Electric drive unit for closing and / or opening a motor vehicle lock

Abstract

Electric drive unit for closing and / or opening a motor vehicle lock, in particular a motor vehicle door lock, with an actuating unit for actuating the motor vehicle lock, comprising at least one actuating element (10), with an electric motor (4) and a downstream gearbox provided for actuating the actuating unit, and wherein the gearbox is designed with at least one drive wheel (6) and at least one driven wheel (7, 8), characterized in that the drive wheel (6) is equipped with different tooth segments (16, 17) which, depending on the angle of rotation (Δ, Δ), engage with the driven wheel (7) or different driven wheels (7, 8) during its rotation.

Description

The invention relates to an electric drive unit for closing and / or opening a motor vehicle lock, in particular a motor vehicle door lock, having an actuating unit for actuating the motor vehicle lock, having an electric motor and a downstream transmission which are provided for acting on the actuating unit, wherein the transmission is formed with at least one drive wheel and one driven wheel, and wherein at least one wheel has a toothed segment.Electric drive units for closing and / or opening a motor vehicle lock are generally known from DE 10 2015 107 955 A1. In addition to motor vehicle door locks, motor vehicle seat back locks or also motor vehicle fuel filler door locks can in principle also be opened and / or closed with such drive units. Motor vehicle door locks may also include motor vehicle tailgate locks, motor vehicle front hood locks, etc.In the prior art according to DE 10 2015 107 955 A1, a cable pull is implemented as a transmission element connected upstream of the closing lever or opening lever. In the present case, an external actuating lever is used as the opening lever or closing lever. The transmission used is a spur gear transmission which has a pinion and a gearwheel. In addition, an adjusting element designed as a linear adjusting spindle is realized, which engages in a central hollow bore of the gearwheel, so that in this way rotational movements of the gearwheel can be converted into corresponding linear movements of the adjusting element or of the linear adjusting spindle.The linear movements of the adjusting element are transmitted to the outer actuating lever by the transmission element or the cable pull connected upstream thereof. As a result, the external actuating lever is acted upon overall and can thus ensure that the associated motor vehicle lock is pulled closed or opened. This has in principle proved successful.The further prior art according to EP 1 614 840 A2 relates to a closing drive which has a motor-movable lever pair. The pair of levers is composed of a main lever and a secondary lever. In this way, different torques can be realized. For this purpose, the motor or electric motor operates on a gear which drives a control cam of a worm wheel with the aid of a downstream worm.In the generic prior art according to JPH03172486 A, a closing mechanism is used which can be moved into a closing and open position via a drive. The drive is composed of an electric motor and a transmission of at least drive wheel and driven wheel. The output gear is formed in an arc shape with a toothed segment. In order to reverse the drive unit, the electric motor must be acted upon in the opposite direction in comparison to the drive direction.The prior art has proven itself in principle, but is increasingly limited when considering the times for an actuation cycle, i.e. the time required to pull the drive unit or the associated motor vehicle lock closed, for example, and to perform a subsequent reset movement. The same applies to the case in which the motor vehicle lock acted upon by means of the drive unit is opened and subsequently reset. Such actuation cycles and the times associated therewith are sensitive with regard to comfort. In fact, improvements are increasingly demanded at this point. In addition, the installation space available for such electric drive units is reduced more and more, so that particularly compact embodiments are required. The invention seeks to provide a remedy here overall.The invention is based on the technical problem of further developing an electric drive unit of the construction described at the beginning in such a way that the cycle times for one actuation cycle are reduced. In addition, a particularly compact and cost-effective configuration is sought.To solve this technical problem, an electric drive unit of the generic type for closing and / or opening a motor vehicle lock is characterized within the scope of the invention in that the drive wheel is equipped with different tooth segments which, during its rotation, engage with the output wheel or different output wheels depending on the angle of rotation.Within the scope of the invention, the drive wheel is firstly equipped with different