Anti-vibration device comprising an elastomeric element elastically deformable with piezoelectric properties

Abstract

Anti-vibration device (T, T1, T2) comprising a first and a second body (1, 3) longitudinally spaced and having respectively a first and a second stiffness, and comprising respectively a first and second face (la, 2a) facing each other so as to define a gap (4) between the first and second body, one of said first and second bodies being connectable for force transmission to a vibrating component, an elastically deformable elastomeric element (5) comprising a polymeric matrix and a material with piezoelectric properties embedded in the polymeric matrix, said elastomeric element being placed in the gap in contact with the first and second body, and having a third stiffness at least an order of magnitude lower than the first and second stiffness, a first and second electrical terminal (T1, T2) mounted respectively on the first and second body, the first and second body being made of electrically conductive material, such that in use a force applied by the vibrating component to one of the first or second body toward the other causes compression of the elastomeric element and the generation of an electrical signal based on such compression, detectable via the first and second electrical terminal.

Description

[0001] ANTI-VIBRATION DEVICE COMPRISING AN ELASTOMERIC ELEMENT ELASTICALLY DEFORMABLE WITH PIEZOELECTRIC PROPERTIES

[0002] DESCRIPTION

[0003] TECHNICAL FIELD

[0004] The present invention pertains to the field of antivibration devices and, in particular, to an antivibration device comprising an elastomeric element elastically deformable and having piezoelectric properties. The invention also relates to a method of manufacturing such an antivibration device.

[0005] PRIOR ART

[0006] In the field of antivibration devices, commercially available solutions are widespread which comprise a first and a second rigid element between which an elastically deformable element is interposed, e.g. rubber. In particular, such rigid elements may be perforated or have threaded portions so as to allow the device to be connected to a portion of a component which, in use, generates vibrations, e.g. an industrial machine, which in use applies axial and / or radial forces on said device that are in turn damped by the elastomeric element elastically deformable in order to counteract the transmission of such forces to other components connected in force transmission with the vibrating component. However, currently existing solutions provide for the use of elastically deformable elastomeric elements of a ‘passive’ type, meaning they can only achieve a damping effect of the stress, thus making it impossible for a user to know the intensity of the load acting on the antivibration device, nor the direction of the stress of said load, making it impossible, based on the construction configurations of current antivibration devices, to extract information to detect correct operation of a machine or any malfunction thereof.

[0007] There is therefore a longstanding need to develop simple and compact constructional solutions, through which it is possible not only to provide a damping effect but also to estimate the intensity of the force discharged onto the antivibration device, thereby detecting any malfunctions of the machine to which such antivibration device is connected. OBJECT AND SUMMARY OF THE INVENTION

[0008] The present invention aims to satisfy at least in part the above-mentioned needs, and this object is achieved by means of an antivibration device according to claim 1.

[0009] According to a preferred embodiment of the present invention, an antivibration device is presented having a simple and compact constructional configuration, through which it is not only possible to damp the stresses of a vibrating component, e.g. of an engine or an operating machine, but it is also possible to estimate, during use, the intensity, and preferably the direction of the stresses generated by said vibrating component. Advantageously, in this way it is possible to verify the operating state of a machine, thus benefiting from improved predictive maintenance of the machine itself, e.g. identifying when the machine is operating correctly, is about to operate abnormally, or presents malfunctions.

[0010] To achieve this result, as described in the following description, an antivibration device is presented comprising a first and a second body, preferably of annular shape, longitudinally spaced apart and having respectively a first and a second stiffness. Said first and second body are shaped so as to have a first and a second face facing each other and so as to define a gap between the first and the second body. For example, the second body is sleeve-shaped and has a maximum diameter smaller than the maximum diameter of the first body, also sleeve-shaped, so that the latter can be arranged longitudinally inside the first body. For example, when said first and second body are in place, the first and second peripheral face are radially spaced, thus defining a circumferential gap, having the desired thickness.

