Electric drive for a motor vehicle

Abstract

The invention relates to an electric drive for a motor vehicle, comprising an electric motor (1), a drive wheel (3), in particular a worm wheel (3), with a cam profile (5) which interacts with the electric motor (1), and a lever (8) which can be loaded by the cam profile (5). The cam profile (5) is designed to be rotated through a full rotation (360°) in order to load the lever (8). According to the invention, the cam profile (5) is designed to be rotated through more than a full rotation (> 360°).

Description

Technical Field

[0001] The present invention relates to an electric drive device for use in motor vehicles, the electric drive device comprising: an electric motor; a drive wheel, particularly a worm gear, having a cam-shaped portion / convex profile portion interacting with the electric motor; and a rod that can be loaded by the cam-shaped portion, wherein the cam-shaped portion rotates a full revolution (360°) to load the rod. Background Technology

[0002] Electric drive systems used in motor vehicles are characterized by their robust structure and the ability to operate at low voltages, typically 12V or 24V DC. Consequently, specialized measures are usually required to transmit the rotational motion of the motor in order to achieve force-intensive operation. This transmission is typically provided by the motor engaging the external teeth of a worm gear located on its output shaft. Furthermore, the cam-forming section typically has a helical profile to enable the loading of a rod abutting against and loaded by means of the helical profile of the cam-forming section with increased torque.

[0003] This principle has been verified, and therefore such an electric drive device can be used, for example, to control locking devices, as described in document DE 197 02 420C5 of this type. In practice, by means of an adjusting element or adjusting drive device implemented in this way, functional positions corresponding to worm gear rotation movements of 0° or 360°, 90°, 180°, and ultimately 270° can be achieved: “open,” “lock,” “anti-theft,” and ultimately “child-safe.” This is advantageous in principle.

[0004] Furthermore, similar electric drive units have recently been used in conjunction with locking actuators in charging equipment associated with electric or hybrid vehicles. Other applications of such electric drive units include raising and lowering window glass, adjusting mirrors, or adjusting seats. They can also be used to unlock / lock covers. Additionally, such electric drive units are used in vehicle locks or as locking / unlocking mechanisms. These drive units are characterized by a high-speed motor, whose high speed translates into relatively slow motion, while simultaneously increasing force or torque, resulting in a large transmission ratio.

[0005] While an intermediate transmission mechanism could be used in this situation, it increases technical complexity and friction, and is therefore generally avoided and not considered advantageous. However, the desire to improve the transmission ratios available to date remains constant. Currently, no simple and cost-effective solution is available for this purpose. This invention aims to remedy this in its entirety. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to further develop such an electric motor drive device for motor vehicles, so as to provide an increased transmission ratio while being simple in structure and low in cost.

[0007] To address this technical problem, the present invention proposes a cam-forming portion in an electric drive device of this type applied to motor vehicles, wherein the cam-forming portion is configured to achieve a rotation of more than one full revolution (>360°).

[0008] To enable detailed realization and implementation of more than one full rotation (>360°) of the drive wheel, particularly the worm gear, and consequently the cam-forming part, in this configuration, the rod is equipped with at least one first rod stop, and the drive wheel, particularly the worm gear, is equipped with a wheel stop, wherein the two stops interact in a position-dependent manner. That is, the rod stop is positioned on the rod loaded by the cam-forming part, while the wheel stop is located on the drive wheel, particularly the worm gear. The two stops interact in a position-dependent manner through the movement of the drive wheel, particularly the worm gear, and consequently through the movement of the cam-forming part, and the resulting rod oscillation motion. Typically, the first rod stop and the wheel stop interact as endpoint stops after the drive wheel, particularly the worm gear, has completed more than one full rotation.

[0009] Advantageously and therefore particularly preferably, the drive wheel is constructed as a worm gear. However, it is also conceivable that the drive wheel be constructed as a gear or a similar structure.

