Popular Science I Electric wheelchair category, composition

With the intensification of the aging society, barrier-free travel aids have gradually entered the lives of many elderly people, and electric wheelchairs have also become a new type of transportation that is very common on the road.

There are many types of electric wheelchairs, and the price ranges from more than 1,000 yuan to 10,000 yuan. At present, there are more than 100 kinds of brands on the market, with different configurations, materials and quality.

How to choose the right electric wheelchair for you, how to avoid detours when buying electric wheelchairs, and not fall into the “pit”?

First, learn about electric wheelchairs.


01 Electric Wheelchair Category

Category 1: Indoor Electric Wheelchair

The speed is required to be controlled at 4.5km/h. Generally, the size of this type is small and the power of the motor is low, which also determines that the battery life of this type will not be too far. The user mainly completes some daily life independently indoors. In the product model name, it is represented by a capital letter N.

The second category: outdoor electric wheelchair

The speed is required to be controlled at 6km/h. The general volume of this type is relatively large, the body structure is thicker than the first type, the battery capacity is also larger, and the battery life is longer. In the product model name, it is represented by a capital letter W.

The third category: road type electric wheelchair

The speed is too fast, and the maximum speed is required not to exceed 15km/h. The motor often uses high power, and the tires are also thickened and enlarged. Generally, such vehicles are equipped with outdoor lighting and steering indicators to ensure the safety of road driving. In the name of the product model, it is represented by the capital letter L in Chinese Pinyin.

On December 31, 2012, China issued the national standard GB/T12996-2012 on electric wheelchairs. For indoor, outdoor and road electric wheelchairs, the model nomenclature, surface requirements, assembly requirements, dimensions and performance requirements , strength requirements, flame retardancy, climate, power and control system requirements and corresponding test methods and inspection rules, documentation and information release, marking and packaging requirements for wheelchairs are all explained and required.

Most consumers don’t know much about the electric wheelchair, a medical device product, and they just judge the quality by simply looking at the appearance or the sales volume of the e-commerce platform until they place an order. However, many users will find many unsatisfactory places after receiving the goods.

When most people buy their first electric wheelchair, they usually only start from the point of view of portability, and consider the lightness, foldability, and storage in the trunk, etc., and do not consider the problem from the perspective of the daily needs of users.image2

The comfort, power, battery life of the electric wheelchair, as well as the stability and controllability of the whole vehicle system, are often a few months later, after a period of use, the family will get feedback.

Many users will also consider purchasing electric wheelchairs for the second time. After the first experience, they can better understand their needs and find electric wheelchairs that are more suitable for them. Most of the second purchases are outdoor models. with road type.

02 Structure of electric wheelchair

The electric wheelchair is mainly composed of the following parts: the main frame, the controller, the motor, the battery, and other accessories such as the seat back pad.

Next, let’s take a look at each part of the accessories~

1. Main frame

The main frame determines the structural design, external width, seat width, external height, backrest height and function of the electric wheelchair.

The material can be divided into steel pipe, aluminum alloy, aviation titanium alloy, and some high-end models begin to use carbon fiber material. Most of the common materials in the market are steel pipes and aluminum alloys.

The cost of steel pipe material is relatively low, and the load-bearing is not bad. The disadvantage is that it is bulky, easy to rust and corrode in water and humid environments, and has a short service life.

Most mainstream electric wheelchairs use aluminum alloys, which are lighter than steel pipes and have stronger corrosion resistance.

The material strength, lightness and corrosion resistance of aviation titanium alloy are better than the first two. However, due to the cost of materials, it is currently mainly used in high-end and portable electric wheelchairs, and the price is also more expensive.

In addition to the material of the main frame, the details of other components of the car body and the welding process should also be observed, such as: all accessories materials, material thickness, whether the details are rough, whether the welding points are symmetrical, and the more densely arranged the welding points, the better. The arrangement rules similar to fish scales are the best, it is also called fish scale welding in the industry, and this process is the strongest. If the welding part is uneven or there is leakage of welding, it will gradually appear a safety hazard with the use of time.

