This cavity sensor transmits a signal which is triggered by a metal butt joint with the melt during the mold filling process (see Mold filling phase).
When applied in die casting procedures, the metal position in the cavity can be determined in real time during the injection process by using a metal front contact sensor (MFCS). If several sensors are attached to the mold, the mold filling process can be exactly understood. This way, the following reasons and effects on the mold fillinf can be evaluated and verified:
1. Mold temperature variations
2. Metal temperature variations
3. Injection system changes
4. Lamellar or abrupt (too turbulent) mold filling
5. Separating agent changes
6. Check of the results from the numeric mold filling simulation
It is useful to use the sensor also for starting the second phase (see Changeover point), the third phase (pressure intensification phase) and for triggering the squeeze function. Independent of the metal quantity, a highly accurate repeatability is guaranteed. The advantages of the implementation of a metal front contact sensor are the following:
To measure these functions, a high sampling rate of the measureing device is required, which is fulfilled with a 4 to 5kHz frequency. Therefore, the metal front contact sensor can be used to determine the following parameters:
Additional references:
Vacuum sensor
Multi airpipe sensor system
Mold filling control sensor
Mold cavity pressure sensor
Metal front temperature sensor
Air flow sensor
Humidity sensor
Residual gas sensor