JPH05133473A - Manufacturing method of metal gasket - Google Patents

Abstract

(57) [Abstract] [Purpose] In a method of manufacturing a metal gasket in which a sealing film is formed on a substrate surface at least on a protruding side of a bead, it is possible to prevent scratches and peeling of the sealing film with a simple configuration. [Structure] A rolled metal sheet material (2) wound into a roll is punched into a predetermined shape by a first pressing device (6) to form a substrate (10), and a fluid hole (11) through which a pressure fluid passes. ) Is drilled. The substrate (10) is curved in the winding direction of the material (2), and a bead (13) is formed so as to protrude toward the curved concave side of the material (2) by the second pressing device (7). Then, in the coating device (8), at least the bead (1) of the substrate (10) is
The seal film (3) is formed on the surface of the substrate (10) including the protruding side of (3).
0) is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a metal gasket, and more particularly, as 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 preferable method for manufacturing a metal gasket.

[0002]

2. Description of the Related Art It is well known that a gasket is interposed between joint members in order to prevent leakage of pressure fluid from the joint surface, for example, between a cylinder head and a cylinder block of an internal combustion engine. A cylinder head gasket is installed. With respect to this type of gasket, a metal gasket made of a metal plate material has recently been drawing attention.

For example, a metal substrate is provided with a fluid hole through which a pressure fluid such as combustion gas passes, and a bead is formed around the fluid hole so that a high surface pressure can be secured for the joining member. What you have done is known. Furthermore, the actual development Sho 59-18
As disclosed in Japanese Patent No. 8955, in order to prevent the bead from plastically deforming due to a tightening force and deteriorating the sealing property with respect to the metal gasket, a surface pressure adjustment made of a plate thinner than a protruding height of the bead. It is also proposed that the plate is provided on a portion other than the bead.

In such a metal gasket, in order to improve the sealing property, a soft sealing material is attached to the substrate surface to form a coating layer, that is, a sealing film. Therefore, the sealing film is also formed on the beads and the surface pressure adjusting plate.

[0005]

However, in a metal gasket having a sealing film on the bead protruding side of the substrate, the top of the bead protruding from the substrate surface is the highest. Rubbing occurs between the top and the top of the conveyor, and when they are stacked and stored or conveyed, they rub against each other on the front and back surfaces, and when they are assembled between joining members, they rub on the assembly line to seal the bead top. The film is likely to be scratched or peeled off, and it is difficult to secure a certain quality with respect to its sealing property. Similarly, since the above-mentioned surface pressure adjusting plate is lower than the bead but protrudes from the substrate, the seal film on the top thereof is likely to be damaged or peeled off.

In view of the above, the present invention provides a metal gasket in which a fluid hole is formed in a metal substrate, and a bead is formed to project around the fluid hole, and a sealing film is formed on the surface of the substrate including at least the projecting side of the bead. In the manufacturing method, it is an object of the manufacturing method to prevent scratches and peeling of the seal film on the top of the bead.

[0007]

In order to achieve the above-mentioned object, the present invention provides a substrate with a fluid hole through which a pressure fluid passes, and forms a bead around the fluid hole to form at least the bead. In a method for manufacturing a metal gasket that forms a seal film on the surface of the substrate including the protruding side of the bead, the rolled 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 project toward the curved concave side of the substrate with respect to the substrate that curves along the line.

Further, according to the present invention, the rolled rolled metal sheet is punched into a predetermined shape to form a pair of substrates curved along the winding direction of the rolled metal sheet, and pressure is applied to each of the pair of substrates. A fluid hole through which a fluid passes is formed, and beads are formed around the fluid hole so as to project to the curved concave side of each of the pair of substrates, and at least one of the pair of substrates is formed. A sealing film may be formed on a surface including at least the protruding side of the bead, and the pair of substrates may be joined so that the respective beads face each other to form a metal gasket.

Further, according to the present invention, the substrate is provided with a fluid hole through which a pressure fluid passes, a bead is formed so as to surround the fluid hole, and a seal is provided on the surface of the substrate including at least the projecting side of the bead. In a method of manufacturing a metal gasket for forming a film, at least a part of an outer peripheral end of the substrate is bent toward a protruding side of the bead to form a support part having a height larger than a height of the bead. It may be done.

[0010]

In the method of manufacturing the metal gasket of the present invention, the rolled rolled metal plate is punched into a predetermined shape, and the substrate is formed by forming the fluid holes through which the pressure fluid passes. 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 to the curved concave side. Then, a seal film is formed on the surface of the substrate including at least the protruding side of the bead.

