(19)
(11)EP 0 455 355 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
30.11.1994 Bulletin 1994/48

(21)Application number: 91303058.1

(22)Date of filing:  08.04.1991
(51)International Patent Classification (IPC)5B64D 27/26

(54)

Engine mounting assembly

Haltevorrichtung für Triebwerke

Ensemble de montage pour moteurs


(84)Designated Contracting States:
DE FR GB IT

(30)Priority: 25.04.1990 US 514071

(43)Date of publication of application:
06.11.1991 Bulletin 1991/45

(73)Proprietor: LORD CORPORATION
Erie Pennsylvania 16514-0038 (US)

(72)Inventors:
  • Law, Thomas R.
    Edinboro, Pennsylvania 16412 (US)
  • Schmidt, Warren E.
    Erie, Pennsylvania 16505 (US)
  • Wayland, Randall S.
    Fairview, Pennsylvania 16415 (US)

(74)Representative: Dunlop, Brian Kenneth Charles et al
c/o Wynne-Jones, Lainé & James 22 Rodney Road
Cheltenham Gloucestershire GL50 1JJ
Cheltenham Gloucestershire GL50 1JJ (GB)


(56)References cited: : 
EP-A- 0 250 659
FR-A- 821 528
US-A- 4 634 081
EP-A- 0 303 405
US-A- 2 891 743
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The present invention relates to vibration isolators, and more particularly, the present invention relates to vibration isolating mounts of the type particularly suited for supporting aircraft engines.

    [0002] In certain types of jet aircraft, turbine engines are mounted to structures suspended from the aircraft wings. Generally, so-called rigid mounting bracket assemblies which do not isolate vibration have been used because space was not available for either a flexible isolator design or for the engine motion which it allowed. A feasible vibration isolating engine mount is frequently required to support lateral and vertical loads from engines weighing 4546 Kg (10,000 pounds) or more, with take-off thrust of the order of 29,326 Kg (60,000 pounds). Spring rates in the lateral and vertical directions must meet values required by dynamic vibration analyses within ±15%. Engine motion must not exceed limits such as ±0.5 cm (±.20 inches), even under loads as high as 17,287 Kg (35,000 pounds), without failure. When only one front and one rear mount are used in conjunction with the thrust links, the rear mount may be required to provide a roll spring rate of 1.135 x 10⁶ joules per radian (10,000,000 inch pounds per radian), yet still have lateral and vertical spring rates of only 122,638 nt/cm (70,000 pounds per inch). Typically, all of this must fit within a space envelope of 27.9 cm x 40.6 cm x 12.7 cm (11" x 16" x 5"). In addition to meeting these requirements, the mounting brackets must accommodate severe operating conditions, including high temperatures and vibrations.

    [0003] Various structures have been proposed for mounting turbine engines to aircraft. Examples of such structures may be found in the following U.S. Patents: 3,288,404; 3,368,270; 3,727,862; 3,831,888; 4,013,246; 4,022,018; 4,437,627; 4,603,821; and 4,603,822.

    [0004] U.S. Patent No. 3,288,404, issued to Schmidt and owned by the assignee of the present application, discloses a turbine engine mounting system which is used on a helicopter. The mounting system includes a torque tube supported in an elastomeric bearing and having arms extending therefrom for connection to an engine bracket.

    [0005] Published European Application No. 303,405 which corresponds to U.S. Patent No. 4,805,851, issued to Herbst, and owned by the assignee of the present application, discloses a turbine engine mounting system which is particularly suited for mounting turbine engines to struts suspended from the wings of jet aircraft. In this patented system, a pair of arms are connected by a torque tube which is embraced by an elastomeric bearing of a particular configuration that permits the arms to pivot about the axis of the torque tube but restricts independent pivoting to a minimum. In this way, the torque tube provides roll stiffness, i.e. reactivity to torquing of the engine about its longitudinal axis, and reactivity to torque due to lateral gusts and side loads, while supporting lateral and vertical engine loads with relatively lower spring rates. A particularly desirable feature of the Herbst mount is its ability to limit the transmission of engine vibration noise to the cabin of the aircraft.

    [0006] While the aforementioned Herbst engine mount functions satisfactorily for its intended purpose, there are aircraft engine mounting applications which require an even larger roll stiffness, greater vibration attenuation, and longer life as well as vertical and lateral load support for engines of higher thrust than those with which the Herbst mount currently finds utility. The present invention provides an engine mounting assembly which meets these requirements.

    [0007] The present invention provides a heavy duty mounting assembly which is particularly suited for use in applications which require that a variety of static and dynamic loading and motion conditions be accommodated while minimizing the transmission of noise across the mounting assembly.

    [0008] The present invention also provides a mounting assembly, suitable for an aircraft engine, which provides the required load support, which is particularly suitable for heavy duty applications.

