SU1495658A1 - Device for simulation of i.c. engine operation - Google Patents

Abstract

The invention can be used to simulate the amplitude-time processes of engines. The purpose of the invention is to expand the functionality of the device. The output of the control unit 1 through the converter (P) 2 code-frequency is communicated with the input of the counter (C) 3, the first output of which is connected to the inputs of permanent memory devices (ROM) 8 and 9, and the overflow output - with the second input. The output of ROM 9 is connected to the digital-analogue P 12, the first output of ROM 8 is connected to the third input C 4 and the first input C 5, and the second output of ROM 8 to the input of the driver 13 pulses. The second input C 4 is connected to the output of the pulse generator 6, its first input to the output of the block 10 coincides, and its output to the input of the block 10 and the first input of the ROM 7, to the second input of which the output C is connected. The output of the ROM 7 is connected the digital-to-analog input is P 13, and the outputs of P 11, driver 13 and P 12 are respectively. the outputs 14, 15 and 16 of the device. The device allows you to simulate the working processes of the engine by synchronizing the operation of the entire device with the operation of C 3 and ROM 8. 2 Il.

Description

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The invention relates to the instrumentation of internal combustion engines (ICE), in particular to devices for testing engine diagnostic equipment, and can be used to simulate the amplitude-time processes of two.

The aim of the invention is to expand the functionality of the device.

Figure 1 shows the functional diagram of the device; figure 2 - diagrams of his work.

Figure 2 shows the signal at the first output of the ROM (a), the diagrams of the third counter (b), the signal at the second output of the ROM (c), the output signal of the DAC (d) and the output signal

DAC (d).

The device contains a control unit 1, a code-frequency converter, a fourth 3, a second 4 and a third 5 counters, a pulse generator 6, the first 7, the third 8 and the second 9 permanent memory devices (ROM), a coincidence unit 10, the first 11 and the second 12 digital-analogue transform, spruce (DAC), il3 pulse former.

The output of the control unit 1 is connected to the input of the converter 2 code - frequency, the output of which is connected to the input

are made by the output of control unit 1. The counter 3 is in the continuous counting mode and carries out periodically repeating sequential search of the ROM 8 cells. At the same time, a signal is generated at the first output of the ROM 8 (Fig. 2a), which controls the operation of the counter 4, and at the second output of the ROM 8 (Fig. 2c ) - single; pulse, which, using the shaper 13 on the output bus 15 of the device, generates a signal that simulates the mark in mt. the first cylinder (figg).

In addition, counter 3 carries out a periodically repeating sequential search of the cells of the ROM 9, the contents of which are entered as a code at the input of the DAC 12. At the output 16 of the device, an analog signal periodically repeating from cycle to cycle is generated. battery voltage when the engine is started or any other signal i whose temporal characteristics are inversely proportional to the frequency of the pulses input to ROM 9, i.e. have constant phase characteristics regardless of the magnitude of the simulated rotation frequency.

The state of counter 4 is determined by the control signal from the first output

the house of the counter 3, the first output of which is 35 and the ROM 8 (FIG. 2a). For example,

connected to the inputs of the ROM B- and 9, and the output of the latter is connected to the input of the DAC 12. The first output of the ROM 8 is connected to the third input of the counter 4 and the first input

counter 5, the second input of which is under-40 to the entrance of the resolution of the count of the counter 4

The key is connected to the overflow output of the counter 3, and the output is connected to the second input of the ROM 7, the output of which is connected to the input of the DAC 11, and the first input is connected to the output of the counter 4 and connected45 low (Fig.2a) counter 4 times with the input of the block 10 coincidence output which is connected to the first input of the counter 4, the second input of which is connected to the output of the generator, 6 pulses.

The outputs of the DAC 11, the driver 13 and the DAC 12 are the outputs 14-16 of the device, respectively.

The device works as follows.

The inputs of counter 3 receive pulses from the output of converter 2, the frequency of which, and hence the overflow time of counter 3, is detected at the first output of ROM 8 of a high level signal at the outputs of counter 4 there are low potentials and from the output. block 10. match

Potential for the latter to work.

