JP2002011765A - Injection mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection mold suitable for manufacturing plural kinds of molded articles low in amount of production. SOLUTION: A plurality of unit molds 14A-14D obtaining single-cavity molded articles are attached to a common mold base 12 in a freely detachable manner through block type lock mechanisms 16 and slide type lock mechanisms 18 and mounted on the common mold base in a freely detachable manner from the parting line surface side of a fixed mold 62 and a movable mold 64. Resin flow rate adjusting mechanisms 44R, 44L, 46a-46d are respectively provided to the main runners 38R, 38L and branch runners 40a-40d formed to the common mold base 12 and the unit molds 14A-14D in a branched state in order to fill the cavities 36a-36d formed to the unit molds 14A-14D with an injected molten resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for injection molding, and more particularly, to a small quantity product (a molded product with a small production amount).
The present invention relates to an injection mold suitable for simultaneously producing a plurality of types.

[0002]

2. Description of the Related Art Some injection-molded articles made of synthetic resin have a small production amount. When such a small quantity is produced by injection molding of a synthetic resin, a single unit mold having only one cavity for the injection molding is set in the injection molding machine, and shots are repeated for the number of productions.
A so-called single-piece production system for producing a predetermined number of molded products has been generally used. Such one
According to the individual production system, an injection-molded product can be obtained even with a small quantity, which is certainly suitable for the production of a small quantity.

[0003]

However, according to such a conventional single-unit production system using a single unit mold, only one molded product can be obtained in one shot even if the production number is small. Therefore, the occupation time for one injection molding machine is long, and the production unit price per product (molded product) is high.

[0004] Further, when trying to produce a plurality of types of molded products with this injection molding machine, the production of the next molded product cannot be started until the production of the previous molded product is completed. Production delays were delayed, and production efficiency was poor.

[0005] If a plurality of injection molding machines are provided to avoid this, problems such as an increase in equipment costs and a need to secure an installation space also arise.

[0006] Under such circumstances, some of the small items,
There are many specifications having the same resin material and the same coloring pigment (that is, the same hue of the molded product). In such a case, if these can be produced simultaneously, the production time can be reduced and the production cost can be reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide an injection mold capable of simultaneously producing a plurality of small-quantity products. It is in. This aims to improve the production efficiency of small-volume products and reduce production costs.

[0008]

According to a first aspect of the present invention, there is provided an injection molding die having a plurality of unit molds for obtaining a single-piece molded product. The gist is that it is detachably attached to the mold base via a lock mechanism.

According to the injection molding die having the above-mentioned structure, a plurality of small-quantity products can be produced at the same time, so that the production waiting state is avoided, and the production delivery date is set earlier and earlier. It will also be.

In this case, each unit mold is detachably attached to the common mold base from a parting line (PL) surface where the fixed mold and the movable mold are separated from each other and approached. If you attach it,
The mold replacement operation is performed easily and smoothly.

Further, in order to fill the cavity formed in each of the unit molds with the molten resin to be injected, a runner formed in a branch shape in the common mold base and each unit mold. If each runner) is provided with a molten resin flow rate adjustment mechanism,
Even if there is a difference in shape, weight, etc. between molded products produced in each unit mold, the molten resin is filled into the cavity of each unit mold in a well-balanced manner.

Further, the injection mold of the present invention is provided in claim 4.
As described in the above, a fixed mold and a movable mold that can be separated from and approached to the fixed mold surface, and a plurality of unit molds for obtaining a single molded product can be mounted on these molds. A mold base is attached, and each of the unit molds is removably mounted on the common mold base.
The gist is that a runner for filling a molten resin into a cavity for an individual molded product is formed in a branch shape in the common mold base.

