Description
The depth adjuster comprises a cylindrical body in which is housed an orifice plate containing three leak holes of different sizes, corresponding to firing depths of 50, 100, and 150 feet. Located on top of the orifice plate are a strainer plate and an adjuster spring, which holds the strainer plate in position and the orifice plate on its seating. The orifice plate is mounted on a spindle, the lower end of which fits in a hole in the bottom of the adjuster body and is hollow and slotted to receive a safety rod. Fitted loosely on the upper end of the spindle is a spring barrel, an extension of which fits in a hole in the center of an adjuster cover. A pointer is secured to the spring-barrel extension, and both extension and pointer are slotted for the use of a winding tool. A pin in the bottom of the spring barrel projects through the strainer plate into a hole in the orifice plate. Coupled to the bottom of the spring barrel at its lower end, and to the adjuster cover at its upper end, is a torsion spring, which tends to rotate the orifice plate and the pointer in a clockwise direction.
The adjuster body is closed by the adjuster cover. Marked on the cover is the word SAFE, and the depth setting numbers 50, 100, and 150. At the side of the word SAFE is a hole to receive the safety stud, and beside each number, a hole for a stop pin. Three inlet holes in the cover allow water to enter the adjuster body. In the safe position the pointer is secured to the safety stud by a safety clip.
In the bottom of the adjuster body is a hole which allows water to enter the primer tube of a depth charge, when any particular leak hole in the orifice plate is in line with it. but it is blanked by a plain section of the orifice plate when the depth adjuster is set at safe.
Screwed to a spigot on the bottom of the adjuster body is a safety-rod guide to which is screwed the upper end of the distance tube. This tube houses a safety rod, through the upper end of which is inserted a pin which engages in the slots in the orifice plate spindle and also with two cams formed on the spigot on the bottom of the adjuster body. When the depth adjuster is set on SAFE, the safety rod is held in the lowered position.
The pistol comprises a cylindrical body which houses a firing mechanism. The body is closed at the upper end by a pistol cover, which is screwed to the lower end of the distance tube and is secured in the pistol body by a ring nut. In the pistol cover and the pistol body, respectively, slide an inner and outer flanged sleeve, each sleeve having a hollow stem, the stem of the outer sleeve sliding over that of the inner. Between the flanges of the sleeves is a double acting rubber diaphragm, the two discs of which are separated by a distance ring. Between each disc of the diaphragm and the distance ring is a lead-foil washer to prevent adhesion. The pistol cover, pistol body, and sleeves have air vents to equalize the internal pressure. The pistol body and distance ring both have six evenly spaced holes through which is transmitted the pressure which expands the diaphragm, thereby moving the sleeves in opposite directions. The fact that the inner and outer sleeves move in opposite directions to operate the firing mechanism renders the pistol inertia proof, as no shock can produce these opposed motions simultaneously. The striker slides in the stem of the inner sleeve and is held cocked by two balls, located in the inner sleeve, engaging in a groove in the striker. When the depth adjusted is set on SAFE, the striker is prevented from moving upwards by the safety rod.
Some Depth-Charge Pistols Mk X** have an adjuster with holes drilled for 250. 350, and 500 feet. This pistol, though no longer used for aircraft depth charges, remains the standard depth charge pistol for charges dropped by surface craft. An identical copy of this pistol has been developed and used by the Japanese.
Functioning
No information about functioning.
See Also
Nothing else to see.
Source(s)
OP 1665, British Explosive Ordnance (1946)
