While many people are familiar with the term micro switch, this little switch has a much longer name. The original name of this little device is a miniature snap-action switch, so named because it required very little force to cause the switch to snap literally to engage.
The use of micro switches is found in all types of applications where instant changes are required. With the very little force required a micro switch is ideal for any sensitive application such as elevators, microwave ovens, fire suppression systems, controls on industrial equipment and machinery as well as in any electrical system control. They are also used in many different switches on vehicles to give instant on/off a response.
Not surprisingly, the micro switch hasn’t been around for as long as many other types of switches and electrical control options. The first model was invented in Freeport, Illinois in 1932 by Peter McGall while working for the Burgess Battery Company. In 1937, it was marketed by the same company under the same product name used today.
In 1950, the trademark and the manufacturing company was purchased by Honeywell Sensing and Control. While Honeywell still hold the trademark on the name many other companies now manufacture these same designs of switches, all going by the term micro switch.
How They Work
Through their design, which includes a “tipping point” mechanism, the micro switch can open and close a circuit extremely quickly. The slightest bit of pressure applied to the actuator in the switch changes the circuit from on to off, depending on the way the switch is constructed and installed.
There is a spring system inside the switch is triggered by a roller, pushbutton or lever movement of the actuator. Through the use of the spring, the small amount of physical pressure on the actuator is amplified, giving the instantaneous snap action inside the switch.
Often with a micro switch or snap action switch you can hear the click of the internal strip. The external force required can be set to require a specific amount of force to provide the best control of the operation of the switch.
The basic design of a micro switch is not complicated, but it is its immediate response to the pre-set amount of pressure which makes it one of the most commonly used switches today in a wide variety of applications.
When you need any micro switch sees us first at Gopher Electronic Company. We offer Honeywell Sensing and Control products to meet all your repair or design needs. To learn more go to www.gopherelectronics.com.