JPH0424135Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> The present invention relates to a gas fuel supply device for a gas engine, and is intended to reduce fluctuations in the amount of gas fuel supplied in a gas fuel/air mixer to increase the rotational speed of the gas engine. To provide a gas fuel pressure regulator capable of stabilizing the pressure regulator, increasing the response sensitivity of the gas fuel pressure regulator, and shortening the settling time.

<Prior Art> The basic structure of the gas fuel supply system for a gas engine, which is the subject of the present invention, is as shown in FIG. 1 or FIG. This type is connected to the gas fuel/air mixer 1 via a supply path 2.

In this type of prior art, as shown in FIG. 4, a gas fuel pressure regulator 3 is simply connected to a bench lily 100 of a gas fuel/air mixer 1 via a gas fuel supply path 2.

<Problems to be solved by the invention> Specifically, the gas fuel pressure regulator 3 is, for example, a diaphragm cylinder, and the valve body 23 is connected to the valve outlet 26 by the valve closing spring 21 of the diaphragm 22.
A diaphragm chamber 24 is provided at the back of the diaphragm 22 and communicated with the atmosphere.
The valve body 23 is opened and closed by the differential pressure between the valve outlet 26 and the valve outlet 26 side (that is, by essentially balancing the spring force with the negative pressure at the valve outlet side).

However, in a single cylinder gas engine, a large intake pulsating pressure affects the gas fuel/air mixer 1, so the gas fuel pressure regulator 3 communicates with the gas fuel/air mixer 1 via the gas fuel supply path 2.
The pressure on the valve outlet 26 side fluctuates accordingly.

As a result, the valve body 23 of the diaphragm 22 repeats opening and closing, disrupting the amount of gas fuel supplied to the gas fuel/air mixer 1, and increasing fluctuations in the rotational speed of the gas engine E.

The technical problem of the present invention is to stabilize the supply of gas fuel to the gas fuel/air mixer.

<Means for Solving the Problems> Means for achieving the above-mentioned problems will be described below using drawings corresponding to embodiments.

That is, the present invention provides a gas fuel supply device for a gas engine having the basic structure described above, in which a pulsating pressure buffering check valve 5 is interposed in the pressure-regulated gas fuel supply path 2, and the pulsating pressure buffering check valve 5 is The valve opens to allow fuel gas to flow under the pressure of the valley side of the intake pulsating pressure of the engine E, which is lower than the pressure in the gas fuel communication chamber 25 of the gas fuel pressure regulator 3. On the other hand, when the pressure on the mountain side is higher than the pressure in the gas fuel communication chamber 25, the valve closes against the pressure of the gas fuel pressure regulator 3 to stop the flow of fuel gas. It is characterized by being configured as follows.

<Operation> For example, the operation when the gas fuel pressure regulator 3 is a diaphragm cylinder will be described.

(1) (a) When the intake pulsating pressure generated inside the gas fuel/air mixer 1 reaches the pressure in the valley side, which is lower than the pressure in the gas fuel communication chamber 25 of the gas fuel pressure regulator 3, the pulsating pressure buffer When the non-return valve 5 opens, the diaphragm in the gas fuel pressure regulator 3 is pushed by the atmospheric pressure on the valve-opening working chamber side, and as a result, the valve body opens toward the valve outlet, and the gas fuel It is smoothly supplied to the fuel/air mixer 1.

(b) Conversely, when the intake pulsating pressure generated inside the gas fuel/air mixer 1 reaches the pressure at the mountain side, which is higher than the pressure in the gas fuel communication chamber 25, the check valve 5 closes, so that the gas The pressure in the fuel/air mixer 1 is blocked by the check valve 5 to prevent it from directly affecting the gas fuel pressure regulator 3, and the valve body of the gas fuel pressure regulator 3 opens and closes relative to the valve seat. will no longer be repeated.

As a result, according to (a) and (b), the gas fuel pressure regulator 3
Since the valve body is kept open, fluctuations in the amount of gas fuel supplied to the gas fuel/air mixer 1 are reduced.

(2) The check valve 5 opens only when the intake pulsating pressure of the gas fuel pressure regulator 3 is negative pressure, and since the negative pressure on the outlet side of the gas fuel pressure regulator 3 increases, The resisting spring force can be increased, and the spring constant can be set large.

<Effects of the invention> (1) Due to the action of the check valve installed in the gas fuel supply path, fluctuations in the amount of gas fuel supplied to the gas fuel/air mixer are suppressed to a small level, so that the rotational speed of the gas engine is reduced. fluctuations are reduced, and engine rotation is stabilized.

(2) Since the spring constant of the valve closing spring can be set to a large value, most of the valve closing force that resists the valve opening pressure in the gas fuel pressure regulator is accounted for by the spring force, and there is a negative force on the valve outlet side against the valve closing force. The proportion occupied by pressure becomes smaller accordingly.

As a result, the spring force is less affected by disturbance elements, the gas fuel pressure regulator operates smoothly, and the response sensitivity of the gas fuel pressure regulator increases, allowing the engine to take longer to settle. Can be shortened.

<Example> Hereinafter, an example of the present invention will be described based on the drawings.

Fig. 1 is a longitudinal front system diagram of a gas fuel supply system for a single-cylinder gas engine, and Fig. 2 is a front view of a gasket used in the gas fuel supply system, which is formed on one side of the single-cylinder gas engine E. A gas fuel/air mixer 1 is connected to the intake port.

The gas fuel/air mixer 1 is connected to a gas fuel pressure regulator 3 via a pressure-regulated gas fuel supply line 2, and the gas fuel pressure regulator 3 is connected to a primary pressure regulator via the gas fuel supply line. 6 and gas fuel source 4
are connected in turn.

