JP4002011B2 - Cap back insertion structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cap back insertion structure in a writing instrument. More specifically, the present invention relates to a cap back insertion structure in which a cap removed from the pen tip side of the writing instrument body is attached to the rear end of the writing instrument body.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a cap back-insertion structure in which a cap opening end outer surface is fitted to a concave inner surface of a writing instrument main body rear end, the cap generally has a tapered shape whose diameter is increased on the opening end side.
[0003]
Therefore, when the cap is inserted into the recess of the writing instrument body, if the cap is inserted even slightly obliquely with respect to the writing instrument body, the outer peripheral edge of the cap opening end contacts the inner peripheral edge of the recess opening end before contacting the inner surface of the recess. Since it tends to come into contact with the portion, smooth insertability is hindered. In addition, when removing the cap from the concave portion of the writing instrument body, the outer shape of the cap is a tapered shape with an enlarged diameter on the cap opening end side (that is, a shape that reduces the diameter in the direction of removing the cap). It is not easy to remove.
[0004]
Japanese Utility Model Publication No. 3-42681 discloses a cap for a writing instrument in which a hook-shaped portion is formed on the head end to form a recessed portion into which a fingertip can be inserted for the purpose of facilitating the removal of the cap. ing. However, even though it is easy to remove the cap, the appearance of the cap is impaired by the hook-shaped portion protruding from the front end of the cap.
[0005]
[Problems to be solved by the invention]
The present invention solves the above-mentioned conventional problems, and does not impair the appearance of the cap, facilitates the insertion / removal of the back of the cap, and facilitates dimensional management in manufacturing. It is intended to provide a structure.
[0006]
In the back insertion structure of the cap of the present invention, “front” indicates the pen tip side of the writing instrument body and the opening end side of the cap, and “rear” indicates the tail end side of the writing instrument body and the cap. Then, it points to the closed end side.
[0007]
[Means for Solving the Problems]
[Claim 1]
The present invention provides a cap rearward insertion structure in which a recess 6 that opens axially rearward is provided at the rear end of the writing instrument body 1, and the outer end surface of the cap 4 is fitted to the inner surface of the recess 6. A tapered portion 5 that gradually decreases in diameter toward the opening end direction is provided on the outer surface of the opening end, and the front outer surface of the tapered portion 5 is fitted to the inner surface of the recess 6 in the rearward insertion state of the cap. It is a requirement that the rear outer surface is exposed (Claim 1).
[0008]
According to the present invention, since the outer surface shape of the opening end of the cap 4 is tapered toward the cap mounting direction by the tapered portion 5, the outer peripheral edge portion of the opening end of the cap 4 is recessed when the cap is inserted backward. 6 can be smoothly inserted into the inner surface of the recess 6 without being brought into contact with the inner peripheral edge of the opening end. That is, even if the cap 4 is inserted obliquely with respect to the axis of the writing instrument body 1, the inner peripheral edge of the opening end of the recess 6 is guided to the inclined outer surface of the tapered portion 5 during the insertion process. The four axes are straightened so that they coincide with the axis of the writing instrument body 1. Thereby, the insertion property to the recessed part 6 of the cap 4 improves remarkably.
[0009]
Further, according to the present invention, the front outer surface of the taper 5 is fitted into the inner surface of the recess 6 at the rear end of the writing instrument body 1 and the rear outer surface of the taper 5 of the remaining part is exposed to the outside in the state where the cap is inserted backward. I am letting. The outer surface of the tapered portion 5 has a shape that gradually increases in diameter toward the closed end direction (that is, the cap removal direction). Therefore, when removing the cap 4, it can remove easily by putting a finger | toe on the rear side outer surface of the taper 5 exposed outside.
[0010]
Further, the present invention provides a smart appearance without hindering the appearance by providing a conventional hook-like portion at the front end of the cap 4 in spite of the cap 4 satisfying easy detachability. Can maintain sex.
[0011]
In addition, the recessed part 6 provided in the rear end of the writing instrument main body 1 is, for example, a structure provided integrally with the rear end of the shaft tube 2, a structure provided at the rear end of the tail plug 7 attached to the rear end of the shaft tube 2, or the shaft tube. The structure etc. which are provided in the rear end of the other cap 8 attached to the rear end of 2 can be mentioned.
[0012]
[Claim 2]
In the cap back-insertion structure according to claim 1, the front end of the tapered portion 5 is in axial contact with the step portion 61 provided on the inner surface of the recess 6 in the cap back-insertion state (claim 2). preferable.
[0013]
Since the outer surface of the taper 5 of the cap 4 is inserted into the recess 6 of the writing instrument body 1 (Claim 1), when the cap 4 is strongly inserted into the recess 6 in the backward insertion process, the outer surface of the taper 5 There is a risk that the inner peripheral edge of the opening end of the recess 6 will come into strong contact and bite and damage the outer surface of the taper 5. However, by bringing the opening end of the cap 4 (that is, the front end of the taper 5) into axial contact with the stepped portion 61 on the inner surface of the recess 6, excessive insertion can be prevented, and there is no risk of damaging the outer surface, so the initial purchase. Can be maintained for a long time.
