Types of stair climbing wheelchairs

The stair climbing mechanism of star-wheel stair climbing wheelchair consists of several small wheels evenly distributed on Y-shaped, five-star shaped or cross-shaped pull rods. Each small wheel can not only rotate around its own axis, but also revolve around the central axis with a pull rod. When walking on the flat ground, the small wheels rotate, and when climbing stairs, the small wheels rotate together, thus realizing the function of climbing stairs. At present, stair climbing wheelchairs with star wheel mechanism, whether Y-shaped, cross-shaped or five-star-shaped, are prone to dislocation and slip during crawling due to the fixed track and depth of the star wheel and the different height and width of the stair steps, which has potential safety hazards. Because the domestic star-wheel stair climbing machine has no anti-skid braking function, it needs manual traction to prevent slipping when going up and down the stairs. For a wheelchair weighing nearly 50 kilograms plus human body weight, it will be difficult to control once it slips. Therefore, the safety of the stair climbing machine with star-wheel mechanism needs to be improved, but it still has a certain market in poor families because of its simple structure and low cost.

Many kinds of star-wheel stair-climbing wheelchairs have been invented at home and abroad, and most of them use two sets of star wheels composed of three, four and five small wheels. Star wheel stair-climbing wheelchair is difficult to be used on all residential stairs because of its low safety and large size (the width and height of the steps are limited), so it is difficult to popularize. This is also the main reason why the star-wheel stair-climbing wheelchair is rarely implemented and popularized, although there are many invention patents. Stepped stair climbing wheelchair has a history of nearly a hundred years abroad. After continuous evolution and improvement, it is now one of all kinds of stair climbing wheelchairs with higher safety and more complicated transmission mechanism. Its principle is to imitate the action of human climbing stairs, and it is supported alternately by two sets of supporting devices to realize the function of going up and down stairs. Because the step-by-step stair climbing wheelchair is safer than other types, it has been widely used in developed countries abroad. However, due to the complexity of its transmission mechanism, China has not yet mastered this technology. In particular, the intelligent safety alarm and anti-skid braking technology of stair climbing wheelchair with ladder support have not been mastered by domestic manufacturers. Due to the complex and highly integrated modular structure of the transmission mechanism of the stair climbing wheelchair supported by steps and the use of a large number of high-hardness lightweight materials, the cost is high. Nevertheless, out of the absolute need to ensure the safety of the disabled and the elderly, the government and the families of the disabled will give priority to safer rather than cheaper stair-climbing wheelchairs. It is believed that with the high reliability and safety of stair climbing wheelchair supported step by step, it will gradually become the mainstream stair climbing wheelchair in the future, serving more disabled and elderly people.