JP2000179349A - Negative-pressure engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal combustion engine which does not emit an air pollutant such as CO and NOx by using hydrogen as fuel. SOLUTION: Hydrogen and oxygen are respectively supplied into a cylinder 1 from a first intake valve 7h and a second intake valve 7c which are opened in an intake stroke. Thereafter, the mixture is ignited at the bottom dead center. As a result, the following reaction occurs: 2H2 (2 moles)+O2 (1 mole)→2H2O (2 moles). More specifically, the mixture of 2 moles of hydrogen and 1 mole of oxygen changes into 2 moles of water vapor. Since the resultant volume of water vapor is two-thirds of that of the original mixture, the atmospheric pressure within the cylinder 1 is also reduced to two-thirds, i.e., 2/3 atm. Therefore, in a compression stroke, a piston 2 is driven toward the top dead center by the negative pressure within the cylinder 1. An exhaust valve 8 is opened in the following exhaust stroke, whereby the water vapor within the cylinder 1 is emitted from the exhaust valve 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a negative pressure engine that operates by burning a mixture of hydrogen and oxygen.

[0002]

2. Description of the Related Art Conventionally, gasoline engines and diesel engines are generally employed as power sources for automobiles and the like. However, since gasoline engines and diesel engines use petroleum containing hydrocarbons as a main fuel, they not only emit CO and NOx, which cause air pollution, but also cause global warming and depletion of petroleum resources. There is a problem that causes. So in recent years,
Development of an electric vehicle using a battery and a motor as power sources has been advanced.

[0003]

However, the performance of an electric vehicle is greatly influenced by the performance of a battery. At present, it is not only difficult to extend the mileage per charge at a time, but also to improve the battery. Is very expensive, so that there is a problem that the price of the power unit including the battery rises significantly.

The present invention has been made in view of the above circumstances, and has as its object to provide an internal combustion engine that does not emit air pollutants such as CO and NOx by using hydrogen as a fuel.

[0005]

According to the first aspect of the present invention, a piston slidably fitted to a cylinder is connected to a crankshaft via a connecting rod. A negative pressure engine in which a piston is driven by a negative pressure generated by burning a mixture of hydrogen and oxygen inside a cylinder to rotate a crankshaft. The intake stroke in which a mixture of hydrogen and oxygen is sucked into the cylinder by a piston that moves from the bottom to the bottom dead center, and the volume when the mixture ignited near the bottom dead center burns to produce water vapor The piston is driven toward the top dead center by the negative pressure generated by the decrease, and the contraction / exhaust step of discharging the steam to the outside of the cylinder from just before the top dead center is sequentially performed. Negative pressure engine is proposed, wherein.

According to the above construction, a negative pressure is generated in the cylinder due to a reduction in volume when a mixture of hydrogen and oxygen is burned to generate steam, and the negative pressure drives the piston to drive the crankshaft. can do. The only product produced by combustion of the air-fuel mixture is water vapor or water, and there is no risk of polluting the environment because harmful CO and NOx are not generated.

According to the second aspect of the present invention,
In addition to the configuration of claim 1, a negative pressure engine is proposed, wherein the mixture has a mixing ratio of 1 mol of oxygen to 2 mol of hydrogen.

According to the above configuration, since the mixture has a mixing ratio of 1 mol of oxygen to 2 mol of hydrogen, the mixture is combined without remaining hydrogen or oxygen during combustion of the mixture, and the negative pressure after combustion is reduced. And the driving force can be increased.

According to the third aspect of the present invention,
In addition to the configuration of claim 1, a negative pressure engine is proposed, comprising six cylinders that operate continuously at every crank angle of 60 °.

According to the above configuration, the six cylinders are
Operates continuously at every crank angle of °, so any cylinder always generates driving force during one rotation of the crankshaft, preventing torque fluctuations of the crankshaft and enabling smooth rotation Can be

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 6 show an embodiment of the present invention. FIG. 1 is an overall structural view of an engine, FIG. 2 is an enlarged view of a cylinder head portion of the engine, and FIG. 3 is 3-3 in FIG. 4 is a sectional view taken along the line 4-4 in FIG. 2, FIG. 5 is an explanatory diagram of the stroke of the engine, and FIG. 6 is a diagram illustrating the operating state of six cylinders.

