Tubular linear motors have numerous advantages due to their intelligent design

By OEM Update Editorial August 8, 2022 3:42 pm

Growth in the global linear market is being driven by both increased demand across key industries and the clear advantages of linear motors over conventional motors. Within this segment, the contribution of ANCA Motion’s LinX® M-Series linear motor has expanded the market and stands out above ball screw and flatbed motor options due to a number of design intricacies that simplify installation and use and push quality performance even further. Designed for function, the tubular construction of the LinX® has several key benefits over flat linear motors.

Easy to install and retrofit

Simplicity is a key element of any great design and whether new or retrofitted, tubular linear motors are simple to install. Robust and thermally efficient they provide drop-in replacements for ball screw and pneumatic cylinders.

As an ideal replacement to retrofit pneumatic cylinders, the LinX® M-series motors are optimised to ensure the minimum effort and impact to end customers. A key feature is that mechanically the motor is designed to be fully compatible with standard pneumatics accessories, such as mounting plates, linear guides and coupling pieces. For retrofit projects, this means the LinX® M-series motors can be easily integrated, while for new machines this allows machine builders access to a wide range of standard accessories. Effortless retrofits contrast with the technical challenges usually presented when retrofitting traditional pneumatics with flatbed linear motors.

Precision and thermal stability

Going from flatbed to tubular actuation significantly improves thermal stability. With less expansion, components and the overall system perform with higher accuracy. The LinX® M-Series linear motor also offers high levels of positional accuracy, with 10 micrometre resolution based on an integrated position sensor. With the M-Series, explains Product Manager Heng Luo, “Because the motor is floating in the machine structure, that enables us to put a water-cooling jacket around the motor and completely take the heat out of the motor.”

“That’s a vast advantage from a thermal perspective compared to a flatbed.”

Given the trend for increasing automation in motion control technology, the requirement for positioning accuracy is essential.

Energy efficient

Both the economic and environmental impacts of energy efficiency in machinery continue to increase in importance. Energy efficiency should be designed into a machine or component to best harness the benefits. With LinX® motor’s tubular structure design, the magnetic flux, generated by the permanent magnets contained in a stainless steel shaft, can be fully utilized by a forcer which covers the full shaft surface. This design enables the optimal energy efficiency.

Designed for low maintenance

Machines with flatbed linear motors typically require a separate chiller for thermal stability, and the attractive force between coil and magnet bed creates tremendous downforces on the bearings, making everything wear faster, decreasing efficiency. In addition, flatbed-style linear motors typically have a back-iron in their magnetic circuit which further increases the downforces and creates cogging. ANCA Motion’s LinX® motor consists of a shaft containing magnets and a forcer containing wound copper coils. The symmetric design results in zero attractive forces between the forcer and shaft, greatly reducing the loading requirement on support bearings.

The thermal barrier design separates and removes heat from the motor, eradicating thermal growth for the machine. With LinX®’s simple construction, non-critical air gap and lack of physical contact between shaft and forcer, machine manufacturers can greatly simplify installation, reduce maintenance and extend machine life.

Ingress protection (IP) for harsh environments

The absence of direct contact between parts and no need for rail tracks means no need for lubricants, which can risk contamination. Flatbed motors can be challenging to seal and protect, but tubular motors provide a superior level of protection from material ingress, as well as increased safety levels for the operator. The LinX® M-Series’ magnets are also sealed in a stainless-steel tube, with an IP66 rating achieved.

Options such as the LinX® M-Series are growing in popularity in food and beverage, pharmaceutical and other applications where hygiene is important.

Compact design

A compact footprint is another benefit of tubular designs when compared to flat linear motors. The design also provides the option to move with either the forcer in motion and the thrust rod stationary, or vice versa.

The option for the thrust rod to be in motion is one factor making tubular linear motors an ideal replacement for pneumatic cylinders. Along with more speed and higher accuracy the benefits of a tubular linear design are being adopted across multiple industries.

A heritage of innovation at ANCA Motion

ANCA Motion’s linear motors were originally developed for sister company ANCA CNC Machines’ FX Linear and MX Linear machines. ANCA is a leader in CNC tool grinding technology, with a series of world firsts since beginning in 1974. The LinX® M-Series has been developed within a culture of world-class engineering, developing machine tools where micron-level precision is treasured. An international network of 125 engineers in strategic locations is on hand, offering fast, reliable support.