Key Technologies Research Of Integrated Electric Park Brake Caliper

As an important part of the automotive safety system,car brakes had been developed with the innovations of automotive technology.The innovations result in a technology named Electric Park Brake(EPB)which was developed in recent years.The main direction of future development of the technology is integrated Electric Park Brake(iEPB)system.This iEPB is different from traditional handbrake with the combination of electronic and mechanical component.It adds a motor as an actuator to replace the handbrake lever with a button.The subject of this article is about the key technologies of integrated electric park brake calipers.The study is based on an existing caliper product,to reverse-engineer it.In addition to the study on caliper structure design,it also involves with motor,speed reducer,rubber seals and calipers manufacturing process.In the process of the research,I used the optical scanner to reverse the caliper cylinder and measure its size by scanning.Creating the 3D model caliper parts with Geomagic and UG software.And then design tolerances and dimension chains.Matching the speed,inertia and the power of three existing motors according to the working condition so as to select the most suitable motor as the driving part for parking brake.Designing the basic parameter and modification of two stages of epicyclic gears restricted by the installation condition.In the design of the key parts of the caliper,the retraction has always been the critical point of braking performance.In this paper,I carried out the tensile test of the piston seal rubber,and used the Abaqus to fit the curve.Then the best fit model of super elastic material was selected to simulate the piston retraction to verify if it meets the design requirements.In the strength analysis of the caliper cylinder,Hypermesh and Abaqus were used to meshing and statics analysis,and the fatigue of the caliper was calculated based on the analysis results.In the reliability analysis of the gear reducer,the mechanical properties of the powdery material was calculated through the basic characteristics of the powder in cooperation with semi-empirical and empirical formula.And Hypermesh and Abaqus was used for the dynamic intensity and mode simulation of the gears.This paper also studied the processing technology in order to ensure the mass production of the caliper cylinder.With the existing CNC machining center,machining process was arranged for caliper cylinder.And special fixture with position project for caliper cylinder was design for the CNC machining center.