Press line system and method

Abstract

An press line including at least one mechanical press with at least one electric drive motor, a ram, a mechanical unit for operating the press, and one other device or auxiliary production device. The press is arranged so that the speed of the at least one said drive motor may be varied during at least one pressing or non-pressing part of a press cycle. Improved operating characteristics and optimised energy use and cycle times are obtained by controlling the speed of the motor and synchronizing a movement of the press to a movement or position of at least other device, loader or other press. A system includes the press. A computer program controlls the press line.

1 . A method for operating a press line comprising at least one mechanical press with at least one electric drive motor, a ram, a mechanical element for operating said press, and one other device in a press line, the method comprising:
 varying a speed of the at least one electric drive motor during at least one pressing or non-pressing part of a press cycle; and   controlling said motor such that a movement of said press may be synchronized to a movement or position of at least one said other device in said press line.   
   
   
       2 . The method according to  claim 1 , further comprising:
 controlling said other device during the at least one pressing or non-pressing a part of a press cycle and synchronizing the movement of said other device to a movement or position of said press, another device which may be another press in said press line.   
   
   
       3 . The method according to  claim 1 , further comprising:
 controlling said press and synchronizing a movement of said press or said other device during the at least one pressing or non-pressing a part of a press cycle wherein said press and said another device are either slave to device or free.   
   
   
       4 . The A method according to  claim 1 , further comprising:
 controlling said other device and synchronizing to a movement of a device which may be said press, another press or any other device in said line during a first part of a press cycle and synchronizing to a movement of a different device during a second part of the press cycle.   
   
   
       5 . The method according to  claim 1 , further comprising:
 controlling said other device in order to synchronize to a movement or position of a device downstream of said other device in said press line during a first part of a press cycle; and   controlling the movement of said other device in order to synchronize movement of the other device to a movement or position of a device upstream of said other device in said press line during a second part of the press cycle.   
   
   
       6 . The method according to  claim 1 , further comprising:
 controlling said other device in order to operate as fast as possible during a first part of a press cycle and by controlling the movement of said press in order to operate the press as fast as possible in a second part of the press cycle.   
   
   
       7 . The method according to  claim 1 , further comprising:
 calculating a prediction of when a device will reach a certain point in a part of the press cycle.   
   
   
       8 . The method according to  claim 7 , further comprising:
 supplying the prediction to another device or to a controller.   
   
   
       9 . The method according to  claim 1 , further comprising:
 synchronizing the unloader device or robot during at least one part of a press cycle as a slave to said press,   synchronizing the loader device or robot as a slave to the unloader device or robot, and   synchronizing said press as a slave to the loader device or robot.   
   
   
       10 . The method according to  claim 1 , wherein said other device may be any from the group of: a loader, an unloader, a robot, another press. 
   
   
       11 . The method according to  claim 1 , wherein said other device is at least one loader device or at least one robot arranged to load said press. 
   
   
       12 . The method according to  claim 1 , wherein said other device is at least one unloader device or at least one robot arranged to unload said press. 
   
   
       13 . The method according to  claim 9 , wherein the loader or unloader device or robot arranged to load, respective unload said press is also arranged as an unloader, respective loader of another press. 
   
   
       14 . The method according to  claim 9 , wherein the loader and/or unloader device is arranged as two devices or robots working together to load and/or unload as a pair. 
   
   
       15 . The method according to  claim 14 , wherein the first one of the two devices or robots working together is controlled synchronised as a slave to the second device or robot of the pair. 
   
   
       16 . The method according to  claim 1 , wherein a robot control unit calculates a path for a robot, and calculates a motion or position for a press and sends control values for synchronised movement to a control unit or drive unit of a press. 
   
   
       17 . The method according to  claim 1 , wherein a robot control unit calculates a path for a robot, and calculates motion setpoint values for a press and sends torque and/or speed and/or position setpoint values to a control unit or drive unit of a press. 
   
   
       18 . The method according to  claim 1 , further comprising:
 controlling the speed of said at least one electric drive motor in order to optimise at least one press cycle of said press.   
   
   
       19 . The method according to  claim 1 , further comprising:
 controlling the speed of a said at least one electric drive motor; and   optimising said press line dependent on parameters from the group of: a state of a downstream process; a state of an upstream process; overall power or energy consumption; smoothing of power consumption peaks.   
   
   
       20 . The method according to  claim 1 , further comprising:
 controlling the speed of said at least one electric drive motor during at least one part of a press cycle to wait or operate more slowly or with reduced power demand or energy consumption while keeping within a target time for the press cycle as a whole.   
   
   
       21 . The method according to  claim 1 , wherein the speed of a said at least one electric drive motor during the at least one pressing or non-pressing part of a press cycle of said press is controlled to vary and is greater than the speed of said drive motor during a pressing part of the press cycle. 
   
