JPH10325317A - Piston type internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piston type natural engine in which a conventional type device is improved by simple and inexpensive means, and high reliability and excellent cooling effect can be obtained even with a simple and inexpensive structure. I do. SOLUTION: A piston type internal combustion engine having at least one piston 2 with a piston rod 3, particularly a large diesel engine. The piston has at least one cooling chamber 8
And the cooling chamber contains a heat transfer agent. The heat transfer agent can be cooled in a cooling device to which the coolant is sprayed. A recess 9 is provided in at least a part of the piston rod 3 in the longitudinal direction. This recess is connected to the cooling chamber 8 of the piston 2 and forms a closed hollow system with the cooling chamber. The hollow system is partially filled with a heat transfer agent, and the piston rod 3 has a cooling surface corresponding to the recess 9 to which a coolant can be sprayed, so that a simple structure and excellent cooling effect can be obtained. Achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston type internal combustion engine having at least one piston having a piston rod, and particularly to a large diesel engine. The piston has at least one cooling chamber, which contains a heat transfer agent. This heat transfer agent can be cooled in a cooling device to which the coolant is sprayed.

[0002]

2. Description of the Related Art A similar arrangement is known from EP 0 074 156. In this known configuration, a heat exchanger closing the lower part of the cooling chamber is provided in the piston. This arrangement is therefore relatively expensive to manufacture and requires additional components. Moreover, the cooling surface obtained by this configuration is relatively small. In addition, the heat exchanger is at risk of breakage due to high load. Therefore, there is a great risk of leakage.

[0003]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to improve a device of the above type by simple and inexpensive means, and to obtain high reliability and excellent cooling effects even with a simple and inexpensive structure. It is to be able to be.

[0004]

The above-mentioned problems are solved by the present invention as follows. That is, the recess is provided in at least a part of the piston rod in the longitudinal direction. The recess is connected to a cooling chamber of the piston and forms a closed hollow system with the cooling chamber. The hollow system is partially filled with the heat transfer agent. In addition, the ston rod
A cooling surface is provided corresponding to the recess, on which a coolant is sprayed.

In the present invention, a piston rod is preferably used as a heat exchanger. Therefore, it is not necessary to use an additional member. The necessary recesses can be easily formed. At the same time a high degree of robustness and safety against leakage are guaranteed. Also, the piston rod has a relatively large heat transfer surface. That is, the piston rod is a relatively long and thick component. In the present invention, the heat transfer agent is moved by the principle of the cocktail shaker by the back and forth movement of the piston and the piston rod, whereby good heat transfer is performed, heat uniformity is excellently performed, and the piston is reliably moved. Is cooled. For the above reasons, the present invention guarantees high efficiency and excellent economy.

[0006] Preferred configurations and further developments of the measures of the main claim are set out in the sub-claims. In this way, the recesses of the piston rod are preferably formed as axial blind holes emanating from the cooling chamber, these recesses reaching the bottom of the piston rod on the cross rod side, away from the piston. . In this way, the recess penetrates over substantially the entire length of the piston rod, and a groove is formed in a suitable manner which extends parallel to the direction of movement of the piston rod. This guarantees a good exchange of the heat transfer agent. Further, a coating as a desirable casing is automatically provided.

In order to provide directionality to the flow and increase the residence time of the heat transfer agent, several recesses of the piston rod may be joined together to form a single through groove. In that case, opposed check valves are provided at the inlet and outlet on the piston side of the groove.

[0008] The recess of the piston rod is suitably provided near the periphery of the piston rod. As a result, the entire relatively large circumferential surface of the piston rod functions as a heat release surface.

In a further preferred embodiment, the piston rod is sprayed with a coolant from the outside via an injection nozzle at least partly in its longitudinal direction. This promotes heat release outside the piston rod and ensures reliable cooling of the heat transfer agent.

[0010] As another preferred means, the piston rod is provided with a cooling groove to which a coolant is sprayed, adjacent to the recess corresponding to the heat transfer agent. As a result, internal heat release is also suitably performed.

The cooling groove is formed as an axial blind hole that emanates from the crosshead-side end of the piston rod. Lubricating oil can be sprayed into this blind hole by a crosshead lubricating oil system. This measure allows a particularly simple implementation with a high cooling effect.

