JP2017159624A - Insert molding method and insert molding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insert molding method and an insert molding apparatus, in which deformation of an insert component is prevented, and contamination of a foreign substance can be prevented.SOLUTION: In the insert molding method including injecting and molding a resin 13 from a gate 27 to embed the resin 13 with an insert component 11, the resin 13 is injected so that a difference in the pressure of the resin 13 between a first side 12a of the insert component 11, which is arranged on a side of the gate 27, and a second side 12b of the insert component 11, which is arranged on a side opposite to the gate 27 is in a specified range. At least one or more conditions of the filling rate of the resin 13, the temperature of a die surface 29 around the insert component 11, the position of the gate 27, the size of the gate 27, and the position of the insert component 11 are determined so that pressures at plural points set around the insert component 11 can be maintained in the state of being roughly uniform, and molding is performed using the determined conditions.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an insert molding method and an insert molding apparatus.

2. Description of the Related Art Conventionally, in insert molding, a technique for deforming an insert part or holding an insert part at a predetermined position in a resin is known.
Patent Document 1 discloses a technique for preventing deformation of an insert component by filling a resin with a crank-shaped flow path to reduce the speed and pressure of the inflowing resin.
Patent Document 2 discloses a technique in which an insert part is floated from a mold by a pin and the pin is retracted into the mold in the middle of resin filling so that the insert part is held at a predetermined position in the resin. .

Japanese Patent No. 4122411 JP 2013-107286 A

  However, in conventional insert molding, deformation of the insert part may not be sufficiently prevented even if the speed and pressure of the resin are reduced. Further, for example, as in Patent Document 2, if the deformation is prevented by being firmly supported by the pin, the molding quality of the portion supported by the pin is lowered. Further, when the pin is retracted into the mold in the middle of resin filling, a piece may be generated from a contact portion between the insert part and the pin and mixed as a foreign substance in the resin.

  Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide an insert molding method and an insert molding apparatus that can prevent the deformation of insert parts and prevent the introduction of foreign matters.

  In order to solve the above-described problem, an insert molding method according to the first aspect of the present invention includes an insert part (for example, the insert part 11 of the embodiment) disposed in a mold (for example, the mold 21 of the embodiment), In the insert molding method of embedding the insert part in the resin by injecting and molding a resin (for example, the resin 13 of the embodiment) from a gate (for example, the gate 27 of the embodiment), the insert disposed on the gate side The resin between the first side surface of the part (for example, the first side surface 12a of the embodiment) and the second side surface of the insert part (for example, the second side surface 12b of the embodiment) disposed on the opposite side of the gate. The resin is injected so that the pressure difference falls within a predetermined range.

According to this configuration, since the resin is injected so that the pressure difference of the resin is within a predetermined range between the first side surface disposed on the gate side and the second side surface disposed on the opposite side of the gate, The pressure difference between both side surfaces of the insert part can be set in a small range, and the insert part can be prevented from being deformed. Therefore, it is possible to prevent the insert part from being deformed into an unexpected shape during insert molding. Moreover, it can prevent that the insert components embed | buried in resin are exposed outside by the pressure difference at the time of insert molding. Further, the pressure between both side surfaces of the insert part may be adjusted, and foreign matter such as a chip is not generated by contact of the insert part, the mold, the pin, or the like.
Therefore, it is possible to provide an insert molding method capable of preventing the insert parts from being deformed and preventing foreign matters from being mixed.

  Further, in the insert molding method according to the second aspect of the present invention, the filling speed of the resin and the insert so as to maintain the pressure at a plurality of points set around the insert part in a substantially uniform state. Determining at least one condition of a mold surface around the part (for example, the mold surface 29 of the embodiment), the position of the gate, the size of the gate, and the position of the insert part; The molding is performed using the determined conditions.

