MOTOR VEHICLE DOOR LATCH

Abstract

A motor vehicle door latch, in particular a servo latch, which is equipped with a locking mechanism including of a catch and a pawl. Furthermore, a spindle drive with a motor, spindle and spindle nut located thereon is executed at least to close the locking mechanism. The spindle nut impinges the catch at least in the closure direction via a closure lever. The closure lever is simultaneously formed as an opening lever to open the locking mechanism and consequently as a combined closure/opening lever. The combined closure/opening lever impinges either the catch in a closing direction or the pawl in an opening direction dependent on the actuating direction of the spindle drive.

Claims

1. A motor vehicle door latch, in particular a servo latch, comprising: a locking mechanism including a catch (1) and a pawl (2), and a spindle drive with a motor, spindle and a spindle nut located thereon at least to close the locking mechanism, the spindle nut impinging the catch at least in the closure direction via a closure lever, the closure lever being simultaneously formed as an opening lever to open the locking mechanism and consequently as a combined closure/opening lever, the combined closure/opening lever either impinging the catch in a closed direction or the pawl in an open direction according to am actuating direction of the spindle drive.

2. The motor vehicle door latch according to claim 1, wherein the closure/opening lever is formed as a pivoting lever located coaxially to the catch.

3. The motor vehicle door latch according to claim 1, wherein the closure/opening lever is connected to the spindle nut on a rotating joint with one end and is pivotably located coaxially with the catch at the other end.

4. The motor vehicle door latch according to claim 1, wherein the closure/opening lever (10, 11) is equipped with a stop element pivotably located thereon which, dependent on the actuating direction of the spindle drive either interacts with the pawl or a stop on the catch.

5. The motor vehicle door latch according to claim 4, wherein the stop element is pivoted starting from a neutral position of the spindle drive with the aid of a static conducting element according to the actuating direction of the spindle drive either in the direction of the pawl or in the direction of the catch around its axis on the closure/opening lever.

6. The motor vehicle door latch according to claim 1, wherein a neutral position of the spindle drive is only assumed in a spring-assisted manner.

7. The motor vehicle door latch according to claim 6, wherein the spindle drive is equipped with at least one opening/resetting spring to assume the neutral position at least following an opening process of the locking mechanism.

8. The motor vehicle door latch according to claim 7, wherein the opening/resetting spring is arranged between a stop on the motor side and a stop on the spindle nut side.

9. The motor vehicle door latch according to claim 1, wherein additionally a closure/resetting spring is provided for to assume a neutral position at least after a closure process of the locking mechanism.

10. The motor vehicle door latch according to claim 9, wherein the opening/resetting spring is equipped with a larger spring constant than the closure/resetting spring, for example demonstrates a spring constant which is at least two to three times as large.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Hereinafter, the invention is explained in further detail on the basis of a sketch which only depicts an execution example. It shows:

[0029] FIG. 1 the motor vehicle door latch according to the invention,

[0030] FIG. 2 an excerpt from FIG. 1 reduced to the spindle drive and the locking mechanism in the neutral position of the spindle drive,

[0031] FIG. 3 the object according to FIG. 2 in an opening process,

[0032] FIG. 4 the object according to FIG. 2 at the start of a closure process and

[0033] FIG. 5 the complete closure process following the functional representation in FIG. 4.

DETAILED DESCRIPTION OF AN EXEMPLARY EXECUTION

[0034] In the figures a motor vehicle door latch is depicted which involves a servo latch which is equipped with a drive for this purpose. The drive works on a locking mechanism 1, 2 comprising a catch 1 and a pawl 2. The catch 1 is pivotably located around an axis 3. A similar scenario applies to the pawl 2 which accomplishes or can accomplish rotation around an axis 4. Both axes 3, 4 are defined by respective bolts or joint bolts which are anchored in a latch case only depicted in FIG. 2 or a latch sheet 5.

[0035] The drive formed as a spindle drive 6, 7, 8, 9 pertains to the basic construction. In fact, the spindle drive 6, 7, 8, 9 according to the execution example has a (single) motor 6, a gearwheel 7, a spindle 8 and a spindle nut 9 located on the spindle 8. On the basis of FIG. 1, it can be ascertained that the motor 6 and the spindle 8 are arranged in parallel and in the same lengthwise extension for the purpose of compact construction.

