JP5128892B2 - Insert core positioning mechanism - Google Patents

Description

  The present invention relates to an insert core positioning mechanism for positioning a insert core at a predetermined position in a cavity of a mold when a cylindrical insert core is coated with a synthetic resin and molded.

  For example, the component shown in FIG. 6 shows a toroidal core 1 of a toroidal coil, and this toroidal core 1 is formed by coating a cylindrical insert core 2 made of a magnetic material with a coating layer 3 made of a synthetic resin. Has been. The toroidal core 1 has a coil 4 wound in the axial direction between the inside and outside of the toroidal core 1 to complete a part.

  The toroidal core 1 is formed by forming the coating layer 3 by disposing the insert core 2 in the mold cavity and injecting a resin material into the mold with an injection device. At this time, if the insert core 2 is not in a predetermined position, the thickness of the coating layer 3 is not constant. Therefore, the insert core 2 is positioned so as to be positioned in the cavity. There is a need.

  In this type of conventional positioning mechanism, positioning is performed by bringing a positioning member into contact with the outer peripheral surface of the insert core 2. FIG. 5 shows an outline of a conventional positioning mechanism, in which the movable mold 5a slides with respect to the fixed mold 5b in the direction indicated by the arrow P perpendicular to the axis of the insert core 2. The mold is opened and closed. These molds 5a and 5b are provided with positioning support pins 6 that protrude and appear in a cavity 5c in which the insert core 2 is disposed. In FIG. 5, the positioning support pins 6 of the fixed mold 5b are omitted. That is, when each of the four positioning support pins 6 protrudes into the cavity 5c with the insert core 2 set in the cavity 5c, the tips of the positioning support pins 6 come into contact with the insert core 2. The insert core 2 is supported and positioned at a predetermined position in the cavity 5c, for example, at a central portion in the cavity 5c. If the resin material is injected into the cavity 5c in this state, the insert core 2 is covered with the resin material, and the coating layer 3 is formed.

  However, in the conventional insert core positioning mechanism described above, since the positioning is based on the outer diameter of the insert core, the following problems may occur.

  Since the positioning support pins 6 are positioned in contact with the outer peripheral surface of the insert core 2, the insert core 2 is likely to be displaced in the cavity 5c. For this reason, even if a positional deviation occurs, the coating layer 3 is formed with a sufficient thickness so that the insert core 2 is reliably covered with the resin material, thereby reducing molding defects. I am trying. In addition, as described above, since it is necessary to slide the mold in the direction perpendicular to the axis of the insert core 2, the structure may be complicated.

  In view of this, in the present invention, the position of the cylindrical insert core in the cavity is positioned with reference to the inner diameter of the insert core, thereby suppressing the displacement of the insert core and unnecessarily thickening the coating layer of the resin material. An object of the present invention is to provide an insert core positioning mechanism that eliminates the need for molding.

As a technical means for achieving the above object, the insert core positioning mechanism according to the present invention is configured such that a cylindrical insert core is positioned at a predetermined position in the cavity, and a resin material is injected into the cavity. When molding a molded article in which the insert core is coated with a resin material, the insert core positioning mechanism for positioning the insert core at a predetermined position in the cavity moves in the radial direction of the insert core disposed in the cavity. Three positioning inside pins that are positioned at the pressing position and hold the insert core by pressing the inner peripheral surface of the insert core; a moving member that moves inside the insert core in the axial direction of the insert core; While guiding the radial movement of the positioning inside pin, the axial direction of the insert core An inner pin guide means for preventing movement of the inner pin, and the moving member has a side surface that is a regular triangular frustum-shaped inclined surface formed on a part of the moving member, and the proximal end portion of the positioning inner pin An inside pin pressing portion that individually contacts each other, and an inside pin holding portion that regulates a part of the positioning inside pin and maintains the base end portion in contact with the inside pin pressing portion, in a state where we arranged an insert core into the cavity, the extruding said positioning inside pins inside the pin pressing part until the pressing position by moving the moving member, the insert by pressing the inner circumferential surface of said insert core It is characterized by positioning in the cavity of the core.

