JP3304906B2 - Tip of ball type liquid container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tip of a ball type liquid container using a ball such as a ballpoint pen refill as a writing medium.

[0002]

2. Description of the Related Art Most of the factors that determine the performance of a ball-type liquid container such as a ball-point pen depend on the precision of the tip. Even if a line of only 10 cm is drawn, the ball rotates as much as 44.5 times for a 0.7 mm ball, and 63.75 mm for a 0.5 mm ball.
The ball rotates seven times, and the ball rotates at a rapid speed. Therefore, it is extremely important for such a tip to prevent the abrasion due to the friction inevitably caused by the rapid rotation and the corrosion deterioration due to the static electricity similarly caused by the rapid rotation and to maintain the performance. It is a problem. If there is a problem in the structure and accuracy of the tip, there is a possibility that the ink during writing with a ball-point pen or the like often causes "crying out" or "bottoms".

Conventionally, as a tip of a ball type liquid container such as a ballpoint pen refill, there is an applicator described in Japanese Utility Model Laid-Open No. 5-76568. That is, in FIG. 7, the tip 1 holding the ball 11
2, a coating liquid tank 14 having a high flexibility is connected via a connection member 13 and a press-fitting cylinder 17. In the applicator in which the tank 14 is filled with a highly viscous film-forming coating solution, the ball 11 is rotatably held in a state where the ball 11 is exposed inside the tip of the tip 12, and the tip 12
The mover 15 having a small mass is arranged in the
The ball 11 is urged forward by the distal end surface of the movable element 15 which is repelled by the above, so as to contact the inward distal edge of the distal tip 12.

[0004]

However, in these prior arts which are used for controlling a liquid such as a gel ballpoint pen and a correction liquid, a ball pressing portion is formed by using a movable element as a resin molded product and a coil spring. It is difficult to incorporate parts because the number of parts also increases,
If the pitch of the coil spring exceeds twice the wire diameter, that is, the thickness of the spring, the springs are likely to be entangled with each other, so that it is not possible to rely on an automatic assembling machine and cannot cope with mass production.

In view of the above, the present invention has been made to solve the above-mentioned conventional drawbacks.
By making the gap between the coils constituting the spring at the free length smaller than the wire diameter of the spring, the entanglement of the springs is eliminated, and the end turn of the spring at the rear end of the spring that is swaged in the tip of the ballpoint pen is pitched. An object of the present invention is to make it possible to align springs in the direction of the neck fishing by making them larger than the outer diameter dimension of, and to enable assembly by an automatic machine.

Further, the present invention provides a low viscosity to a high viscosity (3.5 cps to 5,000 c at 20 ° C.) for writing.
In the knock-type or cap-type ball type liquid container using the ink of (ps), a spring is provided behind the ball in the tip of the ballpoint pen, and the spring is mounted by caulking the rear end of the holder. By biasing the ball forward by this spring and completely closing the tip opening, it is possible to prevent ink leakage from the tip of the ink and to prevent ink dry-up around the ball when carrying, other than when writing. Aim.

[0007]

In order to achieve the above object, a tip of a ball type liquid container according to the present invention has a tip of a ball type liquid container in which a coating ball is rotatably held at the tip of a holder. in the chip, with a built-in coil spring to flex in pen pressure in the holder, this co
The tip of the il spring is forward along the axis of the holder
The linear extension extending to the ball is pressed against the ball through the liquid guide hole in the tip of the holder, and the rear end of the holder is swaged to form a swaged portion, and the intermediate pitch forming the coil spring Caulked than the outside diameter of the part
The step portion is formed by increasing the outer diameter of the rear end winding portion of the coil spring.

[0008]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view showing a tip of a ball type liquid container of the present invention. In the figure, a tip 1 is composed of members such as a holder 2, a ball 3, and a coil spring 4.

More specifically, the holder 2 constituting the tip 1 has a pen tip 2a at the front end of a tubular body, and a step 2c is formed between the pen tip 2a and the thin part 2b at the rear. I have. Further, inside the pen tip portion 2a, a first step portion 2d, a second step portion 2e, and a third step portion 2f are provided, each having a gradually decreasing inner diameter in a forward direction.
An ink guide hole 2g is formed from the third step portion 2f toward the front end opening.

Next, FIG. 2 is an enlarged longitudinal sectional view of the tip portion of FIG. 1. As is clear from the drawing, the tip portion 1 has a tapered pen tip 2a at the tip of the holder 2.
For example, as a material composition, tungsten carbide (96
%) And cobalt (cemented carbide balls 3 consisting 4%) and is embraced by Rikai rolling can to the distal crimped portion 2i.

