WO2018179028A1

WO2018179028A1 - Undercut treatment mechanism, molding die and molded article

Info

Publication number: WO2018179028A1
Application number: PCT/JP2017/012248
Authority: WO
Inventors: 正典反本
Original assignee: 株式会社テクノクラーツ
Priority date: 2017-03-27
Filing date: 2017-03-27
Publication date: 2018-10-04
Also published as: JPWO2018180824A1; JP6999959B2; WO2018180824A1

Abstract

The present invention provides: an undercut treatment mechanism which can be designed to have a compact and simple configuration while enabling easy stripping of an undercut part; a molding die; and a molded article. Provided is an undercut treatment mechanism 10 which is used by being mounted to a molding die 1 for molding a molded article P having an undercut part P1 and which enables stripping of an undercut part P1 that protrudes in a direction intersecting with the stripping direction of the molded article P, the undercut treatment mechanism being provided with: a holder 20 which is fixed to or integrally formed with the molding die 1; a slide piece 30 which has a molding part 32 for molding the undercut part P1 and which is capable of sliding with respect to the holder 20 so as to cause the molding part 32 to come off the undercut part P1; and a holding piece 50 which capable of sliding with respect to the holder 20 in a direction intersecting with the stripping direction of the molded article P and which slidably holds the slide piece 30.

Description

Undercut processing mechanism, mold for molding and molded product

The present invention relates to an undercut processing mechanism, a molding die, and a molded product that are attached to a molding die for molding a molded product having an undercut portion.

Many molding mechanisms for undercuts have been developed in the form of molds for molding molded products having undercuts. As an undercut processing mechanism, for example, a so-called loose core is generally used.

In addition, when molding a molded product that is difficult to mold with an undercut processing mechanism using a conventional loose core, for example, a molded product in which a boss having a hollow portion protrudes in a direction intersecting the die-cutting direction of the entire molded product, An undercut processing mechanism has already been proposed by the present applicant that makes it possible to easily punch a boss that is an undercut portion (see, for example, Patent Document 1).

The undercut processing mechanism described in Patent Document 1 includes a holder provided in a fixed mold or a movable mold of a molding die, and a molding core that molds an undercut portion, and the molding core includes a first core and a first core. It consists of two cores, and the first core and the second core have side surfaces that are inclined adjacent to each other, and are configured so that the undercut portion can be punched by sliding in the holder along the side surfaces.

JP 2010-155381 A

According to the undercut processing mechanism described in Patent Document 1, molding of a molded product having a shape difficult to be molded by the conventional undercut processing mechanism using a loose core is facilitated, and a support rod and a guide rod are not required. Therefore, it can be configured more compactly than an undercut processing mechanism using a conventional loose core.

The present invention realizes easy and compact molding of a molded product having an undercut portion like the undercut processing mechanism described in Patent Document 1 in a configuration different from the undercut processing mechanism described in Patent Document 1. A possible undercut processing mechanism, a molding die and a molded product are proposed.

An object of the present invention is to provide an undercut processing mechanism, a mold for molding, and a molded product that can be easily compacted while being compact and simple.

According to the present invention, the undercut portion which is attached to and used in a molding die for molding a molded product having an undercut portion and protrudes in a direction intersecting with the die cutting direction of the molded product can be die-cut. A cut processing mechanism having a holder fixed or integrally formed with the molding die and a molding part for molding the undercut part, and the molding part is separated from the undercut part. A sliding piece that is slidable with respect to the holder, and a holder that is slidable with respect to the holder in a direction that intersects with a die-cutting direction of the molded product, and that holds the sliding piece slidably. And the sliding piece is configured so that the molding part is detached from the undercut part by sliding the holding piece relative to the holder in conjunction with opening of the molding die. The holder It is undercut processing mechanism, characterized by being configured to slide against.

Further, in the undercut processing mechanism of the present invention, the holding piece is provided via an inclined member attached to the molding die so as to be inclined with respect to the mold opening and clamping directions of the molding die. It is configured to slide relative to the holder in conjunction with mold opening and clamping of the molding die.

