Eccentric Screw Pump Stator Radial Adjustment via Inclined Shims
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing uniaxial eccentric screw pumps face challenges in uniformly compressing the stator toward the inner diameter side, leading to variations in the clamping state and potential pulsation during fluid conveyance. Additionally, these pumps often have complex shapes and high processing costs, making adjustment and uniform clamping difficult.
Innovation Solution
The proposed solution involves a uniaxial eccentric screw pump configuration that includes a stator with a female screw through hole, a male screw rotor, and a plurality of shims with inclined surfaces. These shims are arranged along the stator's length and are compressed radially inward by an adjustment member with guide parts, allowing for uniform pressing of the stator.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the stator casing is pressed by the tension member at positions protruding from both end parts, then the clamping force is applied, but the stator casing cannot uniformly press the entire stator in the longitudinal direction, causing variations in clamping state and pulsation
Solution Approach 1:
The patent divides the clamping function into multiple segments by placing pressing rings at both end parts of the stator and a central pressing ring at the middle position. This segmentation allows each pressing ring to independently apply clamping force to its respective region, ensuring uniform compression along the entire longitudinal direction of the stator, thereby eliminating variations in clamping state and preventing pulsation during operation
Solution Approach 2:
The pressing rings are pre-installed at specific positions (both ends and center) of the stator before operation. These pressing rings are equipped with adjustment mechanisms that allow the clamping force to be preliminarily adjusted to the appropriate level, ensuring that the stator is uniformly compressed from the outset, which prevents pulsation and maintains stable operation throughout the pump's service life
2Force
If multiple adjustment bolts press the pump body at multiple locations via plate members, then the clamping force is distributed, but the shape becomes complicated and processing becomes difficult and expensive
Solution Approach 1:
The pressing rings serve multiple functions: they apply clamping force to the stator, provide adjustment mechanisms for force control, and act as structural components that simplify the overall design. By integrating these functions into single components rather than using separate adjustment bolts and plate members, the patent reduces the number of parts, simplifies the structure, and makes the pump easier and less expensive to manufacture while still achieving distributed clamping force
3Productivity
If the stator is made longer to increase pumping capacity, then the fluid conveyance volume increases, but variations in clamping state and pulsation become more conspicuous
Solution Approach 1:
For longer stators, the patent divides the clamping system into multiple segments by placing pressing rings at both end parts and a central pressing ring at the middle position. This segmentation ensures that each section of the long stator receives uniform clamping force independently, preventing variations in clamping state that would otherwise become more pronounced with increased length, thereby maintaining stable operation and reducing pulsation even in high-capacity applications
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
This configuration allows for a simple and cost-effective adjustment of the clamping state, ensuring uniform compression of the stator and stable fluid conveyance without pulsation. The use of shims and an adjustment member facilitates easy adjustment and maintenance, reducing processing costs and complexity.
Implementation Method 1
a plurality of shims (9) which are arranged on a radially outside of the stator (8) in a range from one end to an other end of the stator (8), are in surface contact with an outer surface of the stator (8), and are capable of compressing the stator (8) by moving radially inward with respect to the stator (8)
Implementation Method 2
have, on an outer surface, an inclined surface gradually inclined radially inward or outward toward one end; and an adjustment member (10) that is movable in an axial direction with respect to the stator (8) and has a pressing part that can press the inclined surface of each of the shims (9)
Data Source
AI summary
A uniaxial eccentric screw pump includes: a stator having a through hole 8a whose inner surface is formed in a female screw shape; a rotor that is a male screw shaft body inserted into the through hole of the stator; a plurality of shims that are arranged on a radially outside of the stator in a range from one end to the other end of the stator, are in surface contact with an outer surface of the stator, are capable of compressing the stator by moving radially inward with respect to the stator, and have, on an outer surface, an inclined surface gradually inclined radially inward or outward toward one end; and an adjustment member that is movable in an axial direction with respect to the stator and has a pressing part that can press the inclined surface of each of the shims.