JPH0952487A - Writing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a writing tool wherein looseness of a core lead for writing and a tip member through which the core lead passes is prevented. SOLUTION: A writing tool comprises a core lead 11 for writing, a pen barrel 12 in which the writing core lead 11 is to be inserted, and a tip member 13 which is mounted on the tip of the pen barrel 12 and has a through hole 13a through which the tip of the writing core lead 11 is passed so as to protrude to the outside. In the inside of the tip member 13, a fixing member 14 is provided. The fixing member 14 is pinched by the tip member 13 and the pen barrel 12 so as to be changed elastically toward the inside in the diametric direction by the tip member 13 and to be attached with pressure to the core lead 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a writing instrument, and more particularly to a writing instrument having a construction in which a writing core is mounted in a hollow writing shaft.

[0002]

2. Description of the Related Art Conventionally, as a writing instrument, a writing instrument having a structure in which a writing core is mounted in a hollow writing shaft is known. This type of writing instrument mainly has a configuration shown in FIG. Has been made.

More specifically, the writing instrument indicated by reference numeral 1 in FIG. 11 is a so-called ballpoint pen in which ink or the like is attached to the writing surface by the rotation of a ball, and includes a writing core 2 and this core 2. Hollow brush shaft 3 into which is inserted
And a rear cap 4 screwed to the rear end of the brush shaft 3.
And a tip member 5 screwed to the tip of the pen 3.

The core 2 includes an ink storage tube 6 filled with ink, and a tip 8 mounted on the tip of the ink storage tube 6 and having an ink lead-out ball 7 rotatably mounted thereon. The ink storage tube 6 is mainly made of synthetic resin, and the tip 8 is made of metal or synthetic resin.

A rear end portion of the ink storage tube 6 is fitted into the rear cap 4 to form a core holding hole 4a for fixing the core 2 therein. The member 5 is formed in a tapered funnel shape, and the tip portion of the member 5 is penetrated by the tip 8 of the core 2 held in the brush shaft 3. A through hole 5a that is projected to the outside is formed.

[0006] Such a writing instrument 1 has a great economical advantage because it can be reused by replacing the used core 2 when the ink filled in the core 2 is used up. Further, it is applied not only to oil-based inks but also to water-soluble inks and shearing-thinning inks obtained by improving the water-soluble inks, and to writing instruments using a wide variety of inks.

On the other hand, in such a writing instrument 1, the axial component of the writing pressure at the time of writing is supported by the rear cap 4 via the tip 8 and the ink storage tube 7, and is also orthogonal to the axial line. But the chip 8 and the through hole 5a
It is supported by the tip member 5 by abutting against the inner wall thereof, and writing is performed.

[0008]

By the way, in the conventional writing instrument 1 as described above, the following problems to be improved remain.

That is, in the writing instrument 1, a through hole 5a is formed in the tip portion of the tip member 5, and the tip of the tip 8 of the core 2 is exposed to the outside of the tip member 5 through the through hole 5a. Although it is made to project, the inner diameter of the through hole 5a is set to the inner diameter of the chip 8 in order to ensure the insertion of the chip 8 in consideration of variations in the dimensions of the through hole 5a and the chip 8 during manufacturing. The diameter is slightly larger than the outer diameter, and due to this, the inner surface of the through hole 5a and the chip 8 are
As shown in FIG. 11, a gap g is formed between the outer surface of the chip 8 and the outer surface of the chip, and the existence of the gap g causes the chip 8 to rattle.

Then, in this way, the tip 8 has the tip member 5
When it wobbles inside, when writing or carrying, the tip 8 collides with the inner wall of the through hole 5a, which causes abnormal noise, or the wobble of the tip 8 during writing disturbs the handwriting. Occurs.

The present invention has been made in view of the above-mentioned conventional problems, and provides a writing instrument in which rattling between a writing core and a tip member through which the core penetrates is prevented. With the goal.

