JPS62162720A - Piston type engine with improved fuel consumption rate in operation with low load - Google Patents

Abstract

PURPOSE:To improve a fuel consumption rate in operation with a low load, by providing a plurality of sub-chambers at the upper portion of a cylinder and attaching nozzle to each of the sub-chambers for injecting fuel of which amount is sufficient to burn in a good condition into the sub-chambers. CONSTITUTION:A cylinder head 2a is provided with 2 recessed sub-chambers 4a, 4b, each of which having a nozzle 5 and an ignition plug 6 disposed in it. When a piston 1 moves downwardly, air is introduced into a cylinder 2 through a suction valve and when the piston 1 moves upwardly, the air is compressed. Around the time when the compression is completed, a nozzle 5 having an opening in the sub-chamber ejects a suitable amount of fuel, which is ignited by the plug 6. With such an arrangement, a fuel consumption rate is prevented from being deteriorated in operation with a low load.

Description

[Detailed Description of the Invention] A. Purpose of the Invention (Field of Industrial Application) This invention provides a method for reducing fuel consumption during low load operation in piston type engines such as gasoline engines and diesel engines. This invention can be used to prevent the I rate from deteriorating.

(Prior art) Piston type engines such as gasoline engines and diesel engines, especially gasoline engines.

It is known that the fuel consumption rate increases during low load operation.

For example, in an engine that consumes 220 gr/tPhr of gasoline during normal operation, the rotational torque is normally Og.
The fuel consumption rate increases as r/lf'hr. The reasons for this are: (1) During normal operation, the suction pipe pressure is reduced to -400 to -500 mHg, as the valve is throttled to reduce both air and fuel by 0 to 50 mm, which lowers the atmospheric pressure. Applying a brake by pushing against the downward movement of the piston.

(2) In normal operation, the air-fuel sink (input = 1 in the case of stoichiometric mixture ratio) is in the range of 1 to 0.9, whereas in the case of low load, due to the characteristics of the carburetor, When the fuel input becomes 0.7 or less, excessive fuel is consumed.

It is believed that this is because of

A similar trend exists in diesel engines.

The present inventor has proposed that, as a means of preventing the deterioration of the fuel consumption rate at low loads as described above, in a multi-cylinder engine, the fuel supply to some engines may be stopped or the fuel supply may be intermittent. invented a multi-cylinder engine in which the engine output is reduced but the combustion state of the fuel within the cylinders remains unchanged. (Patent application filed on December 28, 1985) (Problems to be solved by the invention) As mentioned above, the fuel consumption rate of conventional piston type engines deteriorates at low loads. The present invention aims to provide a new type of piston type engine that improves this point.

In particular, in the earlier version of E, a part of the engine cylinder was stopped during operation without burning any fuel, so there were concerns about vibrations, etc., but the present invention solves this concern. This was an attempt to create a piston-type engine that could be used as a single-cylinder engine.

Structure of the Invention (Means for Solving Problems) In principle, the piston type engine of the present invention, as schematically illustrated in FIG.
The suction and compression of air 3 into the engine are performed in the same way as during normal operation during low-load operation, and the fuel is reduced and supplied according to the decrease in load, and only a portion of this air (the shaded area) is used. The air is then ignited to create a combustion explosion at a good air-fuel ratio, and the remaining air is exhausted without taking part in the combustion, thereby reducing the generated power and ensuring good combustion. A plurality of auxiliary chambers are recessed into one or both of the inner surfaces of the cylinder head, and a nozzle is installed in each auxiliary chamber to inject fuel into the auxiliary chambers in an amount that is well-combusted by the air that is forced into the auxiliary chambers when the piston rises. It is characterized in that it is attached and controls the use or non-use of a plurality of nozzles in accordance with the magnitude of the load.

With this structure, air is sucked into the cylinder by the piston movement and compressed in the same way as during normal operation even during low loads, and by changing the number of operating nozzles depending on the degree of load, In some cases, the above-mentioned problems are solved by reducing the amount of fuel used to reduce the power generated and improving combustion to eliminate wasted fuel.

(Function) Air is sucked into the cylinder and compressed uniformly regardless of the load.

Fuel is supplied by injection into the auxiliary chamber. The fuel injector is designed to burn at a good air-fuel ratio due to the air in the pre-chamber. The compressed air in the other auxiliary chambers to which fuel is not injected is not supplied with fuel and therefore does not participate in power generation. This allows generation of low torque that corresponds to low loads.

Combustion takes place in the pre-chamber at a good air-fuel ratio.

Near the boundary between the fuel supply area and non-fuel supply area, there is only one fuel per cylinder (I+<-h), which is traced to t. can.

The engine of the present invention configured as described above has a number of auxiliary chambers provided on the upper surface of the piston, the inner surface of the cylinder head, etc.
Partial combustion can be carried out in several stages and can be used in both single-cylinder and multi-cylinder engines.

(Example) ': fI, Figure 2 shows two sub-chambers 4 in the cylinder head 2a.
An example of a gasoline engine is shown in which a and 4b are recessed and a fuel injection nozzle 5 and a spark plug 6 are provided therein, respectively.

When the piston 1 moves down, air is sucked into the cylinder z through an intake valve (not shown), and when the piston 1 moves up, this air is compressed. At the end of compression, a nozzle 5 opening into the auxiliary chamber 4a injects a suitable amount of gasoline, and a plug 6 ignites it. The combustion gas spreads to the upper part of the cylinder as the piston descends, and together with the compressed air, pushes down the entire surface of the piston, so there is little concern that the piston will not be compressed unevenly or that vibration will occur.

The volume of the auxiliary chamber 4a is set so that the amount of air therein achieves an air-fuel ratio suitable for burning the injected gasoline, so the power obtained by this combustion explosion simultaneously burns the two combustion chambers 4a and 4b. Uses a good combustion rate of consumption,
Can handle low loads.

