JP2007196684A - Propeller shaft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a propeller shaft which has such an excellent thermal stability that a mechanical property hardly decreases even in use at a temperature exceeding 150°C. <P>SOLUTION: The propeller shaft having a main body tube and a joint mounted on each of both ends of the main body tube is characterized in that the main body tube is composed of a fiber-reinforced plastic made by reinforcing a thermosetting resin with a reinforcing fiber, and the inequality of T2/T1≥0.83 is satisfied wherein T1 is static torsion strength of the fiber-reinforced plastic under an environment at 25°C, and T2 is the static torsion strength under environment at 150°C. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an FRP propeller shaft (propulsion shaft) used as a driving force transmission shaft of an automobile or the like.

  Conventionally, propeller shafts for automobiles are mostly made of metal, but in recent years, fiber reinforced plastics (FRP) made by reinforcing thermosetting resin with reinforcing fibers for the purpose of reducing vehicle weight and improving fuel efficiency. ) Are being considered.

  As is well known, such an FRP propeller shaft is constructed by attaching metal joints for transmitting torque by connecting to a drive shaft and a driven shaft at both ends of a main body tube made of FRP. Has been.

  By the way, although the propeller shaft of an automobile is disposed under the floor of the vehicle body, it is exposed to a temperature environment of about −40 ° C. to 120 ° C. during use due to natural conditions, heat radiation from an exhaust pipe, a catalyst device, and the like. Therefore, it is required that mechanical properties such as torsional strength and torsional rigidity are not greatly reduced even under such temperatures.

  Now, conventional FRP propeller shafts usually use a body cylinder molded by the well-known filament winding method using a bisphenol A type epoxy resin and an acid anhydride curing agent having a molecular weight of about 300 to 400 as a thermosetting resin. (For example, refer to Patent Document 1).

  Such a bisphenol A type epoxy resin has a viscosity of 5 to 15 poise at normal temperature and a pot life of 6 hours or more, so that it is easy to handle and easy to apply the filament winding method. Since the resin has a glass transition temperature (Tg) of about 120 to 150 ° C., the propeller shaft that forms the main body cylinder with this has a torsional strength, a torsional rigidity, etc. when used in a high temperature environment exceeding 120 ° C. There was a problem that the mechanical properties of the material greatly deteriorated. In addition, with the recent increase in engine output, the temperature around the floor tends to rise, and higher heat resistance is required than before.

In addition, the space around the under floor of the vehicle is limited, and the design that minimizes the distance from high temperature members such as exhaust pipes and catalyst devices is becoming mainstream, and some parts of the prop shaft body etc. are locally The possibility of exposure to high temperatures is high, and from this viewpoint, the heat resistance of the FRP propeller shaft is expected to be improved.
JP 7-208445 A

  In view of the above-described problems of the conventional FRP propeller shaft, the present invention is to provide a propeller shaft that has excellent heat resistance and extremely little deterioration in mechanical properties even when used at temperatures exceeding 150 ° C. Is.

  The present invention employs the following means in order to solve such problems. That is, the propeller shaft of the present invention is a propeller shaft having a main body cylinder and joints attached to both ends of the main body cylinder, and the main body cylinder is a fiber reinforced product obtained by reinforcing a thermosetting resin with a reinforcing fiber. T2 / T1 ≧ 0.83 when the static torsional strength of the fiber reinforced plastic in a 25 ° C environment is T1, and the static torsional strength in a 150 ° C environment is T2. It is characterized by.

Moreover, as a preferable aspect of the propeller shaft of the present invention,
It is mentioned that the said thermosetting resin is comprised with the resin composition containing 30 weight part or more and less than 70 weight part trifunctional or more epoxy resin in 100 weight part of all the epoxy resins.

  Furthermore, as a preferred embodiment of the propeller shaft of the present invention, at least a part in the axial direction has a laminated structure, and at least one layer of the thermosetting resin in the laminated portion is 30 wt. It is mentioned that it is a fiber reinforced plastic which consists of a resin composition containing the epoxy resin more than trifunctional and less than 70 weight part.

  In this case, the layer in which the thermosetting resin is a fiber-reinforced plastic made of a resin composition containing 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher epoxy resin in 100 parts by weight of the total epoxy resin is 45 It is preferable to include a spirally wound layer of ± 5 °.

  According to the present invention, it is possible to provide a propeller shaft that is excellent in heat resistance and has very little deterioration in mechanical properties even when used at a temperature exceeding 150 ° C.

  Furthermore, it is possible to suppress the deterioration of the mechanical characteristics even under a local high-temperature environment caused by the underfloor design of the automobile.

  The present invention is the above-mentioned problem, ie, a propeller shaft that is excellent in heat resistance and has very little deterioration in mechanical properties even when used at a temperature exceeding 150 ° C. When the ratio is in a specific range and relationship, that is, when the torsional strength of the propeller shaft in a 25 ° C environment is T1, and the static torsional strength in a 150 ° C environment is T2, T2 / T1 ≧ 0 In the case of .83, it has been found that the above-mentioned problems can be solved at once.

