Patent Application
20080018283
This application is a continuation-in-part of International Application No. PCT/EP2006/000221.
1. Field of the Invention
This invention relates to a drive arrangement for motorized positioning of a functional element in a motor vehicle having a drive motor by which the functional element can be moved by a motor in two positioning directions, the drive motor being coupled via a first drive train and a second drive train to the functional element and the driving force being transmitted at the same time via both drive trains in the motorized movement of the functional element in at least one positioning direction.
2. Description of Related Art
The concept “drive arrangement” should be understood comprehensively here. The scope of application of the functional element under consideration comprises all areas of a motor vehicle in which there is motorized positioning of a functional element. Accordingly, the aforementioned functional element can be a tailgate, hood or cargo space hatch which can be positioned by a motor, as well as the trunk lid of a motor vehicle which can be positioning by a motor. Other examples of a functional element are all types of side doors which can be positioned by a motor, especially sliding doors which can be positioned by a motor. Other functional elements are convertible roofs, large-area roof windows or the like which can be positioned by a motor. Primarily the area of a tailgate of a motor vehicle which can be positioned by a motor is treated below, but should not be understood as limiting.
The known drive arrangement (U.S. Pat. No. 5,531,498) underlying the invention is used for motorized positioning of the “tailgate” in a motor vehicle as the functional element. The drive arrangement has a drive motor by which the tailgate can be moved by a motor in two positioning directions, therefore in the opening direction and in the closing direction. The tailgate here is equipped with two gas compression springs which cause pretensioning of the gate in the opening direction. In this way, a driving force or driving torque can be applied by the drive motor only in the closing direction of the tailgate. In the motorized opening process, it is therefore such that a braking function accrues to the drive motor in any case.
The drive motor is coupled by drive engineering via two drive trains to the tailgate, the driving force or driving torque being transmitted fundamentally at the same time via the two drive trains. Both drive trains act laterally on the tailgate; this counteracts the twisting of the tailgate in its motorized positioning. The drive motor is located essentially centrally on the tailgate, the two drive trains each having a cable-operated speed transforming transmission with a driving cable for transmission of the driving force. This cable-operated speed transforming transmission has advantages especially with respect to noise development in motorized positioning. In any case, durability is limited by the ageing phenomena which are to be expected, especially by unwanted stretching of the drive cable, by which operating reliability is reduced overall. Furthermore, the mechanical structure is comparatively complex.
The object of the invention is to embody and develop the known drive arrangement such that the operating reliability is increased and the mechanical structure is simplified.
The aforementioned object is achieved in a drive arrangement of the initially mentioned type wherein only one of the two drive trains has a cable-operated speed transforming transmission for transmission of the driving force and that the other drive train is made without a cable.
What is important, first of all, is the finding that special advantages are obtainable when the two drive trains are of mechanically different types. In particular, it is provided that only one of the two drive trains has a cable-operated speed transforming transmission for transmission of the driving force and that the correspondingly other drive train is made without a cable. Thus, the drive train without the cable can be made exclusively with transmission elements, such as, for example, levers, gear wheels, connecting rods or the like, so that, in any case, this drive train has especially high durability. The correspondingly other drive train can then be made completely or partially as a cable-operated speed transforming transmission.
In one embodiment, the two drive trains each have kinematic couplings which ensure coupling of the respective drive train to the functional element to be positioned. The two kinematic couplings are made essentially identical in an especially preferred embodiment.
The approach in accordance with the invention can be applied especially advantageously to the hatch of a motor vehicle. The term “hatch” comprises all types of the aforementioned gates and covers of a motor vehicle. The use of the term “hatch” should not be interpreted in a restrictive manner.
An optimum arrangement is achieved by an embodiment in which the two kinematic couplings are located on opposite sides of the hatch, the drive motor being located in the immediate vicinity of the kinematic coupling. Drive-engineering “supply” of the second kinematic coupling takes place accordingly via the cable-operated speed transforming transmission of the second drive train.
A further increase of operating reliability is obtained by a clutch being connected between the drive motor and the drive trains, the clutch having a planetary gear which has a sun wheel, ring gear or planet carrier which can be braked for engagement via a brake. Additionally, tolerances which arise for example from stretching of the drive cable can be easily balanced by a spring-loaded tension roller.
