Cutting chain is best done with three hands: One for holding the chain and the other two for wielding the heavy cutter. Now imagine a chain breaker that can be held and operated with one hand. The other hand, free, could position and hold the chain link.
That's the idea behind a hydraulic device called a PowerCylinder. It gives ordinary humans the chance to be called "crusher." It also sits as easily on the end of an actuator—a self-contained hydraulic package that needs neither a separate reservoir nor a leaky pipe to tie to it.
Made by the LatchTool Group, the device stacks three unusual valves together to generate speed over force first, then force over speed, says Company Operations Director Sean Fry. Each FastFlow valve uses an O-ring and retainer spring to control fluid transfer through a series of orifices which are spaced equally around the face of a piston. The design permits fluid to flow much faster than it would through the constrictions of an ordinary check valve, especially as system dimensions shrink, Fry explains.
The three stage cylinder relies on increasing hydraulic pressure to open successive FastFlow valves. As each valve opens, the piston ram moves less distance but exerts greater force. Resistance at the ram triggers the next valve to open as the differential pressure shifts between sides of the piston. In this way, a pair of power pliers employing the technology produces, at its jaws, a 47:1 increase in the force applied at the handgrips, Fry says.
The company's first forays into handtools such as locking pliers should lead off a slew of other applications, Fry says—everything from aircraft ailerons to robot end effectors.
Power At Hand
A multitude of spring-and-ball check valves might do what a single FastFlow valve can -- move lots of fluid with minimal resistance. They wouldn't do it cheaply, though.
To find out more about LatchTool, read the company's latest PowerCylinder white paper http://rbi.ims.ca/4397-534. To watch a couple no-nonsense video presentations, see http://rbi.ims.ca/4397-535. To speak with a LatchTool representative, call 719-488-8800