Pantographic knife
Encyclopedia
A pantographic knife or paratrooper knife is a folding knife
whose blade is opened by a unique scissors method. The blade has a slightly longer tang than a folding knife heel. The handle is symmetrically segmented and articulated to fold away on both sides to grip the longer tang. The manner is similar to a balisong knife (also called a butterfly knife in western countries) - with which it is often confused. Unlike the balisong knife handles that swing freely and independently, the pantographic knife uses a pantograph
linkage
to keep the handles aligned during opening and closing. The pantographic knife is very strong when compared to most other folding knife designs, being joined at several points and along several planes
- this increases the force
required to break the blade away from the handle.
By enclosing the blade
on both sides, double edged blades can be used.
This knife is also known as a paratrooper
knife, although it was never issued as such. The mechanism includes a collar that travels up the blade. This looks similar to an OTF gravity knife
used by German paratroopers.
Operating this mechanism is complex, and not easily done one-handed.
Knife
A knife is a cutting tool with an exposed cutting edge or blade, hand-held or otherwise, with or without a handle. Knives were used at least two-and-a-half million years ago, as evidenced by the Oldowan tools...
whose blade is opened by a unique scissors method. The blade has a slightly longer tang than a folding knife heel. The handle is symmetrically segmented and articulated to fold away on both sides to grip the longer tang. The manner is similar to a balisong knife (also called a butterfly knife in western countries) - with which it is often confused. Unlike the balisong knife handles that swing freely and independently, the pantographic knife uses a pantograph
Pantograph
A pantograph is a mechanical linkage connected in a special manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a second pen...
linkage
Linkage (mechanical)
A mechanical linkage is an assembly of bodies connected together to manage forces and movement. The movement of a body, or link, is studied using geometry so the link is considered to be rigid. The connections between links are modeled as providing ideal movement, pure rotation or sliding for...
to keep the handles aligned during opening and closing. The pantographic knife is very strong when compared to most other folding knife designs, being joined at several points and along several planes
Plane (mathematics)
In mathematics, a plane is a flat, two-dimensional surface. A plane is the two dimensional analogue of a point , a line and a space...
- this increases the force
Force
In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity , i.e., to accelerate, or which can cause a flexible object to deform...
required to break the blade away from the handle.
By enclosing the blade
Blade
A blade is that portion of a tool, weapon, or machine with a cutting edge and/or a pointed tip that is designed to cut and/or puncture, stab, slash, chop, slice, thrust, or scrape animate or inanimate surfaces or materials...
on both sides, double edged blades can be used.
This knife is also known as a paratrooper
Paratrooper
Paratroopers are soldiers trained in parachuting and generally operate as part of an airborne force.Paratroopers are used for tactical advantage as they can be inserted into the battlefield from the air, thereby allowing them to be positioned in areas not accessible by land...
knife, although it was never issued as such. The mechanism includes a collar that travels up the blade. This looks similar to an OTF gravity knife
Gravity knife
A gravity knife is a knife with a blade contained in its handle, and which opens its blade by the force of inertia or gravity. As the gravity knife requires gravity or inertia to propel the blade out of the handle, it differs fundamentally from the switchblade, which opens its spring-propelled...
used by German paratroopers.
History
Examples of pantographic knives with patent markings D.R.G.M. (Deutsches Reich Gebrauchsmuster) indicate production in Germany during the war, but do not imply military issue. Although this design predates WWII, Records of German paratroopers having genuinely issued pantographic knives have not surfaced. To complicate identification, samples made with German army markings (brass handles with text in English language) seem to be post war (1948) marketing attempts capitalizing on the term Paratrooper.Function
In this illustration:- Figure A shows the closed knife, with blade retracted.
- Figure B shows the pantographic legs opening. The collar is shown sliding down the blade.
- Figure C shows the blade almost extended.
- And finally, Figure D shows the pantographic legs folded together, making a handle that is half as long as when the knife was closed.
Operating this mechanism is complex, and not easily done one-handed.