Nestable Shopping Trolley Shelf Locking Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shopping carts with sliding shelves experience annoying rattling and potential corrosion due to the shelf resting on the chassis in the non-use position, which also increases susceptibility to damage.
Innovation Solution
A locking mechanism that allows the shelf to maintain stable balance without additional supports on the chassis, using a form-fitting slider or roller that falls into a V-shaped recess, and a guide formed by a rail or curved rod, ensuring the shelf does not touch the chassis in the non-use position, and can be easily pulled out for stacking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the shelf rests on the chassis in the non-use position, then the shelf is supported and stable, but rattling occurs and corrosion damage increases at the contact point
Solution Approach 1:
A locking mechanism acts as an intermediary between the shelf and chassis, providing stable support through positive-locking engagement of a slider/roller with a V-shaped recess, rather than direct resting contact. This mediator eliminates rattling and corrosion by creating a controlled, form-fitting connection point.
Solution Approach 2:
The patent replaces the simple mechanical resting contact system with a more sophisticated locking mechanism system that includes guides, sliders/rollers, and V-shaped recesses. This substitution transforms the support method from passive resting to active locking, eliminating harmful rattling and corrosion effects.
2Stability of the object's composition
If additional supports are added on the chassis for the shelf elements, then the shelf stability improves, but the device complexity increases
Solution Approach 1:
The locking mechanism serves multiple functions simultaneously: it provides stable support for the shelf, prevents rattling, eliminates corrosion, and enables easy stacking. By integrating these functions into a single mechanism rather than adding separate supports for each function, the patent avoids increasing overall device complexity.
Solution Approach 2:
The patent combines the support function, stability function, and anti-rattling function into a single integrated locking mechanism system. The guides, sliders/rollers, and V-shaped recesses work together as one unified system, replacing what would otherwise require multiple separate support components.
3Device complexity
If the shelf is locked in position without additional supports, then the device complexity decreases, but the shelf may become unstable
Solution Approach 1:
The locking mechanism acts as an intermediary that provides stable locked positioning without requiring additional support structures. The form-fitting engagement between the slider/roller and V-shaped recess creates inherent stability through geometric constraint, eliminating the need for extra supports while maintaining shelf stability.
4Ease of operation
If the shelf can be easily pulled out for stacking, then the ease of operation improves, but the locking mechanism complexity increases
Solution Approach 1:
The locking mechanism transitions between two dynamic states: locked position for stable operation and unlocked position for easy stacking. The design allows simple manual manipulation to switch between these states, providing ease of operation. The dynamic nature of the system enables it to adapt between stability and mobility as needed.
Solution Approach 2:
The V-shaped recess and slider/roller design allows the shelf to be easily pulled out by hand for stacking without requiring tools or complex release mechanisms. The geometric form of the locking elements enables self-service operation where the user can directly manipulate the shelf to engage or disengage the lock.
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 prevents rattling and corrosion by maintaining the shelf's stability without additional chassis contact, allowing for efficient stacking and preventing improper positioning that could damage the shelf or impair its function.
Implementation Method 1
the locking mechanism keeps the shelf in stable equilibrium when not in use
Implementation Method 2
a slider (or a roller) on the front section of the shelf, which falls into a recess when not in use
Implementation Method 3
The guide is formed by a rail with the V-shaped recess integrated therein
Data Source
Figure 1~3
Figure 2a
Figure 2b
AI summary
The present invention relates to a stackable shopping cart (1) with a sliding device (9) and a chassis (2) equipped with casters (3), the longitudinal sides (4) of which are formed by one- or multi-part supports (12) which support a basket (6) tapering in the sliding direction, the rear end of which can be closed by a flap (8), wherein a shelf (25) for storing larger items is provided in the rear area (5) of the shopping cart (1), which can be moved from a non-use position to a rear use position and vice versa, and which has a pivoting part (26) and a storage part (30).wherein the pivoting part (26) is pivotably mounted on the chassis (2) about a horizontal axis (29) and wherein the parking part (30) with its front section (32) rests on a guide (12') on the supports (12) in a sliding manner and with its rear section (31) is pivotably connected to the pivoting part (26) about a horizontal axis (33), wherein the parking part (30) with its front section (32) is releasably locked against horizontal displacement in the non-use position.