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Zero-Max – Shaft Couplings, Keyless Bushings, Adjustable Speed Drives

Zero-Max Brand LogoISC Companies and Adams-ISC can supply the Zero-Max products on this page and many others found on the Zero-Max website. For more information or for a product quote, please contact us by phone 763-559-0033, by email custserv@isccompanies.com, or by filling out our online contact form.

Zero-Max is a leading provider of motion control solutions and one of the industry’s most trusted coupling manufacturers. Products include composite disc couplings, servo couplings, offset couplings, torque limiters, right angle gear drives, linear actuators, and mechanical variable speed drives. Zero-Max products are known throughout the world for their innovative designs, high quality, high performance, and durability.

Zero-Max Trademarks/Names: ServoClass, Roh’lix, Control-Flex, OHLA, Posi-Lok, Crown, Phas-Lok, ETP (ETP-CLASSIC, ETP-EXPRESS, ETP-TECHNO, ETP-POWER, ETP-HYLOC, ETP-HYDROPRESS)

Product Groups


Flexible Shaft Couplings

Composite Couplings

Composite Disc shaft couplings deliver high performance with zero backlash and are designed to withstand the punishment and stress of demanding servomotor applications. These high speed flexible shaft couplings are ideal for cyclic applications where speed and repeatable accuracy are critical. Other brands may have high torsional stiffness; but are too brittle to withstand the punishment of high speed, reversing applications.

The working parts of these disc couplings are made of high precision composite material. This unique design has high torsional stiffness, yet allows for misalignment in high stress applications. They have excellent chemical and moisture resistance and can operate without maintenance in hostile environments.

Single-Flex Configuration Composite Couplings

Double-Flex Configuration Composite Couplings

Floating Shaft Configuration Composite Couplings

Floating shaft couplings, or spacer couplings, are three-part assemblies consisting of a floating tubular shaft with an integrated flexible coupling attached to both ends. Floating shaft couplings are designed to transmit torque and accommodate misalignment in applications where drive and load components are spaced far apart.

ServoClass Flexible Couplings

ServoClass couplings provide the optimal blend of performance, durability, and price. They are manufactured from high quality materials using state-of-the-art CNC manufacturing equipment. ServoClass shaft couplings are ideal for servomotor actuators.

Control-Flex Flexible Shaft Couplings

Control Flex shaft couplings are specially designed  for use with feedback devices such as encoders. They are engineered for zero backlash operation to ensure encoder accuracy. Additional features include clamp hubs for vibration-resistant shaft engagement and flex elements which provide low bearing reaction loads.

Schmidt Flexible Couplings

Schmidt shaft couplings are uniquely designed to handle applications with challenging or extreme misalignments, including models for offset and inline shaft applications.

Wind Turbine Products

Zero-Max has developed an advanced, all-in-one disc coupling solution for wind turbine drivetrains with capacities up to 5MW.

Zero-Max’s torque limiters protect wind turbines against peak loads, reverse torques, and grid shorts. Shaft-mounted to the generator shaft, our wind turbine torque limiters are factory-set to slip at specific torque settings, ranging from 4,000 to 50,000Nm.

Overhung Load Adapters

Overhung load adapters are hydraulic system components that protect shaft seals and prevent breakdown by absorbing internal and external stress from the motor and pump. They also provide a seal to protect motor components and prevent contamination of hydraulic fluid. SAE overhung load adapters prevent costly damage to shaft seals and are used for fan drives, recycling equipment, mixer units, industrial conveyor drives, and various other hydraulic motor applications.

Roh’Lix Linear Actuators

Roh’Lix linear actuators are threadless, mechanical, screw-type devices designed to convert rotary motion into precise linear motion and thrust using rolling element ball bearings. These adjustable automatic overload protectors will slip when overloaded, providing linear clutching without any additional clutch mechanisms.

The Roh’Lix is intended for horizontal or vertical axial loading applications. Sideloads and twisting loads should be avoided whenever possible, as they cause uneven bearing loading and can shorten lifetime.

Phase Adjusting Hubs

The Phas-Lok Adjusting Hub is an economical, yet precision device that provides an easy way to change the phase relationship of a drive component and shaft. It is ideal for fine-tuning timing adjustments, adjusting for chain elongation, and sprocket tooth wear.

Adjustable Speed Drives

Adjustable speed drive speed adjustments are easily made by moving a lever control through an arc or turning the hand-wheel of a screw type control. In either case, easy and precise speed control settings are possible with Zero-Max adjustable speed drives – also referred to as variable speed drives.


Crown Gear Right Angle Gearbox

Crown Gear is a brand of right-angle gear drive boxes designed for dependable, economical transfer of speed or power. These high-performance gears are mounted to input and output shafts positioned at 90-degree angles, allowing the gearbox to intersect with a plane or cross on two parallel planes. Both series are available in 1:1 and 2:1 speed ratio with two-way (one output shaft) or three-way (two output shafts) versions.

Crown Gear gearboxes are available in two versions;

  • Standard, black anodized aluminum housing, stainless steel shafts
  • IP65-Rated, nickel-plated aluminum housing, stainless steel shafts, shaft seals, food-grade grease

Overload Safety Devices

Torq-Tender overload safety devices incorporate torque limiters for dependable overload protection. When a jam-up or excessive loading occurs, the built-in torque limiter will reliably and quickly release to prevent system damage. Torque value is controlled by the part number that is ordered; that value determines what spring is used during assembly of the torque limiter.

Keyless Shaft Bushings

Keyless shaft bushings provide solid connections between the shaft and hub, without stress or wear to mounted components. Using hydraulic pressure to maintain their position, they eliminate keyways, tapers, and tapped holes, which can cause component stress and wear due to fretting, corrosion, and backlash.

Keyless shaft bushings enable fast, precision mounting of shaft components, providing solutions in the following situations:

  • Where frequent readjustment is required, either rotationally or axially, such as during machine changeover
  • In systems where balance and runout are inherent problems
  • When repeated fastening, adjusting, and holding of shaft components is required
  • Where downtime is critical and costly
  • Where precise mounting location is critical

ETP Keyless Bushings

ETP keyless locking devices are designed to solve specific application requirements, such as phasing and timing to synchronize machine components. They feature double-walled sleeves and tightening mechanisms that form solid, continuous connections between shafts and hubs when tightened.

Posi-Lok Keyless Bushings

Posi-Lok (PSL) keyless shaft bushings are locking devices that provide a secure shaft-to-hub connection. Most models feature socket-head cap screws for easy tightening and distribution of pressure over the full length of the connection to reduce fretting, corrosion, and backlash. They are ideal for positioning and locking shaft components, and eliminate the need for keyways, tapers, and tapped holes, which can weaken or cause excess wear to shaft couplings.

Posi-Lok keyless shaft bushings utilize tapers that form a mechanical locking wedge as the actuation screws are tightened, pressing the inner sleeve against the shaft and outer sleeve against the hub. The resulting connection transmits high levels of torque and resists axial forces.

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ISC Companies and affiliate Adams-ISC are industrial distributors of bearings and mechanical power transmission parts. We have many different models and brands in stock for fast delivery. Our sales professionals are happy to assist you in the selection process to ensure the correct part is specified for your application. Get a quote by clicking below on “Request Pricing” and filling out the contact form or give us a call at 1-800-627-9434.

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