  In the present invention, the epoxy resin refers to a compound having one or more epoxy groups in the molecule, and the resin composition refers to an uncured composition containing the epoxy resin, for example, an epoxy resin and a curing agent, Furthermore, it refers to a composition containing other additives. Further, the total epoxy resin refers to all epoxy resins when one or more of the above epoxy resins are used.

  In the present invention, a trifunctional or higher functional epoxy resin refers to a compound having three or more epoxy groups in one molecule.

  The thermosetting resin is composed of a resin composition containing 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher functional epoxy resin in 100 parts by weight of the total epoxy resin. When the amount of trifunctional or higher epoxy resin is 30 parts by weight or less with respect to 100 parts by weight of the total epoxy resin, it may be difficult to maintain the physical properties at the high temperature expected by the present invention. The toughness of the resin itself may decrease, and the torsional strength of the propeller shaft may decrease.

  In particular, since propeller shafts for automobiles rotate at a high speed, it is necessary to design a high critical rotational speed in bending resonance and to maintain a torsional strength against a high torque transmitted from the engine. Therefore, in order to design a high critical rotational speed, it is preferable that the reinforcing fibers are oriented in the axial direction of the FRP main body cylinder and designed in the range of 0 to 20 °. On the other hand, it is effective to orient the torsional strength in the 45 ° direction of the reinforcing fiber, and it is preferable to include circumferential winding in order to prevent buckling deformation. As described above, the FRP body cylinder is composed of a combination of orientation angles of circumferential winding 80 to 90 °, axial winding 0 to 20 °, and roughly 45 ° winding in accordance with required specifications. Depending on the dimensional conditions such as the inner diameter and outer diameter of the FRP main body cylinder, the performance of the dangerous rotation speed and torsional strength of the FRP main body cylinder is designed.

  The ratio of the static torsional strength of the fiber reinforced plastic at normal temperature and high temperature, that is, T2 / T1 ≧ 0 when the strength at 25 ° C. environment (RT) is T1 and the strength at 150 ° C. is T2. By setting it to 83, it becomes possible to achieve the torsional strength required with a margin of 1.2 times, and material costs and manufacturing costs can be greatly reduced. As a result, the weight reduction of the FRP product can be achieved, and a propeller shaft that meets the original purpose can be provided.

  That is, for example, in the conventional epoxy resin configuration, the torsional strength is greatly reduced from room temperature to high temperature, and the ratio of the static torsional strength is about 0.5 to 0.7, so it is necessary to increase the initial strength. For this reason, it was necessary to provide a margin of about 1.4 to 2 times in advance, but such extra worry and technical addition became unnecessary.

  By the way, it is preferable to use a trifunctional or higher functional epoxy resin as a matrix resin for imparting heat resistance. As such a resin, N, N, N ′, N′-tetraglycidyl-4,4′-diamino is used. Diphenylmethane, N, N, O-triglycidyl-m-aminophenol, N, N, O-triglycidyl-p-aminophenol, alkyl substituted derivatives thereof, N, N, N ′, N′-tetraglycidyl-m- Xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, and 4,4′-diaminodiphenylsulfone added as a curing agent are preferred from the viewpoint of improving heat resistance. In addition, in this resin system, when a low-viscosity resin composition that has high viscosity and can be applied to filament winding molding is used, the range of resin selection is considerably narrow, but this is impregnated into reinforcing fibers in advance and processed into a sheet shape. Use of a prepreg can be preferably applied because the degree of freedom of resin blending is expanded.

  In addition, if a low-viscosity matrix resin is selected, the inner layer is composed of a conventional resin, and the outer layer is continuously molded by a filament winding method using a heat-resistant low-viscosity heat-resistant resin. Is also possible.

  As the resin at this time, in addition to the bisphenol A type epoxy resin, N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane, N, N, O-triglycidyl-m-aminophenol, N, N, O-triglycidyl-p-aminophenol, their alkyl-substituted derivatives, N, N, N ′, N′-tetraglycyl-m-xylenediamine, and 1,3-bis (N, N-diglycidyl Aminomethyl) cyclohexane can be used. The curing agent can be obtained by a combination of diethyltoluenediamine, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone and the like.

To increase the heat resistance and increase the ratio of T2 / T1, in addition to increasing the ratio of the trifunctional resin within the range of the present invention, by increasing the thickness ratio of the trifunctional or higher functional epoxy resin layer It becomes possible.
As the reinforcing fiber used in the present invention, a high-strength, high-modulus fiber such as carbon fiber, glass fiber, or polyaramid fiber, which is commonly used as a reinforcing fiber in FRP, can be used.

  The propeller shaft of the present invention has an FRP main body cylinder and joints attached to both ends of the main body cylinder. The FRP main body cylinder is a filament winding method, a sheet winding method, a tape winding method, or a combination thereof. It is preferable to form by.

