JPH1078112A - Power transmitting member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a member which is excellent in wear resistance itself, but gently offensive to a mating member, and has a thermally stable proper frictional coefficient by blending an aromatic polyamide fiber, nonlinear inorganic filler, and graphite into a phenol resin. SOLUTION: As resin material, a phenol resin to which aromatic polyamide fiber, nonlinear inorganic filler and graphite are blended is used. The ratios to be added and kneaded to the phenol resin which is a base resin are set to the aromatic polyamide fiber: 15-25wt.%, the nonlinear inorganic filler: 5-20wt.%, and the graphite: 5-20wt.%, whereby wear resistance can be improved to stabilize frictional coefficient more. Thus, this material is applicable to a belt guide member (power transmitting member) as an eccentric ring 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a power transmission member such as a pulley.

[0002]

2. Description of the Related Art In recent years, there has been provided a variable speed pulley capable of changing a contact diameter of a belt. In this variable speed pulley, a V belt is directly wound around a V groove of the pulley. There are a type in which a flat belt is wound around an eccentric ring fitted in a V groove of a pulley, and a type in which a flat belt is wound.

In the latter case, torque is transmitted between the eccentric ring and the member forming the V-groove. However, since the area of the contact portion between the two is small, the surface pressure becomes extremely high. Further, in the contact portion, there is a very complicated contact state in which a rolling motion for transmitting torque and a sliding motion for eccentricity are mixed. On the other hand, conventionally, since metal has been used as a material for forming the eccentric ring, there have been problems such as seizure and abrasion of members forming the V-groove.

Therefore, it is conceivable to use a resin for the eccentric ring. However, when a general resin is used, the wear of the eccentric ring increases and the friction becomes unstable, resulting in a stable transmission torque. In some cases, the contact portion may be melted. In other words,
The resin molded body used for the eccentric ring must have a moderate aggressiveness against the mating member despite its excellent abrasion resistance, and have a stable moderate coefficient of friction regardless of the temperature. Will be required.

In recent years, as automobile parts have been reduced in size and weight and cost has been reduced, pulleys made of resin have been replaced by resin-made pulleys. The pulley has the same problem as the eccentric ring. An object of the present invention is to provide a power transmission member made of resin which is hard to be worn, has low aggressiveness to a counterpart material, and has a moderate friction coefficient which is stable in temperature.

[0006]

In order to solve the above-mentioned problems, the present invention is characterized in that a resin material in which an aromatic polyamide fiber, a nonlinear inorganic filler and graphite are mixed with a phenol resin is molded. Things.
Phenolic resins have the advantage of being excellent in heat resistance and rigidity and not melting and softening even at high temperatures, but are difficult to use in places where they are slippery and have a very high friction coefficient due to their inherent friction. Therefore, aromatic polyamide fibers and a nonlinear inorganic filler were used as a reinforcing material to improve the brittleness of the phenolic resin, and graphite was used as a solid lubricant to improve the slidability.

The above aromatic polyamide fibers not only contribute to the improvement of mechanical strength as a reinforcing material, but also exert a great effect on the improvement of abrasion resistance. The effect of abrading the mating member as seen can be small. As aromatic polyamide fibers,
Examples include Kevlar and Nomex (trade names, manufactured by DuPont), and Conex (trade name, manufactured by Teijin Limited). If the content of the aromatic polyamide fiber in the resin material is less than 15% by weight, there is a possibility that cracks may occur due to insufficient strength, and if it exceeds 25% by weight, the material becomes too hard and wears the mating member. , Preferably in the range of 15 to 25% by weight.

The above-mentioned nonlinear inorganic filler includes at least one selected from the group consisting of calcium carbonate, magnesium carbonate, silica powder, talc, clay, alumina, mica and gypsum. When the content of the nonlinear inorganic filler in the resin material is less than 5% by weight, the friction increases, and when the content is more than 20% by weight, the material becomes brittle. In particular, if the above-mentioned nonlinear inorganic filler is talc,
This is preferable in that the frictional force can be easily adjusted.

As the graphite used as an additive, there is, for example, CPB30 (Chuo-Graphite Graphite Works). If the content of graphite with respect to the resin material is less than 5% by weight, the sliding becomes poor, and if it exceeds 20% by weight, it becomes brittle, so that it is preferably in the range of 5 to 20% by weight.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a molding resin was prepared by adding and kneading an aromatic polyamide fiber, a nonlinear inorganic filler, and graphite at the following ratios to a phenol resin as a base resin.

Then, the molding resin is molded, and FIG.
An eccentric ring 1 as a power transmission member applied to the variable speed pulley A as shown in FIG. The eccentric ring 1 has an annular shape with a substantially trapezoidal cross section, and a flat belt B
To form a power transmission surface 1a. On this transmission surface 1a,
A plurality of concave grooves 1b meshing with the flat belt side are formed along the circumferential direction. This eccentric ring 1 has a V section defined between a pair of V-groove forming bodies 2 and 3 whose distance between them can be adjusted.
It is fitted in the groove 4. The tapered surfaces 1b and 1c formed on both circumferential side surfaces of the eccentric ring 1 are in contact with the inclined surfaces 2a and 3a of the V-groove formed bodies 2 and 3, respectively. The tapered surfaces 1b and 1c are portions where a very complicated contact state in which rolling motion for transmitting torque and sliding motion for eccentricity coexist exists.

