Deformable Element Pump Axial Calibration for Pressure Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pumps for delivering liquid additives in exhaust-gas purification systems are not cost-effective, reliable, and prone to pressure fluctuations, which can damage the system and affect the spray pattern, and they fail to operate effectively at low temperatures where the additives can freeze.
Innovation Solution
A pump design featuring a rotatable eccentric and a deformable element that forms a sealed delivery path, with an adjustable axial calibration device to ensure precise dosing and minimize pressure fluctuations, using a deformable diaphragm or hose to maintain fluid-tight seals and prevent backflow, and an external rotor configuration to reduce friction and enhance durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a conventional pump design is used for delivering liquid additives, then the pump structure is simple, but the pump generates pressure fluctuations that adversely affect the spray pattern and can damage the system
Solution Approach 1:
The patent employs a deformable element (diaphragm or hose) that dynamically changes shape during operation to maintain fluid-tight seals and minimize pressure fluctuations. The deformable element is pinched by the eccentric to create seals that adapt to pressure changes, ensuring stable delivery without damaging pressure spikes while maintaining a relatively simple pump structure.
2Ease of manufacture
If a conventional pump design is used for delivering liquid additives, then the manufacturing cost is low, but the pump lacks reliable dosing function and produces excessive noise
Solution Approach 1:
The pump delivers liquid in segmented, discrete portions through the action of the eccentric pinching the deformable element at specific points in the rotation cycle. This segmentation of the flow into controlled portions enables accurate dosing function while maintaining the simplicity and low manufacturing cost of the overall pump design.
3Device complexity
If a conventional pump design is used, then the pump structure is simple, but the pump is damaged when liquid additive freezes at low temperatures
Solution Approach 1:
The patent uses a deformable element (flexible diaphragm or hose) as a key component that can expand when liquid additive freezes inside it. This flexible shell absorbs the expansion pressure without damaging the rigid pump structure, enabling the pump to withstand freezing conditions while maintaining a relatively simple overall design.
4Measurement precision
If the deformable element is tightly sealed to prevent backflow, then the dosing precision is improved, but the pump generates higher pressure fluctuations
Solution Approach 1:
The deformable element creates dynamic seals that are tight enough to prevent backflow and ensure dosing precision, but flexible enough to absorb pressure variations. The eccentric pinches the deformable element in a controlled manner that maintains seal integrity while minimizing pressure spikes, achieving both precise dosing and stable pressure delivery.
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 pump achieves accurate and reliable delivery of liquid additives with minimal pressure fluctuations, operates effectively at low temperatures, and maintains system integrity by preventing freezing and backflow, ensuring precise dosing and efficient operation.
Implementation Method 1
the deformable element is pinched or compressed between the housing and the eccentric, such that, in the region of the seal, the gap is completely closed by the deformable element
Implementation Method 2
the at least one displaceable seal separates off at least one closed pump volume in the delivery path. By a movement of the eccentric, the at least one displaceable seal can be displaced in a delivery direction from the inlet to the outlet for the purposes of delivering the liquid along the delivery path
Data Source
AI summary
A pump for pumping a liquid has a pump housing with at least one inlet and at least one outlet. The pump housing has an eccentric rotatable relative to the pump housing by an axle. A deformable element is arranged between the pump housing and the eccentric, and by the deformable element, at least one pump path from the at least one inlet to the at least one outlet is delimited and at least one movable pump path seal is formed, which separates at least one closed pump volume in the pump path. The at least one movable seal is movable in a pump direction from the inlet to the outlet by a movement of the eccentric to pump the fluid along the pump path. The pump has at least one adjustable axial calibrating device, by which the deformable element is clamped in the axial direction parallel to the axle.