In all drive arrangements with a single drive motor which is coupled by drive engineering via two drive trains to the functional element, unilateral tolerances, stretching, deformations and the like generally lead to unwanted changing of the division of the drive force between the two drive trains. In the hatch of the motor vehicle, this inevitably leads to twisting of the hatch. In the extreme case, this limits the operating reliability.
What is important here is the fact that, between the drive motor and the two drive trains, a differential is connected such that, for unilateral tolerances, a uniform power distribution between the two drive trains is ensured. This approach can be used for all conceivable embodiments of the two drive trains, regardless of whether, as described above, a cable-operated speed transforming transmission is used or not.
Other advantages, features, properties and aspects of this invention will become apparent from the following description with reference to the accompany the drawings.
The preferred embodiments shown in FIGS. 1 to 7 relate to the motorized positioning of the functional element “tailgate” in a motor vehicle. It should not be interpreted in a restrictive manner. First of all, a few statements relating to the functional element 1 in general will be given below.
The motor vehicle shown only in part in
The driving force is transmitted in the motorized movement of the functional element 1 at least in one positioning direction at the same time via the two drive trains 3, 4. In the embodiment shown in
In an especially preferred configuration, a driving force for positioning of the functional element 1 can be transmitted in two directions via the first drive train 3. This is, for example, the case when the first drive train 3 has exclusively gearwheel speed transforming transmissions, worm-pinion speed transforming transmissions or the like. This is shown in
In another preferred embodiment, the first drive train 3 has a first kinematic coupling 7 and the second drive train 4 has a second kinematic coupling 8, the two kinematic couplings 7, 8 ensuring the coupling of the respective drive train 3, 4 to the functional element 1 via drive engineering. For the preferred embodiment shown in
In the embodiment shown in
In one especially preferred configuration, the drive motor 2 is located in the immediate vicinity of the first kinematic coupling 7. Here, the two kinematic couplings 7, 8, as shown in
In the above described drive arrangement shown in
The aforementioned delivery of force via two drive trains 3, 4 is especially advantageous for the hatch 1 of a motor vehicle. As is shown in
It is pointed out that, in the embodiment shown in
Especially against the background of the danger of twisting of the hatch 1, it is preferably provided that the two kinematic couplings 7, 8 are coupled essentially symmetrically to the hatch 1 in terms of drive engineering. In this connection, it is preferably such that the two kinematic couplings 7, 8 act on the hatch 1 on its respective opposite sides and are, accordingly, located laterally. In the preferred embodiment shown in
In the above described preferred configuration, the drive motor 2, together with the first kinematic coupling 7, is located on one side and the second kinematic coupling 8 is accordingly located on the opposite side. Here, it is provided, for example, that the cable-operated speed transforming transmission 5 bridges the region of the rear roof frame or the like over a straight segment. As described above, deflection of the drive cable 6 can be eliminated.
It has already been pointed out that the kinematic couplings 7, 8 are each made as a connecting rod, speed transforming transmission. For this purpose, first of all, the first kinematic coupling 7 has a first positioning element 12 which can be pivoted around a first positioning element axis 11 and a first connecting rod 13. Accordingly, the second kinematic coupling 8 is equipped with a second positioning element 15 which can be pivoted around a second positioning element axis 14 and with a second connecting rod 16. Both connecting rods 13, 16 are, on the one hand, coupled eccentrically with regard to the respective positioning element axis 11, 14 relative to the respective positioning element 12, 15, and on the other hand, relative to the hatch 1. As explained above, the two kinematic couplings 7, 8 are made essentially identical and are arranged in mirror image here.
It should be pointed out that, for implementation of the two kinematic couplings 7, 8, numerous versions are conceivable. For example, as shown in
A series of versions is also possible for implementation of the cable-operated speed transforming transmission 5. In a preferred embodiment, the cable-operated speed transforming transmission 5 has a first cable roller 17 and a second cable roller 18, and the drive cable 6 for drive-engineered coupling of the two cable rollers 17, 18 can be taken up onto the two cable rollers 17, 18. In this connection, preferably the first cable roller 17 is coupled to the first kinematic coupling 7 and the second cable roller 18 is coupled by drive engineering to the second kinematic coupling 8.
In the preferred embodiment shown in
In certain applications, it can be advantageous for the drive cable 6 to be made as a closed loop which loops the two cable rollers 17, 18. This is shown in
In the preferred embodiments shown in
In conjunction with the configuration of the cable-operated speed transforming transmission 5, it was pointed out above that, in the embodiment shown in
Depending on the hatch arrangement, however, it can also be such that the driving force necessary for positioning the hatch 1 in the closed position is especially high. Then, it is preferably provided that, in the motorized movement of the hatch 1 into the closed position, the driving force is transmitted over the positioning region via the two drive trains 3, 4 and that in the motorized movement of the hatch 1 into the open position, the driving force is transmitted over the positioning region solely via the first drive train 3.
