JPH0286921A - Stopping method for hydrogen fueled engine - Google Patents

Abstract

PURPOSE:To eliminate any stagnation of hydrogen gas in a route after engine stoppage by interrupting a gas flow passage in a state of maintaining the ignition operation of an engine, igniting the hydrogen gas in the route leading to the engine from this interrupted spot, in the engine and then exhausting it from the engine. CONSTITUTION:When a key switch 12 is turned to OFF to stop any operation of an engine 9, a controller 13 changes a solenoid-operated control valve 5 over to an (a) position from a (b) position, interrupting an alloy tank 1 and the engine 9 both. If so, hydrogen gas left over at the downstream side from the solenoid-operated control valve 5 is fed, under pressure, into a combustion chamber of its whole quantity without remaining behind in a regulator 6, a carburetor 7 and an intake manifold 10, etc., and it is ignited hereat and then exhausted in to the air. After the remaining hydrogen gas is exhausted out of the engine 9, ignition of a spark plug 11 is stopped by the controller 13 via an igniter 15, thus stopping work for the engine 9 is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a method for stopping a hydrogen engine.

[Prior Art] Generally, in the drive mechanism of a hydrogen engine, for example, a carburetor type hydrogen engine, a container housing a hydrogen storage alloy is connected to the engine through a pipe, and the hydrogen storage alloy is heated to generate hydrogen. After the pressure of hydrogen gas is regulated by a regulator installed in the pipe, it is sent from the carburetor through the intake manifold into the combustion chamber, where it is ignited by a spark plug to explode and start the engine.

Then, the engine is stopped by stopping the igniter, stopping the ignition of the spark plug, and stopping the heating of the hydrogen storage alloy to cut off the supply of hydrogen gas to the engine.

[Problems to be Solved by the Invention] However, when the engine is stopped, the hydrogen gas flowing into the engine through the pipe is not burned and exhausted from the engine, but instead is stored in the regulator, carburetor brake, and engine intake manifold. It will stay. Then, when the engine is started again, the hydrogen concentration at the start of ignition increases due to the accumulated hydrogen gas, causing an explosion outside the combustion chamber, or so-called flashback. If this backfire occurs continuously, it will cause the engine to stop, so there is a need for technology to prevent backfire during startup.

This invention was made to solve the above-mentioned problems, and its purpose is to exhaust the hydrogen gas accumulated in the hydrogen flow path when the engine is stopped, thereby preventing the occurrence of backfire when the engine is restarted. The objective is to provide a method for stopping the engine that can avoid this.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention operates by igniting and burning a container containing a hydrogen storage alloy and hydrogen gas released by the hydrogen storage alloy. The gas flow path that communicates with the engine is shut off while the engine's ignition operation is maintained, and the hydrogen gas in the path from this shutoff point to the engine is combusted within the engine, without stagnation in the path. Its purpose is to exhaust air from the engine and stop the engine.

[Operation] By employing the above-mentioned means, the present invention creates a gas flow path t[i[i] while maintaining the ignition operation of the engine, so that the hydrogen gas in the path from this cut-off point to the engine is diverted into the engine. By combusting the hydrogen gas and exhausting it from the same engine, hydrogen gas will not remain in the same path after the engine is stopped.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to Fig. 1.2.

In FIG. 1, a hydrogen storage alloy is housed in an alloy tank 1 serving as a housing container, and is heated by high-temperature cooling water, exhaust gas, etc. during engine cooling, and releases hydrogen gas. A filter 2 connected to the alloy tank 1 removes foreign substances such as alloy fine powder contained in the hydrogen gas, and sends the purified hydrogen gas to a pressure reducing valve 4 via a lower check valve 3. The check valve 3 prevents the flame from reaching the alloy tank 1 when a backfire occurs, and the pressure reducing valve 4 is operated by electromagnetic control to reduce the pressure of hydrogen gas to a value set based on the safety of the pipeline, etc. Send to valve 5.

