Self-cleaning Pump Recessed Notch Shearing Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Centrifugal pumps face inefficiencies and clogging issues due to entrained solid debris, particularly in sewage applications, where designs struggle to maintain high efficiency while preventing jamming and leakage.
Innovation Solution
A self-cleaning centrifugal pump design featuring recessed notches and ramps on both the impeller and volute, which create a shearing action to expel debris, ensuring reliable operation and high efficiency by allowing close proximity between the impeller and volute without clogging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the impeller is positioned in very close proximity to the volute case to maintain pumping efficiency, then pumping efficiency is improved, but the risk of clogging and jamming by solid debris increases
Solution Approach 1:
The pump system performs self-cleaning through the interaction between the rotating impeller and stationary volute notches. The shearing action automatically expels debris without external intervention, allowing the system to maintain both high efficiency and reliability autonomously
Solution Approach 2:
Debris is extracted from the problematic zone between the impeller and volute through the shearing action of the notches. The notches actively remove particles that would otherwise cause clogging, enabling close proximity operation
2Productivity
If physical seals and minimal running clearances are used between impeller and volute, then pumping efficiency is improved, but the pump becomes prone to debris interference at seals and narrow clearances
Solution Approach 1:
Debris is extracted from the clearance zone before it can interfere with seals or cause jamming. The notches continuously remove particles through shearing action, protecting the sealing interfaces from debris contamination
Solution Approach 2:
The notches act as intermediary elements between the impeller and volute surfaces. They mediate the interaction by providing a mechanism to expel debris, preventing direct contact between contaminants and critical sealing surfaces
3Productivity
If a closed impeller design is used to eliminate slip and improve efficiency, then pumping efficiency is improved, but a seal must be created between impeller and volute which limits leakage but also traps debris
Solution Approach 1:
The closed impeller system performs self-cleaning through the shearing action of the notches. Debris that becomes trapped is automatically expelled through the interaction between rotating and stationary notches, maintaining both sealing effectiveness and debris rejection
Solution Approach 2:
Debris is extracted from the sealed clearance zone through the shearing action of the notches. The rotational movement creates a self-cleaning mechanism that removes contaminants without compromising the seal
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 design effectively cuts and discharges debris, maintaining high pumping efficiency and preventing jamming, even with unpredictable types of contaminants, ensuring reliable operation and reduced heat generation.
Implementation Method 1
features are provided in the volute and impeller such that one essentially scrapes the other and expels debris by forcing along a ramp
Implementation Method 2
A typical centrifugal pump is comprised of a rotating body known as an impeller, which rotates within a stationary volume called a volute
Data Source
AI summary
A pump comprising a volute housing, a rotatable shaft, and an impeller. The volute housing comprises a volute cavity side wall, an upper cylindrical wall, and an upper wall. The upper cylindrical wall extends upwardly from an upper perimeter edge and includes an upper recessed notch formed therein. The upper wall extends radially inwardly from the upper cylindrical wall. The rotatable impeller is operatively coupled to the rotatable shaft and comprises a top cylindrical wall and a top flange. The top cylindrical wall extends upwardly from a top perimeter edge of the top flange and includes a top recessed notch formed therein. The top cylindrical wall is separated from the upper cylindrical wall of the volute housing by an upper annular gap. The top recessed notch of the rotatable impeller and the upper recessed notch of the volute housing may be slot-shaped or wedge-shaped.