There are two fundamental types of couplings; rigid and flexible. Rigid couplings are generally used in applications requiring precise alignment, whereas flexible couplings can be used where there is a slight amount of misalignment between shafts. So a flexible shaft coupling accommodates misalignment while still transmitting torque. Misalignments can be one of several fundamental types, including lateral, axial, angular, or skewed. The greater the misalignment the less efficient the motor is in generating speed and torque. And misalignment contributes to premature wear including broken shafts, failed bearings and excessive vibration.

Flexible couplings are typically the most compliant of components in mechanical motion systems, making torsional stiffness a critical factor in terms of maintaining positional control over a load.

Types of motion differ in applications as well. For instance, in manufacturing lines, motion may be either continuous or start and stop. With the latter type there is a lot of vibration generated and couplings can help dampen the vibrations and diminish the settling time of the system and improve throughput. In contrast, continuous motion applications give greater weight to torsional strength over damping capabilities. Motion applications that require precise motion control such as in packaging and scanning and inspection call for zero-backlash couplings.

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Bellows couplings are typically made from a stainless steel tube hydroformed to create deep corrugations that make them flexible across axial, angular, and parallel shaft misalignments. The bellows absorbs any slight misalignments between the mounting surfaces of two components.

When coupling shafts, bellows couplings absorb slight misalignments from perpendicularity and concentricity tolerances between the mounting surfaces of the two connected components. Bellows couplings tend to have the highest torsional stiffness of any servo motor coupling, and so are used in applications requiring high precision positioning.

Selecting the right bellows coupling for an application starts with knowing the torque involved. For instance, it’s helpful to know the peak torque capacity of the servo motor. This value, multiplied by the gear reduction ratio and a safety factor of 1.5, gives the minimal torque calculation.

In most cases, couplings are rated according to the maximum peak torque to be transmitted. The peak torque should not exceed the coupling’s rated torque. And by rated torque is meant the torque that is continuously transmittable within the specified acceptable speed and misalignment ranges.

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Sympatec’s particle measuring systems are specifically designed to detect particles in a nano range up to 10mm. The systems identify application in quality assurance in pharmaceutical manufacturing, cement production, coffee production and print toner manufacturing.

A representative sample is first taken from the production system before measurements can be made. The materials that will be tested are conveyed on air via a production process in pipes with 50mm-800mm inside diameter.

A SK5/10/F/XX type of R+W safety coupling was used in the drive mechanism of the sampling tube. The coupling has ATEX certification for zones 2/22 and 1/21. This is important because samples are taken in an ignitable dust or explosive atmosphere.

Aside from operating and installation instructions, a required declaration of conformity and ATEX certificate is enclosed with the R+W Safety Coupling when it is delivered.

Specified by the customer, the SK5 pluggable solution is necessary for certain industrial environments where a wide variety of products are often designed on the same equipment line.

The components utilized in processing the previous products must be cleaned when converting the line for the production of a different product. Removing components for cleaning is made easy with its plug-in capability.

Another problem at this stage is about the temperature range. The range of operating temperature specified for the coupling is up to 150ºC.

Since plastic plug-in segments are rated for use up to 120ºC, the material for the said parts was changed. Built similar to the plastic part, the new steel plug design can handle an extended temperature range.

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In order to achieve a 50% weight reduction target, R+W America entered a collaborative effort with local universities for two years, designing the product from the ground up instead of simply optimizing or redesigning existing products. This resulted in a torque limiter built from high-tech materials with innovative assembly technology and unique surface treatments, which simultaneously reduce its footprint and surpass weight reduction targets.

Aside from custom material specifications, some improvements to the ball detent’s configuration and specially designed spring systems, leading to a 40% increase in torque capacity, the weight reduction has been achieved by compressing individual components.

The four sizes (Series 30/60/150/300) involve several mounting options, which include direct and indirect drive versions, as well as cover disengagement torque values from 5Nm to 700Nm.

Models SLP (keyway) and SLN (clamping) attach by flange to sheaves, sprockets, gears and pulleys, as well as include an integral dual-bearing system to support chain and belt tension when properly placed over the shaft. Models SLE (servo insert coupling) and SL2 (bellows coupling) mount inline between the two independently supported shafts like motor to ball screw connections and compensate for the smaller yet inevitable misalignment, which is present in this kind of machine layout.

Each of the four types is field adjustable and comes with English and metric bores based on the customer’s specifications.

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The new rotary coupling provides support for all pneumatic and electrical requirements for high-speed spindles, with other models available to support either 4 or 2 spindles.

Built with IP67 rating, it uses positive air over-pressure to avoid any chip or coolant contamination, and the pneumatic supply in the coupling also supplies air-seal to the spindles. When mounted to CNC lathe turret face, the rotary coupling can rotate up to 500 RPM maximum speed. An anti-rotation shaft is integrated to prevent it from rotating as the turret spins.

