Patent GB-1183071-A (GB)
Title: Coupling System
IPC: B61L17/00
Filed: 1967-02-02
Abstract: 1,183,071. Vehicle speed control. AMERICAN BOSCH ARMA CORP. 2 Feb., 1967 [2 Feb., 1966], No. 5202/67. Heading B7N. [Also in Divisions F2 and G3] In an arrangement for reducing the speed of a free rolling rail vehicle to a value which allows it to couple safely with a vehicle in advance, e.g. in a classification bump yard, first and second object detecting and ranging apparatus are provided on the vehicle, the first controlling the braking when the vehicle in advance is stationary and the second controlling the relative speed to a safe value when the vehicle in advance is detected as moving. The maximum speed of the free rolling vehicles in the yard is also controlled in dependence on their weight. On uncoupling the vehicle for bumping, pressure drops in the brake pipe 16 but the brakes are prevented from operating by a release valve associated with the brake control valve 23 which is manually set or tripped. The drop in pressure also actuates switch 87 to the position shown in which on movement of the vehicle a D.C. supply provided by wheel operated alternator-rectifier 45 is connected to line L-8. The alternator also supplies a signal having a frequency proportional to vehicle speed to line L-4 and when this speed exceeds a low value defined by low pass filter 110 low speed detector 112 operates a relay 1CR. The D.C. supply is now applied via contact 1-1CR of the relay and contact 1-1LS or 2-1LS of a direction switch 1LS to energize the first and second object detecting and ranging apparatus at the leading end of the vehicle-in the case shown-the ultra-sonic system including oscillator 114 and pulser 115 and the radar device 116. The pulser 115 controls a gate 130 via which the ultra-sonic oscillator output is applied on line L1 to transmit-receiver 47 and also controls a gate 132 via which signals reflected from objects. e.g. vehicles in advance, in the range 20-75 ft. ahead of the vehicle are applied via integrator 133 to operate relay 4CR which via contact 1-4CR operates the brakes on the vehicle to bring its speed to the coupling speed defined by the pass frequency of low pass filter 110. When low speed detector 112 receives no signal relay lCR releases, de-energizing the apparatus thereby removing the braking action and allowing the vehicle to couple with that in advance at a safe speed. During movement of the vehicle through the yard its speed is controlled by applying the D.C. supply via a contact 1-2LS or 2-2LS in dependence on whether the vehicle is loaded or not to a detector 120 or 121 associated with pass filters 122, 123 respectively. The detectors determine whether the vehicle speed exceed say 8 m.p.h. when it is loaded or 11 m.p.h. when it is unloaded and by operating relays 2CR and 3CR keep the speed below these limits. The radar device 116 and transmit and receiver 150, 152 provide by Doppler effect a D.C. voltage which is a function of the relative speed of the vehicle and a vehicle in advance. This is subtracted in comparator 160 from a D.C. voltage from high speed detector on line L-51 representing the vehicle speed to provide an indication if the vehicle in advance is moving and this signal operates a relay 8CR to cut out the brake applying relays of the ultra-sonic ranging system out of circuit. In addition to the subtraction result is added a voltage representing coupling speed and the resultant representing the speed of the vehicle in advance plus the safe coupling speed is compared in comparator 161 with the vehicle speed and if this is excessive for safe coupling the brakes are applied by operation of relay 6CR to reduce the speed to the required value.