JPS63114613A - Manufacture of armature for flat type motor - Google Patents

Abstract

PURPOSE:To obtain a uniform resin molded layer with neither scattering in the dimension of the outer diameter of an armature coil, which is inserted in the housing part of a runnerless mold, nor short spot by a structure wherein a resin flow path layer is provided on the outer peripheral part of a mold cavity. CONSTITUTION:The temperature of the resin in a manifold 5 is retained and controlled by means of cartridge heaters 7, which are divided into two systems. The resin, which has passed through the manifold 5, passes through annular gaps, each of which is formed between each of spires 1 and its casing 2, and stagnates temporarily. The temperature of the resin in said gap is retained and controlled by means of a heater built in the spire 1. The gate land part 1A of the resin is solidified by being cooled with molds 10 and 16 excluding at injection and injected in a housing part 12 by being melted with the heat generated by energizing the tip heater 3 of the spire just before injection in order to form a resin layer on an armature. At this time, since a resin flow path layer is provided at a site, which locates outside a gate formed by the spire 1 or the land part 1A, in the housing part 12, the resin injected in the housing part 12 flows along the armature so as to fill the housing part regardless of the scattering in the dimension of the outer diameter of the armature.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing an armature for a flat type motor in which a mold layer is formed on an armature coil made of thermoplastic resin.

[Conventional technology]

Conventionally, this type of flat motor armature is known, for example, as disclosed in Japanese Unexamined Patent Publication No. 57-52352.

The manufacturing method for this flat type motor armature consists of a resin filled in the resin flow path (runner) connecting the nozzle of the molding machine and the cavity of the mold, and a mold sealed with the resin filled in the cavity. There is a cold runner system in which the armature and the armature are cooled and solidified, the mold is opened, and the armature is discharged from the mold together with the armature.

[Problem that the invention seeks to solve]

However, this manufacturing method has problems such as the need for post-processing steps such as resin loss and treatment of the spool and runner parts, and cutting and finishing of the gate.

Recently, as a thermoplastic resin, it has been proposed to use polyphenylene sulfide resin (hereinafter referred to as PPS), which has high strength and high fluidity, for this type of armature, but this PPS has slightly low fluidity. Since there is a shortage, the defective rate due to filling is high.

On the other hand, with ultra-high fluidity PPS, although the defect rate due to filling is low, the mechanical strength of PPS is insufficient, and cracks occur in part when the shaft is fully sized, resulting in rejected products.

[Purpose of the invention]

The present invention has been made in order to solve the conventional problems, and its purpose is to provide a method for manufacturing an armature for a flat type motor that does not cause incomplete filling of thermoplastic resin.

[Means for solving problems]

The method for manufacturing an armature for a flat motor according to the present invention involves forming a large number of single coils into an annular shape in a superimposed manner using a forming jig, and then attaching the armature coils formed by connecting them to a commutator to the outer periphery of a mold cavity. A thermoplastic resin with high strength and ultra-high fluidity is injected into the housing part of the runnerless mold under ultra-low pressure by inserting it into the housing part of a runnerless mold with a resin flow path layer. However, the armature coil is configured to have a resin mold layer formed thereon.

[Action of the invention]

In the present invention, since the resin flow path layer is provided on the outer periphery of the mold cavity, there is no possibility of variation in the outer diameter of the armature coil inserted into the storage part of the runnerless mold, thereby preventing filling defects. A uniform resin mold layer can be obtained.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on the drawings.

Fig. 1 is a partially cutaway front view showing an apparatus for manufacturing an armature for a flat type motor according to the present invention, Fig. 2 is a cross-sectional view showing the main part thereof, and Fig. 3 is a cross-sectional view showing the main part thereof. A plan view of the molded armature for a flat type motor, and FIG. 4 is a sectional view thereof.

In the figure, 1 is three spears, which are fixed to a manifold 5. The casing 2 of each spear 1 is provided with a runner bushing 23. A tip heak 3 is provided at the tip of each spear 1. A lead wire 4 is taken out from the other end of the spear l protruding from the manifold 5. Further, the manifold 5 is formed with a cartridge heater insertion hole 6 into which a cartridge heater 7 is inserted, and a thermocouple insertion hole 8 into which a thermocouple 9 is inserted.

The three spears 1 are attached so that gates 32 are formed at equal intervals on the boss portion 31 of the resin-molded armature coil 30 as a product.

In addition, the spear 1 is equipped with a chimbu heater 3 for melting the solidified resin in the land rA, and a body heater (not shown) for maintaining the resin around the spear 1 at an appropriate temperature (350°C). They are installed in the structure, and each is controlled by a separate Spear System Controller.

The runner part IB of the spear 1 is located between the spear 1 and its casing 2, inside the manifold 5, and at the spool bush 21.
and the locate ring 22.

