JPH10217669A - Refill for ball point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a direct flow and a reverse flow of ink by pressing the rear end of a tip ball on the end of a bar shaft section, bringing the tip end ball into contact with the inner edge of a ball holding section on the tip end and also forming combinedly an ink backflow prevention section or the axial center of a joint at the back of the tip. SOLUTION: When a tip 12 is faced upward, a discharge hole 9 of a valve chamber 6 is closed by a ball valve 10, and ink is covered by a head when ink right below a tip end ball 12a is run out to prevent a reverse flow. When the tip 12 is faced downward, the ball valve 10 is moved eccentrically to one side of the rear end of a caulking section 15 of the tip 12, and ink 18 passed through the discharge hole 9 and introduced into the valve chamber 6 is guided to the rear end of the tip end ball 12a through a channel 8. The tip end ball 12a is brought into contact with the inner edge of a tip wrapping section by the pressure of a bar shaft section 16a to prevent a direct flow of ink, and the tip end ball 12a is moved back slightly by the writing pressure to form a clearance and the ink is flowed out by the rotation of the tip end ball 12a to perform the writing without blotting and blurs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a refill of a ball-point pen in which a writing tip is mounted on a barrel so as to be freely retractable, using an aqueous ink having a shear thinning property and an oil ink mainly having a low viscosity. The present invention relates to direct current and backflow prevention of the ink in the case of the above.

[0002]

2. Description of the Related Art The applicant of the present invention discloses, in Japanese Utility Model Publication No. 4-52067, a mechanism for preventing backflow of ink of a ballpoint pen provided with a valve chamber into which a ball is loosely fitted. In this case, a required number of protrusions are provided in a valve chamber in which a ball is loosely fitted with a synthetic resin mouth plug to prevent the ball from being pulled out, and a gap formed between the protrusions at the time of writing. And the ink flows to the chip. Further, conventionally known oil-based ballpoint pen inks have a high viscosity and a small amount of ink flows out by rotation of the tip ball during writing. In addition, there are problems such as unevenness, unevenness of writing lines, low density, and high writing pressure.
Also, as an improvement of the conventional oil-based ballpoint pen, it is a relatively low-viscosity ink. Are known. However, since this ink has a drawback that the ink is easily dried, a cap for sealing the writing tip is required. Therefore, a low-viscosity oil-based ink with excellent drying resistance is conceivable. However, the amount of ink flowing out is also large, and the diameter of the ink storage tube is increased to increase the writing life, thereby increasing the amount of installed ink. . The same applies to the above-mentioned water-based ink. However, since the viscosity of the ink is smaller than that of the conventional oil-based ballpoint pen ink, the flow resistance to the ink storage tube is small. Accordingly, ink leakage (ink flows backward at the rear end of the ink storage tube) easily occurs due to the ink's own weight or impact. For this purpose, a grease-like follower is provided at the rear end of the ink, which normally moves following the consumption of the ink during writing, but suppresses the backflow of the ink against its own weight or impact. However, even when the follower is provided, when ink is written immediately below the tip ball when writing upwards, there is a danger that the ink or the head will be added directly, causing a remarkable backflow and soiling hands and clothes. In addition, since the viscosity of the ink is low and the amount of outflow is large, if the tip side faces downward and a gap is formed between the tip ball and the tip holding portion, the ink may bleed (direct current). Further, there is a problem that the ink immediately below the tip ball tends to flow backward after upward writing or after an impact such as knocking or dropping, so that writing blur occurs. In addition, there is a risk that the clothes may be soiled if the writing tip is inserted into a breast pocket or the like with the writing tip protruding.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a ballpoint pen refill using a water-based ink having a shear-thinning viscosity or a low-viscosity oil-based ink. It is mounted on a knock-type ballpoint pen to prevent direct current of ink, knock, drop impact, backflow of ink for upward writing, and to prevent contamination of the shaft, hands, clothes, etc. . Also, upward writing, to prevent writing blur caused by running out of ink due to air entrapment just below the tip ball when an impact is applied,
It is possible to prevent handwriting from occurring due to drying caused by incomplete sealing between the tip ball and the inner edge of the tip holding portion.