In this case, if each unit mold is mounted on the common mold base from the parting line (PL) side of the fixed mold and the movable mold, the mold changing operation is easy. Also, if a flow rate adjusting mechanism of the molten resin is provided in a runner formed in a branch shape across the common mold base and each unit mold,
Molded products with different shapes can be produced with good filling balance.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a schematic configuration of an injection mold according to an embodiment of the present invention. The illustrated injection molding die 10 has four mold mounting holes H1 to H4 on a common mold base 12 surface.
H4 is provided, and unit molds 14A to 14D are detachably mounted in the respective mold mounting holes H1 to H4.

That is, the unit mold 1 is inserted into each of the mold mounting holes H1 to H4 of the common mold base 12.
4A to 14D are mounted so as to be flush with each other, and a corner of each unit mold 14A to 14D is fixed by a block-type lock mechanism 16, and each unit mold 14A is fixed.
The edge near the corner on the opposite side of to 14D is fixed by a slide lock mechanism 18.

FIG. 2 shows a detailed structure of the block-type lock mechanism 16. As shown in FIG. Each unit mold 1
One corner wall of each of 4A to 14D has a divergent tapered surface, and a wedge-shaped fixing block 22 is provided in a gap hole 20 provided between the common mold base 12 and the corner wall of each unit mold 14A to 14D. Are fixed, and fixing bolts 24 are attached to the fixing block 22 and fastened to the mounting plate 26, whereby each of the unit molds 14A to 14
D is fixedly fastened to the mounting plate 26.

As shown in FIGS. 3 and 4, a slide groove 28 is provided in the common mold base 12, and each of the sliders 30 mounted in the slide groove 28 is provided with a slider 30, as shown in FIGS. Unit mold 1
Each of the unit molds 14A to 14D is slid and attached to the notch step 31 on the other side edge side of the unit molds 14A to 14D.
A to 14D are common mold base 1 so that they cannot be removed.
It is fixed to 2.

On the front surface of the common mold base 12, the unit molds 14A to 14A which are arranged vertically and horizontally are arranged.
Hot water for filling the cavity 36a to 36d for a single-piece molded product formed in each of the unit molds 14A to 14D with molten resin injected from the injection nozzle, which will be described in detail later, through a sprue at the center position of the 4D. Roads (main runners) 38R and 38L are the upper two unit molds 1
4A, 14B and two lower unit molds 14C,
14D and are formed in horizontal directions opposite to each other (a direction of 180 degrees).

Further, the main runners 38R, 38L are also branched in the vertical direction opposite to each other from the front end portions thereof, and the upper and lower unit molds 14A, 14C and 14
Branch runners 40a, 40c and 4 for filling the respective cavities 36a to 36d of B, 14D with the molten resin.
0b and 40d are formed. The respective branch runners 4
Cavities 36a to 36 for one-piece injection molded products provided at the substantially center positions of the unit molds 14A to 14D at the tips of 0a to 40d via gates 42a to 42d.
d.

Each of the main runners 38R and 38L is provided with a corresponding one of the main runners 38R as shown in FIGS.
R, 44L are provided with resin flow rate adjusting mechanisms 44R, 44L for adjusting the flow rate of the molten resin flowing through the R, 38L, and the cavities 36a-36d of the unit molds 14A-14D are similarly provided in the branch runners 40a-40d. There are provided resin flow rate adjusting mechanisms 46a to 46d for adjusting the filling amount of the molten resin to be charged into the resin.

FIG. 6 representatively shows one of these resin flow rate adjusting mechanisms provided on the main runner 38R. The resin flow rate adjusting mechanism 44R includes a main runner 38.
A flow adjusting nest 48 is provided on the side wall surface of the R, and the nest 48 advances and retreats in the sliding groove 50 toward the main runner 38R, and a bolt inserted into a long slot 51 formed in the nest 48. The flow rate of the molten resin flowing through the runner 38 </ b> R is appropriately adjusted by fastening and fixing the 52 to the common mold base 12. Each branch runner 4
0a to 40d provided with resin flow rate adjusting mechanisms 46a to 4d
6d has substantially the same configuration, and a description thereof will be omitted.

