JP2017007353A - Resin mold device and resin mold method for motor core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin mold device improved in the fillability of a mold resin by acting final resin pressure to a narrow mold space in a magnet insertion hole without strengthening cramp force to a motor core.SOLUTION: In either a stationary die to be mounted with a motor core 1 or a movable die cramping the motor core 1, overflow cavities 28 connected to the opening of each magnet insertion hole 2 of the motor core 1 are formed, respectively, and each overflow cavity 28 is provided with a movable member 26 of pressing back a mold resin 22 made to overflow to each magnet insertion hole 2.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a resin molding apparatus that resin molds, for example, a motor core with a built-in magnet, and a resin molding method of a motor core that uses this to resin mold a motor core.

  2. Description of the Related Art There is known an embedded magnet type motor that includes a magnet inside a rotor and rotates the rotor by an electromagnetic action that acts between a rotating magnetic field generated in the stator and the rotor. The rotor of this embedded magnet type motor has a shaft, a motor core supported by the shaft, and a magnet fixed to the motor core. As the motor core, a laminated core configured by laminating steel plates in the axial direction is used, and a magnet accommodation hole for accommodating a magnet is formed in the laminated core.

The motor core has a hollow hole on the inner side in the radial direction from the magnet housing hole, and a resin mold apparatus for injecting the resin into the gap between the magnet housing hole and the magnet on the steel plate at one end in the axial direction of the motor core. Cull seats that form the bottom surface of the part are formed. When the magnet is fixed to the motor core by resin molding, the kull seat prevents the kull portion from being caught in the through hole, and the resin from leaking from the kull portion to the through hole.
Also, the motor core shaft opening is fitted into the lower mold convex part to close the bottom of the magnet insertion hole, and then the magnet is inserted into the magnet storage hole, the upper mold is closed, and the upper mold pot and upper mold Resin is injected into the gap between the magnet and the magnet housing hole through the cull, and is resin-molded (Patent Document 1).

JP 2009-100654 A

However, the resin molding apparatus by transfer molding shown in Patent Document 1 described above does not have a structure for positioning the magnet inserted into the magnet housing hole of the motor core. For this reason, there exists a possibility that resin molding may be performed in a state where the clearance between the magnet and the inner wall surface of the magnet housing hole varies. As a result, there is a possibility that the motor characteristics may be deteriorated due to disturbance of the magnetic flux balance of the magnetic lines of force generated from the plurality of magnetic flux acting surfaces.
In addition, since the motor core is formed with a cull seat that becomes a cull bottom surface when resin is poured into the gap between the magnet housing hole and the magnet, only the steel plate corresponding to the end of the laminated core is calculated from the core production stage. Processing to provide a seat is required, and the manufacturing cost of the core increases, and the direction of setting to the resin mold is also generated, making it difficult to handle in manufacturing.
Further, since a laminated core in which electromagnetic steel sheets are laminated is used as the motor core, there are individual differences in thickness, and there is a possibility that resin leakage may occur even if the mold is closed.

In particular, since the filling balance of the mold resin cannot be made uniform in the gap between the cores around the magnet, there is a problem in the resin filling property when the resin is molded by biasing the magnet toward one side in the radial direction of the magnet insertion hole. When the mold resin-clamped magnet supplied to the magnet insertion hole is clamped with the mold, the mold mold cannot increase the clamping pressure beyond the thickness of the motor core, so the final resin pressure is applied to the mold resin in the magnet insertion hole. There is a risk that unfilled or voids may occur due to the fact that they do not act.
In addition, since the resin path is changed due to the change of the motor core type, it is necessary to replace the mold.
In addition, since the heat capacity increases when the motor core becomes large, heating takes time, and there is a problem in handling in resin molding that it is easy to partially cool. Furthermore, there is a problem that the temperature of the plunger waiting on the bottom side of the pot is likely to be lowered. Due to these factors, there is a problem that the cycle time required for the resin mold becomes long.

  The object of the present invention is to solve the above-mentioned problems of the prior art, and to improve the filling property of the mold resin by applying the final resin pressure to the narrow mold space in the magnet insertion hole without increasing the clamping force to the motor core. Another object of the present invention is to provide a resin molding method of a motor core that can improve productivity and improve motor characteristics by using this.

In order to achieve the above object, the present invention comprises the following arrangement.
A resin mold apparatus in which a motor core having a magnet inserted into a magnet insertion hole is sandwiched between mold dies, and a mold resin and the magnet are resin-molded integrally with the motor core in the magnet insertion hole, wherein the motor core is mounted. Overflow cavities connected to the opening of the magnet core insertion hole of the motor core are respectively formed in one of the fixed mold placed and the movable mold that clamps the motor core, and the overflow mold resin is filled in the overflow cavity. A movable member to be pushed back to the magnet insertion hole is provided.