Depending on the configuration of the cable-operated speed transforming transmission 5, adaptation of the effective drive cable length is necessary. For this purpose, it is preferably provided that the effective drive cable length can be set by a correspondingly adjustable attachment of the drive cable 6. There can be a clamp or screw attachment for this purpose.
In the above addressed cable-operated speed transforming transmission, stretching of the drive cable 6 cannot fundamentally be precluded. Therefore, in a preferred configuration, there is a cable tensioning device 19 which applies a force to the drive cable 6 perpendicular its the lengthwise extension at an engagement point. The cable tensioning device 19 preferably has a movable tension roller 20 which is spring-loaded in the direction of the drive cable 6. A change of the cable tension, for example by stretching of the drive cable 6, is thus associated with the corresponding deflection of the tension roller 20. This cable tensioning device 19 is shown by way of example in
A similar effect can be achieved by the drive cable 6 having an elastic element. The elastic element can be, for example, an interposed spring or the like. 100461 Another teaching which acquires independent importance relates to a drive arrangement which is largely “resistant” to tolerances in the two drive trains 3, 4. This drive arrangement is, in terms of fundamental structure, one of the above described drive arrangements, the existence of the cable-operated speed transforming transmission 5 being immaterial to this further teaching. In this respect reference, should be made in the full scope to the aforementioned statements. In particular, all the above described versions, possibly omitting the cable-operated speed transforming transmission 5, can also be applied to the further teaching. Two preferred embodiments are shown in
This drive arrangement also has a drive motor 2, which is not shown in
It is important to the further teaching that, downstream from the drive motor 2, a differential 21 with two outputs 22, 23 is connected and that the two drive trains 3, 4 proceed accordingly from the two outputs 22, 23 of the differential 21.
The aforementioned “interposition” of the differential 21 ensures a uniform distribution of the driving force to the two drive trains 3, 4, even when tolerances occur in one of the drive trains 3, 4. Possible tolerances arise, for example, by the aforementioned stretching of a drive cable 6 which may be present.
The differential 21 is made preferably as an epicyclic gear. For this purpose, a series of durable standard designs is known. One example of this is a bevel gear transmission or planetary gear. The use of a planetary gear for the drive arrangement according to the further teaching is schematically shown in
At this point, the arrangement is such that the first drive element 25 is coupled to the output 22 of the planetary gear 21, specifically to the planet carrier 27. The second drive element 26 is coupled via a cable-operated speed transforming transmission 5 to the other output 3 of the planetary gear 21, specifically to the ring gear 28. Normally, the driving of the sun wheel 24 by the drive motor 2 causes movement of the functional element 1 in
The aforementioned arrangement is especially advantageous in that even considerable tolerances in the two drive trains 3, 4 do not adversely affect the function of the drive arrangement, for example by a resulting twisting of the functional element 1. If for example the drive cable 6 shown in
Numerous versions for implementation of the two drive trains 3, 4, especially of the corresponding kinematic couplings 7, 8 are conceivable. One example is, in turn, outfitting the kinematic couplings 7, 8 with a geared spindle drive. Other possibilities comprise assigning cable, chain or V-belt drives to the kinematic couplings 7, 8. In this respect, reference should be made to the prior art.
The aforementioned drive arrangement with a differential 21 is especially advantageous since, fundamentally, cable length equalization, such as, for example, the aforementioned cable tensioning device 19, can be eliminated. This leads to a considerable reduction of costs.
Especially advantageous is the fact that, with the aforementioned drive arrangement with a differential 21, also especially large-area functional elements 1 can be driven without the danger of twisting. In motorized positioning of these large-area functional elements 1, correspondingly great distances must be bridged by drive engineering; this generally leads to considerable tolerances to be expected. They are automatically equalized, as described above, by the drive arrangement in accordance with the invention.
