JPH1068465A - Manufacture of metallic gasket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a metallic gasket material in a simple process by forming a bead around a part of gasket holes after gasket holes are made in a metallic sheet, partly applying the organic polymer paint in the desired part of the metallic sheet, and cross-linking the applied organic polymer layer. SOLUTION: In manufacturing a metallic gasket, a large number of necessary gasket holes are punched in a long metallic sheet to be fed from a feed drum so as to be immediately adapted to the predetermined acquired design. The paint is partially applied to each side of the periphery of the whole or a part of the gasket holes, e.g. combustion chamber holes B1, and the paint is dried or cross-linked as necessary. After a cross-linked rubber layer is formed on each side of the metallic sheet, a bead P is formed on the periphery of the gasket holes having the cross-linked rubber layer. Heat resistant rubber, e.g. fluoro rubber is used for the organic polymer which is the major composition of the paint when the metallic gasket is used for the cylinder head gasket or its parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing various metal gaskets, particularly cylinder gaskets for automobile engines or metal gaskets used as parts thereof.

[0002]

2. Description of the Related Art FIG. 1 is a plan view of a typical metal cylinder head gasket (hereinafter, CHG) of an automobile engine, and FIG. 2 is a cross-sectional view taken along a line XX of FIG.
CHG is composed of two stainless steel plates 1 having a flat stainless steel plate 2 having a swelling portion (hereinafter, bead) P.
A number of gasket holes penetrating the three-layer structure, that is, a combustion chamber hole B1, a bolt hole B2, and other holes are formed. There are water holes and oil holes as other holes, but these holes are not shown in FIG. 1 to avoid complication of the figure. In many cases, the stainless steel plate 1 has a bead P around each gasket hole, for example, the combustion chamber hole B1, and layers R1 and R2 of heat-resistant rubber such as fluororubber on both surfaces of the bead P and its vicinity. Are formed. The bead P and the rubber layers R1 and R2 function to enhance the sealing function of CHG. CHG may be composed of a single stainless steel plate 1 or a two-layer structure of one stainless steel plate 1 and a stainless steel plate 2.

In any case, CHG is a stainless steel plate 1
Conventionally, the steel plate body has been manufactured through the following extremely complicated steps. That is, FIG. 1 shows a step 1 of drilling a combustion chamber hole B1, a bolt hole B2, and other gasket holes in a long stainless steel sheet of a raw material, a step 2 of forming a bead P around each gasket hole, and a long stainless steel sheet. Step 3 of punching a stainless steel plate 1 having such a shape, Step 4 of applying and drying a heat-resistant rubber paint to form a heat-resistant rubber layer R1, and Heat-resistant rubber to form a heat-resistant rubber layer R2. The first step 5 in which the paint is applied and dried, the step 6 in which the same action as in the step 5 is repeated, and the step 7 in which the dried heat-resistant rubber layers R1 and R2 are crosslinked. It is extremely difficult to form the heat-resistant rubber layers R1 and R2 to a uniform thickness inside and outside a curved surface portion such as a bead P in a plate made of an iron-based metal such as stainless steel. The reason for this is that, unlike the flat portion of the plate, the curved surface portion has poor applicability of the heat-resistant rubber paint, and the degree of difficulty in applying the paint is different inside and outside the curved surface portion. For this reason, the inner surface (concave surface) and the outer surface (convex surface) of the curved surface portion are separately applied with special care in a separate step, and the outer surface (convex surface) having particularly poor applicability is applied twice. To ensure the required coating thickness.

[0004]

An object of the present invention is to provide a method for manufacturing a metal gasket material having a heat-resistant rubber layer on both sides of a bead portion, such as the above-mentioned stainless steel plate body 1, by a simpler process. It is to propose.

