CONTROL DEVICE AND METHOD FOR NOISE REDUCTION OF AUXILIARY ASSEMBLIES FOR A VEHICLE

Abstract

The invention relates to a control device (1) and to a control method for noise reduction for a vehicle. The control device comprises the following: at least one supported auxiliary assembly for the vehicle, for example an air conditioning system (4) having an air conditioning compressor (40), an electrical accumulator (60) or a range extender (70), wherein the auxiliary assembly emits vibrations in operation; at least one vibration sensor (21a) for detecting vibrations; at least one controllable vibration actuator (22a) for generating vibrations and a control unit (10), which is connected to the vibration sensor and the vibration actuator or the vibration damper, wherein the control unit (10) is designed, based upon the detected vibrations, to generate control signals for transmission to the vibration actuator or the vibration damper (45, 52, 71, 81), which result in the vibrations emitted by the auxiliary assembly being reduced and/or masked in a vehicle interior (3).

Claims

1. A control device for noise reduction for a vehicle selected from a group consisting of an electric vehicle and a hybrid vehicle, comprising: at least one mounted auxiliary assembly for the vehicle, wherein the auxiliary assembly emits vibrations during operation; at least one vibration sensor configured to detect vibrations; at least one control unit configured to generate control signals based on the detected vibrations; and at least one controllable vibration actuator configured to generate vibrations based on the control signals and/or at least one controllable semi-active vibration damper of the mounting of the auxiliary assembly configured to damp vibrations based on the control signals to reduce and/or mask vibrations emitted by the auxiliary assembly in an interior of the vehicle and/or in a surroundings of the vehicle.

2. The control device according to claim 1, wherein the a vibration sensor is an interior microphone arranged on a headrest of a vehicle seat for detecting sound in the interior of the vehicle or is an exterior microphone for detecting ambient noises.

3. The control device according to claim 2, wherein the vibration actuator is an interior speaker oriented at the interior of the vehicle, or is an exterior speaker oriented at the surroundings of the vehicle, and wherein the vibration actuator emits anti-sound and/or masks sound.

4. The control device according to claim 1, wherein: the auxiliary assembly comprises a scroll compressor or a range extender; the auxiliary assembly is associated with a rotational speed sensor; and the control unit is configured to, based on a rotational speed of the scroll compressor or of the range extender detected by the rotational speed sensor, generate control signals to variably adjust the spring stiffness and/or damping of the semi-active vibration damper.

5. The control device according to claim 1, wherein the semi-active vibration damper comprises a magnetorheological or an electrorheological material comprising a fluid, a gel, an elastomer, or a foam.

6. The control device according to claim 1, wherein the vibration actuator is an active pulsation damper arranged in a coolant line of an air conditioning system.

7. The control device according to claim 1, wherein the vibration actuator is a single-axis or multi-axis shaker for arrangement on at least one selected from a group consisting of a roof, a floor panel, and a steering column of the vehicle.

8. The control device according to claim 1, wherein the vibration sensor is an acceleration sensor for arrangement on a vehicle chassis.

9. The control device according to claim 1, wherein the control device comprises: a GPS receiver; and a transmission/receiving unit configured to receive noise emission and/or noise immission limit value data based on a position and/or a time received by the GPS receiver.

10. The control device according to claim 1, wherein the control device comprises a computer-readable on-board data memory with ambient acoustic data of the vehicle and/or noise emission and/or noise immission limit value data related to the surroundings of the vehicle.

11. An electric vehicle or hybrid vehicle comprising the control device according to claim 1.

12. A control method for noise reduction for a vehicle, comprising: detecting vibrations emitted by an auxiliary assembly of the vehicle using at least one vibration sensor; generating control signals using a control unit (10) based at least on the detected vibrations; transmitting the control signals to at least one controllable vibration actuator and/or at least one controllable semi-active vibration damper of the mounting of the auxiliary assembly; and generating vibrations using the vibration actuator and/or damping vibrations using the vibration damper, based on the transmitted control signals, in order to reduce and/or mask the vibrations emitted by the auxiliary assembly in an interior of the vehicle and/or in a surroundings of the vehicle.

