JPS61189863A - Production of engine body - Google Patents

Abstract

PURPOSE:To permit easy casting and to obtain an engine body having high quality without having casting defects by forming the outside walls in a cylinder block part around bores as apertures in the stage of casting integrally a cylinder head part and cylinder block part. CONSTITUTION:The block body 1 which is an intermediate part of the engine body is cast into the state including the cylinder head part 2 and the cylinder block part 3 and is provided internally with the cylinder bores for the four cylinders. The apertures 4 are provided to the right and left outside walls around the bores in the block part 3 of the body 1. Circumferential frames 5 are integrally provided to the edges of the apertures 4 by insert casting. A cover body 6 which consist of a body part 5a and a flange part 5b and is formed by drawing of a ferrous plate (for example, a stainless steel plate) as a blank material is provided to each aperture 4. The cover body 6 is fixed by, for example, laser beam welding to the body 1 in the state of mating the flange part 6b with the frame 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing an engine body, particularly a method of integrally manufacturing a cylinder block portion and a cylinder head portion.

(Prior art) Conventionally, in order to manufacture an engine body, the general method was to form the cylinder block and cylinder head separately by casting, fit them together through a rear gasket, and integrate them with tension and bolts. It is being done.

However, with the above-mentioned split configuration, not only is there dissatisfaction with the rigidity, there is also concern about gas leakage from the gasket part when overheating or high compression is attempted, and furthermore, it takes up space to assemble the tension bolt, and the entire engine There were problems such as having to increase the size of the device.

In view of this background, some attempts have recently been made to integrally form the cylinder block portion and the cylinder head portion by casting, and have achieved some results.

(Problem to be solved by the invention) However, when the cylinder block part and the cylinder head part are integrally formed, the overall structure becomes complicated, so the casting method, especially the core design that constitutes the water jacket part, becomes very difficult. There was also the problem that casting defects such as poor hot water circulation and cavities were likely to occur. There was also the problem that the thickness around the bore was unavoidable, leading to an increase in the overall weight of the engine and a decrease in cooling capacity.

(Means for Solving the Problems) The present invention has been made to solve the above problems.
The feature is that when the cylinder head part and the cylinder block part are integrally cast, the outer wall around the bore in the cylinder block part is made into an opening, and a surrounding frame made of an iron plate is cast into the opening part. Specifically, after the casting, a lid made of a molded iron plate is welded to the peripheral frame to close the opening.

In this case, the cylinder block part and the cylinder head part can be constructed as iron-based castings or aluminum-based castings.

(Function) In manufacturing the engine body with the above configuration, by providing an opening in the outer wall around the bore in the cylinder block, the casting method is simplified and casting becomes easier, and the engine body is free from casting defects. be able to obtain it. Further, since a peripheral frame made of an iron-based plate is cast around the opening in advance, the opening can be easily closed by welding and fixing a lid made of a molded iron-based plate later.

(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings.

FIG. 1 shows a block body which is an intermediate product of an engine body manufactured by the method of the present invention. In the same figure, 1
The block body shown by is integrally cast to include a cylinder head portion 2 and a cylinder block portion 3, and cylinder bores for four cylinders, which will be described later, are provided inside the block body.

The blow 2 main body 1 is provided with an opening 4 on the left and right outer walls around the bore in the cylinder block portion 3, and a peripheral frame 5 is integrally provided at the opening edge of the opening 4.
The peripheral frame 5 is integrally provided by casting, and is made of an iron-based plate, for example, a stainless steel plate.

A lid 6 as shown in FIG. 2 will later be attached to the opening 4 in the block body 1.
1 is drawn from an iron-based plate 1, such as a stainless steel plate, and has a main body portion 8a and a flange portion 8b. The lid 6 is fixed to the block body 1 by, for example, laser beam welding, with its flange portion 8b aligned with the peripheral frame 5.

The main body of this engine is completed in this way, but since the opening 4 is provided when the cylinder head part 2 and cylinder block part 3 are cast together, the casting method is extremely easy and the casting quality is also improved. I come to do it. Further, since the peripheral frame 5 and the lid body 6 cast into the block body 1 are made of iron, welding of them can be performed extremely easily.

The structure of the engine body obtained as described above will now be described in more detail as shown in FIGS. 3 and 4.

That is, the cylinder pore 7 is provided with a rib 8 on its outer periphery.

The ribs 8 are provided to interconnect the plurality of cylinder bores 7, and a cooling water passage 9 is further formed in a portion located between the cylinder bores 7.

The formation of the visible ribs 8 was made possible by the casting method that provided the openings 4 described above, which improved the rigidity of the cylinder block body, and conversely, the cylinder pores 7 This allows for thinner walls. Incidentally, in the case of a cylinder block made of conventional iron castings,
The wall thickness of the cylinder bore portion is approximately 4 to 5 inches, but with the above structure, this can be reduced to approximately 3 inches. By making the engine thinner, it is possible to not only reduce the weight of the engine as a whole, but also improve its cooling capacity.

Note that the block body 1 is put into practical use with the inner surface of the cylinder pore 7 polished and finished, but an escape groove 10 is provided at the upper end of the cylinder pore 7, thereby making it possible to cope with the aforementioned polishing. .

In addition, the lid attached to the opening 4 of the block body 1 is made of a so-called fiber-reinforced laminate, in which an iron plate 11 is sandwiched between resins 12a and 12b, instead of the above embodiment, for example, as shown in FIG. It can be formed from the body, and in this case, vibration damping properties can be further improved.

(Effects of the Invention) As described above in detail, the present invention makes the outer wall of the cylinder block part around the bore an opening when integrally casting the cylinder head part and the cylinder block part, so that the casting method is improved. The simplification made casting easier, and the result was the ability to manufacture high-quality engine bodies without casting defects.

In addition, since the opening is cast with a surrounding frame made of iron-based plates, it is possible to easily attach the lid body made of a molded iron-based plate by welding.
The effect of reducing assembly man-hours was achieved.

Furthermore, the simplification of the casting method allows the cylinder bore to be made thinner, resulting in the reduction in weight of the engine as a whole and improvement in cooling capacity. In addition, to the cylinder -2
Needless to say, there is a ripple effect due to the improved natural vibration characteristics due to the integration of the cylinder block and the cylinder block.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a block body which is an intermediate product of the engine body manufactured by the method of the present invention, Figure 2 is a perspective view of a lid attached to the aforementioned block body, and Figure 3 is the internal structure of the engine body. 4 is a perspective view showing a part of the structure around the bore, and FIG. 5 is a sectional view showing another embodiment of the lid. 2... Cylinder head section 3... Cylinder block section 4... Opening section 5... Surrounding frame 6... Lid body Fig. 1 Fig. 3

Claims (1)

[Claims] (1) When integrally casting the cylinder head part and the cylinder block part, the outer wall around the bore in the cylinder block part is formed into an opening, and a peripheral frame made of an iron plate is cast into the opening, and the casting A method of manufacturing an engine body, wherein the opening is closed by welding a lid made of a molded iron plate to the peripheral frame.