[0010] In summary, the present invention is based on the understanding that the rod and the first rod stop oscillate as the rod moves along with the drive wheel, particularly the worm gear, under the loading of the cam-shaped portion. Once the drive wheel, particularly the worm gear, has completed more than one full rotation, the first rod stop engages with the wheel stop and achieves the interaction described above. Accordingly, the first rod stop and the wheel stop together act as an end-stop device after the drive wheel, particularly the worm gear, has completed more than one full rotation, thereby braking the drive wheel, particularly the worm gear, and preventing it from "idling."

[0011] In the prior art according to DE 199 48 052A1 or also according to DE 103 61 168A1, although stops have been described in these documents, the combination of a first rod stop and a wheel stop, which interact in a position-dependent manner, has not been described.

[0012] This invention begins with the understanding that a rotation of more than one full revolution in the cam forming part can be used or realized, allowing a transmission ratio that is further improved compared to the prior art to be transmitted to the lever by means of the cam forming part. Thus, the lever can perform the desired adjusting movement with a torque that is improved compared to the prior art. This could be the indication of the functional state inside a vehicle lock, the closing or opening movement of a vehicle door, the raising or lowering of a vehicle window, etc., to name just a few application examples and possible adjusting elements that can be loaded by the lever.

[0013] To ensure that the electric drive unit can still be braked and stopped after the completion of its adjustment movement and thus avoids the previously described "idling motion," a first lever stop, together with a wheel stop, serves as an end-point stop and jointly defines the end-point stop, occurring at the end of a rotation of more than one full revolution of the drive wheel. Because the swinging motion of the lever and, consequently, the first lever stop, is utilized in this process, no potential collision between the first lever stop and the wheel stop occurs beforehand and during the swinging motion of the lever and the rotational motion of the drive wheel. Instead, the first lever stop swings into the typical circular path of the wheel stop on the outer periphery of the drive wheel only when the lever reaches its final swing position. This is the case after a rotation of more than one full revolution of the drive wheel. For this purpose, the first lever stop is typically arranged at the end of the lever furthest from the axis.

[0014] The lever is typically a double-arm lever with a first arm and a second arm. The first arm is usually equipped with a first lever stop at its end. Conversely, the second arm acts on the adjusting element. This can be done indirectly or directly. The two arms can have the same or different lengths from the central axis or rotation axis.

[0015] Besides the possibility that the first lever stop and the wheel stop interact as an end-stop device, more precisely, after the complete adjustment movement of the lever has ended, that is, after the drive wheel has rotated more than one full revolution, the first lever stop can also interact with the cam-forming part as another end-stop device. In this case, this additional end-stop device is regularly defined and implemented at the start of the moving motion. For this purpose, the cam-forming part typically has a recess for the lever, preferably near the axis.

[0016] Therefore, the rod can extend into the recess, more precisely, at the start of the adjusting movement of the drive wheel and, consequently, the cam-forming part. Advantageously, the recess interacts with the first rod stop as an additional end-stop device at the start of the rotational movement of the drive wheel. Starting with the rod or its first arm positioned within the recess by the first rod stop, the rotational movement of the drive wheel now causes the rod to oscillate increasingly with the aid of the cam-forming part, more precisely, radially outward about the axis of the drive wheel. This oscillating movement continues through the cam-forming part until the loading on the rod ends, and only ends when the drive wheel has completed more than one full rotation, and then the first rod stop interacts with the wheel stop at the drive wheel as an end-stop device.

[0017] However, within another variant with independent significance, the rod can also be equipped with an additional second rod stop. Furthermore, it is designed such that the additional second rod stop interacts with the wheel stop in a position-dependent manner, which also applies to the first rod stop and the wheel stop.

