Vehicle Braking Control Device with Electric Motor Actuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing braking control devices for vehicles face challenges in reducing the longitudinal dimension while allowing individual control of braking liquid pressure for the front and rear wheel systems, which is necessary for maintaining vehicle stability and maximizing regenerative energy in hybrid or electric vehicles.
Innovation Solution
A braking control device that includes a master unit with a master cylinder and piston, a pressure adjustment unit using an electric pump and solenoid valves to adjust brake fluid pressure, and a regenerative coordination unit to optimize the ratio of braking forces between the front and rear wheels, allowing independent control of liquid pressures and optimizing regenerative energy generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a tandem-type slave cylinder with ball screw is used to generate brake liquid pressure, then braking force can be generated, but the longitudinal dimension becomes long
Solution Approach 1:
The patent replaces the mechanical ball screw mechanism with an electric motor that directly drives the slave piston. This substitution eliminates the need for the ball screw shaft and its associated mechanical components, significantly reducing the longitudinal dimension of the slave cylinder while maintaining the ability to generate brake liquid pressure through direct electromagnetic actuation of the piston.
Solution Approach 2:
The patent extracts and removes the ball screw mechanism from the slave cylinder assembly. By taking out the ball screw shaft and its supporting structures, the design achieves a more compact configuration where the electric motor directly actuates the slave piston, thereby reducing the overall longitudinal dimension while preserving the pressure generation function.
2Force
If reaction force chamber is provided at the end of master cylinder, then input piston movement can be controlled, but dimension in center axis direction increases
Solution Approach 1:
The patent merges the reaction force chamber with the master chamber by providing a through-hole that connects them. This integration allows the reaction force to be generated within the existing master cylinder structure without requiring an additional separate chamber at the end, thereby maintaining the center axis dimension while achieving the necessary reaction force control for input piston movement.
Solution Approach 2:
The master chamber is designed to serve multiple functions: it generates the primary braking pressure and also provides the reaction force chamber functionality through the through-hole connection. This multi-functional design eliminates the need for a separate reaction force chamber, reducing the overall center axis dimension while maintaining the ability to control input piston movement through reaction force pressure.
3Force
If tandem-type master cylinder is used, then braking liquid pressure can be generated, but longitudinal dimension is long
Solution Approach 1:
The patent applies mechanical substitution by replacing the slave cylinder's mechanical ball screw mechanism with an electric motor. This allows the master cylinder to maintain its tandem-type structure for generating braking liquid pressure while the overall longitudinal dimension is reduced through the electric actuation of the slave piston, breaking the direct mechanical linkage that previously increased the dimension.
4Stability of the object's composition
If separate control of front and rear wheel braking liquid pressure is implemented, then vehicle stability and regenerative energy can be optimized, but device complexity increases
Solution Approach 1:
The patent segments the pressure control system by providing separate slave cylinders for front and rear wheels, each with independent electric motors. This segmentation enables independent control of braking liquid pressure for each wheel, allowing optimization of vehicle stability and regenerative energy recovery. The modular electric motor actuation simplifies the control architecture compared to traditional mechanical linkages, making the segmented control more manageable.
Solution Approach 2:
The patent implements dynamic control by using electric motors that can independently adjust the position of slave pistons for front and rear wheels. This dynamic actuation allows real-time adjustment of braking liquid pressure to optimize vehicle stability during braking and maximize regenerative energy capture, with the ability to respond quickly to changing braking conditions without the inertia of mechanical systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables reduced longitudinal dimensions, improved vehicle stability, and enhanced regenerative energy capture by optimizing the braking force distribution between the front and rear wheels, ensuring effective braking performance.
Implementation Method 1
a pressure adjustment unit configured by an electric pump and solenoid valves, and that adjusts a brake liquid discharged by the electric pump to the adjusted liquid pressure by the solenoid valves
Implementation Method 2
adjusts the adjusted liquid pressure by the first solenoid valve and introduces the adjusted liquid pressure adjusted by the first solenoid valve to the rear wheel cylinder
Implementation Method 3
the ball screw shaft is driven in the advancing direction by the power of the motor, and moves the first and second slave pistons in the advancing direction against the biasing force of the coil spring, thereby generating brake liquid pressure
Implementation Method 4
the slave cylinder drives a ball screw shaft with the power of a motor serving as an electric actuator, and generates brake liquid pressure by the first and second slave pistons based on the drive of the ball screw shaft
Data Source
AI summary
A braking control device includes a master unit including a master chamber connected to a front wheel cylinder and a servo chamber that applies forward force opposing a reverse force applied to a master piston by the master chamber to the master piston, a pressure adjustment unit that adjusts brake fluid discharged by a pump to a first liquid pressure by a first solenoid valve and introduces the first liquid pressure to a rear wheel cylinder, and adjusts the first liquid pressure to decrease to a second liquid pressure by a second solenoid valve and introduces the second liquid pressure to the servo chamber; and a regenerative coordination unit having an input piston operable in conjunction with a braking operation member and an input cylinder fixed to the master cylinder, and in which a gap between the master piston and the input piston is controlled by the second liquid pressure.