Justification of Requirements to Equipment Providing for Occupancy-Dependent Automatic Braking Effort Regulation on EMUs
Increase in capacity of commuter EMUs generates the need for automatic braking effort regulation subject to train occupancy. There has been proposed method for determining automatic mode characteristics of brake cylinder pressure regulation. First of all there have been determined minimum and maximum permissible values (by conditions of efficiency and skidding correspondingly) of brake pressure exerted on wheels by iron and composition brake shoes. Basing upon the obtained values and brake system characteristics there has been defined brake cylinder pressure tolerance range covering all the possible occupancy situations. Relying on the obtained pressure values there has been proposed method for determining brake cylinder pressure change characteristic as a function of occupancy. Its idea lies in determining parameters of linear functions, kept within the bounds of tolerance range characterizing the automatic mode operation. These parameters are treated as required automatic mode characteristics. In a similar fashion there has been justified characteristics calculation method of automatic mode, employing spring cambering for determining commuter car occupancy. As a case in point there has been conducted the above mentioned calculation for electric train ED4M cars.