JP2024095345A - Writing implements - Google Patents

Abstract

[Problem] To obtain a writing implement using a reduced amount of synthetic resin. [Solution] A writing implement (12) has a refill (14) and a plurality of peripheral members arranged around the refill (14), at least a portion of the peripheral members being formed from a paper-containing material that contains a paper component. [Selected Figure] Figure 2

Description

This disclosure relates to a writing instrument.

Patent document 1 describes a writing instrument in which a refill is housed inside a barrel and a synthetic resin tip is fitted to the tip of the barrel.

JP 2012-228812 A

In recent years, there has been a demand to reduce the amount of synthetic resin used in various products. It is desirable to use even less synthetic resin in writing instruments.

The objective of this disclosure is to obtain a writing instrument that uses a reduced amount of synthetic resin.

The writing instrument of the first embodiment has a writing core and a plurality of peripheral members arranged around the writing core, and at least a portion of the peripheral members is formed from a paper-containing material that contains a paper component.

In this writing instrument, at least some of the multiple peripheral components arranged around the writing core are formed from a paper-containing material. The paper-containing material contains paper components. Therefore, compared to a writing instrument in which all of the multiple peripheral components are formed from a material that does not contain paper components, such as synthetic resin, the amount of synthetic resin used can be reduced.

The second aspect is a writing instrument according to the first aspect, which is molded from the paper-containing material to form the peripheral member, and which has a female thread member with a female thread on its inner circumference and a housing member that houses the female thread member inside, and the outer circumferential surface of the female thread member contacts the inner circumferential surface of the housing member all around.

The female screw member is made of a paper-containing material, so the amount of synthetic resin used in the writing instrument can be reduced compared to when it is made of synthetic resin.

This writing instrument also has a housing member that houses the female screw member inside. When a male screw of another member is screwed into the female screw provided on the inner circumference of the female screw member, the housing member can suppress deformation and damage to the female screw member. The housing member can suppress the female screw member from spreading radially outward, suppressing a decrease in the fitting force when a male screw is screwed in.

The outer peripheral surface of the female screw member is in contact with the inner peripheral surface of the housing member all around.

This helps prevent deformation and damage around the entire circumference of the female threaded member.

In a third aspect, in the writing instrument of the first or second aspect, the writing core has a rearward surface facing the rear end side of the writing core at the tip side of the writing core, and the peripheral member has a contact portion that contacts the rearward surface from the rear end side of the writing core.

The contact portion of the peripheral member comes into contact with the rearward surface of the writing lead from the rear end side. As a result, even if the writing lead tries to move toward the rear end side, this movement is suppressed by the contact portion that comes into contact with the rearward surface.

The rearward surface is provided on the tip side of the writing lead. In other words, the writing lead is contacted by the contact portion of the surrounding member at its tip side. Therefore, bending of the writing lead can be suppressed compared to a configuration in which the portion that contacts the contact portion of the surrounding member is provided on the rear end side of the writing lead. Furthermore, even if there is variation in the length dimension of the writing lead, the effect of this variation is reduced and the position of the writing lead relative to the surrounding member is determined.

In a fourth aspect, the writing instrument according to any one of the first to third aspects has a paper-made cylindrical barrel and an inner member that is disposed inside the barrel and has a rib that is recessed into at least one of the axial end face and the inner peripheral surface of the barrel.

The ribs of the inner member are embedded into at least one of the axial end face and inner peripheral surface of the cylindrical barrel. Therefore, compared to a configuration without such ribs, the inner member is less likely to rotate relative to the barrel. Because the barrel is made of paper, a structure can be realized that allows the ribs of the inner member to easily embed themselves into it.

In a fifth aspect, in the writing implement of any one of the first to fourth aspects, the writing core has a flange portion whose outer diameter is partially larger in a portion of the axial direction, a female screw member having a female thread on the inner circumference and contacting the flange portion at the rear end side of the writing core, a male screw member formed of the paper-containing material and constituting a part of the peripheral member, having a male thread on the outer circumference and screwed into the female screw member, and a protrusion provided on the male screw member protruding in the axial direction of the male screw member, contacting the flange portion from the tip side of the flange portion when the male screw member is screwed into the female screw member, and sandwiching the flange portion in the axial direction between the male screw member and the female screw member.

The female screw member comes into contact with the flange of the writing core. When the male screw member is screwed into the female screw member, the protrusion of the male screw member comes into contact with the flange of the writing core at the tip side of the writing core. The protrusion clamps the flange between the clamping member, thereby clamping the flange and holding the writing core in the axial direction.

