Variable Diameter Drive Wheels for Sewer Cleaning Pump Speed Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sewer cleaning devices face challenges in efficiently managing the flow rate of high-pressure pumps, leading to excessive water usage and potential negative pressure issues when cleaning smaller sewer channels, which can cause odor barriers to fail, resulting in energy wastage and nuisance.

Innovation Solution

The implementation of freely rotatable drive wheels of different diameters connected to a multiple clutch device allows the high-pressure pump to operate at varying speeds while maintaining constant engine speed, ensuring efficient energy use and preventing negative pressure through selective belt tensioning and mechanical torque transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the high-pressure pump is designed to deliver enough flushing water for larger channels, then sufficient flushing capability is achieved for large sewers, but excessive water is used and negative pressure is generated in smaller channels

Engineering Contradiction:
Improveflushing capabilityVSAvoidnegative pressure
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies dynamics by making the drive wheel selection changeable based on operating conditions. Different drive wheel diameters (280mm, 315mm, 355mm) are provided, allowing the transmission ratio between the drive shaft and high-pressure pump to be dynamically adjusted. This enables the system to adapt to different sewer channel sizes, delivering appropriate flushing water flow rates without generating excessive negative pressure in smaller channels.

Inventive Principle:
Principle #15Dynamics

2Quantity of substance

If the motor speed is reduced to decrease the high-pressure pump delivery rate, then water flow is reduced for smaller channels, but the vacuum pump suction capability is also impaired

Engineering Contradiction:
Improvewater flow rateVSAvoidsuction capability
Core Design Contradiction:
Quantity of substanceVSProductivity

Solution Approach 1:

The patent segments the speed control function by providing multiple discrete drive wheel options with different diameters. Each drive wheel corresponds to a specific transmission ratio, allowing independent optimization of the high-pressure pump delivery rate without affecting the vacuum pump. The operator can select the appropriate drive wheel based on channel size requirements, ensuring sufficient water flow for smaller channels while maintaining vacuum pump suction capability.

Inventive Principle:
Principle #1Segmentation

3Speed

If a hydraulic transmission is used to change the high-pressure pump drive speed, then speed adjustment is enabled, but energy losses increase due to poor efficiency

Engineering Contradiction:
Improvepump drive speedVSAvoidenergy losses
Core Design Contradiction:
SpeedVSLoss of energy

Solution Approach 1:

The patent replaces the proposed hydraulic transmission with a mechanical transmission system using drive wheels of different diameters mounted on the drive shaft. This mechanical approach directly transmits power from the drive motor to the high-pressure pump through belt connections, avoiding the energy losses associated with hydraulic transmission. The different drive wheel diameters provide speed variation while maintaining high transmission efficiency.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Quantity of substance

If the delivery flow is divided and fed back into the flushing water tank to limit effective delivery rate, then water flow is reduced for smaller channels, but energy is wasted

Engineering Contradiction:
Improveeffective delivery rateVSAvoidenergy wastage
Core Design Contradiction:
Quantity of substanceVSLoss of energy

Solution Approach 1:

Instead of dividing and recycling water flow, the patent dynamically adjusts the effective delivery rate by selecting different drive wheel diameters. This changes the transmission ratio to directly control the pump's output flow rate at the source, matching the water delivery to the actual channel size requirements without wasting energy on pumping and recycling water that isn't needed.

Inventive Principle:
Principle #15Dynamics

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 solution enables precise control of the high-pressure pump's speed, reducing energy losses and preventing odor nuisance by maintaining efficient operation and minimizing shaft stress, thus ensuring effective and safe sewer cleaning.

Implementation Method 1

a belt transmission, in particular a V-belt transmission

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP2283938B1Device for cleaning sewers
Publication Date: 2013.08.28 WIEDEMANN KARL
  • EP2283938B1 patent drawingFigure 1
  • EP2283938B1 patent drawingFigure 2
  • EP2283938B1 patent drawingFigure 3

AI summary

The device has a clearance hose (13) comprising a runner nozzle (14) at a front end, where the hose is insertable into a canal (1). A drive shaft (23) of a high pressure pump (15) is couplable with an internal drive motor for managing flushing of rinsing water, where the pump is driven at different speeds. Freely rotatable drive wheels (25, 26) of variable diameters and associated with different drive speeds are aligned with the drive shaft. A variable coupling arrangement is selectively couplable with the drive shaft, where the wheels are in a permanent drivable connection with the motor. The internal drive motor comprises vehicle engine.