Funnels are commonly used in Indian kitchens for transferring oil, water etc to small mouthed bottles.

>> One common problem with existing funnels is when some liquid is poured in it, the liquid clogs up as the air inside the bottle can not come out and creates pressures in the opposite direction of the liquid flow.

>> After pouring liquid using funnel the liquid stuck to the inner side of the funnel drips when the funnel is taken out from the bottle which makes it a messy job.

Concepts
The existing form of the injection moulded funnels has directly been derived from the old funnels which were made from bending sheet metals, and thus based on simple conical or cylindrical shapes. In fact it has a benefit too; almost the entire mold (apart from any hook which protrudes out from funnel) could be made by a lathe machine.

And I realized that there lies the root of the problem! As most of the bottles have round mouth the funnels tend to fit the mouth which blocks the air to come out.

After trying for several solutions I found something which is perhaps the simplest possible solution, that is, make the funnel in such a way that it does not fit to the mouth of any bottle! As most bottles are with round mouth, it should have any shape other than full circular cross section which won’t fit to the circular mouth of the bottles/containers. After reaching this solution all other previous solutions started looking really silly!

Based on this principle any form could be made which would not have the clogging problem. But I also considered other issues related with funnels mostly in relation to the Indian kitchens. Like the way it’s kept or hung.

My approach to the form was to make it different from the existing funnels exploiting the capabilities possibilities of modern injection molding of organic form.

The form is organic and free flowing keeping one side almost flat which helps to form the channel for air outlet and at the round mouth of bottle as well as gives a vertical orientation while hung.

The end is chopped off at an angle which gives a sharp end to the form which helps the liquid to accumulate quickly thus dripping outside the container is prevented.
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Display_Flow After freezing on the final concept I made a number of prototypes. As the form is symmetrical only at one axis the same mould can not be used for making both halves of the form, so I made 2 pieces positive moulds using medium density composite boards. Then I vacuum formed 2mm. polystyrene sheets to get basic forms in 2 halves and then joined those two parts together using chloroform to get the desired form.

I made another version of the funnel in which the flat side is given a concave surface, which helped to achieve more interesting form. After finishing the funnel I painted the funnel with white enamel paint.

Although this prototype only simulates opaque white plastic, but I also suggested translucent polyurethane or rubber in various colours as other option. The moulds for injection-molding would be in 2 or 3 parts depending upon of the variations of the design.

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