JPS5832530A - Die for metallic gasket and its forming method - Google Patents

Abstract

PURPOSE:To obtain a presice die for metallic gaskets easily at low cost by forming slits which correspond to necessary beads in two base plates and implanting steel plates therein, and forming steps, opposed with intermediate plates between, between the base plates and pedestals. CONSTITUTION:In two metallic base plates 10 and 10', slits 11 and 11' facing to each other are formed, and steel plates 12 and 12' are embedded therein. Those base plates 10 and 10' are fixed to pedestals 15 and 15' through bolts 16. An intermediate plate 17 is interposed between a part 10b of the base plate 10, divided by the slit 11, and the pedestal 15 to form a step (h). Further, an intermediate plate 17' is provided between a part 10a of the other substrate 10' and the pedestal 15' to form the opposite step (h'). A slanting edge 18 facing the base plates 10 and 10' is fomed at need to obtain a die for matallic gaskets. This method forms the die for metallic gaskets of cylinder heads, etc., easily and accurately. This die is reproduced easily.

Description

[Detailed description of the invention] It is about the method.

Generally, it is well known that metal gaskets for cylinder heads of internal combustion engines are press-molded using a pair of molds consisting of a male mold and a female mold.

Particularly in motorcycle engines, parallel multi-cylinder engines have become commonplace, and as a result, the shape of metal gaskets for cylinder heads has become complex, and there is a growing demand for improved performance. The shape has also become more complex.

Therefore, as in the conventional molding method, a male mold protrusion is formed on one of a pair of substrates by cutting from the substrate, while four female mold portions are bored in the other substrate. However, since both of them had to be opposed to each other with high precision, molding required a great deal of labor and time, making it extremely expensive.

Furthermore, since the mold wears out during a certain stage of use, it is necessary to manufacture a new mold, which requires the same labor and time as mentioned above, so the cost is transferred to the metal gasket as a product. It had to be a powerful event.

The present invention aims to reliably eliminate the above-mentioned drawbacks and provide a mold for this type of metal gasket that is easy to manufacture and has high precision. Accurately drill a pea-shaped slit with a wire cutter, etc., and have a thickness that corresponds to the slit.
In addition, a steel plate with the same width as the original board is buried in the slit, while an intermediate plate of the required thickness is interposed between one of the board parts divided by the slit, and the side board part is attached to a single pedestal with bolts, etc. A step is formed on the surface of the substrate to form a male mold and a female mold, and if necessary, one side of the slit is cut with a drill or the like. This has succeeded in saving labor and time and providing a precision mold.

The gist of the present invention will be explained in detail below with reference to embodiments shown in the drawings.

FIG. 1 is a partially cutaway plan view showing an embodiment of a metal gasket for a motorcycle four-cylinder engine/engine according to the present invention;
The figure is a sectional view taken along the line A-A in Figure 1, and as is clear from these figures, the metal gasket 1 consists of a hard metal main plate a at the center and two soft metal sub-plates A and B. a
Pinide 2 is formed.

As shown in FIG. 6, the mold of the present invention for molding a pea 2 with a slit 2 is provided with two iron substrates 10 and 10'iC1 having slits 11 and 11' facing each other. Steel plates 12 and 12' are embedded in 11 and 11', and the steel plates 12 and 12' are formed to have the same width W as the thickness d of the iron substrates I0 and 10'.

Reference numerals 15 and 15' denote pedestals for fixing the iron substrates 10 and 10', respectively, and fix the substrates io and io' through bolts 16. As mentioned above, the substrate 10 is divided into parts separated by the slits 11. Therefore, each part is fixed onto the pedestal 15 via bolts 16 so that they will not be separated from each other.

In order to form a step of pea 2 when fixing to the pedestal 15, the substrate portion 1Q divided by the slit 11 is
A and 10b, an intermediate plate 17 is interposed between the substrate portion 10b and the pedestal 15 to form a step, and for the other substrate 10', the substrate portion 10'a and the pedestal 1
5', and it goes without saying that h=h'. However, if necessary, cutting the edge of the substrate portion 10'a facing the slit 11' to provide a beveled edge 18 will make the shape of the bead 2 accurate, but this is not necessarily necessary.

However, it goes without saying that the beveled edges 18 can be formed on the side substrates 10 and 10/ so as to face each other, if necessary.

In short, slit 1 corresponds to the shape of pea 2.
1, 11' width, intermediate plate 17.17. This kind of mold can be manufactured very easily by taking into consideration the thickness of the rim 18, the angle of the beveled edge 18, etc.

As mentioned above, the mold of the present invention forms slits 11 and 11' of the same shape that face each other in a pair of iron substrates, and is formed from a steel plate 12 and an intermediate plate 18 based on this. Therefore, the mold can be formed easily and accurately, and the bolts can be unscrewed and the steel plates 12 and 12' can be mounted on the pedestals 15 and 15', respectively, to prevent wear of the mold.
If the thickness d is reduced by cutting or polishing the entire substrate 10°10', it is easy to regenerate the product. Compared to the conventional molds of this type, the present invention provides a new mold with outstanding accuracy. Moreover, since it is easy to mold, it not only can be appropriately adapted to complex gasket structures, but also has many excellent characteristics, such as being able to withstand long-term use.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway plan view of a metal gasket of a motorcycle Kawanishi cylinder engine manufactured using the mold of the present invention, Fig. 2 is an enlarged sectional view of the section taken along line A-A in Fig. 1, and Fig. 6 is the main FIG. 2 is an enlarged sectional view showing the main parts of the invention mold. 1~Metal gasket 2~Bead 10~Iron substrate 11~Slit 12~Steel plate 15
~ Pedestal 16 ~ Port 17 ~ Intermediate plate 18 ~ Diagonal edge a ~ Hard metal plate b ~ Soft metal plate August 19, 1981 Patent applicant Nippon Metal Gasket Co., Ltd. 135
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Claims (3)

[Claims] (1) A slit corresponding to the shape of the required bead is made in two iron substrates, a steel plate is buried in the slit, and the steel plate is fixed to a pedestal, and one of the substrates divided by the slit is A step is formed by interposing an intermediate plate,
Furthermore, the metal gasket mold is characterized in that it consists of a male die and a female die, which are opposed to each other with the steps of the two substrates being different from each other. (2) In at least one of the substrates, a protruding side edge of a slit with a step formed on the surface with an intervening intermediate plate is cut diagonally to form a diagonal edge opposite to the diagonal direction of the bead. A metal gasket mold according to claim 1. (3) Drill slits corresponding to the required beads in two iron substrates, drive a steel plate into the slits in each substrate, and interpose an intermediate plate between the parts of one of the substrates divided by the slits in each substrate. A method for manufacturing a mold for a metal gasket, which comprises fixing it to a pedestal and at the same time forming mutually opposing steps on the surface of the substrate (an intermediate plate is interposed between the pedestal and the substrate, respectively).