JPS6119439B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for manufacturing a synthetic resin nib for use in writing implements such as markers and felt-tip pens, in which the shaping openings of the nib are segmented or continuous in a mutually communicating manner. The melt shaping passage is divided into blocks, and a required number of melt speed adjusting passages having a smaller diameter than the melt shaping passage and adjusting the melt passage speed of the shaping passage almost the same are provided between the shaping opening of the block and the die body. The present invention is characterized in that a tapered guide passage is provided between each melt speed adjustment passage and the melt shaping passage, which is inclined from the front end of the melt speed adjustment passage to the rear end of the melt shaping passage and communicates with the melt shaping passage without any difference in level.

And, the present invention has a tapered guiding passage.
A stagnation phenomenon occurs at the rear end of the melt shaping passage when the melt moves from the small-diameter melt speed adjustment passage to the large-diameter melt shaping passage, and the stagnant melt is dried and solidified by the heat of the heated die. This phenomenon accumulates and destabilizes the melt flow velocity in each melt shaping passage, and the ink passage cannot be formed due to the mismatch in melt flow velocity in each melt shaping passage.Therefore, the accumulated solid resin described above is removed at regular intervals. It is possible to continuously mold a pen nib having a cross-sectional shape having an ink passage having a predetermined porosity without incurring any trouble or production stoppage loss during the process.

An example of implementation of the present invention will be described in detail below based on the drawings.

The die body A has a built-in screw (not shown), and the synthetic resin in the form of powder or particles falling from the hopper (not shown) is transferred to the melt reservoir space B-1.
from there to the flow rate control section B. Therefore, during the transfer, the die body A is heated from the outside with a heater (not shown) to melt the synthetic resin while being transferred.

In addition, the die body A is provided with an air blowing pipe A-1 and an air feeding path A-2 communicating with this blowing pipe, and the air feeding path is connected to the center of the flow rate control section B and the center of the injection section D. The blowhole A-3 is opened at the injection surface. Air blowing pipe A-
1 and air supply path A-2 are filled with blowhole A-3 by blowing compressed air during the stretching process during pen nib manufacturing.
This is to prevent the synthetic resin from concentrating at the center by ejecting it from the center, thus forming a pen nib E without a core at the center.

The die body A has a shaped opening C formed in its front portion, that is, the injection surface, communicating with the ink reservoir B-1 at the rear via a flow rate control portion B and a tapered guide passage E. This shaped opening C-2 has a roughly pipe-shaped outer shaped opening C-2 that is concentric with the fumarole hole A-3, and a plurality of partition walls that extend from the inside of the opening C-2 independently from each other in the direction of the central fumarole hole A-3. These openings C-2 and C-1 are subdivided into a plurality of melt shaping passages 1 that communicate with each other and are arranged.

Roughly pipe-shaped outer shaping opening C-2 is constructed by drilling a total of 72 melt shaping passages 1, 36 for both inner and outer rings in the drawing, in a manner that communicates with each other, and 72 blocks that communicate the opening space with each other. Subdivide into.

The bulkhead shaping opening C-1 is composed of a main bulkhead shaping opening Ca that communicates with the inside of the outer contour shaping opening C-2 and extends toward the central fumarole hole A-3, a secondary bulkhead shaping opening Cb, and a secondary bulkhead shaping opening Ce. The main bulkhead shaping openings Ca extending from three sides at an angle are formed so that the four melt shaping passages 1 communicate with each other, and are subdivided into four blocks communicating with each other. A sub-diaphragm shaping opening located in the middle of each opening Ca and extending from three sides.
Cb is formed by drilling three melt shaping passages 1 in communication with each other and subdividing into three blocks communicating with each other.

The secondary bulkhead shaping passage Cc, located between the main and auxiliary openings Ca and Cb and extending from six directions, is formed by making the two melt shaping passages 1 communicate with each other and subdivided into two blocks communicating with each other. to form.

In addition, the diameters of the main bulkhead shaping opening Ca, the secondary wall shaping opening Cb, and the secondary bulkhead shaping opening Cc are such that when the melt passes through these openings and is extruded, the pen tip E is equal to the ink passage width due to capillary action. Design in advance so that

Therefore, in principle, the melt shaping passage 1 has a diameter that gradually decreases from the outside toward the center of the contour shaping opening C-2. However, the present invention is not limited to this, and a large diameter passage may be provided in the middle of the partition wall shaping opening C-1.

The flow rate control section B is a melt speed adjustment passage that is interposed between a part or all of the melt shaping passages 1 and the melt reservoir B-1 as shown in the drawings, communicates them, and controls melt distribution. This melt speed adjustment passage is shown as melt speed adjustment passage B-3 for the melt shaping passage 1 in the outer shaping opening C-2, and as B-2 for the melt shaping passage 1 in the partition shaping opening C-1. However, in relation to the cross-sectional diameters of all of these melt shaping passages 1, the melt speed adjustment passages are assumed to have small diameters. Also, each melt speed adjustment passage B-
3. The cross-sectional diameter ratio relationship between the row B-2 and the melt shaping passage 1 is such that the melt passes through all 105 blocks of the melt shaping passage 1 in the outline shaping opening C-2 and the partition shaping opening C-1 on the drawing. Since the speed is the same, the diameters of the holes are different, and the same number of holes as the melt shaping passages 1 are opened.

Note that although the number of melt speed adjustment passages is set at a ratio of 1 to the plurality of melt shaping passages 1, this does not change the gist of the present invention.