[0005]

The present invention has the following features. 1. A hole forming step for forming a gasket hole in a metal sheet, a bead forming step for forming a bead around at least a part of the gasket hole, a partial applying step for partially applying an organic polymer paint to a desired portion of the metal sheet, and applying A method for producing a metal gasket material, comprising: a cross-linking step of cross-linking the formed organic polymer layer; and performing the partial coating step before the bead forming step. 2. 2. The method for producing a metal gasket material according to 1 above, wherein the perforating step is performed before the partial coating step. 3. 2. The method for producing a metal gasket material according to 1 above, wherein the perforating step is performed after the partial coating step. 4. 4. The method for producing a metal gasket material according to any one of the above items 1 to 3, further comprising a step of drying and / or pre-crosslinking the partially applied paint between the partial application step and the crosslinking step. 5. The method for producing a metal gasket material according to any one of the above items 1 to 4, wherein the metal sheet is a steel sheet. 6. The above 1-4, wherein the organic polymer coating is a heat-resistant rubber coating.
The method for producing a metal gasket material according to any one of the above. 7. 7. The metal according to any one of 1 to 6, wherein the metal gasket material is a cylinder head gasket of an automobile engine, at least a part of the gasket hole is a combustion chamber hole, and a partial application portion is around the combustion chamber hole. Manufacturing method of gasket material.

[0006]

The organic polymer coating is applied to the metal sheet before forming the bead, that is, at a stage where the metal sheet is still flat, so that it can be easily applied partially and uniformly. Organic polymers, especially heat-resistant rubber coatings, are expensive, but according to the invention the formation of the organic polymer layer can often be achieved with a single application, which is extremely economical. It is. Further, for example, by performing the above-described four steps successively and continuously on a metal sheet that is continuously running, the metal gasket material can be manufactured more stably and economically.

[0007]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a metal gasket material is formed by a drilling step, a bead forming step, a partial coating step,
And a cross-linking step. Of these four steps, the partial coating step can be performed in various orders as long as it is performed at least before the bead forming step. For example, a drilling step, a partial coating step, a crosslinking step, a bead forming step, a partial coating step, a crosslinking step, a drilling step, a bead forming step, or a partial coating step, a drilling step, a crosslinking step, a bead forming step. The order of the steps, etc.

[0008] As the metal sheet as the object to be coated, a sheet made of various metals, for example, iron-based metals, aluminum, copper, nickel or other metals can be used.
The metal gasket material to be manufactured is CHG as shown in FIG.
Alternatively, in the case of the component, the constituent metal of the sheet is preferably a heat-resistant metal, particularly an iron-based metal. Examples of iron-based metals include Fe-C alloys, ferritic stainless steels, martensitic stainless steels, stainless steels such as austenitic stainless steels, ferromanganese, ferrosilicon, ferronickel, ferrochrome or other,
Ferroalloys based on iron, in particular with an iron content of at least 80% by weight. Among such iron alloy sheets, stainless steel sheets, particularly SUS301-CS
P, SUS304-CSP, SUS420J2-CS
P, stainless steel strip for springs such as SUS631-CSP is preferred. The thickness of the metal sheet is 0.05-1 mm,
In particular, 0.1 to 0.5 mm is appropriate.

In the case where a continuous long metal sheet is used as a raw material, as an example, a stainless steel plate shown in FIGS. 1 and 2 is formed in the order of a punching step, a partial coating step, a crosslinking step, and a bead forming step. 1 will be described in detail. In this case, in any of the above four steps,
Alternatively, after the final bead forming step, a large number of pieces of the stainless steel sheet 1 are punched out of the continuous metal sheet. Usually, the punching residue is minimized. The acquisition design of the pieces is first determined so as to punch through the maximum number of pieces of the stainless steel plate 1. The long metal sheet supplied from the delivery drum continuously travels through the punching step, the partial coating step, the cross-linking step, and the bead forming step sequentially, and obtains the above-mentioned predetermined value in the punching step. First, a number of necessary gasket holes are punched to respond to the design. The coating is then applied separately or simultaneously to all or part of the gasket holes, e.g. to the combustion chamber holes, separately or simultaneously, and the applied coating is crosslinked after drying or precrosslinking as required. . After the crosslinked rubber layers are formed on both sides of the metal sheet, beads are formed around the gasket holes having the crosslinked rubber layers. When it is necessary to perform a perforation step before the crosslinking step after the partial application step, in order to prevent the deformation of the paint applied by various external forces at the time of the perforation step, drying of the above-described paint or More pre-crosslinking is required.

