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AMO Corporation’s new IP67-Rated LMB-410 Spar Linear Encoder

AMO Corporation (www.amo-inc.com) is proud to announce the release of the new IP67-rated LMB-410 Spar Linear Encoder, which will be spotlighted at the 2010 International Manufacturing Technology Show (IMTS) at McCormick Place, Chicago on September 13 to 18. The company’s stall will be found in Booth #E-5220 inside the Quality Assurance Pavilion located in the Lakeside Center (East) Building.

The new LMB-410 offers robust measuring/position feedback with IP-67 rating and performance similar to a linear optical encoder. The LMB-410, operating on an inductive scanning principle, is best suited for general purpose machines, such as medical equipment, printing equipment, machine tools and military/aerospace applications. Its IP67 rating makes the machine ideal for dirty or contaminated conditions including being fluid submersible.

Its adhesive-free mounting spar with a snap cover eliminates concerns related to adhesive-backed spars becoming loose in oily environments. Its encoder head is equipped with wipers to automatically clean spar scale during operation. The encoder head’s gain compensation and auto offset eliminate the need to use a test box during setup.

The LMB-410 is rated for operation that ranges from -40 to +120°C for any measuring length ± 5 micron/m linearity. The new encoder also meets high-shock, high-speed and vibration specifications.

Renishaw Helps Achieve High Accuracy Grinding for Giant Wind Turbine Bearings

KMT Lidköping (www.kmtgroup.com/lidkoping/) has unveiled its new hard-turning VTG4000 (Vertical Turning Grinding) machine that uses a combination of Renishaw SiGNUM optical angle and linear encoders to achieve the required accuracy, and Renishaw magnetic encoders placed on the exposed axes of the cutting heads.

“Our largest machine used to accommodate parts up to 600 mm diameter, but the VTG4000 can handle diameters in excess of 4000 mm, the size of the largest wind turbine bearings. This is hard turning and grinding which can be very demanding, and the positioning accuracy is very important, with a direct effect on the quality of the finished bearings. A standard size machine, using ballscrews on the axes, will manage to maintain a 3 µm form deviation, yet despite the considerable difference in relative size, the VTG4000 has been proven to achieve an exceptional form deviation of less than 1 µm, with feed resolution in 0.1 µm steps,” said Eive Johansson, Lidköping’s VTG Chief Designer.

“At the heart of a Lidköping machine are the linear slides. The combination of hydrostatic guideways, air seals and linear motors create a stiff, accurate and maintenance-free system. To achieve dynamic stiffness we need high gain and the gain is linked to the quality of the encoder scales. It also makes a big difference that the angle encoders have the scale integrated directly onto the ring,” he added.

Mr. Johansson first saw the Renishaw SiGNUM encoders during the EMO 2007 exhibition in Hannover, and then followed a period of rigorous testing by the company. As he explained: “The choice of Renishaw was easy; we compared different scales assembled on our reference slide and bought the one with the best performance. It was important that the linear encoders could be supplied in a continuous length of at least 4.5 m and SiGNUM is the easiest way to achieve this. The Renishaw encoders also give more resistance to dirt. We have now fitted Renishaw encoders to all four linear slides and as expected, we have had no problems!”

“The rotary table has the same design principle, with hydrostatic radial and axial bearings, air seals and torque motors for the drive. The same analysis was done, and the Renishaw SiGNUM angle encoders were chosen,” he added.

The Renishaw encoders have an integral patented set-up LED that speeds installation and eliminates the need for separate set-up equipment/complex external, or oscilloscopes.

“One of the best features of the Renishaw encoders is how easy they are to set-up,” Mr. Johansson said. “With the scale attached and the readhead approximately located the indicator lights make it very easy to see how well the two elements are aligned and then make the final adjustments.”

FASTRACK Linear Encoder System from Renishaw

Renishaw’s new FASTRACK linear encoder scale system brings high accuracy, stainless steel construction and quick, easy installation to large, sectional machines used in flat-panel display and photovoltaic manufacturing applications, as well as large CMMs that require removal of the scale for transit. Also ideal for linear motors with aluminum substrates, and applications where thermal expansion of the scale must be independent of the machine structure, or those involving dissimilar axis materials, the track-mounted scale can run across gaps up to 25 mm wide, while providing ± 5 µm/m accuracy.