  When the inside pin moving means is operated in a state where the insert core is disposed in the cavity, the positioning inside pin moves to the pressing position in the radial direction of the insert core. For this reason, an insert core will be in the state by which the inner peripheral surface was pressed with the positioning inside pin, and an insert core will be positioned in the predetermined position, for example, the center position in a cavity. At this time, the insert core can be positioned in a stable state if the three inside pins for positioning press the equally spaced positions on the inner peripheral surface of the insert core.

Further, the axial movement of the insert core of the moving member, the positioning inside the pin is obtained so as to move between a spaced position and the pressing position.

  The positioning inside pin is maintained in contact with the inside pin pressing portion by the inside holding portion, and movement of the insert core in the axial direction is prevented by the inside pin guide means. For this reason, the positioning inside pin whose base end portion is in contact with the inside pin pressing portion formed by the inclined surface of the side surface of the regular triangular frustum shape changes the contact position with respect to the inclined surface by the movement of the moving member. . In response to the change of the contact position, the positioning inside pin moves in the radial direction of the insert core. And it is pressed by the inner peripheral surface of an insert core by moving toward the outer side of radial direction.

According to a second aspect of the present invention, there is provided the insert core positioning mechanism comprising: a bush member in which the insert pin guide means is positioned in a cavity and the insert core is loosely fitted; and a guide hole formed in a peripheral wall of the bush member. constituted by a, the loosely inserted the tip portion of the positioning inside pin into the guide hole, and a tip portion characterized in that the retractable from said guide hole to the outer peripheral portion of the bush member.

  When the insert core is disposed in the cavity, it is loosely fitted to the bush member. The positioning inside pin is loosely inserted into the guide hole formed in the bush member. For this reason, the positioning inside pin moves in the radial direction of the insert core within the guide hole. When moving toward the outside in the radial direction, the tip of the positioning inside pin protrudes outside the guide hole and presses the inner surface of the insert core.

The insert core positioning mechanism according to the invention of claim 3 is characterized in that the moving member moves in the axial direction with respect to the insert core by an opening / closing operation of a mold forming the cavity .

  For the movement of the moving member, it is possible to employ a mechanism that moves the insert core with respect to the insert core using a driving force of a motor or the like with the insert core disposed in the cavity. It is intended to move using the action. Since the opening / closing operation of the mold is performed by moving the mold, the moving member is moved relative to the insert core in the mold by using the movement of the mold.

  According to the positioning mechanism of the insert core according to the present invention, since the positioning of the cylindrical insert core in the cavity is performed with reference to the inner diameter of the insert core, the predetermined position can be stably maintained. Moreover, the mold dividing surface is not parallel to the surface including the axis of the insert core as in the prior art, but is a surface perpendicular to the axis. As in the conventional case, when the surface is parallel to the surface including the shaft, positioning is performed on the basis of the outer diameter of the insert core, and at least four support pins for positioning are required. On the other hand, in the positioning mechanism according to the present invention, the positioning inside pin can be pressed against the inner peripheral surface of the insert core, and at least three positioning inside pins may be used. In addition, the insert core can be reliably positioned with a simple structure, rather than a structure in which the mold is slid in the radial direction of the insert core. For this reason, it is not necessary to make room for the thickness of the coating layer made of the resin material covering the insert core, and the yield of the molded product can be improved. In addition, by reducing the thickness of the coating layer, the total extension of the coil wound when the toroidal core is formed is shortened, and the amount of coils to be used can be reduced.

  Further, since the positioning inside pin can be moved by the movement of the moving member arranged inside the cylindrical insert core, the positioning inside pin can be moved reliably with a simple structure.

  Further, the movement of the moving member can be reliably converted into the movement of the positioning inside pin with a simple structure.

According to the insert core positioning mechanism of the second aspect of the present invention, the positioning inside pin is loosely inserted into the guide hole of the bush member so that it is in a fixed position with respect to the bush member. Yes. Therefore, by moving the moving member relative to the bush member, the positioning inside pin can be reliably moved in the radial direction of the insert core.

