JPH021470Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention belongs to the technical field of fuel supply devices for gas engines. For example, as shown in FIG. A slow outlet 41 is provided, a main inlet 22 is provided on the windward side of the throttle valve 50 of the mixer 17 fixed to the engine main body 6, a slow inlet 23 is provided on the leeward side of the mixer 17, and the main outlet 40
and the main inlet 22 through the main pipe 24, and the slow outlet 41 and the slow inlet 23 through the slow pipe 25.
The present invention relates to a fuel supply system for a gas engine, in which a main outlet 40 and a slow outlet 41 are provided with flow rate adjusting means 42 and 42', respectively.

In this device, if the main outlet 40 and the slow outlet 41 of the pressure regulator 21 are provided close to each other, there is a problem that the engine will stop due to a decrease in the concentration of the air-fuel mixture for the following reason. .

That is, when the engine is operating with no load or light load, the throttle valve 50 closes and the throttle valve 50 closes.
The negative pressure on the leeward side becomes high, while the negative pressure on the leeward side becomes low, and the differential pressure between them becomes large. Therefore, due to the pressure difference, air on the windward side enters the main pipe 24 from the main inlet 22, and the main outlet 4
0 to the slow outlet 41 and dilutes the fuel gas supplied to the mixer 17 from the slow inlet 25. If this happens, the mixture becomes too lean and the engine stalls.

In order to solve this problem, by separating the main outlet 40 and slow outlet 41 from each other as far as possible, the buffer space created by the pressure regulating chamber 30 in the mixer 17 located between both outlets 40 and 41 can be increased. Take the main exit 40 to the slow exit 41
It is necessary to prevent air from being drawn in due to short circuits.

Conventionally, as a specific means for this purpose, the seventh
As shown in the figure, the main outlet 40 and the slow outlet 4
1 is the case body 2 of the fuel gas pressure regulator 21
Since they were disposed far apart in the circumferential direction on the peripheral wall of No. 6, the following drawbacks occurred.

That is, the gas engine 1 and the pressure regulator 21
For example, when installing compactly inside the casing of a heat pump unit, the gas flow rate adjustment section is separated into two locations, and if one location is located in a location that is easy to operate, the other location may be located in a location that is difficult to operate. You end up getting into it. For this reason, it takes time and effort to adjust the gas flow rate from outside the casing through the driver hole.
It was inefficient.

Furthermore, depending on the arrangement within the casing, it is inconvenient that the pressure regulator 21 must be removed from the casing in order to adjust the two separated components.

The present invention aims to efficiently adjust the main gas flow rate and the slow gas flow rate by arranging the main outlet and the slow outlet in close proximity to each other while preventing the air from short-circuiting. This is the purpose.

As an improved structure for this purpose, for example, as shown in FIGS. 2 and 3, gas outlets 39, 39', and fold up the starting end 47 of the gas outlet 39 on the bottom wall side to open near the center of the bottom of the pressure regulating chamber 30 inside the case body 26, and open both gas outlets 39,
The starting ends of gas outlets 39 and 39' are separated far from each other to open into the pressure regulating chamber 30, and the main outlet 40 is communicated with one of the outlet sides of both gas outlets 39 and 39', and the slow outlet 41 is communicated with the other side. Exit 40 and slow exit 4
1 are provided close to each other, and the bottom wall side gas outlet 3
9 is characterized in that the lower part of the return spring 37 of the pressure regulating mechanism 35 in the pressure regulating chamber 30 is inserted and supported within the upward starting end 47 of the pressure regulating mechanism 9.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a longitudinal side view of a water-cooled two-stroke gas engine.

This engine 1 is located above the crankcase 2.
A cylinder block 4 that slidably accommodates a piston 3 is attached, and a head block 5 is fixed above the cylinder block 4 to form an engine body 6.

A combustion chamber 7 is formed between the head block 5 and the upper part of the piston 3, and an exhaust port 9, a scavenging port 10, and an intake port 11 are opened in order from the top on the inner surface 8 of the cylinder on which the piston 3 slides up and down. These openings 9, 10, and 11 are formed in a so-called piston valve type two-stroke engine that opens and closes above and below the piston 3.

The exhaust port 9 communicates with a muffler 13 through an exhaust port 12, the scavenge port 10 communicates with a crank chamber 15 in the crankcase 2 through a scavenge passage 14, and the intake port 11 communicates with an air cleaner through an intake passage 16 and a mixer 17. 18, respectively.

