Patent GB-298532-A (GB)
Title: Improvements relating to railway or like crossing gates or barriers
IPC: B61L29/22
Filed: 1928-10-01
Abstract: 298,532. Standard Automatic Signal Corporation, (Assignees of Vincent, O. L.). Oct. 10, 1927, [Convention date]. Operating barriers electrically and by treadles and the like checks. - Mechanism for operating a railway crossing barrier comprises a normally open or closed circuit ada.pted to operate a single track relay by the passage of a train or car over a track section, said relay having its actuating coil connected in the track circuit for directly operating a two-way selector switch adapted for closing a. second independent motor operating circuit through either a barrier opening branch or a barrier closing branch thereof. The barriers are also subjected to the action of pneumatic check devices and are mounted so as to yield when struck by or on contact with passing road vehicles. As shown, a counterweighted bar 22, serving as a barrier for a road vehicle, and a barrier 23 for the sidewalk, both of which may carry warning lights 28, are rotatably mounted on shafts 60, 61 respectively. These shafts are carried by a standard 20, Figs. 1 and 4, in the lower part of which is an electric motor 32. The motor drives through suitable gearing a shaft 38 on which is disposed at one end a crank 42 connected by a link 43 to a cross-head 45. This cross-head is attached to a rack 63 that is in gear with a pinion 62 on the shaft 61, and this shaft is connected to the shaft 60 through a loose pinion, coil spring, rack 67 and pinion 68. An extension 69 of the rack 67 ends in a piston that is movable in a pneumatic check or brake cylinder 25. The cylinder 47 in which the cross-head 45 is reciprocated is rotatably mounted on roller bearings 48, and is kept in its normal position by springs 52, 53 that are adapted to yield when the barrier is struck by an object or obstruction. The shaft 61 is provided with an arm adapted to make contact with a switch element for controlling the operation of the lights 28, and switch elements 83, 87, 91, 94 are provided on the shaft 38. Of these elements, the members 83, 87 have a constant electrical connection with one terminal of the motor 32, the element 91 controls the lighting of the lamps 28, and the member 94 controls the operation of the bell 26. Fig. 12 represents the arrangement and wiring of parts for the operation of barriers on either side of a railway crossing 151 of a railway track 150. An oncoming train closes the normally-open track relay and a circuit is completed to energise the relay 154, current passing through conductors 152, 191 to the signal 153, through conductors 191, 156 to battery 157, and through conductors 15S, 159 to complete the track relay circuit. The relay 154 is energized through conductor 152 and back through con ductors 155, 156. The relay 154 being energized, arms 177, 178 are moved into engagement with contacts 186, 187 so that current passes from conductor 161 through conductors 184, 182, arm 177, contact 186, conductor 188 to switch elements 85, 83, and to motor 32 through conductors 167, 169, a conductor 170 completing the circuit to the negative side of the actuating circuit. The motor 32 is geared to the shaft 38 so that the shaft is revolved through 180‹ only to lower the barrier, this movement causing the connection to be broken between the finger 85 and lug 84 but closing contact between the element 87 and finger 89 so that the motor circuit is completed through the wire 163. Contact is also made between the finger 93 and the element 91, causing current to flow through from conductor 163 to conductor 171 and lamps 28. The projections 95 of the serrated switch element 94 make intermittent connection with a finger 96, the warning lamps 26 being thereby actuated intermittently. The current also passes from the wire 164 through contact 187 to the switch elements of the barrier unit on the other side of the trackway, in a manner similarly to that previously described. After the train has passed out of this section of the trackway controlling the crossing gates the relay 154 is de-energized and the arms 177, 178 are moved into contact again with members 179, 180. By this' time the lug 84 has revolved into contact with the finger 86 so that current is passed from the arm 177 to contact 179 through conductor 181, finger 86 and lug 84 to complete the motor circuit through conductor 169, causing the barriers to be restored to the open position. Modified arrangements are described in which the switch elements 91, 93 controlling the lighting circuit are omitted, and a motor circuit is described using a four-wire reversible motor.