In the undercut processing mechanism of the present invention, each of the holder and the holding piece restricts the moving direction of the sliding piece when the molding die is opened in a direction in which the molding part is separated from the undercut part. It is characterized by comprising a regulating means.

In the undercut processing mechanism of the present invention, the holder can store the sliding piece and / or the holding piece partially or completely.

Further, in the undercut processing mechanism of the present invention, the sliding piece is a molded member that molds the hollow portion or space portion of the undercut portion so that the molded product having a hollow portion or space portion in the undercut portion can be formed. It is characterized by having.

Further, the present invention is a molding die including the undercut processing mechanism.

Further, the present invention is a molded product molded by the undercut processing mechanism or the molding die.

According to the undercut processing mechanism and the molding die of the present invention, the sliding piece slides relative to the holder by the holding piece sliding relative to the holder in conjunction with the mold opening of the molding die. Since it moves away from the undercut portion, the undercut portion can be easily punched out while being compact and simple.

It is sectional drawing at the time of mold clamping of the metal mold | die 1 of 1st Embodiment of this invention. It is sectional drawing after the mold opening of the metal mold | die 1 of FIG. It is sectional drawing after the protrusion operation | movement of the molded article P of the molding die 1 of FIG. It is an enlarged view of the peripheral part of the undercut processing mechanism 10 in FIG. It is an enlarged view of the peripheral part of the undercut processing mechanism 10 in FIG. FIG. 2 is a perspective view of an undercut processing mechanism 10 of the molding die 1 of FIG. 1. It is a disassembled perspective view of the undercut process mechanism 10 of the metal mold | die 1 of FIG. It is a perspective view which shows an example of the molded product which can be shape | molded with the undercut process mechanism and molding die of this invention.

1 is a cross-sectional view of the molding die 1 according to the first embodiment of the present invention during clamping, FIG. 2 is a cross-sectional view of the molding die 1 of FIG. 1 after opening, and FIG. FIG. 2 is a cross-sectional view after a protruding operation of a molded product P of one molding die 1. 4 is an enlarged view of the peripheral portion of the undercut processing mechanism 10 in FIG. 1, and FIG. 5 is an enlarged view of the peripheral portion of the undercut processing mechanism 10 in FIG. 6 is a perspective view of the undercut processing mechanism 10 of the molding die 1 of FIG. 1, and FIG. 7 is an exploded perspective view of the undercut processing mechanism 10 of the molding die 1 of FIG. In FIGS. 1 to 6, only the holder 20 is shown in a sectional view of the undercut processing mechanism 10. In FIGS. 1 to 3, some of the reference numerals are omitted.

The molding die 1 according to the first embodiment of the present invention includes a fixed die 100 that injects a molding material and molds the outer surface side of a molded product P (see FIG. 1), and an inner surface including an undercut portion P1 of the molded product P. Although it is the same structure as the well-known injection mold provided with the movable mold | type 101 which shape | molds the side, it differs from a well-known injection mold in the point provided with the undercut process mechanism 10. FIG. For convenience, the description will be given with the fixed mold 100 side in FIG. 1 as the upper side and the movable mold 101 side as the lower side.

In the molding die 1 of the present embodiment, the fixed mold 100 includes a fixed side mounting plate 103, a fixed side mold plate 104, a locating ring 105, and a sprue bush 106, as in the known injection molding die, and a movable mold 101. Comprises a movable mounting plate 107, a movable mold plate 108, a spacer block 109, two ejector base plates 110, an ejector pin 111, a return pin 112, a spring 113, and an ejector rod 114. After the molding and mold opening, the ejector is When the base plate 110 moves in the direction in which the molded product P is removed (upward in FIG. 1) with respect to the movable side mold plate 108, the ejector pins 111 project the molded product P. In addition, since said component is the same as that of a well-known injection mold, description is abbreviate | omitted.

Further, in the molding die 1 of the present embodiment, an undercut processing mechanism 10 that enables the undercut portion P1 to be removed is incorporated in the movable mold 101, and a holding piece 50 of the undercut processing mechanism 10 described later. An angular pin 12 that is an inclined member that advances and retracts in conjunction with mold clamping and mold opening of the molding die 1 is tilted with respect to the mold clamping and mold opening direction (vertical direction in FIG. 1) of the molding die 1. In this way, it is fixed to the fixed side template 104.

