Writing instrument

Abstract

The present invention is provided with: a shaft tube (1) extending in the axial direction along a central axis; and a writing member disposed inside the shaft tube (1), the shaft tube (1) having a plurality of fibrous protrusions (6) protruding radially outward from the outer peripheral surface of the shaft tube (1), the fibrous protrusions (6) being provided side by side on the outer peripheral surface, each of the fibrous protrusions (6) having: a plurality of ribs extending in a predetermined direction when viewed from the radially outer side, the plurality of ribs (6) being configured so as to extend in the predetermined direction when viewed from the radially outer side; the plurality of first electrodes are arranged side by side in a width direction orthogonal to a predetermined direction. And a step portion extending in the predetermined direction and disposed between the ribs adjacent in the width direction or at the ends of the ribs in the width direction.

Description

Technical Field

[0001] The present invention relates to a writing instrument.

[0002] This application claims priority to Japanese Patent Application No. 2022-166180 filed in Japan on October 17, 2022, the content of which is incorporated herein by reference. Background Art

[0003] Conventionally, as a writing instrument such as a ballpoint pen, a writing instrument is known that includes a shaft tube made of resin or the like, writing members such as a refill disposed inside the shaft tube, and a grip portion made of rubber or the like that is fitted to the outer peripheral surface of the shaft tube. The writing instrument described in Patent Document 1 has grooves for anti-slip formed in the grip portion.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent No. 4043305 Gazette Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] There is room for improvement in such a writing instrument in terms of further improving the design and the usability.

[0009] In addition, it is difficult to impart a visual and tactile feeling to the outer peripheral surface of the shaft tube as if it were made of an actual fabric or the like.

[0010] One object of the present invention is to provide a writing instrument that can impart a feeling as if it were made of a fabric or the like to the outer peripheral surface of the shaft tube, has a good appearance, can improve the design, and has a good touch and improved usability.

[0011] Solutions for Solving the Problems

[0012] The present invention provides the following solutions to solve the above technical problems.

[0013] [Solution 1 of the Present Invention]

[0014] A writing instrument includes: a shaft tube that extends in the axial direction along a central axis; and a writing member disposed inside the shaft tube, wherein the shaft tube has fibrous protrusions that project radially outward from the outer peripheral surface of the shaft tube, a plurality of the fibrous protrusions are arranged side by side on the outer peripheral surface, and each of the fibrous protrusions has: a plurality of rib portions that extend in a predetermined direction when viewed from the radially outer side and are arranged side by side in a width direction orthogonal to the predetermined direction; and a step portion that is disposed between the rib portions adjacent in the width direction or at an end portion in the width direction of the rib portion and extends in the predetermined direction.

[0015] In the writing instrument of the present invention, a plurality of fibrous protrusions are provided on the outer peripheral surface of the shaft cylinder. Each fibrous protrusion has a plurality of rib portions extending in a specified direction and stepped portions disposed between the rib portions adjacent in the width direction or at the widthwise ends of the rib portions. By adopting such a plurality of fibrous protrusions, it is possible to give users and the like a feeling as if the outer peripheral surface of the shaft cylinder is made of a fabric, cloth, or a mat woven with rush or the like (hereinafter abbreviated as fabric or the like).

[0016] Specifically, through the plurality of rib portions and stepped portions, it is possible to approximate the shadow of the fibrous protrusion to the shadow of yarn, rush, or the like which are elements of a fabric or the like. Therefore, it is possible to give users of the writing instrument and the like a visual feeling as if the outer peripheral surface of the shaft cylinder is made of a fabric or the like.

[0017] In addition, when a user of the writing instrument touches the fibrous protrusion with a fingertip or the like, through the plurality of rib portions and stepped portions, it is possible to give a tactile feeling as if touching the surface of an actual fabric or the like. Specifically, for example, a directional tactile sensation can be obtained as if the fibers on the surface of yarn, rush, or the like extend in a specified direction.

[0018] In addition, the outer peripheral surface of the shaft cylinder contacts the "interdigital space" between the base of the index finger and the base of the thumb in the user's hand when the writing instrument is in use. In this writing instrument, by providing the fibrous protrusions, it is possible to improve the tactile sensation of the shaft cylinder at the interdigital space.

