JP3402935B2 - Phenolic resin composition for commutator molding of motor and method for pelletizing phenolic resin composition for commutator molding of motor - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a phenol resin composition used for molding a commutator (commutator) of a motor and a pellet processing method of the phenol resin composition.

[0002]

2. Description of the Related Art Since a commutator of a motor is rotated at a high speed, importance is attached to the breaking strength at the time of high speed rotation. For this reason, the phenol resin composition used for molding the commutator is mixed with a large amount of glass fiber of about 70 to 80% by weight so that high rotational rupture strength can be obtained.

[0003]

However, when the glass fiber content is large in this way, the phenolic resin composition has a flaky or cotton-like property and is difficult to be molded into pellets. It was not handled well. In particular, commutators for starter motors of four-wheeled vehicles are required to have higher rotational rupture strength, so the amount of glass fiber compounded increases, and the molding material of the phenol resin composition becomes bulky (small bulk density). ), When molding the molding material with an injection molding device or preheating it with a plasticizing device, there is a risk that the hopper may fall off or the weighing stability may deteriorate, which is a serious problem in use. there were.

The present invention has been made in view of the above points, and a motor that can obtain high rotational rupture strength with a small amount of glass fiber and can be processed into pellets having a high bulk density for use. it is an object to provide a commutator molding phenol <br/> Lumpur resin composition and pellet processing methods commutator molding Fe <br/> Nord resin composition of the motor.

[0005]

Means for Solving the Problems A motor according to the present invention
A phenol resin composition for commutator molding comprises a phenol resin and a glass fiber treated with a phenol resin sizing agent and 0.5 to 2.5% by weight of the glass fiber of a coupling agent. To do. A pellet processing method of a motor resin commutator molding phenol resin composition according to the present invention is characterized in that the phenol resin composition is extruded into pellets while being kneaded by a twin-screw kneading extruder. In addition, the above-mentioned phenol resin composition is kneaded by a biaxial kneading roll and then pelletized.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. In the present invention, the phenol resin is not particularly limited, but a novolac type phenol resin is generally used. Further, it is preferable to use glass fibers having a diameter of 8 to 12 μm and a fiber length of 3 to 6 mm, and glass chopped strands can be used. And in the present invention, as the glass fiber,
The one treated with a coupling agent after being treated with a sizing agent is used.

The sizing agent is also referred to as a sizing agent, and is made by bundling glass fibers in units of several hundreds to facilitate handling and reduce the bulk. As the sizing agent, it is preferable to use the same phenol resin as the matrix resin, and when the matrix resin is a novolac type phenol resin, it is preferable to use the novolac type phenol resin also as the sizing agent. The treatment amount of the phenol resin sizing agent is not limited, but the treatment amount is preferably in the range of 0.05 to 0.15% by weight with respect to the glass fiber.

The coupling agent has a function of mediating the adhesion between the glass fiber and the matrix resin,
It is possible to use an aminosilane coupling agent or the like. Conventionally, the coupling agent is generally treated in a treatment amount of about 0.01 to 0.1% by weight with respect to the glass fiber, but in the present invention, it is 0.5 to 2 which is 10 times or more that of the coupling agent. The glass fiber is treated with a coupling agent in an amount of 0.5% by weight. When the amount of the coupling agent treated with respect to the glass fiber is less than 0.5% by weight, the effect of improving the bonding strength between the glass fiber and the matrix resin by the coupling agent is insufficient, and the glass fiber must be blended in a large amount. It is not possible to exert a predetermined reinforcing effect. Further, even if the amount of the coupling agent treated exceeds 2.5% by weight with respect to the glass fiber, the bonding strength between the glass fiber and the matrix resin by the coupling agent is no longer improved, which is economically disadvantageous.