On the balance heater 3 side, the stationary mold 10 is attached. In this stationary mold 10, a concave portion 11 forming a housing portion 12 for mounting an armature coil formed by superimposing a large number of single coils into an annular shape using a molding jig and connecting to a commutator is provided. It is provided in conjunction with. Further, the stationary mold 10 is separately formed with a cartridge heater mounting hole 13 for mounting the cartridge heater 14 and a coolant hole 15 for passing the coolant.

A movable mold 16 is assembled to the fixed mold 10. Similar to the stationary mold 10, the movable mold 16 has a housing section 12 in which an armature coil formed by superimposing a large number of single coils into an annular shape using a molding jig and connecting them to a commutator is installed. A recess 17 is formed.

Further, in the movable mold 16, similarly to the fixed mold 10, a cartridge heater mounting hole 18 for mounting the cartridge heater 19 and a cooling liquid hole 21 for passing the cooling liquid are formed separately. has been done.

Storage part 1 formed by fixed side mold 10 and movable side mold 16
A resin channel layer 12A is provided on the outer circumferential side of No. 2.

The fixed mold 10 and the movable mold 16 are designed to be opened by a known method.

Next, this embodiment will be explained using the apparatus configured as described above.

In this apparatus, as shown in FIG. 5, the resin that has been ff1i by the runner part IB, which is always in a molten state, is cooled and solidified together with the resin in the cavity in the gate land part IA. After taking out the product and before starting the next injection, the chip heater 3 is energized to generate heat to melt and inject the resin in the land portion IA.

This repeating process is synchronized with the cycle of the molding machine, allowing for fully automatic molding.

Therefore, first, using a forming jig, a large number of single coils are superimposed and formed into an annular shape in the housing part 12 formed by the stationary side mold 10 and the movable side mold 16 according to a conventional method, and then connected to a commutator. Attach an amateur coil consisting of:

On the other hand, the resin warmer in the manifold 5 is kept warm and controlled by the cartridge heater 7 divided into two systems (350° C.).

The resin that has passed through the manifold 5 passes around the spear 1 and its casing 2, and stagnates at -. The resin in this part is kept warm by the heater built into the spear 1.
An insulating layer is formed toward the gate land portion IA. The gate land portion IA is solidified by cooling the molds 10 and 16 except during injection, and immediately before injection, the chip heater 3 is energized to generate heat and melt, and is injected into the storage portion 12, and a resin layer is placed on the armature. to be formed. At this time, the storage portion 12 has a gate formed by the spear 1, that is, a land portion I.
Since the resin flow path FJI 2A is provided in the area outside A, the resin injected into the storage section 12 flows along the armature and is filled regardless of variations in the outer diameter of the armature. . Further, the heat generation timing and heat generation time at this time are automatically repeated for each shot, and the output is adjusted individually for each gate.

The fixed side and movable side molds 10.16 are 130 to 150°
To maintain the temperature at C but quickly raise it to a certain temperature,
The cartridge heater 14.19 inserted into the cartridge heater hole 13.18 is energized to raise the temperature.

Furthermore, when continuous molding is performed, resin heated to 350° C. is injected, so the temperatures of the fixed and movable molds 10.16 gradually rise. If this is cooled in a conventional manner, it will take a long time and the molding cycle will be lengthened.

Therefore, in order to cool the mold 10.16, the cooling liquid hole 15
．． Cooling liquid (oil at 100-150°C) is circulated through 20, and the mold temperature is controlled at 130-50°C.

By automatically using a spear temperature controller (not shown), the crystallinity of the mold can be controlled at a constant temperature within the range of 130 to 150 degrees Celsius, making it possible to produce armature molded products with constant quality. can do. or,
Since the spear 1 was placed at each gate position through the manifold 5, the spear 1. A manifold 5, a controller for setting and controlling the output and temperature, and a relay box (not shown) can be provided.

When carrying out the present invention, if a three-point gate system using three spears 1 is used as in the above embodiment, the resin mold layer of the armature for a 1' Hibira type motor can be uniformly molded.

This will be explained based on the inventor's experiments.

In the case of a three-point gate, there are three welds 41 between each gate 40, as shown by the dotted line in Figure 6, but if you gradually increase the amount of material from a small It is completely filled with an even flow distance as shown.

As is clear from this experiment, the gate balance is excellent. Since the weld 41 is completely sealed, there are no defects. There is no cranking, warping, or deformation in the molded product.

When a one-point gate is used, the flow distance from the gate 40 to the weld 41 becomes longer as shown in FIG. 8, so a difference occurs in the flow time of the material. Therefore, the weld 41 is not completely sealed, causing cranking or weakening of the weld 41. Since it shows a flow trajectory like an arrow, it is difficult to fill the left and right sides of the weld due to the orientation of the glass fibers, and it is difficult to form a perfect circle as shown in FIG. Moreover, the weld shaft 42 is deformed as shown in FIG.