[0018] Here, it is typically done as follows: the first lever stop and the wheel stop interact as endpoint stops as described above after the drive wheel has completed more than one full rotation; additionally, the second lever stop and the wheel stop interact as additional endpoint stops in this variant when the rotation of the drive wheel begins. That is, at the start of the rotation of the drive wheel, the second lever stop and the wheel stop also define endpoint stops. In both variants, at the end of the rotation of the drive wheel, the first lever stop and the wheel stop together interact as additional endpoint stops. Thus, the rotation of the drive wheel between the two endpoint stops is mechanically determined without concern for possible idling during lever loading or during the reverse movement of the electric drive. In this way, movement can be made particularly precisely by means of the lever-loaded adjustment element.

[0019] The result is an electric drive unit for motor vehicles, which, due to the design of its cam-shaped portion, can achieve rotations exceeding one full revolution and, in particular, can transmit a high gear ratio from the motor via the drive wheel and the cam-shaped portion to the lever to load the desired adjustment element. For example, the lever can be connected indirectly or directly to the rotary lock fork of a motor vehicle door lock so as to load the rotary lock fork in the sense of a closing movement and thus close the corresponding motor vehicle door. Other applications, as described at the beginning, are also contemplated.

[0020] Therefore, an additional subject of the present invention is a vehicle lock, particularly a vehicle door lock, equipped with such an electric drive device. Here, the drive device can be used to electrically open the relevant vehicle lock. This is achieved indirectly by manipulating a release lever or directly by directly loading the locking pawl. Furthermore, the relevant drive device can be used to individually or in combination to access and implement lock functions such as child safety, anti-theft security, central locking, etc.

[0021] Drive wheels are typically constructed as injection-molded parts, allowing for particularly simple and inexpensive manufacturing of drive wheels including cam-shaped portions. Embodiments made of metal or plastic have proven effective. Therefore, a particularly simple structure is provided for at least one additional rod stop or two rod stops. In fact, the rod itself can also be made of plastic or metal. This results in very low manufacturing costs. This is a major advantage of the invention. Attached Figure Description

[0022] The present invention will now be described in detail with reference to the accompanying drawings, which illustrate only one embodiment; wherein:

[0023] Figure 1A and Figure 1B A first variant of the invention is shown in the indicated rotational motion of the drive wheel, and

[0024] Figure 2A and Figure 2B A second implementation scheme with a variation is shown. Detailed Implementation

[0025] The accompanying drawings show an electric drive system applied to a motor vehicle. For this purpose, the corresponding drive system has a motor 1 that operates sequentially and typically with a low DC voltage, such as 12V, 24V, or 48V. The motor 1 has an output worm 2 arranged on its output shaft, which meshes with the outer teeth of a worm gear 3. Thus, the worm gear 3 can, in particular, move around its shaft 4... Figure 1B and Figure 2B The movement shown is counterclockwise. This is based on... Figure 1A and Figure 2A During the counterclockwise motion starting from the corresponding initial or rest position, the worm gear 3, according to this embodiment, completes more than one full rotation (>360°). This is particularly possible by means of... Figure 1B Understandably, according to the attached drawings, the worm gear 3 and the cam forming part 5 arranged on or at the worm gear are in the... Figures 1A to 1B Or from Figures 2A to 2BThe worm gear 3 completes a full rotation during the transition, and then, in this example, rotates further by approximately 35°. That is, the worm gear 3 and the cam forming part 5, along with the worm gear, complete a total angle of almost 400°, or 360° + approximately 35°, in both embodiments. Of course, this is merely exemplary and not limiting.

[0026] The electric drive and the corresponding adjustment movement of the worm gear 3 in the sense of counterclockwise movement around its axis 4 correspond to the situation where the cam-shaped portion 5 on the worm gear 3 loads a rod 8 made of plastic or metal. For this purpose, the cam-shaped portion 5 is equipped with a helical line 7 that originates from a recess 6 near the axis of the cam-shaped portion 5. That is, the worm gear 3 is equipped with a helical cam-shaped portion 5, which has a recess 6 near the axis on one side and a helical line 7 on the other side. Here, the helical line 7 originates from the recess 6 and is characterized by having a radius that increases relative to the axis 4 in the operating direction or in the counterclockwise direction, thereby allowing the rod 8, loaded by the cam-shaped portion 5 and sliding along the helical line 7, to bear an increased torque load.

