JPS58117328A - Engine, number of cylinder thereof is controlled - Google Patents

Abstract

PURPOSE:To prevent the temperature drop of a specific cylinder, and to obviate the abrasion of a piston while improving combustion in case of the restart of cylinders stopped by stopping each cylinder in approximately the same probability when controlling the number of cylinders. CONSTITUTION:The fuel injection valves 3a-3d of respective cylinder 5a-5d are controlled separately in response to injection timing signals 2a-2d from a control circuit 1. Injection timing signals 7a-7d are inputted to the AND gates 14a-14d of the control circuit 1, and load signals 11 are inputted to one terminals of OR gates 15a, 15b and cylinder select signals 12 to the other terminals through an inverter 16. The load signals 11 are at ''H'' when the load of the engine is high and at ''L'' when the load is low, and the cylinder select signals 12 are signals in which H and L are repeated with the revolution of a crank. Accordingly, the cylinders to be stopped are not limited in specific ones.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-cylinder engine that performs fuel injection, and more particularly to a cylinder number control engine that improves fuel economy by stopping a predetermined number of cylinders at a desired time.

When the engine is under low load, the fuel efficiency is improved by considering the entire load factor for each cylinder.For example, in the case of an 8-cylinder engine, the air direction number control engine improves fuel efficiency by focusing on the entire load factor of each cylinder. It is also known that there are methods that suspend 4 kiura, or in the case of 6 ki sho, those that suspend a specific 3 ki quotient.

However, in such a volume control engine, if a cylinder is brought to rest from an all-cylinder operating state, the rest of the cylinder will not be in a combustion state and will become cold.
This increases the frictional resistance of the piston, forcing the piston to bend.

In addition, when a state in which all cylinders are in operation is changed from a state in which the cylinders are inactive, there is a drawback in that good combustion cannot be expected because the cylinders in rest are in a cold state.

An object of the present invention is to provide an engine with controlled number of cylinders that prevents piston wear and delays complete combustion in each cylinder.

In order to achieve this object, the present invention is designed to stop each cylinder at approximately the same probability in order to prevent the temperature of only a limited number of cylinders from decreasing.

Hereinafter, the present invention will be explained in detail using Examples.

FIGS. 1 and 2 are diagrams showing an embodiment of a cylinder number control engine according to the present invention. In FIG. 1, each of the round teeth 5a to 5d of the 4-kilometer engine has intake pipes 4a to 4d.
4d, and exhaust vents 6a to 6d are connected. Intake pipe 4a
Fuel injection valves 3a to 3d are installed in each of the fuel injection valves 3a to 4d,
The fuel injection valves 3a to 3d are configured to inject fuel in accordance with fuel injection timing signals 28 to 2d, which are output signals from the control circuit 1.

The 4-cylinder engine outputs No. 16 according to the crank rotation angle, and this output is input to the injection timing creation circuit 8, and this injection timing creation time W! Fuel injection timing signals 7a to 7d, which are input to the control circuit 1, are outputted from r8.

In the control circuit Ml, as shown in FIG. 2, fuel injection timing signals 7a to 7d are connected to AND gates 14a to 14d, respectively.
It is designed to be input to the 1 input terminal of the . On the other hand, there is a load signal 11, and this load 1-11 is "H" when the engine load is high, and rLJ when it is low.
This is the signal. The load signal 11 is sent to the OR gate 15
The cylinder selection signal 12 is input to one input terminal of each of the OFL gates 15a and 15b, and the cylinder selection signal 12 is input to the input terminal of the OR gate 15H at the other input terminal of each of the OFL gates 15a and 15b. The cylinder selection signal 12' is inverted by the fc inverter 16 and is inputted to the input terminal of the cylinder selection signal 15b. As the crank rotates, the cylinder signal 12 changes to rHJ,
rLJ is a signal that is repeated.

The output of the OR gate 15a is the output of the AND gate 14a.
and 14C, and the output of the OR gate 15b is input to the other input terminals of the AND gates 14b and 14d. And each AN
New fuel injection timing signals 2a to 2 for driving the fuel injection valves 3a to 3d, respectively, are output from the D gates 14a to 14d.
d is output.

The operation of the cylinder number controlled engine configured in this way will be explained below using the flowcharts shown in FIGS. 3(a) and 3(b). When load store number 11 is rHJ, OR goo) 15
The outputs of a and 15b are rHJ9, and this signal and fuel injection timing No. 14 7a to 7d are input to ANI) gate 1.
The outputs 48 to 14d are the fuel injection timing signals 7a to 7d.
will be the same as

When the load signal 11 is rLJ, the cylinder selection signal 12 is output as the output of the OR (OR) 15a, and the O
A signal obtained by inverting the cylinder selection signal 12 is output as the output of the R gate 15b. Here, the cylinder selection signal 12 is “L”.
If J, then OR game) The output of 15b becomes “I(”,
AND gates 14b and 14d to which this signal is input
The output of is equal to the fuel injection timing 1 minus sign 7b+7d.

At this time, the output of the OR gate 15a becomes "L", and the outputs 2a and 2C of the AND gate 14al 14C to which this signal is input become rLJ. Further, the cylinder selection signal 12 is "HJit, etc., AND gate 14a.

Outputs 2a and 2C of 14c are fuel injection timing signals 7a.

It is the same as 7C, and the outputs 2b and 2d of 14b and 14d become rLJ.

