DE102020132027A1 - Electromotive drive unit for motor vehicle applications - Google Patents

Abstract

The subject matter of the invention is an electromotive drive unit for motor vehicle applications, in particular a locking unit for an electric charging device of a motor vehicle. The drive unit has an electric motor (2) and possibly a downstream gearbox (3, 4). Furthermore, a movable adjusting element (7) and also a control element (5) and at least one spring (7) for acting on a sensor (6) are realized. According to the invention, the spring (7) is designed as a leaf spring (7) which is arranged between a control contour (10a) of the control element (5) and the sensor (6) and which has a ramp (7a) on the control contour (10a) to act on the sensor ( 6) slides along.

Description

The invention relates to an electromotive drive unit for motor vehicle applications, in particular a locking unit for an electric charging device of a motor vehicle, preferably an electric or hybrid motor vehicle, with an electric motor and possibly a downstream transmission, also with a movable actuating element, and with a control element and at least one spring for loading a sensor.

Accumulators of electric or hybrid motor vehicles have to be supplied with electrical energy on a regular basis. This is usually done using a charging infrastructure, which typically includes charging stations. For the charging process with electrical energy, the charging plug of the charging station is generally coupled to a charging socket on the motor vehicle and locked in a releasable manner. The interlock is necessary to avoid health hazards, for example, since high voltage is generally used at this point. The locking also ensures that only previously identified users lawfully draw the energy provided by the charging station and misuse is prevented. For this purpose, the operator is usually identified before such a loading process and an authorization check is carried out using an identification signal, as is generally the case in the WO 2010/149426 A1 is described.

Details of an electromotive drive unit designed in this context as a locking unit i. V. m. the associated electrical charging device are exemplified in DE 10 2018 114 205 A1 described by the applicant. Typically, the drive unit or locking unit is modularly coupled to a loading module. For its part, the charging module has a charging socket that is detachably coupled to the charging plug of the charging infrastructure. This is ensured by the actuating element or locking element, which can generally be moved linearly with the aid of the locking unit.

In principle, of course, other areas of application of such an electromotive drive unit are also conceivable. For example, the linearly displaceable actuating element can also be used as an opening element for a motor vehicle door. It is also conceivable to use such an electromotive drive unit to lock a tank flap or other flaps. As a rule, however, such electromotive drive units are used as a locking unit or locking actuator i. V. m. electrical charging devices used, as in the previously described and referenced DE 10 2018 114 205 A1 be described in detail.

A generic electromotive drive unit is through the CN 202695855 U known. At this point, a control disc is provided, which is obviously biased by a local spring. A sensor or switch is acted upon with the aid of the control disc in order to be able to query the associated position of the actuating element.

through the DE 10 2009 039 652 A1 other spring arrangements have become known that i. V. m. serve a control cam to act on a switch. The shows something similar DE 10 2013 008 550 A1 . In fact, a ramp that acts on a microswitch is already being used at this point.

The state of the art has basically proven itself. However, when the sensor is acted upon by means of the control element, in practice there are often problems such that the sensor signal generated lacks the necessary accuracy and resolution. In fact, both prerequisites are of particular importance in order to be able to draw precise conclusions about the movement of the actuating element via the sensor acted upon by the control element. The invention is based on the finding that the position of the actuating element or locking element must be used to determine without a doubt whether the charging plug is correctly locked in the charging socket. Only then will the charging process start and can any health hazards caused by the high voltage observed at this point be reliably ruled out.

So far, the overall procedure has been that within the framework of the generic teaching after CN 202695855 U the sensor or switch is acted upon in the axial direction. However, the actuation of the sensor or switch can result in tilting movements of the switch itself or of an associated switching cam. Such tilting movements in particular have a negative effect on the accuracy of the sensor signal. In addition, the forces exerted on the switch or sensor by the action of the control contour are or can be so great that this results in permanent damage to the switch.

For this reason, the invention is based on the technical problem of developing such a drive unit so that a damage-free operation of high resolution is guaranteed.

