Variators suit rugged environments
Bonfiglioli is introducing new ranges of planetary speed variators for control of industrial power transmissions in rugged environments and where maximum durability and simple operation are required.
Bonfiglioli’s VBG and VBA series of mechanical variators are ideal for variable speed applications such as pumping or mixing and in environments such as exposure to weather, hazardous chemical and very dusty or high humidity conditions.
“These applications would normally require special enclosures that add significantly to the cost of the overall system,” said Bonfiglioli Transmission (Australia) general manager Malcolm Lewis.
“Mechanical variators represent a convenient speed control technology for many applications where versatility and ease of maintenance are essential. Because they utilise a submerged oil planetary system with an adjustable ring that is in a sealed unit, they can be used where other systems such as belts or electronic speed controls may be inappropriate,” he said.
To service these applications, Bonfiglioli’s expanded range of mechanical variators offers stepless speed reductions down to 6.5:1, with the ratio simply altered by means of an externally mounted handle. This system allows particular ease of use and minimal installation work.
The Bonfiglioli VBG series of variators are constructed of cast iron and include seven sizes, ranging from 0.2kW to 11kW.
The VBA series, which offers three sizes in the 0.12-1.5kW power range, has aluminium housing and external fins to optimise heat dispersion.
Features of both series include: space-saving planetary gears and high-efficiency rolling races machined to high tolerances so smooth, quiet running is guaranteed; gearing systems made from special steel that run submerged in lubricant, virtually eliminating wear, according to Bonfiglioli; the ability to be used in applications where overloads are likely to occur; and availability in a broad range of designs, suiting any type of support.
Unlike many current variable speed drives, the VB series is actually a torque increaser, according to the company. This gives the system designer confidence that required torque will be delivered though the entire speed range.
Bonfiglioli can also offer a differential style unit with the VBG range. This unit allows operation down to 0 rpm whilst maintaining full torque and offers substantial savings when compared to closed loop AC or field wound DC drives. An input adapter is available to fit the mechanical variators to standard IEC motors of the B5 type.
All Bonfiglioli variators support a wide range of optional accessories, such as gravity speed indicators, servo controls, proximity sensors, digital scanners and encoders.
31-Jan-2002