System capable of actively inhibiting wind vibration noise of automobile window and automobile

Abstract

The invention discloses a system capable of actively inhibiting wind vibration noise of an automobile window and an automobile. The system comprises automobile window glass and an automobile window sunshade curtain system capable of adjusting the mesh diameter and porosity parameters of sunshade curtain cloth in real time based on the opening value of the automobile window. Determining an opening value of the window glass of the vehicle based on the actual position of the window glass of the vehicle and the calibrated position of the window glass of the vehicle; based on the opening value of the vehicle window glass, the mesh diameter and porosity parameters of the vehicle window sunshade curtain system are obtained; the vehicle window sunshade curtain system completes adjustment of vehicle window sunshade curtain cloth based on the mesh diameter and porosity parameters. According to the method, the mesh diameter and porosity of the sunshade curtain cloth can be adjusted in real time, the flow field characteristics under each window opening degree can be matched in real time, and finally a good window wind vibration noise improvement effect is obtained.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and more particularly to a system and a vehicle capable of actively suppressing wind buffeting noise of automobile windows. Background Art

[0002] Wind buffeting noise when the car's windows are opened has always been an important issue that affects the user's driving comfort. This low-frequency, high-sound-pressure noise not only causes discomfort to the passengers, but long-term exposure to this environment may also bring health risks and ultimately endanger driving safety. In actual driving, opening the car window is an inevitable daily operation, so how to effectively suppress wind buffeting noise has become a technical problem that needs to be solved in the process of automobile development.

[0003] At present, the industry has proposed three main solutions to the problem of wind vibration of car windows. The first technical solution is to install a deflector on the surface of the car body. However, due to the requirements of the whole vehicle styling, the size of the deflector is difficult to meet the aerodynamic optimization requirements, which not only affects the appearance of the car body, but also fails to achieve the ideal noise reduction effect. The second technical solution is to arrange a spoiler net at the position of the car window glass. However, due to the fixed characteristic opening size of the spoiler net, its flow resistance model cannot be dynamically adjusted with the flow field characteristics under different window opening degrees, so it is difficult to achieve wind vibration suppression under all working conditions. The third technical solution is to optimize the wind vibration performance by adjusting the window opening combination and the opening degree. Although this solution can improve the wind vibration problem in some cases, it not only limits the user's freedom to open the window, which violates the original design intention of convenience of use, but also cannot effectively solve the wind vibration problem when the rear window is fully opened.

[0004] In summary, it is urgent to develop a solution to the wind buffeting problem caused by opening the windows when the car is driving. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a sunshade control system in response to the defects in the prior art, which can adjust the mesh diameter and porosity of the sunshade curtain in real time, match the flow field characteristics under various window openings in real time, and ultimately achieve better improvement effect on window wind vibration noise.

[0006] The technical solution adopted by the present invention to solve its technical problem is: the present invention provides a system that can actively suppress wind vibration noise of automobile windows, including window glass and a window sunshade system that can adjust the mesh diameter and porosity parameters of the window sunshade cloth in real time based on the window opening value, the opening value of the vehicle window glass is determined based on the actual position of the vehicle window glass and the calibrated position of the vehicle window glass; the mesh diameter and porosity parameters of the window sunshade system are obtained based on the opening value of the window glass; the window sunshade system completes the adjustment of the window sunshade cloth based on the mesh diameter and porosity parameters.

[0007] In a preferred embodiment of the present invention, a vehicle window sunshade system includes a vehicle window sunshade fabric unit and an adjustment unit, wherein the vehicle window sunshade fabric unit includes transverse fibers and longitudinal fibers, and the adjustment unit includes a transverse adjustment component and a longitudinal adjustment component, wherein the transverse adjustment component is used to adjust the transverse spacing between two adjacent transverse fibers of the fabric, and the longitudinal adjustment component is used to adjust the longitudinal spacing between two adjacent longitudinal fibers of the fabric.

