JPH05240113A - Check valve - Google Patents

Abstract

PURPOSE:To obviate conventional spring and prolng the operation life and reduce the cost by operating magnetic replusion between a sticklike member and ringlike members at an outer pipe portion into whose inside the stick member is inserted, conducting energization by this so that a valve body may be closed at all times. CONSTITUTION:This check valve 20F is interveniently furnished at a passage which supplies fuel to the sub chamber of a sub chamber type thin combustion gas engine. In this instance, a sticklike member 10 is inserted into the inside of the outer pipe portion 24 of the check valve 20F, and a valve body 13 is provided at one end portion of the sticklike member 10. Meanwhile, a valve seat 12 is formed at one end portion of the outer pipe portion 24 which is on a side to come into contact with the valve body 13, and a ringlike member 28 consisting of a magnet having the quality of high temperature durability is provided at the other end portion of the sticklike member 10. In addition, a similar ringlike member 26 is provided at the other end portion of the outer pipe portion 24. Respective magnetic fields are arranged so that both ringlike members 26, 28 may repel each other. As a result, by operating required force U to the sticklike member 10, and by this, the valve body 13 is seated at the valve seat 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve provided in a passage for supplying a fuel gas to a sub chamber of a lean chamber combustion gas engine.

[0002]

2. Description of the Related Art A sub-chamber lean combustion gas engine 1 shown in FIG. 3 includes a piston 2 and a cylinder 3, and a sub-chamber 4 is formed above the cylinder 3. A spark plug 5 is provided in the sub chamber 4, and a passage 6 for supplying a fuel gas is in communication therewith. A check valve 8 for preventing backflow is provided in the passage 6.

As the check valve, a ball type, a plate type,
There are poppet type and others, but there are advantages and disadvantages in sealing performance, durability, price, etc. And conventionally, the poppet type check valve shown in FIG. 4 was considered to be most suitable. In particular, in the sub-chamber 4 (FIG. 3), the air and the fuel gas are mixed by a numerical value near the theoretical air ratio, and the fuel gas burns in a state in which the fuel gas concentration is higher than that in the cylinder of the lean burn gas engine. Is likely to occur. Then, the check valve may be closed or left open due to the adhesion of the carbon. In order to prevent such a situation, it is said that a poppet type check valve having high resistance to carbon is suitable.

In FIG. 4, a poppet type check valve, generally designated by reference numeral 8, includes an outer cylinder portion 9 and a rod member 10.
A gas introduction hole 11 and a valve seat 12 are formed in the outer cylinder portion 9, and a valve body 13 is formed at one end of the rod member 10. A spring 14 is interposed between the outer cylindrical portion 9 and the rod-shaped member 10, and one end of the spring is supported by a spring retainer 15 formed on the rod-shaped member 10.

When the differential pressure between the upstream side and the downstream side of the check valve 8 becomes equal to or more than the set value, the valve is opened, and the valve body 13 moves downward in FIG. 4 and is separated from the valve seat 12. Then, the fuel gas introduced from the gas introduction hole 11 is ejected. On the other hand, since the repulsive force of the spring 14 acts in the extending direction, the rod member 10 is always biased upward in FIG. 4, and the check valve 8 is normally closed.

[0006]

However, due to the high concentration of the fuel gas, the inside of the sub chamber 4 burns at a high temperature. Then, the spring 14 of the poppet type check valve 8
Is very small and therefore lacks durability at high temperatures and is damaged by the high temperatures. As a result, the rod-shaped member 10 is no longer biased upward in FIG.
There is a problem that the check valve 8 remains open.

It is also conceivable to form the spring 14 from a material having excellent heat resistance. However, it is very difficult to manufacture a very fine spring using a heat-resistant material, such as a poppet-type check valve used in the fuel gas supply passage 6 to the sub chamber 4, The cost will increase.

The present invention has been proposed in view of the above-mentioned problems of the prior art, and is a check valve provided in a passage for supplying fuel gas to a sub chamber of a lean burn gas engine.
The purpose is to provide a check valve with excellent durability against carbon and high heat.

[0009]

A check valve of the present invention is a check valve which is provided in a passage for supplying a fuel gas to a sub chamber of a lean combustion gas engine of a sub chamber type and has a cylindrical shape. An outer tubular portion, and a rod-shaped member inserted inside the outer tubular portion,
A valve body provided at one end of the rod-shaped member, a valve seat formed at the end of the outer cylinder portion on the side in contact with the valve body, and formed at the end of the rod-shaped portion opposite to the valve body. A ring-shaped member made of a high-temperature durable magnet and a ring-shaped member made of a high-temperature durable magnet formed on a portion of the outer cylinder opposite to the valve seat. The magnetic poles of the strip-shaped members are arranged so as to repel each other.

In practicing the present invention, a nickel alloy type magnet is preferable as the high temperature durable magnet. However, there is no intention to add a limiting condition to the type of magnet as long as it can withstand the high temperature in the combustion of the sub chamber of the sub chamber lean gas combustion engine.

