JP2008260190A - Method and apparatus for molding stator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for molding a stator which can prevent the occurrence of a void in a molding resin by preventing the air entrainment of the resin and the fouling or the clogging of a nozzle tip by free shots when the stator is molded by using the resin. <P>SOLUTION: In the molding apparatus 20, an upper part cavity C1, a hollow projection 32 with the peripheral surface engaged/contacted with the hollow part inner circumference surface of the stator 10, a resin injection port 33 formed in the bottom surface central part of the hollow projection 32, and a sprue 34 are set in an upper mold 30. A lower part cavity C2 and a recess 41 for forming a gate 46 and a runner 45 between it and the end surface of the hollow projection 32 of the upper mold 30 are set in a lower mold 40. A resin injection part 50 makes the tip of a nozzle 51 intrude into the hollow projection 32 while it is turned downward and brought down to connect it with the resin injection port 33 to inject the resin 25 into a cavity C. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for molding a stator provided in a motor with resin.

  2. Description of the Related Art Conventionally, resin molding has been performed on a stator (particularly, a coil portion) provided in a motor in order to ensure insulation and strength. As a molding technique for such a stator, generally, a mold in which a gate is disposed on an upper part of a stator to be molded is used, and a nozzle for injecting resin into the mold is provided above the mold. A method is known in which a stator is molded with a resin by injecting resin from a gate located at the top of the stator.

  However, the above-described molding technique has a problem that when the resin is injected from the gate located on the upper portion of the stator, the resin easily entrains air and voids are generated in the molding resin. And when a void generate | occur | produces in mold resin, the intensity | strength and insulation of the stator after a mold will fall. Further, since the resin is injected from the gate located at the upper part of the stator, there is a problem that the sprue becomes long and the material yield is poor.

For this reason, as a technique for solving the above problem, for example, a mold having an air bleeding structure has been proposed (Patent Document 1). In this mold, the intermediate shaft holding the stator core on which the coil is wound has a double structure, the fixing screw for fixing to the two intermediate shafts is hollow, and the gas vent hole is formed from the hollow shaft toward the hollow portion. Provided. For this reason, the gas in the mold resin generated when the central portion flows from the gate port passes through the air vent hole and escapes to the hollow portion of the fixing screw. Thereby, the generated gas can be easily released to the outside of the mold, and the generation of voids in the mold resin is prevented. Further, since the resin is not injected from the gate located at the upper part of the stator, the sprue does not become long, so that the material yield is also improved.
Japanese Patent Laid-Open No. 8-196065

  However, the above-described conventional technique has a problem that air is easily involved because a part of the resin injected from the gate into the mold is injected downward from the gate. That is, it was not possible to prevent air from being entrained during resin injection into the mold. Moreover, since the outer peripheral surface of the stator core (laminated electrical steel sheet) is also molded with resin, there is a problem that the heat dissipation performance of the stator is deteriorated.

  Here, in order to prevent entrainment of air when the resin is injected into the mold, it is conceivable to arrange a nozzle below the mold in order to inject the resin into the mold from the lower part of the stator. However, if the nozzle is arranged below the mold in this way, the nozzle tip is soiled or clogged with resin during free shot, and the nozzle tip needs to be cleaned. For this reason, when the nozzle is arranged below the mold, there is a problem that it is very difficult to perform free shot practically.

  Therefore, the present invention has been made to solve the above-described problems, and when molding a stator with a resin, the resin prevents the resin from entraining air so that no void is generated in the mold resin. It is an object of the present invention to provide a stator molding method and apparatus that can prevent the nozzle tip from becoming dirty and clogged by free shot.

  In the stator molding method according to the present invention made to solve the above-mentioned problems, resin is injected from a nozzle into a pair of molds in which cavities for disposing the stator to be molded are formed, and the stator is resinated. In the stator molding method, the pair of molds in a state in which the outer peripheral surface of the hollow convex portion formed on the upper mold of the pair of molds is fitted and brought into contact with the inner peripheral surface of the hollow portion of the stator. The mold is closed, the nozzle is inserted into the hollow convex portion of the upper mold in a downward state, and the tip of the nozzle is formed in the pair of molds and communicates with a gate connected to the lower end side of the cavity. The resin is injected into the cavity from the nozzle through the runner and gate.

