Patent Application
20110253464
1. Fields of the Invention
The present invention relates to a suspension system for an electric wheelchair, especially to an electric wheelchair that is with good stability, not easily overturned while moving over an uneven road such as a concave surface or a convex surface. Thus the safety of the user seated in the wheelchair is assured.
2. Descriptions of Related Art
Some people are paralyzed below their lower half due to serious injuries in car accidents or a stroke caused by a serious illness. Some are patients confined by illness and unable to walk. These conditions result in muscular atrophy and weakness in their legs. Thus they are unable to walk smoothly. Some are older people that move slowly because of their physical conditions that impair mobility or balance. Once these handicapped people intend to move or walk, they badly need mobility aids such as wheelchairs or crutches that help them move around. However, these mobility aid devices are operated manually. The operation of the device is not only energy consuming but the moving speed is also limited. This causes trouble and inconvenience to users.
Thus some manufactures have invented various transport vehicles such as electric scooters, electric wheelchairs, etc. By the power from electricity, handicapped people can move more easily and conveniently.
Although electric wheelchairs give handicapped people mobility, the electric wheelchairs still have some problems in use. The electric wheelchair generally includes front and rear wheels, both disposed with at least one suspension device. Moreover, rear wheels are used as main drive wheels for power transmission. During movement, the electric wheelchair is easy to slide or overturn while crossing over concave or convex terrain and this jeopardizes lives of users. Thus the stability of the electric wheelchair still needs to be improved.
Therefore it is a primary object o the present invention to provide a suspension system for an electric wheelchair so that the electric wheelchair will not overturn or slide easily no matter passing a convex surface or a concave surface on roads.
In order to achieve above objects, a suspension system for an electric wheelchair according to the present invention includes a pivot pivotally that connects a front wheel frame and a drive set frame on a front end of a frame of the electric wheelchair. Front suspension devices are positioned between the front wheel frame and the drive set frame. The front wheel frame is assembled with front wheels, the drive set frame is disposed with a drive set and a drive wheel is arranged at a power output end of the drive set. Moreover, auxiliary suspension devices are arranged between the drive set frame and the frame while a rear end of the frame is disposed with rear wheels. Thereby, according to the front suspension device arranged between the front wheel frame and the drive set frame, and the auxiliary suspension device positioned between the drive set frame and the frame, the auxiliary suspension device absorbs the force the front suspension device acted on the drive set frame. Thus the electric wheelchair is stable and is not easily overturned or slid no matter passing through an uneven road such as a concave surface or a convex surface. Therefore, the safety of the user seated in the wheelchair is assured.
The suspension system for an electric wheelchair of the present invention further includes rear suspension devices are positioned on a rear end of the frame. A rear wheel frame is pivotally connected with each of two sides of the rear end of the frame by another pivot. Rear wheels are arranged at the rear wheel frame. The rear suspension devices are positioned between the rear wheel frame and the frame. Thereby the rear suspension devices absorb shock of the rear wheels while driving through a bumpy road so as to keep stability of the electric wheelchair.
Refer to
The front suspension device 1 and the auxiliary suspension device 2 are arranged at a front end of a frame 4 of an electric wheelchair. A first pivot 41 is disposed on each of two sides of the front end of the frame 4. A front wheel frame 42 and a drive set frame 5 are pivotally connected with each other by the first pivot 41. The front wheel frame 42 is assembled with front wheels 43 while the drive set frame 5 is disposed with a drive set 51 and a drive wheel 52 is arranged at a power output end 511 of the drive set 51. Moreover, two ends of the front suspension device 1 are respectively connected with the front wheel frame 42 and the drive set frame 5 while the auxiliary suspension device 2 is disposed between the drive set frame 5 and the frame 4 of the electric wheelchair. The auxiliary suspension device 2 can be an extension spring.
Also refer to
The suspension system in electric wheelchairs of the present invention further includes rear suspension devices 3 that are disposed on a rear end of the frame 4. A rear wheel frame 45 is pivotally connected with each of two sides of the rear end of the frame 4 by a second pivot 44. Rear wheels 46 are arranged at the rear wheel frame 45. The rear suspension devices 3 are positioned between the rear wheel frame 45 and the frame 4.
Thereby refer to
In summary, the suspension system for an electric wheelchair of the present invention provides rear wheels shock absorption effects by the rear suspension device disposed between the frame and the rear wheel frame, the front suspension device arranged between the front wheel frame and the drive set frame, and the auxiliary suspension device set between the drive set frame and the frame. Moreover, the auxiliary suspension device absorbs the force the front suspension device acted on the drive set frame. Therefore, the electric wheelchair has good stability and slip-resistance, not easily overturned no matter moving through an uneven road such as a concave surface or a convex surface. Thus the safety of the user seated in the wheelchair is assured.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