To solve this technical problem, the invention proposes in a generic electromotive drive unit for motor vehicle applications that the spring for loading the sensor is designed as a leaf spring arranged between a control contour of the control element and the sensor, which has a ramp on said control contour Impingement of the sensor slides along.

According to the invention, the spring experiences a special positioning in order to act on the sensor, namely between the control contour of the control element on the one hand and the sensor on the other hand. As a result, movements of the control contour, which are to be scanned using the sensor, are not transmitted directly to the sensor, but rather using the interposed leaf spring. In this way, there is first of all a mechanical decoupling between the control contour of the control element on the one hand and the sensor on the other, so that any load peaks, tilting movements, etc. due to the principle of the sensor or a switch or microswitch usually used at this point are eliminated by the interposed leaf spring be kept away.

In addition, a leaf spring is advantageously used as the spring, ie a spring formed from a metal strip, the metal strip having a narrow side and a wide side. In principle, the leaf spring in question can of course also be made from a different spring material, for example plastic. Mixed forms in the sense of metal/plastic are also conceivable.

According to the invention, the leaf spring is now equipped with the ramp, which slides along the control contour of the control element to act on the sensor. In this context, the ramp also ensures that any mechanical load peaks in relation to the sensor to be acted upon are dampened. As already explained, the sensor is typically a switch and in particular a microswitch, which according to the invention generally rests with its switching cam on the leaf spring in question. That is, the leaf spring works on the switch cam, which in turn actuates the switch or is part of the switch. Due to the design achieved according to the invention and the interposition of the leaf spring, any load peaks on the switching cam and/or tilting movements are now reliably avoided.

The procedure here is regularly such that the narrow side of the leaf spring is aligned along the axial direction in which, according to the invention, sensor signals are measured with the aid of the sensor or switch. For this purpose, the control contour has a different axial extension in said axial direction, which is scanned by the ramp of the leaf spring and transmitted to the switch cam of the switch in the example. The axial direction is determined by the longitudinal extent of the control element.

In addition, the broad side of the leaf spring is predominantly aligned at the same level as a plane spanned by a control disc as part of the control element. In fact, the control disk advantageously represents a part of the control element and is equipped with the control contour.

The control element is now set in rotation with the help of the electric motor and, if necessary, the downstream gear. These rotations correspond to the control element sliding along the ramp of the leaf spring with its control disk. Since the control disc has the control contour and the control contour itself has areas of different axial extent, the ramp of the leaf spring in contact with the control contour is deflected to a greater or lesser extent by the latter. The deflections of the ramp of the leaf spring are then in turn transmitted to the sensor, specifically serving to act on the switching cam and thus the switch in the example.

That is, the rotational movement of the electric motor or the downstream gear is converted into an axial movement of the leaf spring or its ramp sliding along the control contour with the aid of the control element. This axial movement is transmitted to the sensor and results in sensor signals that can typically be evaluated using a control unit connected to the sensor. Since the electric motor, with a possibly downstream gearbox, not only causes the control element to rotate, but also works on the movable actuating element, the movement of the actuating element can be deduced from the sensor signals as desired. In other words, the sensor ultimately serves to record the movement of the actuating element.

For this purpose, the actuating element usually has a U-shaped receptacle into which an eccentric of a gear part engages. Of course, such a gear is basically superfluous, although it is generally provided and implemented. The fact that the eccentric on the transmission part in the Engages U-shaped receptacle of the actuating element, rotary movements of the associated transmission part are converted into corresponding linear movements of the actuating element. If the electromotive drive unit is designed as a locking unit at this point, corresponding linear movements of the locking element or actuating element correspond to this.

According to a further advantageous embodiment, the control element is prestressed in the axial direction with the aid of the leaf spring. That is, the control is biased by the leaf spring in the direction of a stop in a housing. As a result, any axial movements of the control element can be easily compensated for with the help of the leaf spring interposed between the control element and the sensor. Such axial movements of the control element may occur when there is a change in direction of the electric motor and consequently of the downstream transmission.

In order to implement and realize this in detail, the control element is usually mounted on a drive pin in a rotationally fixed and axially displaceable manner. This drive pin can be part of a transmission part. In addition, this usually means that the design is such that the control element is not only mounted in a rotationally fixed manner on the drive pin in question, but also has an axial displaceability relative to the drive pin. As a result, the control element can compensate for any axial movements of the drive or the transmission part, for example due to the reversal of direction already mentioned.

