Lead Screw Actuators

Rollnuts

Standard Rollnuts are the workhorse of the family. They are used in machine tools, small elevators, and sliding doors. Almost anywhere rotary motion must be converted to linear motion.

roll
Design Specifications:
Shaft Diameters: 1/2 to 6 inches
Shaft Material: Hardened alloy or stainless steel standard, others available.
Nut Material: Selected to be compatible with application.
Leads: Up to five times the shaft diameter. Custom thread forms available.
Backlash: .003" depending on application.

Miniature Rollnuts

MNAI's line of miniature Rollnuts are designed for use in mechanisms where precise, repeatable positioning of small samples, products, sensors or probes is essential. MNAI Miniature Rollnuts have been used extensively in laboratory instruments, including medical diagnostic and clinical instruments, which require precise and repeatable insertion and withdrawal of sensors, cuvettes, probes or samples, in any plane.

mini

The roller assembly consists of a hardened, ground tapered roller rotating in sealed, lifetime-lubricated ball bearings. Coupled with the use of dry lubricant surfaces in the thread grooves, this lifetime-lubrication results in virtually maintenance-free operation. Consequently, Miniature Rollnuts can operate in hostile environments that include dust, dirt, moisture, radiation, high vacuums and others. Operating temperature range is from -100° to +350°. Because the nut assembly has centralizing bearings at both ends, it can tolerate side loads. This feature also assures accurate alignment.

Design Specifications:
Shaft Diameters: 1/8 to 3/8 inches
Shaft Material: Hardened stainless steel.
Nut Material: Selected to be compatible with application.
Leads: Up to four times the shaft diameter. Custom thread forms available.
Backlash: Less than .005"

Guided Miniature Rollnuts and Rollnut Actuators

MNAI motion control products can also include guided versions of the Rollnut and Miniature Rollnut with a self-contained guide system, custom designed to fit your precise specifications.

1 Miniature Rollnut Assembly for Custom X-Y Table   Miniature Rollnut Assembly for Medical Z-Drive 3
2 Guided Rollnut High-Temperature Medical Assembly   Guided Minature Rollnut Medical Assembly 4

Rollnut Longspans

Longspans are designed for use where the nut must travel long distances-up to hundreds of feet. The screw shaft is modular to permit easy on site assembly and minimize vibration. The shaft is supported by hangers at intervals to prevent sagging, whipping and misalignment. Unique slotted nut design permits it to pass over the supports. Lead flexibility reduces screw RPM, yet maintains high linear rates, offering high speed operation with low noise levels.

long
Design Specifications:
Shaft Diameters: 1 to 6 inches
Shaft Material: Hardened alloy or stainless steel standard, others available.
Nut Material: Selected to be compatible with application.
Leads: Up to five times the shaft diameter. Custom thread forms available.
Backlash: From .005" - .03", depending on size.