JPS58197446A - Cylinder number control engine - Google Patents

Abstract

PURPOSE:To prevent fluctuation of rotation and vibration at the start, by switching suction in accordance to the shift position of the speed change gear for cylinder number control engine for a car associated with an automatic speed change gear thereby maintaining the idle rotation constant. CONSTITUTION:A bypath 17 and a solenoid valve 18 are provided on a throttle valve 2 in the suction path of an engine comprising the stop side cylinders D-F which will stop under low load or idling and operating side cylinders A-C functioning continuously. A control circuit 15 will receive the shift position of an automatic speed change gear together with various operating state signals of engine from a sensor 14 to close the fuel injection valves d-f in the stop side cylinder at the idling while to open the solenoid valve 18 thus to increase suction when the speed change gear is in the drive range and to close the solenoid valve 18 when it is in the neutral or parking position. Consequently it causes no abrupt drop of rotation resulting in smooth starting.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a cylinder number control engine that performs partial cylinder operation by suspending the operation of some cylinders in a light engine load range or the like.

Generally, fuel efficiency tends to improve when an engine is operated under a high load. Therefore, in a multi-cylinder engine, fuel supply to some cylinders is cut to stop operation when the engine load is low. An engine with controlled number of cylinders was devised that relatively increases the load on the remaining active cylinders by this amount and improves overall fuel efficiency in the light load range.

(4! 1977-37581. Patent application 1977-30729
etc.) In this type of engine previously proposed by the present applicant.

As shown in Fig. 1, the operating cylinders A-C and the idle cylinders D
-F, the intake passage 1 is divided downstream of the throttle valve 2 into an operating side intake passage 3 and a rest side intake passage 4, and an exhaust passage 5
It is also divided halfway into an active side exhaust passage 6 and a rest side exhaust passage 7.

When the operation of cylinders D-F is stopped in the light load range of the engine, for example, the intake air amount signal from the intake air amount needle 8 and the rotation speed signal from the ignition coil (not shown) are used to stop the operation of cylinders D-F. When the load falls below a predetermined value, the control circuit 9 activates the fuel injection valve d corresponding to the cylinder D-F.
-fi is kept fully closed, the fuel supply t-a is cut off, and the cut-off valve 10t provided at the upstream part of the idle side intake passage 4 is closed;
At the same time, the valve 12 of the circulation passage 11 that connects the downstream side of this cutoff valve 1O and the idle-side exhaust passage 7 is opened to partially recirculate the exhaust gas to the idle-side cylinders DF.

As a result, partial cylinder operation is performed by operating only the active cylinders A to C while reducing the pumping loss in the idle cylinders D to F.

Further, even when the throttle valve 2 is fully closed and the engine is idling when the load rotational speed is both K and J-, partial cylinder operation is performed in the same manner (it may also be performed during deceleration).

However, in order to keep the engine output the same as when operating all cylinders during one partial cylinder operation, the operating side cylinders A-C are controlled in the control circuit 9.
The injection constant of the injector a''-c corresponding to the injector is changed to approximately twice that of the injector a''-c.

By the way, when such an engine is installed in a vehicle with an automatic transmission, which is becoming increasingly common these days.

Is partial cylinder operation performed during idle link?

,,,,-・□ For example, if you try to start from this state and change the shift position of the automatic transmission from Park or Neutral to Drive range, the idle intake air 1 (air mixture amount) will be maintained constant. , the rotational load of the torque converter is applied to the engine, resulting in a sudden drop in idling rotation speed. In addition, the long interval between explosions between active cylinders tends to increase rotational fluctuations, resulting in a problem of poor drivability when starting the engine.

This invention was made with a focus on these problems, and it detects the shift position of an automatic transmission and increases the idle intake amount when in drive range compared to the idle intake amount when in neutral or parking. An object of the present invention is to provide an engine with a controlled number of cylinders which solves the above-mentioned problems by maintaining a stable idling rotation speed regardless of shift change.

The present invention will be explained below based on the drawings. The positions of the cylinders 2A-C and the cylinders D-F on the idle side, where the fuel supply is cut off and the operation is stopped (combustion noise is stopped) in the light load range or during idling, have been swapped with those in Figure 1.