  According to the above configuration, the mold resin overflowing into the overflow cavity connected to the opening of each magnet insertion hole of the motor core can be pushed back to the magnet insertion hole by the movable member. As a result, when the mold resin is filled in the narrow space of the magnet insertion hole, it can be filled uniformly with the overflow of the overflow cavity, and the mold insertion space can be narrowed without increasing the clamping force on the motor core. Since the final resin pressure can be applied to the supplied mold resin and the filling density of the resin can be increased, even if bubbles are mixed, it can be eliminated and the unfilled area can be eliminated. In addition, resin filling can be promoted by providing an air vent connected to the overflow cavity.

The overflow cavity is preferably an upper space of the movable member formed by being supported at a position where the movable member is lowered from an upper end of an insertion hole provided corresponding to the magnet insertion hole.
As a result, by using the insertion hole of the movable member provided corresponding to the magnet insertion hole as the overflow cavity, special mold processing is unnecessary, and the mold resin overflowing into the overflow cavity with a simple configuration is inserted into the magnet. Can be pushed back into the hole.

  It is preferable that the movable member is supported by a drive source via a support plate so as to be movable up and down. As a result, the drive source is activated and the plurality of movable members supported via the support plate are pushed up to the upper end of the insertion hole, and the mold resin overflowing into each overflow cavity can be efficiently pushed back to the magnet insertion hole.

  In a resin molding method for a motor core, a step of preparing a motor core in which a plurality of magnet insertion holes are formed, a step of preheating the motor core to a predetermined temperature close to the heating temperature of the mold, and each magnet insertion hole of the motor core Clamping the mold resin and magnet supplied to the mold mold to overflow the mold resin into the overflow cavity communicating with each magnet insertion hole of the mold mold, and the mold resin in the overflow cavity to the mold resin And pressing the magnet back into the magnet insertion hole to heat and cure at a predetermined temperature while applying resin pressure, and molding the magnet integrally with the motor core.

  As a result, when the mold resin is filled into the narrow space of the magnet insertion hole, it is possible to uniformly fill with overflow of the overflow cavity and to push the mold resin overflowing the overflow cavity back into the magnet insertion hole to the motor core. Without increasing the clamping force, the final resin pressure can be applied to increase the resin filling density, and the resin mold can be performed without an unfilled region.

  An insertion hole is provided corresponding to each of the magnet insertion holes, and a mold resin overflowing into the overflow cavity by pushing up a movable member provided in each insertion hole by a driving source until it is flush with the insertion holes. Is preferably pushed back into the magnet insertion holes. Thereby, the filling property of mold resin can be improved with respect to a some magnet insertion hole, and productivity can be improved.

  When the resin molding apparatus and the motor core resin molding method described above are used, when the mold resin is filled into the narrow space of the magnet insertion hole, it can be uniformly filled with overflow of the overflow cavity, and the magnet insertion hole is narrow. The final resin pressure can be applied to the mold resin supplied to the mold space without increasing the clamping force on the motor core to increase the resin filling density. . In addition, since the resin filling property into a narrow mold space with a plurality of provided magnet insertion holes is improved, the productivity of the motor core can be improved and the motor characteristics can be improved.

It is explanatory drawing which inserts a magnet in a motor core, and explanatory drawing in the case of setting an annular heat insulation member and an intermediate | middle plate in the motor core mounted in the conveyance plate. FIG. 2 is a perspective explanatory view showing a process of preheating the motor core of FIG. 1 in a heating furnace. FIG. 3 is a perspective explanatory view showing a resin molding process following FIG. 2. FIG. 4 is a perspective explanatory view showing a resin molding step following FIG. 3. FIG. 5 is a perspective explanatory view illustrating a resin molding process subsequent to FIG. 4. FIG. 6 is a perspective explanatory view illustrating a resin molding process subsequent to FIG. 5. FIG. 7 is a perspective explanatory view illustrating a resin molding process subsequent to FIG. 6. FIG. 8 is a perspective explanatory view showing a degate process following FIG. 7. FIG. 9 is a perspective explanatory view illustrating a degate process subsequent to FIG. 8. It is a transparent explanatory drawing which shows the separation of the unnecessary resin from the intermediate plate and the cleaning process. It is transparent explanatory drawing of the resin mold apparatus which concerns on another example.

  Hereinafter, preferred embodiments of a resin molding apparatus and a motor core resin molding method according to the present invention will be described in detail with reference to the accompanying drawings. In the following, a permanent magnet type rotor (rotor) core will be described as a motor core. The motor core is not limited to the motor core, and may be a stator core.

  The rotor includes a shaft (not shown), a motor core 1 supported by the shaft, and a magnet 3 inserted into the magnet insertion hole 2 of the motor core 1. As shown in FIG. 1A, the motor core 1 is provided with a central through hole 1a into which a shaft (not shown) is inserted. The magnet 3 is, for example, a magnetic body block before magnetization, and a neodymium magnet or a ferrite magnet is used. As the motor core 1, for example, a laminated core (laminated iron core) in which plate-like magnetic bodies such as electromagnetic steel plates punched by press working are laminated is used.

