JPH0826812B2 - Engine spacer with cylinder liner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Object of the Invention (Industrial field of application) An engine spacer provided with a cylinder liner according to the present invention is used in a diesel engine for running a truck or a bus or for propelling a ship. The compression ratio of the engine is increased by closing the gap existing between the upper surface of the cylinder liner fitted in the cylinder hole of the cylinder block and the lower surface of the cylinder head to improve the combustion efficiency of the engine.

(Prior Art) A piston type engine is used for various purposes, but in the case of a diesel engine used for running a truck or a bus or for propelling a ship, the inside of a cylinder hole formed in a cylinder block. A cylinder liner is often fitted on.

That is, as shown in FIG. 6, in the cylinder block 1 of the engine, a cylinder hole 3 having a large diameter portion 2 having an inner diameter larger than that of the other portion is formed in the upper end opening portion, and the inside of the cylinder hole 3 is formed. A cylinder liner 5 is fitted inside the piston 4 such that the piston 4 is movable in the axial direction of the piston.

The outward flange 7 provided on the outer peripheral surface of the upper end portion of the main body portion 6 of the cylinder liner 5 formed in a cylindrical shape is fitted into the large diameter portion 2 formed on the upper end portion of the cylinder block 1, and is inserted into the cylinder hole 3. Positioning of the cylinder liner 5 is attempted.

Airtightness and liquid-tightness between the upper surface of the cylinder block 1 and the lower surface of the cylinder head 8 which is fixed to the upper surface of the cylinder block 1 and closes the upper end opening of the cylinder hole 3 are formed in a flat plate shape as a whole. Cylinder head gasket having a bore hole 9 formed at a position aligned with the upper end opening of the hole 3.
Holding by ten.

At the inner peripheral edge of the bore hole 9 of the cylinder head gasket 10, a grommet 11 formed by folding a thin metal plate such as a stainless steel plate into a U-shaped cross section is attached, and the cylinder head gasket 10 is attached to the upper surface of the cylinder block 1 and the cylinder. When strongly pinched with the lower surface of the head 8, the bore hole 9
The pressing force of the part becomes particularly large, and the airtightness in the cylinder chamber where the pressure becomes high can be surely achieved. 18
Is a wiring attached inside the grommet 11 in order to further improve the pressing force of the grommet 11 portion.

(Problems to be Solved by the Invention) However, in the engine seal portion provided with the cylinder liner configured as described above, the following problems conventionally occur.

That is, the upper surface of the cylinder block 1 and the cylinder head 8
Cylinder head gasket 10 to be clamped between the bottom surface of
As described above, the pressing force is particularly high at the grommet mounting portion of the bore hole 9 portion, but the point where this pressing force acts is more than that of the outward flange 7 as shown in the range A in FIG. When the cylinder liner 5 is present on the inner peripheral side portion, the cylinder liner 5 is lowered by the pressing force by the root portion of the outward flange 7 (arrow portion B in FIG. 6), and this bottom portion is supported. A considerably large stress is applied.

In this way, when a large stress is applied to the root portion of the outward flange 7 for a long period of time, a crack may occur in this root portion, and the upper end portion of the cylinder liner 5 may eventually break.

Therefore, conventionally, the inner diameter of the grommet 11 is made sufficiently larger than the inner diameter of the cylinder liner 5, and the grommet 11 is brought into contact with the upper surface of a portion of the outward flange 7 which is relatively near the outer periphery, so that the grommet 11 can be inserted into the cylinder liner 5. The point of pressing the upper surface of the cylinder liner 5 is located outside the outer peripheral surface of the main body portion 6 of the cylinder liner 5.

However, when the inner diameter of the grommet 11 is increased in this way, the portion located on the inner peripheral side of the grommet 11 between the lower surface of the cylinder head 8 and the upper surface of the cylinder liner 5 (the slanted grid portion in FIG. 6). ), A gap is formed.

This gap is the piston 4 fitted inside the cylinder liner 5.
Since the volume does not change with the rise and fall of the engine, not only the compression rate of the engine decreases but the incomplete combustion region expands. For this reason, the existence of the above-mentioned gap lowers the combustion efficiency, increases the amount of carbon fine particles contained in the exhaust gas, and deteriorates the engine performance.

In order to eliminate such inconvenience, the present applicant has previously proposed a filler 12 for closing the space between the lower surface of the cylinder head 8 and the upper surface of the cylinder liner 5 (Japanese Utility Model Application No. 61-039797).
issue). As the filler 12 according to this prior invention, as shown in FIG. 7, a stainless steel filament knitted wire mesh bundled in a rope shape is formed into an endless ring, or as shown in FIG. In addition, a ring-shaped heat-resistant metal plate formed in a corrugated cross section, or a gasket sheet mainly composed of carbon or asbestos as shown in FIG. 9 is used.

However, in the filler disclosed by the above-mentioned prior application, the heat resistance is insufficient depending on the use conditions (examples in FIGS. 7 and 9), or the gap is not completely closed, or it is not always sufficient. I couldn't get the effect.

