Almax-RP manufactures custom membrane switches. We have over two decades of experience. Our engineering team can provide you with the most reliable membrane switch design possible. If your keypads are designed incorrectly, then they can fail in the field. Keypad failures in the field can ruin your reputation with your customers. Don’t trust your success to the membrane switch amateurs. Choose Almax-RP, the expert membrane switch company.
In addition to offering responsive onshore engineering and manufacturing, we offer cost effective offshore manufacturing. Our parent company, Almax Manufacturing, owns and operates a large factory in Dongguan, China. This means that we can support your project from the design phase, all the way through mass production.
What Are The Advantages of Custom Membrane Switches?
- Membrane switches are easily cleaned, which is critical for medical or laboratory applications. The graphic layer provides a sealed smooth layer that is easily wiped down, and can be sprayed with standard cleaning chemicals.
- IP67 waterproof gaskets can be designed into a standard keypad assembly.
- Branding is simple and straightforward! Almax–RP can easily include your branding, logos and artwork in your keypad.
- They are extremely durable and can withstand heavy use for many years.
- Our engineering team can design backlighting into most keypads with side fire LEDs and Light Guide Film.
- Whether you are looking for a simple design, or a more complex build with backlighting and EMI shielding, Almax–RP can design a solution to fit your needs.
Design Options for Custom Membrane Switches
- Embossed buttons
- Pillow embossing
- Rim embossing
- Clear display windows
- Surface mounted indicator LEDs
- Backlighting with light guide film or fiber optics
- IP67 waterproofing
- EMI & ESD shielding
- Custom graphic overlay branding and artwork
- Tactile or non-tactile buttons
- Circuit layer construction
- Printed silver ink on flexible PET
- Flexible printed circuit (FPC)
- Printed circuit board (PCB)
- UV resistant graphic overlay material
What Are The Layers of a Membrane Switch?
- Graphic Overlay: The graphic overlay is the top layer that is visible to the end user. This layer typically has printed graphics that show how to use the device. This layer will also have clear windows for LCDs and touch screens.
- Spacer Top: The spacer top adhesive goes on top of the dome retainer and below the overlay. This layer adheres the graphic overlay to the dome retainer.
- Dome Retainer: This layer holds the metal domes in place. It is typically made out of thin flexible PET. Typically is this layer is 0.003″ to 0.005″ thick.
- Spacer: The spacer layer goes on top of the circuit layer. This layer has ventilation channels that allow air to be displaced when the tactile switches are actuated. The spacer adhesive bonds the circuit to the dome retainer.
- Circuit Layer: We print conductive inks on thin flexible PET to make our membrane switch circuits. We also use copper flex circuits (also known as FPCs) and PCBs for some of our circuit layer constructions. If your design has metal domes or embedded LEDs, then these components will be mounted on the circuit layer.
- Mounting Adhesive: Mounting adhesive is the bottom layer of a typical membrane switch. This adhesive bonds the finished keypad assembly to your housing or equipment. We use permanent adhesives made by 3M. Let us know if your assembly needs to bond to a powder coated metal or another Low Surface Energy (LSE) material so we can designate an LSE adhesive.
How Do Custom Membrane Switches Work?
Each tactile switch contains a metal dome. When this dome is pushed down, it makes contact with the printed circuit. This closes the circuit and allows current to flow, which triggers the desired response from the device. When the user removes pressure from the button, the circuit returns to its open state. This is why membrane switches are considered momentary, normally open switches. The circuit is momentarily closed when a person presses a button, but then the circuit returns to its normally open state when the pressure is released.
What Information Does Almax-RP Need to Quote a Custom Membrane Switch?
- Mechanical specifications for your keypad assembly including outside dimensions, cutout locations, display window locations, button locations, and LED locations (DXF, DWG, or PDF file types preferred)
- Environmental considerations including IP67 waterproof requirements or continuous outdoor UV light exposure
- Artwork files for your graphic overlay (AI or PDF file types)
- Does your application have an antiglare requirement for clear display windows?
- Will your custom membrane switches be operated by a user wearing gloves? If so, we will design your keys to have maximum tactile feedback.
How to Get in Touch with Almax-RP about Your Membrane Switch Project
You can fill out our contact form to get in touch with us. If you would like a quote, then please send us your drawings. You can also schedule a free Design For Manufacturing (DFM) review with our engineering team. A DFM review is a great opportunity to reduce project costs and lead times before we get started with manufacturing.
We are ready to support your project whether your company makes medical devices, industrial equipment or consumer electronics. Our goal is to be a partner in your success. We look forward to working with you.