When your CNC or machine tool system calls for a drive system to position workpieces with high accuracy, well-proven rack and pinion drive technology offers several advantages such as long travel, high-speed, ruggedness and efficiency, to name a few. But when it comes to cutting, grinding, milling, shaping, boring and other demanding processes — especially those involving complicated dimensions and shapes — your drive system must exhibit optimal stiffness and effectively minimize or eliminate the backlash that can otherwise hinder positioning accuracy. This blog post will describe ways to achieve exceptional positioning accuracy via preloaded servo reducer systems that eliminate backlash.
Preloading Options: A Matter of Control
To eliminate backlash in a rack and pinion drive system, it’s important to create a preload that accurately controls torque at the output rack and pinion or pinion ring gear axes. That’s why we offer two rack and pinion drive systems that comprise two rack and pinion reducers — coupled mechanically or electrically, depending on the application — with output pinions preloaded against the rack. Our DualDRIVE mechanical preload system offers simple control and requires just one motor. TwinDRIVE — an electrical preload system — allows greater preload control using two motors along with a special motor controller. Here’s how they work:
- DualDRIVE achieves a closed-loop mechanical preload by spring-loading or torsionally winding one pinion against the other. One pinion is fixed and the other is spring-loaded. DualDRIVE needs just one motor, and no special controllers are required.
- TwinDRIVE technology creates an electrical preloaded closed loop by braking one pinion against the other pinion, which does the driving. These systems incorporate two motors and gearboxes for use with CNC control.
Redex SRP, DRP, KRP and KRPX Series rack and pinion reducers, together with DualDRIVE or TwinDRIVE technology, let machine designers create zero-backlash preloaded systems that achieve precise positioning and improved stiffness in CNC applications. These reducers feature optimized radial and torsional stiffness, very high linear accuracy, compact sizes and precision geometry for meshing with the rack. They can be implemented in the following ways:
DualDRIVE
- Two Right Angle SRP planetary reducers (SRP DualDRIVE Kit)
- Two Right Angle KRP planetary reducers (KRP DualDRIVE Kit)
- One Right Angle DRP includes two planetary reducers in one housing (DualDRIVE)
TwinDRIVE
- Two SRP planetary reducers (SRP TwinDRIVE Kit)
- Two KRP planetary reducers (KRP TwinDRIVE Kit)
- One DRP including two planetary reducers in one housing (TwinDRIVE)
Zero-Backlash Drives Produce High-Quality Machined Parts
In demanding CNC and machine tool applications, lost motion or backlash in your drive system is not an option. With Redex gear reducers as the basis for zero-backlash preloaded rack and pinion drive systems, you’ll effectively eliminate backlash — achieving exceptional stiffness and precise positioning to produce machined parts that meet your exacting requirements.
For more information about Redex DualDRIVE, TwinDRIVE and planetary reducer solutions, visit our product page.