Sensors allow packagers to maintain control over a product's environment.
Sensors provide an invaluable service to a packager by keeping constant watch on air pressure, temperature, humidity, and other factors that affect the quality of a pharmaceutical or medical product. By keeping tabs on the environment, the sensor allows the line operator to make adjustments during production that will ensure each product maintains its high quality and that each package is correctly filled and sealed.
Pressure distribution can be measured with a sensor designed with low contact pressures in mind. The Pressurex-micro Imaging System determines pressure distribution between lightly mating or impacting surfaces; it can be used during validation and calibration of sealing die pressure during pharmaceutical packaging. In aseptic packaging systems, the film aids in fulfilling GMP compliance by revealing weak spots, channels, and wrinkles at the sealing surface. The film may also be used to verify and record pressure distribution during equipment setup, preventive maintenance, and product changeover for form-fill-seal machines. Sensor Products Inc., East Hanover, NJ.
A compressed air analyzer measures the mass concentration of contaminants, pressure dew point, temperature, and pressure. The AQT-4 air quality tester features variable set points and broad sensing capabilities. Contamination in the compressed air system can be measured in concentration levels ranging from parts per billion to 100 parts per million. The sensor can sense pressure from 50 to 150 psig, temperature from 22° to 175°F, and pressure dew points from –49° to 80°F. Parker Hannifin Corp., Finite Filter Div., Oxford, MI.

Surface temperatures can be accurately measured with a thermocouple. The True Surface Thermocouple (TST) has a large isothermal area for the measuring junction, which results in about 1/8 the error of a washer-style thermocouple. It was designed to reduce errors in temperature sensing associated with ambient airflow. The TST has a temperature rating of 200°C. Watlow Electric Manufacturing Co., St. Louis, MO.
Registration mark sensors detect colored registration marks on intricate packaging materials. The Colormark II Smarteye registration mark sensors now feature a white LED light source. The Model CMSWL's white light enhances performance when detecting difficult color combinations, including dark marks on dark colored backgrounds. The sensor features a 10-LED contrast indicator, an adjustable offset/EDR, and a built-in connector. The unit is waterproof and resistant to chemicals. Other Colormark sensors are available with red, green, or blue light sources. Tri-Tronics Company, Inc., Tampa, FL.
New 18-mm photoelectric sensors are available for noncontact detection of parts for counting, measuring, and positioning. The range of diffuse, retroreflective, and through-beam Series 18 sensors work well in tight spaces and can detect small objects even at high speeds. All Series 18 photoelectric sensors feature metal housings for protection in industrial environments. Baumer Electric Ltd., Southington, CT.

A subminiature optical sensor is designed to "self-teach" target versus background. The 6K sensor is microprocessor based and can determine for itself the optimum trigger point for the target. The self-teaching mode can be activated remotely for a group of sensors by pushing a button or by machine control. The 6K is available in diffuse, retroreflective, and through-beam sensing modes. Balluff Inc., Florence, KY.

A vacuum and pressure sensor reduces the possibility of flat or spoiled product from reaching consumers. The pressure/vacuum proximity Dud Detector (FS-80IP) works at speeds up to 2200 readings per minute. The unit is available as a stand-alone system or as an optional attachment to the company's fill level inspection systems. The Dud Detector uses an electromagnetic proximity sensor to map the top profile of container closures. Minute differences in closure deflection or inflection can be detected. Industrial Dynamics International Inc., Torrance, CA.