What are Flexible Couplings?

Couplings join together two shafts as a way of transmitting power from one to the other. It is part of the drivetrain which may include other power transmission components such as lead screws or ball screws, gearboxes, belts and pulleys or chains.

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.

RR Fisher & Co releases R+W Safety Couplings for particle measuring systems

RR Fisher & Co. Ltd. (www.rrfisher.com.au) has announced the release of its ATEX certified R+W safety couplings for Sympatec’s (www.sympatec.com) particle measuring systems. These safety couplings offer an ATEX design with high-temperature steel plug segment.

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.

Zero-Max Zero Maintenance Bearings

Plymouth, MN – Zero maintenance bearings are now available as an option for Schmidt Offset couplings from Zero-Max. This new coupling feature eliminates the need for periodic coupling lubrication and the resulting system downtime.

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

Slit Type Plastic Couplings from Sterling Instrument

New Hyde Park, NY – A new series of slit type plastic couplings from Sterling Instrument features low cost, UV resistance, voltage and RF isolation.

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

2009 BK Series Catalog from R+W

For highly dynamic and accurate servo driven systems, stainless steel bellows couplings have been a mainstay for some years. Their increasing prevalence has driven the development of a very wide variety of mounting configurations, wall thicknesses, lengths, torque ratings, etc.

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

Stafford Large Bore Shaft Collars and Rigid Couplings

Large bore shaft collars and couplings that can be custom engineered for drive train applications in wind power generation systems are available from Stafford Manufacturing Corp. of Wilmington, Massachusetts.

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

Helical Products

The demands put upon today’s design engineers seem to increase yearly. It is little wonder engineers are reaching for the Rolaids with one hand and the assistance of industry specialists with the other. Clearly the pressure is on engineers to produce designs that create competitive edge.

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

R + W Couplings

Protection of an electromechanical system from torque overload is often assumed to be guaranteed by the current limits set in the drive parameters.

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.