Although the lifting table and chair can be adjusted freely, its structure is still very simple. Lifting tables and chairs are mainly made of steel and wood structures. The desktop is made of melamine, the legs are made of steel, and the stools are mostly made of steel and wood. There are also related parts on the desk and stool to adjust the height. Some lifting tables and chairs are made of plastic, but the firmness of this kind of plastic lifting tables and chairs is not very high.
Second, the advantages and disadvantages of students lifting tables and chairs
1. Advantages of lifting tables and chairs
The advantage of lifting chairs and tables is very obvious, that is, the height of tables and chairs can be adjusted manually, which can be used by students of different heights. With a good "mount", students' classroom state will be much better, and it is not easy to cause fatigue to students, nor will it cause myopia or other diseases.
2. Disadvantages of lifting tables and chairs
The lifting tables and chairs are made of steel and wood, so the structure is complicated, and it is a bit troublesome for students to clean the classroom. Moreover, because the lifting tables and chairs cannot be adjusted at will, corresponding tools (such as wrenches) must be used, resulting in many lifting tables and chairs becoming fixed desks.
Iii. Matters needing attention in purchasing lifting tables and chairs
The choice of lifting tables and chairs is very important. The first choice is safety. Lifting tables and chairs must be firm and cannot be staggered. The materials of lifting tables and chairs must be environmentally friendly, students are the future of the motherland, and the flowers of the motherland must be well protected. The use of environmentally friendly materials is beneficial to students' health. The size of lifting tables and chairs is also very important, and the size must conform to the principles of popularization and ergonomics; Finally, the colors of the lifting tables and chairs should be coordinated, and it is best to choose elegant colors instead of fighting.
1, to ensure safety
The safety of children's desks and chairs must be the top priority. It is best to choose a desk with smooth lines and rounded or curved edges. Besides, you should do a delicate surface treatment. When buying, you can shake the desk vigorously to see if its structure is stable. If you feel loose and shaky, don't choose to avoid potential safety hazards later.
2, high cost performance
The material of tables and chairs needs to be clear, which is directly related to the price and quality of desks. Generally, the legs of tables and chairs are made of steel and wood, and the surface of desktop chairs is made of wood. If pine is used as the desktop material, it will be more environmentally friendly, but its performance is relatively poor. Korean pine is light and soft with moderate strength, while beech is hard and straight. Check the common sense of wood online in advance, make a basic understanding, and then make a choice as needed.
3, accurate and appropriate
The size of students' desks and chairs should be accurate, and should be selected according to the classroom area and seat discharge. Also pay attention to the age of students who use desks and chairs and choose the most suitable size. Moreover, the style of desks and chairs should be appropriate and coordinated with the overall style of schools and classrooms. The color is simple, which can ensure the psychological calm and stability when studying.
Step 4 pay attention to details
For tables and chairs, we must pay attention to the details. When buying, carefully observe whether there are defects and cracks. If there is a scar on the front and a scar on the back in the same position, then this scar is a dead knot and will fall off after a long time. So, don't buy this kind of defective desk. In addition, it depends on whether the various parts of the desk are firmly connected, whether the drawers and doors are open and closed freely, and whether the screws are firm.
Fourth, the lifting principle of lifting tables and chairs
1, pneumatic chair principle
Pneumatic lifting chair is a new type of chair. There is a cylinder in the lifting chair, and the piston rod in the cylinder moves up and down to control the lifting of the swivel chair.
2. Principle of hydraulic lifting chair
The hydraulic jack in the key position of the hydraulic lifting chair is manually driven by the hydraulic pump, which is driven by the hydraulic system and uses the cylinder or piston as the jack. Hydraulic jacks can be divided into integral type and separated type. The integral pump and the hydraulic cylinder are connected into a whole; The separation pump is separated from the hydraulic cylinder and connected with a high-pressure hose in the middle.
3. Principle of spiral lifting chair
Its basic principle can be summarized as "tightening". The position of the chair is locked by the self-locking of the screw pair, which has simple structure, high safety and generally no potential safety hazard. It should be noted that the bolts and nuts of the spiral lift chair are easy to rust, so the durability is not very good. Moreover, after using for a long time, the screw connection part is easy to loosen due to wear and other reasons.
4. Principle of positioning lifting chair
The legs of this lifting chair are composed of two parts, only two parts are used and then connected by screws, which is relatively safe. However, because it is connected by screws, the screws must be screwed before and after each lifting, so the operation is not very convenient. Moreover, this kind of lifting chair can only be lifted in a fixed position, and its flexibility is not very good.
5. Principle of electric lifting chair
Linear drive electric push rod lifting device Electric push rod lifting column is a new type of linear lifting actuator, which is mainly composed of motor, push rod and control device, and can realize remote control and centralized control. The four-sided guide structure design and DC electric push rod drive are adopted, so that the electric push rod lifting column has the advantages of stable and silent lifting.