Drive group for an assembly of a vehicle, in particular a vehicle seat, which assembly can be adjusted in various ways by electric motor, and an assembly of this kind

The drive group with adaptable motor shaft lengths and worm designs addresses the challenge of varying adjustment needs in vehicle seats, achieving a compact and cost-effective solution with precise motor control.

WO2025176622A1PCT designated stage Publication Date: 2025-08-28BROSE FAHRZEUGTEILE GMBH & CO KG
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Patent Information

Application Number
PCT/EP2025/054257
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-02-19
Filing Date
2025-02-18
Publication Date
2025-08-28

AI Technical Summary

Technical Problem

Existing drive assemblies for multi-position electric motor-adjustable vehicle components, such as vehicle seats, face challenges in adapting to different adjustment requirements while maintaining a common parts principle, particularly in terms of torque, adjustment speed, and installation space.

Method used

A drive group with multiple electric motors, each having identical motor assemblies, housings, and electronics modules, but differing in motor shaft length, worm design, and balancing mass position, allowing for tailored adaptation to specific requirements.

Benefits of technology

Enables a compact, space-optimized design with enhanced flexibility and precision in adjustment, maintaining low overall costs by using identical components with adaptable features.

✦ Generated by Eureka AI based on patent content.

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Abstract

The drive group is designed for an assembly of a vehicle, in particular for a vehicle seat (2), which can be adjusted in various ways by electric motor and comprises a plurality of differently designed electric motors (12A-12C) which each have: a motor assembly (14) having a stator (16) and a rotor (18); an electronic module (20); a housing (22); and a motor shaft (24) having a worm (26) attached thereto, the motor assembly (14), the electronic module (20) and the housing (22) being identical parts, and the electric motors (12A-12C) differing at least in terms of the length of the motor shafts (24). As a result, adaptation to different requirements in the case of an identical-parts principle is achieved.
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Description

[0001] Description

[0002] Drive group for a multiply electric motor adjustable assembly of a vehicle, in particular vehicle seat, as well as such an assembly

[0003] The invention relates to a drive assembly for a multi-position electric motor-adjustable vehicle component, in particular for a multi-position electric motor-adjustable vehicle seat. The drive assembly comprises several differently designed electric motors, each comprising a motor assembly with a stator and rotor, an electronic module, a housing, and a motor shaft with a worm gear mounted thereon. The motor assemblies, the electronic modules, and the housings of the various electric motors in the drive assembly are identical parts.

[0004] Such a drive group, referred to as an activator group, can be found, for example, in DE 10 2023 200 395 A1.

[0005] Specifically for vehicle seats, differently designed electric motors are used for different adjustment movements, which are adapted to the respective requirements of the respective adjustment movement, such as the required torque, adjustment speed, etc., or to different installation space requirements. The different adjustment movements include, in particular, backrest adjustment, longitudinal adjustment, and seat height adjustment.

[0006] The principle of using common parts for key components in the variously designed electric motors keeps overall costs low. To adapt the electric motors to different requirements, they are typically connected to gear assemblies of different designs.

[0007] Based on this, the invention is based on the object of specifying a drive group and a multi-electromotor adjustable assembly with such a drive group, wherein the adaptation to different requirements is improved while maintaining the principle of identical parts.

[0008] The object is achieved according to the invention by a drive group for a vehicle assembly that can be adjusted multiple times by an electric motor, in particular for a vehicle seat that can be adjusted multiple times by an electric motor, wherein the drive group has a plurality of differently designed electric motors, each of which has a motor assembly with a stator and rotor, an electronics module, a housing and a motor shaft with a worm attached to the worm, in particular to a protruding section of the motor shaft. The motor assembly, the electronics module and the housing are identical parts. With a view to particularly suitable adaptation to the different requirements of the various electric motors in the drive group, the electric motors, i.e. at least two electric motors, differ in the length of their motor shafts. The motor shaft is therefore not considered to be a component of the otherwise identical motor assembly.

[0009] The object is further achieved according to the invention by an assembly for a vehicle which is multiply adjustable by an electric motor and for this purpose has a plurality of adjustment mechanisms each driven by an electric motor, wherein the differently designed electric motors of the drive group are used for the various adjustment mechanisms.

[0010] The assembly is in particular a vehicle seat.

[0011] This therefore comprises the assembly with at least two electric motors. In a preferred embodiment, the vehicle seat preferably comprises more than two, in particular three, or even more than three electric motors.

