JP2007252176A - Mold motor and manufacturing method therefor, and molding die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a mold motor that is high in reliability without causing any failures resulting from an internal mold release agent, superior in insulation property, reduced in maintenance labor of mold die, high in productivity and low in cost. <P>SOLUTION: This mold motor has a stator, comprising at least a core 4, winding 2 and an insulator 3 integrally molded by a molding material that is constituted of unsaturated polyester. The molding material contains unsaturated polyester resin, a shrink-preventing material, a polymerizable monomer, aluminum hydroxide and a glass fiber as the essential components and will not mix with internal mold release agent. Furthermore, the integrally molded molding die 7 is provided with an insert 14 in an upper mold 8 and a lower mold 9 to allow venting, and the mold release member 12, composed of fluororesin dispersed nickel plating, is coated on the surface of the insert. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mold motor having high reliability and a method for manufacturing the same, and particularly to a molding material, a release member, and a molding die.

2. Description of the Related Art Conventionally, a method has been proposed in which a stator of a motor is formed integrally with a molding resin using an unsaturated polyester molding material (see, for example, Patent Document 1).
FIG. 1 shows the structure of another conventional molded motor. FIG. 1 is a longitudinal sectional view showing a stator portion of a conventional motor, and FIG. 2 is a transverse sectional view. In the figure, 1 is a stator, 2 is a winding, 3 is an insulator, 4 is a core, 5 is a molding material made of unsaturated polyester, and 6 is a core segment. The core 4 is a divided core, and a core segment 6 is manufactured by laminating a required number of core sheets, and an insulator 3 around which a winding 2 is wound is attached. These core segments are connected to each other, and are integrally molded with the molding material 5 so that they are fixed to each other to form the stator 1.
The molding material 5 is composed of an unsaturated polyester resin, a polymerizable monomer, a polymerization initiator, a filler, and the like, and an internal release material such as a stearic acid compound is added as an essential component in order to impart release properties.
FIG. 3 shows a molding die 7 for molding the stator 1 and schematically shows a cross section thereof. In the figure, 8 is an upper mold, 9 is a lower mold, 10 is a core, and 13 is a slide mold. JIS-SKD11 is used as the material of these mold parts. A nozzle 11 for pouring the molding material 5 is formed in the upper mold 8.
Next, a method for forming the stator 1 will be described.
As shown in FIG. 3, the stator 1 is temporarily assembled as a core 4 by connecting a core segment 6 to which a winding 2 and an insulator 3 are attached, and is set in a molding die 7. These are preheated to a molding temperature of 150 ° C., and then the molding material 5 is heated and pressurized and injected under molding conditions of about 150 ° C. and 50 MPa by an injection molding machine (not shown).
The molding material 5 passes through the nozzle 11 formed in the upper die, enters the molding die 7, enters a gap such as between the winding 2, the insulator 3 and the core segment 6, and spreads over the entire stator 1. So as to be filled. After injecting the molding material 5, it is held in a heated and pressurized state for about 10 minutes for curing. Thereafter, the upper die 8 is raised, and the slide die 13 is opened to the left and right while being divided into two, and the stator 1 is removed from the molding die 7. At this time, the stator 1 is removed from the molding die 7 because the molding material 5 contains a stearic acid compound as an internal mold release material. In this way, the stator 1 is obtained.
On the other hand, as a conventional technique for obtaining a high-quality molded motor without voids, several methods have been proposed in which degassing during molding is performed using a nest installed in a molding die (for example, Patent Document 2). 3).
These are performed in order to prevent the resin from being unfilled by providing a groove between the molding die and the insert so that the gas during molding is extracted from the gap.
JP 2001-231192 A Patent 3007184 JP-A-7-274454

However, the conventional molded motor has the following problems.
In order to release the stator from the molding die, it is essential to add a stearic acid compound to a molding material composed of an unsaturated polyester. Therefore, the molding material contains a stearic acid compound as an internal mold release material. When the motor is used, operates, and the temperature rises, there is a problem that the internal mold release material remaining in the molding material volatilizes and the inside of the motor is soiled.
Moreover, since it is a salt of an organic acid, it becomes a factor which reduces insulation. In some cases, the molding die is subjected to acid corrosion, which increases the production cost.
Since the polymerizable monomer compounded in the unsaturated polyester molding material is highly volatile, a part of it volatilizes and adheres to and solidifies on the release member on the surface of the molding die during molding. There was a problem of lowering the moldability.
The present invention has been made in view of such problems, and is highly reliable without defects caused by the internal mold release material, excellent in insulation, and reduces the maintenance work of the mold, thereby improving productivity. An object of the present invention is to provide a low-cost and low-cost molded motor and a manufacturing method thereof.