The male screw member is made of a paper-containing material, so the amount of synthetic resin used in the writing instrument can be reduced compared to when it is made of synthetic resin. Furthermore, the flange is clamped between the clamping member and the male screw member by the protrusion of the male screw member, so the flange can be clamped with less influence of dimensional variations in the male screw member compared to a structure without a protrusion, i.e., a structure in which the male screw member itself clamps the flange between the clamping member.

In a sixth aspect, the writing instrument according to any one of the first to fifth aspects has an opening/closing member that is formed from the paper-containing material and forms part of the peripheral member, and that has a plurality of opening/closing pieces that can be opened and closed by a hinge portion and that sandwich the writing core when closed.

The opening and closing member is made of a paper-containing material, so the amount of synthetic resin used in the writing implement can be reduced compared to when it is made of synthetic resin. The opening and closing piece is opened and closed at the hinge, and the writing lead is sandwiched in the closed state, so that the opening and closing member can be fixed to the writing lead while absorbing dimensional variations in the opening and closing member.

The technology disclosed herein makes it possible to obtain a writing instrument that uses a reduced amount of synthetic resin.

FIG. 1 is a front view showing a writing instrument according to a first embodiment. FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, showing the writing instrument of the first embodiment. FIG. 3 is a partially enlarged cross-sectional view of the writing instrument of the first embodiment. FIG. 4 is an exploded perspective view showing the writing instrument of the first embodiment. FIG. 5 is a perspective view showing a female screw member of the writing instrument of the first embodiment. FIG. 6 is a cross-sectional view showing a female screw member of the writing instrument of the first embodiment. FIG. 7 is a perspective view showing a male screw member of the writing instrument of the first embodiment. FIG. 8 is a cross-sectional view showing a male screw member of the writing instrument of the first embodiment. FIG. 9 is a cross-sectional view showing the writing core of the writing instrument of the first embodiment. FIG. 10 is a partially enlarged perspective view of the writing instrument of the first embodiment. FIG. 11 is a perspective view showing a state in which the writing lead is being replaced in the writing unit of the first embodiment. FIG. 12 is a partially enlarged cross-sectional view of a writing instrument according to the second embodiment. FIG. 13 is a perspective view showing a female screw member of a writing instrument according to the second embodiment. FIG. 14 is a partially enlarged perspective view of the writing instrument of the second embodiment. FIG. 15 is a partially enlarged cross-sectional view of a writing instrument according to a third embodiment. FIG. 16 is a perspective view showing a holding member of a writing implement according to the third embodiment with the opening/closing piece in a closed state. FIG. 17 is a perspective view showing a holding member of a writing implement according to the third embodiment with the opening/closing piece in an open state. FIG. 18 is a partially enlarged perspective view of a writing instrument according to a third embodiment. FIG. 19 is a partially enlarged perspective view of a writing instrument according to a third embodiment. FIG. 20 is a partially enlarged cross-sectional view of a writing instrument according to the fourth embodiment. FIG. 21 is a perspective view showing a holding member of a writing implement according to the fourth embodiment with the opening/closing piece in a closed state. FIG. 22 is a perspective view showing a holding member of a writing implement according to the fourth embodiment with the opening/closing piece in an open state. FIG. 23 is a partially enlarged perspective view of a writing instrument according to the fourth embodiment. FIG. 24 is a partially enlarged perspective view of a writing instrument according to the fourth embodiment.

Embodiments of the present disclosure will be described below with reference to the drawings. In the following description, the term "tip" refers to the writing tip of a writing instrument, for example, in the case where the writing instrument is a ballpoint pen, the end on the side where the writing ball is provided, and the term "rear end" refers to the end opposite the tip. Furthermore, reference numerals commonly used in each figure indicate common configurations even if they are not mentioned in the description of each figure.

Figure 1 shows a writing instrument 12 of the first embodiment. Figure 2 shows the writing instrument 12 of the first embodiment in a cross section taken along line 2-2 of Figure 1. Figure 3 shows a partially enlarged cross section of Figure 2. Figure 4 shows an exploded perspective view of the writing instrument 12 of the first embodiment.

The writing instrument 12 has a refill 14, a barrel 16, a barrel cover 18, a female screw member 20, and a male screw member 22. The refill 14 is an example of a writing lead. The barrel 16, the female screw member 20, and the male screw member 22 are an example of peripheral members arranged around the refill 14. Furthermore, the writing instrument 12 has a cap tube 24 and a cap cover 26.