In the above-mentioned variable speed pulley A, screw portions 6 and 7 having opposite pitches and having the same pitch are formed around a cylindrical rotary shaft 5 driven by the engine. V above
The groove forming bodies 2 and 3 are screw-fitted to the screw portions 6 and 7, respectively, and the V-groove forming bodies 2 and 3 are integrally rotatably connected to each other by concave and convex fitting. 8 is V
This is a disc spring that urges the groove forming bodies 2 and 3 in a direction approaching each other. In this variable speed pulley A, the eccentric ring 1 is moved along the axis 5a of the rotating shaft 5 by increasing the tension of the belt.
And the contact diameter of the belt is changed.

The above-mentioned aromatic polyamide fiber not only contributes to the improvement of mechanical strength as a reinforcing material, but also exerts a great effect on the improvement of abrasion resistance. The effect of abrading the mating member as seen can be small. The content of the aromatic polyamide fiber in the resin material is preferably in the range of 15 to 25% by weight. This is because if it is less than 15% by weight, cracks may occur due to insufficient strength, and if it exceeds 25% by weight, it becomes too hard and wears the mating member. Examples of the aromatic polyamide include Kevlar and Nomex (trade name) manufactured by DuPont, and Conex (trade name) manufactured by Teijin Limited.

The non-linear inorganic filler includes at least one selected from the group consisting of calcium carbonate, magnesium carbonate, silica powder, talc, clay, alumina, mica and gypsum. The content ratio of the nonlinear inorganic filler in the resin material is preferably in the range of 5 to 20% by weight. This is because if it is less than 5% by weight, the friction increases, and if it exceeds 20% by weight, it becomes brittle. In particular, if the above-mentioned nonlinear inorganic filler is talc, it is preferable in that the frictional force can be easily adjusted.

Examples of graphite used as an additive for improving slidability and abrasion resistance include, for example, C
There is PB30 (Medium Super Graphite Industrial Plant). The content ratio of graphite to the resin material is preferably in the range of 5 to 20% by weight. This is because if the content is less than 5% by weight, the sliding becomes poor, and if it exceeds 20% by weight, the material becomes brittle.

In this embodiment, a resin material obtained by blending an aromatic polyamide fiber, a nonlinear inorganic filler, and graphite with a phenol resin is used.
Although the molded body itself is excellent in wear resistance, the aggressiveness to the mating member is moderate, and the molded body has a stable and appropriate friction coefficient regardless of the temperature. Therefore, it is suitable for application to a belt guide member (power transmission member) such as an eccentric ring. The mixing ratio of the aromatic polyamide fiber, the non-linear inorganic filler and the graphite to the phenol resin was 15 to 25% by weight of the aromatic polyamide fiber and 5 to 20% by weight of the non-linear inorganic filler.
By weight and graphite: in the range of 5 to 20% by weight, the wear resistance can be further improved, and the friction coefficient can be further stabilized.

In particular, when the non-linear inorganic filler is talc, it is easy to adjust the frictional force. In the above embodiment, the entire eccentric ring is made of resin.
As shown in (a), only the portion where the eccentric ring 10 contacts the slope of the V-groove of the variable speed pulley may be made of the resin 20, and the remaining portion may be made of the metal 30. FIG. 2 (b)
As shown in (1), a portion where the eccentric ring 10 contacts the flat belt and the slope of the V-groove may be made of the resin 20, and the remaining portion may be made of the metal 30. In the embodiments of FIGS. 2A and 2B, the resin 20 and the metal 30 may be bonded to each other using an adhesive, or may be bonded to each other by insert molding.

The present invention can be applied to general power transmission members such as pulleys and other belt guide members. In addition, various changes can be made within the scope of the present invention.

[0019]

Examples Nos. 1 to 3 and Comparative Examples 1 to 7 Novolac type phenolic resins as base resins
Various fillers were added and kneaded at the ratios shown in Table 1 to prepare a molding resin, and then the molding resin was molded.
3 and the eccentric rings of Comparative Examples 1 to 6 were obtained.

Examples 1 to 3 and Comparative Examples 1 and 2 were filled with aromatic polyamide fibers, graphite and talc. Comparative Example 3 is one filled with carbon fiber and graphite. Comparative Example 4 is a carbon fiber,
It is filled with graphite, PTFE and BP. Comparative Example 5 was filled with an aromatic polyamide fiber, graphite, talc, carbon fiber and PTFE. Comparative Example 6 was filled with carbon fiber, graphite and PTFE. Comparative Example 7 was filled with carbon fiber, aromatic polyamide fiber and molybdenum disulfide. In Table 1, the aromatic polyamide fiber is represented by aramid F, and the carbon fiber is represented by carbon F.