  According to this configuration, the speed of resin filling, the temperature of the mold surface around the insert part, the position of the gate, the size of the gate, and the insert part so as to maintain the pressure at a plurality of points in a substantially uniform state. Since the molding is performed using any one of the conditions of the position, it is possible to prevent the insert part from being deformed and to be easily disposed at a desired position in the resin, and to prevent foreign matters from being mixed.

  Further, in the insert molding method according to the third aspect of the present invention, the mold surface around the insert part is heated by a heater (for example, the heater 31 of the embodiment) provided on the second side surface of the mold. It is characterized by adjusting the temperature.

According to this configuration, the mold surface on the second side surface of the mold is heated by the heater to adjust the temperature of the mold surface. Therefore, when the molten resin comes into contact with the mold surface on the second side surface, the temperature of the resin Does not drop abruptly or the viscosity rises abruptly.
Therefore, the second side surface can be made to flow to the same extent as the first side surface side, and the pressure applied from the resin to the first side surface of the insert part can be made equal to the pressure applied to the second side surface.
Therefore, deformation of the insert part toward the side surface can be prevented.

  In the insert molding method according to the invention described in claim 4, the distance between the mold surface having the largest number of gates and the first side surface of the insert part is set between the second side surface and the second side surface. The initial position of the insert part is adjusted so as to be smaller than the distance between the opposing mold surfaces.

  According to this configuration, the distance between the mold surface having the largest number of gates and the first side surface of the insert part is made smaller than the distance between the second side surface of the insert part and the mold surface facing the second side surface. Since the initial position is adjusted, the molten resin can be made to flow positively between the second side surface and the mold surface facing the second side surface, and the pressure applied to the second side surface is increased to the same level as the first side surface. Can be made. Thereby, the deformation | transformation to the 2nd side surface side of insert components can be prevented.

  The insert molding method according to claim 5 is characterized in that the filling speed of the resin is increased during the molding.

  According to this configuration, since the resin filling speed is increased during molding, it is possible to prevent the resin filled in the mold from partially lowering in temperature and solidifying. For this reason, the pressure applied to the first side surface and the second side surface can be made substantially equal, so that deformation of the insert part can be prevented.

  The insert molding apparatus according to the invention described in claim 6 is an insert molding apparatus in which an insert part is placed in a molding die, and the insert part is embedded in the resin by injecting the resin from the gate and molding the insert part. For example, in the insert molding apparatus 20) of the embodiment, the resin is formed between the first side surface of the insert part disposed on the gate side and the second side surface of the insert part disposed on the opposite side of the gate. The pressure difference adjusting means for setting the pressure difference in a predetermined range is provided.

According to this configuration, the pressure difference adjusting means is provided for setting the resin pressure difference within a predetermined range between the first side surface disposed on the gate side and the second side surface disposed on the opposite side of the gate. Therefore, the pressure difference between the both side surfaces of the insert part can be set to a small range, and deformation of the insert part can be prevented. Therefore, it is possible to prevent the insert part from being deformed into an unexpected shape during insert molding. Moreover, it can prevent that the insert components embed | buried in resin are exposed outside by the pressure difference at the time of insert molding. Further, the pressure between both side surfaces of the insert part may be adjusted, and foreign matter such as a chip is not generated by contact of the insert part, the mold, the pin, or the like.
Therefore, it is possible to provide an insert molding apparatus that can prevent the insert parts from being deformed and prevent foreign matters from being mixed therein.

  According to the insert molding method and the insert molding apparatus of the present invention, it is possible to prevent the insert parts from being deformed and to prevent foreign matters from being mixed therein.

It is a perspective view which shows the insert molded product in embodiment. The shaping | molding die in the insert molding apparatus of embodiment is shown, (a) is a schematic longitudinal cross-sectional view, (b) is a top view of the insert molding apparatus when it permeate | transmits an upper mold | type. The shaping | molding die in the insert molding apparatus of embodiment is shown, and it is III-III sectional drawing of FIG. It is a fragmentary perspective view which shows the flow area | region of the resin in the shaping | molding die in the insert molding apparatus of a modification.

