JPS636426Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an operation display device for an exhaust turbo supercharger.

In the exhaust turbo supercharger attached to an internal combustion engine, the exhaust gas from the internal combustion engine rotates the turbine, and the compressor directly connected to the turbine is also rotated to compress air and send it to the intake side of the internal combustion engine. I'm trying to increase boost pressure.

By the way, some internal combustion engines equipped with an exhaust turbo supercharger are equipped with a boost meter, but this boost meter is not suitable for high-speed,
It detects the boost state under high load and issues a warning if it is low.The normal boost pressure of the exhaust turbocharger depends on the rotational speed and load of the internal combustion engine, so this The driver cannot judge from the boost meter display whether the current boost pressure is normal or not. In other words, the operating conditions in which the boost meter operates are extremely rare and cannot be determined under normal operating conditions.

Additionally, in the event that the exhaust bypass system malfunctions and an overboost condition occurs, warning devices are currently installed to notify the user of this condition, and Q-throttle devices are also installed, but these are also used when the internal combustion engine is running at high speeds and under high loads. It is only useful.

Therefore, there is currently no way to notify the driver of a decrease in boost pressure due to performance deterioration of the exhaust turbocharger under normal operating conditions, that is, to notify the time for maintenance of the exhaust turbocharger.

The present invention was developed in view of the above-mentioned circumstances, and its purpose is to compare the actual boost pressure in an internal combustion engine equipped with an exhaust turbo supercharger with the normal boost pressure depending on the operating condition. The object of the present invention is to provide a display device that can display whether the current value is high, low, or appropriate.

Next, one embodiment of the present invention will be described in detail using the drawings.

FIG. 1 is a block diagram of a supercharger operation display device according to the present invention. In the figure, 1 is an engine;
11 is an exhaust pipe, 12 is an intake pipe, 2 is an exhaust turbo supercharger, and 21 is its turbine, which is rotationally driven by the exhaust gas from the exhaust pipe 11. The compressor 22 is rotated through a shaft 23 and compressed air is sent to the intake pipe 12. 3
is an exhaust bypass device, 31 is a diaphragm, on one side of which atmospheric pressure is applied, and on the other side is a conduit 35.
The structure is such that boost pressure derived from the above is applied. 32 is a pressure spring that presses the diaphragm 31 against the intake pressure; 33 is a bypass valve that is actuated by the balance between the pressure spring and boost pressure; and 34 is a valve that exhausts exhaust pressure when the bypass valve 33 is actuated. This is a bypass path that allows the fluid to escape toward the mouth. 4 is a rotation detector that detects the rotational speed of the engine, 6 is a load detector that detects the load of the engine, and 7 is a pressure detection device that detects the boost pressure in the intake pipe 12. 8 is a control device, the detailed structure of which will be described later. Reference numeral 9 denotes a display device, which has three display sections, a yellow section 91, a green section 92, and a red section 93. Then, the control device 8 compares the normal boost pressure P calculated by the calculation device in the control device 8 according to the operating state of the engine 1 and the actual boost pressure P″ detected by the pressure detection device 7, and the latter Yellow category 91 when is higher than the former by +10% or more
lights up, a green segment 92 lights up in the range from less than -20% to less than +10%, and a red segment 93 lights up when it is less than -20%.

FIG. 2 is a block diagram showing details of the control device 8, in which 81 is an arithmetic circuit, 82 is an adder circuit,
83 is a subtraction circuit, and 84 is a comparison circuit. The boost pressure P of a normal exhaust turbocharged engine is
It depends on the engine rotational speed N and the load L, and can be expressed as P=f(N,L), but in an engine equipped with an exhaust bypass device, when the exhaust bypass device is activated, the above function does not necessarily change. may not be applicable, so the boost pressure corresponding to the engine speed N and load L is measured in advance when the exhaust turbocharger and the device including them are operating normally, and the arithmetic circuit 81 It may also be stored as map data. Figure 3 is a characteristic diagram showing the relationship between the boost pressure P and the rotational speed of an engine equipped with an exhaust turbo supercharger.The solid line shows the characteristic at full load, and the characteristic at 3/4 load is shown at one point. The characteristics at 2/4 load state are shown by the chain double-dashed line, and the characteristics at 1/4 load state are shown by the dotted line. The arithmetic circuit 81 calculates the normal boost pressure P every moment from the engine rotational speed N and the load L input thereto according to the above formula. The normal boost pressure calculated by this calculation circuit 81 is not calculated along the four lines shown in FIG. 3, but can be calculated at any value within the hatched area depending on the load condition. , furthermore, the engine speed is the intercept point rotation speed NI
When the boost pressure exceeds PI and reaches the full load state, the normal boost pressure saturates to the value PI and does not output any higher value. That is, in a full load state where the engine rotational speed is NI or higher, the exhaust bypass device 3 operates to bypass a portion of the exhaust gas flowing into the turbine 21 so that the boost pressure is constant. The addition circuit 82 always outputs a value Po that is 10% higher than the normal boost pressure output from the calculation circuit 81, and the subtraction circuit 83 outputs a value Po that is 10% higher than the normal boost pressure output from the calculation circuit 81.
Always 20 more than the normal boost pressure output from 1
Outputs a value Pu lower by %. The comparison circuit 84 compares the actual boost pressure P' detected from the intake pipe 12 of the engine 1 with Po, P, and Pu output from the arithmetic circuit 81, addition circuit 82, and subtraction circuit 83. When P' is greater than or equal to Po, a signal is output to the Y terminal, when P' is less than Po and greater than Pu, a signal is output to the G terminal, and when P' is less than or equal to Pu, a signal is output to the R terminal. is output.

