Abstract:
The system of the present method, system, and device comprises a mechanism for linking components including: a rod having a widened and elastically deformable end; an axially movable needle; and a body surrounding the interacting ends of said rod and said needle; and a control device acting on said needle and capable of switching said widened elastically deformable end from an open position to a closed position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This is a national phase application under 35 U.S.C. §371 of PCT Application No. PCT/FR2009/052047, filed Oct. 26, 2009, which claims the benefit of French application Ser. No. 08/06011, filed Oct. 29, 2008, the contents of which are expressly incorporated herein by reference. 
     
    
     FIELD OF ART 
       [0002]    The present apparatus and system relate to a detachable linking system for two components or similar, intended for ensuring holding in position components one with respect to the other and subsequently authorizing, at a given time, their detachment by a relative movement generated by said system. 
       BACKGROUND 
       [0003]    The term “component” is to be understood in the broad sense thereof and can mean any element, part, device, assembly, sub-assembly, etc, able to be assembled to another identical component or not through said system of the present method, system, and device, up to a given time when it is wanted to detach them. 
         [0004]    The detachable linking system can thus find applications in a large number of technical fields. 
         [0005]    For example, in a preferred, although not exclusive, application, the system can be integrated into an ammunition including a vector, such as a missile. Indeed, it is known that some parts of the ammunition are detached one from the other upon the ignition and during the trajectory. This is more particularly the case between the base or the bottom of the ammunition and the system for accelerating or propelling the missile linked between them by specific assemblies carrying, in addition to particular equipment, the detachable linking systems being angularly distributed around an internal annular space provided between the base and the acceleration system. 
         [0006]    The usually used detachable linking systems generally comprise a linking mechanism between the two detachable components of the assembly, one being stationary, for example a plate, linked to the base, the other one movable, for example a floating support, linked to the acceleration system, and a device for controlling the linking mechanism so as to cause its motion and the detachment of the components. 
         [0007]    Such systems are currently of two types. 
         [0008]    In the first type, the linking mechanism is a ball-ended spindle, held on the movable support through screwing and having the balls radially projecting at the end of the spindle through the action of a movable central axis of the spindle, being inserted in an abutment inserted on the stationary plate. Upon the operation of the control device, being linked to the movable axis of the spindle via a ring, said axis slides with respect to the spindle and makes grooves arranged on it match with the projecting balls that retract then into the grooves and disconnect the spindle from the abutment integral with the stationary plate. The two components of the base and of the acceleration system are then released and detached one from the other. 
         [0009]    Such a system assembly prohibits any angular movement. Indeed, the drawback of an angular shift is to lose contact with all the balls, which may lead to a concentration of efforts on a restricted and too low number of balls, with, in addition, a risk of matting. Furthermore, using several balls has the drawback of only offering one single generator per ball for any contact. Furthermore, crimping the axis with the ring has is of a low dimension, thus restricting the tensile effort for decoupling. 
         [0010]    In the second type, the linking mechanism of the system is a breaking one and comprises an element to be broken under the action of the control device driving the mechanism. 
         [0011]    In a first case, the element to be broken such as an axis is arranged perpendicular to the tensile effort generated by the device and is supported at the ends thereof by a yoke fastened to the plate and in the centre thereof by a brace being fastened to the floating support and connected to the control device. Breaking occurs at two places of the axis, through shearing. 
         [0012]    In a second case, the axis to be broken is arranged parallel and coaxial to the tensile effort being connected at its ends to the plate and to the support. 
         [0013]    Breaking is due to the axis being elongated through contraction of the section. The breaking moment is hardly under control. 
         [0014]    The breaking effort, through shearing or elongation, is the major drawback of these two assemblies. Furthermore, the uncertainty of the breaking moment is detrimental to a detachment simultaneity, with a risk to cause jamming in the case of an assembly with several detachable linking systems. 