In order to implement in detail the axially movable and at the same time non-rotatable coupling between the control element and the drive pin or the transmission part having the drive pin, the control element usually has an anti-rotation device which engages in a receptacle. In the example described, this recording can be found in or on the transmission part. The anti-rotation lock may be a pin that engages in the receptacle and is adapted to the size of the receptacle. In any case, this provides a coupling between the control element and the associated gear part that is both axially movable and non-rotatable.

The strip-shaped leaf spring is usually connected at one end to the previously mentioned housing. The housing is typically a plastic housing which accommodates and encloses the entire electromotive drive unit in its interior. The other end of the leaf spring, on the other hand, is equipped with an end stop. The end stop can interact with a stop on the housing to limit travel. This means that as soon as the control element or its control disk has completed a certain travel distance, the leaf spring moves with its end stop against the stop. This results in travel limitation and any overstretching of the switching cam is avoided, for example. In principle, this also prevents damage to the sensor according to the invention.

In addition, and advantageously, the leaf spring has a stiffened area for interaction with the sensor. The stiffened area is specifically implemented in such a way that it has an L or U shape in cross section. Of course, combinations are also conceivable. That is, the leaf spring is widened in the stiffened area in question or equipped with additional projections in order to be able to provide the mentioned L or U shape in cross section and thereby define the stiffened area. Otherwise, the leaf spring has its consistent stripe-like character throughout.

Finally, the leaf spring can also be equipped with an elastic area that changes shape in the axial direction. The elastic area is designed in such a way that it changes its shape in the manner of an accordion. This provides the desired shape elasticity, ie a macroscopic elasticity, if you will, in comparison to the microscopic elasticity inherent in the material for the leaf spring. The area of the leaf spring that changes shape like an accordion can be designed and implemented in detail in such a way that the leaf spring is deformed in a wavy manner in the axial direction.

As a result, an electromotive drive unit for motor vehicle applications is described and made available, which has proven itself in particular as a locking unit for an electric charging device of a motor vehicle. For this purpose, the electromotive drive unit has a linearly movable actuating element or locking element. The position of this actuating element or locking element is queried using a sensor. In order to increase the accuracy of the sensor signals generated and to avoid any damage to the sensor even over long time scales, a control element which is set into rotation using the electromotive drive unit is provided according to the invention, which works with the interposition of a leaf spring on the sensor. The interposed leaf spring protects the sensor from mechanical stress peaks and also from any tilting movements transmitted to the sensor genes that may be explained by movements of the drive as such or by changing friction conditions.

For this purpose, the leaf spring is specially shaped, has an end stop to limit travel and a stiffened area so that the sensor and a switching cam in particular can be actuated properly. An additionally provided elastic area ensures that it is not possible to apply pressure to the sensor beyond its internal end stop, so to speak, and that this is sort of absorbed by a deformation of the elastic area. This reliably prevents damage to the sensor, even over long time scales.

At the same time, the leaf spring ensures that the control element is coupled to the drive in a rotationally fixed manner, but that movements in the axial direction are deliberately permitted. As a result, the drive cannot transfer any axial movements, for example in the event of a direction reversal, to the sensor, which is therefore optimally protected against damage during operation, although it delivers a particularly precise and reliable sensor signal. This is where the main advantages can be seen.

• 1 die elektromotorische Antriebseinheit in einer perspektivischen Übersicht,
• 2 den Gegenstand nach der 1 in einer Detailansicht im Bereich des Steuerelementes inklusive Sensor und Blattfeder,
• 3 den Gegenstand nach der 2 in eine Ansicht von oben und
• 4A, 4B die Betätigung des Sensors durch die zwischengeschaltete Blattfeder im Detail.

The invention is explained in more detail below with reference to a drawing that merely represents an exemplary embodiment; show it:

• 1 the electromotive drive unit in a perspective overview,
• 2 the item after the 1 in a detailed view in the area of the control element including sensor and leaf spring,
• 3 the item after the 2 in a top view and
• 4A , 4B the actuation of the sensor by the intermediate leaf spring in detail.

