JPH11277544A - Mold for molding undercut and mold part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold for molding an undercut which can miniaturize the mold, reduce the number of part items, and facilitate assembling and mold part items. SOLUTION: This mold for molding an undercut is equipped with an upper mold 1, a lower mold 2 opposite to the upper mold 1 which has a guide through hole 9 slanted to the mold opening/closing direction in a molding surface 7, a core 3 which is inserted freely slidably into the through hole 9 and has an undercut molding surface 11 at the tip and a fitting part 12 and a guide receiving part 13 in the rear end part, an ejection member 4 which is fitted with the fitting part 12 freely slidably and slides the core 3 along the through hole 9, and a guide rod 5 which is inserted freely slidably into the guide receiving part 13 and guides the rear end part of the core 3 in the core 3 moving direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for undercut molding and a mold part.

[0002]

2. Description of the Related Art When an undercut molding core is obliquely penetrated into a lower mold, and the upper mold is opened and the molded product is pushed up from the lower mold, the undercut molding core is simultaneously pushed up to utilize the inclination posture of the core. FIG. 13 shows a conventional mold in which the undercut molding surface is removed from the undercut portion of the molded product. That is, 100 is an upper die, 101 is a lower die, 102 is an undercut molding core, 103 is a protruding member, 104 is a slide base, 105 is a guide rod, 106 is a guide plate, 107 is a holding table,
08 is a molded product, and 109 is a protruding means.

FIG. 13 shows a state in which molding is completed. Molded product 1
To remove 08, the upper mold 100 is opened with respect to the lower mold 101, and then the molded product 108 is pushed up by the ejecting means 109 and separated from the lower mold 101. In this case, by moving the protruding member 103 simultaneously with the protruding means 109 to raise the core 102 in the inclined direction, the undercut molding surface 110 is slid and separated from the undercut portion 108a of the molded product 108. When the protruding member 103 is lifted, the slide base 104 slides in the direction of the arrow along the longitudinal direction of the guide rod 105, thereby causing the core 10 to move upward.
The core 102 is pushed up while guiding the rear end of the core 102.
When the projecting member 103 is retracted, the core 102 returns to the original position.

As described above, since the rear end side of the core 102 is guided by the guide rod 105, the core 102 can slide smoothly, and the lower die 1 through which the core 102 penetrates is formed.
01 can prevent the sliding surface on the rear end side of the guide through hole 101a from being worn out.

[0005]

However, in this conventional example, a space for providing the guide rod 105 is required on the side of the core 102, which increases the size of the mold, increases the number of parts, and increases the number of parts. There is a disadvantage that the assembly of the mold is complicated. Accordingly, it is an object of the present invention to provide a mold for undercut molding and a mold component that can reduce the size of the mold, reduce the number of parts, and facilitate assembly.

[0006]

According to a first aspect of the present invention, there is provided an undercut molding die having an upper die and a guide through hole which is inclined with respect to the opening / closing direction of the die, and is opposed to the upper die. A lower die, a core that is slidably inserted into the guide through hole, has an undercut molding surface at the tip, and has a mounting portion and a guide receiving portion at the rear end, and the mounting portion is slidably mounted. A protruding member for sliding the core along the guide through-hole, and a guide rod for slidably inserting the core into the guide receiving portion and guiding the rear end side of the core in the moving direction of the core. Things.

According to the undercut molding die of the first aspect, since the guide receiving portion is provided on the core and guided by the guide rod, the guide rod is positioned on the line in the moving direction of the core, so that it is compared with the conventional example. To make the mold smaller,
In addition, the number of parts can be reduced, so that assembly can be facilitated. The undercut molding die component according to claim 2, wherein the core has a guide receiving portion at a rear end portion slidably inserted into an inclined guide through hole of a lower die facing the upper die, and the core of the core. A mounting portion slidably mounted on a protruding member provided at a rear end portion for protruding the core toward the front end, and a rear end side of the core inserted into the guide receiving portion and moved in a moving direction of the core. And a guide rod for guiding.

According to the undercut molding die part of the second aspect, the same effect as that of the first aspect is obtained. Claim 3
The undercut molding die component described above is a core that is slidably inserted into an inclined guide through hole of a lower die facing the upper die, has an undercut molding surface at a front end, and has a guide receiving portion at a rear end. A mounting portion provided at the rear end of the core and slidably mounted on a protruding member for protruding the core toward the front end; and a rear end side of the core inserted into the guide receiving portion. A guide rod for guiding the core in the moving direction.