toothed segments. These varying tooth segments can differ from one another in that, for example, teeth of different sizes or different shapes are realized. As a rule, however, the different toothed segments of the drive wheel are formed with identical teeth. The toothed segments are consequently distinguished by the angle of rotation. This means that the toothed segments of the drive wheel usually cover predominantly mutually complementary rotational angles of the drive wheel. In this case, it is usual to work with angles of rotation in the range of 120° / 240°. That is, one toothed segment of the drive wheel extends over a rotation angle of 120°, while the other toothed segment and the one which differs therefrom covers the remaining rotation angle of 240° of the drive wheel. This covers the entire full circle of 360°, which corresponds to one revolution of the drive wheel.In order to realize this in detail, the toothed segments of the drive wheel describe different radii in comparison to a common axis. The design is made such that a 240° segment without teeth corresponds to the 120° tooth segment at the corresponding radius. The different 240° toothed segment equipped with a radius differing from that of the other is consequently coupled to an associated 120° segment without teeth.Of course, the different toothed segments can also be provided in a different division on the drive wheel. Thus, a division of the toothed segments over 180° in each case is also within the scope of the invention. As a rule, however, the two toothed segments can be divided at least in the angular range 100° / 260° to 180° / 180°, wherein the division 120° / 240° already mentioned above is particularly preferred.By recourse to the different toothed segments and the different radii realized in this context in comparison to the common axis, the design can also be made and realized overall in such a way that the different toothed segments of the drive wheel correspond to the output wheel or the output wheels at different transmission ratios. In this way, an associated complete actuation cycle, i.e. the closing and resetting or the opening and resetting can be realized and implemented with desired and different transmission ratios. For example, it is conceivable to implement the closing or opening with a relatively small transmission ratio and consequently a low speed of the actuating element acted upon by the output wheel. In contrast, the restoring movement is generally realized with a high transmission ratio and accordingly rapidly on the part of the actuating element. In this way, the time until such an actuation cycle is completed can be significantly reduced overall in comparison with the prior art, so that a significant improvement in comfort is observed.In general, the design is additionally made such that when the different toothed segments of the drive wheel change engagement with the driven wheel or the plurality of driven wheels, the direction of rotation of the relevant driven wheel changes at the same time. In this way, there is the further possibility that the electric motor acts unidirectionally on the transmission for the complete actuation cycle, i.e. closing and resetting or opening and resetting. This once again reduces the time for the entire actuation cycle, because the electric motor is acted upon unidirectionally for the complete actuation cycle, i.e. closing and resetting or opening and resetting, i.e. runs in a single rotational direction. In addition, the drive wheel usually completes a complete revolution corresponding to 360°.During this process, the electric motor ensures via the transmission that, for example, the motor vehicle lock acted upon by it or the actuating element is acted upon for tightening. To this end, the engagement between the first toothed segment of the drive wheel and the driven wheel or one of the driven wheels corresponds. As soon as the electric motor has applied the relevant first toothed segment for tightening over its entire angle of rotation of 240°, for example, the second toothed segment which then comes into engagement with the output wheel ensures during the complementary angle of rotation of 120° in the example the restoring movement or the restoring which is faster in comparison therewith. This simultaneously leads to a change in the direction of rotation of the relevant output wheel or a further other output wheel engages with the drive wheel. This will be explained in more detail below with reference to the exemplary embodiment.In detail, the design is made for this purpose such that the two different toothed segments of the drive wheel can span a common plane. In this case, the toothed segments of the drive wheel arranged in the common plane define a preferably radially extending engagement slot. The driven wheel can enter into this engagement slot. In this way, in conjunction with the respective rotational angles without gearwheels, there