JPH10315685A - Cap of writing instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cap of writing instruments that can be sealed with an inner cap in its air replacement holes formed near the pen tip part of writing instruments and the pen tip part in the stem of the writing instruments, and prevent the compression and decompression of air within the cap at the time of removing the cap, and also can reduce the number of parts to be incorporated in the inner cap for lowering costs. SOLUTION: This cap comprises a bottomed seal sleeve part 20 for covering and sealing a pen tip part 18 of writing instruments 2 and an air replacement holes 14 made near the pen tip 18, and an inner cap 17 is installed in the interior part of a cap mainbody 16, in which a flange 21 is included on the opening end outer periphery of the seal sleeve part 20, its entirety being formed of pliable and elastic material, the flange 21 is put in contact with a cap main body 15, or a contact part 26 with the stem 3 of the writing instrument is set at the position near the central side in the diameter direction closer than the contact position with the cap main body 16 in the flange 21, and when the contact part 26 is pushed by the stem 3 of writing instruments, the seal sleeve part 20 is slidable through its elastic deformation in the pushing direction of the stem 3 of the writing instruments.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a writing instrument cap having an inner cap.

[0002]

2. Description of the Related Art An ink tank for directly storing ink is provided inside a shaft. When the ink in the ink tank is excessively extruded due to expansion or the like due to a rise in temperature, the excess ink is dispensed with a pen. 2. Description of the Related Art A writing instrument having an ink reservoir that absorbs temporarily so as not to blow out from a tip portion or the like is known. As a detachable cap for such a writing instrument, a cap having an inner cap capable of sealing an air replacement hole provided in a pen tip portion and a writing instrument shaft near the pen tip portion is known.

In a cap having such an inner cap, in order for the inner cap to securely seal the tip of the writing implement, it is necessary to lock the writing implement shaft to the cap body after the tip of the writing implement is inserted into the inner cap. There is. Therefore, after the tip of the writing implement is inserted into the inner cap to be in a sealed state, the tip of the writing implement is further pushed into the inner cap, so that the air in the inner cap is compressed and increased in pressure, and the air is compressed. The phenomenon that the ink in the ink tank was pushed out excessively by entering the ink tank inside the writing instrument shaft from the air replacement hole and the pushed ink was stored in the ink reservoir. On the other hand, when the cap is removed from the writing instrument shaft, the inside of the inner cap is depressurized, so that an excessive amount of ink is drawn out of the ink tank, and the ink is stored in the ink reservoir. Therefore, the ink in the ink reservoir continues to increase every time the cap is attached and detached, and when the ink reservoir becomes full of ink, there has been a problem that the overflowed ink leaks from the air replacement hole.

[0004] In order to solve such a problem, the present applicant has previously developed a cap as disclosed in Japanese Utility Model Publication No. Hei 6-17581. This cap is mounted so that it can move in the axial direction while supporting the inner cap with a coil spring.When the inner cap is pressed by the writing instrument shaft, it moves while compressing the coil spring, and the air inside it moves to the writing instrument axis. Is not compressed.

[0005] However, the use of the coil spring increases the number of parts and increases the number of assembly steps.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a pen tip of a writing implement and an air replacement hole provided in the vicinity of the pen tip of the writing implement shaft, which can be sealed with an inner cap. It is possible to provide a writing instrument cap that can prevent the air inside the inner cap from being increased or reduced in pressure at the time, and can further reduce the number of parts to be assembled to the inner cap to reduce cost. Make it an issue.