For the purpose of giving a direction to the flow and increasing the residence time of the coolant inside the piston rod, several cooling grooves are connected to each other to form one through groove. A check valve is provided to oppose the inlet and outlet of the valve.

[0013] Further preferred embodiments and further features which are suitable for the purpose of the measures set out in the dependent claims are set out in the dependent claims. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below in detail with reference to the drawings. The following is shown in the drawings. FIG. 1 shows a first embodiment according to a vertical section of the structure of a large two-stroke diesel engine consisting of a piston, a piston rod and a crosshead;
FIG. 3 is a cross-sectional view taken along line II-II in FIG. 1; FIG. 3 is a horizontal cross-sectional view of a piston rod formed of a plurality of members;
FIG. 5 is a sectional view taken along the line VV in FIG. 4 of the second embodiment of the present invention, corresponding to FIG.

[0015] The structure and operation of large two-stroke diesel engines and methods used to drive ships and the like are well known. This type of engine has a plurality of drives each having a piston 2 provided on a corresponding cylinder 1. Said pistons are fixed via piston rods 3 to corresponding crossheads 5 slidably mounted on the engine frame. The piston rod 3 transmits the reciprocal motion of the piston 2 to the crosshead 5. The crosshead is connected to a crankshaft (not shown) provided in a lower region of the engine frame 4 by driving a connecting rod (not shown). The crosshead 5 is a vertical guide 6 of the engine frame 4.
Has a slide shoe that slides up. The slide shoe is supplied with lubricating oil by a lubricating oil device 7.

The head of the piston rod 3 is
Bolts. The bottom of the piston rod 3 is fixed by bolts to a lateral member (Yoch) of the crosshead 5 that bridges the slide shoe. The piston 2 defines a combustion chamber on the upper side, and a relatively thin wall thickness is realized because the inside is cooled. Further, the piston 2 has an internal cooling chamber 8 defined by an upper part by the bottom part of the piston and a lower part by the head of the piston rod 3. A branch pipe formed by a recess 9 provided in the piston rod 3 in the axial direction extends from the internal cooling chamber.
The branch pipe is in this case formed as an axial blind hole which extends substantially the entire length of the piston rod 3 and terminates at the bottom of the piston rod. This axial blind hole is provided on an arc concentric with the axis of the piston rod with the same angular distribution, as shown in FIG. In the illustrated example, 45
Eight recesses 9 are provided which are offset from one another by degrees. These recesses have a slight diameter of 15 to 50 mm, preferably 25 mm.

The cooling chamber 8 and the recess 9 form a hollow system closed to the outside. The hollow system contains a heat transfer agent, such as water or glycol, which is only partially filled and has excellent heat transfer properties, as indicated by the level line 10. The level line 10
The filling level, indicated by, amounts to 60-90% of the volume of this hollow system. During operation of the engine, the back-and-forth movement of the piston 2 and the piston rod 3 produces an effect similar to that seen in a cocktail shaker. Therefore, the exchange of the heat transfer agent contained in the cooling chamber 8 is constantly performed. The heat transfer agent is supplied with heat in the region of the piston 2 and releases it again in the region of the piston rod 3, which ensures that the piston 2 is cooled.

Since the piston rod 3 is a very long and relatively thick component, it has a relatively large outer surface. Through this outer surface, heat released from the heat transfer agent is released to the surroundings. 1 to 3 are based on such an implementation. In this case, the recess 9 of the piston rod 3 is provided in the outer edge region of the piston rod 3 with a slight wall thickness. Accordingly, the corresponding arc also extends near the outer edge. The coolant is sprayed from the outside on the circumferential surface of the piston rod 3 in order to increase the heat release. As the coolant, a lubricant originally used in the natural engine can be used as it is.

For this purpose, as can be seen from FIG. 1, a large number of injection nozzles 11 for spraying a coolant such as lubricating oil are provided one above another, and these injection nozzles are located in the area of the guide 6 of the corresponding crosshead 5. The coolant is sprayed onto the area of the piston rod 3, whereby external cooling takes place.

