JP2995592B2 - Manufacturing method of metal gasket - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a metal gasket, and more particularly, to a cylinder head gasket for an internal combustion engine, in which a fluid hole is formed in a metal substrate and a bead is formed around the fluid hole. The present invention relates to a method for manufacturing a suitable metal gasket.

[0002]

2. Description of the Related Art It is well known that a gasket is interposed between joining members to prevent leakage of a pressure fluid from a joining surface. For example, a gasket is provided between a cylinder head and a cylinder block of an internal combustion engine. A cylinder head gasket is interposed. With regard to this type of gasket, a metal gasket made of a metal plate has recently attracted attention.

[0003] For example, a fluid hole through which a pressure fluid such as a combustion gas passes is formed in a metal substrate, and a bead is formed around the fluid hole so that a high surface pressure can be secured to a joining member. Is known. Furthermore, the actual opening 59-18
As disclosed in JP-A-8955, in order to prevent the bead from being plastically deformed by the tightening force and deteriorating the sealing performance with respect to the metal gasket, a surface pressure adjustment made of a plate thinner than the protruding height of the bead. It has been proposed to provide a plate at a portion other than the bead.

In such a metal gasket, a soft sealing material is adhered to the surface of a substrate in order to improve sealing properties, and a coating layer, that is, a sealing film is formed. Therefore, a seal film is also formed on the bead and the surface pressure adjusting plate.

[0005]

However, in the case of a metal gasket in which a seal film is formed on the surface of the bead projecting side of the substrate, the top of the bead projecting from the substrate surface is the highest. Rubbing occurs between the top and the upper surface of the conveyor, and rubs on the front and back sides when stacked and stored or transported. The film is liable to be scratched or peeled off, and it is difficult to ensure a certain level of sealing performance. Similarly, since the above-mentioned surface pressure adjusting plate is lower than the bead but protrudes from the substrate, the sealing film on the top thereof is easily damaged or peeled off.

Accordingly, the present invention is directed to a metal gasket in which a fluid hole is formed in a metal substrate, a bead is formed around the metal hole, and a seal film is formed on the surface of the substrate including at least the protrusion side of the bead. It is an object of the manufacturing method to manufacture the sealing film on the top of the bead so that the sealing film can be prevented from being scratched or peeled off.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a substrate having a fluid hole through which a pressurized fluid passes, and forming a bead protruding around the fluid hole. In the method for manufacturing a metal gasket for forming a seal film on the surface of the substrate including the projecting side of the bead, the rolled metal plate is punched into a predetermined shape to form the substrate, and the rolled metal plate is wound in the winding direction. The bead is formed so as to protrude toward the curved concave side of the substrate with respect to the substrate curved along.

The present invention is also directed to a method for forming a pair of substrates which are formed by punching a rolled metal plate into a predetermined shape and which is curved along a direction in which the rolled metal plate is wound. A fluid hole through which a fluid passes is formed, and a bead is formed around the fluid hole so as to protrude toward the curved concave side of each of the pair of substrates, and a bead is formed on at least one of the pair of substrates. A metal gasket may be formed by forming a seal film on at least the surface including the projecting side of the bead, and joining the pair of substrates so that the beads face each other.

Further, according to the present invention, a fluid hole through which a pressure fluid passes is formed in a substrate, a bead is formed around the fluid hole, and a seal is formed on a surface of the substrate including at least a projecting side of the bead. In the method of manufacturing a metal gasket for forming a film, at least a part of an outer peripheral end of the substrate is bent at least to a projecting side of the bead to form a support having a height greater than the height of the bead. You may do it.

[0010]

In the method for manufacturing a metal gasket of the present invention, a rolled rolled metal plate is punched into a predetermined shape, and a fluid hole through which a pressure fluid passes is formed to form a substrate. This substrate is curved along the winding direction of the rolled metal plate, and a bead is formed around the fluid hole so as to project toward the curved concave side. Then, a seal film is formed on the surface of the substrate including at least the projecting side of the bead.