In the figure, 3 is an intake passage on the operating side, 4 is an intake passage on the idle side, 6 is an exhaust passage on the operating side, 7 is an exhaust passage on the idle side, and 10 is a cutoff valve that closes when the operating body is stopped.11 is normally on the idle side when the operating body is stopped. A circulation passage that recirculates part of the exhaust gas to cylinders D-F is shown.

An automatic transmission 13 is connected to the output shaft of this engine, and a position sensor 14 is provided on the side of the transmission 13 as means for detecting a shift position.

The position sensor 14 uses a switch that closes when in the shift position or in the drive range, and opens when in neutral or parking, and its detection signal is the intake air amount signal from the intake air pointer 8 that detects the operating state of the engine. 1. The rotation speed signal is sent to the control device 15 together with a rotation speed signal from an ignition coil (not shown).

In addition, the throttle valve opening sensor 1 is configured to detect the opening sound of the throttle valve 2.
6 is provided, and this detection signal is also sent to the control device 15.

On the other hand, as a means for switching the idle intake amount during idling when the throttle valve 2 is fully closed, an auxiliary passage 17 is formed that bypasses the throttle valve 2 and guides the intake air. A valve 18 is interposed. The auxiliary passage 17 has a passage area set so as to introduce a predetermined amount of intake air, as will be described later, and the solenoid valve 18 is controlled to open and close according to a command from the control device 15, and opens when excited.

The control device 15 determines based on each of the detection signals in a light load range where the load is small compared to the engine rotational speed and during idling when the throttle valve 2 is almost fully closed.

A command to fully close the fuel injection valve d-f corresponding to the inactive cylinder D-F is issued, and fuel is supplied t'! Definitely that work wJ
t Pause. At the same time, the shutoff valve 10t of the intake passage 4 on the idle side is closed, and the valve 12 of the circulation passage 11 is opened to recirculate a part of the exhaust gas to the cylinders D-F on the idle side to perform one-part cylinder operation.

On the other hand, the control device 15 during this idle link.

Based on the signal from the position sensor 14, if the automatic transmission is shifted to a drive range, the solenoid valve 18 of the auxiliary passage 17 is opened, and if the automatic transmission is in neutral or parking, the solenoid valve 18 is closed. As a result, the idle intake air amount is changed according to the shift position.The injection amount from the fuel injection valves a-c, d-f is controlled by the control device 15, and is controlled by the intake air amount signal and the exhaust passage. In response to feedback signals from an oxygen sensor 19 provided downstream of the engine 5, each cylinder A to F is controlled to obtain an air-fuel mixture with an optimum air-fuel ratio.

In other words, when there is no load in neutral or parking, the throttle valve 2 closes completely and reaches its minimum opening.
(alternatively, an idle passage may be formed), a certain amount of intake air is introduced.

A predetermined idle link speed is maintained.

On the other hand, when the shift position is changed from neutral and parking to the drive range, four predetermined amounts of intake air are introduced from the auxiliary passage 17, and the output is increased accordingly.

Therefore, even if the shift position is put into the drive range when attempting to start from an idling state and the load of the torque converter is applied to the engine, as in the conventional example, a drop in rotation by one revolution is prevented, and the introduced air is prevented from dropping by one revolution. −
Correspondingly, the number of revolutions a is maintained at approximately the same value as the predetermined idling number of revolutions such as when the engine is in Utral mode.

As a result, there is no need to worry about an increase in main rotational fluctuations during one partial cylinder operation, and it is possible to stably maintain one rotational speed at one engine-like lI' and smoothly perform one start.

FIG. 3 shows another embodiment of the present invention, in which a carburetor 20't- is used as a fuel supply device and is applied to a four-cylinder engine.

In this case, in the @load range, etc., the opening operation of the intake and exhaust valves (not shown) of the cylinders on the idle side and H is regulated and closed to cut off the fuel ring supply tm and cause one partial cylinder operation sound. However, this means for regulating the opening operation of the intake and exhaust valves is well known and will not be described here.

Further, 13 is an automatic transmission, 14 is a shift position sensor, 1
5 indicates a control device.

As a means for switching the idle intake air amount according to this shift position, as shown in FIG.

