Nozzle for a vacuum cleaner

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vacuum cleaner nozzles with rotatable brushes driven by air turbines experience uncontrolled increases in rotation speed and noise when lifted off surfaces, causing stress on turbine bearings and excessive noise.

Innovation Solution

A nozzle design with a turbine that is axially displaced relative to the inflow opening via a guide mean, such as a helical groove, adjusts airflow proportion based on load torque, allowing for variable turbine rotation speed and minimizing speed increases when the nozzle is lifted, using a spring and toothed belt mechanism for efficient torque transfer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the nozzle is lifted clear of the surface, then the brush is no longer in contact with the surface, but the rotation speed of the roller brush and air turbine increases uncontrolled causing noise and bearing stress

Engineering Contradiction:
Improvenozzle liftingVSAvoidnoise and bearing stress
Core Design Contradiction:
Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The turbine is made axially movable relative to the inflow opening through a displacing means comprising a projection on a tubular section, a sleeve fixed on the shaft, and a guide mean (helical groove). This dynamic positioning allows the turbine to automatically adjust its position based on load conditions, reducing rotation speed when the nozzle is lifted to minimize noise and bearing stress while maintaining efficient cleaning performance during operation

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The guide mean forms a closed loop path that provides automatic feedback control. The projection moves along the helical groove in response to the difference between drive torque produced by the turbine and load torque applied by the floor cleaning roller, creating a self-regulating system that adjusts turbine position and airflow proportion based on actual loading conditions without external control

Inventive Principle:
Principle #23Feedback

2Productivity

If the turbine rotation speed is increased to maintain cleaning power, then cleaning efficiency improves, but bearing stress and noise increase

Engineering Contradiction:
Improvecleaning efficiencyVSAvoidbearing stress and noise
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The system dynamically adjusts turbine rotation speed based on actual cleaning needs. During cleaning operation, the turbine operates at high speed for efficient cleaning. When the nozzle is lifted, the reduced load torque causes the projection to move along the helical groove, axially displacing the turbine to reduce airflow proportion and rotation speed, thereby minimizing bearing stress and noise while maintaining cleaning capability when needed

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the operational parameters of the turbine by varying its axial position relative to the inflow opening. The displacing means enables the turbine to operate at different speeds and airflow proportions depending on loading conditions, optimizing the balance between cleaning efficiency and harmful effects like bearing stress and noise

Inventive Principle:
Principle #35Parameter changes

3Object-generated harmful factors

If a braking device is used to control rotation speed when lifted, then noise and bearing stress are reduced, but the device complexity increases

Engineering Contradiction:
Improvenoise and bearing stressVSAvoidbraking mechanism
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The invention extracts the speed control function from a separate braking device and integrates it into the turbine's drive mechanism itself. The displacing means with the helical groove guide is incorporated directly into the turbine shaft assembly, eliminating the need for external braking mechanisms while achieving the same noise and bearing stress reduction effects

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The speed control and position adjustment functions are merged into a single integrated displacing means. The projection on the tubular section, the sleeve, and the helical groove work together as one combined mechanism that simultaneously controls turbine axial position and rotation speed, reducing device complexity compared to separate braking and control systems

Inventive Principle:
Principle #5Merging (Combining)

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 solution effectively reduces turbine rotation speed when the nozzle is lifted, minimizing noise and stress on components, while maintaining efficient cleaning performance by adapting to changing surface loads.

Implementation Method 1

A turbine (7) that is rotated by an axis "A2" is placed inside the turbine chamber (3)

Methodology Applied
Scientific EffectAir turbine conversion: Turbine

Implementation Method 2

The displacing means (77) is a spring (76) which is mounted on the shaft (75) that is rotated by the axis "A2"

Methodology Applied
Scientific EffectElastic force: Spring

Implementation Method 3

The transmission means (2) comprises a toothed belt wheel (25) that is mounted on the shaft (75)

Methodology Applied
Scientific EffectMechanical transmission: Gear

Data Source

PatentEP3616582B1Nozzle for a vacuum cleaner
Publication Date: 2021.07.21 BSH HAUSGERATE GMBH
  • EP3616582B1 patent drawingFigure 1~2
  • EP3616582B1 patent drawingFigure 3~4
  • EP3616582B1 patent drawingFigure 5

AI summary

A nozzle (1) for a vacuum cleaner, comprises: a housing (11) having a turbine chamber (3) equipped with an outflow opening (35) which is in communication with a connection tube (6) connecting the turbine chamber (3) to a suction unit of the vacuum cleaner and an inflow opening (34) which is in communication with a suction opening (12) of the housing (11), a turbine (7) that is rotated by an axis "A2", is placed inside the turbine chamber (3) and being movable connected with a shaft (75) by a displacing means (77) used for axially displacing the turbine (7) with respect to the inflow opening (34) along the shaft (75), a floor cleaning roller (4) mounted in the housing (11) close to the suction opening (12) and rotatable relative to the housing (11) about an axis of rotation "A1", a transmissions means (2) transferring a drive torque "T" produced by the turbine (7) to the floor cleaning roller (4), wherein the displacing means (77) comprises at least one projection (78) provided on inside wall of a tubular section (781) of the turbine (7), a sleeve (79) spaced radially inwardly apart the tubular section (781) on the shaft (75) provided with a guide mean (791) which receives projection (78) and therefore engages the turbine (7) with the sleeve (79) and the guide mean (791) is formed as a closed loop path (92) at least partially shaped as a helical groove (92'), along which the projection (78) is moved accordingly to a difference between the drive torque "T" produced by the turbine (7) and a load torque "L" applied on the shaft (75) by power uptake of the floor cleaning roller (4) through the transmission means (2), therefore an axial displacing (D) of the turbine (7) with respect to the inflow opening (34) is ensured. Thus, a reciprocating movement of the turbine along the shaft with respect to the inflow opening is provided by the projection which slides along the guide mean, that is formed as the closed loop path, what results that the projection is moved from a starting point i.e. when the turbine is not displaced, to the extreme point i.e. when the turbine experiences the maximum axial displacing "D" via longer path than when it returns from the extreme point to the starting, thereby the projection faster achieves the starting point on the sleeve when the load torque "L" falls down.