[0012]

In order to achieve the above-mentioned object, a writing instrument according to a first aspect of the present invention comprises a writing core and a writing shaft into which the writing core is inserted. A tip member that is attached to the tip of the writing shaft and has a through hole through which the tip of the writing core is made to penetrate and is projected to the outside. By being sandwiched between the tip member and the brush shaft, the tip member is elastically deformed inward in the radial direction,
It is characterized in that a fixing member which is brought into pressure contact with the core is provided.

According to a second aspect of the present invention, in the writing instrument according to the first aspect, a conical space is formed in the tip member, which is continuous with the through hole and gradually increases in diameter toward the rear of the tip member. The fixed member is arranged in the large diameter portion of the space of the tip member so as to be movable in the axial direction thereof,
An annular base portion that is brought into contact with the tip of the brush shaft, and a base member that extends from this base portion toward the through hole of the tip member and is elastically deformed along the inner surface of the tip member, It is characterized in that it is formed by a sandwiching section that is press-fitted between the core and the core.

According to a third aspect of the present invention, in the writing instrument according to the second aspect, a tip end portion of the holding portion is an inner surface of a through hole of the tip member and a writing core to be fitted into the through hole. Is projected to the outside from the gap, and an engaging step portion which is engaged with the outer surface of the tip end portion of the tip member is formed on the outer peripheral portion of the projected portion.

A writing instrument according to a fourth aspect of the present invention is characterized in that the sandwiching portion according to the second or third aspect is divided into a plurality along the circumferential direction.

Further, the writing instrument according to claim 5 of the present invention is the writing instrument according to any one of claims 1 to 4, wherein the contact portion of the fixing member with the writing shaft is elastically deformable in the length direction of the writing shaft. It is characterized in that a stretchable portion is formed.

[0017]

According to the writing instrument of the first aspect of the present invention, after the core is mounted in the brush shaft, the tip member is aligned with the tip of the brush shaft, and then the tip member is formed. The tip member is assembled along the axial direction of the brush shaft while inserting the core into the through hole.

When the tip member is attached to the brush shaft, the fixing member mounted in the tip member is sandwiched between the tip member and the brush shaft, so that the inner surface of the tip member causes The member is elastically deformed toward the central portion of the member, and is pressed against a core located in the central portion.

As a result, the tip member and the core are integrated with each other via the fixing member, and the rattling of the core is prevented.

According to the writing instrument of the second aspect of the present invention, by mounting the tip member on the tip portion of the brush shaft, the fixing member is moved together with the tip member toward the tip surface of the brush shaft.

Then, by further relative movement of the tip member and the brush shaft, the base portion of the fixing member is brought into contact with the tip of the writing shaft, and after the movement of the fixing member is stopped, the inner surface of the tip member is The sandwiched portion abutted on the elastic member is elastically deformed toward the central portion of the tip member by the inner surface of the tip member which is formed in a tapered conical shape.

As a result, the core is clamped and fixed in the circumferential direction by the clamping section, and the core and the tip member are fixed uniformly in the circumferential direction.

According to the writing instrument of the third aspect of the present invention, the tip portion of the holding portion of the fixing member is projected to the outside from the through hole of the tip member, and the protruding portion has the above-mentioned structure. Since the engagement step portion that engages with the tip end surface of the tip member is provided, the tip of the fixing member is engaged by the engagement of the engagement step portion and the tip member when the tip member is removed from the brush shaft. Detachment from the member is prevented.

As a result, even when the tip member is removed from the brush shaft, for example, when replacing the core, the tip member and the fixing member are handled integrally, and the fixing member is prevented from being lost, and The reattachment operation is simplified.

According to the writing instrument of the fourth aspect of the present invention, since the holding portion of the fixing member is divided into a plurality of portions in the circumferential direction, the deformation toward the center of the holding portion is facilitated. By this, the core is fixed more securely by the sandwiching portion.

Further, according to the writing instrument of the fifth aspect of the present invention, when the fixing member is sandwiched between the tip member and the brush shaft, there are variations in the dimensions of the fixing member and the tip member. Even in this case, the expansion and contraction portion provided on the fixing member is elastically deformed to absorb the above-mentioned dimensional variation.

