FR2473662A1 - ELASTIC SUPPORT FOR SUSPENDING AN OSCILLATING BODY ON A CARRIER STRUCTURE, IN PARTICULAR AN ENGINE ON THE CHASSIS OF A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to an elastic support for suspending an oscillating body on a supporting structure, in particular an engine on the chassis of a motor vehicle. This support comprises a plate 1 having two wings 2 pierced for fixing to the frame, a cylindrical sleeve welded into a central opening of this plate, a sleeve 7 for fixing the engine and an intermediate block 5 of elastomer, fixed by vulcanization to the sleeve and the socket. This elastomeric block has 8-curved through slots, the concavities of which are turned outwards so as to ensure a more uniform distribution of the stresses. The invention applies to the fastening of motor vehicle engines. (CF DRAWING IN BOPI)

Description

The present invention relates to an elastic support for suspending a

  oscillating body on a supporting structure, in particular

  an engine on the chassis of a motor vehicle, such a support

  carrying a hollow connecting element, intended to be fixed to the supporting structure, a fixing element which is provided for fixing the oscillating body and is inserted in the cavity of the connecting element and an annular intermediate block, made of elastomer, having its inner surface attached to the fastener and its outer surface attached to the element

  and having two openings in the form of a curved slot,

  opposed, which are oriented axially and extend over all

the length of the elastomer block.

  The two openings formed in the elastomer block

  give the bloc a differentiated elasticity in terms of

  radial configurations, this elasticity being variable according to the direction the

  along which the deformation occurs.

  In use, elastic supports of this type are subjected to forces that vary in time, both in the axial direction and in the radial direction, and the elastomeric block is subjected to

  stress, its operational longevity being then determined

  undermined by both the total value of the forces it has to absorb and the way these forces are distributed within the material

constituting the block itself.

  It is therefore particularly necessary to avoid concentra-

  constraints and, in general, it is necessary to obtain a distribution

  constraints as uniform as possible.

  The object of the present invention is to obtain an elastic support of the type mentioned at the beginning, in which the conformation of the

  slots will be able to guarantee that this support has

  will have greater fatigue resistance than those used

  in the prior art, thus leading to a greater duration of use.

  tion. To achieve this object, the present invention provides an elastic support of the type mentioned at the beginning, characterized in that each of the slot-shaped openings has its concave surface directed

  to the outside of the elastomeric block.

  Preferably, the two slot-shaped openings are in the form of through holes whose cross sections are of dimensions

  substantially constant over the entire length of the elastometer block.

  In a particular embodiment, each of the openings

  tures in the elastomer block has a significant part of its

  profile that is tangent to a plane passing through the axis of the support.

  In another embodiment of the invention, the two slot-shaped openings are symmetrically arranged with respect to a plane of symmetry of the fastener element and each have two arcuate portions, the concavities of which are turned towards the outside of the block, and a curved central portion connecting these

two bow-shaped portions.

  The invention will be better understood and other features

  will appear with the following description and accompanying drawings

  o: - Figure 1 is a plan view of a support or elastic mount according to a first embodiment of the invention; FIG. 2 is a sectional view taken along an axial plane passing through the line II-II of FIG. 1; FIG. 3 represents a first variant embodiment of the invention, seen in a section similar to that of FIG. FIG. 2 - FIG. 4 is a view, from a point of view similar to that of

  FIG. 1, showing a second variant embodiment of the invention

  FIG. 5 is a view, from a point of view similar to that of

  FIGS. 1 and 4, showing a third embodiment variant of -

  the invention; FIG. 6 is an axial sectional view taken along the line VI-VI of FIG. 5;

  FIG. 7 is a front view of a fourth variant of embodiment

of the invention

  - Figure 8 is a side view, partially cut according to the-

line VIII-VIII of Figure 7; -

  FIG. 9 is a view, from a point of view similar to that of FIGS. 1, 4 and 5, showing a fifth variant embodiment of the invention; and FIG. 10 is an axial sectional view taken along line X-X of FIG.