[0019] According to the above, according to the present invention, it is possible to give the outer peripheral surface of the shaft cylinder a feeling as if it is made of an actual fabric or the like, with good appearance, improved design, and good tactile sensation, thus improving the usability.

[0020] 〔Aspect 2 of the present invention〕

[0021] In the writing instrument according to Aspect 1, in the fibrous protrusion, the amount of protrusion radially outward of the middle portion located between the two end portions in the specified direction is larger than that of the two end portions.

[0022] 〔Aspect 3 of the present invention〕

[0023] In the writing instrument according to Aspect 1 or 2, in the fibrous protrusion, the amount of protrusion radially outward of the middle portion located between the two end portions in the width direction is larger than that of the two end portions.

[0024] In this case, the shape of the fibrous protrusions can be made more similar to the shape of the yarns constituting an actual fabric or the like, or the exposed portions of rush or the like. The outer peripheral surface of the shaft tube can be more stably imparted with visual and tactile sensations as if it were made of an actual fabric or the like. The effects of improving the design and usability become more prominent.

[0025] 〔Aspect 4 of the present invention〕

[0026] The writing instrument according to any one of Aspects 1 to 3, wherein the plurality of ribs include: an outer rib disposed at an end portion on the outer side in the width direction of the fibrous protrusion; and an inner rib disposed on the inner side in the width direction relative to the outer rib, and the inner rib has a portion with a larger amount of protrusion radially outward than the outer rib.

[0027] In this case, in the fibrous protrusion, the inner rib located on the inner side in the width direction protrudes significantly more radially outward than the outer rib located at the outer end portion in the width direction. Thereby, the shape of the fibrous protrusion can be made more similar to the shape of the yarns constituting an actual fabric or the like, or the exposed portions of rush or the like. Therefore, the above-described effects become more prominent.

[0028] 〔Aspect 5 of the present invention〕

[0029] The writing instrument according to Aspect 4, wherein a plurality of the inner ribs are arranged side by side in the width direction.

[0030] 〔Aspect 6 of the present invention〕

[0031] The writing instrument according to Aspect 5, wherein the amounts of protrusion of the plurality of inner ribs radially outward are different from each other.

[0032] In this case, the fibrous protrusion has a plurality of inner ribs arranged side by side in the width direction, and the amounts of protrusion (i.e., height dimensions) of the respective inner ribs radially outward are different from each other. Thereby, the shape of the fibrous protrusion can be made more similar to the shape of the yarns constituting an actual fabric or the like, or the exposed portions of rush or the like. Therefore, the above-described effects become more prominent.

[0033] 〔Aspect 7 of the present invention〕

[0034] The writing instrument according to Scheme 5 or 6, wherein the plurality of the inner ribs include: a first inner rib, among the plurality of the inner ribs, the amount of protrusion radially outward at the central portion in the specified direction of the first inner rib is the largest; and a second inner rib, the amount of protrusion radially outward at the central portion in the specified direction of the second inner rib is smaller than that of the first inner rib, and the amount of protrusion radially outward at the end portion in the specified direction of the second inner rib is larger than that of the first inner rib at the end portion in the specified direction.

[0035] In this case, the inclinations and shapes of the first inner rib and the second inner rib among the plurality of inner ribs of the fibrous protrusion are different from each other. Thereby, the shape of the fibrous protrusion can be made more similar to the shape of the yarns constituting an actual fabric, etc., and the exposed portions of rush, etc. Therefore, the above-described effects become more obvious.

[0036] 〔Aspect 8 of the present invention〕

[0037] The writing instrument according to any one of Aspects 1 to 7, wherein the plurality of the fibrous protrusions include: an axial protrusion extending along the axial direction; and a circumferential protrusion extending along the circumferential direction, and the axial protrusions and the circumferential protrusions are alternately arranged in at least one of the axial direction and the circumferential direction.

[0038] In this case, for example, the axial protrusions function as warp yarns and the circumferential protrusions function as weft yarns, and a visual and tactile feeling as if they are alternately interwoven can be imparted to the shaft tube. A feeling as if the outer peripheral surface of the shaft tube is constituted by an actual fabric, etc. can be more effectively imparted.

