JPS6043161A - Gas supplying amount regulating device for general use engine - Google Patents

Abstract

PURPOSE:To effect sure control with a large operating force by a method wherein a vacuum at the downstream of a throttle valve is utilized as the control vacuum of the gas supplying amount regulating device for the engine using gas fuel. CONSTITUTION:When a push-button 70 is pushed upon starting an engine, a valve 42 is opened and the gas from a tank enters into the chamber 52 for a diaphragm 621 through an opening 11, however, the pressure of the gas is not so high as to push and press a spring 622, therefore, a small amount of gas is supplied to the engine from the minute clearance 52' of a valve seat 522 through the opening 12 and the engine is started. After starting, vacuum at the downstream of the throttle valve is introduced from the opening 13 into the chamber 61 for the diaphragm 611 and the chamber 62 for the diaphragm 621, the valve 42 is opened widely and the opening degree of the valve 53 is controlled in accordance with the vacuum to control the supply of the fuel. The force of the vacuum at the downstream of the throttle valve is strong and, therefore, the diaphragm may be operated surely and the control may be effected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel gas supply amount reading device for use in an internal combustion type general-purpose engine.

Conventional engines of this kind are often used in generators,
This type of engine uses Kallin as fuel, so
The disadvantage was that fuel costs increased.

For this reason, general-purpose engines that can use gas fuel such as propane gas instead of gasoline have recently been developed, but this type of engine reduces the pressure of the gas fuel to atmospheric pressure and Since it is necessary to supply gas fuel according to the operating condition of the engine, a gas supply adjustment device is interposed between the engine and the gas fuel supply source, for example, a gas cylinder filled with liquefied gas. .

However, conventional adjustment devices extract the negative pressure of the engine from between the air cleaner and the throttle valve, apply this negative pressure to a single diaphragm, and use the resulting variable strain movement of the diaphragm to control the adjustment valve in the gas flow path. Since it was configured to open and close, the amount of negative pressure that could be taken out was small, so in order to enable the control valve to be driven by diaphragm C, it was necessary to make the diaphragm large, and the operation of the diaphragm had to be finely adjusted. Therefore, it is difficult to sequentially adjust the gas supply amount in response to changes in negative pressure, and as a result, the fuel gas supply amount may be insufficient, or - it is difficult to control the concentration of carbon oxide. There was a disadvantage.

The present invention aims to provide a fuel gas supply profile θMm device that can eliminate such disadvantages.

The apparatus of the present invention will be explained below with reference to the accompanying drawings. FIG. 1 shows a power generation engine 20 to which the adjusting apparatus 10 of the present invention is attached. is connected to the gas inlet of the engine 20, and the other supply side is connected to the gas inlet of the engine 20.

The device IO of the present invention includes a receiving pipe line 11 connected to a storage pump 30 and a supply pipe system 1 connected to a waste inlet of an engine 20.
2 and a pressure detection pipe system 13 for detecting the negative pressure on the side of the engine 20, and each of the pipe threads 11, 12, and 13 is constituted by a rigid pipe or a flexible hose.

Upper i port W @ l”rtl between adjustment device 10 and storage pump 30
In many cases, a gas meter or safety device is separately added to the tank, so the receiving pipe 11 does not necessarily need to be directly connected to the storage pump 30.

The supply pipe 12 of the device 10 of the present invention can be communicated with a desired position of the receiving section 21 of the engine 20, which is provided between the combustion chamber and the air cleaner. It is desirable to establish communication between the intake part 21 of the engine and the throttle valve 23, so that the air can be mixed with the supplied atmosphere on the front side of the valve body 23' of the throat I/le valve 23. The mixing effect is good.

On the other hand, the pressure detection pipe system 13 is connected to the engine 20 side so as to extract negative pressure between the cylinder of the engine body, that is, the combustion chamber and the valve body 23' of the throttle valve. Recipient department name 1
A through hole is provided that opens into the engine, and the negative pressure generated on the engine side is taken out through this through hole.

In the embodiment, a gasoline fuel supply nozzle 25 is provided between the throttle valve 23 and the choke valve 24, and the gasoline in the float chamber 26 is drawn into the receiving section 21 from the nozzle 25. It is.

Therefore, the engine shown in this embodiment can selectively use gasoline or gas.

As shown in FIG.
0, a regulating valve s50 on the gas supply side connected to the supply pipe system 12, and a negative pressure operating mechanism 60 connected to the pressure detection pipe 13.

