Linear Encoder provides true straight-line positioning.

Press Release Summary:

ScrewCoder combines lead-screw assembly with linear encoder. Because nut and screw are integral parts of measuring components, it provides straight-line linear measurement of axis with ±10 micron accuracy. Accuracy is not influenced by screw pitch or reversal errors. System does not require recalibration due to screw wear and it will not misread due to geometric errors such as pitch, roll, and yaw of machine. IP67-rated unit resists shock and vibration.

Original Press Release:

Newall Introduces Screwcoder

COLUMBUS, Ohio (August 2002) A revolutionary concept in linear measurement, the ScrewCoder, will be announced by Newall Electronics, Inc. at the 2002 International Machine Tool Show in Chicago.

Newall's ScrewCoder is an industry first as it combines a lead screw assembly with a linear encoder. True straight-line positioning is now possible as the nut and screw are integral parts of the measuring components.

As opposed to the traditional separate lead screw and rotary encoder assembly, the accuracy of the ScrewCoder is not influenced by screw pitch or reversal errors. This is due to the fact that the nut is the actual reader head and the lead screw is the actual scale. This provides for true straight-line linear measurement of the axis that is generated from a rotary movement. In addition, the system does not require period recalibration due to screw wear and it will not misread due to geometric errors such as pitch, roll and yaw of the machine.

Principle of Operation

The ScrewCoder is based on Newall's Spherosyn® technology which operates on the principle of induction. A drive coil contained within the nut generates an electromagnetic field. This field interacts with high precision steel balls that are contained in the screw. A set of pickup coils detect the variations of the induced field, which are then combined and processed to generate signals that vary in sine and cosine form caused by axial (not rotary) movement along the scale. The degree of phase shift between 0° and 360° is related to the position of the nut over a ball.

A high-speed Digital-Signal-Processor (DSP) samples the signals and converts them from their natural analogue state to an industry standard differential quadrature at TTL levels. The DSP also synchronizes the periodic reference marker pulse to the A and B High output Levels.

The ScrewCoder offers accuracy to +/-10 micron, includes the performance benefits of an IP67 rating, and is highly shock and vibration resistant.

About Newall Electronics, Inc.

As the leader in digital readout systems and Linear measurement technology, Newall differentiates itself from the competition by offering strong warranties and solid products designed to withstand harsh environmental conditions. Newall's DRO systems and the patented Spherosyn® and Microsyn® Linear Feedback Transducers are recognized throughout the world for quality and reliability. Its products are manufactured in Europe and sold through over 300 authorized industrial distributors in the U.S. with worldwide distribution in 63 countries.

Newall Electronics, Inc. is based in Columbus, Ohio, and was established in 1989 as a wholly owned subsidiary of Newall Measurement, Ltd. of Leicester, England. The company's products can be installed to support a variety of linear measurement applications including milling, boring, turning and grinding both for manual and computer controlled situations. For more information on Newall Electronics or its products, customers may call 800.229.4376, or visit the company's website at

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