SU1560748A1 - Method of cyclic running-in of ic-engine - Google Patents

Abstract

The method of cyclic run-in of an internal combustion engine (ICE) saves fuel and lubricants during a hot run-in of ICE without external load. This is achieved in that the run-in is carried out in alternating cycles, each of which consists of the period of the ICE working process and the period of forced rotation of the crankshaft from the electric drive of the stand when the power supply system, ignition system, and coolant circulation are turned off. Figure 1 shows a variant of the structural scheme of the device for implementing the method. After cold scrolling from the electric drive of the stand, the ignition system 5, power supply system 6, cooling system 7, 8 are connected to the internal combustion engine and the engine is started. When stabilization of the engine temperature is achieved, the thermometric alarm 9 starts the control unit 4, automatically switching off the operation of the ignition system, power supply system, water circulation, and activating the electric drive of the stand, which forcibly rotates the engine crankshaft. When a certain level of temperature decrease is reached relative to the previous value, the systems are switched on to the ICE working process and at the same time the electric drive of the stand is turned off. Figure 2 shows a sequence diagram graphically illustrating the process of engine running in cycles, each of which consists of two periods: the first period of hot running without load and the subsequent second period of forced rotation of the crankshaft in the temperature mode of the working process. 2 Il.

Description

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In order to stabilize the engine's temperature, the thermometric alarm 9 starts the control unit 4, which automatically turns off the functioning of the ignition system, power supply system, water circulation and activates the electric drive of the stand, which forcibly rotates the crankshaft of the internal combustion engine. When a certain level of temperature decrease is reached relative to the previous value,

switching on the systems to the workflow of the internal combustion engine and at the same time switching off the electric drive of the stand. Figure 2

a cyclogram is presented, graphically illustrating the process of engine running in cycles, each of which consists of two periods: the first period of the hot running without load and

followed by a second period of forced rotation of the crankshaft in the temperature mode of the working process. 2 Il.

The invention relates to the testing of internal combustion engines (ICE), and in particular to methods of running of an internal combustion engine on grinding wheels and t stands.

The purpose of the invention is to reduce fuels and lubricants during hot running.

Figure 1 is a diagram of an obkatomno-brake stand, designed to implement the method, and figure 2 is a cyclogram graphically illustrating the process of running the internal combustion engine.

The method is implemented as follows.

After cold cranking of the engine crankshaft 1, mounted on the uprights 2, from the electric drive of the wheeling stand 3, the ignition system 5, power 6, cooling 7 and 8 are turned on by means of control unit 4 and the engine is started up for hot running without load. Upon reaching stabilization of the thermodynamic mode of the engine, the thermometric alarm 9, controlling the thermodynamic mode of the engine on the oil temperature in the crankcase 10, gives a signal to the control unit 4, which automatically turns off the ignition systems 5, power 6, coolant circulation 7 and 8 and turns on electric drive of the stand 3. The latter forcibly rotates the crankshaft of the engine 1.

When a certain level of decrease in the temperature of the oil in the crankcase 10 of the engine 1 is reached, the thermometric alarm 9 gives a signal to the control unit 4, which disables the electric drive of the bench 3 and simultaneously switches on the ignition system 5, power 6, coolant circulation for operating ICE process without load.

Thus, the regular time of the hot running of the ICE without load is divided into a number of cycles, each of which. consists of the engine's working period and the period

forced rotation of the crankshaft from the electric drive of the bench at a temperature determined by the stabilization zone of the thermodynamic mode of the internal combustion engine.

The stabilization zone of the thermodynamic regime is determined by the typical characteristics of the heating process (Fig. 2), which, without taking into account the ambient temperature, may be

represented by exponential dependency type

r -frjd - e)

(one)

0

5 where j is the temperature rise

crankcase oil above the environment; oh - steady value

temperature conditions; t is the time of the heating process; .T is the heating time constant;

e 2.72 - the base of natural logarithms.

Analysis of equation (1) shows that at t 0, Ј 0, at 0 t t. T there is an intense increase in temperature. In this case, the process of stabilization of the thermodynamic regime takes place. The transition point from the temperature rise to its stabilization is determined from the condition at which t T.

The heating curve and cyclogram presented in FIG. 2 have the following characteristic points: - oil temperature in the crankcase - before carrying out a hot run-in; Јmim is the lower limit of the temperature value;

/

- the upper limit of temperature equal to the steady-state value, i.e.

 Max

oL max

The lower limit of the stabilization zone of the thermodynamic regime is determined from equation (1), at t T, e = 0.368 and Ј min 0.632.

According to the cyclogram, the switching of the device circuit occurs in the following order: at point 0, the engine starts up on the working process of hot running without load; at point I, the power supply system, ignition, coolant circulation is turned off and the crankshaft is forced to rotate from the electric drive of the stand; at point II, switching off the electric drive of the stand and putting the power, ignition, circulation, and coolant systems into operation.

During cyclic running in periods

forced rotation of crankshaft

T,

0

five

0

There is some compression load taking place on the shaft, which contributes to the process of adapting materials of rubbing pairs, as well as the possibility of monitoring and instrumental recording of the workability of ICE parts according to the parameters of stabilization of power loss due to friction, the graph NTp f (t) (figure 2).

The cyclic running-in of the internal combustion engine does not reduce the quality of the running-in parts, reduces the consumption of fuel and lubricants, and reduces the environmental pollution by the exhaust gases.

Claims (1)

Invention Formula The method of cyclic rolling in of an internal combustion engine, including cold running and subsequent hot running without load on the brake working stand, characterized in that, in order to reduce fuel and lubricants, hot running is carried out, in alternating cycles, each which includes the period of hot running without load and the subsequent period of forced rotation of the engine crankshaft for a time limited by the steady-state thermodynamic mode of the engine.