The substrate manufactured in this manner is supported by both ends even if it is arranged on a horizontal plane such that the bead projecting side is downward, so that the top of the bead projecting toward the curved concave side of the substrate is There is no contact with the horizontal plane. That is, the substrate is supported at both ends, and when forming a seal film on the surface of the substrate including the projecting side of the bead, a predetermined seal film is formed without the top of the bead contacting the upper surface of the conveyor or the like. . When the metal gasket is transported and assembled between the joining members, only the both ends of the substrate come into contact with the assembly line and the like, and the contact of the top of the bead can be avoided. Is maintained. Further, the two substrates thus formed can be joined so that each bead faces each other to form one metal gasket.

When the metal gasket is interposed between the joining members, for example, between the cylinder head and the cylinder block, and the two are fastened with a predetermined tightening force, the bead is compressed and its elasticity is reduced. A predetermined surface pressure on the joining member is secured by the restoring force. At this time, since the sealing film is formed on the contact surface including the bead top and the joining member,
Even if the joining surface of the joining member is rough, the joining members adhere to each other and a good sealing property is secured.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a method for manufacturing a metal gasket according to the present invention. As the metal gasket to be used in the present invention, for example, a cylinder head gasket interposed between a cylinder head and a cylinder block of a multi-cylinder internal combustion engine is preferable. A method for manufacturing a gasket will be described.

The raw material to be used in the present invention is a rolled metal plate in which the stress at the time of manufacturing the plate material remains, and is provided in the form of a coil. And the thing which can curve along the winding direction as the residual stress of the board | plate material is selected. Here, there are two types that bend along the winding direction, one having a stress that curves inward in the winding direction, and the other having a stress that curves outward in the winding direction. Things. The case where the former type is used will be described below, but it goes without saying that the latter type may be used.

FIG. 1 shows a part of an apparatus provided for an embodiment of a method for manufacturing a metal gasket according to the present invention. The apparatus includes a long rolled metal plate, for example, a stainless steel plate (SUS) material 2.
Is wound in a roll shape, and is supported by the support device 3 so as to be rotatable around the axis of the coil. The material 2 is guided by a guide 4, and is fed by a feeder 5 to a first pressing device 6.
Are supplied at predetermined intervals. In the first press device 6, a blanking process is performed on the material 2 to form a substrate 10 having a plurality of combustion chamber holes 11 and the like as shown in FIG. That is, at the same time when a substantially rectangular substrate 10 is punched from the raw material 2, the number of combustion chamber holes 11 corresponding to the number of cylinders (for example, four for an in-line four-cylinder internal combustion engine) is formed in the substrate 10.
Are arranged side by side on the longitudinal axis. At the same time, the substrate 10
Are provided with a plurality of cooling water holes (not shown) and lubricating oil holes (not shown), and a plurality of bolt holes 12. The punched substrate 10 is curved along the winding direction of the material 2. That is, since the present embodiment is of a type having a stress that curves inward in the winding direction, the material 2 is curved in the width direction so that the lower side is the concave side in FIG. In addition, instead of the processing by the first press device 6,
The cutting may be performed by a laser cutting device or the like.

Subsequently, the bead 13 shown in FIGS. 3 and 4 is formed around each combustion chamber hole 11 of the substrate 10 while being supplied to the second press device 7 shown in FIG. A bead 14 is formed on the substrate. In this case, the bead 13 is formed so as to protrude toward the curved concave side of the substrate 10, but the curved state of the substrate 10 is maintained. Since the bead 14 has only one bent portion, the bead 13 is also called a half bead with respect to the bead 13. Although the equipment is not shown in FIG. 1, the substrate 10 is transported to the coating apparatus 8 after the entire substrate 10 is cleaned and subjected to a predetermined heat treatment if necessary. , And seal films 30 are formed on both surfaces of the substrate 10 as shown in FIG.

In the coating apparatus 8, as shown in FIG. 2, a liquid sealing material such as an unvulcanized fluorine-based rubber is sprayed from a supply apparatus 8a to form a sealing film 30 on the surface of the substrate 10. Note that, instead of the spray-type supply device 8a, a coating device (not shown) having a supply device on the upper side and a storage device on the lower side may be used. In the same device, the sealing material is continuously flowed down from the supply device to form a film-like flow lower surface in the vertical direction, and the sealing material that has flowed down to the storage device disposed on the lower side is returned to the supply device,
A film-like flow lower surface is always formed. In addition, a pair of conveyors 8c and 8d for conveyance are installed substantially horizontally adjacently. The substrate 10 supplied to the coating device 8 is once inverted so that the surface on the projecting side of the bead 13 faces upward, and is transported by the conveyor 8c in the direction of the supply device 8a. When the substrate 10 passes through the lower surface of the film, the sealing material spreads on the surface of the substrate 10 to form a film,
The seal film 30 is formed uniformly. It is needless to say that a drying operation or a solidifying operation accompanying the coating step may be performed as necessary.