  As is well known, the filament winding method is a method in which a reinforcing fiber impregnated with a thermosetting resin is wound around a mandrel, and after the thermosetting resin is cured, the mandrel is pulled out. In order to rotate at high speed, it is necessary to design a high critical speed in bending resonance, and in order to achieve the necessary axial elastic modulus, the reinforcing fiber winding structure is a spiral winding of ± 5 to 20 °. In order to satisfy the specification of the torsional strength together with the single configuration according to the above, it is preferable to configure with ± 30 to 60 ° spiral winding. In order to ensure the torsional buckling strength of the main body cylinder, it is also preferable to adopt a hybrid configuration in which a hoop layer of 75 to 90 ° is used in combination with the inner layer and the outer layer. In addition, for the purpose of improving the joint strength of the end portion to which the joint is attached, a layer having a winding configuration other than the above may be included, such as partially providing a thick hoop winding layer at the end portion. is there.

  The sheet winding method is also well known as a method of forming a cylindrical body. A prepreg sheet pre-impregnated with a thermosetting resin in one direction is wrapped around a mandrel and then tightened with film tape and thermoset. In this method, the mandrel is pulled out after the adhesive resin is cured. In particular, the propeller shaft for automobiles needs to be designed with a high critical speed in bending resonance because it rotates at high speed, and the required axial elastic modulus is therefore required. Therefore, the winding structure of the reinforcing fiber is preferably composed of a laminate in the direction of approximately 0 ° and a bias layer of approximately ± 45 ° in order to satisfy the torsional strength specification. In order to ensure the torsional buckling strength of the main body tube, it is also preferable to adopt a hybrid configuration in which a substantially 90 ° direction layer is used in combination with the inner layer and the outer layer. In addition, for the purpose of improving the bonding strength of the end portion to which the joint is mounted, a layer having a winding structure other than the above may be included, such as providing a partially thick 90 ° layer at the end portion. is there.

  The wall thickness of the main body cylinder is preferably about 1.5 to 4.7 mm because static torsional strength is required to be about 2000 to 5000 Nm, particularly in the case of an automobile propeller shaft. If the wall thickness is less than 1.5 mm, the torsional strength and the bending rigidity both decrease, and if it exceeds 4.7 mm, the torsional strength and the torsional rigidity become overspec, and the material becomes wasteful. Of course, the wall thickness also depends on the type of reinforcing fiber and the winding configuration and molding method described above.

  In the filament winding method, the spiral winding layer of ± 5 to 20 ° and ± 30 to 60 ° is set to 1.5 to 4.0 mm, and the spiral winding layer of ± 75 to 90 ° is set to 0.2 to 0.7 mm. Is preferred. Further, in the sheet winding method, a laminate of approximately 0 ° direction and a bias layer of approximately ± 45 ° in order to satisfy the specifications of the torsional strength are set to 1.5 to 4.0 mm, and approximately 90 ° direction layer. Is preferably 0.2 to 0.7 mm.

  The inner diameter of the FRP body cylinder is particularly preferably in the range of 50 to 90 mm in order to achieve the specifications of torsional strength and dangerous rotational speed.

  After finishing predetermined lamination by the FW method and the sheet winding method, the surface is wound with a surface layer material, after surplus resin is squeezed out, the epoxy resin is cured in a curing furnace to obtain a desired FRP cylindrical body. it can. Furthermore, after extracting the FRP molded product from the mandrel, a desired FRP cylindrical body can be obtained by cutting at a predetermined position and length.

  Depending on the under-floor configuration of the automobile, the propeller shaft may require heat resistance only locally due to the proximity of the exhaust pipe or the catalyst device. As described above, the thermosetting resin can be used as a whole in a resin composition containing 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher epoxy resin in 100 parts by weight of the total epoxy resin. In such a case, it is also preferable to partially use a resin composition in which the thermosetting resin contains 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher functional epoxy resin in 100 parts by weight of the total epoxy resin. If the heat resistance requirement is partial and sufficient, a part of the axial direction has a laminated structure, and at least one of the laminated parts is a fiber reinforced plastic using the resin composition, which is necessary. Heat resistance can be satisfied. At least a part of the axial direction has a laminated structure, and at least one layer of the thermosetting resin in the laminated part is 30 parts by weight or more and less than 70 parts by weight of trifunctional or higher epoxy resin in 100 parts by weight of the total epoxy resin. As a method for providing a fiber reinforced plastic layer made of a resin composition containing, a prepreg made of the resin composition can be obtained by a sheet winding method before, during or after formation of the layer by filament winding. In the winding work by sheet winding, the thermosetting resin partially uses a resin composition containing a trifunctional or higher functional epoxy resin of 30 parts by weight or more and less than 70 parts by weight in 100 parts by weight of the total epoxy resin, By performing partial application, the winding operation can be easily performed with high accuracy. In addition, since the necessary heat-resistant torsional strength can be obtained with the minimum amount of material only in the necessary parts, it is possible to maximize the lightening effect that is the original purpose of using the FRP cylindrical body. Become.