[0039] 〔Aspect 9 of the present invention〕

[0040] The writing instrument according to any one of Aspects 1 to 8, wherein the plurality of the fibrous protrusions include: an axial protrusion extending along the axial direction; and a circumferential protrusion extending along the circumferential direction, and the amount of protrusion radially outward of the axial protrusion is larger than that of the circumferential protrusion.

[0041] In this case, for example, the axial protrusions function as warp yarns and the circumferential protrusions function as weft yarns. Since the amount of protrusion of the axial protrusions is larger than that of the circumferential protrusions, among the outer peripheral surface of the shaft tube, the warp yarns (axial protrusions) can be more emphasized visually and tactilely than the weft yarns (circumferential protrusions). Therefore, the degree of freedom in design can be further improved and the touch can be made better.

[0042] 〔Aspect 10 of the present invention〕

[0043] The writing instrument according to any one of Aspects 1 to 9, wherein the plurality of fibrous protrusions include: a plurality of axial protrusions extending axially and having different shapes; and a plurality of circumferential protrusions extending circumferentially and having different shapes.

[0044] In this case, for example, the axial protrusions function as warp threads and the circumferential protrusions function as weft threads. If there are a plurality of axial protrusions and a plurality of circumferential protrusions, a visually and tactilely similar feeling to that formed by an actual fabric or the like can be more effectively imparted to the outer peripheral surface of the barrel.

[0045] 〔Aspect 11 of the present invention〕

[0046] The writing instrument according to any one of Aspects 1 to 10, wherein the fibrous protrusions have a textured surface on their surface.

[0047] In this case, since the fibrous protrusions have a textured surface on their surface, a finer, matte-like shadow can be imparted to the fibrous protrusions, or a smooth and comfortable touch can be imparted. Therefore, the design can be further improved and the usability can be further enhanced.

[0048] 〔Aspect 12 of the present invention〕

[0049] The writing instrument according to any one of Aspects 1 to 11, wherein the barrel has a parting line extending axially and disposed on the outer peripheral surface of the barrel, and the plurality of fibrous protrusions include a plurality of circumferential protrusions extending circumferentially, and at least one of the plurality of circumferential protrusions is located on the parting line.

[0050] For example, in the case of injection molding a resin barrel between a pair of molds, the parting line extends axially along the opposing surface (split surface) of the pair of molds on the outer peripheral surface of the barrel. In a configuration different from the above, for example, in the case where a fibrous protrusion (axial protrusion) extending axially is disposed on the parting line, when the pair of molds are separated from each other after injection molding, the axial protrusion on the parting line may rub against the mold, sometimes causing tearing or burrs.

[0051] On the other hand, as in the above configuration, in the case where a circumferential protrusion extending circumferentially is located on the parting line, since the pair of molds are separated from each other in the direction along which the circumferential protrusion extends, the above-described problems such as tearing and burrs can be suppressed. Therefore, even if a parting line necessary for manufacturing is provided on the outer peripheral surface of the barrel, interruption or unnaturalness of the pattern such as a fabric on the parting line can be suppressed, and the design can be further improved.

[0052] 〔Aspect 13 of the present invention〕

[0053] The writing instrument according to Scheme 12, wherein the parting line has a textured surface extending axially.

[0054] In this case, even if a parting line necessary for manufacturing is provided on the outer peripheral surface of the shaft cylinder, the parting line can be made inconspicuous. Therefore, the designability can be further improved.

[0055] 〔Aspect 14 of the present invention〕

[0056] The writing instrument according to any one of Aspects 1 to 13 further includes: a clip extending axially and disposed opposite to the shaft cylinder from the radially outer side, and a plurality of the fibrous protrusions include axial protrusions that overlap the clip and extend axially when viewed radially.

[0057] In this case, when the writing instrument is held or removed from a pocket or the like of the user's clothes or the like using the clip, the fabric of the pocket or the like easily slides between the clip and the axial protrusion, and the fabric can be stably clamped. The writing instrument is easily hung on a pocket or the like and is also easily removed, so the usability is good.

