JPS5910769A - Pressurizing device of gaseous fuel in gas engine - Google Patents

Abstract

PURPOSE:To improve efficiency of an engine without causing the necessity for providing any power source, by driving a blower with an exhaust turbine of the gas engine and supplying gas pressurized through the blower to a mixer. CONSTITUTION:In a device comprising a blower 3 driven by an exhaust turbine 2 and a mixer 4 of a gas engine main unit 1, the mixer 4 corresponds to a carburetor in a gasoline engine. Liquefied petroleum (LP) gas flowing into the blower 3 flows in the direction of an arrow head (a) through a gas regulator from a gas cylinder, and air flowing into he gas mixer 4 flows in the direction of an arrow head (b) through an air cleaner. Generally a gas engine generates a less output at full opening as compared with a gasoline engine, and this is caused by a reason that the gas engine generates an unstable output in a low speed range if a Venturi diameter emphasizing the output at the full opening is formed to large size, further gaseous fuel is supplied at a low pressure to the engine. Thence the LP gas is pressurized by the blower 3 and introduced to the mixer 4, and performance of the engine is improved.

Description

[Detailed description of the invention] Regarding.

As is well known, supercharging aims to increase output by increasing the amount of intake air, and is a method to achieve this goal without increasing the size of the engine. A special supercharger is attached to this, and by feeding a compressed amount of air with high specific gravity, the average effective pressure is increased, and the output is increased without changing the cylinder volume or rotation speed. Today, it is widely used in marine diesel engines, vehicle diesel engines, etc. Recently, it has also been adopted in gasoline engines for automobiles. In the case of a gasoline engine, the range of combustible mixture ratio is narrow, so when using a supercharged engine, it is necessary to simultaneously adjust the air flow rate and the fuel supply amount. Therefore, depending on the balance between the two, changes may occur in combustion, which may adversely affect engine performance. Furthermore, an increase in intake pressure due to supercharging causes an increase in the compression ratio of the engine, resulting in knocking, so either the pressure ratio of the supercharger or the compression ratio of the engine must be adjusted.

On the other hand, cass engines have the same problems as gasoline engines, and in the case of gas engines, the liquid LP gas is converted into a gas by depressurization in the high-pressure fuel tank.
Since it is supplied to the engine at a low pressure of 2 to 0.4'9/ctR, in the case of a supercharged engine, LP is supplied at a pressure higher than the supercharging air pressure.
It also includes the problem of the need to supply gas to the engine.

Therefore, the present invention aims to provide a gas fuel pressurizing device for a gas engine that pressurizes gas fuel and supplies it to the engine to increase the engine output, and also obtains a power source for pressurization from an exhaust turbine. It is something.

Hereinafter, the structure of the present invention will be explained based on embodiments shown in the accompanying drawings.

FIG. 1 is a system diagram of a first embodiment of the present invention, in which 1 is a gas engine main body, 2 is an exhaust turbine, 3 is a blower driven by the exhaust turbine, and 4 is a gas mixer, which is used in the carburetor of a gasoline engine. Equivalent to.

LP gas entering the blower 3 enters in the direction of arrow a from a gas cylinder (not shown) via a gas regulator.

Air entering the gas mixer 4 enters in the direction indicated by the arrow via an air cleaner (not shown).

In general, gas engines have lower full-throttle output than gasoline engines, but this is because if the diameter of the venturi is made larger, which focuses on full-throttle output, the engine becomes unstable at low speeds, so the output is lowered. Moreover, as described above, the pressure at which gas fuel is supplied to the engine is low. Therefore, although the first embodiment is a non-supercharged engine, LP gas is pressurized by the blower 3 and introduced into the mixer 4 to improve engine performance.

Fig. 2 shows a second embodiment, in which the same parts as in the first embodiment are designated by the same reference numerals and their explanations are omitted. In the case of the second embodiment, exhaust gas from the engine is transferred to the first stage The air is introduced into the exhaust turbine 2, which drives the exhaust turbine supercharging@5, and the resulting pressurized air is supplied to the mixer 4.

On the other hand, the exhaust gas that has passed through the first stage exhaust turbine 2 is introduced into the second stage exhaust turbine 6, and the blower 3 is driven by the exhaust turbine 6. In the case of the second embodiment, the engine performance is improved by adjusting the pressurization ratio of LP gas by the blower 3 with respect to the pressure ratio of the exhaust turbine supercharger 5.

FIG. 3 shows a third embodiment, which is used in a non-supercharged engine like the first embodiment, in which the blower 7 of the first stage is driven by the air turbine 2 of the first embodiment, and the An air turbine 8 is driven by pressurized air from a blower 7. An air turbine 8 drives a blower 3 for LP gas. In this case, the exhaust turbine 2- and the first stage blower 7 can be made of existing equipment that is mass-produced.

FIG. 4 shows a fourth embodiment, which is used in a supercharged engine like the second embodiment, in which the exhaust gas drives the first stage exhaust turbine 2, and the exhaust turbine 2 drives the exhaust turbine 2. Drive the feeder 5. The exhaust gas passing through the first-stage exhaust turbine 2 is introduced into the second-stage exhaust turbine 6, and the turbine 6 drives the first-stage blower 7. An air turbine 8 drives a blower 3 for LP gas.

In summary, the present invention is a gas fuel pressurizing device for a gas engine that pressurizes vaporized fuel gas and introduces it into a mixer using a blower driven by an exhaust turbine in the gas engine. By supplying it to the mixer, we aim to improve engine performance and
Since the pressure blower is driven by the exhaust turbine, it does not consume part of the engine output and does not require a power source.
Engine efficiency can also be improved.

[Brief explanation of drawings]

FIG. 1 is a system diagram of the first embodiment of the present invention, and FIG. 2 is a system diagram of the second embodiment of the present invention.
FIG. 3 shows a system diagram of the third embodiment, and FIG. 4 shows a system diagram of the fourth embodiment. 1... Gas engine body, 2... Exhaust turbine, 3...
・Follow Agent Patent Attorney Yoshihiko Okabe Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A gas fuel pressurizing device for a gas engine that pressurizes vaporized fuel gas and introduces it into a mixer using a blower driven by an exhaust turbine in the gas engine.