According to the insert core positioning mechanism according to the invention of claim 3 , the positioning inside pin is moved in conjunction with the opening / closing operation of the mold, so that a separate drive source is not required, and the structure is simplified. It can be operated reliably, and the insert core can be reliably maintained in a predetermined position.

  The insert core positioning mechanism according to the present invention will be specifically described below based on the preferred embodiments shown in the drawings.

FIG. 1 is a schematic perspective view showing the structure of the main part of an insert core positioning mechanism according to the present invention. This positioning mechanism mainly includes a bush member 11 which is an inside pin guide means provided with a cylindrical guide bush 11a, and an inside pin guide 12 which constitutes a moving member which is slidable in the axial direction inside the bush member 11. The inside pin guide 12 includes three positioning inside pins 13 that move in the radial direction of the bush member 11 with respect to the guide bush 11a.

  The bush member 11 includes a cylindrical guide bush 11a, a flange portion 11b formed at one end portion of the guide bush 11a, and a guide hole 11c into which the distal end portion of the positioning inside pin 13 is loosely inserted. As shown in FIG. 4, the positioning inside pin 13 is formed in a substantially convex shape in plan view, and a small pin portion 13a at the tip is loosely inserted into the guide hole 11c. A large flange portion 13b at the proximal end is connected to the inside pin guide 12.

The inside pin guide 12 has a long bar shape, and a pin guide portion 12a is formed at the tip. The pin guide portion 12a has a center portion formed in a regular triangular frustum shape, and a side surface formed by the inclined surface of the regular triangular frustum shape serves as an inside pin pressing portion 12b. An inside pin holding portion 12c is formed facing the side of the regular triangular frustum. As shown in FIGS. 1 and 4, the inside pin holding portion 12 c has an end surface of the inside pin holding portion 12 c that faces the side, and is formed in a substantially W shape. The ridgelines of the mountain face each other while maintaining a state parallel to the sides of the regular triangular frustum. Further, the flange portion 13b of the positioning inside pin 13 is located in a space formed by the central peak of the W shape and the side wing portion, and the adjacent inside pin holding portion 12c The flange portion 13b of the positioning inside pin 13 adjacent to each space portion is positioned , and the positioning inside pin 13 is regulated by the inside pin holding portion 12c and the inside pin pressing portion 12b. Each of the W-shaped surfaces of the inside pin holding portion 12c facing the space and the peripheral surface of the flange portion 13b of the positioning inside pin 13 are formed in parallel with the side surfaces of the regular triangular frustum shape.

  2 and 3 show a state in which the positioning mechanism is incorporated in a mold clamping device. FIG. 2 shows when the mold is opened, and FIG. 3 shows when the mold is clamped. As shown in FIG. 2, the guide bush 11 a of the bush member 11 is positioned in the lower mold cavity portion 22 of the lower mold 21, and the flange portion 11 b is accommodated in a recess 23 formed on the lower surface of the lower mold 21. Thus, the bush member 11 is integrated with the lower mold 21.

  The inside pin guide 12 has a distal end located inside the bush member 11. The inside pin guide 12 passes through the lower plate 25 to which the lower mold 21 is attached and is fixed to the backup plate 26. The backup plate 26 and the lower plate 25 can be brought into contact with and separated from each other, and a restoring force such as a spring (not shown) is urged so that the lower plate 25 moves in a direction away from the backup plate 26.

  In the pin guide portion 12a of the inside pin guide 12, the end surface of the flange portion 13b of the positioning inside pin 13 is brought into contact with the inside pin pressing portion 12b, and the flange portion 13b is connected to the inside pin holding portion 12c. It is. Further, the tip of the pin portion 13a of the positioning inside pin 13 is loosely inserted into the guide hole 11c of the bush member. Therefore, the positioning inside pin 13 is constrained by the bush member 11 and is positioned at a fixed position in the lower mold cavity portion 22.

As shown in FIG. 3 at the time of mold clamping, the upper mold 32 attached to the upper plate 31 and the lower mold 21 are in close contact with each other, and the upper mold cavity 33 and the lower mold cavity 22 of the upper mold 32 cooperate. In operation, a cavity for the molded product is formed. The tip portion of the inside pin guide 12 is projected from the lower die 21 so as to be positioned in the upper die cavity portion 33 when the die is clamped.

