Breather Pipe Connection State Determination via Pulsation Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional connection state determination devices for breather pipes in internal combustion engines with superchargers are limited in precision and operational range, often only determining the connection state when intake quantity reaches a threshold and during a narrow range of engine operation states, leading to insufficient accuracy.
Innovation Solution
A connection state determination device that uses a pipe internal pressure sensor to detect pulsation waveforms within the breather pipe, determining the connection state based on the amplitude of these waveforms across a wide range of engine operation states, from low to high load, by employing Fourier series analysis and threshold comparisons to assess the breather pipe's air-tightness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the conventional determination device uses integration value comparison of crank case vent tube pressure, then the connection state can be determined, but the determination precision is insufficient and the operational range is narrow
Solution Approach 1:
The invention changes the detection parameter from integration value of pressure to amplitude of pulsation waveform. By detecting the amplitude of pressure pulsations in the breather pipe and comparing it to threshold values, the system achieves high-precision connection state determination across a wide operational range including both low-load and high-load conditions
Solution Approach 2:
The invention utilizes the natural pulsation (vibration) of pressure in the breather pipe system caused by engine operation. By detecting and analyzing the amplitude of these pressure pulsations, the system can determine connection state without being constrained by specific operational conditions, thereby expanding the operational range while maintaining high precision
2Reliability
If the determination is performed based on integration value during predetermined period, then the connection state can be assessed, but the determination cannot be performed when execution condition is not satisfied at start-up
Solution Approach 1:
The invention performs preliminary detection of pulsation waveform amplitude from the beginning of engine operation. By continuously monitoring the amplitude of pressure pulsations and comparing against thresholds, the system can determine connection state immediately at start-up without waiting for specific execution conditions to be satisfied, thereby improving both reliability and ease of operation
3Productivity
If the conventional device determines connection state only when intake quantity reaches threshold, then determination can be performed, but it is limited to relatively narrow range of operation state
Solution Approach 1:
The invention enables continuous determination of connection state by continuously detecting the amplitude of pulsation waveforms throughout all engine operations. Unlike conventional methods that wait for specific conditions, this system continuously monitors pressure pulsation amplitude and performs determination whenever the engine is running, achieving both high productivity and wide operation state coverage
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
Enables precise determination of the breather pipe's connection state under various operational conditions, improving accuracy and ensuring proper connection assessment in both low and high load regions, thereby enhancing the reliability of the engine's ventilation system.
Implementation Method 1
a pipe internal pressure sensor that detects pressure inside the breather pipe
Implementation Method 2
a pulsation waveform obtaining part for obtaining pulsation due to variation of pressure inside the breather pipe as a pulsation waveform based on the detected pressure
Data Source
AI summary
Provided is a connection state determination device. The connection state determination device for the breather pipe determines the connection state of a breather pipe in an internal combustion engine having a supercharger, and the breather pipe is connected between an engine body including a crank case and an intake passage on the upstream side of a compressor of the supercharger, and communicates the crank case and the intake passage. The connection state determination device includes a pipe internal pressure sensor that detects the pressure inside the breather pipe, a pulsation waveform obtaining part for obtaining pulsation due to the variation of pressure inside the breather pipe as a pulsation waveform based on the detected pressure, and a connection state determination part that determines the connection state of the breather pipe based on the pulsation waveform.