KR101909810B1 - Injection mold for molding products with thread - Google Patents

Abstract

The present invention relates to an injection molding die for molding a product, which has a screw portion enabling the injection molding product having a screw portion to be taken out by rotating the core shaft using a mold opening force without any separate driving means.
The present invention relates to a fixed side die plate (20) provided with a fixed side core (201) on one side and connected to a fixed side attachment plate (10) by a support pin (101); A runner stripper plate (30) provided between the fixed side attachment plate and the fixed side mold plate; A support plate 402 supported by a spacer block 401 provided on the movable-side attachment plate 40; A plate (50) provided with a shaft drive body (501) corresponding to the number of the fixed side cores and connected to the stationary side mold plate by a connecting rod (502); A movable-side template 60 provided with a movable-side core 601 corresponding to the number of fixed-side cores; A stripper plate (70) connected to the fixed side mold plate by a tension link (701); And a core shaft (80) having a screw core (801) which is rotatably supported by a bearing and is helically engaged with the shaft driving body, and has an inner end projecting from the center of each movable core.
According to the present invention, it is possible to reduce the mold production cost by simplifying the mold structure, improve the mold stability and durability, and significantly improve the productivity of the product by shortening the cycle time and fabricating the multi-cavity.

Description

Technical Field [0001] The present invention relates to an injection mold for injection molding,

The present invention relates to an injection mold for molding a product having a threaded portion, and more particularly, to an injection mold for molding a product having a threaded portion that allows the injection molding product having a threaded portion to be rotated by rotating the core shaft And an injection mold for molding a product.

'Injection molding' is a type of thermoplastics forming process. When the material heated in the cylinder is melted by using the properties of the thermoplastic plastic (even if it is heated in a molten state for curing and then cooled, When the molten resin is injected into the injection mold at a high pressure through the nozzle, the molten resin is filled in the cavity through the sprue, the runner and the gate. When the molten resin is cooled and solidified by the cooled mold, , And it is the most representative plastic molding method that enables mass production of plastic products by discharging molded products.

Meanwhile, the injection mold is formed with a molding space (hereinafter referred to as 'cavity') for molding the product therein. The molding cavity is divided into upper and lower cores or left and right cores The cores are made up of a set.

Accordingly, in order to mold the product, to separate the mold for discharging the product, and then to discharge the molded product from the cavity, a plurality of ejectors are disposed around the cavity so that the molded product is pushed out of the cavity of the mold, By installing the pin, the molded product is pushed out by using the ejector pin.

However, in the case of a product having a threaded portion among the injection-molded products, when the mold is separated in the process of separating the mold after the molding is completed, the spiral structure of the molded product engaged with the mold is damaged or collapsed In addition, since the product having the threaded portion can not be discharged from the cavity by the common ejector pin as described above, in the case of an injection mold for molding a product having a threaded portion, the injection mold itself is driven It is general that not only the device but also a separate rotating device for rotating the mold is provided.

1 is an exploded perspective view of an injection mold for plastic screw molding in which a pulley 2 driven by a belt 9, a worm 2 connected on the center axis of the pulley 2, A worm wheel 4 engaged with the worm 3, a flat difference 6 provided on a worm wheel shaft 5 extending vertically above the center of the worm wheel 4, A movable side core 12 fixed to the mold by a rotation preventing pin 11 is provided in a known driving device provided at the lower end of the movable member and composed of flat differentials 7 driven by meshing with the flat differential 6, And a plastic screw shaped article take-out device of the injection mold is disclosed.

Utility Model Public Affairs Office 1985-0000293 Utility Model Information Office 1989-0004617 Utility Model Public Affairs Office 1990-0007244

The above-described conventional technique is complicated in the structure of the injection mold, and the injection process itself is complicated, so that the time required for the process is delayed and the productivity is lowered. In addition, There were frequent disadvantages.

Further, since it is difficult to form the front, rear, left and right sides of the mold structurally in a well-balanced manner, the stability of the mold is low and the durability of the mold is thereby deteriorated.

In addition, since the gate is limited, it is difficult to apply the pin point gate, so that the separation between the runner and the product is difficult, so that the secondary sorting operation is required and the productivity is lowered.

In addition, when the mold is opened and closed, the operating oil is dropped on the product due to the exposure of the worm shaft, and the product is frequently contaminated, thereby increasing the defective product rate.

