JPH02129468A - Steel laminate gasket - Google Patents

Abstract

PURPOSE:To reduce the number of metallic laminated sheets by forming a bead part, surrounding a cylinder bore, in a center plate at a bore seal part where plural numbers of metallic sheets are laminated, while installing a turnup part, covering this bead part, in one side of upper and lower outer plates, and making this turnup part and the outer plate come into a state of not being superposed with each other. CONSTITUTION:A steel laminate gasket has such a structure that a center plate 12 is sandwiched between both upper and lower outer plates 10 and 11, and these three metallic sheets are unified as one body with one another by means of welding or the like, and there is provided with a bore seal part 13 sealing the circumference of a cylinder bore. A bead 12a surrounding this cylinder bore is formed in the center plate 12, and in order to cover this bead 12a, the is provided with a turnup part 11a in a lower outer plate 11. Since an interspace l is kept up between an end of the turnup part 11a and the upper outer plate 10 and they are situated in a nonsuperposed state with each other, the upper outer plate 10 functions as a thickness adjusting plate between the bore seal part 13 and a flat part 14 in consequence. By this constitution, it is unnecessary to install a separate adjusting plate, so that the number of metallic sheets is reduced and simultaneously low-unit cost of production is promoted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a steel laminate gasket constructed by laminating a plurality of metal plates and used as a sealing member of an internal combustion engine.

[Prior Art] Conventionally, a steel laminate type cylinder head gas nut having a metal plate laminate structure of this type is known, for example, as shown in FIGS. 5 and 6.

This gasket has a bead 28 surrounding the cylinder bore formed on the middle plate 2 in the bore seal part 1 that seals around the cylinder bore, and a bead 28 on the lower outer plate 3 and an upper outer plate overlapping the bead 2a on the lower outer plate 3. A folded part 3a is formed to cover the bore seal part 1 and the flat part 5, and the surface pressure in the bore seal part 1 is adjusted by adjusting the thickness between the bore seal part 1 and the other flat part 5 when the gasket is tightened. , an adjustment plate 6 was disposed inside the upper outer panel 4.

However, in such a conventional gasket, since the bent portion 38 of the lower outer plate 3 and the upper outer plate 4 overlap in the bore seal portion 1, the thickness adjustment plate 6 is required, and the metal plate is The disadvantage is that the number of laminated layers increases, making the structure more complex and heavier, and the price also increases. Therefore, there are considerable restrictions on its use in small engines that are required to be lightweight and inexpensive, and this is one of the reasons why steel laminate gaskets are not used in small engines.

Further, the adjustment plate 6 must be located in a non-overlapping state with the folded part 3a, but even if it is in an overlapped state with the folded part 3a due to misalignment, the adjustment plate 6 must be positioned on the inside of the outer panel. It was difficult to check for defects because the

Furthermore, when the gasket is compressed from both sides when in use, the upper outer plate 4 bends sharply at the tip of the folded portion 3a, causing cracks to occur in the bent portion 4a, as shown in FIG. There was a risk that

On the other hand, JP-A-63-101575 discloses a gasket in which the folded portion 3a of the lower outer panel 3 and the upper outer panel 4 are arranged in a non-overlapping state, as shown in FIG. This gasket is attached to the bead 2 by the upper skin 4.
Since the part a is covered, the folded part 3 provided on the lower outer panel 3
This has the disadvantage that it tends to cause stiffness, which leads to a decrease in sealing performance.

[Problems to be Solved by the Invention] An object of the present invention is to reduce the number of laminated metal plates in a steel laminate gasket without reducing the sealing performance in the bore seal portion by improving the structure of the bore seal portion. It is also an object of the present invention to facilitate checking of the mutually overlapping state of the metal plates and to prevent the occurrence of cracks due to deformation of the metal plates.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the gasket of the present invention has a metal plate laminated structure in which a plurality of metal plates are laminated. A bead surrounding the cylinder bore is formed, and a folded part is formed on one of the upper and lower outer plates to cover the bead, and the folded part and the other outer plate are positioned in a non-overlapping state with each other. That is.

[Function] In the above-mentioned steel laminate gasket, in the bore seal part, the folded part formed on one outer plate and the other outer plate are located in a non-overlapping state with each other, so that there is a gap between the bore seal part and the flat part. There is no need for an adjustment plate for adjusting the thickness of the metal plate, so the number of laminated metal plates is reduced, and the structure is simplified, lightweight, and cost-effective. Furthermore, since the folded portion covers the bead, the folded portion is unlikely to sag, and the sealing performance will not deteriorate due to sagging.

