Human limb manipulation device

A human limb manipulation device connectable to a power source and usable on a surface to move a human limb along a predetermined path to stretch and strengthen the limb comprising:

• a rigid frame supportable on the surface, said frame including an upwardly extending column;
• a carriage movably mounted to said column for up and down movement relative to said column;
• a first transducer connectable to the power source and connected between said frame and said carriage to selectively, reciprocatingly move said carriage relative to said column;
• and means on said carriage for supporting and retaining the limb to carry the limb with said carriage during movement of said carriage to thereby stretch and strengthen the limb;
• said first transducer including a rodless cylinder, said rodless cylinder comprising:
• a rigid, elongated, hollow barrel of non-ferrous material connected between said frame and said carriage and having first and second ends, said barrel having a first fluid inlet port at said first end and a second fluid inlet port at said second end of said barrel with each of said ports being fluidically connectable to the source of pressurized fluid;
• a piston member within said hollow barrel mounted for sliding movement between said first and second ends of said barrel in response to fluid movement into and out of said first and second inlet ports;
• a follower member outside said barrel, closely adjacent thereto and mounted for movement along and parallel to said barrel;
• one of said members including an element of ferrous material and the other of said members including a magnet so that said member with said magnet will magnetically attract and engage the remaining member to cause said follower member to move with said piston along said barrel;
• and
• said follower member being connected to said carriage so said carriage and follower member can disengage said core if excessive loading is applied to said carriage to break the magnetic attraction between said follower member and said piston member.

A human limb manipulation device connectable to a power source including a source of pressurized fluid and usable on a surface to move a human limb along a predetermined path to stretch and strengthen the limb comprising:

• a rigid frame supportable on the surface;
• a carriage movably mounted to said frame for back and forth movement relative to said frame;
• a rodless cylinder comprising:
• a rigid, elongated, hollow barrel of non-ferrous material connected between said frame and said carriage and having first and second ends, said barrel having a first fluid inlet port at said first end and a second fluid inlet port at said second end of said barrel with each of said ports being fluidically connectable to the source of pressurized fluid;
• a piston member within said hollow barrel mounted for movement between said first and second ends of said barrel in response to fluid movement into and out of said first and second inlet ports;
• a follower member outside said barrel closely adjacent thereto and mounted for movement along and parallel to said barrel;
• one of said members including an element of ferrous material and the other of said members including a magnet so that said member with said magnet will engage the remaining member to cause magnetic attraction between said follower member and said piston member to cause said members to move together along said barrel;
• said follower member being connected to said carriage so said carriage and follower member can disengage said piston member if excessive loading is applied to said carriage to break the magnetic attraction between said follower member and said piston member;
• and
• means on said carriage for supporting and retaining the limb to carry the limb with said carriage during movement of said carriage to thereby stretch and strengthen the limb.

A rodless cylinder usable with a source of pressurized fluid and an electrical power source and attachable between a base and a load to move the load along a path and disengage from the load when a predetermined opposition force is encountered comprising:

• a rigid, elongated, hollow barrel of nonferrous material connectable to the base and having first and second ends, said barrel having a first fluid inlet port at said first end a second fluid inlet port at said second end of said barrel with each of said ports being selectively, fluidically connectable to the pressurized fluid;
• a piston member within said hollow barrel and mounted for movement between said first and second ends of said barrel in response to fluid movement into and out of said first and second inlet ports, said piston member including an element formed of ferrous material;
• a follower member outside said barrel, closely adjacent thereto and mounted for movement along and parallel to said barrel;
• said follower member including an electromagnet closely confronting said barrel and connectable to the electrical power source for selective energization so that during energization said follower member will magnetically engage said piston member with a predetermined level of magnetic attraction to cause said follower member to lock onto and retain said piston member and move along said barrel with said piston member, and said follower member can disengage said piston member when the predetermined opposition force is applied to said follower member to break the magnetic attraction between said follower member and said piston member and also when said electromagnet is de-energized.