FR2545205A1 - CARTRIDGE FIRE DEVICE, ASSEMBLY CONSISTING OF A CARTRIDGE AND SUCH A DEVICE AND MECHANISM INCLUDING SUCH A DEVICE OR SUCH AN ASSEMBLY - Google Patents

Abstract

A PROPELLER CARTRIDGE 12 MOUNTED IN A BODY 10, 14, 16 HAS ON ONE END TWO PRIMER-CAPSULES 34 WHICH CAN BE PUNCHED, FOR FIRE OF THE CARTRIDGE, BY SLIDING PUNCHERS 24, 24A IN THE BODY; THE PUNCHERS, NORMALLY RETAINED IN A RETRACTED POSITION BY SHEAR PINS 38, CAN BE PUSHED TOWARDS THEIR CARTRIDGE FIRE POSITIONS, AFTER PINS SHEARING, BY A COMMON FIRE PINS 40 IN A PISTON SLIDE 40 IN THE FORM OF A PISTON BORE 42 OF THE BODY LIKELY TO BE SUPPLIED WITH GAS UNDER PRESSURE.

Description

Cartridge firing device, assembly consisting

  by a cartridge and such a device, and mechanism

  cluting such a device or such an assembly.

  The present invention relates to a cartridge firing device, intended in particular, but not

  exclusively, to be used in combination with devices

  cartridge operated reils such as those used in aircraft ejection seats, parachute deployment systems and the like; the invention also relates to

  a set consisting of a cartridge and the above-mentioned

  as well as a mechanism including such

device or such an assembly.

  In this area of application, it is obvious

  It is of great importance that the cartridge successfully fires when necessary, and an object of the present invention is to provide a cartridge firing system the operation of which is

  increased reliability compared to known systems.

  To this end, the invention relates, according to a pre-

  mier aspect, a cartridge firing device com-

  taking a plurality of strikers mounted in a body to move parallel to each other between respective retracted positions and respective firing positions, each striker comprising

  an active end intended to cooperate with a capsule-

  primer and, at the opposite end, a head, the firing device comprising a common firing member mounted in the body to move parallel to the strikers and in line with them, the common firing member able to engage the striker heads to simultaneously move the strikers to their positions

firing.

  According to another aspect, the invention relates to an assembly consisting of a cartridge and a device for

  cartridge firing, characterized in that the device

  cartridge firing tif comprises a plurality of strikers mounted in a body for moving parallel to each other between respective retracted positions and respective firing positions, each striker having an active end intended

  to cooperate with a primer capsule and, at the oppo-

  a head, the assembly comprising, for each percussion

  tor, a corresponding primer capsule mounted in the

  cartridge, so that each striker, in its posi-

  retracted, has its active end spaced from the

  corresponding primer capsule, and that, when the percu-

  tor is rapidly propelled from its retracted position to its firing position, its active end strikes the corresponding primer capsule to ignite it, the assembly further comprising a firing member

  common light mounted in the body to move parallel-

  Lement to the strikers and in line with them, the common firing member being able to engage on the heads of the strikers to simultaneously move the strikers

  towards their firing positions.

  One embodiment of the invention is

  below, as an example, with reference to the

  attached sins, in which: Figure 1 is a sectional view of a cartridge and striker assembly according to the invention; Figure 2 is a view of the assembly of Figure 1 in axial section perpendicular to the section plane of Figure 1; and Figure 3 is an exploded perspective view

of all of Figures 1 and 2.

  In the drawings is shown a cartridge firing device produced in the present case in the form of a firing device for the engine of the

  rocket of an ejection seat driven by rocket for airplane.

  The assembly shown comprises a tubular cylinder head

  laire 10, a cartridge case 12 comprising a tubular cylindrical body received inside the cylinder head 10 and a head 13 received inside a generally tubular casing 14 The cartridge case 12 is of course occupied by a propellant fuel (not shown) The casing 14 is internally threaded at one end for

  receive the adjacent threaded end correspondingly

  of the tubular cylinder head 10 A striker block 16

  received inside the casing 14 has an external thread

  laughing cooperating with an internal thread formed in the casing 14, and is screwed into the casing until an end face 18 thereof opposite the cartridge case 12 comes into contact with an annular stop formed around the inside the housing 14 and turned

  to the cartridge case 12 The cylinder head 10 is sufficient

  carefully screwed into the casing 14 to block the head 13 of the cartridge case 12 between the striker block 16 and

  the adjacent end of the cylinder head 10, the head 13 comprises

  both at the junction with the cartridge body, a

  annular shoulder 22 which comes into contact with the end

  adjacent part of the tubular cylinder head 10.