In this embodiment, the shaft tube 16 and the cap tube 24 are made of paper and are formed into a cylindrical shape with both ends open. A cap lid 26 is attached to the tip of the cap tube 24, and a shaft lid 18 is attached to the rear end of the shaft tube 16. The shaft lid 18, the female screw member 20, the male screw member 22, the cap lid 26, and the like are molded, for example, from a paper-containing material. This paper-containing material is a material that contains paper components, and can be molded into a predetermined shape, for example, by paper injection molding (PIM: Pulp Injection Molding). In addition, paper obtained by a general paper manufacturing method other than paper injection molding is also included in the paper-containing material. The cap tube 24 and the shaft tube 16 may be made of paper.

The rear end of the cap tube 24 is adapted to fit into the male screw member 22 exposed from the tip of the barrel 16. The user can release this fit and remove the cap tube 24 from the male screw member 22, allowing writing with the writing instrument 12.

As shown in Figures 5 and 6, the female screw member 20 has a cylindrical portion 30, a reduced diameter portion 32, and a flange portion 34. The cylindrical portion 30 has a cylindrical shape, and the outer diameter of the cylindrical portion 30 is set to a predetermined outer diameter so that the cylindrical portion 30 is housed inside the shaft tube 16. The female screw member 20 is a member that is placed inside the shaft tube 16, and is also an example of an inner member.

The reduced diameter section 32 is formed in a truncated cone shape so that the diameter is reduced from the cylindrical section 30 toward the rear end. The flange section 34 extends radially outward from the tip side of the cylindrical section 30 in an annular shape. The outer diameter of the flange section 34 is equal to the outer diameter of the shaft tube 16.

A number of ribs 36 are formed on the outer peripheral surface of the cylindrical portion 30. Each of the ribs 36 is formed by partially protruding the outer peripheral surface of the cylindrical portion 30 radially outward. In the illustrated example, there are four ribs 36, which are formed at positions spaced apart at a predetermined interval (central angle of 90 degrees) in the circumferential direction of the cylindrical portion 30. In the first embodiment, the tip side of the ribs 36 is continuous with the flange portion 34. The ribs 36 are shaped so that the protruding height from the outer peripheral surface of the cylindrical portion 30 gradually decreases toward the rear end side.

The female screw member 20 is inserted into the barrel 16 from the rear end side (the reduced diameter portion 32 side). Then, as shown in FIG. 10, the rib 36 hits the tip surface 16T of the barrel 16 during insertion. When the female screw member 20 is inserted further, the rib 36 sinks into the tip surface 16T of the barrel 16 as shown in FIG. 3. When the flange portion 34 comes into contact with the tip surface 16T of the barrel 16, the female screw member 20 is inserted into the barrel 16 to a specified position.

When the female screw member 20 is inserted into the barrel 16 to a predetermined position, the female screw member 20 is housed inside the barrel 16. In other words, the barrel 16 is an example of a housing member of the technology disclosed herein.

As shown in FIG. 3, the refill 14 is inserted into the female screw member 20. The inside of the female screw member 20 has a large diameter portion 20L at the tip end and a small diameter portion 20S at the rear end. The inner diameter of the small diameter portion 20S is shorter than the inner diameter of the large diameter portion 20L. The step between the large diameter portion 20L and the small diameter portion 20S forms a contact portion 20T. As described below, the rearward surface 14B (see FIG. 9) of the refill 14 inserted into the female screw member 20 comes into contact with this contact portion 20T.

A female thread 38 is formed on the inner peripheral surface of the female thread member 20, specifically, on the tip end portion of the large diameter portion 20L. As can be seen from FIG. 3, the periphery of the portion of the female thread member 20 where the female thread 38 is formed (the tip end portion) is located inside the shaft tube 16. The outer peripheral surface of the cylindrical portion 30 of the female thread member 20 contacts the inner peripheral surface of the shaft tube 16 over the entire circumference.

As shown in Figs. 7 and 8, the male screw member 22 has a tip holding portion 40, a male screw portion 42, and a flange portion 44. As shown in Fig. 3, the tip holding portion 40 is formed in a truncated cone shape toward the tip side. The tip 52 of the refill 14 is located inside the tip holding portion 40, which is the portion that holds the tip 52 in this state.

A male thread 46 is formed on the outer circumferential surface of the male thread portion 42. By screwing the male thread 46 into the female thread 38 of the female thread member 20, the male thread member 22 can be fitted to the inside of the female thread member 20.

