英译汉The springs used The springs used in this research are flexible cantilevers as depicted in figure 6. These springs and the piston are one monolithic structure in order to avoid the assembly of small springs. The spring bed is made in stainless steel using wire-µEDM. This production technique allows very high aspect ratios: the springs shown in figure 6 are 50 µm wide and 3000 µm long. A piston with diameter 1 mm and length 2.5 mm and a piston rod with diameter 500 µm have been assembled with each of these three techniques. The angle error α (see figure 4) equals 0.5 º in case of cylindrical assembly, 0.41º in case of the cones and 0.33º in case of spring beds. The main disadvantage of using spring beds is that they are difficult to produce.