains to an idle stroke on a non-illustrated internal door handle. In contrast, the position depicted in dot dashes in FIG. 1 or the child lock off position shown in FIG. 3C corresponds to an internal activation being possible via the activation lever mechanism 2a, 2b and consequently the pawl can be lifted from the catch. In both child lock on and child lock off functional positions the illustrated motor vehicle door latch can still be activated externally.

(7) Specifically, the design may be such that the child lock lever 4 apparent in FIG. 1 or 3A in the child lock on position illustrated blocks an internal activation lever 2b as a component of the activation lever mechanism 2a, 2b in this position with a pin 6 located on the end or causes an idle stroke if the internal activation lever is pivoted around its axis in the arrow direction illustrated in FIG. 1. Because hereby the two lever arms connected by a spring are uncoupled from one another or the lever arm running against the stop 6 is blocked. Consequently, this cannot lift the pawl from the catch either directly or indirectly.

(8) The two functional positions illustrated in FIG. 1 or FIG. 3A and 3C child lock on and child lock off of the child lock lever 4 can be specified with the aid of an activation nut 7 in the example case apparent in the front view according to FIG. 2. Instead of the activation nut 7 the child lock lever 4 can naturally also be manually (or even automatically) pivoted to any other type. In the execution example, the activation nut 7 connected integrally with the child lock lever 4 ensures that the child lock lever 4 assumes either its child lock on end position or the child lock off end position with the previously described consequences.

(9) According to the invention, it now not only depends on the child lock lever 4 being able to be transferred into the two end positions illustrated, but these end positions also need to be maintained with positional accuracy. Only thus can unintentional engagement or disengagement of the child lock device 3 or the child lock lever 4 be prevented. For this purpose, the child lock lever 4 possesses the aforementioned spring 5. In fact, the child lock lever 4, 5 and the spring 5 are formed as a constructional unit 4, 5 according to the invention. In the design example, the child lock lever 4 and the spring 5 are designed in a materially uniform manner from plastic, for example. In the design example, the activation nut 7 is added to the constructional unit 4,5. Consequently, a constructional unit 4, 5, 7 comprising the child lock lever 4, the spring 5 and finally the activation nut 7 is present which is designed as a single-component plastic injection molded component 4, 5, 7. Naturally, this only constitutes an example and is not compulsory.

(10) On the basis of the illustration in FIG. 1, it is apparent that the child lock lever 4 is equipped with a guide nut 8 to engage a pin 9. The pin 9 is connected to the housing 1 and in the present case is designed as a guide pin 9 for the child lock lever 4. In fact, the guide pin 9 in conjunction with the activation nut 7 which engages into a pertaining aperture 10 of the housing 1 apparent in FIG. 2 ensures both that a rotational axis 11 of the child lock lever 4 is defined and that the child lock lever 4 is perfectly guided around the rotational axis 11 in this pivoting movement with the aid of the pin 9 engaging into the guide nut 8.

(11) On the basis of FIG. 1 and FIG. 3A to 3C it is apparent that the guide nut 8 is designed in a cross-sectionally enlarged manner in the area of the respective end positions of the child lock lever 4. In fact, the guide nut 8 in the region of the two end positions demonstrates a cross-section which corresponds to the cross-section of the pin or the guide pin 9 engaging into the guide nut 8. In contrast, for a transitional area 12, 13 between the two end positions a cross-section of the guide nut 8 is observed which is less than the cross-section of the guide pin 9. As a consequence hereof, the spring 5 is deformed as illustrated in FIG. 3B.

(12) In fact, in its lengthwise extension the guide nut 8 is limited both by a stop wall 13 and a spring wall 12 as a spring 5. Compared to the rotational axis 11, the stop wall 13 is radially internally arranged compared to the guide nut 8, whereas the spring wall 12 is arranged and corresponds radially externally compared to the rotational axis 11.

(13) It is apparent that the stop wall 13 is arc-shaped compared to the rotational axis 11 which functions as the circle center in this regard. In contrast, the spring wall 12 predominantly has a straight extension. In fact, the spring wall 12 is designed as an elastic bridge 12 between the aforementioned guide nut 8 and a recess 14. The recess 14 ensures that the spring wall 12 acting and functioning as a spring 5 can escape into this recess 14 with any deformation by the guide pin 9 (cf. FIG. 3B). It is apparent that the recess 14 is arranged radially externally compared to the rotational axis 11 of the child lock lever 4, while the guide nut 8 possesses a radially internal arrangement in contrast.

(14) As already explained, the predominantly straight design of the spring wall 12 in conjunction with the arc shape of the stop wall 13 overall leads to the guide nut 8 in the transition area 12, 13 demonstrating a lower cross-section than the guided pin 9 between the two end positions of the child lock lever 4. As a consequence hereof, the pin 9 ensures that the spring wall 12 is elastically deformed in the transition area 12, 13. Due to the elastic deformation, the spring wall 12 generates a resetting force on the child lock lever 4. This is shown in FIG. 3B. It is apparent there that the child lock lever 4 was activated incompletely. Thus, the pin 9 is located in the transition area 12, 13. The spring wall 12 is elastically deformed and generates a resetting force in a counterclockwise direction in relation to the rotational axis 11. Thus, the incompletely activated child lock lever 4 is impinged in the direction of the child lock off position according to FIG. 3C.

(15) The resetting force of the spring wall 12 is calculated in such a way that the child lock lever 4 is transferred into one of the end positions according to its angular position compared to the rotational axis 11. However, overall this ensures that the child lock lever 4 is perfectly positioned even if the child lock lever 4 has been incompletely impinged with the aid of the activation nut 7. In this case, the spring wall 12 is deformed in the transition area 12, 13, which functions as a spring 5 ensures that the resetting force generated by the deformation transfers the child lock lever 4 into the next angular end position. The next angular end position corresponds to a smallest pivot angle in relation to the two fundamentally attainable end positions.

(16) Consequently, if the guide pin 9 plunged into the guide nut 8 is located in closer angular proximity to the child lock on end position than to the child lock off end position, the resetting force generated by the deformation of the spring wall 12 ensures that the child lock lever 4 is automatically pivoted into the closer angular proximity child lock on end position.