Overmolding, also known as injection molding or insert molding, is an important process employed in electronic connectors used in medical manufacturing.
Overmolding is a process where a single part is created using two or more different materials in combination. The first material (the substrate) is partially or fully covered by subsequent materials (overmold materials) during the manufacturing process. This unique injection molding process that results in a seamless combination of multiple materials into a single part or product. Overmolding allows the wire and connector to be combined, enhancing the assembly features. Similarly, molding over metal inserts creates an interface that provides value electrically and mechanically.
There are a number of benefits to overmolding when it comes to the electronic connectors used in healthcare device manufacturing. We’ll discuss some below.
Safety and quality control
Overmolding enhances quality control and increases component reliability, which can be a matter of life and death in medical devices. Electronic connectors can be color coded or have mechanical features for ease, accuracy, and simplicity of installation reducing the chance for human error during installation as well as the time it takes to manufacture. This is especially important in mobile medical devices that are frequently moved and mated/unmated. In addition, the plastic overmolding can provide alignment and guidance that can protect the pins and help prevent the pins from bending. These “poka-yoke” mistake-proofing solutions mean that if the sockets do not align with the pins, the plastic can mechanically prevent insertion, and not plug into the wrong socket.
Flexibility and strength
In addition to desiring ease of mating and unmating, it is essential that devices that are frequently connected and disconnected are reinforced with overmolding to increase longevity. Overmolding allows for flexibility so the cable can withstand 360 degree strain. It also allows for increased pull strength as well as an increased lifespan due to overmolded connectors being able to withstand more mating cycles than those that are not overmolded. In addition, right angle connectors can protect against even greater cable strain.
Durability, Functionality, and Sterilizability
Overmolding allows for tremendous durability. Overmolded electronic components are protected against dust and debris as well as condensation, pressure, temperature, and chemical exposure. These are all very important features in medical device manufacturing due to the harsh environments electronic connections are subjected to.
For example, it is essential for many medical devices to withstand autoclaving for sterilization. This can require enduring steam at temperatures of 121 degrees Celsius at up to 40psi for 30 minutes. A common example is surgical cautery equipment.
In addition, some medical devices require components that can withstand EMI and RFI, such as MRI machines. Other devices require shielding from Gamma radiation, such as in devices used in radiotherapy for cancer treatment. Other devices still necessitate electrical insulation for the protection for its users, such as in defibrillators. Overmolding can be used for all of these purposes.
Besides all of these important environmental requirements, durability is important to keep medical devices up and running as they should. Repairing medical devices can be incredibly time consuming and costly, in addition to negatively affecting patient care when devices are out of commission.
Customize to meet your needs
Bead Electronics can help you with all of your metal insert pin needs for overmolded applications and cable assemblies and specifically for your overmolded medical connector needs. We look forward to collaborating with you and helping you with your custom contact pin needs. Contact us today to speak with a contact pin and connector specialist.