According to the basic structure and transmission principles of push rod rack drive,the paper analysed the principle of creating and meshing of rack profile when revolving-stock was partial- ity disc.

The basic structure and transmission principle of push rod rack drive are introduced and the force states of push rod in different cases are analyzed in detail,Considering the effect of inertia force,an accurate formula of meshing efficiency is derived according to the definition of meshing efficiency;and it provides a theoretical basis for its capability testing and further research.

The paper introduces the basic structure and transmission principle of push rod rack drive and gives the formula and recommendatory value of the main parameters of the push rod rack drive,which provides a theoretical basis for its design and manufacture.

In the design of the cavity mould, the diameter of the ejector pin is usually determined based on one's experience or according to analogism.

s:Through theoretical analysis and scanning electron microscope verification,the push rod of two stage pusher centrifuges fractures in productive are analysis and put forward an improvement plan.

In this paper,the push rod in HR500 N Centrifuges fractures in productive are analysis and put forward an improve measure.

The gear shifting was realized by moving push-rods and two wedge sliders.