According to the third aspect of the present invention, there is provided an effect similar to that of the first aspect. Claim 4
In the undercut molding die part according to claim 2, in claim 2 or claim 3, the mounting portion is provided so as to protrude in a direction orthogonal to a mold opening direction of a rear end portion of the core and a tilt direction of the core. It comprises a pin and a rail having a slit through which the pin is slidably inserted and attached to the protruding member.

According to the undercut molding die part of the fourth aspect, in addition to the same effects as in the second or third aspect, the core is slidably protruded easily by attaching the rail to the protruding member. Can be attached to a member. According to a fifth aspect of the present invention, in the undercut molding die part according to the fourth aspect, the rail penetrates a long hole along one longitudinal side of one opposing side surface of the rectangular body and is adjacent to the one opposing side surface. Slits communicating with the long holes are formed in the surface along the longitudinal direction, and the rear end of the core is slidably inserted into the long holes and both ends of the pins are slidable in the slits It is inserted through.

According to the undercut molding die part of the fifth aspect, in addition to the same effect as the fourth aspect, by providing a pair of slits for supporting both ends of the pin on one rail, it is possible to apply the same to the projecting member. Installation becomes easy. The mold part for undercut molding according to claim 6 is,
In Claim 3, Claim 4, or Claim 5, the guide rod is attached to a mounting member so that its rear end is rotatable, and the mounting member is mounted to a holding table.

According to the undercut forming die part of the sixth aspect, in addition to the same effect as the second, third, fourth or fifth aspect, the guide rod is rotated via the mounting member. Since it is movably mounted on the holder, the mounting member can be easily mounted. According to a seventh aspect of the present invention, in the undercut molding die part according to the second, third, fourth or fifth aspect, the guide receiving portion of the core is formed along a longitudinal direction of the core. It is a tubular body with both ends open.

According to the undercut molding die part of the seventh aspect, in addition to the same effects as those of the second, third, fourth or fifth aspect, a width equal to or greater than the width of the core can be obtained. The inserted guide rod can be inserted and can be applied to a small core. According to an eighth aspect of the present invention, there is provided the undercut molding die part according to the second, third, fourth or fifth aspect, wherein the core has a core piece having an undercut molding surface, and A holding portion having a detachable portion for detachably attaching the end at the front end, the mounting portion on the rear end side, and the guide receiving portion.

According to the undercut molding die part of the eighth aspect, in addition to the same effects as those of the second, third, fourth, or fifth aspect, the undercut molding die parts are held for a plurality of types of core pieces. Since the parts can be shared, the core can be easily manufactured.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. That is, the undercut molding die includes the upper die 1, the lower die 2, the core 3, the protruding member 4, and the guide rod 5. Upper mold 1
Is configured to move downward when closing the mold and move upward when opening the mold in the embodiment. 6 is the molding surface.

The lower die 2 has a guide through-hole 9 which is inclined with respect to the opening and closing direction of the die on the molding surface, and is opposed to the upper die 1. The inclination angle of the guide through hole 9 is determined according to the shape of the undercut portion 36a of the molded product 36 (see FIG. 6) to be molded. 7a is a molding surface for molding the outer surface side of the undercut portion 36a of the molded product 36, and 8 is a template for holding the lower mold 2, which is fixed in the embodiment. Reference numeral 10 denotes a loose fitting hole communicating with the guide through hole 9.

The core 3 is slidably inserted into the guide through-hole 9 and has an undercut molding surface 11 at the tip.
At the rear end, a mounting portion 12 and a guide receiving portion 13 are provided.
The mounting portion 12 according to the embodiment has a pin 14 protruding in a direction perpendicular to the mold opening direction of the rear end of the core 3 and the direction of inclination of the core 3, and a slit 16 through which the pin 14 is slidably inserted. Rail 17 attached to the protrusion member 4
Consists of The rail 17 penetrates the long hole 15 along the longitudinal direction on one opposing side surface of the rectangular body, and has slits 16 communicating with the long hole 15 along the longitudinal direction on both side surfaces adjacent to the one opposing side surface, respectively. Has formed. A rail 17 is attached to the recess 18 of the protruding member 4 such that the rear end of the core 3 is slidably inserted into the elongated hole 15 and both ends of the pin 14 are slidably inserted into the slit 16. In this case, when the center of the pin 14 is attached to the core 3 through the slit 16 by inserting the rear end of the core 3 into the elongated hole 15, both ends of the pin 14 are supported by the slit 16 and assembled. The long hole 15 of the rail 17 is attached to the protruding member 4 so as to face in a direction perpendicular to the opening and closing direction of the mold and in a direction in which the core 3 is inclined from the opening and closing direction of the mold.

