JPH10220562A - Resin pulley - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin pulley excellent in circularity and prevented from being damaged by temperature change by making a resin part contain a specific quantity of a filler in the resin pulley formed of a rolling bearing and the resin part integrally formed around the rolling bearing. SOLUTION: A resin pulley used to drive auxiliary machinery mounted on an automobile is composed of a rolling bearing 1 and a resin part 2 formed integrally with the rolling bearing 1 around the rolling bearing 1. This resin part 2 has a large number of ribs 7 formed at a disc part 6 formed between inner diameter and outer diameter cylindrical parts 3, 5, and fused resin is poured in a large number of gates formed at the inner diameter cylindrical part 3 to manufacture the resin pulley. In this case, the resin part 2 contains a filler at the content ratio of 50-65wt.%. The filler is not particularly limited, but a fiber group filler or a granular filler is used. Glass fiber or the like is used as the fiber group filler, and silica grain or the like is used as the granular filler.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin pulley, and more particularly, to a resin pulley used as a tensioner for driving belts and other belts of accessories mounted on an automobile or as an idler pulley. .

[0002]

2. Description of the Related Art Conventionally, a resin pulley formed by integrally molding a resin on the outer periphery of a rolling bearing has been adopted as a pulley for guiding a belt for driving auxiliary equipment of an automobile.

In this type of resin pulley, a rolling bearing is arranged at a predetermined position in an injection molding die, and a space defined between the outer peripheral portion of the rolling bearing and the injection molding die. It is manufactured by pouring a molten resin into a part and performing injection molding.

[0004] In the resin pulley, improvement of molding accuracy of an outer peripheral portion for guiding a belt is considered to be most important in terms of quality, and when the roundness is poor due to poor molding accuracy of the outer peripheral portion. At the time of driving, vibrations and abnormal sounds caused by the belt run-out occur.

Therefore, as a technique for increasing the roundness, the location of a gate (pinpoint gate) into which the molten resin flows during injection molding is devised to control the flow of the molten resin into the mold. On the other hand, as a resin material used for molding, reinforced nylon 66, reinforced nylon 610, reinforced nylon 612 filled with about 15 to 40% by weight of reinforcing fibers such as glass fiber, or a composite material of polyphenylene sulfide and mineral is used. A resin pulley using a polyamide resin such as 6-nylon, 66-nylon, 11-nylon, or 12-nylon containing 43% glass fiber as a reinforcing glass fiber has been proposed (Japanese Patent Laid-Open No. 7-6).
3249, JP-A-8-4883).

[0006]

However, since the conventional resin pulley is manufactured by injection molding as described above, molding shrinkage occurs due to a phase change when cooling and solidifying from a high temperature state to normal temperature. Since the roundness (outer diameter cylindricity) of the resin pulley that guides the belt is deteriorated due to the molding shrinkage, the conventional resin pulley described above is not yet sufficient as a countermeasure against occurrence of belt vibration and abnormal noise. There was a problem.

In the conventional resin pulley described above, since the above-described molding shrinkage occurs, stress remains in the contact portion between the resin portion and the rolling bearing in the tangential direction of the outer ring outer periphery of the rolling bearing. Is different from the linear expansion coefficient of the metal constituting the rolling bearing, that is, since the linear expansion coefficient of the resin is much larger than the linear expansion coefficient of the metal, the manufactured resin pulley has a low temperature atmosphere. When exposed to water, there is a problem that the stress increases, which results in damage to the resin.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a resin pulley which is excellent in roundness and does not break even with a change in temperature.

[0009]

In order to achieve the above object, a resin pulley according to the present invention comprises a rolling bearing and a resin portion formed around the rolling bearing and integrally with the rolling bearing. In the resin pulley, a filler is contained in the resin portion, and the content of the filler is expressed as weight%.
And 50 to 65%.

[0010]

Next, embodiments of the present invention will be described in detail.

FIG. 1 is a front view showing an embodiment of a resin pulley according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.

1 and 2, the resin pulley includes a rolling bearing 1 and a resin portion 2 formed around the rolling bearing 1 and integrally with the rolling bearing.

More specifically, the resin portion 2 includes an inner cylindrical portion 3 fixed to the outer ring of the rolling bearing 1, an outer cylindrical portion 5 having a belt guide surface 4, an outer cylindrical portion 5, and the inner cylindrical portion 5. And a disk portion 6 formed between the cylindrical portion 3 and a plurality of ribs 7 formed radially on the disk portion 6.
A large number of gates 8 are formed on the inner diameter cylindrical portion 3 at regular intervals with a predetermined pitch circle.
The molten resin is poured into the resin, and the present resin pulley is manufactured by injection molding.

The resin portion 2 contains a filler having a content of 50 to 65% by weight in addition to the resin material.

That is, in the resin pulley obtained by injection molding as described above, in order to suppress the generation of vibration due to the runout of the belt during driving and to reduce noise, an outer diameter cylindrical portion for guiding the belt is provided. 5 is required to have good circularity (pulley outer diameter cylindricity).

Therefore, as a result of earnest research by the present applicant,
It has been found that the roundness, that is, the accuracy of the outer cylindrical portion 5 is substantially proportional to the content of the filler, and that the content of the filler and the molding shrinkage that shrinks during molding are correlated.

That is, molding shrinkage is mainly caused by volume shrinkage caused by a phase change when the resin material is cooled from a high temperature near the melting temperature to room temperature.
It has been found that the inclusion of a filler other than the resin material in the resin portion 2 has a reinforcing effect on the filler, and as a result, it is possible to suppress shrinkage of the resin material and improve molding accuracy.

Next, the content of the filler is adjusted to 50% by weight.
The critical significance of ~ 65% will be described.

As described above, when the filler is contained in the resin part 2, the molding accuracy can be improved.
If the content is less than 0% by weight, the reinforcing effect of the filler is insufficient and the molding accuracy is deteriorated, and the outer diameter cylindricity of the pulley is significantly deteriorated. Therefore, the content is required to be at least 50% or more.

On the other hand, when the content of the filler exceeds 65%, the fluidity during injection molding is reduced, and the orientation and distortion in the weld portion formed between the gates 8 are increased, resulting in an annular tension. The strength is reduced and the heat cycle property is deteriorated. In particular, in this case, there is a possibility that a kind of stress concentration occurs, the strength of the weld portion is reduced, and the resin portion 2 is broken.

Therefore, in the present embodiment, the content of the filler is limited to 50 to 65% by weight. That is, the resin pulley having a filler content of 50 to 65% has a pulley outer diameter cylindricity of 40 μm or less and a molding shrinkage of 7.4 × 1.
0 becomes ^-3, also annular tensile strength becomes 960kgf / cm ^2, excellent roundness, and also becomes excellent in mechanical strength not to damage to temperature changes. In order to further satisfy both the roundness and the mechanical strength,
Pulley outer diameter cylindricity is 40 μm or less, molding shrinkage is 7.5
× 10 ^-3 or less, is preferably annular tensile strength of 960kgf / cm ² or more, the content of the filler for the 50
65% is preferred.

As the resin material, linear polyphenylene sulfide (hereinafter referred to as “L-PPS”) having excellent toughness is used.
), 66 nylon, 46 nylon, or branched polyphenylene sulfide (PPS).

As the filler, a fibrous filler or a particulate filler can be used. Specifically, glass fibers, carbon fibers, aramid fibers, and calcium titanate whiskers can be used as the fibrous filler, and silica (SiO ₂ ) or alumina (Al ₂ O) can be used as the particulate filler. ₃ ) Particles of calcium carbonate (CaC)
O ₃ ), talc, mica, graphite, metal powder and the like can be used. Further, the filler may be used alone, but when a fibrous filler and a particulate filler are combined, anisotropy of the resin due to molding shrinkage is suppressed, and mechanical It is preferable to use a combination of a fibrous filler and a particulate filler since the fiber filler can maintain an appropriate strength.

It is considered that there may be other resin materials and fillers that can be used, but a heat-resistant resin material is required for use in driving auxiliary equipment of an automobile. It is preferable that the temperature index specified in UL standard (long-term heat resistance) is at least 100 ° C. or more.

When used for guiding a belt rotating at a high speed or for a tensioner, it is necessary to efficiently radiate frictional heat generated between the belt and the resin portion 2 and heat generated from the rolling bearing 1. Therefore, it is preferable to use a carbon-based filler having a high thermal conductivity, a ceramic-based filler such as alumina, and a metal-based filler. In order to improve the adhesion between the filler and the resin material, silane coupling is appropriately performed. It is also preferable to add an additive such as an agent.

[0026]

Next, embodiments of the present invention will be described specifically.

[First Embodiment] In the first embodiment, L-PPS (trade name "Fortron KP") is used as a resin material.
S "; Kureha Chemical Industry Co., Ltd.), and as a filler, glass fiber (trade name" FES Grade "; Fuji Fiberglass Co., Ltd.); silica (trade name" Nipseal "; Nippon Silica Industry Co., Ltd.) Co., Ltd.) and calcium carbonate (trade name "Softon"; manufactured by Bihoku Powder Chemical Industry Co., Ltd.). That is, after measuring a predetermined amount of L-PPS, glass fiber, silica and calcium carbonate, these resin materials and fillers are mixed with a Henschel mixer to produce a mixed powder, and then the mixed powder is subjected to a twin-screw extruder ( Ikegai Iron Works Co., Ltd.
And kneaded and granulated under predetermined conditions to obtain a pellet-shaped resin composition.

Next, a resin pulley molding die (hereinafter, referred to as a die).
Abbreviated simply as “mold”. ) Is mounted on an injection molding machine, the mold is opened, the preheated rolling bearing is mounted at a predetermined position on the mold, and then the mold is clamped. Thereafter, the rolling bearing is formed between the outer ring of the rolling bearing and the mold. The molten resin composition is injected into a space to be formed. Then, after cooling and solidifying the molten resin composition, the mold was opened, and the molded product was taken out to obtain a resin pulley.

The molding conditions in the first embodiment are as follows.

Resin melting temperature (° C.): 310-325 Mold temperature (° C.): 140-150 Injection pressure (MPa): 90-120 Next, the resin pulley thus obtained is
Pulley outer diameter cylindricity, noise, heat cycle test, molding shrinkage, and ring tensile strength were measured.

Table 1 shows the results of measurement of the composition of each resin material and filler, and the cylindricity of the outer diameter of the pulley. Example 1
4 to 4 show the measurement results of the resin pulley in which the weight% of the filler was 50 to 65%, and Comparative Examples 51 and 52 show the resin pulleys in which the weight% of the filler was out of the range of 50 to 65%. 2 shows the measurement results.

[0032]

[Table 1] Next, a method of measuring the above-described pulley outer diameter cylindricity, noise, heat cycle test, molding shrinkage, and annular tensile strength will be described.

Pulley Outer Diameter Cylindricity To evaluate the roundness of the manufactured resin pulley, the pulley outer diameter cylindricity of Examples 1-4 and Comparative Examples 51 and 52 was measured. Specifically, as shown in FIG. 3, the shape of the belt guide surface of the resin pulley was measured, and the outer diameter cylindricity P of the pulley was calculated by Expression (1).

P = (D−d) / 2 (1) where D is the circumscribed circle diameter D of the resin pulley, and d is the inscribed circle diameter of the resin pulley.

Noise The resin pulleys of Examples 1 to 4 and Comparative Examples 51 and 52 were rotated at a rotation speed of 8000 rpm, and the run-out and noise state of the belt at that time were observed. The belt deflection was evaluated by visual recognition, and the noise state was judged and evaluated by hearing.

Heat cycle test The resin pulleys of Examples 1 to 4 and Comparative Examples 51 and 52 were put in a thermostat, and subjected to the heat cycle shown in FIG.
One cycle between 20 and 120 ° C. is defined as 2 cycles.
This was repeated 0 times to observe the appearance of the resin pulley. That is, one cycle is 8 hours, the temperature of the constant temperature bath is set to −20 ° C. for the first 2 hours, then the temperature of the constant temperature bath is gradually raised to 120 ° C., and then the temperature of the constant temperature bath is reduced to 12 ° C. for 2 hours.
After maintaining at 0 ° C., the temperature of the thermostat is gradually cooled to −20 ° C. After repeating such a cycle 20 times, the appearance of the resin pulley as a test product was observed.
That is, whether or not cracks (cracks) occurred in the resin pulley was examined, and the quality of the product was determined based on the presence or absence of the cracks.

