Position switches in printing machines
S970 microswitches are used in position and access control systems on printing machines. They are resistant to aggressive cleaning agents and powder dust.
S970 snap-action switches are used in printing and coating units on sheet-fed offset printing machines, for example at Heidelberger Druckmaschinen AG. To dry the printed sheets, a powder dust is used, which is also chemically aggressive.
What tasks do the microswitches perform?
S970 snap-action switches function as position switches in the printing and coating units. They are used to detect the positions of the rollers and their movement state.
The snap-action switches are also used for plant safety, to check the position of the levers that allow the printing machine to be opened. If the operator moves a lever while the machine is running, the snap-action switch is actuated and the controller stops the machine.
Why was the S970 chosen?
The S970 has a polyetherimide housing that is impervious to powder dust. It is also resistant to the particularly aggressive cleaning agents. The S970 is a special version of the S870 snap-action switch with the following features:
- Compact and robust design, high shock and vibration resistance
- Positive opening operation of the break contact (VDE approved)
- Suitable for safety-relevant applications (Machinery Directive, ISO EN 13849)
- Self-cleaning contacts
- Protection class up to IP67 with leads
