Igniting device

Claim 1

For a multistage projectile having a longitudinal axis and a percussion igniter, the projectile being subject to forward acceleration by an initial propulsive charge and to further forward acceleration by a subsequent propulsive charge, a device for controlled ignition of the subsequent charge at a predetermined time after actuation of the initial charge, said device comprising: a firing pin which has a first end and is movably mounted with relation to the projectile for movement along said longitudinal axis between a forward position wherein the first end of the pin is in contact with the percussion igniter and a rearward position wherein the first end of the pin is rearwardly spaced from the igniter, a firing pin being movable to its second position by inertial forces thereon during acceleration of the projectile by the primary propulsive charge; resilient means urging the pin to the forward position with a force less than rearwardly directed inertial forces imposed on the resilient means by the firing pin during forward acceleration of the projectile by the primary propulsive charge, the resilient means having a portion contactable by said pin and displaceable by the inertial forces of the pin; detaining means responsive to movement of the pin to its rearward position for locking the pin in said rearward position and actuatable for releasing the pin to allow movement of the pin, by forces provided by the resilient means, to its forward position and into striking contact with the igniter; timing means actuated in response to movement of the firing pin from its forward position and toward its rearward position and operable for providing a signal at a preselected time thereafter; and a triggering means receptive and responsive to the signal provided by the timing means for actuating the detaining means, whereby the pin is released from its rearward position, travels forward and strikes the percussion igniter.