[0036] On the basis of the principle sketch according to FIG. 2, it is furthermore recognized that the motor 6 designed as an electromotor is equipped with an output shaft which demonstrates an output gearwheel. The output gearwheel of the (only) motor 6 is combed with a gearbox wheel 7. Thus, the output gearwheel and the gearwheel 7 in the execution example form a reduction gearbox, which of course is only an example and is not compulsory.

[0037] The gearwheel 7 is connected to the spindle or threaded spindle 8 in a torque-proof manner. Thus, rotational movements of the motor or electromotor 6 can be transferred via the gearwheel 7 to the spindle 8. Rotations of the spindle 8 now lead to the spindle nut 9 located on the spindle 8 being able to execute the linear movements depicted in FIG. 2. The neutral position or park position of the spindle drive 6, 7, 8, 9 is depicted in FIG. 2. Starting from this neutral position, the spindle drive 6, 7, 8, 9 both ensures that the locking mechanism 1, 2 can be opened as depicted in FIG. 3 and that the locking mechanism 1, 2 can also be closed with the aid of the spindle drive 6, 7, 8, 9 as depicted in FIGS. 4 and 5.

[0038] A movement of the spindle drive 6, 7, 8, 9 or the spindle nut 9 starting from the neutral position according to FIG. 2 to the right corresponds to the opening process of the locking mechanism 1, 2, as made clear in a comparison of FIGS. 2 and 3. An arrow in FIG. 3 depicts this. A (first) actuating direction of the spindle drive 6, 7, 8, 9 corresponds to this.

[0039] In addition to this opening process however, a closure process of the locking mechanism 1, 2 with the aid of the spindle drive 6, 7, 8, 9 can also be depicted. A movement of the spindle nut 9 to the left starting from the neutral position corresponds to this. This is depicted in FIGS. 4 and 5 and is assisted by a relevant movement arrow which depicts the other (second) actuating direction of the spindle drive 6, 7, 8, 9. FIG. 5 finally shows the complete closure process. The closure process of the locking mechanism 1, 2 depicted in FIGS. 4 and 5 occurs again starting from the neutral position according to FIG. 2.

[0040] The spindle nut 9 located on the spindle 8 impinges the catch 1 via a closure lever 10, 11 for this purpose, at least in the closure direction or the pawl 2 at least in the opening direction. In fact, the relevant closure lever 10, 11 according to the invention is one which is not only suitable and designed as an opening lever 10, 11 to close the locking mechanism 1, 2 but also opens the locking mechanism 1, 2. Consequently, the relevant closure lever 10, 11 or opening lever 10, 11 is designed as a combined closure/opening lever 10, 11 according to the invention.

[0041] The combined closure/opening lever 10, 11 impinges either the catch 1 closing or the pawl 2 opening dependent on the actuating direction of the spindle drive 6, 7, 8, 9. i.e. the sole motor 6 of the spindle drive 6, 7, 8, 9 ensures that the spindle drive 6, 7, 8, 9 is either moved in the first actuating direction or the second actuating direction. According to this actuating direction, the spindle nut 10 impinges a single and combined closure/opening lever 10, 11, which is responsible both for opening the locking mechanism 1, 2 and also for closing the locking mechanism 1, 2. That depends on the actuating direction of the spindle drive 6, 7, 8, 9.

[0042] In fact, in the execution example the design is such that the combined (sole) closure/opening lever 10, 11 is formed coaxially to the pivoting lever 10, 11 located on the catch 1 or demonstrates such. i.e. the combined closure/opening lever 10, 11 uses the axis 3 concurring with the catch 1 for its pivoting movements.