  In this stator molding method, the mold is first closed in a state where the outer peripheral surface of the hollow convex portion formed on the upper mold of the mold is fitted and brought into contact with the inner peripheral surface of the hollow portion of the stator. Next, a nozzle for injecting the resin into the cavity of the mold is made to enter the hollow convex portion formed in the upper mold of the mold in a downward state. Next, the tip of the nozzle is connected to the inlet of the runner that communicates with the gate connected to the lower end side of the cavity. And resin is inject | poured in a cavity through a runner and a gate from a nozzle. Thereby, resin is poured into the cavity from below and the stator is molded.

  As described above, in this molding method, since the resin can be injected into the mold cavity where the stator is disposed from below, it is possible to make it difficult to entrain air when the resin is injected into the mold. . Therefore, generation of voids in the mold resin can be prevented. Further, since the nozzle is disposed downward, it is possible to prevent the nozzle tip from becoming dirty or clogged with resin during free shots.

  In the method for molding a stator according to the present invention, it is desirable to inject resin into the cavity from the nozzle while discharging air in the cavity from the upper end side of the cavity. Preferably, resin is injected into the cavity from the nozzle while sucking air in the cavity from the upper end side of the cavity.

  By doing in this way, air is reliably discharged | emitted from the upper part of a cavity, while resin is inject | poured into the cavity of the metal mold | die with which the stator is arrange | positioned from the lower part. Therefore, generation of voids in the mold resin can be reliably prevented.

  In the stator molding method according to the present invention, it is preferable that when the stator is disposed in the cavity, an outer peripheral portion of the core of the stator is in close contact with the inner wall of the cavity. Preferably, when the stator is disposed in the cavity, the outer peripheral portion of the core end surface of the stator (outer periphery than the coil) is also in close contact with the inner wall of the cavity.

  By doing in this way, when resin is inject | poured into a cavity, resin can be prevented from flowing into the core outer peripheral surface of a stator. As a result, only the coil portion of the stator can be molded with resin. In other words, the core outer peripheral surface of the stator is not molded with resin. Thereby, it can prevent that the thermal radiation performance of a stator deteriorates.

  In the stator molding apparatus according to the present invention made to solve the above problems, a pair of molds in which cavities for disposing the stator to be molded are formed, and a nozzle for injecting resin into the cavities are provided. In the stator molding apparatus having the resin injection portion including the upper mold, the upper mold of the pair of molds is fitted with an upper cavity that forms part of the cavity, and an outer peripheral surface is fitted to the inner peripheral surface of the hollow portion of the stator. A hollow convex portion in contact with the resin injection port formed at the center of the bottom surface of the hollow convex portion, and the lower mold of the pair of molds includes a lower cavity that forms part of the cavity, and the upper mold A recess is formed between the end surface of the hollow convex portion of the mold and a runner communicating the gate and the resin injection port while forming a gate on the inner peripheral side of the lower end of the cavity, The resin injection portion is inserted into the hollow convex portion while being lowered with the tip of the nozzle faced downward and connected to the resin injection port, and the resin is injected into the cavity from the nozzle through the runner and gate. It is characterized by being injected into.

  The stator molding apparatus includes a pair of molds in which cavities for disposing the stator are formed, and a resin injection unit including a nozzle for injecting resin into the cavities. In the upper mold of the mold, an upper cavity forming a part of the cavity, a hollow convex portion whose outer peripheral surface is fitted and abutting on the inner peripheral surface of the hollow portion of the stator, and a central portion of the bottom surface of the hollow convex portion are formed. And a resin injection port. Further, the lower mold of the mold is formed with a gate on the inner peripheral side of the lower end of the cavity between the lower cavity forming a part of the cavity and the end surface of the hollow convex portion of the upper mold, and the gate and the resin injection port. And a recess for forming a runner that communicates with each other. Thus, by closing the upper mold and the lower mold, a cavity is formed by the upper cavity and the lower cavity, and a gate and a runner are formed by the end surface of the hollow protrusion of the upper mold and the recess of the lower mold. .

