RU2490143C2 - Vehicle engine suspension hydraulic mount with acoustic function - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to automotive industry, particularly, top-rank cars exploiting acoustic vibrations for warning the drive about engine operating conditions. Hydraulic mount comprises top and bottom hydraulic chambers 5, 6 separated by baffle 7 including restricting channel 8, load bush 11, rubber-metal spring 4, air chamber 9 separated from bottom hydraulic chamber 8 by elastic diaphragm 10 and attachments 11, 12 to connect the mount with car body structural element and engine housing 2. Chamber 9 is communicated with driver cabin 19 and air tube 16, 18 housing separation diaphragm 14 and restricting regulator 21 with flow section varying depending upon engine load. Sound-transmitting absorbing baffle 20 made of porous material is arranged in tube 18 nearby its outlet end. Diaphragm 14 is arranged in extra hollow chamber integrated in tube 18. Low-frequency sound vibrations are directed from chamber 13 into engine compartment via restricting hole 25. Intrinsic frequency of free vibrations of diaphragm 14 in chamber 13 falls in the range of desirable warning sound.

EFFECT: higher quality of warning signal.

5 cl, 2 dwg

Description

The invention relates to mechanical engineering, in particular to transport engineering, and in particular to high-class cars using acoustic vibrations to inform the driver about the operating mode of the power unit (hereinafter CA).

In addition to the problem of the negative impact of high noise levels on human health, a significant effect of tonality and dynamics of sound was found both on the adequate perception of the vehicle (hereinafter ATS) in the traffic flow and on the safety of driving. Buyers, as a rule, want to see PBXs whose noise pattern matches the type of PBX and their perception of it. For many customers, the “acoustic image” and noise comfort is a seriously taken buying motive. The driving pleasure should be enhanced in the future by the development of internal noise of the telephone exchange with a specific, unique sound character typical of the chosen brand of telephone exchange, satisfying the personal expectations of customers.

Since the 90s, the Western European automotive industry has been actively seeking various methods and technical possibilities for designing the nature of the sound of automatic telephone exchanges. And if in the 90s such work was carried out more as part of the finishing work at the final stage of finalizing the serial automatic telephone exchange, then in the 2000s this approach it is already insufficient due to a sharp reduction in the time it takes to start production of new models. Increasingly shorter debugging periods with a small number of prototypes with the increasing use of simulation techniques require a strong consistent transfer of acoustic design into the early phase of the design of the exchange.

In recent years, great progress has been made both in reducing the external and internal noise of the telephone exchange. It is enough to say that the regulatory requirements for the external noise of automatic telephone exchanges have been tightened in Europe over 15 years by 10 times from 84 dB (A) (1980) to 74 dB (A) (1995). However, increasingly quiet exchanges can be potentially dangerous if they are not perceived adequately. This is typical, in particular, for “silent” electric vehicles (electric vehicles) and, for example, for automatic telephone exchanges operating on hydrogen fuel. Therefore, external noise, in particular, should not be very low and should provide a pedestrian warning function

With regard to the interior space, passengers expect a quieter and more pleasant noise from high-quality, comfortable telephone exchanges. At the same time, the sound level was supposed to rise in proportion to the number of revolutions of the SA, it should be free of resonances, without tonal components. Stress-free rides on the autobahn with the possibility of a relaxing conversation in the cabin (driver's cab) are inalienable comfort rights of clients. On the other hand, the noise of the CA contains information that is rather unknowingly accepted by the driver, is processed and supported by the movement of the vehicle (subliminal information from the sound signal on the number of revolutions of the CA, its acceleration and load). Therefore, too much noise reduction in the cabin (driver's cabin), taking into account its information value, is already irrational. With "complete silence" in the cabin, the driver does not receive information about the operation of the SA, nor about its speed mode, nor about acceleration. Visual information about the approach to the vehicle in front arrives too late and often can no longer prevent a collision.

