Drive device having a brushless DC motor

Abstract

The proposed solution relates to a drive device (1A, 1B), in particular for a vehicle seat (2), having a brushless DC motor, BLDC motor (10A, 10B), and a control unit (11A, 11B), wherein the control unit (11A, 11B) is configured: in a normal operating mode of the control unit (11A, 11B), by means of communication with a communication node (30, 11B) via an interface (110) of the control unit (11A, 11B), to receive control commands (410) and to control the BLDC motor (10A, 10B) on the basis of the received control commands (410); to recognize a disturbance of the communication with the communication node (30, 11B) via the interface (110) and / or a predefined input, and to switch to a maintenance mode in reaction to the recognized disturbance and / or the predefined input; and in the maintenance mode, to control the BLDC motor (10A, 10B) independently of communication with the communication node (30, 11B).

Description

[0001] Drive device with a brushless DC motor

[0002] Description

[0003] The proposed solution relates to a drive device, a vehicle seat with such a drive device, a method for controlling a drive device and a computer-readable storage medium.

[0004] Vehicle seats are typically adjustable, e.g. to enable different seat users to achieve a comfortable seating position and to be adapted to different space conditions. For example, a vehicle seat can be mounted in a vehicle so that it can be adjusted lengthwise by means of a longitudinal adjustment device in order to enable different seating positions along the vehicle's longitudinal axis, a vehicle seat can be adjustable by means of a height adjustment device in order to adjust the seat height, and in a vehicle seat the inclination of a backrest relative to a seat part can be adjustable, to name just a few examples. Manual or motorized drive devices can be provided to make such adjustments. Using motorized drive devices, the settings can be made easily, e.g. by pressing buttons, or even completely automatically.Until now, DC motors with sliding contacts were generally used in motor drive devices, but in recent times it has become apparent that brushless DC motors, or BLDC motors, are particularly advantageous due to their precision and size. However, if, for example, a defect occurs that prevents control commands from being sent to the drive device with a BLDC motor, it is no longer easily possible to effect an adjustment. While with DC motors with sliding contacts an external DC voltage can typically simply be connected to activate the motor, this is typically not possible in a similarly simple way with a BLDC motor, as a suitable AC voltage would first have to be generated from the DC voltage, which is typically what the control commands are needed for. This can, for example, make maintenance more difficult.

[0005] The task is to improve the handling of a drive device with a BLDC motor.

[0006] This object is achieved by an article having the features of claim 1.

[0007] According to this, a drive device is specified, in particular for a vehicle seat, comprising a brushless DC motor, BLDC motor, and a control unit, wherein the control unit is configured to: receive control commands in a normal operating mode of the control unit by communicating with a communication node via an interface of the control unit and to control the BLDC motor based on the received control commands; detect a disruption in the communication with the communication node via the interface and / or detect a predefined input and switch to a maintenance mode in response to the detected disruption and / or the detected predefined input; and, in the maintenance mode, to control the BLDC motor independently of communication with the communication node.

[0008] In this way it is possible, for example, in the event of a failure of the communication node from which the control unit receives the control commands in normal operating mode, for the BLDC motor to still be activatable. This means that an adjustment device can still be adjusted despite the aforementioned defect. For example, in the case of a vehicle seat with the drive device, the vehicle seat can be brought into a position in which maintenance is possible or easier. For example, removing a vehicle seat is often only possible if the vehicle seat is set in a certain position, since this is the only way to access the screws with which the vehicle seat is mounted to a vehicle floor, to name just one example. The drive device described thus allows improved handling and thus, for example, easier maintenance of a vehicle seat with the drive device.Communication can be unidirectional or bidirectional. The interface can be a physical (hardware) interface or a software interface. The communication node can be a so-called master, while the control unit can be a so-called slave. Therefore, the communication node does not need to be active, connected, functional, or even present to switch to maintenance mode.

[0009] The interface can be configured for communication via a bus system. This enables simple connection and efficient communication. Furthermore, many vehicles and other applications often already have bus systems installed that can be used for this purpose.

[0010] The bus system can be, for example, a LIN bus or a CAN bus. Such bus systems are efficient and proven in practice, and are often already available, especially in vehicles.

[0011] The control unit can be configured to detect a timeout and / or an impermissible level (e.g., a voltage level present at the interface) through communication via the interface. This makes it easy to detect communication disruptions.

