Waterproof mechanically protected sensor package and method of installation

Abstract

Abstract A delicate strain gage or sensing device is bonded to a thin support sheet under laboratory conditions to establish a high quality bond with a minimum of bond line thickness. A frame is placed around the sensing device and over the peripheral portions of the support sheet. Chemically impermeable coatings are applied to the sensor, and a potting compound is poured into the frame to cover the sensing device and support sheet for mechanical and environmental protection. The resulting package protects the delicate sensor on all sides - on the top by the potting compound, on the sides by the potting compound and the sidewalls, and on the bottom by the thin support sheet. The package has sufficient bulk for easy handling, but at the same time the sensing device is displaced from the bottom outside surface of the package only by the thickness of the support sheet. When bonded to a specimen to be tested, the sensing device will be a minimum distance away from the surface of the specimen. The sensor package is installed by preparing the specimen surface, applying a bonding adhesive, and clamping the frame to the specimen. A heat source for curing the adhesive is applied to the specimen at points adjacent to or surrounding the sensing device. A heat sensor device is positioned in a geometric location similar to that of the sensing device with another heat source placed in an adjacent or surrounding configuration. Heat is applied about the periphery of both sensors. The heat sensor is connected to a regulator which controls the production of heat at both the sensor locations in order to maintain the curing temperature at the sensor-specimen interface below the permitted peak value.

Inventors

• 👤 Irving R Grey

Bibliographic Details