Digital on-board clutch tester

Abstract

The work is devoted to the creation of a digital type on-board device for diagnosing the clutch of traction vehicles (TTM) and allows to determine with high accuracy the slipping of the clutch when faults appear in it. The principle of operation of the device is based on the use of digital technology for measuring the rotational speed (number of pulses) in the digital code of the flywheel and the input shaft of the gearbox (GB). With the help of light-emitting diodes, the received digital codes are displayed, displaying the number of voltage pulses per second from the flywheel speed sensors and the gearbox primary shaft gear. The received digital codes are converted by the driver (operator) into the decimal number system. Given that the number of flywheel teeth is greater than the number of gear teeth, the number of pulses from the sensors is adjusted by dividing the number of pulses from the flywheel per revolution by the ratio of the number of flywheel teeth to the number of gear teeth. Next, the difference between the corrected number of pulses from the gear and the flywheel is determined, which is compared with the permissible number of pulses and, based on the comparison, a conclusion is made about the technical condition of the clutch. If the difference is equal to zero or less, the clutch will be considered good. The device for diagnosing the clutch includes two digital speed sensors, each of which contains an inductance coil with a magnetic core, rigidly fixed near the flywheel teeth and gears of the input shaft of the gearbox. The first differentiating circuit, with a cut-off diode at the output, the input is connected to the inductor and is made on the first and second resistors and capacitor. The second differentiating circuit with a cut-off diode at the output is made on a resistor and a capacitor, and the input is connected to the output of the self-oscillating multivibrator. The self-oscillating multivibrator is made on two logical elements NAND, two capacitors, two diodes and two resistors. The output of the second differentiating circuit is connected to the zero-setting inputs of sixteen-bit summing electronic counters. The outputs of the logical elements AND are connected by means of resistors with the counting inputs of two electronic counters, at the output of which digital codes are formed, which reflect the rotational speed of the flywheel and gears of the input shaft of the gearbox. An example of calculating the parameters of the elements of the differentiating circuit of an auto-oscillating multivibrator is given.