Abstract: Abstract: In the recent years, with the normal circular gear revealing deficiencies, the studies on the new type of gear pair have attracted more and more attention. Taking the non-circular gear as an example, the pitch curve of non-circular gear is no longer a circle, so it can realize variable transmission ratio, and it can achieve continuous reciprocating movement after combining with link mechanism. This paper aimed to study the movement characteristics of the new type of gear pair. The pitch curve equation of the surface gear was obtained based on the normal circular gear. From the equation, it could be found that the equation included four parameters: the angular velocity ω, the number of surface gear n, the length of connecting- rod la and lb. And the related curves were displayed by MATLAB (Matrix laboratory). Based on the analysis of the surface gear, the surface gear pair could make the continuous transmission in a rotating cycle. What's more, its angular velocity could implement the periodic changes. Combing with the surface gear, we obtained the composited surface gear -crank-link mechanism; it combined the advantages of the gear pair and the crank-link mechanism, which could realize the expected trajectory and speed at the same time. Based on the principle of space gear and differential geometry and other related theories, the moving and static coordinate system of the composited mechanism were established, and then the movement equations of composited mechanism could be deduced. We could also get the displacement, velocity, acceleration and their variation tendencies by MATLAB, which provided the theoretical basis for the control of this mechanism. Based on the properties of the composited mechanism, a type of forage baling machine for packing agencies was designed. In addition, the simulation machining and characteristic analysis system of surface gear pair was developed using application programming interface (API) in Solid Works. The system was used to analyze the selection method and principle of correlation parameters in surface gear pair design, and the solid simulation model of the surface gear pair and the briquetting machine model were established. And the movement simulation was done by importing the mechanism into the ADAMS (Automatic Dynamic Analysis of Mechanical Systems). The composited mechanism was produced by CNC (Computerized Numerical Control) machine, and the related experiment was finished in 2015. In the experiment, the surface gear was as the input part (constant rotating speed) and the slider as the output part (the displacement). During the experiment, the slider can realize the reciprocating movement. The displacement and velocity of the slider were recorded every 4 s, and the recording time was 60 s to reduce the conflict from assembly error. Compared with the theoretical data, the error of the gear pair, displacement, velocity and acceleration were 2.8%, 0%, 3.4% and 3.6%, respectively. These data confirm the correctness of the theoretical analysis, which has a guiding significance for subsequent similar research.