Therefore, by making the axial length of the fixing member slightly larger than the design value, the contact between the fixing member and the core is surely obtained, and at the same time, the tip member and the brush shaft are connected. The fitting position is fixed.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 3 and FIGS. In addition,
In the following description, the same parts as those of the conventional example shown in FIG.

In FIG. 1, reference numeral 10 indicates a writing instrument according to the present embodiment. The writing instrument 10 is a writing core 11.
The writing shaft 12 into which the writing core 11 is inserted, and the writing shaft 12 are attached to the tip end of the writing shaft 12. The tip end of the writing core 11 is penetrated and protruded to the outside. A tip member 13 having a through hole 13a (see FIGS. 5 and 6) is provided, and by being sandwiched between the tip member 13 and the brush shaft 12, inside the tip member 13,
The fixing member 14 is elastically deformed inward in the radial direction by the tip member 13 and is provided with a fixing member 14 that is brought into pressure contact with the core 11.

Next, these details will be explained.
The core 11 is composed of an ink storage tube 6 and a tip 8 which is connected to the tip of the ink storage tube 6 and is provided with a ball 7 for drawing out ink.
The brush shaft 12 is inserted into the brush shaft 12 and
By being fitted in the rear cap 4 screwed to the rear end, the brush shaft 12 is temporarily held in the axially positioned state.

The tip member 13 is formed in a substantially funnel shape having a small diameter at its tip, and is screwed to the tip of the brush shaft 12 via a screw 15 at the large diameter portion at the rear portion thereof. The fixing member 14 is mounted inside so as to be movable in the axial direction.

The fixing member 14 is formed of an elastic material such as synthetic resin, and in this embodiment, as shown in FIG. 1, an annular shape having an outer diameter larger than the inner diameter of the through hole 13a of the tip member 13. 14a of FIG. 1 and FIGS.
As shown in FIG. 3, the base portion 14a is configured by a sandwiching portion 14b protruding from one end of the base portion 14a along the axial direction, and the sandwiching portion 14b, as shown in FIG. It is provided at four locations with intervals.

Further, engaging projections 14c projecting outward in the direction perpendicular to the axis are provided at the tips of the sandwiching portions 14b.
Is integrally formed, and the surface of the engaging projection 14c on the side of the base portion 14a is, as shown in FIG.
3 is an engaging stepped portion 14d that is engaged with the tip end surface of No. 3.

Further, in this embodiment, the base 1
A portion of 4a that is opposed to the tip end surface of the brush shaft 12 is formed in a tapered shape so as to become thinner toward the brush shaft 12, and an elastically deformable expandable portion 14 is provided.
It is said to be e.

In the fixing member 14, the tip member 13 is screwed to the brush shaft 12 to a predetermined position, and the holding portions 14b are applied to the core 11 by the tip member 13 at a predetermined pressure. In such a state that the end portion of the base portion 14a facing the brush shaft 12 is located at a position where it can be brought into pressure contact with the brush shaft 12 so that the end portion of the base portion 14a is located behind the brush shaft 12 by a predetermined length. The overlapped dimensions are absorbed by elastic deformation of the stretchable portion 14e of the base portion 14a.

Next, a method for assembling the writing instrument 10 of the present embodiment having the above-described structure will be described.

First, the rear cap 4 is attached to the rear end of the brush shaft 12.
Attach the core 11, from the tip opening of this brush shaft 12,
The core 11 is temporarily fixed to the brush shaft 12 by inserting from the rear side and fitting the rear end of the core 11 into the core holding hole 4a of the rear cap 4.

Further, the fixing member 14 is inserted from the holding portion 14b side through the rear opening of the front member 13, and each holding portion 14 is inserted.
The engaging projection 14c provided at the tip of b is projected from the through hole 13a of the tip member 13 to the front of the tip member 13.

When the fixing member 14 is mounted as described above, the holding portions 14b are provided with engaging projections 14c at their tips.
By being slid on the inner surface of the tip member 13, it is tilted radially inward by this inner surface, and when the engaging projection 14c is projected outward of the tip member 13, It is deformed outward in the radial direction by its own elastic force.

