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. 30, 1978
Filed:
Feb. 16, 1977
John David Markham, Manchester, EN;
Associated Electrical Industries Limited, London, EN;
Abstract
A braking system for, primarily, separately excited D.C. traction motors, in which rheostatic braking is effected by field reversal to generate armature current freewheeling through the low impedance supply and through a brake resistor in series with the armature. A contactor shorts out the brake resistor for normal motoring. Field excitation in conjunction with armature current or armature voltage polarity reversal is detected to indicate the motor generating function, lock open the motoring contactor and prevent short circuiting of the motor/generator. Plug braking by energisation of the armature supply is thus always permissible either by brake handle and power handle or reverse handle and power handle. The armature current then contains a rheostatic braking component and a tractor braking component. What would normally be mis-use of the reversing control to achieve rapid deceleration thus becomes acceptable.