[0012] For example, the control unit is configured to detect a communication interruption as a disruption of communication via the interface, e.g., if no control command is received by the control unit for a predetermined period of time and / or if no response from the communication node to a message sent by the control unit is received by the control unit for a predetermined period of time. This makes it easy to detect that the vehicle seat is no longer (or no longer) normally controllable.

[0013] The control unit can be configured to read the control commands from messages received through communication via the interface, each having a predetermined format (e.g., a predetermined bit length and / or a predetermined division into a header and a data portion). For example, the control unit is configured to receive messages, each with a header and a data portion, through communication via the interface. The control unit can also be configured to read a respective control command from a respective data portion. This makes it possible to receive relatively complex control commands, allowing convenient and fast configuration.

[0014] The control unit can be configured to detect at least one control signal. The control unit can also be configured to control the BLDC motor in maintenance mode based on the detected control signal. This allows, for example, maintenance personnel to continue controlling the BLDC motor even in the event of a fault.

[0015] In one possible embodiment, the predefined input specifies the control signal. For example, the control unit knows several possible predefined inputs, and by detecting a specific one of the several possible inputs, the control unit recognizes which of several possible types of control of the BLDC motor should be performed (e.g., the direction of rotation and / or a position to be approached).

[0016] For example, the control unit is further configured to control the BLDC motor in maintenance mode based on the at least one control signal such that the BLDC motor performs a defined number of revolutions and / or causes an adjustment to a predetermined position, in particular to a stop. This allows for a simple adjustment required in the event of a malfunction.

[0017] The control unit can be configured to receive the at least one control signal by a method other than communication with the communication node. The control commands and the control signal can, in particular, be different from one another. For example, the control unit receives the control signal by a method other than via the interface.

[0018] The control unit can be configured to receive the at least one control signal wirelessly. This allows for particularly simple handling.

[0019] The control unit is configured, for example, to receive the predefined input and / or the at least one control signal as a potential applied to at least one pin of the control unit, as a current flow through at least one pin, and / or as an electrical connection between two pins of the control unit. Such a solution is particularly robust. The pin(s) can be covered by a connector connected to the interface and / or a housing and / or a break-off cover. This prevents misuse and accidental actuation. Furthermore, the pin(s) can be protected from contamination.

[0020] Furthermore, the control unit can be configured to detect the predefined input and / or the at least one control signal as an excess of a predetermined (maximum) voltage (e.g. 16 V) and / or as a fall below a predetermined (minimum) voltage (e.g. 9 V). In this way, the input or the control signal can be entered in a particularly simple and reliable manner. An unusual voltage can therefore serve as the predefined input. The excess or fall below can be determined, for example, at a supply pin of a supply voltage (or at a pin of the interface). For example, the predefined input can be that the control unit detects that a pin of the interface is connected to ground potential.

[0021] The control unit can be configured to detect the predefined input and / or the at least one control signal based on a predetermined duration and / or a predetermined sequence. This can prevent incorrect operation. Furthermore, multiple control signals can be distinguished in this way. The control unit can assign control patterns for controlling the BLDC motor to one or more predefined control signals in a predetermined manner. For example, the control unit is configured to detect the predefined input in the form of a predefined Morse code (e.g., based on exceeding or falling below a predetermined voltage threshold).

[0022] The control unit can be configured to reduce the speed of the BLDC motor in maintenance mode compared to normal operating mode. This can reduce the risk of pinching, for example, a foot.

[0023] The control unit can further be configured to activate the BLDC motor intermittently and / or at an imposed frequency in the audible range during maintenance mode. This allows a user or maintenance personnel to directly detect that the drive device is in maintenance mode.

[0024] In maintenance mode, the direction of rotation of the BLDC motor can be predefined. This allows for particularly simple control. Alternatively, the direction of rotation can be set via the control signals and / or the predefined input. Furthermore, the direction of rotation can be reversed each time the predefined input is received.

[0025] The drive device can comprise several BLDC motors controlled by the control unit. This allows for a wide range of adjustments with a simple design.

[0026] According to one aspect, a vehicle seat is provided with at least one drive device according to any embodiment described herein. The drive device can be configured to adjust at least one adjustment device of the vehicle seat. Regarding the advantages, reference is made to the above information regarding the drive device.