The on-off valve mechanism 40 includes an inlet passage 41 communicating with the receiving pipe system 11, an on-off valve 42 provided in the middle of the inlet passage 41, and a valve stem 43 of the on-off valve 42. The inflow passage 41 is formed such that a portion on the supply side of the on-off valve 42 extends at right angles to a portion on the receiving side of the on-off valve 42 .

The regulating valve mechanism 50 has a supply passage 51 that communicates with the supply pipe system 12 and also communicates with the inflow passage 41 above, and a regulating valve 52 is provided at the intermediate base of the supply passage 51. The gaseous fuel discharged from the regulating valve 52 is reduced in pressure to approximately atmospheric pressure and drawn into the engine by negative pressure.

The upper ie regulating valve 52 is provided with a valve stem 53, and in the embodiment, the tip of the valve stem 53 is made into the regulating valve 52.

The negative pressure operating mechanism 60 communicates with the pressure detection pipe system 13 and includes a first pressure chamber 61 located opposite the on-off valve 42 and a second pressure chamber 62 located opposite the adjustment valve 52. The valve stems 4 of each of the above valves are in the pressure chambers 61 and 62.
3 and 53, and the first one extended perpendicularly to each other. Second diaphragm 611. ．． 621 is provided, thereby forming one wall surface of each pressure chamber 61, 62.

The diaphragms 611.621 of the first and second pressure chambers 61.62 of the upper WG are provided with return means for constantly pressing each diaphragm 611.621 from the inside of the chamber to maintain the volume of each pressure chamber 61.62 at a maximum of 6ζ, for example. 1st. Second coil springs 612, 622 are attached, and valve rods 43, 53 facing each diaphragm are separately fixed at the center of each diaphragm 611, 621.

The first diaphragm 611 is set by a coil spring 612 to keep the on-off valve 428 closed at all times, and moves in the direction of opening the on-off valve 42 against the coil spring 612 when negative pressure is applied. It is composed of
Therefore, when the volume of the pressure chamber 61 is reduced, the opening/closing valve 42 gradually moves in the valve opening direction as the pressure chamber 61 decreases in volume.

For this reason, the opening/closing valve 42 has an O-ring 421 to ensure a sealing gap when the valve is closed, and the end of the valve stem 43 to an enlarged stage in order to prevent changes in the valve opening view only at the time of startup. The portion 422 is molded.

On the other hand, the second pressure chamber 62 has its diaphragm 6
21 to the supply path 51 side, this diaphragm 62
11, so that the second pressure chamber 62 is divided into the supply path 51 (!), and when the diaphragm 621 is in a steady state, the control valve 52 is configured to divide the second pressure chamber 62 into the supply path 51 (!).
It was added to allow for a small opening.

For this purpose, a slit 52' is formed at the base of the regulating valve 52, thereby ensuring gas flow.

Therefore, the regulating valve 52 closes the supply path 51 as the second pressure chamber 62 reduces its volume.
In the embodiment, the regulating valve 52 sequentially increases the light i/(# side expands 4
It is composed of a number of step portions 521, and is set so that the valve opening area decreases as the volume of the second pressure chamber 62 decreases.

The regulating valve 52 may be provided with a tapered portion that expands in the first order instead of providing the stepped portion 521 as in the embodiment, and in this way, the amount of gas flowing can be adjusted steplessly.

In the above, the step part 521 of the regulating valve 52 moves upward in the figure as the negative pressure increases and becomes closed, so the valve body itself can operate as a stop valve, but the on-off valve 42 Since the valve opens at , it is desirable to set the maximum valve opening position.

For this reason, in this embodiment, a regulating means for stopping the deformation movement of the diaphragm 611 at a predetermined position l, such as a cylindrical stopper 613, is provided in the upper pressure chamber 1 pressure chamber 61, thereby controlling the movement of the diaphragm 611 and thus It is configured to restrict the maximum opening position of the on-off valve 42.

Furthermore, the opening/closing valve 42 is automatically opened by the negative pressure at the time of engine starting, and in particular, the first diaphragm 611
Although it is not necessary to operate it, as in the embodiment, the diaphragm 611 is provided with a starting means such as the push button part 70, so that the first diaphragm 611 is suppressed and deformed from the outside during the starting process, thereby artificially It is desirable to configure it so that the flow path is open.

In the figure, 423 and 522 are valve seats, respectively.

The device of the present invention is as described above, and in use, the starting means, that is, the push button part 70 of the embodiment is operated to partially open the on-off valve 42, thereby causing a small amount of Gas is supplied to the engine 20 to start ignition.