[0008] In a preferred embodiment of the present invention, a method for obtaining mesh diameter and porosity parameters of a vehicle window sunshade system based on the opening value of a vehicle window glass comprises: establishing a wind vibration operating condition table according to the window opening range; calibrating a vehicle window wind vibration simulation model using wind tunnel measurement data of wind vibration noise of actual vehicle windows; setting a porous medium flow resistance model in the vehicle window sunshade area, wherein the porous medium flow resistance model comprises a viscous drag coefficient and an inertial drag coefficient; determining a value range of the viscous drag coefficient and the inertial drag coefficient based on the material and specification of the vehicle window sunshade fabric, and obtaining a sample set thereof; determining the optimal viscous drag coefficient and the inertial drag coefficient of each vehicle window at different openings through wind vibration noise simulation optimization; converting the optimal viscous drag coefficient and the inertial drag coefficient into corresponding mesh diameter and porosity parameters; and writing the mesh diameter and porosity parameters into the control program of the controller.

[0009] In a preferred embodiment of the present invention, the wind vibration operating condition table includes window openings ranging from 5% to 100%, divided into intervals of 5%, and determines the position of the window glass at each opening.

[0010] In a preferred embodiment of the present invention, the start-up conditions and the shut-down conditions of the window sunshade control system are set; wherein the start-up conditions include the vehicle speed and the window opening, and the shut-down conditions include the window closing command and the vehicle locking command.

[0011] In a preferred embodiment of the present invention, sunshade curtain fabric products are selected based on the mesh diameter and porosity parameters of each window at 100% opening; the curtain fabric mesh diameter and porosity parameters of each window at each opening are verified and optimized through actual vehicle wind vibration noise wind tunnel tests; and the optimized parameters are updated to the control program of the controller.

[0012] In a preferred embodiment of the present invention, the viscous resistance coefficient and the inertial resistance coefficient are determined by the pressure drop of the porous medium material, the material thickness and the surface flow velocity.

[0013] In a preferred embodiment of the present invention, the mesh diameter and porosity parameters are determined based on the pressure drop, thickness, surface flow velocity, air density and air viscosity of the porous medium material.

[0014] In a preferred embodiment of the present invention, the control system continuously detects the closing condition of the vehicle window sunshade system.

[0015] The invention also discloses a vehicle, which comprises a system capable of actively suppressing wind vibration noise of a vehicle window.

[0016] The beneficial effects of the present invention are as follows: compared with the wind vibration noise control method in the prior art, the present invention does not need to change the vehicle body structure, does not affect the appearance of the vehicle, and avoids interfering with the user's window opening habits, providing an innovative solution that takes into account both noise reduction effect and ease of use. The technical solution of the present invention can not only effectively improve the noise environment in the vehicle and enhance driving comfort, but also has good engineering application value.

[0017] Firstly, the present invention establishes a complete wind vibration condition table and calibrates the simulation model in combination with wind tunnel test data, thus ensuring the accuracy and reliability of wind vibration noise simulation analysis. Secondly, the present invention applies the porous medium flow resistance model to the design of window sunshade curtains, and realizes precise control of wind vibration noise by optimizing the resistance coefficients of viscosity and inertia.

[0018] Furthermore, the present invention adopts a parametric design method, by establishing the correspondence between mesh diameter and porosity and flow resistance coefficient, so that the theoretical optimization results can directly guide the actual selection and manufacturing of sunshade curtain fabrics, significantly improving the design efficiency. At the same time, the present invention takes into account the wind vibration characteristics in the full range of working conditions, and can achieve effective wind vibration noise suppression in the window opening range of 5% to 100%, greatly improving the applicability of the solution.