At this time, the outer peripheral surface of each holding portion 14b has a through hole 13 in the tip member 13 due to the elastic force of each holding portion 14b.
It is brought into contact with the inner surface of a and the engaging stepped portion 14d of each sandwiching portion 14b is opposed to the tip end surface of the tip member 13, and the fixing member 14 is separated from the tip member 13. When it is moved in the direction
4d and the tip end surface of the tip member 13 are brought into contact with each other, so that the detachment thereof is prevented.

Then, the tip member 13 to which the fixing member 14 is attached in this way is replaced with the brush shaft 12 to which the core 11 is attached.
By aligning with the tip of the brush shaft 12 and inserting the core 11 protruding from the tip of the brush shaft 12 into the fixing member 14 and screwing the tip member 13 to the brush shaft 12 via the screw 15. As shown in FIG. 1, the writing instrument 10 of this embodiment is assembled.

When the tip member 13 is screwed onto the brush shaft 12, the base portion 14a of the fixing member 14 is separated from the tip surface of the brush shaft 12 in the initial stage as shown in FIG. With the progress of screwing of the tip member 13, the fixing member 14 together with the tip member 13 is fixed to the brush shaft 1.
2 is moved toward the tip end surface of the fixing member 14, but at this time point, the sandwiching portions 14b of the fixing member 14 have the leading member 13
Since the inner surface of the through hole 13a is brought into contact with the holding portions 14b so that the space between the holding portions 14b is largely opened, the tip end portion of the core 11 inserted into the fixing member 14 has the above-mentioned holding portions. It passes through between 14b and is made to project outside from the tip of the tip member 13.

When the screwing of the tip member 13 is advanced from such a state, the base portion 14a of the fixing member 14 which is moved together with the tip member is brought into contact with the tip surface of the brush shaft, so that the fixing member is fixed. Although the movement of the front member 14 is stopped, the front member 13 is relatively moved toward the base portion 14 a of the fixed member 14 by the further screwing of the front member 13.

Since the inner diameter of the through hole 13a of the tip member 13 is smaller than the outer diameter of the base portion 14a of the fixing member 14, the relative distance between the tip member 13 and the fixing member 14 described above is large. Due to the movement, the inner surface of the through hole 13a of the tip member 13 causes each of the sandwiching portions 14b to be tilted so that the tip end portion thereof is directed inward in the radial direction. It is pressed against the outer surface.

As a result, as shown in FIG. 6, the center core 11 is fixed to the tip member 13 by being held by the plurality of holding portions 14b. Therefore, rattling between the core 11 and the tip member 13 is eliminated, generation of abnormal noise due to a collision between the core 11 and the tip member 13 during transportation or writing, and wobble during writing. Is eliminated and disorder of handwriting is prevented.

Since the tilting amount of the holding portion 14b tilted by the tip member 13 is continuously changed in proportion to the relative movement amount of the tip member 13 and the fixing member 14 in the axial direction, Even if there are variations in the dimensions of the core 11 (chip 8), the tip member 13, or the fixing member 14, these variations are absorbed and the core 11 is reliably sandwiched and fixed.

Moreover, in this embodiment, since the core 11 is clamped by the four clamping portions 14b, the clamping force on the core 11 acts uniformly on the peripheral surface of the core 11. From this point as well, the fixing of the core 11 is surely and stably performed.

Further, in the present embodiment, each holding portion 14
engaging projection 14c and tip member 13 provided at the tip of b
The front member 1 of the fixing member 14 is engaged with the tip surface of the
Since the detachment from 3 is prevented, the fixing member 14 will not be lost even if the tip member 13 is removed from the brush shaft 12 when the core 11 is replaced, and Is handled integrally, the attaching / detaching operation of the tip member 13 can be easily performed.