In order to solve the above problems, the present invention is configured as follows.
The invention according to claim 1 is a molded motor in which a stator composed of at least a core, a winding, and an insulator is integrally formed of a molding material made of unsaturated polyester, wherein the molding material is an unsaturated polyester resin. In addition, a shrinkage-preventing material, a polymerizable monomer, aluminum hydroxide, and glass fiber are essential components, and no internal mold release material is blended.
According to a second aspect of the present invention, a stator composed of at least a core, a winding, and an insulator is installed in a molding die, and a molding material composed of unsaturated polyester is poured into the molding die, so as to be integrated. In the molding motor manufacturing method for molding, the molding material does not contain an internal mold release material, and the inner surface of the molding die is coated with a mold release member made of fluorine resin-dispersed nickel plating. It is.
According to a third aspect of the present invention, the molding material contains an unsaturated polyester resin, a polymerization initiator, an anti-shrinkage material, a polymerizable monomer, aluminum hydroxide, and glass fiber as essential components.
According to a fourth aspect of the present invention, the release member has a fluororesin content of 10 to 35% by volume.
In a fifth aspect of the present invention, the film thickness of the release member is 10 to 30 μm.
The invention described in claim 6 has an upper die, a lower die, a core, and a nozzle for pouring a molding material, and a stator composed of at least a core, a winding, and an insulator is integrated with the molding material. In the molding die to be molded, the upper mold or the lower mold is provided with a nest so that gas can be vented, and the surface of the nest is coated with a release member made of a fluororesin-dispersed nickel plating. .
According to a seventh aspect of the present invention, the insert is attached to a mold part in a position perpendicular to the injection direction of the molding material and in a position where the molding material is finally filled. is there.
According to an eighth aspect of the present invention, the maximum width of the groove between the insert and the mold part is 0.01 to 0.05 mm.
The invention according to claim 9 is a molded motor manufactured using the molding motor mold according to claims 6 to 8.