[0027] In fact, lever 8 is a double-arm lever, which is supported in the housing in a manner that allows it to rotate about an axis 9 located centrally according to this embodiment. The housing can be the housing of a vehicle lock or locking actuator, a window regulator actuator, a hatch actuator, etc. Lever 8 itself acts on the adjusting element 10, or more precisely, indirectly or directly on the adjusting element. In fact, the clockwise movement of lever 8 about its axis 9 is transmitted to the adjusting element 10, as in the case of a... Figure 1A Towards Figure 1B and from Figure 2A Towards Figure 2B This can be seen from the transition.

[0028] With the drive mechanism closed, the adjusting element 10 can be a rotating lock fork of a vehicle door lock (not explicitly shown) mentioned earlier. However, in principle, the adjusting element 10 can also be a window that can be raised and lowered, a vehicle door, a vehicle hood, etc. For this purpose, the lever 8 completes the... Figure 1B or Figure 2B The adjustment movement shown in the figure is clockwise around its axis 9, or more precisely, the adjustment movement is accomplished with increased torque.

[0029] As already described, according to the present invention, the cam forming part 5 is configured to achieve a rotation of more than one full revolution (>360°), and according to this embodiment, the cam forming part 5 can perform a rotational movement of approximately 400°. The lever 8 is equipped as a double-arm lever with a first arm 8a and a further second arm 8b. The further second arm 8b interacts with the adjusting element 10. Conversely, the first arm 8a rests against the cam forming part 5 or its helical line 7 and oscillates clockwise around the lever's axis 9 via the counter-clockwise movement of the worm gear 3.

[0030] Therefore, the double-arm rod 8, with its first arm 8a, according to Figure 1A and Figure 2A It extends into the recess 6 of cam 5 from its initial position. From according to Figure 1A and Figure 2A Starting from the initial position, and from the corresponding adjustment angle of 0° for the cam forming part 5 and, consequently, the worm gear 3, the counterclockwise rotational movement of the worm gear 3 and, consequently, the cam forming part 5 about the axis 4 now causes the helical line 7 of the cam forming part 5 to move against the arm 8a of the rod 8. In the example shown, the cam forming part 5 and therefore the helical line 7 extend in a plane parallel to the worm gear 3. As the distance between the helical line 7 and the axis 4 of the worm gear 3 increases, the arm 8a of the rod 8 swings more and more about the axis 9, more precisely clockwise, and thereby subjecting the adjusting element 10 to the desired load.

[0031] Since the cam forming part 5 completes a rotation of more than 360° (more than one full rotation) during this process, the overall transmission ratio provided by the motor 1 can be increased, and the rod 8 is ultimately loaded using this transmission ratio. To ensure precise braking and stopping of the motor 1 at the end of this movement, the rod 8 is equipped with at least one first rod stop 11, and the worm gear 3 is equipped with a wheel stop 12, wherein the two stops 11 and 12 interact in a position-dependent manner. Position-independent interaction means that the two stops 11 and 12 interact or not interact depending on the position of the worm gear 3 and the position of the rod 8. In this embodiment, the interaction between the first rod stop 11 and the wheel stop 12 only occurs in the example case where the worm gear 3 has completed a rotation of approximately 400° (more than one full rotation). That is, the first rod stop 11 interacts with the wheel stop 12 as an endpoint stop device 11, 12 after the worm gear 3 has completed a rotation of more than one full rotation. This situation occurs in… Figure 1B and 2B As shown in the image.

