Component integration and the potential reduction of overall part count can reduce assembly time, conserve assembly space, reduce inventory space and related purchasing costs. Other features or functions that can be incorporated into machined springs include consistant spring rates, precise preloads, and multiple integral coils (multi-starts), aspects not possible with traditional type springs.
Machined springs can be configured to provide very precise, linear deflection rates because virtually all residual stresses are eliminated. As a result, there are no internal stresses to overcome before deflection occurs.
Machined springs can be used as compression, extension, torsion, lateral translation and lateral bending springs and can be made from any machinable material such as aluminum, stainless steel, and titanium

HELI-CAL Flexured U-joints Provide Precise Operating Characteristics

A universal joint is a mechanical connection between rotating shafts which are generally not in parallel, but intersecting. "U-joints" transmit torque.

U-joints are used in a variety of applications, wherever handling significant angular misalignment is the main focus. Typical applications include: articulating mechanisms, food processing equipment, replacement for expensive gearboxes, and drives where motor position must be moved angularly off centerline of the driven unit.

The oldest and most common type of u-joint is called the Cardan or Hooke type joint. It consists of two yokes, one on each shaft, connected by a cross shaped intermediate member. These popular u-joints are frequently used in automotive applications. Because the design incorporates several different piece parts, the moving parts of this type of u-joint usually require lubrication; and as the joint wears, the amount of backlash or free play within the joint itself grows. Even a lubricated Cardan u-joint will require periodic maintenance, and may leak lubricant.

Performance wise, Cardan u-joints can transmit relatively high torque with minimal radial loads. But, by design these u-joints are incapable of compensating for parallel offset and axial misalignment. Cardan types also introduce rotational inconsistencies into drive systems, a phenomenon known as "non-constant velocity rotation."

The "HELI-CAL Flexure" is an advanced and unique u-joint solution that generally exceeds the capabilities of common u-joint designs. A Helical u-joint is really a flexure capable of over 5° of angular misalignment. It may accommodate up to 90° of angular misalignment in certain circumstances. This type of u-joint will also compensate for axial and parallel misalignment.

A frequent application of the Helical flexured u-joint is the direct replacement for a 90° bevel gearbox. Gearboxes are expensive, and usually need lubrication for their meshing gear surfaces and bearings. Replacement with a maintenance free Helical flexured u-joint can save money, both on initial purchase price and on maintenance costs. Flexured u-joints can be beneficial most anywhere—for example, aerospace, appliances, electronics, control mechanisms and drives, medical and optical devices, sewing machines, instrumentation, and textile machinery.

The performance capability of each HELI-CAL Flexure is determined by six major characteristics: flexure outside diameter, inside diameter, coil thickness, material, number of coils, and number of starts. By altering these characteristics, torque capacity, angular and parallel misalignment capabilities, torsional and lateral bending rates of flexured u-joints can be modified to suit specific specifications and/or requirements.

By using a flexured u-joint, the designer/customer benefits from:

· Choice of materials

· Infinite choice of end attachments

· Optimized misalignment and torque capacities

· A variety of torsional and lateral bending rates

· Ability to run in either manual or motor-driven applications

· Constant velocity

An added bonus--flexured u-joints do not have:

· Backlash

· Moving parts

· Maintenance and lubrication requirements

· Limited selection of capabilities and sizes

· Limited angular misalignment capability

Once the designer/customer provides Helical with the performance requirements for his device, machine, or equipment, a specific flexure design that will meet or exceed his expectations is developed. An attachment may also be specified to securely interface with adjacent componentry. The result is a HELI-CAL flexured u-joint that works as an integral part of the customer's application.

HELI-CAL flexured u-joints are tailor made for customer applications, using customers' specific requirements as a starting point. The finished product is a HELI-CAL flexured u-joint that "fits like a glove" in the device, machine, or equipment.

Helical Products Company, with its unique HELI-CAL Flexure, covers most u-joint requirements. Whether the application requires just a small angle of slightly more than 5° or one calling for a 90° bend, Helical has a "flexure" answer. This "answer" employs the infinitely variable HELI-CAL Flexure, with its amazing range of variable characteristics. No longer is it necessary to use a "one size fits all" approach to u-joints.

Features

• No maintenance, lubrication or backlash.
• Available in aluminum and stainless steel with 2, 2.5 and 3 inch OD. Standard with quick change tapered bushings.
• Offered in inch or millimeter bore sizes up to 1 3/4 inch diameter.
• Torque capacities up to 1800 lbin.
• High torsional stiffness rates.
• Compensates for angular, parallel and axial misalignment.
• More torque for less money.