[0019] In terms of control strategy, the present invention realizes intelligent control of the window sunshade system by systematically setting the start and shut down conditions, including key parameters such as vehicle speed and window opening. This adaptive adjustment mechanism based on real-time working conditions not only ensures the noise reduction effect, but also improves the user experience. In addition, the present invention also establishes a complete technical route from simulation optimization to actual vehicle verification, and corrects and iterates the optimization parameters through actual vehicle wind tunnel tests, further improving the engineering practicality of the solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0021] Figure 1 It is a schematic diagram of a prior art vehicle window sunshade;

[0022] Figure 2 It is a schematic diagram of a vehicle window sunshade control system of the present invention;

[0023] Figure 3 It is a schematic diagram of a vehicle window sunshade control system of the present invention;

[0024] Figure 4 It is a schematic diagram of the improvement effect of a vehicle window sunshade control system of the present invention at various vehicle speeds when the rear window opening is 50%;

[0025] Figure 5 It is a schematic diagram of the improvement effect of a vehicle window sunshade control system of the present invention when the rear window opening is 50% and the vehicle speed is 70 km / h;

[0026] Figure 6 It is a working flow chart of a vehicle window sunshade control system of the present invention;

[0027] Figure 7 The invention discloses a design flow chart of a vehicle window sunshade control system. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] like Figure 2-7 As shown, the present invention discloses a vehicle window sunshade control system, which analyzes the solution to the vehicle window wind vibration based on the mechanism of the vehicle window wind vibration. Since the mesh diameter and porosity of the current vehicle window sunshade curtain cannot be changed, the solution cannot solve the wind vibration problem under various vehicle window openings. In view of the shortcomings of the vehicle window sunshade solution, this patent proposes a vehicle window sunshade structure with real-time adjustable mesh diameter and porosity of the sunshade curtain. By adjusting the mesh diameter and porosity of the sunshade curtain in real time, the flow field characteristics under various vehicle window openings are matched in real time, and finally a better improvement effect of vehicle window wind vibration noise is obtained. Specifically, the steps of the present invention include:

[0030] Step 1: The vehicle is started and the window sunshade system is activated.

[0031] Step 2: The control system detects the starting conditions of the window sunshade system. If the starting conditions are not met, the control system continues to detect the starting conditions; when the starting conditions are met, the voice prompts the occupants that "the window sunshade system will be opened."

[0032] Step 3: The system controls the motor to open the sunshade and cover the entire window glass area.

[0033] Step 4: The control system detects the actual position of the window glass, calculates its actual opening value and compares it with the opening setting value in the system, determines the opening value closest to it, and indexes the mesh diameter and porosity of the corresponding sunshade curtain fabric in the system.

[0034] Step 5: The controller sends instructions to the transverse and longitudinal control motors respectively. The motors pull the transverse and longitudinal fibers of the curtain fabric to move to the specified positions respectively, completing the real-time adjustment of the mesh diameter and porosity of the curtain fabric, and optimizing the wind vibration noise inside the car under the condition of the window opening in real time.

[0035] Step 6: When the control system detects that the window glass opening position has changed, the control system completes the wind vibration noise optimization under the new window opening according to steps 4-5.

[0036] Step 7: The control system detects the closing conditions of the window sunshade system. If the starting conditions are not met, the control system continues to detect the closing conditions; when the closing conditions are met, the voice prompts the occupants "the window sunshade system will be closed."

[0037] Step 8: The controller sends instructions to the transverse and longitudinal control motors respectively, and the motors pull the transverse fibers and longitudinal fibers of the curtain fabric to move to the initial positions respectively.

[0038] Step 9: The control system controls the motor to retract the window sunshade.

[0039] In step 4, the method for obtaining mesh diameter and porosity parameters of the vehicle window sunshade system based on the opening value of the vehicle window glass includes:

[0040] Step 4.1: Select commonly used window openings (5%-100%), with the window openings at intervals of 5%, and obtain a wind vibration condition table for each window opening; determine the position of the window glass at each opening based on the maximum sliding stroke of the window glass.

[0041] Table 1

[0042]

[0043] Step 4.2: Use the wind tunnel measurement data of the wind buffeting noise of the actual vehicle window of the existing model to calibrate the window wind buffeting simulation model.

