Mode of operation AWP release heads

In “Operation of a gas spring” we have found out that to open the valve of a blockable gas spring a release pestle is built in the gas spring. The force to press this pestle is depending on the filling pressure of the gas in the gas spring. The higher the filling pressure, the more force is required to move the pestle. This results from the fact that the valve pestle plate, as well as the piston is claimed by the gas filling. The necessary activity force amounts to approximately 25% of the filling force (F1), according to implementation of the valve a little bit more or less. Does the filling force (F1) amount to 500 Newton, for example, an activity force of 125 Newton is calculated. For years away at market offered release heads for Bowden cable did set under this force around half, so that regarding to our above-mentioned example an activity force of approximately 62,5 Newton is necessary at the Bowden cable to move the piston rod. Additional levers were necessary to get a rational reduction of the activity force. Mostly additional levers with a gear ratio from 1:2 to 1:6 were used at the other end of the Bowden cable. The force will of course be reduced, but you have high frictional forces in the Bowden cable which will be increased if the Bowden cable is fixed with a radius and curve. Big, bulky, a design disaster.

Now the products of AWP are used. We reduce the pestle force with a special, purely mechanical release head around the factor 21. Calculated with our above-mentioned example you only need an activity force for the gas spring of 5,95 Newton. But how does this reduction operate? The principle is as easy as brilliantly. The force reduction is realised by using a “short-releasing valve” that only require a maximum way of 1 mm to open the gas spring. The system is based on a knee lever functioning release head to achieve this reduction of the force.

By this force reduction design possibilities were opened for key elements which are small and attractive.


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