Torsional damper and manufacturing method thereof

Abstract

To provide a method for manufacturing a torsional damper that can acquire a torsional damper that has high slip torque.SOLUTION: A method for manufacturing a torsional damper includes: a preheating process of preheating an unprocessed vibration ring and an unprocessed hub and providing a post-preheated vibration ring and a post-preheated hub having temperature of 50-130°C; an application step of applying torque improvement liquid to the post-preheated vibration ring and the post-preheated hub, and then drying them to provide a post-dried vibration ring and a post-dried hub; and a fitting step of fitting a rubber ring applied with fitting liquid to a part between the post-dried vibration ring and the post-dried hub.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a torsional damper and a method for manufacturing the same. [Background technology]

[0002] The torsional damper (hereafter referred to as TVD) is a product that has a rubber ring fitted between the hub and the vibration ring. This product is attached to the tip of the crankshaft and functions as a dynamic damper to reduce the torsional vibration of the crankshaft and to transmit power to auxiliary equipment (alternator, air conditioner, water pump) via a belt. As a result, torque is generated in the rubber ring between the hub and the vibration ring, but in order to maintain functionality, the rubber ring must not slip even when a certain amount of torque is generated. Therefore, a silane coupling-based torque-improving liquid is applied between the hub and rubber ring and between the vibration ring and rubber ring to improve the torque.

[0003] An example of a related art method in this regard is described in Patent Document 1. Patent Document 1 describes a method for manufacturing a torsional damper, which is characterized in that an adhesive in which an organic phosphorus compound is added to a mercapto group-containing silane coupling agent is applied to the outer peripheral surface of the rim portion and the inner peripheral surface of the annular mass, and then dried, and then an annular rubber is pressed into between the outer peripheral surface of the rim portion and the inner peripheral surface of the annular mass from the axial side (see claim 6).Then, according to this manufacturing method, the annular rubber is press-fitted between the opposing peripheral surfaces of a metal hub and a metal annular mass arranged on the outer peripheral side of the hub, and it is described that a torsional damper that does not necessarily require heat treatment after fitting can be provided that has a sliding torque equal to or greater than that of a conventional torsion damper provided with an adhesive layer consisting only of a mercapto group-containing silane coupling agent. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-16655 A Summary of the Invention [Problem to be solved by the invention]

[0005] It is preferable that the torsional damper have a higher slip torque. An object of the present invention is to provide a method for manufacturing a torsional damper that can obtain a torsional damper with high slip torque, and a torsional damper obtained by the manufacturing method. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to solve the above problems and have completed the present invention. The present invention relates to the following (1) to (3). (1) a preheating step in which an untreated vibration ring and an untreated hub are preheated to obtain a preheated vibration ring and a preheated hub at 50 to 130°C; a coating step of coating the preheated vibration ring and the preheated hub with a torque improving liquid and then drying the liquid to obtain a dried vibration ring and a dried hub; a fitting step of fitting a rubber ring, to which a fitting liquid has been applied, between the dried vibration ring and the dried hub; A method for manufacturing a torsional damper comprising: (2) A method for manufacturing a torsional damper as described above in (1), wherein in the preheating step, the untreated vibration ring and the untreated hub are degreased and then preheated. (3) A torsional damper manufactured by the method for manufacturing a torsional damper described in (1) or (2) above. Effect of the Invention

[0007] According to the present invention, it is possible to provide a manufacturing method for a torsional damper that can provide a torsional damper with high slip torque, and a torsional damper obtained by the manufacturing method. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic perspective view illustrating an embodiment of a torsional damper obtained by the manufacturing method of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional perspective view of the torsional damper shown in FIG. [Diagram 3] 1 is a schematic cross-sectional perspective view illustrating an embodiment of a post-drying vibration ring, a post-drying hub, and a rubber ring used in the manufacturing method of the present invention. FIG. [Figure 4] 1 is a graph showing the results of Experiment 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The manufacturing method of the present invention will be described with reference to the drawings. The manufacturing method of the present invention is a method for manufacturing a torsional damper that includes a preheating step in which an untreated vibrating ring and an untreated hub are preheated to obtain a preheated vibrating ring and a preheated hub at 50 to 130°C, a coating step in which a torque improving liquid is applied to the preheated vibrating ring and the preheated hub, followed by drying to obtain a dried vibrating ring and a dried hub, and a fitting step in which a rubber ring coated with a fitting liquid is fitted between the dried vibrating ring and the dried hub.

