JPH09242598A - Cylinder block insert member and method for manufacturing cylinder block - Google Patents

Abstract

(57) Abstract: In a closed deck wet liner type cylinder block in which an insert member is cast-in, manufacturing of the insert member is facilitated. SOLUTION: A cylinder block body 2 has a flange portion.
The insert member 13 having 14 and 15 is cast and wrapped. Closed deck wet liner type cylinder block 12 by press fitting the cylinder liner 8 into the bore 7 and the flanges 14 and 15.
Get. By fitting a part of the mold into the flange portions 14 and 15 and disposing the insert member 13 in the cavity, the undercut portion for forming the water jacket 9 is eliminated and die casting becomes possible. . Since the insert member 13 has a structure in which the cap member 17 having the flange portion 15 is fitted to the main body member 16 having the flange portion 14, it can be easily press-molded. Insert member 13
By loading a collapsible reinforcing member during casting,
It is possible to prevent deformation due to casting pressure and reduce the thickness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insert member for a cylinder / cylinder block of a closed deck wet liner type engine and a method of manufacturing a cylinder block using the same.

[0002]

2. Description of the Related Art Generally, a cylinder liner made of a thin wear-resistant material is incorporated in a cylinder block of an aluminum alloy engine, and a cylinder bore in which a piston is fitted is formed in the cylinder liner. In a cylinder block of this type, rigidity is increased by adopting a so-called closed deck / wet liner type structure in which a cylinder head mounting surface is closed and a water jacket is formed on an outer peripheral portion of the cylinder liner. As a result, vibration and noise are less likely to be generated, so that the thickness and weight can be reduced. Further, since the cooling water in the water jacket is in direct contact with the cylinder liner, the cooling efficiency can be improved.

However, in the closed deck / wet liner type cylinder block as described above, the water jacket forms an undercut portion at the time of casting, so that it is difficult to form the cylinder block by die casting.
There was a problem of low productivity.

Therefore, the applicant of the present invention has proposed a cylinder block 1 as shown in FIG. 17 in order to manufacture a closed deck wet liner type cylinder block by using the die casting method (Japanese Patent Application No. 6-338143). Etc.).

In the cylinder block 1 shown in FIG. 17, a cylindrical insert member 6 having flanges 4 and 5 inside both ends is cast and wrapped around the outer periphery of the cylinder bore 3 of the cylinder block body 2. A cylindrical cylinder liner 8 is press-fitted into the bore 7 of the cylinder block body 2 and the flange portions 4 and 5 of the insert member 6 to form the cylinder bore 3. Then, the water jacket 9 that surrounds the circumference of the cylinder bore 3 by the side wall of the insert member 6 and the flange portions 4, 5 and the side wall of the cylinder liner 8.
Are formed. A plurality of cooling water passages 11 are formed in a cylinder head mounting surface 10 (hereinafter, referred to as a deck surface 10) of the cylinder block main body 2 so as to penetrate the flange portion 4 of the insert member 8 and communicate with the water jacket 9.

With this construction, the insert member 6 is placed in the cavity of the mold so that a part of the mold is inserted into and fitted into the flanges 4 and 5 during casting. Therefore, it is possible to mold the cylinder block body 2 in which the insert member 6 is cast-in by using the die casting method. Then, the closed deck wet liner type cylinder block 1 can be manufactured by press-fitting the cylinder liner 8 into the bore 7 of the cylinder block body 2 and the flange portions 4 and 5 of the insert member 6.

[0007]

Since the insert member 6 used in the cylinder block 1 shown in FIG. 17 is a tubular member having flange portions 4 and 5 inside both end portions,
Difficult to integrally mold. Further, when such a cylinder block is manufactured by the die casting method, the insert member is subjected to a casting pressure, and therefore the rigidity of the insert member needs to be sufficiently high in order to prevent deformation due to this pressure. Therefore, if the insert member is made thicker or the reinforcing ribs are provided, the cylinder block becomes larger and the manufacturing cost of the insert member becomes higher.

The present invention has been made in view of the above points, and an object thereof is to reduce the thickness of an insert member, facilitate its manufacture, and prevent excessive deformation of the insert member due to casting pressure. And

[0009]

In order to solve the above problems, an insert member for a cylinder block according to a first aspect of the present invention is a cylinder having an outer peripheral portion of a cylinder bore of a cylinder block body and flange portions inside both end portions. An insert member for a cylinder block of an engine, in which a cylindrical insert member is cast-in, and a cylinder liner is inserted into the insert member to be fitted to the flange portion, at one end of a tubular main body member, It is characterized in that a cap member having a flange portion is fitted inside the portion.