The undercut processing mechanism 10 forms the undercut portion P1 when the molded product P is molded, and disengages from the undercut portion P1 when the molding die 1 is opened. The cut portion P1 can be removed from the molding die 1.

In the present embodiment, the undercut portion P1 is a cylindrical boss that protrudes from the inner surface side of the molded product P in a direction that intersects the die-cutting direction of the molded product P (upward direction in FIG. 1). In addition, the undercut part which can be shape | molded and die-cut in the undercut process mechanism of this invention, a metal mold | die, and a molded article is not limited to a cylindrical boss so that it may mention later. The material of the molded product P is not limited to a synthetic resin such as plastic, but may be a metal such as iron, copper, or aluminum.

The undercut processing mechanism 10 includes a holder 20 embedded and fixed in the movable side mold plate 108, a sliding piece 30 having a molding portion 32 for molding the undercut portion P1 of the molded product P, and the sliding piece 30. The holding piece 50 is slidably held, and the sliding piece 30 and the holding piece 50 slide relative to the holder 20 in conjunction with the mold opening and clamping of the molding die 1 via the angular pin 12. The molding portion 32 of the sliding piece 30 forms the undercut portion P1 when the molding die 1 is clamped, and the molding portion 32 of the sliding piece 30 is opened when the molding die 1 is opened. Operates so as to deviate from the undercut portion P1.

The holder 20 is embedded in the movable side template 108 of the movable mold 101, partially stores the sliding piece 30 and the holding piece 50, and regulates the moving direction of the sliding piece 30 and the holding piece 50. The holder 20 is a U-shaped member in plan view, and a slant groove 22 that is a restricting means for restricting the moving direction of the sliding piece 30 and a horizontal groove 24 that is a restricting means for restricting the moving direction of the holding piece 50. On both inner surfaces facing each other.

The slant groove 22 is slidably fitted with protrusions 44 of a sliding piece 30 to be described later, and the molding portion 32 of the sliding piece 30 moves in the moving direction of the sliding piece 30 when the molding die 1 is opened. It is inclined with respect to the mold opening direction of the molding die 1 so as to be regulated in a direction away from the undercut portion P1. Here, the direction in which the molding portion 32 of the sliding piece 30 is detached from the undercut portion P1 means that the molding portion 32 of the sliding piece 30 is detached from the undercut portion P1 without deforming and damaging the undercut portion P1. In this embodiment, the sliding piece 30 coincides with the central axis of the cylindrical boss (undercut portion P1) and moves away from the undercut portion P1.

The horizontal groove 24 is provided so that a first protrusion 52 of a holding piece 50, which will be described later, is slidably fitted, and the moving direction of the holding piece 50 is restricted in the horizontal direction (left-right direction in FIG. 1). . Note that the moving direction of the holding piece 50 is not limited to the horizontal direction, and instead of the horizontal groove 24, an inclined groove inclined with respect to the horizontal direction may be provided in the holder 20.

The shape of the holder 20 is not limited to a specific shape, and the sliding piece 30 and the holding piece 20 are held so that the molding portion 32 of the sliding piece 30 is detached from the undercut portion P1 when the molding die 1 is opened. It is only necessary that the moving direction of the piece 50 can be regulated. Furthermore, the holder 20 may be formed by being divided into a plurality of members, or may be formed integrally with the movable side template 108.

The sliding piece 30 includes a forming part 32 for forming the undercut part P1, a sliding part 36 that slides with respect to the holder 20 and the holding piece 50, and a shaft part 38 that connects the forming part 32 and the sliding part 36. And have. The forming portion 32, the pin 34, the sliding portion 36, and the shaft portion 38 may be integrally formed, and part or all of them are formed as one member so that the sliding piece 30 can be configured. It may be.