  From the viewpoint of securing torsional strength, a fiber reinforced plastic layer comprising a resin composition in which the thermosetting resin contains 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher functional epoxy resin in 100 parts by weight of the total epoxy resin. Preferably includes a spirally wound layer of at least approximately 45 ± 5 °. By adopting such a laminated structure, the propeller shaft can ensure the necessary bending rigidity and torsional strength.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embodiment of a propeller shaft to which the present invention is applied. End reinforcing layers 2d are disposed at both ends of the FRP main body cylinder 2, and the metal joint 3 is provided with serrations 3a, which are assembled and integrated by press-fitting. The propeller shaft is characterized in that T2 / T1 ≧ 0.83 where T1 is the static torsional strength in a 25 ° C. environment and T2 is the static torsional strength in a 150 ° C. environment. . The FRP cylindrical body is composed of reinforcing fibers and a thermosetting resin, and the thermosetting resin contains 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher functional epoxy resin in 100 parts by weight of the total epoxy resin. It is comprised by the resin composition. Further, FIG. 2 shows the configuration of the FRP main body cylinder. The laminated structure of the reinforcing fibers in the central part is composed of a combination of a circumferential winding of 80 to 90 ° and an axial winding of 0 to 20 °, with the innermost layer 2a and the outermost layer 2c having a circumferential winding of 80 to 90 °. The layer 2b is a main layer composed of a spiral wound layer of 5 to 20 ° and extending in the axial direction. Further, an end reinforcing layer 2d is provided at the end in order to ensure the torsional strength in the press-fitting.

  FIG. 3 shows another example of a preferred form of the FRP main body cylinder in the present invention. The FRP cylindrical body 2 is composed of reinforcing fibers and a thermosetting resin, and the thermosetting resin contains 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher functional epoxy resin in 100 parts by weight of the total epoxy resin. It is comprised by the resin composition to do. Further, the laminated structure of the reinforcing fibers in the central portion of the FRP main body cylinder is composed of a combination of an orientation angle of 80 to 90 ° in the circumferential direction, 0 to 20 ° in the axial direction and approximately 45 °, and the innermost layer 2a and the outermost layer. Reference numeral 2c denotes a circumferential winding of 90 [deg.], And the main layer 2b includes a 2b-1, 2b-3 composed of a 0 [deg.] Layer and a 45 [deg.] Layer 2b-2 and extends in the axial direction. In addition, an end reinforcing layer 2d configured by 90 ° is provided at the end in order to ensure the torsional strength in the press-fitting.

  FIG. 4 shows another example of the preferable form of the FRP main body cylinder in the present invention. The FRP cylinder 2 is composed of reinforcing fibers and thermosetting resins (A) and (B), and the thermosetting resin (B) is 30 parts by weight or more and 70 parts by weight in 100 parts by weight of the total epoxy resin. It is comprised by the resin composition containing the less than trifunctional or more than epoxy resin. Further, the laminated structure of the reinforcing fibers in the central portion of the FRP main body cylinder is composed of a combination of an orientation angle of 80 to 90 ° in the circumferential direction, 0 to 20 ° in the axial direction and approximately 45 °, and the innermost layer 2a and the outermost layer. 2c is composed of a circumferential winding of 80 to 90 °, the main layer 2b is composed of 2b-1 and 2b-3 consisting of a 5 to 20 ° layer, and a spiral winding layer 2b-2 of approximately 45 ° is formed in the middle part. The main layer extending in the axial direction is shown, and the approximately 45 ° spirally wound layer is made of the thermosetting resin (B). In this case, the thickness of the thermosetting resin (B) includes at least 20% in thickness ratio. In addition, an end reinforcing layer 2d composed of 80 to 90 ° is provided at the end in order to ensure torsional strength in the press-fit joining.

  FIG. 6 shows another example of a preferable form of the FRP main body cylinder in the present invention. The FRP cylindrical body 2 is composed of reinforcing fibers and thermosetting resins (A) and (B), and the thermosetting resin (B) is 30 parts by weight or more and less than 70 parts by weight in 100 parts by weight of the total epoxy resin. And a resin composition containing a trifunctional or higher functional epoxy resin. A laminated structure 2e that is partially and cylindrically arranged with respect to the axial direction of the main body cylinder made of the thermosetting resin (B) is configured. Further, the FRP laminated structure 2e is composed of a spirally wound layer having an orientation angle of at least approximately 45 °. As for the other part, as shown in FIG. 7, the lamination | stacking structure of the main layer which consists of the above-mentioned thermosetting resin (A) is the circumferential direction winding 80-90 degrees, the axial direction winding 0-20 degrees, and the orientation angle of about 45 degrees. The innermost layer 2a and the outermost layer 2c are wound in the circumferential direction of 80 to 90 °, the main layer 2b is composed of 5 to 20 ° layers 2b-1 and 2b-3, and the intermediate portion is further outlined. A main layer constituted by 2b-2 of a 45 ° spirally wound layer and extending in the axial direction is shown. As described above, it is also preferable to provide a circumferential reinforcing layer 2d at the end portion for bonding. The order of lamination can be changed by the molding method, and a partial layer made of a thermosetting resin (A) is formed in advance and partially and cylindrically formed of a thermosetting resin (B). It is also possible to arrange the laminated structure and mold with the thermosetting resin (A) outside thereof.

