JPH10100588A - Dual writing instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To guarantee smooth protruding or retracting of a writing tip by inserting an ink containing tube into a barrel without oscillating as a non- deforming shape, and providing a bendable front barrel between its front end and the tip in a dual writing instrument having several types of writing units selectively protruding or retracting by rotation of an actuator. SOLUTION: When an actuator 34 is rotated in one direction to a barrel 30, sliding protrusions 6a, 6b of ball point pen writing units 1a, 1b are slid along spiral grooves 42, and any one unit 1a is moved forward, its writing end (tip) 11 is protruded from an end port of the barrel 30. At this time, ink containing parts of the units 1a, 1b are inserted into the barrel 30 as non- deforming shapes, and a bendable front barrel is coupled between its front end and the tip 11. Accordingly, the tip 11 can be smoothly protruded from or retracted to the port without disturbing its operation. A ball of a clip 38 is engaged with a swell part 33 in the state that the tip 11 is protruded so that the clip is not inserted into a breast pocket.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved writing instrument having a plurality of ballpoint pen writing bodies.

[0002]

2. Description of the Related Art In general, there is known a double-type writing instrument equipped with a plurality of writing objects such as a mechanical pencil and a ball-point pen so that the writing tip can be selectively protruded and retracted from an axis.

A water-based ballpoint pen has a viscosity of several mPa ·
Since it has a low viscosity of S or less, it is advantageous to be able to write with a light writing pressure, and has a characteristic that writing quality is good. However, there is a drawback that a DC phenomenon in which the ink flows slowly from the pen tip, and a reverse flow phenomenon in which the air flows in from the tip of the ballpoint pen and the ink flows out, are likely to occur. A method of preventing these phenomena by using a fiber convergence material called batting is used.

On the other hand, conventionally known oil-based ball-point pens have a high viscosity of several thousands mPa · S or more of the ink used for the ball-point pens, so that the resistance to the rotation of the ball when the ink flows out of the pen tip is high. There is a drawback that writing is bad because of large size. In addition, there is a problem in that the amount of ink flowing out from the tip during writing is small, there is a dent phenomenon, the writing line is uneven, the writing density is low, and a high writing pressure is required.

As an improvement of the oil-based ballpoint pen, recently,
A ballpoint pen for water-based ink called a medium viscosity using an ink having an intermediate viscosity region between water and oil (several mPa · S to several thousand mPa · S) has been developed. This is a ballpoint pen using a relatively low-viscosity water-based ink having a characteristic of lowering the viscosity by the rotation of the tip ball and smoothly flowing out the ink, that is, a so-called shear thinning property. Further, as an improvement of the oil-based ball-point pen, a ball-point pen using a low-viscosity oil-based ink having excellent drying resistance can be considered.

The ballpoint pens using the medium-viscosity water-based ink and the low-viscosity oil-based ink are all low-viscosity, so that when the tip side is turned downward, a gap between the tip ball and the chip holding portion is generated. There is a phenomenon in which the ink tends to flow backward due to a direct current problem in which ink bleeds, upward writing, impact, or the like. If the ink causes backflow or direct current, there is a risk of soiling clothes and the like. In addition, when mounted on a writing instrument and inserted into a breast pocket or the like with the writing tip protruding, there is a problem in that clothes are soiled.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a mechanism capable of maintaining a dry end of a writing tip, allowing a seal cap to be removed and leaving the seal cap, and preventing direct current or backflow of ink. It has a medium-viscosity water-based, low-viscosity oil-based ballpoint pen writing body, and has a large number of ballpoint pen writing bodies that have a large ink container and are non-deformable. In addition, the writing tip can be inserted into a breast pocket or the like with the writing tip protruding, so that the protruding state of the writing tip can be easily recognized, and there is no fear of soiling clothes etc. And can be provided at low cost.

[0008]

According to the present invention, there is provided a double-type writing instrument in which a plurality of ballpoint pen writing bodies are mounted in a barrel, and each of the writing tips can be selectively protruded and retracted from the tip end of the barrel. An operation body fixed to the shaft cylinder so as to be rotatable only, and a sliding protrusion integrally provided on a cam slope provided on an inner periphery of the operation body at substantially a rear end of ink storage of a ballpoint pen writing body. And the ball-point writing body is provided so as to be movable only in the axial direction with respect to the barrel, and each ball-point writing body can be moved back and forth by rotating the operating body with respect to the barrel. The ink storage portion of the ballpoint pen writing body is substantially non-deformable and is inserted without swinging into the shaft, and has a long front shaft that can be flexibly bent between the front end of the ink storage portion and the writing tip. Part is provided, the front shaft part protrudes behind the tip end of the barrel The partition portion is provided has made a return spring for biasing the respective ball-point pen cursive rearwardly between the front end of the partition portion and the ink accommodating portion is disposed.

