JP3883866B2 - Engines, especially reciprocating piston engines - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine having two members engaged with each other inside and outside, more preferably a reciprocating piston engine, particularly a two-cycle large diesel engine, having at least one cylinder having an exhaust hole that can be controlled by an exhaust valve. The cylinder has a cylinder head, and a seating member provided for the exhaust valve and provided with an exhaust hole is inserted into the cylinder head. In the seam region, there are provided a cooling passage through which a coolant can be supplied, a seal mechanism that is offset in an axial direction and closing each other, and a support surface that receives mutual support force. These support surfaces are provided with an engine, more preferably a reciprocating piston engine, provided with an indicator hole terminating in the outer surface to indicate leakage. Emissions, in particular, relates to a two-stroke large diesel engine.
[0002]
[Prior art]
In a known two-cycle large diesel engine of the type described above, each cylinder has an exhaust hole that is provided in the cylinder head and can be opened and closed by an attached exhaust valve. In such a two-cycle large diesel engine, a seating member that has a valve seat that cooperates with the exhaust valve and through which the exhaust hole passes is inserted in the cylinder head, and the seating member is a horizontal support surface thereof. Is supported by the support surface of the cylinder head provided correspondingly. The seating area of the seating member is cooled. For this reason, a circulating cooling passage in which cooling water can be supplied is provided in a seam region between the seating member and the cylinder head. On the upper side and the lower side of the cooling passage, there are provided seal rings that are inserted into grooves that circulate around the seating member and are configured as so-called O-rings. This seal ring is for sealing the cooling passage. However, severe temperature loads can cause situations where the lower O-ring, particularly close to the combustion chamber, is damaged, which results in loss of sealing. As a result, cooling water can enter the combustion chamber, which is highly undesirable and can lead to premature wear of the cylinder liner sliding surfaces. In this case, there is a risk that hot combustion gases may pass through the cooling passages, thereby losing the cooling effect. Such danger is particularly imminent when, for example, foreign particles such as carbon particles enter between the seating surfaces, so that the seating surfaces do not accurately contact each other.
[0003]
The indicator hole indicates such a leak, but there is a risk that the kind of damage described above has already occurred by the time it is shown as such. Even if it is disregarded, the cooling water coming out of the index hole not only leads to the loss of the cooling water, but also leads to the engine room getting wet, which is also not preferable.
[0004]
[Problems to be solved by the invention]
In view of the above circumstances, an object of the present invention is to improve a mechanism of the kind described at the beginning by simple and low-cost means so that high operational reliability is achieved.
[0005]
[Means for Solving the Problems]
According to the present invention, according to the present invention, the sealing mechanism provided for the cooling passage includes a rotating flat seal ring sandwiched between the support surfaces, and the flat seal ring includes the support surface. This is solved by the fact that a passage system that connects the side surfaces that circulate is connected to each other, and the passage system communicates with the indicator hole.
[0006]
Such a solution completely eliminates the disadvantages of the known mechanisms as described above. A flat seal ring sandwiched between the support surfaces provides high certainty to prevent leakage. At this time, the flat seal ring can be configured in a simple manner so that foreign particles such as carbon particles can be crushed thereby preventing the formation of cracks in any case. Similarly, a material having a relatively high heat resistance can be used to form a flat seal ring. This allows an increase in operating temperature, which has a positive effect on the achievable efficiency. Preferably, it is sufficient if the sealing mechanism provided on the flat seal ring has only a flat seal ring. At this time, no other sealing means is required.
[0007]
Preferred embodiments and preferred developments of the solutions described in the superordinate claims are described in the dependent claims. For example, in a two-cycle large diesel engine of the kind mentioned at the outset, a flat seal ring inserted between the support surfaces is preferably provided for the cooling mechanism sealing mechanism on the lower combustion chamber side. This seal mechanism can be configured substantially. This is because the sealing material is exposed to a higher temperature load than the upper sealing material at a distance from the sealing material. The upper sealing material may simply be configured as an O-ring.
[0008]
The fact that the flat seal ring is formed as a metal ring can be a further suitable solution. This makes it possible to embody the characteristics described above in a very simple way. Preferably, a copper alloy or a relatively soft alloy steel can be used to form a flat seal ring. In this way, it can be ensured that the flat seal ring is elastically and slightly plastically deformable under the action of the operating force. Therefore, a reliable sealing is ensured, for example, even when there are undulations.
[0009]
In a further development of the solution according to the upper claims, the flat seal ring may comprise a plurality of through slits separated from one another by a web in order to constitute a passage system. These through slits create a relatively large cross section leading to the index hole between the upper and lower sides of the flat seal ring, which will be quickly shown when a leak occurs.
