Precision Lead Screws (commonly called Power Screws or Translation Screws) are designed for high-precision actuation. Lead Screws use helical threads to translate rotary motion into linear movement. These mechanisms are used within a wide range of appliances, including printers, lathes, CNC machines and robotics.
Accu supply a selection of matched Lead Screw Nuts in a range of materials from A2/A4 stainless to carbon steel. The range includes flanged and unflanged varieties, and they are available with and without anti-backlash capabilities.
Lead Screw Basics
Lead Screws rotate using teeth (or single tooth) to push a Lead Screw Nut back and forth in very precise increments. The ‘lead’ of a Lead Screw is the distance moved during one 360° rotation of the screw. Smaller leads results in a tighter thread, which allows for more precise movements per rotation. The ‘starts’ of a Lead Screw are the number of teeth on the Screw itself. A larger number of starts results in a more robust mechanism with a greater ability to transmit torque, but multiple ‘starts’ can sometimes be incompatible with a small ‘lead’ due to space limitations.
Lead Screws are becoming increasingly useful in industrial engineering applications requiring very intricate movements and ultra-high precision actuation. These include high precision robotics, animatronic limbs, and in hospital medical equipment such as centrifuges and automated pipetting systems.
Lead Screws are sometimes confused with threaded rods/bars but it is important to understand that due to the much finer threads on a threaded rod - there is an increased risk of thread deformation under load.
Lead Screw Types
Imperial ACME Lead Screws and Nuts
ACME Imperial Lead Screws are one of the most commonly used forms of Lead Screw. These screws feature a trapezoid-shaped tooth, with a tooth angle of 29°. ACME Lead Screws have a more acute tooth angle than Trapezoidal Lead Screws, which results in greater efficiency, but slightly decreased load-bearing capabilities.
Metric Trapezoidal Lead Screws and Nuts
Accu's Trapezoidal Metric Lead Screws feature a trapezoidal tooth profile, and a tooth angle of 30°. Trapezoidal Lead Screws have a similar tooth shape, but a shallower tooth angle than ACME Lead Screws, which creates stronger teeth with greater load-bearing capabilities.
What Are The Advantages Of Using Lead Screws?
Accu Lead Screws have a number of key advantages over alternative power transmission methods:
Ultra-High Precision Lead Screws
Accu's High Precision Lead Screws can be precisely operated to achieve lead accuracies of up to 0.0001mm/mm. This highly accurate linear motion makes Lead Screws ideal for applications where precision is critical.
Large Load-Carrying Capacity
Lead Screws are capable of supporting very large axial loads. This capability is further enhanced by using Lead Screws which feature multiple thread starts.
Large Mechanical Advantage
Due to their unique design, Lead Screws are able to exert high levels of torque with relatively little breakaway torque.
Compact and Simple Design
Lead Screw mechanisms have only a small number of essential components, and take up very little space within an assembly, this makes them simple to design and install, and means that they can be utilised in environments where space is limited.
Bespoke Precision Lead Screws & Nuts Manufacture
High precision, bespoke manufacture of Precision Lead Screws & Nuts to customer specification. State of the art facilities specialising in both small batch prototyping and large scale manufacture.