Hollow Fan Ring Gearbox Cooling for Tight Installation Space

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Solution Overview

Problem

Existing gear cooling devices require significant space to achieve effective cooling of gearboxes, which can be a challenge in compact designs.

Innovation Solution

A gear cooling device that uses a hollow fan ring connected to a conveyor element to generate a cooling air flow through a suction jet effect, enhancing cooling capacity while minimizing space requirements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a fan is used to generate cooling air flow directly onto the gearbox housing, then cooling performance is achieved, but the device requires significant installation space

Engineering Contradiction:
Improvecooling performanceVSAvoidinstallation space
Core Design Contradiction:
TemperatureVSVolume of moving object

Solution Approach 1:

The patent introduces a hollow fan ring as an intermediary component between the conveying element and the gearbox housing. The fan ring receives operating flow from the conveying element and uses it to generate cooling air flow that acts on the gearbox housing. This intermediary structure enables the conveying element to be positioned at a distance from the housing, reducing space requirements while maintaining cooling effectiveness.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the conventional direct mechanical airflow generation (fan blowing air directly onto housing) with a fluid dynamic approach using the suction jet effect. The operating flow discharged through the fan ring creates a suction effect that entrains ambient air and directs it onto the gearbox housing, eliminating the need for direct mechanical contact and reducing installation space.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Productivity

If the conveying element is positioned close to the gearbox housing for direct cooling, then cooling efficiency is improved, but the conveying element comes into contact with other components

Engineering Contradiction:
Improvecooling efficiencyVSAvoidcomponent accessibility
Core Design Contradiction:
ProductivityVSEase of operation

Solution Approach 1:

The hollow fan ring serves as a mediator that transmits the cooling function from the conveying element to the gearbox housing without requiring the conveying element to be in direct proximity to the housing or other components. This allows the conveying element to be positioned in a less space-critical area where it can be easily installed and maintained.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Power

If a large volume flow of cooling air is generated, then cooling capacity increases, but the device requires larger installation space

Engineering Contradiction:
Improvecooling capacityVSAvoidinstallation space
Core Design Contradiction:
PowerVSVolume of moving object

Solution Approach 1:

The patent utilizes pneumatic principles, specifically the suction jet effect, to amplify the cooling air flow volume. The operating flow discharged through the fan ring creates a low-pressure region that entrains surrounding ambient air, multiplying the total volume flow of cooling air without requiring a proportionally larger conveying element or installation space.

Inventive Principle:
Principle #29Pneumatics and hydraulics

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 achieves a significantly higher cooling capacity compared to direct airflow methods, allowing for efficient cooling of gearboxes in compact spaces without the need for extensive installation space.

Implementation Method 1

the operating flow flowing out via the discharge opening generates the cooling air flow using a suction jet effect

Methodology Applied
Scientific EffectSuction jet effect: Jet

Implementation Method 2

a volume flow of the cooling air flow is composed at least by a volume flow of the operating flow and a volume flow of the ambient air entrained by the operating flow by the suction jet effect

Methodology Applied
Scientific EffectEntrainment: Entrainment

Implementation Method 3

The cooling air flow impinging on the outside of the transmission housing part for cooling a transmission

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP4377590B1Space saving transmission cooling device and transmission
Publication Date: 2025.05.07 FLENDER GMBH
  • EP4377590B1 patent drawingFigure 1
  • EP4377590B1 patent drawingFigure 2
  • EP4377590B1 patent drawingFigure 3

AI summary

The invention relates to a gearbox cooler device (35) provided with a gearbox housing part (30) to house rotating gearbox elements and a fan (34) connected to the gearbox housing part (30) to blow a cooling air stream (48) onto an outer face (32) of the gearbox housing (30). The fan (34) has a conveying element (36) communicating with a hollow fan ring (40) to generate an operating flow inside the fan ring (40), and the fan ring (40) communicates via at least one discharge opening (46) with a volume provided radially inside the fan ring (40) in such a way that the operating flow generates the cooling air stream (48) by means of a suction jet effect. With a large flow cross-section of the cooling air stream (48) and with a low installation space requirement, good cooling can be achieved by the indirect generation of the cooling air stream (48) with the aid of the operating flow generated by the conveying element (36) in the hollow fan ring (40), thus facilitating space-saving cooling of a gearbox (18).