JPH08189414A - Engine cylinder block and method of manufacturing the same - Google Patents

Abstract

(57) [Summary] [Purpose] A cylinder block of a closed deck wet liner engine is manufactured by the die casting method. [Structure] Circular openings 151 and 152 are formed in the upper and lower ends of a hollow insert member 15. A circular hole 171 having substantially the same diameter as the openings 151, 152 is formed inside the insert member 15. The openings 151, 152 and the circular hole 171 are inserted through a cylindrical insert provided in the mold of the cylinder block body, and cast into the cylinder block body 14. At this time, rib 17
Contacts the insert provided in the mold and shares the injection pressure of the die casting applied to the outer peripheral wall of the insert member 15, so that the strength of the insert member 15 is increased. Therefore, the injection pressure of the molten metal can be increased and the pressure resistance of the cylinder block body 14 can be improved. The cylinder liner 16 is inserted into the openings 151, 152 and the circular hole 171 from above the cylinder block body 14.
And the water jacket 18 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die-cast closed-cylinder engine cylinder block and a method of manufacturing the same.

[0002]

2. Description of the Related Art Generally, in a cylinder block of an aluminum alloy engine, a cylinder liner made of a thin wear resistant material is incorporated, and a cylinder bore into which a piston is fitted is formed in the cylinder liner.

In this type of cylinder block, for example,
An open deck type, such as a cylinder block 1 shown in FIG. 16, in which a water jacket 3 formed on an outer peripheral portion of a cylinder liner 2 for circulating cooling water is opened at a cylinder head mounting surface 4, Like the cylinder block 5 shown in FIG. 17, the water jacket 7 formed on the outer peripheral portion of the cylinder liner 6 is closed by the cylinder head mounting surface 8 and the cooling water passage 9 communicating with the water jacket 7 is connected to the cylinder head mounting surface 8. There is a closed deck type with a structure provided with.

The open-deck type cylinder block 1 as shown in FIG. 16 can be easily formed by die-casting when cast from an aluminum alloy or the like, but the cylinder head mounting surface 4 is open. ,
It has the drawbacks of low rigidity and easy generation of vibration and noise.

On the other hand, in the closed-deck type cylinder block as shown in FIG. 17, since the cylinder head mounting surface 8 is closed, the rigidity is high and vibration and noise are less likely to occur. The advantage is that Further, like the cylinder block 10 shown in FIG.
The closed deck wet liner type in which the water jacket 12 is formed on the outer peripheral portion of the cylinder liner 11 is excellent in cooling efficiency because the cooling water in the water jacket 12 directly contacts the cylinder liner 11. In addition,
18, those parts that are the same as those corresponding parts in FIG. 17 are designated by the same reference numerals.

By the way, the closed deck wet liner type cylinder block 10 is difficult to form by the die casting method because the water jacket 12 forms an undercut portion due to its structure, and in general, a collapsible core is used. Although it is molded by the gravity casting method or the low pressure casting method, there is a problem that the core is complicated to manufacture and take out after molding, and the productivity is low.

Therefore, various methods for manufacturing a closed deck wet liner type cylinder block by using a die casting method have been conventionally proposed in order to improve productivity. For example, a method of forming a water jacket using a split type movable core (Japanese Patent Publication No. 2-53623).
Japanese Patent Publication No. 2-53624), a method of forming a water jacket in the same manner as the open deck type and then closing a part of the opening of the cylinder head mounting surface (Japanese Patent Laid-Open No. Hei 1).
No. 100352, Japanese Unexamined Patent Publication No. 1-147145, Japanese Patent Publication No. 2-11735), and a method of casting a cylinder liner having a water jacket in advance (Japanese Unexamined Patent Publication No. 62-
No. 113845, Japanese Utility Model Laid-Open No. 5-78950),
Also, a cylinder liner having a flange portion on the outside of one end is press-fitted into the small diameter portion of the stepped bore formed in the cylinder block, and the large diameter portion of the stepped bore and the side wall and the flange portion of the cylinder liner are used for water. Method of forming a jacket (Japanese Patent Laid-Open No. 60-135650, JP-B-1-10)
No. 427) is proposed.