[0044] Step 4.3: For the window sunshade area, assign a porous medium flow resistance model to the window sunshade fabric, as shown in the following formula (1).

[0045]

[0046] Where: ΔP is the pressure drop of the porous medium material, L is the thickness of the porous medium material, v ∞ is the flow velocity on the surface of the porous medium, a is the viscous resistance coefficient, and b is the inertial resistance coefficient.

[0047] Step 4.4: According to the common material specifications and parameter ranges of the window sunshade curtain, the value ranges of parameters a and b are obtained, and a sample set of the values ​​of the two parameters a and b is obtained by using a sampling method.

[0048] Step 4.5: Select a car window, select a car window opening in Table 1, use the method in step 4.2 to establish the corresponding car window wind vibration simulation model, substitute the value sample set of the two parameters a and b in step 4.4 into the simulation model in step 4.2 to perform wind vibration noise simulation optimization, and obtain the optimal solution of the two parameters a and b for the car window at this opening. opt 、b opt .

[0049] Step 4.6: Solve for a opt 、b opt Corresponding mesh diameter and porosity.

[0050] The Ergun empirical formula of the flow resistance model of porous media is shown in equation (2).

[0051]

[0052] Where: ΔP is the pressure drop of the porous medium material, L is the thickness of the porous medium material, v ∞ is the flow velocity on the porous medium surface, ε is the material porosity, d p is the particle diameter, ρ is the air density, and μ is the air viscosity.

[0053] By comparing equations (1) and (2), we can obtain the relationship between the two parameters a and b and the mesh diameter and porosity of the porous medium material, as shown in equations (3) and (4).

[0054]

[0055]

[0056] A opt 、b opt Substituting into equations (3) and (4) we can obtain the corresponding mesh diameter d: p and porosity ε.

[0057] Step 4.7: According to the method of steps 4.5-4.6, the mesh diameter d of the window at which the wind vibration noise in the car is optimal at all openings in Table 1 is obtained. p and porosity ε.

[0058] Step 4.8: According to the method of steps 4.5-4.7, solve the mesh diameter d when the wind vibration noise in the car is optimal at all openings of all windows in Table 1 p and porosity ε.

[0059] Step 4.9: Substitute the mesh diameter d of each window at each opening degree obtained in step 4.8 into p The porosity ε results are written into the control program of the controller.

[0060] Step 4.10: Determine the start-up conditions of the window sunshade control system, including vehicle speed, window opening, etc.; determine the closing conditions of the window sunshade control system, including window closing instructions, vehicle locking instructions, etc.

[0061] Step 4.11: Write the start and close conditions of the window sunshade control system in step 4.10 into the control program of the controller.

[0062] Step 4.12: Based on the parameter optimization results of step 4.8, index the mesh diameter d when the window opening is 100% p and porosity ε, and use them as initial values. Select the sunshade curtain products corresponding to the parameters, make car window sunshades and carry out wind tunnel tests on real vehicles to confirm the improvement effect of wind vibration noise in the car, and optimize the curtain mesh diameter d of each window at each opening. p and porosity ε.

[0063] Step 4.13: Optimize the mesh diameter d of each window at each opening of the actual vehicle p The porosity ε is updated to the control program of the controller to solidify the system control software.

[0064] The following takes the design and implementation of a rear window wind buffeting noise active suppression system of a certain vehicle model as an example to describe in detail the specific implementation process of the present invention.

[0065] S1, analyze the structural characteristics of the rear window glass of this model. The rear window glass of this model adopts electric lifting mode, and the maximum opening stroke is 450mm. According to the opening division principle in Table 1, 20 opening values ​​are determined at intervals of 5%, and the glass opening position corresponding to each opening value is accurately calculated using 3D modeling software. For example, the glass opening position P1 corresponding to 5% opening is 22.5mm, the position P2 corresponding to 10% opening is 45mm, and so on until the position P20 corresponding to 100% opening is 450mm.