[0043] To this end, the combined (sole) closure/opening lever 10, 11 is connected to the spindle nut 9 with a rotating joint at one end. Its other end is pivotably located on the common axis 3 with the catch 1. Furthermore, it is recognized on the basis of the figures that the relevant combined and sole closure/opening lever 10, 11 is a flat lever 10 or the closure/opening lever 10, 11 demonstrates such a flat lever or a general lever 10. The width extension of the relevant flat lever 10 is thus oriented in the actuating direction or coincides with the drawing plane. Thus, any forces transmitted with the aid of the spindle nut 9 on the closure/opening lever 10, 11 touch in the respective actuating direction along the wide side of the flat lever 10 which is consequently especially stiff in this force direction. Thus, great forces can be transmitted, whereby closure forces of up to 1000 Newtons are possible, for example.

[0044] Such great closure forces can be transmitted with the aid of the described spindle drive 6, 7, 8, 9 onto the locking mechanism 1, 2 or the catch 1 and are especially advantageous in view of the fact that nowadays, for example, rubber door seals accumulate especially great resetting forces during such a closure process for convenience reasons and to minimize vehicle noises as far as possible.

[0045] The closure/opening lever 10, 11 comprises the actual lever or flat lever 10 and a stop element 11 pivotably located on the lever 10. Dependent on the actuating direction of the spindle drive 6, 7, 8, 9, the stop element 11 interacts either with the pawl 2 or with a stop 12 on the catch 1. In fact, the stop element 11 is pivoted with the aid of a static conducting element 13 for this purpose. The static conducting element 13 may be a conducting bolt 13 which is connected to a latch cover or a latch housing sealing the latch case 5 on the upper side or which constitutes a component thereof, which is not shown in greater detail however.

[0046] By the conducting of the stop element 11 and its pivotable location on the lever or flat lever 10 with the definition of a pertaining axis or rotational axis 14 the relevant stop element 11 either pivots in the direction of the pawl 2 or in the direction of the catch 1 around the relevant axis 14 on the closure/opening lever 10, 11 or the flat lever 10 starting from the neutral position of the spindle drive 6, 7, 8, 9 according to FIG. 2 pivots with the aid of the conducting element or conducting bolt 13 according to the actuating direction of the spindle drive 6, 7, 8, 9. This is recognized in the transition from FIG. 2 to FIG. 3 or in the transition from FIG. 2 to FIG. 4.

[0047] In fact, the transition from the neutral position according to FIG. 2 to FIG. 3 corresponds to the spindle drive 6, 7, 8, 9 being impinged to open the locking mechanism 1, 2 and hereby the spindle nut 9 moving to the right as depicted in FIG. 3. The consequence of this is that the combined closure/opening lever 10, 11 is pivoted in the clockwise direction indicated in FIG. 3 in the transition from FIG. 2 to FIG. 3. Thus, the stop element 11 distanced from the pawl 2 in the neutral position becomes adjacent to the pawl 2. For this purpose, the stop element 11 possesses a relevant stop surface 11a. In addition to this stop surface 11a interacting with the pawl 2 during the opening process, the stop element 11 also has a further stop surface 11b opposite to the axis 14 which is viewed in further detail below.

[0048] The opening process now results in the relevant stop surface 11a of the stop element 11 moving against the pawl 2. At the same time, the stop element 11 experiences the described pivoting movement in a clockwise direction around its axis 14. Because in the relevant transition from FIG. 2 to FIG. 3 the stop element 11 is moved along the conducting bolt 13 and pivoted around its axis 14 in the execution example in a clockwise direction in the direction of the pawl 2.

[0049] Because the stop element 11 moves against the pawl 2 with its stop surface 11a at the abaxial end, the pawl 2 is lifted from its engagement into the catch 1. Thus, the pawl 2 executes the clockwise direction movement around its axis 4 indicated in FIG. 3. The pawl 2 previously engaged in a main ratchet 15. The main ratchet position of the locking mechanism 1, 2 as shown in FIG. 2 corresponds to this. In addition, the locking mechanism 1, 2 can also assume a pre-ratchet position as depicted in FIG. 4. Then the pawl 2 engages into a pre-ratchet 16.

[0050] In addition to the opening process outlined and consequently the transition of the spindle drive 6, 7, 8, 9 from the neutral position according to FIG. 2 to the opening position of the locking mechanism 1, 2 in FIG. 3, the spindle drive 6, 7, 8, 9 can also be impinged in such a way that the relevant locking mechanism 1, 2 is closed. The closing process depicted in FIGS. 4 and 5 and the ultimately attained closure position according to FIG. 5 corresponds to this.