[0011] Moreover, one of said first and second body is connectable in force transmission to a vibrating component, e.g. through a hole or a portion of one of said first and second body, whose generated stress is intended to be damped.

[0012] In particular, to obtain such damping effect, the antivibration device described herein comprises an elastomeric element elastically deformable comprising a polymeric matrix and a material with piezoelectric properties embedded in the polymeric matrix. In particular, said elastomeric element is arranged in the gap, e.g. through a casting process and subsequent polymerization of the polymer matrix -based liquid compound, so as to be in contact with the first and the second body.

[0013] Moreover, the elastomeric element has a third stiffness at least one order of magnitude lower than the first and second stiffness respectively of the first and second body.

[0014] According to one aspect of the present invention, it is possible to exploit the elastomeric element to detect an electrical signal, preferably an electric voltage, when said element is deformed. In particular, to achieve this result, said antivibration device comprises a first and a second electrical terminal, e.g. a clamp or a connector, electrically connected respectively to the first and the second body, and the latter are made of electrically conductive material, so that in use they act as electrodes. In this way, when a force is applied by the vibrating component on one of the first and second body towards the other of the first and second body, a compression of the elastomeric element is caused. The higher stiffness of the bodies compared to the elastomeric element means that the first and second body have a deformation substantially negligible compared to that of the elastomeric element.

[0015] Based on the described construction configuration, the force acting on the stressed body presents a radial or axial component causing the squeezing of the elastomeric element. Since the elastomeric element has piezoelectric properties, its deformation generates an electrical signal, preferably an electric voltage, which can be detected via the first and second electrical terminal and received as input to an electronic control unit connected in data exchange with said antivibration device, wherein the control unit can be programmed to process said signal in order to estimate an intensity of the stress acting on the device.

[0016] DESCRIPTION OF THE DRAWINGS

[0017] The constructional and functional features of the antivibration device can be better understood from the following detailed description, in which reference is made to the attached figures which represent a preferred and non-limiting embodiment thereof, in which:

[0018] Fig. 1 shows an axonometric view of an antivibration device according to a first preferred embodiment of the present invention;

[0019] Fig. 2 shows a cross-sectional view of the antivibration device of Fig. 1.

[0020] Fig. 3 shows an axonometric view of a vibration -damping device according to a second preferred embodiment of the present invention;

[0021] Fig. 4 shows a cross-sectional view of the vibration-damping device of Fig. 3;

[0022] Fig. 5 shows an axonometric view of a vibration-damping device according to a third preferred embodiment of the present invention;

[0023] Fig. 6 shows a cross-sectional view of the vibration-damping device of Fig. 5;

[0024] Fig. 7 shows an exploded view of the outer body of the vibration -damping device of Fig. 5;

[0025] Fig. 8 shows an exploded view of the inner body of the vibration -damping device of Fig. 5;

[0026] Figs. 9—13 each show a sectional view of preferred constructional variants of the present invention.

[0027] DETAILED DESCRIPTION OF THE INVENTION

[0028] According to a preferred embodiment of the present invention, Fig. 1 shows a perspective view of a vibration-damping device T used to dampen the intensity of vibrations generated by a vibrating component, e.g. an engine or an operating machine, in various application sectors. For example, in the industrial field in die-casting and hot-forming machines, mineral extraction and processing machinery, construction and agricultural machinery applications, e.g. excavators, concrete mixers and other construction site machinery, tractors and agricultural equipment, woodworking machines, power generation machines, etc.

[0029] According to one aspect of the present invention, the vibration -damping device T shown in Fig. 1 has a constructional configuration such that it can not only dampen the intensity of the vibrations of a vibrating component connected to it in force transmission, but also estimate during use the intensity of the stresses generated by such vibrating component, either for predictive maintenance purposes of the machine itself, e.g. to identify when the machine is operating correctly or is about to operate abnormally, or for monitoring operating parameters, identifying whether certain operations are taking place correctly. For example, the vibration-damping device T may be positioned between the frame of a machine and the parts subjected to stress or vibration, or to isolate specific elements of a system from the rest of the vibrating system, e.g. the cabin isolation in operating machines.