The substrate manufactured in this manner is supported by both ends of the substrate even if it is arranged on a horizontal plane so that the projecting side of the bead faces downward. Therefore, the top of the bead projecting toward the curved recess side of the substrate is There is no contact with the horizontal surface. That is, the substrate is supported on both ends, and when forming the seal film on the surface of the substrate including the protruding side of the bead, the predetermined seal film is formed without the top of the bead contacting the upper surface of the conveyor or the like. .. Then, 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. Maintained at. Further, the two substrates thus formed can be joined so that their beads are opposed to 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. The restoring force ensures a predetermined surface pressure on the joining member. At this time, since the seal film is formed on the contact surface including the bead top portion with the joining member,
Even if the joint surfaces of the joint members are rough, they adhere to each other and ensure good sealability.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method for manufacturing a metal gasket of the present invention will be described below with reference to the drawings. As the metal gasket of 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 suitable, and in the following, a metal used as a cylinder head gasket is used. A method of manufacturing the gasket will be described.

The material to be used in the present invention is a rolled metal plate in which the stress during the production of the plate material remains, and the material is wound in the form of a coil. The residual stress of the plate material is selected so that it can be curved along the winding direction. Here, there are two types of curving along the winding direction, one having a stress bending inward in the winding direction and the other having a stress bending outward in the winding direction. It is a thing. The case of using the former type will be described below, but it goes without saying that the latter type may be used.

FIG. 1 shows a part of an apparatus used in an embodiment of the method for producing a metal gasket of the present invention, which is a raw material 2 of a long rolled metal plate, for example, a stainless steel plate (SUS).
A coil formed by winding in a roll shape is supported by the support device 3 so as to be rotatable about the axis of the coil. The material 2 is guided by the guide 4 and is fed by the feeder 5 to the first pressing device 6
Is supplied every predetermined length. In the first press device 6, the blank 2 is punched to form a substrate 10 having a plurality of combustion chamber holes 11 and the like as shown in FIG. That is, the substantially rectangular substrate 10 is punched out from the material 2, and at the same time, 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 provided on the substrate 10.
Are arranged side by side on the longitudinal axis of the. At the same time, the substrate 10
A plurality of cooling water holes (not shown) and a lubricating oil hole (not shown) are bored in this, and a plurality of bolt holes 12 are bored. The stamped substrate 10 is curved along the winding direction of the material 2. That is, in the present embodiment, the material 2 is of a type having a stress that bends inward in the winding direction, and therefore the material 2 is curved in the width direction so that the lower side is the concave side in FIG. Incidentally, instead of processing by the first press device 6,
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 pressing device 7 shown in FIG. A bead 14 is formed on. In this case, the bead 13 is formed so as to project to 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, it is also called a half bead as compared with the bead 13. Although illustration of equipment is omitted in FIG. 1, after the entire substrate 10 is cleaned and subjected to a predetermined heat treatment as necessary, the substrate 10 is conveyed to the coating device 8 where the sealing material is applied to the substrate 10. Are coated, and sealing films 30 are formed on both surfaces of the substrate 10 as shown in FIG.

In the coating device 8, as shown in FIG. 2, a liquid sealing material such as unvulcanized fluorine rubber is sprayed from the supply device 8a to form a sealing film 30 on the surface of the substrate 10. Instead of the spray-type supply device 8a, a coating device (not shown) in which the supply device is provided on the upper side and the housing device is provided on the lower side may be used. In this device, the sealing material is continuously flowed down from the supply device to form a film-shaped lower surface in the vertical direction, and the sealing material flowed down to the accommodation device arranged on the lower side is returned to the supply device.
A film-like bottom surface is always formed. In addition, a pair of conveyors 8c and 8d for conveyance are installed substantially horizontally adjacent to each other. The substrate 10 supplied to the coating apparatus 8 is once inverted so that the protruding surface of the bead 13 faces upward, and is conveyed by the conveyor 8c toward the supplying apparatus 8a. Then, when the substrate 10 passes through the film-shaped lower surface, the sealing material spreads on the surface of the substrate 10 to form a film,
The sealing film 30 is uniformly formed. Incidentally, it goes without saying that a drying operation or a solidifying operation accompanying the coating step may be carried out if necessary.

After the seal film 30 is formed on the surface of the substrate 10 on the protruding side of the bead 13 in this way, the substrate 10 is inverted again and conveyed in the opposite direction, and passes under the supply device 8a. At this time, since the substrate 10 is supported on the conveyors 8c and 8d by both ends, the top surface of the bead 13 does not contact the conveyors 8c and 8d. Thus, FIG.
As shown in FIG. 5, the seal film 30 is also formed on the surface of the substrate 10 opposite to the protruding side of the bead 13. After that, the sealing films 30 formed on both surfaces of the substrate 10 are solidified by vulcanization treatment if necessary. The thickness of the sealing film 30 is
It can be appropriately set by adjusting the amount of the sealing material sprayed from the supply device 8a, the transport speed of the conveyors 8c and 8d, and the like. The substrate 10 may be coated on only one side of the substrate 10 by the above-mentioned spray-type supply device 8a or a device for forming a film-shaped lower surface.