Combustion in this case is carried out only by the air in the auxiliary chamber 4a, and the air compressed in the other auxiliary chamber 4b does not participate in the combustion. As mentioned above, combustion takes place when gasoline is diluted, but the amount is so small that it has almost no effect.

FIG. 3 schematically shows a ρυ diagram for a gasoline engine (Otto cycle). A solid line 7 shows an adiabatic expansion line when both subchambers 4a and 4b are used simultaneously, and a dotted line 8 shows an adiabatic expansion line when only one subchamber 4a is used.

FIG. 4 schematically shows a ρυ diagram for a diesel engine (diesel cycle), and the solid line 7 and dotted line 8 are the same as in FIG. 3.

FIG. 5 shows subchambers 4a and 4 recessed in the upper surface of the piston l.
The upper part of the cylinder of a gasoline engine provided with b is schematically shown,
An injection nozzle 5 and a spark plug 6 are sunk in the cylinder head 2a above each sub-chamber. In the case of a diesel engine, the spark plug 6 is not necessary.

In FIG. 6, a cylinder head 2a is provided with auxiliary chambers 4a and 4b that are inclined outward from the cylinder, and a nozzle 5. An example in which a plug 6 is attached is schematically shown.

FIG. 7 shows a subchamber 4a on the upper surface of the piston as in the example of FIG.
, 4b are recessed, and the auxiliary chambers 4a, 4 can be operated without wasting fuel.

Figure 8 also shows an engine with four subchambers, and in any type of engine, the air that is forced into one subchamber and the fuel injected into it are combusted at a good air-fuel ratio. Because I decide to do it.

Even if the load is reduced, fuel will not be wasted unnecessarily.

Although a single cylinder engine has been described above, in the case of a multi-cylinder engine, various types of low-load operation can be accommodated by using various combinations of subchambers.

Figure 9 shows the ρ of the Otto cycle when three subchambers are provided.
Figure 10 shows the solid line 7 in the case of full load.
The figure shows the ρυ diagram of the diesel cycle.

FIG. 12 schematically shows an example in which two sub-chambers 4a and 4b are provided in each cylinder in a six-cylinder engine. The unused sub-chamber 4b is combined.

Similarly, FIG. 13 schematically shows the number of unused subchambers (8) out of the three subchambers 4a, 4b provided in each cylinder.

In this way, by combining the numbers of used sub-chambers and unused sub-chambers in various ways, fuel can be combusted at a good air-fuel ratio under various types of low loads, and low-load operation can be performed without wasting fuel. I can do it.

The use or non-use of the auxiliary chamber can be automatically controlled by a computer or the like according to a predetermined combination pattern by detecting the magnitude of the torque, depending on the magnitude of the load.

8. Effects of the invention (1) Since a plurality of auxiliary chambers are provided in the upper part of the cylinder, and fuel is injected into the air compressed into these chambers for combustion, the magnitude of the load will vary depending on the number of auxiliary chambers used. It is possible to generate power in response to the

(2) Each pre-chamber is equipped with a nozzle that injects t of fuel that can perform proper combustion with the air compressed into the pre-chamber, so good combustion is always achieved regardless of the number of pre-chambers used. I can make you do it.

(3) Therefore, even when the load is low, the fuel consumption rate does not deteriorate.

(4) Even if only a part of the auxiliary chamber is used, the gas pressure is evenly applied to the entire upper surface of the piston, so there is no need to worry about the piston descending smoothly or causing vibration.

(5) Can be used for both m-cylinder engines and multi-cylinder engines.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical sectional view of the upper part of a cylinder for explaining the principle of the present invention, and FIG. 2 is a longitudinal sectional view of the upper part of a cylinder of a gasoline engine, schematically showing an example in which the cylinder head is provided with two auxiliary chambers. Figure 3 is a ρV diagram for a gasoline engine, and Figure 4 is a ρV diagram for a gasoline engine.
The figure is a ρV diagram for a diesel engine, Figure 5 is a schematic vertical cross-sectional view of the upper part of the cylinder with two auxiliary chambers provided above the piston, and Figure 6 is a cylinder head inclined outward. 7 is a schematic plan view of a piston with three subchambers, and FIG. 8 is a schematic plan view of a piston with four subchambers. Figure 9 is the ρυ diagram of the Otto cycle, and Figure 10 is the ρυ diagram of the Sabate cycle.
Diagram, Figure 11 is the ρυ diagram of the diesel cycle, 1st
Figure 2 is a schematic plan view showing an example of the sub-chamber used in a 6-cylinder engine with two sub-chambers in each cylinder, and Figure 13 is a similar schematic plan view of one in which each cylinder has three sub-chambers. It is a diagram. 1: Piston, 2 Niji cylinder, 2a Niji cylinder head,
3: Air, 4a, 4b: Subchamber, 5: Nozzle, 6: Spark plug, 7: Solid line, 8.8a, 8b: Dotted line. Patent applicant Hitoshi Nishiwaki - Agent
Kinzo Koyama (and 1 other person) at diagram Figure 2 v
v? Figure s5 Figure 6 Figure 17 Figure 8 Figure 10 @ t2 Figure 4 Figure 13

Claims (1)

[Claims] A plurality of auxiliary chambers are provided that are recessed in one or both of the upper surface of the piston and the inner surface of the cylinder head, and a nozzle is provided in each auxiliary chamber to inject fuel into the auxiliary chamber in an amount that is well-combusted by the air that is forced into the auxiliary chamber when the piston rises. A piston-type engine with improved fuel consumption during low-load operation, which is attached to the pre-chamber and controls the use or non-use of multiple nozzles depending on the size of the load.