An auxiliary passage 24 is formed by bypassing the venturi part 21 and throttle valves 22 and 23 of the carburetor 20, and a solenoid valve 25 for opening and closing the auxiliary passage 24 is interposed in the middle of the auxiliary passage 24, and a float is provided on the upstream side of the solenoid valve 25. A fuel boat 26 is open, communicating with a chamber (not shown).

The solenoid valve 25 is opened by a command from the control device 15 when the automatic transmission 13 is in the drive range during idle link. At this time, the auxiliary passage 24
The shapes of the fuel yN-) 26 and the like are set so that a predetermined amount of intake air is introduced from the fuel tank and a mixture with an optimum air-fuel ratio is obtained.

According to this, as shown in FIG.
1 is not necessary, and since it is a vaporizer type, the structure is simple and control is easy.

Reference numeral 27 in Figure 1 is a switch that connects the ignition current from the ignition coil 28 to the cylinder on the idle side via the distributor 29 to the ignition plug (not shown) at E, and is opened during partial cylinder operation to save power.

FIGS. 5 and 6 show other embodiments of the present invention.

Instead of forming the auxiliary passage 24, the throttle valve 23 is configured to open somewhat to switch the idle intake air amount.

In this case, for example, a diaphragm device 31 is connected to the valve shaft of the throttle valve 23 through a hair screw 30t, and when the idle intake amount is increased, the diaphragm device 31 is switched to the three-way solenoid valve 32' and the diaphragm device 31 is connected to the engine suction negative pressure. Introducing the throttle valve 23
Open to the specified opening.

When reducing the intake air amount at idle, atmospheric pressure is introduced into the diaphragm device 31, the hair screw 301 is opened, and the throttle valve 23 is fully closed (minimum opening degree is ensured).

These controls are of course carried out by the control device 15 in response to signals from the position sensor 14, etc., and the idle link rotational speed can also be maintained stably in this manner. However, in this case, a sensor or the like that detects the state of the vehicle being stopped (vehicle speed is 0) may be provided in place of the sensor that detects the idle link state sound.

In addition, as shown in FIG. 7, a lever 33 is attached to the valve shaft of the throttle valve 23, and an actuator such as the lever 33rC diaphragm device 31 is connected to the lever 33 to selectively introduce negative pressure from the vacuum tank 34. It can also be controlled in the same way.

As explained above, according to the present invention, in a cylinder number control engine installed in a vehicle with an automatic transmission, the shift position of the automatic transmission is detected, and the shift position [dE neutral] is determined during idle link of parking. The idle intake amount is switched between the idle link and the idle link of the drive range, so that the engine rotation speed TL remains constant regardless of the shift position. This has the effect of preventing engine failure, maintaining a good engine condition, and ensuring smooth starting performance and engine performance.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional example, Fig. 2 is a cross-sectional view of an embodiment of the present invention, Fig. 3 is a schematic cross-sectional view of another embodiment of the present invention, and Fig. 4 is a summary thereof. 5 and 6 are partial sectional views showing other embodiments of the present invention, and FIG. 7 is a partial sectional view showing another embodiment of the present invention. 1... Intake passage, 2... Throttle valve, 8... Intake air amount needle. 13... automatic transmission, 14... position sensor, 15...
...Control device, 16... Throttle valve opening sensor, 17...
Auxiliary passage, 18... Solenoid valve, 20... Carburizer, 22
．． 23... Throttle valve. 24...Auxiliary passage, 25...Solenoid valve, 26...Fuel bow 32...Three-way H forcep valve. Patent applicant: Nissan Motor Co., Ltd. Figure 3-275- Figure 4

Claims (1)

[Scope of Claims] A cylinder on the idle side whose fuel supply is cut off and its operation is suspended in a light load range of the engine or when the engine is idling. In a multi-cylinder engine for a vehicle, which is equipped with an active cylinder that is constantly supplied with fuel and fresh air and continues to operate, and which is connected to an automatic transmission on an output shaft, a membrane above the means for detecting the shift position of the automatic transmission is provided. The number of cylinders is characterized by being provided with a means for switching the idle intake amount so that the engine speed is approximately the same when the shift position is in idle link in neutral or parking and in idle link in drive range. control engine.