Description
This is a Japanese Navy mechanical impact tail fuze. it is used in the 1 kg antipersonnel bomb. The fuze is aluminum alloy.
The fuze is integral with the tail section, and is very similar to the B-5(b) except for a reduction gear system used to slow down the arming process. The fuze is composed of the following parts: (1) Two small arming vanes held in the safe position by a drogue; (2) an arming stem; (3) gear frame containing the arming stem gear; intermediate gear, pinion gear and arming spindle gear; (4) detent retaining pin; (5) spring loaded safety detent; (6) arming spindle; (7) heavy inertia striker; (8) spring; and (9) fuze body.
Functioning
When the bomb falls free from the container, the drogue retaining the vanes is carried away by the wind, allowing the vanes to rotate. The motion of the vanes is transmitted through the reduction gear system to the spindle which is threaded out of the striker. To prevent rotation of the striker, a locating pin and keyway system are incorporated in the fuze body and striker. As the spindle rises, it also lifts the gear frame to which is secured a pin retaining the safety detent. The safety detent, which fits
through the fuze body into the striker and holds it in position, is spring-loaded outward, and removal of the safety detent pin permits it to fly out. With the spindle and detent removed, the heavy striker is held up only by a weak spring, which it overcomes on impact, initiating the gaine.
Hazardous Components
Gaine similar to Navy Type 1 with primer, detonator, booster (same as B-5(b))
Physical Data
Length, overall - 5.88 in, 149.4 mm (less booster)
Width, overall - 2.06 in, 52.3 mm
See Also
Source(s)
OP 1667, Japanese Explosive Ordnance, Volume 1 (1946)
OPNAV 30-3M, Handbook of Japanese Explosive Ordnance (1945)
TM-E9-1984, Enemy Bombs and Fuzes, Section VII, Japanese Fuzes (1942)
