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Mechanism for Setting a Fuse

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Mechanism for Setting a Fuse (19) & (11) EP 2 390 618 A1 (12) EUROPEAN PATENT APPLICATION (43) Date of publication: (51) Int Cl.: 30.11.2011 Bulletin 2011/48 F42C 17/00 (2006.01) (21) Application number: 11166830.7 (22) Date of filing: 20.05.2011 (84) Designated Contracting States: (72) Inventors: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB • Chiappini, Andrea GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO 19136, La Spezia (IT) PL PT RO RS SE SI SK SM TR • Biselli, Gianluca Designated Extension States: 19136, La Spezia (IT) BA ME (74) Representative: Di Gennaro, Sergio (30) Priority: 26.05.2010 IT TO20100439 Barzanò & Zanardo Milano S.p.A. Corso Vittorio Emanuele II, 61 (71) Applicant: Oto Melara S.p.A. 10128 Torino (IT) 19136 La Spezia (IT) (54) Mechanism for setting a fuse (57) A mechanism for setting a fuse, applied to the trol device of the position of the setting device 2, formed structure of a firearm 5, comprising a setting device 2, by a movable equipment 31 from an actuator of a vertical adapted to program such fuse, said setting device 2 being movement 34 and from an actuator of a horizontal move- fixed to a support structure 13 and comprising a reference ment 35. portion 21 and a setting portion 22, rotating around the Such actuators are able to move along a horizontal longitudinal axis of the fuse, adapted to set the fuse of a "X"-axis of the support structure, along a vertical "Z"-axis, cartridge. Such setting mechanism comprises a support the same movable equipment 31 for the positioning of structure, wherein such support structure supports a con- the setting device 2, with respect to the cartridge, kept in a predetermined position. EP 2 390 618 A1 Printed by Jouve, 75001 PARIS (FR) EP 2 390 618 A1 Description [0001] The present invention refers to a mechanism for setting fuses for ammunition. [0002] The setting device is normally a mechanic device adapted to actuate the time fuses in the ammunition. 5 [0003] The time fuses are typically placed on the frontal part of the ammunition, permitting the actuation of the explosive charge at the inside of the cartridge, by determining the burst time. [0004] More precisely, these fuses comprise two sections, a fixed one integral with the cartridge, and a movable one able to rotate with respect to the fixed one, around the axis of the ammunition; furthermore each section comprises a cavity, adapted to retain parts during the relative movement. 10 [0005] Such relative movement permits to set the time between the shooting moment of the ammunition and the moment in which the fuse causes the explosion of the charge at the inside of the cartridge, by means of a suitable inner timing mechanism. [0006] Setting devices of a completely mechanical type are known, providing a substantial encumbrance, by making such device inefficient. With the introduction of electric and electronic systems, more and more compact hybrid graduation 15 systems with better performances are developing, due to the introduction of electronic systems for actuation and control. [0007] The setting devices are normally used on ammunition used in warships such as cruisers or similar naval means needing such system, in order to program the fuses and so the burst of such ammunition. [0008] Normally the fuses produced nowadays provide a preferential axial development, with respect to the longitudinal axis of the ammunition, for the particular naval complexes on which they were installed, by occupying a great space. 20 [0009] The known method of setting the fuse essentially comprises the following steps: positioning the setting device in the vicinity of the fuse; engaging two teeth of the driving setting device in two respective cavities present on the aforementioned sections; relative rotation of the two sections mounted on the fuse. [0010] The engagement step of the driving teeth consists in two operations: identifying the reference or zero position on the fixed section of the fuse; rotation until the tooth of a lever engages with the cavity present on the movable section 25 of the fuse. [0011] The present invention aims to obviate the aforementioned problems, by realizing a hybrid setting mechanism for a fuse, adapted to be flexible, rapid and accurate. [0012] Furthermore, such mechanism is able to take different positions with respect to the position of the fuse, in order to fulfill its function also in narrow zones, as in this way the necessary maneuvering space is reduced. 