A bright idea for the operating room

March 22, 2007
Engineers at Merivaara Oy, in Finland had to redesign a medical examination lamp so it wouldn't get too hot.

Engineers at Merivaara Oy, in Finland had to redesign a medical examination lamp so it wouldn't get too hot. It used housings made from extruded aluminum profiles with injection-molded plastic end caps and faceted aluminum reflectors.

According to Jyrki Nieminen, R&D head for Merivaara, "The most important concern was the excessive heat generated by the lamp's metal reflector." Too much heat makes patients uncomfortable and also raises operating and exam room temperatures, affecting clinical staff. In addition, designers wanted to reduce costs by consolidating parts via metal-to-plastic conversion. "The switch to plastic would give us more flexibility for future versions of the lamp," Nieminen says.

The company chose a 30% glass-fiber-reinforced blend of polybutadiene terephthalate (PBT) and polyethylene terephthalate (PET) to replace the aluminum lamp housing. The Valox 865 resin, from GE Plastics, Pittsfield Mass., is rated for temperatures to 120°C, withstands harsh cleansers, and can be custom colored.

Designers determined that a high-performance polytherimide (PIE) was the best option for lamp reflectors. Reflectors injection-molded from Ultem 1000 PIE, in combination with aluminum metallization, produce what's called a cold mirror — it directs visible light downward while radiating infrared heat upward toward the top of the lamp and away from the patient.

Another benefit of Ultem PIE is its ability to be metallized without pretreatment, says Rob de Jong, GE Plastics industry manager. "GE has devoted significant resources to developing lighting for the health-care industry. The Ultem resin family delivers improved performance compared to metal reflectors in terms of temperature management, dimensional stability, and lighter weight."

The Merilux X1 lamp redesign let designers eliminate secondary processes. Two injection-molded halves replace a three-part metal assembly that had hard-to-clean through-holes and hard-to-reach surfaces — an important consideration in healthcare environments. In addition, GE provided an exact color match, thus eliminating a costly secondary painting step.

Injection molding let designers mold in assembly elements and fixture points instead of adding them later, thus reducing cycle times. Injection molding the reflector improved faceting and light-source positioning.

MAKE CONTACT
GE Plastics (413)448-7110,
geplastics.com
Merivaara Oy, + 358 3 3394 611 www.merivaara.com

Sponsored Recommendations

The entire spectrum of drive technology

June 5, 2024
Read exciting stories about all aspects of maxon drive technology in our magazine.

MONITORING RELAYS — TYPES AND APPLICATIONS

May 15, 2024
Production equipment is expensive and needs to be protected against input abnormalities such as voltage, current, frequency, and phase to stay online and in operation for the ...

Solenoid Valve Mechanics: Understanding Force Balance Equations

May 13, 2024
When evaluating a solenoid valve for a particular application, it is important to ensure that the valve can both remain in state and transition between its de-energized and fully...

Solenoid Valve Basics: What They Are, What They Do, and How They Work

May 13, 2024
A solenoid valve is an electromechanical device used to control the flow of a liquid or gas. It is comprised of two features: a solenoid and a valve. The solenoid is an electric...

Voice your opinion!

To join the conversation, and become an exclusive member of Machine Design, create an account today!