JP3444606B2 - Reciprocating piston diesel engine cooling system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder cooling device in a reciprocating piston type diesel internal combustion engine, wherein the cylinder cooling device is at least one cylinder arranged in a cylinder block. After having passed through the cylinder head, having an insert, surrounded by an annular chamber passed by the refrigerant, and straddled by a cylinder head passed by the refrigerant coming from the annular chamber, The present invention relates to a device for cooling a cylinder that returns to an annular chamber via a cooler.

[0002]

In this type of apparatus, the bulk of the refrigerant coming from the chiller first passes through the annular chamber, then through the refrigerant duct in the upper end of the cylinder insert as far as possible, and finally. Passes through the cylinder head. The amount of refrigerant is such that when the engine is under 100% load, the temperature of the inner surface of the cylinder insert, which surface forms the sliding surface for the piston, is always above the dew point of water. Has been adjusted to be This is due to the fact that sulfurous acid (H ₂ SO ₃ ) and sulfuric acid (H ₂ SO ₄ ) (depending on the high sulfur content of the fuel currently used in diesel engines ... 4% or more ...) It prevents the walls from being corroded. Of the two acids mentioned above, sulfurous acid is not particularly preferred. Because of the SO ₂ needed to form the combustion products, namely the sulfurous acid.
Occurs at lower temperatures and in greater amounts than the SO ₃ required to form sulfuric acid. Also, the sulfuric acid condensate, which produces only a small amount, can be neutralized with a lubricating additive. If the temperature drops below the dew point, it is therefore prone to significant condensation, which in turn destroys the lubricating oil film and causes the cylinder to
Adhesion wear on the sliding surfaces of the inserts and corrosion wear on the sliding surfaces of both the piston ring and cylinder inserts. When operating a piston type engine at partial load, the temperature easily drops below the dew point in known devices.

[0003]

It is an object of the present invention to provide a cooling device of the type described above in such a way that the formation of sulphurous acid is reliably prevented even when the engine is running at partial load. Is to improve.

[0004]

This object is the present invention, in which the conduit leading from the cooler to the annular chamber branches from the conduit leading to the cylinder head. , Equipped with a controller, which divides the amount of refrigerant coming from the cooler into a line leading to the annular chamber and a line leading to the cylinder head, depending on the load on the engine, and Pipe line connecting to the cylinder head The bypass line leading to the pipe line connecting the downstream section of the section to the annular chamber is connected to the refrigerant line between the cylinder head and the cooler. It is achieved by the present invention. The conduit leading to the cylinder head supplies some refrigerant directly to the cylinder head during engine operation.
At the lower temperature than in the known device and at a higher temperature than in the known device, the remaining refrigerant is supplemented by the amount flowing into the annular chamber and fed along the bypass line. Some residual refrigerant now provides a slightly lesser degree of cooling in the annulus as the sliding surface temperature rises. This ensures that at all engine loads the temperature does not drop below the dew point and hence no sulfite is formed. The sliding surfaces of the cylinder insert and the piston ring are therefore no longer subject to corrosion.

Embodiments of the present invention will now be described in more detail by way of example with reference to the drawings.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cylinder block 1 of a multi-cylinder reciprocating piston type diesel internal combustion engine, a cylinder insert 2 installed in the cylinder block 1 with its upper end protruding, and a cylinder The cylinder head 3 straddling the insert 2 is illustrated. The three cylinder parts described above are liquid refrigerants, such as water,
Therefore, it is cooled by the liquid refrigerant equipped with the main circulation line 5 and the secondary circulation line 13 for the refrigerant. The main circulation pipe line 5 is a pipe line 6, which communicates from the cylinder head 3 to a cooling machine 7 connected to the pipe line 6, a refrigerant pump 8, and the cooling machine 7 to the cylinder block 1. It contains a conduit 6 leading to a conduit 9. Inside the cylinder, there is a flow (shown in dotted lines) between the connecting section for the line 9 above the cylinder block 1 and the connecting section for the line 6 above the cylinder head 3. There is a path 10 and is described in more detail below with reference to FIG. The main circulation line 5 further contains a bypass line 11 that bypasses the cooler 7. Where the bypass line 11 branches off from the line 6, there is a distribution valve 12, which comes from the cylinder head 3 and the main circulation line 5
There is a distribution valve that branches the refrigerant flowing into the inside into an amount that flows into the cooler 7 and an amount that flows through the bypass line 11 depending on the temperature of the refrigerant. Between the cooling pump 8 and the cylinder block 1, the line 9 further contains a distribution valve 17. In the line 6 between the cylinder head 3 and the distributor valve 12 and then the distributor valve 17 and the cylinder block 1
There are distribution lines 6 ', 9'in the line 9 between and to which the remaining cylinders (not shown) of the engine are connected.

The secondary circulation line 13 is a line 15 which contains the refrigerant pump 14 and which branches from the distribution line 6'and leads to the distribution line 9 '. Contains. A line 16 emerges from the distributor valve 17, which is provided with a distribution line 16 'which leads directly to the cylinder head 3 and which corresponds to the distribution lines 6'and 9', respectively. The distribution valve 17 is a controller 18, which sends a setting signal to the signal line 19 according to the load of the engine.
It is under the control of the controller 18 which receives from In addition to the setting signal, the controller is at least one actual operating value signal, which actual operating value signal is directly or indirectly dependent on the temperature of the sliding surface of the cylinder insert 2 and by the signal line 20. Receives the operational value signal provided.

