|
|
|
ALLIED BOMBS AND FUZES |
| PART II - U.S. BOMB FUZES |
| A. ARMY FUZES |
|
FUZE DATA |
FILE NO.: |
||
|
NATIONALY: U.S. Army |
INFORMATION DATE: Sept. 1943 |
||
|
DESIGNATION: |
M-120 |
PRINCIPLE MARKING: |
Nose Bomb |
|
|
Fuze M-120 |
||
|
CLASSIFICATION: |
Mechanical |
|
|
|
Impact Fuze |
|
||
|
|
|
BOMBS USED IN: |
M-40 parachute fragmentation bombs. |
|
|
DATA |
M-120 |
|
1 |
COLOR |
Unpainted aluminum |
|
2 |
OVERALL LENGTH |
4.4 inches. |
|
3 |
OVERALL WIDTH |
2.2 inches. |
|
4 |
MATERIAL OF CONSTRUCTION |
Aluminum alloy body, cadmium plated striker & striker head. |
|
5 |
PARTS |
|
1 |
Striker head |
7 |
Slider lug | |
|
2 |
Firing pin |
8 |
Timing shaft | |
|
3 |
Firing spring |
9 |
Sliding detonator spring | |
|
4 |
2½ sec. clockwork |
10 |
Detonator locking detent | |
|
5 |
Sliding primer detonator assembly |
11 |
Groove for locking detent | |
|
6 |
Arming pin |
12 |
Arming pin spring |
|
6 |
OPERATION |
|
|
The opening of the parachute on the M-40 fragmentation bomb withdrawn the arming wire from the arming pin (6) which is ejected by the arming pin spring (12). The ejection of the arming pin releases the semi-circular extension on the timing shaft (8) which is rotated by clockwork (4) for 180 degrees. Riding against the inside or the semi-circle under pressure of the sliding detonator spring (9) is the slider lug (7). When the extension on the timing shaft rotates its full 180 degrees, the slider lug is released allowing the spring loaded primer detonator assembly (5) to move under the firing pin (2) where it is locked in position by the detonator locking detent (10) which ri- des into groove (11). This action requires roughly 2½ seconds. On impact the striker head (1) drives the firing pin into the primer deto-nator firing the fuze. |
|
7 |
REMARKS |
|
|
This fuze with mechanical arming delay replaces the M-104 which had pyrotechnic arming delay. |
|
|
