Master Cylinder Balancing Valve Shutter Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing master cylinder assemblies for agricultural vehicles are bulky due to mechanically connected pistons and valves, leading to degraded seal performance and potential damage from high fluid pressures, especially at elevated temperatures.
Innovation Solution
A master cylinder assembly with balancing valves mechanically unconstrained from the piston, featuring a parallel configuration to reduce size and improve sealing, using metal-to-metal seals and a compact design to prevent fluid accumulation and pressure increases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the piston and valve shutter are mechanically connected in series, then the balancing function is achieved, but the master cylinder assembly becomes bulky in longitudinal direction
Solution Approach 1:
The patent divides the balancing function into two independent parts: the piston remains responsible for pressure generation while the valve shutter becomes an autonomous component activated by fluid pressure from the chamber. This segmentation eliminates the need for mechanical series connection, allowing compact longitudinal arrangement while maintaining balancing functionality.
Solution Approach 2:
The patent replaces the mechanical series connection with a hydraulic activation mechanism. The valve shutter is activated by fluid pressure from the chamber rather than direct mechanical coupling with the piston. This allows the valve to be positioned closer to the piston, reducing the longitudinal size while maintaining the balancing function through fluid-mediated actuation.
2Ease of manufacture
If sealing gaskets are used for the shutter seal, then the assembly is easier to manufacture, but the seal performance degrades during operation due to friction and wear
Solution Approach 1:
The patent replaces the mechanical sliding contact system with a metal-to-metal sealing system. Instead of using elastomeric gaskets that slide against bore surfaces, the shutter employs a metal sealing surface that contacts a corresponding metal surface, eliminating friction and wear associated with gasket materials while maintaining sealing effectiveness.
Solution Approach 2:
The patent employs different material properties for the shutter and bore surfaces to achieve optimal sealing. By using metal materials with appropriate surface finishes and hardness characteristics, the system achieves durable sealing without the degradation issues of elastomeric gaskets, combining the advantages of manufacturability with long-term reliability.
3Reliability
If the balancing duct is closed at its ends by balancing valves, then pressure balancing is achieved, but fluid pressure increases considerably at high operating temperatures
Solution Approach 1:
The patent extracts the fluid accumulation problem by providing a dedicated drainage path that allows fluid to escape from the balancing duct. This prevents pressure buildup during temperature increases while maintaining the pressure balancing function when needed, effectively removing the harmful pressure accumulation effect.
Solution Approach 2:
The patent introduces a drainage orifice as an intermediary element that mediates between the closed balancing duct and the external environment. This small opening allows controlled fluid release to prevent pressure buildup while not interfering with the primary pressure balancing function when the valves are closed.
4Reliability
If sealing gaskets are used in the balancing duct, then sealing is initially effective, but the gaskets risk being damaged by high fluid pressure when brakes are not used
Solution Approach 1:
The patent replaces the elastomeric gasket sealing system with a metal-to-metal sealing system in the balancing duct. This eliminates the risk of gasket damage from high fluid pressure while maintaining sealing effectiveness, as metal surfaces can withstand high pressures without the deformation and failure modes of elastomeric materials.
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 results in a more compact and reliable braking system with improved sealing performance and reduced risk of damage from high pressures, ensuring effective balanced braking even under high-temperature conditions.
Implementation Method 1
a shutter (62) slidable in a cavity or housing (64) parallel to chamber (16) and movable in a sliding direction parallel to and oppositely oriented with respect to operating direction of piston (15), against the action of a resilient return member (66), wherein the shutter (62) is operable for opening in a manner fluidically controlled by a control pressure taken by the fluid contained in chamber (16)
Implementation Method 2
movable in a sliding direction parallel to and oppositely oriented with respect to operating direction of piston (15), against the action of a resilient return member (66)
Data Source
AI summary
The invention concerns a master cylinder assembly (10, 110) for balancing the braking of a couple of wheels (LBW, RBW) of a vehicle. Each master cylinder (12) has a hollow body (14), a piston (15) and a chamber (16) suitable for containing a fluid having a primary control pressure depending on a driving force applied on the piston (15) and intended to be transmitted to a utilizing device (LBB, RBB). The assembly further includes a balancing duct (58) into which the chambers (16) come out, and a plurality of normally closed balancing valves (60). Each balancing valve (60) is located between the balancing duct (58) and a respective chamber (16) and has a shutter (62) which is mechanically unconstrained to the primary piston (15) defining the primary chamber (16) to which said primary balancing valve (60) is associated, and which is operable for opening in a manner fluid-controlled by the primary control pressure taken by the fluid contained in the primary chamber (16) to which said balancing valve (60) is associated.