The force required to operate a lid is also affected by the ambient temperature.
In cool weather it may not stay open safely despite high force application, while very high temperatures make closing it more difficult; the lid will then barely close.
In a strut, the STABILUS gas spring is combined with a mechanical spring, which can be located on the inside or outside. This combines the advantages of the gas spring (speed control, end position damping) with those of the mechanical spring (little temperature dependency).
The effect of temperature on the extension force is reduced considerably, since the load is distributed between the gas spring and the mechanical coil spring.
This allows reducing the closing forces at high temperatures without increasing the opening force in cold temperatures (-30 °C).