Control Valve Spring Structure for Stable Shaft Friction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing vibration-proof springs in control valves for refrigeration systems experience unstable fixed states due to material deformation during manufacturing, affecting the precision of sliding friction, leading to vibration and noise issues in the valve elements.

Innovation Solution

A vibration-proof spring with a cylindrical shape, featuring a spring body supported by an inner wall and a cantilevered spring part with a protruding contact portion that warps to provide an elastic reactive force, is designed with edge parts that protrude radially outward to stabilize the spring in the mounting hole, ensuring precise sliding friction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a general press-forming process is used to manufacture the vibration-proof spring, then manufacturing cost and ease of manufacture are improved, but the fixed state becomes unstable due to material deformation, adversely affecting sliding friction precision

Engineering Contradiction:
Improveease of manufactureVSAvoidmanufacturing precision
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The invention changes the geometric parameters of the vibration-proof spring by adding edge parts that protrude radially outward from the cylindrical body. These edge parts engage with the mounting hole to prevent radial displacement and rotation of the spring, thereby stabilizing the fixed state and ensuring precise sliding friction characteristics while maintaining compatibility with press-forming manufacturing processes

Inventive Principle:
Principle #35Parameter changes

2Device complexity

If the vibration-proof spring is designed without edge parts, then device complexity is reduced, but the spring becomes unstable in the mounting hole, affecting sliding friction precision

Engineering Contradiction:
Improvedevice complexityVSAvoidreliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The invention applies local quality by adding edge parts only at specific locations on the cylindrical body of the vibration-proof spring. These localized protrusions engage with the mounting hole to provide stability and prevent displacement, while the rest of the spring structure remains simple and maintains its original vibration-damping function

Inventive Principle:
Principle #3Local quality

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 stabilizes the vibration-proof spring's fixed state, maintaining precise sliding friction on the shaft, effectively reducing vibrations and noise caused by refrigerant pressure fluctuations, enhancing the operating characteristics of the valve element.

Implementation Method 1

when the contact portion abuts against the shaft, the spring part is warped and an elastically reactive force resulting from the warped spring part gives a sliding force to the shaft

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

a cylindrically-shaped vibration-proof spring is provided in the mounting hole; this vibration-proof spring biases the shaft radially inward thereof so as to develop a sliding friction (resistance)

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3001124B1Control valve
Publication Date: 2019.11.06 TGK CO LTD
  • EP3001124B1 patent drawingFigure 1
  • EP3001124B1 patent drawingFigure 2A~2D
  • EP3001124B1 patent drawingFigure 3A~3E

AI summary

A vibration-proof spring (50), which coaxially inserts a shaft (33), is provided in a body of a control valve (1). The vibration-proof spring (50) includes a cylindrical spring body (102) supported by an inner wall of a larger-diameter part (46), spring parts (104), which are integrally formed with a side wall of the spring body (102) and are supported by the spring body (102) in a cantilevered manner, and bulging portions (106), which are formed, on surfaces of the spring parts (104) facing the shaft (33), in a protruding manner. In the vibration-proof spring (50), the spring parts (104) are warped when the bulging portions (106) abut against the shaft (33); an elastically reactive force resulting from the warped spring parts gives a sliding force to the shaft (33). The spring body (102) is formed as a cylindrical body such that a plate-like body, which is obtained by punching a metallic plate through a press-forming process, is bent along a longitudinal direction of the plate-like body. Also, the spring body (102) is formed in such a manner as to have edge parts (120) that protrude radially outward from at least one of ends of the cylindrical body in the direction of axis line.