is, without any constraint, the possibility that the (single) output wheel in question first engages with the one first toothed segment of the drive wheel and then with the other second toothed segment.However, it is also possible for the two toothed segments of the drive wheel to describe two planes parallel to one another. In this context, the further design is made such that each toothed segment of the drive wheel, depending on its angle of rotation, alternately engages with the respective driven wheel located in the associated plane. In this case, two driven wheels are generally provided, namely in each case one driven wheel in the associated plane of the first or second toothed segment of the drive wheel. In this case, the first toothed segment of the drive wheel meshes, for example, with the first output wheel located in the same plane during the relevant angle of rotation. In contrast, the second toothed segment of the drive wheel meshes with the second driven wheel as soon as the angle of rotation of the first toothed segment has been completed by the drive wheel. At the same time, the rotational direction of the relevant output wheel, in the present case the second output wheel, again changes at this point in comparison to the first output wheel.As a result, an electric drive unit for closing and / or opening a motor vehicle lock is provided, which has a particularly compact and small-scale construction. This can be attributed in essence to the fact that the transmission is equipped at this point with a special drive wheel which has different toothed segments. During a (single) revolution of the drive wheel, the toothed segments engage with the one or the different driven wheels, generally first the first driven wheel and then the second driven wheel, depending on the angle of rotation. As a result, the electric motor can be acted upon unidirectionally for the complete actuation cycle.In conjunction with the compact construction, a particularly short cycle time is observed in this way and particularly advantageously for the relevant actuation cycle. This means that, while the actual process of closing or opening is carried out according to the invention with a comparable time as in the prior art, the restoring process into a neutral position or original position is significantly accelerated in contrast. As a result, the total time required for the actuation cycle is also less than in the prior art. The essential advantages can be seen here.The invention is explained in more detail below with reference to drawings which represent a total of three exemplary embodiments of the invention; it shows: FIG. 1 shows a motor vehicle door lock according to the invention schematically with an associated drive unit for closing or opening the motor vehicle lock, FIG. 2 shows the electric drive unit in a detailed view, FIGS. 3A and 3B show the transmission in a first embodiment variant during a closing process (FIG. 3A ) and a restoring process (FIG. 3B ), FIGS. 4A and 4B show a second variant of the exemplary embodiment according to FIGS. 3A and 3B, again FIG. 4A shows a closing process and FIG. 4B shows the associated restoring process, and FIGS. 5A and 5B show a further third exemplary embodiment of the invention, again the closing process in FIG. 5A and an associated resetting process in FIG. 5B.FIG. 1 shows a motor vehicle door lock which firstly has a locking mechanism consisting of a rotary latch 1 and associated pawl 2 on one side and in its basic features. The locking mechanism is mounted in a lock case 3, which is only indicated in FIG. 1 and is not completely shown. In addition, an electric drive unit is realized which, as shown in FIG. 2, has an electric motor 4 and a downstream transmission.An actuating unit is acted upon by means of the transmission. The actuating unit comprises at least one actuating element 10. For this purpose, the gear mechanism operates on a transmission element 9 connected upstream of the actuating element 10, which transmission element is designed as a linear actuating element or cable pull as shown in FIG. 2. With the aid of the transmission element 9, rotary movements of the transmission on the output side are converted into linear movements of the transmission element 9, which in turn act linearly on the actuating element 10, as is indicated by corresponding arrows in FIG. 1. For this purpose, the electric motor 4 operates via a gearwheel 5 arranged on the output side of its output shaft or else a worm wheel on a drive wheel 6 of the transmission, which meshes with a single output wheel 7 in the variant according to FIGS. 3A and 3B or engages with two output wheels 7, 8 according to the exemplary embodiments in FIGS. 4A to 5B, as will be explained in more detail below.The actuating element 10 of the actuating unit can be acted upon to the left, corresponding to the arrow direction ZZ (closing), with the aid of the drive unit and the transmission