Rotary Tables - Motion Control Tips

Expanded precision rotary indexer line from Nexen now motor/gearbox-ready

August 30, 2018 By Miles Budimir Leave a Comment

Nexen’s Motor Ready Sealed (MRS) precision rotary indexer maintains the benefits of the company’s existing patented precision roller pinion drive design – zero backlash, high precision, high torque, and high acceleration – while delivering significant new benefits. A high roller pinion-to-gear ratio lets designers direct drive the system with the addition of a servo motor – eliminating the cost of a reducer. This also reduces engineering and installation time. For high-load applications, the designers can drive the system with a reducer/motor combination. The gear-to-pinion reaction loads are fully supported so the servo motor shaft is not subjected to radial loading, which eliminates the need for costly high output capacity reducers in high load applications. All of these features reduce engineering and installation time.

Highlights of the MRS precision rotary indexer include:

High indexing precision – one-way positional accuracy up to ± 31 arc-sec and one-way repeatability up to ± 5.2 arc-sec
Zero backlash – unlike other drive systems there is zero backlash from the motor through the driven load
Acceleration – up to twice as fast as other technologies
High speed – up to 304 rpm
Motor/gearbox ready for faster installation
Sizes: 150, 250, 350 mm output bolt circle diameter, with large open center to optimize performance in small spaces
Fully sealed, IP65 rated
Low maintenance and long life

The MRS is suitable for precision rotary indexing applications such as machine tool, and semiconductors, robotics, automated welding, medical packaging, assembly, cutting systems.

For more information, visit www.nexengroup.com.

Oriental Motor 60-mm DG II rotary actuator with AlphaStep AZ Series absolute encoder stepper motor

August 29, 2018 By Lisa Eitel Leave a Comment

Oriental Motor is pleased to expand the DGII Series product lineup and AlphaStep hybrid control system with the introduction of the new 60 mm DGII rotary actuator.

The DGII Series is a line of products that combine a high rigidity hollow rotary table with an AlphaStep absolute encoder AZ series closed loop stepper motor and driver. It retains the ease of use of a stepper motor, while also allowing for highly accurate positioning of large inertia loads.

The new DG II retains the ease of use of a stepper motor while allowing for highly accurate positioning of large inertia loads.

The smaller 60 mm frame size is equipped with an AlphaStep AZ Series absolute encoder stepper motor. This new rotary actuator is available to be used with 4 types of AZ Series DC input drivers … stored data type, pulse input driver with built-in RS-485 communications, pulse input type and multi-axis driver with EtherCAT communication.

It is a complete cost-effective accurate rotary actuator system that help eliminate the need for additional sensors. This new combination can work in traditional applications where step and direction are required, or, in applications where PLC or Touch Screens (HMI) are being used, without the need for additional modules connected to the PLC. The end result is a more efficient and energy efficient product that is compatible with a wider range of master controller types and control methods.

For more information about the Oriental Motor 60-mm DGII Series rotary actuator, call (800) 468-3982 or visit this deep link on orientalmotor.com.

Since its founding in Japan in 1885, Oriental Motor has been a world leader in motion control systems. For over a century, we have concentrated on technological advancement and product design improvement — an emphasis evident in the sophisticated devices we market today.

Zero-backlash servo rotary indexing table from Sankyo Automation

April 10, 2018 By Lisa Eitel Leave a Comment

The Sankyo Automation RollerDrive Reducer is a precision gear reducer that uses a zero-backlash roller gear mechanism. The unit is constructed from an input shaft and a turret (output shaft) that is assembled with roller followers. The roller followers are preloaded against a screw-like input shaft to eliminate backlash.

Sankyo servo indexing tables offer a constant lead cam with a servo motor drive for programmable motion. Sankyo servo indexing tables provide fast highly accurate motion, with the added capability to move medium to heavy loads. The preloaded cam and turret provides a high performance zero-backlash servo indexing table for all automation needs.