[0027] The at least one adjustment device can comprise a backrest inclination adjustment device for adjusting the inclination of a backrest of the vehicle seat, a seat height adjustment device for adjusting the seat height of a seat part of the vehicle seat, or a longitudinal adjustment device for adjusting the longitudinal position of at least the seat part. This enables a high level of comfort.

[0028] According to one aspect, a method for controlling a drive device with a brushless DC motor, BLDC motor, and a control unit is provided, in particular the drive device according to any embodiment described herein. The method comprises the following steps performed by the control unit: receiving, in a normal operating mode of the control unit and by communication via an interface of the control unit, control commands and controlling the BLDC motor based on the received control commands; detecting a disruption in the communication via the interface and switching to a maintenance mode in response to the detected disruption; and processing, in maintenance mode, at least one control signal and controlling the BLDC motor based on the at least one control signal. With regard to the advantages, reference is again made to the above information on the drive device.

[0029] According to one aspect, a computer-readable storage medium is provided on which instructions are stored which, when executed by a control unit of a drive device (in particular the drive device according to any embodiment described herein) with a brushless DC motor, BLDC motor, cause the control unit to perform the method described above. Regarding the advantages, reference is again made to the above information regarding the drive device.

[0030] The concept underlying the invention will be explained in more detail below with reference to the exemplary embodiments illustrated in the figures. They show:

[0031] Fig. 1 shows a vehicle seat with several adjustment devices;

[0032] Fig. 2 several components and a drive device of the vehicle seat according to

[0033] Fig. 1 ;

[0034] Fig. 3 shows several drive devices connected to a bus system;

[0035] Fig. 4 shows a control unit of the drive device according to Fig. 2;

[0036] Fig. 5 a message with a header and a data part, where in the data part a

[0037] control command is included;

[0038] Fig. 6 shows a method for controlling a drive device;

[0039] Fig. 7 a brushless DC motor designed as an internal rotor of the

[0040] Drive device according to Fig. 1 ; and

[0041] Fig. 8 a brushless DC motor designed as an external rotor of one of the

[0042] Drive devices according to Fig. 3.

[0043] Fig. 1 shows a vehicle seat 2 with a seat part 20 and a backrest 21. The backrest 21 is pivotally mounted on the seat part 20 about a pivot axis S by means of a backrest inclination adjustment device 22. For this purpose, the backrest inclination adjustment device 22 comprises a fitting arrangement 220 with, for example, two rotary or locking fittings.

[0044] The seat part 20 has a seat height relative to a vehicle floor FB along a vehicle height direction Z. The vehicle seat 2 can be mounted on the vehicle floor FB of a vehicle and is mounted as shown in Fig. 1. The seat part 20 (together with the backrest 21) can be adjusted in height by means of a seat height adjustment device 23. For this purpose, the seat height adjustment device 23 has a plurality of pivotable pivot arms 230 on which the seat part 20 is supported. The vehicle seat 2 further comprises a longitudinal adjustment device 24. The longitudinal adjustment device 24 allows a longitudinal adjustment of the vehicle seat 2 along a vehicle longitudinal direction X. By means of the longitudinal adjustment device 24, the seat part 20 and the backrest 21 can be moved together along the vehicle longitudinal direction X relative to the vehicle floor FB. The vehicle longitudinal direction X is oriented perpendicular to the vehicle height direction Z.The longitudinal adjustment device 24 comprises two pairs, each consisting of a rail that can be fixed to the vehicle floor FB and, in the example shown, is fixed, which can also be referred to as a floor rail 241, and a seat rail 240 that is displaceably mounted thereon along the vehicle's longitudinal direction X. The remaining vehicle seat 2 can be mounted on the seat rail 240 and is mounted in the example shown. The two pairs, of which only one is visible in the view in Fig. 1, are spaced apart from one another along a vehicle transverse direction. The vehicle transverse direction is oriented perpendicular to the vehicle's longitudinal direction X and perpendicular to the vehicle height direction Z. A stop 242 limits the displacement of the seat rail 240 relative to the floor rail 241, in the example shown, against further displacement rearward.

[0045] The adjustment devices 22, 23, 24 shown are examples; the vehicle seat 2 can comprise one, several, or all of the adjustment devices 22, 23, 24 and / or additional adjustment devices not shown. The adjustment devices 22, 23, 24 are each motor-adjustable.