Furthermore, if a two-point gate is used, as shown in FIG. 11, the flow distance becomes longer, although not as much as a one-point gate, so that the weld 41 is not completely sealed, resulting in cracks and reduced strength. Since it shows a flow trajectory like an arrow, it deforms on the left and right sides of the weld 41 depending on the orientation of the glass fibers in the same way as a one-point gate. Also, it is difficult to make a perfect circle.

Therefore, in order to eliminate deformation and warpage of the armature, as well as to enable molding that eliminates surface runout and overall shape distortion during rotation of the armature, a three-point gate is required.

In addition, in the present invention, as the thermoplastic resin, ordinary P
Superfluid PPS is preferable to PS.

This superfluid pps is made by filling glass fiber and inorganic substances such as silica in order to balance mechanical strength and fluidity. Its physical properties are shown in Table 1.

Table 1 In Table 1, material A refers to high strength and ultra-high fluidity pps.
<Toshi Co., Ltd.'s product name: NR-4), material B is ultra-high fluidity PPS (Lightre Co., Ltd.'s product name: R-9-
02) and material C represent epoxy resin CEL-874B.

As is clear from Table 1, high strength and ultra-high fluidity PPS
has more than twice the mechanical strength (bending and impact strength) as ultra-high fluidity PPS. Note that the fluidity is the same.

Next, using high-strength and ultra-high fluidity PP5 (trade name: NR-4 of Toshi Co., Ltd.), the temperature of the manifold was 350°C.
℃, nozzle temperature 350℃, cylinder temperature 350℃13
50°C, 34,0°C, mold temperature 150°C (fixed side 12
0℃, oil circulation at movable side 150℃), injection pressure 200
kg/cII! , molding time (injection/cooling) 12 seconds/40
When molded under conditions of 60 seconds and a molding cycle of 60 seconds,
The flatness of the obtained product is 0.005 mm or less, the resistance change rate is 3% or less, and the flatness after heat resistance at 200°C is 0.3 mm.
It was below.

〔Effect of the invention〕

As described above, according to the present invention, a large number of single coils are superimposed and annularly formed using a molding jig, and an armature coil formed by connecting a commitake is formed by forming a resin flow channel layer on the outer periphery of a mold cavity. Insert it into the storage area of the runner-less mold, and put it in the storage area of the runner-less mold with high strength and ultra-high flow! Since thermoplastic resin with fiJj properties is injected under ultra-low pressure and a resin mold layer is molded onto the armature coil, there is no risk of filling defects, and there is no coil deformation or warping due to injection pressure. Surface runout and overall distortion during armature rotation are extremely small and superior compared to the cold runner type. There is no resin loss at all on the sprue and runners. Since it can be cut from the gate and taken out automatically, there is no need to cut or finish the gate.
It can save labor.

Therefore, resource and labor savings can be achieved as a whole, so there are advantages such as being able to provide a low-cost armature molded product.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a partially cutaway front view of an apparatus for manufacturing an armature for a flat type motor according to the present invention, FIG. Figure 3 is a plan view of the armature for a flat type motor molded according to this example, Figure 4 is its cross-sectional view, Figure 5 is a diagram showing the temperature characteristics of the tip heater of the spear used in the present invention, and Figure 6. 11 to 11 are explanatory diagrams showing a comparison between the three-point gate and other gates in the present invention. DESCRIPTION OF SYMBOLS 1... Spear, IA... Land part, IB... Part of runner, 2... Spear casing, 3... Chip heater, 5... Manifold, 10... Fixed side mold,
12... Storage section, 12A... Resin channel layer, 16...
・Movable side mold, 30...Amateur coil, 32...
·Gate. Figure 2 Figure 4 Figure 5 Time (sec)

Claims (6)

[Claims] (1) A runnerless mold in which a large number of single coils are superimposed into an annular shape using a molding jig, and an armature coil formed by connecting a commutator is provided with a resin channel layer on the outer periphery of the mold cavity. A thermoplastic resin with high strength and ultra-high fluidity is injected into the storage part of the runnerless mold under ultra-low pressure to form a resin mold layer on the armature coil. A method for manufacturing an armature for a flat motor. (2) A method for manufacturing an armature for a flat type motor according to claim 1, characterized in that a thermoplastic resin having high strength and ultra-high fluidity is injected using spears arranged at three locations. . (3) The spear is a flat type according to claim 2, wherein each spear body is arranged through a manifold, and each spear body is arranged so that the temperature can be individually controlled by a temperature controller. A method of manufacturing an armature for a motor. (4) A patent characterized in that the mold is rapidly raised to a predetermined temperature by a cartridge heater before the start of molding, and the mold is maintained at a predetermined temperature by passing a cooling liquid into the mold during the molding operation. A method of manufacturing an armature for a flat type motor according to claim 1. (5) The armature for a flat type motor according to claim 1, characterized in that a resin channel layer is arranged on the outer periphery of the armature coil storage part of the runnerless mold and in the cavity on the opposite side of the gate. manufacturing method. (6) The method for manufacturing an armature for a flat motor according to claim 1, wherein the thermoplastic resin is polyphenylene sulfide.