element 9 and reset by dashed lines. In addition, the actuating element 10 can be moved to the right in the direction EÖ (electrical opening) and can be reset again in the opposite direction (dashed line). Both the electrical opening and resetting and the closing and resetting are each carried out with one revolution or 360° rotation of a drive wheel 6.For closing the motor vehicle lock or the locking mechanism shown, the actuating element 10 operates in the closing direction ZZ on a closing lever 11 which is rotatably mounted in the lock case or lock housing 3 and which in turn acts on the rotary latch 1 such that it performs a counterclockwise movement indicated here about its axis 13. A locking bolt which has been captured beforehand and is not explicitly shown is pulled more and more into the locking mechanism 1, 2 during this process. The associated motor vehicle door, not shown, is pulled closed.If, on the other hand, an opening process or an electrical opening occurs in the direction EÖ, then the actuating element 10 works in the opposite direction EÖ on an opening lever 12, and the opening lever 12 ensures with a contour 14 that the pawl 2 is lifted from its engagement with the rotary latch 1 in the closed state of the locking mechanism 1, 2 shown in FIG. 1. This includes a clockwise rotation of the pawl 2 about its associated axis 15 as indicated in FIG. 1.The previously described actuating movements of the actuating element 10 and the action on the closing lever 11 or the opening lever 12 are transmitted to the actuating element 10 by corresponding rotary movements of the electric motor 4 via the downstream gear with the transmission element 9 interposed. For this purpose, the transmission is designed specifically according to the invention. In fact, the transmission has the at least one drive wheel 6 and one or two output wheels 7, 8 according to the exemplary embodiment. In fact, in the variant according to FIGS. 3A and 3B, only a single driven wheel 7 is realized. In contrast, the two further embodiment variants according to FIGS. 4A and 4B and 5A, 5B each have two output wheels, namely a first output wheel 7 and a second further output wheel 8.It is clear from a comparative consideration of FIGS. 3A to 5B that not only is at least one wheel of the transmission equipped with a toothed segment 16, 17. The design is rather such that the drive wheel 6 is equipped with the different tooth segments 16, 17. As a result, the drive wheel 6 is in a position according to the invention in which the drive wheel 6 comes into engagement with the driven wheel 7 or the different driven wheels 7, 8 during its rotation depending on the associated angle of rotation. This corresponds to a 360° rotation of the drive wheel 6.Within the scope of the exemplary embodiment, the two different toothed segments 16, 17 of the drive wheel 6 correspond to the driven wheel 7 or the two driven wheels 7, 8 at different transmission ratios. In addition, when the engagement of the different toothed segments 16, 17 with the driven wheel 7 or the two driven wheels 7, 8 is changed, the direction of rotation of the relevant driven wheel 7 or 7, 8 simultaneously changes. The electric motor 4 acts upon the transmission 6, 7, 8 unidirectionally for a complete actuation cycle, that is to say for closing and resetting or for opening and resetting.In addition, the design is made such that the toothed segments 16, 17 of the drive wheel 6 predominantly cover mutually complementary rotational angles α, β. According to the exemplary embodiment, it can be seen that the toothed segment 16 describes approximately an angle α of approximately 240°, which is indicated in FIGS. 3A and 4B and FIG. 5B. In contrast, the toothed segment 17 sweeps over the complementary angle of rotation or angle β from the 120° still remaining. This means that, taken together, the two toothed segments 16, 17 or their associated and covered angles α, β sweep over approximately 360°, which corresponds to a total revolution of the drive wheel 6 (α+β≈350°).It can also be seen that the toothed segments 16, 17 of the drive wheel 6 have different radii R 1 and R 2 in comparison with a common rotational axis 18 of the drive wheel 6. In fact, the toothed segment 16 is equipped with a smaller radius R 1 in comparison with the toothed segment 17, which, in contrast, has an enlarged radius R 2 in comparison with the common axis of rotation 18.In the exemplary embodiment according to FIGS. 3A and 3B, the design is such that the two toothed segments 16, 17 span a common plane. In this way, the two toothed segments 16, 17 of the drive wheel 6 arranged in the common plane define an engagement slot 19. In order that the two toothed segments 16, 17 engage in each case only alternately with the associated output wheel 7 or the two output wheels 7, 8, the complementary angle associated with the corresponding angle α or β is designed in each case without