[0010] First, a torsional damper obtained by the manufacturing method of the present invention will be described with reference to FIGS. FIG. 1 is a schematic perspective view illustrating an embodiment of a torsional damper obtained by the manufacturing method of the present invention, and FIG. 2 is a schematic sectional perspective view of the torsional damper shown in FIG.

[0011] The torsional damper 1 of the embodiment illustrated in Figures 1 and 2 can be attached to the tip of the crankshaft of an engine of a vehicle or the like. The torsional damper 1 has the function of absorbing the torsional resonance of the crankshaft and suppressing the vibration and noise of the engine. In addition, it also serves as a drive pulley that transmits the power of the rotation of the crankshaft to an auxiliary device via a belt. The torsional damper 1 has a hub 3, a vibration ring 5, and a rubber ring 7.

[0012] The hub 3 is composed of a boss portion 31, a stay portion 33 and a rim portion 35. The boss portion 31 is provided at the radial center of the hub 3. The boss portion 31 is fastened to the tip of a crankshaft, and the hub 3 is driven to rotate about the central axis X. The stay portion 33 extends radially from the boss portion 31 . The rim portion 35 is provided on the outer periphery of the stay portion 33. The rim portion 35 is cylindrical, and the vibration ring 5 is connected to the outer periphery of the rim portion 35 via the rubber ring 7. Each of the boss portion 31, the stay portion 33 and the rim portion 35 can be formed using a metal material such as cast iron as a raw material.

[0013] The vibration ring 5 is disposed radially outside the hub 3, and has a pulley groove 51 on its outer circumferential surface, through which a belt is wound. The pulley groove 51 functions as a pulley for transmitting power. The vibration ring 5 can be formed using a metal material such as cast iron as a raw material.

[0014] The rubber ring 7 is inserted into the gap between the outer peripheral surface of the hub 3 and the inner peripheral surface of the vibration ring 5. The rubber ring 7 serves to reduce torsional vibration of the crankshaft generated while the vehicle is running, thereby preventing damage, and to reduce noise and vibration caused by the engine.

[0015] The rubber ring 7 can be obtained by vulcanizing a rubber composition containing ethylene-propylene-diene terpolymer (EPDM) as a main component and preferably also carbon black and process oil into a cylindrical shape by a conventionally known method. The rubber composition may contain zinc oxide, stearic acid, antioxidants, peroxides, crosslinking agents, etc. In addition, a rubber composition can also be obtained using natural rubber, a blended rubber of natural rubber and styrene-butadiene copolymer rubber, butadiene rubber, a blended rubber of natural rubber and butadiene rubber, styrene-butadiene copolymer rubber, chloroprene rubber, acrylonitrile-butadiene copolymer rubber, hydrogenated acrylonitrile-butadiene copolymer rubber, ethylene-acrylate copolymer rubber, fluororubber, acrylic rubber, or the like as a rubber material.

[0016] According to the manufacturing method of the present invention, for example, the torsional damper 1 shown in FIG. 1 and FIG. 2 can be obtained. However, the torsional damper obtainable by the manufacturing method of the present invention does not have to be in the form shown in Figures 1 and 2, so long as it is a rubber fitting type torsional damper manufactured by press-fitting a pre-vulcanized rubber ring between the outer peripheral surface of the hub and the inner peripheral surface of the vibration ring. According to the manufacturing method of the present invention, it is possible to obtain a torsional damper having, for example, a conventionally known shape and material.