The diameter of the flange portion 44 is equal to the diameter of the shaft tube 16, i.e., the diameter of the flange portion 34 of the female threaded member 20. When the male thread 46 is screwed into the female thread 38 of the female threaded member 20, the flange portion 44 comes into contact with the flange portion 34 during the screwing process. When the male thread portion 42 of the male threaded member 22 is screwed into the female threaded member 20 to a predetermined position in this manner, the rear end surface 22B of the male threaded portion 42 faces the forward surface 14A of the refill 14, which will be described later, at a predetermined distance.

The male thread member 22 is provided with protrusions 48 that protrude from the rear end surface 42B of the male thread portion 42 toward the rear end side. In the illustrated example, the number of protrusions 48 is four, and they are formed at positions spaced apart at a predetermined interval (central angle of 90 degrees) in the circumferential direction of the male thread portion 42.

When the rear end surface 22B of the male screw member 22 faces the forward surface 14A of the refill 14, the protrusion 48 is designed to be slightly deformed when it comes into contact with this forward surface 14A. In other words, the protrusion 48 is pressed against the forward surface 14A while deforming. Then, the flange portion 56 of the refill 14 (see FIG. 9) is sandwiched in the axial direction between the protrusion 48 and the contact portion 20T of the female screw member 20.

As shown in FIG. 9, the refill 14 has an ink containing tube 50, a tip 52, and a joint 54. In this embodiment, the ink containing tube 50 is made of paper. Ink 58 is contained inside the ink containing tube 50. The ink 58 is prevented from leaking or drying out by a follower 60 provided inside the ink containing tube 50.

Even though the ink containing tube 50 is made of paper, it is constructed to have certain physical properties so that ink does not leak, seep out, dry out, deform, etc. Furthermore, the ink containing tube 50 is formed in a cylindrical shape with both ends open. The outer diameter of the ink containing tube 50 is smaller than the inner diameter of the barrel 16.

The tip 52 is held at the tip side of the ink containing tube 50 via a joint 54. A flange 56 with a larger diameter than the tip side is formed at the rear end side of the joint 54. The ink containing tube 50 is inserted into the inside of the flange 56 from the rear end side. The outer diameter of the flange 56 is larger than the outer diameter of the tip holding part 40 and the outer diameter of the ink containing tube 50. In other words, the flange 56 is a part of the refill 14 whose outer diameter is locally larger in the axial direction. The end face on the rear end side of the flange 56 is the rearward surface 14B that faces the rear end side of the refill 14.

When the refill 14 is inserted inside the barrel 16, the rearward surface 14B of the refill 14 comes into contact with the contact portion 20T, as shown in FIG. 3. This stops the refill 14 from being inserted into the barrel 16. In this state, the male thread portion 42 of the male thread member 22 can be placed against the inside of the female thread member 20 from the tip side, and the male thread member 22 can be screwed into the female thread member 20.

Next, the operation of this embodiment will be explained.

As shown in Figures 2 and 3, in the writing instrument 12 of this embodiment, the female screw member 20 is inserted from the tip side and housed inside the barrel 16. The refill 14 is inserted from the tip side inside the female screw member 20. Furthermore, the male thread 46 of the male screw member 22 is screwed into the female thread 38 of the female screw member 20, whereby the male screw member 22 is attached to the female screw member 20 and the refill 14 is held in a predetermined position relative to the barrel 16.

In this state, the protrusion 48 provided on the male screw member 22 contacts the forward surface 14A of the flange portion 56 of the refill 14 while deforming from the tip side. In addition, the contact portion 20T of the female screw member 20 contacts the rearward surface 14B of the refill 14. As a result, the flange portion 56 is sandwiched axially between the protrusion 48 and the contact portion 20T, so that the refill 14 can be securely held by the female screw member 20 and the male screw member 22.

When replacing the refill 14, as shown in FIG. 11, with the cap tube 24 removed from the male screw member 22, the male screw member 22 is loosened and removed from the female screw member 20. By removing the male screw member 22 in this manner, the refill 14 can be replaced. Even in this state, the female screw member 20 is held housed inside the shaft tube 16. By loosening the male screw member 22 and removing it from the female screw member 20 in this manner, the refill 14 can be easily replaced.

In this embodiment, the male screw member 22 is formed from a paper-containing material. It may be difficult to mold paper-containing materials with high dimensional accuracy, compared to, for example, resin materials. Therefore, when using a male screw member formed from a paper-containing material and having a structure without a protrusion 48, it may be difficult to sandwich the flange portion 56 in the axial direction between the male screw member and the female screw member 20. In contrast, in this embodiment, the male screw member 22 is provided with a protrusion 48, and the protrusion 48 can deform to achieve a state in which it is in reliable contact with the flange portion 56. In other words, even if there is dimensional variation in the male screw member 22 formed from a paper-containing material, the flange portion 56 can be reliably sandwiched between the male screw member 22 and the female screw member 20.