Numerous attempts to create sound information about the operation of the SA using "artificial sound", the strength and spectrum of which would depend on the mode of operation of the SA using acoustic speakers installed in the cabin and controlled by complex computer systems, were made by leading European automotive companies in the 90s . They were unsuccessful, because both the driver and passengers perceived the synthesized sound as artificial and did not psychologically perceive it as a signal from the SA, requiring an instant and immediate reaction. Since it is high-end automatic telephone exchanges that have low levels of sound vibrations in the internal passenger space, it is often relatively difficult for the driver to perceive the current load of the vehicle installed on the vehicle based on the noise of the vehicle transmitted to the passenger space. Therefore, it is relevant to increase the audibility and information content of SA sounds in the passenger space while maintaining low comfortable overall noise levels corresponding to the ATS class.

The solution to this problem required the "delivery" of natural sound and vibration signals coming directly from the CA and its systems. One of the promising areas that are widely studied in the West is the dosed transmission to the cabin (driver's cabin) of corrected signals from gas-dynamic systems through artificial acoustic and mechanical channels.

From patent information sources, for example, application DE 102007007946 (A1), IPC F01N 1/06, F01N 13/04, published on 09/04/2008; application US 2007029133 (A1), IPC F01N 13/04, F01N 1/02, F01N 1/06, published 02/08/2009 known device for registration of ATS noise regulating the sound emitted by the exhaust system into the surrounding space, so as to highlight (enhance) the noise of individual fundamental harmonics and subharmonics to create a sports image of the vehicle (sports sound). The sound transmitted to the ATS cabin simultaneously informs the driver and subconscious information about the operating mode of the SA and its speed, which according to the work (Bernd Fuchmann, Patrik Garcia, “Grundsalzuntersuchungen zum Sportsound durch Abgaskrümmer- und Vorrohranpassung", MTZ Motortechnische Teitschrift 62 (2001) 5, pp 356-366) has a positive effect on the safety of telephone exchanges on the road.

From the point of view of solving the problem of informing the driver, the disadvantage of the above devices (and similar) is the high noise levels emitted by the exhaust system into the environment, which leads to an increase in the total noise of the vehicle. This is especially true for high-end exchanges, with increased soundproofing of the cabin.

The device according to the patent US 6644436 (B2), IPC В60К 13/02 (+6), published on 10/31/2002, using noise transmission from the SA intake system directly to the passenger compartment through air ducts (tubes), containing separation membranes and hollows, is deprived of this disadvantage volumes for their placement and fixing, and acoustic regulation of the strength and spectrum of sound transmitted to the passenger compartment (passenger car space).

The disadvantage of the considered design, especially for turbo-charged ASs, is variable static pressures in the intake system, depending on the operating mode of the SA, variable static forces acting on the membranes, changing their stiffness characteristics and violating the stability of the sound transmission characteristics to the passenger compartment (stability of the transfer functions of the system) . Another significant drawback of the device is the possibility of foreign objects entering the clean air zone when the device is depressurized or broken.

The above-mentioned disadvantages of the considered analogues are largely eliminated by using the transmission of mechanical vibrations from the elastic supports of the CA suspension to the vehicle interior. The designs of such devices are known, for example, from the following sources of patent information: patent application DE 102005025577, IPC F16F 13/10, F16F 13/18, published December 7, 2006; patent application DE 102006003882, IPC F16F 13/10, B60K 5/12, published 02.08.2007; patent application DE 102004043334, IPC F16F 13/10, F16F 13/14, published 09.03.2006. All three of these analogues are structurally devices of hydraulic supports for the CA suspension and consist of the following main components: fasteners connecting the support with an element of the PBX body (body, subframe) and with CA, respectively; an elastic element and variously interacting hydraulic cavities separated by a partition, and sets of hydromechanical elements for regulating the dynamic forces transmitted to the vehicle body, which are then transmitted through the "mechanical bridges" to the cabin and create a sound field there. Supports also include conical throttling elements that regulate the passage sections of the internal channels and the dynamic characteristics of the support depending on the static deformation of the supports.

The disadvantages of these analogues include the limited paths and elements of the impact on the frequency characteristics of the transmission, since the regulatory elements act simultaneously on the low-frequency (main) characteristics of the support and its dynamic characteristics in the frequency range of informative sound. Another disadvantage is the complexity of controlling and regulating the transmission of oscillations along the body of the telephone exchange.

