The ETR251/46 gear rack drive is a low-maintenance, purpose-designed drive for opening and closing swinging-environment vents in Venlo-type greenhouses. The mixture of TR251/46 gear rack drive and aEP RW electric motor gearbox plays a part in an optimum greenhouse environment thanks to accurate positioning of the air vents.
The self-supporting TR251/46 gear rack drive comprises a zinc-plated C-profile with a planetary gearbox built-in compact gear rack drive unit. The TR251/46 gear rack drive is mounted to a greenhouse gutter using the item clamp-installation forks or bows.
Thanks to the apparatus reduction stage (i-2.76) and the pinion of the TR251/46 gear rack drive, the drive torque is effectively converted into a optimum rack force of 4200 N. Track rollers in the C-profile and information blocks ensure stable extension and retraction of the rack. The drive shafts of the TR251/46 equipment rack drive have long, flat-sided journals. This makes it possible to suit drive shafts (prefab) installed with weld/sleeve couplings or chain couplings, after the house units have been mounted. The drive shafts are locked in the couplings by the accompanying shaft retaining clips. The TR251/46 gear rack drive is easy to maintain.
A ETR251/46 gear rack drive with other C-profile lengths 
and rack lengths is on request.