As shown in FIG. 2, the lower half of the cylinder insert 2 is the cylinder block 1,
The cylinder blocks are separated by a wall 1 ',
It projects into a cylinder block 1 having an upper chamber 22 through which the refrigerant passes and a lower chamber 23 through which the scavenging air passes. The insert 2 has a plurality of scavengers 24 located below it and distributed around it, with a vertically operating piston 50 (indicatively indicated by its top dead center TDC) at its bottom dead center. It has a plurality of scavengers 24 that take scavenging gas from the scavenging chamber 23 into the insert when the scavenging ports 24 near the BDC are exposed. Insert 2,
The sliding surface of the insert is designed as 2'cylinder in which the insert 2 has a cylinder head 3 at its upper end, in which a disc-shaped exhaust valve 25 is mounted approximately in the center of the insert.・ Head 3 is equipped. In the cylinder head 3,
Although the head 3 starts from a valve seat that cooperates with the exhaust valve 25, there is an exhaust hole 26 through which the valve 25
Exhaust gas is expelled by the rising piston 50 when is opened. The illustrated piston is therefore
It is a two-stroke internal combustion engine with vertical scavenging. A two-stroke internal combustion engine may be used to drive a ship or drive a generator. In addition to the exhaust hole 26, the cylinder head 3 is a chamber 2 through which the refrigerant passes.
It contains 7,28.

A sleeve 3 is provided between the cylinder insert 2 and a hole 51 for receiving it in the cylinder block 1.
There is 0, which extends approximately beyond the central portion of the insert and approximately half the length of the insert. The sleeve has an annular shoulder on its outer surface which projects slightly so that it rests against the shoulder of the bore 51. The lower end of the sleeve 30 is mounted by a ring 31 on the insert with a gap. Near the upper end of the sleeve 30, the insert 2 is somewhat thicker, resulting in a narrow annular gap 32 between the upper end of the sleeve 30 and the approaching outer surface of the insert {Fig. 2 (b)}. . Due to this arrangement, an annular intermediate space 33 is formed between the sleeve 30 and its associated part of the insert 2 which is essentially filled with stagnation refrigerant. By adjusting the dimensions of the annular gap 32, it is possible to preset the temperature of the refrigerant in the intermediate space 33 within certain limits. Intermediate space 33 can also be receive a weak flow, for its (Figure 1) valve 3
3 'is equipped in the discharge line which is connected to the intermediate space. The valve 33 'is faster to empty the intermediate space 33.

The cylinder block 1 has in its wall above the chamber 22 a coolant supply conduit 34, to which the end of the conduit 9 coming from the distribution conduit 9'is shown. Not linked in any way. The cylinder insert 2 has a thicker, collar-shaped upper end which contains the known diagonal cooling holes 35 equally spaced above the periphery of the insert. Between the collar and thicker underside of the insert 2 and the cylinder block 1 there is a bearing ring 36 which results in an annular chamber 37 between itself and the insert 2 and between itself and the sleeve. Three
An annular chamber 38 is formed between it and the upper half of 0. The refrigerant from line 9 therefore flows along the refrigerant supply conduit 34 first to the annular chamber 38, then to the annular chamber 37 and from there to the cooling holes 35 in the collar and thicker.

At the upper end of the cooling hole 35, the cooling hole 35 is directed radially outwardly and is connected to a line 39 leading to the chamber 27 in the cylinder head 3. Further connected to line 39 is line 16, which branches off from line 9 at distribution valve 17.

During operation of the reciprocating piston type engine, the refrigerant heated in the cylinder flows through the line 6 and the distribution valve to the cooler 7, where the heat absorbed therein is, for example, the secondary circulation pipe. It is released to seawater flowing in the road. The coolant thus cooled is distributed by the pump 8 along the line 9 to the cylinder block 1 and along the line 16 to the cylinder head 3. The amount of refrigerant flowing to the cylinder block 1 and the cylinder head 3 is set by the distribution valve 17 which is controlled by the controller 18 by the load. The refrigerant flowing to the cylinder block 1 via line 15 in the secondary circulation line 13 is always accepting a small amount of refrigerant at a higher temperature, since it was not cooled in the cooler 7.

The refrigerant flowing to the cylinder block 1 first passes along the conduit 34 first through the annular chamber 38. Due to the stagnant refrigerant in the intermediate space 33, a moderate heat transfer from the cylinder insert 2 to the refrigerant takes place here. The heat transfer is stronger in the annular chamber 37 above the sleeve 30. This is because the flowing refrigerant comes into contact with the cylinder insert 2. The same applies again when the refrigerant passes through the cooling holes 35. Chamber 2 in the cylinder head 3 after it has left the cooling holes 35
Prior to entering 7, the reheated refrigerant receives a mixture of chiller refrigerant from line 16 into line 39.

