FR2605693A1 - Improvements to anti-vibration hydraulic supports - Google Patents

Abstract

The anti-vibration hydraulic support comprises a rigid annular framework 1, a rigid axisymmetric core 2 coaxial with the framework located inside the latter, three elastomer rings 3, 4, 5 connected in a sealed fashion on the inside to the core and on the outside to the framework so as to delimit between them two sealed annular chambers, a restricted passage causing the two annular chambers to communicate with each other, and a mass of liquid filling both the two chambers and the restricted passage. Each annular chamber is divided into two sealed compartments (respectively A, B; C, D) by two diametrically opposed elastomer radial partitions and the restricted passage is composed of two ducts 7, 8 each connecting one compartment of a chamber to the furthest compartment of the other chamber.

Description

Improvements to anti-vibration hydraulic supports.

 The invention relates to anti-vibration devices - called supports below - intended to be interposed for the purpose of damping and connection, or even real support, between two elements subjected individually to certain oscillations or vibrations, damping involving the discharge of a liquid through a strangled passage.

 The two elements to be joined together are, for example, a vehicle chassis and a member suspended relative to this chassis, such as the vehicle engine or a wheel thereof.

The invention relates more particularly, among the supports of the kind in question, those which comprise - a rigid annular framework which can be secured to one
of the two elements to be joined, - a rigid core of revolution coaxial with the framework,
located inside it and can be joined together with
the other element, - three elastomer rings tightly linked in
anterior to the core and externally to the framework
so as to delimit between them two annu
waterproof laires, - a strangled passage connecting the two cham
annular bres between them, - and a mass of liquid filling both
rooms and the strangled passage.

 With such a support, any axial stress exerted on one of the two rigid parts (annular framework and core) relative to the other results in the deformation of the elastic rings and therefore in the discharge of a portion of the liquid contained in one of the two rooms towards the other room through the strangled passage.

 The dimensions of said passage are determined as a function of the frequency F of the oscillations which it is desired to dampen as much as possible, so that the mass of liquid contained in the constricted passage, mass subjected to the oscillations imposed on the support, enters into resonance for the F value of the frequency of these last oscillations.

 Such a support has good resistance, with damping, to the stresses exerted on it in the axial direction, that is to say in the direction parallel to the axis common to the annular framework, the core and the rings.

 But it is not the same for the stresses exerted on this support in the radial directions.

 The object of the invention is, above all, to make the supports considered such that they remedy this drawback, that is to say that they also have good resistance with damping to the stresses exerted in a radial direction.

 To this end, the supports of the kind in question are essentially characterized according to the invention in that each of their two annular chambers is divided into two watertight compartments by two radial partitions made of diametrically opposite elastomers, the mean planes of the four radial partitions being merged in the same axial plane and in that the constricted passage is composed of two conduits each connecting a compartment of a room to the compartment furthest from the other room.

In preferred embodiments, use is also made of one and / or the other of the following arrangements - the support is composed of two half-supports including
each with an annular half-frame, a half-core
central, an extreme elastic ring, half of
central elastic ring and two elastic partitions
radial, - the nucleus is composed of two juxtaposed half-nuclei
axially against each other and crimped one on
the other by contiguous introduction of a rigid tube
in axially hollow cylindrical bores in
these half-cores and drawdown of the ends of this
tube outwards against said half-cores, - in a support according to any one of the two preceding
paragraph teeth, each conduit comprises on the one hand a
curved central section consisting of two semi grooves
circulars with angular extent less than 180
degrees hollowed out respectively in the faces in re
gard, of the two half-cores, juxtaposed axially
one against the other, and on the other hand two sections
connection terminals hollowed out respectively in
the two half-cores, - each of the four compartments defined above is
itself divided into two sealed halves by a partition
its elastomeric radial whose mean plane extends
perpendicular to the common mean plane of the partitions
above, and the strangled passage is composed
of four conduits each connecting one of the half
compartments thus produced in the half compartment the
further from the support.

 The invention includes, apart from these main provisions, certain other provisions which are preferably used at the same time and which will be more explicitly discussed below.

 In what follows, we will describe preferred embodiments of the invention with reference to the accompanying drawings in a manner of course not limiting.