[0007]

The above object is achieved by the writing instrument cap of the present invention, that is, the pen tip portion 18 of the writing instrument 2 and the air replacement hole 1 provided in the vicinity of the pen tip portion 18.
4 and has a flange 21 on the outer periphery of the open end of the seal cylinder 20 to seal the entirety of the seal cylinder 20. The seal cylinder 20 is entirely formed of a flexible and elastic material. The flange 21 is in contact with the cap body 16, and the writing implement shaft 3 is located at a position closer to the center in the radial direction than the contact point of the flange 21 with the cap body 16.
When the abutment portion 26 is set and the abutment portion 26 is pressed by the writing implement shaft 3, the inner cap 17 that can be moved in the pushing direction of the writing implement shaft 3 by the elastic cylindrical deformation of the seal tubular portion 20 is elastically deformed. The problem can be solved by a writing instrument cap that is provided inside the cap body 16.

At the same time, in order to absorb dimensional errors in the writing instrument shaft 3 and / or the cap body 16 in the axial direction,
In addition to the above configuration, it is desirable to provide elastic projections 22 and 28 at the contact points between the flange 21 of the inner cap 17 and the cap body 16 when the inner cap 17 is pressed by the writing implement shaft 3. This elastic projection can be provided on the inner cap side or on the cap body side. Further, the elastic projections can be provided separately at a plurality of positions on the circumference, or can be provided so as to have an annular shape. In addition,
It is desirable that the elastic projections 22 and 28 be shaped so as to be easily deformed, that is, so that the reaction force against the writing instrument shaft 3 is weak and the cap does not easily come off the writing instrument.

Further, in order to facilitate the assembly of the inner cap 17 to the cap body 16, in addition to the above-described configuration, a locking flange 30 for the cap body 16 is provided with a seal cylinder portion 20 of the inner cap 17.
It is preferable to protrude from the outer peripheral portion.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. First, FIGS. 1 to 4 relate to the first embodiment.
FIG. 1 shows a state before the cap 1 is fitted to the writing implement 2. The writing implement 2 forms a writing implement shaft 3 by joining a front shaft 5 to a front end (an upper side of the drawing is a front side) of a shaft main body 4, and an ink tank that stores ink directly in the rear half of the writing implement shaft 3 ( The illustration is omitted), and an ink reservoir 6 is disposed in front of the ink tank. The ink storage body 6 has a number of blades 7 on the outer peripheral portion, and an ink storage groove 8 is formed between the blades 7. Each ink storage groove 8 communicates with an ink guide groove 9 in the front-rear direction, and the rear end of the ink guide groove 9 communicates with the ink tank. When the ink in the ink tank is excessively pushed out of the ink tank due to expansion due to a rise in temperature, the excess ink is absorbed into the ink storage groove 8 through the ink guide groove 9. The ink reservoir 6 has a front-rear direction through hole 10 at the center, and the ink guide core 1 is inserted into the through hole 10.
1 is inserted. The ink guide core 11 has a rear end portion protruding into the ink tank, and guides the ink in the ink tank forward by absorbing the ink by capillary action. A tip 1 with a pen core 12 attached to the front end of the ink reservoir 6
3 and the front end of the ink guide core 11 is connected to the tip 13 thereof. The ink guided to the front end of the ink guide core 11 is supplied to the pen core 12 of the tip 13 and further sent to the pen tip 18 of the pen core 12 to be able to write. An air replacement hole 14 is opened at the front end position of the tip shaft 5 in the vicinity of the pen tip portion 18, and the air replacement hole 14 is opened to the inside of the writing instrument shaft 3, and a part of the blade 7 of the ink reservoir 6 is opened. It communicates with the ink tank through an air flow passage 15 formed by cutting.

On the other hand, the cap 1 comprises a hard plastic cap body 16 and an inner cap 17 mounted therein. Inner cap 1
Numeral 7 is formed of a material having flexibility and elasticity, for example, rubber or soft plastic, and has a bottomed seal tube portion 20 and a flange 21 protruding from an outer peripheral portion of an opening end thereof as shown in FIG. In addition, frustoconical elastic projections 22 are integrally provided at a plurality of locations on the circumference of the front surface of the flange 21. The inner cap 17 inserts the seal tube portion 20 into the hole 23 at the back of the cap body 16 and inserts the elastic projection 22 of the flange 21 into the hole 23.
Is mounted so as to abut the step 24 around the flange 21, and the flange 21 is hooked by a projection 25 provided on the inner surface of the peripheral wall of the cap body 16.

