Mechanical anti-hangfire system
AssigneeHughes Helicopters, Inc.
InventorsLuis A. Bohorquez, Michael M. Cleary, Charles C. Ash, Don E. Van Osten, Robert B. Pounds, John H. Sallach
Life of this patent
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Abstract
A hangfire protection system for an externally powered gun includes a recoil sensing mechanism cooperating with a sear latching mechanism such that in the event of a hangfire, a sear engages a safety link on the chain drive assembly to keep the bolt locked. If the round fires, gun function continues; if the round does not fire there is a delay of a sufficient time to assure that the round is a dud, and it is ejected. The details of the mechanical hangfire protection system are described.
Claims20
In a gun which includes at least a feed mechanism, a gun barrel and a bolt and means to effect relative movement between the bolt and the barrel;
- and wherein the gun firing cycle includes ramming, locking the bolt, firing, unlocking the bolt, extracting, ejecting and feeding and wherein there is movement in recoil upon firing or a round, the improvement comprising:
- chain means normally continuously moving during normal gun firing to effect movement of said bolt relative to said barrel,
- means to sense recoil as an indication that a round has fired,
- stop means engageable with said chain means to stop movement of said normally continuously moving chain means to thereby stop movement of said bolt, and
- means responsive to said sensing means to control movement of said stop means between an engaged position and a disengaged position.
A gun having a hangfire protection system, comprising:
- a barrel moveable in recoil upon firing of a round, a bolt moveable toward and away from said barrel through a sequence of feeding, ramming, locking, firing, unlocking, ejecting, and extracting,
- means continuously moving during normal operation of said gun for effecting movement of said bolt in the ramming and extracting and ejecting sequence and continuously moving while said bolt is stationary during locking, firing, unlocking, and feeding
- means moveable between a first and second position and operative to stop movement of continuously moving means,
- means normally biasing said means to one of said positions during gun operation,
- latch means operative in a latched position to urge said means to one of said positions during at last ramming and bolt locking and operative in a delatched position to permit said biasing means to urge said means to the second position when a round has been fired,
- means responsive to barrel recoil to move said latch means to the unlatch position, and
- means operative in response to movement of said bolt to move said latch means to the latch position.
In an externally powered gun including a barrel, a bolt, drive means, normally moveable continuously in a predetermined path of travel and including predetermined regions at which bolt lock, firing and bolt unlock occurs, stop means operative in one position to engage said drive means to stop movement thereof and of said bolt after unlocking and before locking thereof and in a second position to permit continuous movement of said drive means, the improvement comprising a hangfire protection system including:
- (a) safety stop means moveable in the same predetermined path of travel as said drive means and so located with respect thereto that as said drive means approaches the bolt unlock region said safety stop approaches said stop means,
- (b) means normally biasing said stop means to permit passage of said drive means,
- (c) means to latch said stop means to engage said safety stop prior to bolt unlock in the event of a failure of a round to fire within a predetermined period of time,
- (d) release means operative in response to firing of a round within said predetermined period of time to unlatch said stop means to permit passage of said safety means and unlock of the bolt through movement of said drive means, and
- (e) reset means to relatch said stop means after bolt unlock and before bolt lock.
In an externally powered gun which includes a breech and barrel assembly, a bolt assembly moveable towards and away from said barrel and breech assembly, a continuously driven chain drive assembly including driving means for moving said bolt assembly, a feed assembly including a continuously driven infeed mechanism and an intermittently driven transfer mechanism to receive a round from said infeed mechanism and transfer it to said bolt assembly as the latter is in the rearward position of travel, a motor to effect movement of chain and feed assembly,
- clutch means operative to permit motor rotation when said chain and feed assembly are stopped said barrel having moveable in recoil upon firing, and wherein the gun firing cycle includes ramming, locking the bolt assembly, firing, unlocking the bolt assembly extracting and feeding, and wherein a sear mechanism, normally biased to the unsear position, is operative to engage the driving means of said chain assembly to stop movement thereof and of said feed assembly and said bolt assembly the improvement comprising:
- a hangfire protection system including
- (a) means to sense the recoil of said barrel as an indication that a round has fired,
- (b) safety means so positioned in said chain drive assembly that as said driving means is operative to unlock said bolt assembly, said safety means in engagable by said sear mechanism to stop movement of said chain drive assembly which permitting said motor to continue to rotate
- (c) latch means operative in one position to urge said sear mechanism into engagement with said safety mechanism and in another position to permit said sear mechanism to move the unsear position, and
- (d) means to reset said latch as said bolt assembly moves away from said barrel.
Dependencies are inferred from the claim text.