    [0009] The present invention further provides for an aircraft turbine engine, a mounting assembly which has spring rates capable of reducing very undesirable first order engine vibrations and attenuating high frequency vibration, which together, cause noise in the aircraft cabin.

    [0010] In addition the present invention provides a mounting assembly suitable for a turbine engine, which provides enhanced stiffness to engine roll while supporting lateral and vertical loads with minimal vibration and noise transmission to the cabin of the aircraft.

    [0011] In at least some embodiments the present invention provides a unique, durable and readily manufacturable mounting assembly for mounting a high-thrust turbine engine below the wing of an aircraft while minimizing transmission of noise to the aircraft cabin.

    [0012] More specifically, the present invention provides a heavy duty mounting assembly particularly suited for isolating noise vibrations between two spaced structures, such as between the cabin of an aircraft and a high-thrust turbine engine.

    [0013] The mounting assembly includes a pair of arms disposed in spaced relation alongside one another between the two structures. Means is provided for making a torsional connection between the two arms to restrain motion relative to one another about an axis A-A extending transverse to the arms at a first location. Means is also provided for mounting the arms to one of the structures in a manner permitting the arms to pivot about axis A-A either in unison or independently of one another. Means is provided for connecting the arms to the other of the two structures at a second location spaced from said axis. The mounting assembly is characterized by a main vibration isolation connection between the arms and one of the structures being provided at a third location spaced from the pivot axis A-A whereby the structures are connected together in a manner that minimizes the transmission of vibrations between them.

    [0014] The mounting assembly is particularly suited for suspending high-thrust turbine engines below wings while minimizing engine noise transmission to the interior of the aircraft cabin.

    Brief Description of the Drawings



    [0015] The foregoing and other objects, features and advantages of the present invention should become apparent from the following description when taken in conjunction with the accompanying drawings, in which:

    Fig. 1 is a somewhat schematic side elevational view illustrating in full lines a turbine engine carried below and forward of the leading edge of a wing of an aircraft by an aft mounting bracket assembly which embodies the present invention;

    Fig. 2 is a side elevational view of the aft mounting bracket assembly attachment region indicated in Fig. 1, the view having portions partially broken away and sectioned to illustrate certain details of construction;

    Fig. 3 is a front elevational view taken on line 3-3 of Fig. 2, the view looking rearward, or aft, relative to the direction of motion of the aircraft;

    Fig. 4 is a plan view taken on line 4-4 of Fig. 3, the view looking upward at the engine mounting bracket assembly from below when installed on an aircraft;

    Fig. 5 is an exploded perspective view of the engine mounting bracket assembly of the present invention;

    Fig. 6 is an exploded perspective view of the lower portion of the assembly illustrated in Fig. 5; and

    Fig. 7 is an enlarged, partially-sectioned, transverse sectional view illustrating the manner in which the engine mounting assembly of the present invention is connected to a turbine engine hanger.


    Description of the Preferred Embodiment



    [0016] Referring now to the drawings, Fig. 1 illustrates somewhat schematically an aircraft turbine engine (E) suspended from an engine strut (S) located below an aircraft wing (W). The engine E is normally fastened to the wing structures by fore and aft engine mounting assemblies. The present invention is concerned with the aft engine mounting assembly schematically indicated within the encircled area of Fig. 1 which is denominated Fig. 2.

    [0017] As illustrated in Fig. 2, the engine mounting assembly 10 of the present invention is shown separate from the engine strut S and the engine E. The mounting assembly 10 includes a base 12 which is adapted to be fastened against the bottom surface of a suitably-shaped structural member carried on the bottom of the engine strut structure S. A pair of alignment pins 12a, 12b project upwardly from the base 12 to facilitate alignment of the base 12 during installation. The base 12 is connected to the engine strut S by high strength bolts (not shown).

    [0018] In the disclosed embodiment, the mounting assembly 10 is mounted to the aircraft in the manner illustrated in Fig. 2 with the forward direction of movement of the aircraft being indicated by the arrow denominated "fore" and the opposite, or rearward, direction being denominated by the arrow indicated "aft". As used herein, the terms "lateral" and "transverse" refer to directions perpendicular to the plane of the sheet of Fig. 2. The term "vertical" is indicated by the arrows denominated "up" and "down" running the lengthwise direction of the sheet containing Figs. 1 and 2. With reference to Fig. 7, the lateral direction is indicated by the arrows. The fore direction is perpendicular to the plane of Fig. 7, away from the viewer. In other words, Fig. 7 is a view looking forward in Fig. 1.

