Isolation element for a hydraulic vibration isolation module and hydraulic vibration isolation module equipped with said isolation element - Patents.com

Abstract

To provide: a separating element that broadens the range of vibration frequencies that are damped, while maintaining satisfactory damping action; and an anti-vibration hydraulic module equipped with such a separating element.SOLUTION: A separation element (22) is configured to separate a working chamber from a compensation chamber of a hydraulic anti-vibration module configured for mounting an engine on a vehicle body. The separation element includes a first duct (26) extending between a first mouth and a second mouth. The first mouth is provided in a first face of the separation element (22) and is configured to be fluidically connected to the working chamber, and the second mouth is provided in a second face of the separation element (22) and is configured to be fluidically connected to the compensation chamber. The first mouth includes a plurality of openings.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an isolation element for a hydraulic anti-vibration module for mounting an engine on a vehicle body, and to a hydraulic anti-vibration module equipped with such an isolation element. [Background technology]

[0002] An isolation device for mounting an engine on a vehicle body is known, which comprises a first frame connected to a second frame by means of a hydraulic isolation module which is deformable at least along a main axis of vibration.

[0003] However, known solutions only work within a narrow range of vibration frequencies. Summary of the Invention [Problem to be solved by the invention]

[0004] There is therefore a need to expand the range of vibration frequencies that are damped while still maintaining sufficient damping. [Means for solving the problem]

[0005] One embodiment relates to a separation element configured to separate an operating chamber from a compensation chamber of a hydraulic vibration isolation module configured for mounting an engine on a vehicle body, the separation element comprising a first duct extending between a first port and a second port, the first port being provided on a first surface of the separation element and configured to be fluidly connected to the operating chamber, the second port being provided on a second surface of the separation element and configured to be fluidly connected to the compensation chamber, the first port being divided into a plurality of openings.

[0006] In this disclosure, a port corresponds to an inlet or an outlet of a passageway configured to move a fluid. Depending on the direction of fluid flow, a port can be a fluid inlet or a fluid outlet.

[0007] The presence of a first port with multiple openings at the inlet of the first duct makes it possible to increase the fluid resistance and / or friction at the first port (and therefore the fluid resistance and / or friction of the first duct) compared to a single opening of the prior art. Increasing the friction makes it possible, on the one hand, to broaden the frequency range of vibrations damped by the hydraulic damping module and, on the other hand, to reduce the amplitude of the maximum amplitude vibration of the system seen at a given frequency of vibration of the fluid in the first duct. In other words, compared to a prior art separation element with a port with a single opening having a passage cross-sectional area comparable to or exceeding the multiple openings according to the present disclosure, the frequency range of the vibrations damped is broadened and at the same time sufficient damping is maintained over the entire frequency range of the vibrations damped.

[0008] It has further been found that when the first port comprises multiple openings, the bubbles generated by cavitation are disrupted into multiple smaller bubbles by the multiple openings in the first port, such that upon implosion, these smaller bubbles generate less sound / vibration than the implosion of larger bubbles found in prior art ducts.

[0009] Furthermore, implosions of large bubbles generate vibrations across the entire frequency spectrum, since the resulting volume change can be likened to a Dirac impulse, whose spectrum has a very wide range of excitation frequencies. In contrast, the implosions of many small bubbles of various diameters excite a different, more limited range of frequencies. As a result, these implosions of smaller cavitation bubbles generate smaller sounds / vibrations.

[0010] In some embodiments, the first port comprises a plate having a plurality of openings formed therein.

[0011] The first port can be manufactured separately from the separation element by adding a plate with a number of openings. The openings can be, but do not have to be, identical in size and / or shape. This makes it easier to adjust the frequency range of vibrations to be damped according to requirements.

[0012] In some embodiments, the first aperture comprises a grille.

[0013] The first port can be manufactured separately from the isolation element by adding a grating, which makes it easier to adjust the frequency range of vibrations to be damped according to requirements.

[0014] In some embodiments, the second duct extends between a third port provided on the first face of the separation element and configured to be fluidly connected to the actuation chamber, and a fourth port provided on the second face of the separation element and configured to be fluidly connected to the compensation chamber, preferably the third port comprises a single opening, and more preferably the diameter of the opening of the third port is larger than the diameter of any of the openings of the first port.

[0015] When a low friction duct (second duct) is combined with a higher friction duct (first duct), it is possible to increase the level of damping and at the same time increase the frequency range of vibrations that are damped.

[0016] In some embodiments, the second port and / or the fourth port each comprise a single (ie, only one) opening.

[0017] In some embodiments, the separation element comprises a body and a lid, the first duct and / or the second duct being a channel provided in a first surface of the body, further preferably the channel being covered by the lid.

[0018] The separating element is more easily manufactured. Indeed, by manufacturing a body with channels and a cover covering the channels, it becomes easier to manufacture the first and second ducts, while at the same time keeping the first and second ducts in the shape of a pipe when the cover is attached to the body. This approach is less technically restrictive than the design of a body with the first and second ducts inside in the form of a pipe, which are completely drilled into the body. This also makes it easier to adjust the damping.