[0004]

SUMMARY OF THE INVENTION The ballpoint pen refill of the present invention devised to achieve the above object has a rotating operation of a barrel, a knocking operation which is well known in a Kern type knocking mechanism, and a clip end when knocking. And a writing mechanism, such as a knock mechanism with a safety mechanism that unlocks the writing tip when the clip is inserted into the chest pocket and the writing tip is immersed in the shaft. The ball-point pen is mounted on the ball-point pen so that the writing tip can be protruded and retracted from the tip of the shaft by changing the refill of the ball-point pen with respect to the barrel. An ink storage tube is provided at the rear, and the ink storage tube is filled with an aqueous ink having a shear-thinning viscosity or a low-viscosity oil-based ink, and the rear end of the ink is filled with ink as the ink is consumed. Click and follow suit follower is disposed,
An upright bar shaft is formed at the tip of the spring in the inner hole of the tip, or a pusher with a bar shaft is provided at the front end of the spring, and the tip of the bar shaft is the rear end of the tip ball. The tip ball is pressed closely to the inner edge of the ball holding portion at the tip of the tip to prevent direct current and backflow of ink, and an ink backflow prevention portion is also provided at the axis of the joint behind the tip. With the writing pressure, the close contact between the tip ball and the inner edge of the ball holding portion of the tip is released, and the ink can flow out with the rotation of the tip ball. By preventing the ink from flowing backward by writing, it is possible to prevent contamination of the hand, the inside of the barrel, and clothes, and to prevent writing blur.

[0005]

1 to 3 show a first embodiment of a ballpoint pen refill mounted on a knock-type ballpoint pen according to the present invention. First, FIGS. 1 and 2 show a refill 1 of a ballpoint pen according to the present invention. The joint 2 has a front shaft portion 3 formed in front of a flange-shaped step portion 4 and a rear shaft portion 4 formed rearward, and a tip 12 holding a tip ball 12 a in an inner hole portion 11 at the front end of the front shaft portion 3. Is fixedly mounted. The inner hole 11 is formed by chip fitting holes 11a and 11b from the front, and a convex locking portion 14 is formed on the outer periphery of the shaft portion 13 of the chip 12 as necessary, and bites into the chip fitting hole 11b. It is locked in a shape.

The tip 12 is caulked so that the tip ball 12a is rotatably held with the tip ball 12a substantially in contact with a seat having a channel 12b into which ink can flow. A spring 1 is provided in the inner hole of the tip 12.
6 is inserted, the rear end of the shaft portion 13 of the chip is appropriately caulked, and the rear end of the spring 16 is provided so as not to be pulled out.

An upright bar shaft 16a is formed in front of the spring 16, and the front end of the bar shaft 16a presses against the rear end of the ball 12a. The tip ball 12a is brought into close contact with the inner edge of the ball holding portion (formed by caulking or the like) of the chip 12 by the pressing.

Further, as an ink backflow preventing portion, an inner hole portion 1 is provided.
A valve chamber 6 which is appropriately eccentric with respect to the axis of the chip 12 is provided at the rear of the tip 1, and a tapered or spherical ball receiving seat 7 is formed at the rear of the valve chamber 6 so as to communicate with the guide hole 9. A groove 8 into which ink can flow is formed on one side of the inner wall of the valve chamber 6. Further, the ball valve 10 is loosely fitted in the valve chamber 6, and the ball valve 10 abuts against the rear end of the shaft portion 13 of the chip with the chip 12 facing downward. The ink flowing from the guide hole 9 through the hole or the like flows into the chip inner hole.

A rear shaft 5 is provided behind the step 4 of the joint 2.
Is extended. A cylindrical ink storage tube 17 is press-fitted and fixed to the outer periphery of the rear shaft portion 5 with its front end abutting on the rear end of the step portion 4, and the inner diameter of the ink storage tube 17 is conducted to the guide hole 9 of the joint 2. I have. The ink container 17 is filled with an ink 18 of an oil-based ball-point pen having excellent drying resistance, and a grease-like shape is provided at the rear end of the ink 18 that can move following the ink surface as the ink is consumed. Follower 19 is filled. The ink container 17 is made of, for example, a transparent PP resin molded product.

On the other hand, FIGS. 4 to 6 show examples of a knock type ballpoint pen. Basically 4-5398
Since it is the same as the knock-type writing instrument of JP-A-7, only the main points and differences will be described below.

A clip 21 having a mounting leg 22 provided with a slit 30 on a side surface facing the clip 21 and grooves 23 connected to both sides of the slit 30 and communicating with the slit 30 is integrally formed with the shaft cylinder 20. A ball portion 24 is formed at the distal end of the clip 21, and the ball portion 24 is provided with a hooked locking step 25 and a side wall 26. Clip 21
Is a locking projection 33 of the knocking body 31 and a locking step 25 described later.
Is elastically displaceable in the lateral direction by a distance that can be disengaged. The slit 3 is provided on the side surface of the barrel 20.
A window hole 27 is provided separately from 0. The shaft cylinder 20 is formed of a transparent resin molded product containing the above-described polyester resin.