[0008]

However, the above-mentioned conventional method of manufacturing a cylinder block has the following problems. That is, in the method (1), the structure of the die becomes complicated, the die cost becomes high, and the die life is short. In the above method, the step of closing a part of the opening is complicated, and improvement in productivity cannot be expected so much. In the method (1), the cylinder liner has a complicated shape and is difficult to manufacture. Therefore, improvement in productivity cannot be expected so much. In this method, it is difficult to firmly connect the cylinder block main body and the cylinder liner, and the rigidity of the cylinder block decreases. in this way,
The manufacturing method of the cylinder block shown above to
It cannot be said that any of them have been sufficiently satisfactory.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a member for receiving an external force to an insert member forming a water jacket at the time of manufacture by a die casting method. An object of the present invention is to provide a closed deck wet liner type engine cylinder block that can be easily manufactured, and a method for manufacturing the same.

[0010]

A cylinder block of an engine according to the present invention for solving the above-mentioned problems has circular openings formed in the upper and lower ends of a hollow columnar member, and is formed inside the columnar member. A reinforcing member having a circular hole having substantially the same diameter as the opening and capable of counteracting an external force applied to the columnar member,
A cylinder liner in which the opening and the circular hole can be inserted into a cylindrical portion provided in a mold of a cylinder block body, is cast in an outer peripheral portion of a cylinder bore of the cylinder block body, and can be fitted from above the cylinder block. And the insert member to form a water jacket.

In the present invention, the reinforcing member is preferably a rib integrally formed on the inner wall of the insert member.

Further, according to the method of manufacturing a cylinder block for an engine of the present invention, a circular columnar member having a hollow columnar shape and circular openings at upper and lower ends thereof and having substantially the same diameter as the opening is provided inside the insert member. After loading a backup member having a hole, inserting the opening and the circular hole into a columnar portion provided in the mold of the cylinder block body, and casting and enclosing the same in the outer peripheral portion of the cylinder bore of the cylinder block body, the backup member is removed. A cylinder liner is fitted to the insert member.

Furthermore, as a method of manufacturing an engine cylinder block according to the present invention, inside an insert member having a hollow columnar shape and circular openings formed at the upper and lower ends thereof,
A rib having a circular hole having substantially the same diameter as that of the opening is integrally formed, and the opening and the circular hole are inserted into a cylindrical portion provided in a mold of the cylinder block body, and cast on the outer peripheral portion of the cylinder bore of the cylinder block body. After wrapping, remove the ribs,
A cylinder liner is fitted to the insert member.

[0014]

When an integrally formed rib is provided inside the insert member, when the insert member is die-cast inside the cylinder block main body, an external force such as injection pressure applied to the outer peripheral wall of the insert member is applied to the rib. Since it is shared by the insert member, the insert member does not deform even if the external force is increased. Furthermore, when the cylinder liner is fitted to the insert member, it is sandwiched between the circular openings formed in the upper and lower ends and the circular holes formed in the ribs, so that the insert member and the cylinder liner are joined together. Be strong. By the way, there is a case in which the rib is cast into the cylinder block body and then removed, and the cylinder liner is fitted to the insert member to form an integral water jacket which is not divided inside. Further, when the backup member is loaded inside the insert member, when the insert member is cast into the cylinder block body by die casting, the backup member receives external force such as injection pressure applied to the outer peripheral wall of the insert member. The insert member does not deform even if the external force is increased. Furthermore, since it is not necessary for the insert member itself to receive an external force, the shape of the insert member can be simplified.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the accompanying drawings. In the figure, the same or corresponding parts as those of the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

The cylinder block 13 according to the invention is shown in FIG.
The cylinder block body has a structure as shown in
This is a closed deck wet liner type cylinder block composed of 14, an insert member 15 and a cylinder liner 16. The cylinder block body 14 is made of aluminum die cast. As will be described later, the insert member 15 has a circular opening 1 at the upper and lower ends of the hollow columnar member.
51 and 152 are formed, a rib 17 which is a reinforcing member is integrally formed inside the columnar member, and the rib 17 has a circular hole 171 having substantially the same diameter as the openings 151 and 152. The insert member 15 is cast and enclosed inside the cylinder block body 14, and by fitting the cylinder liner 16 into the openings 151 and 152 and the circular hole 171, the water jacket is inserted.
Forming eighteen. In addition, a cooling water passage 20 communicating with the water jacket 18 is provided on the cylinder head mounting surface 19.

2 to 4, a single view of the insert member 15 will be described. FIG. 2 shows the constituent member 15a of the insert member 15. The constituent member 15a has a shape obtained by halving a hollow columnar member formed by connecting cylindrical members, and is made of aluminum die cast. An insert member 15 having a structure as shown in FIG. 3 and FIG. 4 is obtained by joining two constituent members 15a facing each other.
Becomes The inside of the insert member 15 is hollow, and circular openings 151 and 152 are formed at the upper and lower ends. Also,
A rib 17 having a surface parallel to the upper and lower ends is formed in the hollow interior to divide the hollow interior into a plurality of parts. The rib 17 is formed with a circular hole 171 having substantially the same diameter as the openings 151 and 152, and a communication hole 172 provided between the circular holes.

As described above, since the forming member 15a of the insert member 15 is made of aluminum die-cast, the merit of mass production can be exerted, and the hard and dense chill layer is formed on the casting surface. It is preferable because the waterproof property is improved.

As a method of connecting the forming member 15a,
For example, resistance welding such as projection welding, arc spot welding, TIG welding, MIG welding, welding by friction welding, etc., adhesion using a heat resistant inorganic adhesive such as Aron Ceramic (manufactured by Toagosei Kagaku Kogyo Co., Ltd.), brazing Attach
Alternatively, it is possible to use a method of forming a fitting shape (for example, a pin and a hole, a convex portion and a concave portion, etc.) on the contact surfaces of both, and connecting them by fitting.

The insert member can be integrally manufactured by gravity casting such as shell casting or die casting using a core, or low pressure casting without being divided, and its strength can be increased by heat treatment or the like. .

Next, a method of manufacturing the cylinder block 13 using the die casting method will be described with reference to FIGS. By the way, FIGS. 5 to 9 each show a vertical cross section taken along the line AA in the manufacturing process of the cylinder block 13 of FIG.

First, as shown in FIG. 5, an insert member
The openings 151, 152 of the fifteen and the circular holes 171 of the ribs 17 are inserted into the insert 21a, which is a cylindrical part formed in the mold (cavity mold) 21 of the cylinder block body, and the upper surface of the insert member 15 is inserted into the mold 21. It is brought into contact with the provided substantially columnar projection 21b. Next, as shown in FIG. 6, the mold (core mold) 22 is clamped, and the substantially columnar projection 22a (FIG. 5) is inserted into the insert member 15.
Abut the lower end of the. Then, a hollow region 23 where molten metal does not enter is formed between the insert member 15 and the insert 21a. Here, when the molten metal is injected into the mold, and when it is solidified, the mold is removed, and as shown in FIG. 7, a cylinder block (semi-finished product) 13 'in which the insert member 15 is cast and wrapped around the outer circumference of the cylinder bore of the cylinder block body 14 is obtained. It is formed.
Further, the cylinder block body 14 has a protrusion 21b of the mold 21.
By exposing a part of the upper end of the insert row body 15,
A concave portion 141, which later becomes a cooling water passage, is formed.

Next, as shown in FIG.
A communication hole 24, which will be a passage for cooling water with a cylinder head (not shown), is formed later. Further, the openings 151, 152 and the circular hole 171 are co-machined to obtain the fitting dimension of the fitting portion of the cylinder liner 16. Thereafter, the cylinder liner 16 is press-fitted in the order of the opening 151, the circular hole 171, and the opening 152 to form the water jacket 18 between the insert member 15 and the cylinder liner 16 as shown in FIG.

The water jacket 18 formed as described above is divided into two water jackets 181 and 182 by a rib 17 as shown in FIGS. 1 and 9, and is shown in FIGS. The communication hole 172 allows the two to communicate with each other.

Although not shown, the insert member
The rib 17 integrally formed in the inside of the 15 is not limited to one location, but may be provided in a plurality of locations vertically. Further, the rib 17 can be formed in a spiral shape from the upper end of the insert member 15 toward the lower end.

By the way, the rib 17 formed integrally inside the insert member has a role of sharing the external force such as the injection pressure applied to the outer peripheral wall of the insert member 15. As described above, the cylinder block body 14 is formed by the die casting method, but the die casting product has improved molding conditions and improved quality by increasing the injection pressure. Here, although the insert member 15 ′ having no rib 17 is illustrated in FIG. 10, when the injection pressure of the molten metal becomes high, the insert member 15 ′ may be deformed by losing its external force as shown in the figure. If the injection pressure is reduced in order to avoid this, the molding conditions deteriorate and it becomes impossible to obtain a high quality die cast product. That is, by forming the rib 17 as a reinforcing member on the insert member 15, injection at high pressure becomes possible, and therefore the effect of improving the quality (pressure resistance) of the cylinder block body 14 is great.

