Land vehicles – Wheeled – Occupant propelled type
Reexamination Certificate
2000-09-14
2001-08-28
Johnson, Brian L. (Department: 3618)
Land vehicles
Wheeled
Occupant propelled type
C280S249000
Reexamination Certificate
active
06279934
ABSTRACT:
BACKGROUND OF THE INVENTION
Prior art manually-driven wheelchairs have been provided for two-handed operation. Typically, a chair is moveably supported by two large rear wheels and two smaller forward wheels. These chairs are manually driven by a user of the chair gripping top portions of the two large rear wheels and then pushing the top portions of the wheels in a desired direction of travel to propel the wheelchair in the desired direction. If a user desires to turn the wheelchair in a gradual change in direction, the wheel on the side of the desired direction of turn is turned more slowly than the wheel of the opposite side of the wheelchair. Sharp turns may be accomplished by only rotating one of the rear wheels while the other rear wheel is held stationary, and in some cases rotating the two rear wheels in opposite directions.
Some manually-driven wheelchairs have also been provided for single-handed operation. Such wheelchairs have provided drive axles and drive wheels which are non-rotatably connected to one of the two large rear wheels. The drive wheel is aligned an on opposite side of the wheelchair from the rear wheel to which it is non-rotatably connected by the drive axle. Some of the drive axles are not collapsible, such that they require removal for the wheelchair to collapse for storage, such as in an automobile. Such prior art wheelchairs also required tooling in order to convert the wheelchair from left-handed drive to right-handed drive operation. Others of such prior art wheel chairs did not have rigid members for rigidly connecting folding portions of the drive axles. Another disadvantage of prior art wheelchairs of this type is that the right and left side wheels cannot track in a straight line because both the right and left side wheels cannot be driven simultaneously with one hand with one stroke of a user's single arm.
SUMMARY OF THE INVENTION
A wheelchair is provided having a frame and a plurality of wheels which are rotatably mounted to the frame in supporting arrangement therewith. A drive shaft is rotatably mounted to the frame, extending transverse to the centerline of the wheelchair. A first one of the wheels is rotatably mounted to one end of the drive shaft. A second one of the wheels is fixedly mounted to the other end of the drive shaft, for rotating with the drive shaft. A remote drive wheel is fixedly mounted to the drive shaft on an opposite end of the drive shaft from the second wheel and adjacent to the first wheel. The remote drive wheel is of a slightly smaller diameter than that of the first and second wheels, preferably being about one-eight of an inch smaller in diameter. The drive shaft has a plurality of adjacent sections which are rotatably connected such that the drive shaft may be collapsed with the wheelchair frame. A coupling sleeve is slidably mounted on the drive shaft for sliding across a plurality of the adjacent sections of the drive shaft to rigidly fix the adjacent sections of the drive shaft in coaxial alignment. A dual brake control is mounted to the frame and will lock on both of the first and second wheels. The first and second wheels and the drive shaft are mounted to a drive assembly having two posts which upwardly extend for being received within tubular members of the wheelchair frame, and are latched within the tubular members by fast pins. In a second embodiment, an electronically controlled differential speed drive control unit couples a rear wheel of one side of a wheelchair to a rear wheel of the opposite side of the wheelchair, such that the relative speed of the two rear wheels are electronically controlled, preferably in response to voice, breath, suction, body or head position, or tactile commands of the user, such as those controls which are currently being used in some motor driven chairs. One such control is a head position control, which favors a turn to right if the user's head is positioned toward the left side of the wheel chair, favors to the left if the user's head is positioned to the right side of the wheelchair, and goes straight ahead if the user's head is positioned to the center of the wheelchair.
REFERENCES:
patent: 5112072 (1992-05-01), Korosue
patent: 5306035 (1994-04-01), Counts
patent: 5941547 (1999-04-01), Drake
patent: 5944131 (1999-08-01), Schaffner et al.
patent: 5988661 (1999-11-01), Garfinkle
patent: 6007082 (1999-12-01), Watwood et al.
patent: 6047980 (2000-04-01), Margherita et al.
Howison, Chauza, Thoma, Handley & Arnott LLP
Johnson Brian L.
Luby Matthew
LandOfFree
One-handed drive wheelchair having relative speed control... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with One-handed drive wheelchair having relative speed control..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and One-handed drive wheelchair having relative speed control... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2508393