According to the first aspect of the present invention, since the internal mold release material is not blended in the molding material of the unsaturated polyester, the internal mold release material volatilizes, and the reliability does not cause a problem caused by fouling the inside of the motor. High motor. Furthermore, since the essential components are specified, they are excellent in insulation, low vibration and heat dissipation.
According to the second aspect of the present invention, since the molding material made of unsaturated polyester not blended with the internal mold release material is used, the internal mold release material volatilizes and causes a problem caused by fouling the inside of the motor. It is possible to provide a highly reliable motor without any problems.
According to the invention described in claim 3, since an unsaturated polyester resin, an anti-shrinkage material, a polymerizable monomer, aluminum hydroxide, and glass fiber are essential components as a molding material, insulation, low vibration, and heat dissipation can be achieved. An excellent motor can be provided.
According to the invention described in claim 4, since the fluororesin content of the fluororesin-dispersed nickel plating, which is the mold release member of the molding die, is 10 to 35% by volume, the releasability at the time of stator molding becomes good. High-productivity and low-cost motors can be provided.
According to the invention described in claim 5, since the film thickness of the mold release member of the molding die is 10 to 30 μm, a motor with excellent dimensional accuracy can be provided.
According to the invention described in claim 6, since the polymerizable monomer can be effectively discharged, adhesion to the release member and solidification can be reduced. In addition, since the nest is covered with a release member, the nest and the molding material cannot be released from each other, and when the nest is soiled with the polymerizable monomer, cleaning after removal becomes easy. . For these reasons, the productivity of the molded motor can be improved.
According to the invention described in claim 7, since the insert is attached to the mold part at the position where the molding material is finally filled, the polymerizable monomer can be effectively discharged, and its adhesion, Solidification can also be reduced. From this, the productivity of the molded motor can be improved.
According to the invention described in claim 8, since the maximum width of the groove between the insert and the mold part is set to 0.01 to 0.05 mm, the molding material does not leak and only the polymerizable monomer is used. It can be discharged effectively. From this, the productivity of the molded motor can be improved.
According to invention of Claim 9, since it is a mold motor manufactured using the molding die for mold motors described in Claims 1-3, a low-cost mold motor can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 is a longitudinal sectional view of a stator of a molded motor showing Embodiment 1 of the present invention, FIG. 2 is a transverse sectional view thereof, and FIG. 3 is a sectional view showing a state in which the molded motor of the present invention is installed in a molding die. . Since both are the same as the conventional example, the description is omitted. The procedure for forming the stator 1 is also the same. However, as the molding material 5, unsaturated polyester resin (8 to 11 wt%), shrinkage prevention material (4 to 7 wt%), polymerizable monomer (8 to 10%), aluminum hydroxide (45 to 55 wt%), glass fiber (4-7 wt%) and other components composed of components such as extenders and additives are used, and injection molding or compression molding is used as the molding method.
The mold motor of the present invention is different from the conventional example in that an internal mold release material is not blended with a molding material made of unsaturated polyester, and the surface of the molding die 7 in contact with the molding material 5 is fluororesin-dispersed nickel plating. It is a point that is covered.
FIG. 4 schematically shows a cross section near the surface of the molding die 7. In the figure, 12 is a release member made of fluororesin dispersed nickel plating, 12b is fluororesin particles, and 12a is nickel plating.
The release member (fluorine resin dispersed nickel plating) 12 has a structure in which fluorine resin particles 12b such as sub-micron size PTFE (polytetrafluoroethylene) are uniformly dispersed in the nickel plating 12a. 12b exhibits releasability.
Regarding the dispersion amount of the fluororesin particles 12b in the release member 12, the larger the dispersion amount of the fluororesin particles 12b, the better the release property, but on the other hand, the wear resistance is inferior, and the release member 12 is worn away. Degradation of type is quick. On the other hand, when the dispersion amount of the fluororesin particles 12b is small, the wear resistance is excellent, but the releasability is poor. Therefore, it is necessary to determine the amount of dispersion of the fluororesin particles 12b in consideration of releasability and wear properties. Table 1 shows the amount of the fluororesin dispersed in the release member 12, the release property, and the wear property. In addition, about abrasion property, the number of shots that could be molded is shown.

When the dispersion amount of the fluororesin particles 12b was 40% by volume, although the mold release property was excellent, the mold release member 12 was worn and only 3,000 shots could be molded. On the other hand, when the dispersion amount of the fluororesin particles 12b is 5% by volume, the wear resistance is excellent, and up to 30,000 shots can be molded, but the releasability is poor and the stator 1 cannot be taken out from the molding die 7 well. Occurred frequently. When the dispersion amount of the fluororesin particles 12b was 10 to 35% by volume, the release property of the stator 1 was good, and 1 to 30,000 shots could be formed. Therefore, considering the productivity of the stator, the dispersion amount of the fluororesin particles 12b is preferably 10 to 35% by volume. In this case, a low-cost motor is obtained.
The film thickness of the release member 12 is preferably 10 to 30 μm. Thereby, it becomes a motor with excellent dimensional accuracy. This is because the release member 12 is worn out during repeated molding, and thus the dimensional change of the stator 1 becomes large if the release member 12 is thick.
Further, since the unsaturated polyester molding material 5 is composed of an anti-shrinkage material, a polymerizable monomer, aluminum hydroxide, and glass fiber, the insulation, low vibration, and heat dissipation of the motor can be improved.
As the molding method, high-productivity injection molding or compression molding is good, and a low-cost motor is obtained.