13. The control method according to claim 12, wherein the control method is carried out when the vehicle is stopped during operation of the auxiliary assembly.

14. The control method according to claim 12, further comprising: detecting a rotational speed of a scroll compressor in the auxiliary assembly and associated with an air conditioning system or a range extender in the auxiliary assembly; and generating, based on the detected rotational speed, control signals for variably adjusting the spring stiffness and/or damping of the semi-active vibration damper of the mounting of the auxiliary assembly.

15. The control method according to claim 12, further comprising: detecting ambient noise of the vehicle using of an exterior microphone; and storing the detected ambient noise in a computer-readable on-board data memory in the form of recorded reference acoustic signals.

16. The control method according to claims 12, further comprising: receiving noise emission and/or noise immission limit value data from a charging station for the vehicle or based on received GPS data, wherein the noise emission and/or noise immission limit value data relate to the surroundings of the vehicle.

17. The control method according to claim 12, further comprising: variably detecting particularly variably, the charging power of the electric accumulator of the vehicle during the charging process based on the cooling output of an air conditioning system necessary for cooling the electric accumulator during the charging process, while maintaining noise emission and/or noise immission limit values.

18. The control method according to claim 12, further comprising: emitting sound in the surroundings of the vehicle using at least one exterior speaker for masking the sound emitted by an auxiliary assembly, wherein the sound is based on recorded reference acoustic signals read-out in chronologically irregular intervals.

19. The control method according to claim 12, further comprising: prioritizing the generation of the control signals based on a seat occupation of the vehicle, detected using sensors, and/or detected surroundings data of the vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Exemplary embodiments of the invention are subsequently described by way of the drawings.

[0047] FIG. 1 shows a schematic depiction of a vehicle with a control device according to one or more embodiments of the invention; and

[0048] FIG. 2 shows a schematic depiction of a control device according to one or more embodiments of the invention.

DETAILED DESCRIPTION

[0049] In the subsequent description of one or more embodiments of the invention, the same reference numerals are used for identical and identically acting elements.

[0050] FIG. 1 shows a vehicle 100 according to one or more embodiments of the invention, in this case an electric or hybrid vehicle, having a control device 1 according to one or more embodiments of the invention, wherein vehicle 100 has different auxiliary assemblies, like an air conditioning system 4, power steering 50, and an electric accumulator 60. Electric accumulator 60 functions for the power supply for the drivetrain and/or other auxiliary assemblies of vehicle 100. Additionally, a range extender 70 is optionally provided, which is designed in this case as an auxiliary assembly with an internal combustion engine, to which a generator 80 is coupled. Air conditioning system comprises an air conditioning compressor 40, in particular a scroll compressor, an evaporator 41, a condenser 42, a fan 43, and expansion valve 43, and connecting coolant lines. Air conditioning system 4 may be used for heating or cooling of vehicle interior 3, and for cooling electric accumulator 60, in particular during charging. Air conditioning compress 40 is mounted via semi-active vibration damper 45 of mounting 401 on a subframe 46, which is, e.g., approximately double the length and width of air conditioning compressor 40. Likewise, range extender 70 and generator 80 are mounted via semi-active vibration damper 71 of mounting 701 on the vehicle chassis. A mutual mounting with additional components of air conditioning system 4, e.g., evaporator 41 and condenser 42, or individual mountings may respectively be provided. This likewise applies for range extender 70 and generator 80, and potential additional elements peripheral to the drive. Power steering 50 provided in the area of steering column 53 comprises a servo pump 50. Auxiliary assemblies, like air conditioning system 4 with air conditioning compressor 40, power steering 50 with servo pump 52, electric accumulator 60, range extender 70, and generator 80 generate vibrations during operation, which may cause vibro-acoustic effects, which may be perceived as disturbing by occupants of vehicle 100 in vehicle interior 3, or by persons in vehicle surroundings 2, thus outside of vehicle 100.