    [0019] As best seen in Fig. 7, the mounting assembly base means 12 is mounted intermediate the aircraft engine mounting structure S and the aircraft engine hanger (H). The hanger H has upstanding left and right lugs H₁, H₂, respectively which project upwardly into recesses R₁, R₂ respectively in the base 12. The recesses R₁, R₂ are located inward of a pair of left and right depending flanges 14 and 16, respectively, extending along opposite sides of the base 12. The hanger lugs H₁, H₂ are fastened to the mounting assembly 10 by means of transverse pin assemblies 18, 20, respectively in a manner to be described.

    [0020] The configuration of the base 12 may best be seen by reference to Fig. 5 which is an exploded perspective view looking upward toward the mounting assembly 10 as it is installed below an aircraft wing but with connecting bolts removed for purposes of clarity and with an engine attachment bracket assembly 22 displaced downwardly so that interior details of the base 12 may be viewed more readily. The base 12 includes a main generally horizontally-disposed planar plate-like portion 13 from which downturned flange means 14 and 16 depend along left and right sides respectively. The flange means, such as the left flange 14, has fore and aft surfaces 14a, 14b which confront similarly located surfaces 16a, 16b on its companion right flange 16. In the embodiment illustrated, the forward flanges 14a, 16a are spaced apart further from one another than the rearward surfaces 14b, 16b, respectively, although they need not be if spatial conditions permit.

    [0021] A pair of lugs 13a, 13b depend from the main portion 13 of the base means 12 in spaced parallel relation inward of the flanges 14 and 16, respectively. The lugs 13a, 13b have transverse aligned through bores which are in registry with through bores 14′, 16′ in the left and right flanges 14 and 16, respectively. The lugs 13a, 13b and bored flanges 14 and 16 function, as will be described, to provide a motion limiting load path for accepting overloads of other components of the mounting assembly 10.

    [0022] Various vertically-disposed holes are provided in the base 12 for receiving bolts (not shown) to enable the base 12 to be connected to the aircraft engine mounting strut S in a conventional manner. The various connecting bolts have been omitted from Fig. 5 for clarity. Preferably, the entire base 12, including the flanges 14 and 16,and the lugs 13a, 13b, is of monolithic construction, being machined from a one piece block of high-strength metal, such as Type 15-5 PH stainless steel.

    [0023] For the purpose of connecting the engine hanger H to the mounting base 12, the engine attachment bracket assembly 22 is provided. As best seen in Fig. 5, the engine attachment bracket assembly 22 fits within the confines of the base flanges 14 and 16 and is disposed closely adjacent the underside of the main plate portion 13 of the base 12. When thus assembled, the engine attachment bracket assembly 22 cooperates with the base 12 to provide a relatively low profile, compact mount configuration such as illustrated in Fig. 3. As best seen in Fig. 4, which is a view looking upward in Fig. 3, the engine hanger lugs H₁, H₂ are disposed laterally inward alongside the depending flanges 14 and 16 and laterally outward of the lugs 13a, 13b.

    [0024] The engine attachment bracket assembly indicated generally at 22 in Fig. 5 comprises several components. As best seen in Fig. 6, the attachment bracket assembly 22 includes a pair of arms 24 and 26 extending in spaced parallel relation in the fore-aft direction of the aircraft. The arms 24, 26 are torsionally interconnected at a first location by means of a torque tube 28 having a bore 28' extending along its longitudinal axis A-A. In the present instance, the first defined location is located forward of the engine hanger, but there may be installations in which it may be desirable for the location of the torque tube 28 to be aft.

    [0025] The arms 24 and 26 are interconnected at an aft location by means of a tie brace 31 extending between the arms along their upper edges. The tie brace 31 is stiff, but slightly flexible, to interconnect the arms in a manner that permits a slight amount of relative pivotal motion about the torque tube axis A-A. The arms 24 and 26 have forward extensions 24a, 26a, respectively, and the arms 24 and 26 are offset inwardly toward one another aft of the torque tube 28. Thus, the arms 24 and 26 cooperate with the torque tube 28 and the tie brace 31 to form an open, generally rectangular frame F (Fig. 6) which is disposed in substantially parallel relation with the base plate 13 (FIG. 7). The arms 24 and 26 are provided with through bores 24′, 26′ which are aligned with corresponding bores in the engine hanger lugs H₁, H₂. The bores 14′, 16′ in the flanges 14 and 16 and in the lugs 13a and 13b are enlarged to provide a vertical clearance permitting the lugs H₁, H₂ to move vertically through limited distances in the recesses R₁, R₂ when the arms 24 and 26 are connected to the engine hanger lugs H₁, H₂ by the pin assemblies 18 and 20.