[0066] S2, after completing the mapping relationship between the opening and the position, build a simulation model of the rear window wind vibration noise of the vehicle model. The model focuses on the external flow field characteristics of the vehicle body, the influence of the glass opening position on the airflow, and the acoustic characteristics of the cavity inside the vehicle. By setting different sunshade curtain parameters for iterative calculation, the optimal mesh diameter and porosity combination at each opening is optimized. For example, under the condition of 50% opening, the optimized mesh diameter is 0.8mm, and when the porosity is 65%, the wind vibration noise inside the vehicle is reduced most significantly.

[0067] S3, to verify the accuracy of the simulation optimization results, a wind tunnel test of wind vibration noise of a real vehicle was carried out. The test was carried out in an automotive acoustic wind tunnel test room with a wind speed range of 30-120km / h. A multi-channel acoustic test system was used to synchronously collect noise data from different measuring points in the vehicle. By comparing and analyzing the test results under different parameter combinations, the mesh diameter and porosity obtained by simulation optimization were fine-tuned and optimized. The final parameter results were written into the EEPROM of the controller for parameter indexing during actual system operation.

[0068] S4, the control strategy design of the system adopts a combination of real-time monitoring and intelligent adjustment. The control system continuously detects the start-up condition parameters including vehicle speed, window opening, ambient temperature, etc. When the vehicle speed exceeds 30km / h and the window opening is greater than 10%, the system determines that the start-up conditions are met. At this time, a voice prompt "the window sunshade system will be turned on" is issued through the in-car audio system to remind the occupants that the system is about to start.

[0069] S5, the start-up process is executed by a specially designed motor control mechanism. The mechanism adopts a dual-motor drive mode, and the output torque is not less than 2N·m, ensuring that the sunshade can be smoothly and quickly unfolded and cover the entire window glass area. During the unfolding process, a position feedback device is provided to monitor the position status of the sunshade in real time.

[0070] S6 uses a high-precision Hall sensor to detect the window glass position in real time with a resolution of 0.1mm. The controller converts the detected actual position into an opening value and compares it with the preset 20 standard openings, using the nearest neighbor principle to determine the opening value corresponding to the current working condition. Subsequently, the system reads the optimal mesh diameter and porosity parameters corresponding to the opening value from the EEPROM.

[0071] S7, the sunshade curtain fabric adopts an innovative variable structure design, which realizes dynamic adjustment of mesh characteristics through the relative displacement of transverse and longitudinal fibers. Two precision stepper motors control the movement of transverse and longitudinal fibers respectively, with a step accuracy of 0.01mm, ensuring the adjustment accuracy of mesh diameter and porosity. The system response time is less than 1 second, which can realize rapid adjustment when working conditions change.

[0072] S8, when the driver adjusts the window position, the system can respond to the change in time. The controller re-executes the parameter indexing and adjustment process to ensure that the best noise reduction effect is maintained under the new window opening conditions.

[0073] S9, the system's closing conditions include: detecting a window closing command, the vehicle speed dropping below 30 km / h, receiving a vehicle lock signal, etc. When any of the closing conditions is met, the system also informs the occupants through voice prompts that the closing operation is about to be performed.

[0074] S10, the closing process begins with the restoration of the curtain structure. The two motors run synchronously, driving the transverse and longitudinal fibers back to their initial positions, at which point the mesh diameter and porosity return to standard conditions.

[0075] S11, the system controls the unfolding motor to run in reverse, driving the sunshade to be retracted into the storage box. The entire storage process is smooth and reliable, and takes no more than 5 seconds. After the storage is completed, the control system enters the standby state, waiting for the next start condition to be triggered.

[0076] It should be noted that the automobile windows described in the present invention include but are not limited to automobile side windows and automobile roof windows.