[0010]
Another preferred embodiment is that the flat seal ring comprises a circumferential groove on both sides in order to form a passage system, and these grooves are connected to each other by a communication notch penetrating a common groove bottom surface. It is being done. Since the circulating groove is relatively easy to manufacture, the manufacturing cost is relatively low. In addition, reliable stability in the radial direction is ensured by the common groove bottom surface.
[0011]
In particular, a stable flat seal ring is formed by encircling passages on the support surface side in the seating member and the cylinder head so as to constitute a passage system, and these passages are connected to each other by notches in the flat seal ring. Can be achieved.
[0012]
Other preferred embodiments and preferred developments of the solutions described in the superordinate claims are described in the remaining dependent claims and are also detailed in the description of the following embodiments with reference to the drawings. .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The main field of application of the present invention is the cylinder head of a two-cycle large diesel engine. In a two-cycle large diesel engine, an exhaust hole provided in the area of the cylinder head, which can be controlled by an attached exhaust valve, is provided in the cylinder. The basic structure and mechanism of this type of engine are known per se and therefore need not be described in further detail in the context of this description.
[0014]
The cylinder head 1 of the two-cycle large diesel engine shown in FIG. 1 is mounted on a cylinder liner (not shown). The cylinder head 1 includes a central exhaust hole 2 having a relatively large diameter, and an exhaust passage 3 continues to the exhaust hole. The exhaust hole 2 can be opened and closed with respect to the cylinder chamber 5 by an attached exhaust valve 4. The valve head of the exhaust valve 4 is provided with a frustoconical abutment surface 6 on which a seating member 7 inserted into the cylinder head 1 and through which the exhaust passage 2 passes is integrated. A molded, tapered seating surface 8 is provided correspondingly.
[0015]
The cylinder head 1 and the seating member 7 inserted in the cylinder head 1 are integrally held by a fastener (not shown) in detail. In order to transmit the supporting forces facing each other, the cylinder head 1 and the seating member 7 are disposed in the horizontal direction. Support surfaces 9 and 10 are provided. In order to form the support surfaces 9 and 10, the cylinder head 1 includes a stepped portion facing upward, and the seating member 7 includes a stepped portion facing downward. The abutting surfaces 6, 8 of the exhaust valve 4 and the seating member 7 facing each other are exposed to high mechanical and thermal loads. Therefore, an armor portion 11 made of a special material can be provided on these contact surfaces. At the same time, the seating area of the seating member 7 is cooled by the cooling water.
[0016]
For this purpose, a circulating cooling passage 12 is engraved in a region on the upper side of the support surfaces 9 and 10 at the substantially cylindrical joint between the cylinder head 1 and the seating member 7. The cooling passage is constituted by a notch that circulates between the inner periphery of the cylinder head 1 and the outer periphery of the seating member 7 facing each other. As can be seen from the left side of FIG. 1, the cooling passage 12 can be supplied with circulating cooling means that is normally cooled water through a supply pipe line and a discharge pipe line. Similarly, as shown on the left side of FIG. 1, a branch hole 14 extending to the seating region of the seating member 7 extends from the cooling passage 12.
[0017]
The cooling passage 12 is sealed by upper and lower sealing mechanisms in the axial direction. The upper sealing mechanism far from the combustion chamber is configured as an O-ring 15, and this O-ring is inserted into a circulating groove 16 formed in the outer peripheral region of the seating member 7, and Works with a cylindrical inner circumference. In order to constitute a lower sealing mechanism close to the combustion chamber, in the illustrated example, a circulating flat seal ring 17 sandwiched between the support surfaces 9 and 10 is provided, and this flat seal ring is a flat rectangular shape. It has a visible cross section. The thickness of the flat seal ring is about 2 mm. Of course, in addition to the flat seal ring 17, it is also conceivable to provide further sealing means, for example an O-ring arranged in front of the flat seal ring.
[0018]
The flat seal ring 17 arranged between the support surfaces 9, 10 is advantageously made of a relatively soft alloy steel or a soft copper alloy equivalent thereto. In any case, it is important that the material is relatively soft compared to the basic material of the cylinder head 1 or the seating member 7. It is desirable that this material has a property of being elastically deformable under the action of a force generated during operation and plastically deformable to a small extent in terms of strength. As a result, the side contact side surface of the flat seal ring 17 can be firmly in contact with the support surfaces 9 to 10 facing the flat seal ring 17 while maintaining a sealed state. This does not change even when there is a certain degree of surface roughness and / or foreign particles that fall between these surfaces. Thus, the deformability described above facilitates manufacturing and assembly.