After the sealing film 30 is formed on the surface of the substrate 10 on the side where the beads 13 protrude, the substrate 10 is turned over again, transported in the opposite direction, and passes below the supply device 8a. At this time, since the substrate 10 is supported on the conveyors 8c and 8d with both ends, the top surface of the bead 13 does not contact the conveyors 8c and 8d. Thus, FIG.
As shown in FIG. 7, a seal film 30 is also formed on the surface of the substrate 10 opposite to the side where the beads 13 protrude. Thereafter, the seal films 30 formed on both surfaces of the substrate 10 are solidified by a vulcanization treatment as needed. The thickness of the sealing film 30 is
It can be set as appropriate by adjusting the amount of the sealing material sprayed from the supply device 8a, the conveying speed of the conveyors 8c and 8d, and the like. The coating on the substrate 10 may be performed on only one surface of the substrate 10 by the above-described spray type supply device 8a or an apparatus for forming a film-like flow lower surface.

When the defective rate of the seal film 30 in the metal gasket 1 thus formed is compared with that of the conventional example, the metal gasket in which the projecting side of the bead 13 is formed on the curved convex side of the substrate 10 is 20 to 30. %, Whereas in the present example, it was reduced to 0.5% or less. Further, when the metal gasket 1 is placed on a conveyor or stacked on another metal gasket at the time of transporting or assembling the metal gasket 1, the substrate 10 is supported by both ends, so that the top of the bead 13 Is prevented from coming into contact with the surface of the substrate 10 including
There will be no scratches or peeling off.

The metal gasket 1 configured as described above
Is inserted with a fastening bolt (not shown), for example, is arranged such that the projecting side of the bead 13 is on the side of the cylinder block (not shown), and is tightened between the cylinder head (not shown) and the cylinder block. Specifically, when a tightening force is applied to the substrate 10, the sealing film 30 on the top surface of the bead 13 is formed.
Adheres to the joint surface of the cylinder block (not shown), and the bead 13 is deformed. When the cylinder head and the cylinder block are tightened, the substrate 10
The cylinder comes into close contact with the cylinder block due to the elastic restoring force. Thus, a predetermined surface pressure of the metal gasket 1 is secured around each combustion chamber hole 11 by the bead 13. In addition, since the sealing film 30 is uniformly formed on the entire surface of the substrate 10 including the beads 13, even if the joint surface between the cylinder head and the cylinder block is rough, the sealing film 30 can be in close contact with each other and good sealing properties can be obtained.

FIGS. 5 to 7 relate to another embodiment of the present invention, in which two substrates 10a and 10b are joined to form a metal gasket 1a. The cylinder head and the cylinder block in the state shown in FIG. Interposed in between. Substrate 10
a and 10b are basically the same as the configuration of the substrate 10 shown in FIGS. 3 and 4, but both have asymmetric shapes in the axial direction, and have a curved concave side of one substrate 10a and the other substrate. 10b are joined so that the curved concave side faces each other. Therefore, as shown in FIG. 6, both ends in the longitudinal direction of the substrates 10a and 10b come into contact with each other. 5 to 7, the letter a is attached to one of the substrates and the letter b is attached to the other of the symbols in FIGS. 3 and 4.
However, in FIG. 5, the bead 14a is shown by a dashed line.

On the substrate 10a, a so-called shim ring 20, which is a spacer made of, for example, a stainless steel plate, is joined to a flat surface extending from the bead 13a to the combustion chamber hole 11a on the protruding side of the bead 13a. Is done. That is, FIG.
As shown in FIG. 5, the shim ring 20a thinner than the protrusion of the bead 13a is substantially continuously welded to the substrate 10a over the entire circumference by the welding machine 9x as described later. Therefore,
A continuous welded portion 21 is formed all around the annular shim ring 20.