Embodiments of the present invention will be described below with reference to the drawings.
(Insert molded product)
FIG. 1 is a perspective view showing an insert-molded product in the embodiment.
In the insert molded product 10 of this embodiment, a plurality of insert parts 11 made of a long material are arranged in parallel and integrated by a resin 13.
The insert molded product 10 is a conductive member, and each insert component 11 is made of a conductive material such as copper. Each insert component 11 is covered with an insulating resin 13 on the entire side surface. Adjacent insert parts 11 are shielded by an insulating resin 13. Both end portions 11a and 11a of each insert part 11 are exposed so as to be connectable to other conductive members.

(Insert molding equipment)
2A is a schematic longitudinal sectional view showing a mold in the insert molding apparatus, FIG. 2B is a plan view of the insert molding apparatus when seen through the upper mold, and FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 2.
As shown in FIGS. 2 and 3, the insert molding apparatus 20 has a molding die 21 including an upper die 22 and a lower die 23 that can be opened and closed by a dividing surface 24. The upper mold 22 and the lower mold 23 are provided with a cavity 25 that can be opened and closed by a dividing surface 24.
Support portions 26 that support both ends of each insert part 11 are provided on both ends in the longitudinal direction of the mold 21. Each insert component 11 is clamped in a state where it is supported by the support portion 26, so that the intermediate portion is arranged to float in the cavity 25, and the side peripheral surface is exposed in the cavity 25.

The molding die 21 is connected to a resin supply machine (not shown) having a configuration capable of supplying the molten and pressurized resin 13 while adjusting the supply speed.
In the cavity 25 of the molding die 21, a plurality of gates 27 made of pin gates are opened in the middle portion in the longitudinal direction. Each gate 27 is configured such that the resin 13 branched from the resin feeder is supplied from the flow path 28 of the upper mold 22.

  Each gate 27 is opened in a direction intersecting with the periphery of the plurality of insert parts 11. The plurality of gates 27 are provided on the mold surface 29 facing the first side surface 12 a of the plurality of insert parts 11. Moreover, the side gate 37 (refer FIG. 3) is provided in the division surface, and is opened in the width direction of the insert molded product 10. FIG.

The mold 21 of this embodiment is provided with a pressure difference adjusting means.
The pressure difference adjusting means is a means for adjusting the difference between the pressure of the resin 13 on the first side surface 12a side of the insert molded product 10 and the pressure of the resin 13 on the second side surface 12b side. The pressure difference adjusting means determines a pressure difference between the pressure applied from the resin 13 supplied to the cavity 25 to the first side surface 12a of the insert-molded product 10 and the pressure applied from the resin 13 to the second side surface 12b. It is a means to adjust to the range.

As shown in FIG. 3, the pressure of the molten resin 13 supplied into the cavity acts strongly on the first side surface 12a disposed on the gate 27 side.
The pressure of the resin 13 that wraps around the back side of the insert part 11 acts on the second side surface 12b disposed on the side opposite to the gate 27. Specifically, the molten resin 13 supplied into the cavity flows between the plurality of insert parts 11 and flows toward the mold surface 29 facing the second side surface 12 b, and moves along the mold surface 29. The pressure of the resin 13 that has reached the second side surface 12b acts.
Therefore, the pressure difference between the pressure applied to the first side surface 12a and the pressure applied to the second side surface 12b varies depending on various conditions of the molding die 21 from the start of molding to the middle of molding. When the pressure difference between the pressure applied to the first side surface 12a and the pressure applied to the second side surface 12b is small, the insert component 11 can be prevented from being deformed during molding, and the shape and position can be maintained.