[0046] Fig. 2 shows the seat rails 240 and floor rails 241 of the longitudinal adjustment device 24 as well as pivot arms 230 of the seat height adjustment device 23. Furthermore, Fig. 2 shows a drive device 1A.

[0047] The drive device 1A of the vehicle seat 2 comprises several brushless direct current motors, BLDC motors 10A, two of which are shown in Fig. 2. One of the BLDC motors 10A is provided for adjusting the longitudinal adjustment device 24. This drives the two seat rails 240 via a gear, so that they are displaced relative to the floor rails 241. Another of the BLDC motors 10A drives a spindle nut along a spindle to adjust the seat height adjustment device 23.

[0048] Furthermore, the drive device 1A comprises several control units 11A, 11B. Thus, a separate control unit 11A is provided for each of the BLDC motors 10A. These control units 11A are each arranged on the corresponding BLDC motor 10A; in the present case, these control units 11A each form a unit with the respective BLDC motor 10A. Furthermore, a seat control unit 11B is provided, which can be connected to a bus system of the vehicle and which is communicatively connected to the other control units 11A.

[0049] The seat control unit 11B receives control commands 410 via the connected bus system (explained in more detail below with reference to Fig. 5), which may relate to one or more of the BLDC motors 10A. For this purpose, the seat control unit 11B communicates with the control units 11A of the individual BLDC motors 10A and thus functions as a communication node. The control units 11A of the individual BLDC motors 10A each communicate with the seat control unit 11B, and it can be provided that the control units 11A of the individual BLDC motors 10A communicate via the seat control unit 11B with an external communication node 30 (see the explanations below regarding the communication node 30 in connection with Fig. 3).

[0050] At least one of the control units 11A, 11B is configured (in the present example, all of the control units 11A, 11B are configured) to receive control commands 410 in a normal operating mode of the control unit 11A, 11B by communicating with a communication node 30, 11B via an interface 110 of the control unit 11A, 11B and to control the respective BLDC motor 10A based on the received control commands 410.

[0051] Furthermore, the at least one control unit 11A, 11B (in this case, the control units 11A, 11B) is configured to detect a disruption in communication with the communication node 30 via the interface 110 and / or a predefined input and to switch to a maintenance mode in response to the detected disruption and / or the predefined input, and is configured to control the respective BLDC motor 10A, 10B in the maintenance mode independently of communication with the communication node 30.

[0052] The interfaces 110 each have a plurality of electrically conductive contacts. In this case, the interfaces 110 are each formed on a socket 117, into which a respective plug can be plugged. Communication via the respective interface 110 occurs according to a predefined communication protocol, for example, as explained below in connection with Fig. 3.

[0053] Fig. 3 shows a system with several (here two) drive devices 1B, which are communicatively connected to a communication node 30 via a bus system 3. This system according to Fig. 3 can be used in a vehicle seat, e.g., in the vehicle seat 2 according to Fig. 1, for example, to drive one or more of the adjustment devices 22, 23, 24.

[0054] The drive devices 1B each comprise a BLDC motor 10A, 10B, the structure of which is explained in more detail below with reference to Figs. 7 and 8. Furthermore, the drive devices 1B each have a control unit 11A, which is designed as explained above in connection with Fig. 2. In the example according to Fig. 3, however, no seat control unit is provided via which the control units of the individual BLDC motors 10B would be connected to an external communication node. Rather, it is provided that each of the control units 11A is connected directly to the bus system 3 with a cable 32. In each case, a connector 31 of the bus system 3 is connected, e.g. plugged in, to the respective interface 110 of the individual control units 11A.

[0055] In the example shown, bus system 3 is a LIN bus (Local Interconnect Network), but it could alternatively be another bus system, e.g., a CAN bus. Communication node 30 is a master in bus system 3, and each of the control units 11A is a slave in bus system 3.

[0056] The communication node 30 includes a clock generator 300. The communication node 30 generates a clock signal using the clock generator 300. The control units 11A are configured to receive the clock signal from the communication node 30 by communicating via the respective interface 110.

[0057] In normal operating mode, the control units 11A receive control commands via the bus system 3 from the communication node 30 and via the respective interface 110. The control commands can each specify a target position or a distance to be traveled. Furthermore, the control commands can each specify an adjustment speed and / or an adjustment direction. The control unit 11A interprets these control commands and controls the respective BLDC motor 10A accordingly. To this end, the control unit 11A generates a pulse width modulation (PWM) signal based on the respective control command. The PWM signal controls an inverter connected to coils of the respective BLDC motor 10A, causing it to rotate.

