Patent GB-913195-A (GB)
Title: Automatic control system for railway classification yards
IPC: B61L17/00
Filed: 1961-07-26
Abstract: 913,195. Classification yard control systems. WESTINGHOUSE AIR BRAKE CO. July 26, 1961 [Aug. 12, 1960], No. 27115/61. Class 105. In an automatic control system for a classification yard which includes a hump, a master retarder and a number of group retarders, means are provided for determining the velocity at which a cut of one or more vehicles should leave its intended group retarder before the cut enters the master retarder and means are provided for so controlling the master retarder that the cut arrives at its intended group retarder a predetermined time after leaving the hump. On entering track section A1T, a cut selects one of a number of storage panels for storing all information pertaining to the cut, the selection establishing a binary code for panel identification which is subsequently used for insertion or read-out of information. Information is inserted during the period the cut occupies tangent track section A1T and curved track sections A2T-CT and comprises route details WC; weight classification W, as determined by weight detector WD; number of vehicles per cut (one or more) YN, as determined by a light-responsive device acting in conjunction with track circuits associated with sections A1T and A2T; vehicle speed V2 in tangent track section A1T, as measured by radar velocity meter RVM1; tangent track rolling resistance Rt, as determined from the speed measurement by differentiator D1F, wheel inertia correction coil W1CU, bias coil BC1 and the weight classification apparatus; and vehicle speed V3 in curved track section CT, as measured by radar velocity meter RVM2. Squaring apparatus in the storage panel makes available at the output of the panel voltages proportional to V 2 <SP>2</SP> and V 3 <SP>2</SP>. On entry of the cut into section CT the stored information is applied to computing means for determining the curved track rolling resistance of the cut and its leaving speed from its intended group retarder. The leaving speed is computed from the values of tangent and curved track rolling resistance, the length, curvature and grade of the track beyond the group retarder and the fullness of the storage track. A voltage V6 proportional to the leaving speed is inserted in the storage panel until required. The speed measurement V3 is also applied via bias unit BU4 to a computer or summing amplifier X10SA to which certain voltages representing yard constants are supplied. The amplifier provides a signal which is stored in unit MR1ESU until the cut enters the first section of the master retarder. On entry the signal is applied with cut weight information and speed information from radar velocity meter RVM3 to the retarder first section control unit MR1SCU which controls the first retarder pressure and is also supplied to storage unit MR2ESU from which it is supplied with weight and speed information from radar velocity meter RVM4 to the control unit of the second section of the retarder as the cut enters. The master retarder control is effective to control the leaving speed of the cut so that it arrives at its intended group retarder a predetermined time after leaving the hump. During passage of the cut through the yard, the stored route information is made available as required from the storage panel and on entry to the group retarder the leaving speed V6 is applied to the retarder control unit 1-2SCU which releases the retarder when the speed of the cut, as measured by radar velocity meter RVM5, has been reduced to the required value. Entry of the cut into its allocated storage track generates a cancel signal for the release of the storage panel. When the cut entered the master retarder MR1T, the track fullness storage for the designated storage track was adjusted to include the cut. Specifications 772,135, 792,135. 898,792, 903,741, 903,744 and U.S.A. Specifications 2,352,299, 2,863,991, 2,863,992, 2,908,865 are referrred to.