[0014]

With the line arrangement shown in FIG. 1, therefore, the cylinder block 1 is relatively warm due to the mixture of refrigerants from line 15, and therefore correspondingly at the insert 2. Accepts a reduced amount of refrigerant that reduces cooling activity. The chamber 27 in the cylinder head 3, on the other hand, is always supplied with the full amount of refrigerant at a relatively low temperature. In addition to reducing cooling activity by the addition of refrigerant from line 15, dampening cooling activity is achieved by the distribution valve 1
7 via load-dependent regulation of the amount of refrigerant. In this way, the temperature at the sliding surface 2'of the insert 2 is higher than in the case of known cooling. This is 100%
It is clear from FIG. 3 for the engine load of. In FIG. 3, the solid line B represents the temperature of the sliding surface in the case of the known cooling, while the dash-dotted line C represents the sliding surface temperature for the device embodying the invention. The dotted line D represents the dew point temperature of water. The course of line C therefore shows a significant difference between the sliding surface temperature and the dew point temperature. Since line B is close to dew point line D, when the engine is operating at partial load, the sliding surface temperature shifts to the right in FIG. It drops below the dew point temperature D as shown for 50% load in FIG. In the new cooling system, on the contrary, the sliding surface temperature (line C) remains above the dew point line D, even under partial load.

The design of the cylinder block, cylinder insert and bearing ring illustrated in FIGS. 3 and 4 is as in the prior art.

In contrast to the embodiment shown in FIG. 1, the pump 8 of the main circulation line may be arranged in the line 6 upstream of the distribution valve 12 and the second circulation line 13 Pipeline 1
5 may in turn be branched from between valve 12 and this pump. In this case, the pump 14 for the second circulation line may be opened and replaced by a constriction in line 15.

When the engine is equipped with an exhaust turbine supercharger, some of the refrigerant from the main circulation line 5 may be used to cool the exhaust turbine supercharger like the engine. For this purpose, the refrigerant line containing the exhaust turbine supercharger is the refrigerant pump 8 and the distribution valve 17
It may also branch off from the line 9 between and and lead to the distribution line 6 '.

[Brief description of drawings]

FIG. 1 is a flow chart for a refrigerant in a diagrammatically represented cylinder.

FIG. 2A is an axial sectional view showing a part of the cylinder of FIG. 1 by cutting. (b) is an enlarged detailed view of part b of FIG. 2 (a).

FIG. 3 is a temperature plot depicting temperature versus cylinder insert height at 100% load.

FIG. 4 is a temperature plot depicting temperature versus cylinder insert height at 50% load.

[Explanation of symbols]

1 cylinder block 1'wall 2 cylinder insert 2'sliding surface (of insert) 3 cylinder head 5 Main circulation line 6 pipelines 6'min pipe (to other cylinder) 7 cooler 8 Refrigerant pump 9 pipelines (for main circulation pipeline) 9'minute pipe line (to other cylinder) 10 channels 11 Detour pipeline 12 distribution valves 13 Second circulation line 14 Refrigerant pump 15 pipelines (for second circulation pipeline) 16 pipelines 17 distribution valve 18 Controller 19 signal lines 20 signal lines 22 Upper chamber 23 Lower chamber 24 Scavenger 25 disk type exhaust valve 26 Exhaust hole 27 rooms (in the head) 28 rooms (in the head) 30 sleeves 31 ring 32 Narrow annular gap 33 Intermediate space 33 'discharge valve 34 conduit (refrigerant supply) 35 cooling holes 36 bearing ring 37 Ring room 38 annular chamber 39 conduits (block → head) 50 pistons 51 receiving hole B Sliding surface temperature (known art) C Sliding surface temperature (invention) D dew point temperature

Claims (2)

(57) [Claims] 1. A device for cooling a cylinder in a reciprocating piston type diesel internal combustion engine, the device for cooling a cylinder being surrounded by an annular chamber arranged in a cylinder block and passed by a refrigerant. And at least one cylinder insert straddled by a cylinder head that is passed by a refrigerant coming from the annular chamber, the refrigerant passing through the cylinder head and then passing through the cooler through the annular chamber. In the device for cooling a cylinder, a pipe communicating from the cooler to the cylinder head through the annular chamber branches to a pipe communicating to the cylinder head without passing through the annular chamber. , the controller is equipped such controller pipe and the annular chamber that communicates with the cylinder head through the annular chamber in response to the amount of the refrigerant coming from the condenser to the load on the engine Divided into a conduit that communicates with the cylinder head not through, bypass road line is, cylinder heads
Connected to the pipe between the cooling device and the cooling machine, and via an annular chamber.
Through the annular chamber to the pipe leading to the cylinder head.
Without branching into the conduit leading to the cylinder head
Is connected downstream of the cooler and the branch point.
Device. 2. The device of claim 1, wherein the cylinder insert is surrounded by a sleeve in its central portion, the sleeve being approximately half the length of the insert, and the sleeve being A space between itself and the insert results in an annular intermediate space, which communicates with the annular chamber via a constriction near the upper end of the sleeve and which in turn during engine operation. A device characterized by being filled with an inert refrigerant.