JPS6213508B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drain device for draining tar in a vaporizer.

For example, in an engine that uses liquefied gas as fuel, such as an LPG engine, the liquefied gas is first depressurized and vaporized in a vaporizer, and then supplied to the engine combustion chamber through a mixer. A considerable amount of tar accumulates within the vaporizer, particularly in its secondary chamber, and there is a strong possibility that this tar may adhere to the diaphragm of the vaporizer or enter other operating parts and impede the function of the vaporizer.

For this reason, conventionally, as shown in Japanese Utility Model Application Publication No. 50-153312, a drain device is attached to the secondary chamber of the vaporizer, and the tar in the secondary chamber is drained externally by manual operation of the drain valve. I was trying to drain it. However, this conventional drain device
If you forget to close the drain valve mentioned above and leave it open, the vaporized fuel in the secondary chamber may leak out through the drain valve during engine operation, causing a dangerous situation. It was becoming. Liquefied gas engines are especially frequently used in taxis, and in taxis, the above-mentioned drain valve is operated to remove tar after the day's work, so the drain valve must be opened and closed on a daily basis. However, it is common for people to forget to close the drain valve after draining the tar.

Further, in the above-mentioned Japanese Utility Model Application Publication No. 50-153312, a spring is provided that biases the valve body of the drain valve in the valve closing direction,
A drain device is also disclosed in which the drain valve is always closed unless an external force is applied. However, this type of drain device still has the problem that vaporized fuel will leak from the mounting portion of the container 23 unless the container 23 is completely sealed or removed after the tar is removed.

An object of the present invention is to provide a vaporizer drain device that solves the above-mentioned problems.

The vaporizer drain device of the present invention is characterized in that a drain valve and an on-off valve that opens when the engine is stopped are interposed in series with each other in the drain passage.

With the above configuration, even if the drain valve remains open, the opening/closing valve closes when the engine is started, thereby preventing fuel from leaking outside from the drain passage.

Hereinafter, implementation of the present invention will be described in detail with reference to the drawings.

FIG. 1 schematically shows an embodiment of the present invention applied to an LPG engine. The inside of the main body 2 of the vaporizer 1 is divided into a primary chamber 4 and a secondary chamber 5 by a partition wall 3.
It is defined as LPG input 6 in primary room 4
However, an LPG outlet 7 is opened in the secondary chamber 5, and the primary chamber 4 and the secondary chamber 5 are communicated with each other through a communication path 8 formed in the partition wall 3. The LPG input 6 is connected to a primary valve 10 that operates in conjunction with a primary diaphragm 9.
The opening degree (valve opening pressure) of the communication passage 8 is adjusted by the secondary valve 13 which is interlocked with the secondary diaphragm 11 and also controlled by the lock-off diaphragm 12. ) is adjusted. Since the structure and operation of such a vaporizer itself have been well known, further detailed explanation will be omitted.

The LPG inlet 6 is connected to an LPG tank 15 via an LPG inlet passage 14, and an electromagnetic on-off valve 16 as a fuel cut device is connected in the middle of the LPG inlet passage 14. This electromagnetic on-off valve 16
As will be described later, when the solenoid 16a is de-energized, it becomes closed (the state shown in Figure 1), and when the solenoid 16a is energized and energized, it becomes open, which is the so-called open-when-energized type. It is.

The LPG outlet 7 is connected to a fuel supply port 20 of a mixer 19 (its bench lily portion 19a) provided in the intake passage 18 via an LPG outlet side passage 17. A negative pressure outlet 22 opening into the intake passage 18 on the downstream side of the throttle valve 21 is connected to the lock-off diaphragm 1 via a pipe 23.
It is connected to a negative pressure chamber 24 defined by 2.

A drain pipe 25 is connected to the secondary chamber 5 in the vaporizer 1, and the secondary chamber 5 communicates with the outside (atmosphere) through a drain passage 25a formed within the drain pipe 25. This drain pipe 25
includes an electromagnetic on-off valve 26 of the type that closes when energized, which is opposite to the electromagnetic on-off valve 16 described above, and this electromagnetic on-off valve 2.
A manually operated drain valve 27 is interposed on the downstream side (atmospheric side) of 6. The drain valve 27 used in this embodiment has a rotary valve body 27a.
and an operating lever 27b that protrudes radially from the rotary valve body 27a, and is opened and closed by grasping the operating lever 27b and rotating the rotary valve body 27a.

