Constant Force Springs for OEM Manufacturers

Hunter Spring supplies custom power and data cord reel solutions to the industrial OEM industry.

Image Credit: Shutterstock | ssguy

The company’s rugged cord reels are designed to withstand the most challenging environments and can be found in a number of manufacturing works centers and garage bays. The cord reels can be incorporated into mobile equipment such as:

  • Mobile laboratory equipment
  • Pallet trucks
  • Electric forklifts
  • Work stations

In addition, Hunter Spring supplies springs and spring powered cable reels, also known as cable winders, for general industrial applications used in rewinding, counterbalancing, and retrieving applications.

The company’s spring reels, power springs, and constant force springs can be used in many applications such as closing doors, counterbalancing, constant tension machine covers, and much more. Customers are invited to consult with Hunter Spring, who can formulate efficient and versatile custom spring and reel solutions.

a man in a blue coat looking at a yellow machine

Constant Force Springs (NEG'ATOR)

The NEG'ATOR constant force spring, supplied by Hunter Spring, is the most basic, yet most versatile, type of constant force extension spring. The NEG'ATOR is a prestressed flat strip of spring material that is formed into almost constant radius coils on a drum or around itself.

When the spring material is deflected, it straightens as it exits the drum. The spring’s straightened length stores the spring’s energy through its tendency to assume its natural radius.

a spring

Hunter Spring supplies constant force springs for high-quality extension springs. The constant force springs are made from 301 High Yield Stainless Steel. For custom applications, other materials such as Inconel, Elgiloy, or high-carbon steel can be used upon request.

The constant force springs offer low force gradient over the entire deflection range and allow extremely long linear extensions.

Due to the light weight and inherent compact size, smaller package sizes are possible when using constant force springs. Negative force gradients can be achieved by using special manufacturing techniques.

For applications where space is limited, springs can be easily wound together in a laminated assembly to multiply the output force, without causing any major effect on spring size and fatigue life.

Both standard and custom constant force spring designs are supplied by Hunter Spring.

Customers can use the constant force spring design worksheet to specify their requirements. This will allow the company’s Application Engineers to provide a design that meets their requirements.

Download the Brochure for More Information

Constant Torque Springs (NEG'ATOR)

The NEG'ATOR constant torque spring motor is a prestressed strip of spring material that is formed into a coil and stored on a compact storage drum. Following this, the free end is fixed and backwound onto a larger output drum; this is the "winding" part of the constant torque spring's cycle.

a coiled spring

When torque on the output drum is reduced, the spring will return to the storage drum to assume its natural curvature, rotating the output drum and offering virtually constant torque.

Constant torque springs from Hunter Spring offer minimal intercoil friction and resultant hysteresis. The springs provide rotary motion directly from the output drum or linear displacement through the use of spool or cable attached to the output drum.

The springs are made of type 301 high-yield stainless steel, and are delivered in coils for mounting on motor drums.

Hunter Spring supplies an array of standard constant torque springs. Constant torque springs are also offered as custom spring solutions to suit customers’ specific requirements. Customers can use the constant torque spring design worksheet to specify their requirements.

Download the Brochure for More Information

Custom OEM Mechanical Reels

Mechanical spring reels provide an alternate counterbalance or retrieving solution in situations where the use of a simple spring is not practical, feasible, or desirable due to space, motional, or aesthetic constraints. The retracting force is obtained through the attachment of a cable which remains constantly tensioned by the spring in the mechanical reel assembly.

As a flat spring manufacturer, Hunter Spring has the knowledge and equipment to design and test specialized and highly precise springs. In cases where commercial off-the-shelf (COTS) mechanical cable reels do not fully meet a customer’s requirements, the company works closely with OEMs in the medical, aerospace, trucking, and transportation industries to develop custom spring reels for specific applications.

Customers can use the custom mechanical cable reel design worksheet to specify their requirements. This will allow the company’s Application Engineers to provide a design that meets their requirements.

a person on a laptop

For over 100 years, the company has been using the science in springs to resolve challenges for OEMs.

This information has been sourced, reviewed and adapted from materials provided by Hunter Spring.

For more information on this source, please visit Hunter Spring.


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