[0058] 〔Aspect 15 of the present invention〕

[0059] The writing instrument according to any one of Aspects 1 to 14 further includes: a grip portion fitted to the outer peripheral surface of the shaft cylinder, and the fibrous protrusions are disposed in a portion of the outer peripheral surface of the shaft cylinder other than the portion covered by the grip portion.

[0060] In this case, an anti-slip function during writing or the like is obtained by the grip portion, and the fibrous protrusions are not blocked by the grip portion. Therefore, the above-described effects can be obtained more stably.

[0061] Advantages of the Invention

[0062] The writing instrument according to the aspect of the present invention can give the outer peripheral surface of the shaft cylinder a feeling as if it is made of a fabric or the like, has a good appearance and can improve the designability, and has a good touch and improved usability. Description of the Drawings

[0063] Figure 1 It is a side view showing the writing instruments of the first embodiment and the second embodiment, omitting the illustration of the fibrous protrusions, the parting line, etc. disposed on the outer peripheral surface of the shaft cylinder.

[0064] Figure 2 It is a plan view showing the outer peripheral surface of the shaft cylinder of the writing instrument of the first embodiment in an unfolded manner and an enlarged view showing a part of the plan view in an enlarged manner.

[0065] Figure 3 It is Figure 2A diagram showing an enlarged view of part III, specifically, a top view showing the first axial protrusion among multiple fibrous protrusions.

[0066] Figure 4 Is a diagram that enlarges Figure 2 Part IV, specifically, a top view showing the second axial protrusion among multiple fibrous protrusions.

[0067] Figure 5 Is a diagram that enlarges Figure 2 Part V, specifically, a top view showing the first circumferential protrusion among multiple fibrous protrusions.

[0068] Figure 6 Is a diagram that enlarges Figure 2 Part VI, specifically, a top view showing the second circumferential protrusion among multiple fibrous protrusions.

[0069] Figure 7 Is a three-dimensional view showing an example of a fibrous protrusion, specifically showing Figure 3 The first axial protrusion.

[0070] Figure 8 Is a diagram showing Figure 3 The cross-sectional view of the VIII-VIII section.

[0071] Figure 9 Is a diagram showing Figure 3 The cross-sectional view of the IX-IX section.

[0072] Figure 10 Is a diagram showing Figure 3 The cross-sectional view of the X-X section.

[0073] Figure 11 Is a diagram showing Figure 3 The cross-sectional view of the XI-XI section.

[0074] Figure 12 Is a diagram showing Figure 3 The cross-sectional view of the XII-XII section.

[0075] Figure 13 Is a diagram showing Figure 3 The cross-sectional view of the XIII-XIII section.

[0076] Figure 14 Is a diagram showing Figure 4 The cross-sectional view of the XIV-XIV section.

[0077] Figure 15 Is a diagram showing Figure 4 The cross-sectional view of the XV-XV section.

[0078] Figure 16 Is a diagram showingFigure 4 Cross-sectional view of the XVI-XVI section.

[0079] Figure 17 It represents Figure 4 Cross-sectional view of the XVII-XVII section.

[0080] Figure 18 It represents Figure 4 Cross-sectional view of the XVIII-XVIII section.

[0081] Figure 19 It represents Figure 4 Cross-sectional view of the XIX-XIX section.

[0082] Figure 20 It represents Figure 5 Cross-sectional view of the XX-XX section.

[0083] Figure 21 It represents Figure 5 Cross-sectional view of the XXI-XXI section.

[0084] Figure 22 It represents Figure 5 Cross-sectional view of the XXII-XXII section.

[0085] Figure 23 It represents Figure 5 Cross-sectional view of the XXIII-XXIII section.

[0086] Figure 24 It represents Figure 5 Cross-sectional view of the XXIV-XXIV section.

[0087] Figure 25 It represents Figure 6 Cross-sectional view of the XXV-XXV section.

[0088] Figure 26 It represents Figure 6 Cross-sectional view of the XXVI-XXVI section.

[0089] Figure 27 It represents Figure 6 Cross-sectional view of the XXVII-XXVII section.

[0090] Figure 28 It represents Figure 6 Cross-sectional view of the XXVIII-XXVIII section.

[0091] Figure 29 It represents Figure 6 Cross-sectional view of the XXIX-XXIX section.

[0092] Figure 30It is a plan view of the outer peripheral surface of the barrel of a writing instrument that expands and shows a modified example of the first embodiment, and an enlarged view that enlarges a part of the plan view.

[0093] Figure 31 It is a plan view of the outer peripheral surface of the barrel of a writing instrument that expands and shows the second embodiment, and an enlarged view that enlarges a part of the plan view.

[0094] Figure 32 It is a view that enlarges Figure 31 Part XXXII of, specifically, a plan view showing fibrous protrusions (axial protrusions).

[0095] Figure 33 It is a view showing Figure 32 A cross-sectional view of the XXXIII-XXXIII section of.

[0096] Figure 34 It is a view showing Figure 32 A cross-sectional view of the XXXIV-XXXIV section of.

[0097] Figure 35 It is a view showing Figure 32 A cross-sectional view of the XXXV-XXXV section of.

[0098] Figure 36 It is a view showing Figure 32 A cross-sectional view of the XXXVI-XXXVI section of.

[0099] Figure 37 It is a view showing Figure 32 A cross-sectional view of the XXXVII-XXXVII section of. Detailed implementation mode

[0100] <First embodiment>

[0101] Refer to Figures 1 to 29 The writing instrument 10 of the first embodiment of the present invention will be described. The writing instrument 10 of this embodiment is, for example, a ballpoint pen or the like, specifically, a click-type ballpoint pen or the like.

[0102] As Figure 1 shown, the writing instrument 10 has a substantially cylindrical shape centered on the central axis O. The writing instrument 10 includes a barrel 1 extending along the central axis O, a writing member 2 disposed inside the barrel 1, a grip portion 3 fitted to the outer peripheral surface of the barrel 1, a pen clip 4, a biasing member (not shown), a click mechanism (not shown), and a pressing portion 5. The barrel 1, the writing member 2, the grip portion 3, the biasing member, the click mechanism, and the pressing portion 5 are coaxially arranged with the central axis O as a common axis.

[0103] The definition of the directions used in this embodiment will be described.

[0104] In the present embodiment, the direction in which the central axis O of the writing instrument 10 extends, that is, the direction along the central axis O, is referred to as the axial direction. In the axial direction, the tip 21 of the writing member 2 that constitutes the writing instrument and the pressing portion 5 are arranged at different positions. In the axial direction, the direction from the pressing portion 5 toward the tip 21 is referred to as the front side, and the direction from the tip 21 toward the pressing portion 5 is referred to as the rear side. Therefore, the axial direction can also be described as the front-rear direction. In each figure, the axial direction (front-rear direction) corresponds to the Y-axis direction. The front side corresponds to the -Y side, and the rear side corresponds to the +Y side.

[0105] The direction orthogonal to the central axis O is referred to as the radial direction. In the radial direction, the direction approaching the central axis O is referred to as the inner radial side, and the direction away from the central axis O is referred to as the outer radial side. In each figure, the radial direction corresponds to the Z-axis direction. The inner radial side corresponds to the -Z side, and the outer radial side corresponds to the +Z side.

[0106] The direction of rotation around the central axis O is referred to as the circumferential direction. In each figure, the circumferential direction corresponds to the X-axis direction. In the present embodiment, when observing the writing instrument 10 from the rear side (+Y side), the circumferential side corresponding to the counterclockwise direction around the central axis O is the +X side, and the circumferential side corresponding to the clockwise direction around the central axis O is the -X side.

[0107] Each component of the writing instrument 10 will be described.

[0108] As Figure 1 shown, the shaft cylinder 1 is in a cylindrical shape centered on the central axis O and extends in the axial direction. The shaft cylinder 1 is made of a resin mainly composed of polycarbonate or the like, for example. The shaft cylinder 1 is constituted by combining a plurality of cylindrical members by screwing, fitting, bonding, etc., for example. Although not particularly shown, each constituent member of the shaft cylinder 1 is made by so-called injection molding, in which a molten resin material is injected between a pair of molds and a core and cured.