[0014]
[Claim 3]
In the cap back-and-forth structure according to claim 1 or 2, it is preferable that the thickness of the tapered portion 5 is gradually reduced toward the opening end (claim 3).
[0015]
By gradually reducing the thickness of the tapered portion 5 toward the opening end direction, elastic deformation in the radial direction of the opening end of the cap 4 is facilitated. As a result, the variation of the fitting dimension between the opening end outer surface of the cap 4 (that is, the front outer surface of the tapered portion 5) and the recess 6 inner surface, and the fitting dimension between the opening end of the cap 4 and the writing instrument body 1 on the pen tip side. Variations can be absorbed, and dimensional management in manufacturing the fitting portion of the writing instrument main body 1 and the cap 4 becomes easy.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0017]
[First embodiment]
1 and 2 show a first embodiment of the present invention.
[0018]
The cap back-insertion structure of the present embodiment is composed of a writing instrument body 1 and a cap 4. Further, the writing instrument main body 1 includes a shaft cylinder 2, an ink occlusion body 9, a pen body 3, and a tail plug 7.
[0019]
The shaft cylinder 2 is a cylindrical body obtained by injection molding of a synthetic resin, and an ink occlusion body 9 made of a heat-bonded processed body of a synthetic resin fiber bundle and impregnated with an aqueous whiteboard ink is contained therein. Be contained. A pen body 3 made of a rod-shaped fiber bundle resin processed body is attached to the front end of the shaft cylinder 2, and the front end of the pen body 3 projects forward from the front end of the shaft cylinder 2, and the pen The rear end of the body 3 is connected to the ink storage body 9. On the other hand, a tail plug 7 is closely fitted in the rear end opening of the shaft tube 2. The ink occlusion body 9 is held in the axial direction by the front end of the tail plug 7 and a locking step formed on the inner surface of the front portion of the shaft tube 2.
[0020]
The tail plug 7 includes a bottomed outer cylinder 71 that opens to the rear and a bottomed inner cylinder 72 that opens to the front. The closed end of the outer cylinder 71 and the opening end of the inner cylinder 72 are combined. It is the structure connected integrally by injection molding of resin.
[0021]
An annular recess 6 is formed between the inner surface of the outer cylinder 71 and the outer surface of the inner cylinder 72. A rear insertion portion is provided on the inner surface of the opening end of the recess 6. As shown in FIG. 2, the rear insertion portion is located in front of the chamfered portion 63, which is in front of the chamfered portion 63, and a chamfered portion 63 slidably contacting the front end outer surface of the tapered detail 5 when the cap is inserted backward. Are integrally formed with a fitting portion 62 that fits and a step portion 61 that is located in front of the fitting portion 62 and contacts the front end of the tapered portion 5.
[0022]
Further, a convex curved bottom wall of the inner cylinder 72 protrudes from the rear end surface of the outer cylinder 71 of the tail plug 7. This makes it difficult for the writing instrument body 1 to stand upright on a horizontal surface in a state where the pen tip is upward, so that the ink from the pen body 3 is prevented from descending and the writing hand is not thinned.
[0023]
The cap 4 is a synthetic resin injection-molded body in which an outer cap 41 and an inner cap 42 are integrally connected. The inner cap 42 is a bottomed cylindrical body, and an annular protrusion 43 that is airtightly fitted to the pen tip side outer surface of the shaft cylinder 2 is integrally formed on the inner surface thereof. On the other hand, the outer cap 41 is connected to the opening end of the inner cap 42, and a tapered surface or concave curved surface tapered portion 5 whose outer surface is reduced in diameter toward the front end is formed at the front end.
[0024]
When writing is used, the outer surface of the tip 5 is back-fitted with the inner surface of the opening end of the recess 6. On the other hand, when using non-writing, the inner surface of the tip 5 is connected to the outer surface of the shaft 2 on the pen tip side. Mated. Since the tapered portion 5 is gradually thinned toward the front end, elastic deformation in the radial direction is easy. As a result, it is possible to absorb the variation in the fitting dimension between the outer surface of the tip 5 and the inner surface of the recess 6 and the variation in the fitting dimension between the inner surface of the tip 5 and the front outer surface of the shaft tube 2. This is extremely advantageous.
[0025]
[Second Embodiment]
3 and 4 show a second embodiment of the present invention.
[0026]
The cap back insertion structure of the present embodiment is composed of a writing instrument main body 1 and two caps 4 and 8. Further, the writing instrument main body 1 includes a shaft cylinder 2, an ink occlusion body 9, and two pen bodies 3A and 3B. This is a double-headed writing instrument.