  FIG. 5 shows an outline of the torsion evaluation test of the propeller shaft. The torsion test FRP main body cylinder 4 in which the torsion test joints 4a and 4b are press-fitted at both ends is fixed to the flange portion of the torsion tester. At this time, one of the movable part flanges 5a has a rotational drive part by hydraulic pressure, and a torque load can be applied to the specimen. The other fixed portion flange 5b is fixed to the tester base, and the torque at the time of breakage can be detected from the load cell 5c connected to the flange portion. In addition, since the test temperature is important in the present invention, the torsion test was performed after adjusting and holding the temperature at a predetermined temperature using the thermostatic chamber 6 shown in FIG. The ambient temperature was detected from the thermometer 6a in the figure. The test speed and temperature setting during the torsion test are set by the control device shown in FIG.

Example 1
Embodiments will be described with reference to FIGS. 1 and 2. Three carbon fibers "Torayca (registered trademark)" T700SC-24K manufactured by Toray Industries, Inc. are arranged, and 50 parts of bisphenol A type epoxy resin (Epicoat (registered trademark) 827 manufactured by Japan Epoxy Resin Co., Ltd.) is added to this. 90 parts by weight of an acid anhydride-based curing agent (manufactured by Nippon Kayaku Co., Ltd.) with respect to 100 parts of an epoxy main agent composed of 50 parts of a trifunctional epoxy resin (“Epicoat (registered trademark)” 630 manufactured by Japan Epoxy Resin Co., Ltd.) While impregnating a mixed resin formed by adding “Kayahard (registered trademark)” MCD) and 1 part by weight of a curing accelerator (“Curesol (registered trademark)” manufactured by Shikoku Kasei Kogyo Co., Ltd.), by the filament winding method, After forming a spiral wound layer 2 a 0.2 mm of 85 ° on the inner layer with respect to the axial direction on a mandrel of φ70 mm, Then, after spirally winding a thickness of 1 mm at ± 12 °, after spirally winding a thickness of 0.5 mm at ± 45 ° and a thickness of 1 mm at ± 12 °, the outermost layer is a spirally wound layer 2c0 of 85 ° .2 mm was performed. The main layer is composed of a total of 2.9 mm. In addition, in a portion corresponding to a length of 110 mm at both ends of the main body cylinder, which is a fitting portion, a thickness constituted by ± 83 ° with respect to the axial direction is provided in order to improve the joint strength with the joint. A reinforcing layer 2d of 2.5 mm was formed. The reinforcing layer 2d is formed of a straight portion having a thickness of 2.5 mm and an axial length of 60 mm and a tapered portion having a length of 50 mm toward the axial center.

Thereafter, curing was performed in a curing furnace. The curing temperature was 100 ° C. × 2 hr + 200 ° C. × 4 hr, and FRP cylindrical body 2 was obtained.
Next, the metal joint 3 to be joined to both ends of the FRP cylindrical body 2 has a serration portion 3a. The serration used was a serration with a pitch of about 2 mm, a tooth height of 0.9 mm, a tip R of 0.04 mm, and a tooth tip angle of 90 degrees, and the outer diameter was processed to 74.45 mm. Therefore, it has a press-fitting allowance of 0.40 mm in diameter. The metal joint 3 was press-fitted and joined to the FRP cylindrical body 2 to form a propeller shaft 1 and then evaluated by a torsion tester.
FIG. 5 shows an overview of the torsion test. The torsion test FRP main body cylinder 4 in which the torsion test joints 4a and 4b are press-fitted at both ends is fixed to the flange portion of the torsion tester. At this time, one of the movable part flanges 5a has a rotational drive part by hydraulic pressure, and a torque load can be applied to the specimen. The other fixed portion flange 5b is fixed to the tester base, and torque can be detected from the load cell 5c connected to the flange portion. In addition, since the test temperature is important in the present invention, the torsion test was performed after adjusting and holding the temperature at a predetermined temperature using the thermostatic chamber 6 shown in FIG. The ambient temperature was detected from the thermometer 6a in the figure. The test speed and temperature setting during the torsion test are set by the control device shown in FIG.