The knocking body 31 has a locking projection 3 on its side.
3, a stopper piece 32 is provided on a coaxial line, and a locking projection 34 is provided on an axis different from the locking projection 33 so as to be elastically displaceable.

The ballpoint pen refill 1 is inserted into the bore of the barrel 20 with the rear end of the coil spring 35 abutting the step 4, and the tip of the coil spring 35 is inserted into the inner step 28 of the barrel. The knock body 31 is attached in a state where the rear end of the refill 1 of the ball-point pen is housed from the rear end of the barrel 20. The locking projection 33 and the stopper piece 32 of the knock body 31 pass through the groove 23 so that the locking projection 33 protrudes through the slit 30, and the stopper piece 32 is attached to the mounting leg 22.
Located in the groove 23 inside. At this time, the locking projection 34 protrudes from the rear end portion of the window hole 27 of the shaft cylinder, and the knocking body 31 is prevented from falling out in a state of being urged rearward.

FIG. 7 shows a second embodiment of the refill of a ball-point pen. Hereinafter, only differences from the first embodiment will be described. First, the joint 40 is integrally formed of an elastically deformable synthetic resin, and a valve chamber 41 is provided on the rear side in communication with the chip fitting hole 49. Also, valve room 4
1 has a tapered or spherical ball seat 42 at the rear end.
A required number of ridges 43 are provided on the front peripheral wall of the valve chamber 41.
Is provided.

A ball seat 42 is provided behind the valve chamber 41.
A ball valve 46 is elastically deformed in the valve chamber 41 and elastically deforms the ridge 43 so that the ball valve 46 cannot be pulled out and is loosely fitted. Note that an ink guide groove is formed between the ridges with which the ball valve 46 contacts. Also, the rear end of the spring 48 abuts the step 45 at the front end of the ridge 43, and the rod shaft 48
The tip of a presses the rear end of the tip ball 47a.

As described above, when the tip side is downward, the ball valve 46 comes into contact with the rear end of the ridge 43,
Ink flows through the guide hole 44, the valve chamber 41, the ink guide groove between the ridges and the inner hole of the tip 47, and the tip ball 47a.
To the rear end.

FIG. 8 shows a third example of a ballpoint pen refill.
Is shown. Since it is basically the same as the first embodiment, only the differences will be described below. A front end of a spring 55 inserted into the chip 47 forms a seat, and a pushing body 54 having a rod shaft portion 54a is disposed at a front portion thereof, and a front end of the rod shaft portion 54a is a rear end of the tip ball 47a. Abuts on the pressing member.

FIG. 9 shows a fourth example of a ballpoint pen refill.
Is shown. Since it is basically the same as the first embodiment, only the differences will be described below. An upright rod portion 48a is formed at the front end of the spring 48. or,
It may be provided with a tapered winding portion along a tapered inner hole in front of the tip 47. Furthermore, since the inner hole of the chip is usually formed with a stepped drill hole, the chip is formed in a spring having a step-shaped winding portion reduced in a step shape along the step hole. There is also.
In some cases, the forefront end of the winding portion is brought into contact with the tip ball. (Not shown) In the refill of the ballpoint pen in the above-described embodiment, the joint and the ink storage tube are formed by separate members, but both may be formed by an integral resin molded product.

[0019]

First, in a first embodiment of the ballpoint pen refill, FIG. 1 shows a state in which the tip 12 is turned upward, and at this time, the ball valve 10 is connected to the ball receiving seat 7 of the valve chamber 6.
And seals the guide hole 9, so that even if the ink is written upward and the ink immediately below the tip ball 12a of the chip runs out,
There is no backflow due to the head hanging on the ink. Therefore,
When the tip 12 is turned downward, the ink can immediately flow out, and writing is prevented from being skived. (By the way, in the structure without the ball valve, the ink acts in the backward flow direction in the upward writing, so that air is entrapped in the chip, and the ink does not immediately follow in the downward writing, resulting in rubbing.)

As shown in FIG. 2, in a writing state in which the chip 12 is directed downward, the ball valve 10 abuts on one of the rear ends of the caulking portion 15 of the chip, and the other side has the inside of the chip 12. A groove 8 through which ink can flow is formed, and the ink 18 that has entered the valve chamber 6 from the ink storage tube 17 through the guide hole 9 passes through the groove 8 and is guided to the rear end of the tip ball 12 a of the chip 12.

