JPH0349735B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of 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 using a thermoplastic resin. [Prior Art] Conventionally, this type of flat type motor armature is known, for example, as disclosed in Japanese Patent Application Laid-Open No. 57-52352. The manufacturing method for this flat type motor armature involves filling a resin flow path (runner) that connects the nozzle of the molding machine with the cavity of the mold, and sealing the armature with the resin filling the cavity. There is a cold runner system in which the molded armature is cooled and solidified, the mold is opened, and the mold is discharged together with the armature. [Problems to be Solved by the Invention] 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, it has been proposed to use polyphenylene sulfide resin (hereinafter referred to as PPS) as a thermoplastic resin, which has higher strength and fluidity than general-purpose resins, for this type of armature. , this PPS
Although it has high fluidity, in order to form an armature by filling resin into an armature coil, which is made up of a plurality of single coils filled with conductive wire and arranged radially, as in the publication, it is necessary to charge the resin. Because the resin needs to flow between the stacked conductive wires, considerable fluidity is required, so fluidity is not sufficient for forming the armature, and the rate of failure due to filling is high. In contrast, ultra-high fluidity PPS with improved fluidity
Although the defect rate due to filling is low, the mechanical strength of PPS is insufficient and cracks occur in some parts when the shaft is press-fitted, resulting in rejected products. [Object of the Invention] The present invention was made in order to solve the conventional problems, and the purpose is to provide a method for manufacturing an armature for a flat type motor that does not cause filling defects with thermoplastic resin. It's about doing. [Means for Solving the Problems] The method for manufacturing an armature for a flat type motor according to the present invention is to form an armature in which a large number of single coils are superimposed into an annular shape using a forming jig and connected to a commutator. The coil is inserted into the storage part of a runnerless mold that has a resin flow path layer on the outer periphery of the mold cavity, and the ultra-high fluidity polyphenylene sulfide resin is inserted into the storage part of the runnerless mold. We inject ultra-high fluidity, high-strength polyphenylene sulfide resin that has mechanical strength more than twice as high as that of It is formed into a coil. [Function of the invention] In the present invention, a resin channel layer is provided on the outer periphery of the mold cavity, and a high mechanical strength that is more than twice that of ultra-high fluidity polyphenylene sulfide resin is provided. Since we use ultra-high fluidity, high-strength polyphenylene sulfide resin that has a , a uniform resin mold layer can be obtained. [Embodiments of the Invention] Hereinafter, embodiments of the present invention will be described based on the drawings. Fig. 1 is a partially cutaway front view of a device for manufacturing an armature for a flat type motor according to the present invention, Fig. 2 is a cross-sectional view showing the main parts thereof, and Fig. 3 is a molded product according to this embodiment. FIG. 4 is a plan view of the flat type motor armature, and a sectional view thereof. The apparatus includes a manifold 5, a spear 1, etc., and is composed of a resin supply section A for supplying resin, a fixed mold 10 forming a cavity C, and a movable mold 16. The cavity C includes a boss recess 11 and a resin flow path layer 12A, which will be described later, carved in the fixed mold 10, and a commutator accommodating part 12, which will be described later, and an amateur coil accommodating part 17, which are carved in the movable mold 16. is formed from. In the figure, 1 is three spears, which are fixed to a manifold 5. Casing 2 of each spear 1
A runner bush 23 is provided at the runner bush 23. A tip heater 3 is provided at the tip of each spear 1. A lead wire 4 is taken out from the other end of the spear 1 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 the boss portions 3 of a resin-molded armature 30, which is a product shown in FIG.
