JPH0530169B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an injection molding apparatus, and includes an extrusion plate that is moved to peel off an injection molded product from a movable insert of an injection mold, and an extrusion plate that is moved to peel off an injection molded product from a movable insert of an injection mold. This relates to a detachable connection structure with a driven extrusion rod.

[Prior art]

FIG. 7 is a sectional view showing an example of the prior art.
An injection mold 1 is mounted between die plates 2 and 3 of an injection molding apparatus. One die plate 3 is formed to be movable using rods 4 and 5 as guides, and is reciprocated by a drive means (not shown). The die plate 2 has a fixed side main mold 6.
and the fixed insert 7 is fixed. 8 is a taper ring, 9 is a spring push, 10 is a guide pin, and 11, 11, . . . are cooling water flow paths. A mold mounting plate 12 is fixedly attached to the die plate 3, and a movable main mold 13 is mounted at a distance from the mold mounting plate 12.
is provided. 14, 14 is the movable side main mold 1
The fixed part 3 is called a spacer block. A movable insert 15 is fixed to the movable main mold 13. 16, 16, . . . indicate cooling water flow paths. A gap 50 between the facing surfaces of the movable insert 15 and the fixed insert 7 is the product part of the injection molded product. Movable main mold 1
3 and the mold mounting plate 12, there is provided an extrusion plate 17, which is made up of two overlapping plates, and is movable reciprocally by means of ejector plate guide pins 18, 18. A plurality of extrusion pins 19, 19, . . . are provided protruding from the extrusion plate 17. The extrusion pins 19, 19, . . . are for peeling off the injection molded product 50 from the movable insert 15, and pass through the movable main mold 13 and the movable insert 15. A coil spring 20 is compressed between the extrusion plate 17 and the movable main die 13. 21 and 22 indicate recesses that hold the coil spring 20 in its position.

Reference numeral 23 denotes an extrusion rod, which functions to move the extrusion plate 17, passes through the die plate 3 and the mold mounting plate 12, and its tip is formed so that it can freely approach and separate from the extrusion plate 17. has been done. The proximal end of the extrusion rod 23 is
It is fixedly attached to the extrusion rod drive section 24. The extrusion rod drive section 24 includes an extrusion plunger 25;
A movable plate 2 fixed at the tip of the piston rod 26
It consists of 7. The extrusion rod 23 is screwed and fixed to the movable plate 27. 28 indicates a nut. Further, 29 and 30 are the movable plates 27
Shows a guide rod to guide you.

To explain the operation of this conventional example, an injection molded product 50 is molded with the movable insert 15 in the position shown in FIG. Next, the die plate 3 is moved in a direction away from the other die plate 2 by a driving means (not shown). This causes the movable insert 15 to separate from the fixed insert 7. At this time, the injection molded product is separated from the fixed insert 7 together with the movable insert 15 while being attached to the movable insert 15. Further, the extrusion plate 17, the extrusion rod 23, and the extrusion rod drive unit also move integrally with the die plate 3.

Next, the movement of the die plate 3 is stopped, and the extrusion rod drive section 24 is activated to extrude the extrusion rod 23 toward the fixed insert 7. As a result, the tip of the extrusion rod 23 pushes the extrusion plate 17, and the extrusion plate 17 moves and the extrusion pin 19,
19, ... peel off the injection molded product attached to the movable insert 15. Thereafter, the extrusion rod 23 is pulled back by the extrusion rod driving section 24, and the extrusion plate 17 is also pushed back by the repulsive force of the contracted coil spring 20. Then, the die plate 3 moves toward the other die plate 2 and enters the initial state.

FIG. 8 is an exploded perspective view of main parts showing another conventional example. A removable slide plate 31 is configured to be inserted into an insertion hole 32 provided in the extrusion plate 17. A circular hole 33 and a long hole 34 are bored in the slide plate 31 so as to communicate with each other. An insertion hole 37 is provided in the extrusion plate 17 at a position facing the circular hole 33 and on the surface on the extrusion rod 23 side. In addition, the extrusion rod 23
A constricted portion 35 is formed at the tip of the head, and the tip is formed as a retaining head 36. The other configurations are the same as those of the conventional example.

To explain the operation of this conventional example, the slide plate 31 is inserted into the insertion hole 32 of the push-out plate 17, and first, the hole centers of the circular hole 33 and the insertion hole 37 are aligned. In this state, the tip of the extrusion rod 23 is inserted into the insertion hole 37. Next, slide plate 3
1 so that the insertion hole 37 and the elongated hole 24 face each other. As a result, the retaining head 36 cannot be pulled out onto the slide plate 31 via the constricted portion 35. In this state, the reciprocating motion of the extrusion rod is transmitted to the reciprocating motion of the extrusion plate 17.
Therefore, in this conventional example, there is no need to compress the coil spring 20.

[Problem that the invention seeks to solve]

However, in the prior art shown in FIG. 7, since the extrusion rod 23 and the extrusion plate 17 are constructed as separate bodies, the coil spring 20 must be compressed in order to push back the extrusion plate 17. There was a problem that the structure of the entire mold 1 became complicated. Since the injection molding die 1 is made solidly for each injection molded product, providing the coil spring 20 and the recesses 21 and 22 for holding the coil spring 20 in each injection molding die 1 means that the injection molding die 1 is There was a problem in that the manufacturing process for the mold increased and the cost increased. Furthermore, there was a problem in that the reliability of operation was poor with only spring force, and sometimes the push-out pins 19, 19, . . . did not return.

Further, in the conventional technique shown in FIG. 8, since the slide plate 31, the insertion hole 32, etc. must be provided for each injection mold, the structure becomes complicated and the cost increases. Furthermore, there was a problem in that the setup process when attaching the mold to the injection molding machine was complicated.

