(Fig. 31)

The fuze is of the detonating type with a direct action and is used in 2-cm and 3-cm shell.

The head of the fuze is recessed at the nose to accommodate the aluminium hammer. The recess is closed against air pressure by a disc of brass foil. The hammer is in the form of a disc with a central stem which passes through a hole in the base of the recess and is aligned with the striker when the striker is in the armed position.

The aluminium striker is held in a carrier of the same material and, before arming, is dis-placed from the centre of the fuze body and the hammer. The carrier is recessed on the under side to receive the steel ball during flight.

The body is screw-threaded externally for assembly in the shell and internally to receive the magazine. Two holes to accommodate the centrifugal safety bolts are formed near its front end and a groove is formed around its exterior at this point to receive a copper retaining spring which retains the bolts in engagement with the striker carrier. A channel formed in a position displaced from the centre of the body contains the steel ball and has an extension formed along its length in which the striker is held by the two safety bolts before the fuze becomes armed. An aluminium washer, secured by stabbing, retains the ball in the channel.

On acceleration the ball is held in the base of its channel by set back. During flight the ball moves forward into the recess in the carrier as the result of deceleration and thus gives a weight bias to the recessed side of the striker carrier. Centrifugal force set up by the rotation of the projectile causes the retaining spring to expand and the safety bolts to move outwards thus freeing the striker carrier. The ball weighted end of the carrier is then moved outwards and the striker is brought into alignment with the hammer. During flight the hammer is protected from air pressure by the brass-foil closing disc and is re-tained in the forward position by creep. On impact the hammer is forced in and drives the striker into the detonator.

Fig. 31

GERMAN FUZE 1504