The FASTRACK system consists of two miniature guide rails that secure low-profile scales (8 x 0.2 mm cross-section) while allowing them to freely expand at their own thermal expansion rate with almost zero hysteresis. The scale can be installed, removed and reinstalled as many times as required, and damaged scales can be pulled out of the guide rails and quickly replaced, even where access is limited, reducing machine downtime.

FASTRACK is available on reels for cut-to-length flexibility at the point of installation, allowing machine builders to minimize stock and lead-times. Generous tolerance makes measuring and cutting quick and easy. Easily installed, the self-adhesive guide rails feature integral pre-aligned sacrificial spacers which are removed after the rails are fitted to the axis. The scale is then fed in from either end and locked to the substrate at a single datum point anywhere along the axis using cyanoacrylate glue or a clamp.

Part of a modular solution, FASTRACK can be used with either the RTLC stainless steel incremental scale and super-compact TONiC readhead, or Renishaw’s new RESOLUTE linear absolute encoder and RTLA absolute scale. The encoders in both set-ups feature advanced optoelectronics with resolutions to 1 nm, low sub-divisional error (SDE) and very low jitter for smooth velocity control and rock-solid positional stability. For TONiC RTLC incremental scale installations, limit magnets and a reference mark selector are fitted to the FASTRACK and secured with a bolted clamp rather than using glue. The RTLC scale features multiple INTRAC reference marks at regular spacing.

The FASTRACK system is backed by Renishaw’s global sales and support network and, like the TONiC and RESOLUTE encoder systems, it is compliant with the WEEE and RoHS environmental standards.

Renishaw
www.renishaw.com/encoders

SICK STEGMANN Introduces TTK70 Motor Feedback System

DAYTON, OH – SICK STEGMANN, INC. introduces the TTK70 Motor Feedback System.  The TTK70 is an absolute, non-contact linear measuring system that delivers measuring lengths up to 4,000 mm, resolution of <1 μm and system accuracy of <10 μm, at operating speeds up to 10 m/s.  The result is precise and highly reliable absolute position determination for linear motors in a diverse range of applications.  The TTK70 motor feedback system is rated for operation in temperatures ranging from -30…+85°C.  It carries the CE mark and is RoHS compliant.

The TTK70 consists of a read head and a magnetic tape featuring a magnetic code that forms the measuring scale – 10 mm wide, and up to 4,000 mm long.  The code consists of an incremental and an absolute track (twin-track tape).  Absolute position values are calculated by the read head first detecting the absolute starting position during start-up of the linear motor.  All further positions of the drive are determined via the incremental position on the magnetic track, i.e. sine/cosine signals.  The values are transmitted via the HIPERFACE® interface to the evaluation electronics of the linear drive – a market-standard method of communication that, for the first time ever via the TTK70, is now available for linear measuring systems.  The result is an interface standard for all common servo drives, that covers all applications, with only one signal type.

The robust metal housing of the read head offers IP65 protection, has two mounting holes designed for high tightening torques and, even with the plug connection, is hardly bigger than a matchbox – making it the smallest system of its kind.  Inside, the TTK70 features the latest in sensor and evaluation technology.  The sensor PCB, which is aligned with the measuring plane, is equipped with Hall sensors on two parallel tracks.  When installed their placement coincides with the position of an incremental and an absolute track on the magnetic tape.

SICK-STEGMANN is currently the only supplier worldwide that is able to offer to drive manufacturers both rotary and linear motor feedback systems with an integrated HIPERFACE® interface, popular in applications such as erosion machines, handling systems in semiconductor production, automatic assembly and placement machines, vertical lifting systems, pick and place applications in electronic production, or the food industry.

