Abstract:
A mounting arrangement ( 26 ) is provided for mounting an engine ( 10 ), typically a gas turbine engine, to a vehicle. The mounting arrangement ( 26 ) includes connecting means ( 28, 30 ) constructed to extend from a core assembly ( 14 ) of the engine ( 10 ) through an outer component ( 24 ) to the vehicle. The mounting arrangement ( 26 ) also includes transmission means ( 41 ) extending from the connecting means ( 28, 30 ) to transmit thrust from the engine ( 10 ) to the vehicle.

Description:
FIELD OF THE INVENTION 
   This invention relates to mounting arrangements for mounting an engine to a vehicle. More particularly, but not exclusively, the invention relates to mounting arrangements for mounting gas turbine engines to an aircraft. 
   BACKGROUND OF THE INVENTION 
   Arrangements for mounting gas turbine engines on aircraft are required to be such that they will minimise stresses and deflections and, such that, in doing so will enable the engine to be as light as possible. 
   SUMMARY OF THE INVENTION 
   According to one aspect of this invention, there is provided a mounting arrangement for mounting to a vehicle an engine having a core assembly and an outer component, the mounting arrangement comprising connecting means constructed to extend from the core assembly through the outer component to the vehicle, and the mounting arrangement further comprising transmission means extending from the connecting means to transmit thrust from the engine to the vehicle. 
   Preferably, the connecting means comprises a strut arrangement and attaching means, the strut arrangement being for connecting the attaching means to the core assembly, and the attaching means being for attaching the strut arrangement to the vehicle. 
   Preferably, the engine is a gas turbine engine, for example, a three shaft gas turbine engine. The outer component may be a housing surrounding the core assembly, such as a fan case or bypass duct. 
   The attaching means may comprise a shaft or may comprise pivoting means to provide said pivotal attachment. The pivoting means may comprise a ball joint. 
   The attaching means may comprise a trunion. The trunion may comprise a trunion pin. 
   The strut arrangement may comprise a frame comprising a pair of elongate connecting struts joined to each other at one end of each connecting strut to form an apex region. Said apex portion is desirably connected to the attachment means. Conveniently, the opposite end of each elongate connecting strut can be connected to a first region of the engine. 
   The transmission means may comprise support means to support the connecting means. The support means may comprise an elongate support member having first and second opposite ends. The first end of the elongate support member is preferably connected to the connecting means. Conveniently, the second end of the elongate support member is connected to a second region of the engine. The support means may be connected to the strut arrangement, conveniently in the region of the attaching means. Desirably, the support means is attached at said apex portion. 
   Preferably, the connecting means comprises an A frame. The mounting arrangement may comprise a tripod arrangement of said elongate members. 
   The outer component may define an aperture through which the connecting means can extend. In one embodiment, the attaching means may comprise an outwardly extending part of the apex portion which can extend through said aperture. In another embodiment, the attaching means may comprise a head which can be arranged in said aperture. Sealing means is preferably provided to seal the connection means to the outer component. 
   Preferably, the mounting arrangement comprises a pair of said connecting means, arrangeable in spaced relationship to each other about the engine. The connecting means may be arranged opposite each other on the engine. Preferably, the pair of connecting means are arranged at substantially diametrically opposed regions of the engine. 
   The mounting arrangement may further comprise a securing member to further secure the engine to the vehicle. The securing member may be provided rearwardly of the engine and may comprise a link member. 
   In one embodiment, the mounting arrangement may comprise carrying means to carry the outer component. The carrying means may comprise a pair of legs which may be joined to each other and to the outer component at a vertex region thereof. The carrying means may comprise a further A frame. The carrying means may be arrangeable on the engine at a region between the pair of said connection means, conveniently substantially midway therebetween. The carrying means may comprise two of said further A frames, which may be arranged opposite each other on the engine, conveniently diametrically opposite each other. Preferably, the further A frames are arranged respectively on an upper region and on a lower region of the engine. 
