Electric Service Load Management

• US 20080193584A1
• Filed: 02/13/2007
• Published: 08/14/2008
• Est. Priority Date: 02/13/2007
• Status: Active Grant

• Current Assignee: Husky Injection Molding Systems Limited
• Original Assignee: Husky Injection Molding Systems Limited
• Inventors: Cooke, Gregory Michael
• Granted Patent: US 7,568,905 B2
• Time in Patent Office: Days
• US Class Current: 425/143
• CPC Class Codes: B29C 2945/76033 Electric current or voltage
• CPC Class Codes: B29C 2945/76177 Location of measurement
• CPC Class Codes: B29C 2945/76525 Electric current or voltage
• CPC Class Codes: B29C 2945/76943 compare with thresholds
• CPC Class Codes: B29C 45/7666 of power or energy, e.g. integral function of force

Abstract

The electric service load of a machine having at least one electric heater and at least one electric motor may be managed as follows. Where the electrical service load of the machine exceeds a threshold, which may result from transient in-rush current attendant upon start-up of an electric motor, or where this load is expected to exceed the threshold, at least one of the heaters may be de-energized. The heater may remain de-energized either for a pre-determined period of time or until the electrical service load falls below a further threshold.

Claims

1. A method of managing electric service loads of a molding system, comprising:

energising a first electrically powered system component;

energising a second electrically powered system component;

where (i) said electrical service load exceeds a threshold, or (ii) said electrical service load is expected to exceed said threshold, at least partially de-energising said first electrically powered system component.

2. The method of claim 1 including partially de-energising said first electrically powered system component either (a) for a pre-determined period of time or (b) until said electrical service load falls below a further threshold.

3. The method of claim 1 wherein said first electrically powered system component is an electric heater and said second electrically powered system component is an electric motor and where said heater is at least partially de-energised during in-rush current consequent upon energising said electric motor.

4. The method of claim 3 wherein said heater is de-energized for a pre-determined period of time.

5. The method of claim 3 wherein said heater is de-energized until current to said molding system falls below a further threshold.

6. The method of claim 3 wherein said molding system comprises an injection molding machine, said electric motor is an hydraulic pump motor and said heater is one of a barrel heater and a mold heater.

7. The method of claim 3 wherein said heater is a first heater and further comprising at least partially de-energising a second heater during in-rush current consequent upon energising said electric motor.

8. The method of claim 7 wherein said molding system comprises an injection molding machine, said electric motor is an hydraulic pump motor, said first heater is a barrel heater and said second heater is a mold heater.

9. The method of claim 7 wherein said at least partially de-energising said barrel heater comprises suspending power to said barrel heater and wherein said at least partially de-energising said mold heater comprises suspending power to said mold heater.

10. The method of claim 1 wherein said at least partially de-energising said first electrically powered system component comprises suspending power to said first electrically powered system component.

11. The method of claim 1 wherein said molding system is at least one of a molding machine and an auxiliary equipment of said molding machine.

12. The method of claim 11 wherein said auxiliary equipment includes at least one of:

a coolant chiller, a dehumidifier, a compressor, a robot, a conveyor, and/or a resin dryer, and any combination or permutation thereof.

13. The method of claim 11 wherein said first electrically powered system component and said second electrically powered system component are configured in said molding machine.

14. The method of claim 11 wherein said first electrically powered system component and said second electrically powered system component are configured in said auxiliary equipment.

15. The method of claim 11 wherein said first electrically powered system component is configured in one of said molding machine and said auxiliary equipment and said second electrically powered system component is configured in the other of said molding machine and said auxiliary equipment.

16. A molding system, comprising:

a first electrically powered system component;

a second electrically powered system component;

a machine controller for selectively controlling current to said first electrically powered system component and said second electrically powered system component, said machine controller operable to;

energize said first electrically powered system component;

energize one second electrically powered system component;

where (i) said electrical service load exceeds a threshold, or (ii) said electrical service load is expected to exceed a threshold, at least partially de-energize said first electrically powered system component.

17. The molding system of claim 16 wherein said machine controller configured to at least partially de-energize said first electrically powered system component either (a) for a pre-determined period of time or (b) until said electrical service load falls below a further threshold.

18. The molding system of claim 16 wherein said first electrically powered system component is an electric heater and said second electrically powered system component is an electric motor.

19. The molding system of claim 16 wherein said molding system is at least one of a molding machine and an auxiliary equipment of said molding machine.

20. The molding system of claim 19 wherein said auxiliary equipment includes at least one of:

a coolant chiller, a dehumidifier, a compressor, a robot, a conveyor, and/or a resin dryer, and any combination or permutation thereof.

21. The molding system of claim 19 wherein said first electrically powered system component and said second electrically powered system component are configured in said molding machine.

22. The molding system of claim 19 wherein said first electrically powered system component and said second electrically powered system component are configured in said auxiliary equipment.