Comparing the defective rate of the seal film 30 in the metal gasket 1 thus formed with the conventional example, in the metal gasket in which the protruding side of the bead 13 is formed on the curved convex side of the substrate 10, it is 20 to 30. While the defect rate was%, in this example, it was reduced to 0.5% or less. In addition, when the metal gasket 1 is conveyed, assembled, or otherwise placed on a conveyor or stacked on another metal gasket, the substrate 10 is supported by both ends, so that the top of the bead 13 is supported. It is prevented that the surface of the substrate 10 including the metal contacts these, and the sealing film 30
No scratches or peeling will occur.

The metal gasket 1 constructed as described above
A fastening bolt (not shown) is inserted, and the bead 13 is arranged so that the projecting side of the bead is on the cylinder block (not shown) side, 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
Adheres to the joint surface of the cylinder block (not shown), and the bead 13 deforms. Then, when the space between the cylinder head and the cylinder block is tightened, the substrate 10 becomes bead 13
It comes into close contact with the cylinder block due to its elastic restoring force. Thus, in the metal gasket 1, a predetermined surface pressure is secured around each combustion chamber hole 11 by the bead 13. Moreover, since the seal film 30 is uniformly formed on the entire surface of the substrate 10 including the beads 13, even if the joint surface of the cylinder head and the cylinder block is rough, the seal film 30 is in close contact with the seal film 30 and good sealing performance can be obtained.

FIGS. 5 to 7 relate to another embodiment of the present invention, in which two substrates 10a and 10b are joined together to form a metal gasket 1a. In the state shown in FIG. Is interposed between. Board 10
Although a and 10b are basically the same as the configuration of the substrate 10 shown in FIGS. 3 and 4, both have an axially asymmetrical shape, and the curved concave side of one substrate 10a and the other substrate 10a. The curved concave sides of 10b are joined so as to face each other. Therefore, as shown in FIG. 6, both end portions in the longitudinal direction of the substrates 10a and 10b come into contact with each other. It should be noted that each reference numeral in FIGS. 5 to 7 is a with respect to each reference numeral in FIGS. 3 and 4 and a is attached to one substrate side and b is attached to the other substrate side.
However, in FIG. 5, the bead 14a is shown by a dashed line.

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

FIG. 8 shows the two substrates 10 shown in FIG.
2 shows the manufacturing process of the metal gasket 1a for joining a and 10b. Two sets of the apparatus shown in FIG.
An assembling machine 9 for joining 0a and 10b is arranged in the final step. Further, a welding machine 9x is arranged in the manufacturing process of the substrate 10a. It should be noted that devices corresponding to the devices shown in FIG. 1 are shown by adding a or b to the reference numerals of the devices in FIG. 1, but these are substantially the same, and the upper part of FIG. 8 shows the substrate 10a. Showing the process of manufacturing the substrate, the lower stage being the substrate 10b
7 shows a process for manufacturing. In particular, the upper first press device 6a and the lower first press device 6b have the same die shape.

As is clear by comparing the above two steps,
The upper material 2a is supported by the supporting 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 supporting device 3b so as to be pulled out from below the coil. ing. That is, the feeder 5
The material 2b supplied from b to the first press device 6b is
Since the material has the same relationship as the material 2a is wound in the opposite direction, and the first press devices 6a and 6b have the same cutting die, the substrate 10a conveyed to the second press device 7a. The curved recess is located below, while the second
The curved recess is located above the substrate 10b conveyed to the pressing device 7b. Therefore, in the second pressing device 7b, the bead 13b is formed so as to project upward in the same direction as the curved concave portion of the substrate 10b. For this reason,
In the pressing device 7b, the mold for forming the bead 13b is provided so that the bead forming direction is upside down from that of the upper second pressing device 7a.

A welding machine 9x, for example, a pulse-driven laser welding machine is provided in the upper step, and the substrate 10 on which the bead 13a is formed by the second press device 7a.
a is inverted, and the shim ring 20 is welded substantially continuously around the combustion chamber hole 11a so that the curved concave portion is located upward. Therefore, the substrate 10a is not turned over, is washed as it is, is heat-treated if necessary, and is then conveyed to the coating device 8a, and the sealing film 30 is sequentially formed from the protruding side surface of the bead 13a.