In this state, the tip ball 12a is brought into close contact with the inner edge of the tip holding portion by the pressing of the rod shaft portion 16a, so that the direct current of ink is prevented. In addition, the tip ball 12a is slightly retracted by the writing pressure, so that a gap is generated and ink can flow out. By writing, a large amount of ink flows out by rotation of the tip ball 12a, and writing with high density can be performed without burrs. Become.

A channel 12b (a seat for the tip ball having a plurality of ink inflow grooves penetrating toward the inner hole of the chip) is provided immediately below the tip ball 12a. 16a penetrates. The ink in the chip is filled with the ink inflow groove and the center hole and the rod shaft portion 16a.
Is guided directly below the tip ball 12a through a gap between the front ball 12a and the front ball 12a.

Next, in a second embodiment of the ballpoint pen refill, FIG. 7 shows a state in which the tip 47 is directed upward, at which time the ball valve 46 comes into close contact with the ball receiving seat 42 of the valve chamber 41. Since the guide hole 44 is sealed, the ink does not flow backward even when the ink immediately below the tip ball 47a runs out by upward writing. With the tip 47 facing down,
The ball valve 46 comes into contact with the rear end of the ridge 43, and the guide hole 44 is opened. The ink that has entered the valve chamber 41 from the ink storage tube 4 through the guide hole 44 passes through the ink guide groove formed between the ridges and is guided to the rear end of the tip ball 47a. Other operations are the same as those of the first embodiment.

In the first embodiment, there is no ridge for contacting the ball valve so that it cannot be pulled out as in the second embodiment.
The mold accuracy and molding conditions for molding the mold become easier. (Incidentally, dimensional accuracy is difficult to obtain because the ridges are undercut due to mold release.) Also, it becomes easy to insert and insert the ball valve into the valve chamber. (There is a problem that the ridge is damaged because it is inserted.) This is advantageous for a mechanical assembly. However, in the first embodiment, it is necessary to caulk the rear end of the chip 12 in order to make the spring 16 unable to be pulled out, and it can be said that it is more disadvantageous in processing time than the second embodiment.

Since the third and fourth embodiments of the ballpoint pen refill are basically the same as the first embodiment, only the essential points will be described. First, in the third embodiment, as shown in FIG. 8, a separate pressing body 54 is provided at the front end of the spring 55, so that the rod shaft portion 54a has good swingability, and the friction of the portion that comes into contact with the tip ball 47a. You can select the resistance (material and shape), so the writing feel is good. Further, in the fourth embodiment, as shown in FIG. 9, since the rod shaft portion 48a is provided integrally with the winding portion of the spring 48, it is advantageous in cost. In addition, by providing a tapered or stepped winding portion along the inner hole portion of the tip 47 to stabilize the axial center of the rod shaft portion, the bias of ink induction and the contact resistance with the tip ball are reduced. Stabilize.

Further, since the tip ball 47a is always in close contact with the inner edge of the tip holding portion, the writing at the tip portion is prevented from being scribbled. Further, the third and fourth embodiments are inferior to the first and second embodiments, because the backflow prevention portion of the ink is not provided, and the air entrapment may be accumulated by repeated upward writing. Even when upward writing or impact is applied, the entrainment of air is appropriately prevented by the cooperative action of the tip ball 47a, the appropriate composition of the ink and the follower, and it is possible to prevent the backflow of ink and the writing blurring in practical use.

FIG. 4 shows a state in which the refill 1 of a ball-point pen is housed in the barrel 20. When the rear end of the knock body 31 is knocked and advanced, the locking projections 33 make the locking step of the clip. 25 as shown in FIG.
Is projected from the shaft tip port 29. In this state, when the distal end portion of the clip 21 is elastically displaced in the lateral direction on the side having the side wall 26, the locking projection 33 is disengaged from the locking step 25 and returns to the state shown in FIG. When the clip 21 is inserted into a breast pocket or the like in the state shown in FIG. 5, the engagement step 25 is pushed upward, so that the engagement with the engagement projection 33 is released, and the tip 12 is inserted into the shaft cylinder from the shaft tip opening 29. Immerse yourself. Therefore,
There is no need to worry about soiling clothes even if the chip is accidentally inserted into a pocket or the like with the tip protruding. When replacing the refill 1 of the ball-point pen with a new one, if the locking projection 34 of the knock body 31 is pushed inward, the engagement between the locking projection 34 and the window hole 27 of the barrel is released, and the knock body 31 is disengaged. It is possible to take out the refill 1 of the ball-point pen together with 31.

