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Bottom tapped rails available for quick ship

Bottom tapped rails are useful for mounting from the bottom of a base, as well as when contamination protection is required -- eliminating the need for bolt-hole caps. See the available models from THK, including standard and radial LM guides and standard and radial caged ball. All units are available for quick shipping.
Learn more.

Hybrid actuation system reduces energy consumption, simplifies designs

Learn how a leading manufacturer of household cleaning products solved its downtime problems due to an overloaded ball screw in its production-line electromechanical automated plastic cap dumping function. A Hybrid Actuation System (HAS) did the trick, combining the controllability of traditional electromechanical actuators with the power density, longer life, and failsafe conditions commonly found on traditional hydraulic systems.
Read this informative Parker blog.

Machine tending solution now compatible with any CNC machine

The Robotiq Machine Tending Solution has made automation accessible to businesses of all sizes, overturning the belief that automation is too complicated. The company says their part-feeding solutions can provide up to a 30% production runtime increase -- without communication cards, expensive wiring, custom programming, or permanent modifications.
Learn how to boost your CNC productivity.

How to implement redundancy in stepper motors

Some of the recent research activities in the area of electric motor drives for safety-critical applications (such as aerospace and nuclear power plants) are focused on looking at various fault-tolerant motor and drive topologies. After discussing different solutions, this article focuses on a miniature permanent magnet (PM) stepper motor design that provides increased redundancy.
Read this informative Faulhaber article.

Why choose electric for linear actuators? When precision, multiple positions, repeatability, or position feedback is important

Tolomatic has been delivering a new type of linear motion technology that is giving hydraulics a run for its money. Learn the benefits of electric linear motion systems, the iceberg principle showing total cost of ownership, critical parameters of sizing, and conversion tips.
Read this informative e-book. (No registration required)

New mini gearhead for robotics, semiconductor fab

Harmonic Drive is proud to announce the release of its CSF-2XH mini gearhead designed for servo and stepper motors. Available with an output shaft or flange, these gearheads are offered in four sizes with gear ratios of 30:1 to 100:1 and peak torque of .5 to 28 Nm. These mini strain wave gears are ideal for applications such as semiconductor manufacturing and robotics. Available through Electromate.
Learn more.

Super cool and versatile palletizing gripper: OnRobot 2FGP20

Palletizing just got easier and more affordable with the 2FGP20 from OnRobot, an off-the-shelf electric gripper with a payload of up to 20kg and endless customization possibilities to fit any automation needs. The 2FGP20 is an ideal solution that can be deployed and redeployed for multiple processes and handling different parts.
Learn more about the 2FGP20.
Learn more about palletizing.

New linear stages for increased load, speed, stroke

Discover the enhanced possibilities with Tolomatic's new size TRS 225 twin profile rail stage, offering expanded capabilities for precise and powerful linear motion in a closed-package design. This unit is built from the ground up to be highly rigid and accurate and is now available with strokes up to 86.6 in., travel speeds up to 50 in./sec, and load-carrying capacities up to 4,320 lb. Perfect for your heavy-duty needs.
Learn more.

Are ball splines right for your application?

Thomson Industries says ball splines are making a comeback, because more opportunities for automation bring more axes of motion to machinery, and pre-packaged solutions may not have the flexibility you require. But are ball splines the right choice for your design needs? They have the unique capability of integrating rotary and linear motion on a single shaft.
Read the Thomson technical article.

New stainless steel AC inverter-duty gearmotors meet IP-69K

Bodine Electric Co. has introduced six new type 56R1-50JW/H hollow shaft gearmotors that combine a stainless-steel AC inverter-duty, 230/460 VAC motor with a stainless-steel hollow shaft gearhead. When used with an AC inverter (VFD) control, these gearmotors deliver variable speed and maintenance-free operation over a wide speed range. Ideal for equipment subject to intensive cleaning, such as food and beverage, pharmaceuticals, and permanently wet environments.
Learn more.

Extend your range of motion: Controllers for mini motors

FAULHABER has added another extremely compact Motion Controller without housing to its product range. The new MC3603 controller is ideal for integration in equipment manufacturing and medical tech applications. With 36 V and 3 A (peak current 9 A), it covers the power range up to 100 W and is suitable for DC motors with encoder, brushless drives, or linear motors.
Learn more.

Motion systems: Check out THK's new online store!

THK has launched a new online store that is chock full of your motion system needs. Check out their latest offerings for Linear Motion Products (guides, actuators, rails, splines, and rollers), Feed Screw Products (ball and lead screws), Rotation Products (cross roller rings and cam and roller followers), Oscillation Products (link balls, rod ends, spherical bearings), and more. Lubrication Products available too.
See the new THK store.

Advantages of slotless motors over standard stepper motors

According to Lin Engineering, "Slotless motors have gone through innovations in design as well as manufacturing, making them a good choice for specific applications." This article explores the benefits and drawbacks of slotless motors and provides information that may help you decide when to -- and when not to -- select them as a solution.
Read the full article.