When the male screw member 22 is screwed into the female screw member 20, the screwing stops when the flange portion 44 of the male screw member 22 comes into contact with the flange portion 34 of the female screw member 20. Since the amount of screwing of the male screw member 22 into the female screw member 20 can be kept within a certain range, the protrusion 48 can be stably kept in contact with the forward surface 14A of the flange portion 56 while deforming.

The contact portion 20T of the female screw member 20 contacts the rearward surface 14B of the refill 14 from the rear end side. In other words, when the refill 14 is inserted inside the female screw member 20, it is supported by the female screw member 20 and prevented from moving toward the rear end side. The position where the refill 14 is supported by the female screw member 20 is the position of the flange portion 56, i.e., the position on the tip side of the refill 14.

In this embodiment, the ink containing tube 50 of the refill 14 is made of paper. It may be difficult to mold paper materials with high dimensional accuracy, compared to, for example, resin materials. Therefore, for example, in a configuration in which the refill 14 is supported by the barrel 16 or the like at the rear end side of the refill 14, i.e., the rear end side of the ink containing tube 50, the influence of dimensional variation of the refill 14 is large, and there is a risk of large variation in the position of the refill 14 relative to the barrel 16. In contrast, in this embodiment, the refill 14 contacts the contact portion 20T of the female screw member 20 at the rearward surface 14B of the refill 14, which is the tip side position. Therefore, the influence of dimensional variation of the refill 14 is reduced, and the refill 14 can be fixed to the female screw member 20, i.e., the barrel 16, at a certain range of positions.

When the writing instrument 12 is in use, writing pressure acts on the refill 14. In a configuration using a paper ink containing tube 50, in which the rear end of the ink containing tube 50 is supported by the barrel 16, there is a risk that the ink containing tube 50 will bend due to writing pressure. In contrast, in this embodiment, the writing pressure component toward the rear end is supported by the female screw member 20 at the tip side of the refill 14. Since writing pressure does not act on the ink containing tube 50 on the rear end side of the flange 56, essentially, bending of the ink containing tube 50, i.e., the refill 14, can be suppressed.

Since the refill 14 and the female screw member 20 are in contact with each other, the writing pressure during use of the writing instrument 12 may also act on the female screw member 20 from the refill 14. In this embodiment, the female screw member 20 is molded from a paper-containing material. The paper-containing material has a lower strength than, for example, a resin material, and may be easily deformed or damaged by an external force. Here, in this embodiment, the female screw member 20 is housed in the shaft tube 16. Since the female screw member 20 is held by the shaft tube 16 from the outer periphery, even if an external force acts on the female screw member 20, the deformation or damage of the female screw member 20 is suppressed. The male screw member 22 is screwed into the female screw member 20, but the female screw member 20 is prevented from spreading or cracking radially outward, which also suppresses a decrease in the screw-in engagement force.

In particular, in this embodiment, the outer peripheral surface of the cylindrical portion 30 of the female screw member 20 is in contact with the inner peripheral surface of the shaft tube 16 over the entire circumference. Therefore, deformation and damage to the female screw member 20 can be suppressed over the entire circumference.

A rib 36 is formed on the outer peripheral surface of the female screw member 20. When the male screw member 22 is inserted from the tip side of the female screw member 20, the rib 36 is embedded into the tip surface 16T of the shaft tube 16. This fixes the male screw member 22 to the female screw member 20 in the circumferential direction.

In the writing instrument 12 of the first embodiment, the barrel 16 is made of paper. The female screw member 20 is formed of a paper-containing material. In this case, it is also possible to simply press the male screw member 22 into the barrel 16 without forming a rib 36 on the female screw member 20. However, when the male screw member 22 rotates relative to the female screw member 20, for example, when replacing the refill 14 as shown in FIG. 11, the torque of this rotation acts on the female screw member 20, and the female screw member 20 may rotate relative to the barrel 16. In contrast, in this embodiment, the rib 36 is recessed into the tip surface of the barrel 16, making it difficult for the male screw member 22 to rotate relative to the female screw member 20.

In addition, because the shaft tube 16 is made of paper, it is possible to realize a structure in which the rib 36 of the female screw member 20 can be easily inserted into the shaft tube 16, compared to a structure made of, for example, synthetic resin.