  In FIG. 1B, a protrusion 4 a is positioned on the transport plate 4 so as to be positioned. The motor core 1 is placed by fitting a concave portion corresponding to the caulking portion of the motor core 1 to the protruding portion 4a. Further, an inner through hole 4b and an outer through hole 4c for release are provided on the motor core mounting region of the transport plate 4 and the outer peripheral side thereof. The motor core 1 is placed on the transport plate 4 and placed on a fixed mold with an intermediate plate 6 to be described later overlaid.

  The annular heat insulating member 5 is placed so as to cover the outer peripheral side of the motor core 1 of the transport plate 4. The annular heat insulating member 5 is formed by connecting an annular outer peripheral member 5a and an outer peripheral member 5b with a coil spring 5c interposed. As the outer peripheral members 5a and 5b, members having high heat insulating properties and heat storage properties are used. The coil spring 5c is provided so that no gap is generated even when the thickness of the motor core 1 changes when clamped on the mold. The outer peripheral members 5a and 5b are provided with a through hole 5d communicating with the outer peripheral side through hole 4c. An annular heat insulating member 5 is placed concentrically on the transport plate 4 so as to cover the outer periphery of the motor core 1, and the intermediate plate 6 is overlaid. The annular heat insulating member 5 may be configured to insulate from the outside air while being separated from the outer periphery of the motor core 1 as described above, but as a configuration to insulate the outside air from being in contact with the outer periphery of the motor core 1, It is good also as a structure which improves or prevents the expansion of the motor core 1 by resin pressure.

  The intermediate plate 6 is formed in a state in which a sprue plate 6b made of a non-metallic material (such as a ceramic material) is fitted into a plate body 6a made of a steel material in a portion corresponding to a resin flow path. A stepped portion 6e is formed in the plate body 6a as a side surface (hole wall surface) of a hole into which the sprue plate 6b can be inserted, and the sprue plate 6b is aligned and fitted into the stepped portion 6e. The plate body 6a is preferably made of a material having a uniform linear expansion coefficient (for example, a steel material) for use in combination with another mold. For example, the sprue plate 6b is preferably made of, for example, high-strength zirconia (ZrO2), and ceramic such as silicon nitride (Si3N4) or silicon carbide (SiC) can also be used. The sprue plate 6b may be formed using a low adhesion material using a rare earth oxide made of any one of Y2O3, Gd2O3, Sm2O3, Eu2O3, Er2O3, Yb2O3, and Lu2O3. Furthermore, the sprue plate 6b can further improve the mold releasability of the mold resin by applying a coating such as surface treatment or application of a release agent as necessary. The sprue plate 6b may be made of another material such as a steel material that has been subjected to a surface treatment such as plating as long as it has a high releasability from the mold resin.

  Further, on both surfaces of the sprue plate 6b, portions other than the resin flow region are clamped by the mold or the motor core 1. Therefore, when the sprue plate 6b is formed of a brittle material such as a ceramic material, a region clamped by the mold or the motor core 1 (in other words, a region other than the resin flow region) is clamped via an elastic body, for example. Thus, it is possible to perform clamping with an appropriate clamping force while preventing resin leakage, and it is also possible to prevent breakage of the brittle material. For this reason, it is good also as a structure which affixed the elastic body on the required part in the sprue plate 6b, for example. As an example of the elastic body, when a heat-resistant silicon material is used, it can be used withstanding repeated molding, and the running cost can be reduced. The elastic body may be re-applied for each molding.

In the sprue plate 6b, a sprue 6c penetrating in the thickness direction is formed in a region not overlapping the magnet insertion hole 2 in plan view. On the lower surface side of the sprue plate 6b, a communication groove 6d that connects the sprue 6c and the magnet insertion hole 2 is engraved. The sprue 6c is connected to an upper runner described later on the upper surface side of the intermediate plate 6, and is connected to the sprue 6c and the communication groove 6d on the lower surface side of the intermediate plate 6.
Further, the intermediate plate 6 is formed with a relief recess (not shown) for allowing the caulking part (convex part) of the motor core 1 to escape. The escape recess may be formed in either the plate body 6a or the sprue plate 6b.

Next, the structure of the resin mold apparatus will be described with reference to FIG.
The lower die 7 is a fixed die, and is placed in alignment with the lower die clamping surface in a state where the motor core 1 and the annular heat insulating member 5 are superimposed on the conveying plate 4.
The lower mold 7 includes a lower mold heater 7a. By making the lower mold 7 a fixed mold, the production line can be designed to the same height. For example, in a resin molding apparatus, when pulling in from a conveyor mechanism provided adjacently in a manufacturing apparatus equipped with a resin molding apparatus, the motor core 1 can be carried in and out with little up and down, which is preferable.