In the case where the partial coating step is performed on the long continuous metal sheet before the drilling step, the coating is partially or separately applied to both surfaces around a predetermined punching position of the gasket hole separately or simultaneously. The paint applied in accordance with the above is dried and then crosslinked to form a crosslinked rubber layer, and then a punching step and a subsequent bead forming step are performed.

In the continuous process using a long continuous metal sheet, the position of the gasket hole to be punched and the position of the partial application of the paint are determined by forming appropriate standard marks attached to the metal sheet in advance. By using a punching machine equipped with an image pickup device, the standard landmark can be caught every time before the start of punching and can be determined instantaneously. If the hole to be punched and the position of the partial coating can be determined instantaneously as described above, such as between the drilling process and the subsequent partial coating process, or between the crosslinking process and the subsequent drilling process, etc. The line speed of the metal sheet can be adjusted freely by installing a dancer roll on the metal sheet.

Both surfaces of the metal sheet to be coated are subjected to a cleaning treatment by a usual method before the partial coating step, and then a surface treatment is preferably performed using a normal primer such as a silane coupling agent. Partial application of paint to metal sheet
It may be coated by dispenser coating, screen coating, roll coating, or other methods.

Various organic polymers can be employed as the organic polymer as the main component of the paint, depending on the use of the metal gasket material to be manufactured. For example, when the metal gasket material is CHG as shown in FIG. 1 or a part thereof, heat-resistant rubber such as fluorine rubber, silicon rubber, acrylonitrile-butadiene rubber, or the like is preferable. As the heat-resistant rubber, a paint dissolved in a solvent having a good affinity for each rubber is used.

The paint partially applied on the metal sheet is then subjected to a crosslinking step, but before that, it is dried or pre-crosslinked as required. Drying and pre-crosslinking are generally preferred treatments because they can avoid the foaming phenomenon in the crosslinking step due to the remaining solvent or evaporable substances such as moisture. Crosslinking of the partially applied paint layer is performed by heat crosslinking, electron beam irradiation crosslinking, ultraviolet irradiation crosslinking, or other crosslinking methods depending on the type of organic polymer used and the type of crosslinking agent and the like.

The long metal sheet that has been subjected to the three steps of the punching step, the partial coating step, and the cross-linking step has a large number of gasket holes, and ring-shaped or other various types formed on both surfaces around the gasket holes. It has a shaped crosslinked organic polymer layer. As described above, the bead forming step may be performed on a continuous long metal sheet, or after punching a large number of pieces of the stainless steel plate 1 from the long metal sheet, May go. In any case, the bead can be formed by a conventionally known apparatus and method.

In the present invention, the metal sheet as the raw material to be coated with the coating material may be applied in the form of a long continuous body as described above, or may be a flat piece previously punched into the shape of the final metal gasket material. Good. The details of manufacturing the stainless steel sheet 1 shown in FIGS. 1 and 2 in the order of the punching step, the partial coating step, the cross-linking step, and the bead forming step for the flat plate piece will be described. First, a required gasket hole is punched in each of the flat plate pieces of the raw material to be sent. Then, paint is applied separately or simultaneously on both sides around the gasket hole separately, and if necessary, the applied paint is dried or pre-crosslinked to form a crosslinked rubber layer that has been crosslinked later. Forming a bead around the gasket hole having

In the case where the partial coating step is performed on the flat plate piece of the raw material before the punching step, the coating is applied separately or simultaneously to both surfaces around the predetermined position where the gasket hole is to be punched, and the coating is performed as necessary. The paint thus obtained is dried or pre-crosslinked, and then crosslinked to form a crosslinked rubber layer, followed by a punching step and a subsequent bead forming step.

[0018]

The present invention will be described in more detail with reference to the following examples.

