Patent ID: 8776917

Claim:
A stair-climbing apparatus, comprising: a platform having a first end, a medial portion, and a second end portion opposite the first end, the platform defining a width; a plurality of wheel trucks adjustably disposed beneath the platform, each of the wheel trucks having a first end, a second end disposed laterally opposite the first end, and a span extending between the first and second ends, the span being substantially equal to the width of the platform; a first wheel extending from the first end of each of the wheel trucks; a second wheel extending from the second end of each of the wheel trucks; a first end wheel carriage immovably affixed beneath the first end of the platform; a medial wheel carriage disposed beneath the medial portion of the platform, the medial wheel carriage being horizontally positionable along the medial portion of the platform; and a second end portion wheel carriage disposed beneath the second end portion of the platform, the second end portion wheel carriage being horizontally positionable along the second end portion of the platform.