The figures show an electromotive drive unit for motor vehicle applications. With the help of the electromotive drive unit, a 1 illustrated actuating element 1 moves in the linear direction illustrated there by a double arrow. In the exemplary embodiment and not restrictively, the electromotive drive unit is a locking unit or a locking actuator for an electric charging device of a motor vehicle. For this purpose, the locking unit or the locking actuator is coupled to a charging module of the electrical charging device. For this purpose, the charging module has the charging socket on the vehicle side, into which a charging plug on the charging column engages and is releasably locked with the aid of the actuating element 1 or locking element 1 . The topological arrangement corresponding to this is exemplified in the one previously described DE 10 2018 114 205 A1 presented by the applicant, to which reference is expressly made.

In its basic structure, the electromotive drive unit according to the invention has an electric motor 2 and a downstream gear 3, 4. The downstream gear 3, 4 has a gear part 4, with the help of which a control element 5 is set in rotation, which is used to act on a Sensor 6 is used. In addition, the transmission works 3, 4 on the movable actuator 1. In particular, based on the 2 and 3 one recognizes that a spring 7 is interposed between the control element 5 and the sensor 6, which will be considered in more detail below.

The transmission part 4 is equipped with an eccentric 8, which engages in a U-shaped recess 9 of the actuating element 1, as can be seen from the enlarged detail view in FIG 1 can recognize. In this way, rotary movements of the transmission part 4 are converted into the linear adjustment movements of the adjustment element 1 or locking element.

For this purpose, the electric motor 2 has an output worm on its output shaft, which in turn meshes with a ring gear of the transmission part 3 . The transmission part 3 is equipped with a worm on the output side, which in turn engages in a toothing of the further transmission part 4 and in this way causes it to rotate. Since the gear part 4 is coupled to the control element 5 in a torque-proof manner, the rotary movements of the gear part 4 are also transmitted to the control element 5 . The rotary movements of the control element 5 are now queried using the sensor 6. As a result of this, the sensor signals emitted by the sensor 6 and transmitted to a control unit (not shown) correspond to actuating movements of the actuating element 1 or the locking element.

The previously mentioned spring 7 is used in detail to act on the sensor 6, as can be seen from FIG 2 can understand. For this purpose, the spring 7 is interposed between the control element 5 and the sensor 6 . In fact, the spring 7 is located between a control contour 10a on a control disc 10 on the one hand and the sensor 6 on the other. The control disk 10 is also caused to rotate as a result of the rotation of the control element 5, namely by one in the 2 indicated axis A. As a result the spring 7 slides with a ramp 7a on the control contour 10a of the control disc 10 along. The spring 7 is an exemplary embodiment of a leaf spring 7 which is oriented with its narrow side S along the axial direction A defined by the axis A. In contrast, has the associated broad side B of the leaf spring 7 on the basis of 3 comprehensible orientation, which runs essentially in the same plane as the control disk 10 or the plane spanned by the control disk 10. The leaf spring 7 can be made of a metal strip, a plastic strip or combinations.

The control element 5 is coupled to the transmission part 4 or an associated drive pin 11 in a rotationally fixed but axially movable manner. The axial mobility results from the fact that the control element 5 is fitted with a receptacle or rotary receptacle 12 onto the drive pin 11 of the transmission part 4 and an anti-rotation lock 13 engaging in a receptacle also ensures the non-rotatable coupling. The anti-rotation device is a pin 13 which engages in the receptacle and couples the control element 5 to the transmission part 4 in a rotationally fixed manner. At the same time, however, movements in the axial direction A are permitted, namely of the control element 5 in relation to the gear part 4.

The spring or leaf spring 7 now ensures that the control element 5 is prestressed in the said axial direction A with the aid of the leaf spring 7, namely in the direction of a stop 14 for the control disk 10 of the control disk 10 perform movements in the axial direction A, however, the control disk 10 and thus the control element 5 are held in contact with the stop 14 so that the sensor 6 is decoupled from such movements in the axial direction A.

