Over-all length

Over-all diameter

Pressure or tension

Required to actuate

Mine used in

The body is covered by a screw cap through which a pressure head is free to move against a compression spring. A striker guide is held in position inside the pressure head by a firing cotter, and, in the unarmed position, by a safety pin. The lower end of this guide is positioned in the body by a guide piece. The striker guide is finished, both inter-nally and externally, to two different diameters, and a small spring is held compression between the shoulder and the underside of the pressure head.

The striker is held in position against an actuating spring by a detent ball. The upper end of this spring is held against the shoulder formed by the change in diameter of the hole through the striker guide. Inside the actuating spring is a spring which holds the small spherical-headed plunger against the safety pin. Above the safety pin is a further small plunger which holds a detent ball rigidly in position in the recess in the cotter.

Pinned to the outer end of the cotter, is a fork, resting in the groove round the pressure the pressure head, and a cotter-extractor lever, carrying a ring to which the trip-wire is attached. The lower end of the body is threaded internally to receive the cap and deto-nator holder.

With the safety pin in position, the cotter is locked in position by the plunger and the ball. At the same time, the pressure head cannot be depressed as the safety pin rests on the screw cap.

When the safety pin is removed, the plunger rises under the action of the spring. This blocks the safety pin hole and holds the plunger and the detent ball lightly against the cotter. The igniter is then armed.

1. Pressure Firing: A load of 90-100 lb. applied to the pressure head will force down the head against the spring. With the cotter still in position, the head and the striker guide will moves as one until the striker detent ball is clear of the guide piece. This ball is then free to escape and the striker can ascend onto the cap under the action of the spring.

2. Pull Firing: Under the influence of a pull on the ring, the cotter-extractor lever, which has a rocker action against the underside of the pressure head, will put out the cotter, thus freeing the striker giude from the pressure head. The spring, working between the base of the pressure head and the shoulder, will force down the guide and free the de-tent ball. The striker is freed and fires the cap.

Figure 282
Push-and-Pull Igniters