In the past, when selecting a reducer for purpose braking, the requirements for the control accuracy of the reducer were often neglected. In this regard, many countries have taken many detours.In order to control the brake reducer for many purposes, it is uneconomical to manually disperse all the control, so it is necessary to use semi-automatic or automatic control.
At the same time, in order to improve the link rate, the vehicle must have an accurate speed from the exit of the reducer.Of course, this should be controlled from the entire closed-loop control system of the reducer, but the final accuracy largely depends on the performance of the actuator-reducer.
The influence of the performance of the worm gear reducer on the control accuracy is introduced as follows:
XNUMX. Calculation formula of speed deviation V of reducer outlet
During the braking process, due to the inertia of the reducer and the control system (that is, the mitigation time of the reducer and the delay time of the control system), there will always be a certain deviation between the required exit speed and the actual exit speed. In order to make the actual outlet velocity as close as possible to the required outlet velocity, the reducer must have an early relief time, that is, the relief starts when it is higher than the required outlet velocity.
This means that speed changes due to the inertia of the reducer and control system must be compensated for.In the reducer control circuit, methods such as fixed compensation or compensation according to deceleration are commonly used.At present, a more reasonable method is to compensate according to the reducer.
In the automated system, according to the resistance of the vehicle, the idle length of the track is calculated, so it is affected by the accuracy of the resistance measurement, the accuracy of the length measurement and the authenticity of the calculation equation of motion. On the other hand, even if the accurate exit speed is calculated , but it is also affected by the deceleration of the truck during the braking process. The delay mitigation time of the control system is also affected.
In the semi-automatic system, the exit speed is manually given, and its error refers to the deviation between the actual exit speed and the given exit speed, which is determined by the deceleration of the truck during the braking process. The delay mitigation time of the control system decided.
In the semi-automatic system, the error is required to be more than 95% and no more than 1KM/H, and in the automatic system, higher output speed control accuracy is required.
XNUMX. The influence of time deviation on exit speed deviation
Reducing the relief time and reducing the deviation of the worm gear reducer is one of the primary conditions for the purpose braking reducer.
XNUMX. Influence of deceleration deviation on exit speed deviation
In addition to the economic requirements for the target braking reducer, it is more important to put forward higher requirements than the interval braking reducer in terms of performance.This is also one of the important factors why countries have invested a lot of manpower and material resources in research in the past ten years.