The gas fuel/air mixer 1 includes a mixer main body 7
A mixing ventilation passage 8 is provided through the center of the mixing ventilation passage 8, a bench lily 10 is formed in the mixing ventilation passage 8, a chiyoke valve 11 is provided on the leeward side of the bench lily 10, and a bench lily 10 is provided on the lee side of the bench lily 10.
Throttle valves 12 are each pivotably supported on the windward side of gas engine E (that is, on the intake port side of gas engine E) so as to be openable and closable.

Also, a bench lily 10 is inserted from below the mixer main body 7.
The gas fuel inflow path 2a is vacated.

On the other hand, a valve body 14, which is formed by fastening an upper body 14a to a lower body 14b via a gasket 15, is integrally screwed to the lower end 7a of the mixer body 7. The fuel introduction path 2b is opened, and a pulsating pressure buffer check valve 5 and a gas fuel flow rate adjustment valve 16 are interposed in the middle of the gas fuel introduction path 2b.

The pulsating pressure buffering check valve 5 is composed of a valve chamber 17 formed on the lower end surface of the upper body 14a and a tongue piece 20 formed by cutting out a U-shaped groove 18 in the gasket 15. The diameter of the gas fuel introduction passage 2b formed in the lower body 14b is formed to be slightly smaller so as to be covered by the tongue piece 20.

The flow rate regulating valve 16 is screw-fitted from the lower end surface of the lower body 14b toward the gas fuel introduction path 2b, and adjusts the flow rate of the gas fuel depending on the degree of penetration into the valve seat 19 formed in the introduction path 2b. Configured to be variable.

The gas fuel introduction path 2b constitutes a part of the gas fuel supply path 2 together with the gas fuel inflow path 2a, and is connected to the gas fuel outlet 26 of the gas fuel pressure regulator 3.

On the other hand, the gas fuel pressure regulator 3 is a diaphragm cylinder in which a cylinder valve body 23 attached to a diaphragm 22 is connected to atmospheric pressure in a valve-opening working chamber 24 formed below the diaphragm 22 using a valve-closing spring. The opening of the valve seat 27 can be adjusted by opposing the spring force of the valve 21 and the negative pressure of the gas fuel communication chamber 25.

Therefore, the functions of this gas fuel supply device will be explained below.

In the single-cylinder gas engine E, pulsating intake pressure is generated in the gas fuel/air mixer 1 due to the vertical movement of the piston. When the pressure becomes negative than the pressure at 25, the pulsating pressure buffering check valve 5 formed by the tongue piece 20 opens as shown by the imaginary line in FIG.

As a result, in the gas fuel pressure regulator 3,
The negative pressure in the conduction chamber 25 increases and the pressure in the valve opening working chamber 24 overcomes the valve body 23 to open the valve, and gas fuel is supplied to the gas fuel/air mixer 1 through the gas fuel supply path 2. Ru.

(2) When the intake pulsating pressure of the mixing vent passage 8 becomes more positive than the pressure of the gas fuel communication chamber 25 of the gas fuel pressure regulator 3, the pulsating pressure buffering check valve 5 consisting of the tongue piece 20 closes to the first Close the valve as shown by the solid line in the figure.

As a result, the positive pressure on the side of the gas fuel/air mixer 1 is prevented from affecting the gas fuel communication chamber 25 of the gas fuel pressure regulator 3, and the diaphragm 22 is retracted in the direction in which the valve body 23 closes. The valve body 23 is kept open and the operation of the gas fuel pressure regulator 3 is stabilized.

FIG. 3 shows another embodiment of the present invention. In the above embodiment, the check valve 5 for buffering pulsating pressure was formed using a gasket 15, but in this embodiment, the gasket 1
5, a reed valve type valve body 50 is formed on the lower end surface of the upper body 14a of the valve body 14.
It is attached to 1 so that it can be opened and closed.

Further, the check valve 5 may be provided with a valve-opening spring or a valve-closing spring to appropriately adjust the opening/closing pressure.

[Brief explanation of the drawing]

Figures 1 to 3 show embodiments of the present invention;
The figure is a longitudinal front system diagram of a gas fuel supply system for a single-cylinder gas engine, Figure 2 is a front view of a gasket used in the same gas fuel supply system, and Figure 3 is a diagram showing the main components around the check valve showing another embodiment. FIG. 4 is a schematic diagram of a conventional gas fuel supply device. 1...Gas fuel/air mixer, 2...Pressure regulated gas fuel supply path, 3...Gas fuel pressure regulator, 5...
...Check valve for pulsating pressure buffer, E...Gas engine.

Claims (1)

[Scope of Claim for Utility Model Registration] A gas fuel supply device for a gas engine in which a gas fuel pressure regulator 3 of a gas engine E is connected to a gas fuel/air mixer 1 via a pressure-regulated gas fuel supply path 2, A pulsating pressure buffer check valve 5 is interposed in the pressure-regulated gas fuel supply path 2, and the pulsating pressure buffer check valve 5 absorbs the gas of the gas fuel pressure regulator 3 out of the intake pulsating pressure of the engine E. When the pressure at the valley side is lower than the pressure in the fuel conduction chamber 25, the valve opens to allow the flow of fuel gas, whereas when the pressure at the mountain side is higher than the pressure in the gas fuel conduction chamber 25. A gas fuel supply device for a gas engine, characterized in that when pressure is applied, the valve opens against the pressure of the gas fuel pressure regulator 3 to stop the flow of fuel gas.