JPS63101067A - Production of cylinder block - Google Patents

Abstract

PURPOSE:To form a water-jacket part with using any cores and to improve the productivity by casting in the top part of water-jacket by a top-deck after casting an open-deck type cylinder block. CONSTITUTION:The open-deck type cylinder block SO0 is molded. Next, the molten metal 14 is poured in the mold TD at the prescribed quantity, and promptly the open-deck type cylinder block S0 is made to over-turned condition and the top part thereof is set at the prescribed position in the mold TD. Then, gas generated in the closed water jacket part 6 is exhausted through a gas exhaust hole 13. After that, the molten metal 14 is cooled and solidified, and then, by taking out the cylinder block, the casting of closed deck-type cylinder block SC is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing a closed deck type cylinder block formed by casting and having water holes at the top of a water jacket.

(Prior Art) Conventionally, there is a method of manufacturing a closed deck type cylinder block, as shown in Fig. 4.5, for example.The main shape of this is an upper mold 1. a lower mold 2. The water jacket, which is an internal shape that cannot be formed using the side mold 3, is formed using the core 4, and after constructing the mold according to the steps shown in the manufacturing process block diagram, By filling the cavity 5 with molten metal, a closed deck type cylinder block SC as shown in Fig. 6 is manufactured.In the figure, 6 is a water jacket, 7 is a water hole, and 8 is the top deck part, 9 is the cylinder bore, and 10 is the skirt part.However, in the process block diagram above, a sand mold is used, but the main mold part may be a sand mold or a mold, and the casting method when using a mold is Methods such as gravity casting, low-pressure die-casting, and high-pressure die-casting are used.
It is disclosed in Japanese Patent No. 9-232654. ) (Problems to be Solved by the Invention) However, in such conventional cylinder block manufacturing methods, a core made of sand or the like is used to form the cylinder jacket. For example, when using high-pressure die casting with the intention of improving productivity, a high-strength core that can withstand high molten metal pressure is required, and this core is difficult to remove after casting. There was a problem. On the other hand, with other casting methods that do not require high-pressure molten metal, even if the core problem can be solved, the productivity of the casting method itself is low, and in any case, high efficiency production is difficult. Ta.

This invention was made in view of these conventional problems, and aims to manufacture a cylinder block that can use a highly productive casting method and also that can form a water jacket part without using a core. The aim is to solve the above problems by providing a method.

[Means for Solving the Problems] The present invention achieves the above-mentioned object by a process of casting a two-jacket of an open deck type cylinder block in the casting of a cylinder block having a water jacket, and This method of manufacturing a cylinder block is characterized by including the step of casting a top deck of a top deck of a cast open deck type cylinder block.

(Function) When casting the above-mentioned open deck type cylinder block, well-known casting methods such as sand casting, high-pressure die casting using a metal mold, and so-called pouring mold casting using gravity can be used. It is applicable, but especially when mass producing products with a high degree of rust with high efficiency,
High-speed casting methods such as high-pressure die casting are widely used.

In addition, the metal used to enclose an open deck type cylinder block at the top of its water jacket is not necessarily limited to the same material, and if the welding strength is insufficient due to different materials, it can be reinforced by expanding the area of the welded part. It is.

〔Example〕

The present invention will be explained below based on the drawings.

1 and 2 are diagrams showing one embodiment of the present invention. Note that the same reference numerals are given to the same or equivalent parts as in the prior art.

First, an open deck type cylinder block So shown in FIG. 1 is cast. This is done by injecting the molten metal into a metal mold at high pressure and high speed using a conventionally known die casting machine, such as a cold chamber type. In particular, there is no need to incorporate a water jacket core, quarter-hole core, etc. into the mold, and high-strength cast products can be mass-produced in a short time with a relatively simple mold that is formed only with the main mold.

Next, the top of the water jacket of the cast open deck type cylinder block is filled with a top deck (casting process).

As a mold for this casting process, a top deck forming mold TB shown in FIG. 2 is used. In the figure, 11
12 is a cylinder bore fitting portion, and 12 is a water hole forming portion.

Reference numeral 13 denotes a gas vent hole penetrated through the water hole forming portion 12 to prevent back pressure during casting.

The procedure for casting the top deck part 8 using the above mold T8 for forming the top deck part is performed as follows.