[0077] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0078] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0079] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A system for actively suppressing wind vibration noise of automobile windows, characterized in that: The invention comprises a vehicle window glass and a vehicle window sunshade system which can adjust the mesh diameter and porosity parameters of the sunshade curtain fabric in real time based on the vehicle window opening value, wherein the vehicle window glass opening value is determined based on the actual position of the vehicle window glass and the calibrated position of the vehicle window glass; the mesh diameter and porosity parameters of the vehicle window sunshade system are obtained based on the opening value of the vehicle window glass; and the vehicle window sunshade system completes the adjustment of the vehicle window sunshade curtain fabric based on the mesh diameter and porosity parameters.

2. The system for actively suppressing wind buffeting noise of automobile windows according to claim 1, characterized in that: The vehicle window sunshade system includes a vehicle window sunshade curtain unit and an adjustment unit, wherein the vehicle window sunshade curtain unit includes transverse fibers and longitudinal fibers, and the adjustment unit includes a transverse adjustment component and a longitudinal adjustment component, wherein the transverse adjustment component is used to adjust the transverse spacing between two adjacent transverse fibers of the curtain, and the longitudinal adjustment component is used to adjust the longitudinal spacing between two adjacent longitudinal fibers of the curtain.

3. The system for actively suppressing wind buffeting noise of automobile windows according to claim 2, characterized in that: The method for obtaining mesh diameter and porosity parameters of a vehicle window sunshade system based on the opening value of a vehicle window glass comprises: establishing a wind vibration operating condition table according to the window opening range; calibrating a vehicle window wind vibration simulation model using wind tunnel measurement data of wind vibration noise of a real vehicle window; setting a porous medium flow resistance model in the vehicle window sunshade curtain area, wherein the porous medium flow resistance model includes a viscous drag coefficient and an inertial drag coefficient; determining the value range of the viscous drag coefficient and the inertial drag coefficient based on the material and specification of the vehicle window sunshade curtain, and obtaining a sample set thereof; determining the optimal viscous drag coefficient and the inertial drag coefficient of each vehicle window at different openings through wind vibration noise simulation optimization; converting the optimal viscous drag coefficient and the inertial drag coefficient into corresponding mesh diameter and porosity parameters; and writing the mesh diameter and porosity parameters into a control program of a controller.

4. The system for actively suppressing wind buffeting noise of automobile windows according to claim 3, characterized in that: The wind vibration working condition table includes window openings ranging from 5% to 100%, divided into intervals of 5%, and determines the position of the window glass at each opening.

5. The system for actively suppressing wind buffeting noise of automobile windows according to claim 3, characterized in that: The start-up conditions and the shut-down conditions of the window sunshade control system are set; wherein the start-up conditions include the vehicle speed and the window opening, and the shut-down conditions include the window closing command and the vehicle locking command.

6. The system for actively suppressing wind buffeting noise of automobile windows according to claim 3, characterized in that: The sunshade curtain fabric products are selected based on the mesh diameter and porosity parameters of each window when the opening degree is 100%; the curtain fabric mesh diameter and porosity parameters of each window at each opening degree are verified and optimized through wind tunnel tests on actual vehicles; and the optimized parameters are updated to the control program of the controller.

7. The system for actively suppressing wind buffeting noise of automobile windows according to claim 3, characterized in that: The viscous resistance coefficient and the inertial resistance coefficient are determined by the pressure drop of the porous medium material, the material thickness and the surface flow velocity.

8. The system for actively suppressing wind buffeting noise of automobile windows according to claim 3, characterized in that: The mesh diameter and porosity parameters are determined based on the pressure drop, thickness, surface flow velocity, air density and air viscosity of the porous medium material.

9. The system for actively suppressing wind buffeting noise of automobile windows according to claim 1, characterized in that: The control system continuously monitors the closing condition of the window sunshade system.

10. A vehicle, characterized in that: The invention comprises a system capable of actively suppressing wind buffeting noise of automobile windows as described in any one of claims 1 to 9.

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