Designer's Comments

The PowerFlex is essentially a very cost effective power transmission coupling. The benefits include no lubrication, no maintenance, no keyway requirements and zero backlash. Plus, the product provides more torque for less money than past Helical power transmission coupling offerings of the same size range.

Four key elements have been incorporated to create the PowerFlex: the HELI-CAL Flexure, the convenience of removable tapered bushings, high torque capacity (up to 1800 lbin), and substantial misalignment capability.

Early on in the PowerFlex design process, it was recognized that the time tested and proven HELI-CAL Flexure should be utilized as the key coupling component.

After reviewing various combinations of coil thickness, number of coils, number of "starts" and flexure ID's, we arrived at a double start HELI-CAL Flexure configuration that accommodates sizable misalignments, and provides substantial torque capability, high torsional stiffness, and reasonable pricing. This represents value for the customer, which is always a key goal when we develop a new series of couplings.

This innovative design provides a flexible shaft coupling that can compensate for many operational variables, such as parallel offset and angular misalignment present anytime two shafts are being attached. The PowerFlex's unique flexing element also accommodates axial motion between two shafts. The PowerFlex is available in anodized aluminum and stainless steel. Shaft sizes range from .50 to 1.75 inch diameter. Torque capacities range from 250 lbin for the 2.0 inch OD aluminum to 1800 lbin for the 3.0 inch OD stainless steel coupling.

The new couplings are configured with two flexing elements, each consisting of two curved beams spaced 180 degrees apart. Each curved beam is a spiral configuration that provides a beam long enough for good flexibility, but short enough to be torsionally stiff. This high torsional stiffness is exceedingly important in motion control systems where position accuracy is critical. Each double beam element can bend 2 degrees for a total of 4 degrees angular misalignment. The flexing elements are used in pairs to allow for parallel offset between two shafts.

The double beam configuration of the PowerFlex provides a stability that makes it well suited for high rotational speed applications up to 6,000 RPM. Since all the flexing for misalignment is taken up by the beams, (made from a single piece of material), the PowerFlex is perfect for those troublesome power transmission applications. The single piece flexing element makes this coupling essentially maintenance free. Besides featuring high torsional stiffness, the PowerFlex is also backlash free, making it particularly well suited to high torque motion control applications. The PowerFlex offers considerable savings in maintenance costs (there are none) in applications where lubrication access is restricted or near impossible.

A tapered bushing attachment provides a positive method to hold the coupling to the shaft. The bushing's taper angle is low enough to give good concentricity and torque transmission capacity yet high enough to release the bushings from the coupling easily. Installation is achieved by sliding the bushing up the shaft, and placing the coupling into position. The bushing is tightened by progressively torquing the hex head screws to the specified torque in a star pattern. This star pattern tightening sequence is then repeated on the other end to complete the installation. Since the holding capacity of the tapered bushing is more than the maximum torque capacity of the coupling, keyways are not necessary.

Removal of the PowerFlex is accomplished by removing the hex head screws from both ends. The tapered bushings are released from the coupling by threading two of the hex head screws into the threaded holes of the tapered bushing flange. By tightening the hex head screws the tapered bushing is pulled from the coupling and the friction taper attachment is released.

Because we machine precision bore sizes into the tapered bushings, PowerFlex couplings can be assembled quickly to suit customer needs and delivered fast. Customers also may make coupling bore size changes themselves.

The PF Series PowerFlex is available in both inch and millimeter bore sizes in aluminum or stainless steel. Many sizes are available for immediate delivery.

AGC motorized mechanical goniometers are used in applications where 90° of angular travel is needed with the payload at the center of rotation, or where two axes of rotation are needed about a common point. AGC goniometers can be mounted to standard optical tables, as well as standard Aerotech rotary stages, to provide roll, pitch, and yaw about a common 3-axis intersection. Performance includes ±12 arc sec accuracy, ±10 arc sec repeatability, 3.5 arc sec resolution, a maximum speed of 78 degrees/second, and a maximum load of 50 kg. This flexible stage series is ideal for optical alignment, payload tip/tilt, beam steering, sensor calibration, laser applications, automated manufacturing and/or testing, and multi-axis diffractometer systems.

Construction Features
Multiple AGC goniometers can be mounted on one another to form a rotary system with all axes of rotation sharing a common intersection point. This allows compact pitch/roll/yaw systems to be created easily from a standard stage platform and without special adapter plates or mating fixtures. The drive mechanism for AGC stages is a precision gear and matched worm that are preloaded to reduce backlash. All AGC stages include optical limit switches and hard stops to define a ±45° range of travel. Innovative direct feedback technology yields stable performance and negligible performance drift over the life of the stage. This is in stark contrast to other designs that must be continually adjusted to compensate for worm wear. All stage tabletops feature hard coated aluminum, with stainless steel Heli-Coil^® inserts to prevent thread wear.

