The structural decomposition of the planar projectile and the definition of the functional structure can be seen. Although the shape of the planar microspring is various, from the perspective of the planar rigid frame structure, the MEMS planar micro-elastic is composed of the elastic beam in two-dimensional space. They are connected to each other at a certain angle. Therefore, the planar microspring can be structurally decomposed to obtain a functional structure that plays a major role in the deformation of the spring. The planar miniature spring functional structure is generally a planar miniature spring. The spring composed of the functional structure can obtain the spring that adapts to the different requirements of the MEMs in the same space by changing the basic parameters of the functional structure, which is also the primary problem to be solved in designing the planar miniature spring for MEMS. Through the above analysis, the functional structure of the planar microspring is defined as follows: the elastic beams are connected to each other at a certain angle in a two-dimensional space, which is a basic structure that constitutes a planar microspring, and plays a main role in the deformation of the spring. It is a functional structure of a planar miniature spring. The relationship between the shape parameters of the functional structure and the stiffness coefficient In the analysis, the elastic modulus of the agreed material is E, the moment of inertia is I, and the external force of the structure is F. The functional structure of the 23 kinds of plane emblems of the functional structure circle of the suspended potassium beam is The cantilever beam shown in (c) is a functional structure that can constitute the simplest structure of a planar microspring, the S-type, while the other two functional structures can be used to form other shapes under the same structural width, when the structural shape parameters . For the cantilever beam structure, the width of the structure, that is, the length l of the cantilever beam, does not change, so the stiffness coefficient does not change. According to the symmetry of the structure, only the right half is analyzed, as shown in (b). As can be seen from the figure, the spring is composed of two elastic cantilever beams parallel to the X-axis and one elastic beam parallel to the Y-axis. The S-type plane bombs are praised by the functional structure, the suspended sill. Using the energy method in material mechanics and structural mechanics, the displacement of the end point of the S-shaped plane is shown in the Y direction and the stiffness coefficient under the action of the force F, for the application of planar miniature springs based on these three functional structures. In MEMS, when the system space width is constant and a spring with a large stiffness coefficient is required, an S-shaped planar emblem-type projectile composed of cantilever beams can be used; when the system space width is constant and a spring with a small stiffness coefficient is required, A planar microspring composed of a rectangular raised structure or a triangular raised structure may be employed, and by changing, and a, a spring more suitable for the system stiffness coefficient is selected. In the following analysis, the design method of the planar emblem I of the functional structure is assumed to be that the line width of the spring structure is h, the gap of the projectile structure is d, and the other required dimensions are given by the figure. It is known from the previous analysis that the structure of the MEMS spring is planar, so the design is from the simplest one of the planar structure, from the material mechanics and structural dynamics, the S-type spring is the functional structure - the cantilever beam The simplest kind of planar miniature spring is constructed as shown. Under the condition that the external force F and the elastic modulus E of the material are constant, the stiffness coefficient of the S-shaped planar spring is determined by the length l of the cantilever beam, the gap d of the elastic structure and the line width of the spring; These dimensions reflect the overall space size axb of the MEMS placement spring. If the stiffness factor of the designed S-type planar spring does not meet the requirements of MEMS within a given spatial dimension axb, a spring with a smaller stiffness coefficient is broadcast, without changing the functional structure of the spring (ie, the structural shape of the spring) Constant), need to consider two aspects: 1 increase the length of the S-spring parallel to the X-axis elastic cantilever beam and the f-segment elastic beam parallel to the Y-axis, but this will inevitably lead to an increase in the size of the space, which is limited space MEMS is not feasible; o reduces the thickness or line width of the planar spring structure, but this will be limited by the MEMS processing technology, and the strength of the camouflage is also greatly reduced, so that the reliability in practical applications decline. For the two functional structures of cantilever beam and rectangular protrusion, when the structure width is the same, the stiffness coefficient of the cantilever beam is larger than the stiffness coefficient of the rectangular protrusion; therefore, for this reason, in order to obtain a smaller stiffness coefficient in a given space The spring replaces the cantilever beam portion of the S-shaped magazine with two functional structures as shown, thereby realizing a planar projectile with a small design stiffness coefficient in a specific space. Conclusion From the perspective of material mechanics and structural mechanics, MEMs can be seen as planar rigid frame structures with planar miniature springs; by decomposing the rigid frame structure, functional structures that have a major influence on the spring stiffness coefficient can be obtained; In the space, the preliminary design of the MEMS spring can be realized by the replacement of the functional structure and the transformation of the main dimensions of the functional structure to meet the requirements of the MEMS. Carbon Steel Fasteners,Carbon Steel Screws,Mild Steel Screw,Carbon Steel Anchor Bolt Taizhou TS HARDWARE Co., Ltd , https://www.shuwengroup.com
Preset according to the trait structure of the MEMS spring