Sliding and lifting mechanism of a shelf of an item of furniture or household device, item of furniture and household device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sliding and lifting mechanisms for shelves in household appliances, such as dishwashers, often require high side walls for locking, which are not available in free-standing configurations, making it difficult for users to easily lift and lock the shelf in an upper position, especially when the load on the dish rack is high.
Innovation Solution
A sliding and lifting mechanism featuring a knee joint coupled to a scissor mechanism, with a pivoting lever and toggle lever that allows the shelf to be locked in an overstretched position without needing high side walls, and an energy storage mechanism like a tension spring to assist in lifting and maintain the locked position, along with rollers on scissor levers for combined sliding and lifting movements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a scissor mechanism with high side walls is used for locking, then the shelf can be locked in the upper position, but the device becomes more complex and is not suitable for free-standing configurations
Solution Approach 1:
The invention extracts the locking function from the high side walls and implements it through a knee joint mechanism integrated into the scissor mechanism. The knee joint (formed by pivoting lever and toggle lever) provides the locking function without requiring external high side walls, thus simplifying the overall structure while maintaining reliability.
Solution Approach 2:
The locking mechanism is merged with the scissor mechanism itself. The knee joint is formed by components (pivoting lever and toggle lever) that are already part of the scissor mechanism, combining the lifting and locking functions into a single integrated system rather than separate components.
2Reliability
If the shelf is lifted by a handle against high load, then the shelf can be raised to the upper position, but the ease of operation deteriorates
Solution Approach 1:
The energy store (spring) acts as a counterweight mechanism, storing potential energy when the shelf is lowered and releasing it during lifting. This counteracts the gravitational force on the shelf, significantly reducing the user effort required to lift the shelf to the upper position while maintaining the ability to lift high loads.
Solution Approach 2:
The mechanism transitions from a static lifting system to a dynamic one with energy storage. The spring provides dynamic assistance during the lifting process, adapting the force requirements throughout the motion range and making operation easier while maintaining lifting capability.
3Reliability
If blocking levers are used to lock the scissor mechanism, then the shelf can be locked in the upper position, but the ease of operation worsens due to complex operation while raised
Solution Approach 1:
The knee joint mechanism is designed to lock automatically when the shelf reaches the upper position through the scissor mechanism's motion. The toggle lever and pivoting lever naturally form the locked position (overstretched knee joint) as part of the lifting motion, eliminating the need for separate manual locking operations by the user.
4Ease of operation
If an energy store is coupled to the scissor mechanism, then the lifting force is improved, but the device complexity increases
Solution Approach 1:
The energy store is integrated into the existing scissor mechanism structure. The spring is coupled to the scissor levers and knee joint components that are already present, merging the energy storage function with the structural components rather than adding completely separate elements.
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
Enables easy lifting and locking of the shelf in an upper position with reduced user effort, ensuring the shelf remains locked securely without the need for high side walls, and provides uniform force during lifting, minimizing the risk of unintentional unlocking.
Implementation Method 1
an energy storage mechanism like a tension spring to assist in lifting and maintain the locked position
Data Source
Figure 1a
Figure 1b
Figure 1c
AI summary
The invention relates to a sliding and lifting mechanism of a shelf (5) of an item of furniture or household device (1) having a scissor-type mechanism (53-55) for pulling the shelf (5) out of a body (2) of the item of furniture or household device (1) and for lifting the shelf (5), characterised in that the sliding and lifting mechanism has a knee joint (59) that is coupled to the scissor-type mechanism (53-55) and locks the shelf (5) in a lifted position. The invention also relates to an item of furniture or a household device (1) having a sliding and lifting mechanism of this type.