The forming part 32 is a trapezoidal block, has a hollow part 42 for forming the undercut part P1 on the upper surface 40, and has a pin 34 for forming the hollow part of the undercut part P1 in the hollow part 42. In the molding portion 32, the upper surface 40, the hollow portion 42, and the exposed surfaces of the pins 34 become a molding surface for molding a part of the molded product P and the undercut portion P1. For this reason, the molding part 32 is formed and arranged so that there is no gap between the upper surface 40 and the upper surface of the movable side mold plate 108 at the time of clamping, in order to prevent molding defects of the molded product P.

The pin 34 is a cylindrical shaped member that molds the hollow portion of the undercut portion P1. The pin 34 is disposed in the hollow portion 42 of the molding portion 32 so that the hollow portion of the undercut portion P1 can be molded, and is fixed to the molding portion 32 via a fixing shaft member 43.

The sliding portion 36 is a trapezoidal block, and is provided on a side surface in contact with the inner surface of the holder 20 where the oblique groove 22 is provided, and is provided on the lower surface and is provided on the lower surface and is provided on the lower surface. A dovetail groove 46 slidably engaged with the second ridge 54 of the holding piece 50 is provided.

The shaft portion 38 has a cylindrical shape and is erected from the lower surface of the molding portion 32. The shaft portion 38 is fixed to the upper surface of the sliding portion 36 by a bolt 48.

The shapes of the molded part 32, the pin 34, the sliding part 36, and the shaft part 38 are not limited to specific shapes, and may be changed as appropriate according to the shape of the molded product P.

The holding piece 50 is a trapezoidal block. The holding piece 50 is provided on the inclined surface and the first ridge 52 provided on the side surface in contact with the inner surface provided with the horizontal groove 24 of the holder 20 and slidably fitted in the horizontal groove 24. The dovetail groove 46 of the sliding piece 30 has a second protrusion 54 that is slidably engaged, and an inclined hole 56 that is drilled from the upper surface to the lower surface and into which the angular pin 12 is inserted.

The inclination angle θ ₁ , θ ₂ (see FIG. 4) of the inclined surface where the second ridge 54 is provided and the inclined hole 56 through which the angular pin 12 is inserted is the stroke of the molding die 1 (movable mold 101). Based on the size of the undercut portion P1, the molding portion 32 of the sliding piece 30 is determined to be disengaged from the undercut portion P1 when the mold is opened.

Note Increasing the inclination angle theta ₁ with respect to the horizontal direction of the second projections 54 (horizontal direction in FIG. 1), the amount of movement of the sliding piece 30 is increased relative to the amount of movement of the holding frame 50. Also when increasing the inclination angle theta ₂ with respect to the vertical direction of the inclined hole 56 (the vertical direction in FIG. 1), the amount of movement of the holding frame 50 with respect to the amount of movement of the movable mold 101 is increased.

Further, the holding piece 50 and the movable side template 108 are provided with

insertion holes

58 and 120 through which a bolt 48 for connecting the shaft portion 38 and the sliding portion 36 of the sliding piece 30 can be inserted. Thus, after the holder 20, the sliding piece 30 and the holding piece 50 are assembled into the movable side mold plate 108, the bolts 48 are passed through the insertion holes 58 and 120 to fix the sliding portion 36 and the shaft portion 38. it can.

Next, the operation of the molding die 1 of this embodiment will be described. When the molded product P is molded, a molding material is injected from the sprue bush 106 of the fixed mold 100 with the molding die 1 clamped, and the molding material is cured to mold the molded product P (see FIGS. 1 and 4). . At the time of molding, the upper surface 40 of the molding portion 32 of the sliding piece 30 of the undercut processing mechanism 10 is flush with the upper surface of the movable mold plate 108 and is in contact with the molded product P (molding material). The exposed portion 30 of the hollow portion 42 and the pin 34 forms the undercut portion P1 of the molded product P.

After the molded product P is molded, the mold 1 is opened. When the mold 1 is opened, the entire movable mold 101 moves downward in FIG. In conjunction with this, the holding piece 50 retreats (moves in the right direction in FIG. 1) along the horizontal groove 24 of the holder 20 by the action of the inclined hole 56 and the angular pin 12, and the sliding piece 30 moves along the dovetail groove accordingly. 46 and the second protrusion 54 of the holding piece 50 are moved along the oblique groove 22 of the holder 20, whereby the molding portion 32 of the sliding piece 30 is disengaged from the undercut portion P <b> 1 (see FIGS. 2 and 5). ).