Figure 9.

  In Figures 1 and 2, reference numeral 1 generally designates a plate having two opposite wings 2 provided with holes 3 which serve to fix this plate 1 to the chassis of a motor vehicle. The plate i has a central opening in which a cylindrical sleeve 4, whose outer surface is fixed, is welded by welding its intermediate part to the edge of the opening in the

  plate 1. At the inside surface of sleeve -4, is fixed by vulcani-

  the outer lateral surface of an annular block 5 made of elastomer, having the shape of a cylinder whose end faces 6 are

  slightly convex towards the outside.

  The inner surface of the elastomeric block 5 is fixed, by vulcanization, to the outer surface of a hollow cylindrical pin 7

  which is coaxial with the sleeve 4 and which has an axial dimension ltgè-

  This hollow spindle 7 is adapted to receive, when used, a corresponding member.

  for fixing the engine of a vehicle.

  The elastomer block 5 is provided with two diameters

  three opposing shaped curved slot 8 whose concave surfaces are facing outwardly of the block 5. These two openings 8 are holes through the block 5, axially directed and having substantially constant dimensions along the entire length of the block. In addition, as clearly shown in FIG. 1, the openings 8 are formed in zones of the block 5 situated in front of the fixing wings 2

of the plate 1.

  The layout and shape of the openings 8, coebines with the

  structure of the elastomer block 5, allow the assembly according to the invention

  to offer better resistance to fatigue than frames

  classics of this type, resulting in increased support longevity.

  During tests carried out by the plaintiff, he found out,

  surprisingly, that the support according to the invention could easily

  endurance of up to five hundred thousand fatigue test cycles without evidence of cracks in the elastomeric block

  cracks that may be detrimental to its function-

  ment. In the variant represented in FIG. 3, the reference 9 denotes the assembly of a plate having two opposite projections 10,

  provided with holes 11 for fixing the plate 9 to the frame of a vehicle

  engine. The plate 9 has a stamped central portion 12 in the form of a frustoconical lateral surface cup. The bottom of the bowl portion 12 has a circular opening 13 traversed axially by a hollow spindle 14 in the cavity of which is

  engaged, in service, a corresponding dowel or fastener

  on the engine of a motor vehicle.

  The outer surface of the hollow spindle 14 comprises

  two end cylindrical portions 15, 16 having different diameters

  connected by a frustoconical intermediate portion 17 located in

  face of the central portion 12-shaped cup that includes the plate 9.

  Between the cup-shaped portion 12 of the plate 9 and the hollow pin 14 is interposed an annular block 18 of elastomer which is attached to the portion 12 and the block 18 by vulcanization. The elastomer block 18 is provided with two diametrically opposed openings which have the form of curved slots 19. These openings -19 are directed axially and extend over the entire height of the block 18. As in the embodiment described in FIG. Referring to Figures 1 and 2, each of the

  openings 19 has its concave surface directed towards the outside of the block 18.

  These openings 19 are furthermore formed in zones of block 18 located

  in front of the appendices 10 of the plate 9.

  The end faces of the block 18 both have profiles which, seen in section, are curved and have their convexity facing upwards. In particular, the profile of the terminal surface of the block 18 connected to the cylindrical end portion 16 of the hollow spindle 14 is shaped such that in use it is not subjected to any shear stress. This conformation, combined with the arrangement of the openings 19 described above, allows the support according to the invention to have a greater resistance to fatigue, o o a

increased longevity for this support.

  The carrier variant shown in FIG. 4 is as a whole similar to the embodiment described above with reference to FIG. 3, so that only the differences will be described in detail, the like or identical parts being marked

by the same references.

  In this variant, the openings in the block 10 in elas--

  tomère are indicated by the reference 20 and have profiles such that important parts of their contours, marked by 21, are tangential to diametrical planes A, B passing through the axis of the support. Although a more complicated embodiment than that shown in FIG. 3, this conformation allows the support to operate, under the action of forces, directed along the axis of symmetry of the block 18, in

  conitions as close as possible to uniform resistance.

