The pressure sensing principle of vacuum pressure switches

The pressure sensing principle of the vacuum pressure switch is mainly based on the deformation of the sensitive element under pressure. Through the mechanical transmission mechanism, the microswitch is triggered to achieve the on-off control of the circuit. The following is a detailed introduction:

Deformation of the sensitive element

The sensitive elements of vacuum pressure switches are usually diaphragms, bellows or pistons, etc. When the pressure in the vacuum system changes, these sensitive components will be subjected to the pressure and undergo corresponding deformations. For example, when the pressure within the system decreases (the vacuum degree increases), the diaphragm will dent towards the vacuum side. When the pressure inside the system rises (the vacuum degree decreases), the diaphragm will bulge in the opposite direction.

Mechanical transmission triggering

The deformation of the sensitive element will be transmitted to the microswitch through the mechanical transmission mechanism. Mechanical transmission mechanisms may include components such as levers and springs, whose function is to amplify the slight deformation of sensitive elements and convert it into mechanical actions that can trigger microswitches. For example, the deformation of the diaphragm will push one end of the lever, and the other end of the lever will exert a force on the microswitch. When the force reaches a certain level, the contacts of the microswitch will act.

Circuit on-off control

The microswitch is a key component of the vacuum pressure switch, which has normally open contacts and normally closed contacts. When the system pressure reaches the set operating pressure value, the contacts of the microswitch will switch, with the normally open contacts closing and the normally closed contacts opening, thereby controlling the on-off of the related circuit. For instance, in vacuum packaging equipment, when the vacuum degree inside the packaging machine reaches the set value, the contacts of the vacuum pressure switch close, connecting the control circuit and causing the packaging machine to stop vacuuming and enter the next working stage. When the vacuum degree inside the packaging machine drops to a certain extent, the contacts of the vacuum pressure switch open, cutting off the control circuit and triggering an alarm or starting the backup vacuum extraction equipment.