[0109] The shaft cylinder 1 has a part made of a colorless transparent member, for example. In addition, the shaft cylinder 1 may also have a part made of an opaque member such as black, for example. That is, the shaft cylinder 1 includes at least one of a transparent member and an opaque member. It should be noted that the transparent member may also be a transparent member to which a prescribed color is imparted. In the present embodiment, "transparent" includes the concept of "translucent". More specifically, when observing the writing instrument 10 from the outer radial side, the case where the writing member 2 accommodated inside the shaft cylinder 1 can be visually seen through the shaft cylinder 1 and is seen through is referred to as "transparent". In addition, the opaque member may also be an opaque member to which a prescribed color other than black is imparted.

[0110] The shaft cylinder 1 has a front shaft 1a and a rear shaft 1b disposed on the rear side of the front shaft 1a. The front shaft 1a and the rear shaft 1b are each cylindrical and are arranged side by side along the axial direction. The rear end portion of the front shaft 1a and the front end portion of the rear shaft 1b are detachably fixed by screwing or the like.

[0111] The front end portion of the front shaft 1a is in the shape of a tapered cylinder that tapers as it approaches the front side. In other words, the front end portion of the front shaft 1a can also be referred to as a tapered cylinder portion. The front shaft 1a has a front end opening 1c disposed in the tapered cylinder portion and opening to the front side. The rear shaft 1b has a rear end opening 1d disposed at the rear end portion of the rear shaft 1b and opening to the rear side.

[0112] In addition, the front shaft 1a has an external thread portion (not shown) disposed at the rear end portion in the axial direction of the front shaft 1a. This external thread portion protrudes rearward beyond a grip portion 3 described later. The rear shaft 1b has an internal thread portion (not shown) disposed at the front end portion in the axial direction of the rear shaft 1b. This internal thread portion is screwed onto the external thread portion of the front shaft 1a.

[0113] Figure 2 is a plan view showing the outer peripheral surface of the rear shaft 1b (shaft cylinder 1) in an unfolded manner and an enlarged view showing a part of this plan view. As Figure 2 shown, the rear shaft 1b, i.e., the shaft cylinder 1, has fibrous protrusions 6 and a parting line PL disposed on the outer peripheral surface thereof. Specifically, the fibrous protrusions 6 and the parting line PL are disposed on at least a part of the outer peripheral surface of the rear shaft 1b. It should be noted that in Figure 1 the illustrations of the fibrous protrusions 6 and the parting line PL are omitted. The detailed configuration of the fibrous protrusions 6 and the parting line PL will be described separately later.

[0114] The writing member 2 can also be referred to as a refill or a replacement part, etc. In Figure 1 the writing member 2 is detachably assembled inside the shaft cylinder 1. By disassembling the shaft cylinder 1 into a plurality of components (in this embodiment, the front shaft 1a and the rear shaft 1b), the writing member 2 can be removed from inside the shaft cylinder 1 for replacement.

[0115] As Figure 1 shown, the writing member 2 has a nib 21 and an ink storage cylinder (not shown) connected to the rear end portion of the nib 21. The nib 21 has a ball at the front end portion thereof and a seat for holding the ball.

[0116] In this embodiment, the writing instrument 10 is a click-type ballpoint pen. Therefore, the writing member 2 can move axially between a use position, where the nib 21 protrudes forward from the front end opening 1c of the shaft cylinder 1, and a storage position, where the entire writing member 2 including the nib 21 is stored inside the shaft cylinder 1.

[0117] Although not particularly illustrated, the ink storage cylinder is disposed inside the shaft cylinder 1. The ink storage cylinder is cylindrical with the central axis O as the center and extends in the axial direction. Inside the ink storage cylinder, for example, ink such as gel ink and grease are accommodated to suppress evaporation and backflow (flow to the rear side) of the ink is disposed at the rear side of the ink. The ink storage cylinder can also be referred to as an ink cartridge or the like.

[0118] The holding portion 3 is constituted by an elastic member such as an elastomer or rubber that can be elastically deformed, for example. However, it is not limited thereto, and the holding portion 3 can also be constituted by a resin member or the like other than the elastic member. The holding portion 3 is cylindrical with the central axis O as the center and extends in the axial direction. The holding portion 3 is fitted to the outer peripheral surface of the front shaft 1a. Specifically, the holding portion 3 is fitted to a portion of the outer peripheral surface of the front shaft 1a that is located between the front end portion (conical cylinder portion) and the rear end portion (external thread portion) in the axial direction.