The electromagnetic control valve 5 is switched to two positions, the a position and the b position, and allows the hydrogen gas sent from the pressure reducing valve 4 to flow downstream in the illustrated a position. The hydrogen gas that has passed through the electromagnetic control valve 5 is then transferred to the lower regulator 6.
The pressure is regulated to atmospheric pressure at , and then sent to the lower carburetor 7 . In the carburetor 7, hydrogen gas is mixed with air taken in through an air cleaner 8, passes through an intake manifold 10 of an engine 9, is forced into a combustion chamber, and is exploded by ignition of a spark plug 11.

Also, to explain the electrical configuration for driving the electromagnetic control valve 5, based on the manual operation of the engine key switch 12,
The controller 13 drives the starter 14 of the engine 9 according to a pre-stored program, and further ignites or stops the ignition of the spark plug 11 via the igniter 15. Further, the controller 13 outputs a signal to the electromagnetic control valve 5 to excite and demagnetize it and switch it to either position a or b, thereby communicating or cutting off the relationship between the alloy tank 1 and the engine 9. Further, the controller 13 is connected to an engine rotation sensor 16 that detects the rotation of the engine 9, and monitors the rotation of the engine 9 based on a detection signal from the rotation sensor 16.

Now, the operation of the engine stop device constructed as described above will be explained with reference to FIG.

At present, the electromagnetic control valve 5 is held at position a, and the engine 9 is driven by hydrogen gas supplied from the alloy tank 1. Then, when the key switch 12 is turned OFF in order to stop the operation of the engine 9, the controller 13 confirms this in step 31 (hereinafter simply referred to as S), and then drives the igniter 15 in S2. While maintaining the spark plug 11 in the engine 9 in the ignition operation, the electromagnetic control valve 5 is switched from the a position to the b position in S3 to shut off the alloy tank 1 and the engine 9.

Then, the hydrogen gas remaining on the downstream side from the electromagnetic control valve 5 is sucked in by the piston moving in the engine 9, and the entire amount is forced into the combustion chamber without remaining in the regulator 6, carburetor 7, intake manifold 10, etc. This is where it is burned and emitted into the atmosphere.

After the remaining hydrogen gas is exhausted from the engine 9, the controller 13 determines in S4 that the rotation of the engine 9 has stopped based on the signal from the engine rotation sensor 16, and then in S5 The ignition of the spark plug 11 is stopped, and the work of stopping the engine 9 is completed.

When stopping the engine 9 described above, the electromagnetic control valve 5
After stopping the supply of hydrogen gas from the alloy tank 1 to the engine 9 by the switching operation, the entire amount of hydrogen gas remaining in the path from the electromagnetic control valve 5 to the combustion chamber of the engine 9 is forced into the combustion chamber. Explosive exhaust. Therefore, when the engine 9 is stopped, there is no hydrogen gas remaining in the engine 9 and its drive circuit, and when the engine 9 is driven again, occurrence of backfire due to the remaining hydrogen gas is avoided.

In this embodiment, the ignition operation is terminated after the engine 9 is stopped; however, instead of this, for example, the number of ignitions for each cylinder of the engine 9 after the electromagnetic control valve 5 is closed may be set in advance. (1) After the solenoid control valve 5 is closed and the engine 9 has rotated a predetermined number of times, the ignition operation is not performed. It is also possible to adopt the method.

[Effects] As detailed above, according to the present invention, the excellent effect of preventing the occurrence of backfire when starting the engine again and ensuring a good start of the engine is exhibited.

[Brief explanation of the drawing]

FIG. 1 is a fluid system and electrical system circuit diagram showing a starting device used in the present invention, and FIG. 2 is a flow chart showing the operation of the controller. Alloy tank 1 as a storage container, electromagnetic control valve 5 as a communication cutoff point, engine 9゜Patent applicant Toyota Industries Corporation Nippon Steel Corporation

Claims (1)

[Claims] 1. A gas flow path that communicates between the storage container containing the hydrogen storage alloy and the engine, which is operated by igniting and burning the hydrogen gas released by the hydrogen storage alloy, is installed while maintaining the ignition operation of the engine. A method for stopping a hydrogen engine, in which the hydrogen gas in the path from the shutoff point to the engine is burned in the engine, and the hydrogen gas is exhausted from the engine without being retained in the path to stop the engine.