What is a micro switch
A micro switch is a quick change-over switch that is actuated by pressure. The micro switch is a contact mechanism with a small contact interval and a quick-action mechanism. It uses a specified stroke and a specified force to switch the contact mechanism. It is covered by a housing and has a drive outside. A kind of lever switch, because the contact distance of the switch is relatively small, so it is called a micro switch, and it is also called a sensitive switch.
Classification of micro switches
1. Small micro switch
The general size of a small micro switch is 27.8mm in length, 10.3mm in width, and 15.9mm in height. In terms of parameters, there are different changes such as high capacity and low load.
2. Subminiature micro switch
The general size of the ultra-small micro switch is 19.8mm in length, 6.4mm in width, and 10.2mm in height. It has different functions such as high precision and long life.
3. Super small micro switch
The general size of the super small micro switch is 12.8mm in length, 5.8mm in width, and 6.5mm in height. This type has an ultra-thin design.
The function or purpose of the micro switch
Although the micro switch is small, it plays an irreplaceable role in our daily life, realizing automatic control and safety protection in equipment that needs to frequently switch circuits. At present, it has been widely used in electronic equipment, instrumentation, mining, power systems, household appliances, and military fields such as aerospace, aviation, missiles, and tanks. In addition, they can also be used in computer mice, car mice, automotive electronics, communication equipment, military products, as well as testing instruments, gas water heaters, gas stoves, small household appliances, microwave ovens, rice cookers, and floating ball equipment., Medical equipment, building automation, power tools and general electrical and radio equipment, 24-hour timer.
Micro switch operation method
The operating method of the micro switch affects the performance of the switch. Please pay attention to the following during operation (see the figure on the right).
Use a smooth-shaped switch operating body (cam, stopper, etc.). The drive rod of the switch is quickly recovered, and when it receives an impact, it may cause damage to the drive rod and shorten the life.
Please do not apply an unbalanced load on the drive rod during operation. Otherwise, local friction may cause damage to the drive rod and shorten the service life.
Please operate according to the operating direction of the drive lever. In the needle button type, press the button vertically.
Please operate the ball pendulum and R-shaped pendulum from the direction shown in the figure below.
Set the angle θ of the cam and stopper such as the ball pendulum within the range of 30 to 45°. If the angle is too large, it will cause abnormal lateral stress on the pendulum rod.
Machining the drive rod will exert excessive external force on the internal mechanism of the switch, causing its characteristics to change and the switch to fail.
When using the external swing lever as an operating body, in order to determine the applied load according to the operating load of the switch, please confirm the material, plate thickness, etc.
Precautions for the use of micro switches
1) When fixing the switch body, use M2 screws to fix it on a smooth surface with a torque of 0.098N·m or less. In addition, in order to prevent the screws from loosening, it is recommended to use washers at the same time.
2) Please note that the action body should not directly exert force on the button or exciter in the free state, and exert force on the button in the vertical direction when using it.
3) The operation setting after operation is based on the O.T. value of 70 [%] or more as the standard. In the case of a switch, do not set the operating body at the operating limit position, so as to avoid opening and closing and over-travel caused by impact and shorten the life.