As the pressure difference adjusting means, for example, adjustment of the filling speed of the resin 13, adjustment of the temperature of the mold surface 29 around the insert part 11, setting of the position of the gate 27, setting of the size of the gate 27, The structure etc. which can set the position of the insert component 11 can be mentioned.
In the insert molding apparatus 20 of the present embodiment, a supply amount of the molten resin 13 which is heated and pressurized by a resin supply machine (not shown) is adjusted. The supply amount per unit time is adjusted during molding. The insert molding device 20 has an adjustment mechanism that adjusts the filling speed of the resin 13. Further, a heater 31 for heating the mold surface 29 on the second side surface 12 b side is embedded in the lower mold 23 in the vicinity of the mold surface 29. The insert molding device 20 adjusts the temperature of the mold surface 29 by heating the mold surface 29 on the second side surface 12 b side with the heater 31 to raise the temperature.

Further, in the insert molding apparatus 20 of the present embodiment, the plurality of gates 27 are respectively disposed between the adjacent insert components 11 supported by the molding die 21. All the gates 27 are arranged between the adjacent insert parts 11.
By setting the position of the gate 27 between the insert parts 11, the resin 13 from each gate 27 does not directly collide with the first side surface 12 a of each insert part 11. Therefore, the insert molding device 20 can reduce the pressure applied from the resin 13 to the first side surface 12a.
In addition, by setting the position of the gate 27 between the insert parts 11, the resin 13 easily flows through the plurality of insert parts 11 to the mold surface 29 side facing the second side face 12b. Therefore, the insert molding device 20 can increase the flow amount of the resin 13 between the second side surface 12b and the opposite mold surface 29.

  Further, in the insert molding device 20, the diameters of the plurality of gates 27 may be different from each other. Specifically, the diameters are made different according to the filling volume of the resin 13 discharged from each gate 27 and filled into the cavity 25. The gate 27 with a large filling volume has a large diameter, and the gate 27 with a small filling volume has a small diameter. By setting the size of the gate 27, the flow state of the resin 13 can be easily made uniform.

Moreover, in the insert molding apparatus 20 of this embodiment, the position of the insert part 11 in the molding die 21 is set. Specifically, the distance between the mold surface 29 with the largest number of gates 27 and the first side surface 12a of the insert part 11 is the distance between the second side surface 12b and the mold surface 29 facing the second side surface 12b. Smaller than that.
By adjusting the initial position of the insert part 11 closer to the gate 27, the interval between the second side surface 12b and the mold surface 29 facing the second side surface 12b is widened, and the resin 13 can be easily flowed.

(Insert molding method)
A method for manufacturing the insert molded product 10 using the insert molding apparatus 20 having the above structure will be described.
Each condition is preset for each pressure difference adjusting means as described above.
For example, the insert part 11 is mounted on the support portion 26 in the mold 21 and the mold is clamped, and pressures at a plurality of positions around the insert part 11 are grasped in advance.
The pressure at a plurality of positions grasped in advance includes the pressure applied to the first side surface 12a of the insert part 11 by the flowing resin 13 when the heated and pressurized resin is supplied to the mold 21, and the flow Pressure applied to the second side surface 12b by the resin 13 to be included.

  In the present embodiment, the pressure difference between the pressure applied from the resin 13 supplied to the cavity 25 to the first side surface 12a of the insert molded product 10 and the pressure applied from the resin 13 to the second side surface 12b is substantially the same. The conditions of the pressure difference adjusting means are determined so that For example, the condition of the pressure difference adjusting means is determined by repeating a plurality of tests and simulations with the aim of keeping the pressure difference within 0.5 MPa in consideration of the entire load pressure. Thus, injection is performed with a pressure difference within a predetermined range.

  As the conditions of the pressure difference adjusting means, as described above, the temperature adjustment condition of the mold surface 29, the setting condition of the position of the insert part 11, the setting condition of the position of the gate 27, the setting condition of the size of the gate 27, the condition of the resin 13 The conditions for adjusting the filling speed are included.

