Patent GB-1137109-A (GB)
Title: Apparatus for weighing railroad cars in motion
IPC: G01G19/04
Filed: 1966-10-10
Abstract: 1,137,109. Weighing railway cars. S. H. LEVINSON. 10 Oct., 1966 [22 Oct., 1965], No. 45214/66. Heading G4H. In apparatus for weighing railway cars in motion by summing the weights of trucks of a car, means are included to ensure that the weighing means is reset prior to the weighing of the first truck of a car whether or not all the trucks of the preceding car were weighed. Initiating a weighing cycle.-Switches SW1 to SW3 (Fig. 1) are so positioned that for both two and three axle trucks relays R3, R4 are energized together only when the truck is wholly on the weigh rails WR to initiate a weighing cycle by the energization of relay R7 which results in a conductor 25 being disconnected from ground. The weighing cycle begins when the rear wheel moves off switch SW3 to de-energize relay R4 and reconnect conductor 25 to ground to apply a read pulse to read logic 39 (Fig. 2). Delaying weighing to prevent errors due to vibrations.-On receipt of a pulse on conductor 25 (Fig. 2) read logic 39 generates pulses on conductors 40, 41, 42 to reset a clock 43, to reset the five decades of counter 52 and prepare a gate 45 respectively. The clock then counts up to its maximum before it enables the gate 45 by a pulse on conductor 53, a count continuing until the clock reaches a preset value when it closes gate 45 by a pulse on conductor 60. Weighing apparatus.-The weighing apparatus preferably comprises load responsive transducers, e.g. Wheatstone bridges which produce a voltage proportional to the weight on the weigh rails. The voltage signal is converted into a train of pulses of frequency proportional to the weight, the pulses being transmitted on conductor 54 via gate 45 which is enabled for a fixed time and accumulated in the counter 52. Overspeed indicating.-If the train moves much too quickly or slightly too quickly over the weigh rails, the energization of relay 10 or 9 respectively whilst gate 45 is still enabled results, in the first ease, in AND gates 83 and 82 (Fig. 1A) being enabled to control a " print error " command on conductor 78, a continuous horn and flashing light and, in the second case, in AND gate 79 being enabled to intermittently sound the horn and continuously light a lamp. Single or dual-mode operation.-The counter 52 is read out by a pulse on conductor 46 after each weighing with switch 206 in its single mode position when a print command signal on conductor 59B is generated on the closure of gate 45. When the switch is in its dual mode the print command signal is fed to a bi-stable device in reset logic 44 and the counter is not read out until the bi-stable is reset on the next print command signal. Automatic recycling.-With the apparatus in its dual mode position, when the front wheel of the rear truck of a car actuates switch SW3, relay R4 is energized to energize relay R8 which locks on. If synchronism exists, the rear wheel of the truck actuates switch SW3 to re-energize relay R4 and relay R7 and de-energize relay R8. If, however, switch SW3 is not operated due to a fault, when switch SW4 is closed by the front wheel of the rear truck to energize relay R9 a reset pulse is transmitted on conductor 109 to zeroize the counter resulting in a zero weight being printed. Similarly if the rear wheel of the first truck fails to actuate switch SW3, the rear truck is moved on to the weigh rails without the first truck having been weighed and relay R8 is energized. As the rear truck moves off the relay R9 is energized to apply a pulse on reset conductor 109 as before. Preventing weighing of the locomotive.-The switches SW1-SW3 are so positioned that the front wheel of the locomotive actuates the three switches to energize relays R2, R3, R4 and consequently relay R5 to disconnect print command conductor 59B before the rear wheels reach the first switch SW1. Manual reset.-If it is required to accumulate all the weights in counter 52, switch 115 (Fig. 2) is moved to its manual position which prevents the pulse on conductor 41 resetting the counter 52.