JPH0624746B2 - Mold for products with screws - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a mold for threaded products.

2. Description of the Related Art FIG. 1 shows a threaded product a such as a cap of a container molded by the mold of the present invention, and a thread c is formed on the inner circumference of a flange b thereof.

5 to 7 show a conventional typical mold for molding such a product 1.

This mold consists of a fixed mold 31 and a movable mold 32.
35 is attached to the fixed plate 31 ', and the movable core 40 is composed of a fixed core 33 attached to the movable plate 32' and a rotating core 38 slidably fitted on the outer periphery thereof. A core insert 34 is arranged inside the fixed core 33 with a gap 37, and a cooling water passage is formed by the center hole 36 of the core insert 34 and the gap 37. A flange 39 is formed in the middle of the rotating core 38, and the gear portion 41 is provided on the outer periphery of the flange 39.
Bushing 4 formed on both sides of the flange 39
A core retainer plate 44 is rotatably held via 2, 43, and a stripper ring 46 is fitted to the front portion of the core retainer plate 44.
The stripper ring 46 is attached to the stripper plate 48 by bolts 47. At the tip of the stripper ring 46, a protrusion (not shown) with which the flange b of the product a is engaged is provided.

A first rack rod 49, which is vertically movable in a core retainer plate 44, meshes with the gear 41. And movable 32
A first gear 51 that meshes with the first rack rod 49 is rotatably provided on the upper part of the rotary shaft 52 by a rotary shaft 52, and a second gear 53 is attached to the rotary shaft 52. A second rack bar 54 provided horizontally is meshed with the upper part of the. An inclined surface that becomes gradually narrower toward the lower side of the core retainer plate 44 side of the lower portion of the first rack rod 49.
45 is formed, and a pin 50 is fixed to the stripper plate 48 at a position facing the inclined surface, the pin 50 is slidably fitted in the through hole 55 of the core retainer plate 44, and the tip thereof contacts the inclined surface 45. Touching.

In such a mold, in the mold closed state shown in FIG. 5, the cavity 56 is made by the material injected from the nozzle 57.
When the mold is opened after molding with the second mold, the second gear 53 is rotated by the second rack rod 54 as the movable mold 32 moves backward,
The first gear 51 attached to 52 automatically rotates together, and the first rack rod 49 meshing with the first gear 51 moves downward.
This downward movement of the first rack rod 49 causes the rotating core 38 having the gear 41 to mesh with the first rack rod 49 to rotate, and also the inclined surface.
The pin 50, whose tip is in contact with 45, is pushed by the inclined surface 45 and moves rightward in FIG. 4 together with the stripper plate 48, and this movement causes the stripper ring 46 provided on the stripper plate 48 to move in the same direction. To move the product a in the same direction, so that the product a is released from the rotating core 38.

In order to perform such an action, the inclined surface 45 of the first rack rod 49 is set to an angle corresponding to the lead angle of the screw c of the product a.

The screw type product mold is as described above, the movable core is divided into the fixed core 33 and the rotary core 38, and the flange b of the product a is formed by the rotary core 38. However, since the product a is taken out while rotating it, it is not possible to cool it directly, and the movable core 38 must be indirectly cooled by cooling the core insert 34. Since the cooling effect is poor and the molding cycle becomes long, and the stripper plate 48 must be provided,
There is a problem that the structure is complicated and the entire mold becomes large.

An object of the present invention is to solve the problems of the conventional mold as described above, to allow direct cooling while keeping the movable side core fixed, and thereby to shorten the molding cycle. Another object of the present invention is to provide a mold that does not require a stripper plate like a mold and can be downsized as a whole.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention has a fixed die and a movable die, the movable side core is formed by a fixed core, and a screw molding is made at the tip of this fixed core. Part is formed,
A stripper member is slidably fitted on the outer periphery of the thread forming portion.The stripper member has a female screw portion on the inner rear inner periphery, a driven gear portion on the central outer periphery, and a stripper ring engaging the product on the front portion. The stripper member has a female threaded portion which is screwed with a male threaded portion provided on the outer periphery of the fixed core, and a driven gear portion is meshed with a main driving gear rotatably provided in the movable die. Is fixed to a screw rod rotatably installed in the movable mold, and this screw rod is screwed to a screw portion provided in the fixed mold.

Further, the screw portion provided on the fixed die does not rotate, but is movable in the axial direction by a distance substantially equal to the distance for the product to be removed from the fixed core of the fixed die.

Operation In the mold of the present invention as described above, when the mold is opened after the molding is completed, the screw rod screwed into the female thread portion of the fixed mold is rotated as it is retracted, and this rotation fixes it. The driven gear is rotated, and the strip member having the driven gear that meshes with the driven gear is fixed because the male screw portion provided on the strip member is screwed with the male screw portion of the fixed core. The product moves forward along the core while rotating, and the product is extracted while rotating from the fixed core.

Embodiments In the embodiments of the present invention shown in FIGS. 2 and 3, 1 is a fixed type, 2 is a movable type, 1'and 2'represent fixed plates and movable plates thereof, and a fixed side core is attached to the fixed plate 1 '. 5
However, a fixed core 3 forming a movable side core is attached to the movable plate 2 ', a core insert 4 is attached to the tip of the fixed core 3, and the fixed plate 3 is provided on the movable plate 2', the fixed core 3 and the core insert 4. The central hole 6 and the outer hole 7 provided outside the central hole 6 communicate with each other to form a cooling water passage.