 Figures 1 and 2r of these drawings show respectively in axial section along I-I, Figure 2, and in cross section along Il-Il, Figure 1, an anti-vibration support established according to the invention.

 Figure 3 shows in perspective view the assembly consisting of only elastomeric portions of said support.

 Figures 4 and 5 schematically show the deformed state of said support when are exerted on it stresses oriented respectively in the axial direction and in a radial direction.

In a manner known per se, the support considered comprises - a rigid annular frame 1, - a core of revolution 2 coaxial with the frame and dis
placed inside it, - three elastomer rings 3, 4 and 5 joined together so
waterproof, exterior, frame 1 and interior
ment, at core 2 and delimiting two chambers annulai
res, - a strangled passage making these two rooms communicate
bres between them, - and a liquid filling said chambers as well as
the strangled passage.

In addition, and in accordance with the invention - four radial elastomer partitions 6 divide each
one of the annular chambers in two compartments
identical (respectively A, B and C, D) extending cha
cun according to almost a semicircle, the average planes of
these four partitions 6 being combined into one and
same axial plane, - and the constricted passage ensuring communication between
the two chambers is constituted by two channels 7 and 8
connecting each of the four compartments A, B, C and D
to the compartment farthest from him.

 Thus the upper left compartment visible at A in FIG. 1 is connected by channel 7 to the lower right compartment D and that the upper right compartment B is connected by channel 8 to the lower left compartment C.

 These cross communications make it possible to extend the damping support effect to a radial direction which, in the previously known embodiments, was reserved for the axial direction only.

 Indeed, when a stress is exerted axially downwards on the central core 2, according to the arrow F in FIG. 4, the liquid contained in the lower compartments C and D is discharged with constriction, as in the embodiments of the prior art, to the upper compartments A and B, as indicated by the arrows, and vice versa.

 In addition, during the exercise, on the central core 2, of a radial stress directed towards the left according to the arrow G of FIG. 5, the liquid contained in the left compartments A and C is here driven back with throttling according to arrows q in the two right compartments B and D, and vice versa, whereas previously no phenomenon of this type was observable.

 The direction G considered is that which is perpendicular to the mean plane of the partitions 6.

 In the embodiment which has been illustrated in FIGS. 1 to 3, the support consists of two identical halves juxtaposed one against the other in the same transverse plane.

 Each of these two halves comprises - an outer annular half-frame 11,12, - a central half-core 21,22, - an extreme elastic ring 4 or 5, - an intermediate elastic half-ring - and two radial partitions 6.

 Each annular half-frame is in the form of a bowl whose bottom is largely perforated in its center and which is extended externally by two planar transverse legs 9 diametrically opposite.

 Each tab 9 is perforated with a light 10 suitable for receiving an assembly member such as a bolt-nut system or a rivet.

 Each half-core 21, 22 has the general shape of a half-ball whose external, stepped surface successively comprises a cylindrical section 11, two frustoconical sections 12 and 13 of increasing obliquities and a transverse plane section 14 and it is hollowed out by an axial cylindrical hole 15.

 The different elastomer elements included in each half-support, elements comprising an end ring, an intermediate half-ring and two radial partitions, are made up of a single, single piece molded part.

 Each ring, half-ring or partition 3,4,5,6 is directly adhered internally against the core 2 and externally on a perforated metal half-cage 161,162 arranged so as to coat only the external faces of said rings and partitions and even to be partially coated with the constituent elastomer of these rings and partitions.

Each channel 7,8 comprises - a semicircular central section extending over a
arc slightly less than 180 and delimited by two gor
holes hollowed out respectively in the two flat faces
transverse to juxtapose two half-cores, - and two hollow connections respectively in these half
cores and connecting the two ends respectively
from the semicircular section above to one of the four
compartments A, B, C and D and to the most compartment
distant from it.

 In other words, the channel 7 connects the two upper left A and lower right compartments D visible in FIG. 1 while the channel 8 connects the two upper right B and lower left C compartments together.

 To form the support composed of the two half-supports described above, we start by juxtaposing axially one against the other the two half-cores 21 and 22 on each of which is adhered externally an extreme ring 3 or 5 and a half-ring intermediate or 42. This juxtaposition is ensured so as to reconstitute the two central semi-circular sections belonging to channels 7 and 8.

