Travel switches can be divided into conventional limit switches, high temperature limit switches and waterproof limit switches according to their functions.
- （1）Conventional travel switch
The conventional travel switch has the advantages of simple structure, practical function and low price, and is favored by the majority of users. - （2）High temperature resistant travel switch
The high temperature limit switch is generally used in steelmaking plants. The high temperature limit switch can work normally in a high temperature environment. The maximum working temperature is 350 degrees. When the temperature of the working environment increases, the life of the product will decrease accordingly. If it exceeds 300 degrees, the workload of the switch should be reduced to ensure the life of the product. The low price and stable performance of this series of travel switches have won unanimous praise from our customers. - （3）Waterproof travel switch
The waterproof travel switch has the characteristics of small size, high sensitivity, strong sealing, oil resistance and corrosion resistance. The most amazing thing is that this kind of travel switch can work in water, which is beyond the reach of similar products.
The travel switch can be divided into direct-acting type, roller type and micro-acting type according to its structure.
1. Direct-acting travel switch
The action principle is similar to the button, the difference is: one is manual, and the other is collided by the collision block of the moving part. When the impact block on the external moving part touches the button to make the contact move, when the moving part leaves, the contact automatically resets under the action of the spring. Its structural principle is shown in Figure F1, and its action principle is the same as that of a button switch, but the opening and closing speed of its contacts depends on the running speed of the production machinery, and it should not be used in places where the speed is lower than 0.4m/min. When the running speed is lower than 0.4m/min, the breaking speed of the contacts will be very slow, and the contacts are vulnerable to arc burning.
2. Roller type travel switch
When the striker on the controlled machine hits the striker rod with the roller, the striker rod turns to the right, drives the cam to rotate, pushes down the push rod, and makes the contacts in the microswitch move quickly. When the moving machine returns, under the action of the return spring, each part of the moving parts is reset.
3. Roller type travel switch
The roller type travel switch is divided into single roller automatic reset and double roller (claw type) non-automatic reset type. The double roller travel switch has two stable positions and has a “memory” function, which can simplify the circuit in some cases.
4. Micro switch type travel switch
The micro-motion limit switch is composed of a push rod, a spring, a compression spring, a dynamic breaking contact and a dynamic closing contact.