The glass fiber treated with the phenol resin sizing agent and the coupling agent is mixed with the phenol resin, and if necessary, a curing agent, an inorganic filler,
The phenol resin composition according to the present invention can be obtained by adding a release agent or the like. Here, in the present invention, the glass fiber is treated with a phenol resin sizing agent having a good affinity with the matrix resin, and 0.5 to 2.
It has been treated with a coupling agent in an amount of 5% by weight and has a high bond strength of the glass fiber to the matrix phenolic resin. Therefore, it is possible to obtain a high reinforcing effect of the molded article by the glass fiber, and it is possible to maintain the rotational breaking strength of the commutator obtained by the molding high even if the amount of the glass fiber is reduced. As described above, the phenol resin composition of the present invention can reduce the blending amount of glass fiber. In the present invention, the blending amount of glass fiber is 62% based on the solid content of the phenol resin composition.
It is preferably set to be less than or equal to weight%. The lower limit of the blending amount of glass fiber is not particularly set, but in order to keep the rotational rupture strength of the commutator obtained by molding high, it is preferable to blend 55% by weight or more of glass fiber in the solid content of the phenol resin composition. preferable.

Next, a method of processing the above-prepared phenol resin composition into pellets will be described.
Pellet processing methods include a method of extruding into pellets while kneading a phenol resin composition with a twin-screw kneading extruder, and a method of pelletizing after kneading a phenol resin composition with a twin-screw kneading roll, first of which two A method of pelletizing after kneading with an axial kneading extruder will be described with reference to FIG.

In this case, first, the phenol resin composition is kneaded while being heated to 60 to 120 ° C. with a kneader such as a pressure kneader, and the phenol resin composition is kneaded until it melts into a clay state. Then, the kneaded clay-like material is supplied from the hopper 18 to the twin-screw kneading extruder 4, and is extruded while being kneaded by the twin-screws 5 arranged side by side and in parallel and pelletized by the pelletizer 6. The pelletizer 6 includes a die plate 16 provided with a large number of extrusion holes 15 attached to the head of the twin-screw kneading extruder 4, and a die plate 16
And a cutter 17 composed of a rotary blade provided on the front side of the die plate. The strand extruded in a udon shape from the extrusion hole 15 of the die plate 16 is cut by the cutter 17 to a predetermined size, and this is cut. The pellet A of the phenol resin molding material can be obtained by cooling.

Next, a method of kneading the phenol resin composition with a biaxial kneading roll and then pelletizing the same will be described with reference to FIGS. 2 and 3. The biaxial kneading roll 2 is formed by including a pair of front and rear rolls 2a and 2b, and the rolls 2a and 2b are rotationally driven in mutually opposite directions as indicated by arrows in the figure. Further, guide grooves 8a, 8b are spirally formed on the outer circumference of each roll 2a, 2b,
The guide grooves 8a and 8b are also formed in spirals in mutually opposite directions. A material feeder 9 is disposed above one end of the biaxial kneading roll 2, and the other end of the biaxial kneading roll 2 is in contact with the front roll 2a. A pelletizer 3 is provided which is driven to rotate in the opposite direction at the same rotational peripheral speed. The pelletizer 3 is formed by integrally forming a cylindrical molding drum 12 on the outer circumference of a disk 11 provided with a rotating shaft 10, and has a large number of molding holes 13, 13 penetrating the molding drum 12 in and out.
... has been drilled. A cutter 14 is arranged inside the molding drum 12 with the blade edge in contact with the inner circumference of the molding drum 12. The cutter 14 is fixed independently of the forming drum 12.

Then, after the phenol resin composition 1 is charged into the material feeder 9 and preliminarily kneaded by the material feeder 9, the resin composition 1 is continuously fed to one end of the biaxial kneading roll 2. To do. The resin composition 1 is supplied from above the biaxial kneading roll 2 between the front and rear rolls 2a and 2b, and the phenol resin composition 1 is supplied with the guide grooves 8a and 8b.
Due to the action, a relatively large lump is caught between the front and rear rolls 2a and 2b while receiving a strong compressive shearing action, and at this time, shear heat is generated and heating from the jackets inside the rolls 2a and 2b (about 50 to 130 ° C. (Preferably), the phenol resin composition 1 is melted and wound around the front roll 2a. Phenol resin composition 1 and roll 2 on the front side
In order to wind it around a, generally, the rotation speed of the front roll 2a is made slightly smaller than that of the rear roll 2b, and the temperature of the front roll 2a is made slightly higher than that of the rear roll 2b. I am doing it. The phenol resin composition 1 thus supplied to the biaxial kneading roll 2 is kneaded by the action of compression shearing between the rolls 2a and 2b, and is fed by the guide grooves 8a and 8b, so that the front roll Along the outer circumference of 2a, one end moves to the other end in the arrow direction.

