JP3687709B2 - Mold device for injection molding of ink storage member having many parallel blades - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mold apparatus for injection molding of a resin molded product having a large number of parallel blades. Here, as an example of a resin molded product having a large number of parallel blades, a temporary ink storage member used for a fountain pen or a direct liquid writing instrument, or an ink jet printer which has been attracting attention in recent years. There is a temporary ink storage member used or an ink storage member for allowing ink to permeate a pad such as a stamp.
[0002]
[Prior art]
Conventionally, a mold apparatus as shown in FIGS. 8 to 11 is known as a mold apparatus for injection molding of a resin molded product having a large number of parallel blades. Inside the cavity 10, a core 11 made up of a number of parallel plates 11a is disposed. The thickness of the parallel blades of the molded product is determined by the length of the interval between the parallel plates, and the interval of the parallel blades is determined by the thickness of the parallel plate.
Next, the molding method will be described.
From the state of FIG. 8, the resin is poured into the cavity 10 from the gate 13 of the runner 12. When the resin flows into the cavity 10, the resin flows into the gaps 11b formed by a large number of parallel plates 11a. Thus, a molded product (ink storage member) is formed.
[0003]
[Problems to be solved by the invention]
The resin flowing from the gate 13 first flows into the gap 11b of the parallel plate 11a immediately below the gate 13 (see FIG. 9). Then, due to the resin flowing into only one place (gap 11b), an excessive resin inflow pressure acts on the parallel plates 11a located on both sides of the gap 11b. Due to the inflow pressure of the resin, the parallel plates 11a located on both sides of the gap 11b are tilted left and right and deformed. Then, the next gap between the collapsed parallel plates is narrowed, and the resin does not flow into the gap between the narrowed parallel plates, and further flows into the gap between the next parallel plates (see FIG. 10). .
[0004]
Thus, the parallel plate that is tilted to the left and right acts in the direction to be further tilted, and the blades are not partially molded, or conversely, the blades that are wedged due to excessive resin flow are mold release. At that time, the plate was sandwiched between the parallel plates, and the bite was broken, and when the parallel plate was greatly tilted, the parallel plate was broken and the mold was sometimes damaged.
[0005]
[Means for Solving the Problems]
The present invention includes a plurality of parallel blades in which a core having a large number of parallel plates is disposed in a cavity, and columns are provided between the parallel plates at positions parallel to the parallel plates to prevent the inclination of the parallel plates. The gist of the present invention is an injection molding die device for an ink storage member.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described in detail based on the examples shown in FIGS.
1 to 5 show a first embodiment of the present invention. Inside the cavity A of an injection mold (not shown), a core 1 made up of a number of parallel plates 1a is disposed. Further, a pillar 4 for preventing the parallel plate from falling is provided in the gap 1b formed by the multiple parallel plates 1a. The pillar 4 may be formed of a member different from the parallel plate 1a and may be disposed and fixed in each gap 1b, but may be directly formed integrally with the parallel plate 1a. The processing is somewhat troublesome, but by forming the parallel plate and the column integrally, it is possible to prevent the column itself from falling.
Reference numeral 3 located in the upper central portion of the cavity A is a gate for pouring resin into the cavity A, and a runner 2 is also continuously formed on the gate 3.
[0007]
In the above example, the column 4 is provided at the central portion of the parallel plate 1a and at a position directly below the gate 3. However, the column 4 is provided at two positions about 1/3 from both ends of the parallel plate 1a. Further, it may be provided at three locations, that is, a central portion of the parallel plate 1a and a position of about 1/3 from both ends. When the inflow pressure of the resin is large or the viscosity of the inflowing resin is high, the parallel plate is more difficult to fall down, which is a particularly effective means.
[0008]
Next, the molding method and operation will be described.
The resin flows into the cavity A from the gate 3 through the runner 2. The resin that has flowed into the cavity A flows into the gap 1b formed by each parallel plate 1a. At this time, as in the prior art, the resin first flows into the gap 1b of the parallel plate 1a immediately below the gate 3, and an excessive inflow pressure of the resin acts on the parallel plates 1a located on both sides of the gap 1b. Since each pillar 1 is provided in each gap 1b, the parallel plate 1a does not fall down (see FIG. 3), and the resin flows smoothly. Then, the resin flows evenly into the next gap 1b in the horizontal direction one after another (see FIG. 4).
Thus, an ink storage member 5 having a large number of parallel blades 5a and grooves 5b as shown in FIG. 5 is obtained.
[0009]
FIG. 6 shows a second embodiment of the present invention.
In this example, an inclined surface is formed above the pillar 6 (corresponding to the pillar 4 in the previous example), and a draft 6a is provided. The mold releasability from the cavity A of the molded product when the mold is expanded is improved. This is because the blade 5a is thin because the molded product is small, and the thin blade is not broken (not torn).
[0010]
FIG. 7 shows a third embodiment of the present invention.
An inclined surface is formed above the parallel plate 7 to provide a draft angle 7a. Of course, a draft angle may be provided for both members of the column 6 and the parallel plate 7.
[0011]
【The invention's effect】
The present invention includes a plurality of parallel blades in which a core having a large number of parallel plates is disposed in a cavity, and columns are provided between the parallel plates at positions parallel to the parallel plates to prevent the inclination of the parallel plates. Since the mold device for injection molding of the ink storage member is used, the ink storage member having parallel blades can be molded and the mold is not damaged.
[Brief description of the drawings]
FIG. 1 is an enlarged partial perspective view of a core according to a first embodiment of the present invention.
FIG. 2 is a perspective view of the outer appearance of a core in FIG.
FIG. 3 is a front sectional view of a resin filling process into the core of FIG. 2;
4 is a front sectional view at the end of resin filling in FIG. 3;
5 is an external perspective view of the molded product of FIG. 4. FIG.
FIG. 6 is an external perspective view of a pillar portion of a second embodiment of the present invention.
FIG. 7 is an external perspective view of a pillar portion of a third embodiment of the present invention.
FIG. 8 is an enlarged partial perspective view of a core of a conventional mold.
FIG. 9 is a front sectional view of the mold of FIG. 8 at the start of injection.
FIG. 10 is a front sectional view of the filling process of FIG. 9;
FIG. 11 is a front sectional view at the end of filling in FIG. 10;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Core 1a Parallel plate 2 Resin runner 3 Gate 4 Column 5 Ink storage member 5a Parallel blade 6 Column 6a Draft gradient 7 Parallel plate 7a Draft gradient 8 Column

Claims (1)

An ink storage member having a plurality of parallel blades in which a core having a large number of parallel plates is disposed in a cavity, and columns are provided in parallel with the parallel plates to prevent the inclination of the parallel plates between the parallel plates. Molding equipment for injection molding.

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