After the mold 1 is opened, the molded product P is ejected. At the time of ejecting the molded product P, the ejector base plate 110 moves upward in FIG. 1, and the molded product P is ejected from the movable side mold plate 108 by the ejector pins 111 (see FIG. 3).

After taking out the molded product P, the molding die 1 is clamped again to form the next molded product P. At the time of clamping, the entire movable mold 101 moves upward in FIG. 3, and the ejector base plate 110 moves downward in FIG. In the undercut processing mechanism 10, the holding piece 50 moves forward along the horizontal groove 24 of the holder 20 by the action of the inclined hole 56 and the angular pin 12 in conjunction with the movement of the movable mold 101 (moves to the left in FIG. 3). Accordingly, the sliding piece 30 moves along the oblique groove 22 of the holder 20 by the action of the dovetail groove 46 and the second protrusion 54 of the holding piece 50, and the upper surface 40 of the molding portion 32 of the sliding piece 30 is moved. It is flush with the upper surface of the movable side template 108. When the mold clamping is completed, the molding material is injected and the next molded product P is molded.

As described above, according to the molding die 1 and the undercut processing mechanism 10 of the present embodiment, the holding piece 50 slides relative to the holder 20 in conjunction with the mold opening of the molding die 1. Since the sliding piece 30 slides relative to the holder 20 and moves so as to be detached from the undercut portion P1, the undercut portion P1 can be easily punched out while being compact and simple.

Further, according to the undercut processing mechanism 10 of the present embodiment, the sliding piece 30 and the holding piece 50 can be incorporated into the molding die 1 in a state of being partially accommodated in the holder 20, so that a compact configuration can be achieved. In addition, it is easy to attach to the molding die 1. In addition, for example, the sliding piece 30 and the holding piece 50 can be configured to be completely accommodated in the holder 20 during mold clamping.

Further, according to the molding die 1 and the undercut processing mechanism 10 of the present embodiment, the undercut processing mechanism 10 operates in conjunction with mold opening and clamping of the molding die 1 via the angular pin 12. The undercut portion P1 can be punched without providing a complicated drive mechanism.

As described above, the undercut processing mechanism, the molding die, and the molded product of the present invention have been described using the molding die 1 of the first embodiment, but the undercut processing mechanism, the molding die, and the molding of the present invention have been described. The product is not limited to the above embodiment, and can be used by being modified without changing the gist. For example, the restricting means between the holder 20 and the sliding piece 30 may be dovetail grooves and ridges. In this case, the holder 20 may be provided with dovetail grooves and the ridges on the sliding piece 30. The holder 20 may be provided with a ridge, and the sliding piece 30 may be provided with a dovetail groove. The same applies to the restricting means for the holder 20 and the holding piece 50. Similarly, the regulating means for the sliding piece 30 and the holding piece 50 may be provided with a ridge on the sliding piece 30 and a dovetail groove on the holding piece 50.

Further, in the undercut processing mechanism of the present invention, the oblique groove 22 and the protruding ridge 44, the horizontal groove 24 and the first protruding ridge 52, and the dovetail groove 46 and the second protruding ridge 54, which are fitted or engaged with each other, Alternatively, the cross-sectional shape of the engaging portion is not limited to the rectangle shown in the figure, and the cross-section of the fitting portion or the engaging portion may be a circle, a triangle, or the like. Further, in the undercut processing mechanism of the present invention, the restricting means of the holder 20, the sliding piece 30 and the holding piece 50 are not limited to those of the above embodiment, and for example, a linear guide or the like may be used. Good.

Further, the molded product that can be molded in the molding die of the present invention is not limited to one in which the undercut portion is a cylindrical boss. FIG. 8A and FIG. 8B are perspective views showing an example of a molded product that can be molded by the undercut processing mechanism and the molding die of the present invention. The undercut processing mechanism of the molding die of the present invention is orthogonal to the die cutting direction of the molded product P, particularly as in the undercut portions P1, P2, and P3 shown in the first embodiment and FIG. Parallel to the surface that has a hollow part or a space part formed by a molding member such as a pin 34 and has an undercut part in a longitudinal sectional view, which cannot be removed by a conventional loose core that moves in a direction. It can be suitably used for molding and die-cutting of an undercut portion having a plurality of protruding portions arranged in various directions.

