Patient beds used in health care facilities and home care settings often include a lift system allowing a patient or caregiver to adjust the height of the bed. The lift system must satisfy a number of potentially conflicting constraints. For example, the lift system should be quiet, dependable, safe and damage resistant. It should also be inexpensive to manufacture and should be adaptable to different bed models with no more than simple, inexpensive modifications. Because the lift system typically resides underneath the elevateable components of the bed, it must be compact enough to allow the bed to be positioned at very low elevations and yet must also have enough reach to position the bed at elevations high enough to be satisfactory for the caregiver. Compactness also makes space available for other under-bed components.