Machine element or mechanism – Control lever and linkage systems – Elements
Reexamination Certificate
1998-08-06
2001-02-06
Green, Mary Ann (Department: 3682)
Machine element or mechanism
Control lever and linkage systems
Elements
C280S304100, C016S430000
Reexamination Certificate
active
06182529
ABSTRACT:
FIELD OF THE INVENTION
The field of the invention is to provide an improved handlebar for manipulating non-motorized wheelchairs or similar vehicles. The handlebar also functions as a brace to protect collapsible wheelchairs against unintended collapse.
BACKGROUND ART
Most existing wheelchairs have two parallel, rearwardly-directed handles which are (a) separated by a distance equal to the width of the wheelchair (18 to 24 inches), and (b) parallel to the ground. This paired-handle design requires use of two hands for control of the wheelchair, making it difficult for a person to push a wheelchair with only one free hand. This is not a minor problem within a hospital environment, as sometimes medical or other equipment must be moved along with the wheelchair. Either two persons must then be used to move a single person in a wheelchair, or one person must push the wheelchair with one hand, and manipulate the equipment with the other, which is awkward and at times unsafe. Outside of the hospital environment, one may be in a situation where one must push a wheelchair-bound person with one hand, while carrying an umbrella or holding a parcel with the other.
Additionally, manual manipulation of a wheelchair using the standard, rearwardly-directed handles is ergonomically unsound or inefficient. The person pushing the wheelchair is forced to (a) grip the handle tightly with the hand, (b) orient and lock the wrist in an ulnar-deviated position, and (c) orient the forearm in a supinated position. These positions are uncomfortable, tiring, and drain strength.
There is a great need for wheelchair handlebars that allow a person pushing the wheelchair to do so in an ergonomically correct manner, grasping the handlebar loosely with either hand, or with both hands, without any uncomfortable twisting and/or bending of the forearms and wrists. To date, no completely satisfactory design has been proposed.
A number of wheelchair handlebars have been developed, such as those shown in U.S. Pat. Nos. 5,290,055 and 5,044,650 (see
FIG. 1
a
).
These usually connect the handles with a straight bar that does relieve the strain on the hands and forearms, but do little to relieve the strain caused by ulnar deviated positioning of the wrists. Another handlebar design found in U.S. Pat. No. 4,872,697 (see
FIG. 1
b
) is designed to allow a person to push a wheelchair with one hand. The parallel handles are connected with a crosspiece, and a single handgrip, or grip station, projects horizontally from the crosspiece. The grip station is substantially parallel to the handles, and provides no significant ergonomic advantage over the original handles.
Also, these handlebars are usually fitted to the existing handles by means of screw clamps or other forms of clamps. These clamps have the drawback that, if the clamps are not securely tightened or if they are accidentally loosened, the handlebar may come loose from the handles. These clamps often consist of multiple parts and project significantly out of the plane of the handles. They can also be time consuming to use. In a few cases, the crosspiece of the handlebar cannot be comfortably gripped due to the clamping mechanism. As previously stated, the grip station in the handlebar of
FIG. 1
a
is ergonomically very poor. Unfortunately, the crosspiece to which the grip station is secured cannot be comfortably gripped by a user either due to the bulky and complicated clamping mechanism.
SUMMARY OF THE INVENTION
It is a first object of the invention to provide an improved, ergonomically correct handlebar for wheelchairs or similar articles having two substantially parallel tubular handles. The handlebar should be adapted to be fitted to the existing handles and securely locked into position.
It is a second object of the invention to provide a novel mechanism for locking a handlebar onto the existing handles of a wheelchair or similar vehicle.
It is a third object of the invention to provide a handlebar for a collapsible wheelchair which may be used to brace the wheelchair against unintended collapse, yet which may be quickly removed and conveniently stowed when the wheelchair is collapsed.
It is a fourth object of the invention to provide a method of adapting existing wheelchairs so that they may receive the handlebar of the invention, and an apparatus for use in carrying out this method.
These objects are achieved with the handlebar of the present invention. The handlebar is a tube having a two parallel end portions which slide over the existing handles of the wheelchair. The parallel end portions are connected by a central portion having multiple grip stations. Two ergonomically designed first grip stations are provided, one oriented so as to be gripped by the right hand and one oriented so as to be gripped by the left hand. The first grip stations are mirror images of each other. Further grip stations may be provided.
The handlebar is locked into position by two locking mechanisms, one positioned in each preexisting wheelchair handle. Each locking mechanism comprises an outwardly biased button which protrudes through correspondingly positioned holes in the wall of the wheelchair handle and the handlebar.
The grip sections on the central portion of the handlebar are positioned so that a user may grip the handlebar comfortably, without having to exert strain on his wrist, or bend his wrist uncomfortably.
Retrofitting of existing wheelchairs is easy, requiring merely that properly positioned holes be drilled in the preexisting wheelchair handles and that locking mechanisms be positioned in each handle.
While the handlebar described herein is primarily intended for a wheelchair, it is not limited to wheelchairs. Specifically, handlebars having a similar structure may be used with any manually operated vehicle having rearwardly directed handlebars, including wheelbarrows, shopping carts, carriages or strollers, and bicycles.
REFERENCES:
patent: D. 27660 (1897-09-01), Anschuetz
patent: D. 342046 (1993-12-01), Chen
patent: D. 390168 (1998-02-01), Haut
patent: 4386790 (1983-06-01), Kassai
patent: 4708357 (1987-11-01), Sederbaum
patent: 4872697 (1989-10-01), Berkowitz
patent: 4896897 (1990-01-01), Wilhelm
patent: 4964648 (1990-10-01), Berkowitz
patent: 5044650 (1991-09-01), Eberle, Jr.
patent: 5290055 (1994-03-01), Treat, Jr.
patent: 5758548 (1998-07-01), Smith
patent: 5788252 (1998-08-01), Happ et al.
patent: 5915712 (1999-06-01), Stephenson et al.
patent: 5974627 (1999-11-01), Huang
Undated Advertising Material—CASBAR—Cites Previously Disclosed US 5240055.
Green Mary Ann
Yeager Arthur G.
LandOfFree
Handlebar for wheelchairs does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Handlebar for wheelchairs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Handlebar for wheelchairs will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2611345