[0030] In particular, to achieve this result, the vibration -damping device T comprises a first and a second body 1, 3, preferably both annular in shape and mutually concentric, which are arranged in a position longitudinally spaced along an axis X. Preferably, as shown in Figs. 1 and 2, the first body 1 has a longitudinal cavity 2 made in a converging manner and whose surface defines a first peripheral face la of the first body. Preferably, this cavity is a conical hole with axis X that extends along at least one axial section of the first body.

[0031] The second body 3 is instead shaped longitudinally in a converging manner and has a maximum diameter smaller than the maximum diameter of the first body 1, so that it can be arranged in use inside the cavity 2. Based on this constructional configuration, when the second body 3 is axially arranged at least partially inside the cavity 2, it is radially spaced from the first body 1, particularly presenting a second peripheral face 2a, i.e. the one with the converging profile, facing the first peripheral face la. In particular, the first and second peripheral faces la, 2a are radially spaced and extend transversely with respect to a median plane, e.g. passing through the axis X, thus defining a gap 4 between the first and second bodies 1, 3.

[0032] According to a further aspect of the present invention, in order to maintain the first and second bodies 1, 3 transversely spaced from each other, the vibration-damping device T comprises an elastically deformable elastomeric element 5 arranged in the gap 4 in contact with the first and second bodies 1, 3. In particular, this elastically deformable elastomeric element is shaped so that when it is interposed between the first and second bodies 1, 3, i.e. engaged within the cavity 2, it defines with the latter a first form fit, e.g. the elastomeric element has a first inclined face 5a resting on the converging surface of the first body 1 and a second inclined face 5b, radially opposite to the first face 5a toward axis X, on which rests the converging surface of the second body 3, thereby defining a second form fit.

[0033] Preferably, the second body 3 also has a hole 6 made parallel to the axis X, and preferably coaxially, into which in use a portion of the component connected to the machine, of which the generated vibration is to be damped, is rigidly mounted. Alternatively, this hole can be made in the first body 1, or in both, to connect two separate components between which it is intended to dampen a stress generated by one of the two components.

[0034] According to a further aspect of the present invention, the elastically deformable elastomeric element has piezoelectric properties, and this characteristic is exploited in use to estimate the intensity of the stress from the vibrating component connected to the vibrationdamping device T. For example, the elastically deformable elastomeric element 5 is made by casting into an open-mold a solution comprising an elastomeric material, e.g. thermosetting, thermoplastic, chemically-reactive polymerizing, etc., such as a two-component liquid silicone, preferably but not limitedly polymerizing at room temperature, and a powder with piezoelectric properties embedded in the elastomeric material, e.g. ceramic powder.

[0035] Preferably, in order to provide a detectable and processable piezoelectric response so that the mechanical stress can be estimated, the piezoelectric powder content is equal to or greater than 15% by weight. For example, a usable ceramic powder can preferably but not limitedly be BaTiOs (barium titanate) .

[0036] The mold into which the compound is cast preferably comprises a plastic base electrically insulating and two electrodes fixed to said base. It should be noted that simultaneously with the polymerization of the compound in the mold, polarization of the ceramic powder dispersed in the solution occurs: to obtain this result, the electrodes are powered with high voltage, e.g. 4 kV, to generate an electric field that aligns the dipoles in a predetermined direction, in order to provide piezoelectric properties to the elastomeric element once solidified.

[0037] Alternatively, the mold may preferably be defined by the first and second bodies 1, 3 arranged in the spaced position they must have in a working configuration, so that the liquid compound can be cast into the gap 4 and subsequently polymerized.