[0017] <Preheating process> The preheating step in the manufacturing method of the present invention will be described. In the preheating step, the untreated vibration ring and the untreated hub are preheated by heating them to a temperature of 50 to 130°C. The untreated vibrating ring and the untreated hub refer to those having the same shape and made of the same material as the vibrating ring 5 and the hub 3 as exemplified in Figs. 1 and 2, and in a state prior to preheating.

[0018] The method for preheating the untreated vibrating ring and the untreated hub is not particularly limited. For example, the untreated vibrating ring and the untreated hub can be preheated by heating them to a temperature of 50 to 130°C by a conventionally known method. For example, they can be heated by placing them in a heating furnace whose inside is adjusted to 50 to 130°C. The temperature inside the heating furnace is preferably 70 to 130°C.

[0019] Here, the temperature of the untreated vibrating ring and / or the untreated hub refers to the surface temperature of the untreated vibrating ring and / or the untreated hub measured by a non-contact infrared thermometer.

[0020] The inventors have found that if the untreated vibration ring and the untreated hub are adjusted to the above temperature and the torque-improving liquid is applied before the temperature drops too much, that is, while the temperature is between 50 and 130°C, the applied torque-improving liquid reacts sufficiently with the untreated vibration ring and the untreated hub to firmly bond them together, and in addition, the torque-improving liquid also reacts sufficiently with the rubber ring fitted in the fitting step described below, so that the sliding torque of the torsional damper obtained by the manufacturing method of the present invention is further improved. The inventors have also confirmed that if the temperature is too high or too low, the effect is weakened.

[0021] Here, it is preferred to degrease the untreated vibrating ring and / or the untreated hub prior to preheating. The method for degreasing is not particularly limited, and for example, degreasing can be performed by a conventionally known method, such as an alkaline degreasing method using an alkaline agent.

[0022] By such a preheating step, a preheated vibration ring and a preheated hub having a temperature of 50 to 130°C can be obtained.

[0023] <Coating process> The coating step in the manufacturing method of the present invention will be described. In the application step, the torque improving liquid is applied to the preheated vibration ring and the preheated hub. The preheated ring and the preheated hub are the same in shape and material as the vibration ring 5 and the hub 3 as shown in Figs. 1 and 2, and are in a preheated state by the preheating process described above.

[0024] As the torque improving liquid, a solution in which a silane coupling agent is dissolved in a hydrocarbon solution (solvent) such as toluene or xylene can be mainly used. As the silane coupling agent, a urethane-based silane coupling agent, an epoxy-based silane coupling agent, or a vinyl-based silane coupling agent can be used, but it is preferable to use an amino group-containing silane coupling agent or a mercapto group-containing silane coupling agent, since they have a high torque improving effect. Examples of amino group-containing silane coupling agents include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-aminoethyl)aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropylmethyldiethoxysilane, γ-ureidopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, and N-vinylbenzyl-γ-aminopropyltriethoxysilane. Examples of the mercapto group-containing silane coupling agent include γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, and γ-mercaptopropylmethyldiethoxysilane. A mixture of two or more types of silane coupling agents can also be used.

[0025] The torque improving liquid mainly contains a silane coupling agent (preferably an amino group-containing silane coupling agent or a mercapto group-containing silane coupling agent), and preferably further contains a titanium acetylacetonate compound or an organophosphorus compound. Examples of the organic phosphorus compound include an organic phosphine compound, a quaternary phosphonium salt, and an organic phosphoric acid compound. The torque improving liquid preferably contains 5 to 100 parts by mass of the titanium acetylacetonate compound per 100 parts by mass of the amino group-containing silane coupling agent. The torque improving liquid preferably contains 1 to 100 parts by mass of the organophosphorus compound per 100 parts by mass of the mercapto group-containing silane coupling agent.