23. The molding system of claim 19 wherein said first electrically powered system component is configured in one of said molding machine and said auxiliary equipment and said second electrically powered system component is configured in the other of said molding machine and said auxiliary equipment.

24. The molding system of claim 19 wherein said auxiliary equipment includes an auxiliary controller connectable to said machine controller, said auxiliary controller configured to cooperate with said machine controller for selectively controlling current to said first electrically powered system component and said second electrically powered system component.

25. An injection molding machine, comprising:

a cold mold half;

a hot mold half having runners for porting melt into a mold cavity formed between said hot mold half and said cold mold half;

a hot mold electric heater for heating said hot mold half proximate said runners;

an hydraulic cylinder for pressing said hot mold half and said cold mold half together;

an electrical pump motor for pumping hydraulic fluid in said hydraulic cylinder;

an injection unit for containing melt for injection into said mold cavity;

an injection unit electric heater for heating said injection unit;

a machine controller for selectively switching current to said hot mold electric heater, said injection unit electric heater, and said electric pump motor, said machine controller operable to;

energize said hot mold electric heater and said injection unit electric heater to bring said injection unit and said hot mold half to a working temperature;

de-energize, at least partially, at least one of said hot mold electric heater and said injection unit electric heater during a transient peak current requirement of said electrical pump motor;

re-energize said at least one of said hot mold electric heater and said injection unit electric heater after subsidence of said transient peak current requirement to said electrical pump motor.

26. The machine of claim 25 wherein said machine controller is operable to suspend power to said at least one of said hot mold electric heater and said injection unit electric heater during a transient peak current requirement of said electrical pump motor.

27. A computer readable media containing computer executable instructions which, when executed by a machine controller in a molding system, cause said machine controller to:

send a first control signal to energize a first electrically powered system component of a machine controlled by said machine controller;

send a second control signal to energize a second electrically powered system component of said machine;

where an electrical service load of said first electrically powered system component and said second electrically powered system component either (i) exceeds a threshold or (ii) is expected to exceed a threshold, send a third control signal to de-energize, at least partially, said first electrically powered system component.

28. The computer readable media of claim 27 wherein said third control signal is for partially de-energising said first electrically powered system component either (a) for a pre-determined period of time or (b) until said electrical service load falls below a further threshold.

29. The computer readable media of claim 28 wherein said first electrically powered system component is an electric heater and said second electrically powered system component is an electric motor and where third control signal is operable to at least partially de-energize said heater during in-rush current consequent upon energising said electric motor.

30. The computer readable media of claim 29 wherein said heater is de-energized for a pre-determined period of time.

31. The computer readable media of claim 29 wherein said heater is de-energized until current to said molding system falls below a threshold.

32. The computer readable media of claim 29 wherein said molding system comprises an injection molding machine, said electric motor is an hydraulic pump motor and said heater is one of a barrel heater and a mold heater.

33. The computer readable media of claim 29 wherein said heater is a first heater and where third control signal is operable to at least partially de-energize a second heater during in-rush current consequent upon energising said electric motor.

34. The computer readable media of claim 33 wherein said molding system comprises an injection molding machine, said electric motor is an hydraulic pump motor, said first heater is a barrel heater and said second heater is a mold heater.

35. The computer readable media of claim 34 wherein said at least partially de-energising said barrel heater comprises suspending power to said barrel heater and wherein said at least partially de-energising said mold heater comprises suspending power to said mold heater.

36. The computer readable media of claim 27 wherein said at least partially de-energising said first electrically powered system component comprises suspending power to said first electrically powered system component.

37. The computer readable media of claim 27 wherein said molding system is at least one of a molding machine and an auxiliary equipment of said molding machine.

38. The computer readable media of claim 37 wherein said auxiliary equipment includes at least one of:

a coolant chiller, a dehumidifier, a compressor, a robot, a compressor, and/or a resin dryer, and any combination or permutation thereof.

39. The computer readable media of claim 37 wherein said first electrically powered system component and said second electrically powered system component are configured in said molding machine.

40. The computer readable media of claim 37 wherein said first electrically powered system component and said second electrically powered system component are configured in said auxiliary equipment.

41. The computer readable media of claim 37 wherein said first electrically powered system component is configured in one of said molding machine and said auxiliary equipment and said second electrically powered system component is configured in the other of said molding machine and said auxiliary equipment.

42. The computer readable media of claim 37 wherein said machine controller cooperable with one of said an auxiliary controller, said first electrically powered system component, and/or said second electrically powered system component to send said third control signal.

43. An apparatus for managing electric service loads, the apparatus comprising:

means for energising a first electrically powered system component;

means for energising a second electrically powered system component;

means for de-energising, at least partially, said first electrically powered system component when (i) said electrical service load exceeds a threshold, or (ii) said electrical service load is expected to exceed said threshold.

44. The apparatus of claim 43, wherein said apparatus is embodied in a machine controller within a molding system.