    [0026] For the purpose of mounting the frame F to the base 12 in a manner permitting the frame arms 24 and 26 to pivot about the torque tube axis A-A of the torque tube 28, elastomeric bearing means is provided. As best seen in Fig. 6, the elastomeric bearing means includes a pair of upper arcuate laminated elastomeric bearing portions 40a, 42a embracing the upper side of the torque tube 28 and a diametrically opposite complementary pair of laminated elastomeric bearing portions 40b, 42b embracing the underside of the torque tube 28. The upper pair of elastomeric bearing portions 40a and 42a have elongate bosses 41, 42, respectively which are received in appropriately shaped recesses in the base plate 13. The lower pair of bearing portions 40b, 42b are similarly shaped and received by an elongate retainer 43 which extends lengthwise below the torque tube 28. Each of the bearing portions may include alternating layers of elastomeric material bonded to and between arcuate shims. The retainer 43 is fastened to the base plate 13, by fasteners, such as the pair of fasteners 45 and 46 illustrated in Fig. 3. Preferably, the fasteners 45 and 46 cooperate with spacers which are suitably dimensioned to precompress the elastomeric bearings 40a, 42a, and 40b, 42b in accordance with customary practice. Desirably, the elastomeric bearing portions are bonded to the torque tube 28 on their diametrically opposite sides so as to carry load in shear without sliding. Thus, the torque tube elastomeric bearings permit the arms 24 and 26 to pivot about the axis A-A as the engine E moves vertically when the arms 24 and 26 are connected to the engine hanger lugs H₁, H₂, respectively.

    [0027] The arms 24 and 26 are tied together by both the torque tube 28 and the tie brace 31 so that they move substantially in unison with one another as they pivot about the torque tube axis A-A. Some limited amount of independent arm deflection relative to one another is, however, accommodated by flexure of the tie brace 31. It is for this purpose that the tie brace 31 is relatively thin in the vertical direction.

    [0028] To allow arm motion required for achieving a specified vertical spring rate, and to provide additional support for the frame F, a vibration isolator means 50 is provided. As best seen in the embodiment illustrated in Fig. 6, the vibration isolator means 50 includes a main laminated elastomeric bearing pad assembly which engages the underside of the tie brace 31 and which is supported by an underlying support cap 52. The support cap 52 is secured to the plate portion 13 of the base 12 by a plurality of mounting studded spacers (not shown).

    [0029] In the present instance, the engine hanger lugs H₁, H₂ are attached to the arms 24, 26 at a location which is closer to the pivot axis A-A of the torque tube 28 than the vibration isolator pad assembly 50 although this need not occur in all applications. The unequal distances between the attachment points and the fore and aft frame bearings provide a desirable leverage action. Thus, for instance, one portion of the load carried by the frame F is transferred to the base 12 by the isolator pad 50, and another portion of the load carried by the frame F is transferred by the torque tube elastomeric bearings described heretofore. The load is thereby shared.

    [0030] The relative loading of the front and rear elastomeric assemblies provides a number of advantages. For instance, by locating the point of engine attachment between the pivot bearings and the isolator pad 50, the heavy vertical load from the engine weight is divided between these elastomeric elements, allowing all of them to be smaller in size. In previous designs, vertical load is reacted by a cocking loading of elastomer pads bonded to a shaped torque tube. In the present invention, cocking loading is eliminated. Instead, radial loads are applied to elastomeric pivot bearings, and nearly uniform, more efficient, compression loads are applied to the isolator pad. The elastomeric bearings are designed to be very stiff radially so as to be able to carry their share of vertical load without over strain. The isolator pad can be made relatively large in length and width for low compression stress, and thick for low compression strains, without compromising spring rate. The low compression stress also allows the use of a soft (low modulus) elastomer, which provides lower set and drift, less hysteresis damping, and a lower dynamic-to-static stiffness ratio. The result is increased service life, better vibration isolation, and less engine motion than other concepts having the same dynamic spring rates could provide.

    [0031] While relatively soft elastomers may be utilized in the pad 50, alternating with layers of inelastic material, such as the horizontally-disposed metal shims, the vibration isolator pad 50 may incorporate a fluid isolator which can be designed to either actively or passively provide further improved vibration isolation within a predetermined range of engine operating frequencies. Such an isolator may be designed, for example, to provide vibration and noise attenuation while the engine is operating at cruise power settings to minimize noise in the aircraft. The particular manner by which the desired vibrator isolation can be achieved is well known to designers of fluid mounts. Fluid mounts provide the advantage of enabling higher vertical and lateral static spring rates to be achieved without compromising isolation at desired operating frequencies.

