Master Cylinder Stroke Velocity Ratio Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing master cylinder apparatuses in hydraulic brake systems face challenges in initial response delay and stroke velocity ratio management, particularly during abnormal electrical system conditions, due to limitations in stroke velocity ratio modification and communication condition control.
Innovation Solution
The introduction of a stroke velocity ratio modification device and a communication condition control device that adjusts the stroke velocity ratio in multiple stages, including an initial stage and normal use region, by modifying the effective pressure receiving surface areas and controlling communication conditions between the inter-piston chamber, opposing chamber, and reservoir, ensuring optimal brake operation and response even under abnormal conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the stroke velocity ratio is increased in the initial stage of brake operation, then the initial response delay is suppressed, but the stroke velocity ratio becomes excessively large which may cause instability
Solution Approach 1:
The patent applies dynamics by making the stroke velocity ratio variable rather than fixed. The ratio is dynamically adjusted based on the brake operation stage: in the initial stage, the ratio is increased to reduce response delay, while in the normal use region, the ratio is reduced to ensure stability. This is achieved through the communication condition control device that switches between different communication conditions (first condition with higher ratio, second condition with lower ratio) based on real-time operational needs.
2Ease of operation
If the stroke velocity ratio is reduced in the normal use region, then the brake operation feel is improved, but the initial response may be delayed
Solution Approach 1:
The system dynamically adjusts the stroke velocity ratio based on the operational phase. During normal use, the ratio is reduced to provide better brake operation feel and control. When initial brake operation is detected, the system switches to a higher ratio to ensure rapid response. This dynamic adaptation resolves the contradiction by optimizing the ratio for the current operational context rather than using a fixed value.
3Productivity
If communication conditions are switched between first and second conditions, then the stroke velocity ratio is optimized for different stages, but the device complexity increases
Solution Approach 1:
The communication condition control device performs multiple functions: it monitors the brake operation stage, determines the appropriate communication condition, switches between different communication conditions, and maintains optimal stroke velocity ratio. By consolidating these functions into a single control device, the patent reduces overall system complexity while achieving improved brake response efficiency across different operational stages.
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
This solution effectively reduces the initial response delay and improves brake operation feel by dynamically adjusting the stroke velocity ratio, ensuring reliable performance even when an abnormality occurs in the electrical system, by integrating a solenoid valve control unit and a communication condition control mechanism.
Implementation Method 1
a pressure piston that is provided in front of the input piston and is configured to move relative to the input piston; and a stroke velocity ratio modification device that is configured to modify a stroke velocity ratio
Implementation Method 2
fluid pressure from a rearward back surface chamber
Data Source
AI summary
A master cylinder apparatus includes: an input piston that can be moved forward by operating a brake operating member; a pressure piston that is provided in front of the input piston to be capable of moving relative to the input piston; and a stroke velocity ratio modification device that is capable of modifying a stroke velocity ratio, which is a ratio between a stroke velocity of the pressure piston and a stroke velocity of the input piston, in at least two stages while the input piston moves from a rear end portion position to a front end portion position, and that sets the stroke velocity ratio at 1 when an abnormality occurs—in the master cylinder apparatus.