On the other hand, the fixing member 14 is replaced with the front member 1.
3 is screwed to the brush shaft 12 to a predetermined position, and the holding portions 14b are positioned at positions where the holding members 14b are brought into pressure contact with the core 11 by the tip member 13 with a predetermined pressure. The end of 14a facing the brush shaft 12 is set to have a size such that the end of the brush shaft 12 is located behind the brush shaft 12 to the rear side of the brush shaft 12 by a predetermined length. A portion of the brush shaft 12 facing the tip end surface is elastically deformable in a tapered shape so that the thickness becomes thinner toward the brush shaft 12.
By setting e, the overlapped dimension is
As shown in FIG. 4, even if the elastic member 14e of the base portion 14a is elastically deformed and the tip member 13 and the fixing member 14 have dimensional variations, the variation is absorbed by the elastic deformation of the elastic portion 14e. .

As a result, the tip member 13 and the brush shaft 12 are securely screwed to a predetermined position without causing a gap therebetween, and excessive clamping pressure by the clamping portions 14b. The action is prevented, and the holding force of the core 11 is appropriately held.

The shapes, sizes, etc. of the respective constituent members shown in the above embodiment are merely examples, and can be variously changed based on design requirements and the like.

For example, the fixing member 1 in the above embodiment.
Although an example in which the base portion 14a constituting 4 is a continuous annular body is shown, as shown in FIG. 4, a fixing member 16 having a base portion 16a in which a discontinuous portion S is partially formed can be used. is there. With such a configuration, the base portion 1
6a itself is also given an elastic deformation function in the radial direction, and the degree of freedom of posture change at the time of tilting of the sandwiching portion 16b continuously provided to the base portion 16a is increased, and when sandwiching the core 11, Familiarity between the sandwiching portions 16b and the core 11 is improved.

Further, the fixing member 14 is provided with a dividing groove along the radial direction.
Although the example in which the number of the sandwiching portions 14b is four by forming them at intervals of 90 degrees in the circumferential direction is shown, the interval of the dividing grooves is 120 degrees as shown in FIG. The fixing member 17 having the sandwiching portion 17b may be provided, and the number thereof can be set arbitrarily.
As shown in (b), it is also possible to use a fixing member 18 having one holding portion 18b.

Further, like the fixing member indicated by reference numeral 19 in FIGS. 9 and 10, the sandwiching portion 1 which is continuously provided on the base portion 19a.
9b may be a continuous annular body, and the engaging projection 19c and the engaging stepped portion 19d may be formed at the tip of the holding portion 19b.

In this case, the nipping portion 19b is elastically deformed by the tip member 13 in the diameter reducing direction, so that the nipping portion 19b is pressed into contact with the outer periphery of the core 11, and the core 11 is clamped.

[0056]

As described above, according to the first aspect of the present invention.
According to the writing instrument of the present invention, by mounting the tip member on the writing shaft, the fixing member mounted in the tip member is
The tip member is sandwiched between the tip member and the brush shaft, and is elastically deformed toward the center of the tip member by the inner surface of the tip member, so that the tip core is pressed into contact with the center core arranged in the center portion, whereby the tip member The core and the core can be integrated via the fixing member. As a result, it is possible to prevent rattling of the core with respect to the tip member, prevent generation of abnormal noise due to this rattling, and prevent disorder of handwriting due to wobbling of the core. it can.

According to the writing instrument of the second aspect of the present invention, by mounting the tip member on the brush shaft, the base of the fixing member is brought into contact with the tip of the brush shaft to stop the movement of the fixing member. After that, the sandwiching portion continuously provided to the base portion is elastically deformed toward the center portion by the tapered inner surface of the tip member, and to the narrow portion formed by the tip inner surface of the tip member and the core. Can be pressed.

Thus, by sandwiching and fixing the core in the circumferential direction by the sandwiching section, the core can be uniformly fixed in the circumferential direction, and stable fixing can be performed.

Further, according to the writing instrument of the third aspect of the present invention, the tip end portion of the sandwiching portion of the fixing member is projected outward from the through hole of the tip member, and the tip end surface of the tip member is provided at the projecting portion. By providing the engagement step portion that engages with the front member, the engagement of the engagement step portion and the tip member prevents the fixing member from being separated from the tip member when the tip member is removed from the brush shaft. be able to.

Thus, for example, when replacing the core, even if the tip member is removed from the brush shaft, the tip member and the fixing member can be integrally handled, and the fixing member can be prevented from being lost. In addition, the tip member can be easily attached and detached.