In addition, a clip having a base fixed to one side surface of the operating body and disposed toward the front of the barrel, and a ball provided with a locking portion at the forward end of the clip are provided. A bulging portion provided with a locking portion is provided at a predetermined position on the peripheral surface of the barrel that is in contact with the clip, and only when the operating body is rotated so that the writing tip protrudes from the tip end of the barrel, the clip is removed. The locking portion of the ball portion and the bulging portion are engaged with each other so that the ball portion of the clip does not separate from the surface of the shaft cylinder.

[0010] In the ballpoint pen writing body, the tip ball always presses the inner edge of the ball holding portion at the tip of the tip to come in close contact therewith.
An aqueous ballpoint pen ink having a so-called shear-thinning property, which has a spring provided so that the close contact state is released at the time of writing, and the viscosity is reduced and flows out by the rotation of the tip ball accompanying the writing into the ink storage portion. The ink is filled with a low-viscosity oil-based ink, and the rear end of the ink is filled with a follower made of a grease-like translucent non-drying substance that moves following the consumption of the ink during writing. Also, the ballpoint pen writing body is provided with a valve chamber in which a ball valve is loosely fitted, facing the rear end of the chip. The ball valve is in close contact with the rear of the valve chamber, and the ball receiving seat prevents the backflow of ink. And a guide hole communicating with the inside of the ink container.

[0011]

1 to 6 show an embodiment of the present invention. In FIG. 1, two ballpoint pen cursives 1a,
1b is provided. The dual writing implement intended by the present invention is a ballpoint pen writing medium filled with a so-called middle viscosity aqueous or low viscosity oily ballpoint pen ink having a shear thinning property, or a normal oily ballpoint pen writing body equipped with a large volume of ink. Are used in combination as needed.

First, a ballpoint pen writing body mounted on the double-type writing instrument of the present invention will be described. Note that the ballpoint pen writing bodies 1a and 1b have the same configuration, and have different ink colors, for example. Further, the ink applied to the ballpoint pen writing material is mainly a medium-viscosity aqueous and low-viscosity oil-based ink having a so-called shear thinning property.

The tip 11 is caulked so that the tip ball 12 is rotatably held with the tip ball 12 substantially in contact with a seat having a channel into which ink can flow. Further, the spring 14 is inserted into the inner hole of the chip 11, and the rear end of the chip is appropriately caulked so that the rear end of the spring 14 cannot be pulled out. In addition, it is extremely important that the tip ball 12 is in close contact with the inner surface of the tip holding portion in order to dry the writing tip and to prevent direct current of ink. Therefore, the surface roughness of the tip holding the tip ball and the caulking In order to improve the close contact accuracy, grinding of the inner surface and secondary plastic working to increase the crimping accuracy are considered. or,
The surface treatment etc. are considered in the close contact surface with the tip ball.
Further, the tip of the spring 14 becomes a straight rod shaft portion 15, and the tip of the rod portion 15 comes into contact with the back surface of the tip ball 12 in a pressed state. In addition, the tip ball 12 is pressed by the pressing to
The first ball holding portion (formed by caulking or the like) is in close contact with the inner edge.

The cylindrical body 2 is formed by a long front shaft portion 3 for pressing the tip 11 to the tip and an ink container 4, and the front shaft portion 3 is formed of a resin molded product that can be flexibly bent.
Further, a valve chamber 7 in which a ball valve 16 is loosely fitted is provided in a front end inner hole of the front shaft portion 3 so as to face the rear end of the chip 11,
When the tip 11 is downward, the guide hole 9 is opened and the ink 18 is conducted to the tip side. On the contrary, when the tip 11 is upward, the ball valve 16 closes the guide hole 9 to prevent the ink from flowing back. .