[0012] In particular, the vehicle seat has a first electric motor for a tilt adjustment mechanism, as well as further, in particular different, electric motors for a longitudinal adjustment mechanism and for a height adjustment mechanism. These additional electric motors are also referred to below as second electric motors.

[0013] These several, preferably at least three electric motors differ in at least one of the features explained in more detail below, in particular the length of the motor shaft, the position of a balancing mass or the design of a worm.

[0014] While in the known drive assemblies based on the common parts principle, the motor shaft is an integral part of the same electric motor, in this case, the length of the motor shaft is specifically adapted to the different requirements. This is based on the consideration that a particularly compact and space-optimized design is often a key requirement. The variability of the motor shaft length therefore provides an additional degree of design freedom while simultaneously maintaining the common parts principle. The length of the motor shaft opens up further degrees of freedom, especially in conjunction with differently designed worm gears.

[0015] In a preferred development, the at least two electric motors therefore also differ with regard to the design of the worm, which is attached to the motor shaft, specifically on the protruding section of the motor shaft. In particular, the worms have different lengths and / or different pitches. In particular, the combination of motor shafts of different lengths with differently designed worms enables new degrees of design freedom and adaptations to different requirements, such as, for example, a particularly compact, short design if necessary. Overall, the different worms allow the motor characteristics to be suitably adjusted and adapted to the requirements, for example with regard to an adjustment speed and / or torque.

[0016] When reference is made to identical parts in this context, this refers to components or assemblies that are identical at least in terms of size, shape, and electrical / electronic properties, i.e., they do not differ with regard to the parameters just mentioned. Furthermore, all components of these identical parts are preferably identical (except for possible manufacturing and production tolerances).

[0017] The motor assembly comprises at least one stator assembly and one rotor assembly, which are referred to below as stator or rotor. They are arranged concentrically to one another and extend along a rotational axis in a longitudinal direction of the electric motor. At least one of these two assemblies (stator / rotor) has electrical coils that are suitably energized in a conventional manner. The other of these assemblies, in contrast, has, for example, permanent magnets. In a preferred embodiment, the rotor is arranged around the stator, in particular in the manner of a rotor bell into which the stator is immersed.

[0018] The motor assembly and the entire electric motor are preferably designed as a so-called BLDC (brushless direct current) motor. Such electric motors are characterized, among other things, by good controllability and high positioning accuracy. They are therefore particularly suitable for electric motor-driven adjustment drives, where the most precise approach to different adjustment positions is essential, even during repeated adjustment processes, as is the case with a vehicle seat, for example.

[0019] The rotor is generally connected in a rotationally fixed manner to the motor shaft, which runs along a longitudinal axis, in particular a central longitudinal axis, which also defines the axis of rotation. The motor shaft is mounted at least via one bearing, preferably via several spaced-apart bearings, in particular in the stator or, if necessary, alternatively or additionally also in the housing. The motor shaft preferably extends through the stator and rotor. Generally, the motor shaft projects forward in the longitudinal direction with its section beyond the motor assembly and / or the housing. The worm gear is mounted on this protruding section. Furthermore, this protruding section together with the worm gear usually drives a gear, which then ultimately interacts with the component to be adjusted of the multi-electromotor adjustable assembly, in particular the vehicle seat.

[0020] The control of the electrical coils and the motor assembly as a whole is carried out using the electronic module, which is therefore electrically connected to the coils in a suitable manner.

[0021] The motor assembly, i.e., the stator and rotor, are housed in the housing. The housing has a suitable receiving area for the stator and rotor. In particular, the housing forms a front-facing, particularly pot-shaped receiving area into which the motor assembly, specifically the rotor bell with the stator located therein, is inserted. This receiving area is open at the front, for example, so that the motor assembly is not covered by a housing cover, but is freely accessible.

[0022] Preferably, the electronics module is also accommodated in the housing. The housing can therefore also be referred to as an electronics housing. The electronics module is, in particular, a printed circuit board with electronic components mounted thereon. As mentioned, this electronic assembly is electrically connected to the motor group and can also be connected to a power supply and, if necessary, additionally to a control line. When installed, it is connected and, in particular, connected to a control unit.

[0023] In a practical embodiment, a balancing mass is attached to the motor shaft, with the electric motors, i.e., at least two of the electric motors, differing in terms of the position of the balancing mass on the motor shaft. Therefore, the balancing masses are positioned at different distances from the motor assembly in the different variants. Their longitudinal positioning on the motor shaft therefore varies.