[0027]
The shaft cylinder 2 is made of a cylindrical body obtained by injection molding of a synthetic resin, and an ink occlusion body 9 made of a heat-bonded processed body of a synthetic resin fiber bundle is accommodated therein. Further, pen bodies 3A and 3B made of a rod-shaped fiber bundle resin processed body are attached to the front end and the rear end of the shaft tube 2, and one end of the pen body 3 projects to the outside and the other end is the ink storage body 9 respectively. Connected to. The caps 4 and 8 having the same shape are mounted on the pen bodies 3A and 3B, respectively.
[0028]
As in the first embodiment, the caps 4 and 8 are synthetic resin injection-molded bodies in which outer caps 41 and 81 and inner caps 42 and 82 are integrally connected. The inner caps 42 and 82 are bottomed cylindrical bodies, and annular projections 43 and 83 are formed integrally with the inner surface of the inner caps 42 and 82 so as to be airtightly fitted to the pen tip side outer surface of the shaft cylinder 2 as in the first embodiment.
[0029]
Further, the outer caps 41 and 81 are connected to the open ends of the inner caps 42 and 82, and like the first embodiment, at the front end thereof, a tapered surface shape or a concave curved surface shape whose outer surface is reduced in diameter toward the front end. The taper 5 is formed. An annular recess 6 is formed between the inner surface of the opening end of the outer cap 41, 81 and the inner cap 42, 82, and a rear insertion portion is formed on the inner surface of the opening end of the recess 6.
[0030]
When one cap 4 is fitted into the recess 6 of the other cap 8, the rear insertion portion of the other cap 8, as shown in FIG. A chamfered portion 63 that is in sliding contact with the outer surface of the tapered portion 5, a front portion of the chamfered portion 63, a fitting portion 62 that fits the front outer surface of one tapered portion 5, and a front portion of the fitting portion 62. , One tapered portion 5 and a step portion 61 with which the front end abuts.
[0031]
When the pen body 3 </ b> A side is used, the outer surface of the tapered portion 5 of the one cap 4 is back-fitted with the inner surface of the recess 6 of the other cap 8. On the other hand, when the pen body 3A side is not used (or when the pen body 3B side is used), the inner surface of the tapered portion 5 of the one cap 4 is fitted to the outer surface of the shaft cylinder 2 on the pen body 3A side. . Since the tapered portion 5 of the one cap 4 is gradually thinned toward the front end as in the first embodiment, elastic deformation in the radial direction is easy. Therefore, variation in the fitting dimension between the outer surface of the tapered portion 5 of the one cap 4 and the inner surface of the concave portion 6 of the other cap 8, and the inner surface of the tapered portion 5 of the one cap 4 and the pen of the shaft cylinder 2 Variations in fitting dimensions with the outer surface of the body 3A can be absorbed, which is extremely advantageous in terms of dimensional management.
[0032]
FIG. 3 shows a configuration in which the tapered portion 5 of one cap 4 is fitted into the recess 6 of the other cap 8. Since the caps 4 and 8 have the same structure, conversely, although not shown, the same effect can be obtained by inserting the tapered portion 5 of the other cap 8 into the recess 6 of the one cap 4.
[0033]
【The invention's effect】
According to the configuration of the first aspect of the present invention, the rear insertion structure of the cap facilitates attachment / detachment of the rear insertion of the cap without impairing the appearance of the cap.
[0034]
According to the configuration of the cap back-inserting structure of the present invention, the excessive insertion of the cap into the recess can be prevented, there is no possibility of damaging the outer surface of the cap, and the initial aesthetic appearance can be maintained for a long time.
[0035]
According to the configuration of the back insertion structure of the present invention, the dimensional management in manufacturing the writing instrument main body and the fitting portion of the cap becomes easy.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention. FIG. 2 is an enlarged view of a part A in FIG.
FIG. 3 is a longitudinal sectional view showing a second embodiment of the present invention. FIG. 4 is an enlarged view of part B of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Writing instrument main body 2 Shaft cylinder 3 Pen body 3A Pen body 3B Pen body 4 Cap 41 Outer cap 42 Inner cap 43 Annular projection 5 Tip 6 Recess 61 Step part 62 Fitting part 63 Chamfer part 7 End plug 71 Outer cylinder 72 Inner cylinder 8 cap 81 outer cap 82 inner cap 83 annular protrusion 9 ink occlusion body

Claims (3)

It is a cap back insertion structure in which a recess (6) that opens rearward in the axial direction is provided at the rear end of the writing instrument body (1), and the outer surface of the open end of the cap (4) is fitted to the inner surface of the recess (6), A tapered detail (5) that gradually decreases in diameter toward the opening end is provided on the outer surface of the opening end of the cap (4), and the front outer surface of the tapered detail (5) is disposed in the recessed portion (6) in the cap rearward insertion state. The cap back insertion structure characterized by being fitted to the inner surface of the cap and exposing the rear outer surface of the tapered portion (5). The cap back-insertion structure according to claim 1, wherein, in the cap back-insertion state, the front end of the tapered portion (5) is in axial contact with a step portion (61) provided on the inner surface of the recess (6). The cap back-insertion structure according to claim 1 or 2, wherein the thickness of the tapered portion (5) is gradually reduced toward the opening end.

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