This point will be described in more detail with reference to FIGS. 3 and 4. The inside of the tip of the holder 2 is provided with an ink guide hole 2g.
A ball holding portion 2h is provided in the front inner peripheral portion of the ink guide hole 2g, and the ball receiving portion 2h has a ball so that a gap is partially formed between the ball receiving portion 2h and the ball 3. 3 is rotatably held.

A coil spring 4 constituting the tip 1 as shown in the figure is inserted into the holder 2 from the rear and loaded therein. That is, the tip of the coil spring 4 has a linear extension 4a extending forward along the axis of the holder 2, and the extension 4a reaches the ball 3 through the ink guide hole 2g. The distal end surface of the extending portion 4 a contacts the ball 3, biases the ball 3 forward, and a part of the ball 3 is exposed from the distal end opening of the holder 2.
In this case, the ball 3 is about 35% to 40% of its diameter.
Is best exposed.

On the other hand, a step portion 4c is formed by providing a large-diameter end turn portion 4b at the rear end portion of the coil spring 4, and the rear end portion of the end turn portion 4b is a rear end caulking portion of the holder 2. 2j is locked and stored. Although a gap is partially formed between the ball 3 and the holder 2, the ball 3 may fall from the tip caulking portion 2 of the holder 2 because the tip caulking portion 2 i of the holder 2 is formed. Absent. As described above, the coil spring 4
The tip is a straight line extending forward along the axis of the holder 2 .
It has an extension 4a.

As is apparent from FIGS. 3 and 4, the ink guide hole 2g has a plurality of branch holes 2gg each having a radial cross section from the center hole so that the ink can smoothly flow in relation to the ball 3. Is formed.

Strictly speaking, the distal end surface of the extension 4a of the coil spring 4 is flat, while the ball 3
Are spherical, so they are in point contact with each other. Then, in this state, the ball 3
Since the inside of i is urged forward to completely contact and abut against the entire inner periphery of the caulking portion 2i, there is an advantage that there is no danger of ink leakage when carrying the device in a state where it is mounted on a refill as described later. is there.

The rear end of the coil spring 4 is formed with an end turn 4b having a larger diameter than the intermediate pitch.
The rear end portion of the holder 2 corresponding to the end turn portion 4b is formed with a rear end caulking portion 2j to lock the rear end of the coil spring 4. By making the outer diameter of the end winding portion 4b large, there is an advantage that the locking action of the coil spring 4 can be sufficiently obtained even if the degree of caulking of the rear end caulking portion 2j of the holder 2 is small.

It is important that the gap between the coils constituting the spring when the spring is free is made smaller than the wire diameter of the spring.
Specifically, the wire diameter of the coil spring 4 is 0.1 m.
In the range of m to 0.2 mm, the pitch at the time of the spring free length is set to 1.5 to 1 times the wire diameter of the coil spring 4.
The coil spring 4 is set to a tip 1 with a pitch 9 times as large as that of the tip 1.
Caulking behind the ball 3 inside. Further, the coil spring 4 which is locked by the caulked portion 2j at the rear end of the intermediate pitch portion of the coil spring 4 beyond the outer diameter
There is also an advantage that the outer diameter of the rear end winding portion 4b is increased to enable automatic alignment.

FIG. 5 is a longitudinal sectional view showing a state in which the tip 1 is mounted on a ballpoint pen refill. For example, reference numeral 5 denotes a refill filled with a gel-like ballpoint pen ink, and a tip 1 is fixed to the tip of a front small diameter portion 5a of the refill 5 by press-fitting.

On the other hand, an opening is formed in the rear part of the refill 5, and a tail plug 6 having a small hole 6a for air circulation is attached to the opening at the rear end. Further, there is provided a backflow preventing member 7 made of polybutene or the like which is in contact with the rear end face of the ink filled in the refill 5 to prevent backflow of the ink. The backflow prevention member 7 moves following the consumption of the ink, and moves down together with the ink to prevent the backflow of the ink.

FIG. 6 is a longitudinal sectional view showing a knock type ball-point pen in which the ball-point pen refill 5 is further assembled to the barrel 8. In the figure, a refill 5 is provided with a locking portion 8a formed on the inner periphery of the front part of the barrel 8 and a shoulder 5b of the refill 5.
Are urged to the rear of the barrel 8 by a return spring 9 mounted between them.