[0038] It should also be noted that the first and second bodies are made of electrically conductive material, so that during the polymerization of the compound, the high voltage is applied directly to the first and second bodies, which in this case define the electrodes. Once the compound is polymerized, the elastomeric material solidifies remaining stably fixed to the peripheral faces la, 2a of the first and second bodies 1, 3 respectively. The process exploits the polarization of the particles while the compound is in a liquid phase, facilitating the alignment of the dipoles. At the end of the polymerization, the compound is solid, and the dipoles remain oriented in the desired direction even after removal of the electric field.

[0039] Therefore, based on the constructional configuration of the vibration-damping device, a force applied in use by the vibrating component on the second body 3 toward the first body 1, i.e. toward its converging end, causes compression of the elastomeric element 5 against the first body 1, and in particular a crushing and the generation of an electric voltage signal based on such deformation, detectable as a differential signal between the first and second bodies.

[0040] Alternatively, a comparable result is obtained when the vibrating component is connected in force transmission to the first body 1, and a force is applied to said first body toward the second body 3. In particular, in order to generate an electric voltage, the deformation of the elastomeric element causes a variation in the orientation of the electric dipoles and the consequent formation of an electric field, wherein negative and positive charges are arranged on opposite sides of the elastomeric element, e.g. on the side of the first and second bodies, so as to positively and negatively charge the first and second bodies 1, 3 and thus allow detection of the generated electric voltage signal. It should therefore be noted that, in order to achieve this result, the elastomeric element 5 exhibits a third stiffness that is at least one order of magnitude lower than the first and second stiffnesses of the first and second bodies, respectively. Preferably, the electric voltage signal is proportional to the deformation of the elastomeric element 5. Consequently, the elastomeric element 5 is capable both of damping the intensity of the vibrations of the vibrating component connected to it, and of providing an electric voltage signal across its polarized thickness.

[0041] For instance, when a load having an axial component is transmitted to the elastomeric element 5, the latter, upon deforming, exhibits opposite electrical polarizations on its end faces — i.e., those in contact with the first and second bodies 1, 3. This differential polarization defines an electrical potential difference that remains until electrostatic equilibrium is re-established through a closed circuit between the faces, over a period of time depending on the characteristics of the circuit itself.

[0042] Advantageously, the constructional configuration of Figs. 1 and 2, where the first and second bodies 1, 3 have respective converging surfaces in contact with the elastomeric element 5, ensures a larger contact surface, thereby increasing the intensity of the electric voltage signal provided by the elastomeric element 5. Furthermore, this constructional configuration counteracts misalignment between the first and second bodies 1, 3.

[0043] Preferably, as shown in Figs. 9—13, the first and second peripheral faces are equidistant along the entire longitudinal extension of the gap 4, but alternative solutions can be provided where the gap 4 has a converging profile toward one of the two longitudinal ends of the anti -vibration device T.

[0044] According to a further embodiment, the cavity 2 of the first body 1 may include a bottom surface with a rounded profile, while the second body 3 may include a head portion also with a rounded profile, such rounded profiles facing each other. Alternatively, the anti-vibration device T may have a different constructional configuration, in which, for example, the first and second peripheral faces la, 2a extend transversely in a mutually parallel manner, and preferably perpendicularly to axis X, or one of the first and second peripheral faces la, 2a extends at an incline relative to axis X in the longitudinal extension direction of the gap 4, while the other extends transversely and preferably perpendicularly to axis X.

[0045] Advantageously, the ring shape of the first and second bodies also facilitates easy coupling with a pin or tapping for a screw-thread coupling. As can be understood, the anti-vibration device proves particularly advantageous in applications where the stress varies over time, such that, by processing the resulting voltage signal, the intensity of the stress transmitted by the vibrating component can be estimated.

[0046] According to another aspect of the present invention, to detect the electric signal generated as a result of deformation of the elastomeric element 5, the anti-vibration device includes a first and a second electrical terminal Zl, Z2, e.g., a terminal block or connector, respectively on board the first and second bodies 1, 3. In particular, these electrical terminals are configured to be connectable in use to electrically conductive elements, such as electrical cables for data transmission, which in turn may be connected to an electronic control unit programmed to process the detected electric signal and output the corresponding stress calculation. The presence of the first and second electrical terminals Zl, Z2 is particularly advantageous since, during installation of the device on machinery, it is sufficient to connect electrical cables for data transmission to the terminals, which can then be connected to an electronic control unit either on board or remote from the machinery, e.g., on a computer in a control room of the factory machinery.

