Cushion for seating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wheelchair seat cushions fail to effectively eliminate pressure concentrations at the transition zones between different materials, leading to discomfort and increased risk of pressure ulcers due to differences in physical properties between the cushion base and bladder or fluid membrane systems.
Innovation Solution
A hybrid seating cushion design featuring a cushion base with a void and a bladder positioned within, where the bladder's outer wall extends under the lip edge of the cushion base, reducing the transition area by allowing the cushion base to fill the gap between the bladder and the seating surface, thus minimizing pressure concentrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fluid membrane sack or air-cell bladder is used to support the buttocks under evenly distributed pressure, then pressure redistribution at bony prominences is achieved, but a transition zone forms at the region where the bladder/sack and foam base converge, creating uncomfortable pressure differences
Solution Approach 1:
The patent removes the transition zone by extracting the bladder/sack from the traditional configuration where it contacts the user directly at the interface with the foam base. Instead, the bladder is positioned entirely within a void in the foam base, eliminating the harmful transition area where pressure concentrations occur.
Solution Approach 2:
The bladder is nested within a void in the foam base, with the foam material surrounding the bladder. This nesting configuration allows the foam to fill the transition zone between the bladder and the user's body, eliminating pressure concentrations while maintaining the pressure redistribution benefits of the bladder.
2Adaptability or versatility
If two different materials (bladder/sack and foam base) are used in a cushion, then pressure redistribution and support are provided, but the physical properties of these materials are significantly different in the transition areas, reducing cushion performance and comfort
Solution Approach 1:
The patent applies different materials in specific locations: the bladder provides pressure redistribution in the contact area with the user's buttocks, while the foam base provides structural support and fills the transition zone. Each material is positioned where its specific properties are most beneficial, eliminating the harmful effects of material interfaces.
Solution Approach 2:
The foam base acts as an intermediary between the bladder and the user's body. It fills the void around the bladder and provides a smooth transition surface that eliminates pressure concentrations, mediating between the fluid/air bladder and the user's skin.
3Area of stationary object
If the bladder outer wall is positioned at the seating surface level, then the transition area is minimized, but the difference in physical properties between cushion base and cushion insert still produces uncomfortable pressure differences
Solution Approach 1:
The patent extracts the bladder from direct contact with the user's body at the interface zone. The bladder is positioned entirely within the void in the foam base, removing it from the area where pressure differences between materials would cause discomfort.
Solution Approach 2:
The solution moves the problem to another dimension by positioning the bladder vertically within the foam base rather than horizontally at the surface. The bladder occupies the vertical space in the void, allowing the foam to surround it and eliminate interface problems at the user contact surface.
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 design provides a more comfortable seating experience by reducing the transition area, eliminating pressure concentrations, and enhancing support for bony prominences, thereby reducing the risk of pressure ulcers.
Implementation Method 1
The bladder may be configured to support an ischial tuberosity, a coccyx, and/or a sacral area of the user
Implementation Method 2
When a user is seated on the seating surface, the bladder may be configured to support an ischial tuberosity, a coccyx, and/or a sacral area of the user
Data Source
AI summary
A hybrid seating cushion made up of a cushion base and a cushion insert. The cushion base has a seating surface in which a void in or extending through the cushion base is formed. A cushion insert such as an air bladder or fluid sack is positioned within the void. A lip or upper surface around an opening in the void overhangs at least a portion of the cushion insert, thereby minimizing the size and corresponding negative effects of a transition area where the base and the insert overlap.