FIG. 8 shows the two substrates 10 shown in FIG.
1A and 1B show a manufacturing process of a metal gasket 1a for joining the two substrates 1a and 10b.
An assembling machine 9 for joining Oa and 10b is arranged in the final step. Further, a welding machine 9x is arranged in the manufacturing process of the substrate 10a. The devices corresponding to the respective devices shown in FIG. 1 are indicated by adding a or b to the reference numerals of the respective devices in FIG. 1, but these are substantially the same, and the upper part of FIG. Is shown, and the lower stage shows the substrate 10b.
2 shows a process for manufacturing. In particular, the shape of the punching die of the upper first pressing device 6a and the shape of the lower pressing device 6b are the same.

As is apparent from a comparison between the above two steps,
The upper material 2a is supported by the support device 3a so as to be pulled out from above the coil as in the embodiment of FIG. 1, while the lower material 2b is supported by the support device 3b so as to be drawn from below the coil. ing. That is, feeder 5
The raw material 2b supplied to the first press device 6b from b.
The substrate 10a conveyed to the second pressing device 7a has the same relationship as being wound in the opposite direction to the material 2a, and the first pressing devices 6a and 6b have the same cutting die. Has a curved concave portion below, while the second
The substrate 10b conveyed to the press device 7b has a curved concave portion located above. Therefore, in the second press device 7b, the bead 13b is formed so as to protrude upward in the same direction as the curved concave portion of the substrate 10b. For this reason, the lower second
In the press device 7b, the mold for forming the bead 13b is provided so that the bead forming direction is upside down with respect to the upper press device 7a.

In the upper step, a welding machine 9x, for example, a pulse-driven laser welding machine is provided, and the substrate 10 on which the beads 13a are formed by the second pressing device 7a.
and the shim ring 20 is welded substantially continuously around the combustion chamber hole 11a. Therefore, the substrate 10a is not inverted, is washed as it is, and is subjected to a heat treatment as necessary. Then, the substrate 10a is conveyed to the coating device 8a, and the seal film 30 is formed in order from the surface on the projecting side of the bead 13a.

Thus, the substrates 10a and 10b are respectively applied to the sealing films 30a and 30b via the coating devices 8a and 8b.
Are formed by the assembling machine 9 so that the curved concave portions are opposed to each other as shown in FIGS. 5 and 6, and although not shown in FIGS. 5 to 7, the substrates 10a and 10b
At the end of As means for joining the ends of the substrates 10a and 10b in the assembling machine 9,
In addition to caulking, welding, bonding or the like may be used.

Material 2b supported by the support device 3b
May be arranged so as to be pulled out from above in the same manner as the material 2a, but in this case, the cutting die of the lower first pressing device 6b in FIG. 8 is replaced with the cutting die of the upper first pressing device 6a. On the other hand, it is necessary to form them so as to be symmetric about the axis of the substrate 10a. Regarding the bead forming die of the second press device 7b, even if the bead forming direction is the same as that of the second press device 7a, depending on the shape of the substrates 10a and 10b, the bead 13b is formed at the bead 13a forming position. Therefore, it is necessary to form the mold so that the formation position of the bead 13b is a predetermined position. In addition, the substrate 1
The seal film 30 may not be formed on the entire surface of the protrusion 0b or on the surface of the bead 13b on the protruding side.

The metal gasket 1a is interposed between the cylinder head and the cylinder block, and a tightening force is applied. As shown in FIG. 7, the tops of the beads 13a and 13b come into contact with each other and the shim ring 20 is compressed. Then, the deformation of the beads 13a, 13b does not proceed any further, and a high surface pressure is secured by the elastic restoring force of the beads 13a, 13b. The surface pressures of the beads 14a and 14b are also combined.

FIG. 9 shows an embodiment of a metal gasket manufactured by another manufacturing method of the present invention, and is effective when the substrate is formed in a flat plate shape without being formed in a curved shape. That is, a plurality of tongue-shaped support portions 15c are formed on the outer peripheral end of the flat substrate 10c so as to extend in the same direction as the bead projecting direction (downward in FIG. 9). The height of the support portion 15c from the substrate 10c is set to be larger than the height of the bead. Thus, in this embodiment, the support portion 15c
Are two on each of the left and right sides in the longitudinal direction of the substrate 10c as shown in FIG.
And one each in the width direction. According to the present embodiment, even if the substrate 10c is a flat substrate, it is possible to prevent the top of the bead from contacting a conveyor or the like. The support 15
Since c is provided on the outer peripheral end of the substrate 10c and is provided outside the range of the joint surface with the cylinder head and the cylinder block, c is not sandwiched between them.