The mixer 17 is provided with a fuel gas supply system G that supplies fuel gas from a gas supply source 19 such as city gas or LPG. This fuel gas supply system G includes a supply pipe 20 connected to a gas supply source 19, a pressure regulator 21 that reduces the pressure of the fuel gas from the supply pipe 20 to approximately atmospheric pressure, and a mixer 1 from the pressure regulator 21.
A main pipe 24 and a slow pipe 25 connecting the main gas inlet 22 and the slow gas inlet 23 provided in 7
and a mixer 17.

As shown in FIGS. 2 and 3, the pressure regulator 21 includes a case body 26 and a case lid 27 that covers the case body 26.
A casing C is formed, and the inside of the casing C is divided by a diaphragm 28 into an atmosphere communication chamber 29 and a pressure regulation chamber 30, and the atmosphere communication chamber 29 is connected to a communication hole 31.
It is connected to the atmosphere.

A gas inlet 32 is opened in the wall of the case body 26 in the pressure regulating chamber 30, and a valve body 34 provided at an opening 33 of the gas inlet 32 on the pressure regulating chamber 30 side is opened and closed by a pressure regulating mechanism 35. It's like this.

This pressure regulating mechanism 35 includes a swinging arm 36 that swings in conjunction with the expansion and contraction of the diaphragm 28, and an operating lever 3 that is pushed in against a return spring 37 by the swinging arm 36.
8 and a valve body 34 provided at the end thereof,
Only when the internal pressure of the pressure regulating chamber 30 falls below atmospheric pressure, the diaphragm 28 contracts, and in conjunction with this, the operating lever 38 swings via the swing arm 36, and the valve body 34 opens the gas inlet 32. The main outlet 40 and the slow outlet 41 are opened to maintain the pressure regulation chamber 30 at atmospheric pressure.
The fuel gas is supplied to the mixer 17.

The gas outlets 39, 39' of the pressure regulator 21 include a main outlet 40 for running operation and a slow outlet 41 for idle motion, and the main outlet 40 is for the mixer 1.
The slow outlet 41 is connected to the main gas inlet 22 on the windward side of the throttle valve 50 of the mixer 17 through a main gas inlet 24, and the slow outlet 41 is communicated with the slow inlet 23 on the leeward side of the throttle valve 50 of the mixer 17 through a slow pipe 25. .

The main outlet 40 and the slow outlet 41 each have flow rate adjusting means 4 for adjusting the gas flow rate.
2,42' are provided. That is, the flow rate adjustment means 4
2 and 42', as shown in FIGS. 3 and 4, the passage cross-sectional area S of each gas outlet 39, 39' can be changed by adjusting the forward and backward movement of an adjusting screw 43.

FIG. 2 is a longitudinal cross-sectional side view of the pressure regulator 21, and FIG. 3 is a cross-sectional plan view.

A gas outlet 39' is opened in a peripheral wall portion of the case body 26 facing the inlet 32, and a flow rate adjusting means 42' for adjusting the gas flow rate disclosed in FIG. 4 is provided.
The throw outlet 41 is connected to the gas outlet 39'.

In the bottom wall portion 45 of the case body 26, there is provided another gas outlet 39 adjacent to the lower side of the gas outlet 39'.
open in parallel. Starting end 47 of this gas outlet 39
is folded upward to open near the center of the bottom of the pressure regulating chamber 30 inside the case body 26. As a result, the starting ends of both gas outlets 39, 39' are separated far from each other and open into the pressure regulating chamber 30.
The gas outlet 39 has a main outlet 40 equipped with a flow rate regulating means 42 shown in FIG. 4 in the same manner as described above.
Connect.

In this way, the slow outlet 41 and the main outlet 40 are vertically arranged adjacent to each other, and both flow rate adjusting means 42 and 4 provided at both outlets 41 and 40 are arranged in parallel.
2' are arranged close to each other vertically so that they can be adjusted from the same side.

In addition, the upward starting end 47 of the bottom wall side gas outlet 39
Inside, the return spring 3 of the pressure regulation mechanism 35 in the pressure regulation chamber 30
7 is inserted and supported.

As a modification of the above embodiment, as shown in FIG. 5, in plan view, the slow outlet 41 and the main outlet 40 are arranged side by side with a slight shift left and right, and both flow rate adjusting means 42, 42'
It is conceivable to place the two in close proximity to each other on the left and right so that they can be adjusted from the same top surface.