[0058] A rotation angle sensor 12 is provided to measure the rotation of a motor shaft of the respective BLDC motor 10A. The rotation angle sensor 12 is connected to the control unit 11A. Using the rotation angle sensor 12, the control unit 11A can determine the speed of the BLDC motor 10A. Alternatively or additionally, the rotation angle sensor 12 can be used to determine the distance traveled.

[0059] It should be noted that the system according to Fig. 3 could also have more than two drive devices 1 B or only one drive device 1 B instead of two drive devices 1 B.

[0060] Further details of the control unit 11A will now be described with reference to Fig. 4. The seat control unit 11B may comprise the same components, so the following explanations apply accordingly.

[0061] The control unit 11A comprises a storage medium 111 on which instructions are stored which, when executed by the control unit 11A (more precisely: by a processor arrangement 112 of the control unit 11A), cause the control unit 11A to carry out the method according to Fig. 6.

[0062] Furthermore, the control unit 11A includes the aforementioned interface 110. In this case, the interface is designed as a socket with several pins 113A-113D. The connector 31 of the bus system 3 can be plugged into some of the pins 113A-113D, in this case, for example, three pins 113B-113D.

[0063] By way of example, it is provided that a further pin 113A is concealed by a cover 115, which is connected to a housing 114 of the control unit 11A by a predetermined breaking point 118. This pin 113A is thus accessible by breaking off the cover 115. The control unit 11A is configured to receive the predefined input as a potential applied to this pin 113A (e.g., ground potential), an applied voltage, a current flowing via this pin 113A, and / or an electrical connection between two of the pins 113B, 113C of the control unit 11A. To put the control unit 11A into maintenance mode, the cover 115 can be broken off and the pin 113A connected to a voltage. Alternatively or in addition to the cover 115, it can be provided that the pin 113A, which can also be arranged at a distance from the interface 110, is only accessible after removing a housing shell of the housing 114.

[0064] Furthermore, it can be detected as a predefined input when a bridge is connected to pins 113A-113D. Furthermore, for example, in the case of the drive device according to Fig. 2, the seat control unit 11B can be provided with a positive or negative pole applied to two pins 113A-113D to move all BLDC motors 10A, 10B forward or upward or to a predefined maintenance position.

[0065] Furthermore, it can be provided that a keypad can input the predefined input using a predefined key combination via the interface 110. Furthermore, the individual control units 10A, 10B can exchange messages with each other via the bus system in order to also put each other into maintenance mode and / or to communicate control signals. One of the control units 10A, 10B can be configured as a master and send messages with control commands to one or more other control units 10A, 10B.

[0066] Furthermore, it can be provided that a connected push-button panel detects a missing master in the bus system 3 and switches itself from slave to master and controls the BLDC motors 10A, 10B.

[0067] Alternatively, it can be provided that the connector 31, when connected to the interface 110, covers that pin 113A so that it is not accessible and protected during normal operation.

[0068] In this case, the control unit 11A is configured to detect a communication interruption as a communication disruption via the interface 110. The communication interruption occurs, for example, due to a defect in the communication node 30 or its power supply, due to a defect in a cable 32 of the bus system 3, or due to the connector 31 being removed from the interface 110. A disruption can also be detected by a timeout (e.g., a predetermined period of time during which no message has been received) and / or an impermissible level (in particular, one outside a predefined range) present at the interface or at a supply pin.

[0069] The control unit 11A is thus configured to receive the control signal in a different way than through communication with the communication node 30.

[0070] Alternatively, it can be provided that a switch to maintenance mode occurs only upon a detected communication disruption via bus system 3, or only upon detecting the predefined input, or only upon a detected disruption and additionally a predefined input. Switching to maintenance mode can activate a servo mode. Furthermore, control unit 11A includes a clock generator 113. This can be configured much more simply than clock generator 300 of communication node 30, since control unit 11A receives the (more precise) clock pulse of clock generator 300 of communication node 30 via communication with communication node 30.

[0071] Furthermore, the control unit 11A includes a wireless interface 116 for communication via WLAN, Bluetooth, NFC, or the like. However, this is only an example, and the control unit 11A could also include only pin 113A or only the wireless interface 116. Via the wireless interface 116, the control unit 11A can (likewise) wirelessly receive the input(s) that trigger a switch to maintenance mode. This allows for particularly convenient input.