[0051] In order to accomplish such a closure process, the spindle drive 6, 7, 8, 9 is impinged in the second actuating direction, in the present case in the transition from the neutral position according to FIG. 2 at the start of the closure process according to FIG. 4 in such a way that the spindle nut 9 is moved to the left. As a consequence hereof, the combined closure/opening lever 10, 11 is pivoted around its axis 3 in an anti-clockwise direction starting from the neutral position according to FIG. 2. As for the opening process, the stop element 11 also slides along the static conducting bolt 13 in the closure process now to be described. Thus, the stop element 11 is pivoted in the direction of the catch 1. A pivoting movement of the stop element 11 around its axis 14 in an anti-clockwise direction during transition from the neutral position according to FIG. 2 to the start of the closure position according to the illustration in FIG. 4 corresponds to this.

[0052] Thus, the stop element 11 on the lever or flat lever 10 is pivoted around its axis 14 in the direction of the catch 1 with the aid of the conducting bolt 13. Thus, the stop element 11 becomes adjacent to the stop 12 of the catch 1 with its other stop surface 11b, which is fitted onto the catch 1 on the other side of the pre-ratchet 16. If the spindle nut 9 is now moved further to the left starting from this position according to FIG. 4 at the start of the closure process, the stop element 11 carries the catch 1 along. The locking mechanism 1, 2 is in the pre-ratchet position in the illustration according to FIG. 4 and at the start of the closure process. The pawl 2 is consequently engaged into the pre-ratchet 16 of the catch 1. The advancing closure process during transition from FIG. 4 to FIG. 5 now leads to the catch 1 being pivoted around its axis 3 in the anti-clockwise direction indicated in FIG. 4. Thus, the pawl 2 initially engages into the main ratchet 15.

[0053] Within the scope of the execution example, the locking mechanism 1, 2 is pivoted into an overstroke position as depicted in FIG. 5 which ultimately corresponds to the closure position. In this overstroke position, the pawl 2 is a short distance from the main ratchet 15 and can engage securely. Consequently, after the end of the impingement of the motor 6 the locking mechanism 1, 2 transfers into the main ratchet position as depicted in FIG. 2. At the same time, in this process the spindle nut 9 moves back into the neutral position according to the illustration in FIG. 2. The neutral position according to FIG. 2 is also assumed again following the opening process of the spindle drive 6, 7, 8, 9 illustrated in FIG. 3.

[0054] A total of two springs 17, 18 can ensure assumption of the neutral position according to FIG. 2. The spring 17 is an opening/resetting spring 17 of the spindle drive 6, 7, 8, 9. The opening/resetting spring 17 can ensure that the spindle drive 6, 7, 8, 9 assumes the neutral position according to the illustration in FIG. 2 at least after the opening process of the locking mechanism 1, 2 according to the functional position in FIG. 3.

[0055] In contrast, the other spring 18 designed as an additional closure/resetting spring 18 can ensure that the neutral position of the spindle drive 6, 7, 8, 9 is assumed again at least after a closure process of the locking mechanism 1, 2 according to the functional process in FIGS. 4 and 5. The closure/resetting spring 18 has a considerably lower spring constant than the opening/resetting spring 17. In fact, the spring constant of the opening/resetting spring 17 may be at least two or three times as large as that of the closure/resetting spring 18.

[0056] This circumstance takes account of the fact that the closure/resetting spring 18 only needs to overcome frictional forces of the spindle drive 6, 7, 8, 9 in the transition from the closure position according to FIG. 5 to the neutral position according to FIG. 2. This primarily involves frictional forces between the spindle 8 and the spindle nut 9 located thereon. In contrast, the design of the opening/resetting spring 17 is such that this ensures and can ensure even when the spindle drive 6, 7, 8, 9 has broken down or the motor or electromotor 6 is defective or also where this is increased mechanical resistance that the spindle drive 6, 7, 8, 9 is reset purely mechanically from the opening position according to the illustration in FIG. 3 to the neutral position according to FIG. 2 in any case. This can be especially important to the extent that a closure process subsequent to the opening position according to FIG. 3 and the subsequent opening of the catch 1 wound not be possible otherwise. Because only in the neutral position according to FIG. 2 does the stop element 11 demonstrate the desired distance to the pawl 2 in such a way that it can initially engage into the pre-ratchet 15 and then into the main ratchet 16 in the relevant closure process.