Therefore, as shown in FIG. 5, the inventor of the present invention, as shown in FIG.
It was considered that the above-mentioned gap (oblique grid portion in FIG. 6) is closed by the spacer 15 consisting of. In the case of such a spacer 15,
Although the heat resistance and the efficiency of closing the gap are improved, there are still the following problems to be solved.

That is, the spacer 15 is the cylinder head gasket 10.
The cylinder head gasket 10 is used while it is fitted inside the bore hole 9 of the cylinder block before the cylinder head gasket 10 is mounted between the upper surface of the cylinder block 1 and the lower surface of the cylinder head 8. It cannot be locked inside the bore hole 9. For this reason, the spacer 15 and the cylinder head gasket 10 cannot be handled as one body, and the parts management and the assembly work to the engine must be complicated. A part of the outer ring 14 is extended in the outer peripheral direction as shown by the chain line in FIG. 5, and the outer peripheral surface of this extension portion 19 and the grommet 11
Although the cylinder head gasket 10 and the spacer 15 can be integrally handled by adhering the inner peripheral edge thereof with an adhesive, it is inevitable that the adhering work is troublesome. When the extension portion 19 is not provided on the outer ring 14, it is particularly difficult for the outer peripheral edge of the spacer 15 and the inner peripheral edge of the grommet 11 to come into close contact with each other, and it is difficult to fix the spacer 15 with an adhesive.

The engine spacer provided with the cylinder liner of the present invention eliminates any of the above-mentioned inconveniences.

b. Structure of the Invention (Means for Solving the Problem) The engine spacer provided with the cylinder liner of the present invention is formed in the cylinder block and has an inner diameter similar to that of the filler in the above-mentioned prior invention. A cylinder liner for internally movably fitting a piston is fitted inside a cylinder hole having a large-diameter portion that is larger than the other portion in the upper end opening, and the main part of the cylinder liner formed in a cylindrical shape is fitted. The outward flange provided on the outer peripheral surface of the upper end portion is fitted into the large diameter portion of the cylinder hole, and the airtightness and the liquidtightness between the upper surface of the cylinder block and the lower surface of the cylinder head are formed in a flat plate shape as a whole. Cylinder head provided with a cylinder head gasket having a bore hole formed at a position aligned with the upper end opening of the cylinder hole. Used to block the gap formed between the surfaces.

The engine spacer provided with the cylinder liner of the present invention comprises an inner ring made of a thin metal plate having a U-shaped cross-section that is open on the inner peripheral side, and an outer ring made of a thin metal plate that surrounds the inner ring and is open on the outer peripheral side. .

Further, the engine spacer provided with the cylinder liner of the present invention has at least two locations on the outer peripheral edge of the outer ring,
A locking tongue is provided as a recess which can be fitted to the inner peripheral edge of a grommet mounted on the inner peripheral edge of the bore hole formed in the cylinder head gasket.

(Operation) The engine spacer provided with the cylinder liner of the present invention configured as described above is applied to the cylinder head gasket while elastically deforming the locking tongues provided at three or more outer peripheral edges of the outer ring. Push it into the inside of the grommet attached to the inner peripheral edge of the formed bore hole. When the spacer is completely pushed into the grommet in this way, the inner peripheral edge of the convexly curved grommet and the outer peripheral side surface of each of the locking tongues that are concavely curved contact each other, and the spacer is placed inside the grommet. To support.

In this way, the engine spacer provided with the cylinder liner of the present invention supported inside the grommet has the above-mentioned grommet space between the lower surface of the cylinder head and the upper surface of the cylinder liner, similar to the filler in the previous invention. The gap located on the inner peripheral side is closed to prevent the gas existing inside the cylinder liner from entering this gap, and to prevent the compression ratio of the engine from decreasing due to the presence of the above-mentioned gap. The complete combustion region is reduced to prevent engine efficiency from deteriorating and to reduce carbon particulates contained in exhaust gas.

(Example) Next, the present invention will be described in more detail with reference to the illustrated example.

1 to 3 show a first embodiment of the present invention.
The drawing is a cross-sectional view showing a state in which the spacer is assembled to the engine together with the cylinder head gasket, FIG. 2 is a partially cut perspective view of the spacer, and FIG. 3 is a plan view of the spacer.

The spacer 15 is composed of an inner ring 13 made of a thin metal plate and having a U-shaped cross section that is open on the inner peripheral side, and an outer ring 14 made of a thin metal plate that is open on the outer peripheral side and encloses the inner ring 13.

Further, the spacer 15 is provided at at least two positions (8 positions in the illustrated example) on the outer peripheral edge of the outer ring 14.
Locking tongue pieces 16 and 16 for supporting the inner peripheral edge of the grommet 11.
Are formed at equal intervals in a state in which the locking tongue pieces 16, 16 project to the outermost peripheral side. An outer peripheral surface side of each locking tongue piece 16, 16 is formed as a curved concave portion 17 so as to be freely fitted into an inner peripheral edge of a grommet 11 mounted on an inner peripheral edge of the bore hole 9 formed in the cylinder head gasket 10. There is.

