Advancements in user interface assembly construction methods are often overlooked in the HMI applications as it is usually an afterthought and too many people assume that the older graphics, adhesive, rubber, and backlighting technologies are still the same. This is not the case, especially in medical applications.
Continued improvements to the human-machine interface (HMI) manufacturing process across entire electronic industries that were once seen as too expensive for a lot of applications, are now within reach of design budgets.
There is good reason that programmable logic controllers (PLC) are used as a user interface in a large number of applications. These robust devices are commonplace on factory floors controlling equipment, in processing plants monitoring operating conditions, and even used in portable devices exposed to harsh environments.
Membrane switch style user interfaces often face long-term outdoor UV, chemical, and moisture exposure. To help improve membrane switches, there are several considerations that apply. Veteran manufacturers with substantial engineering experience ensure the optimal result of each application. Numerous solutions for can be provided specific to any given industry.
Designers and manufacturers of silicone rubber keypads understand they are used for a wide range of industries and applications. Keypads are used extensively in both consumer and industrial electronic products as a low cost and reliable switching solution. In specific applications rubber keypads may be used in harsh outdoor environments that must withstand hundreds of actuations on a daily basis.
As a leader in user interface technology, we frequently get asked the question; what kind of user interface is the best option for my application. Human Machine Interface (HMI) assembly designs are dependent on the application, housing, and the environment they will be used in. Choosing the right option and material is a key component.
Packaging for user interface assemblies for shipment to customers is the last step in the manufacturing process. Epec pays as much attention to packaging detail as to design and manufacturing of custom assemblies. Each custom assembly part number is by nature different size, mass, and shape because it is custom. However, styles of user interfaces can be grouped in several categories. Experience has shown the type of packaging that works best is based on complexity of construction, shape, size, mass and shipped unit volume. No one packaging solution works for every assembly style.
This blog post addresses custom user interface functional test schemes that are completed prior to shipment. Generally, the first user interface assemblies shipment are for First Article acceptance testing where customers fully examine the first units for mechanical and electrical compliance to all engineering drawing and specifications.
In some applications including marine environments, medical devices, and consumer electronics there is a possibility for the user interface control panel to be exposed to water or liquid solvents. In these situations, it is critical that the electronic components are completely sealed from any outside containment's that could damage the built in electronics.
Many applications are better suited using a "membrane switch" (low profile, flat surface keypad assembly) with a rigid printed circuit board replacing screen-printed silver conductors on polyester sheets.
Printed circuit boards with gold plated switch contact pads and gold plated dome switches greatly improve the reliability of your application. Types of improved reliability consist of longer operating life, lower switch resistance and contact bounce.