Design News for Mechanical and Design Engineers

H-P Products® VACUFLO® FC300® Central Vacuum System. This low cost ($309), compact (1-ft diameter, 2.5-ft tall, 22 lb) central vacuuming system is designed for homes up to 2,500 ft². But engineers were challenged to match the ability of larger-systems to move air at 115 cfm and keep the price down. Using a motor plate made from DuPont Zytel® nylon resin, they were able to accommodate the different-size ac motors and mount the printed-circuit control boards for this and other models, says Engineering Manager Darrell Nieschwitz. Such commonality reduced costs for all models and the plate's molded features cut parts count by 15-20%. A port in the plate accommodates a valve that feeds the cyclonic particle separator before the airstream passes through a pleated cartridge filter. Engineering Manager: Darrell Nieschwitz, dnieschwitz@hpproducts.net http://rbi.ims.ca/3090-534

MGE UPS Systems Evolution Fuel-Cell UPS. Unlike battery-based uninterruptible power supplies (UPS), this zero-emissions, fuel-cell powered unit is only limited in duration by the size of its pressurized hydrogen supply. The fuel is contained in 31- or 51-inch high Praxair (www.praxair.com) cylinders for backup of four to 24 hours. Engineers sized the system to fit standard 19-inch industrial racks—typically made up of three 1-kW Ballard Power Systems (www.ballard.com) Nexa® RM (5U-size) proton exchange membrane fuel-cell modules and the 2U Evolution UPS itself. The design hinges on Ballard's commercially available fuel cells, which feature compensation circuitry and built-in inverters that account for the larger voltage swing during discharge (30%) compared to that of batteries (20%). Product Manager; Alan Katz, info@mgeups.com http://rbi.ims.ca/3090-535

Andor Technology iXon Intensified Camera. This camera's single-photon detection feature delivers the sensitivity to see dim, fluorescent-dyed cells and single molecules. Key is the 90+% quantum efficiency (QE, the fraction of photons converted to electrons) of Andor Technology's electron-multiplying CCD (EMCCD) imaging detector array. Engineers obtained such efficiency by electron multiplying (amplifying) directly in the array's silicon structure as opposed to using a separate image intensifier tube where resulting QE can be at best 30%. The detector incorporates a shift register that transfers data from the image area to an onboard gain register, which then sends the information through an output amplifier. Low light Imaging Specialist: Colin Coates, information@emccd.com http://rbi.ims.ca/3090-536

Skimeter FLEXMETER Snowboard Guard Glove. Guards adapted from in-line skating do not protect against wrist hyperextension when a snowboarder's hand impacts the snow, and they limit wrist mobility. And gloves with short, rigid plastic guards may lead to some radius (thumb-side bone in the forearm) fractures. A trauma specialist teamed with design engineers to develop this wrist guard for snowboarders that runs the full length of a glove. The guard, made from flexible DuPont Hytrel® thermoplastic, smoothes out and redistributes the compressive load over a larger area, and places the greatest stress away from the growth platelets of the lower arm, critical for a young person's proper growth. Engineers chose Hytrel polymer for its good flow characteristics during molding and its low-temperature properties (a constant flex modulus, and high fracture toughness). U.S. Product Developer: Rick Howell, rick@readerswindow.com http://rbi.ims.ca/3090-537

Motorola XTN™ Two-Way Radio. Engineers designed this entry-level radio for construction, manufacturing, and light industrial (MilSpec810, IP54) use around the world. By designing mechanicals concurrently with the circuit boards, the engineers allowed the same housing to accommodate three different boards (VHF, UHF, and PMR446) and a common battery. In addition, snap-on, front-face bezels tailor the radio to any of 13 software-based models, which are stand-alone programmable without a PC. Via a multi-unit charger, a single radio can simultaneously program the settings of up to five radios using proprietary serial messages. Chief Engineer: Billy Robertson, mmic@hillandknowlton.com http://rbi.ims.ca/3090-538