Abstract A delay arming fuze for a fin stabilized mortar round or rocket for the prevention of premature arming of the fuze while the round is in the mortar tube. The fuze consists of a fuze head which has axial bores, a spring biased striker carrying a firing pin slidable in the bores, a radially slotted adapter carried by the striker and a plurality of steel balls which, when the round is in a mortar tube assume a position rearward of the adapter to maintain the fuze unarmed. When the round is fired acceleration forces hold the balls in their rearward position until the round decelerates, at which time the balls under inertial forces roll forward through the radial slots in a metered manner to the forward side of the adapter to arm the fuze and to thereby permit firing upon target impact. The metering effect is produced by providing more balls than there are radial slots in the adapter so that all of the balls cannot enter the slots at the same moment. Relative movement between the round and the balls which are subjected to the same gravitational forces is due to the fact that the round is subjected to frictional resistance of the atmosphere through which it passes and therefore decelerates more rapidly than the balls which are not subjected to such resistance.
Inventors
👤 O Bruno
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-07 20:48
CPC Classifications
F; F42; F42C; F42C14/00; F42C15/00; F42C15/24
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
207 words
A delayed arming mechanism for a fin stabilized round fuze including a head having a series of axially aligned bores therethrough, comprising a detonating striker slidably mounted in the outermost bore of the head, a block carried by the striker for movement therewith within such outermost bore, resilient means within the head to bias the striker and block in a forward direction, to provide a chamber in one of the bores behind the block to receive the balls, there being a series of independent slots extending longitudinally completely through said block, and a plurality of balls of greater number than there are slots in the block, said balls each having a diameter less than the effective diameter of each slot, but substantially greater than half such effective diameter of the slot so that they will roll through the slots in a metered manner whereby when said fuze is in an upright position said balls will roll through said slots to an operative position inward of the block to prevent inward movement of the detonating striker, and when said fuze is decelerated in flight the balls will roll through said slots to an inoperative position forward of the block to thereby place the fuze in an armed condition.
Claim 2
Dependent Claim
207 words
A delayed arming mechanism for a fin stabilized round fuze including a head having a series of axially aligned bores therethrough, comprising a detonating striker slidably mounted in the outermost bore of the head, a block carried by the striker for movement therewith within such outermost bore, resilient means within the head to bias the striker and block in a forward direction, to provide a chamber in one of the bores behind the block to receive the balls, there being a series of independent slots extending longitudinally completely through said block, and a plurality of balls of greater number than there are slots in the block, said balls each having a diameter less than the effective diameter of each slot, but substantially greater than half such effective diameter of the slot so that they will roll through the slots in a metered manner whereby when said fuze is in an upright position said balls will roll through said slots to an operative position inward of the block to prevent inward movement of the detonating striker, and when said fuze is decelerated in flight the balls will roll through said slots to an inoperative position forward of the block to thereby place the fuze in an armed condition.
Claim 3
Dependent Claim
126 words
The device of claim 1 in which the block is of cylindrical configuration of a size to snugly fit within the outermost bore of the head, a hollow cup carried by the outer end of the striker and engaging the outer end of the block to form a chamber for reception of the balls which pass forwardly through the block during deceleration of the fuze, the forwardly biased striker normally being held in a position in which the rearward end of the block is spaced above the rearward end of the outermost bore a distance substantially greater than the diameter of each ball so as to provide a chamber for the reception of the balls behind the block during the unarmed safety position of the fuze.