Ergonomics in the workplace

Increased safety and less fatigue for operators in the tightening sector

Machine manufacturers must refer to the European standards linked to the Machinery Directive 2006/42/EC for anything related to prevention of musculoskeletal disorders caused by frequent repetitive movements.

These characteristics are even more important considering the particular way in which screwdrivers are used, where the main causes of operator fatigue arise from:

• the pushing force needed during tightening

• reaction on the hand when the set torque is reached

• screwdriver weight

• screwdriver balancing

• vibrations caused by the tool

• inadequate and unsuitable way in which the work station is used.

Ergonomics has always been a strong point in the solutions developed by Fiam, which are designed and built to reduce any kind of operator fatigue, ensure the utmost safety during use and increase productivity performance.

These are the principles on which the new Cartesian arms have been designed and manufactured; in addition to cancelling vibrations and tool kickback on the operator's hand, they make it possible to hold the wrist in a good position and remain upright at the work station.

The benefits of Cartesian arms

Among the strong points of these new ergonomic aids for use with any tool, we find that:

- motion is extremely fluid and smooth

- a safety magnet holds the tool when the arm is in its rest position

- the horizontal end stops are damped with special devices

- the universal clamp makes it possible to install any tool up to 50 mm in diameter

- the horizontal arm can be quickly adjusted to different positions to cover a large work area.

Two models are available: BC Cartesian arms with simple linear travel, and BCA articulated Cartesian arms, which can open in a cantilevered manner from 0 to 120° to cover large work areas very ergonomically, while retaining a small footprint.

The position monitoring system: greater speed and production efficiency

All new Cartesian arms can be equipped with a position monitoring device to turn them into “Poka Yoke” tightening systems, which are very effective at making production cycles faster and more efficient.

Such a tightening system consists of:

• Cartesian arm complete with position monitoring device which processes either the angular movement of the Cartesian arm or its angular and linear movements

• TPM (Tightening Positioning Monitor) monitoring unit which stores the screwdriver positions and sequences and guides the operator through the tightening operations to ensure that the finished product is assembled in accordance with the defined specifications.

How does the guided positioning system operate?

• It works through “self-learning”: it locates the screwdriver position at the various tightening points and stores them together with the sequence of actions and the number of screws

• The TPM unit display offers a graphical system to guide operators progressively as they approach the tightening point

• The screwdriver is enabled when it is at the first stored position

• Each time a screw is tightened, the display shows how many screws are left, indicating that it is ready to pass on to the next screw

• A signal comes on when the stored cycle is complete, and gives the ok to proceed with a new work cycle

• During the storage process, it is possible to program a precision tolerance within its operating range.

Therefore, it is a tool conceived and designed to create works stations that offer improved ergonomics and performance, while ensuring greater safety and less fatigue for the operator.