  The upper mold 8 is a movable mold and moves toward and away from the lower mold 7 through a mold opening / closing mechanism (not shown). The upper mold 8 includes a pot 9 and a plunger 10 that clamp the motor core 1 via the intermediate plate 6 and are supplied with mold resin. Specifically, the upper mold 8 has a pot block 11 in which a plurality of pots 9 are formed. The plurality of pots 9 are arranged at predetermined intervals in the circumferential direction with respect to the center of the upper mold 8, and mold resin 22 (see FIG. 4) is applied to one or a plurality of adjacent magnet insertion holes 2. Used to supply. Moreover, the utilization rate of the mold resin 22 can be improved by arranging the pot 9 near the magnet insertion hole 2. The pot block 11 is formed with an upper runner 11a communicating with the pot 9 and the sprue 6c, and a first heater 11b (first heat source) is built therein. The pot block 11 is suspended and supported by a guide post 13 with respect to the upper mold base 12. In addition, the runner board 11c in which the upper runner 11a was carved may be provided in the clamp surface side of the pot block 11 so that isolation | separation is possible. In this case, it is possible to cope with the product type change only by exchanging the runner plate 11c and the intermediate plate 6, and the setup change can be minimized. Further, the plate body 6a can be used as it is, and only the sprue plate 6b can be changed to cope with a change in product type.

  The movable block 14 is disposed between the upper mold base 12 and the pot block 11, and pre-heats the plunger 10 by the second heater 14b (second heat source). The movable block 14 is moved toward and away from the pot block 11 in conjunction with the lifting and lowering operation of the plunger 10. In addition, it is good also as a structure which guides raising / lowering of the plunger 10 with the guide cylinder 14a.

  The movable block 14 is assembled with the guide post 13 passing therethrough. Both sides of the movable block 14 are held by holding parts 15, and the holding parts 15 are connected to a drive source 17 (motor) via a shaft 16. When the drive source 17 is activated, the movable block 14 held by the holding portion 15 via the shaft 16 is guided by the guide post 13 and moves up and down. Instead of moving up and down using the drive source 17, the movable block 14 is suspended and supported by a support block 18 that supports the plunger 10 with a spring or the like while maintaining a predetermined distance, so that the plunger 10 and the movable block 14 are supported. May be moved up and down at the same time.

  The plunger 10 is suspended and supported by the support block 18. The distal end side of the plunger 10 is inserted into the guide cylinder 14a of the movable block 14 and preheated by the second heater 14b. In order to equalize the applied pressure, the plunger 10 is supported by being suspended, for example, via a coil spring 18a. Further, the support block 18 is connected to the pressing rod 19. The pressing rod 19 is moved up and down by a drive source 20 (motor) connected through the upper mold base 12. The driving source 20 and the driving source 17 are driven in synchronization, and the plunger 10 and the movable block 14 are moved up and down in conjunction with each other.

Next, an example of a resin core molding method will be described with reference to FIGS.
First, as shown in FIG. 1A, a motor core 1 is prepared in which a magnet 3 is inserted into a magnet insertion hole 2 so as to be close to the radially inner hole wall surface. The magnet 3 is inserted into the magnet insertion hole 2 so that, for example, two rectangular parallelepiped magnets are arranged in series. The magnet 3 may be inserted near the hole wall surface on the radially outer side of the magnet insertion hole 2. In this case, for example, alignment can be performed by sandwiching an elastic body or a jig between the magnet 3 and the hole wall surface of the magnet insertion hole 2. In addition, it is good also as a structure which protrudes a part of iron core from the magnet insertion hole 2, and fixes the magnet 3. FIG.

  Next, as shown in FIG. 1B, the motor core 1 is positioned and placed on the protrusion 4 a on the transport plate 4. In this case, positioning may be performed by providing a protrusion at the center of the transport plate 4 and fitting in the center through hole 1a. Subsequently, an annular heat retaining member 5 is placed on the outer peripheral side so as to surround the motor core 1, and the intermediate plate 6 is overlaid thereon.

  Next, as shown in FIG. 2, the motor core 1, the annular heat insulating member 5, and the intermediate plate 6 are superposed on the motor plate 1 on the transport plate 4. Preheated to a temperature (approximately around 200 ° C.).

  As shown in FIG. 3, the motor core 1 preheated to a predetermined temperature is transported to the lower mold 7 that is opened and positioned while being mounted on the transport plate 4. At this time, the movable block 14 of the upper mold 8 is in a retracted position separated from the pot block 11, and the distal end side of the plunger 10 is preheated by the second heater 14a while being inserted into the guide cylinder 14a.

  Next, as shown in FIG. 4, the upper die 8 is closed and the intermediate plate 6 is clamped by the pot block 11. In this state, using the work space formed between the pot block 11 and the movable block 14, the transfer device 21 (loader, robot hand, etc.) indicated by the broken line is entered to enter the pot 9 with the mold resin 22 (for example, resin). Tablet). As an example, the transport device 21 includes an accommodation hole for the mold resin 22 and a lid portion provided on the lower surface of the mold resin 22 in substantially the same layout as the pot 9, and performs transport and supply by opening and closing the lid portion. It can be configured. The mold resin 22 is heated and melted by the first heater 11 b provided in the pot block 11.