As described above, by carrying out the present invention, the following operational effects can be obtained.
First, as shown in FIG. 6, the undercut portion for forming the water jacket 18 is eliminated by fitting the insert 21a provided in the mold into the insert member 15 and casting the insert member. A closed deck wet liner type cylinder block 13 made of an aluminum alloy can be manufactured by using the die casting method. Also,
Since a hard and dense chill layer is formed on the contact surface between the cylinder block body 14 and the insert member 15, the water jacket 18 has improved pressure resistance and waterproofness, and also has improved productivity.

Further, when the insert member 15 is cast into the cylinder block body 14, the rib 17 integrally formed inside the insert member 15 contacts the insert 21a provided in the mold,
Since the external force applied to the outer peripheral wall of the insert member 15 is shared, the strength of the insert member 15 is increased and the injection pressure of the molten metal can be increased. Therefore, the pressure resistance of the cylinder block body 14 is improved.

Further, the cylinder liner 16 forming the water jacket 18 is provided with openings 151, 152 and circular holes 171.
By sandwiching between the insert member 15 and the cylinder liner 16, the cylinder block 13
The rigidity as a whole can be increased. Since the rigidity can be structurally increased in this way, the cylinder liner
It is possible to reduce the meat pressure of the 16 itself and promote weight reduction.

Further, since the water jacket 18 is divided into a plurality of ribs 17 (181, 182) and communicated with each other by the communication holes 172, the flow of cooling water can be made stationary and cooling efficiency is improved. improves.

In the first embodiment described above, the reinforcing member of the type in which the rib 17 is integrally formed inside the insert member 15 is used, but the cylinder block is formed by using the reinforcing member of the following type. You can also A second embodiment of the present invention will be described below with reference to the accompanying drawings. Portions which are the same as or corresponding to those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The insert member 25 and the backup member 26 which is a reinforcing member used in the second embodiment will be described with reference to FIGS. 11 and 12. The insert member 25 is formed by joining two component members 25a made of aluminum die casting, which are formed by connecting cylindrical members to each other to form a hollow columnar member and dividing the member into two halves. The coupling means at this time is the same as in the first embodiment.

The backup member 26 has a shape in which a plurality of cylindrical shapes are connected to each other as shown in FIG.
The diameter of 61 is substantially the same as that of the openings 251 and 252 provided at the upper and lower ends of the insert member 25. Also,
The joining of the two constituent members 25a is performed after filling the backup member 26. At the time when the insert member 25 is formed, the inner peripheral wall 261 of the backup member 26 has an opening.
Exposed from 251 and 252.

The procedure for forming the cylinder block is as follows.
The insert member 25 having the backup member 26 loaded therein as shown in 12 is cast in the cylinder block body 14 in the same manner as the procedure of FIGS. 5 and 6 shown in the first embodiment.
A cylinder block (semi-finished product) 13 'having a backup member 26 inside is formed as shown in FIG. After this, Figure 14
After the backup member is collapsed or melted and removed to obtain the hollow region 27, the cylinder liner 16 is also subjected to the same procedure as shown in FIGS. 8 and 9 of the first embodiment.
The water jacket 28 as shown in FIG.
The cylinder block 13 having the above is formed.

By the way, as a material for forming the backup member 26, a shell core, a molten salt or the like is used. The shell core is made of carboxylic acid-based synthetic resin powder (binder) 3
A core is formed by using sand mixed with ~ 7%.
As mentioned above, the backup member 26 is an insert member.
Since it is loaded inside 25 and cast in the cylinder block body 14, the external force received by the insert member 25 is indirectly received. Therefore, the backup member 26 itself is hard to break, and when it is inserted into the insert 21a formed in the mold (see FIGS. 5 and 6), the backup member 26 is
Even if there is a crack or damage on the insert, insert 21a and insert member
There is no particular problem because it is sealed between 25 and.

Therefore, when the shell core is used as the backup member 26, the disintegration property is emphasized rather than the strength, and the compounding ratio of the binder is set so that it can be disintegrated and removed in the sand baking step at 300 to 350 ° C. or less. can do. If the disintegration property of the backup member 26 is poor, the sand baking process must be performed at a high temperature, and at this time, blisters peculiar to die casting are likely to occur, so caution is required.

When the molten salt is used for the backup member 26, the melting point is not less than the temperature of the mold at the time of molding,
It is preferably 300 to 350 ° C. The backup member 26 does not come into direct contact with the molten metal as described above, but is cooled (although indirectly) via the mold insert 21a. In addition, the melting point of the molten salt is 300 because of the heat capacity.
If it is within the range of ~ 350 ℃, it will not melt during casting. However, if a melting point of 200 ° C. or lower is used, the molten metal is melted by the heat of the melt indirectly transmitted through the insert member 25 and loses its function as a reinforcing member, and the workability is deteriorated, and the mold and molding apparatus are used. Care must be taken as there is a risk of corrosion such as. Further, since the molten salt is water-soluble, it can be easily removed after casting. Specific materials, nitrates _{(Z n, Al, NH 4} , Cd, Gd, K, Ca,
Cr, Tl, Na, M _g system), nitrite (K, Na based), sulfate (Al · k, Al · Tl , Al · Na, NH 4, Co, Tl, there is a Na type) and the like, One of these materials may be used alone, or a plurality of materials may be mixed to adjust the melting point.

As described above, the following operational effects can be obtained by using the second embodiment of the present invention. Inside the insert member 25, a collapsible and removable backup member 26 is loaded, and the insert 21 provided in the mold 21.
Since the backup member 26 fills the hollow area 27 between the insert 21a and the insert member 25, the backup member 26 receives the external force applied to the insert member 25 because the backup member 26 fills the hollow region 27 between the insert member 21a and the insert member 25 by fitting it into a and casting it inside the cylinder block body 14. . Therefore,
The deformation of the insert member 25 is prevented. Further, unlike the first embodiment, it is not necessary to provide reinforcing ribs on the insert member, and the shape of the insert member 25 can be simplified. Therefore, the cost of the insert member 26 can be suppressed. Further, since the deformation does not occur even if the thickness of the insert member 26 is set thin, the insert member 26 can be downsized,
The degree of freedom in designing the shape of the cylinder block 13 as a whole is increased. Further, the inner peripheral wall 261 of the backup member 26 serves as a guide when the insert member 25 is fitted into the insert 21a of the mold 21, and the setting in the mold becomes easy.

By the way, as shown in the first embodiment, in the method of forming the rib 17 which is the reinforcing member inside the insert member 15, after the insert member 15 is cast in the cylinder block body 14, The rib 17 may be removed by machining, and the cylinder liner 16 may be fitted to the insert member to form an integral water jacket 28 which is not divided inside like the second embodiment. In this case, a sufficient cooling capacity can be provided by increasing the flow rate of the cooling water flowing through the water jacket 28. The rib 17 used in this method has
It is not necessary to form the communication hole 172 shown in FIG.

As described above, the present invention has been described by exemplifying the structure of the cylinder block for multiple cylinders (for three cylinders).
It is also possible to use this in a single-cylinder engine, and in this case, the insert member 15 and the like have a single cylindrical shape.

[0041]

Since the present invention is constructed as described above, the following effects can be obtained. When a rib is integrally formed as a reinforcing member inside the insert member, when the insert member is cast in the cylinder block main body, the rib comes into contact with the insert provided in the mold, and the outer wall of the insert member is abutted. Since the external force is shared, the strength of the insert member is increased and the injection pressure of the molten metal can be increased. That is, the pressure resistance of the cylinder block body can be improved by adjusting the molding conditions of the die cast.

Further, when the water jacket is formed, the cylinder liner is sandwiched between the upper and lower end portions of the insert member and the circular holes of the ribs, so that the rigidity of the entire cylinder block can be increased. Therefore, the wall pressure of the cylinder liner itself can be reduced, and the weight reduction can be promoted.

Moreover, since the water jacket is divided into a plurality of parts by the ribs and communicated with each other by the communication holes,
The flow of cooling water can be made to have a steady state, and the cooling efficiency is improved.

When a collapsible and removable backup member is loaded inside the insert member as the reinforcing member, the backup member is provided between the insert member formed in the mold of the cylinder block body and the insert member. The hollow member is filled in and the external force applied to the insert member is received by the backup member, whereby deformation of the insert member can be prevented. Moreover, it is not necessary to provide reinforcing ribs inside the insert member, and the shape of the insert member can be simplified. Therefore, the cost of the insert member can be suppressed. Moreover, since the deformation does not occur even if the thickness of the insert member is set thin, the insert member itself can be downsized, and the degree of freedom in the shape design of the entire cylinder block increases. Furthermore, the inner peripheral wall of the backup member serves as a guide when the insert member is fitted into the insert formed in the mold, which facilitates setting in the mold.

Further, when a water jacket is formed by forming a water jacket by removing the ribs integrally formed inside the insert member after casting in the cylinder block body and fitting the cylinder liner to the insert member. Since an integral water jacket that is not divided by is formed, it is possible to provide a sufficient cooling capacity by increasing the flow rate of the cooling water flowing through the water jacket.

