Integrated gear motors solve material-handling needs

Permanent-magnet ac motors (also called synchronous motors) from Bison Gear impart advanced velocity control to designs previously necessitating full servo control. The motors accept mounting of worm or high-efficiency hypoid gearing in various orientations to accommodate the needs of industrial machinery, conveying, and packaging applications.

Gearmotors have long been an industryworkhorse. Their greatest advantage is relatively high torqueat low speed, making them suitable for a range of uses acrossindustries with those requirements.

Changes in machine design are impacting what gearmotor manufacturers are offering. For instance, the growth of compact machine designs makes space considerations a critical design priority. So in some cases, designers may have to sacrifice features — for example, to implement the needed gearmotor size while accepting use of less efficient gearing.

Other trends impacting designs include more customized offerings based on end-user requests for more customized solutions that precisely fit design requirements. More manufacturers are offering customized solutions using more of their in-house engineering resources. This helps simplify the design process from the customer’s point of view. In addition, more custom offerings mean greater integration with other components in a design — leading to overall improved connectivity as well as fewer compatibility issues.

GEARMOTORS IN CRANE APPLICATIONS

Consider one application — that of a slew crane made by Zurich-area-based Swiss crane manufacturer WOLFFKRAN. In fact, WOLFFKRAN is a world leader in slewing tower cranes, and its trolley (saddle) and luffing jib cranes are employed around the world for their robustness and easy assembly at construction sites.

Slew cranes typically include a stationary base, undercarriage, mast, slewing ring, and jib and hoist — at the top of the mast to place loads within the jib's circumference of reach. Now, WOLFFKRAN uses standard hoist gear units as well as custom gear units from SEW-EURODRIVE for power transmission optimized to the tight footprint of its slew cranes — and the harsh outdoor settings that all cranes must endure.

Hoist winches on the cranes are a key subsystem ... often transporting loads of 6 to 60 metric tons several hours a day. Plus the trend toward ever-taller buildings means that cranes' lifting distances are steadily increasing … so now it’s not unusual to see hoist winches that wind and unwind 1,000 meters of cable to execute load-transporting functions. Such cranes (and their drives) see considerable load.

For one such crane design, WOLFFKRAN required a hoist drive capable of delivering a nominal torque range of 27.5 to 175 kNm; it also needed an increased center distance to arrange the motor and rope drum on one side of the gear unit. Gear and gearmotor solutions from SEW-EURODRIVE satisfy these parameters. Oversizing of gear units is unnecessary because a U-shaped arrangement of rope drum and motor is implemented with a larger center distance; a protruding intermediate shaft accommodates the mounting of a disk brake.

In fact, besides the hoist gear units, SEW-EURODRIVE also supplies the drive units for WOLFFKRAN’s crane trolleys.

Australia-based BCS Group chose NORD's 92.1 series two-stage helical-bevel gearmotors with integrated ac drives for a sorting application at a customer's material-handling facility.

GEARMOTORS IN INTRALOGISTICS

The intralogistics industry is a fast-growing market — and motion-component suppliers aim to address the industry’s needs.

One solution for large-scale intralogistics is the NORD LOGIDRIVE, a highefficiency gearbox integrated with an IE4 permanent-magnet synchronous motor and decentralized variable frequency drive. The VFD and IE4 motor support large speed ranges through a single gearbox-and-motor combination.

The decentralized drive units are also service friendly thanks to plug-and-play technology. The modular design means all of the integrated motor’s components can be individually serviced — in turn minimizing maintenance and repair costs. With an aluminium housing and compact design, the integrated motor is also lightweight and unobtrusive.

Another option for intralogistics applications is a line of two-stage helicalbevel gearmotors paired with VFDs for distributed control. In fact, Australia-based systems builder BCS Group recently employed these motors in a new materialhandling facility run by freight-transport company Toll IPEC. The facility can sort 35,000 parcels per hour.

Such operations require an extensive conveyor system to move parcels around the facility. BCS chose upwards of 1,000 of NORD’s 92.1 series two-stage helicalbevel gearmotors with integrated ac drives for the job.

SEW-EURODRIVE gear and gearmotor drive units power axes on WOLFFKRAN cranes.