Project Challenge
Reliable Drive Technology From NORD
NORD DRIVESYSTEMS is one of the leading international full suppliers in the industry and supplies fully matched drive systems consisting of gear units, motors and frequency inverters for more than 100 branches of industry. For the Danish cow brushes, the drive specialist supplied a powerful combination consisting of a two-stage NORDBLOC.1 helical geared motor and a NORDAC BASE frequency inverter. The motor, the controller and the gear unit form a unit attached to the cow brush, which does not move with the rotation of the brush but rather remains rigid. “With the products from our competitors, the motor and the gear units move together with the brush. Faults and wear are therefore inevitable”, explains Papuga and stresses: “Our cow brushes are the only ones on the market with a strong drive construction. This rules out cable breaks.” A universal joint between the motor and the brush as well as 40 mm stainless steel bearings in front of the motor also ensure maximum durability. Both components absorb the torques and reduce the load on the motor.
In addition, the NORD drives are energy efficient in operation, have a compact design, great reliability and a long service life. The innovative design of the NORDBLOC.1 helical geared motors guarantee quiet running and safe operation. Thanks to their wash-down design, they meet even the most stringent hygiene requirements. The gear units do not have any separating joints or closing caps. This increases the stability of the product and at the same time provides a smoother surface on which neither liquids nor solid materials can accumulate. A Certonal coating protects the electronics against condensation.
Greater Safety and Efficiency Thanks to Intelligent Functions
The cow brushes are controlled by a NORDAC BASE frequency inverter. The compact and robust inverter is specially designed for simple applications and is especially economical. Through the integration of a PLC, application-specific functions related to the drive unit can be efficiently programmed and parameterized in the same way as other functions of the NORDAC BASE – SK 180E. The brush starts to rotate as soon as a cow rubs against it. If there is too much resistance, for example if the tail gets trapped, the brush stops and then turns in the opposite direction. In addition, the direction of rotation changes on each start and at intervals of five minutes. This ensures even wear of the brush elements. “This intelligence is very important for us. We also like the fact that we can make minor changes to the program”, says Carsten Papuga. “For example, we can reduce the torque if we use the same brush for smaller cows – because smaller cows have shorter tails.” Another advantage is the energy saving function for the partial load range: The motor power adapts to load changes automatically according to actual requirements. This ensures energy-efficient operation. This is also helped by the use of gear drives. These can achieve an efficiency of up to 98 percent – and therefore use at least 50 percent less power than comparable cow brushes. Most manufacturers use single-phase motors with worm gear units, whose efficiency can be as low as 60 percent in the worst case. With regard to service life, they are also inferior to the helical gear units used by Celi Invest.