Contents
- 1 What is a Micro Switch?
- 2 How Does a Micro Switch Work?
- 3 MicroSwitch Terminologies
- 4 Types of Micro Switches
- 4.1 Flexible Rod
- 4.2 Hinge Roller Lever
- 4.3 Rotating Operation
- 4.4 Reverse Operation Hinge Roller Lever
- 4.5 Spring Short Pin Plunger
- 4.6 Leaf Lever
- 4.7 Simulated Roller Leaf Lever
- 4.8 Simulated Roller Lever
- 4.9 Pin Plunger
- 4.10 Leaf Spring
- 4.11 Spring Pin Plunger
- 4.12 Roller Leaf Spring
- 4.13 Cross or Panel Mounted Roller Pin Plunger
- 4.14 Hinge Lever
- 4.15 Panel Mount Pin Plunger
- 5 Features of MicroSwitches
- 6 Advantages of Using a Micro Switch
- 7 How to Use a Micro Switch
- 8 Mounting of Micro Switches
- 9 Micro Switch Applications
- 10 Final words
What is a Micro Switch?
A microswitch is a minute snap-action device that requires little force to function.
What is a snap action switch device? It means when you touch the device with a particular stroke position, it switches instantly. And this happens without an operating force or hit operating speed. Further, you can rely on the micro safety switch for fast and efficient use.
In addition, this switch is usually NO (normally open) or NC (normally closed).
How Does a Micro Switch Work?
Typically, when the microswitch touches an object, the contacts change position. That said, the working principle of this switch includes:
When you depress or switch the actuator:
- The circuit that’s (NC) Normally Closed will open
- The circuit that’s (NO) Normally Open will close
When you release the actuator, or it’s in a rest position:
- The circuit that Normally Closed will carry the current
- The Normally Open circuit can insulate electrically
Also, the micro-switches have vital features like the tipping-point mechanism. Interestingly, the feature helps to produce particular trip (operating) and reset (release) points where contacts will convert the state.
MicroSwitch Terminologies
Here are other terminologies of the microswitch that will help you understand the working principle better:
Differential Travel
This term explains the space between the operating and release points. The idea behind separating these two points is to guard the contacts against fast and unpleasant ON/OFF. And this happens when vibration tries to shorten your switch’s operating life.
Release or Reset Point
At this point, the switch contacts go back to their regular position.
Over-Travel
This safety feature is inside the microswitch. And it helps to stop damage to the switch. It does this by permitting the plunger to travel beyond its operating points.
Also, you have to ensure that the plunger doesn’t exceed its travel distance. Consequently, it will help to reduce damage and mechanical stress.
Trip Point or Operating
The trip point is the area where contacts change their initial state—which is an unoperated position.
Types of Micro Switches
The micro switch types include the following:
Flexible Rod
The flexible rod can rotate in any of the 3600 asides where it runs along the middle of the rod. Further, this switch has a small operating force. But it helps to indicate when there’s inconsistency in the shape or direction. Also, its plunger absorbs the overtravel. Consequently, it offers a large room for operation object play.
Hinge Roller Lever
This switch usually has a roller that attaches to its hinged lever. And it’s ideal for high-speed cam operation.
Rotating Operation
Rotating operations are pretty familiar with low-torque actuators. Hence, this switch is best suited for identifying light objects like paper currency.
Reverse Operation Hinge Roller Lever
Most manufacturers use steel for this lever. The switch uses a reduced torque cam and speed. Plus, it allows you to alter the shape of the level to blend with the operating body.
Spring Short Pin Plunger
Alignment is relatively easy with this switch. And it’s all thanks to its short plunger with a larger diameter. Also, overtravel is enormous.
Leaf Lever
With the leaf lever, you can generate a large stroke. All you need to do is bend the lever. Further, you can use this switch for detecting various moving objects.
Simulated Roller Leaf Lever
This lever is a simple roller type. You can use this switch by bending the leaf lever. While you’re at it, ensure that the end of the device turns into a curve.
Simulated Roller Lever
The simulated lever is yet another simple roller type on this list. You can use it by bending the end of the hinged lever into a curve.
Pin Plunger
The pin plunger is ideal for short, direct strokes. So, you can use it directly to detect high-precision positions. Also, this switch needs a reliable stopper because its overtravel has the shortest actuator.
Leaf Spring
This microswitch has a more significant stroke. And it’s because of the powerful leaf spring. Hence, you can use it for cylinder drives or low-speed cams. Also, it’s vital to maintain the switch’s overtravel within an application’s specification for two significant reasons. First, to avoid damage. Second, it’s because the leaf spring has a fixed bearing point.
Spring Pin Plunger
When you compare the spring pin plunger to a pin plunger, you’ll notice that it has a longer overtravel. However, you can also use this microswitch for the same applications. That said, when you’re using this device, ensure the load is on the plunger’s center. This is because the diameter of the plunger is slightly larger.
Roller Leaf Spring
The difference between the leaf spring and this switch is that it comes with an attached roller. So, you can use it for cam,
Cross or Panel Mounted Roller Pin Plunger
You can operate this device with a camera. Also, it has a roller on its plunger. Even though the overtravel is pretty tiny, you can adjust its position like the panel mount switch.
Hinge Lever
The hinged lever uses a low torque cam and speed. Plus, you can change the lever’s shape to balance the operating body.
Panel Mount Pin Plunger
When you compare this plunger to other types, it has the biggest overtravel. You can mount the switch to a panel with a hexagonal locknut and nut. Then, you can operate it mechanically or manually. Plus, you can use this device alongside a low-speed cam.
Features of MicroSwitches
- Low sensitivity to high accelerations and vibrations
- Compact size
- Boosted service life
- Reduced operating travel
- Increased electrical properties
Advantages of Using a Micro Switch
- It has reliable switching
- The microswitch has a precise function
- The device helps to reduce arcing damage thanks to its fast switching speed.
- Microswitches are ideal for absence and presence detection. And this applies where there’s physical contact with an object.
- It’s also perfect for applications that need easy on-and-off actions
- It has a set of contacts that helps to change the mechanical energy you apply to a plunger in an electrical output.
- The micro switch is best suited if you plan to save weight and space
How to Use a Micro Switch
First, if you leave the circuit in the NC mode (unpressed lever), the LED light that links to the switch’s NC terminal glows. But if you impose a slight push on the lever terminal, the second LED light illuminates. And this happens because there’s contact between the common terminal (C) and NO terminals.
Mounting of Micro Switches
When you’re mounting side micro-switches, ensure you do it on a flat, smooth, and firm surface with the correct screw size. While you’re at it, don’t over-tighten the screws. Also, you can lock the microswitch with epoxy resin for added security.
Micro Switch Applications
- HVAC
- Copy machines
- Microwave oven
- Surveillance systems
- Water heater
Final words
There are different microswitch types. Some of them perform a similar function, while others do different things. So, the one you go for should depend on your project requirements. Also, it’s essential to mount your micro switches appropriately to get the best results.
Do you need help getting the best one for your projects? Please feel free to contact us.