[0047] Advantageously, the presence of the first and second terminals Zl, Z2 facilitates electrical connection operations by a user between the anti-vibration device and the electronic control unit, e.g., by using commercially available standard clamps and connectors, especially when the antivibration device is installed in hard-to-reach or inconvenient locations on the machinery.

[0048] Preferably, though not necessarily, the anti-vibration device T is provided with the terminals already connected to the electrically conductive elements, e.g., each soldered to the respective electrical terminal.

[0049] However, in order for the electronic control unit to process the electric signal generated by deformation so as to calculate the corresponding stress, a signal conditioning device (not shown in the figures) may be electrically interposed between the first and second terminals Zl, Z2 and the electronic control unit, to close the electrical circuit and define the rate at which electrostatic equilibrium is re-established between the electric charges in the elastomeric element 5.

[0050] For example, this signal conditioning device may include a resistor electrically connectable at its ends to the first and second bodies 1, 3, so as to detect the electric potential difference across said resistor. Advantageously, this resistor is also used to reduce noise irrelevant to the processing of the detected electric signal.

[0051] Moreover, this signal conditioning device may be connectable for data exchange output with the electronic control unit to transmit the conditioned electric voltage signal. Preferably, the signal conditioning device and its associated wiring may be provided as a kit along with the antivibration device T.

[0052] According to a further preferred embodiment of the present invention, the electronic control unit and the signal conditioning device may be integrated into the anti -vibration device itself, e.g., by the manufacturer of the anti-vibration device, with the device thus including a power port for supplying electricity to the electronic control unit and the conditioning device. In this case, the electronic control unit may include an output port connectable for data exchange, e.g., with a computer-based electronic control unit to provide processed or partially processed data for calculating stress.

[0053] The conditioned electrical signal may thus be input to a voltmeter or to an electronic control unit, e.g., via electrical cables, the latter being programmed to store the acquired data and process them to estimate parameters representative of the stress acting on the device.

[0054] Preferably, though not exclusively, the result of processing such data may be useful for detecting voltage peaks, estimating the frequency at which the anti-vibration device is stressed, distinguishing voltage peaks based on the equivalent circuit and thus the capacity of the elastically deformable elastomeric element 5 and the applied resistive load, converting the voltage value obtained into a force or mechanical stress value based on functions / mappings defined during testing or calibration of the device.

[0055] According to a further preferred embodiment of the present invention, in Figs. 3 and 4, T1 denotes a constructional variant of the anti -vibration device T shown in Figs. 1 and 2, through which it is possible to damp stresses caused by a vibrating component in both directions parallel to axis X. References to constructional features common to those in Figs. 1 and 2 retain the same numbering.

[0056] In particular, to achieve this result, the anti-vibration device T1 of Figs. 3 and 4 is made using a pair of anti-vibration devices T, each having the constructional configuration of device T shown in Fig. 1, but arranged symmetrically with respect to a transverse plane P, preferably perpendicular to axis X, located on the side where the gap 4 has the greater diameter.

[0057] In this way, the anti-vibration device T1 includes pairs of first bodies 1, F, and pairs of second bodies 2, 2’, extending along axis X symmetrically with respect to plane P, i.e., the gap 4 features a first and second converging profile extending in opposite longitudinal directions.

[0058] Preferably, in the case where the pair of second bodies 3, 3’ has a maximum diameter smaller than the minimum diameter of the cavity of the pair of bodies 1, 1’, the first and second pairs of bodies 1, 1’ and 2, 2’ may be manufactured as a single piece, while the elastically deformable elastomeric element 5 may be produced via casting, as previously described.