The welding process is an important link to observe whether a product is produced by a large factory, whether it is serious and responsible, and producing products with high quality and quantity.image3

2. Controller

The controller is the core part of the electric wheelchair, just like the steering wheel of a car, its quality directly determines the controllability and service life of the electric wheelchair. The controller is generally divided into: upper controller and lower controller.

Most imported brand controllers are composed of upper and lower controllers, and most domestic brands only have upper controllers. The most widely used imported controller brands are Dynamic Controls and PG Drives Technology. The quality of imported products is better than that of domestic products, and the cost and price are also higher. They are generally equipped on medium and high-end electric wheelchairs.

To simply check the quality of the controller, you can try the following two operations:

1) Turn on the power switch, push the controller, and feel whether the start is smooth; release the controller, and feel whether the car stops immediately after the sudden stop.

2) Control the rotating car on the spot and feel whether the steering is smooth and flexible.

3. Motor

This is the core component of the driver. According to the way of power transmission, it is mainly divided into brush motor (also called worm gear motor) and brushless motor (also called hub motor), and there is also a crawler motor (similar to the tractor in the early years, driven by a belt).

The advantages of the brushed motor (turbine worm motor) are that the torque is large, the torque is large, and the driving force is strong. It is easy to go up some small slopes, and the start and stop are relatively stable. The disadvantage is that the conversion rate of the battery is low, that is, it is relatively expensive, so the wheelchair using this motor is often equipped with a large-capacity battery. The weight of the whole vehicle using this motor is about 50-200 catties.

The advantages of brushless motor (wheel hub motor) are power saving and high conversion rate of electricity. The battery equipped with this motor does not need to be particularly large, which can reduce the weight of the vehicle. Most of the vehicle using this motor weighs about 50 pounds.

The power transmission of the crawler motor is too long, it is relatively expensive, the power is weak, and the cost is low. At present, only a few manufacturers are using this motor.

4. Battery

It is well known that there are lead-acid batteries and lithium batteries. Whether it is a lead-acid battery or a lithium battery, attention should be paid to maintenance and maintenance. When the electric wheelchair is idle for a long time, it should be charged and maintained regularly. Generally, it is recommended to charge the battery at least once every 14 days, because even if it is not used, the battery will slowly power consumption.

When comparing the two batteries, most people agree that lead-acid batteries are inferior to lithium batteries. What’s so good about lithium batteries? The first is lighter, and the second has a longer service life. Most of the standard configuration of lightweight electric wheelchairs are lithium batteries, and the price is also higher.

The voltage of the electric wheelchair is generally 24v, and the capacity unit of the battery is AH. Under the same capacity, the lithium battery is better than the lead-acid battery. However, most domestic lithium batteries are around 10AH, and some 6AH batteries meet the aviation boarding standard, while most lead-acid batteries start at 20AH, and there are 35AH, 55AH, 100AH, etc., so in terms of battery life, lead-acid batteries Stronger than lithium batteries.

The 20AH lead-acid battery lasts about 20 kilometers, the 35AH lead-acid battery lasts about 30 kilometers, and the 50AH lead-acid battery lasts about 40 kilometers.

Lithium batteries are currently mainly used in portable electric wheelchairs, and are relatively inferior to lead-acid batteries in terms of battery life. The cost of battery replacement in the later stage is also higher than that of lead-acid batteries.

5. The braking system is divided into electromagnetic braking and resistance braking

To judge the quality of the brakes, we can test the release of the controller on the slope to see if it will slide and feel the length of the braking buffer distance. The short braking distance is relatively more sensitive and safer.

The electromagnetic brake can also use the magnetic brake when the battery is dead, which is relatively safer.

6. Wheelchair seat back cushion

At present, most manufacturers are equipped with double-layer back pads, which are breathable

flatness of the fabric, the tension of the fabric, the details of the wiring, the fineness of the craftsmanship, etc. If you look closely, you will find the gap.

Post time: Sep-20-2022