[0019] In some embodiments, the first port and / or the third port are provided in the lid, and preferably the second port and / or the fourth port are fluidly connected to through holes extending from the second face of the body to the first / second duct, respectively.

[0020] This type of lid makes the isolation element easier to manufacture and assemble, and facilitates adjustment of the damping through the design of the lid aperture.

[0021] In some embodiments, the lid is circular in shape, and preferably a first element between the body and the lid comprises a recess and a second element between the body and the lid comprises a protrusion that aligns with the recess.

[0022] The recesses can be on the lid or the body and the protrusions on the body or the lid, respectively. This system forms a foolproof system that ensures proper fitting of the lid to the body, so that the port is correctly positioned relative to the duct, thereby providing better damping.

[0023] In some embodiments, at least one portion of the first duct extends in a straight line and parallel to at least one portion of the second duct, preferably at least one portion of the first duct is disposed between two portions of the second duct and / or, more preferably, at least one portion of the second duct is disposed between two portions of the first duct.

[0024] In other words, the first and second ducts can be intertwined within the separating element without crossing. This makes it possible to optimize the overall length of the ducts for the space given by the body. For example, the ducts can have a helical shape that helps to maximize the length of the straight parts and / or the overall length of the ducts within the smallest possible space and at the same time adapt them to the frequency range to be attenuated.

[0025] One embodiment also relates to a hydraulic vibration isolation module configured for mounting an engine on a vehicle body, comprising a working chamber, a compensation chamber, and a separation element according to any of the embodiments described in this disclosure, the separation element separating the compensation chamber and the working chamber.

[0026] The invention and its advantages will be better understood from reading the following detailed description of various embodiments of the invention given as non-limiting examples, the description making reference to the figures in the accompanying pages. [Brief description of the drawings]

[0027] [Figure 1] 1 is a cross-sectional view of an embodiment of an anti-vibration device. [Diagram 2] FIG. 2 is a view of the main body of the separation tool of the embodiment of FIG. 1. [Diagram 3] FIG. 2 is a view of a lid of the separation tool of the embodiment of FIG. 1. [Figure 4] FIG. 4 is a view of a first variant of the lid of FIG. 3; [Diagram 5] FIG. 2 is a view of a lid of a separation element known from the prior art. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] FIG. 1 shows a cross-sectional view of an isolation device 10 according to an embodiment. The isolation device 10 comprises a support 12 with a recess for accommodating a hydraulic isolation module 14, also known to those skilled in the art as a "hydromodule" or "hydromount". The support 12 is adapted to be fixed to a vehicle body or chassis. The hydraulic isolation module 14 comprises fixing means 16 by which the engine of the vehicle can be fixed. In the embodiment of FIG. 1, the fixing means 16 is hollow.

[0029] The hydraulic anti-vibration module 14 has a configuration known per se. As shown in Figure 1, the fastening means 16 are carried by an elastic body 18, for example made of an elastomeric material, which at least partially defines a working chamber 20. A separating element 22 is fixed to the elastic body 18. A compensating membrane 24 is fixed to the separating element 22. The compensating membrane 24 is deflectable but not stretchable and at least partially defines a compensation chamber 25.

[0030] The actuation chamber 20 is defined by the elastic body 18 and the isolation element 22. The compensation chamber 25 is defined by the isolation element 22 and the compensation membrane 24.

[0031] The working chamber 20 and the compensation chamber 25 are connected to each other by a first duct 26 and a second duct 28. Thus, when a force is applied to the elastic body 18, the elastic body 18 is compressed, thereby reducing the volume of the working chamber 20, whereby the hydraulic fluid present in the working chamber 20 flows through the first duct 26 and / or the second duct 28 towards the compensation chamber 25 and vice versa.

[0032] The configuration of the separation element 22 can be seen more clearly in Figures 2 and 3. The separation element 22 is generally cylindrical, the cylinder having a diameter, an axial direction and a circumferential direction. The separation element includes a body 30 having a first duct 26 and a second duct 28 extending therethrough.

[0033] The first duct 26 and the second duct 28 extend in a spiral shape around the axis of the separation element 22. More specifically, long portions of the first duct 26 and the second duct 28 (corresponding to at least 30% of the diameter of the separation element) extend parallel to each other, whereby at least one portion of the first duct 26 is arranged between two portions of the second duct 28. Conversely, at least one portion of the second duct 28 is arranged between two portions of the first duct 26. Moreover, at least one portion of the first duct 26 extends in a straight line and parallel to at least one portion of the second duct 28. In particular, the straight portion is again arranged as described above, i.e. between the two respective portions of the other duct 26 or 28.

[0034] The first duct 26 and the second duct 28 establish a fluid connection between the working chamber 20 and the compensation chamber 25. To that end, the first duct 26 comprises a first port 34 and a second port. The first port 34 corresponds to the inlet from the working chamber 20 to the first duct 26, and the second port corresponds to the inlet from the first duct 26 to the compensation chamber 25. The second duct 28 comprises a third port 36 and a fourth port. The third port corresponds to the inlet from the working chamber 20 to the second duct 28, and the fourth port corresponds to the inlet from the second duct 28 to the compensation chamber 25.

