accumulator
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Solution Overview
Problem
Conventional accumulators for heat pump systems require complex configurations and additional components to manage oil return efficiently, especially when the oil and refrigerant form separate layers due to differences in specific gravity, leading to reduced operation efficiency during low-load operations.
Innovation Solution
An accumulator design featuring a floating member on the outer periphery of the outlet pipe that slides vertically with the oil surface level, incorporating a slit hole and oil return hole that open only when the oil level exceeds a predetermined threshold, allowing for increased oil return to the compressor without additional moving parts or complex controls.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional accumulator design with fixed outlet pipe and single oil return hole is used, then the structure is simple, but oil return efficiency decreases when oil forms an upper layer during low-load operations
Solution Approach 1:
The outlet pipe is designed to move vertically within the tank along a guide member, allowing its position to dynamically adjust based on the oil layer height. This dynamic positioning enables the outlet pipe to maintain optimal communication with the oil layer regardless of whether oil has accumulated as an upper layer during low-load operations or not during high-load operations, thereby maintaining reliable oil return efficiency without requiring complex additional components
Solution Approach 2:
The accumulator utilizes the system's own operational variations (load changes causing oil level fluctuations) to automatically position the outlet pipe at the correct height through the guide member mechanism. The system self-adjusts based on natural convection and oil accumulation patterns without requiring external control systems, sensors, or additional moving parts beyond the guide member
2Reliability
If additional components are added to improve oil return during two-layer separation, then oil return efficiency improves, but device complexity increases
Solution Approach 1:
The guide member serves multiple functions: it guides the vertical movement of the outlet pipe, constrains the pipe's position to prevent lateral displacement, and enables the outlet pipe to adapt to different operational conditions. This single component performs what would otherwise require multiple separate mechanisms, improving oil return consistency during two-layer separation while minimizing the increase in device complexity
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 enhances oil return efficiency, simplifies the accumulator configuration, reduces component count, and improves heating efficiency by ensuring consistent oil return even during two-layer separate states, while using materials with lower specific gravity than the oil to enhance buoyancy and reduce turbulence.
Implementation Method 1
the floating member being adapted to move up or down according to change in an oil surface level with buoyancy received from oil included in the refrigerant
Implementation Method 2
A refrigerant in a gas-liquid mixed state introduced into the accumulator collides with the gas-liquid separator and is radially diffused to be separated into a liquid-phase refrigerant and a gas-phase refrigerant
Implementation Method 3
Oil that has accumulated in the lower portion of the tank together with the liquid-phase refrigerant moves toward the bottom of the tank due to the difference in specific gravity, properties, and the like between the oil and the liquid-phase refrigerant
Data Source
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AI summary
Provided is an accumulator with a simple and inexpensive structure capable of increasing an oil return amount and improving the operation efficiency of a system even when a tank of the accumulator has a large liquid portion including a liquid-phase refrigerant and oil accumulated therein and the liquid portion is in a two-layer separate state (i.e., an oil layer on the upper side and a liquid-phase refrigerant layer on the lower side) with use of the oil that is not compatible with the refrigerant and has a lower specific gravity than the refrigerant, thus forming the oil layer in the upper position inside of the tank of the accumulator, for example. A floating member 20 is disposed on the outer periphery of an outlet pipe 30 so as to be slidable in a vertical direction. The floating member 20 is adapted to move up or down according to change in an oil surface level with buoyancy received from the oil included in the refrigerant, and is provided with an oil return hole 25 in a portion to be immersed in the oil. The outlet pipe 30 is provided with a slit hole 39 extending in the vertical direction. The slit hole 39 is adapted to be continuous with the oil return hole 25 when the oil surface level exceeds a predetermined level.