Cavity Pressure Measurement in Micro Injection Moulding Tooling
Cavity pressure measurement in micro-injection tooling decouples machine dynamics from cavity fill, eliminating part weight variance and micro-defects.
Fiber Optic Pressure Sensor
Meaning
Optical measurement transducers detect cavity pressure changes by measuring light intensity modifications across a micro-diaphragm inside an injection mould. A fiber optic pressure sensor delivers high frequency pressure signals without susceptible electronic components sitting inside the hot steel mold body. The sensor governs precise cavity filling monitoring, gate seal identification and switchover trigger accuracy in micro moulding application setups.
It stops functioning if the fiber cable fractures or when plastic resin contaminates the optical diaphragm face.
Optical Sensing
Light transmitted through glass fibers reflects off the backside of a metallic diaphragm that flexes under melt pressure. Measuring changes in reflected light intensity yields microsecond pressure data that reveals true polymer flow front behavior. Installing a fiber optic pressure sensor allows control systems to capture fast pressure spikes during high speed injection steps.
Datasheet response times for optical sensors far exceed traditional strain gauge instruments, enabling tight weight control in thin wall parts.
Immunity Profile
Electromagnetic interference from heavy electric motors and servo drives disrupts conventional electrical sensor wiring.
Thermal Resilience
High performance polymers such as PEEK and LCP require mold processing temperatures exceeding three hundred degrees Celsius. A fiber optic pressure sensor withstands these harsh thermal conditions because sensitive signal processing electronics reside in a remote amplifier box outside the tool. Virgin engineering resins processed at extreme temperatures do not degrade the optical glass leads.
Long term signal stability minimizes calibration overhead during long medical part production runs.