FIG. 5 is a sectional view of a molding die showing Example 2 of the present invention.
In the figure, 14 is a nest, 15 is a bolt, 16 is a groove, and 17 is a gas vent. The lower mold 9 includes a lower outer mold 9a and a lower inner mold 9b.
The present invention is different from the conventional example in that the lower inner mold 9b is provided with a nesting 14 having a fluorine resin dispersed nickel plating. The nests 14 are inserted into the lower inner mold 9b at two locations and fixed with bolts 16 respectively. FIG. 65 is an outline view showing details of the insert 14. The insert 14 includes a portion where a groove 16 for discharging a polymerizable monomer is formed, and a gas vent path 17 serving as a path for discharging the polymerizable monomer out of the molding die 7. The groove 16 has a shape obtained by D-cutting the side surface of the cylinder at eight places, and the thickness of the groove 16 is adjusted to 0.01 to 0.05 mm. This is because the molding material 5 is an unsaturated polyester molding material, and its viscosity is lower than that of a thermoplastic resin. Therefore, if the thickness is increased beyond this, the generation of burrs increases and the productivity decreases. On the other hand, if it is smaller than 0.01 mm, the effect of releasing the polymerizable monomer is almost lost. The groove portion of the insert 14 and the gas vent path 17 are also subjected to fluorine resin dispersed nickel plating. Thus, the molding material 5 does not stick to the insert 14 and can be easily removed and cleaned. The reason why the nest 14 is installed in the lower inner mold 9b is that the portion of the lower inner mold 9b is filled with the molding material 5 at the end of molding, so that the polymerizable monomer is easily collected. This is because the flow of the material 5 is small, and thus the place where the polymerizable monomer is most likely to adhere and solidify in the molding die 5.
In the case of the conventional molding die, the adhesion of the polymerizable monomer and the wiping and cleaning of the solidified product performed using a solvent such as thinner are required every about 100 shots. In some cases, this was reduced to about once every 1000 shots. Since the maintenance time can be reduced in this way, productivity can be improved, and the molded motor manufactured in this way is a low-cost motor.

The longitudinal cross-sectional view of the stator of the mold motor which shows Example 1 of this invention Cross-sectional view of FIG. Sectional drawing which shows the state which installed the mold motor in the molding die Enlarged cross-sectional schematic diagram showing the state of the surface of the molding die of the present invention Sectional drawing of the molding die which shows Example 2 of this invention Enlarged view of nesting in FIG.

Explanation of symbols

1 Stator 2 Winding 3 Insulator 4 Core 5 Molding Material (Unsaturated Polyester)
6 Core segment 7 Mold 8 Upper mold 9 Lower mold 9a Lower outer mold 9b Lower inner mold 10 Core 11 Nozzle 12 Mold release member (Fluorine resin dispersed nickel plating)
12b Fluororesin particles 12a Nickel plating 13 Slide mold 14 Nest 15 Bolt 16 Groove 17 Gas vent

Claims (9)

In a molded motor in which a stator composed of at least a core, a winding, and an insulator is integrally formed of a molding material made of unsaturated polyester,
The molding motor is characterized in that an unsaturated polyester resin, an anti-shrinkage material, a polymerizable monomer, aluminum hydroxide, and glass fiber are essential components, and an internal mold release material is not blended. In a molding motor manufacturing method in which a stator composed of at least a core, a winding, and an insulator is installed in a molding die, a molding material made of unsaturated polyester is poured into the molding die, and the molding is integrally molded.
The molding material does not contain an internal mold release material, and the inner surface of the mold is coated with a mold release member made of fluorine resin-dispersed nickel plating. .   The method for producing a molded motor according to claim 2, wherein the molding material contains an unsaturated polyester resin, an anti-shrinkage material, a polymerizable monomer, aluminum hydroxide, and glass fiber as essential components.   The method for manufacturing a molded motor according to claim 2, wherein the release member has a fluororesin content of 10 to 35% by volume.   The method for manufacturing a molded motor according to claim 2, wherein the release member has a thickness of 10 to 30 μm. In a molding die that has an upper die, a lower die, a core, and a nozzle for pouring a molding material, and integrally molds a stator composed of at least a core, a winding, and an insulator with the molding material,
A molding die characterized in that a nest is provided in the upper die or the lower die so that gas can be vented, and a release member made of fluorine resin-dispersed nickel plating is coated on the surface of the nest.   The said nest | insert is attached to the metal mold | die part in the position perpendicular | vertical to the injection direction of the said molding material, and the position where the said molding material is filled last. Molding mold.   8. The mold according to claim 7, wherein the maximum width of the groove between the insert and the mold part is 0.01 to 0.05 mm.   A molded motor manufactured using the molding die for a molded motor according to claim 6.

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