Global Supplier Directory
Supplier Solutions
Whitepaper Library
Calendar of Events
Association Locator
Contents Pages
Market Research
Subscription Center

issue: August 2005 APPLIANCE Magazine

Medical Devices
A Rapid Turnaround

 Printable format
 Email this Article

Using rapid injection molding, American TeleCare was able to integrate electronics and wireless technology into its new medical device at both a low cost and a quick turnaround time.

Specialty patient monitoring device maker American TeleCare Inc. (Eden Prairie, MN, U.S.), produces “telehealth” devices that enable patients to interact with their doctors from home, using a combination of audio and video-monitoring equipment. By sending data to doctors over a phone line, the device gives physicians real-time access to critical information such as heart rate and blood pressure.
Recently, the company set out to produce a new audio-only monitor station called inLife™ to meet the needs of customers not requiring video monitoring. inLife guides patients through the health-monitoring process, gathering and recording such information as blood pressure, pulse, weight, and glucose levels, as well as automatically adding a date stamp to each data record. Peripheral medical devices transmit data to the inLife monitoring station through either serial cables or a Bluetooth® wireless adaptor module. The device also asks patients to respond to health-related questions of interest to their medical providers. The system then transmits the information via phone line to a server, which uploads it into the patient’s record for physician review.

While in the product design phase, American TeleCare was having difficulty obtaining parts that were both cosmetically attractive and geometrically precise, until its engineers discovered rapid injection molding. With help from The Protomold Company (Maple Plain, MN, U.S.), American TeleCare was able to get the low-cost, accurate prototypes and low-volume production parts it needed.

American TeleCare's inLife™ medical appliance is an audio monitoring station that enables users to remotely collect and transmit vital information to their physicians.

Breaking Old Habits

To cost-effectively produce its inLife device, American TeleCare needed an inexpensive way to create prototypes and low-volume production parts, specifically the product’s enclosure box. The company began by using a stereolithography (SLA) model to test their design concept, but knew it required more dimensionally accurate prototypes to move forward with material testing and verification.

“We needed prototypes that would allow us to test the accuracy of the enclosure’s intricate fit dimensions,” John Blomberg, mechanical engineer for American TeleCare, explains. “Without first verifying that the enclosure and circuit board geometries match, we couldn’t proceed with mandatory product integrity testing.”

Company engineers explored several options, including room temperature vulcanization (RTV) molding and steel tooling for conventional injection molded parts, but both posed problems. RTV molding limited the quantity of parts that could be created (25 to 50), while steel tooling was costly and required a long lead time. The company then looked into Protomold’s rapid injection molding, which uses proprietary software and high-speed computer numerical control (CNC) machining to produce aluminum molds. The process creates real injection-molded parts from 3-D computer-aided design (CAD) models in as little as 3 days.

“Before rapid injection molding, we were stuck between rapid prototyping and conventional injection molding,” Mr. Blomberg says. “To accommodate our need for 1,000 to 2,000 prototype parts, we could either make a lot of RTV molds or pay the high cost to create steel molds for injection molded parts. Either way, it’s an expensive process. Rapid injection molding fills the gap by giving us the ability to create 1,000 to 10,000 prototype parts in a timely, cost-efficient manner.”

Exercising Innovation

American TeleCare started the process by uploading its 3-D CAD file to Protomold’s Web site. Within 1 day, the medical appliance manufacturer received Protomold’s ProtoQuote®, an interactive Web-based price quote, including information such as lead-time options, pricing at various quantities, information on a range of molding materials, and design improvement suggestions.

“We’ve become accustomed to sending a design out and waiting up to a week to get a quote back from our prototyping vendors, which can sometimes be a roadblock because we often make design changes in the interim that necessitate re-quoting,” Mr. Blomberg says. “With Protomold’s online system, we made design alterations and checked the price and lead time conditions right away. Getting quotes back in a matter of hours really moved the development process forward, particularly compared to the turnaround timeframes other vendors offer.”

After submitting its initial design, American TeleCare worked with Protomold to fit the enclosure’s design to rapid injection molding’s process capabilities. To stay within the 50-sq-in size limitation in effect at the time (Protomold can now support up to 75-sq-in) and maximum rib heights of 10 times the rib thickness, the engineers reduced the total product size to 49.5 sq in and used an alternative mounting method to stay within the allowable rib heights. After final adjustments to the design, American TeleCare submitted its final prototype order to Protomold, who turned around 25 injection-molded prototypes in 5 business days. “Protomold delivered our prototypes within a week, while delivery from a standard molder would have been 2 to 3 months,” Mr. Blomberg notes.

Benefiting from Program Improvements

With prototype parts in hand, American TeleCare proceeded with various products tests, including emissions and susceptibility tests, as required by the Federal Communications Commission (FCC). Robustness was tested with Highly Accelerated Life Testing (HALT), which subjects a product to high levels of mechanical and thermal stress. The rapid injection molded parts, cast in PC/ABS resin, withstood temperatures ranging from -70°F to 200°F (-57°C to 93°C) without incurring any material failures, such as loose screws or broken ribs.

“With our demanding product development deadlines, it helped to have dimensionally accurate enclosure parts available for testing within a few weeks, versus waiting 2 months or more just to get prototypes,” Mr. Blomberg says. “In fact, the prototype parts from Protomold arrived before our circuit boards, which rarely happens.”

Adding to an impressive delivery time, American TeleCare says the Protomold prototypes also improved cosmetic quality. While previous prototyping methods yielded parts that chipped when dropped and required painting to meet appearance requirements, the Protomold parts maintained a uniform exterior even if chipped or scratched.

“We wanted a durable product that we could snap into place and test rigorously,” says Mr. Blomberg. “Rapid injection molded parts don’t require painting and hold up under long-term wear. Most importantly, they give us the ability to provide a product that will maintain its original cosmetic quality throughout its lifespan with the customer.”

Suppliers mentioned in this article:
Proto Labs

Daily News


Dec 19, 2014: Whirlpool Corp. provides guidance for 2015

Dec 19, 2014: Panasonic to showcase built-in appliances at LivingKitchen 2015

Dec 19, 2014: New residential construction in November 2014

Dec 19, 2014: 2014 U.S. steel production up 0.7% from 2013

Dec 19, 2014: Strong North American PCB Order Growth in October

More Daily News>>

RSS Feeds
Appliance Industry
Market Research


November 2014: Appliance Magazine Market Insight Annual Subscriptions
November 2014: U.S. Appliance Industry: Market Value, Life Expectancy & Replacement Picture 2014
October 2014: Portrait of the European Appliance Industry
September 2014: Appliance Industry Focus: HVAC

Contact Us | About Us | Subscriptions | Advertising | Home
UBM Canon © 2014  

Please visit these other UBM Canon sites

UBM Canon Corporate | Design News | Test & Measurement World | Packaging Digest | EDN | Qmed | Plastics Today | Powder Bulk Solids | Canon Trade Shows