Compressor Capacity Control Valve With Startup-Only CS Flow Path

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing capacity control valves for variable displacement compressors suffer from poor controllability and operation efficiency due to refrigerant flow from the control port into the suction port during continuous driving, leading to deteriorated performance.

Innovation Solution

A capacity control valve design featuring a primary valve and a CS valve with opposing springs, allowing the control port to communicate with the suction port only during startup and maximum energized states, while maintaining equal pressures to enhance discharge efficiency and prevent fluid flow into the suction area.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the auxiliary communication path is formed to communicate control port and suction port, then responsiveness at startup is improved, but controllability deteriorates during continuous driving due to refrigerant flow from control port to suction port

Engineering Contradiction:
ImproveresponsivenessVSAvoidcontrollability
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The communication path is segmented into two distinct valves: a primary valve for normal control operations and a CS valve for startup/maximum capacity operations. This segmentation allows each valve to be optimized for its specific function, with the CS valve providing a dedicated communication path between control port and suction port only when needed, while the primary valve maintains precise controllability during continuous driving without unwanted refrigerant flow.

Inventive Principle:
Principle #1Segmentation

2Productivity

If the primary valve is closed to decrease control chamber pressure for maximum capacity, then discharge amount increases, but refrigerant flows into suction port causing poor controllability

Engineering Contradiction:
Improvedischarge amountVSAvoidcontrollability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The CS valve acts as an intermediary component that provides a controlled communication path between the control port and suction port. When the primary valve is closed for maximum capacity operation, the CS valve mediates the pressure equalization process, allowing refrigerant to flow in a controlled manner to prevent suction port contamination while maintaining the desired discharge amount and controllability.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 design improves the operational efficiency and discharge performance of the variable displacement compressor by maintaining equal control and suction pressures, ensuring effective refrigerant discharge and reducing fluid flow issues during startup and continuous operation.

Implementation Method 1

a valve body is moved in the axial direction by an electromagnetic force generated in a solenoid

Methodology Applied
Scientific EffectElectromagnetic force: Electromagnet

Implementation Method 2

a first spring configured to urge the CS valve body in a closing direction of the CS valve, and a second spring configured to urge the CS valve body in an opening direction of the CS valve

Methodology Applied
Scientific EffectElastic reaction force: Spring

Implementation Method 3

a pressure drive valve which is opened and closed by the suction pressure

Methodology Applied
Scientific EffectPressure: Pressure Increase

Data Source

PatentEP3822482B1Capacity control valve
Publication Date: 2023.08.16 EAGLE INDS
  • EP3822482B1 patent drawingFigure 1
  • EP3822482B1 patent drawingFigure 2
  • EP3822482B1 patent drawingFigure 3

AI summary

To provide a capacity control valve having good operation efficiency while having a fluid discharge function at startup. A capacity control valve V includes a valve housing 10 provided with a discharge port 12 allowing a discharge fluid of a discharge pressure Pd to pass therethrough, a suction port 15 allowing a suction fluid of a suction pressure Ps to pass therethrough, and control ports 13 and 14 allowing a control fluid of a control pressure Pc to pass therethrough, rods 52 and 54 driven by a solenoid 80, and a primary valve 50 including a primary valve seat 10a and a primary valve body 51 and opens and closes a communication between the discharge port 12 and the control port 13 by the movement of the rods 52 and 54. The capacity control valve V further includes a CS valve 56 which opens and closes a communication between the control fluid and the suction fluid by the movement of the rods 52 and 54 and an urging member 91 configured to urge the primary valve body 51 and the rods 52 and 54 in opposite directions and the primary valve body 51 and the rods 52 and 54 are disposed so as to be relatively movable in an axial direction.