In any of the above-mentioned formats, since the insert member is cast in the cylinder block body by using the die casting method, it is possible to take advantage of low cost in mass production. Also, with the cylinder block body,
Since a hard and dense chill layer is formed on the contact surface with the insert member, the pressure resistance of the water jacket,
Closed deck made of highly waterproof aluminum alloy
Wetliner type cylinder blocks can be manufactured.

[Brief description of drawings]

FIG. 1 is a schematic view of a cylinder block of an engine showing a first embodiment of the present invention.

FIG. 2 is a unitary view showing constituent members of an insert member that is cast in a cylinder block of the engine showing the first embodiment of the present invention.

FIG. 3 is a view showing the structure of an insert member used in the first embodiment of the present invention, and is a vertical sectional view taken along the line BB of FIG.

FIG. 4 is a view showing the structure of an insert member used in the second embodiment of the present invention, and is a cross-sectional view taken along the line CC of FIG.

FIG. 5 is a schematic diagram showing a first stage of a manufacturing process of the cylinder block showing the first embodiment of the present invention.

FIG. 6 is a schematic view showing a second stage of the manufacturing process of the cylinder block.

FIG. 7 is a schematic diagram showing a third stage of the manufacturing process of the cylinder block.

FIG. 8 is a schematic diagram showing a fourth stage of the manufacturing process of the cylinder block.

FIG. 9 is a schematic diagram showing a final stage of a manufacturing process of a cylinder block.

FIG. 10 is a schematic diagram showing a problem when a reinforcing member is not used.

FIG. 11 is a schematic diagram showing a forming member of an insert member and a backup member used in a second embodiment of the present invention.

FIG. 12 is a schematic view showing an insert member used in a second embodiment of the present invention.

FIG. 13 is a schematic diagram showing a third stage of the manufacturing process of the cylinder block showing the second embodiment of the present invention.

FIG. 14 is a schematic diagram showing a fourth step of the manufacturing process of the cylinder block in the second embodiment.

FIG. 15 is a schematic diagram showing the final stage of the manufacturing process of the cylinder block in the second embodiment.

FIG. 16 is a schematic diagram showing a conventional open deck type cylinder block.

FIG. 17 is a schematic view showing a conventional closed deck type cylinder block.

FIG. 18 is a schematic view showing a conventional closed deck wet liner type cylinder block.

[Explanation of symbols]

 13 Cylinder block 14 Cylinder block body 15 Insert member 151 Opening 152 Opening 16 Cylinder liner 17 Rib 171 Circular hole 18 Water jacket 21 Mold 21a Insert 25 Insert member 26 Backup member 28 Water jacket

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number In-house reference number FI Technical indication location F02F 1/16 B (72) Inventor Tadashi Kitano 300 No. 300 Takatsuka-cho, Hamamatsu-shi, Shizuoka Suzuki Stock Company

Claims (4)

[Claims] 1. A hollow columnar member is formed with circular openings at the upper and lower ends thereof, and a circular hole having substantially the same diameter as that of the opening is formed inside the columnar member to prevent an external force applied to the columnar member. An insert member, which is provided with a reinforcing member that can oppose and the opening and the circular hole can be inserted into a columnar portion provided in the mold of the cylinder block body, is cast in the outer peripheral portion of the cylinder bore of the cylinder block body, and the cylinder block A cylinder block for an engine, wherein a water jacket is formed by a cylinder liner that can be fitted from above and the insert member. 2. The cylinder block for an engine according to claim 1, wherein the reinforcing member is a rib integrally formed on an inner wall of the insert member. 3. A backup member having a circular hole having substantially the same diameter as the opening is loaded inside an insert member having a hollow columnar shape and circular openings formed in the upper and lower ends thereof.
The opening and the circular hole are inserted into the cylindrical portion provided in the mold of the cylinder block body, and after being cast and wrapped in the outer peripheral portion of the cylinder bore of the cylinder block body, the backup member is removed, and the cylinder liner is attached to the insert member. A method of manufacturing an engine cylinder block, characterized by being fitted together. 4. A rib having a circular hole having substantially the same diameter as the opening is integrally formed inside the insert member having a hollow columnar shape and circular openings formed at the upper and lower ends thereof. After inserting the circular hole and the cylindrical part provided in the mold of the cylinder block body into the cylinder bore of the cylinder block body and casting it into the outer periphery, remove the ribs and fit the cylinder liner to the insert member. A method of manufacturing a cylinder block of a characteristic engine.