JP7061246B1 - Mold forming machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact mold forming machine which has a simple structure and can be reliably held by itself. A mold forming machine includes a mold, a mold operating cylinder 30, a mold clamping device 50, and the like. The mold operation cylinder 30 is mounted on the first block 10 attached to the support base. The mold operation cylinder 30 projects vertically upward from the first block 10 (direction from the second block 20 to the first block 10), and has a piston rod penetrating the first block. .. The piston rod is connected to the second block 20. The mold clamping device 50 is for limiting the mutual movement between the first block 10 and the second block 20, and two of the mold clamping devices 50 are fixed to the side surfaces 15 and 15 of the first block 10, for a total of four. With the mold operation cylinder 30 operated and the first block 10 and the second block 20 in surface contact with each other, the mold clamping device 50 is operated to mold the mold. [Selection diagram] Fig. 2

Description

The present invention relates to a mold forming machine capable of mutually holding blocks constituting a mold.

An injection molding machine for molding a plastic product is generally a mechanism in which one of a pair of mold blocks is attached to a support base and the other is attached to a base base in a slidable state and can be opened and closed mutually. In such a mechanism, a large pressure is generated in the mold while the molten plastic is injected into the mold. Therefore, it is necessary to tighten at high pressure using a mold clamping device so that the mold does not open.

There are two types of mold clamping devices: a direct pressure type that operates and tightens a large hydraulic cylinder, and a toggle type that tightens using a link mechanism, but both methods are large-scale devices. In addition, the support base is inevitably large because it is necessary to support the reaction force of the hydraulic cylinder and the link mechanism.

In order to make the injection molding machine compact, a self-holding mold device has been proposed. Patent Document 1 The proposed self-holding mold device is used in an injection molding machine for injection molding a rubber molded product. Specifically, it is provided with a pair of molds, that is, an upper mold and a lower mold, and a metal holding member for holding a mold clamping force between the upper mold and the lower mold, and the holding member is slid on the lower mold. The guide member that freely supports is fixed via the mounting bolt. The upper mold is configured by attaching a thin plate-shaped mounting plate to a rectangular mold portion, and similarly, the lower mold is configured by attaching a thin plate-shaped mounting plate to the mold portion. The facing lower surface and the upper surface of each mold portion are divided surfaces that can be surface-contacted with each other without a gap. The holding member is pressed against the other end side with a predetermined mounting force. As a result, the holding member moves to the other end side B, the engaging surface, the upper surface, and the lower surface are pressed and held, and the holding member becomes a wedge to hold the mold between the upper mold and the lower mold.

Japanese Unexamined Patent Publication No. 9-207138

However, the invention proposed in Patent Document 1 has problems such as the need to attach a mounting plate to the mold and the complicated shape of the member required for self-holding the mold. Further, since each of the holding members slides in opposite directions to each other, it is necessary to take measures to prevent the mold from twisting during sliding.

The present invention has been made by paying attention to these problems, and proposes a compact mold forming machine that can be reliably held by itself with a simple structure.

The invention for solving the above problems is a mold molding machine, in which a first block including a first contact surface and a second block including a second contact surface and cooperating with the first block to define a cavity. The second block comprises a mold having a block, a mold operating cylinder that changes the distance between the first block and the second block, and a mold clamping device fixed to each of the opposite side surfaces of the first block. , The wedge member has an inclined surface defined by a groove provided on the surface facing the second contact surface, and the mold clamping device includes a wedge member that molds the mold by surface contact with the second block and a wedge member. It has an accommodating portion provided with an accommodating hole for accommodating the wedge member, and a mold clamping cylinder for moving the wedge member in the axial direction orthogonal to the side surface, and the wedge member has a first wedge surface extending along the axial direction. It has a second wedge surface facing the first wedge surface, and the accommodation hole is in a state where the accommodation surface is defined and the mold operation cylinder is operated to bring the first contact surface and the second contact surface into surface contact. When the mold clamping device is operated, the first wedge surface comes into surface contact with the inclined surface, and the second wedge surface comes into surface contact with the accommodating surface, whereby the mold is molded.