FIG. 4 shows a state in which the tip of the writing instrument 2 is inserted into the inner cap 17 to seal the pen tip 18 and the air replacement hole 14. When the tip of the writing instrument 2 is inserted into the inner cap 17, the tip of the pen core 12 first comes into contact with the barbed portion 27 provided at the bottom of the seal tube 20, and then the front end corner of the tip shaft 5 of the writing instrument shaft 3. 19 contacts the flange 21 of the inner cap 17 to seal the pen tip 18 and the air replacement hole 14. When the front end corner 19 of the front shaft 5 is brought into contact with the flange 21, the elastic projection 22 provided on the flange 21 is compressed by the pressure. The deformation of the elastic projection 22 absorbs an axial dimensional error of the writing instrument shaft 3 and / or the cap body 16. The location where the front end corner 19 of the tip shaft 5 abuts against the flange 21 of the inner cap 17 is closer to the center in the radial direction than the location where the elastic projection 22 of the flange 21 abuts against the step portion 24 of the cap body 16. It is set closer to and is located substantially on the extension of the seal cylinder 20. That is, the contact portion 26 between the front end corner portion 19 of the tip shaft 5 and the flange 21 of the inner cap 17 is formed by the elastic projection 22 and the step portion 2 of the cap body 16.
4 is offset with respect to the point of contact. As a result, after the elastic projection 22 of the flange 21 is compressed as described above, the inner end of the flange 21 is pressed by the front shaft 5 to bend and deform. Will move to the position. Then, an engagement projection provided near the opening end of the cap body 16 (not shown)
And the engaging projection (not shown) provided on the shaft main body 4 is locked, and the writing implement 2 and the cap 1 are fixed. That is, when the distal end portion of the writing instrument 2 is sealed by the inner cap 17, compression of the air in the inner cap 17 can be avoided by moving the position of the seal tube 20. The compression of the elastic projection 22 of the flange 21 mainly absorbs the dimensional error as described above. However, the compression of the elastic projection 22 also causes the position movement of the seal cylindrical portion 20. Compression is also inner cap 1
The effect of preventing the compression of the air in the chamber 7 is synergistically enhanced.

Next, FIGS. 5 and 6 relate to a second embodiment. The second embodiment differs from the first embodiment in the shape of the elastic projection 28 provided on the flange 21 of the inner cap 17. That is, as shown in FIG.
Is provided with an annular elastic projection 28. When the elastic projection 28 is formed in an annular shape, a rib 29 that contacts the elastic projection 28 may be provided at an appropriate position on the inner surface of the cap body 16 as shown in FIG. There is no trouble in positioning the elastic projection 28. Other structures and functions are the same as those in the first embodiment.

Next, FIGS. 7 to 10 relate to a third embodiment. In the third embodiment, as shown in FIGS. 7 and 8, a hooking flange 30 is provided on the outer periphery of the tip end of the seal tube 20 in the inner cap 17, and the hooking flange 30 is shown in FIG. In this manner, the inner cap 17 is attached by being hooked on the projection 31 provided on the inner surface of the cap body 16. When the inner cap 17 of the first embodiment or the second embodiment is assembled to the cap body 16, the flange 21 is attached to the cap body 1 as described above.
A method is adopted in which the protrusions 25 provided on the inner surface of 6 are deformed so as to get over the protrusions and are fitted into the grooves 32. However, if the flange 21 is soft, it is difficult to fit into the grooves 32. On the other hand, if the hooking flange 30 is provided on the outer peripheral portion of the seal tube portion 20 as in the third embodiment, FIG.
As shown in FIG. 0, the jig 33 is inserted into the seal tube 20 and pushed in, so that the latching flange 30 can be easily brought into the convex portion 31.
, So that the inner cap 17 can be easily attached to the cap body 16. Other structures and functions are the same as those in the first embodiment.

