Bucket Return-To-Dig Control With Soft Stop Priority Logic

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The presence of return to function (RTF) and soft stop functionalities in work vehicles, such as wheel loaders, often conflict, reducing productivity and user ergonomics, necessitating an improvement in RTF comfort and efficiency.

Innovation Solution

A control system that integrates a hydraulic circuit with a proportional six-way three-position valve, an electronic control unit, and sensor means to prioritize the return to dig functionality over soft stop when the joystick is released, eliminating the need for manual activation of these functions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If both return to function (RTF) and soft stop functionalities are provided in the work vehicle, then the operational flexibility is improved, but the system complexity and operational conflict increase

Engineering Contradiction:
Improveoperational flexibilityVSAvoidsystem complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges the RTF and soft stop functionalities into a unified control system where the electronic control unit integrates both functions. The control system automatically determines whether to execute RTF or soft stop based on joystick position and vehicle state, eliminating the need for separate independent control mechanisms and reducing overall system complexity while maintaining operational flexibility.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The electronic control unit is designed to perform multiple functions - it can execute both RTF (return to dig) and soft stop operations depending on the operational context. This multi-functionality allows a single control system to adapt to different operational requirements without requiring separate dedicated systems for each function.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If both return to function (RTF) and soft stop functionalities are provided in the work vehicle, then the operational flexibility is improved, but the productivity decreases due to functional conflicts

Engineering Contradiction:
Improveoperational flexibilityVSAvoidproductivity
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The control system performs preliminary assessment of the operational context by monitoring joystick position, vehicle state, and active functions before executing any return operation. This preliminary action allows the system to pre-determine the appropriate function (RTF or soft stop) to execute, avoiding conflicts and ensuring smooth, uninterrupted operations that maintain productivity.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system dynamically switches between RTF and soft stop functionalities based on real-time operational conditions. The electronic control unit continuously evaluates the current state and automatically selects the most appropriate function, making the system adaptive and responsive to changing operational requirements without manual intervention or productivity loss.

Inventive Principle:
Principle #15Dynamics

3Measurement precision

If manual activation of return to function is required, then the control precision is improved, but the ease of operation deteriorates

Engineering Contradiction:
Improvecontrol precisionVSAvoidease of operation
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The control system provides self-service by automatically determining when and which function (RTF or soft stop) to execute based on monitored operational parameters. The system serves itself by making intelligent decisions about function activation without requiring manual user input, thereby improving ease of operation while maintaining control precision through sensor-based detection and electronic control.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system uses feedback from sensors monitoring joystick position, vehicle state, and active functions to automatically determine the appropriate return function to execute. This feedback mechanism allows the system to maintain precise control by continuously monitoring operational context while eliminating the need for manual activation, thereby improving ease of operation.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP4234817B1Improved system and method for controlling a return functionality in a work vehicle
Publication Date: 2025.01.01 CNH IND ITALIA SPA
  • EP4234817B1 patent drawingFigure 1

AI summary

Work vehicle comprising an implement provided with at least a bucket comprising a control system (1) for controlling the movement of said implement and comprising a valve arrangement (6), a bucket actuator (3), an electronic control unit (10), a joystick (8) and a command means (12) for activating a return to dig, RTD, of the implement, the electronic control unit (10) being electrically connected to the valve arrangement (6) and to the command and to retrieve data related to the joystick (8) and data (9) related to engine speed of the work vehicle, the electronic control unit (10) comprising elaboration means configured to - activate a RTD operation of said implement according to an enabling status of the command of the command means (12), - activate a soft stop function of the implement if it is detected a release of the joystick, the soft stop function foreseeing an automatic smooth movement of the implement till a preset stop position, the soft stop function being inhibited if the RTD operation is active.