    [0032] In order to control lateral motion of the frame F relative to the base 12, while permitting the aforedescribed motions of the arms 24 and 26, lateral auxiliary elastomeric pad means are provided between the frame arms and the depending base flanges 14 and 16. As best seen in Fig. 6, the lateral auxiliary pad means includes a pair of pads 30 and 32 engaging the arm extensions 24a and 26a forward of the torque tube 28 and a pair of pads 34 and 36 engaging the arm surfaces 24b and 26b adjacent the tie brace 31. Preferably the pads 30, 32, 34 and 36 are provided by laminated elastomeric bearings composed of alternating layers of elastic and inelastic materials, such layers of elastomeric material bonded to and between flat metal shims. These elastomeric bearing pads are arranged with the metal shims disposed vertically, i.e., parallel with the arm surfaces 24b and 26b and forward arm extensions 24a and 26a and perpendicular to the torque to be pivot axis A-A. As a result, the pads 30, 32, 34 and 36 are stiff in compression to control lateral motion but yieldable in shear to accommodate the required arm motions.

    [0033] Fluid mounts could also be substituted for the lateral auxiliary elastomeric bearing assemblies 30, 32, 34 and 36 to provide the aforedescribed advantages of fluid mounts in the lateral direction. Regardless of which type of lateral pad is utilized, however, it is desirable for the lateral pads 30, 32, 34 and 36 to be so located relative to the hanger lug attachment points such as to maintain the lateral elastic center of the assembly at the attachment points to reduce any lateral cocking tendency of the frame F relative to the base 12.

    [0034] In operation, downward static loads imparted to the arms 24 and 26 via the engine hanger lugs H₁, H₂ are reacted by the elastomeric forward bearing and aft pad assemblies 40, 42 and 50 in accordance with the aforedescribed load sharing relation. Vertical loading on the arms 24 and 26, caused either by steady engine weight or thrust, or by dynamic downward motion of the engine E, as on landing, or sudden upward motion, as upon encountering a downdraft, causes the arms 24 and 26 to pivot in unison about the torque tube axis A-A. Counterclockwise arm motion about the pivot bearing axis A-A (Fig. 6) causes the tie brace 31 to compress the isolator pad 50, and motion in the opposite direction relieves such compression. Extreme up or down excursion of the arms 24 and 26 is arrested, however, by engagement of the pins 18 and 20 with the bores in the lugs 13a, 13b, 14; 16. Since lateral pads 30, 32, 34 and 36, are arranged with their inelastic shims disposed vertically, they undergo shearing, thereby permitting the arms 24 and 26 to pivot with minimal constraint from the pads, permitting pad 50 to support most of the down load at that location. When reacting engine roll moment about the longitudinal axis of the engine E, the arms 24 and 26 are loaded vertically opposite one another, thereby imposing load downward on one bearing, upward on the other, and a torque about the X-X axis of the torque tube. Opposite motions of the arms 24 and 26 which are permitted by torque tube twist, is prevented from overstressing the tie brace 31 by virtue of its thinness in the vertical direction. For vertical engine motion with arms 24 and 26 moving in unison, the torsional motion of the torque tube 28 is accommodated by its associated axially-spaced elastomeric bearings due to the ability of the elastomeric layers of the bearings to undergo shearing among the inelastic layers thereof.

    [0035] By way of example, and not by way of limitation, the elastomers composing the various elastomeric bearings should be heat resistant. A preferred elastomer is type SPE® V manufactured by Lord Corporation of Erie, PA, the assignee of the present invention. The elastomeric elements used in the pivot bearings may have, and preferably have, a radial spring rate which is about 100 times as stiff as the isolator compression pad 50, but contribute less than 1% of the vertical spring rate at the hanger attachment. Other desirable characteristics of the elastomers include:
    a metallic discontinuity (low modulus) connection between engine and airframe for high frequency noise attenuation, and a very gradual change in spring rate after the onset of elastomer fatigue that allows visual "on-condition" replacement criteria. For a typical aft engine mounting load requirement of 4,546 Kg (10,000 lbs) a combined vertical spring rate of 122,638 nt/cm (70,000 lb/in) measured at the hanger attachment is desirable, 10% contributed by the forward pads and bearings, and 90% from the aft pad. Combined lateral spring rates of 122,638 nt/cm (70,000 lb/in), divided 30% fore and 70% aft are also desirable. Loss factors (tan delta) in a range of .05 to .30 are desirable for the chosen elastomers.

    [0036] In view of the foregoing, it should be apparent that the present invention now provides a turbine engine mounting assembly which is well suited for heavy duty applications and for applications requiring improved lateral and vertical vibration isolation without as much allowed engine motion as is available with known mounts. Since the mounting bracket assembly utilizes known materials and state of the art manufacturing techniques, it can be designed to meet a variety of operational requirements, yet can be assembled in a straightforward manner and refurbished readily, if necessary.

