Mechanical Action Fuzing (switches) Flashcards
Definition of mechanical fuse
Any mechanical mechanism that is employed in a hazardous device and requires physical action or force to take place in order for the mechanism to function.
Definition of mechanism
The means by which an affect is produced or accomplished or the mechanical aspect in other words. Typed by function
Organic safety
Built in safety
What is a positive safety
Put into device afterwards
What is NC and NO
NC = Normally Closed
NO= Normally Open
Switch contacts on bottom can have 3 positions
Normally Open
Normally Closed
Combination of both
What does a safe arm do?
A safe arm is put in place so that a device can be safely handled until the device is ready to be fired.
Arming Switch
Functions the device
FUZE VS. FUSE
FUZE: Ignition source inside an explosive device.
FUSE: A wire, bar, or strip of fusible metal inserted for safety in an electric circuit.
What are the normal states of rest for the switch with no outside influence.
NC OR NO
TYPES OF COMMERCIAL SWITCHES
Toggle Switch
Slide Switch
Relay Switch
Vapor Switch
Knife Switch
Micro Switch
Mercury Switch
Vibratory Switch
Magnetic Switch
Push Button Switch
Toggle Switch and Slide Switch
Moves the lever in order to open or close. In the open position the circuit is not complete. When closed it completes the circuit.
Relay Switch
Electromagnet to create a magnetic field that closes a circuit, turning a larger electrical current on or off
Vapor Switch
Environmentally safe version of the mercury switch
Knife Switch
Think about Frankenstein pulling power. You pull to complete circuit
Micro Switch
Can be used as pressure or as pressure release.
Mercury Switch
Best switch on market. Uses mercury that moves to one side or the other to complete circuit.
Vibratory Switch
Motion activated. VERY SENSITIVE
Magnetic Switch
The movement of the magnet can open or close the circuit
Push Button Switch
Pushing on it opens or closes it (Keyboard Key)
Improvised Mechanical Switch
Clothes Pin
Loop Switch
Pressure Switch
Foil Switch
Tilt Switch
Tilt Switch (2)
Knife Switch
Time Device
Mouse Trap
Clothes Pin
You can put metal on the legs and a non-conductive material between it and once it’s pulled out it closes the circuit.
Loop Switch
The loops are around the wire and if they are pulled (opening) box it will complete the circuit
Pressure Switch
Stepping on it can make it go off or releasing the pressure.
Foil Switch
The foil is separated by a non conductive material between the two sheets of foil. Once removed the foil touches closing circuit.
On the X-Ray look for wires that are going to nothing and are suspended in air.
Tilt Switch
The motion closes the circuit
Knife Switch
Uses trip wire to pull knife to close the circuit.
Time Device
Can be in various forms: Clock
Mouse traps
Can be used in various devices
Trip Wires
A wire attached to 2 different points a fixed location and then to the switch. It can either open or close the switch to complete the circuit.
When you encounter them you have 2 options if in a tactical environment you should mark it and and continue. If in search you should ID it and figure out how it works.
Switches by function
Pressure
Pressure releases
Pull
Tension release
Anti-Disturbance
Barometric
Hydrostatic
Thermal
Time Delay
Pressure
Force applied directly to a moveable plunger or flexible material
Pressure Release
Apply the pressure to the device and functions once pressure is removed. Victim Activated
Pull
The force exerted against a wire, cord, or trip wire to complete firing system. Can do the following: Remove pins, close electric circuits, pull abrasive material through a match compound.
Typically a trip wire
Tension Release
Incorporates taut trip wires. Occurs when a line under tension is cut or broken
Anti Disturbance
Used to sense any movement to function firing system
THE MOST HAZARDOUS
Anti Disturbance
Used to sense any movement to function firing system
THE MOST HAZARDOUS
Barometric
Detects the change in air pressure.
Hydrostatic
Balloon that will expand or contract on depth functioning the device with increase pressure.
Thermal Bimetal Switch
Operates on change in temp
Time Delay Switch
Time limit can be:
Mechanical
Chemical
Material fatigue
Mechanical delay
Alarm on clocks must remove coating off of clock to work.
Chemical time delay
Example M-1 time Pencil
Material Fatigue
Any degradable material can be used to construct a time delay
