New integrated actuator eliminates the need for a systems approach to linear actuation

Citation

(2001), "New integrated actuator eliminates the need for a systems approach to linear actuation", Assembly Automation, Vol. 21 No. 2. https://doi.org/10.1108/aa.2001.03321bad.001

New integrated actuator eliminates the need for a systems approach to linear actuation

New integrated actuator eliminates the need for a systems approach to linear actuation

Keywords INMOCO, Actuators, Automation

The new GS40 linear actuator from INMOCO combines a brushless servomotor, an inverted roller screw and an encoder/resolver feedback source into a single compact assembly. This arrangement is said to eliminate the cost and complexity of a systems engineering approach, as all elements for producing linear motion have been properly matched and designed into the actuator and tested for their efficiency.

The GS40 (Plate 1) is the latest introduction to INMOCO's GS series of inverted roller screw actuators. A 99mm frame size unit, the GS40 offers users a range of strokes from 152mm to 457mm, continuous force ratings up to 5,337N, and linear velocities up to 635mm/second. These performance figures place the GS40 in the medium range of the GS series overall. At the top end of the range the GS60 (178mm frame unit) is capable of providing continuous thrust ratings up to a maximum of 35,600N and speeds of over 1m/second.

Plate 1 New GS40 integrated actuator from INMOCO

The brushless servo design of the GS series linear actuators allows them to be used in state-of-the art closed loop servo systems, where electronic control of positioning and velocity is required. In these systems position feedback can be provided in a number of different forms to match customer specifications, including resolvers, encoders or internally mounted linear position feedback sensors.

The GS series actuators employ an inverted roller screw mechanism to convert the rotary motion of the brushless motor into high speed, high thrust linear motion. This mechanism has a lead accuracy of 25m/300mm for high precision operation and can also be supplied with zero backlash.

According to INMOCO, the large contact area of the roller screw – due to rollers rather than balls – allows high force characteristics while guaranteeing long life – 15 times the life of comparably sized ball screws is common – even in the most demanding repetitive applications. In addition, the planetary design of the roller screw allows it to be accelerated and rotated faster (up to 5,000rpm) than comparably sized ball screws.

GS series actuators offer additional benefits in the form of contamination protection. In conventional rotary to linear devices the critical mechanisms are exposed to the environment and therefore require frequent inspection, cleaning and lubrication. In contrast, all converting components in the GS series actuator are mounted within the sealed motor housing which is IP65 rated (IP67 upon request). The smooth extending rod allows the use of a bushing and seal arrangement, which prevents abrasive particles and other forms of contamination from entering the actuator's critical mechanisms. This is said to ensure trouble-free operation even in the most severe environments.

Lubrication requirements for the GS series actuators are minimal. Designed to be lubricated with either grease or re-circulated oil, they can reportedly be run for up to 10,000 hours between re-greasings. Re-circulated oil lubrication eliminates the need for lubrication maintenance altogether: an oil lubricated GS actuator, say INMOCO, will operate indefinitely with no servicing requirements.

The GS actuators are available in a wide variety of stroke lengths, sizes, speeds and mounting configurations. INMOCO can also supply custom actuators to fit special applications. The capabilities of the GS range are extended by a wide range of optional features including internal end switches, electric brakes, linear positioning sensors, backlash-free followers and multiple mounting and rod end configurations.

GS actuators are suitable for use in many demanding applications including wire guiding, chip and wafer handling, robot manipulation, testing, web guidance, indexing, material cutting and tension control.

For further information contact: Gerard Bush, Sales Application Engineer, INMOCO Limited, 4 Brunel Close, Drayton Fields, Daventry NN11 5RB, UK. Tel: +44 (0)1327 300320; Fax: +44 (0)1327 300319; e-mail: GerardB@inmoco.co.uk