The selection of various indexes and materials of the pulley is to minimize the selection principle of raw materials, workable technology and the lowest cost on the premise that it can meet the requirements of use.
Advantage：
The advantages of pulley drive include: belt pulley transfer energy to ease load impact, pulley drive running smoothly, low noise, low vibration; belt pulley transmission is simple, easy to adjust; belt pulley transmission for pulley manufacturing and installation accuracy is not like meshing transmission strict; skin belt wheel drive with overload protection function; The two axle center distance of belt drive is larger. Belt drive has the disadvantages of: the belt pulley transmission has elastic sliding and skidding, the transmission efficiency is low and the accurate transmission ratio can not be maintained; when the belt pulley transmission passes the same large circumference force, the contour size and the pressure on the shaft are larger than the meshing transmission; the belt wheel transmission belt has a shorter life span. The diameters and diameters of pulley of all kinds of mechanical equipment are matched with their own pulley according to the speed reduction ratio, and they are designed according to the working speed and the speed of the motor. Working speed / motor speed = drive wheel diameter / moving wheel diameter *0.98 (sliding coefficient), such as using steel as the material of the pulley, the required line speed is not higher than 40m/s, such as the use of cast iron material, the demand line speed is not higher than 35m/s, motor speed and pulley diameter conversion ratio, speed ratio = output speed: input speed = load pulley circle circle. Diameter: circular diameter of motor pulley. The diameter of the circle and the reference diameter are the same, the diameter -2h= nodal circle diameter, the H is the base line trough depth, the different types of V band h are different, Y Z A B C D E, the base line slot depth is h=1.6 22.75 3.5 4.8 8.1 9.6 respectively. The circle diameter of the belt pulley is the theoretical diameter of the belt pulley, which is a bit like the diameter of the dividing circle of the gear. Generally, it is expressed by PD. The outer circle is generally expressed by OD. The conversion formula of the different grooved nodal circle and the outer circle is different. Generally, we can easily measure the outer circle of the pulley, and calculate the nodal circle.SPZ:OD=PD+4; SPA:OD=PD+5. 5; SPB:OD=PD+7; SPC:OD=PD+9.6. The minimum outer diameter of A or SPA is 80mm. If it is less than this size, especially in high speed, the belt is prone to delamination and cracks at the bottom. SPZ belt, small wheel is not less than 63mm. At the same time, attention should be paid to the techniques and tension of the belt installation, too easy to skid, too big to damage the belt and bearings.
Specifications：
The specifications of the triangular belt are divided by the size of the back width (top width) and high (thick). According to the different dimensions of the back width (top width) and high (thick), the national standard stipulates the O, A, B, C, D, E, etc. of the triangle belt, and the width, top width and height of each type of triangle belt are different, so the belt pulley All kinds of grooves must be made according to the shape of the triangle belt. These different grooved pulleys decide the O pulley, A pulley, B pulley, C belt pulley, D pulley, E belt pulley and so on.
Model：
O A B C D E 3V 5V 8V. The section size is: the width of the top wide belt pulley 17MM and the thickness of 10.5MM; the section size of the C triangle belt is: the top width 22MM and the thickness of 13.5MM; the section size of the D triangle belt is: the top width 21.5MM, the thickness of 19MM; the section size of the E triangle belt is the tip width 38MM, and the thickness is 25.5MM. The corresponding size (width * height):O (10*6), A (12.5*9), B (16.5*11), C (22*14), D (21.5*19), E (E). The national standard stipulates that the model of triangular belt has seven types of O, A, B, C, D, E, F, and the corresponding pulley groove angle has three 34 degrees, 36 degrees, 38 degrees. At the same time, the minimum diameter of the small belt pulley for each type of triangle belt corresponds to the angle of each kind of wheel slot, and the large pulley is not specified. The groove angle of the pulley is divided into 32 degrees, 34 degrees, 36 degrees, and 38 degrees. The specific selection should be based on the groove type and the datum diameter of the pulley; the groove angle of the pulley is related to the diameter of the pulley. The angle of the groove angle of the different types of pulley under the different diameter is as follows: the O type pulley in the diameter range of the belt is in the 50mm It is 34 degrees to 71mm; 36 degrees at 71mm to 90mm and 38 degrees at >90mm; A pulley is 34 degrees in the diameter range of 71mm to 100mm, 100mm to 125mm; >125mm is 38 degrees; B type pulley is 34 degrees in the diameter range of the pulley to 36 degrees. The belt pulley in the belt diameter range from 200mm to 250mm is 34 degrees, 250mm to 315mm is 36 degrees, >315mm is 38 degrees; D belt pulley in the belt diameter range from 355mm to 450mm is 36 degrees, >450mm at 38 degrees, E 500mm to 630mm is 36 degrees, when 38 degrees.