Further, according to the writing instrument of the fourth aspect of the present invention, by dividing the holding portion into a plurality of portions in the circumferential direction,
It is possible to facilitate elastic deformation of the holding portion toward the center core, and to fix the center core smoothly and reliably.

Further, according to the writing instrument of the fifth aspect of the present invention, an expanding / contracting portion which is elastically deformable in the length direction of the writing shaft is formed at the contact portion of the fixing member with the writing shaft. By this, even when there is a dimensional variation in the tip member or the fixed member, the variation can be absorbed by the elastic deformation of the expansion / contraction portion, and the required accuracy of the component is moderated,
The yield can be improved.

By making the length of the fixing member slightly longer than the design value, the elastic deformation of the expansion / contraction portion allows the movement of the leading member, and the clamping force of the core by the clamping portion. It is possible to securely screw the tip member and the brush shaft to a predetermined position while ensuring the above, and it is possible to prevent excessive pinching of the core by the pinching portion.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is an enlarged side view of a fixing member used in an embodiment of the present invention.

FIG. 3 is an enlarged front view of a fixing member used in an embodiment of the present invention.

FIG. 4 shows another embodiment of the present invention and is an enlarged front view of a fixing member.

FIG. 5 is an explanatory view of the operation of the embodiment of the present invention, which is a vertical cross-sectional view of a main part showing an initial state when the tip member is attached to the brush shaft.

FIG. 6 is an explanatory view of the operation of the embodiment of the present invention, which is a vertical cross-sectional view of a main part showing a state in which the tip member is attached to the brush shaft.

FIG. 7 shows another embodiment of the present invention and is a vertical cross-sectional view of a main part showing a state in which the tip member is attached to the brush shaft.

FIG. 8 shows another embodiment of the present invention and is an enlarged front view of a fixing member.

FIG. 9 shows still another embodiment of the present invention and is an enlarged side view of a fixing member.

FIG. 10 shows another embodiment of the present invention and is an enlarged front view of a fixing member.

FIG. 11 is a vertical sectional view showing a conventional example.

[Explanation of symbols]

 10 Writing Tool 11 Center Core 12 Brush Axis 13 Tip Member 14, 16, 17, 18, 19 Fixing Member 14a, 16a, 17a, 18a, 19a Base 14b, 16b, 17b, 18b, 19b Clamping Part 14c, 19c Engagement Protrusion 14d・ 19d Engaging step portion 14e Expansion / contraction portion

Claims (5)

[Claims] 1. A writing core, a writing shaft into which the writing core is inserted, a writing shaft mounted at the tip of the writing shaft, and a tip of the writing core penetrating therethrough. And a tip member formed with a through hole that is projected outwardly. The tip member is sandwiched between the tip member and the brush shaft so that the tip member is directed radially inward. A writing instrument comprising a fixing member which is elastically deformed and is brought into pressure contact with the core. 2. The conical space, which is continuous with the through hole and gradually increases in diameter toward the rear of the front member, is formed in the front member, and the fixing member has a large space of the front member. An annular base portion is provided in the diameter portion so as to be movable in the axial direction thereof and is brought into contact with the tip of the brush shaft, and the base portion is extended from the base portion toward the through hole of the tip member. By being elastically deformed along the inner surface of the member,
The writing instrument according to claim 1, wherein the writing instrument is formed by a sandwiching section that is press-fitted between the tip member and the core. 3. A tip portion of the sandwiching portion is projected outward from a gap between an inner surface of a through hole of the tip member and a writing core fitted in the through hole, and the projection thereof. The writing instrument according to claim 2, wherein an engaging step portion that is engaged with the outer surface of the tip end portion of the tip member is formed on the outer peripheral portion of the portion. 4. The writing instrument according to claim 2, wherein the holding portion is divided into a plurality of pieces along the circumferential direction. 5. A contact portion of the fixing member with the brush shaft,
The writing instrument according to any one of claims 1 to 4, wherein an elastically deformable expandable portion is formed in a length direction of the writing shaft.