A tilt fuze or fuse is a device usually used in the operation of car bombs and other such detonators, relying on the force of a jerk or similar movement for the triggering of the desired explosion.
The tilt fuze is typically a home-made mercury switch. It consists of a small tube no larger than a medical tablet bottle, made from plastic, glass or some other such material.At the bottom end of the tube, a certain volume of mercury is placed, while at the cap end are wired two live electrical contacts linked to a battery and bomb. This apparatus is then fixed lengthwise to the target vehicle; most usually, the tube is attached to the underside, below the driver or passenger's seat (depending on the desired target and the strength and quantity of the detonators) or within the mudguards.
The function of the fuze is such that when it is tilted or moved, the mercury – a liquid metal – will slide down the tube and close the electrical circuit wired to the bomb. Once the circuit is closed, the electric current will then be able to bridge the previously open gap and activate the bomb presumably concealed in another part of the vehicle. Such a tilting of the tilt fuze will likely occur over the regular bumps and jerks of the vehicle driving, ascension up the slope of a hill, or the depression of the brake or acceleration pedals, depending on the placement of the tube.
Due to the volatility in the conduction of the operation, bombers often take precautionary measures to prevent accidental tilting of the fuze while they are setting up. These often include a timer incorporated with the electric current; the bomber may set a certain time period before the contacts become live, therefore ensuring that the bomb cannot be activated until the bomber is well clear of the area.
Tilt fuzes sometimes meet use with the anti-handling devices incorporated into munitions such as the VS-50 mine. The Luftwaffe in World War II are known to have made use of variants of the tilt fuze in their bomb fuzes. Tilt fuzes have been used extensively by the Irish Republican Army and Irish National Liberation Army since 1979.
A relay is an electrically operated switch. It consists of a set of input terminals for a single or multiple control signals, and a set of operating contact terminals. The switch may have any number of contacts in multiple contact forms, such as make contacts, break contacts, or combinations thereof.
In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type of switch is an electromechanical device consisting of one or more sets of movable electrical contacts connected to external circuits. When a pair of contacts is touching current can pass between them, while when the contacts are separated no current can flow.
A detonator, sometimes called a blasting cap in the US, is a small sensitive device used to provoke a larger, more powerful but relatively insensitive secondary explosive of an explosive device used in commercial mining, excavation, demolition, etc.
A car bomb, bus bomb, van bomb, lorry bomb, or truck bomb, also known as a vehicle-borne improvised explosive device (VBIED), is an improvised explosive device designed to be detonated in an automobile or other vehicles.
A proximity fuze is a fuze that detonates an explosive device automatically when the distance to the target becomes smaller than a predetermined value. Proximity fuzes are designed for targets such as planes, missiles, ships at sea, and ground forces. They provide a more sophisticated trigger mechanism than the common contact fuze or timed fuze. It is estimated that it increases the lethality by 5 to 10 times, compared to these other fuzes.
An improvised explosive device (IED) is a bomb constructed and deployed in ways other than in conventional military action. It may be constructed of conventional military explosives, such as an artillery shell, attached to a detonating mechanism. IEDs are commonly used as roadside bombs, or homemade bombs.
A thermostat is a regulating device component which senses the temperature of a physical system and performs actions so that the system's temperature is maintained near a desired setpoint.
A mercury switch is an electrical switch that opens and closes a circuit when a small amount of the liquid metal mercury connects metal electrodes to close the circuit. There are several different basic designs but they all share the common design strength of non-eroding switch contacts.
In an explosive, pyrotechnic device, or military munition, a fuse is the part of the device that initiates function. In common usage, the word fuse is used indiscriminately. However, when being specific, the term fuse describes a simple pyrotechnic initiating device, like the cord on a firecracker whereas the term fuze is used when referring to a more sophisticated ignition device incorporating mechanical and/or electronic components, such as a proximity fuze for an M107 artillery shell, magnetic or acoustic fuze on a sea mine, spring-loaded grenade fuze, pencil detonator, or anti-handling device.
An electric arc is an electrical breakdown of a gas that produces a prolonged electrical discharge. The current through a normally nonconductive medium such as air produces a plasma, which may produce visible light. An arc discharge is initiated either by thermionic emission or by field emission. After initiation, the arc relies on thermionic emission of electrons from the electrodes supporting the arc. An arc discharge is characterized by a lower voltage than a glow discharge. An archaic term is voltaic arc, as used in the phrase "voltaic arc lamp".
The M734 multi-option fuze is a rangefinder and collision detection system used on 60mm, 81mm, and 120mm mortar shells as a trigger to detonate the shells at the most damaging heights of burst when combating four types of battlefield threats:
An electronic component is any basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused with electrical elements, which are conceptual abstractions representing idealized electronic components and elements.
An inertial switch is a switch, firmly mounted upon a vehicle or other mobile device, that triggers in the event of shock or vibration. It is a part of electrical circuits that may either enable or disable some function.
The MON-90 is a Claymore-shaped, plastic bodied, directional type of anti-personnel mine designed in the Soviet Union. It is designed to wound or kill by fragmentation. The mine is similar in appearance to the MON-50, but is approximately twice the size with a much greater depth.
The TM-46 mine is a large, circular, metal-cased Soviet anti-tank mine. It uses either a pressure or tilt-rod fuze, which is screwed into the top. Anti-tank mines with this type of fuze were capable of inflicting much more damage to armored vehicles, when compared to a typical anti-personnel mine.
An anti-handling device is an attachment to or an integral part of a landmine or other munition such as some fuze types found in general-purpose air-dropped bombs, cluster bombs and sea mines. It is designed to prevent tampering or disabling, or to target bomb disposal personnel. When the protected device is disturbed, it detonates, killing or injuring anyone within the blast area. There is a strong functional overlap of booby traps and anti-handling devices.
The SC 250 was an air-dropped general purpose high-explosive bomb built by Germany during World War II and used extensively during that period. It could be carried by almost all German bomber aircraft, and was used to notable effect by the Junkers Ju 87 Stuka. The bomb's weight was about 250 kg, from which its designation was derived.
In military munitions, a fuze is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze designs can be seen in cutaway diagrams.
An artillery fuze or fuse is the type of munition fuze used with artillery munitions, typically projectiles fired by guns, howitzers and mortars. A fuze is a device that initiates an explosive function in a munition, most commonly causing it to detonate or release its contents, when its activation conditions are met. This action typically occurs a preset time after firing, or on physical contact with or detected proximity to the ground, a structure or other target. Fuze, a variant of fuse, is the official NATO spelling.
A contact fuze, impact fuze, percussion fuze or direct-action (D.A.) fuze (UK) is the fuze that is placed in the nose of a bomb or shell so that it will detonate on contact with a hard surface.