[0015]

The cap of the writing instrument according to the present invention is as described above. When the pen tip 18 of the writing instrument 2 and the air replacement hole 14 are sealed by the inner cap 17, the air in the inner cap 17 is compressed. Can be avoided. Therefore, as described above, the accumulation of the ink in the ink reservoir 6 provided in the writing instrument 2 is suppressed, and the air replacement hole 1 is formed.
4 can be prevented from leaking out. The present invention provides such an effect to the inner cap 17.
Therefore, there is no adverse effect of increasing the number of parts and the number of assembling steps and increasing the cost. Further, by providing the elastic projections 22 and 28 as described in claim 2, there is also obtained an advantage that a dimensional error of the writing instrument shaft 3 and the cap body 16 can be absorbed. Further, by forming the elastic projections 28 in an annular shape as described in claim 3, there is an advantage that the alignment of the elastic projections 28 with respect to the cap body 16 becomes unnecessary. Further, as described in claim 4, by providing the latching flange 30 on the outer peripheral portion of the seal tube portion 20 of the inner cap 17, there is also obtained an advantage that the assembly of the inner cap 17 to the cap body 16 is facilitated. Can be

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state before a cap is fitted to a writing instrument.

FIG. 2 is a perspective view of an inner cap.

FIG. 3 is a partially enlarged cross-sectional view showing a state before the inner cap seals a writing implement tip.

FIG. 4 is a partially enlarged cross-sectional view showing a state after the inner cap has sealed the tip of the writing implement.

FIG. 5 is a perspective view of an inner cap.

FIG. 6 is a sectional view of a cap.

FIG. 7 is a perspective view of an inner cap.

FIG. 8 is a sectional view of the inner cap.

FIG. 9 is a sectional view of a cap.

FIG. 10 is a sectional view showing a state where the inner cap is assembled to the cap body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cap 2 Writing implement 3 Writing implement shaft 4 Shaft main body 5 Tip shaft 6 Ink storing body 7 Blade 8 Ink storing groove 9 Ink guide groove 10 Through hole 11 Ink guide core 12 Pen core 13 Tip 14 Air replacement hole 15 Air flow passage 16 Cap body 17 Inner cap 18 Pen tip part 19 Front end corner of tip shaft 20 Seal cylinder part 21 Flange 22 Elastic projection 23 Hole part 24 Step part 25 Projection 26 Contact part 27 Navel part 28 Elastic projection 29 Rib 30 Hanging flange Part 31 convex part 32 groove 33 jig

Claims (4)

[Claims] 1. A seal cylinder portion (20) having a bottom that seals and covers a pen tip portion (18) of a writing instrument (2) and an air replacement hole (14) provided near the pen tip portion (18). Has a flange 21 on the outer periphery of the open end thereof, and is entirely formed of a material having flexibility and elasticity. The flange 21 is in contact with the cap body 16, and the flange 21 is in contact with the cap body 16. The contact portion 26 with the writing tool shaft 3 is set at a position closer to the center in the radial direction than the location, and when the contact portion 26 is pressed by the writing tool shaft 3, the seal cylinder portion 20 is elastically deformed. A cap for a writing implement, comprising an inner cap (17) movable in a direction in which the writing implement shaft (3) is pushed in the cap body (16). 2. An inner cap 1 is provided at a contact point between the flange 21 of the inner cap 17 and the cap body 16.
2. The writing instrument cap according to claim 1, wherein elastic projections (22, 28) that compress when the writing instrument (7) is pressed by the writing instrument shaft (3) are provided. 3. The elastic projection 28 is formed in an annular shape.
Writing instrument cap as described. 4. A hanging flange 3 for the cap body 16.
The writing instrument cap according to claim 1, wherein the “0” protrudes from an outer peripheral portion of the seal tube portion of the inner cap.