Trip Mechanisms No.4, No. 5, and No. 6 (Obsolete)

Diameter

Length

Operating load

Color

General: These devices, Trip Mechanisms Nos 4, 5, and 6, are all obsolete and are included in this publication for information only. It is not expected that they will be en-countered in optional use. Special note should be taken not to confuse these Trip Me-chanisms with the British Switches Nos. 4, 5, and 6, which are in service use.

Description

Trip Mechanism No. 4 – This device is designed on the hair-trigger principle and is in-tended to be actuated by a very light pull. It is so arranged that the pull can be taken in any direction.  A number of different trip wires can be attached to the actuating lever. With the safety clip removed, a pull on any trip wire attached to the trip lever, will pivot the lever from the top of the retaining pin, which is then forced out of the striker by its spring. The retaining balls are then allowed to move inwards, releasing the striker and firing the percussion cap, which in turn sets off the detonator and attached primer.

Trip Mechasnism No. 5 – This mechanism can be used in any of three different ways, and is provided with a light and a heavy spring which can be used alternatively to create operating conidtions of greater or less force. A setting stud is provided in a Z-shaped groove. To obtain pressure operation, place the stud in the "Press" position of the groove. Depending on the spring use, a pressure of 4 or 12 lb. will then cause the upper of two holes in the outer case to come opposite the retaining ball, allowing the retaining ball to move outward and release the striker to fire the percussion cap, detonator, and primer.

Release operation is accomplished by placing the setting stud in the "Lift" position with a weight of more than 4 or 12 lb., depending on the spring, placed on the top plate. Removal of the weight will allow the spring to force the inner casing upwards until the re-taining ball comes opposite the lower of the two holes in the outer case. The ball then moves into this hole and releases the striker.

The stud is placed in the "Press" position for pull functioning, and a trip wire is attach-ed to the central plate in such a manner that a light pull on the wire will rotate the outer case until the stud is in the "Lift" position. Since there is no weight to retain the mech-anism, the device will function immediately as for release operation, described above. A safety pin, intervening between the striker and the percussion cap, pierces the inner and outer casing.

Trip Mechansim No. 6 – This is a very simple device designated to be operated by direct pull only. It consists of a spring-loaded striker, retained by the end of a special composition wire. A pull on the wire will release the striker and fire the device. Each me-chanism is provided with two feet of this wire, wrapped around the body of the device when issued. If a longer trip wire is desired, a lenght of standard trip wire is spliced to the free end of the special wire.