Miniature bearing load and speed

Most of the power transmission for use with bearing mechanical parts are involute gear. The gear driving force between the parallel axis. As the mechanical design teaching material ( For example, potts and Shoup Juvinall and Marshek2, Hamrock and others, and others) Suggests, load normally with pressure Angle along the pitch circle of gear contact by the tangent to the tooth surface of gear teeth. Load P P can be decomposed into tangential load, radial load and P. Figure 4 said by straight gear in the gear pitch circle radius, the transfer of load. Tangential load P can be determined by the power relationship between NUPI H = 4. 13) 60 type determined under radial load available: P, = P tand. 4. 14) Type ( 4. 13) Type ( 4. 14) To transfer power between parallel axis of herringbone gear is also applicable. Herringbone gear as shown in figure 4. 5. Figure 4. 4 straight gear load transfer of load transfer of the planetary gear as shown in figure 4. 6. As you can see effect the total radial load on axle is 2 p. In addition, the radial load is balanced, that is, they can offset each other. In volume 2, chapter 1, the book shows the radial load bearing outer ring bending, and impact of rolling load distribution. 4. 2. 3 take - Pulley wheel and chain transmission load structure usually produce radial load, as shown in figure 4. 7. Can be seen from the diagram, the load acting on the shaft tension load force function. Due to the expansion of the belt in the transmitted power and change, pre-load is generally larger than that of theoretical calculation value of the belt. Radial load on the shaft about for P = P (D 4. 15) Type in the P for theoretical belt wheel load. If the belt cross section is very big, is P = A + ( 4. 16) Type A is the area of the cross section. , 2, and the value in table 4. 1 is given. In table 4. 1, when belt speed is low, in figure 4. 7 with a structure of the larger ∫ value is appropriate; When the center distance of minor or poor operation condition, should choose larger values.