    [0037] In the disclosed embodiment, the engine strut below the wing W provides one structure and the engine hanger lugs another structure which are interconnected by means of the mounting assembly of the present invention. There may, however, be other applications in which the disclosed embodiment may find utility such as in various types of systems involving the mounting of vibratory prime movers to various types of supports. An important aspect of the disclosed embodiment is the interposition of elastomeric materials in the load path between the engine structure and its support structure to provide vibration isolation.

    [0038] In the disclosed embodiment, the arms extend in parallel relation from the torque tube, but in some applications they may converge or diverge. The ends of the arms can be interconnected by tie means, other than the metal tie brace shown, provided the requisite function is realized. The frame also need not in all instances be pivotally supported by the torque tube bearings, but could be supported pivotally at a location separated from the torque tube axis. The torque tube is, however, required. While the hanger lugs connect to the arms between the torque tube and main isolator pad, there may be applications where the arms could be extended fore or aft of either the torque tube and the main isolator pad and attachment made to the arm extensions. Accordingly, while the embodiment disclosed is the best mode contemplated by the applicants at this time, it is not to be regarded as limiting.

    [0039] Thus, while a preferred embodiment of the present invention has been described in detail, various modifications, alterations and changes may be made without departing from the scope of the invention as defined in the appended claims.


    Claims

    1. A mounting assembly (10) for use in connecting, and isolating vibration between, two spaced apart structures (S,E), including
       a pair of arms (24,26) disposed in spaced relation alongside one another between said structures (S,E),
       means (28,31) for providing a torsional connection between said arms (24,26) to restrain motion relative to one another about an axis (A-A) extending transverse to the arms (24,26) at a first location, means (12) for mounting said arms (24,26) to one (S) of said structures in a manner permitting the arms (24,26) to pivot about said axis (A-A) either in unison or independently of one another,
       means (18,20) for connecting said arms (24,26) to the other (E) of said structures at a second location spaced from said axis (A-A), said mounting assembly being characterized by
       means (50) providing a main vibration isolation connection between said arms (24,26) and said one (S) of said structures at a third location spaced from said pivot axis (A-A),
    whereby the structures (S,E) are connected together in a manner that minimizes the transmission of vibrations between them.
     
    2. A mounting assembly according to Claim 1 being further characterized by flange means (14,16) on said means (12) for mounting said arms (24,26) on said one (S) of said structures extending alongside at least portions of said arms, and auxiliary vibration isolation means (30,32,34,36) disposed between said arm portions and said flange means for restraining motion of said arms along said pivot axis (A-A) while accommodating said pivotal motion of said arms about said pivot axis.
     
    3. A mounting assembly according to Claim 2 being further characterized by said auxiliary vibration isolation means (30,34; 32,36) being disposed so that its elastic center extends through said second location.
     
    4. A mounting assembly according to Claim 2 or Claim 3 being further characterized by said flange means (14,16) extending in spaced parallel adjacent relation along opposite sides of said arms, and said auxiliary vibration isolation means including a pair (30,34; 32,36) of resilient pads disposed between each arm (24,26) and its adjacent flange means.
     
    5. A mounting assembly according to any one of Claims 1 to 4 being further characterized by said means providing said main vibration isolation connection including means (31,50,52) for resiliently connecting said arms to said one of said structures in a manner restraining substantial relative movement both between the arms and between the arms and said one structure at said third location.
     
    6. A mounting assembly according to Claim 5 being further characterized by said means for resiliently connecting said arms including a tie brace (31) connecting said arms together at said third location, a resilient compression pad assembly (50) engaging said tie brace, and cap means (52) engaging said resilient compression pad for connecting it to said one structure, whereby motion of the arms away from said one structure is reacted in compression by said resilient compression pad.
     
    7. A mounting assembly according to any of the Claims 1 to 6 being further characterized by said arms (24,26), said torsional connecting means (28) and said main vibration isolation connection (50) cooperate to form an open frame (F) disposed between said structures (S,E), and said means for mounting said arms to said one of said structures including an elastomeric bearing assembly (40a,40b,42a,42b).
     
    8. A mounting assembly according to any one of Claims 1 to 5 being further characterized by said arms (24,26) extending in spaced relation and being interconnected at said first location by a torque tube (28) which provides said torsional connection means; and said means providing said main vibration isolation connection including a tie brace (31) interconnecting said arms at said third location, a resilient compression pad (50) engaging said tie brace, and cap means (52) connecting said pad to said one of said structures (S), whereby arm motion is reacted in compression by said resilient pad.
     


