WO2022117151A1

WO2022117151A1 - Electromotive drive unit for motor vehicle applications

Info

Publication number: WO2022117151A1
Application number: PCT/DE2021/100957
Authority: WO
Inventors: Tim SONNENSCHEIN; Benjamin DJEDOVIC
Original assignee: Kiekert Ag
Priority date: 2020-12-02
Filing date: 2021-12-02
Publication date: 2022-06-09
Also published as: DE102020132027A1

Abstract

The invention relates to an electromotive drive unit for motor vehicle applications, in particular a locking unit for an electrical charging device of a motor vehicle. The drive unit comprises an electric motor (2) and optionally a transmission (3, 4) mounted downstream thereof. The invention further relates to a displaceable actuating element (7) and moreover to a control element (5) as well as to at least one spring (7) for impinging a sensor (6). According to the invention, the spring (7) is designed as a leaf spring (7) arranged between a control contour (10a) of the control element (5) and the sensor (6), which glides along with a ramp (7a) on the control contour (10a) for impinging the sensor (6).

Description

description

Electromotive drive unit for motor vehicle applications

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 of 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, an identification of the operator and an authorization check using an identification signal usually takes place before such a loading process, as is basically described in WO 2010/149426 A1.

Details of an electromotive drive unit designed in this context as a locking unit i. V. m. the associated electrical charging device are described by way of example in DE 10 2018 1 14 205 A1 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 are used, as described in detail in DE 10 2018 114 205 A1, which has already been described above and is referred to.

A generic electromotive drive unit has become known from CN 202695855 U. 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.

DE 10 2009 039 652 A1 has disclosed other spring arrangements which i. V. m. serve a control cam to act on a switch. DE 10 2013 008 550 A1 shows something similar. 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 according to 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 further developing such a drive unit in such a way that damage-free operation with high resolution is ensured.

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. Basically, the question in question Leaf spring 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 in the same plane as a plane spanned by a control disk 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 the control contour has and the control contour in turn has areas of different axial extent, the ramp of the leaf spring in contact with the control contour is deflected by this to a greater or lesser extent. 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. Due to the fact that the eccentric on the gear part engages in the U-shaped receptacle of the actuating element, rotary movements of the associated gear 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 mentes may occur when the electric motor and, consequently, the downstream gearbox change direction.

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 keeps mechanical load peaks away from the sensor and also any tilting movements transmitted to the sensor, which 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.

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

1 shows the electromotive drive unit in a perspective overview,

FIG. 2 shows the object according to FIG. 1 in a detailed view in the area of the control element including the sensor and leaf spring,

Fig. 3 shows the object of FIG. 2 in a view from above and

4A, 4B the actuation of the sensor by the interposed leaf spring in detail.

In the figures, an electromotive drive unit for motor vehicle applications is shown. With the aid of the electromotive drive unit, an actuating element 1 shown in FIG. 1 is moved in the linear direction shown there by a double arrow. In the exemplary embodiment and not by way of limitation, the electromotive drive unit around 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 corresponding topological arrangement is presented by way of example in the previously described DE 10 2018 114 205 A1 of the applicant, to which express reference is 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 3, 4 works on the movable actuating element 1. In particular from FIGS. 2 and 3 it can be seen 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. 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 understood from FIG. 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 rotated as a result of the rotation of the control element 5, specifically about an axis A indicated in FIG. 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, the associated broad side B of the leaf spring 7 has an orientation that can be understood with reference to FIG. 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 will come into contact with the stop 14 is held 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 gears

5 control

6 sensors

7 spring or leaf spring

7a ramp

7b end of leaf spring

7c end stop

7d stiffened area

7e elastic area

8 eccentrics

9 U-shaped recess

10 control disk

10a control contour

11 drive pin

12 recording or rotary recording

13 Anti-rotation pin

14 stop

15 housing

16 stop

S narrow side

A axis, axial direction

B broadside

Claims

patent claims

1. Electromotive drive unit for automotive 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 (2) and optionally a downstream transmission (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), d a r c h e k e n n z e i c h n e t 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.

2. Drive unit according to claim 1, characterized in that the control element (5) is prestressed in the axial direction (A) by means of the leaf spring (7).

3. Drive unit according to claim 1 or 2, characterized in that the control element (5) on a drive pin (11) is rotatably and axially displaceably mounted.

4. Drive unit according to one of claims 1 to 3, characterized in that the control element (5) has an anti-rotation device (13) engaging in a receptacle of the drive pin (11).

5. Drive unit according to one of claims 1 to 4, characterized in that the leaf spring (7) is connected with its one end (7b) to a housing (15).

6. Drive unit according to one of Claims 1 to 5, characterized in that the leaf spring (7) has an end stop (7c) at its other end (7c). has, which interacts with a stop (16) on the housing (15) to limit travel.

7. Drive unit according to one of claims 1 to 6, characterized in that the leaf spring (7) has a stiffened area (7d) for interaction with the sensor (6).

8. Drive unit according to claim 7, characterized in that the stiffened area (7d) is L-shaped or U-shaped in cross section.

9. Drive unit according to one of claims 1 to 8, characterized in that the leaf spring (7) with its narrow side (S) along the axial direction (A) and with its broad side (B) predominantly level with one of the control disc (10) as Part of the control (5) spanned level is aligned.

10. Drive unit according to one of claims 1 to 9, characterized in that the leaf spring (7) in the axial direction (A) has an elastic region (7e) which changes shape like an accordion.