Abstract: A friction drive stairlift has a pair of drive wheels in frictional engagement with an upper surface of a stairlift rail. The drive wheels are mounted to rotate in a vertical plane passing through the centreline of the stairlift rail. The rail is preferably formed from two substantially parallel tubes and the carriage is maintained perpendicular to that part of the rail with which it is in contact at any particular time.

Abstract: A compact screw drive stairlift has the drive screw retained in a cavity within the rail and engages drive transfer elements extending along an inner surface of the cavity. The combined configurations of the screw and the rail ensure that the stairlift carriage is retained on the rail.

Abstract: A friction drive stairlift has a single drive wheel mounted to rotate in a plane passing through the centreline of the stairlift rail. The rail is preferably formed from two parallel tubes and a facility to maintain the chair level as the stairlift passes through a transition bend is preferably mounted on the same axis as the friction drive wheel.

Abstract: The invention provides a levelling system for the chair of a stairlift, a characteristic feature of the system being the provision of a safety back-up or locking mechanism that will lock the position of the chair in the event of failure within the levelling drive. This locking mechanism preferably includes a locking wheel that is in partial mesh with a geared wheel forming part of the levelling drive. In the event of failure within the drive the locking wheel meshes to lock the position of the chair.

Abstract: The invention provides a levelling system for the chair of a stairlift, a characteristic feature of the system being the provision of a safety back-up or locking mechanism that will lock the position of the chair in the event of failure within the levelling drive. This locking mechanism preferably includes a locking wheel that is in partial mesh with a geared wheel forming part of the levelling drive. In the event of failure within the drive the locking wheel meshes to lock the position of the chair.

Abstract: A roller arrangement (20) for a stairlift carriage is described, the arrangement including a central roller set (22), and outer roller sets (24) and (26). Rollers (42), (43, 44) and (45) in the outer roller sets are mounted in yokes (48) which are mounted for independent pivotal movement, relative to one another, in two orthogonal axes. The axes of each set preferably lie in common planes.

Abstract: The invention describes an over-speed governor (21) for a stairlift (10) which not only triggers upon the carriage (12) exceeding a pre-determined speed, but also triggers in the event the chair (11) departs from the horizontal by more than a predetermined angle. The speed determining function is preferably electronic and the governor operates in both directions without adaptation. Other aspects are described including a trip speed check facility.

Abstract: A roller arrangement (20) for a stairlift carriage is described, the arrangement including a central roller set (22), and outer roller sets (24) and (26). Rollers (42), (43, 44) and (45) in the outer roller sets are mounted in yokes (48) which are mounted for independent pivotal movement, relative to one another, in two orthogonal axes. The axes of each set preferably lie in common planes.

Abstract: The present invention provides a stairlift assembly in which the stairlift chair can be tilted forward and backward to compensate for sections of the stairlift rail being slightly out of vertical. According to the invention tilting is achieved by a novel form of interface which is mounted between the chair and the stairlift carriage. Thus the tilt function need only be provided as and when needed.

Abstract: The present invention provides a stairlift rail of non-circular cross-section. The wall surfaces of the rail define a single internal cavity and the outer surface of the rail is free of additional members added to the rail in order to prevent rotation of a stairlift carriage about the rail axis.

Abstract: A stairlift includes a rail cross-section and mounting rollers which, in combination, allow a stairlift assembly to be achieved which occupies little space and has a reduced visual impact. The rollers engage rolling surfaces arranged about the outer periphery of a tubular rail. The surfaces are preferably defined by structural components of the rail and are preferably non-parallel and non-perpendicular to the stair surfaces upon which the stairlift is mounted.

Abstract: The present invention describes a formed of curved stairlift rail (12) formed by bending two sections (20a), (20b) of a relatively small diameter, standard, round tube to a mating configuration; nestling the tube sections together, one above the other; and then fixing the sections together by, for example, welding along the junctions between the tubes. The invention also describes novel forms of carriage (11) described having fixed central roller assemblies (42, 44); (65), (70), (71); and two outer, leading and trailing, roller assemblies (41, 43); (73a), (73b) which move in a substantially mirror fashion to one another when negotiating inside/outside bends, but which move together, along spaced parallel axes, when the carriage is negotiating transition bends. Spring (50), (90) are provided to bias the outer roller assemblies against the rail.

Abstract: A skate for a stairlift chair assembly (10) comprises two spaced-apart pairs of rollers, the two rollers (e.g., 27, 28) of each pair being arranged to run respectively above and below a circular section support rail (12) of the stairlift. The two rollers of each pair are rotatable about respective axes (C, D) transverse of the skate, and each roller is able to turn about a further axis (E) which intersects and is orthogonal to the rotary axes (C, D) of the pair of rollers. Each roller is constrained so that its rotary axis (C or D) remains substantially in a plane to which said further axis (E) is perpendicular.