[0032] In fact, it can be seen that the wheel stop 12 is first formed on the outer periphery of the worm gear 3, that is, like the cam forming part 5 on the upper or front side of the worm gear 3 shown in the attached drawings. Thus, the wheel stop 12, according to... Figure 1A and Figure 2A Starting from the initial position, a counter-clockwise movement is performed around axis 4, and in the example case, the movement ends at approximately 400° according to... Figure 1B or Figure 2B The position of the first stop 11 is based on... Figure 1A and Figure 2A In its initial position inside the recess 6 directly adjacent to the shaft 4 of the worm gear 3. The counterclockwise rotation of the worm gear 3 causes the helical line 7 to abut against the arm 8a of the rod 8 or against the first rod stop 11, thereby causing the arm 8a to gradually swing radially outward relative to the shaft 4 when it abuts against the helical line 7. Thus, the rod 8 completes its movement in... Figure 1B or Figure 2B The clockwise movement is shown in the figure, and the other second arm 8b of the lever 8 is used to load the adjusting element 10.

[0033] Only at the end of the spiral line 7 does the first rod stop 11 reach the area of ​​influence of the wheel stop 12, or swing into its track on the outer periphery of the worm gear 3, thereby braking the further rotation of the worm gear 3 in a counterclockwise direction. This is because the wheel stop 12 moves or is moved towards the first rod stop 11, which has swung into its track. Therefore, the first rod stop 11 and the wheel stop 12 together serve as the endpoint stop devices 11 and 12 after the worm gear 3 has completed more than one full rotation.

[0034] For this purpose, the first stop 11 is arranged on the end of the rod 8 away from the axis, according to this embodiment, on the end of a rod arm or the first rod arm 8a away from the axis. Furthermore, according to... Figure 1A and Figure 1B Within the scope of the first embodiment, the design is such that the first rod stop 11 and the cam forming portion 5 interact as additional end-point stop devices. For this purpose, the cam forming portion 5 has a recess 6 near the axis for the rod 8, and the associated recess 6 interacts with the first rod stop 11 as additional end-point stop devices 6, 11 at the start of the rotational movement of the worm gear 3. This is in Figure 1A As shown in the diagram, it can be seen that when the rotational movement of the worm gear 3 begins, the rod 8 or its first lever arm 8a enters the recess 6 of the cam forming part 5. The first rod stop 11, arranged on the end of the rod 8 or the first lever arm 8a away from the axis, is now... Figure 1A The rod moves against the recess 6 in its initial position, which, together with the first rod stop 11, defines another end stop device 6, 11.

[0035] exist Figure 2A and Figure 2BThe text describes a variant in which, although the first stop 11 is still implemented, it also interacts with the wheel stop 12 as an endpoint stop device 11, 12 after the worm gear 3 has completed more than one full rotation, as described in... Figure 2B As indicated in the text. However, the situation is different at the beginning of the rotational motion of the worm gear 3, because in this case... Figure 2A The first stop member 11 does not move against the recess 6 or the edge of the recess 6, but is spaced apart from the recess. However, in order to achieve a mechanically defined and fixed position, according to Figure 2A and Figure 2B In one embodiment, the rod 8 is equipped with an additional second rod stop 13. Like the first rod stop 11, the second rod stop 13 also interacts with the wheel stop 12 in a positional manner. In fact, in Figure 2A At the beginning of the rotation of the worm gear 3, the interaction between the second rod stop 13 and the wheel stop 12 can be observed, while the first rod stop 11—as is customary—interacts with the wheel stop 12 as an endpoint stop device 11, 12 at the end of the rotation of the worm gear 3.

[0036] In fact, the second rod stop 13 and the wheel stop 12 define additional end-point stops 13 and 12 at the start of the rotational motion of the worm gear 3. This is in Figure 2A It is shown in the diagram and can be clearly understood.