And since the hollow convex part which the outer peripheral surface fits and contacts with the hollow peripheral inner peripheral surface of the stator is formed in the upper mold, the resin injection part is placed in the hollow convex part while being lowered with the tip of the nozzle facing downward. The resin can be injected into the cavity from the nozzle through the runner and the gate by intruding and connecting to the resin injection port.
Here, since the gate is formed on the inner peripheral side of the lower end of the cavity, the resin can be injected into the cavity from below. This makes it difficult to entrain air when the resin is injected into the mold, so that voids can be prevented from occurring in the mold resin. Further, since the nozzle is disposed downward, it is possible to prevent the nozzle tip from becoming dirty or clogged with resin during free shots. Furthermore, since the resin injection port is formed at the center of the bottom surface of the upper hollow convex portion, the sprue can be shortened, so that the material yield is also improved.

  In the stator molding apparatus according to the present invention, it is preferable that the upper mold is provided with an air discharge passage for discharging the air in the cavity from the upper end side of the cavity to the outside of the mold. Preferably, a suction means for sucking the inside of the air discharge passage is further provided.

  This is because the air in the cavity is surely discharged from the upper part of the cavity through the air discharge passage while the resin is injected into the cavity of the mold in which the stator is disposed. As a result, generation of voids in the mold resin can be reliably prevented.

  In the stator molding device according to the present invention, it is desirable that the cavity is formed such that a core outer peripheral portion of the stator is in close contact with the wall surface of the cavity when the stator is disposed. Preferably, the cavity is formed such that when the stator is disposed in the cavity, the outer peripheral portion of the core end surface of the stator (outer periphery than the coil) is also in close contact with the wall surface of the cavity.

  By forming the shape of the cavity in this way, the resin can be prevented from flowing into the outer peripheral surface of the core of the stator when the resin is injected into the cavity. As a result, only the coil portion of the stator can be molded with resin. In other words, the core outer peripheral surface of the stator is not molded with resin. Thereby, it can prevent that the thermal radiation performance of a stator deteriorates.

  According to the method and apparatus for molding a stator according to the present invention, as described above, when the stator is molded with a resin, the resin can be prevented from entraining air so that no void is generated in the mold resin. At the same time, it is possible to prevent the nozzle tip from becoming dirty or clogged due to free shots.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a most preferred embodiment embodying a stator molding method and apparatus according to the present invention will be described in detail with reference to the drawings.
First, a stator molded by the stator molding method and apparatus of the present invention will be described with reference to FIGS. FIG. 1 is a plan view showing a schematic configuration of the stator. FIG. 2 is a cross-sectional view taken along the line ABC shown in FIG.

As shown in FIGS. 1 and 2, the stator 10 includes a stator core 13 made of a laminated steel plate having 12 teeth 13 </ b> A on the inner periphery, and a plurality of coils 11 and 12 attached to the stator core 13. . Here, the coil 11 is a parallel winding coil in which the outer side of the coil is parallel in a state where the winding 14 is wound around the insulator 15. The coil 12 is an inclined winding coil in which the outer side of the coil forms an inclined surface in a state where the winding 14 is wound around the insulator 15. Parallel winding coils 11 and inclined winding coils 12 are alternately arranged on the teeth 13 </ b> A of the stator core 13. Thereby, the space factor of the coil | winding 14 in a slot is made high. The inner peripheral surface of the tooth 13A is processed with high accuracy, and forms a highly accurate cylindrical space. Three positioning holes 19 are formed in the stator core 13.
The parallel winding coil 11 and the inclined winding coil 12 are connected by a bus bar 16 so as to form a three-phase coil of U, V, and W. Each end of the U, V and W phases of the bus bar 16 is connected to three terminals 18U, 18V and 18W.

Next, a molding apparatus for molding the stator will be described with reference to FIGS. FIG. 3 is a cross-sectional view showing the main configuration of the molding apparatus in a state where the mold is opened. FIG. 4 is a cross-sectional view showing the main configuration of the molding apparatus in a state where the mold is closed. FIG. 5 is a perspective view showing shapes of the runner and the gate.
As shown in FIGS. 3 and 4, the molding apparatus 10 includes an upper mold 30 and a lower mold 40 that are closed and opened with each other in order to mold (resin seal) the stator 10 as a work, and a resin. A resin injection part 50 for injecting into the mold is provided.