The rotary coupling can be used with any Micro Line spindle developed by IBAG providing speed up to 100,000 RPM for small diameter drilling and micro-milling applications. Custom spindle mounting brackets, which are excellent for medical machining on Swiss-type, can be used to allow milling or cross-drilling at unique angles.

IBAG North America also offers fixed right-angle spindles and adjustable spindles in up to 25 mm diameters and up to 250 watts power.

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Schmidt Offset couplings provide the utmost in precision for parallel offset shafts. They transmit constant angular velocity and torque in a wide range of parallel shaft misalignments. With a time-proven design, they are used in a wide range of machine applications such as printing, embossing, paper converting, pharmaceutical, and automated assembly systems.

The new Schmidt sealed bearing coupling feature incorporates needle bearings with internal micro-poly lubrication. There are no lube fittings making for a cleaner coupling setup.

Compact in design, Schmidt Offset couplings with the new zero maintenance bearing option keep out contaminants and foreign matter, enabling the couplings to be used in less than ideal operating environments.

Schmidt Offset couplings are designed to handle high amounts of parallel offset up to 17 inches and are available with torque capacities up to 459,000 in-lbs. They impose no side loads on shafts or bearings and eliminate radial shaft vibrations.

Zero-Max
www.zero-max.com

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GERWAH couplings are utilized wherever servomotors are used and need a coupling device. Most applications include bottle capping, food processing, printing, machine tools, automation and packaging.

These new couplings are available in a wide range of sizes and torque capacities of up to 3,800 lb-ft. The couplings are field proven with its long durability, increasing machine operating times. The lightweight construction of this new GERWAH gives low masses to reduce energy costs and also increases machine performance.

“For over the past 30 years GERWAH engineers have specialized in coupling technology and have placed their German quality and engineering into every GERWAH product,” said Ringfeder Power Transmission USA Corporation President Carl Fenstermacher. “Not to mention that every component is made in-house for a super fit and finish.”

GERWAH couplings have already convinced all machine operators around the world about their unequalled quality. The PKN series from GERWAH couplings combines the proven and tested technical advantages of metal bellows couplings with a plug-in connection. Compared to other comparable solution, GERWAH couplings do not need any axial pre-load. These couplings make the mounting of shafts very easy, while remaining electrically isolating and completely backlash-free and even compensating misalignments. Hubs made of aluminum and metal bellows made of superior premium steel prolong the durability of these couplings.

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These couplings are offered from stock in a choice of six outside diameters from ½ in. (13 mm) to 2-¼ in. (57 mm) in both set screw style and clamp style. A large variety of inch and metric bore sizes starting at 1/8 in. (3 mm) is available with keyways offered on 3/8 in. (8 mm) and larger bores.

Ruland Manufacturing Co., Inc.
www.ruland.com

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These couplings, identified as the S50TLC… Inch and Metric Series are stocked in sizes 13, 19 and 25. These lightweight molded patented couplings can replace stainless/aluminum slit type couplings with lower cost and improved operation with no windup or backlash or any derating for reversing applications. It uses a metal screw-to-metal nut design to insure a tight fit between the shaft and the coupling, and does not use threads cut into the molded piece.

These couplings are made of engineered polymer and have stainless steel fasteners. Bore sizes range from 0.125 to 0.500 in. (3 to 12mm). They range in length from 0.710 to 1.400 in. (18 to 36mm) with a maximum temperature range of -4°F to +284°F (-20°C to +140°C).

The couplings can be used in a variety of applications and are especially able to accommodate tight or skewed connections. Quotes, online orders, available stock, and 3D CAD Model downloads are available at our new eStore at: www.sdp-si.com/eStore

Detailed specifications are contained in Catalog D795, available free upon request from Sterling Instrument, 2101 Jericho Turnpike, P.O. Box 5416, New Hyde Park, NY, USA 11042-5416.

Phone: 516-328-3300, Fax: 516-326-8827.

http://sdp-si.com/web/html/newprdcouplings10.htm

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The 2009 BK series catalog from R+W represents the latest collection of standard bellows coupling designs for applications requiring torque ratings from 15Nm – 10,000 Nm. Flanges, shafts, hollow bores and nearly any other mechanical interface are accommodated.

R+W America
www.rw-america.com

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Stafford Large Bore Shaft Collars and Rigid Couplings are custom engineered for applications up to 16” and 8” I.D., respectively, and come in one- and two-piece configurations that can be modified to meet a variety of special requirements. Ideal for wind power generator drive systems, they can be precision balanced and incorporate steel targets which can be read from both the face and O.D. to add speed sensing capability to shafts.

Stafford Large Bore Shaft Collars and Rigid Couplings can be machined from aluminum, steel, stainless steels, titanium, brass, and other alloys with dimensional tolerances of <0.001” and run-out and concentricity tolerances of <0.001” TIR, depending upon the part configuration. Modifications can include keyways, slots, cam surfaces, special threads and other features.

www.staffordmfg.com

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BRAINTREE, MA – Altra Industrial Motion has published a white paper entitled “Making the Grade in Metals” which outlines the firm’s technology solutions in worldwide metal producing, forming and fabricating operations.

