When it comes to heavy construction equipment, special care must be taken in the design and use of the controls running the machinery. Unlike the use of rubber keypads on indoor heavy equipment, outdoor machines have their own set of needs. Designing molded rubber keypad controls to operate heavy construction machinery takes some forethought to the environment and the challenges facing construction equipment operators.

Heavy construction equipment, like backhoes, graders and cranes, are used to construct bridges, roads, buildings and tunnels. Keypad controls must be durable enough to handle hot temperatures, long runs and hard vibrations. They must be resistant to the elements, including rain, snow and hot sun. Not all materials are suited to these rugged environments; liquid rubber molding is.

Vibrations can cause heavy damage to anything that isn’t securely fastened or sealed. On equipment controls, the molded rubber keypad panel must be able to withstand the motorized vibrating without malfunctioning or breaking.

One of the challenges of designing and creating a rubber keypad for heavy construction equipment is making it easy to see and easy to use. Any accidents or malfunctions in the controls could have catastrophic results. Visibility of the buttons on the keypads through mud and dirt is critical. This can be achieved in a few different ways, including the use of bright colors and a backlit rubber keypad. The background color of the molded rubber keypad is incorporated into the silicone molding process, rather than being painted on top. This prevents peeling and chipping on the surface. Silicone inks create visible colors and laser etching prevents lettering from rubbing or flaking off when the surface is wiped clean. Backlighting enhances each keypad control button when the equipment is running to ensure visibility in the dim environment of the machinery cab.

With heavy equipment running for several hours at a time, the controls are bound to become warm. Add in the blazing sun and the hot temperatures of summer, and the heat-resistant properties of liquid silicone injection molding become very important. Liquid silicone injection molding components can withstand operating temperatures as high as 450 degrees F. They can also be used in cold climates, such as Alaska and New England, providing reliable operation in temperatures as low as -45 degrees F.

Environmental Resistance
One of the advantages to using liquid injection silicone molding on the keypads is the material’s resistance to dirt and water. It can simply be wiped off if it gets wet or dirty. While dirt may harm other materials and make the keypad unusable, this isn’t the case with liquid rubber molding keypads. Another benefit of liquid silicone injection molding is its ability to create a keypad design that prevents penetration of the elements. A single wraparound keypad design will eliminate cracks and crevices where dirt, water and mud can cake and dry. When mud expands as it dries, it can create problems for other materials.

Using a molded rubber keypad for new designs in heavy construction equipment is cost-effective. Once the molding template is made for the device, the parts can be produced in large quantities as needed, with each following the exact details of the specifications. The process and product are affordable and can easily fit into a manufacturing budget.