FIG. 10 shows another embodiment of a metal gasket manufactured by another manufacturing method of the present invention. The metal gasket is provided on a support portion 15c extending to the projecting side (below in FIG. 10) of the bead of the substrate 10c. In addition, a support portion 16c extending to the opposite side (upward in FIG. 10) from the bead projecting side is formed by bending. According to this embodiment, the substrate 10
The entire seal film uniformly formed on both surfaces of the layer c can be protected. In each of the embodiments shown in FIGS. 9 and 10, the supporting portions 15c and 16c are formed integrally with the substrate 10c. However, these may be formed separately and a resin member may be bonded. Further, the support portions 15c, 16
The length, number, and position of c are not limited to those in the above embodiment,
It can be set appropriately according to the situation at the time of manufacture, transportation, assembly and the like.

[0031]

Since the present invention is configured as described above, the following effects can be obtained. That is, according to the metal gasket manufacturing method of the present invention, the substrate is formed so as to be curved and the bead is formed so as to protrude toward the curved concave side of the substrate, or the height of the bead is increased at the outer peripheral end of the substrate. Since a larger supporting portion is provided, it is possible to prevent the sealing film formed on the bead projecting side of the substrate from being scratched or peeled off during manufacturing, transporting, assembling, etc. Nature can be secured.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a main part of a manufacturing process in one embodiment of a method for manufacturing a metal gasket of the present invention.

FIG. 2 is an explanatory diagram showing details of a coating apparatus in FIG. 1;

FIG. 3 is a perspective view of a metal gasket manufactured by a manufacturing method according to an embodiment of the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a perspective view of a metal gasket manufactured by a manufacturing method according to another embodiment of the present invention.

FIG. 6 is a cross-sectional view of a metal gasket manufactured by a manufacturing method according to another embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a state at the time of joining two substrates along the line BB in FIG. 5;

FIG. 8 is an explanatory view showing a main part of a manufacturing process in another embodiment of the method for manufacturing a metal gasket of the present invention.

FIG. 9 is a perspective view of an embodiment of a metal gasket manufactured by a manufacturing method according to still another embodiment of the present invention.

FIG. 10 is a perspective view of another embodiment of a metal gasket manufactured by a manufacturing method according to still another embodiment of the present invention.

[Explanation of symbols]

 1,1a Metal gasket 2,2a, 2b Material 3,3a, 3b Supporting device 4,4a, 4b Guide 5,5a, 5b Feeder 6,6a, 6b First pressing device 7,7a, 7b Second pressing device 8, 8a, 8b Coating device 9 Assembling machine 9x Welding machine 10, 10a, 10b, 10c Substrate 11, 11a, 11b, 11c Combustion chamber hole (fluid hole) 13, 13a, 13b, 13c Bead 15c, 16c Support portion 20 Shim ring 30, 30a, 30b Seal film

Claims (3)

(57) [Claims] 1. A fluid hole through which a pressure fluid passes is formed in a substrate, a bead is formed around the fluid hole, and a seal film is formed on a surface of the substrate including at least a projecting side of the bead. In the method for manufacturing a metal gasket, the rolled metal plate is punched into a predetermined shape to form the substrate, and the bead is bent along the winding direction of the rolled metal plate. A method for manufacturing a metal gasket, wherein the metal gasket is formed so as to protrude toward a concave side. 2. A rolled rolled metal plate is punched into a predetermined shape to form a pair of substrates curved along the direction of winding of the rolled metal plate, and pressurized fluid passes through each of the pair of substrates. A fluid hole is formed, and a bead is formed around the fluid hole so as to protrude toward the curved concave side of each of the pair of substrates, and at least the bead of at least one of the pair of substrates is formed. Forming a seal film on a surface including a projecting side of the metal gasket, and bonding the pair of substrates so that respective beads face each other to form a metal gasket. 3. A fluid hole through which a pressure fluid passes is formed in the substrate, a bead is formed around the fluid hole, and a seal film is formed on a surface of the substrate including at least a projecting side of the bead. In the method for manufacturing a metal gasket, at least a part of an outer peripheral end of the substrate is bent at least to a projecting side of the bead to form a support having a height greater than the height of the bead. Of manufacturing a metal gasket.