In the writing instrument 12 of the first embodiment, the female screw member 20, the male screw member 22, and the shaft cover 18 are made of a paper-containing material. In addition, the shaft tube 16 and the ink reservoir tube 50 are made of paper. Therefore, the amount of synthetic resin used in the writing instrument 12 can be reduced compared to a configuration in which these components are made of synthetic resin.

Even if one of the female screw member 20 and the male screw member 22 is made of a paper-containing material and the other is made of synthetic resin, the amount of synthetic resin used can be reduced compared to a configuration in which both are made of synthetic resin.

Furthermore, in the writing instrument 12 of the technology disclosed herein, the cap tube 24 is made of paper, and the cap lid 26 is molded from a paper-containing material. Therefore, the amount of synthetic resin used can be reduced compared to a configuration in which both of these are made of synthetic resin.

Next, the second embodiment will be described. In the second embodiment, the same elements, members, etc. as those in the first embodiment are given the same reference numerals as those in the first embodiment, and detailed descriptions thereof will be omitted. In addition, since the overall configuration of the writing instrument 212 in the second embodiment is the same as that of the writing instrument 12 in the first embodiment, illustrations thereof will be omitted.

As shown in Figures 12 and 13, in the writing instrument 212 of the second embodiment, the rib 216 in the female screw member 214 is formed longer in the longitudinal direction of the female screw member 214 than the rib 36 in the first embodiment.

In addition, in the second embodiment, the rib 216 is spaced apart from the flange portion 34 at the tip side.

Even in the writing instrument 212 of the second embodiment configured in this way, as shown in FIG. 14, the female screw member 214 is inserted into the barrel 16. In this case, the rib 216 is embedded into the inner peripheral surface 16N of the barrel 16. Then, the flange portion 34 comes into contact with the tip surface 16T of the barrel 16, so that the female screw member 214 is inserted into the barrel 16 to a predetermined position.

The rib 216 of the second embodiment is longer in the longitudinal direction of the female screw member 214 than the rib 36 of the first embodiment. This provides a high effect in suppressing the relative rotation of the female screw member 214 with respect to the shaft tube 16.

Next, the third embodiment will be described. In the third embodiment, elements, members, etc. similar to those in the first or second embodiment are given the same reference numerals as in the first or second embodiment, and detailed descriptions thereof will be omitted.

As shown in Figures 15 to 17, the writing instrument 312 of the third embodiment has a retaining member 314. The retaining member 314 is made of a paper-containing material similar to the female screw member 20 of the first embodiment. The retaining member 314 is an example of a peripheral member that is arranged around the refill 14, and is also an example of an inner member.

The retaining member 314 is provided with a cylindrical portion 316. The cylindrical portion 316 has an outer diameter that is accommodated inside the shaft tube 16, similar to the cylindrical portion 30 of the female screw member 20 of the first embodiment (see FIG. 3). As shown in FIGS. 18 and 19, the refill 14 is inserted inside the cylindrical portion 316.

Furthermore, an opening/closing member 318 is provided at the rear end side of the cylindrical portion 316. The opening/closing member 318 has the same outer diameter as the cylindrical portion 30, and has a semi-cylindrical semi-cylinder portion 320 that continues from the cylindrical portion 316 to the rear end side, and a pair of opening/closing pieces 322 attached to the semi-cylinder portion 320. The opening/closing pieces 322 can be rotated in the direction indicated by the arrow R1 (see FIG. 17) relative to the semi-cylinder portion 320 by the hinge portion 324. The opening/closing pieces 322 can be deformed between the closed state shown in FIG. 16 and FIG. 18 and the open state shown in FIG. 17 and FIG. 19, that is, can be opened and closed. In the third embodiment, the hinge portion 324 is formed along the axial direction (longitudinal direction) of the female screw member 20.

One side of the opening/closing piece 322 has a mating protrusion 326, and the other side has a mating recess 328. When the opening/closing piece 322 is in the closed state, the mating protrusion 326 is mated with the mating recess 328. When the opening/closing piece 322 is in the closed state, the opening/closing piece 322 and the semi-cylindrical portion 320 form an integrated shape that continues from the cylindrical portion 316 to the rear end side with a constant outer diameter.

In addition, in the writing instrument 312 of the third embodiment, a tip portion 330 is integrally provided on the tip side of the holding member 314 (the tip side of the flange portion 34). This tip portion 330 can hold the tip 52, similar to the male screw member 22 of the first and second embodiments. In essence, in the writing instrument 312 of the third embodiment, the cylindrical portion 316 and the opening and closing member 318 of the holding member 314 are housed inside the shaft tube 16, and the refill 14 is housed inside them, so that it functions similarly to the female screw member 20 of the first embodiment. Then, the tip portion 330 continuing from the cylindrical portion 316 holds the tip 52 of the refill 14. Therefore, the holding member 314 of the third embodiment has a structure in which a member that performs the function of the female screw member 20 of the first embodiment and a member that performs the function of the male screw member 22 are integrally formed.