[0059] Preferably, in the case where the pair of second bodies 2, 2’ has a maximum diameter larger than the minimum diameter of the cavity of the pair of bodies 1, 1’, the anti-vibration device Tl must be manufactured in two separate portions — an upper portion Tl’ and a lower portion Tl” — and then assembled. In this way, through this dual-convergence configuration, it is possible to dampen stresses transmitted by a vibrating component and thus detect the intensity of the oscillation; however, it is not possible to detect the direction of said stress.

[0060] According to a further preferred embodiment of the present invention, shown in Figures 5 and 6, an anti-vibration device T2 is depicted with a further improved constructional configuration, capable of providing, in addition to the aforementioned benefits, the added advantage of estimating the direction of the stress acting on the device. References to structural features that are common with those shown in Figures 1^1 retain the same numbering.

[0061] To achieve this result, the anti -vibration device T2 features a structural configuration comparable to that shown in Figures 3 and 4, with an upper portion T2' and a lower portion T2", although configurations similar to those in Figures 1 and 2 may also be used.

[0062] In particular, as shown in more detail in Figure 6, the upper and lower portions T2', T2" have a construction similar to that of the first bodies 1, 1' of the embodiment shown in Figures 3 and 4. Specifically, these upper and lower portions are angularly subdivided into first electrically conductive sectors 10, 10', and first electrically insulating sectors 10", each interposed angularly between two electrically conductive sectors.

[0063] For instance, the first electrically insulating sectors 10" are made using first electrically insulating elements 11, e.g., made of polymeric material, shaped like circular sectors extending symmetrically from a ring 7 substantially aligned with plane P and converging toward axis X.

[0064] As shown in Figure 7, these first electrically insulating elements 11 are angularly spaced apart, e.g., by 120 degrees, thereby defining radial housings 8 for first electrically conductive elements 9a, 9b, e.g., metal elements, which are used to form the first electrically conductive sectors 10, 10' (Figure 7).

[0065] Preferably, based on this construction, the first electrically conductive sectors 10, 10' can be obtained by radially inserting upper electrically conductive elements 9a into the radial housings 8 of the upper portion T2' of the anti-vibration device, and lower electrically conductive elements 9b into the radial housings 8 of the lower portion T2".

[0066] Additionally, the upper and lower electrically conductive elements 9a, 9b are shaped so that, when inserted into their respective radial housings 8, they form a shape-fit coupling with the first electrically insulating elements 11. For example, the upper and lower electrically conductive elements 9a, 9b also have a converging longitudinal profile in the same direction as the first electrically insulating elements 11. This feature not only promotes shape-fit coupling but also prevents the electrically conductive elements from disengaging from the radial housings 8 under the action of mechanical stress during use.

[0067] In particular, the converging profile of the walls of the electrically conductive elements in contact with the walls of the electrically insulating elements generates a radial component from a stress that causes the conductive element to be pressed against the wall of the insulating element 11, thereby preventing it from coming out of the corresponding housing.

[0068] Based on this same principle, the first electrically conductive sectors 10, 10' and the first electrically insulating sectors 10" are shaped with a transversely converging profile, preferably perpendicular to axis X, in a direction away from this axis, so that, to install the electrically conductive elements 9a, 9b, they must be placed in a space between the first electrically insulating elements 11 and to engage each electrically conductive element in a corresponding radial housing 8 pushing radially away from axis X.

[0069] Moreover, the first electrically conductive sectors 10, 10' have edges facing axis X shaped in an arc to define, when the anti-vibration device T2 is in place, an opening for access to hole 6, which is used to mount the vibrating component.

[0070] Furthermore, the electrically conductive and insulating elements have surfaces facing axis X that are inclined in such a way that, when installed, they define cavity 2, which extends convergently with respect to plane P in an axial direction from said plane.

