Hub assembly

An assembly comprising a wheel and a demountable hub, said wheel being removably mountable upon said hub to receive rotational drive therefrom;

• said hub comprising a base member where said base member is mountable upon a driven shaft to receive said rotational drive therefrom, where said base member comprises a mounting surface for receiving said wheel for said wheel to be rotated co-axially with said shaft, and where said mounting surface comprises coupling means for coupling said rotational drive from said base member to said wheel;
• and said hub further comprising a top member, where said top member comprises a bearing member for engaging said wheel to trap said wheel between said bearing member and said base member, and a clamping member for reversably engaging said base member to urge said bearing member towards said base member, said top member being removable from said base member when said clamping member is not in engagement with said base member to allow removal of said wheel, said clamping member comprising a handle for manual depression and rotation of said clamping member relative to said bearing member;
• said clamping member comprising a first catch and said bearing member comprising a first catch receiver for mutual engagement therebetween to retain said clamping member in association with said bearing member when said clamping member is not in engagement with said base member in a first or a second primary retention position having a first angular spacing therebetween, passage between said first and second primary retention positions being achieved by depression, rotation and release under elastic restitution of said clamping member relatively to said bearing member, said elastic restitution achieved by means of a spring between said clamping member and said bearing member;
• and said clamping member further comprising a second catch for insertion into said base member if and only if said clamping member is in said first primary retention position and if said top member is in a predetermined angular relationship to said base member, said base member comprising a second catch receiver operable to receive said second catch to urge said top member towards said base member subsequently to said insertion of said second catch into said base member, in response to said passage of said clamping member between said first and said second primary retention positions, and in consequence of said elastic restitution.