Patent attributes
A method for controlling a vacuum generator (3) in a vacuum system (10) for transportation of objects, which vacuum system (10) comprises a vacuum generator (3) driven by a compressed air flow via a first on/off valve (1), wherein the vacuum generator (3) is arranged to be brought in flow connection with the vacuum gripper means (6) comprised in the vacuum system (10), in order to supply vacuum to the vacuum gripper means (6) in result of the compressed air flow, wherein the vacuum system (10) comprises a second valve (2), which is arranged to supply compressed air into the vacuum system (10); one centralized pressure sensor (4) used for monitoring a system pressure (P) inside the vacuum system (10) and for adaptive blow-off; and a vacuum system controller (5), wherein if the on/off valve (1) is not flowing air to the vacuum generator (3), the vacuum system controller (5) indicates a state of no vacuum generation, and the second valve (2) is activated, allowing an amount of compressed air to flow into the vacuum-system (10) for blow-off, using vacuum system properties being characterized with respect to volume and flow-restriction in relation to the blow-off capacity of the blow-off function and for every release cycle wherein blow-off is terminated and excessive air injected into the system is released through the vacuum gripper means, analyzing pressure propagation following blow-off for calculating a duration of when the vacuum system (10) is being fully pressure-equalized (E) in parts of the vacuum gripper means by using a compensation factor (k), wherein the compensation factor (k) is stored and used for the next release cycle.