As shown in FIGS. 1 to 4, an engine E operating at a negative pressure generated by the combustion of hydrogen has a cylinder 1
The piston 2 is slidably fitted to the piston 2, and the piston 2 is connected to a crankshaft 4 via a connecting rod 3. The cylinder head 5 is provided with a combustion chamber 6 facing the upper surface of the piston 2, and first and second intake valves 7 h and 7 o and one exhaust valve 8 are provided so as to face the combustion chamber 6. . The combustion chamber 6
Unlike the combustion chamber of an ordinary internal combustion engine, is formed in such a shape that the volume almost disappears when the piston 2 reaches the top dead center.

Valve seats 9h and 9o on which the first and second intake valves 7h and 7o are seated are formed inside a pair of intake ports 10h and 10o formed in the cylinder head 5, respectively. (2) The intake valves 7h and 7o are moved downward and seated on the valve seats 9h and 9o, so that the intake valve holes 11
h, 11o is closed. The first and second intake valves 7h,
Valve stems 12h, 12o extending integrally from 7o are urged upward (in the valve opening direction) by valve springs 13h, 13o, and are pressed by intake rocker arms 14h, 14o operated by a valve operating mechanism (not shown). 1. Open the second intake valves 7h and 7o.

A valve seat 15 on which the exhaust valve 8 is seated is formed inside an exhaust port 16 formed in the cylinder head 5, and when the exhaust valve 8 moves down and seats on the valve seat 15, the exhaust valve 15 is seated. The hole 17 is closed. A valve stem 18 slidably fitted to the exhaust valve 8 is urged upward (in a valve opening direction) by a valve spring 19, and the exhaust valve 8 is downwardly moved (in a valve closing direction) with respect to the valve stem 18 by a valve spring 20. ). Then, the valve stem 18 is driven by being pressed by an exhaust rocker arm 21 operated by a valve operating mechanism (not shown). The combustion chamber 6
A spark plug 22 is provided at the center of the.

The liquid hydrogen tank 23h is connected to the intake port 10h via a main stopper 24h, a hydrogen tank 25h and a hydrogen supply pump 26h, and the liquid oxygen tank 23o is connected to a main stopper 24o, an oxygen tank 25o and an oxygen supply pump 26o.
Is connected to the intake port 10o. Hydrogen tank 2
The hydrogen stored in 5h and the oxygen stored in the oxygen tank 25o are kept at an appropriate temperature, and the hydrogen is supplied to the combustion chamber 6 by a hydrogen supply pump 26h and an oxygen supply pump 26o, respectively.
Supplied to At this time, the driving of the hydrogen supply pump 26h and the oxygen supply pump 26o, which are metering pumps, is controlled such that the supplied amounts of hydrogen and oxygen are 1 mol of oxygen to 2 mol of hydrogen. A water tank 27 is connected to the exhaust port 16.

In FIG. 1, which is a schematic diagram, the hydrogen tank 2
5h and the oxygen tank 25o are shown as being outside the engine body, but actually, as shown in FIG. 2 and FIG.
5o is formed inside the cylinder block 28.
On the inner wall surfaces of the hydrogen tank 25h and the oxygen tank 25o, a heat insulating material 29 for suppressing heat conduction is stretched.

Next, the operation of the embodiment of the present invention having the above configuration will be described with reference to FIG.

The engine E of this embodiment performs an intake stroke and a contraction / exhaust stroke for one revolution of the crankshaft 4. First, as shown in FIG. 5 (A), the crank angle with the top dead center of the piston 2 being 0 ° is 0 ° to 180 °.
In the intake stroke corresponding to the range, hydrogen and oxygen are supplied into the cylinder 1 from the opened first intake valve 7h and the second intake valve 7o, respectively. At this time, as described above, the ratio of hydrogen and oxygen is 1 mol of oxygen to 2 mol of hydrogen, and the pressure of the mixture is atmospheric pressure.

Subsequently, as shown in FIG. 5B, the mixture of hydrogen and oxygen in the cylinder 1 is ignited by the spark plug 22 near the crank angle of 180 °. At this time, the first intake valve 7h and the second intake valve 7o are closed, and the exhaust valve 8 is also closed with the valve stem 18 at the lowered position shown by the solid line in FIG.