The RU Series servo indexing table is available in 11 different sizes. These servo-indexing tables come with varying ratios to maximize the motor’s torque capacity, speed requirements and enhance the overall accuracy. Special applications may need double reduction ratio of the internal cam (and an additional reducer) to provide large torque capacities or slower speed. Additional features of the RU Series servo indexing table include:

Zero-backlash operation, as the RollerDrive uses a preloaded mechanism to completely eliminate backlash and deliver output motions that are faithfully true to input commands
RollerDrive technology that incorporates a cam with a high gear reduction to deliver large torque capacities with smaller servo motors
A second reducer option … as multiple reducer options keep the servo at optimal rpm

In addition, the reducer’s rigidity makes it suitable for machining applications. An exclusive output turret bearing and cast-iron housing tolerates heavy vibrations associated with machine tool applications. Plus the table is versatile for retooling … so the RU Series can keep pace with the ever-changing tooling requirements.

Plus short settling times mean the RollerDrive provides fast and highly accurate dynamic motion.

For more information, visit the Electromate page on the Sankyo RollerDrive RU Series Reducer.

New Oriental Motor DGII rotary actuators with AZ Series dc input drivers

February 20, 2018 By Lisa Eitel Leave a Comment

Oriental Motor now sells an expanded lineup of DGII Series rotary actuators — including two new dc input AZ Series driver options.

As the demand for complete high-accuracy and efficient rotary actuators grows, Oriental Motor has answered with the introduction of the AZ Series dc input drivers. This allows for more applications that are using dc power to be considered. The DGII rotary actuators with AZ Series can work in traditional applications where positional accuracy is needed or in applications where PLC or Touch Screens (HMI) are used, and without the need for additional and expensive module(s) added to the PLC. The end result is an efficient and complete product available to a wider breadth of master controller types and control methods.

The new 24/48 Vdc driver options is available for both the DGM85 and DGM130 DGII standard models or models with built-in electromagnetic brake. In addition to the new 24/48 Vdc drivers, the expanded AZ Series product line-up also includes AZ Series Pulse Input Driver with built-in RS-485 communication and multi-axes driver with EtherCAT communications.

Optional redesigned mounting pedestals for the DGII rotary actuators with AZ Series motors are also available. This is a useful installation pedestal that enables the DGII Series to be used as a direct drive motor. Applications that need height and installation from the side can also be performed, expanding the range of available operations.

For more information about DGII Series rotary actuators, visit orientalmotor.com/rotary-actuators.

What is a rotary indexing table?

February 16, 2018 By Miles Budimir Leave a Comment

Rotary indexing is a process where repeated angular displacement during a machine cycle is followed by motionless dwell. A rotary indexing table is specifically designed to make repetitive moves around a platform. Essentially, they are highly precise work-positioning devices that index parts to be worked or machined in multiple operations.

The PRD ring drive system from Nexen is a high-resolution indexing system. It features precision to +/- 11 arc-sec, repeatability to +/- 1.2 arc-sec, and can handle loads up to 1,575 kN and speeds to 94 rpm.

A rotary indexing table is an integrated motion system. They typically consist of motors and mechanical power transmission devices along with encoders, sensors and controllers. Tables use electric motors for either cam drives or servo tables. Mechanical cam indexers are relatively low cost and only index to set angles, but are capable of precision moves.

Important parameters for rotary indexing tables include the needed resolution of the application (or the smallest increment to move or measure), the required repeatability and accuracy, and other mechanical parameters such as acceptable levels of backlash or hysteresis. Another key parameter is the loading including torque, axial, radial, and moment loads. These can impact the type and size of the indexer used in a given application.

A rotary indexing table can be used in many applications including manufacturing, inspection, and assembly tasks. For instance, assembly, machining, and bottling machines all use indexers. Usually, they take one piece around to work areas or move arrays of relatively small parts around stations for sequential machining or assembly tasks.

Direct-drive (DDR) rotary servo tables from IntelLiDrives have tighter resolution

April 25, 2017 By Lisa Eitel Leave a Comment

Direct drive torque motor (DDRs) from IntelLiDrives have resolution up to 0.1 arc-sec; Incremental or Absolute encoders; precision cross-roller or ball bearings; and (optional) matching drives.