  Regarding the temperature adjustment condition of the mold surface 29, the mold surface 29 is heated by the heater 31 to raise the temperature. In the present embodiment, the mold surface 29 on the second side surface 12b side is heated to be approximately the same as the temperature of the mold surface 29 on the first side surface 12a side or the temperature of the molten resin 13 supplied from the resin feeder. Heat to

  Regarding the position condition of the insert part 11, the distance between the mold surface 29 provided with the largest number of gates 27 and the first side surface 12a of the insert part 11 is determined by the mold surface facing the second side surface 12b and the second side surface 12b. It is made smaller than the interval with 29. By adjusting the initial position of the insert part 11 closer to the gate 27, the space between the second side surface 12b and the mold surface 29 facing the second side surface 12b is widened, and the fluidity of the resin 13 is improved.

  As a condition of the position of the gate 27, the openings of the plurality of gates 27 are respectively arranged between the adjacent insert parts 11 supported in the mold 21. The resin 13 from each gate 27 does not directly collide with the first side surface 12 a of each insert part 11. Therefore, the pressure applied from the resin 13 to the first side surface 12a can be reduced. In addition, the resin 13 from each gate 27 easily passes through the plurality of insert parts 11 and flows toward the mold surface 29 facing the second side surface 12b.

  As a size condition of the gate 27, the insert molding device 20 may make the diameters of the plurality of gates 27 different from each other. As described above, the gate 27 with a large filling volume has a large diameter, and the gate 27 with a small filling volume has a small diameter. By setting the size of the gate 27, the flow state of the resin 13 can be easily made uniform.

  As a condition for the resin filling speed, the supply amount of the molten resin 13 which is heated and pressurized by a resin feeder (not shown) is adjusted. The resin filling speed is increased by adjusting the supply amount of the resin 13 per unit time during the molding.

Using each determined condition, the pressure difference adjusting means is appropriately set, and the insert molding apparatus 20 including the molding die 21 is prepared.
Thereafter, the insert part 11 is placed in the molding die 21, the molten resin 13 heated and pressurized is supplied from a resin feeder, and injection is started from each gate 27 to start molding.
The pressure difference of the resin 13 is substantially the same between the first side surface 12a of the insert part 11 disposed on the gate 27 side and the second side surface 12b of the insert part 11 disposed on the side opposite to the gate 27. Thus, the resin 13 is injected with the pressure difference within a predetermined range.
And by filling resin 13 in the whole cavity, the whole side peripheral surface except the both ends of insert component 11 is embed | buried in resin 13, and shaping | molding is complete | finished.

(Function and effect)
According to the insert molding apparatus 20 and the insert molding method as described above, the resin 13 can be formed between the first side surface 12a disposed on the gate 27 side and the second side surface 12b disposed on the opposite side of the gate 27. Since the resin 13 is injected so that the pressure difference falls within a predetermined range, the pressure difference between the side surfaces 12a and 12b of the insert part 11 can be set to a small range, and deformation of the insert part 11 can be prevented. Therefore, it is possible to prevent the insert part 11 from being deformed into an unexpected shape during insert molding. Further, it is only necessary to adjust the pressure between the both side surfaces 12a and 12b of the insert part 11, and foreign matter such as a chip is not generated by the contact of the insert part 11, the molding die, the pin, or the like.
Therefore, it is possible to provide an insert molding method, an insert molding apparatus 20 and an insert molding method that can prevent deformation of the insert part 11 and prevent foreign matters from being mixed.

  Further, when the insert molded product 10 is used as a conductive member, the conductive member can be embedded in the resin 13 without being exposed, and a sufficient insulating property can be easily secured by not dispersing the pieces of the conductive member in the resin 13. be able to.

  Further, according to the present embodiment, the filling speed of the resin 13, the temperature of the mold surface 29, the position of the gate 27, the size of the gate 27, so as to maintain the pressure at a plurality of points in a substantially uniform state, Since the molding is performed using any one of the conditions of the insert part 11, the insert part 11 can be prevented from being deformed and the insert part 11 can be disposed at a desired position in the resin 13, and foreign matter is mixed in. Can be prevented.