It is preferable that the injection nozzles 11 are provided so that some of them are opposed to each other on the circumferential side. In the illustrated example, as can be seen from FIG. 2, the guide 6 is provided on both sides, and a nozzle bar having a plurality of overlappingly provided injection nozzles 11 is provided in all areas of the four corners of the shaft through which the piston rod passes. Have been. As a result, the piston rod 3
The coolant is sprayed uniformly over the entire circumference and a relatively large length of the coolant. Said injection nozzles 11 are connected via corresponding supply lines 12 to the corresponding crosshead lubricating oil devices 7, whereby the supply of the cooling liquid takes place in a simple manner. Oil injected into the piston rod 3 to cool the piston rod 3 is easily discharged to the crank chamber. With a simple configuration, it is sufficient here to apply cooling air to the piston rod 3.

The recess 9 is formed simply as a blind hole. This manufacturing method poses a problem when the piston rod 3 is formed integrally. In the embodiment according to FIG. 3, the piston rod 3 comprises an inner core 14 which is surrounded by a sleeve 15. In this case, the inner core 14 and / or the sleeve 15 are provided with grooves in the region of their outer peripheral surface or inner peripheral surface to form the recess. The grooves are provided from the casting stage, and then are finish-cut or formed entirely by cutting.

Alternatively, some or all of the recesses of the piston rod 3 are respectively connected to one another in a distal region remote from the lower piston, as indicated by the dashed line 16 in FIG. As a result, a through groove having a branch for advancing and returning is provided. In the area of the through-groove inlet or outlet, a check valve 17 or 18 in the opposite direction is provided as further shown by a broken line in FIG. These check valves are opened only in the inflow direction or only in the outflow direction. In this way, the flow is directed. The combination of the recesses to form a single groove also increases the residence time of the heat transfer agent in the area of the piston rod 3, thereby improving the cooling effect as a whole. Furthermore, in such an embodiment, the filling level of the closed system comprising the cooling chamber 8 and the recess 9 is relatively high.

In the embodiment according to FIGS. 4 and 5, the piston rod 3 is internally cooled. For this purpose, a recess 19 is provided adjacent to the recess 9 of the piston rod 3 emanating from the cooling chamber 8. These recesses 19 function as cooling grooves into which a coolant such as lubricating oil is sprayed. These recesses 19 are provided on an arc concentric with the arc of the recess 9 as can be seen from FIG. In the illustrated embodiment, the recess 9 emanating from the cooling chamber 8 is provided on an inner arc, and the recess 19 forming the cooling groove is provided on an outer arc.

The recess 19 that forms the cooling groove is formed as a blind hole that emanates from the end of the piston rod 3 on the crosshead side. The blind hole reaches the head of the piston rod 3 and terminates at the head of the piston rod below the end face of the piston rod defining the cooling chamber 8. The recess 19 may be formed as a blind hole like the recess 9, but may be formed as shown in FIG. 3. In that case, two jackets would be needed. The recess is simply connected to the corresponding lubricating oil device 7 of the crosshead 5 for supplying lubricating oil to the recess 19 serving as a cooling groove. For this purpose, the crosshead 5 is provided with a branch pipe that communicates with the recess 19 whose crosshead side is open.

In order to extend the residence time of the lubricating oil and give direction to the flow, some or all of the cooling grooves are connected to each other so that an inlet and an outlet on the crosshead side are formed. It is also possible to The same is true for the recess 9 emanating from the cooling chamber 8. As already described in detail with respect to FIG. 1, the recesses can be connected to each other such that an inlet and an outlet on the piston side are provided, respectively, and the recesses 17 and 18 of FIG. As shown in the figure, a check valve in the opposite direction is provided. In the region of the groove formed by the recesses 19 connected to one another, there is already a hydraulically directed flow, so that only one non-return valve or no non-return valve is required.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a structure of a large two-stroke diesel engine according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG.

FIG. 3 is a horizontal sectional view of a piston rod according to the present invention formed from a plurality of members.

FIG. 4 is a longitudinal sectional view of a structure of a large two-stroke diesel engine according to a second embodiment of the present invention.

