JPH09234986A - Manufacture of ball-point pen point set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the possibilities that a ball is dislocated out of place and obtain a deposited product of uniform and stable strength by bringing a ball pen tip into contact with an elastic member at the time of ultrasonic deposition, in a ball-point pen point set consisting of a tip holder and an ink guide core of a fiber bundle firmly welded by ultrasonic deposition. SOLUTION: When manufacturing a ball-point pen point set, first a stainless steel ball-point pen tip 1 is pressed into the center hole 2a of a tip holder 2, then is fixed in such a state that the tip is protruded, and an ink guide core 3 is inserted from the center hole 2a to temporarily set the ball-point pen point set. Next, a fixture 4 is installed for positioning and the rear part of the ink guide core 3 is pressed by a spring. After that, the tip holder 2 is fixed into a fixture 6 for immobilization from the periphery using the fixture in such a way that the holder 2 does not rock. In addition, the point of the tip 1 is brought into contact with a fixture 7. Finally, a horn 8 connected to an ultrasonic welder, and both 2, 3 are welded under the effect of an ultrasonic vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tip holder in which a ball-point pen tip, which holds a ball as a writing member at its tip, is fixed to the front part of a bore, and a fiber bundle body for guiding ink into the ball-point tip. And a method of manufacturing a ball-point pen tip set including a ball-point pen tip, a chip holder, and an ink-guide core by fixing the ink-guide core and the ink-guide core by ultrasonic welding.

[0002]

2. Description of the Related Art Conventionally, as a member for guiding ink contained in an ink tank into a ball-point pen tip, a member using a fiber bundle such as acrylic fiber or polyester fiber as an ink guiding core is known. Here, the ink guide core is such that the positional relationship between the ink guide core and the ball-point pen tip should be strictly controlled, and if there is a space between the ink guide core and the ball-point pen tip,
If the ink guide core is too strongly pressed against the ballpoint pen tip, the space inside the fiber will be lost. The rate was locally reduced, making it difficult for ink to pass through, and in the end, poor handwriting of ink to the pen tip resulted in blurring of handwriting. From the above, the ink guide core and the chip holder are welded and positioned and fixed,
Attempts have been made to make the positional relationship between the ball-point pen tip and the ink guide core good and to prevent the good positional relationship from being impaired by vibration, impact or the like.

As a welding method, a thermal trowel with a thin tip is used, and the trowel is inserted between the rear part of the chip holder and the ink guide core inserted in the inner hole of the chip holder to melt and fix both members at the same time. , The so-called heat welding method, or the tip of the ultrasonic horn is made as thin as the tip of the thermal iron,
In order not to break the subtle processing in the tip, the pen tip is made non-contact with other members, and while oscillating the ultrasonic wave, the tip holder and the ink induction core inserted in the inner hole of the tip holder and the ball-point pen tip There is known a so-called ultrasonic welding method in which an ultrasonic horn is pressed to melt and fix both members at the same time.

[0004]

In the heat welding method using a heat iron, the temperature of the heat iron is easily affected by changes in the environment of the outside air, and it is extremely difficult to always keep the temperature constant.
Therefore, there is a problem that it is difficult to perform processing with uniform welding strength, and the welding strength tends to be insufficient. If the temperature of the heat iron is increased or the welding time is lengthened so that the welding strength does not become insufficient, the amount of resin or the like melted out increases, which may adversely affect the connection relationship with other members such as the barrel. There is a risk of adversely affecting the ink passages such as the ink guide core and the hole of the ballpoint pen tip, and there is also a problem that the appearance becomes messy.

Further, when the ultrasonic welding method is adopted, the ultrasonic vibration cannot be applied only to the portion to be welded. That is, the ultrasonic vibration is also transmitted to the ball-point pen tip connected to the tip holder, and sometimes the delicate shape in the ball chamber holding the ball as the writing member is destroyed. By making the tip of the ball-point pen tip out of contact with other members, it is possible to suppress the effect of ultrasonic vibration transmission to some extent, but when ultrasonic vibration is transmitted to the tip edge part that prevents the ball from falling off, There has been a problem that the fore edge part spreads out, or an outward force is applied to the ball itself, which easily causes a ball detachment phenomenon. If the ultrasonic vibration is adjusted to such an extent that the ball detachment phenomenon does not occur, and the welding is performed by shortening the ultrasonic vibration application time, for example, the desired welding strength cannot be obtained, and the product drops when it is made into a product. There is a problem in that the positional relationship between the ink guide core and the ball-point pen tip changes due to the impact caused by vibration, vibration during transportation, etc., and defects such as handwriting scratches occur.