Molding Shrinkage In order to measure the molding shrinkage x of the injection-molded resin,
A resin cylinder as shown in FIG. 5 was manufactured. That is, a resin composition having each composition shown in Table 1 was injection-molded,
The resin cylinder 11 having the gates 12 was produced, and the molding shrinkage x was calculated based on the mathematical formula (2).

X = ((T−t) / T) × 1000 (2) where T is the outer diameter of the core pin of the mold, and t is the inner diameter of the resin cylinder.

Ring Tensile Strength As shown in FIGS. 6 and 7, the first and second tensile jigs 13a and 13b having an L-shaped cross section and divided into two parts were used to measure the molding shrinkage. The first tension jig 13a is inserted into the inner diameter portion of the cylindrical body 11 and
The tensile jigs 13b were respectively pulled in the direction of arrow F, and the breaking strength of the resin cylinder 11 was measured to obtain an annular tensile strength.
Since the welded portion 14 formed between the gates 12 is the weakest part, the resin cylindrical body 11 faces the opposing surfaces 1 of the first and second tensile jigs 13a and 13b.
The resin cylinder 11 was set so that the weld portions 5a and 15b and the weld portion 14 were aligned in a horizontal direction, and the breaking strength of the weld portion 14 was measured.

As is clear from Table 1, as the content of the filler increases, good results can be obtained in the outer diameter of the pulley and in the molding shrinkage. It can be seen that there is also a correlation with the tensile strength. And since the content rate of the filler of Comparative Example 51 is as high as 67%,
Although the pulley outer diameter cylindricity was as good as 9 μm, a good result was obtained, but the ring tensile strength was reduced to 840 kgf / cm ^2, and cracks were observed in the heat cycle test. This is considered to be due to the fact that the orientation and distortion in the weld portion 14 are increased because the content of the filler is too high.
In Comparative Example 52, the filler was as low as 45%, so that good results were obtained in the ring tensile strength and the heat cycle test. However, since the reinforcing effect of the filler was insufficient, the molding shrinkage was 8%. 0.9 × 10 ^-3 and pulley outer diameter cylindricity is 9
The roundness was deteriorated to 7 μm, and the belt ran violently during driving, resulting in deterioration of the noise state.

On the other hand, in Examples 1 to 4, since the content of the filler was in the range of 50 to 65% by weight, good results were obtained in any of the noise state, the annular tensile strength, and the heat cycle test. The result was obtained. Also, from Table 1, at least the outer diameter cylindricity of the pulley is 40 μm or less, and the molding shrinkage is 7.
It can be seen that a resin pulley excellent in roundness and not damaged even by a change in temperature can be obtained when it is 4 × 10 ⁻³ or less.

The resin shrinkage stress .sigma.p occurs during molding, and the temperature after injection is determined by the difference between the linear expansion coefficient .alpha.m of the metal (for example, SUJ2) rolling bearing and the linear expansion coefficient .alpha.p of the resin forming the resin portion. When lowered, a temperature difference stress σT is generated. It is understood that the resin pulley is broken when the total stress σ obtained by adding the contraction stress σp and the temperature difference stress σT exceeds the ring tensile strength.

Therefore, the applicant of the present application prepared a dumbbell-type tensile test piece (JIS No. 1) using the resin compositions having the component compositions of Example 4 and Comparative Example 51, and manufactured it by Shimadzu Corporation. The tensile modulus of elasticity Ep was measured using an autograph, a small piece was cut out from the tensile test piece, and the linear expansion coefficient αp of the resin was measured by TMA manufactured by Seiko Electronics Co., Ltd. 4) and (5), the contraction stress σp, the temperature difference stress σT, and the total stress σ were calculated, respectively.

Σp = (x / (1000−x)) × Ep (3) σT = ΔT × (αp−αm) × Ep (4) σ = σp + σT (5) Here, ΔT is the value at the time of injection molding. And the temperature after cooling and solidification.

Table 2 shows the measurement results of various stresses and the like.

[0046]

[Table 2] From Table 2, the total stress σ of Example 4 is 738 kgf / cm ²
The total stress σ of Comparative Example 51 is calculated to be 729 kgf / cm ² . Comparative Example 51 having an annular tensile strength of 840 kgf / cm ²
The total stress σ can be almost estimated from the fact that is broken.

