Quick Coupler Hydraulic Circuit for Stable Attachment Locking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing quick coupler systems fail to stabilize the locked state of attachments due to the hydraulic pump not being driven when the operator is not actively using the switch, leading to instability in the attachment locking mechanism.

Innovation Solution

A quick coupler circuit that includes a coupler cylinder, actuator, first hydraulic pump, boosting valve, coupler changeover valve, and changeover switch, which allows for stable locking and unlocking of attachments by controlling the hydraulic fluid supply and pressure, ensuring consistent attachment security even when the operator is not actively operating the switch.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If the hydraulic pump is not driven when the switch is not operated, then fuel consumption is improved, but the locked state of the attachment cannot be stabilized

Engineering Contradiction:
Improvefuel consumptionVSAvoidlocked state stability
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The system dynamically adjusts the hydraulic pump operation mode based on the switch state. When the switch is operated, the pump runs continuously to maintain stable locking. When the switch is not operated, the pump stops to save fuel. This dynamic adaptation resolves the contradiction between energy efficiency and reliability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the operational parameters of the hydraulic pump based on system state. By switching between continuous operation (for stability) and stopped operation (for fuel efficiency), the system optimizes both fuel consumption and attachment locking stability under different conditions.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the hydraulic pump is driven continuously to stabilize the locked state, then attachment locking stability is improved, but fuel consumption increases

Engineering Contradiction:
Improvelocked state stabilityVSAvoidfuel consumption
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

Instead of continuous pump operation, the system uses periodic action by operating the pump only when needed (when the switch is activated). This periodic operation maintains attachment stability during critical moments while minimizing fuel consumption during idle periods.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The system provides self-service by maintaining attachment stability only when the operator actively requests it through switch operation. The pump runs on-demand to serve the immediate need for stability rather than continuously consuming fuel to maintain stability at all times.

Inventive Principle:
Principle #25Self-service

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 provides a stable locked state for attachments over extended periods, ensuring reliable attachment and detachment operations while maintaining efficient hydraulic fluid management.

Implementation Method 1

The first hydraulic pump is configured to be connected in parallel with the coupler cylinder and the actuator, and is configured to supply the hydraulic fluid to the coupler cylinder and the actuator

Methodology Applied
Scientific EffectHydraulic fluid supply: Hydraulic Press

Implementation Method 2

The boosting valve is configured to switch between a boosting position to raise a pressure of the hydraulic fluid supplied from the first hydraulic pump to the coupler cylinder

Methodology Applied
Scientific EffectPressure boosting: Pressure Increase

Data Source

PatentEP3546655B1Quick coupler circuit and quick coupler attachment/detachment method
Publication Date: 2022.07.13 KOMATSU LTD
  • EP3546655B1 patent drawingFigure 1
  • EP3546655B1 patent drawingFigure 2
  • EP3546655B1 patent drawingFigure 3

AI summary

In this quick coupler (20), a boosting valve (25) switches to a boosting position (Q1) and a coupler changeover valve (27) switches to a lock-side position (R1) when a changeover switch (28) switches to a lock position (S1). When the changeover switch (28) switches to a hold position (S2), the boosting valve (25) switches to a non-boosting position (Q2) and the coupler changeover valve (27) switches to the lock-side position (R1). When the changeover switch (28) switches to an unlock position (S3), the boosting valve (25) switches to the boosting position (Q1) and the coupler changeover valve (27) switches to an unlock-side position (R2).