The repulsive force between the ring-shaped members is preferably set so that the valve is opened when the differential pressure between the upstream side and the downstream side of the check valve becomes equal to or more than a set value.

[0012]

According to the check valve of the present invention having the above-mentioned structure, the rod-shaped member and the ring-shaped member of the outer cylinder repel each other. It is always urged to sit on a seat. As a result, unlike a conventional poppet type check valve, a spring is not required, so a check valve installed in a passage supplying fuel gas to a sub chamber of a lean chamber gas engine with high heat is added. However, there is less concern about damage due to high heat, and the frequency of replacement work due to this is significantly reduced.

In addition to this, since it operates as a normally closed check valve due to the magnetic repulsive force of the rod-shaped member and the ring-shaped member of the outer cylinder portion, it is similar to the conventional poppet type check valve or more than that to carbon. It has excellent durability.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2, the same members as those in FIG. 4 are represented by the same reference numerals.

The check valve of the present invention, which is generally designated by the numeral 20 in FIG. 2, has a structure substantially similar to that of the conventional poppet type check valve 8 shown in FIG. That is, the outer cylinder part 24 and the rod-shaped member 10 are included, the gas introduction hole 11 and the valve seat 12 are formed in the outer cylinder part 24, and the valve body 13 is formed at one end of the rod-shaped member 10. ing.

However, unlike the check valve of FIG. 4, no spring is interposed between the outer cylinder portion 24 and the rod member 10. Instead, a first ring-shaped member 26 is provided on the opposite side (upper side in FIG. 2) of the outer cylindrical portion 24 to the valve seat, and on the opposite side (upper side in FIG. 2) from the valve body of the rod-shaped member 10. A second ring-shaped member 28 is provided near the end 22.

The first and second ring-shaped members 26, 2
Reference numeral 8 is composed of a nickel-based magnet, and N poles face each other as shown in FIG. 1, or S poles face each other as shown by brackets in FIG. With such an arrangement, the ring-shaped member 2
A magnetic repulsive force acts between 6 and 28, and a force as indicated by an arrow U in FIG. 1 acts on the rod member 10 via the second ring member 28 and the step portion 24 engaged with the second ring member 28. To do. As a result, the force indicated by the arrow U in FIG. 2 also acts on the valve body 13, and the valve body 13 is seated on the valve seat 12 to close the valve.

Here, the magnetic repulsive force between the ring-shaped members 26 and 28 is set to be equal to the sum of the self-weight of the rod-shaped member 10 and the pressure toward the valve downstream side at the set pressure difference, which is the check valve. The valve is set to open when the pressure difference between the upstream side and the downstream side exceeds a set value. Note that, when the valve is opened, it operates in substantially the same manner as the conventional poppet-type check valve, and therefore a duplicate description is omitted.

[0019]

As described above, according to the check valve of the present invention, the valve is normally closed due to the magnetic repulsive force between the rod-shaped member and the ring-shaped member of the outer cylinder. As a result, unlike the conventional poppet-type check valve, a spring is not required, the risk of damage due to high heat is reduced, and the frequency of replacement work is significantly reduced. As a result, usually 1000
The durability of the conventional poppet type check valve, which had an operating life of only about an hour, has dramatically increased.

In addition to this, since it is normally biased, it has excellent durability against carbon.

Further, since the spring portion, which is the most expensive in the conventional poppet type check valve, can be omitted, the price of the check valve becomes extremely low.

[Brief description of drawings]

FIG. 1 is an enlarged partial sectional view showing an essential part of the present invention.

FIG. 2 is a sectional front view showing an embodiment of the present invention.

FIG. 3 is a cross-sectional front view showing a sub-chamber lean-burn gas engine to which the present invention is applied.

FIG. 4 is a sectional front view showing a conventional poppet type check valve.

[Explanation of symbols]

 1 ... Sub-chamber lean combustion gas engine 2 ... Piston 3 ... Cylinder 4 ... Sub-chamber 5 ... Spark plug 6 ... Fuel gas supply passage 8, 20 ... Reverse Stop valve 9, 24 ... Outer cylinder part 10 ... Rod member 11 ... Gas introduction hole 12 ... Valve seat 13 ... Valve body 14 ... Spring 15 ... Spring retainer 22 ... -End of rod-shaped member opposite to valve body 26 ... First ring-shaped member 28 ... Second ring-shaped member

Claims (1)

[Claims] 1. A check valve provided in a passage for supplying a fuel gas to a sub-chamber of a sub-chamber lean combustion gas engine, wherein a cylindrical outer cylinder portion and an inside of the outer cylinder portion are provided. The rod-shaped member to be inserted, the valve body provided at one end of the rod-shaped member, the valve seat formed at the end of the outer tubular portion on the side in contact with the valve body, and the valve body of the rod-shaped portion A rod-shaped member including a ring-shaped member made of a high-temperature durable magnet formed at the end on the opposite side, and a ring-shaped member made of a high-temperature durable magnet formed on a portion of the outer cylinder portion opposite to the valve seat. The check valve is characterized in that the magnetic poles of the member and the ring-shaped member of the outer cylinder are arranged so as to repel each other.