With this structure, by fitting the cap member to the main body member, a cylindrical insert member having flange portions inside both end portions is obtained.

The insert member for a cylinder block according to claim 2 is characterized in that, in addition to the constitution of claim 1, the main body member and the cap member are press-molded products.

With this structure, the main body member and the cap member can be easily formed by pressing.

According to a third aspect of the present invention, there is provided a method for manufacturing a cylinder block, wherein a collapsible or fusible reinforcing member is loaded in a solidified state between both flange portions of the insert member according to the first or second aspect. The insert member is arranged in the cavity of the mold so that a part of the mold is inserted into and fitted into the flange portion and the reinforcing member, the molten metal is cast into the cavity, and the insert is provided on the outer peripheral portion of the cylinder bore. After die-casting the cylinder block main body so as to cast-in the member, after the reinforcing member is collapsed or melted and removed from the insert member, the cylinder liner is inserted into the insert member and fitted to the both flange portions. It is characterized by having done.

With this structure, the reinforcing member can prevent the insert member from being deformed due to the casting pressure, and the closed deck wet liner type cylinder block can be manufactured.

According to a fourth aspect of the present invention, in addition to the structure of the third aspect, the cylinder block manufacturing method forms a space between the insert member and the reinforcing member, and causes the insert member to become the reinforcing member by casting pressure. The feature is that it is deformed along.

With this structure, the insert member is shaped along the outer shape of the reinforcing member by the casting pressure, and
The reinforcing member prevents excessive deformation of the insert member.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. The cylinder block according to the present embodiment is generally the same as the cylinder block 1 shown in FIG. 17 except that the insert member is different. Therefore, the same parts as those shown in FIG. Will be described.

As shown in FIGS. 1 and 2, the cylinder block 12 according to the present embodiment is a closed deck wet liner type cylinder block for an in-line three-cylinder engine, and the cylinder block main body 2 made of an aluminum alloy is used. , Three cylinder bores 3 for fitting pistons (not shown) are arranged in series.

The outer peripheral portion of the three cylinder bores 3 is shown in FIG.
Further, as shown in FIG. 4, a cylindrical insert member 13 in which three cylindrical members are arranged in series and their side surface portions are connected to each other and the insides thereof are communicated with each other is cast-in. Flange portions 14 and 15 are formed inside both ends of the insert member 13, respectively. Flange portion of the bore 7 and the insert member 13 formed in the cylinder block body 2
A cylindrical cylinder liner 8 is press-fitted into 14 and 15 to form a cylinder bore 3. And insert member
The side wall of 13 and the flange portions 14 and 15 and the side wall of the cylinder liner 8 form a water jacket 9 surrounding the cylinder bore 3. On the deck surface 10 of the cylinder block body 2, the flange portion 15 of the insert member 13
A plurality of cooling water passages 11 that penetrates through and communicates with the water jacket 9 are opened.

The insert member 13 comprises a cylindrical main body member 16 having three cylindrical members arranged in series and having their side surfaces joined to each other so that the insides thereof communicate with each other and a flange portion 14 is formed inside one end thereof. It is configured by fitting a cap member 17 formed in a tubular shape similar to the main body member 16 and having a flange portion 15 inside the one end portion on the outside of the other end portion. The body member 16 and the cap member 17 of the insert member 13 may be thin and can be easily formed by pressing an aluminum alloy plate or an iron plate having a plate thickness of about 0.2 to 2.0 mm.

Next, a method of manufacturing the cylinder block 12 using the die casting method will be described with reference to FIGS.

As shown in FIG. 5, in the annular space between the flange portions 14 and 15 in the insert member 13, that is, in the space forming the water jacket 9, in the state where the collapsible or meltable reinforcing member 18 is solidified. Load it. As shown in FIG. 6, the reinforcing member 18 includes both flanges 14 and 15 of the insert member 13.
In accordance with the shape of the space between them, three cylindrical members are arranged in series and preformed into a shape in which the side surfaces are joined, and then inserted into the main body member 16, and then the main body member 16 is capped with a cap member 17.
Can be loaded into the insert member 13 by fitting. Alternatively, a cylindrical member (not shown) is inserted into both flange portions 14 and 15 of the insert member 13 to define a closed annular space between both flange portions 14 and 15 in the insert member 13, and this space is formed. After being filled with a fluid reinforcing material, it can be solidified and then loaded into the insert member 13.

The reinforcing member 18 is a member that can be removed from the insert member 13 by collapsing or melting what is loaded in the insert member 13 in a solidified state.
Examples of the material include resin coated sand (hereinafter, referred to as R, which is generally used for forming a shell core).
SC), silica sand as used for organic binder self-hardening mold material, mixture of binder and curing agent, or molten salt of nitrate, nitrite, sulfate or the like.