[0019]
The flat seal ring 17 ensures a high reliability, but is nevertheless provided with an indicator device that makes it possible to indicate a leak in order to increase certainty. The indicator device includes a passage system 18 provided on the flat seal ring 17 that connects the upper and lower joints between the side contact surfaces of the flat seal ring 17 and the supporting surfaces 9 and 10 facing each other. This passage system is in communication with an indicator hole 19 that terminates on the visible outer surface, shown on the right side of FIG. It is advantageous to provide a plurality of indicator holes 19 that are evenly distributed on the circumference over the entire circumference.
[0020]
These index holes are provided in the seating member 7 here, and terminate in the region above the seating member 7 at the outside in the radial direction of the exhaust passage casing 20 added to the seating member 7. The exhaust passage casing has a flange that surrounds the protruding portion of the seating member 7. Therefore, an annular space 21 that can be seen from the outside is formed in the area of the opening of the index hole 19. Therefore, the liquid that emerges from the index hole 19 into the annular space 21 or the combustion gas that emerges can be quickly discovered if appropriately observed. The leaking liquid that emerges can cause wetting of the engine member surrounding the annular space 21 or the engine room. However, such a case does not actually occur because the reliability of the flat seal ring 17 is high.
[0021]
The flat seal ring 17 may comprise a plurality of arcuate slits 23 separated from each other by a thin web 22, as best seen in FIG. As shown in FIG. 3, it penetrates through the entire thickness of the flat seal ring 17, thereby connecting the lower surface and the upper surface of the flat seal ring to each other. In the embodiment shown in FIG. 2, four arc-shaped slits 23 and four webs 22 each provided in a quadrant are provided. The inner diameter of the arc-shaped slit 23 is about 2 mm when the inner diameter of the flat seal ring is about 200 mm, that is, about 1% of the inner diameter. At this time, the width of the web 22 can also be 2 mm, that is, about 1% of the inner diameter.
[0022]
The arcuate slit 23 is advantageously in the region of the radially inner half of the width of the flat seal ring 17, as can be seen from FIG. Thereby, a wide sealing surface 24 radially outward is produced. Since the arc-shaped slit 23 establishes a connection between the lower side and the upper side of the flat seal ring 17, the leaked liquid or leak gas generated in some cases may be caused by leakage occurring in the region of the lower surface of the flat seal ring 17. Regardless of whether or not it is occurring in the area of, the index hole 19 extending from the upper surface of the flat seal ring 17 is entered.
[0023]
In the embodiment shown in FIG. 4, the flat seal ring 17 includes circumferentially facing grooves 25 on both sides, and these grooves 25 are connected to each other by a hole 27 penetrating a common groove bottom surface 26. In this embodiment, the radial strength is even higher. Again, a relatively wide radially outer sealing surface 24 can be provided. The axial thickness of the flat seal ring 17 is 2 mm, that is, about 1% of the inner diameter. The radial thickness is 26 mm, which is slightly less than 10% of the outer diameter.
[0024]
In the embodiment shown in FIG. 5, the cylinder head 1 and the seating member 7 are provided with a circumferential groove 28 that divides the support surfaces 9 and 10 and is disposed to face each other. Since the flat seal ring 17 is provided with a hole 29 that penetrates the entire thickness thereof, a passage system that connects the lower surface and the upper surface of the flat seal ring is similarly formed, and the indicator hole 19 communicates with the passage system. Can do.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a cylinder head of a cylinder of a two-cycle large diesel engine.
FIG. 2 is a plan view showing a flat seal ring according to the present invention.
3 is a cross-sectional view of the flat seal ring shown in FIG.
FIG. 4 is a cross-sectional view showing another embodiment of a flat seal ring.
FIG. 5 is a cross-sectional view showing still another embodiment of a flat seal ring.

Claims (9)

The cylinder is provided with at least one exhaust hole (2) that can be controlled by the exhaust valve (4), and this cylinder has a cylinder head (1). A seating member (7) provided for the valve (4) and provided with an exhaust hole (2) is inserted, and a region of the joint between the cylinder head (1) and the seating member (7) is cooled. A cooling passage (12) in which an agent can be supplied, a sealing mechanism that closes the cooling passage and is offset from each other in the axial direction, and a support surface (9, 10) that receives mutual support force In a two-cycle large diesel engine, provided on these support surfaces, an indicator hole (19) terminating at the outer surface is provided to indicate leakage,
The sealing mechanism provided for the cooling passage includes a rotating flat seal ring (17) sandwiched between the support surfaces (9, 10), and the flat sealing ring includes the flat rotating ring. A passage system (18) for connecting the side surfaces of the seal ring on the support surface side is provided, and the passage system and the indicator hole (19) communicate with each other.