The phenol resin composition 1 melt-softened and kneaded in this way continuously moves to the other end while being wound around the front roll 2a of the biaxial kneading roll 2. At this end of the biaxial kneading roll 2, the molding drum 12 of the pelletizer 3 is rotationally driven by contacting the outer circumference of the front roll 2a, so that the resin composition 1 reaching the end of the roll 2a is The resin composition 1 is compressed between the roll 2a and the molding drum 12 and extruded in a udon shape through the molding hole 13 of the molding drum 12, and thus the resin composition 1 extruded in a udon shape through the molding hole 13 is formed in the molding drum. It is cut by the cutter 14 with the rotation of 12,
It is discharged in the form of pellets. Then , the pellets A of the phenol resin composition can be obtained by supplying the pellets onto a cooling conveyor and cooling them.

In pelletizing the phenolic resin composition as described above, the phenolic resin composition according to the present invention can reduce the amount of glass fiber compounded as described above. the bulk density becomes high with can be easily processed into high irrefrangible pellet bulk density, in which the molding of Konmi <br/> tape data can be easily carried out by using this pellet.

[0016]

EXAMPLES Next, the present invention will be specifically described with reference to examples. (Example 1) The glass fiber was treated with a novolac-type phenolic resin sizing agent in an amount of 0.1% by weight based on the glass fiber, and an aminosilane coupling agent in an amount of 1.0% by weight based on the glass fiber. Which had a diameter of 10 μm and a fiber length of 3 mm.

Then, a phenol resin composition was prepared by mixing 60 parts by weight of this glass fiber, 4 parts by weight of hexamethylenetetramine and 1 part by weight of zinc stearate with 35 parts by weight of a novolac type phenol resin (molecular weight 820). . (Example 2) Using a glass fiber treated in the same manner as in Example 1, a novolac type phenol resin (molecular weight 820)
68 parts by weight of this glass fiber, 4 parts by weight of hexamethylenetetramine, and 1 part by weight of zinc stearate were mixed with 27 parts by weight of the glass fiber to prepare a phenol resin composition.

(Comparative Example 1) The glass fiber was treated with a novolac type phenolic resin sizing agent in an amount of 0.1% by weight based on the glass fiber, and the aminosilane was added in an amount of 0.1% by weight based on the glass fiber. A product having a diameter of 10 μm and a fiber length of 3 mm treated with a coupling agent was used.

Then, 60 parts by weight of this glass fiber, 4 parts by weight of hexamethylenetetramine and 1 part by weight of zinc stearate were mixed with 35 parts by weight of a novolac type phenol resin (molecular weight 820) to prepare a phenol resin composition. . (Comparative Example 2) Using a glass fiber treated in the same manner as in Comparative Example 1, a novolac type phenol resin (molecular weight 820)
68 parts by weight of this glass fiber, 4 parts by weight of hexamethylenetetramine, and 1 part by weight of zinc stearate were mixed with 27 parts by weight of the glass fiber to prepare a phenol resin composition.

The phenol resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were pelletized by using the twin-screw kneading extruder shown in FIG. 1, and the two-screw kneading rolls shown in FIGS. Pellets were obtained by using them to obtain pellets of the phenolic resin molding material (the pellets obtained by using the twin-screw kneading extruder in FIG. 1 were kneaded and extruded, and the pellets obtained by using the twin-screw kneading roll in FIGS. 2 and 3). Is called roll kneading pellets).