In addition, according to the present embodiment, the mold surface 29 on the second side surface 12b side of the mold 21 is heated by the heater 31 to adjust the mold surface 29 temperature, so that the molten resin 13 becomes the mold on the second side surface 12b side. When contacting the surface 29, the temperature of the resin 13 does not drop suddenly and the viscosity does not rise suddenly.
Therefore, the resin 13 flows on the second side surface 12b side as well as the first side surface 12a side, and the pressure applied from the resin 13 to the first side surface 12a of the insert part 11 and the pressure applied to the second side surface 12b. Can be made comparable. Therefore, deformation of the insert part 11 toward the first side surface 12a and the second side surface 12b can be prevented.

  Moreover, according to this embodiment, the space | interval of the type | mold surface 29 in which the gate 27 was provided most and the 1st side surface 12a of the insert component 11 opposes the 2nd side surface 12b and the 2nd side surface 12b of the insert component 11. Since the initial position is adjusted so as to be smaller than the distance from the mold surface 29, the molten resin 13 can be actively flowed in the distance between the second side surface 12b and the mold surface 29 facing the second side surface 12b. The pressure applied to the two side surfaces 12b can be increased to be equal to that of the first side surface 12a. Thereby, the deformation | transformation to the 2nd side surface 12b side of the insert component 11 can be prevented.

  Moreover, according to this embodiment, since the resin filling speed is increased during molding, it is possible to prevent the resin 13 filled in the mold 21 from partially lowering in temperature and solidifying. For this reason, the pressure applied to the first side surface 12a and the second side surface 12b can be made substantially equal, so that the deformation of the insert part 11 can be prevented.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

In the said embodiment, the example which does not provide the gate in the type | mold surface 29 facing the 2nd side surface 12b of the insert component 11 was demonstrated. However, a gate may be provided also on the mold surface 29 facing the second side surface 12b. In that case, the pressure received by the first side surface 12a by the injection resin 13 is greater than the pressure received by the second side surface 12b, such as by providing fewer gates than the gate provided on the mold surface 29 facing the first side surface 12a. It is good to do.
Furthermore, as shown in FIG. 4, it is possible to provide all the gates 27 on the mold surface 29 facing the first side surface 12 a of the insert molded product 10.

  In addition, it is possible to appropriately replace the components in the above-described embodiments with known components without departing from the spirit of the present invention.

11 Insert component 12a First side surface 12b Second side surface 13 Resin 20 Insert molding device 21 Mold 27 Gate 29 Mold surface 31 Heater

Claims (6)

In the insert molding method of burying the insert part in the resin by placing the insert part in the mold and injecting and molding the resin from the gate,
The pressure difference of the resin is within a predetermined range between the first side surface of the insert part disposed on the gate side and the second side surface of the insert part disposed on the opposite side of the gate. An insert molding method characterized by injecting a resin. In order to maintain the pressure at a plurality of points set around the insert part in a substantially uniform state, the filling speed of the resin, the temperature of the mold surface around the insert part, the position of the gate, Determining at least one condition of the size of the gate and the position of the insert part;
The insert molding method according to claim 1, wherein molding is performed using the determined conditions.   The insert molding method according to claim 2, wherein the temperature of the mold surface around the insert part is adjusted by heating with a heater provided on the second side surface of the mold.   The insert is arranged such that the distance between the mold surface having the largest number of gates and the first side surface of the insert part is smaller than the distance between the second side surface and the mold surface facing the second side surface. 4. The insert molding method according to claim 2, wherein an initial position of the part is adjusted.   The insert molding method according to any one of claims 2 to 4, wherein a filling speed of the resin is increased during molding. In an insert molding apparatus in which an insert part is placed in a molding die, and the insert part is embedded in the resin by injecting resin from a gate and then molding,
Pressure difference adjustment that makes the pressure difference of the resin a predetermined range between the first side surface of the insert part disposed on the gate side and the second side surface of the insert part disposed on the opposite side of the gate An insert molding apparatus comprising means.

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