  Two identical strikers 24 are mounted in

  the striker block 16 so as to slide parallel-

  ment to the common axis of the tubular cylinder head 10 and the

  ter 14, each striker 24 being substantially cylindrical and comprising a head 24 a and a tail 24 b, the head 24 a having a diameter substantially greater than that of the tail 24 b, and the tail 24 b constituting, at its end

  opposite the head, the active end of the striker desti-

  born to cooperate with a primer capsule as described below The head 24 a of each striker 24 is received

  sliding inside a corresponding cylindrical bore

  laying 25 extending into block 16 from end face 18 thereof, while tail 24 b may

  extend through a respective coaxial bore of diameter

  reduced meter extending from the end of the

  corresponding sage 25 which is opposite to the end face 18, through a face 26 of the block 15 which joins the

  head 13 of the cartridge case 12 The axes of the two

  striker strikes 24 and the bores 25 receiving these extend symmetrically with respect to the axis

  central of the cylinder head 10 and of the casing 14, in positions

  equidistant and diametrically opposite

said central axis.

  As shown in Figures 2 and 3, the head 13

  of the cartridge case 12 is hollowed out on its diametric sides

  trally opposite to define planar and parallel lateral faces 30 equidistant from the central axis of the cartridge and of the casing 14, and separated by a distance

  significantly smaller than the diameter of the cartridge case

  che and block 16, the planes of the lateral faces 30 being

  parallel to the plane common to the axes of the two strikers 24.

  Two circular recesses 32 are formed in the end face of the central part of the head 13 of the cartridge case 12 which has the lateral faces

  , being aligned, in axial direction, with the

  respective cutters 24, and receive, as shown in FIGS. 1 and 2, corresponding priming capsules 34. The end of the casing 14 closest to the

  cartridge has a slot or diametral passage comprising

  both flat side walls 17 parallel to each other and to the central axis of the housing, the slot-or passage

  comprising a bottom defined by said end face 26.

  The dimensions of the casing or passage of the casing 14 are such that the central part of the head 13 of the cartridge case is closely received inside the slit, each lateral face 30 extending all against a wall

  respective opposite parallel side 17 of the slot dia-

  metral By these means is ensured the alignment of the

  sockets 32 for primers and strikers 24.

  A central projection 36 is provided at the bottom of each recess 34 and faces the tail 24 b of the corresponding striker, the corresponding capsule-primer

  thus being, during operation, pinched between the sail-

  link 36 and the active end of the corresponding striker.

  Passages 38 extend from the bottom of each recess 32 to the hollow interior of the cartridge case to allow the hot gases generated by the ignition of

  the corresponding primer capsule to pass to the propellant

  located inside the cartridge and cartridge case

flame this one.

  Each striker 24 is normally held in a retracted position, in which its active end is spaced from the corresponding leader capsule 36 by a shear pin 38 passing through a bore of the block 16 perpendicular to the axis of the bore 25, and passing through a diametral bore of the corresponding head 24 a In this retracted position, the head 24 a of each striker 24 protrudes from the block 16 beyond

  there end face 18 thereof.

  The casing 14 supports, adjacent to the heads 24 has strikers, a piston 40 which is slidably mounted

  watertight along the axis of the casing 14 in an end portion

  mity 42 of the axial bore located inside the casing 14, the piston 40 being sealed with the bore 42 using a sealing ring 44 In the illustrated arrangement, the piston 40 has, at for the purpose of lightening, the shape of a hollow cup whose annular edge of the open end receives, when the piston 40 occupies

  its position furthest from block 16, a wall of ex-

  end 41 of the casing 14 A central passage, passing through

  the end wall 41 and in the extension of a step

  central sage 41 passing through a nozzle 50 extending through

  shot from the end wall, allows, in operation, the passage of pressurized gas for actuation of the cartridge, as described below A coding tubular pin 52 co-axial to the casing 14 and to the passage 42 is

  mounted inside the end wall and its em-

  tip 50 and protrudes into the space defined inside

  piston 40, as shown The stud 52 serves to empe-

  expensive incorrect mounting of the piston.