According to this configuration, the mold is molded by operating the mold clamping device to bring the wedge member into surface contact with the second block in a state where the first contact surface and the second contact surface are in surface contact. The wedge member limits the relative movement of the first and second blocks even when the molten plastic is injected into the cavity and a large pressure is applied to the cavity.
According to this configuration, the wedge member has a first wedge surface extending along the axial direction and a second wedge surface facing the first wedge surface, and the first wedge surface is in surface contact with the inclined surface and is in surface contact with the inclined surface. Since the second wedge surface comes into surface contact with the accommodating surface to clamp the mold, the displacement of the wedge member is suppressed by the surface contact with the accommodating portion even when a large pressure is generated in the cavity. As a result, the relative movement between the first block and the second block is restricted, and the self-holding is ensured.
According to this configuration, even when a large pressure is generated in the cavity, the displacement of the wedge member is suppressed by the surface contact of the accommodating surface with the second wedge surface.

Preferably, the inclination angle of the first wedge surface and the second wedge surface with respect to the axial direction is 0 to 45 degrees.

By setting the inclination angle of the first wedge surface and the second wedge surface with respect to the axial direction from 0 degree to 45 degrees, the first block and the second block can be efficiently self-held. As a result, the mold clamping cylinder can be made compact.

Preferably, the second block is provided with a groove, and the wedge member is fitted into the groove.

According to this configuration, since the wedge member fits into the groove provided in the second block, lateral displacement between the first block and the second block can be avoided when the wedge member comes into surface contact with the second block.

Preferably, the wedge member has a pair of wedge wall surfaces extending along the axial direction, and the groove has a pair of inclined surfaces corresponding to the first wedge surface and a pair of groove wall surfaces corresponding to the pair of wedge wall surfaces. It is characterized by.

According to this configuration, the wedge member has a pair of wedge wall surfaces extending along the axial direction, and the groove has an inclined surface corresponding to the first wedge surface and a pair of groove wall surfaces corresponding to the pair of wedge wall surfaces. Therefore, the second block and the wedge member can be fitted with a simple structure.

Preferably, the first block is provided with a first cavity portion that is detachably fixed, and the second block is provided with a second cavity portion that is detachably fixed, and the first cavity portion and the second cavity portion are provided. Is characterized in that they work together to define the cavity.

According to this configuration, since the first cavity portion and the second cavity portion that collaborate to define the cavity are removable, it is possible to easily manufacture molded products having different shapes.

It is a front view when the mold forming machine is fixed to the base. It is a perspective view of the mold molding machine. However, the injection device is omitted. (A) is a front view of a state in which the mold is in surface contact and the wedge member holds down the second block. However, the guide pillar is omitted. (B) is a front view of a state in which the piston rod is extended and the first block and the second block are separated. However, the guide pillar is omitted. It is a partial bottom view of the 2nd block and a mold clamping device.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 4.

As shown in FIGS. 1 and 2, the mold forming machine 1 is attached to the support base 100 via the mounting plate 1a, and has an injection device 2, a mold 3, a mold operating cylinder 30, and a mold clamping device 50. are doing.

The mold 3 has a first block 10 and a second block 20. The mold operation cylinder 30 is mounted on the first block 10 attached to the support base 100. The mold operation cylinder 30 projects vertically upward from the first block 10 (in the direction from the second block 20 to the first block 10), and has a piston rod 32 penetrating the first block 10. ing. The piston rod 32 is connected to the second block 20.

The injection device 2 is a device for injecting the molten plastic into the mold, and is detachably connected to the first block 10. The molten plastic produced by the injection device 2 is supplied to the cavity C via the supply hole 16 provided in the first block 10.

The guide pillar 35 projects vertically from the first block 10 downward (in the direction from the first block 10 to the second block 20) and penetrates the second block 20. The guide pillar 35 is for smoothly moving the second block 20 in the vertical direction.

The second block 20 is provided with a through hole (not shown) for allowing the guide pillar 35 to pass through. The outer diameter of the through hole is set to be slightly larger than the outer diameter of the guide pillar 35. Further, an ejector 25 is attached to the lower end of the second block 20.

The first contact surface 11 provided on the first block 10 and the second contact surface 21 provided on the second block 20 are rectangular shapes having the same shape in a plan view and are in surface contact with each other. Further, in the state of surface contact, the outer edges are aligned.

The mold clamping device 50 is for limiting the mutual movement between the first block 10 and the second block 20, and two of the mold clamping devices 50 are fixed to the side surfaces 15 and 15 of the first block 10, for a total of four. The number of the mold clamping devices 50 is not limited to this, and may be two in total, one on each side surface 15 on one side, or three or more on one side.

As shown in FIG. 3, the first block 10 is provided with a first cavity portion 12 that is detachably fixed, and the second block 20 is provided with a second cavity portion 22 that is detachably fixed. The first cavity portion 12 has a concave portion 12a, and the second cavity portion 22 has a convex portion 22a corresponding to the concave portion 12a. When the first contact surface 11 and the second contact surface 21 come into surface contact with each other, the concave portion 12a and the convex portion 22a cooperate to define the cavity C. The cavity C is a space for injecting molten plastic. A molded product is produced through a process in which the molten plastic produced by the injection device 2 is injected into the cavity C via the supply hole 16 provided in the first block 10.