[0024] Balancing masses are generally used to balance any imbalance in the rotating components of the respective electric motor. The balancing mass is usually a ring-shaped mass element mounted on the motor shaft. Its diameter is therefore necessarily larger than that of the motor shaft. The balancing mass is attached to the motor shaft, specifically to the protruding section of the motor shaft. The different positions of the balancing mass allow the specific, individual requirements of the various electric motors in the drive group to be taken into account. Especially in combination with the different lengths of the motor shaft, a very compact, short version can be achieved if necessary.

[0025] Generally, the balancing mass is positioned as far away from the motor assembly as possible, as this enables particularly efficient balancing. In addition to the balancing mass, the worm gear is also generally located on the protruding portion of the motor shaft.

[0026] In a preferred embodiment, the balancing mass is placed on a side of the worm gear facing away from the motor assembly. This ensures that the balancing mass is positioned as far away from the motor assembly as possible. This is particularly important for a design variant with a short motor shaft.

[0027] According to a preferred alternative embodiment, the balancing mass is positioned on the side of the worm gear facing the motor assembly, i.e. the balancing mass is arranged between the worm gear and the motor assembly. This design variant is particularly important in conjunction with a longer motor shaft, as it achieves efficient balancing through the greatest possible distance between the balancing mass and the motor assembly and, at the same time, a design is achieved in which the worm gear is positioned at a front end of the motor shaft, with the motor shaft, together with the worm gear, inserting it into a gearbox. With this design variant, the respective electric motor, with the motor shaft and the worm gear leading, can therefore be easily inserted longitudinally into a prefabricated gearbox assembly.

[0028] In a practical embodiment, the electric motors therefore further differ with regard to the longitudinal position sequence of the worm gear and the balancing mass. This means that in a first electric motor, the balancing mass is arranged on the side of the worm gear facing away from the motor assembly, while in a second electric motor, the balancing mass is arranged on the side of the worm gear facing the motor assembly, and thus between the worm gear and the motor assembly.

[0029] Preferably, the first electric motor is an electric motor for seat longitudinal adjustment.

[0030] The second electric motor is preferably an electric motor for tilt adjustment or height adjustment.

[0031] In a preferred embodiment, the screw of the first electric motor is also shorter than that of the second electric motor.

[0032] Preferably, the length of the motor shaft of the first electric motor is shorter than that of the second electric motor.

[0033] In particular, the combination of a shorter screw with a shorter motor shaft enables a particularly compact design.

[0034] This different positioning of the balancing mass generally enables a variety of installation situations. As already described at the beginning, the motor assembly has a rotor and a stator, wherein in a preferred embodiment the rotor has a rotor bell which is rotationally connected to the motor shaft and in which the stator is accommodated. This rotor bell is accommodated in particular in the aforementioned, cup-shaped receptacle on the front side of the housing, which is preferably open towards the front in the longitudinal direction. In the present case, the term rotor bell or bell-shaped is understood to mean an approximately cup-shaped design with a typically cylindrical geometry, wherein the rotor bell has a peripheral wall in the manner of a cylinder wall and is closed at one end by a base. Only the motor shaft passes through this end side and is preferably fastened to the base in a rotationally fixed manner.The motor shaft projects from this rotor bell in the longitudinal direction with its protruding section.

[0035] According to a preferred embodiment, the drive group comprises at least three differently designed electric motors. The drive group preferably comprises, for example, two electric motors that are constructed in accordance with the previously described second electric motor and that preferably differ from one another, particularly with regard to the design of the worm and / or the length of the motor shaft. Furthermore, the drive group comprises an electric motor that is constructed in accordance with the previously described first electric motor.

[0036] An embodiment of the invention is explained in more detail below with reference to the figures. These show

[0037] FIG 1 is a perspective view of a frame of a vehicle seat as a multi-electromotor adjustable assembly,

[0038] FIG 2 is a perspective exploded view of an electric motor,

[0039] FIG. 3A is a perspective exploded view of a stator and rotor with motor shaft with worm and balancing mass mounted thereon, FIG. 3B is the components according to FIG. 3A in an assembled state, FIG. 4 is a cross-sectional view through an assembly similar to the assembly shown in FIG. 3B according to a first variant for a first electric motor, and

[0040] FIG 5 is a cross-sectional view of the assembly shown in FIG 3B according to a second variant for a second electric motor.

[0041] In the figures, parts with the same function are provided with the same reference symbols.