1 so that gates 32 are formed at equal intervals. In addition, the spear 1 is equipped with a chip heater 3 for melting the solidified resin in the land portion 1A, and a body heater (not shown) for maintaining the resin around the spear 1 at an appropriate temperature (310 to 350 degrees Celsius). They are installed in the structure, and each is controlled by a separate Spear System Controller. The runner portion 1B of the spear 1 is formed in a path connecting the spear 1 and its casing 2, inside the manifold 5, the spool bush 21, and the locate ring 22. A stationary mold 10 is attached to the chip heater 3 side. This stationary side mold 10 is provided with a boss recess 11 that forms a boss 3 of the armature, which will be described in detail later, and is connected to a land portion 1A having a chip heater 3. A resin channel layer 12A forming a section is carved.
Further, the stationary side mold 10 is separately formed with a cartridge heater mounting hole 13 for mounting a cartridge heater 14 and a cooling hole 15 for passing a cooling liquid. A movable mold 16 is assembled to the fixed mold 10. This movable side mold 16 is formed with an amateur coil storage part 17 in which an amateur coil is installed, which is formed by superimposing a large number of single coils into an annular shape using a forming jig and connecting them to a commutator. A commutator accommodating part 12 for accommodating a commutator protruding in the shape of a disc from the center of the coil is cut down into the center of the amateur coil accommodating part 17. or,
The movable side mold 16 has, like the fixed side mold 10,
A cartridge heater mounting hole 18 for mounting a cartridge heater 19 and a coolant hole 20 for passing a coolant are formed separately. The stationary mold 10 and the movable mold 16 are designed to be able 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 guided by the runner part 1B, which is always in a molten state, is cooled and solidified together with the resin in the cavity in the gate land part 1A. After taking out the product and before starting the next injection, the chip heater 3 is energized to generate heat to melt the solidified resin in the gate land portion 1A and enable injection. This repeating process is synchronized with the cycle of the molding machine, allowing for fully automatic molding. Therefore, first, in the cavity C formed by the stationary side mold 10 and the movable side mold 16 according to the conventional method,
A large number of single coils are superimposed into an annular shape using a forming jig and connected to a commutator to form an amateur coil. On the other hand, the resin in the manifold 5 is kept warm and controlled (310 to 350°C) by cartridge heaters 7 divided into two systems. The resin that has passed through the manifold 5 passes around the spear 1 and its casing 2 and temporarily stagnates. This part of the resin is Spear 1
The temperature is maintained by a built-in heater, and the gate land portion 1A is solidified by cooling the stationary mold 10 and the movable mold 16 except during injection, forming a retaining layer for the molten resin. are doing. Immediately before injection, the chip heater 3 is energized to generate heat and melt the holding layer, and the holding layer is injected into the cavity C and molded into an armature coil into a resin layer. At this time, the resin injected into the cavity C from the gate formed by the spear 1, that is, the gate land portion 1A, first fills the boss recess 11 and the commutator storage portion 12, but the resin is not applied to the upper surface of the armature coil. The resin flowing along immediately flows into the resin flow path layer 12A on the outer periphery of the cavity C, and further,
Since the resin flows through the resin channel layer 12A and immediately spreads all over the circumference, it is filled regardless of variations in the outer diameter of the armature coil. 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 mold 10 and the movable side mold 16 are 130~
The temperature is maintained at 150° C., but in order to rapidly raise the temperature to a predetermined temperature, the cartridge heaters 14 and 19 inserted into the cartridge heater holes 13 and 18 are energized to heat and raise the temperature. Further, when continuous molding is performed, the heated resin is injected at a temperature of 310 to 350°C, so the temperatures of the stationary mold 10 and the movable mold 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 stationary mold 10 and the movable mold 16, a cooling liquid (oil at 100 to 150°C) is circulated through the cooling liquid holes 15 and 20, and the mold temperature is raised to 130 to 150°C.
Control at 150℃. In addition, by automatically controlling the spear temperature controller (not shown), the mold temperature is always kept at 130~130°C.