Table 1 shows the relationship between the ambient temperature T (° C.) and the torsional strength S (kN · m) in this torsion test. T1 = 5.2 kNm in a 25 ° C. environment and 150 ° C. in a 150 ° C. environment. As a result of T2 = 4.42 kNm and T2 / T1 = 0.85, a propeller shaft excellent in heat resistance with little decrease in torsional strength even under a high temperature environment could be obtained.
(Example 2)
An embodiment will be described with reference to FIG. Carbon fiber "Torayca (registered trademark)" T700S-12K made by Toray Industries, Inc. 30 parts of bisphenol A type epoxy resin ("Epicoat (registered trademark)" 825 manufactured by Japan Epoxy Resin Co., Ltd.), Bisphenol F type 100 parts of epoxy (Dainippon Ink Chemical Co., Ltd. “Epicron (registered trademark)” 830) A total of 40 parts of trifunctional epoxy resin (Sumitomo Chemical Industries “Sumiepoxy (registered trademark)” ELM434) 60 parts of epoxy main agent 100 A prepreg having a thickness of 0.135 mm impregnated with 16 parts of diaminodiphenylsulfone (Sumitomo Chemical “SumiCure®” S) and 16 parts of polyethersulfone (“SUMICA EXCEL®” PES5003P) Forming by sheet winding molding using a sheet is performed as follows. . After a 90 ° winding layer 2a 0.27 mm is formed on the inner layer of a φ70 mm mandrel with respect to the axial direction, a 0 ° thickness 0.81 mm 2b-1 is wound as the main layer 2b, and then a bias configuration of + 45 ° -45 After winding 2b-2 having a thickness of 0.54 mm at 0 °, and further 2b-3 having a thickness of 0 ° and 0.81 mm, the outer layer was formed into a 90 ° wound layer 2c of 0.27 mm, and then the outermost layer. The film tape was wrapped. The main layer 2b is composed of a total of 2.7 mm. In order to improve the joint strength with the joint, a reinforcing layer made of 90 ° with a thickness of 2.5 mm is provided on the portion corresponding to the length of 110 mm at both ends of the main body cylinder, which is the fitting mounting portion. Formed. The reinforcing layer 2d is formed of a straight portion having a thickness of 2.56 mm and an axial length of 60 mm and a tapered portion having a length of 50 mm toward the axial center.

  Thereafter, curing was performed in a curing furnace. The curing temperature was 100 ° C. × 2 hr + 200 ° C. × 4 hr, and FRP cylinder 2 was obtained.

  Next, the metal joint 3 to be joined to both ends of the FRP cylindrical body 2 has serrations. The serration used was a serration with a pitch of about 2 mm, a tooth height of 0.9 mm, a tip R of 0.04 mm, and a tooth tip angle of 90 degrees, and the outer diameter was processed to 74.45 mm. Therefore, it has a press-fitting allowance of 0.40 mm in diameter. The metal joint 3 was press-fitted and formed into a propeller shaft, and then evaluated by a torsion tester.

Table 1 shows the relationship between the ambient temperature T (° C.) and the torsional strength S (kNm) in this torsion test. T1 = 4.2 kNm in a 25 ° C. environment and T 2 = in a 150 ° C. environment. The result was 3.8 kNm, T2 / T1 = 0.9, and a propeller shaft excellent in heat resistance with little decrease in torsional strength even under a high temperature environment could be obtained.
(Example 3)
The embodiment will be described with reference to FIG. Three carbon fibers "Torayca (registered trademark)" T700SC-24K manufactured by Toray Industries, Inc. are arranged, and 100 parts of bisphenol A type epoxy resin ("Epicoat (registered trademark)" 827 manufactured by Japan Epoxy Resin Co., Ltd.) 90 parts by weight of an acid anhydride curing agent (“Kayahard (registered trademark)” MCD manufactured by Nippon Kayaku Co., Ltd.) and 1 part by weight of a curing accelerator (“Curesol (registered trademark)” manufactured by Shikoku Kasei Kogyo Co., Ltd.) After the impregnated mixed resin (A) is added, a spiral winding layer of 0.2 mm is formed on the inner layer with respect to the axial direction on a φ70 mm mandrel by a filament winding method, and then ± 12 as the main layer After being spirally wound at a thickness of 1 mm at ° C, this was added to a bisphenol A type epoxy resin ("Epicoat (registered trader) manufactured by Japan Epoxy Resin Co., Ltd. ) 90 parts by weight of an acid anhydride system based on 100 parts of an epoxy main agent composed of 30 parts of a trifunctional epoxy resin (“Epicoat (registered trademark)” 630 manufactured by Japan Epoxy Resin Co., Ltd.) with respect to 70 parts of “827)” A mixed resin obtained by adding a curing agent (“Kayahard (registered trademark)” MCD manufactured by Nippon Kayaku Co., Ltd.) and 1 part by weight of a curing accelerator (“Cureazole (registered trademark)” manufactured by Shikoku Kasei Kogyo Co., Ltd.) After impregnating B), laminating 0.6 mm thick at ± 45 °, and further spirally winding 0.9 mm thick mixed resin (A) ± 12 °, and then outermost layer 85 ° A spiral wound layer of 0.2 mm was carried out. The main layer consists of a total of 2.9 mm. In addition, in the part corresponding to the length of 110 mm at both end portions of the main body cylinder, which is the fitting mounting part, the thickness is increased from 2.5 mm before the application of the mixed resin in order to improve the joint strength with the joint. A reinforcing layer was formed. The reinforcing layer 2d is formed of a straight portion having a thickness of 2.5 mm and an axial length of 60 mm and a tapered portion having a length of 50 mm toward the axial center.

  Thereafter, curing was performed in a curing furnace. The curing temperature was 100 ° C. × 2 hr + 200 ° C. × 4 hr, and FRP cylinder 2 was obtained.