    Ansprüche

    1. Haltevorrichtung (10) zum Verbinden und Schwingungsisolieren zweier beabstandeter Strukturen (S, E), mit
    einem Paar Arme (24, 26), die beabstandet und längs zueinander zwischen den Strukturen (S, E) angeordnet sind,
    Mitteln (28, 31) zum Schaffen einer Torsionsverbindung zwischen den Armen (24, 26), um eine Bewegung relativ zueinander um eine Achse (A-A) zu hemmen, die sich quer zu den Armen (24, 26) an einer ersten Stelle erstreckt, Mitteln (12) zum Befestigen der Arme (24, 26) an der einen Struktur (S) in einer Weise, daß die Arme (24, 26) um die Achse (A-A) entweder miteinander oder unabhängig voneinander schwenkbar sind,
    Mitteln (18, 20) zum Verbinden der Arme (24, 26) an der anderen Struktur (E) an einer zweiten Stelle, die von der Achse (A-A) beabstandet ist,
    gekennzeichnet durch
    Mittel (50) zur Hauptvibrationsisolationsverbindung zwischen den Armen (24, 26) und der einen Struktur (S) an einer dritten Stelle, die von der Schwenkachse (A-A) beabstandet ist,
    wobei die Strukturen (S, E) in einer Weise miteinander verbunden sind, daß die Übertragung von Schwingungen zwischen ihnen minimiert ist.
     
    2. Haltevorrichtung nach Anspruch 1, ferner gekennzeichnet durch Flanschmittel (14, 16) an den Mitteln (12) zur Befestigung der Arme (24, 26) an der einen Struktur (S), die sich längs von wenigstens Teilen der Arme erstreckt, sowie Hilfsvibrationsisolationsmittel (30, 32, 34, 36), die zwischen den Armbereichen und den Flanschmitteln angeordnet sind, um die Bewegung der Arme längs der Schwenkachse (A-A) zu hemmen, während sie die Schwenkbewegung der Arme um die Schwenkachse herum aufnehmen.
     
    3. Haltevorrichtung nach Anspruch 2, ferner gekennzeichnet durch Hilfssschwingungsisolationsmittel (30, 34; 32, 36), die derart angeordnet sind, daß sich ihre elastische Mitte durch die zweite Stelle erstreckt.
     
    4. Haltevorrichtung nach Anspruch 2 oder 3, dadurch gekennzeichnet, daß sich die Flanschmittel (14, 16) in einer beabstandeten parallelen benachbarten Beziehung entlang gegenüberliegender Seiten der Arme erstrecken, wobei die Hilfsschwingungsisolationsmittel ein Paar (30, 34; 32, 36) federnde Kissen aufweisen, die zwischen jedem Arm (24, 26) und seinen benachbarten Flanschmitteln angeordnet sind.
     
    5. Haltevorrichtung nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß die Mittel zur Hauptschwingungsisolationsverbindung Mittel (31, 50, 52) aufweisen, um die Arme mit der einen Struktur in einer Weise federnd zu verbinden, daß eine wesentliche Relativbewegung sowohl zwischen den Armen als auch zwischen den Armen und der einen Struktur an der dritten Stelle verhindert wird.
     
    6. Haltevorrichtung nach Anspruch 5, dadurch gekennzeichnet, daß die Mittel zur federnden Verbindung der Arme ein Bindeglied (31) aufweisen, das die Arme miteinander an der dritten Stelle verbindet, eine federnde Druckkissenanordnung (50), die mit dem Bindeglied in Eingriff ist, und ein Kappenmittel (52), das mit dem federnden Druckkissen in Eingriff ist, um es mit der einen Struktur zu verbinden, wobei die Bewegung der Arme, die von der einen Struktur weggerichtet ist, unter Druck von dem federnden Druckkissen aufgenommen wird.
     
    7. Haltevorrichtung nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß die Arme (24, 26), die Drehverbindungsmittel (28) und die Hauptschwingungsisolationsverbindung (50) zusammenwirken, um einen offenen Rahmen (F) zu bilden, der zwischen den Strukturen (S, E) angeordnet ist, und daß die Mittel zum Befestigen der Arme an der einen Struktur eine elastomere Lageranordnung (40a, 40b, 42a, 42b) aufweisen.
     
    8. Haltevorrichtung nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß sich die Arme (24, 26) beabstandet erstrecken und an der ersten Stelle mittels eines Drehmomentrohrs (28) verbunden sind, das die Drehverbindungsmittel schafft; und daß die Mittel für die Hauptschwingungsisolationsverbindung ein Bindeglied (31) aufweisen, das die Arme an der dritten Stelle verbindet, ein federndes Druckkissen (50), das mit dem Bindeglied in Eingriff ist, und ein Kappenmittel (52), welches das Kissen mit der einen Struktur (S) verbindet, wobei die Armbewegung unter Druck vom federnden Kissen aufgenommen ist.
     