The temperature can be controlled at a constant temperature within the range of 150°C, and armature molded products with constant quality can be manufactured. In addition, since the spear 1 is placed at each gate position via the manifold 5, the spear 1 and the manifold 5 to be assembled into the stationary mold 10 are
A controller and a relay box (not shown) can be provided to set and control the output and temperature. 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 flat 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 (joints) 41 between each gate 40, as shown by the dotted line in FIG. 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 are no cracks, warpage, or deformation in the molded product. If 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 that a difference occurs in the flow time of the material. Therefore, the weld 41 is not completely sealed, causing cracks and weakening the strength. Since it shows a flow trajectory like an arrow, the orientation of the glass fibers makes it difficult to fill the left and right sides of the weld, making it 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 as shown by an arrow, it deforms on the left and right sides of the weld 41 due to 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 addition to eliminating deformation and warping of the armature,
In order to enable molding without surface runout, umbrella distortion, etc. during armature rotation, a three-point gate is required. Next, the ultra-high-flow, high-strength material has a mechanical strength that is more than twice that of conventional ultra-high-flow PPS.
Explain PPS. This ultra high fluidity high strength
PPS is made by filling glass fiber and inorganic materials such as silica to balance mechanical strength and fluidity. Its physical properties are shown in Table 1.

〔Effect of the invention〕

As described above, according to the present invention, a large number of single coils are superimposed and formed into an annular shape using a forming jig, and a fluidized resin layer is provided on the outer periphery of the mold cavity to form an armature coil that is connected to a commutator. The resin is inserted into the storage part of a runnerless mold, and has a high mechanical strength that is more than twice that of ultra-high fluidity polyphenylene sulfide resin. Ultra-high fluidity, high-strength polyphenylene sulfide resin is injected, and the mold layer of this ultra-high fluidity, high-strength polyphenylene sulfide resin is formed into an armature coil, so there is no risk of filling defects. , there is no coil deformation or warping due to injection pressure, and surface runout and umbrella distortion when the armature rotates are extremely small compared to the cold runner type, making it superior. There is no resin loss at all in the sprue and runner parts. Since it can be cut from the gate and automatically taken out, there is no need to cut or finish the gate, resulting in labor savings. Therefore,
Since resource and labor savings are achieved as a whole, there are advantages such as being able to provide a low-cost armature molded product.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway front view of a device 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. FIG. 4 is a plan view of the molded armature for a flat type motor, FIG. 4 is a cross-sectional view thereof, FIG. FIG. 3 is an explanatory diagram showing a comparison between a three-point gate and other gates. 1...Spear, 1A...Gateland Department, 1B
...Runner section, 2...Casing, 3...Chip heater, 5...Manifold, 10...Fixed side mold, 12...Commutator storage section, 12A...
Resin channel layer, 16...Movable mold, 17...Amateur coil storage section, 30...Amateur coil, 32...Gate, A...Resin supply section, C...
Cavity.

Claims (1)

[Claims] 1. An armature coil formed by superimposing and annularly molding a large number of single coils using a molding jig and connected to a commutator, and a runner with a resin channel layer provided on the outer periphery of a mold cavity. It is inserted into the housing of a runner-less mold, and the ultra-high fluidity polyphenylene sulfide resin has a mechanical strength that is more than twice that of ultra-high fluidity polyphenylene sulfide resin. A method for producing an armature for a flat type motor, which comprises injecting a highly fluid, high-strength polyphenylene sulfide resin, and forming a molded layer of the ultra-high fluidity, high-strength polyphenylene sulfide resin into an armature coil. . 2. High-strength and ultra-high fluidity high-strength polyphenylene sulfide resin with mechanical strength more than twice that of ultra-high fluidity polyphenylene sulfide resin is injected using spears placed at three locations. A method of manufacturing an armature for a flat type motor according to claim 1, characterized in that: 3. The electric machine for a flat type motor according to claim 1, wherein the spears each have a spear body disposed through a manifold, and are configured such that the temperature can be controlled individually by temperature control. Method of producing children. 4. A patent characterized in that the mold is rapidly raised to a predetermined temperature using 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 motor according to claim 1. 5. Manufacture of an 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. Method.