  Next, the metal joint 3 to be joined to both end portions of the main body cylinder has a serration portion. The serration part 3a used a serration having a pitch of about 2 mm, a tooth height of 0.9 mm, a tip R of 0.04 mm, and a tooth tip angle of 90 degrees, and the outer diameter was processed to 74.45 mm. Therefore, it has a press-fitting allowance of 0.40 mm in diameter. The metal joint 3 was press-fitted and formed into a propeller shaft, and then evaluated by a torsion tester.

Table 1 shows the relationship between the ambient temperature T (° C.) and the torsional strength S (Nm) in this torsion test. T1 = 5.5 kNm in a 25 ° C. environment and T 2 = in a 150 ° C. environment. As a result of 4.6 kNm, T2 / T1 = 0.84, and it was possible to obtain a propeller shaft excellent in heat resistance with little decrease in torsional strength even in a high temperature environment.
Example 4
The embodiment will be described with reference to FIG. Carbon fiber "Torayca (registered trademark)" T700S-12K made by Toray Industries, Inc. 30 parts of bisphenol A type epoxy resin ("Epicoat (registered trademark)" 825 manufactured by Japan Epoxy Resin Co., Ltd.), Bisphenol F type 100 parts of epoxy (Dainippon Ink Chemical Co., Ltd. “Epicron (registered trademark)” 830) A total of 40 parts of trifunctional epoxy resin (Sumitomo Chemical Industries “Sumiepoxy (registered trademark)” ELM434) 60 parts of epoxy main agent 100 A prepreg having a thickness of 0.135 mm impregnated with 16 parts of diaminodiphenylsulfone (Sumitomo Chemical “SumiCure®” S) and 16 parts of polyethersulfone (“SUMICA EXCEL®” PES5003P) Forming by sheet winding molding using a sheet is performed as follows. . A partially laminated structure having a thickness of 0.54 mm is wound on a mandrel with a diameter of 70 mm with a spiral winding structure of + 45 ° and −45 ° with respect to its axial direction over a length of 300 mm. Thereafter, 90 parts by weight of an acid anhydride curing agent (“Kayahard” manufactured by Nippon Kayaku Co., Ltd.) is added to 100 parts of bisphenol A type epoxy resin (“Epicoat (registered trademark)” 827 manufactured by Japan Epoxy Resin Co., Ltd.). While impregnating the mixed resin (A) obtained by adding (registered trademark) “MCD” and 1 part by weight of a curing accelerator (“Curesol (registered trademark)” manufactured by Shikoku Kasei Kogyo Co., Ltd.), by the filament winding method, After forming a spiral winding layer 0.2 mm of 85 ° on the inner layer of the mandrel with respect to its axial direction, the main layer was spirally wound with a thickness of 1 mm at ± 12 ° and then a thickness of 0.6 mm at ± 45 °. After laminating, spiral winding with a thickness of 0.9 mm at ± 12 ° was performed, and then the outermost layer was formed with a spiral winding layer of 0.2 mm at 85 °. The main layer consists of a total of 2.9 mm. In addition, in order to improve the joint strength with the joint, the thickness from 2.5 mm before the application of the mixed resin is applied to the part corresponding to the length of 110 mm at both ends of the main body cylinder, which is the fitting part. A reinforcing layer was formed. The reinforcing layer 2d is formed of a straight portion having a thickness of 2.5 mm and an axial length of 60 mm and a tapered portion having a length of 50 mm toward the axial center.

  Thereafter, curing was performed in a curing furnace. The curing temperature was 100 ° C. × 2 hr + 200 ° C. × 4 hr, and FRP cylinder 2 was obtained.

  Next, the metal joint 3 to be joined to both ends of the FRP cylindrical body 2 has serrations. The serration used was a serration with a pitch of about 2 mm, a tooth height of 0.9 mm, a tip R of 0.04 mm, and a tooth tip angle of 90 degrees, and the outer diameter was processed to 74.45 mm. Therefore, it has a press-fitting allowance of 0.4 mm in diameter. The metal joint 3 was press-fitted and formed into a propeller shaft, and then evaluated by a torsion tester. In order to achieve a local high temperature condition, a ribbon heater is wrapped around the partial laminate while maintaining the ambient temperature at 120 ° C, and a torsion test is performed while the temperature of the FRP body cylinder is partially maintained at 150 ° C by a thermometer. Carried out.

In this torsion test, the fracture torque was 4.0 kNm under a partial 150 ° C. environment, and a propeller shaft excellent in heat resistance with little decrease in torsional strength even under a local high temperature environment could be obtained. Here, the torsional strength of the FRP cylindrical body of this example is T1 = 5.5 kNm under the environment of 25 ° C., and T2 / T1 = 0.85 under the result of T2 = 4.67 kNm under the environment of 150 ° C. Yes, it was possible to obtain a propeller shaft excellent in heat resistance with little decrease in torsional strength even in a high temperature environment.
(Comparative example)
In contrast to the examples, unlike the resin composition of the present invention, the FRP body cylinder according to the following comparative example was molded and the torsional strength test was conducted as a case not containing a polyfunctional resin. Three carbon fibers "Torayca (registered trademark)" T700SC-24K manufactured by Toray Industries, Inc. are arranged, and 100 parts of bisphenol A type epoxy resin ("Epicoat (registered trademark)" 827 manufactured by Japan Epoxy Resin Co., Ltd.) 90 parts of an acid anhydride curing agent (“Kayahard (registered trademark)” MCD manufactured by Nippon Kayaku Co., Ltd.) and 1 part of a curing accelerator (“Curesol (registered trademark)” manufactured by Shikoku Kasei Kogyo Co., Ltd.) While impregnating the mixed resin to be added, a filament winding method is used to form a spiral wound layer 0.2 mm of 85 ° on the inner layer with respect to the axial direction on a φ70 mm mandrel, and then a thickness of ± 12 ° as a main layer After spirally winding 1 mm, after winding spirally 0.5 mm at ± 45 ° and 1 mm thick at ± 12 °, the outermost layer is 1 layer of 85 ° . The main layer is composed of a total of 2.9 mm.