The guide receiving portion 13 of the embodiment is a blind hole dug from the rear end face of the core 3. When the core 3 is formed, for example, as shown in FIGS. 3 (e) and 3 (f), the pin hole 30 and the guide receiving portion 13 are formed in a rod-like body having a rectangular cross section, for example, and the user can adjust the angle according to the inclination angle. Then, the rear end face 35 is cut horizontally to form an inclined face 35a and the undercut forming face 11 is processed.

The protruding member 4 has the mounting portion 12 slidably mounted thereon and slides the core 3 along the guide through hole 13. In the embodiment, the rail 17 is housed in the concave portion 18 of the protruding member 4 and is attached and fixed. 33 is core 3
And a loose fitting hole into which the guide rod 5 is loosely fitted.
The guide rod 5 is slidably inserted into the guide receiving portion 13 to guide the rear end side of the core 3 in the moving direction of the core 3.
The guide rod 5 of the embodiment has its rear end rotatably attached to a mounting member 20, and the mounting member 20 is mounted to a holding table 19. The mounting member 20 forms a groove 34 for inserting the base 5 a provided at the rear end of the guide rod 5, and has a pin receiving hole that penetrates both sides of the groove 34 and fits the pin 21.
The screw insertion hole 22 is formed adjacent to the groove 34. The guide rod 5 is rotatably mounted on the mounting member 21 by the pin 21, the screw 23 is inserted into the screw insertion hole 22,
When the screw is screwed into the screw hole 24 formed in the mounting member 9, the mounting member 20 is mounted in the concave portion 45 of the holding base 19.

In such an undercut molding die, the undercut molding die component includes an inclined guide through hole 9 of the lower die 2 opposed to the upper die 1 as shown in FIG.
3 which is slidably inserted into the core and has an undercut molding surface 11 at the front end and a guide receiving portion 13 at the rear end.
A mounting portion 12 provided at a rear end of the core 3 and slidably mounted on a protruding member 4 for protruding the core 3 toward the front end; and a rear end side of the core 3 inserted into the guide receiving portion 13. And a guide rod 5 for guiding the core 3 in the moving direction of the core 3.

FIG. 6 shows the releasing operation after molding. FIG. 1A shows a state in which a molding material is injected into a cavity formed by the upper mold 1, the lower mold 2 and the core 3 and hardened to form a molded article 36 having an undercut portion 36a. FIG. 3B shows a state in which the upper mold 1 is moved to open the mold and the molded product 36 is exposed. FIG. 3C shows a state in which the molded article 36 is pushed out from the lower mold 2 by the ejecting means (not shown) and the ejecting member 4 is moved upward. At this time, the front end side of the core 3 is guided by the guide through hole 9 of the lower mold 2, the rear end side of the core 3 is guided by the guide rod 5 and the rail 17, and the pin 14 is guided by the slit 16,
The core 3 moves smoothly in the longitudinal direction while the rear end side moves along the longitudinal direction of the long hole 15 of the rail 17. Since the molded product 36 moves in the direction of the upper mold 1, the undercut molding surface 17 of the core 3 moves away from the undercut portion 36 a of the molded product 36. Figure (d)
Moves the projecting member 4 to the maximum movement position, the undercut molding surface 17 is completely separated from the undercut portion 36a, and the molded product 36 can be removed from the core 3.

In the case of the next molding, the projecting member 4 is lowered, the upper mold 1 is lowered to the lower mold 2 and the mold is closed, as shown in FIG. According to the first embodiment, since the guide receiving portion 13 is provided on the core 3 and guided by the guide rod 5, the guide rod 5 is positioned on the movement direction line of the core 3. The size of the mold can be reduced, and the number of parts can be reduced, so that assembly can be facilitated.