         [0015]    Moreover, it is already known from document U.S. Pat. No. 3,014,744 a detachable linking system for two components, comprising a linking mechanism for said components and a control device for said linking mechanism so as to cause said components to be detached,
       said linking mechanism being of the elastic deformation type and comprising, according to a longitudinal axis, at least:   one rod having a widened end being longitudinally slit and elastically deformable, and fastened, at its other end, to one of said components;   axially movable needle having an end being introduced in said widened end of the rod for holding it in an open position and the other end being connected to said control device; and   axial hole body, fastened to the other component and surrounding said cooperating ends of said rod and of said needle, being axially linked to the latter and comprising, within said hole, an annular axial abutment against which said widened end of said rod is applied; and   said control device being of the axial shift type, according to said longitudinal axis, and acting on said needle of the linking mechanism for moving it away from said widened end of the rod and, through the action of said abutment of the body linked to said shifted needle, for having said elastically deformable widened end switching from its open position to a closed position and enabling the relative crossing of said rod through said abutment of the body.       
 
       SUMMARY 
       [0021]    The present method, system, and device aim at remedying the drawbacks of the first mentioned systems and relates to an improvement of the detachable linking system of document U.S. Pat. No. 3,014,744 enabling, more particularly, to hold in place the different elements mutually linked, including a possible control for overcoming the manufacturing tolerances, and a detachment during the relative movement at a given selected time, with a minimum effort. 
         [0022]    To this end, the detachable linking system for two components of the last mentioned type is remarkable in that said needle is held axially in position with respect to said rod by a deformable ring carried by a component clamping member on said body and applying against an external annular edge of said needle. 
         [0023]    Thus, according to the present method, system, and device, the combination is used of the elasticity of the widened end of the rod and of the axial shift of the needle moved by the control device for, on the one hand, linking the two components and, on the other hand, detach them, without any part being broken and with a relatively low detachment effort, as a function of the elasticity of the widened end for switching from its initial open position to its closed position and anyway lower than that required for breaking the prior mechanism. The completely mechanical manufacturing reliability is also to be noticed in such a linking mechanism. 
         [0024]    Advantageously, said widened end of said rod has the shape of a longitudinally slit spherical head. And said axial abutment of the body then defines a spherical annular bearing complementary to the spherical head. 
         [0025]    Thus, a slight angular clearance is made possible, enabling to absorb manufacturing tolerances from the parts constituting the mechanism and from the associated assembly, and to facilitate the positioning of the system. The contact surface between the spherical head and the axial abutment remains identical as well in every tolerated angular position, contrarily to the ball spindle system. And the contact of the spherical head with the bearing of the abutment is then of the surface type, ensuring a better operation and positioning of the mechanism, instead of being linear according to a generator for each ball of the spindle. 
         [0026]    In a preferred embodiment, said spherical head comprises at least two slits arranged in perpendicular longitudinal planes separating said spherical head into four elastically deformable identical quarters, at the centre of which the corresponding end of said needle can be introduced so as to hold it in an initial open position. In order to achieve a much larger elasticity, said slits could extend into the rod, beyond said spherical head. 
         [0027]    In another embodiment, said widened end of said rod has a longitudinally slit conical shape. 
         [0028]    In particular, said axial abutment is arranged on an annular member mounted around said rod and inserted through screwing on said body. And fastening said rod to the corresponding component preferably occurs through screwing, the end opposed to the widened one being threaded and crossing a hole provided in said component, and a clamping nut providing the fastening of said rod. 
         [0029]    Thus, screwing the nut on the rod enables to hold the needle in place through pinching its end by the elastically deformable widened end, pressing against the engaged one of the needle. Furthermore, thanks to the threaded end of the rod, the system can be set according to the distance separating the plate and the floating support of each assembly, which distance can vary as a function of plays and defaults resulting from manufacturing and said relevant assemblies. All plays according to the axis of each system are thereby compensated and, as a result, detachment of the different linking systems provided on the assemblies will occur simultaneously. If there should be a slight tilt, the angular clearance would absorb it. 
