The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 13, 1980
Filed:
Sep. 09, 1977
The Furukawa Electric Co., Ltd., Tokyo, JP;
Abstract
A control system for automatic operation of travelling objects through a power supply system without using any signal communication systems. Either a DC power source or three-phase AC power source is utilized as a power source. With the system employing a DC power source, three trolley wires are installed, one a negative and two positive. Each of the positive wires is divided and insulated into sections of a predetermined length; the positive feeding trolley wires in each section is always supplied with the DC power, and the power to the other positive feeding trolley wire is switched on and off depending on the movement of travelling objects. Each travelling object is supplied with power by the three trolley wires has a DC motor, and when one of the positive wires has no voltage, this is detected and the braking is effected. The travelling object entering a station is automatically decelerated and stopped. When employing a three-phase AC power source, four trolley wires are installed, of which one is a neutral trolley wire and the remaining three trolley wires are with phases of AC power. Each of these three AC feeding trolley wires is divided and insulated into sections of a predetermined length, one of the three trolley wires is always supplied with the phase power, and power to the other two is switched on and off responsive to movement of the travelling objects, which travelling objects are equipped with an induction motor having star connected field coils and as power to the two AC feeding trolley wires is switched off, the unbalance current in the field coil flows to the neutral trolley wire causing braking.