[0028]

The configuration and operation of the refill of the ballpoint pen according to the present invention are as described above, and there is no bottling, a thick drawn line, and a non-uniformity using an aqueous ink having a shear thinning property or an oily ink mainly having a low viscosity. It is possible to provide a refill of a ball-point pen that is mounted on a knock-type ball-point pen that does not require a cap and that does not require a cap. In addition, since the ink is prevented from flowing back due to direct current, upward writing, knocking and impact of the ink due to the low viscosity ink, an accident that stains the inside of the shaft cylinder, hands, and clothes is prevented. In addition, handwriting is prevented. In addition, since the tip ball is in close contact with the inner edge of the chip holding portion except during writing, there is an effect of preventing writing blur due to drying over time. In addition, if the clip is inserted into a breast pocket or the like with the writing tip protruding, the writing tip automatically sinks into the barrel so that there is no danger of soiling the clothes.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an entire refill of a ballpoint pen according to a first embodiment of the present invention, showing a state in which a chip is directed upward.

FIG. 2 is an enlarged cross-sectional view of a main part of a refill of the ballpoint pen according to the first embodiment, showing a state where a chip is directed downward.

FIG. 3 is an enlarged cross-sectional view of a valve chamber portion in the first embodiment.

FIG. 4 is a partially non-sectional longitudinal sectional view showing an example of a knock-type ball-point pen on which a refill of a ball-point pen is mounted, showing a state in which a writing tip is immersed.

5 is a partial non-sectional longitudinal sectional view corresponding to FIG. 4, showing a state in which a writing tip is protruded.

FIG. 6 is a top view corresponding to FIG. 4;

FIG. 7 is an enlarged sectional view of a main part of a refill of a ballpoint pen according to a second embodiment, showing a state in which a chip is directed upward;

FIG. 8 is an enlarged sectional view of a main part of a refill of a ballpoint pen according to a third embodiment, showing a state in which a chip is directed upward.

FIG. 9 is an enlarged cross-sectional view of a main part of a refill of a ballpoint pen according to a fourth embodiment, showing a state where a chip is directed upward;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ballpoint pen refill 2 Joint 3 Front shaft part 4 Step part 5 Rear shaft part 6 Valve room 7 Ball receiving seat 8 Groove part 9 Guide hole 10 Ball valve 11 Inner hole part 11a Chip fitting hole 11b Chip fitting hole 12 Tip 12a Tip Ball 12b Channel 13 Shaft portion 14 Locking portion 15 Caulking portion 16 Spring 16a Bar shaft portion 17 Ink storage tube 18 Ink 19 Follower 20 Shaft tube 21 Clip 22 Mounting leg portion 23 Groove 24 Ball portion 25 Locking step portion 26 Side wall 27 Window Hole 28 Inner surface step 29 Shaft tip opening 30 Slit 31 Knock body 32 Stopper piece 33 Locking projection 34 Locking projection 35 Coil spring 40 Joint 41 Valve chamber 42 Ball receiving seat 43 Projection 44 Guide hole 45 Step 46 Ball valve 47 Tip 47a Tip Ball 48 Spring 48a Bar Shaft 49 Tip Insert Mounting hole 50 Joint 51 Chip fitting hole 52 Step 53 Conducting hole 54 Pressing body 54a Bar shaft 55 Spring

Claims (1)

[Claims] 1. A refill of a ball-point pen mounted on a knock-type ball-point pen capable of moving a writing tip portion from a tip end of a shaft while moving relative to a shaft cylinder, wherein the refill of the ball-point pen is attached to a tip of a joint. A follower that has an ink container tube behind the tip of the ballpoint pen and is filled with water ink having shear thinning viscosity or mainly low-viscosity oil-based ink, and the trailing end of the ink follows the ink as the ink is consumed. Is disposed, and an upright bar rod is formed at the tip of the spring in the inner hole of the tip, or a push body having a rod rod is provided at the front end of the spring, and the tip of the rod shaft is By pressing the rear end of the tip ball, the tip ball is brought into close contact with the inner edge of the ball holding portion at the tip of the tip to prevent direct current and backflow of ink, and furthermore, into the axis of the joint behind the tip. A backflow prevention part is also installed,
A refill for a ballpoint pen, wherein the close contact between the tip ball and the inner edge of the ball holding portion of the tip is released by writing pressure so that ink can flow out as the tip ball rotates.