Common spring stiffness
Elastic modulus is one of the most important and characteristic mechanical properties of elastic materials. It is the characterization of the difficulty of the deformation of the object. It is expressed in E. It is defined as the ratio of the stress to the corresponding strain when an ideal material has small deformation. E is expressed in terms of the force per unit area. The unit is cattle / rice ^2. The properties of the modulus depend on the properties of the deformation. The modulus of shear deformation is called shear modulus, which is expressed by G. The modulus of compression deformation is called the modulus of compression, expressed by K. The reciprocal of the modulus is called the flexibility, which is expressed in J.
The yield limit B and strength limit S, which are obtained in the tensile test, reflect the bearing capacity of the material to force, and the elongation rate delta or cross section shrinkage rate reflects the capacity of the material shrinkage deformation. In order to indicate the difficulty of resistance to deformation in the elastic range, the elastic modulus E of the material is in the actual engineering structure. The meaning is usually reflected by the stiffness of the part, which is because once the part is designed and fixed according to the stress, the stiffness is judged by the amount of deformation produced by the load during the service process in the elastic deformation range.
Where lambda - stress induced strain
F--- stress
The average value of the inner and outer diameter of the D--- spring coil
Shear modulus of elasticity of G---
D--- spring bar diameter
The number of n--- effective cycles
Generally, the load caused by the unit strain is used as the stiffness of the part, and the unit of the spring stiffness is N/mm, so it can be simplified as: stiffness = (G*d4) / (8*n*D3), and the formula for calculating the stiffness of the series spring is 1/k=1/ (K1) +1/ (K2), in which K is a stiffness.
In order to improve the stiffness E of parts, that is to reduce the elastic deformation of the parts, the material with high modulus of elasticity and the proper cross section of the bearing can be appropriately increased. The importance of stiffness is that it determines the stability of the parts during service and is particularly important for slender rod and thin-walled components. Therefore, for the theoretical analysis and design calculation of components, the elastic modulus E is an important mechanical performance index often used.
The formula for calculating the stiffness of cylindrical springs can also be simplified as follows:
F '=GD/8C4n;
G - shear modulus of elasticity;
D - the middle diameter of the spring;
C - winding ratio, C=D/d;
D - the diameter of the spring wire
The spring winding ratio of the ellipse is C= (D/d) * (b/a) 2,
among
D -- the middle diameter of the long axis of the ellipse
A - the middle radius of the long axis of the ellipse
B -- the radius in the short axis of the elliptical circle
D - the diameter of the spring wire
The spring expansion length of the section is ellipse L=n1D PI zeta 2.
N1 - the number of the total spring rings
D -- the middle diameter of the long axis of the ellipse
Zeta 2 - length correction coefficient is selected according to b/a in the following table:
Two. Spring contact finger
The coil spring is a circular spring. Its Rao coil is elliptical and tilted. When compressed, each coil will be deformed individually. No matter which part of the coil is deformed, the whole spring will react to achieve the same load at each point.
For the connector, the end of the spring will be welded to form a complete ring. For the specific insertion or pull out of each standard coil size, the spring can be put into the groove in the design of the socket and plug. When the groove is inserted into the groove, the spring's coil spring is acting on the continuous spring stress. In this way, the load and groove design of the coil will produce a continuous spring stress, so that a corresponding pulling force is needed to break the 2 parts. On the buckle of the mini connector, the diameter of the coil spring has 2 key functions and can be used. Reduce the number of components in the system.
The coil spring provides dual functions, which can be used as a mechanical joint, and can also maintain the circuit between the external thread joint and the internal thread joint, thus reducing the RF interference to the minimum. The design of the electronic interconnect is more complex. The simple and compact design provides a new test for the interconnection design of military, industrial and commercial applications. The speed is increasing, and the size of the electronic component is decreasing. Therefore, the connector needs to process more signals at a higher speed in a smaller space, or more in the more compact space, and the smaller the size of the connector, its unique elastic deformation curve, the wide scope of work - the spring license compression is up to 35%. Relatively stable elasticity reduces temperature difference, tolerances and other deviations caused by wear. Each coil can play a separate role.