  Next, the drive source 20 and the drive source 17 (see FIG. 3) are activated, and the support block 18 and the plunger 10 are moved downward via the pressing rod 19 as shown in FIG. Then, the movable block 14 is moved down to a position where it overlaps the pot block 11. At this time, the guide tube 14 a and the pot 9 overlap each other and communicate with each other, and the tip of the plunger 10 enters the pot 9 and comes into contact with the mold resin 22. Further, the plunger 10 and the mold resin 22 are heated by the first heater 11b and the second heater 14b.

  Next, the drive source 20 (see FIG. 3) is further driven, and as shown in FIG. 6, the support block 18 and the preheated plunger 10 are further moved downward via the pressing rod 19, and the pot 9 is moved. The melted mold resin 22 is filled into the magnet insertion hole 2 through the upper mold runner 11a, the sprue 6c and the communication groove 6d. The magnet 3 is formed integrally with the motor core 1 by heating and curing the mold resin 22 at a predetermined temperature.

  Next, the drive source 20 and the drive source 17 (see FIG. 3) are driven in reverse rotation to retract the plunger 10 and the movable block 14 from the pot block 11 as shown in FIG. Open the mold 8. At this time, the lower surface of the movable block 14, the upper surface of the pot block 11, and the lower surface of the pot block 11 (the lower surface of the runner plate 11c) are cleaned using a cleaning brush (not shown). Further, the unnecessary resin 23 hardened by the upper mold runner 11a and the upper mold cull (not shown) is released from the mold while being attached to the intermediate plate 6 integrally.

  Next, the motor core 1 is taken out together with the transport plate 4 from the opened lower mold 7 and transported to the degate device 24. Before the motor core 1 is transported to the degate device 24, the transport plate 4 may be transported to the cooling device and cooled to a predetermined temperature (for example, room temperature) before being transported to the degate device 24. Further, after the motor core 1 is degated by the degate device 24, the motor core 1 may be carried into a cooling device and cooled to a predetermined temperature (for example, normal temperature) and stored.

  In FIG. 8A, in the delegation device 24, an inner delegation pin 24a and an outer delegation pin 24b project from the base plate 24c in the radial direction from the center. The inner delegate pin 24a and the outer delegate pin 24b are arranged in a concentric circle, for example. A movable support plate 24e is supported on the base plate 24c via a coil spring 24d. The inner delegate pin 24a and the outer delegate pin 24b protrude through the movable support plate 24e.

  As shown in FIG. 8A, the motor core 1 is placed on the movable support plate 24e together with the transport plate 4. At this time, the inner delegate pin 24 a is inserted into the inner through hole 4 b, the outer delegate pin 24 b is inserted into the outer through hole 4 c, and the outer delegate pin 24 b is inserted up to the through hole 5 d of the annular heat insulating member 5.

  Next, as shown in FIG. 8B, when the movable support plate 24e (or the transport plate 4) is pushed down, the inner delegate pin 24a reaches the motor core 1, and the outer delegate pin 24b pushes up the intermediate plate 6. As shown in the figure, the intermediate plate 6 and the mold resin 22 filled in the motor core 1 are separated. In this case, since the sprue plate 6b supported by the stepped portion 6e can be ganged together by pushing up the intermediate plate 6, it is possible to reliably dig with a simple configuration. In the present embodiment, in order not to remove the unnecessary resin 23a at this stage, the sprue plate 6b is digged away so as to be broken at the boundary between the sprue 6c and the communication groove 6d.

  Further, by depressing the transport plate 4, the motor core 1 is separated from the transport plate 4 as shown in FIG. Then, as shown in FIG. 9B, the motor core 1 is removed from the transport plate 4 after removing the intermediate plate 6. At this time, the unnecessary resin 23 (molded product cul, molded product runner) is integrally formed on the intermediate plate 6, and the unnecessary resin 23 a corresponding to the molded product gate remains in the motor core 1. In this way, since the sprue 6c is not directly connected to the magnet insertion hole 2, the mold resin filled in the magnet insertion hole 2 is reduced by reducing the risk of microcracking in the magnet insertion hole 2 due to the impact of delegation. The strength of 22 can be improved.

  The unnecessary resin 23 remaining on the surface of the motor core 1 is removed by, for example, laser irradiation according to specifications. For this reason, the resin molding apparatus includes a laser irradiation unit and a residual resin removal unit (not shown) that sublimates and removes the unnecessary resin 23a remaining on the surface of the resin-molded motor core 1 by irradiating the laser. It is preferable.

