In all cases where the vacuum is involved, for a smooth exchange between the vacuum pump and the air supply in the circuit, there is a need for solenoid valves that can create vacuum and restore atmospheric pressure when needed and that prove reliable in various fields and eventualities. Even in the event of a sudden blackout.
Vuototecnica’s 3/2 bistable solenoid valves were designed to maintain their switching position even in the event of a power outage and are therefore an excellent safety shield to always maintain the vacuum level in the suction cups when needed, avoiding load losses.
Three families of 3/2 bistable solenoid valves are available in Vuototecnica catalogue.
The series 07..51 is special because, in addition to maintaining the switching position in the event of a power failure, it can also do so in the event that the automatic servopilot is depressurized (e.g. if the compressed air supply hose of the pilot is accidentally cut off). The valve would remain in the last selected position (switched open or closed).
Especially in some applications it is essential that this is the case. Think, for example, of loads suspended from suction cups and the damage that would occur if the load were to be let go at some point.
Vuototecnica thought of everything: bistable solenoid valves can guarantee the maintenance of vacuum inside suction cups, keeping them in communication with the vacuum tank of an electric depressor or of a pneumatic depressor.
A good alternative to this first family of solenoid valves is the
07….53 series. They are also pneumatically piloted solenoid valves but the principle of bistability is guaranteed by the low absorption pneumatic pilot valve thanks to which the solenoid valve changes position, open or closed, only when it receives an electric signal with inverse polarity to the initial one (e.g. positive/negative to open; negative/positive to close). The result on the load in the absence of electricity is the same, but in this case it is a more compact solution, which does not need a double pilot coil, and therefore can be useful in particular cases where there is not much space available.
Finally, the 07..63 series uses the same operating principle as the previous series, with an electrical signal with reversed polarity, but the solenoid valves in this family do not need compressed air to be piloted. They are servo-assisted by vacuum, that is, they are driven by the vacuum generated by the suction pump, in complete safety. They are therefore extremely useful when it is not possible to guarantee compressed air for piloting, for example on loaders or unloaders with suction cups.
All Vuototecnica solenoid valves are built with quality materials, made to last, and it is always possible to request the advice of Vuototecnica designers to know which series is most suitable for a certain type of application.
To learn more about the world of Vuototecnica valves and solenoid valves, download Vacuum Solution catalogue at www.vuototecnica.net