Abstract:
A securing mast for securing an engine to the wing of an aircraft, wherein the device includes two fasteners, a first eng of each fastener being secured to the engine and the second end of each fastener being secured to the wing, wherein the fasteners include hinged junction means capable of modifying the geometry of the aforementioned fasteners in order to modify a distance between the engine and the wing.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the National Stage of International Application No. PCT/FR2008/050841 International Filing Date, 15 May 2008, which designated the United States of America, and which International Application was published under PCT Article 21 (s) as WO Publication No. W02008/155497 A1 and which claims priority from, and the benefit of, French Application No. 200755683 filed on 12 Jun. 2007, the disclosures of which are incorporated herein by reference in their entireties. 
     
    
     BACKGROUND 
       [0002]    The aspects of the disclosed embodiments relate to the field of aeronautics. More precisely, the disclosed embodiments relate to a securing mast equipped with two fasteners capable of connecting an engine to the wing of an aircraft at two distinct points, in other words at two different places on the engine and on the wing. The securing mast according to the disclosed embodiments is very particularly suitable for electric motors whose power supply systems for the on-board systems are electrical systems. 
         [0003]    Aircraft engines at the present time are connected to the wing of said aircraft by a rigid joint. By a rigid joint is meant a fixed mast relative to the engine and to the wing. Such a rigid securing mast requires reinforcement of the aircraft that contributes to a substantial increase in the total weight of said aircraft. Actually, during stresses from squalls, for example, the engine imposes vertical loads on the mast. To support such loads, the present securing mast is a heavy mast. 
         [0004]    In other respects, “spinning” of the engine&#39;s compressor in operation induces and propagates vibrations in the aircraft whose frequency is between 4 and 15 Hertz (Hz). “Spinning” operation, designated in general by the Anglo-Saxon term “windmilling,” occurs when the aircraft engine is stopped in flight after the breakage of one or more blades of its compressor. The compressor then rotates freely, or autorotates, under the action of a stream of air entering said engine. These induced vibrations subject the structure of the aircraft and accordingly the crew and passengers to substantial vibrational forces and among other things make it difficult for the pilot subjected to them to do his job. To resist these vibrational forces, it is known how to reinforce the structure of the aircraft and of the furnishings, supports, calculators, seats, and all of the components introduced into said aircraft, which tends to increase greatly the total weight of the aircraft. These reinforcements may increase the total weight of the aircraft by several tons. 
       SUMMARY 
       [0005]    The disclosed embodiments attempt to provide a mast for securing an engine to one of the wings of an aircraft of such a nature that it is no longer necessary to increase the weight of said aircraft in an exaggerated manner. 
         [0006]    To do this, the disclosed embodiments propose a fastener device that has two movable segments in a V-shaped arrangement. More precisely, the two segments are arranged side by side and are inclined relative to one other so that the fastener device has a V-shaped transverse cross section. By movable is meant that the connection between the aircraft and the engine made by the two segments is no longer fixed but can be modified, especially in height. Height means the dimension of the fastener device extending between the engine and the wing to which said engine is to be connected. The mobility of the fastener device according to the disclosed embodiments can be obtained by active jacks that can augment or diminish the distance between the engine and the wing as needed. For example, when the engine imposes a vertical stress on the mast, it is possible to raise said mast toward the wing to prevent or at least to reduce the stress imposed on said mast. In the same way, when the engine is in free rotation, or “windmilling,” the position of the engine relative to the wing can be modified so that said mast resists the imbalance. Imbalance means the lack of balance of the engine due to the fact that the center of gravity of said engine is not located on the axis of rotation of said engine. The mast resists the imbalance by putting itself in phase opposition relative to the vibrations induced by the autorotation of the engine. Thus it is no longer necessary to reinforce the structure of the aircraft in a general and substantial manner to resist these vibrations. 
         [0007]    The mobility of the mast according to the disclosed embodiments can be used advantageously in other respects to increase the performance of an aircraft, by providing said aircraft with an engine that has a compressor of greater diameter. Actually, the size of the engines is limited at the present time in the case of aircraft equipped with a low-mounted wing, on the one hand by keeping an eye on the ground, in other words watching the distance between the engine and the ground, which has to be great enough not to endanger the engine, and on the other hand by the distance between the engine and the wing, which also has to be great enough to avoid risks of interactions between the engine and the wing in flight. With a movable mast according to the disclosed embodiments, it is possible to reduce the distance between the engine and the wing when the aircraft is on the ground, so as to increase the clearance from the ground, and to increase the distance between the engine and the wing once the aircraft is in flight. 
         [0008]    It is also possible to use the movable mast according to the disclosed embodiments to contribute to the maneuverability and the takeoff of the aircraft by increasing the thrust of the engine as needed. For example, during takeoff it is possible to orient the output jet of the engine downward by orienting the nose of the engine toward the aircraft fuselage, and later to restore the engine to a horizontal position. In the same way it is possible to modify the position of the engine relative to the wing to orient the jet from the engine right and left laterally, to contribute to the lateral control of the flight path of the aircraft. It is thus possible to reduce the size of the aircraft&#39;s rudder, which normally provides lateral control, and thus to reduce the total weight of said aircraft. 
