| 摘要 |
A plurality of stationary markers (A, B, C, and D) are symmetrically placed at predetermined locations in the right of way of an electrically propelled traction vehicle on opposite sides of a transition point coinciding with a gap (14) between adjacent sections (13a, 13b) of a wayside conductor. Proximity sensing means (PSR, PSL) on the vehicle provide discrete output signals on a first line (43) upon passing the first and third markers (A and C) and on a second line (44) upon passing the second and fourth markers (B and D). Receiver logic means (42) includes means (108, 111-115, and 118-127), responsive to the output signals on the first and second lines, respectively, for producing a first control signal (on line 51) during the first-to-third marker interval and a second control signal (on line 50) during the second-to-third marker interval. Means (24, 25, 55, and 60-71) is provided for disconnecting the vehicle's propulsion system (27, 29, M) from a current collector (16) either in delayed response to the start of the first control signal or in immediate response to the start of the second control signal, whereby the vehicle will coast unpowered as its current collector slides across the gap in the wayside conductor. Additional means (56, 75, 82-85) is provided for reconnecting the propulsion system in response to the termination of both of the control signals. Malfunction indicating means (52, 130-145) is provided for detecting any discontinuity in the normal sequence of output signals that are provided on the first and second lines as the proximity sensing means passes all of the markers in the vicinity of the transition point. |