  The variant shown in FIGS. 5 and 6 is also, as a whole, similar to the embodiment described above with reference to FIG. 3. Here again, in this case, the elastomer sleeve 18, the spindle hollow 14 and the cup-shaped portion 12 of the plate 9 are mutually coaxial, and the common axis is identified by HH.

  A plane passing through this axis and located between the two openings

  swam in the wings 10 of the plate 9, is identified by X-X. Two open

  Slit-shaped webs 22 are formed in the elastomer block 18 and are located symmetrically with respect to the X-X plane. Each aperture 22 in the form of a slit comprises a central portion 23 and two curved end portions 24. The intermediate portion 23 has the shape of a circular arc with its concavity turned towards the inside of the support and with its axis marked by the letter C. The two curved portions 24 of each opening 22 each have the shape of an arc of a circle, and their concavities are turned towards the outside of the support. The axes of the two curved portions 24 are marked by D. The positions of the axes D are such that the end portions 25 of each curved portion 24 are substantially parallel to the plane of symmetry X-X. In addition, the disposition of each slot-shaped aperture 22 is such that they are subdivided by the diametral plane K-K, perpendicular to the plane of symmetry X-X, into two substantially equal parts which are symmetrical

with respect to said diametrical plane.

  In the support variant shown in FIGS. 7 and 8, reference numeral 26 designates a cylindrical metal sleeve on the inner surface of which is fixed, by vulcanization, the external lateral surface of an annular block 27 made of elastomer. This block 27-elastomer has a generally cylindrical shape with end faces 28

concave to the outside.

  The inner surface of the elastomeric block is fixed by vulcanizing

  on the outer surface of a hollow cylindrical pin 29, coaxial with the sleeve 26 and having an axial dimension slightly greater than that of the sleeve 26. The hollow pin 29 is adapted to receive, in use, a corresponding member for fixing the engine

of a motor vehicle.

  As in the embodiment described above, the elastomer block 27 is provided with two diametrically opposed openings 30 in the form of curved slots whose concave surfaces are facing outwards of the block 27. In this case too the two slot-shaped openings 30 have the form of through holes

  oriented along the axis of the block 27 and having significant dimensions

  the entire length of the block itself.

  The reference 31 designates a tubular metal arm whose end is fixed by welding to the outer surface of the sleeve 26 relative to which this arm extends radially. The arm 31 has a length greater than the diameter of the sleeve 26, for example a length of about twice this diameter, and is fixed, at its opposite end, to the external surface of a cylindrical metal sleeve 32, identical to the

  sleeve 26. At the inner surface of the sleeve 32 is fixed by vulcanizing

  the outer lateral surface of an annular block 33 in glasto

  The inner surface of the block 33 is fixed vulcanically to the outer surface of a hollow cylindrical pin 34 identical to the hollow pin 29, and is adapted to receive, in use, a corresponding appendix for to establish a liaison

chassis of a motor vehicle.

  Like the block 27, the block 33 is provided with two slots 35 crossing it axially which are diametrically opposite, are curved

  and have their concave surfaces facing outward from block 33.

  As can be seen clearly in FIG. 7, the arrangement of the various elements forming the support is such that the axes of the sleeves 26 and 32, that is to say. blocks 27 and 33 made of elastomer and hollow pins 29 and 34 are arranged in a common plane Y-Y containing the longitudinal axis of the arm 31, so that the support has the general configuration of a connecting rod. The position of the slot-like openings 30 and 35 in their respective blocks 27 and 33 is such that these openings are aligned along the longitudinal axis of the arm 31 and are shared by said common plane Y-Y, each

  two substantially equal and symmetrical parts.

