While everyone is going around discussing how awesome sliced bread is (as if we didn’t already know that), another invention had already been registered at the patent office before sliced bread was even a thing. It’s a handy piece of equipment called the Tirfor®.
Also referred to as the Griphoist® or a German come-a-long, the Tirfor® is a registered trademark of the Tractel® Group, which was founded in 1941. It’s a pulling and lifting device that operates in conjunction with wire rope that passes through the machine. The device is controlled by two pairs of jaws that operate alternatively to drive levers, which allow the movement of the wire rope or cable for almost unlimited pulling length or lifting height with pinpoint accuracy in positioning loads. So yes, it’s awesome, but what exactly is the point of origin of it’s awesomeness?
French inventor, Mr. Simon Faure, originally conceived the design and filed a patent for what eventually would become the TIRFOR® in 1929, which barely predates the first release of sliced bread in 1930. This design laid the groundwork for The Tractel® Group who would eventually acquire a trademark license for the hoist themselves. However, extensive testing delayed its first official release until the early 1940s.
According to the Griphoist® manual, Tractel® also created The Tirfor® Principle in order to help those unclear with how to operate the device effectively. The general idea of its operation mainly involves a ‘hand-over-hand’ action. While one hand pulls, the other one changes position in order to pull in turn. The jaws grip the wire rope without damaging it and alternately haul it during forward motion and clamp it during reverse motion. The effect is transferred to the jaws by means of two levers. One for forward motion and the other for reverse motion. They act by means of a cam system on the keys that command the automatic clamping of the jaws on the rope. The keys function due to the jaw grips being brought together or separated by means of keys that are actuated by levers called jaw-links. When the jaw-link is moved to the left, the jaws are clamped on the wire rope in order to draw it or maintain it in position. When the jaw-link is moved to the right, the jaws are unclamped in in order to allow the wire rope to slip through, but only in the direction opposed to the motion of the wire rope.
Needless to say, the Tirfor® can be an essential piece of equipment for many types of applications including heavy machinery, bridge and roadwork, rope/cable tensioning, load shifting, and more. But interestingly, it also predates the first release of sliced bread by almost a year. So, it’s easy to say that the Tirfor® is the best thing since sliced bread, but in reality, sliced bread is the best thing since the Tirfor®.
· "Tractel Tirfor Machines: Original & Best, the Rest is History."
https://www.specialisedforce.com.au, Specialised Force Pty Ltd, 2017,
· Tractel Group. TIRFOR sales manual. Luxembourg, Tractel S.A.