[Second embodiment] 46 nylon as a resin material (trade name "Teijin Nylon 46"; Teijin Limited)
Made of glass fiber (trade name "F")
ES grade "; manufactured by Fuji Fiber Glass Co., Ltd.), silica (trade name" Nipsil "; Nippon Silica Industry Co., Ltd.)
) And calcium carbonate (trade name "Softon"; manufactured by Bihoku Powder Chemical Industry Co., Ltd.), and in the same manner as in the first embodiment, a resin composition is obtained and then injection molded to form a resin pulley. Manufactured.

The molding conditions in the second embodiment are as follows.

Resin melting temperature (° C.): 315 to 325 Mold temperature (° C.): 120 to 140 Injection pressure (MPa): 120 to 140 Next, with respect to the resin pulley thus obtained,
According to the same method as that of the first embodiment, pulley outer diameter cylindricity,
The noise, heat cycle test, molding shrinkage, and annular tensile strength were measured.

Table 3 shows the results of measurement of the composition of each resin material and filler, and the cylindricity of the outer diameter of the pulley. Examples 11 to
14 shows the measurement results of the resin pulley in which the weight% of the filler is 50 to 65%, and Comparative Examples 61 and 62 show the measurement results of the resin pulley in which the weight% of the filler is out of the range of 50 to 65%. The measurement results are shown.

[0051]

[Table 3] In Table 3, in Comparative Example 61, the content of the filler was as high as 67%, and the pulley outer diameter cylindricity was as good as 26 μm, which was a good result. However, the same reason as described in the first example was used. From the results, the annular tensile strength decreased to 950 kgf / cm ^2, and cracks were observed in the heat cycle test. In Comparative Example 62, since the filler was as low as 45%, good results were obtained in the ring tensile strength and the heat cycle test.
Due to the insufficient reinforcing effect of the filler, the roundness of the pulley outer diameter was 60 μm, and the roundness was deteriorated, resulting in deterioration of the noise state.

On the other hand, in Examples 11 to 14, since the content of the filler was in the range of 50 to 65% by weight, satisfactory measurement results were obtained.

[Third Embodiment] Nylon 66 as a resin material (trade name "Ultramid" A4H grade; manufactured by BSF Engineering Plastics Co., Ltd.)
And glass fiber (trade name “FES
Grade "; manufactured by Fuji Fiber Glass Co., Ltd.), silica (trade name" Nipseal "; manufactured by Nippon Silica Industry Co., Ltd.)
Using calcium carbonate (trade name “Softon”; manufactured by Bihoku Powder Chemical Industry Co., Ltd.), a resin composition is obtained as in the first and second examples, and then injection molding is performed to manufacture a resin pulley. did.

The molding conditions of the third embodiment are as follows.

Resin melting temperature (° C.): 290 to 305 Mold temperature (° C.): 90 to 100 Injection pressure (MPa): 100 to 110 Next, with respect to the resin pulley thus obtained,
According to the same method as that of the first embodiment, pulley outer diameter cylindricity,
The noise, heat cycle test, molding shrinkage, and annular tensile strength were measured.

Table 4 shows the results of measurement of the composition of each resin material and filler and the cylindricity of the outer diameter of the pulley. Examples 21 to
24 shows the measurement results of the resin pulley in which the weight% of the filler is 50 to 65%, and Comparative Examples 71 and 72 show the measurement results of the resin pulley in which the weight% of the filler is out of the range of 50 to 65%. The measurement results are shown.

[0057]

[Table 4] In Table 4, in Comparative Example 71, the content of the filler was as high as 67%, and the pulley outer diameter cylindricity was 18 μm, which was a good result. However, the same reason as described in the first example was used. As a result, the ring tensile strength decreased to 890 kgf / cm ^2, and cracks were observed in the heat cycle test. In Comparative Example 72, since the filler was as low as 45%, good results were obtained in the ring tensile strength and the heat cycle test.
Since the reinforcing effect of the filler was insufficient, the roundness of the outer diameter of the pulley was 53 μm and the roundness was deteriorated, resulting in deterioration of the noise state.

On the other hand, in Examples 21 to 24, since the content of the filler was in the range of 50 to 65% by weight, satisfactory results were obtained for all the measurement results.