As a prototype, the device presented in patent application DE 102006058110, IPC F16F 13/18, F16F 13/10, published June 12, 2008, can be considered. The device described in the prototype, in particular, comprises a support housing, upper and lower hydraulic cavities formed inside the housing, separated by a partition containing a throttling channel, a load sleeve, a rubber-metal spring, an air cavity separated from the lower hydraulic cavity by an elastic membrane and attachment points connecting hydraulic support with a bearing element of the PBX case and the CA case.

However, the prototype is partially characterized by the same drawbacks that were already noted in the description of analogues and, in particular, the difficulty of controlling the transmission of sound through the body of the PBX.

These shortcomings are eliminated in the proposed (claimed) below design of the hydraulic support of the CA ATS endowed with an additional acoustic function, which provides technical means for converting the vibration signals generated by the CA into acoustic signals and transmitted (communicated) from the zone of the hydraulic support into a controlled comfort-information air acoustic a signal transmitted to the driver’s cab (passenger compartment) of the vehicle.

The technical result achieved by the present invention is to improve the quality of formation and perception of an adequate comfortable information acoustic signal by the hearing organs of the driver and passengers in the driver's cab (passenger room) of the vehicle.

The essence of the technical solution lies in the implementation of the set of essential features presented in the independent claim, and is achieved by the fact that in the known device of the hydraulic support of the CA ATC suspension with an acoustic function containing the upper and lower hydraulic cavities formed inside its body, separated by a partition containing a throttling channel , load sleeve, rubber-metal spring, air cavity separated from the lower hydraulic cavity by an elastic membrane and fasteners connecting the hydraulic support with the bearing element of the vehicle body and the power unit body, the air cavity of the support is acoustically connected to the driver's cab (passenger room) of the automatic telephone exchange with a connecting air tube into which the separation membrane and the throttle controller are integrated, changing its passage section depending on load mode CA. In the connecting air tube, near its output end, a sound-permeable absorbing element is placed in the form of a partition made of a porous mesh material, for example, Feldmetal. On the section of the air system, between the dividing membrane and the air cavity of the hydraulic support, a throttling hole is made, connected to the space of the engine compartment. The separation membrane is housed in an additional hollow volume integrated into the connecting air tube. The natural frequency of free vibrations of the separation membrane in the additional hollow volume lies in the current frequency range of the desired generated information sound.

Comparison and analysis of scientific, technical and patent documentation on the priority date in the main and related sections of the MKI shows that the set of essential features of the claimed solution was not previously known, therefore, it meets the patentability condition of “novelty”.

The analysis of known technical solutions in the art showed that the claimed device has features that are not available in the known technical solutions, and their use in the claimed combination of features makes it possible to obtain a new technical result, therefore, the proposed technical solution has an inventive step compared to the existing level technicians.

The proposed technical solution is industrially applicable, because can be manufactured industrially, efficiently, feasibly and reproducibly, therefore, meets the patentability condition “industrial applicability”.

Other features and advantages of the claimed invention will become apparent from the drawings and the following detailed description of the claimed device, where:

Figure 1 presents a diagram of a possible embodiment of the proposed hydraulic suspension support CA ATS with acoustic function;

Figure 2 presents a section of figure 1 by plane AA;

The device of the hydraulic support of the CA ATC suspension with the acoustic function shown in the drawings contains the actual hydraulic support 1 of the CA 2 suspension (at the same position 2 and ICE) to the element 3 of the ATC case, with a rubber-metal spring 4, upper 5 and lower 6 hydraulic cavities separated a partition 7 with a throttling channel 8, an air cavity 9, separated from the lower hydraulic cavity 6 by an elastic membrane 10, a load sleeve 11 connected to the attachment of the hydraulic support to the CA and the attachment 12, connecting the hyd Avalichny support 1 with an element 3 of the PBX building. The device further comprises a hollow tank 13, divided into two volumes by an air-blown dividing membrane 14, one of the volumes 15 of the hollow tank 13 being connected to the air cavity 9 of the hydraulic support 1 by a flexible air tube 16, and the second volume 17 of the hollow tank 13 is connected by the air tube 18 to the cabin driver (passenger space) 19 automatic telephone exchanges. In the air tube 18, near its output end, a sound-absorbing element 20 is placed in the form of a partition made of a porous mesh material (PSM), for example, Feldmetal, and the flexible air tube 16 is equipped with a regulator 21 for changing its flow area depending on the load mode CA.