Thus, the substrates 10a and 10b are respectively coated with the sealing films 30a and 30b through the coating devices 8a and 8b.
After the formation, the assembling machine 9 is assembled so that the curved concave portions face each other as shown in FIGS. 5 and 6, and although not shown in FIGS. 5 to 7, the substrates 10a and 10b are not shown.
The ends are joined by caulking. Incidentally, as means for joining the ends of the substrates 10a and 10b in the assembly machine 9,
In addition to caulking, welding or adhesion may be used.

The material 2b supported by the supporting device 3b
May be arranged so as to be pulled out from above similarly to the material 2a, but in this case, the cutting die of the first pressing device 6b in the lower stage of FIG. 8 is changed to the cutting die of the first pressing device 6a in the upper stage. On the other hand, it is necessary to form the substrate 10a so as to be symmetrical about the axis thereof. Also, regarding the bead forming die of the second pressing device 7b, even if the bead forming direction is the same as that of the second pressing device 7a, the forming position of the bead 13b may be the forming position of the bead 13a depending on the shapes of the substrates 10a and 10b. Since it is different in the width direction, it is necessary to form the mold so that the bead 13b is formed at a predetermined position. The substrate 1
The sealing film 30 may not be formed on the entire surface 0b or on the protruding surface of the bead 13b.

Then, the metal gasket 1a is interposed between the cylinder head and the cylinder block, and a tightening force is applied, and 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. At this point, 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, which is effective when the substrate is formed in a flat plate shape without being curved. That is, a plurality of tongue-shaped support portions 15c are bent and formed on the outer peripheral end of the flat plate-shaped substrate 10c so as to extend in the same direction as the bead protruding direction (downward in FIG. 9). The height of the supporting portion 15c from the substrate 10c is set to be larger than the height of the bead. Thus, in this embodiment, the supporting portion 15c
As shown in FIG. 9, 2 are arranged on each side of the substrate 10c in the longitudinal direction.
And one each in the width direction. According to the present embodiment, even if the substrate 10c is a flat plate, it is possible to avoid the top of the bead from coming into contact with the conveyor or the like. The support portion 15
Since c is provided on the outer peripheral end of the substrate 10c and outside the range of the joint surface between the cylinder head and the cylinder block, it is not sandwiched between the two.

FIG. 10 shows another embodiment of a metal gasket manufactured by another manufacturing method of the present invention, in which a support portion 15c extending to the bead protruding side of the substrate 10c (downward in FIG. 10) is provided. In addition, the support portion 16c extending to the opposite side (upper side in FIG. 10) to the protruding side of the bead is formed by bending. According to this embodiment, the substrate 10
It is possible to protect the entire seal film uniformly formed on both surfaces of c. In any of the embodiments shown in FIGS. 9 and 10, the support portions 15c and 16c are formed integrally with the substrate 10c, but they may be formed separately and a resin member, for example, may be adhered thereto. In addition, the support portions 15c and 16
The length, number, and position of c are not limited to those in the above embodiment,
It can be appropriately set depending on the situation such as manufacturing, transportation, and assembly.

[0031]

Since the present invention is configured as described above, it has the following effects. That is, according to the method for manufacturing a metal gasket of the present invention, the substrate is formed to be curved and the bead is formed so as to protrude toward the curved concave portion of the substrate, or the bead height is increased at the outer peripheral end of the substrate. Since a larger supporting portion is provided, it is possible to prevent scratches and peeling of the seal film formed on the bead protruding side of the substrate during manufacturing, transportation, assembly, etc. It is possible to secure the sex.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing details of the coating apparatus in FIG.

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

4 is a cross-sectional view taken along the line AA of FIG.

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.

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

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 the metal gasket manufactured by the 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 Assembly 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 Supporting part 20 Shim ring 30, 30a, 30b Seal film

Claims (3)

[Claims] 1. A substrate is provided with a fluid hole through which a pressure fluid passes, a bead is formed to project around the fluid hole, and a sealing 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, a rolled rolled metal plate is punched into a predetermined shape to form the substrate, and the bead is curved with respect to the substrate curved along the winding direction of the rolled metal plate. A method for manufacturing a metal gasket, characterized in that the metal gasket is formed so as to protrude toward the recess. 2. A rolled rolled metal plate is punched into a predetermined shape to form a pair of substrates that are curved along the winding direction of the rolled metal plate, and a pressure 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 project toward the curved concave side of each of the pair of substrates, and at least one of the pair of substrates has at least the bead. A method of manufacturing a metal gasket, comprising forming a seal film on a surface including a protruding side of the substrate, and joining the pair of substrates so that the beads are opposed to each other to form a metal gasket. 3. A substrate is formed with a fluid hole through which a pressure fluid passes, a bead is formed around the fluid hole, and a sealing film is formed on the surface of the substrate including at least the protruding 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 to a protruding side of the bead to form a support part having a height higher than a height of the bead. And a method of manufacturing a metal gasket.