GB191315938A - An Improved Mechanical Time Fuse for Projectiles. - Google Patents

Abstract

15,938. Rheinische Metallwaaren und Maschinenfabrik. Aug. 6, 1912, [Convention date]. Projectile fuses.-Relates to clock-work time and percussion fuses for projectiles, and consist in mounting on the clock - work spindle a releasing - device carrying a catch which, after a set time, enters a recess in the shell-cap, thereby releasing a member which locks the firing - pin of the fuse. In the form shown in Fig. 1, the spindle 29, which is driven by clockwork, carries an arm 22, to which is pivoted on the pin d a catch 20, which is urged upwards by a spring b, but is held down by contact with the cap 38 of the shell. A pin z, Fig. 5, on the catch 20 engages a locking-ring 21, which is slotted radially to receive a pin c on the arm 22. This arm is prevented from rotating under the action of the clock-work by a pin i mounted on the end of a bolt 15 capable of sliding longitudinally in the fuse-casing. This bolt carries an arm 25, Fig. 7, engaging, before firing, a shoulder e on a rotatable member 23 having an inclined shoulder f engaging the firing-pin 3, and holding it in the cocked position. To set the fuse, the cap 38 is rotated until a recess m, into which the catch 20 is adapted to spring, is at the required angular distance from the catch. On firing, the bolt 15 sets back owing to its inertia, and (1) releases the arm 22, which is set at once in rotation by the clock-work, and (2) causes the arm 25 to slip from the shoulder e to another shoulder g on the member 23. The shoulders e, g are so placed that the bolt 15 suffers partial rotation under the action of the firing-spring 4 as the arm 25 slips from one to the other, and this causes an arm 13 on the top of the bolt to press against the locking-ring 21. When the time for which the fuse was set has elapsed, the arm 22 has rotated into position under the recess m. The catch 20 rises into this recess, disengaging the pin z from the ring 21 which is at once slidden laterally by the arm 13, the rotation of which disengages the pin 25 from the shoulder g, and leaves the member 23 free to rotate under the pressure from the spring 4 until the shoulder f is clear of the firing-pin 3, which is then impelled by its spring upon the primer 28. Should impact occur before the catch arrives opposite the recess m, the bolt 15 slides forward, releasing the member 23 and therewith the firing-pin. A stop 17, Fig. 3, limits the rotation of the arm, and takes up any reaction on the rotatable parts when the shell begins to rotate. If the cap 38 is so set that the recess m lies between the pins i and 17, time ignition is impossible. In one modification, the member 23 is dispensed with, and the shoulders e, g are formed on the bolt 15. Also, the locking-ring 21 is adapted to slide along, instead of transversely to, the spindle 29, and the catch 20 is arranged to operate centrifugally, In another modification, the releasing-pin i is replaced by a pair of pivoted catches which fly out centrifugally on firing and release a lever to start the clock-work.