JPS6320839Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a sound insulation device for a variable cylinder engine. The present invention relates to a sound insulation device for a variable cylinder engine that prevents noise from blowing back into the intake manifold caused by a shift in the timing of stopping the operation of an exhaust valve from leaking outside.

In recent years, in multi-cylinder engines, the fuel supply to some cylinders is cut off when the engine is running at low speeds and under light loads, and the intake and exhaust valves of those cylinders are stopped to reduce the number of operating cylinders, thereby reducing fuel consumption in the light load range. Improvements have been put into practical use.

However, in a variable cylinder engine such as the one described above, when the intake and exhaust valves are stopped and operated individually, the exhaust valve closes and stops when switching from the operating state to the stopped state, and the intake valve is still closed. During operation, as soon as the intake valve opens, the compressed air in the cylinder flows back into the intake pipe and expands.
This has the disadvantage that it generates a loud blowback sound that makes the driver and passengers feel uneasy and makes people around them feel uncomfortable. In addition, this blowback sound also occurs when the stopped cylinder is activated, with the intake valve opening first and the exhaust valve being closed and stopped.

The purpose of this invention is to eliminate the above-mentioned conventional drawbacks and provide an excellent sound insulation device that can suppress the generation of intake blowback noise when changing the number of operating cylinders in a variable cylinder engine.

The sound insulation device for a variable cylinder engine of this invention that achieves the above object is provided with an intake cutoff valve, a fuel supply cutoff device, and an intake/exhaust valve operation stop device for some cylinders, and when transitioning to reduced cylinder operation, is equipped with a cylinder number controller that operates the fuel supply cutoff device, intake cutoff valve, and intake/exhaust valve operation stop device in this order, and operates in the reverse order when shifting to all cylinder operation. It is characterized by

Embodiments of this invention will be described below with reference to the drawings.

FIG. 1 is a schematic plan view of a V-type 10-cylinder variable cylinder engine 1, where 4 indicates a constantly operating bank, and 5
indicates a bank that can be deactivated. 2 is an intake manifold, and 3 is an exhaust manifold.

In this invention, an intake cutoff valve 10 is installed upstream of the intake manifold 2A of the stoppable bank 5 of the V-type engine 1. This intake cutoff valve 1
0 may be the same as the intake cutoff valve 6 that cuts off the intake path when the engine 1 uses an exhaust brake (not shown), and its structure is, for example, as shown in FIG. 2.

That is, the intake cutoff valve 10 has a valve body 12 inside its casing 11 as shown in FIG.
3, and the holding member 13 is rotatably held by the rotating shaft 1.
4 is connected to a lever 15 outside the casing 11, and when the lever 15 rotates, the valve body 12
It is sufficient if it opens and closes the intake passage 18.

Also, as shown in Figure 3, the engine is 6 in series.
If cylinder engine 7 has #1 to #3 cylinders that can be deactivated, the intake manifold 8 is
It is sufficient to separate the valves and install the same intake cutoff valve 10 only on the upstream side of the intake manifold 8A of the #1 to #3 cylinders, and the operation can be stopped in the same manner as described above in other types of variable cylinder engines. Only the intake manifolds of the cylinders are assembled together, and an intake cutoff valve is installed on the upstream side.

Figure 4 shows the intake cutoff valve 10 installed as described above.
1 is a configuration diagram of an embodiment of a sound insulation device for a variable cylinder engine of this invention, including: FIG. A lever 15 for actuating the valve body 12 of the intake cutoff valve 10 is connected to a control cylinder 17 via a control wire 16 in this embodiment. When the high pressure air stored in the air tank 19 is introduced by turning on the solenoid valve 24, the control cylinder 17 rotates the lever 15 via the control wire 16 and closes the intake passage 18 by the valve body 12. It is composed of

Further, in FIG. 4, reference numeral 21 denotes a fuel injection pump, and a solenoid valve 23 is provided in the middle of an oil feed pipe 27 that connects the fuel injection nozzle 26 of the deactivatable cylinder. The fuel supply to the area has been cut off.
Furthermore, in this embodiment, the intake of the fuel supply stopped cylinder,
Hydraulic tappet 22 to stop exhaust valve 28
is provided, and when the oil supply to the hydraulic tappet 22 is stopped by turning on the solenoid valve 25, the suction and exhaust valves 28
has started to stop working.

