> ## Content Index > Fetch the complete content index at: https://www.kevos.com/llms.txt > Use this file to discover other available public pages before exploring further. # Currency Sanitiser Machine – Special-Purpose Machine and Product Development | Wink Solutions - URL: https://www.kevos.com/currency-sanitiser-machine-design-support/ - Published: 2021-09-25T14:00:00.000Z - Updated: 2026-09-29T07:51:28.000Z - Description: Special-Purpose Machine Design | Product Development | Mechanical Engineering | DFM | Prototyping - Author: K G J - Tags: KEVOS® Mechanical Project, KEVOS® Projects, KEVOS® Medical Projects **Client:** Wink Solutions **Project Period:** 2021 **Project Stage:** Mechanical design, CAD development and product-development support This project involved supporting the development of a specialised machine intended to process and sanitise both paper banknotes and coins within a compact public-facing device. The project originated during the COVID-19 period, when businesses were exploring methods of reducing physical contact and improving hygiene around frequently handled items. The engineering challenge was unusual because two very different types of currency needed to be processed within the same product. Banknotes required controlled, low-force handling to avoid damage, while coins required a mechanically robust handling arrangement capable of accommodating their weight, geometry and repeated movement. My contribution focused on mechanical design, CAD development and design-for-manufacture refinement, helping translate the initial product concept into a structured mechanical system suitable for further prototyping and manufacturing development. ## Project Context The proposed machine needed to perform several functions within a relatively compact enclosure. The design had to consider: - Banknote handling - Coin handling - Sanitisation processes - Mechanical reliability - User interaction - Product size - Internal component packaging - Serviceability - Manufacturability - Assembly - Supply-chain availability - Potential higher-volume production The central engineering problem was that notes and coins could not be handled using the same mechanical arrangement. The product therefore required two different processing paths within one coordinated machine architecture. ## Engineering Requirements Development began by understanding how each type of currency behaved mechanically. Paper currency is lightweight, flexible and easily damaged. Coins are significantly heavier, rigid and capable of generating impact and wear within mechanical systems. These differences influenced nearly every part of the machine design. The engineering requirements therefore needed to consider: ### Banknote Path The note-handling mechanism needed to: - Guide notes consistently - Avoid tearing or excessive deformation - Maintain controlled contact - Minimise jamming - Provide sufficient exposure through the sanitisation area - Allow practical user loading and collection ### Coin Path The coin-handling system needed to: - Accommodate different coin sizes - Withstand repeated impacts - Provide consistent movement - Support the selected sanitisation process - Minimise trapping and jamming - Remain accessible for service and cleaning Treating the two media separately allowed the design to be developed around their actual physical behaviour rather than forcing one mechanism to perform incompatible functions. ## Dual-Path Machine Architecture A dual-path mechanical arrangement formed the basis of the design. The banknote section used a controlled roller-based feed concept. The objective was to move notes through the sanitisation area while maintaining sufficient control over their position and minimising the potential for damage. The coin section used a more robust tumbling and movement concept suitable for metallic currency. Both systems then needed to be packaged within one enclosure. This created an additional systems-engineering challenge because the two mechanisms competed for: - Space - Drive components - Electrical interfaces - Access - Service areas - Structural support - User-interface positioning The project therefore required thinking about the machine as a complete system rather than designing the mechanisms independently. ## Banknote Feed Development The note path required particular attention to roller geometry and contact. Too little control could allow notes to skew or jam. Too much pressure could crease or damage them. The design therefore involved refining relationships between: - Roller position - Feed geometry - Clearances - Note guides - Contact pressure - Entry and exit paths This type of mechanism development requires careful attention to tolerance because relatively small dimensional changes can significantly influence feeding performance. Iterative CAD development and prototype feedback were therefore important parts of refining the mechanism. ## Coin Handling Mechanism The coin path required a different approach. Coins can tolerate greater mechanical forces, but they introduce different problems including impact, noise, wear and the possibility of multiple coins interacting within the mechanism. The concept incorporated a tumbling-style arrangement to move coins through the sanitisation process. Mechanical development needed to consider: - Coin movement - Internal geometry - Material durability - Component clearances - Potential wear - Access for clearing obstructions - Cleaning - Integration with the wider enclosure The result was a mechanically separate subsystem designed around the characteristics of metallic currency. ## 3D CAD Development Autodesk Inventor was used to develop the mechanical architecture and individual components. Three-dimensional modelling allowed the internal machine arrangement to be developed and evaluated before committing to further prototype iterations. The CAD environment supported consideration of: - Mechanism geometry - Component clearances - Internal packaging - Assembly relationships - Enclosure constraints - Fastener access - User interaction - Maintenance access - Manufacturing feasibility This was particularly important because compact equipment requires multiple systems to occupy a limited physical volume without interfering with one another. ## Iterative Product Development The design developed through multiple iterations. Early concepts provided a starting point, but mechanical systems often reveal additional requirements during prototyping and review. Dimensions, tolerances and component arrangements were progressively refined as the behaviour of the system became better understood. This iterative process can be represented as: **Concept → CAD → Prototype → Review → Modify → Re-test** The objective was not simply to complete a drawing package. The objective was to improve the mechanical solution as new information became available. That iterative engineering mindset is fundamental to successful product development. ## Design for Manufacture Manufacturing considerations were incorporated as the machine developed. The project was taking place during a period of significant global supply-chain disruption, increasing the importance of designing around practical manufacturing methods and realistically available components. Design-for-manufacture considerations included: - Part-count reduction - Component simplification - Standardisation - Material availability - Fabrication processes - Assembly access - Tolerance requirements - Fastener selection - Serviceability - Potential component replacement Reducing unnecessary part count was particularly important. Every additional component can affect: **Cost + Procurement + Assembly + Quality + Inventory + Reliability** The design was therefore progressively refined with the objective of achieving the required function without unnecessary mechanical complexity. ## Serviceability Serviceability was considered as part of the machine architecture. Any equipment containing currency-handling mechanisms has the potential to experience jams, contamination or wear. Maintenance access therefore needed to be considered during the design stage rather than after the enclosure had been finalised. The concept considered access to: - Rollers - Currency pathways - Internal mechanisms - Wear components - Cleaning areas - Mechanical connections This reinforced an engineering principle that has remained important throughout my career: **Equipment should be designed for its complete operating lifecycle, not only for initial assembly.