[0035] Thus, the first port 34 and the third port 36 are arranged on a first side of the separation element 22 facing the working chamber 20. The second port and the fourth port are arranged on a second side of the separation element 22 facing the compensation chamber 25. The second port and the fourth port are arranged at the outlets of the first duct 26 and the second duct 28, respectively.

[0036] The first duct 26 and the second duct 28 are channels carved out of the body 30 and open on the first face. In particular, the channels have a rectangular cross section in a section perpendicular to the plane of the first face and including the axis of the body 30. In order for the first duct 26 and the second duct 28 to have a tubular structure, the channels are closed by a lid 32. The lid 32 is thus arranged along the first face of the body 30. On the other hand, it is also possible to drill the entire first duct 26 and the second duct 28 in the body 30 with the same tubular structure, without closing said structure with a lid 32.

[0037] In this embodiment, the first port 34 and the third port 36 are openings in the lid 32. More generally, the first port 34 and the third port may comprise a plate. The plate may be a perforated plate with a plurality of openings. In some configurations, the plate may be replaced by a grid.

[0038] The second and fourth ports are provided in the body 30 and are not shown in the figures.

[0039] As shown in Fig. 3, the first port 34 comprises a number of small openings, and the third port 36 consists of a single large opening. In this embodiment, the first port 34 with its multiple openings replaces the known prior art inlet of the first duct 26 with a single opening (e.g. similar to the opening of the third port 36). This can be achieved, for example, by drilling holes in the lid 32 to create a number of small openings located at the position of the first port of the prior art. In this embodiment, the diameter of the opening of the third port 36 is larger than the diameter of any of the openings of the first port 34.

[0040] In some embodiments not shown, instead of multiple openings arranged in the lid 32, the first port 34 may comprise a large opening, for example similar to the opening of the third port 36, covered by a grid.

[0041] The second and fourth ports may, for example, comprise large openings similar to the opening of the third port.

[0042] For example, it is possible to satisfy the posed technical task by covering only the first duct 26 with the lid 32 according to this embodiment. In particular, it is possible to use a lid 32 as shown in Fig. 4, which does not comprise the third port 36, but only the first port 34. In this case, it is possible to omit the second duct 28.

[0043] The lid 32 is circular, as is the body 30 with which it cooperates. In the example embodiment of Figures 3, 4, and 5, a recess 40 is disposed on the lid 32 and a protrusion 38 is disposed on the body 30. The protrusion 38 and the recess 40 are configured to cooperate by matching shapes. If the body 30 and / or lid 32 are not circular, orientation can be ensured separately in a configuration in which the recess 40 and protrusion 38 are not required.

[0044] Although the present invention has been described with reference to specific embodiments, it is apparent that modifications and variations can be made to those examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the various illustrated / mentioned embodiments can be combined in yet further embodiments. The present specification and drawings should therefore be regarded as illustrative rather than restrictive.

[0045] It will also be apparent that all features described with respect to the method, either alone or in any combination, may also be applied to the apparatus, and vice versa, and all features described with respect to the apparatus, either alone or in any combination, may also be applied to the method.

Claims

1. A separation element configured to separate a working chamber from a compensation chamber of a hydraulic anti-vibration module configured for mounting an engine on a vehicle body, the separation element comprising: a first duct extending between the first port and the second port; the first port is provided on a first surface of a separation element and is configured to be fluidly connected to the working chamber; the second port is provided on a second surface of the separation element and configured to be fluidly connected to the compensation chamber; the first port comprises a plurality of openings; A separation element having a second duct extending between a third port disposed on the first surface of the separation element and configured to be fluidly connected to the working chamber, and a fourth port disposed on the second surface of the separation element and configured to be fluidly connected to the compensation chamber.

2. The separation element of claim 1 , wherein the first port comprises a plate having the plurality of openings disposed therein.

3. The separation element of claim 1 , wherein the first port comprises a grate.

4. The third port has a single opening, or 4. A separation element according to claim 1, wherein the diameter of the opening of the third port is greater than the diameter of any of the openings of the first port.

5. A separation element according to claim 1 , wherein the second port and / or the fourth port each comprise a single opening.

6. The separation element according to any one of claims 1 to 5, comprising a body and a lid.

7. The separation element according to claim 6 , wherein the first port and / or the third port is provided in the lid.

8. 8. A separation element according to claim 6 or 7, wherein the lid is circular in shape.

9. 9. A separation element according to claim 4, wherein at least one portion of the first duct extends straight and parallel to at least one portion of the second duct.

10. 1. A hydraulic vibration isolation module configured for mounting an engine on a vehicle body, comprising: A working chamber; A compensation chamber; A separation element according to any one of claims 1 to 9; Equipped with A hydraulic anti-vibration module, wherein the isolation element separates the compensation chamber and the working chamber.

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