Therefore, when the knock portion 11 is knocked in use, the refill 5 is advanced against the return spring 9 so that the tip of the tip 3 protrudes from the opening of the shaft cylinder 8 and is provided on the back side of the tip of the clip 10. The locking projection 10a is locked by a stopper 8b provided on the outer wall of the barrel 8, and the writing state is established.

After the writing is completed, when the rear end of the clip 10 is pushed or the front end of the clip 10 is lifted to remove the locking projection 10a from the stopper 8b of the barrel 8, the refill 5 is urged against the return spring 9. The tip of the tip 1 is retracted and returned to the initial position, and the tip of the tip 1 is stored in the barrel 8.

That is, in the tip 1 of the ball type liquid container thus configured, the ball 3 is inserted into the tip in advance, and the ball 3 is held by the tip caulking portion 2i in which the periphery of the tip opening is swaged. ing. A large number of such tip chips 1 are set upright on a turntable, and the coil springs 4 suspended in sequence with the end turns 4b facing upward are positioned according to the rotation of the turntable and set in the holder 2. Then, the rear end of the holder 2 is caulked, and the unitized tip chip 1 is easily completed by automation.

[0024]

Since the present invention has the structure described above, the ball pressing portion and the coil spring are integrated into a unit to structurally form the tip end, and each coil constituting the spring when the spring is free length. The gap between the springs is made smaller than the wire diameter of the springs to eliminate entanglement between the springs, and the end turns of the rear end springs to be caulked in the tip of the ballpoint pen are made larger than the outer diameter of the intermediate pitch portion. Thus, the direction of the spring can be aligned in the direction of the neck fishing, so that there is an effect that the assembly can be dependent on the automatic machine.

Further, the present invention provides a low viscosity to a high viscosity (3.5 cps to 5,000 c at 20 ° C.) for writing.
ps) In a knock-type or cap-type writing implement using ink of the type described above, the above spring is attached to the back of the ball in the tip of the ballpoint pen to prevent leakage of the ink tip and to dry up the ink around the ball when writing is not performed. It has the effect of preventing.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a tip of a ball type liquid container according to an embodiment of the present invention.

FIG. 2 is an enlarged longitudinal sectional view showing a distal end portion of the distal end tip of FIG. 1 from which a coil spring is removed.

FIG. 3 is a transverse sectional view taken along line AA of FIG. 2;

FIG. 4 is a bottom view showing the state without the ball of FIG. 2;

FIG. 5 is a longitudinal sectional view showing a state where the tip of FIG. 1 is attached to a ballpoint pen refill;

6 is a longitudinal sectional view showing a ballpoint pen in which the ballpoint pen feel of FIG. 5 is assembled to a barrel.

FIG. 7 is a longitudinal sectional view showing a tip of a conventional ball type liquid applicator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tip 2 Holder 2a Pen tip 2b Thin part 2c Step 2d First step 2e Second step 2f Third step 2g Ink guide hole 2gg Branch hole 2h Ball receiving part 2i Tip swaging part 2j Rear swaging part Reference Signs List 3 Ball 4 Coil spring 4a Extension 4b End turn 5 Refill 5a Small diameter portion 5b Shoulder 6 Tail plug 6a Small hole 7 Backflow prevention member 8 Shaft 8a Locking portion 8b Stopper 9 Return spring 10 Clip 10a Locking protrusion 11 Knock part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B43K 1/08 B43K ^7/ 00-7/12

Claims (3)

(57) [Claims] 1. A tip tip of a ball type liquid container in which a coating ball is rotatably held at a tip of a holder, a coil spring which is bent by writing pressure in the holder, and a tip of the coil spring . Is the above holder
Linearly extending portion through the liquid induction hole in the holder tip in pressure contact with the ball, and the rear end of the holder by caulking to form a caulked portion, and the coil extending forwardly along the axis of A tip end of a ball type liquid container, wherein a step portion is formed by increasing the outer diameter of a rear end turn portion of a coil spring to be caulked and attached to the outer diameter of an intermediate pitch portion constituting a spring. 2. The tip of a ball type liquid container according to claim 1, wherein the gap between the coils constituting the spring when the spring is free length is smaller than the wire diameter of the spring. 3. The method according to claim 1, wherein the spring has a wire diameter in a range of 0.1 mm to 0.2 mm, and a pitch in a free length of the spring is 1.5 to 1.9 times the wire diameter of the spring. 3. The tip of a ball type liquid container according to claim 2, wherein