To study the structure of telecentric beam path for zoom lens system, the axial displacement equation for the stop was deduced, which keep the system telecentric in all zoom position.
In view of the characteristic that there is an axial hydro - thrust in Turgo turbine, a double stop thrust construction of double inclined planes back by back in the bearing can be used.
鉴于斜击式水轮机具有轴向水推力的特点，在这套卧式液体静压轴承中采用了双斜面背靠背的双止推结构。
3
Erosion of the blade by the solid particle of the smoke and gas is the major problem of axial flow fan, which may make axial flow fan reduce power and even stop working.