    Revendications

    1. Ensemble de montage (10) destiné à être utilisé pour relier et isoler contre les vibrations deux structures (S, E) espacées, comprenant :

    - deux bras (24, 26) disposés en relation espacée l'un à côté de l'autre entre lesdites structures (S, E),

    - des moyens (28, 31) pour établir une liaison en torsion entre lesdits bras (24, 26), afin de les empêcher de se déplacer l'un par rapport à l'autre, autour d'un axe (A-A) s'étendant transversalement par rapport aux bras (24, 26), au niveau d'un premier emplacement, des moyens (12) pour monter lesdits bras (24, 26) sur la première (S) desdites structures, de manière à permettre aux bras (24, 26) de pivoter autour dudit axe (A-A), à l'unisson ou indépendamment l'un de l'autre,

    - des moyens (18, 20) pour relier lesdits bras (24, 26) à l'autre (E) desdites structures, au niveau d'un deuxième emplacement espacé dudit axe (A-A), ledit ensemble de montage étant caractérisé par

    - des moyens (50) établissant une liaison principale d'isolation contre les vibrations, entre lesdits bras (24, 26) et ladite première structure (S) parmi lesdites structures, au niveau d'un troisième emplacement espacé dudit axe de pivotement (A-A) ,

    les structures (S, E) étant ainsi reliées ensemble de façon à minimiser la transmission des vibrations entre elles.
     
    2. Ensemble de montage selon la revendication 1, caractérisé en outre en ce que des moyens formant rebords (14, 16) situés sur lesdits moyens (12) pour monter lesdits bras (24, 26) sur ladite première structure (S) parmi lesdites structures, s'étendent au moins le long de parties desdits bras, et des moyens auxiliaires (30, 32, 34, 36) d'isolation contre les vibrations sont disposés entre lesdites parties de bras et lesdits moyens formant rebords, afin d'empêcher un déplacement desdits bras le long dudit axe de pivotement (A-A), tout en permettant ledit mouvement de pivotement desdits bras autour dudit axe de pivotement.
     
    3. Ensemble de montage selon la revendication 2, caractérisé en outre en ce que lesdits moyens auxiliaires (30, 34; 32, 36) d'isolation contre les vibrations sont disposés de manière que leur centre élastique passe par ledit deuxième emplacement.
     
    4. Ensemble de montage selon la revendication 2 ou la revendication 3, caractérisé en outre en ce que lesdits moyens formant rebords (14, 16) s'étendent parallèlement, dans une relation adjacente, le long des côtés opposés desdits bras, et lesdits moyens auxiliaires d'isolation contre les vibrations comprennent deux tampons élastiques (30, 34; 32, 36) disposés entre chaque bras (24, 26) et le moyen formant rebord qui lui est adjacent.
     
    5. Ensemble de montage selon l'une quelconque des revendications 1 à 4, caractérisé en outre en ce que lesdits moyens établissant ladite liaison principale d'isolation contre les vibrations comprennent des moyens (31, 50, 52) pour relier élastiquement lesdits bras à ladite première structure parmi lesdites structures, de manière à empêcher un déplacement relatif important à la fois entre les bras et entre les bras et ladite première structure, au niveau dudit troisième emplacement.
     
    6. Ensemble de montage selon la revendication 5, caractérisé en outre en ce que lesdits moyens pour relier élastiquement lesdits bras comprennent un tirant (31) reliant lesdits bras ensemble au niveau dudit troisième emplacement, un ensemble formant tampon de compression élastique (50) venant au contact dudit tirant, et un moyen formant capuchon (52) venant au contact dudit tampon de compression élastique, afin de le relier à ladite première structure, un déplacement des bras à l'opposé de ladite première structure provoquant une compression dudit tampon de compression élastique.
     
    7. Ensemble de montage selon l'une quelconque des revendications 1 à 6, caractérisé en outre en ce que lesdits bras (24, 26), lesdits moyens de liaison en torsion (28) et ladite liaison principale (50) d'isolation contre les vibrations coopérent de façon à former une ossature ouverte (F) disposée entre lesdites structures (S, E), et lesdits moyens pour monter lesdits bras sur ladite première structure parmi lesdites structures comprennent un ensemble formant paliers en élastomère (40a, 40b, 42a, 42b).
     
    8. Ensemble de montage selon l'une quelconque des revendications 1 à 5, caractérisé en outre en ce que lesdits bras (24, 26) s'étendent dans une relation espacée et sont interconnectés au niveau dudit premier emplacement par un tube de couple (28) fournissant lesdits moyens de liaison en torsion; et lesdits moyens établissant ladite liaison principale d'isolation contre les vibrations comprennent un tirant (31) interconnectant lesdits bras au niveau dudit troisième emplacement, un tampon de compression élastique (50) venant au contact dudit tirant, et un moyen formant capuchon (52) reliant ledit tampon à ladite première structure parmi lesdites structures (S), un mouvement des bras provoquant une compression dudit tampon élastique.
     




    Drawing