[0119] The clip 4 is connected to the rear end portion in the axial direction of the shaft cylinder 1 and protrudes radially outward from the outer peripheral surface of the shaft cylinder 1. Specifically, the clip 4 is connected to the rear end portion of the outer peripheral surface of the rear shaft 1b and extends forward in the axial direction from this connection portion. The clip 4 is disposed opposite to the outer peripheral surface of the rear shaft 1b, that is, the outer peripheral surface of the shaft cylinder 1, from the radial outside. A part of the clip 4 may also be in contact with the outer peripheral surface of the shaft cylinder 1. The clip 4 may also be integrally formed with one of the plurality of constituent members of the rear shaft 1b by a single member. The clip 4 is made of a resin or metal that can be elastically deformed.

[0120] By using the clip 4, the user can hang the writing instrument 10 on a pocket or the like of clothes or the like for holding. In addition, by providing the clip 4, it is possible to prevent the writing instrument 10 from rolling unintentionally on a table or the like.

[0121] Although not particularly illustrated, the biasing member is, for example, a compression coil spring or the like. The biasing member is spiral with the central axis O as the center. The biasing member is disposed inside the shaft cylinder 1 and biases the writing member 2 toward the rear side. In the present embodiment, the biasing member is accommodated inside the front shaft 1a.

[0122] The pressing portion 5 is cylindrical with the central axis O as the center and extends in the axial direction. The pressing portion 5 is, for example, a capped cylindrical shape with the rear end portion closed. The pressing portion 5 is inserted into the rear end opening portion 1d of the shaft cylinder 1. At least a part (rear end portion) of the pressing portion 5 protrudes rearward from the rear end opening portion 1d.

[0123] Although not particularly illustrated, the pressing mechanism is provided inside the shaft cylinder 1. The pressing mechanism is configured such that by a user's operation of pressing the pressing portion 5 forward against the biasing force of the biasing member and releasing the pressing (pressing operation), the writing member 2 can be switched between the above-described use position and the storage position. Specifically, each time the user performs a pressing operation, the writing member 2 alternately moves axially to the use position and the storage position. As the pressing mechanism of the present embodiment, a structure of a pressing mechanism including, for example, a rotary cam, which is provided in a conventional ballpoint pen, can be adopted.

[0124] Next, Figures 2 to 29 the fibrous protrusions 6 and the parting line PL will be described in detail.

[0125] As Figure 2 shown, the fibrous protrusions 6 and the parting line PL are disposed on the outer peripheral surface of the rear shaft 1b in the shaft cylinder 1. The rear shaft 1b may be made of a transparent member or an opaque member.

[0126] Although not particularly illustrated, the fibrous protrusions 6 and the parting line PL may also be disposed on the outer peripheral surface of the front shaft 1a in the shaft cylinder 1. However, in this case, the fibrous protrusions 6 and the parting line PL are disposed on a portion other than the portion where the gripping portion 3 is fitted in the outer peripheral surface of the front shaft 1a (for example, a tapered cylinder portion or the like).

[0127] That is, the fibrous protrusions 6 and the parting line PL are disposed on a portion other than the portion of the outer peripheral surface of the shaft cylinder 1 covered by the gripping portion 3.

[0128] In the present embodiment, the fibrous protrusions 6 and the parting line PL are formed on the outer peripheral surface of the rear shaft 1b by transferring the shape of the inner surface of a pair of molds (not shown) used for injection molding the rear shaft 1b. Specifically, on the inner surface of the pair of molds used for injection molding the rear shaft 1b, precise concave engraving (laser engraving) (not shown) is performed by laser processing. The concave shape of this laser engraving is transferred as a convex shape (a shape obtained by inverting the above-described concave shape) on the outer peripheral surface of the rear shaft 1b during injection molding. Thus, precise convex fibrous protrusions 6 are formed on the outer peripheral surface of the shaft cylinder 1.