Benefits of direct drive (DDR) from IntelLiDrives

IntelLiDrives rotary tables eliminate backlash and provide a stiff mechanical system for highly dynamic applications. Integrated with precision bearings and ring encoders, these rotary tables provide ultimate performance in rotary indexing applications compared to other mechanical transmission rotary systems.

Accurate positioning is assured with contact-less ring encoder. The motor and rotary encoders are directly coupled to eliminate coupling backlash. The low inertia and zero backlash make IntelliDrives DDR rotary tables the ideal solution for applications requiring frequent directional changes.

Benefits of the table’s low profile abound as well. The rotor low inertia improves the start-and-stop behavior and velocity control significantly compared to conventional rotation stages, due to the light-weight direct-drive motor. The result is precise bidirectional speed and position control, which is critical for high speed motion contouring.

DESTACO’s GTB series servo-positioning rotary tables offer exceptional torque in compact design

April 3, 2017 By Lisa Eitel Leave a Comment

DESTACO, the industry’s leading global provider of high-performance automation, workholding and containment solutions, is excited to announce that it will debut its new family of GTB Series Servo Positioning Rotary Tables in Booth No. 1436 at the Automate 2017 Trade Show, held from April 3-6, 2017, at McCormick Place in Chicago. More after the jump.

The GTB Series of Servo Positioning Rotary Tables are the first products to be launched as part of DESTACO’S technical partnership with Techno Dynamics, Inc. (TDI), a Japan-based company and leader in the development of motion solutions.

“DESTACO has a 100-year history and an outstanding track record of developing highly engineered solutions to help our customers around the world achieve unparalleled precision and productivity,” said Byron J. Paul, President of DESTACO. “The GTB Series Rotary Tables expands our technology base and advances our solutions to the market. Our customers will have a full range of options – from traditional, proven mechanical fixed-function rotary tables to fully flexible servomotor-based rotary tables for use in changing operating environments and applications.”

The GTB Series features a roller-gear drive and is a lifetime-lubricated solution that has been designed and engineered to deliver high torque, with high speed and motion flexibility to meet the demanding payload requirements in a wide variety of general industrial rotary table applications. Available in four models – GTB40, GTB63, GTB80 and GTB100 – the GTB units are 34% lower in height and 64% lower in weight when compared to competitive models, while being able to deliver 1.4 times the torque. The unit’s lifetime-lubrication design also eliminates the need for maintenance.

“The new GTB Series rotary tables feature the latest design technologies to produce a very high torque that is comparable to much larger units, but in a very compact size,” said Matt Girand, DESTACO’s Vice President of Research, Development and Engineering. “In addition, the units can be mounted in both vertical and horizontal orientations, which is a significant benefit since the user does not have to worry about changing the application or purchasing a different unit.”

In addition to flexible orientation, each model can support a wide range of off-the-shelf servomotors for maximum motion flexibility and performance. Each size features a direct motor coupling that eliminates backlash, which is a crucial consideration in high-accuracy rotary table applications. An optional gear reducer is available for applications that require increased torque.

For more information about DESTACO’s new GTB Series Servo Positioning Rotary Tables, please visit destaco.com.

DESTACO, a Dover company, is a global leader in the design and manufacture of high-performance automation, workholding and remote-handling solutions. The company serves customers in a variety of end-markets, including the automotive, life sciences, consumer goods, packaging, aerospace and nuclear sectors.

Built on a legacy of more than 100 years, DESTACO offers a comprehensive portfolio of products designed to engineer precise movement, placement and control solutions that drive productivity and uptime for manufacturers around the world. The DESTACO family of products consists of industry-leading brands such as DESTACO Manual and Power Clamps, CAMCO and Ferguson Indexers, Robohand Grippers and CRL^™ Manipulators and Transfer Ports. DESTACO is based in Auburn Hills, MI, and operates globally through approximately 800 employees across 13 locations. More information is available at destaco.com and dovercorporation.com.

