Capacity Control Valve Throttling for Fast Compressor Start-Up
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional capacity control valves for variable capacity compressors suffer from decreased operating efficiency due to uncontrolled refrigerant gas flow from the control chamber to the suction chamber, even after liquefied refrigerant has been discharged, leading to prolonged start-up times and reduced control responsiveness.
Innovation Solution
A capacity control valve with a throttle valve portion that narrows the communication hole significantly after initial valve opening, and an induction hole to regulate control chamber pressure sensitivity to suction chamber pressure changes, ensuring efficient refrigerant discharge and maintaining high compressor efficiency during operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the communication hole is kept open after liquefied refrigerant discharge, then the start-up time is reduced, but the operating efficiency decreases due to uncontrolled refrigerant gas flow
Solution Approach 1:
The throttle valve portion is designed to dynamically change the opening degree of the communication hole based on the stroke position of the valve element. During initial discharge, the hole is fully open for rapid refrigerant evacuation. During subsequent control operations, the hole opening is reduced to throttle gas flow and maintain operating efficiency. This dynamic adjustment resolves the contradiction between fast start-up and energy efficiency.
Solution Approach 2:
The patent changes the flow resistance parameter of the communication hole by varying the throttle valve opening degree. The opening degree is controlled as a function of valve element stroke, transitioning from a fully open state (low resistance) during discharge to a partially closed state (high resistance) during control operations. This parameter change enables both rapid start-up and efficient operation.
2Loss of energy
If the throttle valve portion narrows the communication hole significantly, then the refrigerant gas flow is controlled, but the discharge rate of liquefied refrigerant slows down
Solution Approach 1:
The system dynamically adjusts the communication hole opening based on operational phase. During the discharge phase, the throttle valve is fully open to maximize discharge rate. During the control operation phase, the throttle valve narrows the opening to control gas flow and maintain efficiency. This temporal separation of functions resolves the contradiction between discharge rate and operating efficiency.
Solution Approach 2:
The throttle valve portion is designed to be fully open during the initial discharge phase before control operations begin. This preliminary open state ensures maximum discharge rate for rapid refrigerant evacuation. Only after discharge is complete does the valve narrow to control gas flow, ensuring that the narrowing action does not impede the critical discharge function.
3Speed
If the communication hole is fully open during control operation, then the refrigerant discharge is rapid, but the control responsiveness deteriorates
Solution Approach 1:
The throttle valve portion dynamically adjusts the communication hole opening degree based on valve element stroke position. During discharge operations, the hole remains fully open for rapid refrigerant flow. During control operations, the hole opening is reduced to throttle gas flow and improve control responsiveness. This dynamic behavior resolves the contradiction between discharge speed and control responsiveness.
Solution Approach 2:
The patent changes the flow area parameter of the communication hole based on operational requirements. The opening degree is controlled as a function of valve element stroke, transitioning from maximum opening (high flow area) during discharge to reduced opening (low flow area) during control. This parameter change enables both rapid discharge and responsive control.
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 enables rapid discharge of liquefied refrigerant and maintains high operating efficiency by throttling refrigerant gas flow, thereby shortening start-up times and improving control responsiveness of the variable capacity compressor.
Implementation Method 1
a solenoid S exerting an electromagnetic driving force on the valve element 181
Implementation Method 2
a pressure-sensitive element (a bellows) 178 disposed in the first valve chamber, exerting a biasing force in a direction of extension (expansion) and contracting in accordance with an increase in pressure in its environment
Data Source
AI summary
A capacity control valve is provided with a throttle valve portion having a communication hole and a second valve hole. The communication hole is provided between a second valve portion and a third valve portion and makes an intermediate communication passage communicate with a third valve chamber. The second valve hole is provided between a second valve chamber and the third valve chamber. An amount of narrowing of the throttle valve portion in relation to a stroke of a valve element is set larger when the second valve portion initially opens by separating from a second valve seat face, and then becomes narrower after the initial opening of the valve. The capacity control valve is capable of shortening a start-up time and improving the operating efficiency of a variable capacity compressor.