Then, the insert member 13 loaded with the reinforcing member 18 is set in the die casting mold 19 as shown in FIGS. 7 and 8. First, as shown in FIG.
The core metal 21 (a part of the mold) for forming the bore 19 is inserted into the cylinder block body 14 provided on the insert member.
Inserted into 13 and fitted to flanges 14 and 15 for cooling water passage
A guide pin 22 forming a part of 11 is brought into contact with the flange portion 15. At this time, the reinforcing member 18 is placed between the flange portions 14 and 15.
Since the insert member 13 has a cylindrical shape with a substantially uniform wall pressure, the core metal 21 can be easily inserted. Next, as shown in FIG. 8, the movable die 20 and the fixed die
22 and the mold are clamped to form the cavity C, and the guide pin 24 provided on the fixed mold 23 is brought into contact with the flange portion 14 to position the insert member 13 in the cavity C. Thereby, between the insert member 13 and the core metal 21,
A closed space S is formed in which the reinforcing member 18 is loaded.

After that, the molten aluminum alloy is cast into the cavity C, the cylinder block body 2 is cast, and the insert member 13 is cast up, whereby the insert member 13 is integrated with the cylinder block body 14. Since the molten metal is not injected into the space S, the water jacket 9
Space is secured. Here, the high temperature molten metal comes into contact with the insert member 13, but in the die casting method, since the molten metal is solidified relatively quickly, softening and melting of the insert member 13 are less likely to occur. Insert member made of aluminum alloy
13 can be used.

The movable die 20 and the fixed die 23 are opened, the insert member 13 is extracted from the core metal 21, and the cast product is released from the mold, as shown in FIG.
The cylinder block main body 2 in which the insert member 13 shown in FIG. Then, the reinforcing member 18 is formed by heat treatment or the like.
Is collapsed or melted and removed from the insert member 13 to secure a space to be the water jacket 9. Here, the reinforcing member 18 is filled in the annular space S sealed by the cored bar 21 of the movable die 20 at the time of casting, and can withstand a sufficiently high pressure. Considering the disintegration property or the melting property, it is preferable to consider it.

Next, by machining, the bore 7 of the cylinder block body 2 and the flange portion 1 of the insert member 13 are machined.
4 and 15 are co-machined to obtain a fitting dimension of the press-fitting portion of the cylinder liner 8 and a cooling water passage 11 is bored in the deck surface 10.
After that, as shown in FIG. 2, by inserting the cylinder liner 8 into the bore 7 of the cylinder block body 2 and the flange portions 14 and 15 of the insert member 13, the insert member is inserted.
The water jacket 9 is formed between the cylinder liner 8 and the cylinder liner 8 so that a closed deck wet liner type cylinder block 12 can be obtained.

As described above, the core metal 21 which is a part of the mold is fitted to the insert member 13 in which the reinforcing member 18 is loaded, and the insert member 13 is cast-in to form the water jacket 9. Since the undercut portion is eliminated, the closed deck wet liner type cylinder block 12 made of an aluminum alloy can be manufactured by using the die casting method. Further, since a hard and dense chill layer is formed on the casting surface of the cylinder block body 2 by die casting, the pressure resistance of the water jacket 9 is improved. Further, since the reinforcing member 18 prevents the insert member 13 from being deformed due to casting pressure, the insert member 13 can be made thin, and high-pressure casting is possible, so that the dense and high-quality cylinder block 12 can be obtained. It can be molded.

Since the reinforcing member 18 loaded in the insert member 13 is only indirectly subjected to compressive stress via the insert member 13 during casting, cracks and breakage have occurred at the time of being set in the mold. However, there is no problem in strength. Therefore, when RSC is used as the material of the insert member 13, the collapsibility is emphasized rather than the strength, and
It is advisable to set the compounding ratio of the binder so that it can be disintegrated and removed in the sand baking process at about 0 ° C. In this case, the reinforcing member 18
If the disintegration property is poor, the sand-baking process must be performed at a high temperature, and at this time, blister peculiar to die casting is likely to occur, so be careful.

