JP2543810B2 - Valve plate for lead valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve plate for a reed valve used for controlling intake and exhaust of an internal combustion engine or the like.

[0002]

2. Description of the Related Art As a valve plate for a reed valve used for controlling intake and exhaust of an internal combustion engine, particularly a two-cycle engine, a valve plate made of a steel thin plate, a glass fiber reinforced resin or a carbon fiber reinforced resin is conventionally used. Since the valve plate made of fiber reinforced resin has excellent high-speed response, it is an essential material for races. Tokuhei 3-7
No. 5033 discloses a reed valve valve plate made of a fiber-reinforced epoxy resin molding containing butadiene-acrylonitrile having a carboxyl group at both ends in a resin. This has flexibility and thereby has improved use durability. In recent years, due to the high performance of the engine, the valve plate for a reed valve has also been required to have high durability, but the known ones described above still have unsatisfactory use durability. .

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a valve plate for a reed valve, which is made of a fiber-reinforced resin having excellent durability.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to solve the above problems, and as a result, in a reed valve valve plate made of a cured product of a fiber-reinforced epoxy resin, an epoxy resin composition containing a specific amount of a phenoxy resin. The inventors have found that a thermosetting product of a material and a reinforcing fiber is very excellent in durability, and have completed the present invention. That is, according to the present invention, for a reed valve, which comprises a thermosetting epoxy resin composition containing (A) a phenoxy resin in an amount of 2 to 10% by weight based on the total amount of the composition, and (B) a reinforcing fiber. A valve plate is provided.

The thermosetting epoxy resin composition used for the valve plate for a reed valve of the present invention contains an epoxy resin, a phenoxy resin and a curing agent, and the content of the phenoxy resin is 2 to 10 relative to the composition. It is in the range of% by weight. When the content of the phenoxy resin is less than this range, the durability is poor, and when it is more than the above range, the molded product is warped, which is not preferable.

The epoxy resin used in the present invention is not particularly limited, and bisphenol A type epoxy resin, glycidyl amine type epoxy resin, novolac type epoxy resin, urethane modified bisphenol A type epoxy resin, alicyclic epoxy resin and the like are used. , Bisphenol A epoxy resin, glycidyl amine epoxy resin,
Novolak-based epoxy resins are preferred, and these epoxy resins may be used alone, but use of a combination of a bisphenol A-based epoxy resin and a glycidyl amine-based epoxy resin and a combination of a bisphenol A-based epoxy resin and a novolac-based epoxy resin Is especially excellent in terms of durability.

The phenoxy resin used in the present invention is a linear polymer compound represented by the following formula: bisphenol A
And epichlorohydrin are reacted in equimolar amounts.

[0008]

Embedded image

In the above formula, Ph represents a phenylene group, and n
Is 50 or more, preferably 70 to 160. Such phenoxy resin is already commercially available, for example,
E-1255 (made by Yuka Shell Epoxy Co., Ltd.), YP-50
(Manufactured by Toto Kasei Co., Ltd.) and the like, and those dissolved in a solvent are preferably used.

The curing agent is not particularly limited as long as it is for curing an epoxy resin, but imidazole, dicyandiamide, a urea compound and a mixture thereof are preferable in terms of curing time and storage stability of prepreg. Can be used.

Examples of the reinforcing fibers used in the present invention include inorganic fibers such as carbon fibers and glass fibers, aramid fibers, organic fibers such as wholly aromatic polyester fibers, and high-density polyethylene ultra-stretched fibers. Glass fibers are preferred.

An example of a suitable method for producing the thermosetting epoxy resin composition used in the present invention will be explained. First, a solution prepared by dissolving an epoxy resin in a solvent is added to a solution prepared by dissolving a phenoxy resin in the solvent. Mix. Next, a solution in which a curing agent is also dissolved in a solvent is added to and mixed with the mixed resin solution. Thus, the thermosetting epoxy resin composition for fiber impregnation is manufactured.

Next, one example of the method for producing a reed valve valve plate according to the present invention will be described. First, a thermosetting epoxy resin composition is prepared as described above, and then this composition is added to the reinforcing fiber. After impregnation, drying at a temperature of 80 to 130 ° C. and semi-curing to prepare a prepreg sheet, a plurality of prepreg sheets are laminated and pressed with a press,
Heat-cured at a temperature of 120-150 ° C to a thickness of 0.25
A laminated plate having a thickness of about 0.5 mm is formed, and then the laminated plate is cut or punched to produce a valve plate for a reed valve having a desired shape.