By the way, the cross section of the ink container 4 is substantially D
It has a shape (FIG. 6), and has a substantially circular shape in a state where the two flat portions are in contact with each other. In the case of three ink containers, the cross section of the ink storage tube is formed in a substantially fan shape obtained by dividing a circle into 120 degrees. The ink container 4 is filled with the above-mentioned medium-viscosity water-based or low-viscosity oil-based ink, and the rear end of the ink is in the form of a grease that can follow the ink surface and move following the consumption of the ink. Is filled with a follower 18 made of a translucent non-drying material. In the follower 18, a resin follower rod 19 having a specific gravity substantially equal to that of the follower is immersed.

An axially integral guide rib 5a is formed on the outer periphery of the rear side of the ink container 4, and a slide protrusion 6a is formed at the rear end of the guide rib 5a. The sliding projection 6a has a cam slope on its rear end side that comes into sliding contact with a cam slope of an operation body described later. Further, in the embodiment, the sliding protrusion 6a and the guide rib 5a are provided integrally with the ink container 4, but it is also possible to fasten to the ink container as a separate member. Thus, the ballpoint pen writing body 1a is configured. In addition, ballpoint pen writing body 1b
Is similarly configured.

The double-type writing instrument shown in FIG. 1 includes two types of ballpoint pen writing bodies, a shaft cylinder 30 for storing the ballpoint pen writing bodies,
It comprises a tubular operating body 34 fixed to the rear of the barrel 30 so as to be rotatable only. The operating body 34 is detached from the barrel 30 as necessary, and the writing body is replaced. It is also possible to make the shaft cylinder 30 separable into a front shaft portion and a rear shaft portion so that the ballpoint pen writing body can be replaced.

By the way, a bulging portion 33 is formed at two places on the outer periphery of the shaft cylinder 30 slightly rearward, and a locking portion composed of a convex portion 33b and a concave portion 33a is formed on the front surface of the bulging portion 33. I have. As shown in FIGS. 1 and 2, a tubular portion 31 is extended behind the bulging portion 33, and a circumferential projection 32 a is formed on the peripheral surface of the tubular portion 31. The contact rib 32b is formed in the front part. A guide groove 33c is formed in the inner peripheral portion of the shaft cylinder 30. A partition ring 43 having holes 43a and 43b is fixed in contact with the step portion 42 behind the distal end of the barrel 30.

As described above, the ballpoint pen writing body 1 is placed in the barrel 30 with the return springs 44a, 44b mounted on the outer periphery of the front shaft portion 3 of each ballpoint pen writing body.
a and 1b are inserted and the respective guide grooves 33c are inserted.
The guide ribs 5a and 5b formed on the rear outer peripheral portions of the ballpoint pen writing bodies 1a and 1b are fitted into the front end portions, and the front shaft portion 3 protrudes from the holes 43a and 43b of the partition ring 32b. The ballpoint pen writing bodies 1a and 1b are constantly urged rearward by a return spring provided between the front end of the ink storage unit 4 and the partition ring 32b.

As shown in FIG. 3, the operating body 34 is a cylindrical body having a closed rear end, and a clip 38 connected to a rear outer peripheral portion of the cylindrical body by a base 38a extends forward. or,
The convex portion 41a and the concave portion 41 are provided on the rear surface of the ball portion 41 of the clip 38.
b is formed, and an operating body 3 to be described later is formed.
The convex portion 41 a of the ball portion 41 is disengaged from the concave portion 33 a of the bulging portion 33 due to the circumferential movement of the clip accompanying the rotation of 4.
A circumferential concave groove 39 is formed on the inner periphery of the front end of the operation body 34, and a cam slope 35 is formed on the inner periphery on the rear side thereof, and a notch 36 is formed on the front end thereof.
Are formed. A semicircular groove 40 is formed at the front of the concave groove 39 as shown in FIG.

As described above, the operating body 34 is fitted in the cylindrical portion 31 of the shaft cylinder, the projection 32a is engaged with the concave groove 39 by elastic deformation, and the operating body 34 is rotatable with respect to the shaft cylinder 30 and is prevented from falling off.
In addition, the contact rib 32b of the cylindrical portion 31 is located in the groove 40, and the operating body 34 rotates in a range of approximately 180 degrees with respect to the shaft cylinder 30. At this time, the sliding projections 6a and 6b are in sliding contact with the cam slope 35, and the ballpoint pen writing bodies 1a and 1b alternately move back and forth by the rotation of the operating body 34 with respect to the barrel 30.
When the respective writing tips protrude from the tip end of the barrel, the sliding projections 6a and 6b engage with the notch 36 at the front end of the cam slope 35. Further, when the writing pen of the ball-point pen appears and disappears, the ink storage section 4 is not deformed as described above, but the front shaft section 3 is bent and can be operated smoothly.