A contact portion 318T is provided on the inner peripheral surface of the opening/closing piece 322. When the opening/closing piece 322 is in the closed state, the contact portion 318T is formed in a position that contacts the rearward surface 14B of the refill 14 with a small gap therebetween, similar to the contact portion 20T of the first embodiment.

A contact surface 316T that contacts the forward surface 14A of the refill 14 is formed on the inner circumferential surface of the cylindrical portion 316. The contact surface 316T contacts the forward surface 14A of the refill 14.

As shown in FIG. 18, in the writing instrument 312 of the third embodiment configured as described above, the refill 14 can be inserted from the rear end side of the holding member 314 with the opening/closing piece 322 of the opening/closing member 318 in the open state. When the refill 14 is inserted to a predetermined position, the front surface 14A of the refill 14 comes into contact with the contact surface 316T, and the insertion stops.

In this state, the opening and closing piece 322 can be rotated around the hinge portion 324 to close the case as shown in FIG. 19. In this state, the holding member 314 can be inserted into the barrel 16, and the refill 14 can be attached to the barrel 16 at a predetermined position.

When the opening/closing piece 322 is in the closed state, the refill 14 is held by the holding member 314, so even in the third embodiment, the effect of variations in the dimensions of the refill 14 is reduced, and the refill 14 can be fixed at a certain position relative to the holding member 314, i.e., the barrel 16.

In addition, when the writing instrument 12 is in use, the component of writing pressure directed toward the rear end is supported by the retaining member 314 at the tip end of the refill 14, thereby making it possible to suppress bending of the ink containing tube 50, i.e., the refill 14.

In the third embodiment, the opening/closing piece 322 provided on the holding member 314 can be opened and closed by a hinge portion 324, whereby the refill 14 is sandwiched from the outside and fixed to the holding member 314. Here, in a configuration in which the writing lead is screwed into the holding member made of a paper-containing material by, for example, fitting a screw, it may be difficult to securely hold the refill 14 in a predetermined position in the fitted state because the paper-containing material has a lower strength than the resin material. In contrast, in the third embodiment, the refill 14 is sandwiched and fixed from the outside by the holding member 314, so the refill 14 can be securely held in a predetermined position relative to the holding member 314.

Moreover, in the third embodiment, the refill 14 is clamped and fixed from both the leading end and the trailing end by a single holding member 314. Therefore, compared to a configuration in which the refill 14 is clamped and fixed by multiple members, the refill 14 can be fixed to the holding member 314 with high positional accuracy.

Next, the fourth embodiment will be described. In the fourth embodiment, elements, members, etc. similar to those of any of the first to third embodiments are given the same reference numerals as those of any of the first to third embodiments, and detailed descriptions thereof will be omitted.

As shown in Figures 20 to 22, the writing instrument 412 of the fourth embodiment has a holding member 414 made of a paper-containing material, similar to the third embodiment.

The cylindrical portion 416 of the holding member 414 is shorter in the axial direction than the cylindrical portion 316 of the third embodiment. In the fourth embodiment, the shape of the opening/closing member 418 is different from that of the opening/closing member 318 of the third embodiment. Specifically, the opening/closing direction of the opening/closing pieces 422 is different from that of the third embodiment. That is, the hinge portion 424 is formed along the circumferential direction of the cylindrical portion 416. The pair of opening/closing pieces 422 can each rotate around the hinge portion 424 in the direction indicated by the arrow R2.

As shown in Figs. 22 and 23, each opening/closing piece 422 is formed in a semi-cylindrical shape with a central angle of 180 degrees. As shown in Figs. 21 and 24, when the opening/closing piece 422 is in the closed state, it has a cylindrical shape with the same outer diameter as the cylindrical portion 316. In the fourth embodiment, as shown in Fig. 22, a contact portion 318T and a contact surface 316T are formed on the inner peripheral surface of the opening/closing piece 422. Furthermore, a mating protrusion 428 is formed on one side of the opening/closing piece 422, and a mating recess 430 is formed on the other side of the opening/closing piece 422. When the opening/closing piece 422 is in the closed state, the mating protrusion 428 is mated with the mating recess 430, as shown in Figs. 21 and 24.