New entry-level rotary module for semiconductor and electronics from ETEL

March 7, 2017 By Miles Budimir Leave a Comment

ETEL’s new DXR+ is the newest member of its direct drive rotary module portfolio. For years, ETEL has offered a DXR rotary table as an accessory to its motion stages and now, with important design changes, the DXR+ is available as a stand-alone entry level rotary module featuring a compact design, light mass, and large hollow shaft which provides the right performance-to-cost ratio for mid-end applications in semiconductor and electronics.

The DXR+ has the exact same physical characteristics as its predecessor, the DXR, but brings major improvements in terms of stiffness which has a direct impact on the control bandwidth of any XY stage that is supporting it.

The new DXR+ sports a toothless ring design, similar to an ironless linear motor but in a rotary shape, ensuring zero-cogging along with cross-roller bearings providing high moment load capacity and high stiffness. It’s equipped with a Numerik Jena RIK4 encoder with 18,000 lines per revolution that can be read as either 1 VPP or a TTL signal output.

It’s designed for electronic and semiconductor applications that can benefit from bi-directionnel repeatability of ± 2 arc sec, position accuracy down to ± 3 arc sec after calibration, and position stability ± 0.2 arc sec.

Like any other standard modules from ETEL (ZT, Z3TH, RTTB), the DXR+ can be mounted on any standard XY platforms. The DXR+ is a one-degree-of-freedom module allowing unlimited angular travel. Nevertheless, as an option, travel can be limited to angular segments that are multiple of around 60°. The cleanliness level of a DXR+ ranges from ISO 5 down to ISO 1 under specific conditions.

For more information, visit www.etelusa.com.

ETEL S.A. is based in Switzerland with exclusive North American distribution through HEIDENHAIN CORPORATION in Schaumburg, IL. As a leading international supplier of direct drive and motion control components and integrated systems, ETEL supports high tech industry with linear motors, torque motors, positioning stages, and motion controllers/systems.

Highest-speed direct-drive rotary stage on the market from IntelLiDrives

February 21, 2017 By Lisa Eitel Leave a Comment

The ACR-32UT precision rotation stage is the lowest profile rotary stage with high-speed direct-drive rotary servo motor on the market.

A center aperture and lightweight construction makes this rotary stage suitable for semiconductor manufacturing and general automation applications.

High precision from a rotary stage with high dynamics

The ACR-32UUT has very wide dynamic speed range and can move at sub-rpm speed with low velocity ripple and accelerate quickly to 2,000 rpm. This stage can be easily installed into IntelLiDrives low profile open frame XY tables with a minimal stack-up height to minimize Abbe error.

Stage has multi-axis configuration

These features make the ACR-32UT outperform the stability, acceleration and settling speed of traditional servo motor gear-driven mechanisms. As an aside, IntelLiDrives offers myriad servo amplifiers and advanced controllers to provide a complete, integrated package.

Direct-drive rotary servo tables from IntelLiDrives feature IP-rated ingress protection

January 11, 2017 By Lisa Eitel Leave a Comment

Rotary tables with a high IP rating resist ingress of water and external particles — and the IP65 rating of rotary servo tables from IntelLiDrives assures against ingress of dust and small water jets. IP66 rating assures, in addition to IP65, against ingress of powerful water jets. IP67 rating assures (in addition to IP66-level protection) resistance to water penetration under heavy water jets and when partially submerged. More after the jump.

Rotary servo tables use direct-drive technology

Direct-drive rotary servo tables provide superior angular positioning and eliminate backlash, friction and wear problems associated with worm, gear and belt drives. Low maintenance and high throughput characteristics of the DDR stages yields the lowest total cost of ownership.

These rotary tables use direct-drive three phase brushless motor technology. There are no brushes to replace and no gear trains or belts to maintain.

Rotary servo tables use absolute encoder

Accurate positioning is assured with a precision encoder that provides arc-sec positioning resolution. The motor and rotary encoders are directly coupled to eliminate coupling backlash. The absolute encoder keeps track of its position always, and provides feedback as soon as power is applied. This feature is particularly useful in applications where the equipment has power turned off between uses. No need to move to home sensor or index pulse to establish a reference position. Ask the manufacturer for more information on the rotary servo tables through the portal at intellidrives.com/product/request.