There can also be an intermediate gearing 29 in the aforementioned sense, alternatively or additionally, in the first drive train 3 and/or in the second drive train 4. In the embodiment shown in
In order to ensure manual actuation, if necessary, in a further preferred configuration, a clutch 30 is connected between the drive motor 2 and the drive trains 3, 4. In the embodiment shown in
The clutch 30 can be moved into the engaged state in which the drive motor 2 is coupled by drive engineering to the drive trains 3, 4. The clutch 30 can also be moved into the disengaged state in which the drive motor 2 is separated from the drive trains 3, 4. Then, the functional element 1 can be positioned independently of the drive motor 2. If the drive motor 2 is made self-locking, it blocks the functional element 1 in the disconnected state with the clutch 30 in the engaged state. Self-locking can be implemented by the drive motor 2, as such, being made self-locking, or by other, optional, downstream gearing being made self-locking.
It is especially advantageous if the clutch 30 can be moved, in addition, into an intermediate engaged state with reduced transmission torque or with reduced transmission force. This intermediate engaged state is designed such that the functional element 1, when the clutch 30 is in the intermediate engaged state, is kept in its current position by the intended self-locking at any time, but can be positioned by manual actuation with a predetermined minimum actuating force. However, in an emergency, for example, when the voltage supply fails during motorized actuation of the functional element 1, this can be advantageous. In such an emergency, the clutch 30 would preferably drop directly into the intermediate state in which the functional element 1 is held as described above in the current position. Uncontrolled slamming of the functional element 1 which is made optionally as a hatch is thus precluded even when the voltage supply fails.
For the aforementioned function in emergency operation, the clutch 30 is designed such that, when the voltage supply fails, it drops automatically into the intermediate state and not into the disengaged state, for example, by the action of the force of a spring or a permanent magnet. The configuration of this clutch is the subject matter of European Patent Application EP 1 602 796 A2 and corresponding U.S. Patent Application Publication 2005/277512 to which the applicant refers and the contents of which are hereby made fully the subject matter of this application.
In an especially preferred configuration, the clutch 30 has a planetary gear with a planet carrier which can be braked for engagement via a brake 31. This is also explained in the above referenced application. Reference should be made expressly thereto. Of course, here there can also be braking of the sun wheel or of the ring gear.
It was explained farther above that the drive cable 6 can be made as a closed loop which loops the two cable rollers 17, 18. In this connection, it is pointed out that the drive cable 6 can also have two cable pieces which can be taken up preferably onto the two cable rolls 17, 18. With the corresponding design, the cable pieces can have the same action as the above described loop.
Fundamentally, it can be provided that the cable-operated speed transforming transmission 5 comprises simply one drive cable 6 which runs via cable rollers or the like. An especially flexible arrangement arises by the cable-operated speed transforming transmission 5 being made, at least in part, as a Bowden cable 32 with a Bowden cable jacket 33 and Bowden cable core 34 as shown in
Fundamentally, it can be provided that solely traction force can be transmitted via the Bowden cable 32. This leads to a simple configuration of the Bowden cable core 34. A version is also conceivable in which that the Bowden cable 32 is made as a “push-pull” Bowden cable and that both traction force and also compression force can be transmitted via the Bowden cable 32. In this way, the above described loop-like configuration of the drive cable 6 can be omitted.
The arrangement shown in
In the embodiment shown in
The description above shows that numerous combination possibilities of kinematic couplings, intermediate gearing, differentials and clutches are conceivable. In order, on the one hand, to maximize design freedom, and on the other hand, to simplify production, it is provided in an especially preferred configuration that the drive arrangement can be assembled from individual modules. One module could be the kinematic coupling which would be made identical for both drive trains 3, 4. Another module would be the intermediate gearing 29, 29a or the clutch. Optionally, it is also conceivable for the intermediate gearing 29, 29a, on the one hand, and the differential 21, on the other hand, to have identical housings.
It is pointed out that all of the above described drive arrangements, including the various versions, can be applied to all conceivable functional elements 1 of a motor vehicle. Accordingly, the aforementioned functional element 1 can be a tailgate, the hood or cargo space hatch which can be positioned by a motor and the trunk lid of a motor vehicle which can be positioned by a motor. Other examples for the functional element 1 are all types of side doors which can be positioned by a motor, especially sliding doors which can be positioned by a motor. Other functional elements 1 are convertible roofs, large-area roof windows or the like which can be positioned by a motor.
Finally, it must be considered that the representations according to FIGS. 1 to 6 are not to scale. Dimensions and ratios of lengths cannot be taken from these descriptions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20 2005 000 462.6 | Jan 2005 | DE | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP06/00221 | Jan 2006 | US |
| Child | 11776861 | Jul 2007 | US |