  In the variant shown in FIGS. 9 and 10,

  bracket mounting plate is generally referred to as the

  36 'and has, as in the case of the supports shown in Figures 1 to 6, two wings 37 provided with holes 38 to attach to the chassis of a motor vehicle. The plate 36 has a central opening in which is inserted a frustoconical sleeve 39 whose small section is connected to a cylindrical portion 40 whose

  outer surface is welded to the edge of the opening in the plate 36.

  On the inner surface of the sleeve 39 is fixed, by vulcanization, the outer surface of an annular block 41, of generally frustoconical shape, which is elastomeric. The inner surface of the sleeve 41 of elastomer is fixed, by vulcanization, to the outer surface of a sleeve 42 having a frustoconical shape complementary to that of the sleeve 39. The cavity in the sleeve 42 is arranged to receive, in use, a

  corresponding body for fixing the motor of a self-propelled

  mobile. The block 41 of elastomer has, around one of its two end faces, indicated by the reference 43, an edge 44 projecting radially outwards and bearing against a corresponding annular portion 45, directed outwards, provided on the large end of the sleeve 39. In addition, the end face 43 has a pair of peripheral stiffening ribs 46 with curved profiles, which are diametrically opposed and are opposite the wings of the

fixing 37 of the plate 36.

  The other end face of the block 41 of elastomer, designated by the reference 47, is connected to a cylindrical neck 48 having an extreme projection 49 which is radial and is fixed to the edge of the opening

central plate 36.

  The diametrically opposite slot-shaped openings in the elastomer block 41 are here each constituted by two blind holes 50, 51 which have curved profiles, are offset radially with respect to one another and which have their surfaces

  respective concaves facing outward of block 41. In particular,

  among these slot-shaped apertures, each of which

  radially outwards extends axially from the end face.

  43 of block 41 to a short distance from the other terminating face.

  Each of the two radially inwardly slotted apertures 51 extends axially over a shorter length from the end face 47 of the block 41. In addition, the radially inner slots 51 have an angular dimension. less than

  radially outer slots 50.

  In this case too, the conformation of block 41 and the arrangement

  of the slots 50 and 51 make it possible to obtain, with respect to the conventional supports, a notable increase in the resistance to

fatigue of the support.

  Although the invention has been described with reference to specific embodiments, it is understood that solutions comprising the arrangement of two curved, slot-shaped openings in the elastomer blocks of the carrier, the concave surfaces thereof. openings being turned outwards, are also applicable to elastic supports having different general shapes. Thus, for example, the connecting element, the fastening element and the elastomer block of the support could be constituted by prismatic bodies or the like, instead of bodies of revolution around

of a common axis.

  Of course, the principle of the invention remaining unchanged, the construction details and the embodiments can undergo

  important changes to what has been described and

  example, without departing from the realm of

present invention.

Claims (16)