A tubular stripper member 9 is slidably fitted on the outer periphery of the fixed core 3 via a bush 8. The stripper member 9 is composed of a member main body 10, a rear nut member 13 and a front stripper ring 14. The members 10, 13 and 14 are integrally connected by a bolt 15, and the nut member 13 has a female screw portion 12 that is screwed to a male screw portion 11 provided on the outer periphery of the fixed core 3 and is provided on the outer periphery of the member body 10. Is provided with a driven gear unit 16. The stripper ring 14 has a projection similar to the conventional example, which engages with the product.

A screw rod 17 is horizontally arranged between the upper portions of the fixed die 1 and the movable die 2 which face each other, and the head of the screw rod 17 is rotatably supported inside the movable die 2 and A driving gear 18 that meshes with a driven gear portion 16 of the stripper member 9 is attached. In this case, the leads of the screw parts 11 and 12 are the same as the leads of the screw c of the product a.

A nut member 21 having a female thread portion 19 that is screwed into a threaded rod 17 is provided on an upper portion of the fixed die 1 between the fixed die body and the support members 25 and 26 which are engaged with bolts (not shown). The nut member 21 is slidably fitted in the support hole 29 of
It is movable in the axial direction within the distance X shown in the figure, but is not rotatable. A return block 24 is attached to the block 24. The block 24 is a slot provided in the supporting member 25 in the axial direction. It is slid into 30.

Then, above the driving gear 18 of the movable die 2, the screw rod 17
A push rod 23 is arranged parallel to the fixed die 1 so as to face the fixed die 1. The push rod 23 slidably fits into the slot 30 of the support member 25 when the die is closed and abuts the return block 24 to move the nut member 21 by the distance X. It is designed to move backwards.

In the above-mentioned case, when the mold is closed as shown in FIG.
When the mold is opened after molding with 28, as shown in FIG. 3, the screw rod 17 screwed into the female screw portion 19 of the nut member 21 is automatically retracted and retracted as the movable mold 2 retracts. Turn to. Along with the rotation of the screw rod 17, the stripper member 9 having the main driving gear 18 and the driven gear portion 16 meshing with the main gear 18 is rotated, and the rotation causes the screw portion provided on the inner periphery of the stripper member 9.
Since 12 is screwed with the male screw portion 11 of the fixed core 3, the stripper member 9 advances while rotating. Then, the stripper ring 14 at the tip of the product a holds and holds the product a and advances it to remove the product a from the fixed core.

In this case, since there is a gap X between the support member 26 and the nut member 21 when the mold is closed (FIG. 2), the screw rod 17 does not rotate in the initial stage of mold opening, and the shaft does not rotate together with the nut member 21. In the direction shown in FIG. 3, the nut member 21 comes into contact with the support member 26 as shown in FIG.
The rotation of 17 begins. As a result, when the stripper member 9 is rotated at the same time when the mold is opened, it is prevented that the product a and the stationary core 5 of the stationary mold 1 are subjected to rotational friction to damage the product a.

EFFECTS OF THE INVENTION The present invention is as described above. When the mold is opened, the male screw portion provided on the fixed die rotates the screw rod provided on the movable die and screwed into the female screw portion. The rotation of the stripper member is caused by the engagement of the main drive gear and the driven gear portion of the fixed type stripper member, and at the same time, the screw portion provided on the stripper member is screwed with the male screw portion provided on the fixed core to form the stripper member. By moving forward,
Since the product is die-cut and the movable core is a fixed core, the cooling water supply passage can be formed directly in this core to enhance the cooling effect and shorten the molding cycle. In addition, unlike the conventional one, it is not necessary to interpose a stripper plate or the like between the fixed die and the movable die, and the entire volume can be reduced by that amount. As is apparent from the figure, the main gear is exposed to the outside when the mold is opened, which has an effect that maintenance work such as grease up and backlash check of this portion is easy.

[Brief description of drawings]

1 is a vertical sectional front view of a product molded by a mold of the present invention, FIG. 2 is a vertical sectional front view of the embodiment of the present invention when the mold is closed, and FIG. 3 is a vertical sectional front view of the same when the mold is opened. , Fig. 4 is the third
5 is a vertical cross-sectional front view of a conventional mold of the same kind as the mold of the present invention when the mold is closed, and FIG. 6 is a vertical cross-sectional front view of the main part of the same. FIG. 7 is a sectional view taken along line 7-7 of the above. 1 ... Fixed type, 1 '... Fixed plate 2 ... Movable type, 2' ... Movable plate 3 ... Movable side fixed core 5 ... Fixed side fixed core 6 ... Center hole, 7 ... Outside hole 9 ... Stripper member, 10 ... Member body 11 ... Male screw part, 12 ... Female screw part 13 ... Nut member, 14 ... Stripper ring 16 ... Driven gear part, 17 ... Screw rod 18 ... … Main drive gear, 19… Female thread 21… Nut member, 26… Support member

Claims (2)

[Claims] 1. A fixed mold and a movable mold, wherein a movable core is formed by a fixed core, a screw molding portion is formed at a tip end portion of the fixed core, and a stripper member slides on an outer periphery of the screw molding portion. The stripper member is provided with a female screw portion on the rear inner periphery, a driven gear portion on the central outer periphery, and a stripper ring for engaging the product on the front portion, and the female screw portion of the stripper member is a fixed core. The male gear is screwed on the outer periphery of the driven gear, the driven gear is meshed with the main gear that is rotatably provided in the movable die, and the main gear is a screw that is rotatably provided in the movable die. A metal mold for a screwed product, which is fixed to a rod, and this screw rod is screwed into a screw portion provided on the fixed die. 2. The threaded product mold according to claim 1, wherein the threaded portion provided on the fixed die does not rotate, but is substantially equal to the distance for the product to be die-cut from the stationary core of the fixed die. It can be moved in the axial direction by a distance.