The regulator 21 changes the flow cross section of the flexible air tube 16, as shown in figure 2, is made in the form of an elastic hose 22, partially pinched by mechanical clamps 23 and 24 depending on the static deformation of the hydraulic support 1 with a static spatial displacement CA 2. The clamp 23 is connected mechanically with a load sleeve 11 associated with the attachment of the hydraulic support to the CA, the clamp 24 - with the attachment 12 or with the housing 1.

The volume of the hollow tank 13 connected to the air cavity 9 of the hydraulic support 1 is acoustically communicated with the atmosphere through a calibrated hole 25.

The natural frequencies of the membrane 14 are selected close to the main harmonic of the internal combustion engine at speeds equal to about half the maximum speed of the internal combustion engine. The acoustic connection of the second volume 17 of the hollow tank 13 with the driver’s cabin (passenger room) 19 of the vehicle and / or with the engine compartment (not shown) and / or with the surrounding area and / or with the interior (interior) of the vehicle is at least partially using a flexible hollow cylindrical air tube 18. The acoustic connection of the volume 15 of the hollow tank 13 with the air cavity 9 of the hydraulic support 1 is made at least partially by means of a flexible (hollow cylindrical) air tube 16.

A compact sound-absorbing element 20 is placed in the air tube 18, in the form of a partition, which is made of a porous mesh (fibrous) sound-absorbing material, for example, of a porous mesh metal material (such as Feldmetal, Soiferite, etc.).

Under the influence of unbalanced internal forces of inertia and variable gas forces in the internal combustion engine cylinders, the latter vibrates on the hydraulic bearings 1 and these vibrations are transmitted mechanically to the vehicle body. To reduce vibration between the CA and the ATC case, flexible hydraulic bearings 1 are installed, significantly reducing the transmission of vibrations to the ATC case due to the flexibility of the rubber spring 4.

However, nevertheless, due to the flexibility of the rubber spring 4 (hereinafter referred to as the spring), the transmission of vibrations is not completely eliminated. The vibration transmission becomes especially strong when the frequencies of inertial forces coincide with the natural vibration frequencies of the SA on the hydraulic supports 1. To reduce vibrations, the hydraulic cavity of the hydraulic support 1 is divided into two hydraulic cavities 5 and 6 by a partition 7 with a throttling channel 8. When the CA is displaced, for example, down - the spring 4 compresses the liquid in the upper 5 hydraulic cavity of the hydraulic support 1 and pushes it into the lower hydraulic cavity 6 through the throttling channel 8. When punching kinetic energy Ia liquid partially dissipated (converted into thermal energy) and the resonant amplitude vibrations transmitted decreases.

Oscillations of the SA under the action of unbalanced internal forces cause the relative displacement of the CA relative to the body of the ATS and the corresponding relative displacements of the load sleeve 11 and the attachment point 12 of the hydraulic support 1 relative to each other. These displacements lead to displacements of the spring 4 relative to the housing of the support 1 and the squeezing of fluid from the upper 5 hydraulic cavity through the throttling channel 8 into the submembrane cavity (lower 6 hydraulic cavity). In turn, filling the lower (submembrane) hydraulic cavity 6 with liquid leads to the displacement of the elastic membrane 10, an increase in the dynamic pressure in the air cavity 9 and the vibrational extrusion of excess air into the flexible air tube 16. These vibrations are transmitted through the flexible air tube 16 to the hollow tank 13 and cause excitation of the sound pressure field in its volume. Oscillations of sound pressure, in turn, act on the separation membrane 14 and cause its vibrational movements and the corresponding compression-rarefaction in the volume. The sound pressure fluctuations in the second volume 17 of the hollow tank 13 cause gas to oscillate in the air tube 18, through which they are transmitted to the driver’s cab (passenger room) 19 of the vehicle. A sound-absorbing element 20 is installed in the air tube 18, affecting the acoustic characteristics of sound transmission and, in particular, reducing resonance vibrations in the air tube 18.

