| |
Molding Processes
|
| |
|
| |
Most common rubber
molding processes are
A) Compression Molding
B)Transfer Molding
C) Liquid injection Molding |
| |
|
| |
Compression Molding
|
| |
A piece of uncured
rubber of the right weight is placed between two halves (～150C) of
a mould.
This mould is closed in a press and the rubber is forced to fill up
the cavities in the mould.
The rubber gains heat from the heated mould and cures.
After a certain cycle time, the part can be removed. |
| |
|
| |
|
| |
|
| |
|
| |
Transfer Molding |
| |
Uncured Rubber is forced
through a "runner system" mould with small gate point by
a plunger.
The rubber then fills the cavities of the and the rubber begins to
cure in the heated mould.
Once cycle times is reached, the part is removed from the mould. |
| |
|
| |
|
| |
|
| |
|
| |
Liquid
Injection Molding |
| |
Low viscosity liquid silicone
material is injected into the cavity in the mould much similar to
that of plastic injection.
To increase yield in the production process,1 cavity mould and 2 core
mould are built.
As one core is used, the injected product is removed from the other
core. |
| |
|
| |
|
| |
|
| |
|
| |
Considerations for Injection
Molding |
| |
- only one color molding,
either black or translucent
- on material hardness is possible, ranging between 40-60 ShoreA
- Key height maximum 10 mm
- If conductive pill is to be used, there must be only Circular in
shape
- Preferable for keymats with similar key shapes and heights
- Preferably used in the production of rubbermat for computer
keyboards |
| |
|
Back to Top