When a molten salt is used as the material of the reinforcing member 18, the melting point is not less than the mold temperature at the time of casting,
It is preferably 300 to 350 ° C. Reinforcement member 18
Does not come into direct contact with the molten metal, and the core metal 21
The melting point is 300 because of the heat capacity.
If it is within the range of ~ 350 ℃, it will not melt during casting.
However, if a material having a melting point of 200 ° C. or lower is used, it is melted by the heat of the molten metal that is indirectly transmitted through the insert member 25, and is softened to lose its function as a reinforcing member, and the workability is deteriorated. Care must be taken as it may lead to corrosion of molds, molding equipment and the like. Further, since the molten salt is water-soluble, it can be easily removed after casting. Specific examples of the molten salt include nitrates (Zn, Al, NH ₄ , Cd, Gd, K,
Ca, Cr, Tl, Na, Mg type), nitrite (K, Na type), sulfate (Al ・ K, Al ・ Tl, Al ・ Na, NH ₄ , Co, T)
l, Na type) and the like, and these may be used alone, or a plurality of types may be combined to adjust the melting point.

Next, the first to third modified examples of the insert member that is cast in the cylinder block body 2 will be described with reference to FIG.
Through FIG. 16 will be described. In the following description, like parts of the insert member 13 will be designated by like reference numerals and only different parts will be described in detail.

As shown in FIGS. 10 and 11, the insert member 25 according to the first modification has a cylindrical shape in which three cylindrical members are arranged in series and their respective side surfaces are connected to each other so that the insides thereof communicate with each other. It is configured by fitting cap members 27 and 28, which are formed in the same tubular shape as the main body member 26 and have the flange portions 14 and 15 inside the one end portions, on the outer sides of both ends of the main body member 26, respectively. . The body member 26 and the cap members 27, 28 of the insert member 25 may be thin and can be easily formed by pressing an aluminum alloy plate or an iron plate having a plate thickness of about 0.2 to 2.0 mm. The insert member 25 configured as described above can be cast in the cylinder block body 2 in the same manner as the case of the insert member 13 and can be used for manufacturing the cylinder block 12.

As shown in FIGS. 12 and 13, the insert member 29 according to the second modified example is a tubular shape having an oval cross section and a bottom portion at one end, and the insert member 29 has a bottom portion formed along the longitudinal direction.
Body member with two holes and flange 14 formed inside
A cap member that is formed in a cylindrical shape similar to the main body member 30 on the outer side of the other end portion of 30 and has a flange portion 15 on the inner side of the one end portion.
It is configured by fitting 31 together. The body member 30 and the cap member 31 of the insert member 29 may be thin and can be easily formed by pressing an aluminum alloy plate or an iron plate having a plate thickness of about 0.2 to 2.0 mm.

When the insert member 29 is cast in the cylinder block body 2, as shown in FIG. 14, after the preformed reinforcing member 18 (see FIG. 6) is inserted into the body member 30, the body member 30 is capped. By fitting the member 31,
The reinforcing member 18 is loaded in the insert member 29. At this time, a space A is formed between the side wall of the main body member 30 and the reinforcing member 18. The insert member 29 loaded with the reinforcing member 18 is set in the die casting mold 19 and cast in the cylinder block body 2 in the same manner as in the case of the insert member 13. In this case, a space A is formed between the insert member 29 and the reinforcing member 18.
Since, since the side wall of the insert member 29 softened by the temperature of the molten metal is deformed along the outer surface of the reinforcing member 18 by the casting pressure during casting, the insert member 29 is similar to the insert member 13 described above. It is shaped into a proper shape and is cast in the cylinder block body 2. Then, the cylinder block 12 can be manufactured in the same manner as when the insert member 13 is used. The insert member 29 of the second modification is the insert members 13 and 25 described above.
On the other hand, since the shape is simple, the productivity can be improved and the manufacturing cost can be reduced.

In this case, stress other than compressive stress also acts on the reinforcing member 18 during the deformation process of the insert member 29. Therefore, in order to reliably shape the insert member 29, the reinforcing member 18 is It is necessary to select a material that can obtain sufficient strength in addition to disintegration.

As shown in FIGS. 15 and 16, the third
The insert member 32 according to the modified example has the same shape as the cap member 31 of the second modified example having the flange portions 14 and 15 on the outer sides of both ends of the cylindrical main body member 33 having an oval cross section. It is configured by fitting the cap members 34 and 35 of. The body member 33 and the cap members 34 and 35 of the insert member 32 may be thin and have a plate thickness of 0.2 to 2.
It can be easily formed by pressing an aluminum alloy plate or an iron plate of about 0 mm. The insert member 32 configured as described above can be cast in the cylinder block body 2 similarly to the case of the insert member 29 of the second modified example, and can be used for manufacturing the cylinder block 12. Since the insert member 32 of the third modified example also has a simpler shape than the insert members 13 and 25, it is possible to improve productivity and reduce manufacturing cost.

Although the cylinder block for the in-line three-cylinder engine is described as an example in the above-described embodiment and modification, the present invention is not limited to this, and a multi-cylinder or single-cylinder engine of another type. It can be similarly applied to a cylinder block for.