[0072] The control unit 11A receives a supply voltage (here a DC voltage) via a power supply connection A.

[0073] The respective 10A BLDC motor is connected to a motor terminal 119. PWM signals can be transmitted via the motor terminal 119 if the 10A BLDC motor includes the inverter. If the control unit 11A includes the inverter, a three-phase supply voltage, for example, is output to the 10A BLDC motor via the motor terminal 119.

[0074] To control the BLDC motor 10A in maintenance mode, the control unit 11A is configured to detect a control signal and to control the BLDC motor 10A in maintenance mode based on the at least one detected control signal. The predefined input comprises the control signal in the present example. The control unit 11A is configured to first be placed in maintenance mode and then to receive control commands in maintenance mode. In the present example, the control unit 11A is further configured to be able to interpret several different predefined control signals and to control the BLDC motor 10A differently in each case, e.g., to move to a specific position or in a specific direction.

[0075] For example, the control unit 11A controls the BLDC motor 10A in maintenance mode based on the at least one control signal such that the BLDC motor 10A executes a predefined number of revolutions and / or causes an adjustment to a predetermined position, in particular up to the stop 242. However, it could also be provided that the control unit 11A only recognizes a predefined input and, if this input is present, switches to maintenance mode and moves to a predefined maintenance position. In maintenance mode, a direction of rotation of the BLDC motor 10A can be fixed. Alternatively, the direction of rotation can be changed by detecting a newly entered input or can be adjustable by information in the input.

[0076] The control unit 11A can be configured to detect the predefined input as exceeding a predetermined voltage (e.g. < 9V or > 16V), e.g. at one of the pins 113A-113D and / or at the power supply terminal A. Alternatively or additionally, the control unit 11A can be configured to detect the predefined input based on a predetermined duration and / or a predetermined sequence (e.g. 5 times 1 s each with a 1 s pause each) with which a voltage (e.g. of a predetermined level) is applied to one of the pins 113A-113D and / or at the power supply terminal A. For example, information can be input to the control unit 11A by means of temporal coding, for example in the form of Morse code or PWM signals or the like. Furthermore, an analog input can be provided.

[0077] In order to increase safety, e.g. if an optional anti-pinch protection is not active in maintenance mode, the control unit 11 can be configured to reduce a speed of the BLDC motor 10A in maintenance mode compared to the normal operating mode and / or to activate the BLDC motor 10A intermittently and / or with an imposed frequency in the audible range (e.g. in the range from 100 Hz to 10 kHz, in particular in the range from 500 to 5000 Hz).

[0078] In the system shown in Fig. 2, the control signal can specify which 10A BLDC motor is to be addressed, for example, by the number or duration of the input control signal. Optionally, only those 10A BLDC motors that need to be adjusted to reach the maintenance position are automatically controlled in maintenance mode.

[0079] Fig. 5 shows a possible structure of a message 4, which the control unit 11A, 11B can be configured to receive from the respective communication node 30. The message 4 has a predefined length in bits. The message 4 comprises a header 40 and a data portion 41. The header contains control information, e.g., identifying a recipient of the message. Furthermore, the aforementioned clock signal 400 of the communication node 30 can be inserted into at least some messages. Thus, a relatively simply constructed clock generator can be provided in the control unit 11A, 11B, which does not need to have a particularly high level of accuracy because its clock can be corrected by the received clock signal 400. This simplifies production, allows the use of simpler components, and reduces production costs. For example, communication via the interface 110 takes place based on the received clock signal 400.This allows the timing of the communication to be adapted to the clock signal 400.

[0080] The data part 41 contains at least one control command 410 with which the control unit 11A, 11B then controls the respective BLDC motor 10A, 10B.

[0081] Fig. 6 shows a method for controlling a drive device 1A, 1B with a brushless DC motor, BLDC motor 10A, 10B, and a control unit 11A, 11B, the method comprising the following steps performed by the control unit 11A, 11B:

[0082] Step S1: Receiving, in a normal operating mode of the control unit 11A, 11B and by communicating with a communication node 30, 11B via an interface 110 of the control unit 11A, 11B, control commands 410 and controlling the BLDC motor 10A, 10B based on the received control commands 410.