In the molding die of the present invention, it is also possible to provide a plurality of undercut processing mechanisms. That is, according to the undercut processing mechanism and the molding die of the present invention, it is possible to mold and die-mold a molded product having an undercut portion such as a plurality of cylindrical bosses. Also, if the undercut protrusion direction of each undercut part, that is, the direction in which the die can be removed, is different, each undercut processing mechanism allows the corresponding undercut part to be die-released. It is only necessary to appropriately set the inclination angle of the regulating means such as the horizontal groove, the dovetail groove, the ridge, the angular pin, and the inclined hole of the holding piece.

Further, in the undercut processing mechanism and the molding die of the present invention, R chamfering, C chamfering, and the like may be applied to the corners and side ridges of each constituent member.

Moreover, the material of each structural member used for the undercut processing mechanism and molding die of the present invention is not limited to a specific material, and is used for a known undercut processing mechanism and molding die. What is necessary is just to use the thing similar to the material of a member suitably. However, it is preferable to use a material having a good slidability or a material subjected to a surface treatment having a good slidability for the sliding surface of each constituent member. Each sliding surface is not limited to surface contact, and may be line contact or point contact.

Further, the undercut processing mechanism of the present invention can be applied to a molding die that opens and closes horizontally, vertically, or in other directions.

Further, the undercut processing mechanism and the molding die of the present invention can be suitably used for a molding die such as a die-casting die, a mold press molding die, etc. in addition to the injection molding die.

As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily consider various changes and modifications within the obvious range by looking at the present specification. Therefore, such changes and modifications are interpreted as being within the scope of the invention defined by the claims.

DESCRIPTION OF SYMBOLS 1 Molding die 10 Undercut processing mechanism 12 Angular pin 20 Holder 22 Oblique groove 24 Horizontal groove 30 Sliding piece 32 Molding part 34 Pin 36 Sliding part 44 Projection 46 Dovetail groove 50 Holding piece 52 1st projection 54 1st 2 ridges P molded products P1, P2, P3 Undercut part

Claims

An undercut treatment mechanism that is attached to and used in a molding die for molding a molded product having an undercut portion, and that allows the undercut portion protruding in a direction intersecting the die cutting direction of the molded product to be die-cut. There,
A holder fixed to or integrally formed with the molding die;
A slide piece that molds the undercut portion, and a sliding piece that is slidable with respect to the holder so that the molded portion is detached from the undercut portion;
A holding piece that is slidable in a direction intersecting a die-cutting direction of the molded product with respect to the holder, and that holds the sliding piece slidably;
With
The sliding piece slides with respect to the holder so that the forming portion is detached from the undercut portion by sliding the holding piece with respect to the holder in conjunction with opening of the molding die. An undercut processing mechanism characterized by being configured to move.
The holding piece is opened through the mold and the mold through an inclined member attached to the mold so as to be inclined with respect to the mold opening and mold clamping direction. The undercut processing mechanism according to claim 1, wherein the undercut processing mechanism is configured to slide relative to the holder in conjunction with tightening.
The holder and the holding piece each include a regulating unit that regulates a moving direction of the sliding piece when the molding die is opened in a direction in which the molding part is detached from the undercut part. Item 3. The undercut processing mechanism according to Item 1 or 2.
The undercut processing mechanism according to any one of claims 1 to 3, wherein the holder is capable of partially or completely storing the sliding piece and / or the holding piece.
The slide piece includes a molding member that molds the hollow portion or space portion of the undercut portion so that the molded product having the hollow portion or space portion in the undercut portion can be formed. Item 5. The undercut processing mechanism according to any one of Items 1 to 4.
A molding die comprising the undercut processing mechanism according to any one of claims 1 to 5.
A molded product molded with the undercut processing mechanism according to any one of claims 1 to 5 or the molding die according to claim 6.