  1. Elastic support for suspending an oscillating body on a supporting structure, in particular a motor on the chassis of a motor vehicle, comprising a hollow connection element, intended to be fixed to the supporting structure, a fixing element which is provided for the attachment of the oscillating body and is inserted into the cavity of the connecting element, and an annular intermediate block made of elastomer, having its internal surface fixed to the fixing element and its external surface fixed to the connecting element, and having two diametrically opposed curved slot-shaped openings which are axially oriented and extend the entire length of the elastomer block, which support is characterized in that each of the slot-like openings (8, 19, 20, 22, 30, 50, 51) has its concave surface directed towards   the outside of the elastomeric block (5, 18, 27, 41).   2. Support according to claim 1, characterized in that the two slot-shaped openings have the form of through holes whose straight sections are of substantially constant dimensions on   the entire length of the elastomer block.   3. Support according to one of claims 1 or 2, characterized   in that the connecting element (1) comprises a cylindrical sleeve (4) bearing, externally, two radially opposite fixing wings (2).   and in that the fastening element is constituted by a cylindrical pin   hollow nozzle (7) disposed concentrically to said cylindrical sleeve.   4. Support according to one of claims 1 or 2, characterized   in that the connecting element comprises a plate (9) having a cup-shaped central part (12) whose lateral surface is frustoconical and the bottom provided with a circular opening (13), and in that the fastening element has the form of a hollow spindle (14) having two cylindrical end portions (15, 16) which have different diameters and are connected to each other by a part frustoconical intermediate (17).   5. Support according to any one of claims 1, 2   or 4, characterized in that each of the slot-shaped apertures (20) of the elastomeric block (18) has a substantial portion (21) of its contour which is tangent to a passing plane (A, B) by the axis of the support.   6. Support according to any one of claims 1, 2   or 4, characterized in that the two slot-shaped openings (22) are arranged symmetrically with respect to a plane of symmetry (XX) of the fastening element (14) and each have two arc-shaped portions ( 24) having their concave surfaces facing outwardly of the elastomeric block (18), and a curved central portion (23) connecting these two arcuate portions (24). 7. Support according to claim 6, characterized in that at least the end portions (25) of the two arcuate portions (24) of the two slot-shaped openings extend in directions   parallel to the plane of symmetry (X-X).   8. Support according to one of claims 6 or 7, characterized   in that the central curved portion (23) of each slot-shaped aperture (22) has the shape of an arc whose concavity is turned   inwardly of the elastomer block (18).   9. Support according to any one of claims 6 to 8,   characterized in that the connecting element (9) is constituted in its central part by a sleeve-shaped part (12) and in that the latter, the fixing element (14) and the block in elastomer (18) are   constituted by bodies of revolution around a common axis (H-H).   10. Support according to claim 9, characterized in that each of the two openings (22) in the form of a slot is shared, by a   diametral plane (K-K) passing through said perpendicular common axis (H-H)   to said plane of symmetry (X-X), in two substantially equal parts   which are symmetrical with respect to said diametral plane.   11. Support according to claim 10, characterized in that the portion (12) in the form of a sleeve of the connection iliment (9) is frustoconical, and in that the fastening element (14) comprises two   end portions of cylindrical shape (15, 16) and a portion   mediate (17) of frustoconical shape.   12. Support according to one of the claims. 1 or 2, characterized   in that the fixing element for fixing the oscillating body is constituted by a hollow cylindrical pin (29), in that the connecting element comprises a cylindrical sleeve (26) concentric with said hollow pin (29) and in on the outer surface of the sleeve is rigidly fixed an end of a radial arm (31) at the other end of which is rigidly-fixed the outer surface of an identical cylindrical sleeve (32) in the cavity of which are inserted concentrically a hollow cylindrical pin (34) for connection to the carrier structure and an intermediate annular block (33) of elastomer having its inner surface 11 attached to said hollow pin (34) and its outer surface attached to said cylindrical sleeve (32) and having two slot-shaped apertures (35) which are diametrically opposed to each other and are axially oriented, these two slot-like apertures (35) extending the entire length of the elastomeric block (33). ) and having   their concave surfaces turned towards the outside of the elasto- mother (33).   13. Support according to claim 12, characterized in that the axes of the two cylindrical sleeves (26, 32) are arranged in a common plane (YY) containing the longitudinal axis of the radial arm (31), and in that the openings in the form of a slot (30, 35) of the two elastomer blocks (27, 33) are arranged so as to be shared, by said common plane (YY), each in two substantially equal parts which are   symmetrical with respect to this plane.   14. Support according to claim 1, characterized in that each slot-shaped opening comprises two blind portions (50, 51) which are radially offset and which each open in one of the   opposite end faces (43, 47) of the elastomeric block (41).   15. Support according to claim 14, characterized in that the blind portion (50) radially outer of each slot-shaped opening has dimensions greater than those of the portion radially inner (51).   16. Support according to one of claims 1 or 14, characterized   in that the connecting element (36) comprises a truncated sleeve   with two radially opposed mounting wings (37) and that the fixing piece (42) is   constituted by a sleeve having a frustoconical outer surface completed   of said sleeve (39).