  In this case, since a metal material or the like is moved along the surface of the mold resin 22 and the remaining unnecessary resin 23a is scraped off, the removal operation can be performed without applying vibration. The high performance motor core 1 can be provided without impairing the close contact state of the mold resin 22 in the hole 2. In addition, when the mold resin 22 leaked to the periphery (for example, air vent) in the magnet insertion hole 2 remains on the surface of the motor core 1 by the residual resin removing portion, it may be removed together. Further, when the mold resin 22 remains as a thin film on the end face of the magnet 3 and peeling in a later process becomes a problem, it may be removed together. In this case, the remaining resin removal unit may be configured to include a pair of laser irradiation units facing both surfaces of the motor core 1 so that the mold resin 22 remaining on the both surfaces of the motor core 1 can be removed.

In FIG. 10A, after the unnecessary resin 23 is separated from the intermediate plate 6 by pushing up the unnecessary resin 23 from the lower surface side of the sprue 6c, for example, as shown in FIG. You may have the process cleaned using a pair of cleaning brush 25 grade | etc.,.
Thereby, the intermediate plate 6 after resin molding can be cleaned and reused, and the production efficiency can be improved. In this case, for example, the sprue plate 6b is removed from the intermediate plate 6 and only the sprue plate 6b is cleaned, and the plate body 6a can be reused as it is. As a result, by preparing a large number of sprue plates 6b, the sprue plate 6b and the sprue plate 6b, which are extremely dirty in the sprue 6c and the communication groove 6d, can be replaced and used, or the cleaning takes a sufficiently long time for one cycle of the molding process. It is possible to improve the molding quality by reliably performing cleaning.

Next, another example of the resin molding apparatus will be described with reference to FIGS. The same members as those in the resin mold apparatus described above are denoted by the same reference numerals, and the description is incorporated. In the following, different configurations will be mainly described.
In FIG. 11A, the transport plate 4 is provided with a plurality of pin insertion holes 4 d (through holes) corresponding to the magnet insertion holes 2. A movable pin 26 (movable member) is inserted into each pin insertion hole 4d. When the transport plate 4 is not used, the lower mold 7 may be provided with a pin insertion hole and a movable pin.

  The lower mold 7 is formed with a lower mold insertion hole 7b communicating with the pin insertion hole 4d. Support pins 27 are inserted into the lower mold insertion holes 7b. Each support pin 27 is integrally supported by a movable support plate 29 provided in the lower mold 7. The movable pin 26 is supported by the support pin 27 so that the upper end portion of the pin is positioned lower than the upper end of the pin insertion hole 4d. An upper space (concave portion) of the movable pin 26 inserted into the pin insertion hole 4d becomes an overflow cavity 28. The movable pin 26 and the support pin 27 connected to the movable pin 26 are circularly arranged with a predetermined interval corresponding to the arrangement of the magnet insertion holes 2 of the motor core 1.

  There are a plurality of magnet insertion holes 2 provided in the motor core 1, the volumes in the magnet insertion holes 2 vary, and the magnet 3 may be fixed in the magnet insertion hole 2 without using a fixing member provided in the mold. is there. For this reason, it is not easy to make the gap (clearance) in the magnet insertion hole 2 constant. Therefore, by filling the mold resin 22 exceeding the gap (volume) between the magnet insertion hole 2 and the magnet 3, the filling state of the mold resin 22 filled in all the magnet insertion holes 2 can be made uniform without filling the overflow cavity 28. The mold resin 22 is surely filled with overflow. Further, even if a void remains in the magnet insertion hole 2 in the filling process, it can be reliably discharged to prevent unfilling. In addition, filling can be promoted by providing an air vent (not shown) so as to connect to the overflow cavity 28.

  The movable support plate 29 is supported by the wedge mechanism 30 so as to be movable up and down. The movable support plate 29 is supported by a pair of left and right support pieces 31. Each support piece 31 is supported by a movable piece 32 and tapered surfaces which are inclined toward the left and right ends from the center of the apparatus. The wedge mechanism 30 is configured such that the movable piece 32 moves backward on the lower mold base 34 when the screw shaft 33a is rotated by a drive source 33 (motor). The drive source 33 is not limited to a motor, and may be another drive source such as a solenoid or a cylinder. Alternatively, the movable support plate 29 may be directly driven in the ascending / descending direction by another drive source such as a solenoid or a cylinder.

  As shown in FIG. 11A, with the mold closed, the plunger 10 is moved downward to fill the magnet insertion hole 2 with the mold resin 22 melted in the pot 9 through the upper mold runner 11a, the sprue 6c and the communication groove 6d. To do. At this time, the mold resin 22 overflows into the overflow cavity 28 on the opposite side to the mold resin injection direction of the magnet insertion hole 2.

