Fluid Arrangement for Clutch and Gear Actuation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing fluid arrangements for actuating clutches and transmission components with fluid energy sources are complex and require multiple components, making them difficult to simplify and efficiently control.

Innovation Solution

A fluid arrangement using a dual-pressure valve system connects a fluid reservoir to both the transmission and clutch sides, allowing pressure to be applied on one side at a time, with dead volumes acting as hydraulic cylinders to ensure synchronized actuation and prevent undesired pressure reductions, and valve devices functioning as non-return valves to maintain pressure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a fluid pump is used to actuate both clutch and transmission component, then the actuation system becomes more integrated, but it becomes difficult to prevent premature engagement and control actuation timing

Engineering Contradiction:
Improveactuation controlVSAvoidengagement timing
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The fluid arrangement is segmented into separate dead volumes for clutch actuation and transmission component actuation. Each dead volume is controlled by its own valve device, allowing independent control of actuation timing and preventing premature engagement while maintaining system integration.

Inventive Principle:
Principle #1Segmentation

2Speed

If pressure is applied continuously to actuate components, then actuation speed is improved, but undesired pressure reductions and premature engagement occur

Engineering Contradiction:
Improveactuation speedVSAvoidpressure maintenance
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The valve devices operate periodically to apply pressure to the dead volumes only when needed for actuation. The non-return valve functionality maintains pressure during actuation and prevents undesired pressure reductions, enabling fast actuation without premature engagement.

Inventive Principle:
Principle #19Periodic action

3Manufacturing precision

If multiple valve devices are used to control fluid flow, then actuation precision is improved, but device complexity increases

Engineering Contradiction:
Improveactuation precisionVSAvoidvalve system complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The valve devices are integrated into the fluid arrangement with the pump and dead volumes. Each valve device combines non-return valve functionality with pressure control, reducing the need for separate components and simplifying the overall system while maintaining precise actuation control.

Inventive Principle:
Principle #5Merging (Combining)

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 simplifies the actuation process by ensuring that clutches and transmission components are only actuated when desired, preventing premature engagement and maintaining pressure, thus enhancing operational efficiency and reliability.

Implementation Method 1

a fluid pump with a first conveying direction in which the fluid pump serves to actuate the transmission component on a transmission side and with a second conveying direction opposite the first conveying direction in which the fluid pump serves to actuate the clutch on a clutch side

Methodology Applied
Scientific EffectHydraulic pressure: Pressure Gradient

Implementation Method 2

at least one dead volume can be provided on the transmission side and on the clutch side. The dead volume acts like a hydraulic cylinder with a hydraulic piston that has an end stop in both directions of movement

Methodology Applied
Scientific EffectHydraulic cylinder principle: Hydraulic Press

Data Source

PatentEP3084273B1Fluid arrangement
Publication Date: 2018.08.01 SCHAEFFLER TECHNOLOGIES AG & CO KG
  • EP3084273B1 patent drawingFigure 1
  • EP3084273B1 patent drawingFigure 2
  • EP3084273B1 patent drawingFigure 3

AI summary

The invention relates to a fluid arrangement for the fluidic actuation of at least one clutch and at least one gear component, having a fluidic energy source. The invention is characterized in that the fluidic energy source comprises a fluid pump having a first direction of flow in which the fluid pump is used on a gear side to actuate the gear component, and a second direction of flow, which is opposite the first direction of flow and in which the fluid pump is used on a clutch side to actuate the clutch .