SICK STEGMANN, INC.
www.stegmann.com

Kübler by TURCK Magnetic Linear Encoders

Minneapolis, MN — TURCK introduces a new line of Kübler by TURCK robust magnetic linear encoders. Utilizing A and B output voltage channels plus a periodic index with the corresponding inverted channels, these encoders achieve high accuracy in a broad range of linear motion applications. The T8.LI20 and T8.LI50 linear encoders are available with either a push-pull output or an RS422 interface and provide a voltage range from 4.8 to 30 VDC.

The linear encoders are used with magnetic bands that are attached to the mounting surface and protected by a stainless-steel cover. The encoder’s resolution is up to 5 µm with quadruple evaluation, and its repeat accuracy is +/- one increment with a measuring speed up to 82 feet per second, depending on the resolution.

Kübler by TURCK encoders use non-contact technology and can survive environments with high vibration (30g/10-2,000 Hz) and shock (500 g’s/1ms). The products can also be used outdoors, due to an IP 67 protection rating, wide temperature range and the weatherproof die-cast housing. The metal housing also offers improved shielding against electromagnetic interference.

A built-in LED provides a warning signal or an index pulse, allowing for simple set-up and diagnostics. Connections are made via a high-grade shielded PUR cable that is also suitable for cable track installations.

TURCK
www.turck.us

Micropulse Generation 7 Linear Position Transducers from Balluff

Florence, KY – Balluff has introduced the first of its new Micropulse Generation 7 linear position transducers, featuring improved measurement and environmental specifications, longer lengths, and more flexible setup than previous models. Debuting in the analog rod style housing, Generation 7 is available in two versions, Micropulse and Micropulse Plus. Micropulse is fully backward compatible with Balluff’s Generation 5 products, yet delivers better measurement performance and environmental ratings. The advanced version Micropulse Plus features flexible output scaling and configuration using a PC interface.

Performance improvements include stroke lengths to 300 in. with the maximum non-linearity cut in half. This features ±50 µm for nominal strokes less than 500mm,  ±0.01% of full scale for 500 to 5500mm, and ±0.02% of full scale from 5501mm to 7600mm. Shock ratings are to 150g and vibration rating to 20g. EMC severity for static, RF, burst, and line noise is Level 3; for surge, Level 2 and magnetic field immunity to Level 4. Additionally, housing protection is to IP68 for pre-wired cables and IP67 for connector models.

Other improvements allow easier and more flexible configuration options during setup. Dual bi-color LEDs handle double duty for diagnostics and as a setup aid for pushbutton scaling of the position outputs. Communicating to a PC over standard USB, Micropulse Plus outputs can be scaled, inverted, and configured for single- or two-magnet position, velocity, or differential position between two magnets. Intuitive software features a simple-to-use graphical interface that allows drag-and-drop adjustment of the output characteristics. Configuration files can be saved for backup, replication, or for emailing to remote locations. Manual adjustment without a PC is also possible using the included pushbutton tool and simplified setup procedure that minimizes button-pushing complexity while maximizing operational flexibility.
For more information, visit:  http://www.balluff.com/btl7-z

www.balluff.com

IP69K Linear Position Transducer for Harsh Applications from Balluff

Florence, KY – Balluff’s new Micropulse® ProCompact linear position transducer for demanding linear feedback applications is rugged, accurate, and protected against environmental hazards such as high humidity, ambient temperature variations, high-pressure wash down, and exposure to caustic chemicals.

The Micropulse ProCompact rod-style transducer incorporates field-proven, non-contact magnetostrictive technology into a welded, hermetically sealed stainless steel housing providing superior long-term reliability and service life compared to competing contact-based sensors such as linear or rotary potentiometers.

The ProCompact is ideal for the following types of applications: hydropower and other wet applications, railroad maintenance equipment, steel production, sawmill applications, or any other application involving high humidity, ambient temperature variations, and high-pressure wash down.