  Further, an appropriate number of support pins 35 are arranged so as to protrude into the lower mold cavity portion 22 from the bottom surface of the lower mold cavity portion 22, and in the direction parallel to the mold opening / closing direction in the lower mold cavity portion 22. A slidable ejector pin 36 is provided.

  The operation of the insert core positioning mechanism according to the present invention configured as described above will be described below. In this embodiment, the case where the toroidal core 1 of the toroidal coil shown in FIG. 6 is formed will be described, and the case where a magnetic metal is used as the insert core 2 will be described.

  As shown in FIG. 2, the insert core 2 is disposed in the lower mold cavity portion 22 when the mold is opened. At this time, the insert core 2 is loosely fitted into the bush member 11 disposed in the lower mold cavity portion 22. Further, the insert core 2 is supported by the support pins 35 in a state of floating from the bottom surface in the cavity portion 22. In this state, the mold clamping operation is performed.

The mold clamping operation is performed by the operation of a mold clamping mechanism such as a hydraulic cylinder (not shown) to push the backup plate 26 toward the upper mold 32. When the backup plate 26 is pushed up, the lower plate 25 is pushed up via the spring (not shown) or the like and rises. When the lower plate 25 rises and comes into close contact with the upper plate 31, the lower plate 25 stops at the position. In this state, the backup plate 26 is further pushed up against the restoring force of the spring by the operation of the mold clamping mechanism. Since the inside pin guide 12 is attached to the backup plate 26, the inside pin guide 12 slides and rises with respect to the bush member 11. The inside pin guide 12 is formed with an inside pin pressing portion 12b formed of a side surface of a regular triangular frustum at the tip portion, and the flange portion 13b of each of the three positioning inside pins 13 is formed on each inside pin pressing portion 12b. The back of the is in contact. Further, the front surface of the flange portion 13b is regulated by the inside pin holding portion 12c, and the distal end portion of the positioning inside pin 13 is loosely inserted into the guide hole 11c formed in the guide bush 11a of the bush member 11. ing. For this reason, as the inside pin guide 12 rises, the positioning inside pin 13 moves forward and moves forward in the radial direction of the guide bush 11a by the inside pin pressing portion 12b formed by the inclined surface, and the tip of the pin portion 13b Protrudes from the guide hole 11c of the guide bush 11a. Since the insert core 2 is loosely fitted to the guide bush 11a, the tip of the pin portion 13a of the positioning inside pin 13 protruding from the guide hole 11c presses the inner peripheral surface of the insert core 2. . Moreover, since the positioning inside pin 13 is restrained by the inside pin pressing portion 12b, the insert core 2 is reliably pressed by the positioning inside pin 13. Further, since this positioning inside pin 13 presses the inner peripheral surface of the insert core 2 in three directions, the insert core 2 is reliably positioned at a predetermined position.

  The positioning inside pin 13 reliably positions the insert core 2 while the backup plate 26 is in contact with the lower plate 25. In this state, a gap is formed between the insert core 2 and the wall surface of the cavity portion. By injecting the resin material into the cavity portion by an injection device (not shown), the resin material is placed in the gap. A film layer 3 that fills and covers the insert core 2 is formed.

  Then, when the back-up plate 26 is lowered by operating the mold clamping device after the resin material is cured, the inside pin 13 for positioning is pushed by the inside pin holding portion 12c as the inside pin guide 12 is lowered. The guide bush 11a moves backward in the radial direction. Thereby, the restraint of the insert core 2 is released. Further, when the backup plate 26 is lowered, the lower plate 25 is also lowered to perform mold opening. Next, when the protruding pin 36 is raised in the lower mold cavity portion 22, the toroidal core 1 as a molded product is taken out.