[Means and actions for solving problems]

In the present invention, an elongated hole is simply formed in the extrusion plate of the injection mold, and a retaining head that can be inserted into the elongated hole through a constriction is provided at the tip of the extrusion rod. By attaching the proximal end to the extrusion rod drive unit so as to be rotatable around the axis, and by providing a rotation means for rotating the extrusion rod at this base end, the tip of the extrusion rod is first inserted into the elongated hole of the extrusion plate. After that, the extrusion rod is rotated by the rotating means, whereby the extrusion rod and the extrusion plate are integrated by the retaining head.

[Embodiments of the invention]

FIG. 1 is a sectional view of an injection molding apparatus according to the present invention;
Figure 2 is a side view of the extrusion rod, Figure 3 is a side view showing a part of the extrusion rod in cross section, Figure 4 is a front view seen from the direction of Figure 3, and Figure 5 is the extrusion rod. A front view showing the rotating means, and FIG. 6 shows a front view of the extrusion plate. As shown in FIG. 6, elongated holes 38, 38, . Note that the push-out pins 19, 19, . . . are omitted in this figure.

A retaining head 40 is provided at the tip of the extrusion rod 23 and can be inserted into the elongated hole 38 through a constricted portion 39. The retaining head 40 is formed into an oval shape that is approximately the same as the elongated hole 38, and when the longitudinal directions of both 38 and 40 match, the retaining head 40 can be inserted into the elongated hole 38, and when the longitudinal directions intersect ( 6th
(dotted line position in the figure), the extrusion rod 23 and the extrusion plate 17 are configured to be integrated. The thickness of the extrusion plate 17 is made slightly larger than the length of the constricted portion 39,
It is desirable to have a shape that makes it easy to bite but does not cause large rattling.

The proximal end of the extrusion rod 23 is attached to a movable plate 27, which constitutes an extrusion rod drive section 24, so as to be rotatable around an axis. Reference numerals 41 and 42 indicate retaining flanges, and 43 indicates a bearing. Note that the die plate 3 is also provided with a bearing 44, and the extrusion rod 23 is configured to rotate smoothly by both bearings 43 and 44.

Furthermore, a rotating means 45 for rotating the extrusion rod 23 is provided at the base end of the extrusion rod 23. The rotating means 45 is composed of a sprocket 46 provided on the extrusion rod 23 and a driving chain 47 provided on the movable plate 27 (FIG. 5). Both ends of the chain 47 are connected to a hydraulic plunger 48 which serves as a driving source. The hydraulic plunger 48 is configured to rotate the extrusion rod 23 approximately 90 degrees. Reference numeral 49 indicates a tensioner that prevents the chain 47 from becoming slack. The rest of the structure is the same as that of the conventional example, so the same parts are given the same reference numerals and the explanation will be omitted.

Next, the operation of this embodiment will be explained. First, the injection mold 1 is installed between the die plates 2 and 3. The retaining head 40 of the extrusion rod 23 is assembled in advance in such a direction that it can be inserted into the elongated hole 38 of the extrusion plate 17. Next, the extrusion rod 23 is moved toward the extrusion plate 17, and the retaining head 40 at the tip is inserted into the elongated hole 38. After that, when the hydraulic plunger 48 is operated and the chain 47 is driven, power is transmitted through the sprocket 46, and the extrusion rod 23 rotates around its axis, thereby causing the extrusion plate 17 to be moved by the retaining head. and extrusion rod 23 are integrated. To separate them, the chain 47 is driven in the opposite direction by the hydraulic plunger 48, the retaining head 40 and the elongated hole 38 are aligned in the same direction, and the extrusion rod 23 is pulled out.

〔Effect of the invention〕

According to the present invention, since long holes are simply formed in the injection mold, even if the long holes are formed in each injection mold, the structure does not become complicated. In addition, the manufacturing process can be simplified and costs can be reduced.

Forming a retaining head on the extrusion rod and providing a rotation means can be said to make the structure of the extrusion rod a little more complicated than before, but by forming one extrusion rod, all injection molding molds can be Because it can be used for molds, coil springs 20 and slide plates 31 are individually attached to each injection mold.
The manufacturing process for the entire injection molding device can be simplified compared to forming the injection molding device. Furthermore, compared to the conventional embodiment shown in FIG. 8, the time required for attaching and removing the mold can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an injection molding apparatus according to the present invention;
Fig. 2 is a perspective view of the extrusion rod, Fig. 3 is a side view showing a part of the extrusion rod in cross section, and Fig. 4 is a perspective view of the extrusion rod.
FIG. 5 is a front view showing the rotating means of the extrusion rod, FIG. 6 is a front view of the extrusion plate, FIG. 7 is a sectional view of a conventional injection molding device, and FIG. FIG. 7 is an exploded perspective view of a main part of another conventional example. DESCRIPTION OF SYMBOLS 1... Injection mold, 15... Movable insert, 17... Extrusion plate, 19... Extrusion pin, 23... Extrusion rod, 24... Extrusion rod drive part, 38... Long hole, 3
9... Narrow portion, 40... Removal prevention head, 45... Rotating means.

Claims (1)

[Claims] 1. A long hole is bored in the extrusion plate holding the extrusion pin for peeling off the injection molded product from the movable insert of the injection mold, and the elongated hole is inserted through the constriction into the tip of the extrusion rod that moves the extrusion plate. A retaining head that can be inserted into the hole is provided, the proximal end of the extrusion rod is rotatably attached to the extrusion rod drive unit around the axis, and a rotating means for rotating the extrusion rod is provided at the base end. injection molding equipment.