Over-speed detection device for stairlifts

An over-speed detection device for a stairlift, the stairlift including a rail, and a carriage moveable along the rail, the over-speed detection device being mountable in the carriage, the over-speed detection device comprising:

• a rotary drive for contact with the rail;
• at least one weight operatively connected to said rotary drive to rotate about an axis, said at least one weight comprising a plurality of weights incorporated into a flywheel assembly, said flywheel assembly further including a hub aligned coaxially with said axis and rotatable with said weights about said axis, said hub being connected to said weights such that said hub is rotated relative to said weights as centers of mass of said weights are displaced away from said axis, wherein rotation of said weights about said axis at a determined excess speed causes said weights to be displaced away from said axis;
• a triggering facility operatively connected to said weights and being displaced as said centers of mass of said weights are displaced away from said axis, said triggering facility being displaced in a direction substantially parallel to said axis, said triggering facility comprising said hub and a trip slider in contact with said hub, said trip slider being displaceable along said axis, said trip slider and said hub having inter-engaging surfaces configured to cause axial displacement of said trip slider as said hub is rotated relative to said weights;
• and
• a transmission provided between said rotary drive and said weights to cause said weights to be rotated about said axis at a rotational speed higher than a rotational speed of said rotary drive.

A stairlift comprising:

• a stairlift rail;
• a carriage displaceable along said rail;
• a drive motor disposed within said carriage;
• a drive wheel driven by said drive motor, said drive wheel engaging said rail along a pitch line;
• and
• an over-speed governor included in said carriage, said over-speed governor having a rotary drive in contact with said rail, said over-speed governor being positioned within said carriage so that said rotary drive engages said rail at a substantial distance from said pitch line, said over-speed governor further comprising:
• at least one weight operatively connected to said rotary drive and being rotatable about an axis, said at least one weight comprising a plurality of weights incorporated into a flywheel assembly, said flywheel assembly further including a hub aligned coaxially with said axis and rotatable with said weights about said axis, said hub being connected to said weights such that said hub is rotated relative to said weights as centers of mass of said weights are displaced away from said axis, said weights having the centers of mass such that rotation of said weights about said axis above a pre-determined speed effects a displacement of said centers of mass away from said axis;
• and
• a triggering facility operatively connected to said weights and being displaced as said centers of mass are displaced away from said axis, said triggering facility being displaced in a direction substantially parallel to said axis, said triggering facility comprising said hub and a trip slider in contact with said hub, said trip slider being displaceable along said axis, said trip slider and said hub having inter-engaging surfaces configured to cause axial displacement of said trip slider as said hub is rotated relative to said weights.

A stairlift comprising:

• a stairlift rail, said rail having a negative transition bend therein;
• a carriage displaceable along said rail;
• and
• an over-speed detection device in driving contact with said rail and being operable to detect when a speed of said carriage along said rail exceeds a predetermined speed, the over-speed detection device comprising:
• a rotary drive for engagement with said rail;
• at least one weight operatively connected to said rotary drive and being rotatable about an axis, said at least one weight comprising a plurality of weights incorporated into a flywheel assembly, said flywheel assembly further including a hub aligned coaxially with said axis and rotatable with said weights about said axis, said hub being connected to said weights such that said hub is rotated relative to said weights as centers of mass of said weights are displaced away from said axis, said weights having the centers of mass such that rotation of said weights about said axis above a pre-determined speed effects a displacement of said centers of mass away from said axis;
• and
• a triggering facility operatively connected to said weights and being displaced as said centers of mass are displaced away from said axis, said triggering facility being displaced in a direction substantially parallel to said axis, said triggering facility comprising said hub and a trip slider in contact with said hub, said trip slider being displaceable along said axis, said trip slider and said hub having inter-engaging surfaces configured to cause axial displacement of said trip slider as said hub is rotated relative to said weights;
• wherein when said carriage is moving through the negative transition bend, said over-speed detection device is in driving contact with a convex surface of said rail.