The above-described mold parts for undercut molding can provide the same functions and effects. Furthermore, the mounting portion 12 has a pin 1 protruding in a direction perpendicular to the mold opening direction of the rear end of the core 3 and the inclination direction of the core 3.
4 and a rail 17 having a slit 16 through which the pin 14 is slidably inserted and attached to the protruding member 4.
Therefore, by attaching the rail 17 to the protruding member 4, the core 3 can be slidably mounted on the protruding member 4 easily.

A rail 17 penetrates the elongated hole 15 along the longitudinal direction on one side of the rectangular body, and slits 16 communicate with the elongated hole 15 along the longitudinal direction on both sides adjacent to the opposite side. Since the rear end of the core 3 is slidably inserted into the elongated hole 15 and both ends of the pin 14 are slidably inserted into the slits 16, a pair of pins that support both ends of the pin 14 is provided. By providing the slit 16 on one rail 17, attachment to the protruding member 4 becomes easy.

The guide rod 5 has its rear end rotatably mounted on the mounting member 20, and the mounting member 20 is mounted on the holder 19, so that the mounting member 20 can be easily mounted. FIG. 7 shows a modification of the core, in which the core is slightly thinner than in the first embodiment, and
Projection 3 for forming pin hole 39 in the portion where 4 is to be attached
8 is provided.

FIG. 8 shows a second embodiment of the present invention. That is, this undercut molding die is the first type.
In the embodiment, the guide receiving portion 13 of the core 3 is formed as a cylindrical body formed along the longitudinal direction of the core 3 and having both ends opened. The mounting member 20 'is a screw hole 41.
The screw 23 inserted into the screw insertion hole 42 formed in the holding table 19 is screwed into the recess 43 formed in the holding table 19.

The other points are the same as in the first embodiment. 9 to 11 show a third embodiment of the present invention. That is, this undercut molding die is the first type.
In the embodiment of the present invention, the core 3 has a core piece 47 having the undercut molding surface 11 and a detachable portion 49 for detachably attaching the rear end of the core piece 47 at the front end, and the mounting portion 12 on the rear end side. And a holding portion 48 having a guide receiving portion 13.

The core piece 47 of the embodiment has, for example, a concave hooking portion 50 formed on the side surface of the rear end portion, and the holding portion 48 has a fitting groove 51 that fits into the rear end portion of the core piece 47, preferably a rear portion. Forming a fitting groove 51 that fits in close contact with the three adjacent side surfaces of the end, and forming, for example, a convex hook receiving portion 52 that hooks on the hook portion 50, and the attaching / detaching portion 49 is slidable on the holding portion 48. Is a cylindrical body fitted externally, and an extension piece 5
3 is provided, and an inward projection 54 is provided at the tip of the extension piece 53. A concave portion for sliding the detachable portion 49 onto the fitting groove 51 in which the core piece 47 of the holding portion 48 is fitted, and locking the inward projection 54 in a state where the rear end portion of the core piece 47 is covered by the detachable portion 49. 55 are formed.

The other points are the same as in the first embodiment. In the present invention, the upper mold and the protruding member are movable when the mold is opened, but the upper mold and the protruding member may be fixed and the lower mold may move when the mold is opened.

[0030]

According to the first aspect of the present invention, since the guide receiving portion is provided on the core and guided by the guide rod, the guide rod is located on the line in the moving direction of the core. The mold can be downsized and the number of parts can be reduced as compared with that of the first embodiment.

According to the undercut molding die part of the second aspect, the same effect as that of the first aspect is obtained. Claim 3
According to the undercut molding die part described above, the same effect as that of the first aspect is obtained. According to the undercut molding die part of the fourth aspect, in addition to the same effect as the second or third aspect, the core is slidably mounted on the protruding member easily by assembling the rail by mounting the rail on the protruding member. be able to.

According to the undercut molding die part of the fifth aspect, in addition to the same effects as in the fourth aspect, by providing a pair of slits for supporting both ends of the pin on one rail, the projecting member can be formed on the rail. Installation becomes easy. According to the undercut molding die part of the sixth aspect, in addition to the same effect as the second, third, fourth or fifth aspect, the guide rod is rotatable via the mounting member. Since the mounting member is mounted on the holder, mounting of the mounting member is facilitated.

According to the undercut molding die part of the seventh aspect, in addition to the same effects as those of the second, third, fourth or fifth aspect, a width equal to or greater than the width of the core is obtained. The inserted guide rod can be inserted and can be applied to a small core. According to the undercut molding die part of the eighth aspect, in addition to the same effect as the second, third, fourth, or fifth aspect, the holding portion is shared by a plurality of types of core pieces. The core can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a first embodiment of the present invention in a mold-clamped state.

