Sensor-integrated expansion valve
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicular air conditioners face issues with refrigerant leakage through the sensor hole, leading to corrosion and damage of sensor circuit boards, electrical short-circuiting, and reduced cooling performance due to the close proximity of the PT sensor and expansion valve.
Innovation Solution
A sensor-integrated expansion valve design that includes a PT sensor with a thread fastening assembly and an O-ring to enhance fastening and sealing, along with elastic contact terminals for consistent electrical connection, preventing refrigerant leakage and ensuring easy assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the PT sensor is installed close to the expansion valve to shorten assembly time and reduce costs, then assembly efficiency is improved, but refrigerant leakage through the sensor hole causes corrosion and electrical short-circuiting
Solution Approach 1:
A non-refrigerant-permeable seal member (O-ring) is introduced as an intermediary element between the sensor hole and the refrigerant flow path. This seal member prevents refrigerant from reaching the sensor circuit board and electrical connections, thereby eliminating the harmful effect of refrigerant leakage while maintaining the close integration of the PT sensor with the expansion valve for efficient assembly
2Device complexity
If the PT sensor is integrated into the expansion valve to improve post-assembly management and reduce costs, then system integration is improved, but the complexity of sealing and electrical connection increases
Solution Approach 1:
The integrated sensor assembly is divided into distinct functional segments: a sensor mounting portion with threaded engagement for mechanical fastening, a seal member portion (O-ring) for refrigerant isolation, and an electrical connection portion with contact terminals. This segmentation allows each component to be manufactured and assembled separately using standard processes, reducing manufacturing complexity while achieving full integration
Solution Approach 2:
The sensor mounting portion serves multiple functions simultaneously: it provides mechanical support for the PT sensor, creates a sealed barrier against refrigerant through the O-ring, and establishes electrical connections via contact terminals. This multi-functionality reduces the number of separate components needed, simplifying the overall manufacturing process while maintaining system integration
3Reliability
If the PT sensor is threadedly fastened to the sensor hole to enhance sealing, then refrigerant leakage is prevented, but assembly and disassembly time increases
Solution Approach 1:
The sensor hole is pre-formed with threaded engagement features directly during valve body manufacturing, eliminating the need for separate threading operations during sensor assembly. The O-ring seal member is pre-installed in the sensor hole before the PT sensor is attached, ensuring proper sealing positioning is achieved automatically during the fastening process, thereby reducing overall assembly time while maintaining reliable sealing
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
Prevents refrigerant leakage, corrosion, and electrical short-circuiting, maintaining consistent refrigerant flow and cooling performance by enhancing the fastening and sealing of the PT sensor within the expansion valve.
Implementation Method 1
a seal member, which prevents the refrigerant from leaking
Implementation Method 2
a thread fastening assembly part configured to threadedly fasten and remove the PT sensor to and from the sensor hole
Implementation Method 3
an electrical connection part configured to constantly electrically connect the sensor circuit board whose position is changed about a thread fastening rotation center axis
Data Source
AI summary
A sensor-integrated expansion valve includes: a PT sensor installed in a sensor hole of a valve body to detect pressure and temperature of refrigerant in a refrigerant flow path, the PT sensor including a sensor body assembled to the valve body portion around the sensor hole, a sensing rod inserted from the sensor body into the sensor hole and having an end portion exposed into the refrigerant flow path, and a sensor circuit board configured to process data on the pressure and the temperature of the refrigerant detected by the sensing rod and transmit the data to a main circuit board of the on the valve body; a thread fastening assembly part configured to threadedly fasten and remove the PT sensor to and from the sensor hole of the valve body; and an electrical connection part configured to constantly electrically connect the sensor circuit board to the main circuit board.