FIG. 7 shows a schematic configuration of an injection mold set as one embodiment to which the injection mold 10 is applied. As generally known, the injection mold set 60 according to this embodiment includes a fixed mold 62 and a movable mold 64, and the fixed mold 6.
2 includes an injection nozzle 66 for introducing a molten resin supplied from a molten resin supply source (not shown) and the injection nozzle 6.
The main runner 38R provided on the parting line (PL) surface of the injection molding die 10 attached to the injection molding die set 60 by using the molten resin introduced from 6;
A sprue 68 for supplying to 38L is provided.

The common mold base 12 is fixed to the mounting plate 26 provided integrally with the fixed die plate 72 by fixing bolts 70,
As described above, the unit molds 14A to 14D have parting lines (PL) on the common mold base 12.
The upper and lower unit molds 14B and 14D are undetachably attached from the surface side by the above-mentioned block-type lock mechanism 16 and slide-type lock mechanism 18 (FIG. 7 shows two unit molds 14B and 14D).

On the other hand, similarly to the fixed mold 62, the movable mold 64 has the common mold base 73 and the fixed bolt 7
4 and is fixed to a mounting plate 78 provided integrally with the movable die plate 76. Each unit mold 14A on the fixed mold 62 side is fixed to the common mold base 73.
Molds 75A to 75D corresponding to １４14D
(Only the unit molds 75B and 75C are shown in FIG. 7). The block mold lock mechanism and the slide lock mechanism are also irremovably attached from the parting line (PL) side. And the movable mold 6
4, a piston rod 80 of a cylinder device (not shown) is connected to the rear surface of the movable die plate 76, and the movable die 64 is fixed to the fixed die 62 by the forward and backward movement of the piston rod 80.
They are separated and approached toward the surface.

According to the injection-molding mold set 60 thus configured, the fixed mold 62 and the movable mold 6
When the preparation is completed in a state where the common mold bases 12 and 73 described above are attached to 4 and four unit molds 14A to 14D are mounted at predetermined positions of the common mold base 12, production is started. At this time, the movable die 64 advances toward the surface of the fixed die 62 by the extension movement of the piston rod 80 of the cylinder device (not shown), and the fixed die 6
The mold is clamped in a state where the parting line surfaces of the movable mold 64 and the movable mold 64 are overlapped, and then injection molding of the molten resin is started.

The molten resin injected into the mold from the molten resin nozzle 66 is supplied to the main runner 38 via the sprue 68.
R, 38L, and the molten resin distributed to the main runner 38R is further branched into branch runners 40b, 40d to fill the cavities 36b, 36d formed by the unit mold 14B and the unit mold 14D, respectively. The molten resin distributed to the runner 38L is branched into branch runners 40a and 40c, and similarly filled into cavities 36a and 36c formed by the unit molds 14A and 14C.

After filling, each unit mold 14A-
When the resin in the cavities 36a to 36d of the 14D is hardened, the movable mold 64 is separated from the surface of the fixed mold 62 by the contraction movement of the piston rod 80 of the cylinder device, and the mold is opened. At this time, as shown in FIG. 8 and FIG. 9, the injection by the unit molds 14A to 14D is performed below the parting line surfaces of the fixed mold 62 and the movable mold 64 of the injection mold set 60. A product separation shooter 82 for separating and recovering the molded product is installed, and the molded product by the lower unit molds 14C and 14D is separated at the gate portion and dropped and separated into two shooters of the product separation shooter 82, respectively. Upper unit mold 1
The molded products 4A and 14B are also separated by the gate portion and are gripped by the chuck member 84 and moved to positions just above two other shooters of the product separation shooter 82, and the gripping state of the chuck member 84 is released. And fall to each shooter to be separated.

When the first (first shot) injection molding is completed, the second and third shots are repeated. In this embodiment, four types of molded products are produced one by one at the same time. As a result, molded products having different shapes can be produced by one injection molding machine without waiting for time.
The time dedicated to the molding machine will be shortened accordingly. In this embodiment, since four types of molded products are produced at the same time, the time dedicated to the molding machine is reduced to almost one-fourth.