The leaf spring 7 is connected to a housing 15 at one end 7b. The housing 15 is a plastic housing which is set up and suitable for mounting the electric motor 2 and the transmission parts 3 , 4 and the control element 5 and also for accommodating the sensor 6 . In contrast, the other end 7c of the leaf spring 7 has an end stop or is designed as an end stop 7c. In fact, the end stop 7c is supported on a stop 16 of the housing 15. As a result of this, the leaf spring 7 according to the invention ensures that the control element 5 is decelerated or stopped as soon as a maximum path of the control element 5 has been completed. Consequently, the end stop 7c ensures that i. V. m. the stop 16 a travel limit of the control element 5 is reached and implemented.

The leaf spring 7 is also equipped with a stiffened area 7d, which is used to act on a switching cam of the sensor 6 designed as a switch or microswitch. This stiffened area 7d is characterized in that the leaf spring 7 is L-shaped or U-shaped in cross-section in the area. In addition, the leaf spring 7 is also equipped with an elastic area 7e. This elastic area 7e can change its shape in the manner of an accordion and has a wavy design for this purpose, in that the leaf spring 7 is curved in waves at this point. These waves and consequently the elastic area 7e come into play when the control element 5 is acted upon beyond the area defined by the end stop 7c in connection with the stop 16, in order to avoid any damage to the sensor 6.

Reference List

1

control element, locking element

2

electric motor

3, 4

transmission

5

control

6

sensor

7

spring or leaf spring

7a

ramp

7b

end of the leaf spring

7c

end stop

7d

stiffened area

7e

elastic area

8th

eccentric

9

U-shaped recess

10

control disc

10a

control contour

11

drive pin

12

Recording or shooting

13

Anti-rotation, pin

14

attack

15

Housing

16

attack

S

narrow side

A

axis, axial direction

B

broadside

QUOTES INCLUDED IN DESCRIPTION

This list of the documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• WO 2010/149426 A1 [0002]
• DE 102018114205 A1 [0003, 0004, 0029]
• CN202695855U[0005, 0008]
• DE 102009039652 A1 [0006]
• DE 102013008550 A1 [0006]

Claims (10)

Electromotive drive unit for motor vehicle applications, in particular locking unit for an electric charging device of a motor vehicle, preferably an electric or hybrid motor vehicle, with an electric motor (2) and optionally a downstream gearbox (3, 4), also with a movable actuating element (1) , and with a control element (5) and at least one spring (7) for acting on a sensor (6), characterized in that the spring (7) as between a control contour (10a) of the control element (5) and the sensor (6) arranged leaf spring (7) is formed, which slides with a ramp (7a) on the control contour (10a) to act on the sensor (6) along. drive unit after claim 1 , characterized in that the control element (5) is prestressed in the axial direction (A) by means of the leaf spring (7). drive unit after claim 1 or 2 , characterized in that the control element (5) is mounted on a drive pin (11) in a rotationally fixed and axially displaceable manner. Drive unit according to one of Claims 1 until 3 , characterized in that the control element (5) has an anti-rotation device (13) engaging in a receptacle of the drive pin (11). Drive unit according to one of Claims 1 until 4 , characterized in that the leaf spring (7) is connected at one end (7b) to a housing (15). Drive unit according to one of Claims 1 until 5 , characterized in that the leaf spring (7) at its other end (7c) has an end stop (7c) which interacts with a stop (16) on the housing (15) to limit travel. Drive unit according to one of Claims 1 until 6 , characterized in that the leaf spring (7) has a stiffened area (7d) for interaction with the sensor (6). drive unit after claim 7 , characterized in that the stiffened area (7d) is L-shaped or U-shaped in cross section. Drive unit according to one of Claims 1 until 8th , characterized in that the leaf spring (7) is aligned with its narrow side (S) along the axial direction (A) and with its broad side (B) predominantly at the same level as a plane spanned by the control disc (10) as part of the control element (5). . Drive unit according to one of Claims 1 until 9 , characterized in that the leaf spring (7) in the axial direction (A) has an elastic region (7e) which changes shape like an accordion.

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