The form of the reinforcing fibers used in the production of the prepreg sheet includes those arranged in one direction, flat fiber products, satin fiber products, nonwoven fabrics, etc., but in the present invention, sheets are formed in one direction. It is preferable to prepare a laminate by combining a prepreg sheet formed by arranging the prepreg sheets with a prepreg sheet formed by a plain woven fabric, a satin woven fabric, a non-woven fabric, or the like. When a sheet in which fibers are arranged in one direction is used, it is desirable to arrange the fibers so that the fibers are oriented in the AA direction shown in FIG. Further, in the case of obtaining a thinner valve plate for a reed valve, prepreg sheets in which fibers are arranged in a sheet shape in one direction are laminated in the same direction or alternately orthogonally, or a plain woven fabric, a satin woven fabric, or a non-woven fabric is used. It is advisable to reduce the number of laminated prepreg sheets included. The content of reinforcing fibers in the prepreg sheet is usually 4
It is selected in the range of 0 to 70% by volume, preferably 50 to 65% by volume. The valve plate thus obtained is used by being attached to a reed valve of, for example, a two-cycle gasoline engine.

[0015]

The valve plate for a reed valve of the present invention is made of a fiber reinforced plastic and uses a curable epoxy resin composition containing a specific amount of a phenoxy resin as a matrix resin. It has excellent affinity and adhesiveness with the fibers for use, and has high practical value with improved durability in use as compared with conventional products without impairing the responsiveness of the engine at high speed operation. Also, minute cracks are less likely to occur during punching or cutting in the valve plate manufacturing process, which also contributes to improvement in use durability of the valve plate.

[0016]

【Example】

Example 1 (1) A solution of 5 parts by weight of a phenoxy resin having a molecular weight of 36000 in a mixed solvent of cyclohexanone and xylene was added to a methyl ethyl ketone solution containing 100 parts by weight of a bisphenol A epoxy resin having an epoxy equivalent of 600, and bisphenol A was added. An epoxy base resin composed of epoxy resin and phenoxy resin was manufactured. (2) A mixed solvent consisting of 4 parts by weight of dicyandiamide (DICY) and 2 parts by weight of aromatic dimethylurea (DMU) (molecular weight: 264) as a promoter, and methanol, propylene glycol monomethyl ether and methyl ethyl ketone. To prepare a hardener solution. (3) The total amount of the epoxy main agent solution of (1) and the total amount of the curing agent solution of (2) were mixed by stirring to prepare a prepreg solution having a solid content concentration of 45%. (4) Next, this solution was unidirectionally arrayed with carbon fibers (tensile strength: 3700 MPa, tensile elastic modulus: 235 GP
a, elongation: 1.6%), and then dried and semi-cured at 125 ° C. to prepare a prepreg sheet having a resin content of 40% by volume. Further, a plain woven fabric of the same carbon fiber was used to prepare a prepreg sheet having a resin content of 40% by volume in the same manner as described above. (5) Then, as shown in FIG. 2, a prepreg sheet in which carbon fibers are unidirectionally arranged is interposed between two carbon fiber plain woven prepreg sheets to form three layers, which are heat-cured at 130 ° C., A laminated plate having a thickness of 0.4 mm was produced. This laminated plate was punched out to produce a reed valve valve plate as shown in FIG. No cracks were found on this valve plate.

The valve plate was then tested as follows. By installing valves on the intake side and exhaust side, and reciprocating a cylinder whose intake and exhaust amounts can be changed about 3,300 times per minute, air is applied as a load to the reed valve valve plate for a total of 10,000,000 times. Even when the reed valve valve plate was opened and closed, the maximum exhaust amount (liter) at which the valve plate was not damaged was measured, and the exhaust amount was taken as the durability value. The results are shown in Table 1.
Shown in

Example 2 50 parts by weight of the bisphenol A epoxy resin of Example 1 and phenol novolac epoxy resin Epicoat 15
4 (manufactured by Yuka Shell Epoxy Co., Ltd.) was added to a solution containing 5 parts by weight of the phenoxy resin of Example 1 in 50 parts by weight of a methyl ethyl ketone solution, and the mixture was stirred with bisphenol A epoxy resin, phenol novolac epoxy resin and phenoxy resin The following epoxy base compound was produced. To the total amount of this epoxy main agent, the total amount of the curing agent solution of Example 1 was added,
A prepreg solution having a solid content concentration of 50% was prepared. next,
Using this prepreg solution, a unidirectional and plain woven prepreg sheet was produced in the same manner as in Example 1, and a reed valve valve plate was produced by press molding. The characteristics of this are shown in Table 1.

