Flow Control Thermostat Valve Gradual Coolant Introduction

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Mechanical thermostats in internal combustion engines experience uncontrolled coolant flow due to vibration and flexible joints, leading to sudden temperature changes that can cause engine damage and inefficiency, particularly in colder climates.

Innovation Solution

A thermostat with a tube-style valve member and a flow control element that controls the initial coolant flow, ensuring a gradual introduction of coolant into the engine by shaping the flow control surface to manage the flow rate and incorporating a fail-safe feature to maintain an open position during overheating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a mechanical thermostat with flexible joints is used to allow valve movement, then the thermostat can operate reliably through vibration resistance, but uncontrolled coolant flow and temperature fluctuations occur due to valve chatter

Engineering Contradiction:

Improvethermostat operation reliabilityVSAvoidcoolant flow control precision

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

A flow control element is introduced as an intermediary component between the valve member and coolant flow path. This element mediates the coolant flow, providing a guiding surface that directs flow while the valve member provides thermal actuation. The intermediary element prevents direct interaction between the vibrating valve and uncontrolled flow, resolving the contradiction between reliable operation and flow control precision.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Temperature

If the thermostat valve opens quickly to allow coolant circulation, then the engine can be cooled effectively, but sudden temperature drops occur causing thermal shock to engine components

Engineering Contradiction:

Improveengine cooling effectivenessVSAvoidthermal shock to engine components

Core Design Contradiction:

TemperatureVSObject-affected harmful factors

Solution Approach 1:

The flow control element creates a gradual, controlled opening sequence rather than sudden full opening. As the valve member lifts, the flow control surface guides coolant flow in a controlled manner, creating a periodic progression from restricted to full flow. This periodic action prevents thermal shock while maintaining effective cooling.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The flow control element acts as a cushioning mechanism that prepares for the incoming coolant flow by guiding it through a controlled path. Before the full coolant volume reaches the engine, the flow control surface gradually introduces coolant, cushioning the thermal transition and preventing sudden temperature drops that cause thermal shock.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Productivity

If the valve is held closed to prevent coolant flow, then the engine heats up quickly to optimal temperature, but overheating risk increases if the thermostat fails

Engineering Contradiction:

Improveengine warm-up speedVSAvoidoverheating protection

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The flow control element is pre-configured with a guiding surface that ensures gradual flow introduction. This preliminary configuration means that even if the valve fails in the closed position, the flow control geometry itself provides a fail-safe mechanism that allows controlled coolant passage, preventing complete overheating while maintaining normal warm-up performance.

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

The solution prevents sudden coolant rushes, reducing thermal shock and pollution, allowing the engine to reach optimal temperature faster and maintain efficiency, while ensuring the thermostat fails safely open to prevent engine damage.

Implementation Method 1

The wax is solid at low temperatures, but as the engine heats up the wax melts and expands

Methodology Applied

Scientific EffectMelting: Melting

Implementation Method 2

the wax melts and expands. As the wax expands, it pushes an actuator rod outwardly from the chamber

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 3

shaping the flow control surface to manage the flow rate

Methodology Applied

Scientific EffectFluid flow control:

Implementation Method 4

The solution prevents sudden coolant rushes, reducing thermal shock

Methodology Applied

Scientific EffectThermal shock reduction: Thermal Shock

Data Source

PatentUS7490581B2Flow control thermostat for internal combustion engines and method of use of same

Publication Date: 2009.02.17 FISHMAN THERMO TECH

AI summary

A thermostat for an internal combustion engine. The thermostat includes a tube type bypass valve member; a spring to keep said valve member in a closed position and a temperature sensitive actuator to move said valve member to an open position. A flow control element is provided to control a flow of fluid past said valve member as said valve member opens to prevent a sudden cooling of the engine after the engine has already reached an initial warm condition. In one embodiment a safety catch is also provided to prevent the valve from closing even if an over-temperature event damages it.