Example 1 SUS301-CSP having a thickness of 0.25 mm and a width of 40 cm
A 3 / 4H SUS sheet is continuously fed horizontally from the take-up roll, and sequentially passed through a washing tank, a primer tank filled with a silane coupling-type primer (Chemloc, a product of Lord Far East Co., USA), and a drying chamber. A primer layer was formed on both sides of the substrate. Subsequently, one side of the SUS sheet was partially coated with a fluororubber paint to be described later around a position where various gasket holes were to be punched by a screen coater, and the applied layers were dried. Then, the SUS sheet was U-turned, and the remaining surface was partially coated with the same pattern of fluororubber paint in exactly the same manner as the one surface, and the applied layers were dried. Subsequently, the SUS sheet was passed through an oven at about 200 ° C. to heat and crosslink the fluororubber coating layers on both surfaces thereof. The SUS sheet was finally passed through a punch, a beater, and a CHG puncher sequentially through a line speed adjustment process using a dancer roll. Thus about 36cm in length and about 15c in width
Continuous production of CHG material having the same structure as the stainless steel plate 1 shown in FIGS. 1 and 2 having 3 combustion chamber holes, 8 bolt holes, 21 water holes, and 6 oil holes in the center. did. The fluororubber paint used in this example was fluororubber (Viton, trade name, manufactured by DuPont, USA),
5 parts by weight of bisphenol crosslinking agent per part by weight, 20 parts by weight
Parts by weight of carbon black (MT), 3 parts by weight of Mg
A rubber composition comprising O and 6 parts by weight of Ca (0H) ₂ is dissolved in methyl ethyl ketone to obtain a fluororubber concentration of 40% by weight. Thus, CHG having a crosslinked fluororubber layer of uniform thickness on both sides of the beet could be produced.

Example 2 A SUS sheet having a primer layer formed on both sides of a clean surface was subjected to the necessary perforation before partial coating was performed.
The same material for CHG as in Example 1 was continuously produced.

[0021]

After the bead forming step, it is extremely difficult to uniformly coat both the inner and outer surfaces of the bead with a heat-resistant rubber coating, and therefore, the production of CHG materials and the like is conventionally complicated. Although multiple steps were required, in the present invention, the metal sheet before bead formation is still flat at the stage where the metal sheet is still flat, so that both sides of the metal sheet are simultaneously applied to only necessary portions, so that uniform application can be easily performed. . As a result, the production process is greatly simplified and, in addition, all processes can be made continuous. By continuity of all the processes, it is possible to produce a CHG material having more stable quality and at a low cost. In addition, generally expensive heat-resistant rubber paint,
The present invention greatly contributes to low-cost production of CHG materials and the like, since the invention is applied only to necessary parts.

[Brief description of the drawings]

FIG. 1 is a plan view of a typical metal cylinder head gasket of an automobile engine.

FIG. 2 is a sectional view taken along the line XX of FIG.

[Explanation of symbols]

 1, 2 stainless steel plate P bead B1 combustion chamber hole B2 bolt hole R1, R2 heat resistant rubber layer

Claims (7)

[Claims] 1. A step of forming a gasket hole in a metal sheet, a bead forming step of forming a bead around at least a part of the gasket hole, and a step of partially applying an organic polymer paint to a desired portion of the metal sheet. A method for producing a metal gasket material, comprising: a coating step; and a crosslinking step of crosslinking the applied organic polymer layer, wherein the partial coating step is performed before the bead forming step. 2. The method for producing a metal gasket material according to claim 1, wherein the drilling step is performed before the partial coating step. 3. The method for producing a metal gasket material according to claim 1, wherein the drilling step is performed after the partial coating step. 4. The method for producing a metal gasket material according to claim 1, further comprising a step of drying and / or pre-crosslinking the partially applied paint between the partial application step and the crosslinking step. 5. The metal sheet is a steel sheet.
5. The method for producing a metal gasket material according to any one of items 4. 6. The method for producing a metal gasket material according to claim 1, wherein the organic polymer coating is a heat-resistant rubber coating. 7. The gasket material according to claim 1, wherein the metal gasket material is a cylinder head gasket of an automobile engine, at least a part of the gasket hole is a combustion chamber hole, and a partial application portion is around the combustion chamber hole. A method for producing a metal gasket material according to any one of the above.