** ## Human-Machine Interaction Because the product was intended to be used directly by people, user interaction was another important consideration. The engineering design had to consider how currency entered the machine, how it moved through the system and how it was retrieved. The user should not need to understand the internal mechanical complexity. Good machine design therefore required the internal engineering to support a relatively simple external interaction. This required consideration of: - Currency loading - Entry geometry - Collection points - User access - Visibility - Ergonomics - Potential misuse - Jam recovery This project helped strengthen my understanding of the connection between mechanical engineering and user experience. ## Product Packaging One of the more challenging aspects of special-purpose machine design is packaging. Multiple subsystems needed to fit into one enclosure while still allowing: - Assembly - Wiring - Airflow - Mechanical movement - Servicing - Cleaning - Component replacement A mechanism that performs well independently can become impractical once placed inside a complete machine. The CAD development therefore considered the complete product architecture rather than individual components in isolation. This systems approach is one of the most important transferable skills demonstrated by the project. ## Supply-Chain Considerations The project was developed during a period when global supply chains were under significant pressure. This increased the importance of considering component availability during design. A technically ideal component provides little project value if it cannot be obtained within the required timeframe or at an acceptable cost. The project therefore reinforced the relationship between: **Engineering Design → Procurement → Manufacturing → Project Delivery** This is a principle I later applied more broadly across manufacturing and operational-improvement projects. ## Stakeholder Collaboration Product development required continuous communication between the product concept, engineering requirements and manufacturing considerations. Design iterations needed to respond to stakeholder feedback while remaining technically practical. Three-dimensional CAD models provided a useful way of communicating how the mechanical system would operate and how changes would affect the complete product. This allowed engineering discussions to move beyond abstract descriptions and focus on specific design decisions. ## Project Deliverables My contribution to the project included work associated with: - Mechanical concept development - Dual-path currency-handling architecture - Banknote-feed mechanism development - Coin-handling mechanism development - 3D CAD modelling in Autodesk Inventor - Mechanical component development - Packaging of internal machine systems - Design iteration - Tolerance refinement - Prototype-development support - Design-for-manufacture refinement - Part-count reduction - Assembly considerations - Serviceability considerations - Manufacturing documentation ## Project Outcome The project progressed the Wink Solutions concept from an initial product idea toward a developed mechanical design suitable for continued prototype and manufacturing development. The strongest engineering outcome was the integration of two very different materials-handling mechanisms within a single compact machine architecture. The project demonstrated how special-purpose equipment development requires a combination of: - Mechanical engineering - Product architecture - Mechanism design - CAD - Prototyping - DFM - User interaction - Manufacturing awareness It also provided experience working on an innovative product during an unusual and rapidly changing external environment. ## Capabilities Demonstrated **Special-Purpose Machine Design** Developing mechanical equipment around a specific operational requirement. **Product Development** Progressing an initial idea into a structured mechanical product architecture. **Mechanism Design** Developing different mechanical solutions for flexible banknotes and rigid coins. **3D CAD Engineering** Using Autodesk Inventor to develop components, assemblies and the complete internal machine arrangement. **Design for Manufacture** Considering component complexity, manufacturing methods, assembly and supply-chain availability throughout development. **Prototyping and Iteration** Using prototype feedback to progressively refine geometry, tolerances and mechanical behaviour. **Systems Engineering** Integrating multiple mechanical subsystems within one coordinated product. **Tolerance Management** Recognising the effect small dimensional changes can have on currency-handling performance. **Serviceability** Considering maintenance, cleaning and jam access during the design stage. **Human-Machine Interaction** Developing mechanical systems around how the end user would load and retrieve currency. **Cost-Conscious Engineering** Reducing unnecessary complexity and part count while maintaining required functionality. **Stakeholder Collaboration** Using engineering models and iterative development to connect product objectives with manufacturing reality. ## Career Development This project is important in my career because it required considerably more than creating components in CAD. The real challenge was turning an unusual product idea into a functioning mechanical architecture. That required thinking across several levels: **Component → Mechanism → Subsystem → Machine → User → Manufacturing** Each decision at component level could affect performance somewhere else in the machine. Changing a roller dimension could influence note feeding. Changing an enclosure size could affect mechanism packaging. Changing a component could affect procurement, assembly or servicing. This systems perspective became increasingly important as my career progressed. It helped move my thinking beyond: **“Can I design this part?”** toward: **“How does this part affect the complete product, its manufacture, its operation and its eventual delivery?”** That mindset subsequently became valuable in my product-development, manufacturing, operations-excellence and engineering project work. Today, the same principle applies at a larger scale: **Component → Equipment → Process → Manufacturing System → Project** The Currency Sanitiser project represents an important stage in that progression.