 The two juxtaposed half-cores are then crimped against each other by jointly introducing a metal tube 17 into the two cylindrical holes 15 then aligned, then the slightly protruding ends 18 of this tube 17 are folded outwardly on the half-cores .

 It is then possible to weld one against the other juxtaposed radial flanges 19 terminating the linkages 161, 162 at the level of the central transverse plane.

 Then the assembly is capped by the two bowls and 12 constituting the external annular framework and these are assembled together by welding.

 The end rings 3 and 5 are firmly fixed to these bowls by their slight elastic crushing resulting from said assembly and, if necessary, by folding, against the facing edges of said bowls, end flanges 20 of cylindrical appearance. understood by the cage 16 or more precisely the half-holes 161, 162 making up this cage.

 As a result of this, and whatever the embodiment adopted, a hydraulic antivibration support is finally obtained having an excellent support and damping behavior not only in the axial direction thereof but also in a radial direction.

 As it goes without saying, and as it already follows from the foregoing, the invention is in no way limited to those of its modes of application and embodiments which have been more especially envisaged; on the contrary, it embraces all its variants.

 In particular, the excellent above-mentioned behavior of support and damping could be presented in two radial directions perpendicular to each other: for this purpose each of the four compartments above defined is divided into two watertight halves by a radial elastomer partition, the mean plane extends perpendicular to the common mean plane of the preceding partitions 6, and the passage is constricted by four conduits each connecting one of the half-compartments thus produced to the half-compartment furthest from the support.

 The support thus obtained offers good resistance with damping to the stresses exerted on it in two radial directions x, y perpendicular to each other and also in the axial direction z, that is to say ultimately in three directions of space x, y, z perpendicular two by two.

 The resistance with resulting damping can then be considered as "universal", that is to say obtained for any direction of stress, since any direction can be broken down into three components oriented respectively in the three directions x, y and z considered.

Claims (5)

 1. Hydraulic antivibration support intended to be interposed for the purpose of damping and of connection between two elements subjected individually to certain oscillations, damping involving the delivery of a liquid through a throttled passage, comprising a rigid annular framework (1 ) can be joined to one of the two elements to be joined, a rigid core of revolution (2) coaxial with the frame, located inside the frame and can be joined to the other element, three elastomer rings (3, 4,5) tightly linked internally to the core and externally to the framework so as to delimit between them two sealed annular chambers, a constricted passage making the two annular chambers communicate with each other and a mass of liquid filling both chambers and the constricted passage, characterized in that each of its two annular chambers is divided into two watertight compartments (respectively A, B; C, D) by two radial partitions in diametrically opposed elastomer (6), the mean planes of the four radial partitions being merged into the same axial plane and in that the constricted passage is composed of two conduits (7,8) each connecting a compartment of a chamber to the compartment further away from the other room.  2. Support according to claim 1, characterized in that it is composed of two half-supports each comprising an annular half-frame (I 1.12), a central half-core (21,22), an extreme elastic ring (3 , 5), a half of central elastic ring (41,42) and two radial partitions (6).  3. Support according to claim 2, characterized in that the core is composed of two half-cores (21,22) juxtaposed axially one against the other and crimped on each other by contiguous introduction of a rigid tube (17) in cylindrical bores (15) axially hollowed out in these half-cores and folding of the ends (18) of this tube towards the outside against said half-cores.  4. Support according to any one of claims 2 and 3, characterized in that each conduit (7,8) comprises on the one hand a curved central section constituted by two semi-circular grooves of angular extent less than 180 degrees hollowed out respectively in the opposite faces, of the two half-cores, juxtaposed axially one against the other, and on the other hand two terminal connection sections hollowed out respectively in the two half-cores.  5. Support according to any one of the preceding claims, characterized in that each of the four compartments defined above is itself divided into two sealed halves by a radial elastomer partition whose mean plane extends perpendicular to the mean plane common of the above partitions, and in that the constricted passage is composed of four conduits each connecting one of the half-compartments thus produced to the half-compartment furthest from the support.