Variable Displacement Compressor Valve Startup Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional displacement control valves for variable displacement compressors experience reduced operating efficiency due to unnecessary refrigerant gas flow from the control chamber into the suction chamber, especially during startup, which prolongs startup time and reduces efficiency.
Innovation Solution
The displacement control valve is designed with a third valve section opening area that is smaller than the auxiliary communicating passage area, reducing the minimum flow path area between the control and suction pressures, and positioning the auxiliary communicating passage in the first valve chest under control pressure, with the pressure-sensitive element and third valve section acting under suction pressure to optimize liquid refrigerant discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the third valve section opening area is increased to improve refrigerant discharge speed, then startup time is reduced, but operating efficiency deteriorates due to unnecessary refrigerant gas flow from control chamber to suction chamber
Solution Approach 1:
The third valve section is designed to dynamically adjust its opening area based on operating conditions. During startup, the valve opens wider to accelerate refrigerant discharge. During normal operation, the valve maintains a smaller opening area to prevent unnecessary refrigerant gas flow from the control chamber to the suction chamber, thereby optimizing operating efficiency while maintaining fast startup capability
Solution Approach 2:
The invention changes the opening area parameter of the third valve section from a fixed value to a variable value that adapts to different operational states. By controlling the valve opening area to be smaller than the auxiliary communicating passage area during operation, the system achieves both fast startup (through the auxiliary passage) and high operating efficiency (through restricted flow during normal operation)
2Speed
If the auxiliary communicating passage area is increased to accelerate liquid refrigerant vaporization, then startup performance is improved, but refrigerant gas leakage during operation increases
Solution Approach 1:
The invention extracts the refrigerant discharge function into a separate auxiliary communicating passage, independent of the third valve section. This allows the auxiliary passage to be optimized for fast vaporization during startup without compromising operating efficiency, as the third valve section separately controls refrigerant gas flow during normal operation
Solution Approach 2:
The refrigerant flow control system is segmented into two independent pathways: the auxiliary communicating passage for rapid liquid refrigerant discharge during startup, and the third valve section for controlled refrigerant gas flow during operation. This segmentation allows each pathway to be optimized for its specific function without interfering with the other
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
This configuration reduces startup time and improves operating efficiency by minimizing the Pc-Ps flow path area, allowing faster vaporization of refrigerant liquid and maintaining efficient compressor control.
Implementation Method 1
a pressure-sensitive element (bellows) 78 that is disposed in the first valve chest and exerts a biasing force in the extending (expanding) direction and contracts with an increase in ambient pressure
Implementation Method 2
a solenoid S that exerts an electromagnetic drive force on the valve element 81
Data Source
Figure 1
Figure 2(a)~2(c)
Figure 3
AI summary
A displacement control valve improved in the function of discharging liquid refrigerant in a control chamber at startup achieves a reduction in startup time and an improvement in operating efficiency during control of a variable displacement compressor simultaneously. The opening area S2 between communicating holes 23 in a third valve section 21A and a third valve seat surface 12 in a control area to control the flow rate or pressure in a working control chamber is set smaller than the area S1 of auxiliary communicating passages 21E.