The tapered guide passage E is interposed between the front end of each melt speed adjustment passage B-2, B-3 and the rear end of the melt shaping passage 1, and communicates between the two. Aisle B-
2, B-3 From the front end to the melt shaping passage 1...the passageway is uniformly inclined, that is, the cross-sectional area of the passage is gradually increased and connected without any step.

Further, it is desirable that the cone angle of the tapered guide passage E be acute.

Therefore, all of the melt shaping passages 1 are opened in a shape that resembles a series of hyotan, but this opening was achieved by dividing the shaping opening C of the pen tip E into smaller sections. , to make the mass of each part of the cross section uniform by making the melt specific gravity of the outer contour shaping opening C-2 and the partition shaping opening C-1, and the melt specific gravity within each opening C-2 and C-1 appropriate,
In addition, the cross-sectional shape of the partition wall F-1 is determined to be faithful to the shape of the partition wall shaping opening C-1 to keep the ink passage F-2 constant within the limit where capillarity is likely to occur. Each tapered guide passage E transfers the melt whose flow rate is controlled by each melt speed adjustment passage B-2 and B-3 to the partition wall shaping opening C-1 and the outer contour shaping opening C-2, while maintaining appropriate specific gravity. It exists by inducing it to flow.

That is, melt speed adjustment passages B-2, B-3
The melt extruded from the melt shaping passage 1 is guided by the tapered guide passage E, flows smoothly into the melt shaping passage 1, expands within the melt shaping passage 1, and integrates with the melt in the adjacent passage, forming the outer contour shaping opening C. ―
2 and the partition wall shaping opening C-1, and then extruded from the shaping opening C to form a pen nib F having a predetermined porosity.

Moreover, in the above embodiment, the outer contour shaping opening C-2
The projection C-3 forms an ink passage F-4 within the outer wall F-3 of the nib E.

The pen nib E manufactured by the above-mentioned apparatus has a frontal shape as shown in FIG. 3 and a cross-sectional shape as shown in FIG. Distant intermediate partition walls and short partition walls further away from the center are arranged radially and alternately as appropriate.

Therefore, the ink passages F-2 are also formed radially and joined at the center, and pass in the axial direction together with the partition walls F-1.

The outer wall F-3 is formed in a plurality of concentric rows so as to surround the partition wall F-1..., is formed integrally with the partition wall, and is provided with an ink passage F-4 passing in the axial direction. . Therefore, a large number of parallel ink passages F-5... and F-6... passing in the axial direction are provided on both sides of the partition wall F-1... and the outer wall F-3, and these are all connected to the central ink passage F-7. communicate with each other.

Therefore, it is possible to obtain a pen nib E that has no core at all in the center and has a large number of ink passages, and the partition wall gradually becomes smaller in diameter toward the center, which is rich in elasticity or flexibility, and allows ink to flow smoothly. The destination will be E.

As described above, the present invention divides the shaping opening of the pen tip into sections that communicate with each other, that is, into continuous blocks, and forms melt shaping between the shaping opening in the block and the die body. A required number of melt speed adjustment passages are provided that have a smaller diameter than the passages and adjust the melt passing speeds of the shaping passages to be almost the same, and between each melt speed adjustment passage and the melt shaping passage, melt shaping is performed from the front end of the melt speed adjustment passage. A tapered guide passage is provided that slopes toward the rear end of the passage and communicates without any steps, and this guide passage guides the melt whose flow rate has been controlled in the melt speed adjustment passage to the melt shaping passage without stagnation, resulting in the following features: be.

There is no stagnation at the rear end of the melt shaping passage when the melt moves from the small diameter melt speed adjusting passage to the large diameter melt shaping passage.

Since the melt pool was not generated, solid resin that dried and solidified and accumulated under the heat of the heated die was not generated, and the melt flow rate in each melt shaping passage was always stabilized.

The melt flow velocity in each melt shaping passage is the same, so that there is no possibility that the ink passage cannot be formed.

There is no need to remove the solid resin that has dried and accumulated at regular intervals, and there is no production stoppage loss during that time.

A cross-sectional pen nib having an ink passage with a predetermined porosity can be continuously molded.

In addition, while shaping and molding the pen tip into a predetermined shape and extruding it without letting it come in contact with the outside air inside the shaping opening, the space between each partition wall is maintained with air from the blowhole.
It is possible to reliably mass-produce synthetic resin pen nibs with ink passages that match the porosity set by the shaped opening.

Thus, the intended purpose can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a front view of the main parts of the device of the present invention, FIG. 2 is a longitudinal sectional side view taken along the - line, FIG. 3 is a front view of the pen tip, and FIG. 4 is an enlarged cross-sectional view thereof. In the figure, A is the die body, A-3 is the blowhole, and B-
2, B-3 are melt speed adjustment passages, C is a shaping opening, C-1 is a partition shaping opening, C-2 is an outer shaping opening, E is a tapered guide passage, and 1 is a melt shaping passage.

Claims (1)

[Claims] 1 At the front part of the die body, a large number of shaped openings are connected to each other and are formed of a roughly pipe-shaped outer shaped opening and a plurality of partition shaped openings that extend from the inside of the opening independently toward the central blowhole. A required number of melt speed adjustments are made by drilling and forming a melt shaping passageway between the forming opening and the inside of the die main body, the diameter of which is smaller than that of the melt shaping passageway, and the melt passage speed of the melt shaping passageway is made almost the same. A synthetic resin pen nib comprising a passage, and a tapered guide passage that slopes from the front end of the melt speed adjustment passage to the rear end of the melt shaping passage and communicates without a step between each melt speed adjustment passage and the melt shaping passage. manufacturing equipment.