[0026] In the application step in the manufacturing method of the present invention, the torque improving liquid is applied to the preheated vibration ring and the preheated hub as described above. The method of application is not particularly limited, and may be a conventionally known method, such as spraying, dipping, or spraying.

[0027] The torque improving liquid is preferably applied sufficiently to the portions of the preheated vibration ring and the preheated hub that come into contact with the rubber ring, i.e., the inner peripheral surface of the preheated vibration ring and the outer peripheral surface of the rim part of the preheated hub. For example, it is preferable to apply the torque improving liquid so that the layer is 5 to 50 μm thick.

[0028] As described above, the torque improving liquid is applied to the preheated vibration ring and the preheated hub, and then dried.

[0029] There is no particular limitation on the method for drying the preheated vibration ring and the preheated hub to which the torque improving liquid has been applied, but they can be dried, for example, by heating using a conventionally known method. For example, the preheated vibration ring and the preheated hub coated with the torque improving liquid can be heated and dried by placing them in a heating furnace whose interior is adjusted to 40 to 130°C. In addition, for example, the torque-improving liquid can be dried by storing the pre-heated vibrating ring and the pre-heated hub to which the torque-improving liquid has been applied in a room at a specific temperature (for example, room temperature) for a certain period of time (for example, one day or more).

[0030] By such a coating process, a dried vibration ring and a dried hub can be obtained.

[0031] <Mating process> The fitting step in the manufacturing method of the present invention will be described. In the fitting step, a rubber ring coated with the fitting liquid is fitted between the dried vibration ring and the dried hub obtained in the coating step.

[0032] The fitting process will be described with reference to FIG. FIG. 3 is a schematic cross-sectional perspective view for explaining a method of fitting a rubber ring between the post-drying vibration ring and the post-drying hub. FIG. 3 shows a state in which the post-drying hub 30 and the post-drying vibration ring 50 are placed on a support (not shown) so that the boss portion 310 of the post-drying hub 30 is oriented vertically. In this state, the rubber ring 70 can be press-fitted into the gap 80 between the outer circumferential surface of the rim portion 350 in the post-dry hub 30 and the inner circumferential surface of the post-dry vibrating ring 50 using a press-fitting tool such as a press machine. Here, it is preferable that the width of the gap 80 is narrower than the thickness of the rubber ring 70. Specifically, it is preferable that the ratio of the width of the gap 80 to the thickness of the rubber ring 70 is about 0.6 to 0.9.

[0033] Here, it is preferable to apply a fitting liquid to the rubber ring 70 before fitting. The type of fitting liquid and the method of applying the fitting liquid are not particularly limited, and for example, a conventionally known fitting liquid can be used. The method of applying the fitting liquid is also not particularly limited, and for example, a conventionally known fitting liquid can be used.

[0034] According to the manufacturing method of the present invention, it is not necessary to apply heat after fitting, and it is possible to obtain a torsional damper with a sufficiently high sliding torque without applying heat.

[0035] After fitting the rubber ring between the post-drying vibration ring and the post-drying hub by the fitting step as described above, it is preferable to carry out alkaline cleaning. The method of alkaline cleaning is not particularly limited, and a conventionally known method, for example, a method of immersing in an alkaline solution, can be applied. EXAMPLES

[0036] An embodiment of the present invention will be described below. The scope of the present invention is not limited to the embodiment described below.

[0037] <Experiment 1> Four sets of untreated vibration rings and untreated hubs made of cast iron were prepared, and each was degreased by an alkaline degreasing method using an alkaline agent. Of these three sets, one each was placed in a heating furnace and preheated to 70°C, 100°C, and 130°C, respectively, to obtain a preheated vibration ring and a preheated hub. The remaining set was not preheated. Immediately after that (before the temperature had dropped), the torque improving liquid was applied to the three sets of preheated vibration rings and preheated hubs. In addition, the torque improving liquid was similarly applied to one set of untreated vibration rings and untreated hubs that had not been preheated. Here, as the torque improving liquid, a solution obtained by diluting 100 parts by mass of γ-mercaptopropyltrimethoxysilane and 20 parts by mass of tris(dichloropropyl)phosphate with 2000 parts by mass of toluene was used.