In addition to the ballpoint pen writing body described in the above embodiment, the ballpoint pen writing body includes an ink guiding core and an ink absorbing body, and an ink storage mechanism called a collector is provided between the tip and the liquid ink. And the like. In addition, problems such as evaporation of the ink and drying of the writing tip can be realized by devising the ink composition, the tip structure, and the air replacement structure. By the way, the ballpoint pen cursive referred to in claim 1 includes the pen.

[0023]

When the operating body is rotated in one direction with respect to the barrel 30, the sliding projections 6a and 6b of the ballpoint pen writing body are moved to the operating body 3.
With the rotation of 4, the ball-point pen writing body slides along the spiral groove 42, and one of the ball-point pen writing bodies moves forward, and the other retreats, so that the writing tip on the advance side protrudes from the tip opening of the barrel 30. It becomes possible. Further, even if the ink storage portion of the writing pen of the ballpoint pen is not deformed, the writing tip portion flexibly shifts, so that the writing tip portion smoothly comes out of the tip opening without disturbing the operation.

When the ballpoint pen writing body 1a is in a protruding state, as shown in FIG. 1, the ball portion of the clip and the bulging portion of the peripheral surface of the barrel are engaged with each other, and the clip is moved to the breast pocket. And so on.

Next, when the operating body 34 is rotated to the other side, the ball-point pen writing body 1a is retracted, and the writing tip thereof becomes the barrel 30.
And the ballpoint pen writing body 1b moves forward.
At that time, the writing tip is brought into a portable state in which it is accommodated in the barrel 30, and the clip for that state is at a position where the engagement with the bulging portion is released, so that the clip can be easily inserted into a breast pocket or the like. .

When the cap 30 is further rotated, the ball-point pen writing body 1a further retreats, the ball-point pen writing body 1b further advances, and its writing tip projects from the tip opening of the barrel 30. In this state, the clip and the bulge of the peripheral surface of the shaft cylinder are engaged with each other so that the clip cannot be inserted into a breast pocket or the like.

The writing pen 1a for the ballpoint pen is provided with a tip 11
When the ball valve 16 faces upward, the ball valve 16 is positioned on the ball receiving seat 8 of the valve chamber 7 and seals the guide hole 9.
Even if the ink is written upward and the ink on the back surface of the tip ball 12 of the chip runs out, the ink is caught by the head and does not flow backward. Therefore, when the chip 11 is turned downward, the ink can immediately flow out, and the writing is prevented from being rubbed.
(By the way, in the structure without a ball valve, the ink acts in the backward direction when writing upwards, so that air is trapped in the chip and the ink does not follow immediately when writing downwards, causing scuffing.)

In the writing state in which the tip 11 is directed downward, the ball valve 16 abuts on one of the rear ends of the tip 11 in a biased state, and the other side has a flow path through which ink can flow into the tip 11. The ink 18 that has entered the valve chamber 7 from the ink storage tubes 17a and 17b through the conductive holes 9
Is guided to the back of In this state, the tip ball 12 is brought into close contact with the inner edge of the chip holding portion by the pressing of the rod shaft portion 15, so that the direct current of the ink is prevented. In addition, the tip ball 12 slightly retreats due to the writing pressure, so that a gap is created and ink can flow out. By writing, the rotation of the tip ball 12 allows the ink to flow smoothly, and there is no dent and writing with high handwriting density is possible. Becomes On the back surface of the tip ball 12, there is a channel (a seat for the tip ball having a plurality of ink inflow grooves penetrating toward the inner hole of the chip), and the rod shaft portion 15 passes through the center hole of the channel. The ink in the chip is guided to the back of the tip ball 12 through the ink inflow groove and the gap between the center hole and the rod shaft portion 15.

[0029]

The composition and operation of the double-type writing instrument of the present invention are as described above. The dry end of the writing tip is maintained, the seal cap can be removed and the writing tip can be left, and direct current and reverse flow of ink can be prevented. Medium viscosity aqueous with a mechanism to enable
Constructs a low-viscosity oil-based ballpoint pen, with multiple large, non-deformable ballpoint pen-cursives, allowing the writing tip to smoothly appear and disappear. Since it cannot be inserted into a breast pocket, the protruding state of the writing tip can be easily recognized, preventing damage to the human body and clothing due to the sharp edge of the writing tip, and without having to worry about soiling the clothes, etc. Cursive and
Since it is composed of simple components of the operating body and the shaft cylinder, it can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view showing the entirety of a double-type writing instrument according to an embodiment of the present invention, which is partially not shown. In addition, two kinds of ballpoint pen cursives are mounted.