As described above, by using the first cavity portion 12 and the second cavity portion 22 having different shapes of the concave portion 12a and the convex portion 22a, it is possible to easily produce molded products having different shapes with one mold molding machine. ..

The mold clamping device 50 has an accommodating portion 53, a wedge member 52, and a mold clamping cylinder 51. One end of the accommodating portion 53 is fixed to the first block 10 via a bolt. Further, at the other end, a storage hole 55 for housing the wedge member 52 is provided.

The wedge member 52 is defined with a first wedge surface 52a, a second wedge surface 52b, and a pair of wedge wall surfaces 58a, 58a. The first wedge surface 52a and the second wedge surface 52b are inclined toward the target at an angle of inclination α with respect to the axial direction L of the mold clamping cylinder 51 when viewed from the front. Further, the pair of wedge wall surfaces 58a and 58b extend in parallel along the axial direction L (see FIG. 4).

The accommodation hole 55 accommodates the wedge member 52, and the first accommodation surface 55a and the second accommodation surface (accommodation surface) 55b are defined at positions facing the first wedge surface 52a and the second wedge surface 52b. .. The first accommodating surface 55a and the second accommodating surface 55b are inclined toward the target at an angle of inclination angle α with respect to the axial direction L in the front view.

As shown in FIG. 4, the second block 20 is provided with a groove 17 in which the inclined surface 23 is defined. The inclined surface 23 is inclined at an angle of inclination α with respect to the axial direction L in the front view. As a result, when the wedge member 52 is extruded, the inclined surface 23 comes into surface contact with the first wedge surface 52a.

The inclination angle α is preferably 0 degrees to 45 degrees. Increasing the tilt angle α increases the rigidity of the wedge member 52. As a result, the displacement of the second block can be reduced when the molten plastic is injected into the cavity C. However, the inclined surface 23 and the first wedge surface 52a become slippery. Regarding the inclination angle α, 45 degrees is the limit angle at which the inclined surface 23 and the first wedge surface 52a do not slip. The inclination angle α may be appropriately determined in consideration of the shape and dimensions of the cavity C and the like.

The mold clamping and mold release of the mold forming machine 1 will be described.

In the state immediately before the mold clamping, the first block 10 and the second block 20 are in contact with each other under a predetermined pressure due to the operation of the mold operation cylinder 30. Specifically, the first contact surface 11 and the second contact surface 21 are in surface contact with each other under a predetermined pressure. Further, the wedge member 52 is accommodated in the accommodating hole 55.

The predetermined pressure is set smaller than the pressure generated in the cavity C. As a result, the mold operation cylinder 30 needs to have a lower capacity than the direct pressure type hydraulic cylinder.

The mold clamping cylinder 51 is operated to move the wedge members 52 provided opposite to each other in the direction of approaching each other (see FIG. 2). As a result, the wedge member 52 moves along the groove 17. Specifically, as shown in FIG. 4, the pair of groove wall surfaces 18a and 18b provided in the groove 17 and the pair of wedge wall surfaces 58a and 58b provided in the wedge member 52 move in contact with each other. As a result, lateral displacement between the first block 10 and the second block 20 can be avoided. With the movement, the inclined surface 23 and the first wedge surface 52a come into surface contact with each other, and the second wedge surface 52b comes into surface contact with the second accommodating surface 55b.

The movement of the wedge member 52 ends in a state where the inclined surface 23 and the first wedge surface 52a are in surface contact with each other and the second wedge surface 52b is in surface contact with the second accommodating surface 55b. At this time, the first contact surface 11 and the second contact surface 21 are maintained in a state in which at least a predetermined pressure is applied.

When the molten plastic is injected from the injection device 2, the molten plastic flows into the cavity C through the supply hole 16. At this time, a pressure exceeding a predetermined pressure is generated in the cavity C to try to separate the first block 10 and the second block 20. However, the wedge member 52 limits the movement of the second mold. Specifically, a force obtained by subtracting a force generated by a predetermined pressure from a force generated in the cavity C is supported by the second accommodating surface 55b via the inclined surface 23, the first wedge surface 52a, and the second wedge surface 52b. .. This limits the movement of the second block 20.

