What are the performance characteristics of a live hinge?
Live hinges look very clean and easy due to the beautiful nature of the adjacent and smooth curves. There is room for creativity and new design possibilities can always be explored.
There is a wide range of applications for live hinges, and a new solution can be adapted for most injection prototypes that require the use of hinges. The simplicity of live hinge designs makes them great for such purposes.
Because live hinges are made of plastic, there is no possibility of rust like metal hinges.
Because they are made from a single part, they are typically much cheaper to manufacture than other types of hinge mechanisms (many of which require labor to assemble, multiple tools to produce, etc.).
The fact that the hinge is included in the design and construction of the prototype significantly reduces the cost of living of the hinge.
Live hinges are very durable.
The absence of a large number of parts makes them very strong and almost unacceptable against wear or damage of parts.
Some living hinges can make millions of rounds before any wear or tear occurs.
Note: Prototypes of hinges produced by 3D printing have significantly less ability to withstand repeated bending.
This is because existing 3D printing materials are not equivalent to polypropylene in terms of material properties.
Live hinges have exceptional flexibility in the axis of rotation of the hinge.
Live hinges experience almost no friction because they are made of one piece.
This is a significant advantage over traditional hinges.
Properly produced live hinges will last the entire life of the part.
They must be able to bend hundreds of thousands to millions of times without showing significant wear and tear.
Live hinges do not need maintenance because they will only break down if exposed to abnormal conditions.
10–Range of motion:
Live hinges are typically designed to create 180-degree angular motion.
Some are not designed to limit bending to a certain extent and rotate well beyond 180 degrees, while others ensure that the hinge does not bend at a certain angle (eg 90). Degree).
Live hinges are very limited in bearing loads (whether tensile stress, compressive stress or shear stress).
This is one of the major limitations of live hinges.
Plastics generally have low melting points.
Therefore, as the temperature increases and approaches the glass transition temperature (the temperature at which it begins to move from a liquid to a solid state), the hard materials become less.
1–Using CNC machining:
For a live hinge prototype CNC machine, you start with a piece of polypropylene (PP) sheet.
Plastic gradually separates from the primary block of material (a process known as subtraction production).
To approve the design and prototyping of 1 to 10 parts, it is faster and much cheaper to cut the original parts with live hinges from polypropylene raw materials.
Many people find this impossible – for a number of reasons – one of which is the tendency of PP to chew gum when machined accurately.
Fortunately for us, these people are wrong.
In fact, polypropylene can be turned into prototype hinges. Creative mechanism technicians can cut very small and precise hinges with a machine, from an infinite variety of designs to a precision of 0.005 inches on our multi-tool CNC machine.
2– Using injection mold:
Creating a prototype of a live hinge using an injection mold requires the design and construction of an injection mold tool (aluminum or steel block with an internal cavity in the shape of your prototype).
Placing hinges on injection molding tools can be difficult, and designing and manufacturing injection molding tools is much more expensive than cutting one or two prototypes on a CNC machine.
We recommend this method when you need several hundred to thousands of prototypes for items such as pre-production testing purposes.
At such a scale injection of parts from final materials is much more efficient than cutting much more efficient than CNC cutting in many of them.
In addition, for the sale of samples that require fifty to one hundred prototypes, the use of injection molding is probably a better option, not only because of the fast rotation, but also because the finish is better than the CNC cutting prototype.
This is very important in sales sampling, where it is desirable that the prototype be as close as possible to the final product.
Note:Even in such cases, it is good to first cut the CNC specimens to make sure that they work properly before investing in the injection molding tool.
Live hinges are very useful in a wide range of applications.
They are made of polypropylene plastic.
Accordingly, they basically last forever.
One of their main limitations is that they do not support heavy loads well.
The best way to produce a live hinge depends on the number you want. For small projects where 1 to 10 hinge prototypes are required, we strongly recommend CNC machining them from polypropylene blocks.
For larger projects, which are 100-1000 prototypes, we recommend injection molding. When it comes to final production, the obvious solution is injection molding.
If you need help with any of the above solutions, please get in touch with Artan Petro Kayhan mechanisms.
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