FIG. 5 is a sectional view taken along line VV in FIG. 4;

[Explanation of symbols]

 2 Piston 3 Piston rod 5 Crosshead 8 Cooling chamber 9, 19 Recess 11 Injection nozzle 14 Inner core 15 Sleeve 17, 18 Check valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16C 5/00 F16C 5/00

Claims (19)

[Claims] 1. At least one piston (2) with a piston rod (3), said piston having at least one cooling chamber (8), said cooling chamber containing a heat transfer agent, A piston type internal combustion engine, particularly a large diesel engine, in which the heat transfer agent can be cooled in a cooling device into which a coolant is sprayed, wherein at least a part of the piston rod (3) is recessed in a longitudinal direction. Wherein the recess is connected to the cooling chamber (8) of the piston (2) to form a closed hollow system with the cooling chamber, wherein the hollow system is partially connected to the heat transfer A piston type internal combustion engine, characterized in that the piston rod (3) is filled with an agent and has a cooling surface corresponding to the recess to which the coolant is sprayed. 2. The recess (9) of the piston rod (3).
2. A piston-type internal combustion engine according to claim 1, wherein the piston is formed as an axial blind hole extending from the cooling chamber. 3. The recess (9) of the piston rod (3).
3. The piston type internal combustion engine according to claim 1, wherein the piston reaches a crosshead-side bottom of the piston rod, which is separated from the piston. 4. 4. The recess (9) of the piston rod (3).
Piston internal combustion engine according to any of the preceding claims, characterized in that at least some of them are connected to each other at least in an end region remote from the piston. 5. A check valve (17,1) having an opposite direction is provided at an inlet and an outlet on the piston side of the recess (9) connected to each other.
The piston type internal combustion engine according to claim 4, wherein (8) is provided. 6. The method according to claim 1, wherein the recess is provided on an arc concentric with the axis of the piston rod. Piston type internal combustion engine. 7. The piston rod (3) according to claim 1, wherein the recess (9) is provided near an outer edge of the piston rod (3), and an outer surface of the piston rod is coolable. The piston-type internal combustion engine according to 1. 8. The piston type internal combustion engine according to claim 7, wherein at least a part of the piston rod in a longitudinal direction is sprayed with a coolant from outside by an injection nozzle. 9. A plurality of injection nozzles (11) provided in multiple stages, respectively, are arranged in corner regions of the shaft corresponding to the piston rods (3), respectively. A piston-type internal combustion engine according to claim 1. 10. The piston type internal combustion engine according to claim 1, wherein the injection nozzle (11) is capable of injecting lubricating oil through a lubricating oil system on the engine side. 11. The piston rod (3) is provided with a recess (19) adjacent to the recess (9) corresponding to the heat transfer agent, to which a coolant can be sprayed. The piston type internal combustion engine according to claim 1. 12. The piston-type internal combustion engine according to claim 11, wherein the recess (19) is provided on an arc concentric with the axis of the piston rod (3). 13. The piston type internal combustion engine according to claim 11, wherein the recess (19) is formed as a blind hole emanating from a crosshead-side end of the piston rod (3). . 14. The piston according to claim 1, wherein the recess extends in the longitudinal direction of the piston rod to a position slightly short of a piston-side end of the piston rod. The piston type internal combustion engine according to any one of items 11 to 14. 15. Lubricating oil is sprayed into said recess (19) via a lubricating oil device (7) provided in said crosshead (5).
A piston type internal combustion engine according to any one of the above. 16. A piston-type internal combustion engine according to claim 11, wherein the recesses (19) are connected to one another at least at least at the piston end. 17. The piston-type internal combustion engine according to claim 16, wherein a check valve is provided in the recess connected to each other in the crosshead-side inlet area. 18. The recess (9) of the piston rod (3).
The piston type internal combustion engine according to any one of claims 1 to 17, wherein at least a part of (19) is formed as an axial through hole. 19. The piston rod (3) comprises an inner core (14) and at least one sleeve (15) surrounding the inner core, wherein the piston rod (3) has a recess (9 or 19). At least part of the inner core (1
A piston-type internal combustion engine according to any of the preceding claims, characterized in that it is formed as a recess on the circumferential side of the sleeve (4) and / or the sleeve (15).