Integrated Locking in Double-Acting Hydraulic Cylinders

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing double-acting hydraulic cylinders have large overall dimensions, complex oil circuits, and require cumbersome blocking valves that lead to response delays and safety concerns due to high oil pressures and the need for multiple fittings, which can result in accidental machine operation.

Innovation Solution

A compact, lockable hydraulic cylinder design with an integrated locking device that allows for zero response delay, featuring a parallelepiped-shaped cylinder with internal hydraulic circuits and a removable locking device that is easy to assemble and maintain, eliminating the need for external blocking valves and reducing overall dimensions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If external blocking valves are used to control oil flow, then the hydraulic cylinder can be regulated, but the overall dimensions become large and response delay increases

Engineering Contradiction:
Improvecontrol reliabilityVSAvoidoverall dimensions
Core Design Contradiction:
ReliabilityVSLength of stationary object

Solution Approach 1:

The locking device is integrated directly into the cylinder body, merging the blocking function with the cylinder structure. This eliminates the need for separate external blocking valves and reduces the overall system dimensions while maintaining control reliability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The locking device is nested within the cylinder body, with the locking pin moving inside the cylinder chamber. This nested arrangement allows the blocking function to be contained within the existing cylinder footprint, reducing overall dimensions.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Reliability

If external blocking valves are used, then oil flow can be blocked, but the response delay between control and plunger action increases

Engineering Contradiction:
Improveblocking accuracyVSAvoidresponse delay
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The locking device is positioned at the same location as the piston, merging the control and execution functions. This eliminates the time delay caused by oil traveling through long ducts to external blocking valves, achieving immediate response when locking is activated.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The locking pin is pre-positioned within the cylinder chamber, ready to engage with the piston. When activation occurs, the locking pin can immediately engage without requiring oil to travel through external circuits, reducing response delay.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If multiple fittings and external blocking valves are used, then oil flow control is achieved, but the system complexity and risk of leakage increase

Engineering Contradiction:
Improveflow control capabilityVSAvoidcircuit complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The locking device integrates the blocking function directly into the cylinder body, eliminating the need for multiple external fittings and valves. This reduces system complexity and the number of potential leakage points while maintaining flow control capability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The blocking function is extracted from the external circuit system and incorporated directly into the cylinder. This removes the need for separate blocking valves and associated fittings, simplifying the overall system.

Inventive Principle:
Principle #2Taking out (Extraction)

4Object-affected harmful factors

If blocking valves are positioned at a distance from the cylinder, then safety from impact is improved, but the response delay increases

Engineering Contradiction:
Improveoperator safetyVSAvoidresponse delay
Core Design Contradiction:
Object-affected harmful factorsVSLoss of time

Solution Approach 1:

The locking device is merged with the cylinder assembly, positioned safely within the protected enclosure. This eliminates the need to position blocking valves at a distance for safety, while achieving immediate response due to the integrated positioning.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The locking device is nested within the cylinder body, which itself is enclosed in a protected structure. This nested arrangement provides safety through enclosure while maintaining close positioning for rapid response.

Inventive Principle:
Principle #7Nested doll (Nesting)

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 safe, cost-effective, and highly functional hydraulic cylinder with reduced overall dimensions and low response delay, enhancing operational safety and ease of maintenance by integrating the locking mechanism within the cylinder.

Implementation Method 1

the circuits in proximity of the blocking valve require a minimum radius of curvature due to the high oil pressures inside the ducts

Methodology Applied
Scientific EffectHydraulic pressure: Pressure Increase

Implementation Method 2

The sliding of the plunger may be promoted by a working fluid, for example oil, in a per se known manner

Methodology Applied
Scientific EffectHydraulic actuation: Hydraulic Press

Data Source

PatentEP4074985A1Double-acting hydraulic cylinders
Publication Date: 2022.10.19 OLEODINAMICA IMPIANTI SRL
  • EP4074985A1 patent drawingFigure 1~2B
  • EP4074985A1 patent drawingFigure 3~4
  • EP4074985A1 patent drawingFigure 5~6

AI summary

A double-acting hydraulic cylinder which can be connected to means for supplying and discharging a working fluid, comprising a jacket (10) internally comprising a working chamber (30) having a longitudinal extension defining an axis (X) and a plunger (20) sealingly inserted into the jacket (10) to partition said working chamber (30) into at least one first and second variable volume half-chamber (100, 200). The plunger (20) and the jacket (10) are mutually slidable along the axis (X) between at least one first operative position and a second operative position. The cylinder includes a locking device (500) for blocking the mutual sliding of the plunger (20) and of the jacket (10) which can be removably inserted into the jacket (10).