Capacity Control Valve With Differential Pressure Discharge Path
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing capacity control valves face inefficiencies in responsiveness and operation efficiency during start-up and normal operation due to inadequate discharge of liquefied fluid from the control chamber, leading to differential pressure imbalances and reduced maximum capacity maintenance.
Innovation Solution
Incorporating a differential pressure valve that opens and closes communication between the control pressure and suction pressure ports, enhancing the flow path area for liquefied fluid discharge and maintaining equal pressures during start-up and operation, utilizing a solenoid-driven main valve element and pressure-sensitive valve with a differential pressure valve element.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a conventional capacity control valve is used with only a pressure-sensitive valve for fluid discharge, then the structure is simple, but the discharge of liquefied fluid from the control chamber is insufficient during start-up, leading to slow responsiveness
Solution Approach 1:
The capacity control valve is segmented into multiple functional valves: a pressure-sensitive valve for normal pressure control and a differential pressure valve specifically for rapid liquefied fluid discharge. This segmentation allows each valve to specialize in its optimal function, with the differential pressure valve providing additional discharge capability during start-up without complicating the normal operation control mechanism.
Solution Approach 2:
The differential pressure valve acts as an intermediary mechanism that activates specifically when differential pressure exceeds a threshold. It mediates between the high differential pressure condition (requiring rapid discharge) and the normal operation condition (maintained by the pressure-sensitive valve), providing rapid fluid discharge only when needed without interfering with normal pressure control.
2Productivity
If the flow path area for liquefied fluid discharge is increased during start-up, then responsiveness improves, but maintaining equal control and suction pressures becomes difficult during normal operation
Solution Approach 1:
The system dynamically adjusts the effective discharge area based on operating conditions. During start-up with high differential pressure, the differential pressure valve opens to maximize discharge area for rapid fluid removal. During normal operation when differential pressure is low, the differential pressure valve closes, reducing the effective discharge area to only what is needed for pressure balance maintenance by the pressure-sensitive valve.
Solution Approach 2:
The differential pressure valve operates based on feedback from the differential pressure between control and suction chambers. When differential pressure exceeds the threshold, the valve opens to increase discharge capacity. When differential pressure returns to normal range, the valve closes, automatically adjusting the system response based on real-time pressure conditions.
3Reliability
If the control pressure is maintained much higher than suction pressure during stop state, then fluid discharge capability is improved, but liquefied fluid accumulates in the control chamber, reducing maximum capacity
Solution Approach 1:
The differential pressure valve is designed to activate in advance during the transition from stop state to operation state, before the system reaches normal operating pressures. This preliminary action allows rapid discharge of accumulated liquefied fluid as soon as differential pressure builds up sufficiently, preventing capacity loss and ensuring quick transition to maximum capacity operation.
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 ensures rapid discharge of liquefied fluid during start-up, maintaining equal control and suction pressures, thereby improving responsiveness and operation efficiency by stabilizing the piston stroke and maximizing the control chamber's capacity.
Implementation Method 1
a main valve element which integrally includes a first valve portion coming into contact with and separating from the first valve seat in the first valve chamber so as to open and close a communication between the discharge chamber and the control chamber and a second valve portion coming into contact with and separating from the second valve seat in the second valve chamber so as to open and close a communication between the control chamber and the suction chamber and performs an opening and closing operation in the mutually opposite directions by the reciprocating movement
Implementation Method 2
a pressure-sensitive element 160 which is disposed inside the third valve chamber 140 and applies an urging force to the main valve element 151 in a valve opening direction of the main valve in response to an ambient fluid pressure
Implementation Method 3
the differential pressure valve including a differential pressure valve element and being capable of opening and closing a communication between the Pc port and the Ps port by the differential pressure valve element moved by an operation force of an operation member operated by a discharge pressure from the Pd port
Data Source
AI summary
A capacity control valve includes: a valve housing having a Pc port, a Ps port and a Pd port; a main valve element which includes a main valve portion coming contacting and separating from a main valve seat opening and closing communication between the Pd port and the Pc port by a drive force of a solenoid; an intermediate communication path communicating the Pc port with the Ps port; and a pressure-sensitive valve opening and closing the intermediate communication path by an ambient pressure, in which the valve housing have a differential pressure valve housed therein, the differential pressure valve including a differential pressure valve element and opening and closing a communication between the Pc port and the Ps port by the differential pressure valve element moved by an operation force of an operation member operated by a discharge pressure Pd from the Pd port.