Compact Dose Indicator Using Angled Worm Drive
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Solution Overview
Problem
Existing metered dose inhalers lack a reliable method to determine the remaining medicament dosage, leading to potential misuse due to unknown contents, as existing dose counters are either too large or not robust enough to fit within the inhaler's design.
Innovation Solution
A dose counter with an indicator member rotatable at an obtuse angle, driven by a worm mechanism, allowing for compact and robust design capable of counting 200-plus doses, integrated within the inhaler's actuator to maintain form and size consistency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a dose counter is mounted within the interior of the actuator beneath the aerosol container, then the inhaler form and size remain unchanged, but the dose counter becomes too large to fit in the available space when requiring 200-plus counts
Solution Approach 1:
The patent reorients the indicator member's rotation axis from a conventional horizontal position to an angled position (e.g., 45 degrees) relative to the actuation axis. This dimensional reorientation allows the indicator member to rotate within a different spatial plane, effectively utilizing three-dimensional space more efficiently and reducing the counter's footprint in the constrained actuator volume while maintaining full counting capability.
Solution Approach 2:
The dose counter components are nested within the existing actuator structure. The indicator member is positioned within the actuator housing, and the counting mechanism is integrated into the available space beneath the aerosol container. This nesting approach allows the dose counter to occupy minimal space while functioning within the existing inhaler form factor.
2Ease of operation
If the indicator member is positioned to provide readable indicia for the user, then usability is improved, but the dose counter requires more space than available in the actuator
Solution Approach 1:
By angling the indicator member's rotation axis, the patent creates a compact rotational path that fits within the actuator's depth while positioning the dose indicia in a location accessible to the user. The angled orientation allows the indicator to sweep through a readable arc without requiring excessive lateral or vertical space.
Solution Approach 2:
The patent positions the readable indicia of the indicator member at a specific location and orientation that is optimally visible to the user during normal inhaler handling. The indicator member's design concentrates the information display function in a small, strategically positioned area rather than requiring a large display surface.
3Reliability
If the dose counter is made robust for reliable operation, then reliability is improved, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The dose counter is designed as a modular assembly of discrete components including the indicator member, counting mechanism, and housing elements. This segmentation allows each component to be manufactured separately using standard processes and then assembled, reducing overall manufacturing complexity while maintaining reliability through proven individual component designs.
Solution Approach 2:
The indicator member serves multiple functions: it acts as the counting element, the display element, and the mechanical linkage between the actuation mechanism and the dose indication system. This multi-functionality reduces the total number of parts required, simplifying manufacturing while ensuring reliable operation through fewer potential failure points.
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 users to accurately track medicament usage without altering the inhaler's size or form, ensuring reliability and robustness while minimizing space usage, thus preventing misuse due to empty containers.
Implementation Method 1
the dose counter further comprises a worm rotatable about a worm axis, wherein said worm comprises a worm shaft and a worm thread and is arranged to drive said indicator member
Data Source
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AI summary
A dose counter is described. The dose counter may be used, for instance, in a medical inhaler device.