...What if that's the assignment? What if your customer has put "ergonomic" on the wish list for the machine you're designing? What qualities should you be seeking in the components?
Diane posting today, and I found some specific answers to these questions in Occupational Health & Safety magazine. Here's what I learned:
- Look for handles that are smooth (as opposed to having grooves) so any size and shape of hand can use them. If the user's hand doesn't fit the grooves, it results in excessive pressure.
- Use knobs and handles covered in soft material—they are more comfortable, provide a firmer grip and reduce slippage.
- Design the machine so that operating components can be manipulated with the wrist in a straight position.
- For operations that require force, look for components whose grips have handle or knob diameters that range from 1 1/4" to 2." This allows for fingers to wrap comfortably in a firm hold.
- When precision is the requirement, choose components with grips in the 1/4" to 1/2" range. The smaller diameter prevents overexertion of fingers, knuckle joints, and hand muscles.
- Keep in mind the position of the operator and space constraints when positioning operating elements. Avoid awkward work postures and wrist positions.
- Whenever possible, design the operating components to be used without pressure on the palms of the hands, which are full of pressure-sensitive nerves and blood vessels.
The components we sell at J.W. Winco are high quality, smartly-designed parts. Many of our components and tools are specifically designed for ergonomic requirements, like the EN 5337.6 Softline star knob, the 6830-NI stainless steel horizontal action toggle clamp, and the No. 906GE ball-ended hex key, all pictured on this post. Just visit our Web site and use the search feature to look for "ergonomic" and you'll find plenty of fine examples.