Numerous devices for braking and preventing wheelchairs of various types of construction from moving are known, and many of these devices are the subject of United States patents. The patents to Herron, U.S. Pat. No. 4,560,181, and Lemarie, U.S. Pat. No. 4,538,826, relate to or disclose wheelchair braking devices wherein caliper-type brake attachments are provided which urge against the wheelchair wheel rim in order to control the movement of the wheel. In the Herron patent, the brake mechanism includes a handbrake mounted on a lever arm which is coupled through a brake cable to a brake assembly. There appears to be no specific description of how the brake assembly is mounted to the frame. The patent to Lemarie includes a type of propelling mechanism whereby a caliper-type arrangement, including engagement pads, contacts the rim of the wheelchair wheel in order to aid in propelling the wheel.
Additional patents to DeWoody et al. and Fought et al., U.S. Pat. Nos. 4,560,033 and 4,887,830, respectively, disclose more conventional types of braking apparatus for wheelchairs. In each of these patents, the braking mechanisms includes a braking member which urges directly against the tire, rather than the rim, to prevent movement.
Wheelchair brakes are also disclosed in the patents to Marshall, U.S. Pat. No. 3,529,700; Hammack, U.S. Pat. No. 2,426,451; Wierwille, U.S. Pat. No. 4,384,732; Minnebraker et al., U.S. Pat. No. 4,570,756; Kulik, U.S. Pat. No. 4,852,697; and Knoche, U.S. Pat. No. 4,350,227. All of these patents disclose braking devices for wheelchairs wherein braking pressure is applied directly to the tire rather than to the wheel rim.
Of particular interest is the patent to Kawecki, U.S. Pat. No. 4,204,588, wherein a wheelchair braking apparatus which incorporates a caliper brake as the braking member is disclosed. That Kawecki invention includes a braking device which locks the primary wheels so that when an individual gets out of the wheelchair the braking mechanism can be actuated to prevent the chair from rolling backward. The specific wheelchair disclosed in the Kawecki patent includes a pair of crossbraces to which are attached a bracket consisting of an upright portion and a horizontal portion. The vertical or upright portion spans the distance between the crossbraces and is provided with holes at each end so that U-bolts can pass therethrough to attach the bracket to the brace members. The horizontal portion is preferably welded to the upright portion and extends outwardly therefrom beyond the primary wheels and parallel to the axis which mounts the primary wheels onto the wheelchair. A vertical pivot point is provided on the horizontal portion of the bracket directly in line with and proximate to the primary wheel. A conventional two-arm caliper brake having a pair of brake pads is affixed to the pivot point. The brake pads are connected to a control wire. When the wire is pulled, the brake pads come into contact with the rim of the wheel. The wire is controlled by what is termed a remotely located actuating device which includes a pivotal lever arm connected at one end to the wire. Forcing the pivot arm downwardly causes the wire to pull and ultimately urges the brake pads against the wheel rim.
During recent years with the advent of lighter and stronger tubular materials, wheelchairs have undergone important technological improvements. No longer is it necessary for wheelchairs to literally resemble "chairs on wheels" with rigid vertical frames and vertical wheels with armrests and handles for pushing. Wheelchairs today are lighter, more maneuverable and reflect the increased desire of many wheelchair-bound persons to be able to get about as independently as possible.
While the wheelchair frame and materials have undergone an important evolution, little has been done to improve the ability of the wheelchair user to stop the motion of the wheelchair and maintain a fixed position.
One of the most used devices for stopping and securing the wheelchair is a brake device similar to that shown in the Minnebraker et al. patent, U.S. Pat. No. 4,570,756, where a lever arm is provided which urges a braking member into contact with the tread of the wheelchair tire. While a popular device, this brake causes unnecessary wear to the tire tread, it is not totally effective in holding the wheelchair on sloped surfaces and becomes almost unusable when the tire is wet. The device is only applied to one wheel, so if stopping action is desired on both wheels of the wheelchair, two devices must be applied and engaged by using two hands, which sometimes simply is not possible.
Furthermore, many of the former types of braking devices were developed for use with wheelchairs with armrests and are designed to be attached to the armrests. Many of the newer, lightweight model wheelchairs do not even have arms.
In this regard, it would be beneficial if a wheelchair brake were available which will overcome these and other deficiencies in the prior art types of wheelchair braking devices.
USPTO Backgrounds
USPTO Backgrounds