Next, the operation of this invention will be explained.

Assuming that the engine 1 is rotating at a predetermined rotation speed, the engine rotation speed N is input to the control device 8, and the engine rotation speed N is estimated from the throttle opening of the gasoline engine or the ease position of the diesel engine. The load L is also input to the control device 8 . Arithmetic circuit 81 in control device 8
is the normal boost pressure P from the rotational speed N and load L.
is calculated from that map. On the other hand, the actual boost pressure P′ in the intake pipe of the engine is also measured by the comparison circuit 8 of the control device.
4 is input. The arithmetic circuit 81 captures the momentary changes in the rotational speed N and the load L, and calculates the normal boost pressure P at fixed short intervals, for example, every 50 ms.
If the engine and the attached exhaust turbo supercharger are operating normally, there will be almost no difference between the normal boost pressure P and the actual boost pressure P'.
A signal is output from the G terminal of the comparison circuit 84 of the control device 8, and the green section 92 of the display 9 lights up, indicating that the operating state of the turbocharger is normal. Furthermore, when the engine rotation speed exceeds the intercept point rotation speed NI and is operating under full load, the exhaust bypass device 3 malfunctions and the boost pressure cannot be controlled, resulting in the actual boost pressure P' When the boost pressure P becomes larger than the normal boost pressure P, and the excess exceeds 10%, a signal is output from the Y terminal of the comparison circuit 84 of the control device 8.
The yellow section 91 of the display 9 lights up to indicate that the boost pressure of the turbocharger cannot be controlled. Furthermore, if the exhaust turbo supercharger's bearing, turbine, compressor, etc. fail and the compression function of the exhaust turbo supercharger deteriorates, the actual boost pressure P' may become smaller than the normal boost pressure P. When the difference exceeds 20%, a signal is output from the R terminal of the comparison circuit 84 of the control device 8, and the red section 93 of the display 9 lights up, indicating that the function of the exhaust turbo supercharger has declined. do.

In the above embodiment, the functions of the exhaust turbo supercharger are displayed in different colors, but an acoustic display may be added using the signal output from the comparison circuit 84.

As explained in detail above, the present invention provides an arithmetic circuit that calculates the normal boost pressure from the rotational speed and load of the internal combustion engine, and a calculation circuit that calculates the normal boost pressure in an internal combustion engine equipped with an exhaust turbo supercharger. It has a comparison circuit that compares the actual boost pressure with the actual boost pressure, and is configured to display the operating status of the exhaust turbo supercharger using the output signal of the comparison circuit. In addition to being able to constantly monitor the operating status, if the turbo pressure control mechanism (exhaust bypass device) of the exhaust turbo supercharger breaks down or the exhaust turbo supercharger deteriorates and cannot operate as expected, Displays that prompt the driver to perform maintenance can be displayed even during normal driving conditions.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an internal combustion engine equipped with an exhaust bypass type exhaust turbocharger, FIG. 2 is a block diagram of a control device, and FIG. 3 is a characteristic diagram of the exhaust turbocharger. 1...Engine, 2...Exhaust turbo supercharger, 3
...Exhaust bypass device, 4...Rotation detector, 6...
...Load detector, 7...Pressure detection device, 8...Control device, 81...Arithmetic circuit, 84...Comparison circuit, 9
……display.

Claims (1)

[Scope of utility model registration request] It has at least an arithmetic circuit that calculates or stores the normal boost pressure from the rotational speed and load of the internal combustion engine, and a comparison circuit that compares the normal boost pressure with the actual boost pressure, and exhausts the air based on the output signal of the comparison circuit. An operation display device for an exhaust turbocharger, characterized in that the operation status of the turbocharger is displayed.