When a mixture of hydrogen and oxygen is burned in the cylinder 1, a reaction of 2H ₂ (2 mol) + O ₂ (1 mol) → 2H ₂ O (2 mol) occurs, and 2 mol of hydrogen and 1 mol of The mixture of oxygen changes to 2 moles of water vapor. As a result, the volume of water vapor generated with respect to the volume of the original air-fuel mixture is reduced to 2/3, so that the pressure in the cylinder 1 is also reduced to 2/3 and 2/3.
Atmospheric pressure.

In this way, when steam of 1/3 atm is generated by combustion of the mixture of 1 atm, the first intake valve 7h, the second intake valve 7o, and the exhaust valve 8 are closed, and Since the inside of the crankcase facing the back of the piston 2 communicates with the atmosphere and is at atmospheric pressure, FIG.
(C) As shown in FIG.
In the contraction stroke corresponding to the range, the negative pressure (negative pressure based on the atmospheric pressure) inside the cylinder 1, that is, the atmospheric pressure acting on the back surface of the piston 2 and the negative pressure acting on the top surface of the piston 2 , The piston 2 is driven toward the top dead center.

A hydrogen tank 25h and an oxygen tank 25o are formed in the cylinder block 28 so as to surround the cylinder 1, and low-temperature hydrogen and oxygen obtained by vaporizing liquid hydrogen and liquid oxygen are present in the inside thereof. Without providing a water jacket and cooling fins, the engine E whose temperature has increased due to the combustion of the air-fuel mixture and the steam generated by the combustion of the air-fuel mixture can be effectively cooled with the low-temperature hydrogen and oxygen. In particular, by cooling the steam generated by the combustion of the air-fuel mixture to promote liquefaction, the negative pressure generated in the cylinder 1 is increased to increase the engine E
Output can be improved.

If the cooling by hydrogen and oxygen becomes excessive, the steam generated by combustion of the air-fuel mixture may freeze in the cylinder 1 and hinder the sliding of the piston 2, but the hydrogen tank 25h and the oxygen tank Heat insulation material 2 inside of 25o
By covering with 9, the excessive cooling can be prevented and freezing of water vapor can be avoided.

When the crank angle reaches 240 °, the pressure inside the cylinder 1 becomes 1 atm. When the crankshaft 4 further rotates due to inertia and the crank angle exceeds 240 °,
The pressure inside the cylinder 1 becomes 1 atmosphere or more. Therefore,
As shown in FIG. 5 (D), the crank angle is 240 ° to 36 °.
By opening the exhaust valve 8 in the exhaust stroke corresponding to the range of 0 °, the steam in the cylinder 1 can be exhausted to the exhaust port 16. Water vapor is exhaust port 16
Is released to the atmosphere, but water generated by condensation of water vapor is stored in a water tank 27.

When the exhaust valve 8 is opened, the exhaust rocker arm 21 moves up to the dashed line position and the valve stem 18 moves up to the dashed line position by the elastic force of the spring 19, so that the exhaust valve 8 is opened. It becomes possible to separate from the valve seat 15 against the spring 20. Therefore, when the internal pressure of the cylinder 1 becomes 1 atmospheric pressure or more, the exhaust valve 8 is automatically separated from the valve seat 15 by a pressure difference from the atmospheric pressure.

By the way, the pressure inside the cylinder 1 becomes 1 due to the variation of the mixture ratio of hydrogen and oxygen in the mixture.
Since the timing when the pressure becomes equal to or higher than the atmospheric pressure may fluctuate, the opening timing of the exhaust valve 8 (the valve stem 18
It is desirable that the crank pressure be set slightly earlier than the position where the crank angle is 240 ° to prevent the internal pressure of the cylinder 1 from exceeding 1 atm. Even if the exhaust valve 8 can be opened by moving the valve stem 18 upward to the chain line position in FIG. 2, if the internal pressure of the cylinder 1 is less than 1 atm, the exhaust valve 8 is closed by the action of the spring 20. Therefore, the negative pressure in the cylinder 1 can be effectively used.

While the crankshaft 4 makes one rotation, the piston 2 is driven only in the range of the crank angle of 180 ° to 240 ° (contraction stroke) as described above.
In other ranges (the crank angle is in the range of 0 ° to 180 ° and the range of 240 ° to 360 °), it is necessary to continue the rotation of the crankshaft 4 due to inertia of a flywheel or the like. May be hindered. Therefore, in the present embodiment, the engine E is an in-line 6 cylinder or a V-type 6 cylinder, and the six cylinders 1
Are shifted by 60 °.