  On the inner peripheral surface of the completed toroidal core 1, as shown in FIG. 6, insert support holes 2 a are formed at three locations where the tip of the positioning inside pin 13 is pressed. Further, a support hole 2b supported by the support pin 35 is formed on the bottom surface, and a support hole 2c is formed on the top surface by a support pin (not shown) that protrudes from the upper mold cavity portion 33 and abuts against the top surface of the insert core 2. . In the lower mold cavity portion 22, the insert core 2 is supported by the four support pins 35 so as to maintain the posture, so that four support holes 2b are formed, whereas in the upper mold cavity portion 33, In order to prevent the insert core 2 from being inadvertently raised in the cavity portion, it is pressed by two support pins to form two support holes 2c.

  In the embodiment described above, since the case where the core is used for the core of the toroidal coil has been described, the insert core has been described as a metal having magnetism. However, if the cylindrical insert core is used, a non-magnetic material is used depending on the application. It can also be used for insert cores of other metals.

  According to the insert core positioning mechanism according to the present invention, the cylindrical insert core can be reliably positioned at a predetermined position in the cavity, and the structure is simple, and the positioning mechanism is linked to the opening / closing operation of the mold. Since it can be driven, it contributes to labor saving of the injection molding machine.

It is a schematic perspective view explaining the structure of the principal part of the positioning mechanism of the insert core which concerns on this invention, (a) has shown the state at the time of a mold opening, (b) has each shown the state at the time of mold clamping. It is a figure which shows the metal mold | die provided with the positioning mechanism of the insert core which concerns on this invention, and has shown the state at the time of mold opening. It is a figure which shows the metal mold | die provided with the positioning mechanism of the insert core which concerns on this invention, and has shown the state at the time of mold clamping. It is a top view of the principal part of the positioning mechanism of the insert core which concerns on this invention. It is a figure explaining the conventional positioning mechanism, and has positioned the cylindrical insert core on the basis of an outside diameter. It is a figure which shows an example of the molded article suitable for positioning with the positioning mechanism which concerns on this invention, (a) is a top view, (b) is a front view, and shows the state which wound the coil in part (C) is a bottom view.

Explanation of symbols

1 Toroidal core 2 Insert core 3 Coating layer 4 Coil
11 Bushing member
11a Guide bush
11c Guide hole
12 Inside pin guide
12a Pin guide
12b Inside pin pressing part
12c Inside pin holder
13 Inside pin for positioning
13a Pin part
13b Flange
21 Lower mold
22 Lower mold cavity
25 Lower plate
26 Backup plate
31 Upper plate
32 Upper mold
33 Upper mold cavity
35 Support pin

Claims (3)

When a cylindrical insert core is positioned at a predetermined position in the cavity and a resin material is injected into the cavity to form a molded article in which the insert core is coated with the resin material, the insert core is placed in the cavity. In the insert core positioning mechanism for positioning at a predetermined position,
Three positioning inside pins that move in the radial direction of the insert core disposed in the cavity and are positioned at the pressing position, press the inner peripheral surface of the insert core and hold the insert core,
A moving member that moves inside the insert core in the axial direction of the insert core;
The inside pin guide means for guiding the movement of the positioning inside pin in the radial direction and blocking the movement of the insert core in the axial direction,
The moving member includes a side surface that is a regular triangular frustum-shaped inclined surface formed on a part of the moving member, and an inside pin pressing portion that individually contacts a base end portion of the positioning inside pin; and the positioning inside An inside pin holding part that regulates a part of the pin and maintains the base end part in contact with the inside pin pressing part,
In a state where we arranged an insert core into the cavity, the extruding said positioning inside pins inside the pin pressing part until the pressing position by moving the moving member, the insert by pressing the inner circumferential surface of said insert core An insert core positioning mechanism characterized by positioning in a cavity of a core.   The inside pin guide means includes a bush member that is located in the cavity and in which the insert core is loosely fitted, and a guide hole formed in a peripheral wall of the bush member,
  2. The insert core according to claim 1, wherein the distal end portion of the positioning inside pin is loosely inserted into the guide hole, and the distal end portion can be projected and retracted from the guide hole to the outer peripheral portion of the bush member. Positioning mechanism.   3. The insert core positioning mechanism according to claim 1, wherein the moving member moves in an axial direction with respect to the insert core by an opening / closing operation of a mold forming the cavity.

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