[0051] According to one or more embodiments of the invention, control device 1 depicted in FIGS. 1 and 2 comprises, in addition to the listed auxiliary assemblies, a control unit 10, which has at least one processing unit in particular a CPU, and vibration sensors 21a, 21b, 32, 20, 30, 31, 52 and controllable vibration actuators 22a, 22b, 33, 34, 35, 36, 51, 47a, 47b, and listed controllable, semi-active vibration dampers 45, 71, which are all connected to each other communicatively or in a signal-conducting manner via vehicle data bus 5 (see FIG. 2). In addition, control devices (not depicted) are provided, assigned to the vibration sensors and to the vibration actuators. In addition, control device 1 comprises an on-board vehicle memory 6, a transmission/receiving unit 91, and a GPS receiver 92, which are all connected to control unit 10 via vehicle data bus 5. Control unit 10 executes a control algorithm, stored on a computer-readable memory, whose input parameters are based on sensor signals generated by vibration sensors 21a, 21b, 32, 20, 30, 31, 52 and whose output parameters are transmitted as control signals to vibration actuators 22a, 22b, 33, 34, 35, 36, 51, 47a, 47b and/or semi-active vibration dampers 45, 71. However, only some of the listed vibration sensors, vibration actuators or vibration dampers and subgroups of the same may also be provided in control device 1. In particular, embodiments of the invention are included, which have only some of the listed auxiliary assemblies, in particular only air conditioning system 4, power steering 50, electric accumulator 60 or range extender 70, and any combination thereof.

[0052] According to one aspect of one or more embodiments of the invention, vibration sensors are arranged as first and second interior microphones 21a or 21b on headrests 9a or 9b of vehicle seats 8a or 8b, which detect sound in vehicle interior 3 and transmit corresponding sensor signals to control unit 10. In addition, vibration actuators are aligned with the vehicle interior as interior speaker 22a and/or hifi interior speaker 22b, which emit sound into the vehicle interior, based on control signals generated by the control unit, in order to generate a sound field within the vehicle interior with, at least locally, destructive interference. By feeding the sensor signals detected by interior microphones 21a and 21b back to the control unit, interior speakers 22a and/or 22b may be controlled so that sound is cancelled out or at least minimized in a targeted way in the area of headrests 9a and 9b. In particular a targeted wave field synthesis may be created in vehicle interior 3 via multiple interior speakers. Masking sound may also be emitted via interior speakers 22a, 22b in order to cover vibrations emitted by an auxiliary assembly.

[0053] According to another aspect of one or more embodiments of the invention, a vibration sensor is provided as an exterior microphone 32 and a vibration actuator as an exterior speaker 33 oriented at vehicle surroundings 2. Multiple exterior microphones 32 and/or exterior speakers 33 may be provided at different points of the vehicle or at different orientations. Surroundings noises, for example, of vehicle 100 may be detected via exterior microphone 32 and stored in an on-board data memory 6, preferably after a data processing step. Similar to how this was described in conjunction with the vehicle interior, destructive interference may be also generated in the sound field in the vehicle surroundings via exterior speaker 33, in particular by emitting anti-sound. Alternatively or additionally, noises from auxiliary assemblies may be masked, for example, by playing back surroundings noise previously recorded as reference acoustic signals and stored in on-board data memory 6, like traffic noise, construction noise, wind noises, rain noises, birdsong and other noises that occur in the vicinity of the vehicle.

