Actuator Device Auxiliary Frame Segmentation for Safe Positioning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing actuators, when coupled to valves, fail to reliably switch to a safe position upon loss of power, particularly because auxiliary frames can only be biased when the valve spindle is in the upper position, limiting their functionality.

Innovation Solution

An actuator design featuring a motor spindle engaged with an actuator spindle via a nut, with an auxiliary frame that can be displaced and biased by the motor, and releasably coupled to the actuator housing, allowing independent displacement of the actuator spindle, and a coupling mechanism with grooves and locking bodies that facilitate easy disengagement, enabling the actuator spindle to move to a retracted position regardless of the motor spindle's position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the auxiliary frame is biased by compressing a spring while the valve spindle is in the upper position, then the valve can be moved to the safe closed position upon power loss, but the auxiliary frame cannot be biased unless the valve spindle is in the upper position, limiting its functionality

Engineering Contradiction:
Improveability to switch to safe position upon power lossVSAvoidfunctionality of auxiliary frame
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The coupling mechanism is divided into two independent couplings: a first coupling between the nut and actuator spindle, and a second coupling between the auxiliary frame and actuator housing. This segmentation allows the auxiliary frame to be biased and locked independently of the valve spindle position, enabling the auxiliary frame to function regardless of whether the spindle is in the upper or lower position.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The auxiliary frame can be biased by the motor in advance during normal operation, and the locking mechanism is prepared to engage at any position. This preliminary action ensures that when power is lost, the auxiliary frame is already in the correct biased state to move the valve to the safe position, without requiring the spindle to be in a specific position beforehand.

Inventive Principle:
Principle #10Preliminary action

2Strength

If the locking body is prevented from displacing out of engagement by a locking ring, then the coupling remains securely engaged, but the coupling requires complex mechanisms to achieve disengagement

Engineering Contradiction:
Improveengagement strength of couplingVSAvoidease of coupling disengagement
Core Design Contradiction:
StrengthVSEase of operation

Solution Approach 1:

The locking ring is designed to rotate about its axial center line, transforming the static locking mechanism into a dynamic one. By rotating the locking ring, the recesses align with the locking bodies, allowing them to disengage. This dynamic mechanism maintains strong engagement during normal operation while enabling easy disengagement through rotation, eliminating the need for complex release mechanisms.

Inventive Principle:
Principle #15Dynamics

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

Ensures the actuator spindle can be reliably displaced to a safe position even without power, enhancing the actuator's functionality and reliability by allowing the auxiliary frame to bias the spindle independently of the motor, and reducing the torque required for coupling disengagement.

Implementation Method 1

The nut is releasably coupled to the actuator spindle, thereby being arranged to bias the auxiliary frame while disengaged from the actuator spindle

Methodology Applied
Scientific EffectMechanical biasing force: Mechanical Force

Implementation Method 2

A locking ring that encircles the retainer ring prevents the locking body from displacing out of engagement with the cylindrical body. The locking ring is provided with at least one recess which can be brought into a corresponding position relative to the locking body when the locking ring is rotated

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP1931900B1Actuator device
Publication Date: 2018.10.17 VETCO GRAY SCANDINAVIA
  • EP1931900B1 patent drawingFigure 1
  • EP1931900B1 patent drawingFigure 2
  • EP1931900B1 patent drawingFigure 3

AI summary

An actuator device (1) comprising an actuator housing (2), a driving motor (4) attached to the actuator housing (2), which driving motor (4) is provided with a motor spindle (28), the motor spindle (28) being displaceably engaged with an actuator spindle (6) via a nut (38), and where an auxiliary frame (8) which can be displaced relative to the actuator spindle (6) and biased by use of the driving motor (4), and which can be releasably coupled to the actuator housing (2), is arranged to displace the actuator spindle (6) independently of the motor (4), and where the nut (38) is releasable coupled to the actuator spindle (6), thereby being arranged to bias the auxiliary frame (8) while disengaged from the actuator spindle (6).