[0038] Next, the vibration ring and the hub coated with the torque improving liquid were dried by being held in a heating furnace with the internal temperature adjusted to 85° C. for 13 minutes to obtain a dried vibration ring and a dried hub.

[0039] Next, a rubber ring was prepared and coated with a fitting liquid (phthalate ester plasticizer), and then the rubber ring was pressed into the gap between the outer peripheral surface of the rim part of the dried hub and the inner peripheral surface of the dried vibration ring using a pressing tool such as a press machine as shown in Figure 3. After that, the ring was immersed in an alkaline cleaning solution to wash away the fitting liquid.

[0040] For the rubber ring, a rubber composition containing EPDM as a main component, which was obtained by crosslinking the following compounding composition at 180° C. for 6 minutes, was used. EPDM (Sumitomo Chemical): 100 parts by mass HAF carbon black: 50 parts by weight Zinc white: 5 parts by mass Stearic acid: 0.5 parts by weight Dicumyl peroxide: 3 parts by weight

[0041] In this manner, the torsional damper shown in Figs. 1 and 2 was obtained.

[0042] Next, the slip torque was measured for the four types of torsional dampers obtained. In this measurement, after fixing the hub and vibrating ring, a circumferential load was applied in increments of 20 N m and this state was maintained for one minute. If the relative torsional displacement between the hub and vibrating ring was less than 2 degrees within this holding time, the load was increased by a further 20 N m and maintained for one minute. The torque at which the relative torsional displacement between the hub and vibrating ring was 2 degrees or more within the holding time was recorded as the slip torque value. The results are shown in Figure 4. In Figure 4, a torsional damper obtained from a pair of untreated vibration rings and an untreated hub that were not preheated (hereinafter also referred to as the "comparison subject") was set as the standard (set at 1.0), and the slip torque values ​​were shown as relative values ​​to this.

[0043] As shown in FIG. 4, the slip torque of the torsional damper when preheated at 70° C., 100° C., and 130° C. exhibited better values ​​than the slip torque of the comparative torsional damper.

[0044] <Experiment 2> In Experiment 1, the vibrating ring and hub coated with the torque-enhancing liquid were dried by holding them in a heating furnace adjusted to a specific internal temperature to obtain a dried vibrating ring and a dried hub, whereas in Experiment 2, the vibrating ring and hub coated with the torque-enhancing liquid were dried by holding them in a room adjusted to 23°C for 24 hours to obtain a dried vibrating ring and a dried hub. Otherwise, the same procedures as in Experiment 1 were carried out, and the slip torque was measured in the same manner.

[0045] As a result, similarly to the case of Experiment 1, the slip torque of the torsional damper when preheated at 70°C, 100°C, and 130°C showed better values ​​than the slip torque of the comparison torsional damper. [Explanation of symbols]

[0046] 1 Torsional Damper 3. Hub 31 Boss section 33 Stay part 35 Rim section 5 Vibrating Ring 51 Pulley groove 7 Rubber ring 30 Hub after drying 310 Boss 350 Rim 50 Vibration ring after drying 80 Gap

Claims

1. a preheating step of preheating the untreated vibrating ring and the untreated hub to obtain a preheated vibrating ring and a preheated hub at 50 to 130°C; a coating step of coating the preheated vibration ring and the preheated hub with a torque improving liquid and then drying the liquid to obtain a dried vibration ring and a dried hub; a fitting step of fitting a rubber ring, to which a fitting liquid has been applied, between the dried vibration ring and the dried hub; A method for manufacturing a torsional damper comprising:

2. The method for manufacturing a torsional damper according to claim 1 , wherein in the preheating step, the untreated vibration ring and the untreated hub are preheated after being degreased.

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