FIG. 2 is a partial sectional side view of a mold part for undercut molding.

FIG. 3 shows a rear end of a core, where (a) is a front view,
(B) is a side view, (c) is an end view of a rear end face, (d)
FIG. 3 is an end view of the rear end face as viewed in the longitudinal direction, FIG. 2E is a side view of the state before the rear end face is obliquely cut, and FIG.

4 (a) is a front view, FIG. 4 (b) is a plan view, and FIG. 4 (c) is a sectional view.

5 (a) is a plan view, FIG. 5 (b) is a sectional view, FIG. 5 (c) is a bottom view, and FIG. 5 (d) is a left side view.

FIG. 6 is an explanatory diagram illustrating an opening operation of a mold.

FIGS. 7A and 7B show a rear end portion of a modified embodiment of the core, wherein FIG. 7A is a front view, FIG. 7B is a front view, and FIG. 7C is a rear end view.

FIG. 8 is a partial cross-sectional view of the second embodiment.

FIG. 9 is a sectional view of a mold part according to a third embodiment.

FIG. 10 shows the core piece, (a) is a front view, (b)
Is a side view thereof.

FIG. 11 is a plan view of a detachable unit.

FIGS. 12A and 12B show a holding unit, wherein FIG. 12A is a side view of the holding unit in which an attaching / detaching unit is sectioned, and FIG. 12B is a sectional view thereof.

FIG. 13 is a partial sectional view of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 upper die 2 lower die 3 core 4 projecting member 5 guide rod 9 guide through hole 11 undercut forming surface 12 mounting part 13 guide receiving part 14 pin 15 long hole 16 slit 17 rail 19 holding base 20 mounting member 47 core piece 48 holding Part 49 Detachable part

Claims (8)

[Claims] 1. An upper die, a lower die having a guide through-hole inclined with respect to the opening / closing direction of the die on a molding surface, and a lower die facing the upper die. A core having an undercut molding surface and having a mounting portion and a guide receiving portion at a rear end thereof, and a protruding member to which the mounting portion is slidably mounted and slides the core along the guide through hole, A guide rod for slidably inserted into the guide receiving portion and guiding a rear end side of the core in a moving direction of the core; 2. A core slidably inserted into an inclined guide through hole of a lower die facing an upper die and having a guide receiving portion at a rear end portion, and the core provided at the rear end portion of the core. And a guide rod slidably mounted on a protruding member for protruding toward the front end, and a guide rod inserted into the guide receiving portion and guiding a rear end side of the core in a moving direction of the core. Mold parts for cut molding. 3. A core which is slidably inserted into an inclined guide through hole of a lower die facing an upper die, has an undercut molding surface at a front end, and has a guide receiving portion at a rear end, and a core of the core. A mounting portion slidably mounted on a protruding member provided at a rear end portion for protruding the core toward the front end, and a rear end side of the core inserted into the guide receiving portion and moved in a moving direction of the core. An undercut molding die component having a guide rod for guiding. 4. The mounting portion has a pin protruding in a direction orthogonal to a mold opening direction of a rear end portion of the core and a direction of inclination of the core, and a slit through which the pin is slidably inserted. The undercut molding die part according to claim 2 or 3, comprising a rail attached to the protruding member. 5. A slit which penetrates a long hole along one longitudinal side on one opposing side surface of a rectangular body, and communicates with the long hole along a longitudinal direction on both side surfaces adjacent to the one opposing side surface. 5. The undercut molding metal according to claim 4, wherein a rear end of the core is slidably inserted into the elongated hole, and both ends of the pin are slidably inserted into the slit. Mold parts. 6. The guide rod according to claim 2, wherein the rear end of the guide rod is rotatably mounted on a mounting member, and the mounting member is mounted on a holding table.
The undercut molding die part described in the above. 7. The core according to claim 2, wherein the guide receiving portion of the core is a cylindrical body formed along the longitudinal direction of the core and having both ends opened. Mold parts for undercut molding. 8. The core has a core piece having an undercut molding surface, an attaching / detaching part for detachably attaching a rear end of the core piece at a front end, and the attaching part at a rear end side, and further comprising the guide. The undercut molding die part according to claim 2, comprising a holding part having a receiving part.