  The upper mold 30 is provided so as to move up and down by a predetermined actuator (not shown). In addition, as an actuator, a hydraulic cylinder, an air cylinder, etc. are used, for example. The upper mold 30 is formed with an upper cavity C1 that constitutes the cavity C. The upper cavity C1 is formed with a stator core holding portion 31 that holds the coils 11 and 12 of the stator core 13, the insulator 15, and the upper surface on the outer peripheral side of the bus bar 16. The stator core holding portion 31 comes into contact with the outer peripheral upper surface of the stator core 13 over the entire circumference when the mold is closed in a state where the stator 10 is disposed in the mold.

  In addition, a spare cavity 35 is formed so as to be connected to the outer peripheral side of the upper end of the upper cavity C1. Thus, when the resin is injected into the cavity C, the air in the cavity C is collected and a part of the resin flows into the spare cavity 35. An air discharge passage 36 communicating with the outside of the upper mold 30 is formed in the preliminary cavity 35. As a result, the air collected in the preliminary cavity 35 is discharged to the outside through the air discharge passage 36. In addition, it is preferable to provide at least one preliminary cavity 35 in the vicinity of the resin final filling portion of the cavity C. By doing so, the air in the cavity C can be reliably collected in the spare cavity 35, so that the air can be prevented from being caught in the resin. In addition, the resin final filling location of the cavity C can be obtained by experiments such as simulating the flow of the resin.

  A hollow convex portion 32 having a downward convex shape is formed at the center of the upper mold 30. When the mold is closed in a state where the stator 10 is disposed in the mold, the outer peripheral surface of the hollow convex portion 32 is fitted and brought into contact with the inner peripheral surface of the teeth 13 </ b> A of the stator core 13. A resin injection port 33 for injecting resin into the mold is opened at the center of the bottom surface of the hollow protrusion 32. A sprue 34 is provided on the bottom surface of the hollow convex portion 32 and communicates with the resin injection port 33 and penetrates the bottom surface of the hollow convex portion 32 and has a substantially conical shape. Since the sprue 34 is formed so as to penetrate the bottom surface of the hollow convex portion 32, the length of the sprue 34 can be extremely shortened, and the resin (mold material) yield can be improved.

On the other hand, the lower mold 40 is formed with a lower cavity C2 constituting the cavity C. The outer diameter of the lower cavity C2 is set so that the end surface of the lower mold 40 can be held with the lower surfaces on the outer peripheral side of the coils 11 and 12, the insulator 15, and the bus bar 16 of the stator core 13 interposed therebetween. Thereby, when the mold is closed in a state where the stator 10 is disposed in the mold, the end surface inner peripheral side portion 40 a of the lower mold 40 abuts over the entire outer peripheral lower surface of the stator core 13. .
Three positioning pins 42 for positioning the positioning holes 19 of the stator core 13 are provided on the end surface of the lower mold 40.
Further, a circular recess 41 is formed inside the lower cavity C2 below the lower cavity C2. The concave portion 41 is connected to the lower cavity C2 at the outer peripheral end, and the connecting portion 41a has a tapered shape.

  Here, the recess 41 includes a runner 45 communicating with the sprue 34 between the upper mold 30 and the lower mold 40 when the upper mold 30 and the lower mold 40 are closed, and the runner 45 and the cavity. In order to communicate with C, a gate 46 connected to the inner peripheral side of the lower end of the cavity C is formed. As a result, the runner 45 and the gate 46 are formed in a disk shape as shown in FIG.

  By closing the upper mold 30 and the lower mold 40 as described above, a cavity C is formed by the upper cavity C1 and the lower cavity C2, as shown in FIG. A runner 45 and a gate 46 are formed by the recess 41. Thus, the resin injected from the resin injection port 33 flows into the cavity C through the sprue 34, the runner 45, and the gate 46.

  And, in the resin injection part 50 for injecting resin into the cavity C constituted by the upper mold 30 and the lower mold 40 as described above, as shown in FIG. 3, a cylinder 52 provided with a screw inside, An injection nozzle 51 provided at the tip of the cylinder 52 and a screw extrusion cylinder 53 for moving the screw in the cylinder 52 up and down are provided. The resin injection unit 50 is provided with a predetermined actuator (not shown) and can move up and down.