Through the calibrated hole 25, low-frequency sound vibrations are “taken away” from the hollow tank 13 negatively perceived by the “listeners” in the PBX cabin. The length (depth) of the calibrated hole 24 and its diameter are related by the ratio

The length (depth) of the calibrated hole 24 and its diameter are related by the ratio

$$\frac{{\omega }_{\mathrm{one}}{L}_{otv}}{\mathrm{from}}<<0.1\frac{F_{otv}}{F_{\mathrm{eighteen}}}$$

Where

F _otv and L _otv are the area and length of the calibrated hole (m ² and m, respectively), s is the speed of sound, F ₁₈ is the cross-sectional area of the air tube 18 (m ² ).

ω ₁ - System Configuration frequency generally equal to the fundamental frequency at the speed of 3500 min ^-1

намного меньше акустического сопротивления воздушной трубки 18, идущей в кабину водителя (пассажирское помещение) $$Z_{18}=\frac{\rho c}{F_{18}}$$

и низкочастотный звук уходит через отверстие.Moreover, for low frequencies (ω <ω ₁ ), the acoustic impedance of the hole $$Z_{otv}=\frac{\omega \rho L_{otv}}{F_{otv}}$$

much less than the acoustic impedance of the air tube 18 going into the driver’s cab (passenger compartment) $$Z_{\mathrm{eighteen}}=\frac{\rho c}{F_{\mathrm{eighteen}}}$$

and low-frequency sound goes through the hole.

The level and spectral composition of the comfort-informational sound signal entering the driver’s cabin (passenger room) 19 ATS is controlled by the appropriate acoustic settings of the elements of the sound transmission chain (lengths and diameters of flexible air 16 and air 18 tubes, acoustic characteristics of the elements, volumes, stiffness and resonant frequencies of the separation membrane 14, the possible installation of additional mechano-acoustic filters, in the form of an additional air cavity separated by two spaces with a flexible membrane, as well as automatic or manual adjustment of the length of the tubes, the rigidity of the membrane, and the installation of throttles.In the considered device (a special case of the design presented in the dependent claim 2 of the claims), a regulator 21 for changing the flow area of the flexible air tube 16 is provided , as shown in figure 2, which is made in the form of an elastic hose 22, partially pinched by mechanical clamps 23 and 24 depending on the static deformation of the hydraulic support 1 with a static spatial displacement CA 2.

Of course, the claimed invention is not limited to the specific structural examples of its implementation described in the text and shown in the accompanying figures. Some minor changes to the various elements or materials from which these elements are made, or to replace them with technically equivalent ones that do not go beyond the scope of the claims indicated by the claims, remain possible.

Claims (5)

1. The hydraulic support of the suspension of the power unit of a vehicle with an additional acoustic function, comprising upper and lower hydraulic cavities formed inside its body, separated by a partition containing a throttling channel, a load bush, a rubber spring, an air cavity separated from the lower hydraulic cavity by an elastic membrane and units fasteners connecting the hydraulic support with the bearing element of the vehicle body and the power unit housing, excellent yuschayasya that support air cavity is connected acoustically to the driver's cab (passenger area) of the vehicle connecting an air tube, which integrates separation membrane and a throttle control, changing its flow cross-section, depending on the load mode of the power unit. 2. The hydraulic support of the suspension of the power unit of a vehicle with an additional acoustic function according to claim 1, characterized in that in the connecting air tube, near its output end, a sound-absorbing absorbing element in the form of a partition made of a porous mesh material, for example Feldmetal, is placed. 3. The hydraulic support of the suspension of the power unit of a vehicle with an additional acoustic function according to claim 1, characterized in that a throttling hole is made in the section of the air system between the separation membrane and the air cavity of the support connected to the space of the engine compartment. 4. The hydraulic support of the suspension of the power unit of a vehicle with an acoustic function according to claim 1, characterized in that the separation membrane is placed in an additional hollow volume integrated into the connecting air tube. 5. The hydraulic support of the suspension of the power unit of the vehicle according to claim 4, characterized in that the natural frequency of free vibrations of the separation membrane in the additional hollow volume lies in the current frequency range of the desired generated information sound.

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