When the engine 20 starts, a large negative pressure is generated because the opening degree of the throttle valve 23 is small at this point, and the first diaphragm 611 and the second diaphragm 621 are largely deformed and moved by this negative pressure, and the on-off valve 42 is fully opened. At the same time, the regulating valve 52 is moved in the valve closing direction.

Therefore, the amount of gas supplied to the engine 20 is
The maximum amount is guaranteed by fully opening the valve, and the amount is regulated to a smaller amount than by the regulating valve 524.

The rotation speed of the engine 20 increases, and the throttle valve 23
As the degree of opening increases, the negative pressure decreases, and accordingly, the 'aAM valve 52 moves in the direction of opening, thereby increasing the amount of gas supplied to the engine 20.

When the rotational speed of the engine 20 further increases and the opening degree of the throttle valve 23 reaches its maximum, the negative pressure further decreases, so the regulating valve 52 becomes the maximum opening state, the amount of gas supplied becomes maximum, and the rotational speed of the engine 20 increases. When the pressure decreases, the negative pressure increases accordingly, so the regulating valve 52 moves in the closing direction and reduces the gas supply amount.

Since the device of the present invention is configured to extract the negative pressure of the engine from the throttle valve 23 to the combustion chamber side,
In addition to being able to utilize large negative pressure, the structure uses two diaphragms, one of which opens and closes the flow path, and the other that adjusts the gas supply amount, so the amount of gas fuel supplied can be reduced. This has the effect that it can be adjusted well according to the condition of the engine.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a general-purpose engine using the device of the present invention;
FIG. 2 is a schematic side view of essential parts showing the state of connection between the device and the engine, and FIG. 3 is a longitudinal sectional side view of the device of the present invention. In the figure, 10 is the device of the present invention, 11 is a receiving pipe system, 12 is a supply pipe system, 13 is a pressure measuring pipe system, 20 is an engine, 21 is a receiving part,
40 is an on-off valve mechanism, 41 is an inflow path, 42 is an on-off valve, 43
50 is a valve stem, 50 is a regulating valve mechanism, 51 is a supply path, 52 is a regulating valve, 53 is a valve stem, 60 is a negative pressure operating machine #, 61 is a first pressure chamber, 611 is a first diaphragm, 62 is a second pressure chamber, 6
21 indicates a second diaphragm. Patent author Tokyo Rika Kogyo Co., Ltd. Agent Seiji Matsuda -38'/

Claims (1)

[Scope of Claims] 1. A pressure-detecting pipe that extracts the negative pressure of the engine from a side of the engine throttle valve to the combustion chamber, a supply pipe system that supplies fuel gas to a receiving section of the engine, and fuel that supplies the engine to the engine. a receiving pipe system for receiving gas from a gas supply source (a gas supply source), a negative pressure operating mechanism connected to the pressure detection pipe line inside, a regulating valve mechanism connected to the supply pipe system above, and the above-mentioned It has an on-off valve mechanism connected to the receiving pipe system,
The negative pressure operating mechanism includes a first tube connected to the pressure detection pipe system. A second pressure chamber is provided, and a diaphragm is installed in each of these pressure chambers so as to form a wall surface of each pressure chamber, and the first pressure chamber is provided with a diaphragm. The second pressure chamber is provided with a return means for maintaining each diaphragm in a steady state when no negative pressure acts on the pressure chamber, and the diaphragm of the second pressure chamber is connected to the regulating valve mechanism. , a regulating valve is provided which gradually changes the opening surface of the supply passage by a deforming action of the diaphragm according to negative and positive changes, and the supply passage is configured to communicate with the upper H pipe thread; An on-off valve is connected to the diaphragm of the first pressure chamber and opens the inflow passage communicating with the supply passage by the firing operation caused by the negative pressure of the diaphragm, and the regulating valve is operated to prevent the increase of the negative pressure. A gas supply amount adjustment device for a general-purpose engine is characterized in that it is configured to operate in a direction that accordingly reduces the opening area of the upper Me supply path. 2. The pressure detection pipe system is connected to the insulator located at the receiving part between the carburetor and the cleaner on the upper side, and this insulator is provided with a through hole that opens into the receiving part as a connection part for the pressure detection pipe thread. A gas supply amount adjusting device for a general-purpose engine according to claim 1, characterized in that: 3. The gas supply amount adjusting device for a general-purpose engine according to claim 1, wherein the supply pipe system is connected to the receiving section between the throttle valve and the cleaner.