Circuit for automatic operation of a series brake upon power loss during a regenerative braking period
AssigneeSquare D Company
InventorPatrick J. Bowers
Life of this patent
Estimating the term…
Abstract
An anti-regeneration circuit for preventing a regenerated current produced by an overhauling DC motor from setting a series brake. The anti-regeneration circuit includes a current blocking device 90 which blocks the flow of regenerated current in the crane control circuit 10 and a surge suppresser 94 for protecting the current blocking device 90 from a high inverse peak voltage produced by de-excitation of a crane control circuit 10 upon the sudden loss of power.
Claims20
An operating circuit for a crane having a DC lifting motor circuit and a control circuit, said operating circuit comprising:
- a series-wound brake activating solenoid;
- an anti-regeneration circuit including a current blocking device electrically in series with said series-wound brake activating solenoid and a surge suppresser electrically in parallel with said control circuit, said current blocking device preventing a regenerated DC current from flowing in said control circuit and said surge suppresser protecting said blocking device from a reverse DC voltage spike caused by a sudden loss of power in said control circuit.
A crane operating circuit comprising:
- a DC power source for providing power to a DC lifting motor circuit and a control circuit;
- a series brake activating circuit for activating a series brake upon a sudden loss of said power provided by said DC power source;
- a current blocking device for blocking a regenerated current produced by the overhauling of said DC lifting motor resulting from said sudden loss of power, said blocking device preventing the regenerated DC current from flowing in said crane control circuit and thereby maintaining said series brake activating circuit in an non-activating state;
- a surge suppresser for protecting said current blocking device from a high peak reverse voltage caused by the sudden loss of power in the control circuit.
An anti-regeneration circuit for retrofitting a DC crane operating circuit having a motor circuit and a control circuit, said anti-regeneration circuit comprising:
- a printed circuit board having a plurality of electrical terminations, each said termination providing a connecting means to particular point of the DC crane operating circuit;
- a current blocking device mounted on said printed circuit board, said current blocking device having a first end electrically connected to a first one of said plurality of electrical terminations and a second end connected to a second one of said plurality of electrical terminations;
- and
- a surge suppresser also being mounted on said printed circuit board, said surge suppresser having a first end electrically connected to a third one of said plurality of electrical terminations and a second end electrically connected to a fourth one of said plurality of electrical terminations.
Dependencies are inferred from the claim text.