         [0030]    Furthermore, it should be noticed that said needle is not only pinched by the elastically deformable spherical head, but it is still held axially in position with respect to said rod by the deformable ring carried by the clamping member of the component on said body and applying against an external annular edge of said needle. Thus, should vibrations or the like occur, the holding ring ensures any possible movement and prevent any inopportune unlocking at rest between the needle and the rod. 
         [0031]    Moreover, fastening said rod to the corresponding component preferably occurs through screwing, the end opposed to the widened one being threaded and crossing a hole provided in said component, and a clamping nut providing the fastening of said rod. 
         [0032]    Moreover, linking said needle to said control device preferably comprises a fastening nut receiving the threaded end of the needle opposite the one introduced in said rod, and a screw of said device. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0033]    The FIGS. of the appended drawing will better explain how the present method, system, and device can be implemented. In these FIGS., like reference numerals relate to like components 
           [0034]      FIG. 1  shows an ammunition and the different constitutive parts thereof. 
           [0035]      FIG. 2  shows, in a schematic partial perspective view, detachable linking systems of the present method, system, and device associating two components of the ammunition that are to be detached. 
           [0036]      FIGS. 3 ,  4 ,  5  and  6  are longitudinal sectional views of said linking system of the present method, system, and device according to an exemplary embodiment and shown in its different operating phases from linking of the components,  FIG. 3 , until they are completely detached,  FIG. 6 . 
           [0037]      FIGS. 3A and 5A  are enlarged cross sections of the respective open and closed positions of said elastically deformable slit spherical head, taken across the planes III-III and V-V of  FIGS. 3 and 5 . 
           [0038]      FIG. 7  is a perspective view of the elastically deformable rod of the linking mechanism. 
       
    
    
     DETAILED DESCRIPTION 
       [0039]    The ammunition M shown on  FIG. 1  usually comprises several assembled cylindrical parts (or stages), herein referred to as base or rear part  1 , tube or central part  2  and cover or front part  3 , inside which a composite C is located comprising a missile  4  (guidance system and military load not shown) linked to the acceleration and rocking system  5  and that, upon the ignition of the composite and during the flight trajectory, are to become detached. 
         [0040]    To this end, in the illustrated and enlarged embodiment of  FIG. 2 , the assembly between the base  1  and the acceleration and rocking system  5  of the composite C occurs via detachable linking systems  6  according to the present method, system, and device and being, in such an example, in the number of two. To this end, within the internal annular space  7  being available, between the base and the acceleration system, a specific assembly  8  is provided, comprising two parallel plates, the lower one  9  fastened to the base  1  via braces  10  or similar and the other upper one  11 , referred to as a floating support, connected to the acceleration system  5  through linking systems  6  of the present method, system, and device, as described hereinafter. On such assemblies, particular equipment parts  12  are provided, arranged between said plate  9  and said floating support  11  and also carried on the latter. 
         [0041]    As shown on  FIG. 3 , the shown detachable linking system  6  comprises a linking mechanism  14  between the stationary plate  9 , connected to the base, and the movable support  11 , connected to the acceleration system and, thus, to the composite C, and a control device  15  of the linking mechanism  14  for leading to the detachment of the base  1  (plate) from the acceleration system  5  (support) of the composite. Naturally, the control devices  15  associated with the assemblies  8  simultaneously act on the linking mechanisms  14  that such assemblies comprise. 
         [0042]    In the illustrated exemplary embodiment, the linking mechanism  14  comprises, along a longitudinal axis X-X parallel to the axis of the composite, an elastically deformable rod  16  connected to the plate  9 , a sliding needle  17  connected to the control device  15  and cooperating with the rod  16 , an annular cylindrical body  18  fastened to the floating support  11  and provided with an annular axial abutment member  19  for the elastically deformable rod. 
         [0043]    In particular, the rod  16  shown on  FIGS. 3 and 7  has an elastically deformable widened end  20  having, in this preferred example, the shape of a spherical head  21  with a diameter larger than that of the rod and having two through slits  22  arranged in perpendicular longitudinal planes for thereby defining four identical quarters or petals  23 . Thus, for providing some elasticity of the end  20 , the slits  22  extend into the rod  16  beyond the spherical head  21  until approximately the third, or even half, of the length of the rod, thereby forming elastically deformable spherical head elongated fingers  24 . The slits  22  arranged in the spherical head  21  allow the quarters or fingers to come closer one to the other in the direction of the axis X-X and, thus, to reduce the initial diameter of the spherical head, occupying an open position on  FIGS. 3 and 7 , with a lesser effort, as will be set forth later on. The opposite end  25  of the rod  16  has a threaded part  27  crossing a hole  28  provided in the plate and receiving a clamping nut  29  fastening the rod  16  to the plate according to the axis X-X. For holding the rod (in rotation) upon clamping the nut with a wrench or similar, the threaded part  27  ends with a cylindrical land nosepiece  26 . Of course, before being assembled to the plate, the body  18  and the abutment member  19  are arranged around the rod  16 . 
         [0044]    As to the needle  17 , it has an elongated cylindrical shape, with one end  30  being smooth and introduced through fitting into the cylindrical internal channel  31  defined by the spherical head  21  deformable elongated fingers  24  of the end of the rod  16 . The introduction distance of the smooth end  30  is substantially equal to the spherical head  21 , so that the latter is held in an initial open position, and this distance is defined by an external shoulder  33  of the smooth end  30 , axially abutting against the spherical head widened end  20  of the rod. Thus, when the smooth end  30  of the needle is inserted into the deformable spherical head  21  resting on the annular axial abutment member  19 , as seen later on, the plate  9  and the floating support  11  of the assembly  8  are locked to each other. 
         [0045]    The opposite end  32  of the needle is threaded so as to engage, through screwing, into a fastening nut  34  connecting the control device  15  to the needle  17  via a screw  35 , having its threaded rod  36  cooperating with the nut so as to abut against the threaded end  32  of the needle. Thus, the needle  17  and the screw  35  make up a whole, through the linking nut  34 . It could be furthermore noticed, on  FIG. 3 , that there is an axial play J between the control device  15  and the head  37  of the screw  35  so as to absorb some longitudinal movements due to the external environment of the assembly. 
         [0046]    The cylindrical body  18  comprises an axial hole  40  being crossed by the needle  17  and surrounding the cooperating ends, respectively with a spherical head  21  of the rod and the smooth one  30  of the needle. Such a cylindrical body  18  is centred in the floating support  11  being fastened on it, as will be seen later on, and carries, according to the axis X-X, the annular axial abutment member  19 . 
         [0047]    In particular, such an annular member  19  has its axial hole  41  extending that of the body, for the rod crossing, which hole  41  ends on the needle side with a bearing or a spherical cup  42  against which the spherical head  21  of the rod applies. Of course, the dimensions of the bearing  42  and of the head  21  match with each other. Thus, the contact between the abutment member  19  and the elastically deformable rod  16  occurs via an annular spherical surface portion authorizing for a relative angular clearance of the rod  16  connected to the plate  9  with respect to the body  18  connected to the floating support  11  in all directions like a knee hinge. It is thus understood that clamping the nut  29  of the rod  16  on the plates tends to draw the rod against the plate and thus to press the elastically deformable fingers  24  against the spherical bearing  42  and accordingly to pinch the smooth end  30  of the needle. 
         [0048]    Such an annular axial abutment member  19  is mounted through a screwing link  48  in the axial hole  40  of the body  18  and the latter has an external annular shoulder  43  forming a resting plane against which the floating support  11  applies so that the threaded end  44  of the body, coming from the annular shoulder  43  and opposite that receiving the abutment member  19 , crossing a crossing hole  45  provided in the support  11  and emerging above the latter. 
         [0049]    A retaining nut  46  is then screwed on the threaded end  44  of the body and applies via its transversal edge  47  on the support  11 , pinching it and immobilizing it against the body. 
         [0050]    Furthermore, when the systems  6  are used in severe environments for example with strong vibrations, each linking mechanism  14  could comprise a ring  50  for holding the needle  17  in axial position with respect to the rod  16  despite its smooth end  30  being pinched by the elastically deformable fingers  24 . To this end, on the needle, an external annular shoulder  51  is provided, on which the ring rests, being in turn close, on the other side, to an internal annular shoulder  52  arranged inside the retaining nut  46 . Such a ring  50  is advantageously deformable and prevents the needle  17  from axially moving back, preventing any inopportune locking before the missile is launched. 
         [0051]    As to the control device  15  of the system  6 , it moves axially and could be, for example, a driver or similar associated with the movement of the system  5 . 
         [0052]    Upon the missile being ignited, the operation of the detachable linking system according to the present method, system, and device occurs as follows. 
         [0053]    First of all, in the above mentioned application, the different linking systems  6  provided on the specific assemblies  8  connecting the base  1  to the acceleration system  5  of the missile are all in the same position and set appropriately. Namely, as shown on  FIGS. 3 and 3A , each needle  17  of the linking mechanisms  14  is implanted into the spherical head  21  in abutment against the member  19  and thereby prevents any closer shift of the spherical quarters of the head, locking mechanically the rod  16  fastened to the plate  9  to the remainder of the mechanism connected to the floating support  11  under the action of the elastic fingers  24  in an open position against the spherical bearing  42  of the annular axial abutment member  19 . The assemblies are thereby locked. 
         [0054]    As now shown on  FIG. 4 , when the control device  15  starts its axial shift or its translation according to the arrow F of the axis X-X, it first neutralizes the play J present between the latter and the head  37  of the linking screw  35  with the mechanism, that is the needle, being required for absorbing possible longitudinal axial movements, caused by the external environment. 
         [0055]    Continuing its axial shift according to the arrow F, the control device  45 , via the screw  35 , draws the needle, resulting in, on the one hand, the holding ring  50  becoming deformed which, under the action of the tensile effort caused by the axial shift of the device according to the axis X-X, retracts from the annular shoulder  52  of the nut  46  and, on the other hand, the smooth end  30  of the needle of the defined central channel  31  for the quarters  23  of the elastically deformable spherical head  21  of the rod  16  moving back. The fingers  24  always occupy their initial open position, but are no longer locked in such a position by the needle as shown on  FIG. 4 . Sliding of the needle  17  according to the arrow F continues until its external annular shoulder  51 , driving the ring  50 , becomes contacted by the latter, with the transversal bottom  53  of the retaining nut  46 . 
         [0056]    The systems  6  are then locked, as the spherical heads  21  are simply carried by the abutment members  19 , but are not detached. 
         [0057]    As a result of the control device  15  being driven, the needle  17  continues to slide according to the arrow F along the axis X-X and drives with it, via the axial link between its external annular shoulder  51  and the transversal bottom  53  of the nut, the assembly comprising the nut  46 , the floating support  11 , the cylindrical body  18  and the axial abutment member  19  being integral with each other. 
         [0058]    At that time, as shown on  FIGS. 5 and 5A , under the action of the spherical bearing  42  of the member  19  moving apart from the rod  16 , the elastically deformable fingers  24  progressively radially converge one to the other, in the direction of the axis X-X until they touch each other when the wall  54  defining the axial hole  41  of the annular abutment member  19  reaches the spherical head  22  of said rod. The latter then occupies the closed position. The detachment is then achieved. 
         [0059]    The movement of the control device continues according to the arrow F until the complete detachment represented on  FIG. 6 , between the floating support  11  carrying, in addition to the equipment  12 , the above mentioned assembly of the linking mechanism  14 , and the plate  9  on which the rod  16  is fastened, with the head thereof having elastically returned to its initial open position. 
         [0060]    As already been reported, such a detachable linking system  6  could find applications in a lot of other fields. Such dimensions and shapes could adapt to any material type requiring decoupling. Moreover, no particular maintenance (greasing, replacement, etc.) is to be provided and the reliability thereof is that of a completely mechanical system without any electrical/electronic control. Furthermore, after being positioned, it is possible to dismantle and then to assemble the system again.