[0006]

That is, according to the present invention, ink is guided into a tip holder in which a ballpoint pen tip having a ball as a writing member held at its tip is fixedly projectingly fixed to the front part of a central hole and a ballpoint pen tip. In a method of manufacturing a ball-point pen tip set in which an ink guide core made of a fiber bundle is fixed by ultrasonic welding, when applying ultrasonic waves to the tip holder and the ink guide core, the tip of the ball-point pen tip touches an elastic member. The gist is a method of manufacturing a ballpoint pen tip set, which is characterized by contacting with each other.

[0007]

An embodiment will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing a process of applying ultrasonic waves to a ballpoint pen tip set including a ballpoint pen tip 1, a tip holder 2, and an ink guide core 3. The ball-point pen tip 1 made of stainless steel is press-fitted into the inner hole 2a of the tip holder 2 made of polyacetal resin and fixed with the tip protruding, and then the inner hole of the tip holder 2 so as to reach the inside of the ball-point pen tip 1. An ink induction core 3 which is a bundle of polyester fibers is inserted from 2a, and a ballpoint pen tip set including a ballpoint pen tip 1, a chip holder 2 and an ink induction core 3 is temporarily attached.

A chip holder receiving jig 4 made of stainless steel for positioning the temporarily attached ballpoint pen tip set.
In order to suppress poor contact between the ink guide core and the chip holder, the rear part of the ink guide core is pressed by the spring 5 with a force of 100 to 500 g. Next, the tip holder 2 is fixed from the surroundings by a fixing jig 6 made of stainless steel so as not to swing inside the jig, and the tip of the ballpoint pen tip 1 is made of an NBR plate ballpoint pen having a thickness of 3 mm and a hardness of 80 °. Contact the chip receiving jig 7. Finally, ultrasonic welding machine 9 (manufactured by Ultrasonic Industries Co., Ltd .: USWP-200Z2)
8S type) and a horn 8 (tip diameter; 1.2 mm) for applying ultrasonic vibration are brought into contact with the chip holder 2,
Ultrasonic vibration with an output of 200 W and a frequency of 28 KHZ is applied. The ultrasonic wave vibration causes the horn 8 to be pierced while melting the chip holder 2, and the horn 8 causes the ink guide core 3
To reach the end of welding.

For comparison, a test was conducted by changing the time for applying ultrasonic vibration. Further, a test was carried out when the materials of the chip holder receiving jig 4 and the fixing jig 6 were changed.

Further, as comparative examples, a test in which the fixing jig 6 was not used and a case where the ball-point pen tip receiving jig 7 was not brought into contact with the tip of the ball-point pen tip and a test by a heat welding method were also conducted. The samples used for each test are shown in (Table 1).

[0011]

[Table 1]

Test 1 The presence or absence of balls was visually inspected for 100 samples of each of the above-mentioned Examples and Comparative Examples.

Test 2 For the welding strength, the pull-out strength of the ink induction core was measured with a push-pull gauge (made by Imada Co., 0-5 kgf measurement), and the stability of the welding strength was compared (maximum value and minimum value).

Test 3 100 samples of each Example and Comparative Example were assembled in a writing instrument and written by a writing tester, and the number of scratches of handwriting was counted.

Test 4 The contact state between the ink guide core and the chip holder after dropping 100 m from each of the above-mentioned Examples and Comparative Examples from the height of 1 m of the concrete floor was examined. The results of Test 1 to Test 4 are shown in (Table 2) and (Table 3).

[0016]

[Table 2]

[0017]

[Table 3]

[0018]

As described above, according to the method of manufacturing a ballpoint nib set of the present invention, the ball does not come off during ultrasonic welding, and a uniform and stable welded material having high strength can be obtained. .

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a step of applying ultrasonic waves.

[Explanation of symbols]

 1 Ballpoint Pen Tip 2 Tip Holder 2a Medium Hole 3 Ink Induction Core 4 Tip Holder Receiving Jig 5 Spring 6 Fixing Jig 7 Ballpoint Pen Tip Receiving Jig 8 Horn

Claims (1)

[Claims] 1. A tip holder having a ball-point pen tip, which holds a ball as a writing member at its tip, projectingly fixed to the front part of the inner hole, and an ink guide core made of a fiber bundle for guiding ink into the ball-point pen tip. In a method of manufacturing a ballpoint pen tip set that is fixed by ultrasonic welding, when applying ultrasonic waves to the tip holder and the ink induction core,
A method of manufacturing a ball-point pen tip set, wherein the tip of the ball-point pen tip is brought into contact with an elastic member.