Automatic wheelchair brake system and wheelchair including same

An automatically engageable and releasable brake apparatus adaptable to be attached to a wheelchair, said brake apparatus comprising:

• a connection mechanism adapted to be attached to a portion of a frame of the wheelchair;
• a seat actuation member adapted to be positioned in communication with a seat of the wheelchair, said seat actuation member comprising a first fluid cell having a first volume and including a plurality of fluid chambers in fluid communication with one another;
• a brake actuating member in fluid communication with said seat actuation member and defining a closed fluid system therewith, said brake actuating member comprising a second fluid cell having a second volume, wherein said first fluid cell is in fluid communication with said second fluid cell via a conduit having a third volume, and wherein said first fluid cell, said second fluid cell and said conduit define said closed fluid system;
• a brake shaft member in communication with said brake actuating member, said brake shaft member extending from a first end thereof to an opposed second end thereof, and positioned to extend substantially downwardly from a portion of said connection mechanism proximate said first end of said shaft member;
• and
• a friction member positioned proximate said second end of said brake shaft member and adapted to contact a surface on which the wheelchair is located;
• wherein a volume of fluid in said closed fluid system is less than a total volume of said closed fluid system, and wherein occupational ingress into the wheelchair actuates said seat actuation member to cause fluid flow from said seat actuation member to said brake actuating member, which actuates said brake actuating member and causes said brake shaft member to move such that said friction member substantially contemporaneously moves from a first position in substantial contact with the surface on which the wheelchair is located to a second position spaced a distance above the surface on which the wheelchair is located.

An automatically engageable and releasable brake apparatus adaptable to be attached to a wheelchair, said brake apparatus comprising:

• a seat actuation member comprising a first fluid cell having a first volume and including a plurality of fluid chambers in fluid communication with one another;
• a brake actuating member in fluid communication with said seat actuation member and defining a closed fluid system therewith, said brake actuating member comprising a second fluid cell having a second volume, wherein said first fluid cell is in fluid communication with said second fluid cell via a conduit having a third volume, and wherein said first fluid cell, said second fluid cell and said conduit define said closed fluid system;
• and
• a brake member in communication with said brake actuating member;
• wherein actuation of said seat actuation member activates said brake actuating member which causes said brake member to move from a first position which prevents any significant rearward motion of the wheelchair to a second position which allows substantially unrestricted rearward motion of the wheelchair.

A wheelchair comprising:

• a frame;
• a seat member incorporated into and substantially supported by said frame;
• a wheel assembly having a plurality of first wheels rotatably connected proximate a front end of said frame, and a plurality of second wheels rotatably connected proximate a rear portion of said frame;
• and
• an automatically engageable and releasable brake apparatus attached to said rear portion of said frame, said brake apparatus comprising:
• a seat actuation member comprising a first fluid cell having a first volume and including a plurality of fluid chambers in fluid communication with one another,
• a brake actuating member in fluid communication with said seat actuation member and defining a closed fluid system therewith, said brake actuating member comprising a second fluid cell having a second volume, wherein said first fluid cell is in fluid communication with said second fluid cell via a conduit having a third volume, and wherein said first fluid cell, said second fluid cell and said conduit define said closed fluid system, and
• a brake member in communication with said brake actuating member;
• wherein actuation of said seat actuation member activates said brake actuating member which causes said brake member to move from a first position which prevents any significant rearward motion of said wheelchair to a second position which allows substantially unrestricted rearward motion of said wheelchair.