Signals A, B, and C are input to the solenoid valves 23, 24, and 25 from the cylinder number controller 20, respectively.
It is designed to turn on and off depending on B and C. FIG. 5 is a waveform diagram of the signals A, B, and C, showing the on/off timing. In this invention, when the cylinder number controller 20 shifts from full cylinder operation to reduced cylinder operation, an on signal A is first inputted from the cylinder number controller 20 to the solenoid valve 23, and fuel is cut off to cylinders that can be deactivated. Next, the ON signal RO is input to the solenoid valve 24, and the intake cutoff valve 1 is turned on.
0 closes to cut off air intake to the cylinder to which fuel supply has been stopped. Finally, the ON signal C is input to the solenoid valve 25, and the intake and exhaust valves 28 are stopped.

Conversely, when shifting from reduced-cylinder operation to full-cylinder operation, the off signal from the controller 20 is input to the solenoid valve 25, solenoid valve 24, and solenoid valve 23 in this order as shown in FIG. , exhaust valve 2
8 returns to operation, then the intake passage 18 is opened, and finally the fuel supply is resumed.

Therefore, in the variable cylinder engine equipped with the sound insulation device of this invention, even if blowback noise is generated in the direction of the intake manifold due to a difference in the timing of stopping the intake and exhaust valves when the number of cylinders is changed, the intake air is always shut off when the noise occurs. Since valve 10 is closed, no blowback noise can escape out of the intake manifold.

As explained above, in this invention, an intake cutoff valve is provided upstream of the intake manifold of the cylinder that can be deactivated in a variable cylinder engine, and when the number of activated cylinders is changed, this intake cutoff valve is used to close the intake and exhaust valves of the cylinder to which fuel supply is deactivated. By configuring the intake and exhaust valves to close before operation stops and open after the intake and exhaust valves return to operation, it is possible to prevent intake blowback noise that occurs when changing the number of operating cylinders in a variable cylinder engine from leaking to the outside.
This has the effect that the driver can safely drive a vehicle equipped with a variable cylinder engine.

Although the valve body 12 of the intake air cutoff valve 10 is a butterfly valve in this embodiment, it may be of a sliding type, and any type of valve may be used as long as it can shut off the intake passage. Furthermore, although the intake cutoff valve is installed upstream of the intake manifold of the cylinder whose operation can be stopped, it may be installed inside each intake port.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view of a V-type 10-cylinder variable cylinder engine with the sound insulation device of this invention installed, and Fig. 2A is a side view of an embodiment of the intake cutoff valve of this invention. B is a sectional view taken along line MM of A; FIG. 3 is a schematic plan view of an in-line six-cylinder variable cylinder engine showing another embodiment of this invention;
The figure is an explanatory diagram showing the configuration of the sound insulation device of this invention, and FIG. 5 is a waveform diagram showing the control output of the controller of FIG. 4. 1,7...Engine, 2,2A,8,8A...
Intake manifold, 3, 9...Exhaust manifold, 4
... Constantly operating bank, 5 ... Operation stoppable bank, 6, 10 ... Intake cutoff valve, 11 ... Casing, 12 ... Valve body, 14 ... Rotating shaft, 15 ... Lever, 17 ... Control cylinder ,18,2
3, 24...Solenoid valve, 19...Air tank, 20
... Controller, 21 ... Fuel injection pump, 2
2...Hydraulic tappet.

Claims (1)

[Scope of utility model registration request] Some cylinders are equipped with an intake cutoff valve, a fuel supply cutoff device, and an intake/exhaust valve operation stop device, and when shifting to reduced cylinder operation, the fuel supply cutoff device, intake cutoff valve, intake/exhaust valve operation stop device, 1. A sound insulation device for a variable cylinder engine, comprising a cylinder number controller that operates in the order of the valve operation stop device, and operates in the reverse order when shifting to all-cylinder operation.