  Subsequently, a procedure of molding the stator 10 by the above-described molding apparatus 20 will be described with reference to FIGS. FIG. 6 is a view showing a state in which the stator 10 is set on the lower mold 40. FIG. 7 is a view showing a state in which the upper mold 30 is closed with respect to the lower mold 40. FIG. 8 is a diagram illustrating a state in which resin has started to be injected into the cavity C. FIG. FIG. 9 is a diagram illustrating a state where the filling of the resin into the cavity C is completed. FIG. 10 is a perspective view showing the stator 10a after molding.

  First, as shown in FIG. 6, the upper mold 30 is moved upward by an actuator (not shown) and separated from the lower mold 40. That is, the upper mold 30 and the lower mold 40 are opened. In this state, the stator 10 is disposed in the lower cavity C1 of the lower mold 40 by the handling device or the operator. At this time, positioning is performed by fitting the positioning hole 19 to the positioning pin 37.

Next, as shown in FIG. 7, the upper mold 30 is lowered by an actuator (not shown). As a result, the upper mold 30 comes into contact with the lower mold 40 and is closed. At this time, the outer periphery of the hollow convex portion 32 of the upper mold 30 and the inner periphery of the teeth 13A of the stator core 13 are fitted and contacted. Then, the upper mold 30 is further lowered so that a pressing force of several tens of tons is applied. That is, the mold is clamped. By applying a load of several tens of tons in this manner, the gap between the steel plates of the stator core 13 made of laminated steel plates is eliminated, and the outer peripheral upper surface of the stator core 13 and the stator core holding portion 31 of the upper mold 30 are brought into close contact with each other. The outer peripheral lower surface of the lower mold 40 and the end surface inner peripheral side portion 40a of the lower mold 40 can be adhered to each other.
In this state, the resin injection part 50 is moved downward by an actuator (not shown). Thus, the injection nozzle 51 enters the hollow portion of the hollow convex portion 32 of the upper mold 30 in a downward state, and the tip thereof is connected to the resin injection port 33.

  As shown in FIG. 8, when the injection nozzle 51 is connected to the resin injection port 33, the screw extrusion cylinder 53 is driven to start injection of the resin (mold material) 25 from the resin injection port 33. The resin 25 enters the cavity C from the lower end side of the cavity C from the resin injection port 33 through the sprue 34, through the disk-shaped runner 45, and through the gate 46 from all positions of 360 degrees. Here, the width of the portion of the gate 46 that enters the cavity C from the runner 45 becomes narrow, and the stator and the runner can be easily separated after the molding. When the resin 25 is injected into the cavity C, a suction device (not shown) (for example, a vacuum generator) connected to the air discharge passage 36 communicating with the preliminary cavity 35 disposed above the cavity C is used. Air in the cavity 26C is drawn. This is because there are many complicated spaces in the coil of the stator 10 and the resin enters all the spaces.

As described above, in this embodiment, the resin can be injected from the injection nozzle 51 into the cavity C from below the cavity C with the tip of the injection nozzle 51 facing downward. For this reason, it is difficult to entrain air during resin injection. In addition, since the air in the cavity C is drawn from above the cavity C by using a suction device (not shown) at the time of resin injection, the resin is injected from below the cavity C and the air from above the cavity C. Is sucked (discharged). Thereby, since the resin 25 injected into the cavity C can be reliably prevented from entraining air, the occurrence of voids in the mold resin can be reliably prevented. Thereby, it can avoid that the intensity | strength of a stator after molding, heat transfer performance, etc. fall remarkably.
Furthermore, since the tip of the injection nozzle 51 is disposed downward, it is possible to prevent the nozzle tip from becoming dirty or clogged with resin during a free shot as will be described later.

