Air-Cooled Dry Brake for Straddle Carrier Hoist

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing straddle carriers for container terminals require significant design and technical effort due to the use of oil-disk brakes in their hoisting mechanisms, which are complex and costly.

Innovation Solution

The implementation of an air-cooled dry brake, specifically an air-cooled spring brake, on the high-speed side of the transmission between the drive unit and hoist winches, utilizing standard mass-produced components, and the use of high-power density torque motors with vibration or buffer elements to reduce mechanical stress and noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If oil-disk brakes are used in the hoisting mechanism, then reliable braking function is achieved, but design and technical effort increases significantly

Engineering Contradiction:
Improvebraking functionVSAvoiddesign and technical effort
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical oil-disk brake system with a pneumatic spring brake system. The pneumatic spring brake uses compressed air to activate spring-loaded braking elements, eliminating the need for oil-based hydraulic systems while maintaining reliable braking function. This substitution reduces design complexity and technical effort required for the hoisting mechanism.

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

Solution Approach 2:

The patent changes the braking mechanism from oil-based to pneumatic-based, fundamentally altering the operational parameter from hydraulic pressure to pneumatic pressure. This parameter change enables the use of spring-loaded braking elements that are simpler in design and require less technical effort to implement while maintaining effective braking performance.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If air-cooled dry brake is used on the high-speed side of transmission, then standard mass-produced components can be used, but braking torque control becomes more challenging

Engineering Contradiction:
Improvestandard component usageVSAvoidtorque control
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The patent introduces a gear transmission system as an intermediary between the air-cooled dry brake and the hoist winch. The brake is positioned on the high-speed side of the gear, and the gear transmission multiplies the braking torque to achieve the required control on the low-speed side. This intermediary mechanism enables the use of standard mass-produced brake components while maintaining effective torque control.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Length of moving object

If high-power density torque motors are used, then hoist width is reduced to 3,500 mm, but motor design complexity increases

Engineering Contradiction:
Improvehoist widthVSAvoidmotor design
Core Design Contradiction:
Length of moving objectVSDevice complexity

Solution Approach 1:

The patent employs high-power density torque motors that operate at below 1,400 rpm with power density above 0.35 kW/kg. By changing the operational parameters (speed and power density) and using permanently excited synchronous motor technology, the motor achieves compact dimensions that reduce the overall hoist width to approximately 3,500 mm, enabling conventional transportation without special security measures.

Inventive Principle:
Principle #35Parameter changes

4Strength

If vibration or buffer elements are added to hoisting winches, then mechanical stress on frame is reduced, but device complexity increases

Engineering Contradiction:
Improveframe stressVSAvoidvibration elements
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent incorporates vibration or buffer elements on the straddle carrier-side bearings of the hoisting winches before mechanical stress can be transmitted to the frame. These elements act as pre-positioned cushioning mechanisms that absorb and dampen vibrations and mechanical shocks, protecting the frame from excessive stress while adding minimal complexity to the overall system.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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 reduces the structural and technical complexity of the hoisting mechanism, allows for standard component usage, and minimizes noise pollution, enabling the hoist to be transported conventionally without special security measures and reducing mechanical stress on the straddle carrier.

Implementation Method 1

the braking device between the drive unit and the hoist winches of the hoist of the straddle carrier according to the invention is designed as an air-cooled dry brake

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

air-cooled dry brake

Methodology Applied
Scientific EffectAir cooling: Convection

Implementation Method 3

the hoisting winches are provided with vibration or buffer elements on their straddle carrier-side bearings, by means of which the hoisting winches and the straddle carrier or its frame are vibration-decoupled. Apart from avoiding mechanical stresses on the frame, sound decoupling can also be realized to a large extent in this way

Methodology Applied
Scientific EffectVibration damping: Damping

Implementation Method 4

vibration or buffer elements on their straddle carrier-side bearings, by means of which the hoisting winches and the straddle carrier or its frame are vibration-decoupled

Methodology Applied
Scientific EffectVibration decoupling: Vibration

Data Source

PatentEP2490976B1Straddle carrier for use in container terminals and for general transport tasks
Publication Date: 2014.07.30 PFENNING ELEKTROANLAGEN
  • EP2490976B1 patent drawingFigure 1
  • EP2490976B1 patent drawingFigure 2
  • EP2490976B1 patent drawingFigure 3

AI summary

The invention relates to a straddle carrier (1) for use in container terminals and for general transport tasks, comprising a frame (2), a load-receiving means (4), which hangs between the frame (2) and can be locked together with a load, preferably a container (7), travel supports (3), which are arranged at the lower area of the frame (2) and each comprise a plurality of wheels (11) arranged in a row, and a lifting unit (8), by means of which the load-receiving means (4) can be moved vertically and which comprises lifting winches and at least one drive unit, wherein a brake device is arranged between the lifting winches and the at least one drive unit. In order to allow standard components that can be produced in large quantities and that have high operational reliability to be used for the brake device, the brake device is designed as an air-cooled dry brake and sits on the fast side of a transmission arranged between the drive unit and the lifting winch.