In addition, Fig. 3(b) shows the crank rotation angle,
The cylinder selection signal 12 is sequentially inverted every time the crank rotates 7200 times.

In this way, the new fuel injection timing signals 2a to 2d that drive the fuel injection valves 3a to 3d are the negative # signals 11
When is at l'-HJ, it is exactly the same as the fuel injection timing signals 7a to 7d which are the outputs of the injection timing generation circuit 8. When the load signal 11 is rLJ and the cylinder selection signal 12 is rHJ, The fuel injection timing signals 7b and 7d'i are masked, and when the cylinder selection signal 12 is rLJ, the fuel injection timing 1 is set.
Negative 7a.

It will now mask 7C.

Therefore, since the cylinders that are inactive are not limited to specific cylinders, the temperature drop during half-cylinder operation becomes uniform for all cylinders. Therefore, by suppressing the circulation of coolant, the temperature of all cylinders can be maintained at a high temperature, and when a cylinder that is inactive is restarted, the condition of all cylinders becomes uniform, allowing normal operation. be able to.

In the embodiment described above, a pulse signal that is inverted every 720 degrees of crank rotation is used as the cylinder selection signal 12, but the present invention is not limited to this, and an M-sequence signal may be used.

An embodiment in this case will be described below with reference to FIG. 4. In the same figure, an M-sequence signal generator 21 is provided with a signal 7 at the time of fuel injection.
It has delay elements 30 to 39 into which a is input, and delay element 3
The output of 0 is sequentially input to the delay element 31, and the output of the delay element 31 is input to the delay element 32. and,
Each output of delay elements 32 and 39 is connected to EX-0 gate 2.
9, and the output of this EX-OR gate 29 is
The cylinder selection signal 12 is input to the self-retardation element 30 as well as the cylinder selection signal 12.
It can be extracted as .

Here, the M-sequence signal will be explained. Generally, the M series is represented by one characteristic equation. One of these characteristic equations is expressed by equation (1).

f(D)=I■D3■D1°-0・・・・・・・・・・・・
... (1) 1): Delay element ■ = Exclusive OR In other words, if there is a certain No. 1 signal, the exclusive OR of the signal delayed by 3 times and the signal delayed by 10 degrees. If you take , it becomes 0. This M-sequence signal has the following properties.

(1) The period is (210-1)Δt. Here, Δt is the delay length of the delay element.

(2) r The length of time for HJ level to take TH
Assuming that the length of time during which the "L" level can be reached is TL, then TnTL=TΔt. The average of the M-sequence signal is 1 for "H" and 1 for rL.
If J is set to 0, then

FIG. 5 shows the shape of a general M series. Also, the most characteristic feature of the M series is that its autocorrelation function maintains a constant value within a - period and is completely uncorrelated within a - period. Furthermore, the period of the M sequence is long (2''-1)Δt, and if considered ignoring the period, it can be considered to be a phaseless PA/i: No. 11.It is a cyclic signal, white noise. Furthermore, when the li number t is 1≦t≦10, there always exists a K such that 1■D'=DK.

In this case, no problem will occur if all the cylinders show exactly the same combustion state, but if there is a difference in the combustion state of each cylinder, that is, if only one cylinder has poor combustion, or if only one cylinder shows the same combustion state, then no problem will occur. If only the cylinder has too good combustion,
The combustion state changes depending on whether the cylinder selection signal 12 is turned on or off, and it is possible to prevent the crank from periodically vibrating once every four rotations. Since periodic vibrations are caused by the periodicity of the cylinder selection signal, the periodicity of the cylinder selection signal is eliminated as in the above embodiment.

That is, by randomly selecting cylinders using the M series signal as the cylinder selection signal 12, the operation
It is possible to randomly cause changes in the operating state of the engine due to variations in the combustion state and differences in the combustion state, eliminate periodicity, and completely avoid engine resonance.

In addition, since the average value of the M-series signal is 1/2, engine cylinder selection is performed with the same probability for all cylinders, so the hood reduction of the idle cylinders is biased toward one cylinder. Therefore, all cylinders exhibit a uniform temperature distribution.

As is clear from the above description, according to the cylinder number controlled engine according to the present invention, piston wear can be prevented and complete combustion can be achieved in each cylinder.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams showing an embodiment of the cylinder number control engine according to the present invention, FIG. 3 is a flowchart showing the operation of the cylinder number control engine, and FIG. 4 is a cylinder number control engine according to the present invention. An explanatory diagram showing another example of M
FIG. 5 is a diagram showing the sequence signal generation circuit, and is a diagram showing the shape of the M sequence. 1...Control 1u path, 2a-2d...M signal during fuel injection, 3a-3d...Fuel injection valve, 4a-4d...Intake pipe, 5a-5d...Cylinder, 6a-6d ...Exhaust pipe, 11...(10) Load signal, 12...Cylinder selection No. 16, 14a to 14d
...AND gate, 15a-15b...OR gate, 16...inverter, 21...signal generated in M series 1, (11) 11th/1 pole 2 sentinel 3V (0-) d /2

Claims (1)

[Claims] 1. In an internal combustion engine in which each cylinder has an intake pipe in which a fuel injection valve for supplying fuel is installed, the fuel injection of the fuel injection valve is controlled independently for each cylinder, and when the engine is under no load. and an engine that controls the number of cylinders in which the fuel supply to some cylinders is cut off when the load is low, and the fuel supply is cut off for each cylinder so that all cylinders are on standby.