JPS6277149A - Production of cylinder block - Google Patents

Abstract

PURPOSE:To improve castability and to stabilize quality by joining both end sections in the stroke direction of adjacent cylinder liners by joining members and successively providing the cylinder liners at prescribed intervals provided therebetween thereby assuring the positional accuracy of the cylinder liners. CONSTITUTION:Both end sections in the stroke direction of the respective adjacent cylinder liners 2-1-2-4 are joined respectively by joining members 4-1-4-3 and joining members 6-1-6-3. The cylinder liners 2-1-2-4 are thereby successively provided at the prescribed intervals A provided therebetween. The cylinder liners 2-1 and 2-4 at both ends in the direction where the liners are successively provided are supported by supports 10 and are held in the prescribed position to be cast, then casting is executed, by which the cylinder block is cast. The cylinder block cast in the above-mentioned manner is prevented from overturn without the need for means for preventing the displacement from the prescribed positions of the liners 2-1-2-4 and the positional accuracy is assured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to a method of manufacturing a cylinder block, and in particular to a method of manufacturing a cylinder block, which improves castability and improves quality by ensuring positional accuracy of a cylinder liner that is cast into a cylinder block. The present invention relates to a method for manufacturing a cylinder block that is stable.

[Prior Art] Conventionally, there has been an internal combustion engine in which cylinders are arranged in series in a cylinder block as disclosed in Japanese Patent Application Laid-Open No. 59-85466, and in particular, in Japanese Patent Application Laid-Open No. 59-194061.
As disclosed in the above publication, there is a cylinder liner in which cylinders are arranged in series and a cylinder liner integrally formed from different materials is cast into a cylinder block. In such a cylinder block, especially when manufacturing a cylinder block 12 in which independent cylinder liners 2-1 to 2-4 made of different materials are manufactured as shown in FIGS. 5 and 6, each cylinder liner is 2-1 to 2-4 are each supported by a support 10, thereby holding each cylinder liner 2-1 to 2-4 in a predetermined position to be cast, and the cylinder block 12 is cast. This casting forms the water jacket 14 on the cylinder block 12. After casting, a deck surface 16 is formed on the cylinder head side. In this way, cylinder liners that are cast independently have good manufacturability and workability because they can be manufactured individually, and they are also more resistant to heat during engine operation, such as cylinder liners that are cast with the cylinder integrally formed. It is possible to avoid the inconvenience of abnormal deformation caused by mutual influence due to distortion.

[Problems to be Solved by the Invention] However, when the cylinder block 12 is cast, thermal deformation of each support 10 of the cylinder liners 2-1 to 2-4 and fitting with the cylinder liners 2-1 to 2-4 occur. Due to tolerances, etc., each cylinder liner 2-1 to 2-4 may be displaced from its predetermined position, resulting in loss of relative positional accuracy, and so-called smearing may occur in each cylinder liner 2-1 to 2-4 after casting. be.

As a result, the wall thickness of each cylinder liner 2-1 to 2-4 became uneven due to grinding of the bore surface 16 after casting, resulting in a problem of unstable quality. For this reason, it is desirable to take measures to prevent the cylinder liner from displacing from a predetermined position during casting, but on the other hand, an increase in the number of operations causes a problem in which castability deteriorates, so an improvement was desired.

[Object of the Invention] Therefore, an object of the present invention is to ensure positional accuracy by preventing displacement of the cylinder liner cast into the cylinder block from a predetermined position, thereby improving castability of the cylinder block and stabilizing quality. The object of the present invention is to realize a method for manufacturing a cylinder block that can achieve the above-mentioned effects and also prevent abnormal deformation due to thermal distortion.

[Means for Solving the Problems] In order to achieve this object, the present invention connects both end portions of adjacent cylinder liners in the stroke direction with a joining member, so that the cylinder liners are connected at a required interval. Next, by supporting a part of this cylinder liner, a cylinder block is cast by holding the continuous cylinder liner in a predetermined position to be cast, and then the cylinder liner cast into this cylinder block is cast. A deck surface is formed by removing the joining member located on the cylinder head side.

[Operation] According to the method of the present invention, when casting cylinder liners into a cylinder block, first, both end portions of adjacent cylinder liners in the stroke direction are joined using joining members, and then some of the cylinder liners are supported. Then, the cylinder liners are held in series at the required intervals at predetermined positions to be cast, and then the cylinder block is cast. After that,
The joining member located on the cylinder head side of the cylinder liner cast into the cylinder liner is removed, a deck surface is formed, and a cylinder block is manufactured.

