Danaher Motion: New direct-drive motor technology cuts design time, life-cycle costs

Eliminating all mechanical transmission parts between motor and load—such as gearbox, belts, or pulleys—is inherent in the design of direct-drive rotary (DDR) motors.

By Control Engineering Staff February 26, 2004
Cartridge DDR motors are available in two frame sizes (three stack lengths per frame), with 230, 400, and 480 V inputs; 50-510 Nm (37-376 lb-ft) continuous torque range; and speeds to 1,200 rpm.

Eliminating all mechanical transmission parts between motor and load—such as gearbox, belts, or pulleys—is inherent in the design of direct-drive rotary (DDR) motors. The objective, of course, is added reliability more torque density, and smaller size. Installation concerns may have been holding some users back from considering DDRs.
Newly introduced Kollmorgen Cartridge DDR servo motors from Danaher Motion combine the best of two worlds. They bring the performance advantages of frameless direct-drive motors with the installation ease of full-frame motors. And this comes “at a significantly reduced price point than conventional direct-drive technology,” says the company.
Cartridge DDR motors feature simple installation, reportedly under 30 minutes, and an integrated high-resolution feedback device (sine encoder) aligned at the factory. The motor’s bearing-less design enables quick “mount and run” operation. And an advanced electromagnetic design provides up to 50% more torque density than comparably sized conventional servo motors. Other features of Cartridge DDR motors include:

  • Increased machine uptime resulting from maintenance-free operation;

  • Up to 20 dB less noise without the transmission; and

  • Increased accuracy (up to 50 times greater).

Tom England, product marketing manager at Danaher Motion told Control Engineering , “Cartridge DDR is a completely new format of direct-drive rotary motor that provides all the benefits of DDR technology in an easy-to-apply package, saving months of engineering application time. It’s the first direct-drive rotary solution that customers can easily and quickly apply, while gaining the performance benefits of increased throughput, fewer mechanical parts, zero maintenance, and inherently smaller package size.”

Danaher Motion explains that Cartridge DDR motors are competitively priced when compared to traditional servo systems with mechanical transmissions. It claims operating cost reduction of more than $10,000 on a single motion axis—over a five-year usage period—”even with a slightly higher initial cost.” Danaher thinks the lower entry cost and lifecycle savings will speed adoption of direct drive technology for new machine designs. Target industries include converting, packaging, printing, semiconductor manufacture, and factory automation.

—Frank J. Bartos, executive editor, Control Engineering, fbartos@reedbusiness.com