[0037] Therefore, the wheel stop 12 is a tab-shaped stop 12, which is not only arranged on the outer peripheral side of the worm gear 3 on the front or upper side of the worm gear 3, but also extends radially relative to the shaft 4 of the worm gear 3. In this way, the tab-shaped wheel stop 12 has two stop surfaces 12a and 12b, which are opposite to each other with respect to the tab. The stop surface 12a is realized and arranged on the front side of the tab-shaped stop 12 in the direction of movement (counterclockwise direction), while the other second stop surface 12b is arranged on the rear side. A similar situation also applies to the first embodiment. Thus, according to Figure 2A When the rotational movement begins within the range of the view, the stop 12 abuts against the second rod stop 13 of the rod 8 with the stop surface 12b.

[0038] If based on Figure 2A Starting from the initial position, the worm gear 3 moves counterclockwise around its axis 4, and the stop 12 moves away from the second stop 13 until the stop 12 has occupied the position according to the... Figure 2B The position. In this functional position, the lever 8 swings radially outward by means of the cam forming part 5 to the position according to Figure 2BIn the position, the first stop 11 extends into the track of the stop 12, and the stop 12 moves against the first stop 11 with its front stop surface 12a. In both cases, the electric drive is mechanically stopped and braked, respectively.

[0039] Another possibility, not shown, is that the cam-forming part 5 does not have a helical line 7 oriented in the plane, but instead is equipped with a spirally extending helical part. In this case, the arm 8a of the lever 8 that interacts with the cam-forming part 5 can be equipped, for example, with a roller that spatially follows the spirally extending part of the cam-forming part 5. Therefore, the double-arm lever 8 does not perform a swinging motion about its axis 9, but instead moves upward about an axis located in the plane of the figure, thus causing the other arm 8b to perform a downward motion, which can then be transmitted to the adjusting element 10.

[0040] List of reference numerals in the attached diagram:

[0041] 1. Motor

[0042] 2 Output worm gear

[0043] 3 Drive wheel / worm gear

[0044] 4-axis

[0045] 5 Cam forming section

[0046] 6. Recess near the shaft

[0047] 7. Spiral line

[0048] 8 strokes

[0049] 9. The axis located in the middle

[0050] 10 Adjustment elements

[0051] 11 First rod stop

[0052] 12 wheel stops

[0053] 11, 12 End Stop Devices

[0054] 12a, 12b stop surfaces

[0055] 13 Second rod stop

[0056] 13, 12 Other end-point stop devices

Claims

1. An electric drive device for use in a motor vehicle, the electric drive device comprising: a motor (1); a drive wheel (3) having a cam-shaped portion (5) interacting with the motor (1); and a rod (8) loadable by the cam-shaped portion (5), wherein, The cam forming part (5) rotates a full revolution in order to load the rod (8). Its features are, The cam forming part (5) is configured to achieve a rotation of more than one full rotation. The lever (8) is equipped with at least one first lever stop (11), and the drive wheel (3) is equipped with a wheel stop (12), wherein the first lever stop (11) and the wheel stop (12) interact in a position-dependent manner. The rod (8) is equipped with an additional second rod stop (13). The first rod stop (11) and the wheel stop (12) interact as end-stop devices after the drive wheel (3) has completed more than one full rotation. The second rod stop (13) and the wheel stop (12) interact as another end-stop device when the drive wheel (3) begins to rotate.

2. The driving device according to claim 1, characterized in that, The drive wheel (3) is a worm gear.

3. The driving device according to claim 1 or 2, characterized in that, The first rod stop (11) is arranged on the end of the rod (8) away from the axis.

4. The driving device according to claim 1 or 2, characterized in that, The first stop (11) and the cam forming part (5) interact as another end-point stop device.

5. The driving device according to claim 4, characterized in that, The cam forming part (5) has a recess (6) for the rod (8).

6. The driving device according to claim 5, characterized in that, The recess (6) and the first rod stop (11) interact as an additional end-stop device when the rotational motion of the drive wheel (3) begins.

7. A motor vehicle lock, characterized in that, It is equipped with an electric drive device according to any one of claims 1 to 6.

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