That is, a predetermined amount of the molten metal 14 is poured into the mold TB (FIG. 2(b)). Immediately thereafter, the open deck type cylinder block S0, which has already been cast, is inverted and its top portion is introduced into the mold T8 and placed in a predetermined position (FIG. 2(C)). Since the gas generated in the water jacket part 6 of the sealed mold during the molding process is discharged through the gas vent hole 13,
There is no risk of poor hot water supply due to gas back pressure.

Thereafter, after the molten metal is cooled and solidified in the mold TD, the cylinder block is taken out from the mold T, ) to obtain a cast product of the closed deck type cylinder block SC shown in FIG. 6.

FIG. 3 shows another embodiment.

In this example, in order to ensure the strength of the casting in the top deck part, the open deck type cylinder block S
A convex portion 15 and a notch portion 16 are added to the cast-in portion of 0.

In short, it is sufficient to ensure welding strength by enlarging the welding area of the cast-in part, and of course other deformed shapes (not shown) can also be adopted.

According to each of the above embodiments, a water jacket core made of shell sand or the like, which often causes gas defects, is unnecessary, and gas defects can be prevented.

In addition, in the casting process of each of the above embodiments, an open deck type cylinder block S is used in the mold T0 for forming the top deck part. Needless to say, molten metal may be injected into the mold TO after disposing the mold TO.

In addition, the method for injecting the molten metal into the mold TD is not limited to injection from the upper part of the mold, but also upward injection from the lower part of the mold, as in the case of bottom pressure die casting, for example.

Zarani, open deck type cylinder block S. The constituent metal materials for forming the top deck portion 8 may be different from each other. That is, since the top deck part 8 is not a very important part in terms of strength, it may be made of an inexpensive material.

Furthermore, the shape of the skirt portion 10 of the cylinder block is not limited, and can be applied not only to the half-skirt type illustrated but also to the deep-skirt type.

〔Effect of the invention〕

As explained above, according to the present invention, an open deck type cylinder block is first manufactured, and then, when the top deck part is cast, the top of the face cylinder block is cast to complete the closed deck type cylinder block. This eliminates the need for creating a core to form a water jacket and removing the core after casting is complete, resulting in a highly efficient casting method that achieves high productivity. .

[Brief explanation of the drawing]

FIG. 1(a) is a cross-sectional view of a mold showing a conventional manufacturing method, and FIG. 1(b)
) is a cross-sectional view of the cylinder block made with the mold in (a),
Fig. 1 is a vertical sectional view of an open deck type cylinder block according to the present invention, Fig. 2(a), (b), and (c) are sectional views showing the casting process, and Fig. 2(d) is a longitudinal sectional view of the open deck type cylinder block according to the present invention. c)
FIG. 3 is an enlarged view of part (d) of FIG. 3, and FIG. 3 shows another embodiment according to the present invention, FIG. 2(d) is a partially enlarged view, FIG. 4 is a longitudinal sectional view of a mold in the conventional cylinder block manufacturing method, FIG. 5 is a process block diagram showing an example of the conventional manufacturing process, and FIG. 6 is a FIG. 2 is a longitudinal sectional view of a closed deck type cylinder block. 6 ---- Water jacket 8 ---- Top deck closed deck type cylinder block Figure 2 Figure 1 (a) (C) (d) (14188-P) 7 ``Mr. Kunio Ogawa, Commissioner of the Patent Office
Figure 1, Indication of the incident, 1986 patent application No. 13
No. 1938 02, Title of the invention: Method for manufacturing cylinder blocks 3, Relationship with the amended case Name of patent applicant (399) Nissan Motor Co., Ltd. 4, Agent address: 3-3-14 Shinbashi, Minato-ku, Tokyo Tamuracho Building 5, Date of amendment order: October 27, 1986 (shipment date) 6, Subject of amendment, Contents of amendment 1) Figure 1 of page 8, line 19 to page 9, line 1 of the specification (
(a) is a cross section of the mold showing the conventional manufacturing method, (b) is (a
) is a cross-sectional view of the cylinder block made from the mold. that's all

Claims (1)

[Claims] Casting of a cylinder block having a water jacket includes a step of casting a water jacket of an open deck type cylinder block, and a step of surrounding the top of the water jacket of the cast open deck type cylinder block with a top deck. A method for manufacturing a cylinder block characterized by the following.