Wheel pair for a stable mechanism to propel a mating concave spherical surface along two axes of rotation

A novel design of a spherical joint for use in motion control systems, being movable in rotation about “Axis A” and “Axis B” as defined in FIG. 1, whereby each joint (1) is composed of a pair of coaxially mounted wheels (2) and a mating concave spherical surface (3)

• Each wheel includes a center part (4) rotatably mounted on a center axle (5), and further includes a plurality of parts for engaging the mating concave spherical surface (3) rotatably mounted on the center part (4) and distributed around the same, characterized that each mating concave spherical surface engaging part is designed as an elongated roll (6) having the outer side thereof convexly vaulted in the longitudinal direction thereof, and that each roll (6) is disposed in the center part (4) having the longitudinal center axis (6.1) thereof obliquely positioned in relation to the center axis (4.1) of the center part (4), and furthermore that the distance at which the rolls are positioned in relation to the center axis (4.1) around the center part (4) is selected in such a manner, as well as the specific convex revolved profile of the roll (6) being selected so that the rolls make suitable and unbroken contact with the mating spherical surface (3).