         [0009]    Accordingly, the subject matter of the disclosed embodiments is a securing mast intended to connect an engine to an aircraft wing, with this device having two adjacent fasteners, with a first end of each of the fasteners being integral with the engine, and with a second end of each of the fasteners being integral with the wing, characterized in that the fasteners have hinged connectors suitable for modifying a geometry of said fasteners so as to modify a distance between the engine and the wing. 
         [0010]    Hinged connectors mean connectors not fastened rigidly to the wing and to the engine, so as to permit an angular motion of the engine relative to the wing. Geometry of the fasteners means the shape, i.e. the external contour of the fasteners, their position relative to the wing, and the X, Y, Z orientation of said fasteners. Adjacent fasteners mean that they are arranged side by side so as to extend in the same transverse plane of the engine. 
         [0011]    According to the examples of embodiment of the securing mast of the disclosed embodiments, it is possible to provide for all or some of the following supplementary characteristics:
       The hinged connectors in the same fastener have two jacks, front and rear respectively, arranged in parallel with one another in a dimension of the fastener intended to extend between the engine and the wing. Such jacks provide for increasing or reducing the distance between the engine and the wing as needed.   The front jack is intended to be fastened at a first end to the engine and at the second end to the front spar of the wing, and the rear jack is intended to be fastened by a first end to the engine and by a second end to the rear spar of the wing. The two jacks thus form two opposite sides of a parallelogram whose other two sides are formed by the engine and the wing.   The hinged connectors in the same fastener have a horizontal strut connecting the ends of the two jacks fastened to the engine, thus forming a third side of the parallelogram.   The hinged connectors in the same fastener have a vertical strut connecting the, end of the front jack fastened to the front spar of the wing to the end of the rear jack fastened to the engine, so as to extend in a diagonal of the parallelogram.   The two fasteners extend in two distinct longitudinal planes inclined relative to one another, so that a distance between the first ends of the two fasteners is smaller than a distance between the second ends of said fasteners. Thus, the securing mast is V-shaped in transverse cross section.   Modification of the geometry of the fasteners is controlled by an external control system, for example depending on data from various sensors.       
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The disclosed embodiments will be better understood by reading the following description and examining the figures that accompany it. These are presented by way of example and do not limit the disclosed embodiments in any way. The figures show: 
           [0019]      FIG. 1 : a schematic view from the rear of an engine fastened to an aircraft wing by a securing mast that may be from the disclosed embodiments; 
           [0020]      FIG. 2 : a schematic side view of an engine fastened to an aircraft wing by a securing mast according to the disclosed embodiments; 
           [0021]      FIG. 3 : the mast/engine/wing assembly of  FIG. 2  viewed from the rear; 
           [0022]      FIG. 4 : a schematic side view of the mast/engine/wing assembly according to the disclosed embodiments when the engine is in a low position and in a high position; 
           [0023]      FIG. 5 : a schematic representation of two different geometries that a fastener of the securing mast according to the disclosed embodiments may have. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]      FIG. 1  shows an engine  1  fastened to the bottom face  2  of an aircraft wing  3  by a securing mast  100  that has two distinct fasteners  101 ,  102 , or segments. These fasteners  101 ,  102  provide for fastening the engine  1  to the wing  3  at two different places, specifically so as to better distribute the weight of said engine  1  on the wing  3 . More precisely, a first fastener  101  is fastened at a first end  103 , the bottom end in this case, to an upper right lateral surface  4  of the engine  1 , while a first end  104  of the second fastener  102 , also the bottom end, is fastened to an upper left lateral surface  5  of said engine  1 . In the same way, a second end, the top end  105 ,  106  in this case, of each of the fasteners  101 ,  102  of the securing mast  100  is fastened to the bottom face  2  of the wing at two distinct places. 
         [0025]    In the example shown in  FIG. 1  and in the following  FIGS. 2 ,  3 , and  4 , the fasteners  101 ,  102  are arranged relative to the engine  1  and to the wing  3  so that they have a V-shaped transverse cross section. In other words, the distance d between the bottom ends  103 ,  104  is stringently less than the distance D between the top ends  105 ,  106  of the fasteners  101 ,  102 . Such a V-shaped arrangement of the fasteners of the securing mast according to the disclosed embodiments distributes the weight of the engine over a broader surface of the wing. 
         [0026]    In all of the examples described here, the engine  1  is located beneath the lower surface  2  of the wing  3  of an aircraft. However, a wing of an aircraft can also mean a horizontal elevator of said aircraft. In this case, the engine  1  can just as well be suspended beneath the elevator as being held above said elevator. In this case, the first ends of the fasteners  101 ,  102  attaching the securing mast to the engine are the top ends, while the second ends  105 ,  106  attaching the securing mast to the wing, in this case the elevator, are the bottom ends. 
         [0027]      FIGS. 2 ,  3 , and  4  show an example of embodiment of the movable mast according to the disclosed embodiments. 
