Belt sheave for passenger conveyor systems

A cylindrical sleeve for a sheave for a passenger conveyor system, the cylindrical sleeve comprising:

• an outer surface comprising a groove arranged to receive a belt;
• and
• an inner surface defining a cylindrical cavity;
• wherein the cylindrical sleeve comprises a polymeric material or a polymer-based composite material;
• wherein the cylindrical sleeve comprises:
• a core made of the polymeric material with a first weight percentage of fibre reinforcement;
• and
• two surface layers defining the outer surface and the inner surface, respectively, wherein the surface layers are made of the polymeric material with a second weight percentage of fibre reinforcement;
• wherein the second weight percentage of fibre reinforcement is lower than the first weight percentage of fibre reinforcement.

A cylindrical sleeve for a sheave for a passenger conveyor system, the cylindrical sleeve comprising:

• an outer surface comprising a groove arranged to receive a belt;
• and
• an inner surface defining a cylindrical cavity;
• wherein the cylindrical sleeve comprises a polymeric material or a polymer-based composite material;
• wherein the cylindrical sleeve or its a core of the cylindrical sleeve comprises:
• an outer portion wherein the fibre reinforcement is predominantly aligned with the outer surface;
• a central portion radially inward of the outer portion wherein the fibre reinforcement is predominantly arranged randomly;
• and
• an inner portion radially inward of the central portion wherein the fibre reinforcement is predominantly aligned with the inner surface.

A method of manufacturing a sheave for a passenger conveyor system, the method comprising:

• preparing a polymeric material or a polymer-based composite material for injection moulding;
• injecting the polymeric material or a polymer-based composite material into a mould, wherein the mould is arranged to produce a cylindrical sleeve comprising the polymeric material or polymer-based composite material, the cylindrical sleeve comprising:
• an outer surface comprising a groove arranged to receive a belt;
• and
• an inner surface defining a cylindrical cavity centred on the sheave axis;
• removing at least part of the mould to expose the inner surface of the cylindrical sleeve;
• and
• inserting a bearing into the cylindrical cavity while the cylindrical sleeve is at an elevated temperature, wherein the bearing includes an outer race, an inner race and one or more rolling elements therebetween, such that subsequent cooling of the cylindrical sleeve creates an engagement between an outer surface of the outer race and the inner surface of the cylindrical sleeve.

A method of manufacturing a sheave for a passenger conveyor system, the method comprising:

• introducing a material into a mould, wherein the mould is arranged to produce a cylindrical sleeve, the cylindrical sleeve comprising:
• an outer surface comprising a groove arranged to receive a belt;
• and
• an inner surface defining a cylindrical cavity centred on the sheave axis;
• removing at least part of the mould to expose the inner surface of the cylindrical sleeve;
• and
• inserting a bearing into the cylindrical cavity to form a sheave, wherein the bearing includes an outer race, an inner race and one or more rolling elements therebetween;
• wherein the outer race comprises a protrusion arranged to hold the bearing within the cylindrical cavity due to engagement between the protrusion and the inner surface of the cylindrical sleeve.