  In operation, the end piece 50 is connected to

  a source of compressed gas, which can for example be pro-

  duit by another cartridge device (not shown), which causes the piston 40 to push against the ends of the heads 24 has strikers The shear pins 38 hold the strikers 24 in the retracted position until the pressure of the gas which forces the piston 40 against the strikers to have reached a sufficient value

  to break the shear pins 38, the percussions

  teurs 24 then being rapidly propelled forward to strike the primers 34 and thus put to

fire the cartridge.

  It will be noted that, since the strikers and the primers are duplicated, the risk that these two sets of elements simultaneously operate

  incorrect, and thus fail to ignite the car-

  key, is significantly less than what would exist if a single striker and primer capsule assembly were

  In addition, the structure shown in the

  sins makes it possible to use strikers with a slightly lighter structure and a diameter a little smaller than those conventionally used, which in turn makes the assembly less subject than in the past to untimely actuation when is subjected to a very high acceleration, for example during a bursting of the cylinder head 10

  or of the casing 14 or of an impact on the airplane equipped with the

  At the same time, the piston structure described per-

  puts the piston 40 to be very light, and the lightness of the pis-

  tone can be favored by an appropriate choice of the material thereof, such as titanium, to further minimize the risk of inadvertent ignition of the cartridge to

  because of a substantial acceleration exerted on the

  Nevertheless, the piston device described has a large surface, to be sensitive to gas pressures of limited value, which also makes the pins

more efficient shear.

Claims (7)

  1 Cartridge firing device, charac-   terized in that it comprises a plurality of strikers   (24) mounted in a body (16) to move parallel-   lying to each other between respective retracted positions and respective firing positions, each striker having an active end (24 b) intended to cooperate with a primer capsule (34) and, at the opposite end, a head (24a), the firing device comprising a common firing member (40) mounted in the body (14) for moving parallel to the strikers (24) and in line with them, the firing member common fire (40) which can engage on the heads (24 a) of the strikers to simultaneously move the   strikers towards their firing positions.   2 cartridge firing device according to claim 1, characterized in that the triggering member   common fire includes a piston (40) movable in a bore   sage (42) under the action of a gas pressure.   3 Cartridge firing device according to claim 2, characterized in that each striker   (24) associated with a shear pin   respective (38), which retains the striker in its retracted position.   4 Mechanism, characterized in that it comprises   a cartridge firing device according to one conch of claims 1 to 3.   Assembly consisting of a cartridge and a cartridge firing device, characterized in that the cartridge firing device comprises a plurality of strikers (24) mounted in a body (16) for moving parallel to each other between respective retracted positions and respective firing positions, each striker having an active end (24 b) intended to cooperate with a primer capsule (34) and, at the opposite end, a head (24 a) , the assembly comprising, for each striker (24), a corresponding primer capsule (34) mounted in the cartridge (12), so that each striker (24), in its retracted position, has its active end spaced from the corresponding primer capsule, and that,   when the striker is rapidly propelled from its position   tion retracted to its firing position, its   active mite hits the corresponding primer capsule (34) to ignite it, the assembly further comprising a   common firing member (40) mounted in the body (14) -   to move parallel to the strikers (24) and in line with them, the common firing member (40) being able to engage on the heads (24a) of the strikers to simultaneously move the strikers towards their setting positions fire.   6 An assembly according to claim 5, character-   laughed in that the common firing member comprises a piston (40) movable in a bore (42) under the action gas pressure.   7 assembly according to claim 6, character-   laughed in that each striker (24) has associated with it a respective shear pin (38),   which retains the striker in its retracted position.   8 Mechanism, characterized in that it comprises   an assembly according to any one of claims 5 to 7.