[0038]

As described above in detail, the insert member for a cylinder block according to claim 1 has a structure in which the cap member is fitted to the main body member, so that the cylindrical insert having the flange portions inside both end portions. The member can be easily manufactured, and a closed deck wet liner type cylinder block can be manufactured by using the die casting method by casting the member in the outer peripheral portion of the cylinder bore.

Further, in the insert member for a cylinder block according to the second aspect, since the main body member and the cap member are pressed products, the productivity can be improved and the manufacturing cost can be reduced.

According to the method of manufacturing a cylinder block of claim 3, the undercut portion of the cylinder block main body can be eliminated by fitting a part of the die to the insert member, and the insert member can be removed. It is possible to die cast the cast-in cylinder block body. Then, by fitting the cylinder liner to the flange of the insert member,
Wetliner type cylinder blocks can be manufactured. As a result, a closed-deck wet liner type cylinder block can be manufactured by using the die casting method, so that productivity can be improved and manufacturing cost can be reduced. Further, since the reinforcing member prevents the insert member from being deformed during casting, the insert member can be made thin, and high-pressure casting becomes possible to form a dense and high-quality cylinder block. it can.

Further, according to the method of manufacturing a cylinder block of claim 4, since the insert member is shaped along the outer shape of the reinforcing member by the casting pressure, the shape of the insert member can be simplified and the productivity can be improved. Can be improved and the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a cylinder block according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of the cylinder block of FIG.

FIG. 3 is a perspective view of an insert member that is cast in the cylinder block of FIG. 1.

FIG. 4 is an exploded perspective view of the insert member of FIG.

5 is a perspective view showing a state in which a reinforcing member is loaded in the insert member of FIG. 3 with a part thereof broken away.

FIG. 6 is a perspective view of a reinforcing member loaded in the insert member of FIG.

7 is a schematic view showing an open state of a die casting mold for casting the cylinder block body of FIG. 1. FIG.

8 is a schematic view showing a closed state of the die casting mold of FIG. 7. FIG.

9 is a vertical cross-sectional view of a cylinder block body cast by the die casting mold shown in FIGS. 7 and 8. FIG.

FIG. 10 is a perspective view of a first modified example of the insert member that is cast in the cylinder block of FIG. 1.

11 is an exploded perspective view of the insert member of FIG.

FIG. 12 is a perspective view of a second modified example of the insert member that is cast in the cylinder block of FIG. 1.

FIG. 13 is an exploded perspective view of the insert member of FIG.

14 is an exploded perspective view showing a state where a reinforcing member is loaded on the main body member of the insert member of FIG.

FIG. 15 is a perspective view of a third modified example of the insert member that is cast in the cylinder block of FIG. 1.

16 is an exploded perspective view of the insert member of FIG.

FIG. 17 is a partially cutaway view of a closed deck wet liner type cylinder block including an insert member cast therein.

[Explanation of symbols]

 2 Cylinder block body 3 Cylinder bore 8 Cylinder liner 12 Cylinder block 13,29,32 Insert member 14,15 Flange portion 16,26,30,33 Body member 17,27,28,31,34,35 Cap member 18 Reinforcing member 19 Die casting mold (mold) 21 Core metal (part of the mold) C Cavity A Space

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location F02F 1/16 F02F 1/16 B

Claims (4)

[Claims] 1. A cylindrical insert member having flange portions inside both end portions is cast on the outer peripheral portion of a cylinder bore of a cylinder block body, and a cylinder liner is inserted into the insert member and fitted into the flange portion. An insert member for a cylinder block of an engine, wherein the insert member is configured by fitting a cap member having a flange portion inside one end portion to an end portion of a tubular main body member. Cylinder block insert member characterized by. 2. The insert member for a cylinder block according to claim 1, wherein the main body member and the cap member are press-molded products. 3. A collapsible or meltable reinforcing member is loaded in a solidified state between both flange portions of the insert member according to claim 1 or 2, and a part of a mold is fitted to the flange portion and the reinforcing member. After the insert member is placed in the cavity of the mold so as to be inserted and fitted, the molten metal is cast into the cavity, and the cylinder block body is die-cast so as to wrap the insert member around the outer periphery of the cylinder bore. A method of manufacturing a cylinder block, characterized in that the reinforcing member is collapsed or melted and removed from the insert member, and then a cylinder liner is inserted through the insert member to be fitted into the both flange portions. 4. The cylinder block according to claim 3, wherein a space is formed between the insert member and the reinforcing member, and the insert member is deformed along the reinforcing member by a casting pressure. Manufacturing method.