Sensor Structure for Intake Air Pressure Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sensor structures for measuring intake air pressure in internal combustion engines face challenges in maintaining sensitivity and preventing contamination when the pressure intake port is in contact with the side wall of the insertion hole, due to dimensional inaccuracies in air cleaner components and the presence of contaminants like water droplets and fine air suspended substances.
Innovation Solution
A sensor structure with an enlarged pressure intake port on the side face of the housing structural component, which reduces dynamic pressure effects and positions the intake port to avoid direct exposure to airflow, and includes partition walls and communication grooves to prevent contamination, ensuring stable pressure measurement even with low dimensional accuracy and potential contact with the side wall.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the pressure intake port is disposed on the side face of the housing structural component, then the dynamic pressure effect caused by airflow is avoided, but the opening portion of the pressure intake port may be brought into contact with the side wall of the insertion hole on the sensor, reducing measurement sensitivity
Solution Approach 1:
The pressure intake port is divided into two distinct portions: a first portion (opening portion) and a second portion (communication passage). This segmentation allows the opening to be positioned away from the side wall contact area while maintaining communication with the interior space, thus preserving measurement sensitivity even when contacted by the side wall.
Solution Approach 2:
The first portion of the pressure intake port acts as an intermediary between the external atmosphere and the second portion (communication passage). This intermediary structure allows the opening to be exposed to atmospheric pressure while isolating the sensitive measurement area from direct contact with the side wall, maintaining measurement accuracy.
2Reliability
If the pressure intake port is opened inside or in the middle of an insertion hole on the sensor, then the dynamic pressure effect caused by airflow is avoided, but the molding dimensional precision of the air cleaner is not so high, causing the positional relationship between the mounting position of the sensor and the position of the insertion hole to be easily varied
Solution Approach 1:
The pressure intake port is segmented into a first portion that can be positioned independently within the insertion hole. This allows the opening portion to be located optimally for avoiding dynamic pressure effects while the second portion maintains communication with the interior space, compensating for dimensional variations in the air cleaner housing.
3Object-affected harmful factors
If a filter capable of filtering fine carbon contained in exhaust gas is used, then contaminated substances and water droplets are prevented from entering the engine, but a large pressure loss is caused, reducing engine output and fuel efficiency
Solution Approach 1:
The pressure intake port extracts a small amount of atmospheric pressure for measurement purposes, separate from the main airflow path through the air filter. This allows pressure measurement without requiring the entire airflow system to use a high-performance filter, thus avoiding the pressure loss associated with fine particle filtration while still protecting the pressure measurement device.
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
The sensor structure effectively stabilizes pressure measurement by minimizing dynamic pressure effects and preventing contaminants from reaching the pressure measurement device, maintaining sensitivity and reducing pressure loss, thus enhancing engine performance and fuel efficiency.
Implementation Method 1
a pressure measurement device mounted in a housing structural component of the mass airflow measurement device for measuring the pressure inside the intake air tube
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A sensor structure is provided so that a dynamic pressure effect caused by airflow is avoided as much as possible even when a mass airflow measurement device 16 is integrated with a pressure measurement device 3, thereby preventing contaminated substances, water droplets, or the like from arriving at a pressure measurement part. In the sensor structure, the mass airflow measurement device 16 is inserted into a sensor insertion port 4 provided in an intake air tube component including an intake air tube and is fixed to the intake air tube, and a pressure measurement device 3 is mounted in a housing structural component of the mass airflow measurement device 16 for measuring the pressure. The pressure measurement device 3 and the inside of the intake air tube are connected by a pressure intake port 11 provided in the housing structural component. An opening portion of the pressure intake port 11 is provided on a side face of the housing structural component, and the cross-sectional area of the opening portion is larger than the cross-sectional area of the pressure intake port.