[Example] Next, an example of the present invention will be described in detail based on the drawings. 1 to 4 show embodiments of this invention, and 2-
1 to 2-4 are cylinder liners, 4-1 to 4-3, 6-1
6-3 are joint members, 8-1 to 8-4 are bore surfaces, 1o is a support, 12 is a cylinder block, 14 is a water jacket, and 16 is a deck surface.

In manufacturing, first, as shown in FIGS. 1 and 2, both end portions of the adjacent cylinder liners 2-1 to 2-4 in the stroke direction are connected to the joint members 4-1 to 4-3 and the joint member 6-1, respectively. ~Join in 6-3.

Thereby, the cylinder liners 2-1 to 2-4 are arranged one after another with the required interval A provided therebetween.

In this way, the joining members 4-1 to 4-3, 6-1 to 6-3
By providing the required interval A, each cylinder line-1-2-1
Since the cylinder liners 2-1 to 2-4 are arranged in series, there is no need to support all the cylinder liners 2-1 to 2-4 with respective supports during casting (in addition, it is not necessary to support some of the cylinder liners). Possibly all cylinder liners 2-1~2
-4 can be held in place for casting. Further, it is possible to prevent so-called sagging from occurring on each cylinder liner 2-1 to 2-4 during casting, and to ensure positional accuracy. Furthermore, since the cylinder liners can be manufactured individually, productivity and processability are good.

Cylinder liners 2-1 arranged in series with this required interval A
- Some of the cylinder liners 2-4, for example, cylinder liner 2-1 and cylinder liner 2-4 at both ends in the connecting direction as shown in FIG. do.

The cylinder liners 2-1 to 2-4 held in predetermined positions are cast, and the cylinder block 12 is cast as shown in FIGS. 3 and 4. At this time, a walk jacket 14 is formed on the cylinder block 12.

The Nlindaburo Tsuku 12 cast in this way is
In particular, positional accuracy can be ensured by preventing staining without requiring any means to prevent displacement of each cylinder liner 2-1 to 2-4 from a predetermined position, thereby stabilizing quality and improving castability. can do.

The cast cylinder block 12 is attached to the joining member 4-, which is located on the cylinder head side (the upper side in FIG. 4) of the cast cylinder liners 2-1 to 2-4, as shown by the dashed line in FIG. Delete 1 to 4-3. This results in
In addition to forming the deck surface 16, the bore surface 8-1
The cylinder block 12 is manufactured by grinding ~8-4.

By removing the joining members 4-1 to 4-3, the cylinder head side of each cylinder liner 2-1 to 2-4 becomes independent, thereby eliminating mutual influence due to thermal distortion during engine operation. Abnormal deformation can be prevented.

[Effects of the Invention] As described above, according to the present invention, when manufacturing a cylinder block, the cylinder liners to be cast are arranged consecutively at the required intervals, so that all the cylinder liners are supported by supports etc. during casting. There is no need for support, and by supporting some of the cylinder liners, all the cylinder liners can be held in place for casting. Thereby, displacement of the cylinder liner from a predetermined position can be prevented and positional accuracy can be ensured, so that castability can be improved and quality can be stabilized. In addition, since the cylinder liner to be cast can be manufactured individually, manufacturability and workability are good, and furthermore,
Since the joining member located on the cylinder head side of the cast cylinder liner is removed, each cylinder head side of the cylinder liner becomes independent, eliminating mutual influence due to thermal distortion during engine operation and preventing abnormal deformation. can be prevented.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, FIGS. 1 and 2 are a plan view and a front view of cylinder liners arranged in series, and FIGS.
Figure 4 is a plan view and a sectional view of the cast cylinder block. 5 and 6 are a plan view and a sectional view of a conventional cylinder block. In the figure, 2-1 to 2-4 are cylinder liners, 4-1
~4-3・6-1~6-3 are joining members, 8-1~8-4
is the bore surface, 10 is the support, 12 is the cylinder block, 1
4 is a water jacket, and 16 is a deck surface.

Claims (1)

[Claims] The cylinder liners are connected at a required interval by joining both end portions in the stroke direction of adjacent cylinder liners with respective joining members, and then, by supporting a part of the cylinder liners, the cylinder liners are placed at a predetermined position to be cast. A cylinder block is cast while holding the continuous cylinder liners, and then the joining member located on the cylinder head side of the cylinder liner cast into the cylinder block is removed to form a deck surface. A method for manufacturing a cylinder block.