[0057] In detail, the opening/resetting spring 17 according to the illustration in FIG. 1 is arranged between a stop 19 on the motor side and a stop 20 on the spindle nut side. The opening/resetting spring 17 in the execution example is a spiral-shaped coil spring which concentrically surrounds the spindle 8. Furthermore, the opening/resetting spring 17 is at least partly plunged into the gearwheel 7 or a hollow bore in the gearwheel 7 in such a way that the especially compact construction recognized in FIG. 1 is clarified inter alia. In the transition from the neutral position illustrated in FIG. 2 to the opening position according to FIG. 3, the opening/resetting spring 17 is compressed because the stop 20 on the spindle nut side is moved in the direction of the stop 19 on the motor side.

[0058] This is attributable to the fact that in the transition from the functional position in FIG. 2 to FIG. 3 the spindle nut 9 is moved to the right and consequently the stop 20 on the spindle nut side adjacent to the spindle nut 9 reduces its distance to the stop 19 on the motor side. As soon as the stop 20 on the spindle nut side is adjacent to the stop 19 on the motor side the opening movement of the spindle drive 6, 7, 8, 9 ends and the motor vehicle door latch or the spindle drive 6, 7, 8, 9 and consequently the locking mechanism 1, 2 has reached the opening position according to FIG. 3. In the opening position according to FIG. 3, the pawl 2 is lifted from its engagement with the catch 1. Consequently, the catch 1 can subsequently open in a spring-assisted manner and releases a previously caught locking bolt. A pertaining motor vehicle door is also released.

[0059] Starting from the opening position according to FIG. 3, the electromotor 6 can now be switched off. As the opening/resetting spring 17 has previously been compressed in the opening position according to FIG. 3, the absent impingement of the electromotor 6 ensures that the opening/resetting spring 17 is relaxed. This process is not influenced by the closure/resetting spring 18 because it possesses a much lower spring constant as described. The relaxed position of the opening/resetting spring 17 corresponds to the neutral position according to FIG. 2 which is consequently assumed purely mechanically by the spindle drive 6, 7, 8, 9. In this neutral position according to FIG. 2 the pawl 2 is also located in its starting position or neutral position. Consequently, the pawl 2 can easily engage into the catch 1 starting from the completely open position of the catch 1 depicted in FIG. 3 in dot dashes subsequently in a closure process.

[0060] If the spindle drive 6, 7, 8, 9 now completes a closure process in the transition to FIGS. 4 and 5 from the neutral position according to FIG. 2, the spindle nut 9 moves away from the stop 20 on the spindle nut side which it is adjacent to in the previously described opening process of the locking mechanism 1, 2. This is recognized in the transition from FIG. 2 to FIG. 4. Consequently, in the aforementioned closure process according to the illustration in FIGS. 4 and 5 only the closure/resetting spring 18 is tensioned. The closure/resetting spring 18 is a spiral spring. The closure/resetting spring 18 is connected to the end side of the spindle 8 in a torque-proof manner. Thus, rotations of the spindle 8 lead directly to the closure/resetting spring 18 being tensioned. Due to the considerably lower spring constant of the closure/resetting spring 18 compared to that of the opening/resetting spring 17, relevantly constructed spring forces have no impact with regard to the closure/resetting spring 18 on the previously described opening process and the resetting movement of the closure/opening lever 10, 11.

[0061] In contrast, the closure/resetting spring 18 starting from the closure position according to FIG. 5 ensures that the closure/opening lever 10, 11 is reset to its neutral position according to FIG. 2 when the drive ceases on the part of the electromotor 6. As the opening/resetting spring 17 remains unaffected overall, the closure/resetting spring 18 being sufficient that any frictional forces of the spindle drive 6, 7, 8, 9 are overcome.