Phone Charger Dock
PROJECT NAME:
Phone Charger Dock
INSTITUTION:
Queensland University of Technology
SUBJECT:
DNB404 Product Technology 2: Design for Manufacture
LOCATION
Brisbane, Australia
PROJECT TIMELINE
Semester 2, 2015
PROJECT DESCRIPTION
During our second year of university, semester 2 one of our projects was related to design for manufacture. We were briefed to design a phone charger dock, do prototyping and model the product using SolidWorks.
The aim of this project is to design a simple product detailed enough to be able to be manufactured. This product needs to be functional, aesthetically pleasing and manufacturable. These constraints will help explore and understand how to design a product that fits these criteria and the consideration of appropriate materials and manufacturing processes. This will also help document detailed form and manufacturing specifications of components using SolidWorks and communicating through technical drawing information.
LEARNING EXPERIENCES / CHALLENGES/
DESIGN OUTCOME
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Modeling in CAD and learning about the suitable materials and stress analysis.
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Obtained valuable learning outcomes about design for manufacture.
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Appropriate materials required for a particular context, designing the product to be suitable for the manufacturing process that won’t take long and cost less, while still being aesthetically pleasing and communicating specifications.
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The project has also deepen the understanding of this topic and the skills attained will help future projects relating to design for manufacture
REFERENCES
Consol. (2014). Glass manufacturing Process. Retrieved from http://www.consol.co.za/business/why-glass/glass-manufacturing-process
CustomPartNet. (2009). Injection Moulding. Retrieved from http://www.custompartnet.com/wu/InjectionMolding
Encyclopædia Britannica. (2015). Styrene: styrene-butadiene rubber production process. Retrieved from http://kids.britannica.com/comptons/art-53930/The-flow-diagram-traces-the-emulsion-process-for-manufacturing-styrene
GE Plastics. (N.D.) GE Engineering Thermoplastics Design Guide. Retrieved from https://blackboard.qut.edu.au/bbcswebdav/pid-5968270-dt-content-rid-4827840_1/courses/DNB404_15se2/GE_plastic_design.pdf
Hitachi. (N.D.) Production process for polybutylene terephthalate (PBT). Retrieved from http://www.hitachi.com/businesses/infrastructure/product_site/ip/process/pbt.htm
lesko, jim. (2008). Industrial design materials and manufacturing guide (2nd ed.) . New Jersey, USA: Wiley & sons, Inc.
DESIGN PROCESS
At the beginning of the project, conducted market research on the current phone charger docks that are existing and then start sketching concept designs. From the concept generation chose one design and iterated and refined the design. Then created a low-fidelity prototype on how it will look like and if there will need any design changes based on the user testing. Once the design was confirmed modelled the design in Solidworks and created technical drawings and renders for manufacture.
CONCEPT SKETCHES
Concept Generation: Exploring different designs
Concept Development: Developing the chosen design further: exploring where each component will be, parting lines, screw bosses, electrical components and dimensions.
Low Fidelity Prototype
COMPONENTS
The components in this product are rubber foots that are attached to the bottom of the stand, so it will not move easily, which are made of rubber synthetic rubber styrene Butadiene. The manufacturing process for this part is emulsion, as it is suitable for the material. A dome cover is used for the light bulb which is made of a soft glass lead alkali glass. The dome cover is transparent to see if the LED light is on or off, which is why this material is chosen for this component. The main body of the product is separated into two parts because injection moulding manufacturing process will be used and will need a parting line so the parts can be moulded easily. The body is made of Polybutylene Terephthalate (PBT), as it is able to be used for injection moulding and is a suitable material for an electronic product.
These materials and components also have finishes and surface textures that help grip the stand onto the ground, insulate the electrical components inside the stand and also be aesthetically pleasing. The materials that have been selected for this product are easily manufactured, sustainable and appropriate for the context and functionality of the product. This will be explained more in detail throughout the report. The off- the- shelf components are the charger with a plug attached to the wire, screws, printed circuit board, and LED light bulb.
CAD PROCESSES
Started with drawing up the bottom base of the phone dock. The screw bosses were a bit of a challenge on the angled surface, but eventually overcame it after trial and error.
Also considering how ribs will be placed for the charger and PC board was not easy to do. Also with the flow analysis had to change thickness and add more injection locations so it could cover the whole part.
MATERIALS
For the base of the stand rubber will be used so it will not move by itself. Natural rubber: styrene-butadiene (SBR, AA, BA) has been considered to be used as most natural rubbers are used for shock absorption, vibration control, electrical and thermal insulation and waterproofing. Natural rubber are also sustainable and can be reused for another purpose after its end of cycle. Its manufacturing process are commonly made by injection moulding which makes it cost cheaper. The properties of styrene butadiene (SBR, AA, BA) help to stay in form when a large force is upon the rubber, must be reinforced for acceptable tensile strength, tear-resistance and general durability.
The dome cover is made of a soft glass: lead alkali glass, as it softens or fuse at relatively low temperatures. It contains lead monoxide, which was used for lead crystal and cut glass stemware. It is a good electrical insulator and has little resistance to high temperatures and to thermal shock.
For the body thermoplastics and thermoset materials are suitable for this application. Its characteristics and properties are crystalline, high molecular weight, excellent balance of properties, available in unreinforced moulding resins and glass reinforced grades. Its properties help it to have excellent dimensional stability, durable, low moisture absorption and have various types of finishes.
MANFACTURING
There are a few ways to easily manufacture each components. To manufacture the rubber foots (Natural rubber: styrene butadiene (SBR, AA, BA)) an emulsion process is used. The butadiene and styrene are received, stored and blended with a catalysts while pumped into a reactor. Then it is screened, washed and filtered.
The process for the dome cover would be manufactured will be to gather raw materials of sand, soda ash, limestone and lead as it is the alkali. The raw materials are then stored in large silos and then delivered to batch mixers to be heated in a furnace. The molten glass is then cooled and enters the feeder through cavities in an opening plate, which then would form the shape of the dome.
The body (thermoplastics Polybutylene Terephthalate (PBT)) of the stand will be injected moulded. The part is separated into two to adhere to the standards and save tooling costs and maintenance costs later on. Draft angles are considered that are 1-3 degrees, to help eliminate the use of mould release agents which can adversely affect finishing adhesion. The mould is then injected with plastic material into the injection mould machine towards the injection unit. The mould is then injected out and cools and solidifies into the final part. Using this manufacturing process reduces the chance of sink marks, changes in materials and can mould many different types of detail designs that have thin or thick walls, ribs, bosses, holes and vents.
FINISHES
The finishes chosen for the LED dome cover is glass gloss. This will help the user see if the phone is still being charged or has full battery. For the rubber is textured, so it will be resilient to smooth surfaces. The body is MT11020, as it has a slight rough texture, but also smooth enough to look aesthetically pleasing and can grip easily when moving it.
FLOW ANALYSIS
Top part
From the flow analysis found that it will take less than three seconds for the part to be filled. Cooling time will take 32 seconds. Also there are no major sink marks on the component. Four injection locations were used as one was not able to distribute throughout the part.
Bottom base:
The filling time is 2.84 seconds. Because of the thickness, it might cause fillin problems. Cooling time is 28.38 seconds and there is no risk of materials degradation.
DRAFT ANALYSIS
Conducted a draft analysis and found the sides and back of the part are yellow where the draft is zero. Modifications of the design may have to be implemented so the draft is correct. So for the back part, the vertical line will have to be 91 degrees so a draft will be allowed.
TECHNICAL DRAWINGS
SOLIDWORKS 3D RENDERS