Rigid locking in the direction of compression

The rigid locking of the VOB gas spring on compression (VOB 18-1) is used in applications where no cushioning effect is desired and where very short gas springs are required. The main applications are tilt adjustments on massage tables.

The VOB series is characterised by two fundamental features: the tube-mounted valve and the design of the inner and outer tube. The valve separates the two tube chambers. This special design causes the pneumatic medium to flow past the piston between the inner and outer tube. Rigid locking is achieved when the chamber is filled with oil that is hermetically sealed from the gas filling by the piston and the separator piston in the ring area.

Specification VOB 18-1


VOB 18-1
LockingRigid in compressive direction
In compression direction: rigid to [N] /   max. load [N]3,000
In extension direction: rigid to [N] /        max. load [N]1.5 x F1
Tube diameter28
Piston rod diameter10
Min. installation length excluding eyelet [mm]2 x stroke + 90
Stroke C [mm]20 - 300
Extension forces F1 [N]150 - 1,000
Progression ratio (F2/F1)< 1.7
Release force [N]0.4 x F1
Release travel, short [mm]-
Release travel, normal [mm]2.5≤ x ≤3.5
Recommended installation positionPiston rod pointing downwards
Permissible operating temperature-20°C to + 60°C
Permissible storage temperature-20°C to + 80°C