Even in the writing implement 412 of the fourth embodiment configured as described above, the refill 14 can be inserted from the rear end side of the holding member 414 with the opening/closing piece 422 of the opening/closing member 418 in the open state. Then, when the refill 14 is inserted to a predetermined position, the opening/closing piece 422 is rotated around the hinge portion 424 to be in the closed state, so that the contact surface 316T contacts or faces the front surface 14A of the refill 14, and the contact portion 318T contacts or faces the rear surface 14B of the refill 14. As a result, the refill 14 is held in the axial direction by the holding member 414. Since the refill 14 contacts the contact portion 20T of the holding member 414 at the rear surface 14B of the refill 14, which is the position on the tip side, even in the fourth embodiment, the effect of variation in the dimensions of the refill 14 is reduced, and the refill 14 can be fixed to the holding member 414, i.e., the barrel 16, at a position within a certain range.

In addition, when the writing instrument 12 is in use, the component of writing pressure directed toward the rear end is supported by the retaining member 414 at the tip end of the refill 14, thereby suppressing bending of the ink containing tube 50, i.e., the refill 14.

In the fourth embodiment, the opening and closing piece 422 provided on the holding member 414 can be opened and closed by the hinge portion 424, and the refill 14 is clamped from the outside and fixed to the holding member 414. Therefore, the refill 14 can be securely held in a predetermined position relative to the holding member 314.

Moreover, in the fourth embodiment, the refill 14 is clamped and fixed from both the leading end and the trailing end by a single holding member 414. Therefore, compared to a configuration in which the refill 14 is clamped and fixed by multiple members, the refill 14 can be fixed to the holding member 414 with high positional accuracy.

12 Writing implement 14 Refill 14A Front surface 14B Rear surface 16 Barrel tube 16N Inner peripheral surface 16T Tip surface 18 Barrel lid 20 Female thread member 20L Large diameter portion 20S Small diameter portion 20T Contact portion 22 Male thread member 22B Rear end surface 24 Cap tube 26 Cap lid 30 Cylindrical portion 32 Reduced diameter portion 34 Flange portion 36 Rib 38 Female thread 40 Tip holder 42 Male thread portion 42B Rear end surface 44 Flange portion 46 Male thread 48 Protrusion 50 Ink containing tube 52 Tip 54 Joint 56 Flange portion
212 Writing implement 214 Female screw member 216 Rib 312 Writing implement 314 Holding member 316 Cylindrical portion 316T Contact surface 318 Opening/closing member 318T Contact portion 320 Semi-cylindrical portion 322 Opening/closing piece 324 Hinge portion 326 Fitting protrusion 328 Fitting recess 330 Tip portion 412 Writing implement 414 Holding member 416 Cylindrical portion 418 Opening/closing member 422 Opening/closing piece 424 Hinge portion 428 Fitting protrusion 430 Fitting recess

Claims (6)

A writing tip;
A plurality of peripheral members arranged around the writing core;
having
At least a portion of the peripheral member is formed from a paper-containing material that contains a paper component.
Writing implements. A female screw member formed of the paper-containing material to form the peripheral member and having a female screw on an inner periphery;
A housing member that houses the female screw member therein;
having
The outer circumferential surface of the female screw member is in contact with the inner circumferential surface of the housing member over the entire circumference.
2. The writing instrument of claim 1. The writing core has a rearward surface facing a rear end side of the writing core at a tip side of the writing core,
The peripheral member has a contact portion that contacts the rear surface from the rear end side of the writing core.
2. The writing instrument of claim 1. A cylindrical paper barrel and
an inner member disposed inside the barrel and including a rib recessed into at least one of an axial end face and an inner circumferential surface of the barrel;
2. The writing instrument of claim 1, comprising: The writing core has a flange portion in which the outer diameter is partially larger in a part of the axial direction,
A female screw member having a female screw on an inner circumference and contacting the flange portion at a rear end side of the writing tip;
a male screw member formed of the paper-containing material and constituting a part of the peripheral member, the male screw member having a male screw on an outer periphery thereof and being screwed into the female screw member;
a protrusion provided on the male screw member protruding in an axial direction of the male screw member, the protrusion contacting the flange portion from a tip side of the flange portion when the male screw member is screwed into the female screw member to sandwich the flange portion in the axial direction between the male screw member and the female screw member;
The writing instrument according to any one of claims 1 to 4, comprising: an opening/closing member formed of the paper-containing material and constituting a part of the peripheral member, the opening/closing member being openable and closable by a hinge portion and including a plurality of opening/closing pieces that sandwich the writing core in a closed state;
2. The writing instrument of claim 1, comprising: