Two-purpose hook for aircraft load carriers
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to improvements in or relating to two-purpose hooks for carrying loads under aircrafts. 
     2. Description of the Prior Art 
     As a rule, loads carried by the understructure of aircrafts comprise so-called brique members, anchoring hooks or ring suspension members or loops, as disclosed in the U.S. Pat. Nos. 3,840,201 and 3,954,233. 
     SUMMARY OF THE INVENTION 
     It may happen that loads provided with one or the other suspension means have to be transported by utilizing the same releasable or jettisoning devices permanently mounted on an aircraft, and it is the essential object of this invention to provide such releasable load-carrying device which is particularly simple to manufacture and capable of carrying loads of both types by means of two-purpose hooks. 
     According to this invention, each hook equipping the load-carrying device comprises on one side a central projection capable of engaging a standard ring rigid with the load to be carried, and on the opposite side a pair of spaced lateral projections engageable in a pair of recesses formed in a bridge-like member rigid with the load to be carried. Since the jettisoning mechanism of conventional type engages only one side of the hook, it is clear that it is only necessary to so mount the above-mentioned hook on its pivot pin that it can easily be turned the other way for switching when necessary and without difficulty from the fastening of a load equipped with a ring to the fastening of of a load equipped with a bridge, and vice versa. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a vertical section illustrating the hook in side elevational view, this hook being shown while in engagement with the bridge member or like fitting rigid with a load to be jettisoned: 
     FIG. 2 is a fragmentary vertical section of the same device; 
     FIG. 3 is a perspective view showing the portion of the releasable suspension device incorporating the hook according to the invention, and 
     FIG. 4 is a perspective view of the hook of the device of FIG. 3. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1 the reference numeral 1 designates the load to be carried and jettisoned, which comprises a bridge member 2, and the reference numeral 3 designates the carrier device of which the mechanism already known per se, is not illustrated. The detachable hook member proper is shown at 4 and the shank 5 thereof, which is to remain in position, is connected through a rod 6 to said mechanism (not shown) controlling the hook movements. 
     The two members 4, 5 of the device are carried by a transverse pivot pin 7 and in the example illustrated it is assumed that the hook 4 comprises a pair of integral lateral lugs 8, 9 disposed on said pivot pin 7 on each side of the shank 5 comprising a pair of spaced depending heels 10, 11 extending over the central portion of the body of hook 4 in order to prevent any relative rotational movement between said hook 4 and its shank 5. On the inoperative side in its position shown in FIG. 1 the hook 4 carries a central projection 12 adapted to engage a load suspension ring when the hook is in the position obtained when the hook 4, considered initially in the position illustrated in FIG. 1, is removed from the pivot pin 7 and re-inserted thereon after turning said hook 4 the other way. On the opposite side, i.e. on the operative side in the position shown in FIG. 1, the hook 4 carries a pair of spaced lateral projections 13 adapted to engage the pair of corresponding recesses of bridge member 2. 
     The fixed elements of the carrier device which are necessary for a clear understanding of this invention are illustrated more in detail in FIG. 2 and comprise webs 14, 15, 16, 17 rigid with the structure of the carrier device 3 and formed with aligned holes engageable by the pivot pin 7 passing with play through a central bushing 18 rigid with the pair of central webs 15, 16 between which the hook shank 5 is rotatably mounted on said bushing 18, the lateral lugs 8, 9 of said hook 4 being rotatably mounted on the pivot pin 7 proper, that is, with one lug 8 between webs 16 and 17, and the other lug 9 between the other pair of webs 14 and 15. Furthermore, the hook shank 5 is pivotally connected to the control rod 6 by means of a pin 19. 
     The detachable pivot pin 7 comprises radial locking means in the form of bolts 20 adapted to be actuated manually by means of an internal axial push-rod 21 against the resistance of a spring, whereby the radial lock bolts 20 can be retracted by engaging an annular groove formed in said push rod for releasing the pivot pin 7, so that the latter can be removed from its bearings consisting of webs 14 to 17 for turning the hook 4 the other way whereafter the pivot pin 7 can be re-inserted in position. 
     The structure contemplated for the hook 4 and shank 5 is clearly illustrated in FIGS. 3 and 4. 
     Of course, various modifications and changes may be brought to the specific form of embodiment of the invention which is shown in the drawing and described hereinabove, without departing from the basic principles of the invention as set forth in the appended claims.