Further, in the prior art, when the number of worm shafts is increased for the purpose of producing a large number of products, all the gears engaged with the worm shafts operate in an interlocked manner, so that even if only one component is broken, There are disadvantages.

In order to overcome the above-mentioned problems, the injection-molded injection mold for a product having a threaded portion of the present invention is provided with a fixed-side core 201 on one side thereof, A fixed-side template 20 connected to the fixed-side template 20;

A runner stripper plate (30) provided between the fixed side attachment plate (10) and the fixed side mold plate (20);

A support plate 402 supported by a spacer block 401 provided on the movable-side attachment plate 40;

A shaft driving body 501 corresponding to the number of the fixed side cores 201 is provided on the outer side surface of the movable side attachment plate 40 and the support plate 402, A plate 50 connected to the side plate 20;

A movable side mold plate 60 provided inside the support plate 402 and provided at one side thereof with a movable side core 601 corresponding to the number of the fixed side cores 201;

A stripper plate 70 installed between the fixed side mold plate 20 and the movable side mold plate 60 and connected to the fixed side mold plate 20 by a tension link 701;

And is rotatably supported by bearings provided on the movable side attachment plate 40 and the support plate 402 so as to be coupled to the shaft drive body 501. The inside end portion of the movable side core 601 And a core shaft 80 provided with a threaded core 801 for mounting the threadable member.

According to the injection mold for molding a product having a threaded portion of the present invention, the core shaft is rotated using a mold opening force without a separate driving means through the above-described structure, and the injection molding product having a threaded portion can be taken out. It is possible to simplify the mold production cost and to improve the mold stability and durability, and to achieve the object of greatly improving the productivity of the product through the reduction of the cycle time and the production of the multi cavity.

In the injection mold for molding a product having the threaded portion of the present invention, there is no need for a separate driving means for driving the core shaft provided for each cavity, and the core shaft is rotated using the mold opening force, Since the injection-molded product can be taken out, it is possible to reduce the volume of the mold, thereby remarkably reducing the production cost of the mold.

In addition, since the core shaft is not exposed to the outside, it is possible to prevent contamination of the injection product due to external exposure of the lubricant for smooth rotation of the core shaft. There is an effect that can be.

In addition, the one cycle time for injection molding of the product is greatly shortened, and it can be applied to multi-cavity screw molds, which can greatly improve the productivity of the product, and the mold can be designed and manufactured in a balanced manner, The durability life of the mold can be greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a conventional art relating to an injection mold for molding a product having a threaded portion. Fig.
2 is a cross-sectional assembled view of an embodiment of an injection mold for molding a product having threaded portions of the present invention.
3 is an assembled cross-sectional view of an assembled working distance limiting structure according to an embodiment of an injection mold for molding a product with threads of the present invention.
4 is a cross-sectional view of an injection mold according to an embodiment of the present invention;
5 is a perspective view showing a coupling structure of a shaft driving body and a core shaft according to an embodiment of an injection mold for molding a product having a threaded portion of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the structure and operation of an injection mold for molding a product having a threaded portion according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 2 to 5, the injection molding die for molding a product having the threaded portion of the present invention is provided with a fixed-side core 201 on one side thereof, and is fixed to the fixed-side attachment plate 10 with a support pin 101 A side plate (20); A runner stripper plate (30) provided between the fixed side attachment plate (10) and the fixed side mold plate (20); A support plate 402 supported by a spacer block 401 provided on the movable-side attachment plate 40; A plate 50 provided with a shaft driving body 501 corresponding to the number of the fixed-side cores 201 and connected to the fixed-side plate 20 by a connecting rod 502; A movable side die plate 60 provided with a movable side core 601 corresponding to the number of the fixed side cores 201; A stripper plate (70) connected to the stationary side template (20) by a tension link (701); A core shaft 80 having a threaded core 801 rotatably supported by bearings and helically engaged with the shaft drive body 501 and having an inner end projecting from the center of each movable core 601, .

The fixed side attachment plate 10 has a sprue bushing 102 for discharging the molten resin in the injection molding machine so that the molten resin of the injection molding machine is injected into the cavity as is well known.

Although the fixed-side attachment plate 10 is located on the right side in the figure, it is of course possible to arrange it on the upper side of the injection molding machine if necessary.

