With more technological advancements a lot of improvements have been witnessed in different types of appliances. A membrane switch is a human-machine interface made of many layers of thin plastic films or other flexible materials. The surface of plastic films of membrane switches have graphic inks or conductive materials laminated or printed on them so that these switches can be used or controlled. The popularity of appliances with membrane switches is increasing due to their efficient and compact construction. In this article, we will learn about the membrane switch overlay and the benefits of membrane switches.
A membrane switch is constructed with several layers of flexible materials that are assembled using heat sealing films or pressure-sensitive adhesives. The main components of membrane switches are-
• An overlay having graphic elements
• An electric circuit having conducive tracks
• Metal or plastic domes
• Circuit tail
• Spacer
• Terminals
Overlay of a membrane switch
The overlay of a membrane switch is the outermost layer of the switch. It is the layer that is exposed to the external environment so it is made of materials having good flexibility, durability, clarity, and resistance to water and chemical. Here are the two most common materials that are used for making the overlay of a membrane switch.
Polyester- It is commonly known as polyethylene terephthalate or PET. It is a plastic material that has good flexibility, clarity and chemical resistance. Due to its high flexibility, it is more durable compared to other materials. Polyester is preferred to make membrane switches with tactile feedback.
Polycarbonate- Polycarbonate is preferred for making membrane switches for industrial appliances because they are abrasion resistant and have inherent flame-retarding property without using extra surface treatment like hard coating. Compared to polyester polycarbonate is more economical.
Other materials used for making the overlay of membrane switches are PVC, vinyl, and acrylic.
Domes of membrane switches
Domes in a membrane switch offer tactile feedback. Domes are made of plastic or metal. When dome is depressed using force, it activates the switch. Domes are of different sizes and shapes such as-
• Oblong
• Round
• Triangle
• Four-legged
Benefits of membrane switches
Here are the benefits of using a membrane switch.
• Membrane switches are made of very thin materials so they have thin and compact profile. They help in space optimization in any household, industrial or commercial appliance.
• It is easy to make graphics design of membrane switches. The artwork or graphics designs for the membrane switches can be created using AutoCAD, Adobe Illustrator, SolidWorks etc. The artwork is digitally printed on the overlay using digital printing technology.
• Membrane switches are made of materials that are resistant to water, chemical and other external components.
• Membrane switches are easy to clean and maintain.
• If needed, membrane switches can be created to provide tactile feedback which is required in appliances that have a risk of equipment shutdown or malfunction. For more information visit here: CSI Keyboards, Inc.
