Gas spring

A gas pressure spring ( also briefly referred to as gas spring ) is a pneumatic spring which uses under high pressure gas to provide the spring force. Advantages over coil springs from the suspension travel virtually independent force, the small footprint and the ability to integrate a damping mechanism may be the same in the spring.

Applications

Gas springs are often used for load distribution and are, for example, office chairs, as supportive of opening and holding device of flaps in vehicles ( trunk lid, hood ) or in the luggage compartment doors in the passenger compartment of airplanes to be found. Toolmaking gas springs replace conventional compression springs made ​​of steel due to their high power density.

Functioning and designs

The gas spring is a hydropneumatic adjustment and consists of a pressure tube, piston rod with piston and appropriate connectors. It is filled with a compressed gas, the amount of the pre- determined internal pressure. The pressure acts on the cross-sectional area of the piston rod. This results in a force in the extension. The piston with its overflow is only for cushioning and guidance. This force can be precisely defined within physical limits by the appropriate choice of the filling pressure.

Gas springs always consist of a cylinder and a piston movable therein freely. Depending on the application, both sides of the piston and are filled with gas only. More complex structures may still have a separating piston which separates two regions is filled with gas and oil.

In the simplest and most commonly used design is the entire interior with gas - usually nitrogen - filled. The piston has a small opening, through which the gas can flow and the cross-section determines the degree of damping. The component further comprises a small amount of oil, which is used for damping and lubrication. The seal against gas loss is on the leadership of the piston rod.

By the intrusion of the piston rod into the inner space there is reduced by the volume. The piston does (because of overflow 10) does not contribute to volume change. Because no gas can escape, the amount of substance of the gas remains constant, however. This results in a change in pressure, which is given for an ideal gas for isothermal behavior by. This result for the change in pressure in the interior:

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The restoring force resulting from the gas pressure and the cross sectional area of the piston rod. This results in an initial spring force.

• Spring (technology)
• Pneumatics
• Cylinder