gearwheels. For this reason, the two toothed segments 16, 17 are also only seen over a circular segment, while the region belonging outside the respective angle α or β is recessed or has no gearwheels.The two exemplary embodiments according to FIGS. 4A and 4B and 5A and 5B are distinguished in that the toothed segments 16 and 17 of the drive wheel 6 describe two planes parallel to one another. In fact, the design here is such that the first toothed segment 16 of the drive wheel 6 meshes with or can engage the first driven wheel 7. In contrast, the second toothed segment 17 interacts with the second output wheel 8, and the design is also such that the two toothed segments 16, 17 come into alternate engagement with the associated respective output wheel 7, 8 situated in the same plane.The operation is as follows. If one proceeds from the exemplary embodiment in FIGS. 3A and 3B, then first of all FIG. 3A shows the process of pulling. During tightening, the first toothed segment 16 of the drive wheel 6 is in engagement with the (single) output wheel 7. The drive wheel 6 is set in rotation via the gearwheel 5 and consequently the electric motor 4, in counterclockwise rotations according to the exemplary embodiment in FIG. 3A. Since the output wheel 7 meshes with the toothed segment 16 during the tightening, this counterclockwise rotation of the drive wheel 6 overall results in the output wheel 7 rolling clockwise on the associated toothed segment 16 according to FIG. 3A. This means that during tightening, the rotational movements of the drive wheel 6 on the one hand and of the driven wheel 7 on the other hand are directed opposite to one another. The clockwise rotation of the driven wheel 7 is converted during the closing process into the linear movement ZZ shown in FIG. 1 and ensures the previously already described actuation of the closing lever 11 and ensures that the rotary latch 1 is actuated about its axis 13 in the counterclockwise direction indicated in FIG. 1.As soon as the drive wheel 6 has completed the entire angle or angle of rotation α of 240° associated with the first toothed segment 16 in the example, the rotary latch 1 is pulled closed. It is then necessary to reset the actuating element 10 of the actuating unit so that it is available for a new closing operation. A situation is shown as shown in FIG. 3B. In this case, the driven wheel 7 has disengaged from the first toothed segment 16 and, on the contrary, meshes with the second toothed segment 17 during the continuous rotation of the drive wheel 6 in the counterclockwise direction. The electric motor 4 is still acted upon in one and the same direction of rotation-unidirectionally. The engagement of the driven wheel 7 with the second toothed segment 17 taking into account the angle of rotation or angle β now has the consequence that the direction of rotation of the driven wheel 7 changes.Whereas the driven wheel 7 has previously moved in the clockwise direction during the tightening process in FIG. 3A, the interaction between the second toothed segment 17 of the drive wheel 6 and the driven wheel 7 now has the result that the latter performs a counterclockwise rotation. Consequently, in the restoring process in FIG. 3B, the drive wheel 6 and the (single) output wheel 7 move in the same direction, namely in the common counterclockwise direction. In addition, the increased transmission ratio between the drive wheel 6 and the driven wheel 7 realized in this connection ensures that the movement of the driven wheel 7 is accelerated during the process of resetting, and consequently the resetting process takes place more quickly overall than is the case for the previously described closing process.The two further exemplary embodiments according to FIGS. 4A, 4B and 5A, 5B function in a comparable manner. FIGS. 4A and 5A each show the process of pulling. In this context, the electric motor 4 again ensures that the drive wheel 6 is acted upon in the counterclockwise direction indicated. As a result, first toothed segment 16 again meshes with output wheel 7 in the exemplary embodiment. The output wheel 7 is in the present case the first output wheel 7. Since the output wheel 7 is connected to the second output wheel 8 in a meshing manner at the same time, the clockwise rotation carried out by the first output wheel 7 leads, as a result of the action of the first toothed segment 16, to the second output wheel 8 rotating in the counterclockwise direction indicated in FIGS. 4A and 5A. The closing process in FIGS. 4A and 5A is continued until the first toothed segment 16 has rolled off overall on the output wheel or first output wheel 7 in the example case, taking into account the associated angle or angle of rotation α of 240°. The tightening corresponds to this.If the drive wheel 6 is now acted upon unchanged counterclockwise by means of the electric motor 4, as is shown in FIGS. 4B and 5B, and in this case the region beyond the angle α