The spacer 15 of the present invention in which the eight locking tongue pieces 16 and 16 are formed on the outer peripheral side as described above is elastically deformed toward the inner peripheral side of the respective locking tongue pieces 16 and 16 while It is pushed into the inside of the grommet 11 attached to the inner peripheral edge of the bore hole 9 formed in the cylinder head gasket 10. When the spacer 15 is completely pushed into the grommet 11 in this manner, the locking tongue pieces 16 and 16 face outward when the spacer 15 and the cylinder head gasket 10 are in the same plane. The inner peripheral edge of the grommet 11 that is elastically restored and curved in a convex shape and the concave portions 17 and 17 of the outer peripheral side surfaces of the locking tongue pieces 16 and 16 that are concavely curved contact each other. In this state, unless a strong force is applied to the spacer 15 in the direction of extracting the spacer 15 from the inside of the grommet 11, the spacer 15 does not come off from the inside of the grommet 11, and the spacer 15 does not come off.
Supported inside.

Such a spacer mounting operation on the inside of the grommet can be easily performed only by pressing the spacer 15 placed according to the grommet 11 toward the inside of the grommet 11 with a press or the like.

In this way, the engine spacer 15 provided with the cylinder liner of the present invention supported inside the grommet 11 is located on the inner peripheral side of the grommet 11 between the lower surface of the cylinder head 8 and the upper surface of the cylinder liner 5. The gas that exists inside the cylinder liner 5 is prevented from entering the gap by blocking the gap that is formed, suppressing the decrease in combustion efficiency of the engine and reducing the carbon fine particles contained in the exhaust gas.
As described above.

 Next, FIG. 4 shows a second embodiment of the present invention.

In this embodiment, the spacers 15 are formed at the same time that the protrusions 20 are formed on the inner peripheral edge of the upper surface of the cylinder liner 5.
The cross-sectional shape of is changed.

That is, the inner ring 13 and the outer ring 14 that form the spacer 15
And the thickness of the locking tongue 16 formed on the outer peripheral edge of the outer ring 14 is reduced to match the height of the gap to be closed by the spacer 15, and the size of the grommet 11 is Accordingly, the size is the same as that of the first embodiment.

Other configurations and operations are the same as in the case of the first embodiment described above.

c. Effects of the Invention The engine spacer provided with the cylinder liner of the present invention is configured and operates as described above, and therefore the effect of preventing damage to the cylinder liner is left as it is, and the performance of the engine provided with the seal portion is maintained. It is possible to further improve the effect of the invention of the previous invention, which means that the spacer can be improved, and the spacer and the cylinder head gasket can be integrally handled without requiring special manufacturing work. It plays a large role in facilitating and simplifying assembly.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show a first embodiment of the present invention, FIG. 1 is a sectional view showing a state where a spacer is assembled with a cylinder head gasket in an engine, and FIG. 2 is a spacer. FIG. 3 is a partially cutaway perspective view of FIG. 3, FIG. 3 is a plan view of the spacer, FIG. 4 is a view similar to FIG. 1 showing a second embodiment of the present invention, and FIG. 5 shows a structure which is the basis of the spacer of the present invention. Sectional views, FIG. 6 is a sectional view showing a part of an engine provided with a cylinder liner to which the spacer of the present invention is attached, and FIGS. 7 to 9 show three examples of fillers for closing the gap according to the previous invention. FIG. 3 is a sectional view similar to FIG. 1. 1: Cylinder block, 2: Large diameter part, 3: Cylinder hole, 4: Piston, 5: Cylinder liner, 6: Main body part, 7: Outward flange, 8: Cylinder head, 9: Bore hole, 10: Cylinder head gasket , 11: grommet, 12: filler, 13: inner ring, 14: outer ring, 15: spacer, 16: locking tongue, 17: concave, 18: wiring, 19: extension, 20: convex.

Claims (1)

[Claims] 1. A cylinder liner for internally movably fitting a piston is fitted inside a cylinder hole formed in a cylinder block and having a large-diameter portion having an inner diameter larger than that of other portions at an upper end opening. An outer flange provided on the outer peripheral surface of the upper end portion of the main body of the cylinder liner formed in a cylindrical shape is fitted to the large diameter portion of the cylinder hole to ensure airtightness between the upper surface of the cylinder block and the lower surface of the cylinder head. Liquid tightness
Between the cylinder liner upper end surface and the cylinder head lower surface of an engine provided with a cylinder liner, which is held by a cylinder head gasket that is formed in a flat plate shape and has a bore hole formed at a position aligned with the upper end opening of the cylinder hole. A spacer for closing the formed gap, which is composed of an inner ring made of a thin metal plate with a U-shaped cross section having an opening on the inner peripheral side, and an outer ring made of a thin metal plate having an outer peripheral side opening and enclosing the inner ring. At least two places on the outer edge of
An engine spacer provided with a cylinder liner, wherein a locking tongue is provided as a recess that can be fitted to the inner peripheral edge of a grommet mounted on the inner peripheral edge of a bore hole formed in the cylinder head gasket.