30 [0013] An aspect of the present invention concerns an innovative setting mechanism for fuses, having the character- istics of the annexed claim 1. [0014] Further ancillary characteristics are contained in the dependent annexed claims. [0015] The characteristics and advantages of such setting device will be clearer and evident by the following description of an embodiment, with reference to the annexed Figures, which in particular show: 35 • Figures 1A and 1B respectively show: Figure 1A the setting mechanism according to the present invention: Figure 1B the mechanism of Figure 1A applied to a firearm; • Figure 2 shows a section on the vertical plane of the setting mechanism in Figure 1, in particular in the control device; • Figure 3 shows a section on the vertical plane of the setting device in the setting mechanism according to the present 40 invention; • Figure 4 shows an exploded view of the plurality of sledges and guides placed under the engine plate; • Figure 5 shows in particular the support structure in which the setting device is positioned; • Figure 6 shows, in a perspective view, the actuator of a vertical movement; • Figure 7 shows the actuator of a longitudinal movement in a perspective view; 45 • Figure 8 shows the actuator of a longitudinal movement and a part of the mechanism for recovering errors according to the present invention, in a top view; • Figure 9 shows the positioning of the setting device with respect to the cartridge kept in position by the mechanism for retaining cartridges. 50 With reference to the cited Figures, the setting mechanism of a fuse according to the present invention is applied to the structure of a firearm 5. Such mechanism comprises a setting device 2, fixed to a support structure 13, comprising a reference portion 21 and a setting portion 22, rotating around the longitudinal axis of the ammunition and adapted to set the fuse of the cartridge. [0016] Such mechanism comprises a support structure, supporting a control device of the position of setting device 55 2, formed by a movable equipment 31, by an actuator for vertical movement 34 and by an actuator for horizontal movement 35. [0017] Such actuators are adapted to be handled along horizontal "X"-axis of the support structure and of movable equipment 31, associated with setting device 2, along vertical "Z"- axis of the same movable equipment 31 for positioning 2 EP 2 390 618 A1 setting device 2 with respect to the cartridge, which is kept in a predetermined position by a mechanism 6 for retaining cartridges. [0018] The setting mechanism also comprises a mechanism for recovering errors, adapted to correctly position setting device 2 on "XY"-plane in the case of a non-alignment of the cartridge from its ideal axis. 5 [0019] The setting mechanism preferably takes three distinct positions, adapted to set the fuse without hindering the movement of the cartridge in the path comprised among the various steps of the loading and shooting system of the cartridges. [0020] Such positions taken by the setting mechanism are the following: 10 • a waiting position, in which such mechanism waits for the correct positioning of the cartridge and for blocking of the cartridge itself by means of a retaining mechanism of cartridges 6; • a working position, in which setting device 2 sets the fuse; • a disengaging and retracting position, in which the setting mechanism disengages the cartridge and moves away from it, by allowing the operation to the other operating steps of the naval complex. 15 [0021] Such consecutive positions permit to the setting mechanism to rapidly set the fuses of the cartridges, without interfering with the other working steps of the naval complex, even if the space in which such mechanism is positioned has reduced dimensions. [0022] In the following descriptive and not limitative embodiment of the present invention, the setting mechanism of 20 the fuse is preferably positioned in the structure of firearm 5 covered by a gun carriage 53 of the firearm, positioned under a movable shield 51 and fixed to the structure of firearm 5 by means of at least one support flange 52. [0023] The cartridge coming from a lifting system adapted to bring the cartridges in the vicinity of the firearm is positioned for setting the fuse. Such cartridge is kept in such a position from retaining mechanism 6 of the cartridges, comprising a loading arm 61, adapted to position the cartridge itself, and a plurality of lifters 62, adapted to stop the 25 cartridge in the correct position during its lifting. [0024] The support structure of the setting mechanism comprises a motor plate 11 to which at least two engines 33, preferably by screws, are fixed, adapted to rotate setting device 2, with a limit plate 12, facing and superimposed to motor plate 11, between which it moves vertically with respect to movable equipment 31. [0025] Motor plate 11 and limit plate 12 are spaced and kept in such position by a plurality of columns 14. 30 [0026] Said columns 14 are preferably metal cylindrical bars, threaded at the end and fixed to motor plate 11 and to limit plate 12 preferably by means of bolts.
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