Control system, press machine, and control method for press machine

Patent metadata

Field	Value
Publication number	US-10576705-B2
Application number	US-201515329321-A
Country	US
Kind code	B2
Filing date	Jul 31, 2015
Priority date	Aug 19, 2014
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

A control system includes a load detector, a determination unit, and a drive control unit. The load detector detects a load of a slide. The load of the slide includes a positive load due to a pressing force of the slide during pressing and a negative load at the time of a breakthrough. The determination unit determines whether to execute emergency stopping of the slide based on the positive load and the negative load detected by the load detector. The drive control unit controls the driving of the slide based on the determination result of the determination unit.

First claim

What is claimed is:

1. A control system for a press machine which raises and lowers a slide to perform pressing, the control system comprising:
a load detector arranged to detect a load of the slide including a positive load due to a pressing force of the slide during pressing and a negative load occurring at a breakthrough, the negative load being oriented in a direction opposite a direction of the positive load; and
a controller arranged to receive a detection signal from the load detector indicating the positive load and the negative load,
the controller being configured perform an emergency stop determination to determine whether to execute an emergency stop of the slide based on the positive load and the negative load,
the controller using a correction coefficient to obtain a corrected detection value of the load and determining whether to execute the emergency stop based on the corrected detection value when the load detected by the load detector is a negative load, and
the controller being configured to control driving of the slide based on a determination result of the emergency stop determination.

2. The control system for a press machine according to claim 1 , wherein
the controller performing the emergency stop determination by performing an overload determination in which the controller decides to execute the emergency stop when a maximum value of the positive load is greater than a predetermined first overload determination value.

3. A control system for a press machine which raises and lowers a slide to perform pressing, the control system comprising:
a load detector arranged to detect a load of the slide including a positive load due to a pressing force of the slide during pressing and a negative load occurring at a breakthrough, the negative load being oriented in a direction opposite a direction of the positive load; and
a controller arranged to receive a detection signal from the load detector indicating the positive load and the negative load,
the controller being configured perform an emergency stop determination to determine whether to execute an emergency stop of the slide based on the positive load and the negative load,
the controller performing the emergency stop determination by performing an overload determination in which the controller decides to execute the emergency stop when an absolute value of a minimum value of the negative load is greater than a predetermined second overload determination value, and
the controller being configured to control driving of the slide based on a determination result of the emergency stop determination.

4. A control system for a press machine which raises and lowers a slide to perform pressing, the control system comprising:
a load detector arranged to detect a load of the slide including a positive load due to a pressing force of the slide during pressing and a negative load occurring at a breakthrough, the negative load being oriented in a direction opposite a direction of the positive load; and
a controller arranged to receive a detection signal from the load detector indicating the positive load and the negative load,
the controller being configured perform an emergency stop determination to determine whether to execute an emergency stop of the slide based on the positive load and the negative load,
the controller performing the emergency stop determination by performing an overload determination in which the controller decides to execute the emergency stop when a difference between a maximum value of the positive load and a minimum value of the negative load is greater than a predetermined third overload determination value, and
the controller being configured to control driving of the slide based on a determination result of the emergency stop determination.

5. The control system for a press machine according to claim 2 , wherein
the controller promptly stops the slide when the controller decides to execute the emergency stop in the overload determination.

6. The control system for a press machine according to claim 1 , wherein
the controller performing the emergency stop determination by performing a load lower limit determination in which the controller decides to execute the emergency stop when a maximum value of the positive load is less than a predetermined first lower limit determination value.

7. A control system for a press machine which raises and lowers a slide to perform pressing, the control system comprising:
a load detector arranged to detect a load of the slide including a positive load due to a pressing force of the slide during pressing and a negative load occurring at a breakthrough, the negative load being oriented in a direction opposite a direction of the positive load; and
a controller arranged to receive a detection signal from the load detector indicating the positive load and the negative load,
the controller being configured perform an emergency stop determination to determine whether to execute an emergency stop of the slide based on the positive load and the negative load,
the controller performing the emergency stop determination by performing a load lower limit determination in which the controller decides to execute the emergency stop when an absolute value of a minimum value of the negative load is less than an absolute value of a predetermined second lower limit determination value,
the controller being configured to control driving of the slide based on a determination result of the emergency stop determination.

8. A control system for a press machine which raises and lowers a slide to perform pressing, the control system comprising:
a load detector arranged to detect a load of the slide including a positive load due to a pressing force of the slide during pressing and a negative load occurring at a breakthrough, the negative load being oriented in a direction opposite a direction of the positive load; and
a controller arranged to receive a detection signal from the load detector indicating the positive load and the negative load,
the controller being configured perform an emergency stop determination to determine whether to execute an emergency stop of the slide based on the positive load and the negative load,
the controller performing the emergency stop determination by performing a load lower limit determination in which the controller decides to execute the emergency stop when a difference between a maximum value of the positive load and a minimum value of the negative load is less than a predetermined third lower limit determination value,
the controller being configured to control driving of the slide based on a determination result of the emergency stop determination.

9. The control system for a press machine according to claim 6 , wherein
the controller moves the slide to a predetermined standby position and stops the slide when the controller executes the emergency stop in the load lower limit determination.

10. The control system for a press machine according to claim 1 , further comprising
a display configured to display the positive load and the negative load detected by the load detector.

11. The control system for a press machine according to claim 10 , wherein
the load detector includes a first load detector arranged to detect a left load on a left side of the slide and a second load detector arranged to detect a right load on a right side of the slide, and
the display displays the left and right loads and a total of the left and right loads.

12. The control system for a press machine according to claim 10 , wherein
the display displays a waveform indicating changes in the loads of the slide including the positive load a

Assignees

• Komatsu Ind Corp

Inventors

• Takeuchi Hisanori

Classifications

• B30B15/26

  Program-control arrangements · CPC title

• B30B15/281 Primary

  overload limiting devices (in general F16H35/10) · CPC title

• B30B15/148

  Electrical control arrangements · CPC title

• B30B15/0094

  Press load monitoring means (B30B15/281 takes precedence) · CPC title