Further, as shown in FIG. 6, the gas outlet 39 on the bottom wall side may be formed by a starting end 47 recessed in the bottom wall of the case body 26 and an L-shaped pipe 51 connected to the starting end 47. In this case, it becomes possible to reduce the wall thickness of the base portion 45, which contributes to reducing the weight of the pressure regulator 21 as a whole.

Further, a main outlet 40 is connected to the gas outlet 39' on the peripheral wall side, and a slow outlet 41 is connected to the gas outlet 39' on the bottom wall side.
You may change it to connect.

Since the present invention is configured as described above, it has the following effects.

(a) By locating both gas outlets far apart from each other in the pressure regulating chamber of the pressure regulator, when the throttle valve is closed, the air on the windward side of the throttle valve enters from the main outlet to the slow outlet in a short circuit. In order to prevent this, only the fuel gas is always properly supplied from the slow outlet and the engine rotation is maintained correctly. Both of the provided flow rate adjustment means can be put together in one place and the flow rate adjustment operation can be easily performed at the same time.

As a result, when using the entire engine built into the casing of a heat pump unit, etc., both flow rate adjustment means can be easily located in easy-to-operate locations, making flow rate adjustment operations for both easy and highly accurate. Moreover, it can be done quickly and efficiently.

(b) Since both flow rate adjustment means are located in one place and the flow rate adjustment operation can be performed at the same place, the degree of freedom in layout design increases accordingly.

C. Since the lower part of the return spring is inserted here using the starting end of the gas outlet on the bottom wall side, the total length of the return spring can be increased by this insertion dimension.
Thereby, the return spring can be made highly sensitive with a small rate of change in tension with respect to the expansion/contraction operation dimension, and the supply pressure of fuel gas to the mixer can be finely adjusted with high precision.

Furthermore, since the lower part of the return spring is fitted inside and guided by the starting end of the gas outlet on the bottom wall side, the return spring can be expanded and contracted stably, and the supply pressure of fuel gas can be stabilized. .

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 shows a water-cooled 2
FIG. 2 is a vertical side view of the cycle gas engine, FIG. 2 is a vertical side view of the pressure regulator, FIG. 3 is a cross-sectional plan view of FIG. 2 with the pressure regulating mechanism 35 omitted, and FIG. 5 is a schematic plan view of the main part of another embodiment, FIG. 6 is a longitudinal sectional side view of the main part of another embodiment, and FIG. 7 is a diagram corresponding to FIG. 3 of the conventional example. It is. 1... Gas engine, 6... Engine body, 1
7... Mixer, 21... Pressure regulator, 22... Main inlet, 23... Slow inlet, 24... Main pipe, 25... Slow pipe, 26... Case body, 3
0...Pressure regulation chamber, 32...Inlet, 35...Pressure regulation mechanism, 37...Return spring, 39, 39'...Gas outlet, 40...Main exit, 41...Slow outlet,
42, 42'...adjustment means, 47...starting end, 5
0...Throttle valve.

Claims (1)

[Scope of utility model registration request] The fuel gas pressure regulator 21 of the gas engine 1 is provided with an inlet 32, a main outlet 40, and a slow outlet 41, and the main inlet 2 is provided on the windward side of the throttle valve 50 of the mixer 17 fixed to the engine body 6.
2, a slow inlet 23 is provided on the leeward side, the main outlet 40 and the main inlet 22 are communicated through the main pipe 24, the slow outlet 41 and the slow inlet 23 are communicated through the slow pipe 25, and the main outlet 40 and the slow inlet are connected through a slow pipe 25. In a fuel supply system for a gas engine configured by providing flow rate adjusting means 42, 42' at the outlet 41, the peripheral wall portion and the bottom wall portion of the case body 26 of the pressure regulator 21 are close to each other. Gas outlets 39 and 39' are provided at the respective locations, and the starting end 47 of the gas outlet 39 on the bottom wall side is folded upward to open near the center of the bottom of the pressure regulating chamber 30 inside the case body 26. The starting ends of the gas outlets 39, 39' are separated far from each other to open into the pressure regulating chamber 30, and the main outlet 40 is communicated with one of the outlet sides of both gas outlets 39, 39', and the slow outlet 41 is communicated with the other side. The main outlet 40 and the slow outlet 41 are provided close to each other, and the lower end of the return spring 37 of the pressure regulation mechanism 35 in the pressure regulation chamber 30 is located inside the upward starting end 47 of the bottom wall side gas outlet 39. A fuel supply device for a gas engine, characterized in that a fuel supply device for a gas engine is inserted and supported.