Background

Without hinge: Difficult	With hinge: Easy

Hinges are often overlooked as a simple way to improve efficiency and physical demands on people. They should be considered whenever a single component of a piece of equipment must be temporarily removed, providing multiple benefits as shown below:

Additionally, hinges can be incorporated into tools to provide flexibility and changes in orientation.

Examples

Reduce time and exertion

No hinge: Much work	Hinge: Easy

Both photos above show heavy round access doors on similar equipment in electric power plants. At left, the doors do not have hinges, and when removed require a considerable amount of effort — they must be lifted, carried across a passageway to a vacant spot, and lowered to the floor. At right, with a hinge (arrow), the door is simply opened.

Both this example from a power plant and the one at the top of the page for a machine tool are relatively common, despite the fact that hinges have been used on doors for thousands of years. Part of the problem is habituation, the all-too-human failing where people become so used to seeing and doing something that they stop noticing.

(See also Maintenance: Access Panels and Machine Operation: Doors.)

Easy return to the same starting position

Hinge on conveyor gate

The conveyor gate above rides on casters and is hinged to the main conveyor. The gate could still be opened without the hinge, but then it would take more time and effort to maneuver it back into the correct position. The hinge enables an easy return to the the starting position.

[See also Material Handling: Conveyor Gates.]

Offset hinge

Note: Normally, an item on a hinge rotates in an arc that can conflict with adjacent items. When it is not possible to mount or recess the hinge on an interior surface (as with most household doors), then offsetting the hinge is an alternative. The offset creates a larger arc that can allow a better fit.

Easy removal from work space

Hinged monitor arm	Hinged toolrack arm

The hinges on computer monitor arms allow easy movement of the monitor out of the way. The same technique can be used for a host of other items in production workstations.

[See also Hand tool: Counterbalance arms and Workstation: Storage (articulating arms).]

Easy change in orientation

Hinge on tool handle	Hinge on slide

Hinges designed into tools and equipment can provide for easy change in orientation. The hinged electric screwdriver above left can be converted instantaneously from a pistol grip to an in-line grip. The U-channel slide

[See also Hand tool: grips and Material handling: Slides.]

Less risk of misplacing

Small items that are removed from equipment can be fitted with hinges in to keep them firmly attached and not susceptible to misplacement.