KR19990023723U - Undercut Molding Machine for Injection Mold - Google Patents

Abstract

The present invention relates to an undercut molding apparatus of an injection mold, and includes a fixed side mold plate 20 having a receiving space 24 at a predetermined position facing the runner stripper plate 30 and a receiving space of the fixed side mold plate 20. The slider 100 accommodated in the 24 and moved up and down, and provided in the slider 100 enters or is spaced apart from the cavity 22 of the fixed side plate 20 according to the vertical movement of the slider 100. The core pin 140 for forming the undercut and the runner stripper plate 30 to press the slider 100 at the same time as the closed side of the fixed side plate 20 to enter the core pin 140 to enter the cavity 22. The pressing member 200 and the elastic member 160 for supporting the slider 100 so as to space the core pin 140 from the cavity 22 in response to the pressing force of the pressing member 200 as a characteristic configuration, Installed on the runner stripper plate in the process of closing the injection mold One pressing member provides movable force to the slider provided on the fixed side plate, so that the core pin forms the undercut of the inclined surface of the injection molding without any additional process, and at the same time, the core pin is removed during the process of reforming the mold. As the number of separate processes for the reduction is reduced, the workability of the injection process is improved and the cost is reduced.

Description

Undercut Molding Machine for Injection Mold

The present invention relates to an injection mold, and more particularly, to an undercut molding apparatus of an injection mold for molding a shape in an oblique direction from the outside of the injection molding.

In general, an injection mold is a device that fills and solidifies a molten resin in a molding space provided inside a mold, and then ejects it to form a desired injection molding. The movable side is opened or closed by a vertical operation on a fixed side to form an injection molded product. By removing the structural limitations of the two-stage mold method and the two-stage mold method, the gate position is relatively free and the runner and sprue are removed in the open state so that the molding distortion and deformation of the injection molding are small. There is a type.

The injection mold is configured to be ejected after molding the injection molding by the vertical operation method, the shape provided in the transverse direction on the inside and outside of the injection molding, that is, the groove and the hole is formed with an undercut molding apparatus which is a separate mechanism.

In Figure 1, the three-stage injection mold is fixed side plate 20 and the runner stripper plate 30 is fixed on the fixed side mounting plate 10 having a molten resin inlet (not shown), the fixed side mounting plate ( The angular cam 50 provided in 10 enters the locking block 60 provided in the fixed side plate 20 and slides the locking block 60 to enter the slide core 70. The core core 80 is provided with a slide core 70 supported by the elastic member 90 is a cavity (core) 80 is provided on the fixed side plate 20 with the elastic member 90 contracted ( 22) is protruded to a predetermined range, that is, the slide to the position to enter the injection molding to form a hole. Then, the movable side plate 40 having the core 42 is joined to the fixed side plate 20 so that the injection mold is closed.

When the molten resin of the high temperature and high pressure state filled with the cavity 22 through the injection hole in the above state is molded by the cavity 22, the core 42, and the core pin 80 with outward, inward and undercut, The movable side plate 40, the fixed side plate 20, and the runner stripper plate 30 are sequentially opened to take out the injection molded product.

When the fixed side plate 20 is opened in the fixed side mounting plate 10 as described above, the angular cam 50 is separated from the locking block 70. Then, when the locking block 70 slides away from the slide core 70, the elastic force of the elastic member 90 is released while expanding and the slide core 70 is pushed upward while the core pin 80 is pushed in the cavity 22. It is configured to be spaced apart from a predetermined range.

However, the conventional injection mold is an angular cam 50 by applying an indirect supporting method in which the slide core 70 having the core pin 80 for molding the undercut to the injection molding is supported through the locking block 70. And it is difficult to select the rocking block 70 and the slide core 70 and the exact position is difficult when the car is released, the slide core 70 is pushed against the injection pressure, there was a problem that injection failure occurs.

Another problem is that the number of processes is increased by using a plurality of parts such as the angular cam 50 and the locking block 60 in the process of forming the undercut inside the injection molding, thereby increasing the cost of the injection molding product and delaying the manufacturing process.

The present invention has been made to solve the above problems, an object of the present invention is to provide an undercut molding apparatus of an injection mold that is ejected at the same time the undercut is molded on the inner surface of the injection molding by the opening or closing operation of the mold. have.

Another object of the present invention is to provide an undercut molding apparatus for an injection mold in which a rigid number of the undercut molding machine is ensured by the opening or closing of a mold, and the number of parts is simplified.

The present invention for realizing the above object is a fixed side core having a cavity is opened or closed to a fixed side mounting plate having an injection hole through a runner stripper plate, while the movable side plate having a core is fixed side mounting plate. An injection mold in which a molten resin injected through an injection hole is formed into an open or closed shape to form an inward and an outward direction of an injection product by a cavity and a core, the fixed side plate having a receiving space at a predetermined position facing the runner stripper plate. And a slider which is accommodated in a receiving space of the fixed side plate and moved up and down, a core pin which is provided in the slider and enters or is spaced apart from the cavity of the fixed side plate according to the vertical movement of the slider to form an undercut in the injection molding, and a core pin. To press the slider at the same time as the closed side of the fixed side plate to enter the cavity The pressing member provided on the tripper plate and an elastic member for supporting the slider so as to space the core pin from the cavity in response to the release of the pressing force of the pressing member, the slider and the receiving space according to the pressing of the pressing member It is set as the structure provided with the shock absorbing member which moderates the impact with the bottom face.

1 is a front sectional view showing the configuration of an injection mold to which the undercut molding apparatus of the prior art is applied;

2 and 3 is a view showing the configuration and operating state of the injection mold applying the undercut molding apparatus of the present invention,

Figure 2 (a) is a front sectional view showing the configuration of the undercut molding apparatus in the closed state,

Figure 2 (b) is a side cross-sectional view showing the configuration of the undercut molding apparatus applied to Figure 2 (a),

3 (a) is a sectional front view showing the configuration of the undercut molding apparatus in the open state;

Figure 3 (b) is a side cross-sectional view showing the configuration of the undercut molding apparatus applied to Figure 3 (a).

* Explanation of symbols for main parts of the drawings

10: fixed side mounting plate 20: fixed side plate

22: cavity 24: accommodation space

30: runner stripper plate 100: slider

140: core pin 160: elastic member

200: pressing member 300: buffer member

Hereinafter, with reference to Figures 2 and 3 attached to an embodiment of the present invention in detail as follows.

In the drawings, reference numeral 20 denotes a fixed side plate having a cavity 22, and the lower side of the runner stripper plate 30 mounted on the fixed side plate 20 so as to be opened or closed on the fixed side mounting plate 10. The accommodating space 24 is formed in a predetermined predetermined position.

The accommodating space 24 includes a slider 100 that is free to elevate a predetermined range by an external force. Slider 100 has a core pin 140 to enter the cavity 22 on both sides of the lower end to form an undercut in the injection molding, the elastic to elastically support the slider 100 to the receiving surface 24 as a support surface The member 160 is provided at a position adjacent to the core pin 140 and at the same time, the slider 100 is prevented from protruding into the accommodation space 24 by the expansion of the elastic member 160. A bolt 420 is fastened to an outer circumference to install a fixing member 400 supporting the upper end of the slider 100. In addition, the elastic member 160 is recessed in the recess shape formed in the bottom surface of the receiving space 24 in the state in which the elastic groove 120 formed at the lower end of the slider 100 for stable support ( 26).

In addition, the lower end of the slider 100 is provided with a buffer member 300 to mitigate the impact of the slider 100 and the receiving space 24 to be lowered by the external force to increase the durability of the mold. The shock absorbing member 300 is a urethane material, but is not limited thereto. The shock absorbing member 300 is fastened to the lower end of the slider 100 by the fastening bolt 320 provided in the molding process, and the lower end is accommodated against the lower end of the slider 100. It is provided so as to protrude to the bottom face side of the space 24.

Reference numeral 30 denotes a runner stripper plate which is opened or closed at the lower end of the fixed side mounting plate 10 having an injection hole (not shown), and the lower side of the runner stripper plate 30 is attached to the fixed side plate 20. The pressing member 200 according to the present invention for pressing the received slider 100 is configured by fastening with a bolt 240.