   
       22 . The method according to  claim 1 , wherein said press cycle may be carried out in said first rotation direction of a production cycle and extend over more than 360 degrees of crank angle or eccentric rotation. 
   
   
       23 . The method according to  claim 1 , wherein a said press cycle is carried out in said first rotation direction and comprises a step of reversing said drive motor at the end of each complete press cycle and operating in a second rotational direction. 
   
   
       24 . The method according to  claim 1 , wherein the speed of said drive motor is maintained at a high or maximum speed greater than the motor speed during pressing for a period of time. 
   
   
       25 . The method according to  claim 24 , wherein the speed of said drive motor is reduced from a pressing speed and may approach a zero speed for a period of time during the pressing part of said press cycle. 
   
   
       26 . The method according to  claim 25 , further comprising:
 providing a control output to said drive control means wherein said motor is decelerated and the press maintained at a standstill upon reaching bottom dead center, or thereabouts, for a period of time.   
   
   
       27 . The method according to  claim 1 , further comprising:
 providing a control output to said drive control means of the second drive motor to move said ram to a cycle start position for each press cycle which is a plurality of degrees of crank angle backwards in a second rotation direction from the previous prior press cycle stop position or zero-speed position.   
   
   
       28 . The method according to  claim 23 , wherein said press reverses from the first rotation direction to the second rotation direction over a plurality of degrees between the stop of a first press cycle and the start of a second press cycle. 
   
   
       29 . The method according to  claim 1 , wherein said motor is controlled such that said motor rotational motion reverses direction from the first rotation direction to a second and opposite rotation direction between each successive and complete press cycle. 
   
   
       30 . The method according to  claim 1 , wherein the at least one motor is decelerated to a reduced speed or a zero speed by means in part of regenerative braking. 
   
   
       31 . The method according to  claim 1 , wherein the drive motor speed is variably controlled to slow the press down upon reaching Unload Cam or thereabouts for a period of time for synchronization purposes and re-accelerate the press before reaching the Die Protect position or thereabouts of the next press cycle. 
   
   
       32 . The method according to  claim 1 , wherein said press line includes at least one press which comprises a second drive motor or actuator arranged connected to said ram such that by providing a control output to a drive control means of said second drive motor the speed of said second drive motor is varied during at least one part of a press cycle. 
   
   
       33 . The method according to  claim 1 , wherein the speed or position of the second drive motor is controlled to synchronize to a speed or position of the flywheel or the first drive motor of said press prior to and/or while engaging a clutch of said press. 
   
   
       34 . The method according to  claim 1 , wherein the clutch operation is synchronised to a movement or position of said press or to second motor of said press. 
   
   
       35 . The method according to  claim 1 , wherein the first or flywheel motor is controlled to optimise or minimise for said press or said press line any from the group of: peak power consumption, energy consumption, cycle time, any combination. 
   
   
       36 . A system, comprising:
 a press line including at least one mechanical press with at least one electric drive motor   a ram,   a mechanical means for operating said press, and   one other device in a press line,   wherein said press of said system is arranged so that the speed of the at least one drive motor may be varied during at least one pressing or non-pressing part of a press cycle and/or that the speed of said motor may be controlled in order to synchronize a movement of said press to a movement or position of at least one said other device in said press line.   
   
   
       37 . The system according to  claim 36 , further comprising:
 a control configured to control said other device during a first part of a press cycle and synchronizing the movement of the said other device to a movement or position of said press, another device which may be another press in said press line.   
   
   
       38 . The system according to  claim 36 , wherein a loader or loader robot is the at least one other device and said press is controlled to synchronize to a movement of the loader or loader robot during a first part of a press cycle. 
   
   
       39 . The system according to  claim 36 , further comprising:
 a control configured to control said other device and synchronizing to a movement or position of a device which may be said press, another press or any other device in said press line during a first part of a press cycle and controlling the movement of said press and synchronizing to a movement or position of a different device during a second part of the press cycle.   
   
   
       40 . The system according to  claim 36 , further comprising:
 controlling the said other device in order to synchronize to a movement or position of a downstream device which may be said press, another press or any other device in said press line during a first part of a press cycle and controlling the movement of the said other device in order to synchronize it to a movement or position of a different device upstream of said other device during a second part of the press cycle.   
   
   
       41 . The system according to  claim 36 , further comprising:
 controlling one first device in said press line synchronised to a second device in said press line by a method of constant motion following.   
   
   
       42 . The system according to  claim 36 , further comprising:
 controlling one first device in said press line synchronised to a second device in said press line by a method of synchronising to a point or position, for devices.   
   
   
       43 . The system according to  claim 36 , further comprising:
 a calculation unit configured to calculate a prediction of when a device will reach a certain point in a part of the press cycle.   
   
   
       44 . The system according to  claim 43 , further comprising
 a supply unit configured to supply the prediction of when the device will each the certain point to another device or to a controller.   
   