  Then, the resin 25 is gradually filled into the cavity C from below. At this time, the upper mold 30 and the lower mold 40 are strongly pressed across the stator core 13. More specifically, the stator core holding portion 31 of the upper die 30 presses the outer peripheral upper surface of the stator core 13, and the end surface inner peripheral side portion 40 a of the lower die 40 presses the outer peripheral lower surface of the stator core 13. For this reason, there is no gap between the steel plates of the stator core 13, the outer peripheral upper surface of the stator core 13 and the stator core holding portion 31 of the upper die 30 are in close contact, and the outer peripheral lower surface of the stator core 13 and the end surface inner peripheral side portion 40 a of the lower die 40. Is in close contact. Thereby, resin does not leak from the outer peripheral part of the stator core 13. Further, since the outer peripheral surface of the hollow convex portion 32 of the upper mold 30 is in contact with the inner peripheral surface of the teeth 13A of the stator core 13, the resin does not enter the gap. Therefore, the inner peripheral surface and the outer peripheral surface of the stator core 13 can be reliably avoided from being molded with resin, so that the heat dissipation performance of the stator can be prevented from deteriorating.

  Thereafter, the filling of the resin 25 into the cavity C is continued. As shown in FIG. 9, when the resin 25 is completely filled into the cavity C, the screw extrusion cylinder 53 is stopped and the resin 25 from the injection nozzle 51 is stopped. The injection of is finished. At this time, the preliminary cavity 35 is also filled with a little resin 25. Since this preliminary cavity 35 is provided in the resin final filling portion of the cavity C, it can be said that the resin 25 is filled in the entire area of the cavity C by filling the preliminary cavity 35 with a little resin 25. That is, an appropriate amount of the resin 25 can be reliably filled in the cavity C.

  Then, after filling the cavity C with the resin, the resin injection part 50 is moved upward by an actuator (not shown). Next, when the resin 25 filled in the cavity C is cured, the upper mold 30 is moved upward by an actuator (not shown) to open the mold. Then, the molded stator 10 is carried out from the molding apparatus 20. Thereafter, excess resin filled in the preliminary cavity 35 is removed. Thus, as shown in FIG. 10, the molded portion 17 is not formed on the outer peripheral surface and the inner peripheral surface of the stator core 13, but only on the coils 11, 12, the insulator 15, and the bus bar 16. The molded stator 10a is completed.

  When the free shot is executed, a resin receiver (not shown) is disposed below the injection nozzle 51 and the screw extrusion cylinder 53 is driven. As a result, the resin is injected from the injection nozzle 51 onto the resin receiver and a free shot is performed. At this time, since the tip of the injection nozzle 51 is arranged downward, it is reliably prevented that the nozzle tip is stained or clogged with resin.

  As described above, according to the stator molding apparatus 20 according to the present embodiment, the upper mold 30 includes the upper cavity C1 that forms part of the cavity C, and the outer peripheral surface is the inner periphery of the hollow portion of the stator 10. A hollow convex portion 32 fitted and abutted on the surface, and a resin injection port 33 and a sprue 34 formed at the center of the bottom surface of the hollow convex portion 32 are provided. In the lower die 40, a gate 46 is formed on the inner peripheral side of the lower end of the cavity C between the lower cavity C <b> 2 forming a part of the cavity C and the end surface of the hollow convex portion 32 of the upper die 30. And a recess 41 for forming a runner 45 that communicates with the sprue 34. Thereby, by closing the upper mold 30 and the lower mold 40, the upper cavity C1 and the lower cavity C2 form a cavity C, and the end surface of the hollow convex portion 32 of the upper mold 30 and the concave portion 41 of the lower mold 40 are formed. As a result, the gate 45 and the runner 46 are formed.

Thus, since the outer convex surface is formed in the upper mold 30 so that the outer peripheral surface is fitted and brought into contact with the inner peripheral surface of the teeth 13A of the stator core 13, the resin injection unit 50 has the tip of the nozzle 51 facing downward. The resin 25 is introduced into the cavity C through the sprue 34, runner 45, and gate 46 from the nozzle 51 through the sprue 34, the runner 45, and the gate 46. Can be injected from. Therefore, since the resin 25 can make it difficult to entrain air when the resin is injected into the cavity C, voids can be prevented from occurring in the mold resin.
In addition, since the nozzle 51 is disposed downward, it is possible to prevent the nozzle tip from becoming dirty or clogged with resin during free shots.