Example 3 To a methyl ethyl ketone solution containing 50 parts by weight of the bisphenol A epoxy resin of Example 1, a tetrafunctional glycidylamine type epoxy resin having an epoxy equivalent of 119 heated to 80 ° C. (Epicoat 604, Yuka Shell Epoxy Co., Ltd.) was used. Made)
50 parts by weight was gradually added with stirring to completely dissolve it. A solution containing 5 parts by weight of the phenoxy resin of Example 1 was added to the total amount of this mixed solution, and the mixture was stirred with stirring to produce an epoxy main agent composed of a bisphenol A epoxy resin, a glycidyl amine type epoxy resin and a phenoxy resin. The total amount of the curing agent solution of Example 1 was added to the total amount of this epoxy main agent to prepare a prepreg solution having a solid content concentration of 50%. Next, using this prepreg solution, a unidirectional and plain woven prepreg sheet was prepared in the same manner as in Example 1, and a reed valve valve plate was manufactured by press molding. The characteristics of this product are shown in Table 1.
Shown in

Example 4 Unidirectional carbon fibers having a tensile strength of 4800 MPa, a tensile modulus of 230 GPa and an elongation of 2.1% were used.
A reed valve valve plate was produced in the same manner as in Example 3. The characteristics of this are shown in Table 1.

Comparative Example 1 A reed valve valve plate was produced in the same manner as in Example 1 except that the phenoxy resin was not added. The characteristics of this product are shown in Table 1.
Shown in

Comparative Example 2 A reed valve valve plate was produced in the same manner as in Example 1 except that the amount of phenoxy resin was increased to 15 parts by weight. The characteristics of this are shown in Table 1.

Comparative Example 3 A reed valve valve plate was produced in the same manner as in Example 2 except that the amount of phenoxy resin was increased to 15 parts by weight. The characteristics of this are shown in Table 1.

Comparative Example 4 75 parts by weight of a bisphenol A epoxy resin having an epoxy equivalent of 190 (manufactured by Epicoat 828 Yuka Shell Epoxy Co., Ltd.) and a bisphenol A epoxy resin having an epoxy equivalent of 450 (Epicoat 1001 manufactured by Yuka Shell Epoxy Co.) Hiker CTBN1300 with 10 parts by weight, phenol novolac epoxy resin (Epicoat 154 manufactured by Yuka Shell Epoxy Co., Ltd.), and carboxyl equivalent of about 1500
A reaction product of X9 (manufactured by the BF Goodrich Chemical Company) with 5 parts by weight of Epicoat 828 having an epoxy equivalent of 190 and 5 parts by weight of 2-ethyl-3-cyanoethyl-4-methylimidazole were dissolved in methyl ethyl ketone. .
It has a carboxyl group at both ends. A 40% prepreg solution of a curable epoxy resin composition containing 10% by weight of a butadiene-acrylonitrile copolymer was prepared. Next, using this prepreg solution, a unidirectional and plain weave prepreg sheet was prepared in the same manner as in Example 1, and a reed valve valve plate was produced by press molding. The characteristics of this are shown in Table 1.

[0023]

[Table 1]

[Brief description of drawings]

FIG. 1 shows a plan view of an example of a valve plate for a reed valve according to the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

[Explanation of reference numerals] 1 valve plate for reed valve 2 opening for fixing 3 sheet part in which carbon fibers are arranged in one direction 4 carbon fiber plain woven sheet part

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical display location // C08L 63:00 (72) Inventor Otozu Okuto 4-11-2 Ginza, Chuo-ku, Tokyo Somer Co., Ltd. (72) Inventor Kikuo Watanabe 4-11-2 Ginza, Chuo-ku, Tokyo Somer Co. Ltd. (72) Inventor Ichiro Akutagawa 4-11-2 Ginza, Chuo-ku, Tokyo Somer (56) References JP-A-4-234440 (JP, A) JP-B 3-75033 (JP, B2)

Claims (4)

(57) [Claims] 1. A reed valve valve plate comprising a thermosetting epoxy resin composition containing (A) a phenoxy resin in an amount of 2 to 10% by weight based on the total amount of the composition, and (B) a reinforcing fiber. 2. The valve plate for a reed valve according to claim 1, wherein the thermosetting epoxy resin composition contains a bisphenol A epoxy, a novolac epoxy, and a phenoxy resin. 3. The valve plate for a reed valve according to claim 1, wherein the thermosetting epoxy resin composition contains a bisphenol A epoxy, a glycidyl amine epoxy resin, and a phenoxy resin. 4. The valve plate for a reed valve according to claim 1, wherein the reinforcing fiber is carbon fiber having an elongation of 2% or more.