[0071] According to a further aspect of the present invention, the upper and lower portions T2', T2" respectively have a construction comparable to the second bodies 2, 2' of Figures 3 and 4. In particular, as shown in Figure 8, these upper and lower portions are angularly subdivided into second electrically conductive sectors 20, 20', and second electrically insulating sectors 20", each interposed angularly between two electrically conductive sectors.

[0072] For example, the second electrically insulating sectors 20" are made using second electrically insulating elements 13, e.g., of polymeric material, having a shape that extends symmetrically from a second ring 12, also substantially aligned with plane P and diverging from axis X in an axial direction from this plane.

[0073] Additionally, these second insulating elements feature an inclined surface 13a extending convergently from the outer radial edge of the second ring 12, and a substantially straight surface 13b extending from the inner radial edge of said ring.

[0074] These second electrically insulating elements are angularly spaced, e.g., by 120 degrees, thereby defining second radial housings 14 for second electrically conductive elements, e.g., in metal, which are used to form the second electrically conductive sectors 20, 20' (Figure 8).

[0075] Preferably, based on this structural configuration, the second electrically conductive sectors 20, 20' can be formed by radially inserting upper second electrically conductive elements 15a into the second radial housings 14 of the upper portion T2' of the anti -vibration device, and lower second electrically conductive elements 15b into the second radial housings 14 of the lower portion T2".

[0076] Furthermore, the upper and lower second electrically conductive elements 15a, 15b are shaped so that, when inserted into their respective radial housings 14, they form a shape -fit coupling with the second electrically insulating elements 13.

[0077] For example, the upper and lower second electrically conductive elements 15a, 15b also have a converging longitudinal profile in the same direction as the second electrically insulating elements 13. This feature not only facilitates shape coupling but also prevents the second electrically conductive elements from disengaging from the second radial housings 14 under axial stress during use.

[0078] In particular, the converging profile of the walls of the second electrically conductive elements in contact with the walls of the second electrically insulating elements generates a radial component from an applied stress that compresses the conductive element against the wall of the insulating element, thereby preventing it from coming out of the corresponding housing.

[0079] According to the same principle just described, the second electrically conductive sectors 20, 20' and second electrically insulating sectors 20" are shaped with a divergent profile transversely and perpendicularly to axis X, in a direction away from this axis. As a result, to insert the second electrically conductive elements 15a, 15b into a housing, they must be positioned radially opposite axis X relative to the housing and then moved radially toward axis X to be engaged into the corresponding radial housing 14.

[0080] Moreover, the second electrically conductive sectors 20, 20' have edges facing axis X shaped in an arc so as to define, together with the edges of the second electrically insulating sectors 20", the hole 6 for mounting the vibrating component when the anti -vibration device T2 is in operation.

[0081] Thus, when the anti-vibration device is in use, the second electrically conductive and insulating elements have surfaces located radially outward from axis X that are inclined and radially spaced from the inclined surfaces defined by the first electrically conductive and insulating elements, thereby defining the gap 4 into which the elastically deformable element 5 with piezoelectric properties is placed.

[0082] It should also be noted that, when the anti-vibration device T2 is assembled, the first and second electrically conductive elements are arranged in a radially opposing position relative to the elastically deformable element 5, and in particular are in contact with the radially opposite inclined surfaces of said elastically deformable element. This means that, in the absence of the elastically deformable element 5 within the cavity 4, the first and second electrically conductive elements exhibit facing inclined surfaces in a radial direction. Consequently, the first and second electrically insulating elements are also arranged based on the same structural configuration. In this way, pairs of first and second electrically conductive sectors are defined, angularly separated from each other by pairs of first and second electrically insulating sectors.

[0083] Therefore, based on this structural configuration, each pair of first and second electrically conductive sectors acts as electrodes which are electrically insulated from the other electrodes defined by the other sectors. As in the embodiment of Fig. 3 and 4, in the case where the second body 3 has a diameter greater than the minimum diameter of the first body 1, the first and second electrically insulating elements 10", 20" that support the electrodes are manufactured via additive manufacturing, already assembled one inside the other.