[0042] FIG. 1 shows a frame of a vehicle seat 2 that is adjustable in multiple positions by an electric motor. The vehicle seat 2 has a backrest 4, a seat part 6, and, in the exemplary embodiment, an optional leg rest 7 that is adjustably arranged on the seat part 6. The backrest 4 is adjustable in its inclination relative to the seat part 6, and the vehicle seat 2 as a whole is longitudinally adjustable along rails 8, via which it is connected to the body. Furthermore, the seat part 6 is height-adjustable in the exemplary embodiment.

[0043] For each of these adjustment movements, a suitably designed adjustment mechanism 10A - 10C and an associated electric motor 12A - 12C are assigned. Each electric motor 12A - 12C is typically connected to the respective adjustment mechanism 10A - 10C via a gear mechanism (not specified here) to transmit the adjustment movement.

[0044] The adjustment mechanism 10A with its associated electric motor 12A serves to adjust the longitudinal position of the seat part 6 (hidden in FIG. 1 and therefore not visible). This electric motor 12A is also referred to below as the first electric motor.

[0045] The adjustment mechanism 10B with associated electric motor 12B serves to adjust the height of the seat part 6 and the adjustment mechanism 10C with associated electric motor 12C serves to adjust the inclination of the backrest 4. The electric motors 12B and 12C have - as will be described in more detail below - at least a comparable structure and are therefore also referred to as a second electric motor.

[0046] The basic structure of each electric motor is explained in more detail with reference to FIG. 2 and FIGS. 3A, 3B using such a second electric motor 12B.

[0047] This has a motor assembly 14 with a stator assembly and a rotor assembly, these being referred to here briefly as stator 16 and rotor 18. The electric motor 12B also has an electronics module 20, a housing 22 and a motor shaft 24. The motor shaft 24 and the entire electric motor 12B extend along a rotation axis R in the longitudinal direction L. In the exemplary embodiment, the motor shaft 24 extends counter to the longitudinal direction L into the housing 22. A sensor ring magnet 25 is also shown at the end of the motor shaft. The motor shaft 24 is generally connected to the rotor 18 in a rotationally fixed manner. It is usually rotatably mounted on the stator 16 via at least one bearing. In the longitudinal direction L, the motor shaft 24 has a section 24A that protrudes beyond the motor assembly 14 and thus also beyond the housing 22. A worm 26 and a balancing mass 28 are attached to this section 24A.

[0048] In the exemplary embodiment, the rotor 18 has a rotor bell 30, which forms a type of housing into which the stator 16 is inserted. Several electrical coils are arranged circumferentially on the stator 16. Furthermore, it has connections for control lines for controlling the motor assembly 14. These are suitably connected to the electronics module 20 in the assembled state. The rotor bell 30 is designed like a pot-shaped housing and has a cylindrical peripheral wall, which is closed on one end by an end wall forming a base, with the motor shaft 24 passing through this end wall. Permanent magnets are typically attached to the inside of the peripheral wall. The motor shaft 24 is connected in a rotationally fixed manner to the rotor 18 and in particular to the rotor bell 30. The stator 16, in turn, is preferably rotationally fixedly connected to the housing 22.It has a central passage through which the motor shaft 24 is guided in the exemplary embodiment.

[0049] The housing 22 accommodates the motor assembly 14. In the exemplary embodiment, the motor housing 22 has a cylindrical and, in particular, pot-shaped receiving space on its front end, into which the motor assembly 14 is inserted.

[0050] The electronics module 20 is, in particular, a printed circuit board with electronic components mounted thereon. The electronics module 20 is mounted and accommodated in a rear portion of the housing 22, thus downstream of the motor assembly 14. The housing 22 has a cover 32, which can be reversibly closed, for example, and which extends over the printed circuit board.

[0051] In a manner not shown in detail here, a gear is arranged in the longitudinal direction L at the front end of the respective electric motor 12A - 12C, at least in the assembled state, i.e. when the electric motors 12A - 12C are installed in the vehicle seat 2, into which gear the motor shaft 24 penetrates together with the worm 26 and the balancing mass 28.

[0052] The various electric motors 12A - 12C are designed as identical parts and differ only with regard to the length of the motor shaft 24, in particular with regard to the length of the protruding section 24A, and / or with regard to the position and design of the worm 26 and / or with regard to the position of the balancing mass 28 on the motor shaft 24. In particular, the electric motors 12A - 12C differ with regard to the sequence of the balancing mass 28 and the worm 26 on the protruding section 24A.

[0053] FIG. 4 shows a first type of motor assembly 14 with motor shaft 24, which is part of the previously described first electric motor 12A. This type is essentially characterized by the fact that the balancing mass 28 is arranged on the side of the worm 26 opposite the motor assembly 14. In this embodiment, the worm 26 is therefore mounted between the balancing mass 28 and the motor assembly 14 / housing 22.

