DESIGN STORIES
Compartmentalized Bottle
Design Brief
Design a bottle in which the solid and liquid can be kept separated as long as desired and can be mixed within seconds.
Design Idea & Opportunity
A client approached us with a unique idea of a bottle which can be used as a Protein shaker or Baby formula bottle as per the requirement of the user. The client has filed a patent for the same and wanted to know if the concept can be converted into a product. The client had the concept clearly mentioned in the patent but they wanted a product which is aesthetically good, fulfilling all the claims mentioned in the patent and should also be user friendly from the point of view of end consumer
Specific Problem Statement
To design a bottle which has two compartments provided to keep the solid and liquid components separated; until the user desires the solid to be mixed with the liquid.
Design Commencement & Direction
Client provided a simple concept picture (block diagram) of the bottle as per the concepts and claims mentioned in the patent.
As per the claims in the patent, the design of
a compartmentalized bottle should consists of:
- An upper compartment
- A lower compartment
- A disk unit
- A bottle cap
Also other important design conditions stated by the client are as follows:
- The upper compartment should be expandable so that the user can carry desired amount of protein/Gainer powder (in case of protein shaker) or Baby formula powder (in case of Baby formula bottle).
- The disk unit should be separable from the upper and lower compartment
- The upper and lower compartments should be easily removable (so that user can clean them or replace them easily as per the requirement)
So, we started designing the bottle as per requirements and conditions of the client. The CAD modelling was done on a 3D modelling and rendering software by our Design engineer.
Design Iteration 1
We designed an aesthetically good looking model that also fulfils the claims mentioned in the patent. But still as a start-up, we faced following problems:
Problem 1 and the solution:
In the beginning, we faced problem regarding bottle thread standards and selection of proper thread. After searching on internet, visiting 1-2 industries and handling industrial bottles we found out the suitable thread standard for the product which will satisfy the aesthetics requirements and also satisfy end user requirement. We used the bottle standard sp400. The standard clarifies different types of threads as per the bottle requirement and gives dimensions for different type of threads.
Problem 2 and the solution:
After finding out the correct thread class meeting our product requirements and specifications, we 3D printed the bottom section of the bottle and the corresponding mating collar, where both of them were having Right handed threads. The bottom section had extruded threads and the mating collar (Named Lower collar during design) had cut threads. But when we were assembling them we realized there is some issue with tolerances. As engineers we knew the tolerance grades for metals, even there are proper tolerance grades for plastic parts available directly, but the main problem was with the material properties and their effect on 3D printer. This was the main influencing factor affecting standard tolerance grades and also affecting the overall quality of printing.
So, we found out the 3D printer tolerance factor and included it in the design (see more details in Design iteration 2).
Problem 3 and the solution:
As per the requirement of the client (Claim in the patent), we have to design the top section with expandable arrangements so that user can store relatively large amount of solid in powdered form. We searched for different expansion mechanisms like small springs, O ring type of joint, threaded slot. Finally, from the threaded slot idea we decided to go for the expansion mechanism used in sheet container with slight design modifications.
Outcome of design
iteration 1
At the end of iteration 1, we had 1 successful design ready with all tolerances properly calculated. We designed threads successfully, also designed top expandable compartment, bottom compartment (for liquid). We also designed the middle disk unit as per the client's concept diagram and a collar which can be separated into two halves.
Design Iteration 2
After showing the design from first iteration to the client, they were happy for the overall aesthetics of the product and also pointed out some problems about the design of the middle disk with perforations and the collar, which are described below.
Problem 4:
Client discussed a problem with the perforations (from the first iteration), where they said that 'while mixing the liquid and solid there would be a back pressure due to the circular shape of perforations, which are small and few in number. Also, there should be free mixing of the two media with least resistance.' Client also suggested some changes in the external button type of arrangement (provided for aligning or dis-aligning the perforations)
Solution :
We realized that we cannot increase the number of perforations (It would have increased the overall bottle size).So, we made changes in the profile of perforations, such that when perforations are aligned, the user will experience minimum resistance while mixing the solid and liquid parts.
Middle plate with normal circular perforations Middle plate with improved perforations profile
(Design iteration 1) (Design iteration 2)
Problem 5:
Client had an issue with thickness of the collars which was relatively more as compared to overall bottle thickness.
Solution:
Solution was simple we reduced the thickness of the collar section (upper and lower parts).But if thickness of a part having internal / external threads is changed, the 3D printing parameters have to be adjusted. So, we made changes in the slicing parameters and got the part 3D printed.
Outcome of design iteration 2
At the end of iteration 2, we made some useful changes in the perforations profile of the middle disk unit. Also ,we modified the design of collar section where we improved the design aesthetically and made it lightweight which ultimately reduced the overall weight of the 3d printed bottle.
Finalizing the design
In this iteration we made small changes in the design of slot of the expandable section and also embossed some characters on the upper collar section as suggested by the client.
Upper collar section
Lower collar section
We also designed 6 variants of the same bottle with slight modifications as per the client's requirements and also designed 2 attachments for the bottle which are a nibble-holder and a sipper.
Sipper
3D Printed Bottle
6 Variants of the bottle
