Patent ID: 9108379
Filing Date: 2015-08-18
Classification: B30B

Abstract:
1. A tandem press line comprising: a control system including a controller, the control system being configured to supply a line master control signal, an individual press control signal that corresponds to and is synchronized with the line master control signal and an individual transfer control signal that corresponds to and is synchronized with the line master control signal; a plurality of presses that perform a synchronized press control for each of the plurality of presses by using the individual press control signal; and a plurality of transfer systems that are alternately disposed with the plurality of presses in a line direction, and perform a synchronized transfer control for each of the plurality of transfer systems by using the individual transfer control signal, wherein the controller is configured to: perform a synchronized low-speed press control for each of the plurality of presses by using a low-speed individual press control signal that corresponds to and is synchronized with a low-speed line master control signal when the line master control signal has been switched from a high-speed line master control signal to the low-speed line master control signal; determine whether or not a slide position of each of the plurality of presses under the synchronized low-speed press control is within a press region; switch the synchronized low-speed press control to a non-synchronized high-speed press control using a non-synchronized high-speed individual press control signal that is not synchronized with the low-speed line master control signal for a press among the plurality of presses having a slide position that has been determined to be within the press region at least during a period in which the slide position is within the press region; stop the non-synchronized high-speed press control on condition that the slide position under the non-synchronized high-speed press control has reached a press resynchronization point; and switch the non-synchronized high-speed individual press control signal to the low-speed individual press control signal for resynchronization, and automatically switch the non-synchronized high-speed press control that has been stopped to the synchronized low-speed press control on condition that a phase of the low-speed line master control signal has become equal to a phase of the non-synchronized high-speed individual press control signal.