[0054] According to another aspect of one or more embodiments of the invention, vibration sensors are provided as a structure-borne sound sensitive acceleration sensor 20 assigned to the vehicle interior and additional acceleration sensors 30, 31 in the front area of the vehicle and an acceleration sensor 52 assigned to steering column 53, in order to detect vibrations in the form of structure-borne sound and to transmit or feed corresponding sensor signals back to control unit 10. Electrodynamic vibration actuators in the form on single-axis or multi- axis shakers, namely a shaker 36 applied on the roof, a shaker 35 applied on the floor panel, a shaker 34 applied in the front area of vehicle 100, and a shaker 51 arranged on steering column 53, generate, based on control signals generated by control unit 10, active mechanical vibrations for damping or cancelling out vibrations generated by an auxiliary assembly, for example, by air conditioning compressor 40 or servo pump 54. In this way, undesirable, perceptible vibrations and audible vibro-acoustic effects may be prevented or at least reduced.

[0055] According to another aspect of one or more embodiments of the invention, air conditioning compressor 40 and/or range extender 70 are equipped with a rotational speed sensor 48 or 72. By detecting the rotational speed of an auxiliary assembly, the spring stiffness characteristic and/or damping characteristic of the mounting of this auxiliary assembly may be adjusted or controlled depending on the rotational speed via semi-active vibration dampers, so that the auxiliary assembly is decoupled as well as possible from the vehicle chassis, on which it is mounted, in particular for different operating states of the auxiliary assembly. The semi-active vibration dampers comprise, for example, magnetorheological or electrorheological materials, whose spring stiffness characteristics and damping characteristics are magnetically or electrically controllable. Alternatively or additionally, active pulsation dampers 47a, and 47b are provided in coolant lines of air conditioning system 4, and which may be arranged in this case in the supply line or drain line of air conditioning compressor 40, and may damp flow-dynamically generated vibrations based on control signals transmitted by control unit 10.

[0056] Control device 1 may receive noise emission and/or noise immission limit value data via transmission/receiving unit 91, which data are queried by control device 1 from an external database, for example, based on a position signal and/or time signal received from a GPS receiver 92 for vehicle 100 via a radio connection. In particular, noise emission and/or noise immission limit value data may be transmitted by a charging station for electric accumulator 60 to control device 1 via transmission/receiving unit 91. The limit values contained in the noise emission and/or noise immission limit value data are taken into consideration by control unit 10 during control steps, insofar as these noise limit values are maintained, for example, in vehicle interior 3 and/or in vehicle surroundings 2. The rotational speed and/or load of air conditioning compressor 40 or of range extender 70 is preferably controlled based on the prespecified noise emission and/or noise immission limit values.

[0057] The control method according to the invention is preferably carried out when vehicle 100 is stopped, yet an auxiliary assembly is operated, in particular when air conditioning system 4 is operated. A few examples for applications of the control method are subsequently described.

[0058] For example, in a fully occupied vehicle in summer waiting at a red light, the cooling requirements for vehicle interior 3 are high, so that air conditioning system 4 operates air conditioning compressor 40 with a high rotational speed. To minimize vibrations and humming noises in vehicle interior 3, the spring stiffness and damping of mounting 401 is adjusted by control unit 10 depending on the rotational speed via suitable control of semi-active vibration damper 45. Based on noises detected by interior microphones 21a and 21b, the characteristics of the mounting may be readjusted to further reduce the effects of the vibro-acoustic effects.

[0059] For example, in a vehicle, which is parked in summer on an unshaded parking lot while the driver would like to sleep with air conditioning system 4 switched on, a low blower level of interior fan 90 is set and air conditioning compressor 40 is operated at high rotational speed in order to provide sufficient cooling. Described control device 1 or the control method according to the invention provides a sufficiently quiet vehicle interior 3. In this case, a seat position, detected by sensors, in particular a lying position of vehicle seat 8a, 8b, may additionally be taken into consideration by the control system in order to locally achieve a more targeted control result. The seat position may be detected, for example, by at least one camera oriented at vehicle seat 8a, 8b, preferably at headrest 9a, 9b, or angle sensors for detecting the position of the backrest.