A plurality of fixed-side cores (201) for product molding are formed on one side of the fixed-side template (20), and a plurality of fixed-side cores (201) It is preferable to form the runner so that it can be supplied quickly and uniformly.

The support pin 101, which is fixed at one end to the fixed-side attachment plate 10, penetrates through the fixed-side template 20 so as to be precisely and stably opened and closed when the mold is opened and closed, As shown in Fig.

The runner stripper plate 30 is installed between the fixed side attachment plate 10 and the fixed side mold plate 20 so that the molten resin discharged from the sprue bushing is fixed The support pins 101 are passed through the runners formed on one side of the side plate 20 so that the runner can be easily cooled and solidified together with the product during the mold cooling process. Therefore, it slides.

The support plate 402 is fixed to the spacer block 401 provided on the movable plate 40 and is spaced apart from the movable plate 40 by a predetermined distance. Through which the other end of the support pin 101 having one end fixed to the side attachment plate 10 passes and the through hole through which the connection rod 502 connecting the stationary side template 20 and the plate 50 passes .

In addition, bearings for rotatably supporting the core shaft 80 are preferably provided on the inner and outer surfaces of the support plate 402.

The plate 50 is installed between the movable side attachment plate 40 and the support plate 402 and the shaft drive body 501 corresponding to the number of the fixed side cores 201 is provided on the outer side, Side mold (502).

Preferably, the shaft driving body 501 is spirally engaged with the core shaft 80 so as to rotate the core shaft 80 by using the mold opening force during the mold opening process.

Therefore, even when the position of the plate 50 connected to the stationary-side plate 20 by the connecting rod 502 is fixed during the retraction of the movable-side mounting plate 40 during die opening, The core shaft 80 provided at one end to the movable attachment plate 40 is rotated by the spiral engagement with the shaft drive body 501 so that the external force of the motor, It is possible to take out the injection-molded product having the above-mentioned shape.

The movable side mold plate 60 is installed so as to be spaced apart from the support plate 402 by using a template bolt 602 screwed to the support plate 402 so as to be located inside the support plate 402, A spring 603 is provided between the movable side mold plate 60 and the movable mold side mold 60 so that the support pin 101 and the connecting rod 502 pass through. The movable core 601 is provided.

The movable core (601) has a mutual contact surface with the fixed core (201) and forms a cavity, which is a molding space for molding the product when assembled.

Therefore, the shape of the cavity is determined by the inner shape of the fixed-side core 201 and the movable-side core 601, and the fixed-side core 201 and the movable-side core 601 are used for molding an injection- A threaded portion is formed in the movable core 601 for injection molding a cap-shaped product having a female screw portion formed therein.

The stripper plate 70 is spaced apart from the support plate 402 by a stripper bolt 702 screwed to the support plate 402 so as to be positioned between the fixed side plate 20 and the movable side template 60 The support pin 101 and the connecting rod 502 are connected to each other by a tension link 701 through a connection part of the fixed side mold plate 20 by providing a through hole so as to penetrate the support pin 101 and the connecting rod 502.

The tension link 701 forms a long hole 701a in the mold opening and closing direction so that the stripper plate 70 moves along the connecting rod 502 when assembled so that the inner surface of the stripper plate 70 contacts the fixed side plate 20, and the outer side surface of the stripper plate 70 is in close contact with the inner side surface of the movable side template 60.

When the movable die plate 60 is retracted, the retraction distance is limited by the template bolts 602 and the movable die plate 60 and the stripper plate 70 are pressed against the tension link 701 At this time, the stripper bolts 702 limit the separation distance so that the injection-molded product molded by the movable-side core 601 of the movable-side template 60 is discharged.

The core shaft 80 is rotatably supported by a bearing installed on the movable attachment plate 40 and the support plate 402. The outer end of the core shaft 80 is fixed to the support plate 402, And a threaded core 801 provided so as to be rotatable at the center of each movable core 601 is engaged with the shaft drive body 501 provided on the plate 50 to thereby rotate the shaft drive body 501) to rotate without any external power supply.

The core shaft 80 uses a four-row screw type worm shaft for smooth rotation and directional crystallization of the core shaft 80 using the die opening force, but it is not limited to this.

The threaded core 801 forms a threaded portion of the product when the product is molded in the cavity, and a male thread is formed on the outer circumferential surface thereof to form a female threaded portion in the product when the product is molded in the cavity.

