DIAMETER

LENGTH

WEIGHT

MATERIAL

PULL REQUIRED

COLOR

USE:

This is a pull type firing device used to initiate either booby-traps installations or de-molition charges. It is designed to operate when a direct pull is exerted on a trip wire attached to the release pin. It fires a percussion cap in a holder which can be connect-ed either to instantaneous fuse or a No. 8 detonator.

DESCRIPTION:

This switch consists of a housing tube containing a release pin, a plug, a split-head-ed striker, and a striker spring. In the cocked position, the splithead of the striker is spread over the top of the plug by the insertion of the nib on the end of the release pin. The striker is thus held under spring compression.

A safety pin is inserted through the housing tube and the release pin, preventing the latter from being desingaged from the splithead of the striker.

An anchor bracket is slipped over the housing tube to enable the switch to be an-chored in any convenient position.

A screwed collar is threaded over the open end of the tube for attachment of the cap holder.

FUNCTIONING:

A pull on the trip wire attached to the ring removes the release pin from the split-head of the striker, which then contracts and passes through the opening in the plug. The striker spring then drives the striker into the percussion cap.

INSTALLING & ARMING:

Remove the fuze adapter by unscrewing the collar. Anchor the switch by means of the bracket. Replace the collar without the fuse adapter. Install a loose trip wire, and connect the charge to the fuse adapter with detonating cord. Reset the fuse adapter on the switch by means of the collar. Withdraw the safety pin gently. With proper in-stallation, the safety pin should be loose in the safety pin hole.

DISARMING:

Insert the safety pin in the safety pin hole. Cut the trip wire and remove the fuse adapter.

REMARKS:

1. To re-use this switch, make the following test: Unscrew collar, and remove the fuse adapter. Hold the switch with open end against a piece of wood. Remove the safe-ty pin and gently pull the release pin. The striker should descend, driving its point well into the wood. The recock, push back the striker with a pencil or other wooden rod un-til the release pin slips into the splithead of the striker and locks it in place. Reinsert the safety pin.

2. To enable this switch to be used for electric firing when deisred, a special electric adapter is supplied. This consists of a small unit made of insulating material and fitted with two contact points, from which are led two lengths of rubber insulated flexible wire. The contact points are enclosed by a copper cap which is spun in position on the insulating body, and therefore cannot be removed. The unit replace the percussion cap in its holder. When the striker operates, instead of piercing the percussion cap, its dri-ven down the center portion of the copper cap so that the two enclosed contacts are short-circuited.

Visual inspection will indicate whether the copper cap has suffered accidental dama-ge. If it is dented at all the adapter should be discarded. An electric test can easily be made by connecting the adpater in series with a battery and flashlight bulb. The bulb, of course, should not light up.

To fit an electric adapter, remove the collar from the end of the switch. Remove the percussion cap holder an insert the copper-capped end of the unit inside the tube. The collar may now be threaded on the wire leads and replaced.

The adapter must be wired in series with a battery and an electric detonator. Final connection should not to be made until the switch has been installed.