The Project: A durable material was needed from which to fabricate protective bumpers for a portable pain management device.
The Solution: A thermoplastic vulcanizate alloy was selected for its excellent surface quality, easy processability, high tear strength, and aesthetic benefits.
Biowave Corp. is a medical device manufacturer whose pain therapy products help patients manage pain and reduce the use of medications, such as opiates. Its devices deliver a therapeutic electrical signal into deep tissue in the body, blocking the transmission of pain. In addition to a version for clinicians, the company offers the BiowavePRO non-invasive neuromodulation system designed for individual use by athletes to reduce pain and enhance rehabilitation.
devices deliver a therapeutic electrical signal into deep tissue in the body,
blocking the transmission of pain.
In designing the housing for the BiowavePRO, Biowave had several objectives. The portable device, targeted at college and professional sports teams, had to be durable enough to handle a sports environment—travel on buses and planes, use in locker rooms, and the risk of being bumped or dropped. The design called for two protective bumpers on the sides of the housing to provide a non-slip grip for the user. In addition to durability, these bumpers needed resilience for a comfortable feel and the ability to incorporate membrane switches.
An important goal was brand distinction, including a sleek, simple design and signature color. To achieve this, Biowave wanted the bumpers to give the appearance of being integrated with the front and rear housing and to be custom colored.
Molding & Material Recommendation
Biowave consulted PTA Corp., its molder, for guidance on materials for the housing. PTA turned to PolyOne GLS Thermoplastic Elastomers due to a longstanding relationship and confidence in the company’s ability to provide the best material in a short timeframe. Polyone recommended its Versalloy XL 9070X-1 thermoplastic vulcanizate (TPV) alloy for excellent surface quality, easy processing with excellent flow, and high tear strength. It can also be easily colored for excellent aesthetics.
PolyOne provided custom coloring and rapid delivery of the material to meet a tight production schedule. The bumpers were molded separately and then slipped into channels between the upper and lower housing components instead of overmolding them onto the housing. This approach maintained the streamlined design while controlling costs.
From a processing standpoint, PTA was very satisfied with the moldability of the Versalloy TPV, which delivers a high-quality surface finish and resists striations that can occur with other elastomers.
Delivering a Value-Added Solution
The Versalloy TPE material is helping Biowave win and retain customers among sports teams, many of which purchase multiple devices for their players. Its high performance under rugged conditions helps generate recommendations and repeat orders. Currently, nearly 40 professional teams and 17 college programs use BiowavePRO
The Portable device had to be durable enough to handle a sports environment—travel on buses and planes, use in locker rooms and handle risk of being bumped or dropped.
Usability: Versalloy material makes a major contribution to the ruggedness and versatility of the device. Its toughness prevents the bumpers from shredding or marring, even with extensive handling.
Portability: The ability to use the BiowavePRO practically anywhere is of great value to mobile sports teams. Versalloy TPV contributes light weight and a sure grip that is important for safety and precision.
Cost savings: Molding the bumpers separately and inserting them into the housing keeps costs down yet provides the seamless appearance of overmolding. Creating a two cavity tool for the bumpers saved PTA 70% over the cost of an overmolding tool and reduced scrap rates typical with overmolded housings by 80%.
Joe Kutka is the global market development manager, healthcare for PolyOne GLS Thermoplastic Elastomers. He is responsible for research and development efforts to support critical new market trends on an international scale. Kutka can be reached at 815-759-2607 or firstname.lastname@example.org.