The Micropulse ProCompact linear position transducer comes in standard ¾-in.-16 UNF (optional M18 x 1.5) mounting threads, allowing the transducer to be installed into hydraulic or pneumatic cylinders. Right out of the box, the ProCompact is environmentally protected to IP68. For even more demanding applications, the threaded fitting on the ProCompact housing can accommodate a cable protection system, offering environmental protection up to IP69K.
For more information, visit www.balluff.com/procompact

Linear Cable Transducer from BEI Industrial Encoders

BEI Industrial Encoders’ new linear cable transducer provides digital position and speed feedback information in a rugged, easy-to-install package. Model LT25 cable transducer utilizes a flexible measuring cable mounted to an internal spring-loaded spool and a quadrature encoder output to precisely measure linear motion applications. The sturdy cable is made of nylon coated stainless steel for ultimate strength and has a measurement range up to 125 inches.

Easy to install, simply connect the LT25 cable to your moving equipment and secure the base to a fixed object. Hard to reach areas or worries about shaft misalignment are now not a problem. The LT25 cable transducer allows for easy reorientation of the mounting bracket or encoder connector position, giving users added adaptability to their installation. With an IP66 rating, the LT25 is a perfect solution for a variety of industrial measurement challenges including wet, dirty, or outdoor environments or applications where your measuring range travels over a harsh environment.
For more information, visit www.beiied.com/cable-transducer

IP67-rated Magnetic Rotary Encoders for Heavy-Duty Applications

Southington, CT – For high resolution, high dynamic measurement of position, speed and velocity, Baumer has introduced the MHXX Series of hollow-shaft, large-bore, magnetic rotary encoders. These robust, non-contact encoders contain no bearings, so measurement is contact-free and components do not wear. The IP67 rated housing and fully encapsulated read head electronics allow long-term, reliable performance in high shock and vibration environments.

MHXX Series Magnetic Rotary Encoders operate efficiently in a wide range of temperatures, from -40 to 100ºC. All products in the line are compact, featuring very thin rotors and read heads that adapt easily to the axis of rotation. Specifically designed for use on shafts from 20 to 740 mm, the encoders are designed to allow large clearances between the rotor and the sensing head for easy mounting. The encoder’s disk may be mounted using set-crews, clamping rings, or clamping fixtures.

These IP67-rated encoders withstand vibration to 30g and shock to 300g. All encoders in the MHXX Series are available with incremental or sine-cosine outputs and certain models are also available with an additional absolute output track up to 17 bits. MH Series encoders offer large (+/- 3mm) permissible axial displacement and large (0.1 to 2.2mm) permissible air gap tolerance depending on size of bore.

MHXX Series Magnetic Rotary Encoders can be used on equipment and machinery used in motion control, textile production, wood/timber processing, packaging, machine tool, medical, electric motor and general industrial applications.

For more information contact Baumer at (800) 937-9336, or email at sales.us@baumergroup.com.

www.baumergroup.com/cameras

Pulsed-Inductive Sensor for Low-Cost Linear Position Feedback

Florence, KY – BIW Pulsed-Inductive sensors from Balluff only look like traditional resistive linear potentiometers. However, unlike linear potentiometers, BIW sensors use patented, non-contact technology to provide continuous, absolute, analog position feedback. Because there is no mechanical contact, wear is not an issue. BIW sensors are available at a price level equal to or lower than many linear potentiometers.

Like resistive linear potentiometers, BIW Pulsed-Inductive sensors are available with analog voltage outputs (-10 to +10V or 0 to +10V). But unlike linear potentiometers, these innovative linear position sensors are available with analog current outputs (0 to 20 mA or 4-20 mA) as well, without the need for external signal conditioning. This is important because analog current signals offer much better electrical noise immunity and allow for longer cable runs compared to analog voltage signals.

Balluff BIW Pulsed-Inductive linear position sensors are designed to be form-factor replacements for traditional resistive linear potentiometers, right down to the familiar sliding plunger. It also means BIW sensors are a perfect fit for linear feedback applications such as those found on plastic injection molding machinery, packaging machinery, hydraulic motion bases, and woodworking machinery. BIW sensors are also an ideal solution when low-cost, continuous position feedback is required on hydraulic or pneumatic cylinders.

For further information, visit: www.balluff.com/biw

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