That is, in the state shown in FIG. 6, the crank angle of the # 1 cylinder 1 is 0 °, the crank angle of the # 2 cylinder 1 is 60 °, the crank angle of the # 3 cylinder 1 is 120 °, # 4
The crank angle of the cylinder 1 is 180 °, the crank angle of the # 5 cylinder 1 is 240 °, and the crank angle of the # 6 cylinder 1 is 300 °, which is in a state immediately before the # 4 cylinder 1 enters the contraction stroke. Therefore, the # 4 cylinder 1 generates a driving force from the state of FIG. 6 until the crankshaft 4 rotates 60 °, and thereafter, every time the crankshaft 4 rotates 60 °, # 5 → # 6 → # 1 → # 2 The driving force is generated by each of the cylinders 1 in the order of # 3 → # 4, so that torque fluctuation of the crankshaft 4 can be minimized and smooth rotation can be achieved.

As described above, since a mixture of hydrogen and oxygen is used as fuel, the products produced by combustion of the mixture may be steam or water alone, and harmful CO and NOx may be generated. Therefore, environmental pollution due to exhaust gas can be avoided. Further, by using a mixture having a mixture ratio of 1 mol of oxygen to 2 mol of hydrogen, hydrogen or oxygen contained in the mixture is combined without remaining, and steam after combustion with respect to the volume of the mixture before combustion is used. Can be minimized.
Thereby, the driving force can be increased by generating the negative pressure after combustion to the maximum.

Although the embodiments of the present invention have been described in detail, various design changes can be made in the present invention without departing from the gist thereof.

For example, in the embodiment, a mixture of hydrogen and oxygen is used, but a mixture of hydrogen and air can be used.

[0033]

As described above, according to the first aspect of the present invention, a negative pressure is generated in the cylinder due to a reduction in volume when a mixture of hydrogen and oxygen is burned to generate steam. The crankshaft can be driven by operating the piston with negative pressure. The only product produced by combustion of the air-fuel mixture is water vapor or water.
Since x does not occur, there is no risk of polluting the environment.

According to the second aspect of the present invention,
Since the air-fuel mixture has a mixing ratio of 1 mole of oxygen to 2 moles of hydrogen, the air-fuel mixture is combined without remaining hydrogen or oxygen at the time of combustion, and the negative pressure after the combustion is generated to the maximum, thereby driving force Can be increased.

According to the third aspect of the present invention,
Since six cylinders are operated continuously at every crank angle of 60 °, any one of the cylinders always generates a driving force during one rotation of the crankshaft, thereby preventing torque fluctuation of the crankshaft. And smooth rotation can be made possible.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an engine.

FIG. 2 is an enlarged view of a cylinder head portion of the engine.

FIG. 3 is a view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is an explanatory diagram of an engine stroke.

FIG. 6 is a diagram for explaining the operating states of six cylinders.

[Explanation of symbols]

 1 Cylinder 2 Piston 3 Connecting rod 4 Crankshaft

Claims (3)

[Claims] A piston (2) slidably fitted to a cylinder (1) is connected to a crankshaft (4) via a connecting rod (3), and a mixture of hydrogen and oxygen is supplied to the cylinder (1). A negative pressure engine that rotates a crankshaft (4) by driving a piston (2) with a negative pressure generated by burning inside a cylinder, wherein a top dead center is generated while the crankshaft (4) makes one revolution. And a piston (2) moving toward the bottom dead center to draw an air-fuel mixture of hydrogen and oxygen into the cylinder (1), and an air-fuel mixture ignited near the bottom dead center burns to produce steam. The piston (2) is driven toward the top dead center by the negative pressure generated by the volume decrease when the water is generated, and the shrinkage / exhaust stroke for discharging the water vapor to the outside of the cylinder (1) from before the top dead center. , Sequentially A negative pressure engine. 2. The mixture of oxygen and oxygen is mixed with 2 moles of hydrogen.
The negative pressure engine according to claim 1, wherein the engine has a molar mixing ratio. 3. Negative pressure engine according to claim 1, characterized in that it comprises six cylinders (6) operating continuously at every 60 ° crank angle.