Intro to motor constants for fractional horsepower gearmotors

According to motor expert Bodine Electric, "Motor constants are needed to calculate permanent magnet DC (PMDC) or brushless DC (BLDC or EC) motor specifications and ratings, or to match the motor properly to an amplifier." You need the constants to predict the motor's performance with changing variables, such as different input voltages or different loads. This app note explains what the constants are, how they are derived. and how to use them. Very useful.
Read this informative Bodine Electric blog.

New wheel hub gearbox for AGVs and AMRs

Drive your automated guided vehicles (AGVs) and autonomous mobile robots (AMRs) with the GAM GML Wheel Drive Gearbox. GAM's GML Series Wheel Drive Gear Reducer uses planetary gearing for a coaxial system. The motor mounts directly behind the wheel without axle offset for an inline drive from wheel to motor. Features a compact design with short overall length.
Learn more.

Study finds a way to prevent fires in next-generation lithium batteries

In a study that could improve the safety of next-generation batteries, researchers discovered that adding two chemicals to the electrolyte of a lithium metal battery prevents the formation of dendrites -- "fingers" of lithium that pierce the barrier between the battery's halves, causing it to short out, overheat, and sometimes burst into flame.

Dendrites (fingerlike deposits of lithium metal) grow from the surface of a battery anode and penetrate the separator between the battery's halves. When this happens the battery can short-circuit, overheat, and burst into flame.

 

 

 

 

The findings, published June 17 in Nature Communications, could help remove a major barrier to developing lithium-sulfur and lithium-air batteries, promising future technologies that could store up to 10 times more energy per weight than batteries now used in consumer electronics and electric cars.

"Because these batteries would be much lighter than today's rechargeable batteries, they have a lot of potential for extended-range electric vehicles," said Yi Cui, an associate professor at Stanford University and the Department of Energy's SLAC National Accelerator Laboratory. "But one of the things that's been holding them back is their tendency to form dendrites, which are also the culprit behind overheating and occasional fires in today's lithium-ion batteries."

A new approach to safety
Dendrites form when a battery electrode degrades, and metal ions become deposited on the electrode's surface. When those finger-like deposits elongate until they penetrate the barrier between the two halves of the battery, they can cause electrical shorts, overheating, and fires.

In a previous study published last October, Cui and his colleagues reported that they had developed a "smart" lithium-ion battery that senses when dendrites start to puncture the barrier so the battery can be replaced before the situation becomes dangerous. This could offer a solution for millions of batteries now in use in cell phones, laptops, and other devices, as well as in electric cars and airplanes.

The new research addresses battery technologies that haven't reached the market yet, and it takes a different approach: adding chemicals to the electrolyte to prevent dendrite formation. One compound, lithium nitrate, has been under investigation for a long time as an additive to improve battery performance. The other, lithium polysulfide, has been considered a nuisance: Formed when a sulfur electrode degrades, it travels to the lithium metal electrode and wrecks it, Cui said.

In brainstorming sessions, the research team realized their combined effect had not been studied before; together the chemicals could potentially react with lithium metal to form a stable, solid interface between the electrode and the electrolyte.

Improved performance
They assembled coin cell batteries, similar to the ones that power calculators, remote controls ,and watches, and added various concentrations of the two chemicals to the ether-based electrolyte. Then they ran those batteries through many charge/discharge cycles, took them apart, and examined the electrodes with an electron microscope and an X-ray technique that reveals their morphology and chemical composition.

They found that adding both chemicals in just the right amounts stopped lithium dendrite formation; harmless pancake-like deposits grew there instead. The lithium metal acquired a stable coating that helped protect it from further degradation and actually improved the battery's performance.

Images from a scanning electron microscope show the surfaces of battery anodes after 100 charging cycles. Adding a combination of two chemicals suppresses dendrite growth (top); when only one of the chemicals, lithium nitrate, is added, dendrites cover the surface (bottom).

 

 

 

 

In tests, batteries with both chemicals added operated at 99 percent efficiency after more than 300 charge-discharge cycles, compared to significantly decreased efficiency after 150 cycles for batteries treated with lithium nitrate alone, said Fiona (Weiyang) Li, a postdoctoral researcher in Cui's lab and first author of the paper.

Harnessing synergy
"This is a really exciting observation," Li said. "We had been doing experiments all along with these two chemicals in there, but this was the first time we looked at the synergistic effect. This does not completely solve all the problems associated with lithium metal batteries, but it's an important step."

Yet-Ming Chiang, a professor at the Massachusetts Institute of Technology, collaborated with the team and helped them interpret their results. He said the next step is to see if this approach can prevent dendrite formation in larger-scale cells that are closer to being practical batteries. It may also work for electrodes made of other metals, such as magnesium, calcium, or aluminum, that also have potential for storing much more energy than today's batteries.

"Preventing dendrite formation is going to be key to their success," Chiang said.

Funding for the project was provided by the Joint Center for Energy Storage Research, a Department of Energy Innovation Hub, and Cui and Chiang are both JCESR principal investigators.

Source: SLAC National Accelerator Laboratory (operated by Stanford University for the U.S. Department of Energy Office of Science and located in Menlo Park, CA)

Published August 2015

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