  It should be noted that the above-described embodiment is merely an example and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, the runner 46 is formed in a disk shape, but the shape of the runner is not limited to this. For example, as shown in FIG. Even if the runner is formed, the above-described effects can be obtained.

  In the above-described embodiment, the upper mold 30 is moved and the lower mold 40 is fixed. On the contrary, the upper mold 30 may be fixed and the lower mold 40 may be moved. Both the upper mold 30 and the lower mold 40 may be movable. Furthermore, in the above-described embodiment, the case where the present invention is applied to a three-phase stator is illustrated, but the present invention can be applied to a stator other than a three-phase stator.

It is a top view which shows schematic structure of a stator. It is sectional drawing in ABC shown in FIG. It is sectional drawing which shows the main structures of the molding apparatus in the state where the mold was opened. It is sectional drawing which shows the main structures of the molding apparatus in the state where the mold was closed. It is a perspective view which shows the shape of a runner and a gate. It is a figure which shows the state which set the stator to the lower mold | type. It is a figure showing the state where the upper model was closed to the lower model. It is a figure which shows the state which resin has begun inject | poured into the cavity. It is a figure which shows the state which complete | finished filling of the resin in a cavity. It is a perspective view which shows a molding stator. It is a figure which shows the modification of a runner.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Stator 10a Molding stator 11 Parallel winding coil 12 Inclined winding coil 13 Stator core 13A Teeth 14 Winding 20 Molding device 25 Resin 30 Upper mold 31 Stator core holding part 32 Hollow convex part 33 Resin injection port 34 Sprue 35 Preliminary cavity 36 Air discharge Passage 40 Lower mold 40a End surface inner peripheral side 41 Recess 41a Connection part 42 Positioning pin 45 Runner 46 Gate 50 Resin injection part 51 Injection nozzle 52 Cylinder 53 Screw extrusion cylinder C Cavity C1 Upper cavity C2 Lower cavity

Claims (6)

In a stator molding method in which resin is injected from a nozzle into a pair of molds in which cavities for disposing a stator to be molded are formed, and the stator is molded with resin.
The pair of molds are closed in a state where the outer peripheral surface of the hollow convex portion formed on the upper mold of the pair of molds is fitted and brought into contact with the inner peripheral surface of the hollow portion of the stator,
The nozzle is inserted downward into the hollow convex portion of the upper mold, and the tip of the nozzle is formed in the pair of molds and is connected to a gate connected to the lower end side of the cavity. connection,
A stator molding method, wherein resin is injected into the cavity from the nozzle through the runner and gate. The stator molding method according to claim 1,
A stator molding method, wherein resin is injected into the cavity from the nozzle while discharging air from the upper end side of the cavity. In the stator molding method according to claim 1 or 2,
A stator molding method, wherein when the stator is disposed in the cavity, a core outer peripheral portion of the stator is in close contact with a wall surface of the cavity. In a stator molding apparatus having a pair of molds in which a cavity for placing a stator to be molded is formed, and a resin injection part including a nozzle for injecting resin into the cavity,
The upper mold of the pair of molds includes an upper cavity that forms a part of the cavity, a hollow convex portion whose outer peripheral surface is fitted and abutted with the inner peripheral surface of the hollow portion of the stator, and the center of the bottom surface of the hollow convex portion A resin inlet formed in the part,
The lower mold of the pair of molds forms a gate on the inner peripheral side of the lower end of the cavity between a lower cavity forming a part of the cavity and an end surface of the hollow convex portion of the upper mold, and A recess for forming a runner communicating the gate and the resin injection port;
The resin injection part is inserted into the hollow convex part while being lowered in a state where the tip of the nozzle is faced downward, and is connected to the resin injection port. The resin is injected from the nozzle through the runner and gate into the cavity. A stator molding device characterized by being injected into the inside. In the stator molding device according to claim 4,
The stator mold apparatus, wherein the upper mold is provided with an air discharge passage for discharging air in the cavity from the upper end side of the cavity to the outside of the mold. In the stator molding device according to claim 4 or 5,
The stator molding apparatus, wherein the cavity is formed so that a core outer peripheral portion of the stator is in close contact with a wall surface of the cavity when the stator is disposed.

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