         [0028]    To be movable, each of the segments  101 ,  102  of the securing mast  100  is equipped with two jacks  107 ,  108 , each fastened to the engine  1  and to the wing  3 , and arranged one behind the other relative to the longitudinal axis A of the engine  1 . 
         [0029]    The front jack  107  is fastened at a top end  109  to the front spar  6  of the wing  3  and at a bottom end  110  to the compressor  8  of the engine  1 . The rear jack  108  is fastened at a top end  111  to the rear spar  7  of the wing  3  and at a bottom end  112  to the exhaust nozzle  9  of the engine  1 . The ends  109 ,  110 ,  111 ,  112  of the jacks  107 ,  108  are fastened to the engine  1  and the wing  3  by hinges  113 . Thus the connection between the engine  1  and the wing  3  can be modified in height H by lengthening or shortening the jacks  107 , 108  and by rotation of said jacks  107 ,  108  at the hinged connecting points  113  between said jacks  107 , 108  and the engine  1  and the wing  3 , respectively. The height H means the dimension between the longitudinal axis A of the engine  1  and the wing  3 . Front or rear means relative to the direction of flow of the air entering the engine  1  under normal conditions of use of said engine  1 . 
         [0030]    Each fastener  101 ,  102  of the securing device  100  also has a horizontal strut  114  extending between the bottom ends  110 ,  112  of the front and rear jacks  107  and  108 , respectively. The horizontal strut  114  is mounted to rotate on each of the ends  110 ,  112  of the jacks  107 ,  108  by a hinged joint  113 . 
         [0031]    Each fastener  101 ,  102  also has a vertical strut  115 . Considering that the jacks  107 ,  108  and the horizontal strut  114  form three sides of a parallelogram whose fourth side consists of the surface of the bottom face of the wing  3  extending between the two top ends  109 ,  111  of the jacks  107 ,  108 , the vertical strut  115  extends in a diagonal of said parallelogram. The jack  115  is fastened by a hinge  113  to the top end  109  of the front jack  107  and by a hinge  113  to the bottom end  112  of the rear jack  108 . The parallelogram formed by the jacks  107 ,  108  and the struts  114 ,  115  is a deformable parallelogram that can have a geometry varying from a square to a very flattened lozenge. 
         [0032]    As visible in  FIG. 4 , the geometry of the fasteners  101 ,  102  according to the disclosed embodiments is modifiable by lengthening or shortening the length of the jacks  107 ,  108 . 
         [0033]    By reducing the length of the front jacks  107  and/or increasing the length of the rear jacks  108  simultaneously in the two fasteners  101 ,  102 , the height H between the engine  1  and the wing  3  is reduced, while pushing said engine  1  forward (dashed lines in  FIG. 4 ). To move the engine  1  to the left, the length of the front jack  107  of the left fastener  102  can be increased while the length of the front jack  107  of the right fastener  101  is increased, or the length of the rear jack  108  of the left fastener  102  can be increased while the length of the rear jack of the right fastener  101  is reduced. The reverse procedure can be followed to make the engine  1  veer to the right. In this way, the distribution of the weight of the engine over the wing can be modified by conveying a greater share of the weight of said engine  1  to a right or left lateral section of said engine. This enables compensation in particular for the imbalance during “windmilling.” 
         [0034]    Of course it is possible to modify the geometry of one fastener  101 ,  102  independently of the geometry of the second fastener. 
         [0035]    In some cases, for example to compensate for imbalance, the modification of the geometry of the fasteners  101 ,  102  may advantageously be automatic, in other words without the intervention of a person present in the aircraft, for example depending on data transmitted by various sensors. In case the geometry of the fasteners  101 ,  102  is to be modified to provide for easier takeoff, or to provide for greater clearance from the ground, this modification may advantageously be controlled from the aircraft&#39;s cockpit. 
         [0036]    In a particular example of embodiment of the disclosed embodiments, and as shown in  FIG. 5 , the cover of the segments  101 ,  102  of the securing device  100  according to the disclosed embodiments is formed of independent panels  116 ,  117 ,  118 ,  119 , for example made of sheet metal or of composite material, that can slide on one another with an overlapping area between the panels to avoid aerodynamic drag. A first panel  116  has a border fastened at two points to the fixed sections of the front jack, a second panel  117  has a border fastened at two points to a left side of the horizontal strut, a third panel  118  has a border fastened at two points to a left side of the fixed section of the rear jack, a fourth panel  119  has a border fastened at two points to the wing, a fifth panel (not visible) has a border fastened at two points to a right side of the horizontal strut, and a sixth panel (not visible) has a border fastened at two points to a right side of the fixed section of the rear jack. The panels induce a deformation of the parallelogram by sliding and overlapping one another. This, in  FIG. 5 , an arrangement of the panels  116 ,  117 ,  118 ,  119  can be seen when the fastener  101 ,  102  holds the engine in a high position and when the fastener  101 ,  102  holds the engine in a low position (dashed line in  FIG. 5 ).