  Thereafter, curing was performed in a curing furnace. The curing temperature was 100 ° C. × 2 hr + 200 ° C. × 4 hr, and an FRP cylinder was obtained. In addition, in the part corresponding to the length of 110 mm at both end portions of the main body cylinder, which is the fitting mounting part, the thickness is increased from 2.5 mm before the application of the mixed resin in order to improve the joint strength with the joint. A reinforcing layer was formed. The reinforcing layer 2d is formed of a straight portion having a thickness of 2.5 mm and an axial length of 60 mm and a tapered portion having a length of 50 mm toward the axial center.

  Next, the joint member joined to both ends of the main body cylinder has serration portions. The serration used was a serration with a pitch of about 2 mm, a tooth height of 0.9 mm, a tip R of 0.04 mm, and a tooth tip angle of 90 degrees, and the outer diameter was processed to 74.45 mm. Therefore, it has a press-fitting allowance of 0.40 mm in diameter. The metal joint was press-fitted and formed into a propeller shaft, and then evaluated by a torsion tester.

  Table 1 shows the relationship between the ambient temperature T (° C.) and the torsional strength S (kNm) in this torsion test. T1 = 5.2 kNm in a 25 ° C. environment and T 2 = in a 150 ° C. environment. The result is 2.96 kNm. When this result is expressed by the parameter of the present invention, T1 / T2 = 0.57, and the result of the present invention containing 30 parts by weight or more and less than 70 parts by weight of the polyfunctional resin is 0.85. It is significantly reduced and the torsional strength under high temperature environment cannot be maintained.

The propeller shaft according to the present invention can be applied to any propeller shaft provided with an FRP cylindrical body, and is particularly suitable for an FRP propeller shaft for automobiles that require heat resistance as environmental characteristics.

It is a schematic sectional drawing which shows the principal part of an example of the propeller shaft of this invention. It is a schematic sectional drawing which shows an example of a structure of the main body cylinder made from FRP of the propeller shaft of this invention. It is a schematic sectional drawing which shows another example of a structure of the main body cylinder made from FRP of the propeller shaft of this invention. It is a schematic sectional drawing which shows another example of a structure of the main body cylinder made from FRP of the propeller shaft of this invention. It is a perspective view which shows the mode of a twist test. It is a schematic sectional drawing which shows another example of a structure of the main body cylinder made from FRP of the propeller shaft of this invention.

Explanation of symbols

1 Propeller shaft 2 FRP cylinder 2a Inner layer
2b Main layer 2c Outer layer
2d Reinforcing layer 2e Axial partial layer 3 Metal joint 3a Serration part 4 Torsion test FRP body cylinder 4a, b Torsion test joint 5 Torsion tester 5a Movable part flange 5b Fixed part flange 5c Load cell 5d Rotating part 6 Constant temperature bath 6a Temperature detector 7 Hydraulic pump 8 Controller

Claims (4)

In a propeller shaft having a main body cylinder and joints attached to both ends of the main body cylinder, the main body cylinder is made of a fiber reinforced plastic obtained by reinforcing a thermosetting resin with a reinforcing fiber, and the fiber reinforced A propeller shaft, wherein T2 / T1 ≧ 0.83, wherein T1 is a static torsional strength of a plastic in an environment of 25 ° C. and T2 is a static torsional strength in an environment of 150 ° C. The said thermosetting resin is comprised by the resin composition containing 30 weight part or more and less than 70 weight part trifunctional or more than 30 weight part epoxy resin in 100 weight part of all the epoxy resins. Propeller shaft. At least a part in the axial direction has a laminated structure, and at least one layer of the laminated part is a trifunctional or higher functional epoxy having 30 parts by weight or more and less than 70 parts by weight in 100 parts by weight of the total epoxy resin. The propeller shaft according to claim 1, wherein the propeller shaft is a fiber-reinforced plastic made of a resin composition containing a resin. A layer in which the thermosetting resin is a fiber-reinforced plastic made of a resin composition containing 30 parts by weight or more and less than 70 parts by weight of a trifunctional or higher functional epoxy resin in 100 parts by weight of the total epoxy resin is at least 45 ± 5 The propeller shaft according to claim 3, which includes a spiral wound layer of 5 °.

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