FIG. 2 is an external view of a main part showing a rear part of a shaft cylinder part.

FIG. 3 is a cross-sectional view of the operation body.

FIG. 4 is a sectional view taken along the line AA in FIG. 1;

FIG. 5 is a longitudinal sectional view of a writing pen of a ballpoint pen used in the present invention.

FIG. 6 is a sectional view taken along line BB in FIG. 1;

[Explanation of symbols]

 1a Ball-point pen writing body 1b Ball-point writing body 2 Cylindrical body 3 Front shaft part 4 Ink storage part 5a Guide rib 5b Guide rib 6a Sliding protrusion 6b Sliding protrusion 7 Valve chamber 8 Ball receiving seat 9 Guide hole 10 Inner hole 11 Chip 12 Tip ball 13 Shaft portion 14 Spring 15 Bar shaft portion 16 Ball valve 17 Ink 18 Follower 19 Follower rod 30 Shaft tube 31 Tube portion 32a Projection 32b Contact rib 33 Swelling portion 33a Depression 33b Convex portion 34 Operating body 35 Cam slope 36 Notch 37 Rear end 38 Clip 38a Base 39 Depressed groove 40 Groove 40a Contact part 40b Contact part 41a Convex part 41b Concave part 42 Step part 43 Partition ring 43a Hole 43b Hole 44a Return spring 44b Return spring

Claims (5)

[Claims] 1. A double-type writing instrument in which a plurality of ballpoint pen writing bodies are mounted in a barrel, and each of the writing tips can be alternately protruded and retracted from a tip end of the barrel. An operating body fixed so as to be rotatable only, and a sliding projection integrally provided at a substantially rear end of the ink storage of the ballpoint pen writing body with a cam slope provided on an inner periphery of the operating body, and a shaft. The ballpoint pen writing body is provided so that it can move only in the axial direction with respect to the cylinder, and each ballpoint pen writing body can be moved back and forth by rotating the operating body with respect to the shaft cylinder, and ink storage of the ballpoint pen writing body The portion is substantially non-deformable, and is inserted into the shaft without swinging. A long front shaft portion that can be flexibly bent is provided between the front end of the ink storage portion and the writing tip, and a shaft cylinder is provided. There is a partition behind the front end opening with a hole through which the front shaft portion protrudes. And a return spring for biasing each of the ballpoint pen writing bodies to the rear between the partition and the front end of the ink storage section. 2. An operating body having a notch formed at a front end of a cam slope, a slide protrusion having a cam slope slidingly contacting the cam slope and a rear end engaging with the notch, and a guide rib. 2. The dual writing implement according to claim 1, comprising a ballpoint pen writing body and a shaft cylinder having a guide groove formed in an inner peripheral portion thereof for inserting said guide rib. 3. A clip having a base fixed to one side surface of the operation body and disposed toward the front of the barrel, and a ball provided with a locking portion at a forward end of the clip is provided. A bulging portion provided with a locking portion is provided at a predetermined position on the peripheral surface of the barrel that is in contact with the clip, and only when the operating body is rotated so that the writing tip protrudes from the tip end of the barrel, the clip is removed. 2. The dual writing implement according to claim 1, wherein the ball portion and the engaging portion of the bulging portion are engaged with each other so that the ball portion of the clip does not separate from the shaft cylinder surface. 4. The ballpoint pen writing body has a spring provided so that the tip ball always presses and contacts the inner edge of the ball holding portion at the tip of the tip, and the contact state is released during writing. A water-based ball-point pen ink or a low-viscosity oil-based ink having a so-called shear-thinning property is filled into the ink storage portion, the viscosity of which is reduced due to the rotation of the tip ball accompanying the writing, and a low-viscosity oil-based ink. 2. The dual writing implement according to claim 1, wherein the writing implement is filled with a follower made of a grease-like translucent non-drying substance which moves following the consumption of the writing instrument. 5. The ballpoint pen writing body is provided with a valve chamber in which a ball valve is loosely fitted, facing the rear end of the chip, and the ball valve is in close contact with the rear of the valve chamber to prevent a backflow of ink. 5. The dual writing implement according to claim 4, further comprising a guide hole extending from the ball receiving seat to the ink storage section.