of the first toothed segment without gearwheels is located opposite the first toothed wheel 7, the second toothed segment 17 of the drive wheel 6 can mesh with the second driven wheel 8 and come into engagement. This is illustrated in FIGS. 4B and 5B. Since the drive wheel 6 continues its counterclockwise movement unchanged and the second toothed segment 17 meshes with the second driven wheel 8 in this case and during the resetting, the second driven wheel 8 now performs a clockwise movement illustrated in FIGS. 4B and 5B.The clockwise movement of the second driven gear 8 causes the first driven gear 7 to move counterclockwise as shown in FIGS. 4B and 5B through the meshing connection with the first driven gear 7. This means that the process of resetting again corresponds to both the drive wheel 6 and the driven wheel 7 or the first driven wheel 7 being pivoted jointly and in a corresponding manner in the counterclockwise direction.As a result, the process of closing or resetting in FIG. 1 occurs again, as has already been illustrated with reference to the exemplary embodiment according to FIGS. 3A and 3B. Alternatively, the electric drive unit can of course also be used for electric opening EÖ without structural changes, in that the relevant output wheel 7 or the first output wheel 7 acts via the transmission element 9 on the actuating element 10 accordingly, as is indicated in FIG. 1 by the arrows reproduced there.The toothed segments 16, 17 and wheels 6, 7, 8 shown can have toothed wheels of any desired design. Involute tooth arrangements, cycloid tooth arrangements, etc. A central or eccentric engagement is also possible here.List of reference characters1 Rotary latch 2 Pawl 3 Lock case / lock housing 4 Electric motor 5 Gearwheel 6 Drive wheel 7 Driven wheel / first driven wheel 8 Driven wheel / second driven wheel 9 Transmission element 10 Actuating element 11 Closing lever 12 Opening lever 13 Axis 14 Contour 15 Axis 16 Toothed segment / first toothed segment 17 Toothed segment / second toothed segment 18 Axis of rotation 19 Engagement slot EO direction / opposite direction / electrical opening R 1 Radius R 2 Radius ZZ Arrow direction (closing) / closing direction / linear movement α Angle of rotation / angle β Angle of rotation / angle

Claims

Electric drive unit for closing and / or opening a motor vehicle lock, in particular a motor vehicle door lock, having an actuating unit for actuating the motor vehicle lock, which actuating unit comprises at least one actuating element (10), having an electric motor (4) and a downstream transmission which is provided for acting on the actuating unit, and wherein the transmission is formed with at least one drive wheel (6) and at least one driven wheel (7, 8), characterized in that the drive wheel (6) is equipped with different tooth segments (16, 17) which, during its rotation, engage with the driven wheel (7) or with different driven wheels (7, 8) depending on the angle of rotation (α, β).Drive unit according to Claim 1, characterized in that the different toothed segments (16, 17) of the drive wheel (6) correspond to the driven wheel (7) or the driven wheels (7, 8) at different transmission ratios.Drive unit according to Claim 1 or 2, characterized in that, when the engagement of the various toothed segments (16, 17) with the output wheel (7) or the output wheels (7, 8) is changed, the direction of rotation of the relevant output wheel (7, 8) simultaneously changes.Drive unit according to one of Claims 1 to 3, characterized in that the electric motor (4) acts unidirectionally on the transmission (6, 7, 8) for a complete actuation cycle, that is to say closing and resetting or opening and resetting.Drive unit according to one of Claims 1 to 4, characterized in that the toothed segments (16, 17) of the drive wheel (6) predominantly cover mutually complementary rotational angles (α, β).Drive unit according to one of Claims 1 to 5, characterized in that the toothed segments (16, 17) of the drive wheel (6) describe different radii (R 1, R 2) in comparison with a common axis (18) of the drive wheel (6).Drive unit according to one of Claims 1 to 6, characterized in that the toothed segments (16, 17) of the drive wheel (6) span a common plane.Drive unit according to Claim 7, characterized in that the toothed segments (16, 17) of the drive wheel (6) arranged in the common plane define a preferably radially extending engagement slot (19) for the driven wheel (7, 8).Drive unit according to one of Claims 1 to 6, characterized in that the toothed segments (16, 17) of the drive wheel (6) describe two planes parallel to one another.Drive unit according to Claim 9, characterized in that each toothed segment (16, 17) of the drive wheel (6) comes into alternate engagement with the respective output wheel (7, 8) located in the associated plane, depending on the angle of rotation (α, β) thereof.

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