  Next, as shown in FIG. 11B, when the drive source 33 of the wedge mechanism 30 is activated to move the movable piece 32 from the center of the lower mold 7, the movable piece 32 moves the support piece 31 along the tapered surface. The movable pin 26 is pushed up to a position flush with the pin insertion hole 4d through the support pin 27 erected on the movable support plate 29. At this time, the mold resin 22 overflowing into the overflow cavity 28 is pushed back to the magnet insertion hole 2 and the final resin pressure is maintained. Thereby, even if air bubbles are mixed into the mold resin 22, it can be eliminated and the unfilled area in the magnet insertion hole 2 can be eliminated. In other words, the strength of the mold resin 22 in the magnet insertion hole 2 can be increased by increasing the filling density of the mold resin 22. In this state, the molding resin 22 can be heated and cured at a predetermined temperature to mold the magnet 3 integrally with the motor core 1, thereby improving the molding quality. Therefore, the mold resin 22 can be reliably filled into a narrow gap between the magnet 3 inserted into the magnet insertion hole 2 and the hole wall surface. Further, when the mold resin 22 is peeled off from the hole wall surface of the magnet insertion hole 2 when the mold is opened due to the spring back of the motor core 1 when the mold is opened, the mold resin is used when the clamping force is reduced in the mold clamping state. Such a problem can be improved by further filling 22.

As described above, the sprue 6c connected to the upper runner 11a and penetrating in the plate thickness direction is formed, and the intermediate plate 6 is formed with the communication groove 6d communicating the sprue 6c and the magnet insertion hole 2. Since the motor core 1 is clamped to the mold, even if the arrangement of the magnet insertion holes is changed by exchanging the product type of the motor core 1, it is possible to cope with it simply by replacing the intermediate plate 6. In addition, the equipment operation rate is improved.
Moreover, since the movable block 14 which preheats the plunger 10 with the 2nd heater 14b is provided, the temperature fall of the preheated plunger 14 can be suppressed as much as possible.
In addition, the movable block 14 is moved toward and away from the pot block 11 in conjunction with the raising and lowering operation of the plunger 10, so that when the mold resin is supplied to the pot 9 of the pot block 11, the movable block 14 is retracted. A sufficient working space can be formed. In addition, when the mold resin 22 is injected, the plunger 10 preheated with the movable block 14 superimposed on the pot block 11 can be allowed to enter the pot 9 as it is. Can be shortened.

In the resin mold apparatus, the upper mold is described as a movable mold and the lower mold as a fixed mold. However, the upper mold may be a fixed mold, the lower mold may be a movable mold, or both may be movable molds. Further, the lower mold 7 and the upper mold 8 may be configured upside down. In this case, the plunger 10 and the mold resin 22 can be accommodated in the movable block 14, and the motor core 1 is molded in a state where it is mounted on the pot block 11 via the intermediate plate 6 in which the stepped portion 6e is formed in the opposite direction. Will do.
In addition to the intermediate plate 6 and the motor core 1, a mold resin 22 (resin tablet) is pre-heated in advance before being carried into the mold, and is provided in the press section by a conveying means such as a loader or a robot. It is preferable to be carried into the mold.

  In addition, a convex portion may be provided in the center of the lower surface of the plate body 6a for insertion into the central through hole 1a of the motor core 1 for positioning. In this case, when a key groove is formed in the central through hole 1a, a protrusion for fitting the key through the key groove and adjusting the angle may be provided in the central through hole 1a. Similarly, by providing a convex portion or a concave portion on the upper surface of the plate main body 6a, positioning may be performed by fitting with a convex portion or a concave portion provided on the central lower surface of the runner plate 11c, and the center may be aligned. According to these configurations, the communication groove 6d and the magnet insertion hole 2 can be accurately positioned with a simple configuration. Further, since positioning is performed with reference to a position close to the sprue 6c and the communication groove 6d, accurate positioning is possible. When a convex portion is provided at the center of the plate body 6a, an insertion hole sufficiently larger than the central through hole 1a of the motor core 1 is provided at the center of the plate body 6a, and a member having the convex portion is fitted into the insertion hole. It is good also as a structure to match. In this case, it is possible to easily cope with a change in the type of the motor core 1 (change in the shape of the central through hole 1a).

  Moreover, it is good also as a structure using the conveyance plate 4 which has replaced the said conveyance plate 4 and has arrange | positioned the positioning shaft part which can be inserted in the center through-hole 1a of the motor core 1 on the upper surface. In this case, it can be set as the structure which supports the member fitted by an elastic member (for example, spring) so that it can respond to the change of the thickness of the motor core 1 by pressurization. In this case, for example, the upper and lower members of the motor core 1 may be aligned (centered) by providing a hole in the plate body 6a and inserting it into the hole.

  Moreover, although the structure which enables the runner board 11c to be separable with respect to the pot block 11 was demonstrated, the shape corresponded to the runner board 11c may be dug into the lower surface of the pot block 11 at groove shape. Further, the runner plate 11 c may be transported while being stacked on the intermediate plate 6. In this case, contrary to the above-described runner plate 11c, the shape of the upper runner 11a is preferably formed so that the upper side is widened so that the mold can be easily released.

