Suspension Damper Cooling Bypass for Stable Oil Viscosity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional vehicle suspension dampers experience changes in damping characteristics due to thermal variations, leading to potential damage from excessive heat, which affects the viscosity of damping fluids and the integrity of rubber sealing elements.

Innovation Solution

A vehicle suspension damper design where the viscous fluid continuously circulates through a cooling chamber, transferring excess heat to the surrounding air, and a bypass assembly with a needle-type throttle and check valve controls fluid flow to manage damping and cooling, maintaining optimal fluid temperature.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the damping component operates in high temperature environments or undergoes repetitive cycles, then the damping component provides suspension function, but the oil temperature increases and viscosity decreases causing damping characteristics to change

Engineering Contradiction:
Improvedamping characteristics consistencyVSAvoidoil temperature
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The patent converts the harmful heat generated by repetitive damping cycles into a beneficial cooling process by directing the hot damping oil through a cooling chamber where excess heat is transferred to surrounding air, transforming the thermal problem into a controlled heat dissipation mechanism that maintains consistent damping characteristics

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent introduces a cooling chamber as an intermediary component between the damping cylinder and the environment. This cooling chamber acts as a heat exchange mediator, transferring excess thermal energy from the damping oil to the surrounding air through controlled circulation, thereby protecting the damping system from thermal degradation

Inventive Principle:
Principle #24Intermediary (Mediator)

2Duration of action of moving object

If the oil temperature increases, then the damping component operates continuously, but the viscosity of the oil decreases allowing oil to flow more easily through the vented damping piston

Engineering Contradiction:
Improvecontinuous operation capabilityVSAvoiddamping control precision
Core Design Contradiction:
Duration of action of moving objectVSEase of operation

Solution Approach 1:

The patent implements a thermal feedback mechanism where the temperature of the damping oil is continuously monitored and this information is used to regulate flow through the cooling chamber. When oil temperature rises and viscosity decreases, the system automatically increases cooling effectiveness to restore optimal viscosity, creating a self-regulating loop that maintains damping control precision during continuous operation

Inventive Principle:
Principle #23Feedback

3Adaptability or versatility

If the temperature fluctuation is high, then the damping component adapts to different environments, but the rubber sealing elements degrade causing permanent damage

Engineering Contradiction:
Improveenvironmental adaptabilityVSAvoidsealing element integrity
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent applies preliminary cooling action by continuously circulating damping oil through the cooling chamber before the oil reaches temperatures that would cause rubber sealing element degradation. This proactive heat management prevents thermal damage to sealing elements while allowing the damping component to operate in diverse environmental conditions, maintaining both environmental adaptability and sealing integrity

Inventive Principle:
Principle #10Preliminary action

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 regulates fluid temperature, preventing damage from excessive heat and maintaining consistent damping performance across varying operating conditions.

Implementation Method 1

the viscous fluid in the suspension damper is continuously circulating through the cooling chamber during the stroking of the piston, thereby transferring excess heat to the air surrounding the cooling chamber

Methodology Applied
Scientific EffectHeat transfer: Convection

Data Source

PatentEP2495472B1Cooler for a suspension damper
Publication Date: 2024.05.01 FOX FACTORY INC
  • EP2495472B1 patent drawingFigure 1
  • EP2495472B1 patent drawingFigure 2
  • EP2495472B1 patent drawingFigure 3

AI summary

A method and apparatus are disclosed for cooling damping fluid in a vehicle suspension damper unit. A damping unit (100) includes a piston (105) mounted in a fluid cylinder (102). A bypass fluid (256) circuit having an integrated cooling assembly (200) disposed therein is fluidly coupled to the fluid cylinder at axial locations that, at least at one point in the piston stroke, are located on opposite sides of the piston (105). The cooling assembly (200) may include a cylinder (202) having cooling fins (204) thermally coupled to an exterior surface of the cylinder (202) and made of a thermally conductive material. The bypass channel (256) may include a check valve (280) that permits fluid flow in only one direction through the bypass channel (256). The check valve (280) may be remotely operated, either manually or automatically by an electronic controller. A vehicle suspension system may implement one or more damper units (100) throughout the vehicle, controlled separately or collectively, automatically or manually.