“The multiple companies of Altra operate as the premier manufacturers of gear drives, clutches, brakes, couplings and other power transmission products that are at the heart of literally hundreds of applications in the metals industry,” says David Brooksbank, Altra Director of Marketing. “It’s not uncommon to find as many as 25 Altra gearboxes on a galvanizing line that might consist of a recoiler, an uncoiler, flattener, leveler, pinion stand, pinch rolls and bridle drives.”

Altra’s technology portfolio for the metals industry covers a wide range of operations from light-duty to heavy-duty applications where high-quality, rugged motion control products are needed to help ensure high productivity and reduce critical downtime.

To download a PDF file of “Making the Grade in Metals”, visit http://www.warnernet.com/litportal/markets.asp?mspid=12

www.altramotion.com

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“This new pump drive technology has become increasingly popular because of dramatic improvements in their energy efficiency and noise reduction”, reports Robert Mainz, Zero-Max sales manager. “These pump systems utilize the power and precision that only a servo motor can provide. The system pressure is controlled by modulating the output volume of a fixed displacement pump. This is made possible utilizing a high performance control system and the high performance qualities of a CD shaft coupling.”

CD couplings have unique design qualities that are robust to ensure that these hydraulic pump applications are reliable and productive. CD Couplings are designed so that the working part is made of a composite material. The composite disc design withstands the punishment and stress of a servo motor, “everything a variable speed pump drive system can dish out,” report OEM designers. They also report that CD couplings enable these systems to not only perform well in test lab environments, but more importantly, on the production floor.

www.zero-max.com

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Designs that provide a competitive edge combine simplicity of manufacture and assembly with durability and quailty in a compact design at a reasonable cost. Every component in an assembly should be evaluated and reevalulated routinely to determine if it could do more and do it better. Another name for its process is “value engineering.”

Each of the integrated, multi-featured products that Helical makes is a story unto itself. The diversity of the features displayed in these parts offers a glimpse into the productivity potential that can be had by using multi featured parts. The integrated, multi-featured part saves assembly time, conserves system space, and by virtue of its single piece name, assures backlash free performance. In almost every case, this means extended life and sizable cost savings to the customer. The only characteristic these parts have in common is the HELI-CAL® Flexure (flexible beam). All other features incorporated in each part were created specifically to customer requirements.

Visit www.Heli-Cal.com

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But in the case of hard stops, impacts and other situations where overload occurs rapidly, sufficient energy to do damage often exists in the rotating inertia driving the load. R+W servo-rated torque limiters are accurate to +/-5% release torque and positively disengage the motor or gearbox shaft in 1-3 milliseconds. Patented preloads and a specially designed spring system remove backlash and guarantee a low profile. Selection tool and personal sizing assistance are available at www.rw-america.com.

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The new quick clamping design shaft collars have advantages over their traditional one- or two piece clamp collars with screws and set-screw type collars: The quick clamping collars do not mar the shaft. They do not require tools to install or remove them, and are especially designed for quick adjustments. They also work well with light duty split hub components such as gears and sprockets and they can be machined to facilitate mounting of other components. The quick clamping collars are made from high quality aluminum with an anodized finish which has the advantage of being light-weight and having low inertia. The quick clamping shaft collars are available with bore sizes from 5/16″ to 1 1/2″ in the inch series and 8mm to 35mm in the metric series.

As all Ruland shaft collars, the new quick clamping design collars are single point faced to ensure perpendicularity and proper alignment. A precise shaft collar face to bore relationship ensures that components are both properly positioned and not tilted on the shaft. Collar face perpendicularity also ensures even pressure on interfaced components.

Ruland shaft collars are also available in one- and two-piece clamp-style designs and set-screw design. They are manufactured in a variety of materials including 316 stainless steel, 303 stainless steel, RoHS compliant yellow zinc plating, high-strength aluminum with an anodized finish, black oxide carbon steel, and engineered plastic.

Shaft collars are part of Ruland’s complete product line which also includes rigid couplings with precision honed bores and five types of zero-backlash motion control couplings: beam couplings, bellows couplings, oldham couplings, curved jaw couplings and miniature disc couplings.

www.ruland.com

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Two series of these zero backlash flexible beam couplings are offered for different types of applications. Available in aluminum for low inertia or stainless steel for higher torque and added corrosion-resistance, the couplings are available as standard parts in twenty different body sizes, with outside diameters ranging from 3/8 in. (10 mm) to 1 ½ in. (38 mm), and bores from 3/32 in. (2 mm) to ¾ in. (19 mm).

Ruland Manufacturing Co., Inc.
www.ruland.com,
http://www.ruland.com/ps_couplings_flexible.asp

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