In addition, problems caused by the overlapping of the folded part and the outer panel on which the folded part is not formed can be easily checked from the outside.

Furthermore, even if the gasket is compressed from both sides during use, the outer panel will not bend sharply at the overlapped portion with the folded portion, so there will be no possibility of cracks occurring in the outer panel.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

The steel laminate gasket shown in FIG. 1 and JR 2 has a metal plate mya structure in which a middle plate 12 is stacked between upper and lower outer plates 10 and 11 made of metal plates, and each of these plates 10, 11 and 12 are integrated with each other by spot welding or the like, and is provided with a bore seal portion 13 that seals around the cylinder bore.

In the bore seal section 13, a bead 12a surrounding the cylinder bore is formed in the middle plate 12, and a folded part 11a covering the bead 12a is formed in the lower outer plate 11, and the ends of the folded part 118 and the upper A spacing is maintained between the folded portion 11a and the upper outer panel 10, and this spacing allows the folded portion 11a and the upper outer panel 10 to be positioned in a non-overlapping state with each other.

The above interval sentence tightens the gasket (see Figure 3)
In this case, any size may be used as long as the folded portion 11g and the upper outer panel 10 do not overlap, but usually it is 0.05 to 2.
It is set to about hm. Also, the thickness t of the upper outer panel 10
Thickness t2 of the lower outer plate 11 forming the folded portion 11a
It is desirable to set the relationship t2>t+.

The above steel laminate gasket is for the bore seal part 1.
3, the folded portion 11a formed on the lower outer panel 11 and the upper outer panel 10 are located in a non-overlapping state with each other,
When tightening the gasket (see Fig. 3), the upper outer plate 10 essentially functions as a thickness adjustment plate between the bore seal portion 13 and the flat portion 14, so that a conventional adjustment plate is not required. There is no need to provide a separate one.

Furthermore, any defects caused by the overlap between the upper outer panel 10 and the folded portion 11a can be easily checked from the outside.

FIG. 4 shows a second embodiment of the present invention, and the difference from the first embodiment is that a second intermediate plate is provided between the middle plate 22 on which the bead 22a is formed and the lower outer plate 21. 25, and other configurations, namely, the folded part 2 on the lower outer panel 21.
1a is formed, and the folded portion 21a and the upper outer plate 20 are positioned in a non-overlapping state, which is the same as in the first embodiment.

In each of the above embodiments, the folded portions 11a and 21a are formed on the lower outer panel 11.21, but the folded portions 11a and 21a are formed on the lower outer panel 10.21.
This folded portion may be formed on the 20 side.

[Effects of the Invention] According to the steel laminate gasket of the present invention detailed above, in the bore seal portion, the folded portion formed on one outer plate and the other outer plate are positioned in a non-overlapping state with each other. To eliminate the need for an adjustment plate for adjusting the thickness between the bore seal part and the flat part, thereby reducing the number of laminated metal plates, simplifying the structure, reducing weight, and lowering the price. It's coming. Moreover, since the bead is covered by the folded part, the folded part does not become loose.
, no deterioration in sealing performance due to settling.

In addition, problems caused by the overlapping of the folded part and the outer panel on which the folded part is not formed can be easily checked from the outside.

Furthermore, even if the gasket is compressed from both sides during use, the outer panel will not bend sharply at the overlapped portion with the folded portion, so there is no risk of cracks occurring in the outer panel.

[Brief explanation of the drawing]

FIG. 1 is a partial plan view showing the first embodiment of the present invention, 882
The figure is an enlarged sectional view taken along the line A-A in Figure 1, Figure 3 is a sectional view of the main part in the state of tightening, and Figure j84 is the same position as Figure 2 showing the second embodiment of the present invention. 5 is a partial plan view of the conventional example, FIG. 6 is an enlarged sectional view taken along the line B-B, and FIG. 7 is a sectional view of the main part showing the state of tightening. FIG. 8 is a partial sectional view of another conventional example. 10.20 - Upper outer panel. 11.21 - Lower outer plate, 11a, 21a - Turned part, 12.22 - Middle plate. 12a, 22a...bead, 13...bore seal part.

Claims (1)

[Claims] 1. In the bore seal part that has a metal plate laminated structure made of multiple metal plates and seals around the cylinder bore,
A bead surrounding the cylinder bore is formed in the middle plate, and a folded part covering the bead is formed in one of the upper and lower outer plates, and the folded part and the other outer plate are positioned in a non-overlapping state with each other. A steel laminate gasket characterized by: