JPS6350175B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a die-cutting device for cutting out molded products such as spiral gears and screws in, for example, plastic injection molding machines.

Prior Art In a plastic injection molding machine, as shown in FIG. A mold clamping cylinder 3 that operates the movable die plate 5 to open and close the mold 8 and the mold 8, and a cavity S in the molds 7 and 8 that are closed as shown in FIG.
If the core 9 in the molds 7 and 8 is not rotated along the helix angle of the spiral gear or the lead angle of the screw, like a spiral gear or screw, If the molded product cannot be removed, a special molded product punching device is required. In the conventional molded product punching device, a rack 19 operated by a core rotation cylinder 18 installed at the top of the movable mold 8 is inserted into the movable mold 8 and fitted onto the core 9. Each extrusion pin 1 of the extrusion device 12 shown in FIG. 6 is meshed with the pinion 16.
2a was inserted into the core 9. After opening the mold, the core 9 is rotated via the pinion 16 by the movement of the rack 19, and the molded product is extruded from the cavity S together with the core 9. Thereafter, the molded product is separated from the core 9 by the extrusion pin 12a. It was starting to look like this.

In this structure, the core rotation mechanism, that is, the core rotation cylinder 18, the rack 19, and the pinion 16 are directly attached to the movable mold 8, and the rack 19 and pinion 16 are inside the movable mold 8, so that they are not deflected. As a result, the dimensions of the molds 7 and 8 become larger compared to the dimensions of the molded product, increasing the cost of the molds and, in turn, increasing the dimensions of the fixed and movable die plates 2 and 5. However, the disadvantage was that the entire injection molding machine became larger and its cost increased. Furthermore, it is necessary to install a core rotation cylinder 18 for each mold 7, 8.
When replacing the molds 7 and 8, work such as connecting piping to the core rotating cylinder 18 is required, which not only reduces work efficiency but also increases the manufacturing cost of the molds 7 and 8.

Purpose The purpose of the present invention is to miniaturize the mold and reduce the manufacturing cost of the mold by providing a core rotation mechanism required when molding spiral gears, screws, etc. at a predetermined position outside the movable mold. To provide a molded product punching device for an injection molding machine, etc., which can reduce the manufacturing cost of the mold clamping device by reducing the size of the mold clamping device, and improve work efficiency when changing molds. be.

Structure of the Invention In order to achieve this object, the present invention has a core installed on the outer surface of the movable die plate, that is, on the opposite side of the mounting side of the movable die, to the shaft that rotates the core incorporated in the movable die. This is a system in which a child rotation mechanism is linked.

Embodiment Hereinafter, an embodiment in which the present invention is applied to a plastic injection molding machine will be described with reference to FIGS. 1 to 5. A mold clamping cylinder 3 is fixed to each part, and a movable die plate 5 is fixed to the tip of a diver 4 (the rod of the mold clamping cylinder 3 is used as a dieper) operated by the mold clamping cylinder 3. The movable die plate 5 moves on the machine base 1 as the diver 4 advances and retreats as the cylinder 3 operates. A fixed mold 7 is attached to the inner surface of the fixed die plate 2, and a movable die 8 is attached to the inner surface of the movable die plate 5. Both dies 7 and 8 move as the movable die plate 5 moves. The molds are designed to open and close with each other. Further, a heating cylinder 6 for supplying molten resin is provided on the outside of the fixed die plate 2 so as to be movable forward and backward.

A core 9 is supported in the movable mold 8 so as to be rotatable and movable in the front and rear directions, and the upper and lower sides of the movable mold 8 are connected to two spiral grooves 10 formed on the outer peripheral surface of the core 9. A fixing pin 11 fixed to the section is engaged. Note that this spiral groove 10 and fixing pin 11
A cam mechanism is constructed. A molded product extrusion member 12 is incorporated into the core 9 so as to be movable in the front-rear direction, and each extrusion pin 12a thereof is inserted through the core 9. This pushing member 12 is always urged in the direction of arrow A by a spring 13.

A support member 14 is attached to the outer surface of the movable die plate 5, that is, the opposite side to the attachment side of the movable die 8, and a pinion 16 is attached to the inner ring 14a of the support member 14 via a rotary cylinder 15 so as to be able to rotate integrally with the support member 14. . This rotary cylinder 15 has a spline shaft 17.
are fitted so as to be rotatable together and movable in the axial direction, and a cylindrical portion 9a on the rear side of the core 9 in the movable die plate 5 is fitted to the inner end of the spline shaft 17 so as to be rotatable together and movable in the axial direction. It is fitted so as to be movable in the axial direction of the spline shaft 17. The inner end of this spline shaft 17 is adapted to come into contact with the extrusion member 12.
A core rotating cylinder 18 is installed above the movable die plate 5, and a rack 19 that is moved up and down by the cylinder 18 is engaged with the pinion 16 as shown in FIG. The pinion 16, core rotation cylinder 18, and rack 19 constitute a core rotation mechanism.

As shown in FIGS. 1 and 2, a molded product extrusion cylinder 20 is attached to the outer surface of the movable die plate 5 in conjunction with the support member 14, and a connecting plate 21 is fixed to the cylinder rod 20a. .
As shown in FIG. 3, a threaded rod 22 fixed to the outer end of the spline shaft 17 passes through one end of the connecting plate 21. As shown in FIG. The spline shaft 17 is always urged in the direction of arrow B via the screw rod 22 by a spring 23 supported by the connecting plate 21 in the retreated position, and moves forward and backward as the connecting plate 21 moves forward and backward.

Next, the operation of the molded product punching device configured as above will be explained.

In the state shown in FIG. 3, the mold 7 is closed,
The resin is injected from the heating cylinder 6 into the cavity S in the heating cylinder 8 and filled with the resin, and the connecting plate 21 is in the retracted position, and the extrusion member 12 and the spline shaft 17 are in the retracted position due to the urging force of the springs 13 and 23. Immediately after the molds 7 and 8 are opened from this state, the core rotation cylinder 18 is activated and the rack 1 is opened.
9 rotates the pinion 16. This rotation of the pinion 16 is transmitted to the spline shaft 17 via the rotary cylinder 15, and the core 9 also rotates due to the rotation. Then, a spiral groove 10 on the outer peripheral surface of the core 9
Since the core 9 is engaged with the fixing pin 11, the core 9 rotates and moves forward along the spline shaft 17, and due to the rotation and advancement, the molded product also rotates and moves forward. Thereafter, the molded product extrusion cylinder 20 is activated and the connecting plate 21 moves forward as shown in FIG. As the spline shaft 17 advances, the spline shaft 17 comes into contact with the molded product extrusion member 12, and then moves the extrusion member 12 forward against the bias of the spring 13. By this movement, each extrusion pin 12a pushes out the molded product, and the molded product is die-cut. After the die is removed, the connecting plate 21 is retracted, and the spline shaft 17 is accordingly retracted.
Further, the molded product extrusion member 12 is moved backward due to the urging force of the spring 13. Thereafter, the pinion 16 rotates in the opposite direction, and the core 9 moves backward while rotating in the opposite direction.

In the above embodiment, the core 9 moves forward or backward while rotating, and the extrusion function of the molded product is performed by the extrusion member 1.
However, the core 9 may only be rotatable and the molded product may be extruded only by the extrusion member 12. It is also possible to repeat extrusion of the molded product several times.

Effects According to the present invention described in detail above, the core rotation mechanism required when molding spiral gears, screws, etc. is provided at a predetermined position outside the movable mold 8 as described above. , 8 to reduce the manufacturing cost of the molds 7 and 8, which in turn reduces the size of the mold clamping device 3 to reduce the manufacturing cost of the mold clamping device 3, and reduces the work required when replacing the molds 7 and 8. This has the effect of improving efficiency.

[Brief explanation of drawings]

Figures 1 to 5 show an embodiment of the present invention, with Figure 1 being a partially cutaway front view showing the mold clamping mechanism of a plastic injection molding machine, and Figure 2 showing the outer surface of the movable die plate. 3 is a partial cross-sectional view showing the molded product punching device when the mold is closed, FIG. 4 is a side view showing the inner surface of the movable mold after the mold is opened and before the molded product is extruded, and FIG. 5 is the molding A sectional view taken along the line X--X in FIG. 4 showing the molded product die cutting device after extrusion of the product,
7 and 7 show a conventional example, FIG. 6 is a front view showing a mold clamping mechanism of a plastic injection molding machine, and FIG. 7 is a partial sectional view showing a molded product punching device when the mold is closed. Fixed die plate...2, mold clamping cylinder (mold clamping device)...3, movable die plate...5, heating tube (molten material supply device)...6, fixed mold...7, movable mold...
8, Core…9, Spiral groove…10, Fixing pin…11,
Molded product extrusion member...12, spring...13, pinion...16, spline shaft...17, core rotation cylinder...18, rack...19, molded product extrusion cylinder...20, spring...23.

Claims (1)

[Claims] 1 Fixed die plate 2 and movable die plate 5
and a mold clamping device 3 that operates the movable die plate 5 to open and close the fixed mold 7 attached to the fixed die plate 2 and the movable die 8 attached to the movable die plate 5, and the above-mentioned when closing the mold. In a molding machine equipped with a molten material supply device 6 that fills cavities S in the molds 7 and 8 with a material such as resin, a shaft 17 that rotates a core 9 incorporated in the movable mold 8 is provided. , the movable die plate 5
A molded product punching device for an injection molding machine or the like, characterized in that core rotation mechanisms 16, 18, and 19 mounted on the outer surface side of the movable mold 8, that is, on the opposite side to the mounting side of the movable mold 8, are linked. 2 The shaft 17 is a spline shaft, and the core 9 is fitted to the spline shaft 17 so as to be able to rotate integrally therewith and to be movable in the axial direction thereof. cam mechanism 1 for moving the core 9 in the axial direction of the spline shaft 17
A molded product die cutting device for an injection molding machine or the like according to claim 1, which is provided with 0.0 and 11. 3. The cam mechanisms 10, 11 include a spiral groove 10 formed on the outer circumferential surface of the core 9, and a fixing pin 11 that engages with the spiral groove 10. Molded product punching device. 4 Core rotation mechanisms 16, 18, 19 are shaft 1
A pinion 16 is fitted to the pinion 7 so as to be able to rotate integrally with the pinion 7.
And the rack 19 meshed with this pinion 16
A molded product die cutting device for an injection molding machine or the like according to claim 1, comprising a core rotating cylinder 18 for operating the rack 19.