[0060] According to the control method according to one or more embodiments of the invention, a prioritization of control goals may be carried out, which target either vehicle interior 3 or vehicle surroundings 2. For example, in one scenario, electric accumulator 60 of an electric or hybrid vehicle 100 is charged via charging terminal 61 during a short driving interruption for further travel at a fast charging station, which is located, for example, in the vicinity of a street caf. Based on the high cooling requirements of electric accumulator 60 and the power electronics during the charging process, a high rotational speed of air conditioning compressor 40 is necessary. The seat occupation, in particular, of vehicle 100 may be detected by sensor. In the case that the vehicle is empty, for example, because the driver of the vehicle waits in the street caf during the charging process, a control goal intended for vehicle surroundings 2 may be prioritized instead of a control goal in favor of vehicle interior 3. Due to a very softly adjusted mounting 401 of air conditioning compressor 40, i.e., a low spring stiffness of semi-active vibration damper 45, a humming noise may be generated in vehicle interior 3 on the one hand, and high-frequency vibrations of air conditioning system 4 may be emitted into vehicle surroundings 2 on the other hand. If the vehicle is empty, by prioritizing the control goal by control unit 10, the humming noise is accepted in vehicle interior 3 in order to achieve a noise reduction in vehicle surroundings 2. Simultaneously, low-frequency vibrations based on exterior noise detected by exterior microphone 32 may be emitted into vehicle surroundings 2 via a tuned control of semi-active vibration damper 45 and/or active pulsation damper 47a, 47b.

[0061] Additionally advantageous embodiments arise by way of the subclaims. Reference is made at this point to the fact that all aspects of the invention mentioned above are claimed as essentially for the invention when considered alone and in any combination, in particular the details depicted in the drawings. The same applies for the method steps described in greater detail. Alterations form this are familiar to the person skilled in the art.

[0062] It is to be appreciated that the Detailed Description section, and not the Summary and Abstract sections, is intended to be used to interpret the claims. The Summary and Abstract sections may set forth one or more but not all exemplary embodiments of the present invention as contemplated by the inventor(s), and thus, are not intended to limit the present invention and the appended claims in any way.

[0063] The present invention has been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.

[0064] The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present invention. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.

LIST OF REFERENCE NUMERALS

[0065] 1 Control device [0066] 2 Vehicle surroundings [0067] 3 Vehicle interior [0068] 4 Air conditioning system [0069] 5 Vehicle data bus [0070] 6 Vehicle data memory [0071] 8a Vehicle seat [0072] 8b Vehicle seat [0073] 9a Headrest [0074] 9b Headrest [0075] 10 Control unit [0076] 20 Acceleration sensor [0077] 21a First interior microphone [0078] 21b Second interior microphone [0079] 22a Interior speaker [0080] 22b Hifi interior speaker [0081] 30 Acceleration sensor [0082] 31 Acceleration sensor [0083] 32 Exterior microphone [0084] 33 Exterior speaker [0085] 34 Shaker [0086] 35 Shaker [0087] 36 Shaker [0088] 40 Air conditioning compressor [0089] 41 Evaporator [0090] 42 Condenser [0091] 43 Fan [0092] 44 Expansion valve [0093] 45 Vibration damper [0094] 46 Subframe [0095] 47a Active pulsation damper [0096] 47b Active pulsation damper [0097] 48 Rotational speed sensor [0098] 401 Mounting [0099] 50 Power steering [0100] 51 Shaker on the steering column [0101] 52 Acceleration sensor [0102] 53 Steering column [0103] 54 Servo pump [0104] 60 Electric accumulator [0105] 61 Charging terminal [0106] 70 Range extender [0107] 71 Vibration damper [0108] 72 Rotational speed sensor [0109] 701 Mounting [0110] 80 Generator [0111] 90 Interior fan [0112] 91 Transmission/receiving unit [0113] 92 GPS receiver [0114] 100 Vehicle