The structure and working principle of a new translational piston compressor was introduced in this paper. Its piston works in a way of translational motion, hence reduces the piston’s relative velocity to cylinder and cap, as well as friction and wear. In order to avoid vane detaching from piston, simulations were carried out regarding the pre-tightening spring and an optimal preload of the spring was obtained. By analyzed and compared to conventional rolling piston compressor in term of contact force between vane and piston, it was pointed out that the new compressor possessed advantage of kinetic characteristic and is more suitable for the situation of high rotary speed.

By using virtual prototype technology, a model of Embedded Vane Rotary Compressor has been established for motion simulation. Based on theoretical analysis and simulation, the motion characteristic, forces and connection constraints was studied and analyzed. The results are helpful for improving the design and performance of the compressor.

A new type of variable structure motorcycle helmet is proposed in this paper, in which that the helmet’s chin-guard can be transformed between the full-helmet status and the half-helmet status as needed. The helmet creatively adopts double movement nails and double track grooves to constraint the chin-guard movement according to the predetermined trajectory, and thus smoothly accomplishing the chin-guard’s lifting, climbing, passing zenith, falling and closing in the helmet shell. The paper introduces the chin-guard’s trajectory planning principles, realizing methods and designing steps, and then gives a design case for the constraint slot tracks in detail. The results show that the new type helmet can reliably realize helmet structure conversion between full-helmet and half-helmet and fully meets the design requirements.

A new type of stationary blade rotary compressor is developed to overcome the rolling piston compressor’s weaknesses such as severe leaking loss and friction waste. The new compressor has unique sealing structures and friction-reducing techniques, featuring in that the compressor adopts a stationary blade whose out-end is hermetically fastened to the cylinder’s inner wall and the blade’s two side-ends are hermetically fastened to the end-covers which respectively set in both ends of the cylinder. Due to that the cylinder, the blade and the end-covers all are closely fitted to each other, the leakage and friction occurred from these parts are completely eliminated. This paper introduces the compressor’s working principle and structure characteristics, deduces the calculation formulas for displacement volume, chamber pressure and thermodynamic properties, and discusses the design principles of compressor structure parameters and what effects these parameters have on leakage and friction. The research result shows that the stationary blade compressor, in comparison with the conventional rolling piston compressor, has displayed some unique advantages in seal property, friction reduction, manufacturing and assembling techniques.

The structure and working principle of a new translational piston rotary compressor was introduced and made theoretical analysis in this paper. It was pointed out that the translational piston rotary compressor had not only fine practical, which with less friction loss and leak loss than the traditionally rotary compressor, but also the advantage of simply structure and technics and low manufacturing cost. The rotary compressor was practical and promising.