   According to another aspect of this invention, there is provided a gas turbine engine comprising a core assembly and an outer component, and a mounting arrangement as described above for mounting the engine to a vehicle. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An embodiment of the invention will now be described by way of example only, with reference to the accompanying drawings, in which: 
       FIG. 1  is a diagrammatic side view of a gas turbine engine; 
       FIG. 2  is a part sectional top view of the engine shown in  FIG. 1 ; 
       FIG. 3  is a view of the region marked III in  FIG. 2 ; and 
       FIG. 4  is a front schematic view of the engine shown in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIG. 1 , there is shown a three shaft gas turbine engine  10 . The engine  10  comprises a fan  12  and core assembly  14 . The fan  12  has a plurality of blades which have been omitted from the drawings for clarity. Downstream of the fan  12  in the core assembly  14  there is provided a compressor arrangement  16  comprising intermediate and high pressure compressors which successively compress the air passing through the core assembly  14 . 
   The core assembly  14  also includes a combustion arrangement  18  and a turbine arrangement  20 . The combustion arrangement  18  is provided downstream of the compressor arrangement  16  to combust the compressed air with fuel. The hot combustion products exit the combustion arrangement  18  and expand through the turbine arrangement  20 . The turbine arrangement  20  comprises a high pressure turbine, an intermediate pressure turbine and a low pressure turbine. Air passing out of the low pressure turbine is exhausted from the rear of the engine over an exhaust cone  21 . 
   The core assembly  14  also comprises a casing  22  which surrounds the compressor arrangement  16 , the combustion arrangement  18  and the turbine arrangement  20 . The casing  22  includes an intermediate casing  38  surrounding the central region of the core assembly  14 . The intermediate casing  38  is a static part of the engine  10  which, in the embodiment shown, surrounds the compressor arrangement  16  and provides structural support for other parts of the engine  10 . 
   An outer component in the form of a housing  24  for the fan  12  extends around the front region of the core  14  of the engine  10 . 
   In order to mount the engine on an aeroplane, a mounting arrangement  26  is provided which comprises a pair of connecting means  28 ,  30 . Each connecting means  28 ,  30  comprises strut arrangements in the form of an A frame  32  comprising a pair of elongate struts  34 ,  36 , one end of each of which is mounted on the intermediate casing  38 . The two elongate struts  34 ,  36  are joined together at their opposite ends to form an apex region  40 . 
   At the front of the engine  10 , there is provided a front bearing housing  42 . Transmission means, in the form of an elongate support member  41 , extends from the apex region  40  to the front bearing housing  42  of the engine  10  to form a tripod arrangement. 
   Attaching means in the form of a shaft or trunion pin  44  extends radially outwardly from the apex region  40  of each connection means  28 ,  30  through an aperture  46  in the housing  24 . The trunion pin  44  extends through a bore  45  in a ball  48 . The ball  48  is rotatably held with a race  50 , which is attached to the vehicle, a portion of which  51  is shown. Thus, rotation of the pin  44  in the bore  45  and rotation of the ball within the race  50  are permitted. The race  50  is connected directly to a pylon (shown schematically and designated  51 ) which attaches the engine to the aircraft. Sealing means  49  is provided in the aperture  46  to seal the trunion pin  44  to the housing  24 . There is negligible force transmission through the sealing means  49  to the housing  24 . The sealing means  49  is provided to prevent leakage of air through the aperture  46 . 
   The two connecting means  28 ,  30  are arranged diametrically opposite each other on the casing  22  of the core  14  at the horizontal water line of the engine  10 . 
   At the rear of the core assembly  14  of the engine  10 , there is provided a tail bearing housing  50 . Securing means in the form of a rear mount link  52  is attached to the tail bearing housing  50  to secure the rear of the engine  10  to the pylon for attaching the engine  10  to the aircraft. 
   The housing  24  is secured to the casing  22  of the core  14  of the engine  10  by fan outlet guide vanes  54  and also by carrying means in the form of a pair of A frames  56 ,  58 . The A frames  56 ,  58  comprise a pair of elongate legs  60 ,  62 , each having an end attached in spaced relation to each other to the core assembly  14  at the region of the intercase  38 . The opposite ends of the legs  60 ,  62  meet at respective vertex regions  64  which are provided at top dead centre and bottom dead centre of the housing  24 . 
   Thus, there is described a means of attaching a gas turbine engine  10  to an aircraft in which the engine  10  is mounted via the core  14  of the engine  10  through the engine housing  24  so that the engine housing  24  is not part of the connection arrangement. 
   Various modifications can be made without departing from the scope of the invention. 
   Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.