Design principles in the development process of the spring industry:
A spring is a mechanical part that uses elasticity to work. It is generally made of spring steel. It is used to control the movement of the mechanical part, ease the impact or vibration, store energy, and measure the size of the force. It is widely used in machines and meters. According to the shape, there are mainly spiral springs, disc springs, scroll springs, leaf springs, etc.
Railway vehicles can be roughly divided into car bodies, bogies, connecting buffer devices and other parts. Bogies are the running parts of railway vehicles. Its function is to bear the weight of the upper part of the car body, transmit traction and braking force, and alleviate the impact of the line on the vehicle. The bogie generally includes wheel-set axle box device, elastic suspension device, frame and side frame, basic braking device, car body support device and other parts.
At present, the main bogie of China’s railway freight car is Zhuan 8A bogie, including : Bearing, wheel set, side frame, wedge block, bolster, pillow spring, chute type basic brake device, side bearing and lower center plate and other main components. Spring factory
The design problem of bogies is a more complicated problem in the design of railway freight cars. The safety and stability of vehicle operation mainly depend on whether the design of the bogie is reasonable. In the design of the bogie, the spring damper is the key component, and the spring damper There are more than 20 main parameters, more than a dozen static constraints, the vibration of the vehicle system (including vertical, lateral, roll, nodding, etc.), the snake movement of the wheel set (different at low speed and high speed), and the curve of the train passing The characteristics (anti-overturning and anti-derailment performance through the curve) and other dynamic performance are directly related to the structural parameters of the spring damper.
The design of the bogie generally needs to go through three steps: design parameters, finite element analysis and dynamic performance check. The current design activities follow the form of “design, analysis, change”, that is, perform finite element analysis or dynamic performance check. Can not meet the requirements, and then return to the design department for modification.
Due to the many parameters involved, the coupling relationship between the parameters is also more complicated, the design of the bogie structural parameters often takes more time. Especially the structural parameters are for the dynamic performance of the vehicle The influence of the design can only be judged by the experience of the designer.When the model is more complicated, it is easy to cause the designer to make a mistake in the judgment, and the engineering change will bring about the prolongation of the product development cycle and the decline of the quality level.
Therefore, it is necessary to provide designers with a tool to enable them to intuitively understand the influence of parameter adjustment on dynamic performance when performing structural parameter design calculations. The following is a simple example to illustrate how to use the design principle to guide the parameters. adjust.
The spring shock absorber in the bogie is treated as a key component, and its behavior simulation and principle explanation are carried out, but the designer analyzes the vibration performance of the vehicle after completing the parameter design of the spring and shock absorber. In the simplified model, (a) only considers the vertical free vibration with nonlinear damping, and (b) is a schematic diagram of the spring damper.
There are more than 20 parameters of the spring damper, including the diameter of the spring bar, the number of spring coils, Spring stiffness, friction surface angle, friction surface coefficient, etc., are appropriately simplified according to simulation needs.