In the transition potential at the first output of ROM 8 from a high level to

0

The pulses from generator 6 are blocked and start counting. In this case, the corresponding cells of ROM 7 are sequentially searched and the values recorded in them are fed to the input of CAI 11, the output of which (device output bus 14) generates an analog signal whose samples are written in 5 Danny Bank ROM 7 (tt,), figg). The described process lasts until the state of the counter 4 becomes such that it triggers the block 10 coincidence, thus blocking the operation

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non state. This state corresponds to the last sample recorded in ROM 7 in this bank. In this state, the device is up to the point in time when the potential transition occurs at the first output of the ROM 8 from a low level to a high one (, Fig. 2a). In this case, the counter 4 is reset, and the potential corresponding to the numerical value of the code recorded at the zero address of the ROM of this bank is set on the output bus 14 of the device. In addition, at this point in time, the state of the counter 5 changes (, FIG. 26), which causes each subsequent actuation of the counter 4 to cause the information recorded in the next ROM 17 to simulate signals with different parameters depending on the order within the cycle (fig.2d) At the end of each simulation cycle, counter 5 is reset, for example, by an overflow signal from counter 3, which is necessary to synchronize the switching of ROM blocks 7 with the start of the simulation cycle formation ( , Fig.26). The period of the simulation cycle is given by the following expression (Figure 2d):

TC Mcr / f, where MCT is the counting module of the counter 3;

f is the frequency of the pulses at the output of the converter 2. The operation of the counter 3 is considered when the duration of the counter enable signal (coming from the first output of ROM 8)

/ SG. 7d to McT / fo, where MCT is a counter 4 counting module;

f is the frequency of the pulses at the output of the generator 6.

In the case when dt 3t ,, counter 4 is reset before the coincidence unit 10 is triggered (Fig. 2a). In this case, a potential is established on the output bus 14 of the device, which corresponds to the numerical value of the code recorded at the zero address of the ROM of this bank (t t, fig.2d).

The phase shift of the signals at the outputs 14 and 15 of the device in steady state is a constant value (Fig. 2):

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Thus, the device makes it possible to simulate not only a change in the rotation frequency, but also two working processes, the operation of the ignition system of the carburetor engine, the injection system of the diesel engine, etc. This is achieved due to the fact that the operation of the entire device is synchronized with the counter 3 and a ROM 8. At the output 14 of the device, signals are formed in this case, the temporal characteristics of which do not depend on the duration of the simulation cycle, and their parameters are different depending on the order of succession (non-uniformity is simulated engine work from cylinder to cylinder). At the output 16 of the device, a signal is generated whose temporal characteristics are determined by the simulated rotational frequency, i.e. has constant phase characteristics within the simulation cycle. The output of the device 15 is formed, imitating the marks of V.M.T., for example, of the first cylinder and having constant phase characteristics with respect to the signal at the output 14.

Claims (1)

Invention Formula A device for simulating the operation of an internal combustion engine, comprising a reference signal generator, a pulse shaper and a control unit, characterized in that, in order to expand its functionality, the device is additionally equipped with a first counter with two outputs, a second counter with two inputs and a third counter with three inputs, the first with two inputs, the second with two outputs and the third permanent storage devices, the first and second digital-to-analog converters, converters, the code is often This is also the case of a coincidence unit, the control unit through a code to frequency converter is connected to the input of the first counter, the first output of which is connected to the inputs of the third and second permanent storage devices, and the output of the last one is connected to the input of the second digital to analog converter memory device is connected to the third input of the third counter and the first input of the second counter, the second input of which is connected with the second output of the first counter, and the second output of the third constant first - second input of the first constant, J -. .. The device is connected to the input of the imager, the output of the second counter is connected to the first input of the first permanent storage device. the remembering device, and through the coincidence unit - with the first input of the third counter, the second input of which is connected to the generator output. FI.2 the output of which is connected to the input of the first digital-to-analog converter, the output of the third counter is connected with   -. .. the remembering device, and through the coincidence unit - with the first input of the third counter, the second input of which is connected to the generator output.