The flat seal ring (17) is configured as a metal ring,
The flat seal ring (17) independently forms a seal mechanism to be disposed,
The flat seal ring (17) sandwiched between the support surfaces (9, 10) constitutes the sealing mechanism of the cooling passage (12) on the lower combustion chamber side ,
The flat seal ring (17) is separated from each other by a web (22) so as to constitute the passage system (18), and a plurality of arcuate slits (23) extending through the entire height of the flat seal ring. 2-stroke large diesel engine, wherein are <br/> provided with. The cylinder is provided with at least one exhaust hole (2) that can be controlled by the exhaust valve (4), and this cylinder has a cylinder head (1). A seating member (7) provided for the valve (4) and provided with an exhaust hole (2) is inserted, and a region of the joint between the cylinder head (1) and the seating member (7) is cooled. A cooling passage (12) in which an agent can be supplied, a sealing mechanism that closes the cooling passage and is offset from each other in the axial direction, and a support surface (9, 10) that receives mutual support force In a two-cycle large diesel engine, provided on these support surfaces, an indicator hole (19) terminating at the outer surface is provided to indicate leakage,
The sealing mechanism provided for the cooling passage includes a rotating flat seal ring (17) sandwiched between the support surfaces (9, 10), and the flat sealing ring includes the flat rotating ring. A passage system (18) for connecting the side surfaces of the seal ring on the support surface side is provided, and the passage system and the indicator hole (19) communicate with each other.
The flat seal ring (17) is configured as a metal ring,
The flat seal ring (17) independently forms a seal mechanism to be disposed,
The flat seal ring (17) sandwiched between the support surfaces (9, 10) constitutes the sealing mechanism of the cooling passage (12) on the lower combustion chamber side ,
The flat seal ring (17) is provided with grooves (25) on both sides so as to constitute the passage system (18), and these grooves communicate with notches (26) passing through a common groove bottom surface (26). 27) A two-cycle large diesel engine characterized by being connected to each other by 27) . The cylinder is provided with at least one exhaust hole (2) that can be controlled by the exhaust valve (4), and this cylinder has a cylinder head (1). A seating member (7) provided for the valve (4) and provided with an exhaust hole (2) is inserted, and a region of the joint between the cylinder head (1) and the seating member (7) is cooled. A cooling passage (12) in which an agent can be supplied, a sealing mechanism that closes the cooling passage and is offset from each other in the axial direction, and a support surface (9, 10) that receives mutual support force In a two-cycle large diesel engine, provided on these support surfaces, an indicator hole (19) terminating at the outer surface is provided to indicate leakage,
The sealing mechanism provided for the cooling passage includes a rotating flat seal ring (17) sandwiched between the support surfaces (9, 10), and the flat sealing ring includes the flat rotating ring. A passage system (18) for connecting the side surfaces of the seal ring on the support surface side is provided, and the passage system and the indicator hole (19) communicate with each other.
The flat seal ring (17) is configured as a metal ring,
The flat seal ring (17) independently forms a seal mechanism to be disposed,
The flat seal ring (17) sandwiched between the support surfaces (9, 10) constitutes the sealing mechanism of the cooling passage (12) on the lower combustion chamber side ,
The cylinder head (1) and the seating member (7), which are both engaged with each other, have a plurality of passages (28) that circulate on the support surface side so as to constitute the passage system (18). the has two-stroke large diesel engine these passages, characterized by being linked to each other by a notch extending over the entire height of the support ring (17) (29).   Engine according to claim 1, characterized in that the flat seal ring (17) is made of a material that is elastically and slightly plastically deformable under the action of an operating force.   The engine according to claim 1 or 4, wherein the flat seal ring is made of a copper alloy or a soft alloy steel.   The engine according to claim 1, wherein the sealing mechanism of the cooling passage (12) on the side far from the combustion chamber is formed as an O-ring that circulates.   The said seating member (7) is provided with the cooling hole (14) extended from the said cooling channel | path (12) and reaching to a seating area | region in the case of a two-cycle large sized diesel engine. Engine.   When a two-cycle large diesel engine is used, a supply pipe and a discharge pipe (13) provided for the cooling passage (12) are arranged in the cylinder head (1). The engine according to any one of 1 to 7.   In the case of a two-cycle large diesel engine, the index hole (19) is provided in the seating member (7) and is provided in the exhaust passage casing (20) mounted on the seating member (7). The engine according to any one of claims 1 to 8, characterized in that it terminates in a region above the seating member (7) that radially surrounds the contact region.

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