Bulk kneading extruded pellets obtained from the phenol resin compositions of Examples 1 and 2 and Comparative Examples 1 and 2 and roll kneading pellets were measured for bulk density. The results are shown in Table 1. Moreover, a commutator for a motor was produced by injection molding using the kneaded and extruded pellets and the roll kneaded pellets as a molding material, and the rotational breaking strength of the commutator was measured. The rotation breakdown test was performed by rotating the commutator and increasing the rotation speed at a rate of 1000 rpm / 10 seconds, and measuring the rotation speed when the breakage occurred. The results are shown in Table 1.

[0022]

[Table 1]

As can be seen from Table 1, in Comparative Examples 1 and 2 in which the treated amount of the coupling agent was 0.1% by weight, the compounding amount of the glass fiber was the same as in Comparative Example 1. If the amount is small, the rotational rupture strength is low, and in order to secure the rotational rupture strength, it is necessary to increase the glass fiber content as in Comparative Example 2. However, if the glass fiber content is increased in Comparative Example 2, The bulk density of the let was small. On the other hand, the treatment amount with the coupling agent is 0.5% by weight.
In those in which the first embodiment above, even with a reduced amount of glass fibers can be obtained a sufficient rotation breaking strength and were capable of obtaining a not large pellet bulk density. Example 2 has a high rotational rupture strength, but the bulk density of the pellets is small because the blending amount of glass fiber is large, and Example 1 is preferable.

[0024]

As described above, the motor of the present invention is
A phenol resin composition for molding a mitator is prepared by containing a phenol resin and a glass fiber treated with a phenol resin sizing agent and a coupling agent of 0.5 to 2.5% by weight of the glass fiber. Yes, the glass fiber is treated with a phenol resin sizing agent that has a good affinity with the matrix resin, and since it is treated with a coupling agent that is 10 times or more the conventional amount, the bond strength of the glass fiber to the matrix phenol resin is high. Is high, and the reinforcing effect of the glass fiber can be high, and the rotational breaking strength of the commutator can be kept high even if the compounding amount of the glass fiber is reduced.

In the present invention, the above-mentioned phenol resin composition is extruded into pellets while being kneaded by a twin-screw kneading extruder, or after the above-mentioned phenol resin composition is kneaded by a twin-screw kneading roll. The above-mentioned phenol resin can be formed into pellets, and since the above-mentioned phenol resin can reduce the blending amount of glass fibers, pellets having a high bulk density and being hard to break can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a twin-screw kneading extruder.

FIG. 2 is a perspective view of a biaxial kneading roll.

FIG. 3 is a partially cutaway plan view of a biaxial kneading roll.

[Explanation of symbols]

1 Phenolic resin composition 2 Biaxial kneading roll 4 twin-screw kneading extruder

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C08L 61/06 C08L 61/06 // B29K 61:04 B29K 61:04 105: 06 105: 06 (56) References 61-151261 (JP, A) JP-A 63-150345 (JP, A) JP-A 5-86260 (JP, A) JP-A 5-414 (JP, A) JP-A 55-28873 (JP, A) JP-A-59-45346 (JP, A) JP-A-6-81273 (JP, A) JP-A-6-80438 (JP, A) JP-A-3-59060 (JP, A) JP-A-61 -66742 (JP, A) JP-A-9-38963 (JP, A) JP-A-9-254152 (JP, A) JP-A-9-277254 (JP, A) JP-A-3-246011 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 61/04-61/16 H01R 39/04-39/06 WPI / L (QUESTEL)

Claims (3)

(57) [Claims] 1. A commutator for a motor, comprising a phenol resin and a glass fiber treated with a phenol resin sizing agent and 0.5 to 2.5% by weight of the glass fiber of a coupling agent. Molding phenolic resin composition. 2. A phenol resin composition for molding commutator for motor, wherein the phenol resin composition of claim 1 is extruded into pellets while being kneaded by a twin-screw kneading extruder. Pellet processing method. 3. A method for pelletizing a phenol resin composition for motor commutator molding, which comprises kneading the phenol resin composition of claim 1 with a biaxial kneading roll and then pelletizing the kneaded product.