The pressing member 200 has two pressing surfaces 220 having a lower end on both sides of the opening side making contact with the slider 100 in a state where the opening side is downward in a channel shape.

Reference numeral 40 denotes a normal movable side plate provided with a core 42.

Referring to the operation of the present invention by the above configuration as follows.

First, in the present invention in FIG. 2, the injection mold is closed, that is, the runner stripper plate 30 and the fixed side plate 20 are joined to the fixed side plate 30, and the core 42 of the movable side plate 40 is formed. After entering the cavity 22 of the stationary side plate 20, the molten resin injected through the injection port (not shown) provided in the stationary side plate 30 is filled in the cavity 22 to be molded into an injection molded product.

In this state, the pressing surface 220 of the pressing member 200 provided in the runner stripper plate 30 presses the upper end of the slider 100 accommodated in the fixed side plate 20. As the slider 100 slides downward from the receiving space 24, the core pin 140 provided at the bottom of the slider 100 enters the cavity 22 without additional processing to form an undercut on the inclined surface of the injection molding. Is placed in the position.

At this time, the elastic member 160 is contracted and at the same time the buffer member 300 provided at the bottom of the slider 100 makes contact with the bottom surface of the accommodation space 24 of the fixed side plate 20, while the bottom of the slider 100 and the accommodation space To mitigate the impact of collision with (24).

After the molding of the injection molding having the undercut in the cavity 22 is completed, when the injection mold is opened to take out the injection, that is, the fixed side plate 20 and the runner stripper plate 30 are fixed to the side as shown in FIG. 3. When the plate 10 is remodeled, the pressing member 200 and the slider 100 are spaced apart. At this time, the contracted elastic member 160 is expanded and at the same time the slider 100 is shot and slides to the opposite side of the cavity 22. Accordingly, the core pin 140 provided on the slider 100 rises like the slider 100 and exits from the undercut formed on the inclined surface of the sand without any additional process.

Meanwhile, in the embodiment of the present invention, the elastic member 160 and the core pin 140 are provided at two places, and the pressing member 200 has two pressing surfaces 220 at the two places. The present invention is not limited thereto, and the technical idea of the present invention may be realized in which the undercut is formed in the mold opening or closing process without additional processing.

The present invention provides the movable force to the slider provided on the fixed side plate by the pressing member installed on the runner stripper plate in the process of closing the injection mold, so that the core pin forms the undercut of the inclined surface of the injection molding without any additional process. By removing the core pin during the reforming process, the number of separate processes for the undercut molding is reduced, thereby improving the workability of the injection process and reducing the cost.

In addition, the support of the core pin by the pressing portion pressing the slider ensures a firm fixing of the core pin by the direct support method has the effect of improving the quality of the injection molding.

In addition, by stabilizing the pressure transmitted to the slider, the durability of the mold is improved, the effect of improving the reliability mechanically, such as the surface extension of the injection mold.

Claims (2)

The fixed side core with the cavity is opened or closed in a predetermined range to the fixed side mounting plate with the inlet through the runner stripper plate, and the movable side plate with the core is open or closed with the fixed side mounting plate. In the injection mold in which the injected molten resin is molded inward and outward by the cavity and the core, A fixed side plate 20 having a receiving space 24 at a predetermined position facing the runner stripper plate 30, and a slider housed in the receiving space 24 of the fixed side plate 20 and moved up and down ( 100 and a core pin 140 provided in the slider 100 to enter or be spaced apart from the cavity 22 of the fixed side plate 20 in accordance with the vertical movement of the slider 100 to form an undercut in the injection molding, and a core. The pressing member 200 provided in the runner stripper plate 30 and the pressing member 200 to press the slider 100 simultaneously with the closed shape of the fixed side plate 20 to enter the pin 140 into the cavity 22. Undercut molding apparatus for injection mold, characterized in that consisting of an elastic member 160 for supporting the slider 100 so as to space the core pin 140 in the cavity 22 in accordance with the release of the pressing force. The method of claim 1, wherein the slider 100 is characterized in that the configuration provided with a buffer member 300 to mitigate the impact of the slider 100 and the bottom of the receiving space 24 due to the pressing of the pressing member 200. Undercut molding apparatus of injection mold.