The molten plastic is injected into the cavity C, a pressure exceeding a predetermined pressure is generated in the cavity C, and an extremely small gap is generated between the first contact surface 11 and the second contact surface 21. However, since the molten plastic injected into the cavity C gradually begins to solidify from the outer peripheral portion of the cavity C, the molten plastic does not enter the minute gaps. As a result, burrs do not occur on the molded product.

It is preferable that the mold clamping device 50 is provided with a relative movement suppressing function of suppressing the relative movement of the first block 10 and the second block 20 below the gap that does not cause burrs in the molded product. This relative movement suppressing function is appropriately set in consideration of a predetermined pressure, the pressure generated in the cavity, the shape of the cavity C, the injection temperature of the molten plastic, and the like.

After cooling the molded product, the mold clamping cylinder 51 is operated to accommodate the wedge member 52 in the accommodating hole 55, and the mold operating cylinder 30 is operated to move the second block 20. As a result, the first block 10 and the second block 20 are separated. The ejector 25 is operated to project the molded product and take it out from the cavity C.

The mold clamping cylinder 51 may have the ability that the wedge member 52 does not displace when the molten plastic is injected into the cavity C, and that the wedge member 52 can be moved and accommodated in the accommodation hole 55 after the molten plastic is injected. preferable. This capacity may be lower than the capacity that the mold clamping cylinder used in the direct pressure type mold clamping device should have.

The support base 100 does not need to support the reaction force required to operate the mold clamping device 50 and the mold operation cylinder 30, and it is sufficient to support the own weight of the mold forming machine 1. Therefore, it can be made more compact than the support base used for the direct pressure type or toggle type injection molding machine.

This embodiment is an example, and it is needless to say that the present embodiment can be modified without departing from the technical idea of the present invention. For example, in the present embodiment, a so-called vertical mold forming machine in which the first block 10 and the second block 20 are laminated in the vertical direction is used, but the horizontal type in which the first block 10 and the second block 20 are arranged in the horizontal direction. It may be used as a mold forming machine. Further, although it is assumed that the inclination angles of the first wedge surface 52a and the second wedge surface 52b are the same, they may be different from each other. Further, the inclination angle of either one or both may be 0 degrees.

The mold forming machine of the present invention can make the apparatus itself compact. Therefore, the industrial applicability is great because the factory site can be used efficiently.

1: Mold forming machine 3: Mold 10: First block 17: Grooves 18a, 18b: Groove wall surface 20: Second block 23: Inclined surface 30: Mold operation cylinder 50: Mold clamping device 51: Mold clamping cylinder 52: Wedge member 52a: First wedge surface 52b: Second wedge surface 53: Accommodating portion 55b: Second accommodating surface (accommodation surface)
58a, 58b: Wedge wall surface C: Cavity L: Axial direction α: Tilt angle

Claims (4)

A mold having a first block including a first contact surface and a second block including a second contact surface and cooperating with the first block to define a cavity.
A type operating cylinder that changes the distance between the first block and the second block,
A mold clamping device fixed to each of the opposite side surfaces of the first block is provided.
The second block has an inclined surface defined by a groove provided on the surface facing the second contact surface.
The mold clamping device includes a wedge member that molds the mold by surface contact with the second block, an accommodating portion provided with an accommodating hole for accommodating the wedge member, and the wedge member. Has a mold clamping cylinder, which moves in the axial direction orthogonal to the side surface,
The wedge member has a first wedge surface extending along the axial direction and a second wedge surface facing the first wedge surface .
The accommodation surface is defined in the accommodation hole, and the accommodation surface is defined.
When the mold clamping device is operated in a state where the mold operation cylinder is operated and the first contact surface and the second contact surface are in surface contact with each other , the first wedge surface comes into surface contact with the inclined surface. At the same time, the mold forming machine is characterized in that the second wedge surface comes into surface contact with the accommodating surface to mold the mold. The mold forming machine according to claim 1 , wherein the first wedge surface and the second wedge surface have an inclination angle of 0 to 45 degrees with respect to the axial direction. The wedge member has a pair of wedge wall surfaces extending along the axial direction, and the groove includes the inclined surface corresponding to the first wedge surface and a pair of groove wall surfaces corresponding to the pair of wedge wall surfaces. The mold forming machine according to claim 1 or 2 , wherein the mold molding machine is characterized by having. The first block is provided with a first cavity portion that is detachably fixed, and the second block is provided with a second cavity portion that is detachably fixed, and the first cavity portion and the second cavity portion are provided. The mold forming machine according to any one of claims 1 to 3 , wherein the unit cooperates to define the cavity.

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