Flexible Options
Options include flexible motor selections as well as a direct encoder mounted along the stage travel to offer outstanding repeatability and to minimize hysteresis and backlash. Vacuum-compatible versions, for use in pressures as low as 10^-6 torr, are also available.

A Complete Motion Solution
Standard AGC stage configurations feature Aerotech's brushless servomotors, while stepper and brushed motors are available. Aerotech offers a complete motion solution by offering advanced single and multi-axis motion controllers, linear and PWM drives, calibration and performance documentation, and all accessories necessary for your system.

The magnetic shielding Lab Kit is highly effective in solving design problems of magnetic interference. (D.C. to 100 kilohertz). By adding CO-NETIC and NETIC layers until desired attenuation is achieved, minimum material requirements can be determined. This results in significant cost savings in the final design.

An important advantage of the "hands-on" shielding approach is that changes in a circuit layout, shield configuration, power levels and component orientation are easily evaluated. Each consideration is evaluated without reliance on theoretical formulas that are imprecise. The Lab Kit permits magnetic shields to be designed and modified until required performance is obtained. The prototype then serves as a model for production.

Lab Kit Contents

The Lab Kit provides a wide variety of CO-NETIC and NETIC alloys. The material included is Perfection Annealed and will not require re-annealing unless severe forming or heli-arc welding is performed.

1 - CO-NETIC AA Foil .002" x 4" x 15" / 0,051 x 101,6 x 381,0 mm
1 - CO-NETIC AA Foil .004" x 15" x 10" / 0,102 x 381,0 x 254,0 mm
1 - CO-NETIC AA Foil .010" x 15" x 10" / 0,254 x 381,0 x 254,0 mm
1 - CO-NETIC AA Alloy .025" x 15" x 10" / 0,635 x 381,0 x 254,0 mm
1 - CO-NETIC Braided Sleeving 1/2" I.D. x 1 FT. / 12,7 mm x 30,48 cm
2 - NETIC S3-6 Foil .004" x 15" x 10" / 0,102 x 381,0 x 254,0 mm
1 - NETIC S3-6 Alloy .030" x 15" x 10" / 0,762 x 381,0 x 254,0 mm
1 - roll Double-faced Pressure Sensitive Tape
1 - A.C. Magnetic Probe, Model EP-101A
1 - Product Information Binder

Magnetic Pickup Probe

The A.C. Magnetic Field Evaluator Probe furnished with the Lab Kit can be used with a DVM or oscilloscope. It will measure magnetic field intensities and the attenuation ratios of magnetic shields. The nominal probe output is 20 millivolts peak per Gauss at 60 Hertz. The probe is accurate for direct measurements from 10 Hertz to 3 kiloHertz. Above 3 kHz it should be used only for measuring relative intensities. Each probe is carefully calibrated with the calibration number shown on the probe label.

Magnetic Shield Design

THEORY:

For D.C. and low frequency A.C. magnetic fields, a magnetic shield provides a low reluctance magnetic path for the interference field. The shield attracts flux lines to itself and diverts the magnetic field away from the sensitive component. This principle is basic in determining the design of a magnetic shield.

SHAPE OF SHIELD:

The optimum shield is a closed, spherical configuration. In practice, effective shields can be cans, open-ended cylinders, five-sided boxes, U or L shaped brackets, and even flat plates. A flat plate is effective if both the length and width of the shield exceed the distance separating the source and receiver of interference.

Please click on the links to the right for more information.

Cyclops 4" x 24" Type COR Safety Sight Glasses are often used as a liquid level gauge in various applications. The Cyclops patented lens retension system fuses the lens assembly to the lip of the ferrule with a teflon gasket and it is bonded into the inside of the ferrule with a strong, resilient, heat and chemical-resistant compound, forming it into a single unstressed unit.

Supplied with a Cover Flange, Cushion Gasket, Socket Head or Hex Head Bolting and Stainless Steel Heli-Coil Inserts, Cyclops 4" x 24" Type COR Obround Safety Sight Glasses offer superior safety and vastly reduced maintenance costs.

Sight Glass components are available in PVQ Quality Steel Plate or Stainless Steel in conjunction with either Tempered Soda Lime Glass or Tempered Borosilicate Glass Discs, rated for 200 PSI service to 450 F operating temperature.

"Cyclops Safety Sight Glasses - Safety Eyes for Industry"