   
       45 . The system according to  claim 36 , further comprising:
 a robot control unit comprising a calculating unit configured to calculate a path for a robot, and to calculate a movement or position for a press and a sending unit configured to send control values for synchronised movement based on the calculations to a control unit or drive unit of a press.   
   
   
       46 . The system according to  claim 36 , further comprising:
 a robot control unit a calculating unit configured to calculate a path for a robot, and to calculate motion setpoint values for a press, and a sending unit configured to send torque and/or speed and/or position setpoint values to a control unit or drive unit of the press.   
   
   
       47 . The system according to  claim 36 , further comprising:
 a control configured to control means for controlling said press such that the press is reversible from a first rotation direction to a second rotation direction over a plurality of degrees between the stop of a first press cycle and the start of a second press cycle.   
   
   
       48 . The system according to  claim 36 , further comprising:
 a control configured to control said press such that said press cycle may be carried out in said first rotation direction and comprise a step of reversing said drive motor at the end of each complete press cycle and operating in a second rotational direction.   
   
   
       49 . The system according to  claim 36 , further comprising:
 an energy or power management unit comprising a power limiter arrangement to limit the total power or peak power of the total consumption of the flywheel motor and the auxiliary second motor.   
   
   
       50 . The system according to  claim 36 , wherein said press is arranged controlled by at least two processors or CPUs of which one processor controls the safety devices and the second processor controls the remainder of the devices. 
   
   
       51 . The system according to  claim 36 , wherein a motor drive of said press is controlled by the control processor or CPU and is used to accelerate the press from one speed to another speed. 
   
   
       52 . The system according to  claim 36 , wherein the at least two processors or CPUs are arranged connected in the system by industrial field buses. 
   
   
       53 . The system according to  claim 36 , wherein said press line comprises one of a plurality of press lines. 
   
   
       54 . The system according to  claim 36 , wherein a controller for press motion and/or device motion comprises a calculating unit configured to carry out calculations for synchronisation in the press line. 
   
   
       55 . The system according to  claim 36 , wherein a controller for said press line comprises a calculating unit configured to carry out calculations for synchronisation in the press line. 
   
   
       56 . The system according to  claim 30 , wherein said press line is arranged with at least one electrical power supply device comprising at least one rectifier arranged to supply power simultaneously for more than one electrical motor comprised in said press, another press or other device of said press line. 
   
   
       57 . The system according to  claim 56 , wherein the at least one electrical power supply for said press line may comprise any device from the group of: single rectifier, single DC-link, multiple inverters. 
   
   
       58 . The system according to  claim 57 , wherein an electrical electrical power supply device of the at least one electrical power supply is arranged to supply power to said press comprising more than one electrical motor. 
   
   
       59 . The system according to  claim 36 , wherein said at least one mechanical press comprises a mechanical unit configured to operated the press comprising any transmission type from the group of: crank, knuckle, link, cam, screw, ball screw, rack-type mechanism. 
   
   
       60 . The system according to  claim 36 , wherein said at least one mechanical press comprises means for measuring a speed and/or position of at least one said drive motor. 
   
   
       61 . The system according to  claim 36 , further comprising:
 at least one said mechanical press comprising at least one second or auxiliary drive motor also arranged to drive said press.   
   
   
       62 . The system according to  claim 36 , wherein further comprising:
 an energy recovery unit or storage configured to recover energy in said press synchronised and/or optimised to minimize a peak power consumption of said press line.   
   
   
       63 . The system according to  claim 36 , further comprising:
 an energy recovery unit or storage configured to recover energy in said press synchronised and/or optimised so as to minimize an energy consumption of said press line.   
   
   
       64 . The system according to  claim 36 , wherein one or more motors are controlled to synchronise a movement of said press to one or more of the at least one said other device(s) such that one first motor is not always mechanically coupled to said press and where the a second motor is always mechanically coupled to said press. 
   
   
       65 . A computer program product, comprising:
 a computer readable medium; and   computer program instructions recorded on the computer readable medium and executable by a processor carrying out a method for operating a press line comprising at least one mechanical press with at least one electric drive motor, a ram, a mechanical unit configured to operate said press, and one other device in a press line, the method comprising varying the at least one electric drive motor during at least one said pressing or non-pressing part of a said press cycle.   
   
   
       66 . (canceled) 
   
   
       67 . The method according to  claim 1 , wherein the press line is operated for single stroke, continuous operation or both for any operation on metal blanks or workpieces from the group of: pressing, bending, stamping, hot stamping, deep drawing, cutting, notching, blanking, minting, punching. 
   
   
       68 . The system according to  claim 36 , wherein the system is configured for single stroke or continuous operation or both for an operation on a material comprising a plastic from any of the group of: pressing, moulding, compression moulding, reaction moulding, reaction injection moulding, blow moulding, dough moulding, injection moulding, thermoplastic moulding.