Stair-climbing machine and resistance controlling device thereof

Abstract

A resistance controlling device includes a flywheel and a damper unit. The damper unit includes a damper rack and a plurality of permanent magnets disposed on the damper rack. The damper rack is movable between a high-resistance position, where the damper rack is proximate to the flywheel, and a low-resistance position, where the damper rack is distal from the flywheel. When the flywheel is driven to rotate as the damper rack is in the high-resistance position, the permanent magnets exert a first resistance force on the flywheel. When the flywheel is driven to rotate as the damper rack is in the low-resistance position, the permanent magnets exert a second resistance force weaker than the first resistance force on the flywheel. A stair-climbing machine includes a base frame unit, a transmission device, a control device and the abovementioned resistance controlling device.

What is claimed is: 
     
         1 . A resistance controlling device being adapted to be installed to a base frame unit of a stair-climbing machine, said resistance controlling device comprising:
 a flywheel that is made of metal, that includes an axle extending in an axial direction along an axis and adapted to be mounted in the base frame unit of the stair-climbing machine, and that is rotatable about the axis; and   a damper unit that is adapted to be mounted in the base frame unit of the stair-climbing machine, and that includes a damper rack and a plurality of permanent magnets disposed on said damper rack;   wherein, said damper rack is movable between a high-resistance position, where said damper rack is proximate to said flywheel, and a low-resistance position, where said damper rack is distal from said flywheel;   wherein, when said flywheel is driven to rotate as said damper rack is in the high-resistance position, said plurality of permanent magnets exert a first resistance force on said flywheel; and   wherein, when said flywheel is driven to rotate as said damper rack is in the low-resistance position, said plurality of permanent magnets exert a second resistance force on said flywheel, the second resistance force being weaker than the first resistance force.   
     
     
         2 . The resistance controlling device as claimed in  claim 1 , wherein:
 said damper rack has a fixed end and a pivot end that are opposite to each other;   said damper rack includes a pivot shaft that is disposed at said fixed end, and that is adapted to be mounted to the base frame unit of the stair-climbing machine, so that said pivot end is adapted to be pivotable relative to the base frame unit of the stair-climbing machine, with said pivot shaft serving as a pivot, to convert said damper rack between the high-resistance position and the low-resistance position;   when said damper rack is in the high-resistance position, said pivot end is proximate to said flywheel;   when said damper rack is in the low-resistance position, said pivot end is distal from said flywheel; and   a portion of said flywheel that overlaps said plurality of permanent magnets in the axial direction when said damper rack is in the high-resistance position is larger than a portion of said flywheel that overlaps said plurality of permanent magnets in the axial direction when said damper rack is in the low-resistance position.   
     
     
         3 . The resistance controlling device as claimed in  claim 2 , wherein:
 said damper rack further includes a rack body that extends from said fixed end to said pivot end, said pivot shaft extending through said rack body so that said rack body is pivotable about said pivot shaft; and   said damper rack further includes two magnet mount plates that are disposed at said pivot end and that are spaced apart from each other in the axial direction, said flywheel being disposed between said magnet mount plates, said plurality of permanent magnets being disposed on said magnet mount plates.   
     
     
         4 . The resistance controlling device as claimed in  claim 3 , wherein each of said magnet mount plates has a surface facing said flywheel, said plurality of permanent magnets being disposed on said surfaces of said magnet mount plates. 
     
     
         5 . The resistance controlling device as claimed in  claim 2 , wherein:
 said damper unit further includes a motor that is fixed to said pivot end of said damper rack, a fixed member that is adapted to be mounted to the base frame unit of the stair-climbing machine, and a screw rod that interconnects said motor and said fixed member;   said motor is operable for driving said screw rod to spin and drive said motor to move towards or away from said fixed member;   when said motor is driven to move towards said fixed member, said damper rack is driven to move to the low-resistance position; and   when said motor is driven to move away from said fixed member, said damper rack is driven to move to the high-resistance position.   
     
     
         6 . A stair-climbing machine comprising:
 a base frame unit;   a transmission device that includes
 a transmission unit mounted to said base frame unit, and 
 a stair unit disposed around said transmission unit, being movable relative to said base frame unit, and being operable for driving operation of said transmission unit; 
   a control device that is mounted to said base frame unit and that is operable for outputting a control signal; and   said resistance controlling device as claimed in  claim 1 , said flywheel of said resistance controlling device being connected to said transmission unit, said damper unit of said resistance controlling device being mounted to said base frame unit and being signally connected to said control device;   wherein said damper unit receives the control signal, and moves said damper rack of said damper unit between the high-resistance position and the low-resistance position in accordance to the control signal; and   wherein, said stair unit is operable for driving, via said transmission unit, said flywheel to rotate.   
     
     
         7 . The stair-climbing machine as claimed in  claim 6 , wherein:
 said damper rack has
 a fixed end and a pivot end that are opposite to each other; 
 said damper rack includes a pivot shaft that is disposed at said fixed end, and that is mounted to said base frame unit, so that said pivot end is pivotable relative to said base frame unit, with said pivot shaft serving as a pivot, to convert said damper rack between the high-resistance position and the low-resistance position; 
   when said damper rack is in the high-resistance position, said pivot end is proximate to said flywheel;   when said damper rack is in the low-resistance position, said pivot end is distal from said flywheel; and   a portion of said flywheel that overlaps said plurality of permanent magnets in the axial direction when said damper rack is in the high-resistance position is larger than a portion of said flywheel that overlaps said plurality of permanent magnets in the axial direction when said damper rack is in the low-resistance position.   
     
     
         8 . The stair-climbing machine as claimed in  claim 7 , wherein:
 said damper rack further includes a rack body that extends from said fixed end to said pivot end, said pivot shaft extending through said rack body so that said rack body is pivotable about said pivot shaft; and   said damper rack further includes two magnet mount plates that are disposed at said pivot end and that are spaced apart from each other in the axial direction, said flywheel being disposed between said magnet mount plates, said plurality of permanent magnets being disposed on said magnet mount plates.   
     
     
         9 . The stair-climbing machine as claimed in  claim 8 , wherein each of said magnet mount plates has a surface facing said flywheel, said plurality of permanent magnets being disposed on said surfaces of said magnet mount plates. 
     
     
         10 . The stair-climbing machine as claimed in  claim 7 , wherein
 said damper unit further includes a motor that is fixed to said pivot end of said damper rack, a fixed member that is mounted to said base frame unit, and a screw rod that interconnects said motor and said fixed member;   said motor is operable for driving said screw rod to spin and drive said motor to move towards or away from said fixed member;   when said motor is driven to move towards said fixed member, said damper rack is driven to move to the low-resistance position; and   when said motor is driven to move away from said fixed member, said damper rack is driven to move to the high-resistance position.