Further, according to the production system of this embodiment, since each molded product is separated from each gate portion at the stage of mold opening after injection molding, the runner portion is separated. At the stage of opening the mold after injection molding, the molded product is separated from the molded product, becomes recyclable, and is immediately recycled.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, an example in which four types of molded articles are simultaneously produced has been described.
It may be one that simultaneously produces a number of types, or five types of molded articles. Also, not all unit molds need to produce different-shaped products. For example, two of the four unit molds have the same shape and the other two have different shapes. There may be. Thereby, for example, even if the production amount of each molded article is different, it can cope with it. By the way, if 5000 units of A product and 2500 units of B product and C unit are each set, two unit molds for A product and one unit mold for B product and C product will be set at the same time. It is calculated that the production of the number is completed.

[0031]

According to the injection molding die of the present invention, since a plurality of single-piece molded products can be produced at the same time, the dedicated time of the injection molding machine can be reduced, and the production efficiency can be reduced. This is a significant improvement. Further, by adopting such a production system, it is not necessary to prepare a large number of single injection molding machines, and the equipment cost can be reduced. In addition, the benefits are extremely large, such as shorter delivery times and real-time recycling of runner materials.

[Brief description of the drawings]

FIG. 1 is a view showing a schematic configuration of an injection mold according to an embodiment of the present invention.

FIG. 2 is a detailed configuration diagram of a block-type lock mechanism 16 shown in FIG.

FIG. 3 is a detailed configuration diagram of a slide lock mechanism 18 shown in FIG.

FIG. 4 is a sectional view taken along line AA in FIG. 3;

FIG. 5 is an enlarged view of a resin flow rate adjusting mechanism provided in a main runner and a branch runner.

FIG. 6 is a detailed configuration diagram of a resin flow rate adjusting mechanism 44L shown in FIG. 5;

FIG. 7 is a schematic configuration diagram of an injection molding machine to which the injection mold is applied.

FIG. 8 is a diagram showing a schematic configuration of the injection molding machine in a mold open state.

9 is an external perspective view of the product separation shooter shown in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 Injection molding die 12 Common mold base (fixed die side) 14A to 14D Unit mold 16 Block lock mechanism 18 Slide lock mechanism 36a to 36d Cavity 38R, 38L Main runner 40a to 40d Branch runner 42a to 42d Gate 44R , 44L Main Runner Resin Flow Rate Adjusting Mechanism 46a-46d Branch Runner Resin Flow Rate Adjusting Mechanism 48 Flow Rate Adjustment Nesting 60 Injection Mold Set 62 Fixed Mold 64 Movable Mold 73 Common Mold Base (Movable Mold Side) 82 Product Separation Shooter 84 Chuck member

Claims (4)

[Claims] 1. A mold for injection molding, wherein a plurality of unit molds each for obtaining a single molded product are detachably attached to a common mold base via a lock mechanism. 2. The unit mold according to claim 1, wherein each of the unit molds is detachably attached to the common mold base from a parting line surface side where a fixed mold and a movable mold are separated and approached from each other. The mold for injection molding according to the above. 3. A runner is formed in the common mold base and each unit mold in a branch shape so as to fill a molten resin to be injected into a cavity formed in each unit mold, and each runner is individually formed in each runner. The injection mold according to claim 1 or 2, further comprising a flow rate adjusting mechanism for the molten resin. 4. A common mold base comprising a fixed mold and a movable mold which can be separated from and approached to the fixed mold surface, and on which a plurality of unit molds for obtaining a single molded product can be mounted. Are mounted, and the unit molds are detachably mounted on the common mold base surface, respectively.
A mold for injection molding, wherein a runner for filling a molten resin into a cavity for an individual molded product is formed in a branch shape on the common mold base.