  Further, the above-described sprue plate 6b is aligned with the plate body 6a by being inserted into the stepped portion 6e. However, the present invention is not limited to this. For example, positioning can be performed by inserting two or more pins standing on the lower surface of the runner plate 11c into two or more through holes provided in the sprue plate 6b at the same interval. In this case, when it is difficult to insert a pin due to the difference in linear expansion coefficient, positioning can be performed by using one round hole and a long hole extended in the longitudinal direction with respect to the round hole as the other hole. In this case, it is preferable that the sprue plate 6b is sufficiently small relative to the stepped portion 6e to be movable within the stepped portion 6e. Thus, for example, when the runner plate 11c is conveyed over the intermediate plate 6, even if the runner plate 11c is made of a different material such as a steel plate and the sprue plate 6b is ceramic, accurate positioning is possible without damage. Is possible.

  The above-described sprue plate 6b is fitted into the plate body 6a by the stepped portion 6e. Instead, the side surface of the sprue plate 6b is tapered, and the plate body 6a is provided with a tapered hole extending upward so that the tapered sprue plate 6b can be fitted, and positioning is performed by fitting the tapers together. be able to.

  Further, in the sprue plate 6b, the above-described sprue 6c is connected to the magnet insertion hole 2 via the communication groove 6d, but the present invention is not limited to this. For example, the sprue 6c may be directly connected to the magnet insertion hole 2 without providing the communication groove 6d. Alternatively, the mold resin 22 may be separated in the sprue 6c by configuring the sprue 6c to have the smallest diameter at an intermediate position in the length direction. Thereby, the risk of the occurrence of microcracks in the magnet insertion hole 2 can be reduced. Further, when the communication groove 6d is not provided, the unnecessary resin 23 at the time of delegation protrudes from the magnet insertion hole 2 by inserting the sprue 6c into the magnet insertion hole 2 by projecting the outer periphery on the front end side (lower end side). As a result, the removal work of the unnecessary resin 23 is unnecessary, and the production cost can be reduced. Furthermore, it is good also as a structure which provides the runner which connects the pot 9 and the sprue 6c on the upper surface of the sprue plate 6b.

  DESCRIPTION OF SYMBOLS 1 Motor core 1a Center through-hole 2 Magnet insertion hole 3 Magnet 4 Conveyance plate 4a Protrusion part 4b Inner through-hole 4c Outer through-hole 4d Pin insertion hole 5 Annular heat insulating member 5a, 5b Outer peripheral member 5c Coil spring 5d Through-hole 6 Intermediate plate 6a Plate Main body 6b Sprue plate 6c Sprue 6d Communication groove 7 Lower die 7a Lower die heater 8 Upper die 9 Pot 10 Plunger 11 Pot block 11a Upper die runner 11b First heater 11c Runner plate 12 Upper die base 13 Guide post 14 Movable block 14a Guide Tube 14b Second heater 15 Holding portion 16 Shafts 17 and 20 Drive source 18 Support block 18a Coil spring 19 Press rod 21 Conveying device 22 Mold resin 23 Unnecessary resin 24 Igeto device 25 cleaning brush 26 movable pin 27 support pins 28 overflow cavity 29 movable support plate 30 a wedge mechanism 31 supporting members 32 movable dies 33 drive source 33a screw shaft 34 the lower mold base

Claims (5)

A resin mold apparatus in which a motor core having a magnet inserted into a magnet insertion hole is sandwiched between mold dies, and a mold resin and the magnet are resin-molded integrally with the motor core in the magnet insertion hole,
An overflow cavity connected to the opening of the magnet core insertion hole of the motor core is formed in either one of the fixed mold on which the motor core is placed and the movable mold that clamps the motor core, and the overflow cavity has an overflow A resin molding apparatus, wherein a movable member is provided to push the molded resin back into the magnet insertion hole.   2. The resin mold according to claim 1, wherein the overflow cavity is an upper space of the movable member formed by being supported at a position where the movable member is lowered from an upper end of an insertion hole provided corresponding to the magnet insertion hole. apparatus.   The resin mold apparatus according to claim 1, wherein the movable member is supported by a drive source via a support plate so as to be movable up and down. Preparing a motor core in which a plurality of magnet insertion holes are formed;
Preheating the motor core to a predetermined temperature close to the heating temperature of the mold,
Clamping the mold resin and magnet supplied to each magnet insertion hole of the motor core with a mold, and allowing the mold resin to overflow into an overflow cavity communicating with each magnet insertion hole of the mold;
Pressing the mold resin in the overflow cavity back into the magnet insertion hole and applying the resin pressure to heat and cure at a predetermined temperature, and molding the magnet integrally with the motor core;
A resin mold method for a motor core, comprising:   An insertion hole is provided corresponding to each of the magnet insertion holes, and a mold resin overflowing into the overflow cavity by pushing up a movable member provided in each insertion hole by a driving source until it is flush with the insertion holes. The resin molding method of the motor core according to claim 4, wherein each is pushed back into each of the magnet insertion holes.

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