What Is a Push Switch?

Self-locking switch is a common push button switch. When the switch button is pressed for the first time, the switch is turned on and held, which is self-locking. When the switch button is pressed for the second time, the switch is turned off, and at the same time, the switch button pops up.

Self-locking switch

Self-locking switch is a common push button switch. When the switch button is pressed for the first time, the switch is turned on and held, which is self-locking. When the switch button is pressed for the second time, the switch is turned off, and at the same time, the switch button pops up.

Chinese name

Self-locking switch

Operating temperature range

-40 70

Withstand pressure

AC 250V (50Hz) / min

Contact

100M

The self-locking switch generally refers to the switch with its own mechanical lock function. When you press it, the button will not jump up completely when you release it. In the locked state, you need to press it again to unlock it completely. It's called a self-locking switch. Early televisions and monitors that were completely powered off were such switches.

The difference between a self-locking switch with a light and a common self-locking switch is that the lighted switch makes full use of the space in its keys to place a small indicating bulb or LED, one end of which is connected to the neutral wire, and the other end is generally connected through a The piezoresistor is connected in parallel with the normally open contact of the switch. When the switch is closed, the device also provides power for the indicator at the same time. Its types include diagonal simultaneous switching, parallel simultaneous switching, and straddle simultaneous switching.

In fact, the self-locking switch and the tactile switch describe the performance of the switch from different aspects; "self-locking" means that the switch can maintain a certain state (on or off) through the locking mechanism. "Tap" means that the switch is used Strength.

Self-locking switch

In general, mechanical switches may be distinguished as follows:

From the operation mode, the switches are divided into knob type, plate type (including button switch, boat switch), and button type; most of the knob type and plate type switch can be maintained (locked) in the on or off state after operation. For example, the daily use of the light switch, fan speed switch, most of these switches do not need to emphasize the self-locking, because there are obvious "operating directions"; only push-button switches, when used, are pushed, most push-button switches Both are used to turn on or off the circuit when pressed. The state is restored after release, so it is sometimes called an "electric bell switch". In order to achieve the state of being "pressed", a push-button switch is added like an ordinary switch. There is a self-locking device, which uses the self-locking performance to keep it on or off by itself. This is a switch with a self-locking. Among them, for some needs, only one of the switches is allowed to be connected during operation. State, when the rest must be disconnected, there are several push button switches combined side by side, and the "interlock mechanism" is used, only one of the switches is allowed to be in the connection locked state. When the other switch is pressed, When the switch is locked, but the original lock switch is released (e.g., "play, fast forward, rewind" button on mechanical tape recorder). These switches can have one or more contacts; there are also many locking mechanisms. Among them, a spring hook is used to slide along a heart-shaped groove. The two tips of the heart-shaped groove correspond to the lock and release positions of the switch.

As the name implies, "tap" means that the state of the switch contact can be changed without touching it with much force, so the contact capacity is small and the structure is simple. After the switch force is removed, it can only maintain the original state. Single-button pushbutton switches without locking can be pressed with a small amount of force. At present, membrane switches and small micro-switches can be considered as touch switches. Most of the structures are printed with conductive lines on two mutually insulated films. Connect the wires to each other; or use butterfly springs made of thin elastic metal to press the springs to connect the printed circuits.

The switches on the rice cooker and the electric kettle are locked after being pressed, but after heating to the specified conditions, the magnet or bimetal that locks the switch is activated to reset the switch and cut off the power at the same time (the rice cooker is switched to the thermal insulation state) May not meet the "reset after power off" requirement.

Reset after power failure, that is, the locking mechanism should be related to the power supply. The finished product does not seem to be, because this requirement can be achieved by using a circuit composed of a general push button switch and a relay; but if only one relay (or contactor) is used, The group of normally open contacts is used to control the power supply of the working coil of the relay (contactor). The relay weighing iron is used as the switch button. After pressing the weighing iron, the relay control coil contacts are closed, the coil is energized, and the relay remains closed ( Self-locking), the remaining contacts control other lines; once the power is cut off, the relay will be cut off immediately, the weighing iron will be reset, and the equivalent button will be reset. You need to press the relay weighing iron again to turn on the power again. This relay is now a push-button switch with electrical lock.

As for infrared switches, IC card switches, and other switches with other components, they are no longer in the scope of mechanical switches and cannot be considered mechanical switches.