Needless to say, the screw core 801 can be disassembled and assembled at the inner end of the core shaft 80, and the shape, size, spacing and the like of the screw formed in the screw core 801 can be changed according to the design of the product to be injection- .

Hereinafter, the operation of the injection mold for molding a product having the threaded portion to which the technique of the present invention is applied will be described.

When the molten resin is supplied into the cavities formed by the fixed-side core 201 and the movable-side core 601 in a state where the molds are all closed as shown in FIGS. 2 to 3, The screw core 801 performs injection molding of a product having a threaded portion inside the cavity.

After the product molding is completed, when the mold is opened while the movable side attachment plate 40 is retracted for taking out the product as shown in FIG. 4, the fixed side mold plate 20 is first separated from the runner stripper plate 30, The runner stripper plate 30 is separated from the stationary-side mold plate 20 so that the molten resin can be quickly and uniformly supplied to the stationary-side core 201 of the stationary- ). ≪ / RTI >

After the fixed side mold plate 20 and the runner stripper plate 30 are separated from each other, as the mold opening continues, the fixed side mold plate 20 is retracted by a predetermined distance and then stopped at the support pin 101 When the mold opening continues even in the state where the fixed side mold plate 20 is stopped, the core shaft (not shown) which is helically engaged with the shaft drive body 501 of the plate 50 connected to the fixed side mold plate 20 by the connecting rod 502 80 are rotated by the mold opening force.

That is, since the core shaft 80 is helically engaged with the shaft drive body 501 fixed to the plate 50, when the movable side attachment plate 40 moves backward when the die is released, the shaft drive body 501 The threaded core 801 provided at the inner end of the core shaft 80 is rotated by rotating the core shaft 80 by the spiral engagement of the core shaft 80. [

Since the inner end of the product is in close contact with the inner end of the movable core 601 at the time of molding the product in the cavity, the thread core of the product P, together with the core shaft 80, 801 rotate, the product having the threaded portion is released from the threaded core 801.

The movable side template 60 is separated from the base plate 402 by the elastic force of the spring 603 provided between the base plate 402 and the movable side template 60 and the tension link 701 The stripper plate 70 connected to the movable side mold 60 is spaced apart from the movable side mold plate 60 so that the product P having the threaded portion injection molded from the movable side core 601 can be taken out smoothly.

As described above, in the injection mold for molding a product having the threaded portion of the present invention, no separate driving means is required for driving the core shaft 80 provided for each cavity, and the core shaft 80 is rotated It is possible to take out an injection-molded product having a threaded portion formed in a cavity, so that it is possible to reduce the volume of the mold by simplifying the mold structure, thereby remarkably reducing the production cost of the mold, The durability of the mold is excellent, and it is possible to be applied to various sizes of molds from small size to large size.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

10: fixed side attachment plate 101: support pin
20: fixed side mold plate 201: fixed side core
30: runner stripper plate 40: movable side attachment plate
401: spacer block 402:
50: Plate 501: Shaft drive body
502: connecting rod 60: movable side template
601: movable core 70: stripper plate
701: Tension link 80: Core shaft
801: Thread core

Claims (1)

A stationary-side template 20 provided with a stationary-side core 201 on one side and connected to the stationary-side attachment plate 10 by a support pin 101;
A support plate 402 supported by a spacer block 401 provided on the movable-side attachment plate 40;
A movable side mold plate 60 provided inside the support plate 402 and provided at one side thereof with a movable side core 601 corresponding to the number of the fixed side cores 201;
A stripper plate 70 installed between the fixed side mold plate 20 and the movable side mold plate 60 and connected to the fixed side mold plate 20 by a tension link 701;
And is rotatably supported by bearings provided on the movable side attachment plate 40 and the support plate 402 so as to be coupled to the shaft drive body 501. The inner side end portion is connected to the center of each movable side core 601 And a core shaft (80) provided with a threaded core (801) for installing a projection member;
A runner stripper plate (30) provided between the fixed side attachment plate (10) and the fixed side mold plate (20);
The shaft driving body 501 corresponding to the number of the fixed side cores 201 is provided on the outer side of the movable side attachment plate 40 and the support plate 402, Further comprising a plate (50) connecting with the stationary side template (20);
Wherein the core shaft (80) is a worm shaft of a four-row screw type for smooth rotation and directional crystallization of the core shaft (80) using the mold opening force.

Images