[0083] Step S2: Detecting a communication disruption with the communication node 30, 11B via the interface 11A, 11B and / or a predefined input and switching to a maintenance mode in response to the detected disruption and / or the predefined input. If a communication disruption with the communication node 30, 11B via the interface 11A, 11B and / or a predefined input is detected (Fig. 6, branch "Y"), the method continues with step S3. Otherwise (Fig. 6, branch "N"), the method returns to step S1.

[0084] Step S3: Controlling, in maintenance mode, the BLDC motor (10A, 10B) independently of communication with the communication node (30, 11B).

[0085] Fig. 7 shows an exemplary embodiment of the BLDC motor 10A. This is designed as an internal rotor. A rotor 102A of the BLDC motor 10A is arranged within a stator 101A so as to be rotatable thereto. On the stator 101A, several coils are connected to three phases U, V, W (a different number of phases can also be provided) of a three-phase alternating voltage. The coils are connected to a common star point P. Applying the alternating voltage causes a current to flow and thus a rotation of the rotor 103A, to which permanent magnets 103A are attached. By way of example, one coil is provided for each phase II, V, W, but a larger number can also be provided.

[0086] In Fig. 7, an inverter 100 is also illustrated as an example, which converts a direct voltage into the three-phase alternating voltage with the phases II, V, W.

[0087] Fig. 8 shows an exemplary embodiment of the BLDC motor 10B. This is designed as an external rotor. A rotor 102B of the BLDC motor 10B is arranged within a stator 101B so as to be rotatable therewith. On the stator 101B, several coils are connected to three phases II, V, W (a different number of phases can also be provided here) of a three-phase alternating voltage. The coils are connected to a common star point P. Applying the alternating voltage causes a current to flow and thus a rotation of the rotor 103B, to which permanent magnets 103B are attached. By way of example, three coils are provided for each phase II, V, W, but a smaller or larger number can also be provided.

[0088] List of reference symbols

[0089] 1A, 1B drive device

[0090] 10A, 10B brushless DC motor (BLDC motor) 100 inverter

[0091] 101A, 101B Stator 102A, 102B Rotor 103A, 103B Permanent magnet 11A, 11B Control unit, seat control unit 110 Interface

[0092] 111 Storage medium

[0093] 112 Processor arrangement

[0094] 113A-113D Pin

[0095] 113 clock generator

[0096] 114 housings

[0097] 115 Cover

[0098] 116 radio interface

[0099] 117 socket

[0100] 118 Predetermined breaking point

[0101] 119 Motor connection

[0102] 12 Angle sensor

[0103] 2 vehicle seats

[0104] 20 Seat part

[0105] 21 Backrest

[0106] 22 Backrest tilt adjustment device

[0107] 220 Fitting arrangement

[0108] 23 Seat height adjustment device

[0109] 230 swivel arm

[0110] 24 Longitudinal adjustment device

[0111] 240 seat rail

[0112] 241 floor rail

[0113] 242 stop

[0114] 3 Bus system

[0115] 30 communication nodes

[0116] 300 clocks

[0117] 31 plugs

[0118] 32 Cable 4 Message

[0119] 40 headers

[0120] 400 clock signal

[0121] 41 Data part 410 Control command

[0122] A Power supply connection

[0123] FB vehicle floor

[0124] P star point

[0125] S Swivel axis U, V, W Phase

[0126] X Vehicle longitudinal direction

[0127] Z Vehicle height direction

Claims

Claims 1. Drive device (1A, 1B), in particular for a vehicle seat (2), with a brushless DC motor, BLDC motor (10A, 10B), and a control unit (11A, 11B), wherein the control unit (11A, 11B) is configured to: receive control commands (410) in a normal operating mode of the control unit (11A, 11B) by communicating with a communication node (30, 11B) via an interface (110) of the control unit (11A, 11B) and to control the BLDC motor (10A, 10B) based on the received control commands (410); detect a disruption in communication with the communication node (30, 11B) via the interface (110) and / or a predefined input and switch to a maintenance mode in response to the detected disruption and / or the predefined input; and in maintenance mode, to control the BLDC motor (10A, 10B) independently of communication with the communication node (30, 11B).

2. Drive device (1A, 1B) according to claim 1, characterized in that the interface (110) is set up for communication via a bus system (3).

3. Drive device (1A, 1B) according to claim 2, characterized in that the bus system (3) is a LIN bus or a CAN bus.

4. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to detect a timeout and / or an inadmissible level through communication via the interface (110).

5. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to recognize an interruption of communication as the disruption of communication via the interface (110).

6. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to receive messages (4) each having a header (40) and a data part (41) through communication via the interface (110) and to read out a respective control command (410) from a respective data part (41).

7. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is further configured to detect at least one control signal and to control the BLDC motor (10A, 10B) in the maintenance mode based on the at least one detected control signal.

8. Drive device (1A, 1B) according to claim 7, characterized in that the predefined input indicates the at least one control signal.

9. Drive device (1A, 1B) according to claim 7 or 8, characterized in that the control unit (11A, 11B) is configured to control the BLDC motor (10A, 10B) in the maintenance mode based on the at least one control signal such that the BLDC motor (10A, 10B) performs a predefined number of revolutions and / or effects an adjustment to a predetermined position, in particular up to a stop (242).

10. Drive device (1A, 1B) according to one of claims 7 to 9, characterized in that the control unit (11A, 11B) is configured to receive the at least one control signal in a way other than through communication with the communication node (30, 11B).

11. Drive device (1A, 1B) according to one of claims 7 to 10, characterized in that the control unit (11A, 11B) is configured to receive the at least one control signal wirelessly.

12. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to receive the predefined input as a potential applied to at least one pin (113A) of the control unit (11A, 11B), as a current flow via at least one pin (113A) and / or as an electrical connection between two pins (113B, 113C) of the control unit (11A, 11B).

13. Drive device (1A, 1B) according to claim 12, characterized in that the pin(s) (113A-113C) is / are covered by a plug (31) connected to the interface (110) and / or a housing (114) and / or a breakable cover (115).

14. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to detect the predefined input as an undershoot or overshoot of a predetermined voltage.

15. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to detect the predefined input based on a predetermined duration and / or a predetermined sequence, in particular in the form of a Morse code.

16. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to reduce a rotational speed of the BLDC motor (10A, 10B) in the maintenance mode compared to the normal operating mode.

17. Drive device (1A, 1B) according to one of the preceding claims, characterized in that the control unit (11A, 11B) is configured to activate the BLDC motor (10A, 10B) intermittently and / or with an imposed frequency in the audible range in maintenance mode.

18. Drive device (1A, 1B) according to one of the preceding claims, characterized in that in the maintenance mode a direction of rotation of the BLDC motor (10A, 10B) is fixed, can be changed by detecting a newly present predefined input or can be set by information in the predefined input.

19. Drive device (1A) according to one of the preceding claims, characterized by a plurality of BLDC motors (10A, 10B) controllable by the control unit (11B).

20. Vehicle seat (2), characterized by at least one drive device (1A, 1B) according to one of the preceding claims, wherein the drive device (1A, 1B) is designed to adjust at least one adjusting device (22, 23, 24) of the vehicle seat (2).

21. Vehicle seat (2) according to claim 20, characterized in that the at least one adjusting device (22, 23, 24) comprises a backrest inclination adjusting device (22) for adjusting an inclination of a backrest (21) of the vehicle seat (2), a seat height adjusting device (23) for adjusting a seat height of a seat part (20) of the vehicle seat (1A, 1B) or a longitudinal adjusting device (24) for adjusting a longitudinal position of at least the seat part (20).

22. A method for controlling a drive device (1A, 1B) with a brushless DC motor, BLDC motor (10A, 10B), and a control unit (11A, 11B), the method comprising the following steps performed by the control unit (11A, 11B): Receiving (S1), in a normal operating mode of the control unit (11 A, 11 B) and by communicating with a communication node (30, 11 B) via an interface (110) of the control unit (11 A, 11 B), control commands (410) and controlling the BLDC motor (10A, 10B) based on the received control commands (410); Detecting (S2) a disruption of communication with the communication node (30, 11 B) via the interface (110) and / or a predefined input and Switching to a maintenance mode in response to the detected fault and / or the predefined input; and Controlling (S3), in maintenance mode, the BLDC motor (10A, 10B) independently of communication with the communication node (30, 11B).

23. Computer-readable storage medium (111) on which instructions are stored which, when executed by a control unit (11A, 11B) of a drive device (1A, 1B) with a brushless DC motor, BLDC motor (10A, 10B), cause the control unit (11A, 11B) to carry out the method according to claim 22.

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