CS254553B1 - Wiring to indicate slippage or skidding of railway traction vehicles - Google Patents

Abstract

The solution concerns a circuit for indicating slip or skidding of railway track vehicles, in which at least two monitored axles are equipped with pulse sources, operating on the principle of determining the difference in the number of revolutions of individual axles. The circuit includes an input circuit, a selection circuit, a subtraction circuit and an evaluation circuit. The selection circuit is connected with its output of the frequency of the selected axle to the control input of the phase-locked circuit, while its output of the frequency of the comparison axle is connected to the common input of the subtraction circuit.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a slip or shear indication circuit for railway traction vehicles in which at least two axles of interest are provided with pulse sources operating on the principle of determining the speed difference of individual axles.

The hitherto known slip or axle skid indication devices operate on the principle of determining the speed difference. They evaluate the axle with the lowest speed while driving and when braking the axle with the highest speed and slip or skid is indicated as exceeding a certain speed difference between the tracked and the selected axle.

This method of evaluation assumes that there is no simultaneous slipping or skidding of all axles, which, however, may not always be achieved on vehicles with all driven axles, and in this case the anti-skid device will fail, especially in the case of synchronous axle slipping under poor adhesion conditions.

The above disadvantage is overcome by the circuitry for indicating the slip or shear of railway traction vehicles according to the invention. The circuit includes an input circuit, a selection circuit, a subtraction circuit, and an evaluation circuit. It is an object of the invention that the selection circuit is connected to the control input of the phase locked circuit by its output of the selected axle frequency, whose output of the comparison axle frequency is connected to a common input of the subtraction circuit. The phase locked circuit is connected to the outputs of the evaluation circuit by its blocking inputs.

Higher effect is achieved by the circuit according to the invention irrespective of the number of axles to be compared, the phase lock action, which, when rapidly changing the frequency of the selected axle corresponding to slip or shear, limits this speed so that . In this way, if all axles, including the selected axle, slip or skid at the same time, the slippage or skid of all axles will be indicated as a result of the difference between the frequency of each axle and the frequency output of the phase locked phase comparator axle frequency. .

Another effect of the invention is achieved by connecting the inputs of the phase lock circuit blocking to the outputs of the evaluation circuit. As a result, after the slip indication, a further increase in the frequency at the output of the reference axle frequency is blocked completely or in the required size, and thus a much better agreement between them and the actual vehicle speed is achieved. The wiring increases the effect of the current anti-skid and anti-skid devices by providing reliable operation even in the cases where the previous devices have failed or operated with a long delay. Therefore, the immediately achievable tractive effort of the vehicle can be utilized to the maximum, without the risk of slipping or skidding and the consequent adverse consequences.

Fig. 1 shows an example of a slip or shear indication device for railway traction vehicles according to the invention.

The four drive axles of the vehicle are equipped with pulse sources 10. The circuit comprises an input circuit 3, a subtraction circuit 4, an evaluation circuit 5, and a phase lock circuit 6, wherein the selection circuit 2 is connected to the control input of the phase lock circuit 6 by its frequency output of the selected axle 7. the comparator axle 9 is connected to a common input 10 of the subtraction circuit 40. The phase locked circuit blocking inputs 12 are coupled to the outputs 11 of the evaluation circuit 5.

The wiring works in such a way that if at least one of the monitored axles rolls without slipping or skidding, the frequency at the control input i of the phase lock circuit 8 is exactly equal to the frequency · at the frequency output of the comparator axle 9. of the axle 7 was directly connected to the common input 10 of the subtraction circuit 4. If all axles, including the selected axle, slip or shear, the phase lock circuit 6 causes the frequency to increase only at a speed corresponding to the operational acceleration of the vehicle at the common input 10 of the subtraction circuit 4. In addition, if the outputs 11 of the evaluation circuit 11 are connected to the inputs of the blocking circuit 12 of the phase locked circuit 6, this increase is blocked completely or to the extent necessary, thereby extending the slip or shear indication practically until it is complete.

Claims (2)

Wiring for indicating slip or shear of railway traction vehicles in which at least two axles of interest are equipped with pulse sources operating on the principle of determining the difference in the number of revolutions of the individual axles comprising an input circuit, a selector circuit, a subtraction circuit and an evaluation circuit; the selection circuit (3) is connected with its selected axle frequency output (7) to the phase lock (6) control input (8), and its comparison axle frequency output (9) is coupled to a common input (10) of the subtraction circuit (4) . Wiring according to claim 1, characterized in that the phase locked circuit (6) is connected by its blocking inputs (12) to the outputs (11) of the evaluation circuit (5).