[0084] In this way, each electrically conductive sector defines a direction for transmitting a voltage signal generated by the deformation of the elastomeric, elastically deformable element 5 under the action of a load applied to the device by a vibrating component.

[0085] Preferably, the upper and lower portions T2', T2" of the anti -vibration device each include three electrically conductive sectors, so that the three directions of transmission of the voltage signal are representative, for example, of the directions of a Cartesian coordinate system. In this manner, in order to identify the direction of the stress generated by the vibrating component, six external electrodes and six internal electrodes are required, each with a respective first and second electrical terminal on board (Fig. 5 schematically shows only one pair of electrical terminals), so as to detect six differential voltage signals that can in turn be processed simultaneously to estimate the force or mechanical pressure values originating from each pair of electrodes, taking into account the predominant direction, and to calculate the final force vector using mathematical formulas known to experts in the field.

Claims

CLAIMS1. Anti-vibration device (T, Tl, T2) comprising: a first and a second body (1, 3) longitudinally spaced and having respectively a first and a second stiffness, and comprising respectively a first and a second face (la, 2a) facing each other so as to define a gap (4) between the first and second body, one of said first and second bodies being connectable for force transmission to a vibrating component, an elastically deformable elastomeric element (5) comprising a polymeric matrix and a material with piezoelectric properties embedded in the polymer matrix, said elastomeric element being arranged in the gap (4) in contact with the first and second body (1, 3), and having a third stiffness at least an order of magnitude lower than the first and second stiffness; a first and second electrical terminal (Tl, T2) electrically connected respectively to the first and second body (1, 3); and the first and second body (1, 3) being made of electrically conductive material, so that in use a force applied by the vibrating component to one of the first or second body toward the other causes compression of the elastomeric element (5) and the generation of an electrical signal based on such compression, detectable via the first and second electrical terminal.

2. Anti-vibration device according to claim 1, wherein the first body (1) comprises a cavity (2) extending in a convergent manner, and the second body (3) is longitudinally shaped in a convergent manner and arranged at least partially within the cavity (2) so as to be radially spaced from the surface of said cavity to define the gap (4).

3. Anti-vibration device according to claim 1 or 2, wherein the first and second body (1, 3) extend symmetrically with respect to a median plane (P), and the gap (4) has a profile that converges toward a first and a second end of the anti-vibration device, said ends being longitudinally opposite with respect to the median plane (P).

4. Anti-vibration device according to any of the preceding claims, wherein the first and second body (1, 3) comprise electrically conductive sectors (10, 10’; 20, 20’) and electrically insulating sectors (10”; 20”) extending radially, the electrically conductive sectors being angularly separated by an electrically insulating sector so as to define signal transmission directions for the electrical voltage signal, one for each electrically conductive sector, when a force transmitted by the vibratingcomponent generates a deformation of the elastomeric element (5).

5. Anti-vibration device according to claim 4, wherein each electrically conductive sector comprises a first and second electrically conductive element (9a, 9b; 15a, 15b) radially opposed relative to the elastomeric element (5), and each electrically insulating sector comprises a first and second electrically insulating element (11; 13) radially opposed relative to the elastically deformable element (5).

6. Anti-vibration device according to claim 5, wherein the first and second insulating elements are angularly spaced, defining first and second radial housing (8, 14) respectively for housing the first and second electrically conductive elements.

7. Anti-vibration device according to claim 6, wherein the first electrically conductive elements and the first electrically insulating elements have a longitudinal profile that is respectively convergent and divergent toward a longitudinal end of the anti -vibration device, thereby defining a first form-fit coupling.

8. Anti-vibration device according to claim 6, wherein the first electrically conductive elements (9a, 9b) and the first radial housing (8) have a cross-sectional profile relative to axis (X) that extends radially in a convergent manner, thereby defining a second form-fit coupling.

9. Anti-vibration device according to any of the preceding claims, wherein the material with piezoelectric properties comprises ceramic powder with a content equal to or greater than 15% by weight.

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