Motor control system

Claim 1

A control system for periodically reversing the direction of rotation of an electric motor and restoring the original direction of rotation thereof after predetermined time delay in response to mechanical overload of means driven thereby comprising: electromagnetic relay means, two microswitch means, and two thermally responsive current-sensing switching devices, all in circuit with said motor and a source of electrical energy; said relay means comprising plural contacts connected in said circuit to cause said motor to rotate in either of two directions corresponding, respectively, to the energized and de-energized condition of said relay means; each said microswitch means being operable to isolate said motor from said source of energy in response to predetermined movement of the driven mEans, each said thermally responsive device comprising a current-sensitive heater means and a movable contact operably responsive thereto, said heater means thereof being in series circuit with an associated one of said microswitch means; whereby each said switching device is operated by its respective heater means in response to overload-induced excessive current in said circuit thereby to temporarily actuate said relay means from one to the other of its said energized and deenergized conditions and reverse said motor, until said associated one microswitch means operates to isolate said motor or said switching devive returns to its original circuit position, after a predetermined time delay in response to cooling of its heater means, whichever occurs first, restoration of said switching device to its original circuit position causing actuation of said relay means to the other of its said conditions to automatically restore the motor''s original direction of rotation.

Claim 4

A system for controlling a reversible electric motor drivingly coupled with a flag-carrying halyard in an automatic flagpole assembly, the systemy being operable to automatically reverse the direction of rotation of the motor in response to an obstruction to the free operational movement of the halyard and to restore the original direction of rotation of the motor after predetermined time delay comprising: electromagnetic relay means, two microswitch means, and two thermally responsive current-sensing switching devices, all in circuit with said motor and a source of electrical energy; said relay means comprising plural contacts connected in said circuit to cause said motor to rotate in either of two directions corresponding, respectively, to the energized and deenergized condition of said relay means; each said microswitch means being operable to isolate said motor from said source of energy in response to predetermined movement of the driven means, each said thermally responsive device comprising a current-sensitive heater means and a movable contact operably responsive thereto, said heater means thereof being in series circuit with an associated one of said microswitch means; whereby each said switching device is operated by its respective heater means in response to overload-induced excessive current in said circuit thereby to temporarily actuate said relay means from one to the other of its said energized and deenergized conditions, and reverse said motor, until said associated one microswitch means operates to isolate said motor or said switching device returns to its original circuit position, after a predetermined time delay in response to cooling of its heater means, whichever occurs first, restoration of said switching device to its original circuit position causing actuation of said relay means to the other of its said conditions to automatically restore the motor''s original direction of rotation.

Claim 5

A system for controlling a reversible electric motor drivingly coupled with a flag-carrying halyard in an automatic flagpole assembly, the systemy being operable to automatically reverse the direction of rotation of the motor in response to an obstruction to the free operational movement of the halyard and to restore the original direction of rotation of the motor after predetermined time delay comprising: electromagnetic relay means, two microswitch means, and two thermally responsive current-sensing switching devices, all in circuit with said motor and a source of electrical energy; said relay means comprising plural contacts connected in said circuit to cause said motor to rotate in either of two directions corresponding, respectively, to the energized and deenergized condition of said relay means; each said microswitch means being operable to isolate said motor from said source of energy in response to predetermined movement of the driven means, each said thermally responsive device comprising a current-sensitive heater means and a movable contact operably responsive thereto, said heater means thereof being in series circuit with an associated one of said microswitch means; whereby each said switching device is operated by its respective heater means in response to overload-induced excessive current in said circuit thereby to temporarily actuate said relay means from one to the other of its said energized and deenergized conditions, and reverse said motor, until said associated one microswitch means operates to isolate said motor or said switching device returns to its original circuit position, after a predetermined time delay in response to cooling of its heater means, whichever occurs first, restoration of said switching device to its original circuit position causing actuation of said relay means to the other of its said conditions to automatically restore the motor''s original direction of rotation.