Posted to News on 2nd Oct 2012, 16:12
Bevel gearboxes - the modern replacement for worm gears
Lenze says its GKR bevel geared motors are a suitable replacement for worm geared motors, offering potential savings in energy costs. The extra purchase cost is paid back in only a few months of continuous running because the efficiency improves from 50-70 per cent to 96 per cent. These geared motors are available for motor powers from 60W to 7.5kW with output torques up to 450Nm and ratios up to i=76.
GKR bevel gearmotors contain two gear stages: the first stage is a helical gear with a small ratio; contained within the cast housing is a bevel output gear stage with case-hardened steel teeth. Modular options to aid mounting include male or hollow shafts, foot mounting, and single or double flanges.
There are three areas where the bevel gearbox shows advantages over worm designs. First the backlash is low, at typically around 10 arc-min; this makes the gearboxes suitable for accurate positioning tasks, and they can be combined with servo motors. Second, the low backlash is maintained as the wear rate is insignificant over normal lifetimes. Again, this enables the gearboxes to be used for positioning with servo technology. The third advantage is the high efficiency, which is a constant at 96 per cent irrespective of ratio. Although the reduction in energy cost for a single geared motor may be relatively small, where there are multiple drives running continuously the savings can be thousands of pounds a year compared with worm geared motors.
Lenze GKR geared motors are available in four sizes with up to 25 closely stepped ratios per size. Additional options for the motors include fans, encoders, brakes and integrated frequency inverters. Follow the link for more information about GKR bevel geared motors.