[Fourth Embodiment] As a resin material, L-PP
S (trade name "Fortron KPS"; manufactured by Kureha Chemical Industry Co., Ltd.), and as a filler, carbon fiber (trade name "Renoves"; manufactured by Osaka Gas Co., Ltd.), alumina (A
Using S grade (manufactured by Showa Denko KK), a resin pulley was prepared by injection molding after obtaining a resin composition in the same manner as in Examples 1 and 2.

The molding conditions of the fourth embodiment are as follows.

Resin melting temperature (° C.): 310 to 325 Mold temperature (° C.): 140 to 150 Injection pressure (MPa): 90 to 120 Next, with respect to the resin pulley thus obtained,
According to the same method as that of the first embodiment, pulley outer diameter cylindricity,
The noise, heat cycle test, molding shrinkage, and annular tensile strength were measured.

Table 5 shows the composition of each resin material and filler, and the results of measurement of the pulley outer diameter cylindricity and the like. Examples 31 to
34 shows the measurement result of the resin pulley in which the weight% of the filler is 50 to 65%, and Comparative Example 81 shows the measurement result of the resin pulley in which the weight% of the filler is out of the range of 50 to 65%. Is shown.

[0063]

[Table 5] In Table 5, in Comparative Example 81, the content of the filler was as high as 67%, so that the pulley outer diameter cylindricity was 6 μm, which was a good result. However, the same reason as described in the first example was used. , The tensile strength decreased to 880 kgf / cm ^2, and cracks occurred in the heat cycle test. In Comparative Example 82, the filler was as low as 40%, so that good results were obtained in the ring tensile strength and the heat cycle test. However, since the reinforcing effect of the filler was insufficient, the outer diameter cylindricity of the pulley was insufficient. Was 67 μm, which deteriorated the roundness and caused the noise state to deteriorate.

On the other hand, in Examples 31 to 33, since the content of the filler was in the range of 50 to 65% by weight, satisfactory results were obtained for all the measurement results.

FIGS. 8 to 10 are characteristic diagrams showing measurement results in the first to fourth embodiments. ○ indicates the measurement result of the first embodiment, □ indicates the measurement result of the second embodiment, △ indicates the measurement result of the third embodiment, and ◎ indicates the measurement result of the fourth embodiment.

As apparent from FIGS. 8 to 10, a resin pulley having a filling ratio of the resin portion 2 in the range of 50% to 65% has a pulley outer diameter cylindricity of 40 μm or less (FIG. 8).
In addition, the molding shrinkage becomes 7.4 × 10 ⁻³ or less (FIG. 9),
Further, the resin has an annular tensile strength of 960 kgf / cm ² or more (FIG. 10), can obtain good roundness, and has excellent reliability and durability without being damaged even by temperature change. It can be seen that the pulley made can be obtained.

[0067]

As described above in detail, the present invention relates to a resin pulley comprising a rolling bearing and a resin part formed integrally with the rolling bearing around the rolling bearing, wherein the filler is made of the resin. Parts, and the content of the filler is 50 to 65% by weight, so that it is excellent in roundness and excellent in mechanical strength which is not damaged by temperature change. A resin pulley with improved reliability and durability can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a resin pulley according to the present invention.

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

FIG. 3 is an explanatory diagram for explaining a method of measuring a pulley outer diameter cylindricity;

FIG. 4 is a time-temperature characteristic diagram showing test conditions of a heat cycle test.

FIG. 5 is a front view of a resin cylinder.

FIG. 6 is an explanatory diagram for explaining an annular tensile strength test of a resin cylinder.

FIG. 7 is a sectional view taken along the line BB of FIG. 6;

FIG. 8 is a characteristic diagram of pulley outer diameter cylindricity with respect to a filler content.

FIG. 9 is a characteristic diagram of a molding shrinkage ratio with respect to a filler content.

FIG. 10 is a characteristic diagram of ring tensile strength with respect to filler content.

[Explanation of symbols]

 1 rolling bearing 2 resin part

Continuation of the front page (72) Inventor Tadashi Kondo 1-5-50 Kugenuma Shinmei, Fujisawa-shi, Kanagawa Prefecture

Claims (1)

[Claims] 1. A resin pulley comprising a rolling bearing and a resin portion formed integrally with the rolling bearing around the rolling bearing, wherein a filler is contained in the resin portion and the filler is A resin pulley characterized in that the content of is 50 to 65% by weight.