A sensor 28 is attached to the drain valve 27 to detect its open/closed state. As shown in FIG. 2, this sensor 28 consists of a contact switch 29 fixed near the drain valve 27 and a rotary valve body 2
A support arm 30 extending radially and protruding from 7a, and a screw 31 screwed into the support arm 30.
and a coil spring 32 that prevents the screw 31 from rotating. When the drain valve 27 is completely closed as shown in FIG.
The switch 29 is closed by pressing a. Further, by threading the screw 31 forward and backward with respect to the support arm 30, the switch 29 can be turned off only when the drain valve 27 is in a completely closed state.
Fine adjustments are made so that it is closed.

Next, two electromagnetic on-off valves 16, 26 and a sensor 28
The electrical connection relationship will be explained below. An ignition switch 34 is connected to the positive terminal of the battery 33, and a first switch 35 and a pilot lamp 36 are connected in series between the ignition switch 34 and the ground terminal (negative terminal of the battery 33). A second switch 37 and a solenoid 16a of the electromagnetic on-off valve 16 are connected in series in parallel to the first switch 35 and the pilot lamp 36. Furthermore, in parallel with the second switch 37 and the solenoid 16a,
A solenoid 26a of the electromagnetic on-off valve 26 is connected. The first and second switches 35 and 37 are controlled by a sensor 28, and when the drain valve 27 is fully open or partially open (that is, not completely closed), the first switch 35 is closed and the second switch is closed. When the drain valve 27 is completely closed, the first switch 35 opens and the second switch 35 opens.
The switch is closed.

The operation of the apparatus of this embodiment having the above configuration will be explained below. First, when the engine is operated with the drain valve 27 completely closed and the ignition switch 34 turned on, the first switch 35 opens and the second
Since the switch 37 is closed, the pilot lamp 36 is turned off and the electromagnetic on-off valve 16 is open. On the other hand, since the ignition switch 34 is turned on, the electromagnetic on-off valve 26 remains closed regardless of whether the drain valve 27 is opened or closed. Therefore, LPG in the LPG tank 15 enters the primary chamber 4 through the electromagnetic on-off valve 16, the LPG inlet 6 of the vaporizer 1, and the primary valve 10. When LPG passes through the primary valve 10, the pressure is reduced to a level slightly higher than atmospheric pressure. The depressurized LPG passes through the communication path 8 from the primary chamber 4, is depressurized to approximately atmospheric pressure by the secondary valve 13, and enters the secondary chamber 5. LPG is secondary chamber 5
The fuel passes through the LPG outlet 7 and is supplied from the fuel supply port 20 of the mixer 19 to the engine combustion chamber (not shown).

As LPG is supplied as described above, tar accumulates in the secondary chamber 5 within the vaporizer 1. The tar accumulated in the secondary chamber 5 is discharged to the outside by opening the drain valve 27 with the ignition switch 34 turned OFF and the engine stopped. i.e. ignition switch 3
4 opens the electromagnetic on-off valve 26, so if you open the drain valve 27 manually,
The tar in the secondary chamber 5 is discharged to the outside.

After draining the tar, turn the ignition switch 34
When turned on, the electromagnetic on-off valve 26 closes as described above. Therefore, even if the drain valve 27 is partially open due to forgetting to close it after discharging tar, the drain passage 2
LPG will not leak outside from 5a. At the same time, if the drain valve 27 is not completely closed, the second switch 37 will open and the electromagnetic on-off valve 16 will close, and LPG will not be supplied to the vaporizer 1, so LPG leakage can be more reliably prevented. . Further, as described above, if the drain valve 27 is not completely opened, the first switch 35 closes and the pilot lamp 36 lights up to notify the driver of this fact.

Although one embodiment of the present invention has been described above,
The present invention is not limited to the above-described embodiment; for example, an alarm buzzer or the like may be used in place of the pilot lamp 36, and the electromagnetic on-off valve 26 may be provided downstream of the drain valve 27. Further, warning means such as the pilot lamp 36 (of course, the first switch 35 provided together with the warning means) and the electromagnetic on-off valve 16 may not be particularly provided.

As explained in detail above, the vaporizer drain device of the present invention automatically opens the on-off valve provided in series with the drain valve when the engine is started, even if the drain valve remains open. When the drain valve is closed, the leakage of liquefied gas from the drain valve is reliably prevented, and the safety of the liquefied gas engine is ensured by this device.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing one embodiment of the present invention, and FIG.
The figure is an elevational view showing an example of a sensor provided in a drain valve. 1...vaporizer, 25a...drain passage,
26...Solenoid on-off valve, 27...Drain valve, 2
8...Sensor, 34...Ignition switch.

Claims (1)

[Claims] 1. In a drain device in which a drain passage is provided in a vaporizer for discharging tar in a vaporizer that vaporizes liquefied petroleum gas, the drain passage is equipped with a manually operated drain valve and an on-off valve that opens when the engine is stopped. A vaporizer drain device characterized in that they are interposed in series with each other.