[0054] FIG. 5 shows a second type of motor assembly 14 with motor shaft 14, which is part of the previously described second electric motors 12B, 12C. This second type is essentially also characterized by the fact that the balancing mass 28 is mounted between the worm 26 and the motor assembly 14 / housing 22.

[0055] As can be seen in particular from a comparison of FIG 4 with FIG 5, the two electric motors 12A, 12B, 12C, which are only shown in sections, differ not only in the different sequence of worm 26 and balancing mass 28, but also in terms of the length of the motor shaft 24, in particular of the protruding section 24A, and also in the length and in particular the pitch of the worm 26. In the second type shown in FIG 5, the motor shaft 24 and also the worm 26 are longer than in the first type shown in FIG 4.

[0056] As previously described, the two electric motors 12B, 12C for the height adjustment and for the inclination adjustment of the backrest 4 are preferably designed according to the second type. These two electric motors 12B, 12C preferably differ with regard to the length of the motor shaft 24 and / or the design of the worm 26. List of reference symbols

[0057] 2 vehicle seats

[0058] 4 backrest

[0059] 6 Seat part

[0060] 7 Leg rest

[0061] 8 rails

[0062] 10A-C adjustment mechanism

[0063] 12A-C electric motor

[0064] 14 Engine assembly

[0065] 16 Stator

[0066] 18 Rotor

[0067] 20 Electronic module

[0068] 22 housings

[0069] 24 Motor shaft

[0070] 24A section

[0071] 25 Sensor ring magnet

[0072] 26 snail

[0073] 28 Balancing mass

[0074] 30 rotor bell

[0075] 32 lids

[0076] R rotation axis

[0077] L longitudinal direction

Claims

Claims 1 . Drive group for a multiply electric motor adjustable assembly of a vehicle, in particular for a vehicle seat (2), with several differently designed electric motors (12A - 12C), each having a motor assembly (14) with a stator (16) and rotor (18), an electronics module (20), a housing (22) and a motor shaft (24) with a worm (26) attached thereto, wherein the motor assembly (14), the electronics module (20) and the housing (22) are identical parts, characterized in that the electric motors (12A - 12C) differ in the length of their motor shafts (24).

2. Drive group according to the preceding claim, wherein the worms (26) of the differently designed electric motors (12A - 12C) differ, in particular with regard to their length.

3. Drive group according to one of the preceding claims, wherein a balancing mass (28) is mounted on the motor shaft (24) and the electric motors (12A - 12C) differ with regard to the position of the balancing masses (28).

4. Drive group according to the preceding claim, wherein the balancing mass (28) is arranged at least in one of the electric motors (12A - 12C) on the side of the worm (26) facing away from the motor assembly (14).

5. Drive group according to one of the two preceding claims, wherein the balancing mass (28) is arranged at least in one of the electric motors (12A - 12C) on the side of the worm (26) facing the motor assembly (14).

6. Drive group according to one of claims 3 to 5, wherein in a first electric motor (12A) the balancing mass (28) is arranged on the side of the worm (26) facing away from the motor assembly (14) and wherein in a a second electric motor (12B, 12C) the balancing mass (28) is arranged on the side of the worm (26) facing the motor assembly (14).

7. Drive group according to the preceding claim, wherein the worm (26) of the first electric motor (12A) is shorter than that of the second electric motor (12B).

8. Drive group according to one of the preceding claims, wherein the rotor (18) has a rotor bell (30) in which the stator (16) is received.

9. Drive group according to one of the preceding claims, which has at least three differently designed electric motors (12A - 12C).

10. An assembly for a vehicle which is multiply adjustable by an electric motor and for this purpose has a plurality of adjustment mechanisms (10A - 10C) each driven by an electric motor (12A - 12C), wherein the differently designed electric motors (12A - 12C) of the drive group according to one of the preceding claims are used for the various adjustment mechanisms. 11 . Assembly according to the preceding claim, which is a vehicle seat (2).

12. Assembly according to one of the two preceding claims, which has a first electric motor (12A) for an inclination adjustment mechanism and further, in particular mutually different electric motors (12B, 12C) for a longitudinal adjustment mechanism and for a height adjustment mechanism, wherein at least two and preferably all electric motors (12B, 12C) differ in at least one of the features length of the motor shaft (24), position of the balancing mass (28) or design of the worm (26).

Citation Information

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