[0021]

[Table 1]

Using the eccentric rings of Examples 1 to 3 and Comparative Examples 1 to 6 as variable speed pulleys, evaluation tests were performed on wear resistance, sample temperature, coefficient of friction, aggressiveness against partner and vibration. The results shown in Table 1 were obtained. The test was performed by pressing the outer peripheral portions of two disks having different peripheral speeds to forcibly generate a slip at the contact point, and measuring the disk sample temperature, friction coefficient, and vibration. Further, the wear resistance of the disk and the aggressiveness of the partner were evaluated by measuring the amount of wear of the disk.

In the test results, the criterion for the abrasion resistance was ○ for no disk wear and × for wear.
Regarding the sample temperature, を indicates that the temperature was 60 ° C. or less, and X indicates that the temperature exceeded 60 ° C. The coefficient of friction is 0.2 to 0.1.
In the case of No. 4, there was no change, and in the other cases, it was marked as x. In the opponent aggressiveness, the case where there was no wear of the opponent disk was evaluated as ○, and the occurrence of wear was evaluated as x. In the case of vibration, the case where the vibration occurred was evaluated as x.

From the test results in Table 1, the following was found. 1) From the test results of Examples 1 to 3, the aramid fiber (aromatic polyamide fiber) is 15 to 25% by weight, the nonlinear inorganic filler is 5 to 20% by weight, and the graphite is 5 to 20% by weight.
, Good in all respects of abrasion resistance, sample temperature, coefficient of friction, aggressiveness to partner and vibration. 2) In Comparative Example 1, the eccentric ring was too hard due to the high content of aramid fiber of 30% by weight, and the opposing aggressiveness was large. In addition, the coefficient of friction was low because of only 3% by weight of graphite. Became large and the sample temperature rose, resulting in a failure. In addition, the talc was as large as 25% by weight, resulting in brittleness and insufficient strength. 3) In Comparative Example 2, abrasion was large because the aramid fiber was as small as 10% by weight, and the coefficient of friction was too small because graphite was as large as 25% by weight and talc was as small as 3% by weight. 4) In Comparative Example 3, although graphite is in a preferable range of 15% by weight, since carbon fiber is contained as a reinforcing material, the aggressiveness to the opponent is large, and since talc is not contained, the coefficient of friction is low. Too much. 5) In Comparative Example 4, although the graphite was in a preferable range of weight%, the aggressiveness to the opponent was high because the carbon fiber was contained. In addition, the friction coefficient was not good because talc was not contained. 6) In Comparative Example 5, although the aramid fiber, the graphite and the talc were each in the preferable ranges, the carbon fiber was included, so that the opponent aggressiveness was large. 7) In Comparative Example 6, although the graphite was included, a large amount of carbon fiber was included, so that the opponent aggressiveness was large. 8) In Comparative Example 7, although the aramid fiber was included, the aggressiveness to the opponent was high because the carbon fiber was included. In Comparative Example 7, the reason why the wear resistance was poor and the vibration was large is presumed to be that MoS ₂ had no effect as a solid lubricant. 9) Regarding PTFE, it is inferred from the results of Comparative Examples 4 to 6 that the effect on the stability of the friction coefficient is smaller than that of graphite. 10) Regarding BP, it is inferred from the results of Comparative Examples 4 and 6 that there is no effect as a friction modifier.

[0025]

As described above, in the present invention, as the resin material, a phenol resin mixed with an aromatic polyamide fiber, a nonlinear inorganic filler and graphite is used. Despite being excellent in abrasion, the aggression to the mating member is moderate,
Moreover, it has a stable and appropriate friction coefficient regardless of the temperature. Therefore, it is suitable for application to a power transmission member such as an eccentric ring.

The mixing ratio of the aromatic polyamide fiber, the nonlinear inorganic filler and the graphite to the phenolic resin is as follows: aromatic polyamide fiber: 15 to 25% by weight, nonlinear inorganic filler: 5 to 20% by weight, graphite: 5 ~ 2
When the content is in the range of 0% by weight, the wear resistance can be further improved, and the friction coefficient can be further stabilized. Especially,
If the non-linear inorganic filler is talc, it is easy to adjust the frictional force.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a variable speed pulley including an eccentric ring as a power transmission member according to an embodiment of the present invention.

FIGS. 2A and 2B are cross-sectional views of main parts of an eccentric ring according to another embodiment of the present invention.

[Explanation of symbols]

 1,10 Eccentric ring

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takahiro Hiraoka 1-71, Tokuan, Tsurumi-ku, Osaka City, Osaka Inside Starlight Industry Co., Ltd.

Claims (3)

[Claims] 1. A power transmission member formed by molding a resin material in which an aromatic polyamide fiber, a nonlinear inorganic filler, and graphite are blended with a phenol resin. 2. The resin material contains aromatic polyamide fiber, nonlinear inorganic filler and graphite in the following proportions: aromatic polyamide fiber: 15 to 25% by weight, nonlinear inorganic filler: 5 to 20% by weight, graphite: 5 The power transmission member according to claim 1, wherein the power transmission member is in a range of 20 to 20% by weight. 3. The power transmission member according to claim 1, wherein the non-linear inorganic filler is talc.