[0129] Therefore, the fibrous protrusions 6 project radially outward from the outer peripheral surface of the shaft cylinder 1. It should be noted that the "outer peripheral surface" specifically refers to a portion of the outer peripheral surface of the shaft cylinder 1 other than the portion where the fibrous protrusions 6 and the parting line PL are disposed. In the present embodiment, this portion may be separately referred to as a base surface or a reference surface, etc., from the fibrous protrusions 6 and the parting line PL. The base surface (reference surface) is disposed, for example, between adjacent fibrous protrusions 6 and between an adjacent fibrous protrusion 6 and the parting line PL.

[0130] A base surface is formed by transferring the shape of a non-laser processed portion, i.e., a non-laser processed part, of the inner surface of a pair of molds for injection molding the rear axle 1b to the outer peripheral surface of the rear axle 1b during injection molding. It should be noted that since the non-laser processed portion is transferred to the base surface formed on the outer peripheral surface of the rear axle 1b, it is a shiny surface.

[0131] Figures 2 to 6 The monochromatic images shown in the respective figures of to Figures 2 to 6 represent the laser intensity (laser output) during laser processing of the inner surface of the mold for molding the rear axle 1b by the shades of black and white. As shown in the monochromatic images of the respective figures, the laser intensity of the laser processed portion on the inner surface of the mold changes stepwise or gradually (in a gradient manner), thereby performing precise laser engraving (precision engraving) on the inner surface of the mold.

[0132] The shape of the laser processed portion of the inner surface of the mold is inverted and transferred as it is to the outer peripheral surface of the rear axle 1b. Therefore, Figures 2 to 6 the monochromatic images shown in the respective figures of Figures 2 to 6 to

[0133] can also be said to represent the protrusion amount of the fibrous protrusions 6 protruding radially outward from the outer peripheral surface (base surface) of the rear axle 1b by the shades of black and white. That is, the protrusion amount of the fibrous protrusions 6 changes stepwise or gradually (in a gradient manner) in each part of the fibrous protrusions 6.

[0133] More specifically, in the monochromatic images shown in the respective figures, the darker the shade of black and white (the part closer to 100% black), the larger the protrusion amount of the fibrous protrusions 6. In addition, the lighter the shade of black and white (the part closer to 100% white, in other words, the part closer to 0% black), the smaller the protrusion amount of the fibrous protrusions 6.

[0134] The maximum value (maximum protrusion size) of the protrusion amount of the fibrous protrusions 6 protruding radially outward from the outer peripheral surface (base surface) of the shaft cylinder 1 is, for example, 100 μm or less. In the present embodiment, the maximum protrusion size of the fibrous protrusions 6 is, for example, about 50 μm. More specifically, in Figure 2 the fibrous protrusions 6 shown in the monochromatic image of Figure 2 , the protrusion amount at the darkest part (100% black) is equivalent to about 50 μm (maximum protrusion amount), and the protrusion amount at the lightest part (0% black) is equivalent to about 0 μm.

[0135] As Figure 2 shown, a plurality of fibrous protrusions 6 are arranged side by side on the outer peripheral surface of the rear axle 1b (shaft cylinder 1). The plurality of fibrous protrusions 6 include axial protrusions 6A, 6B extending in the axial direction (Y-axis direction) and circumferential protrusions 6C, 6D extending in the circumferential direction (X-axis direction).

[0136] A plurality of axial protrusions 6A and 6B are provided. The plurality of axial protrusions 6A and 6B include a first axial protrusion 6A and a second axial protrusion 6B having a shape different from that of the first axial protrusion 6A. In addition, a plurality of circumferential protrusions 6C and 6D are provided. The plurality of circumferential protrusions 6C and 6D include a first circumferential protrusion 6C and a second circumferential protrusion 6D having a shape different from that of the first circumferential protrusion 6C.

[0137] That is, the plurality of fibrous protrusions 6 include a variety of axial protrusions 6A and 6B extending in the axial direction and having different shapes, and a variety of circumferential protrusions 6C and 6D extending in the circumferential direction and having different shapes.

[0138] The first axial protrusion 6A and the second axial protrusion 6B are alternately arranged side by side in the axial direction. A plurality of columns of the axial protrusions 6A and 6B arranged in the axial direction are arranged side by side in the circumferential direction. In a pair of adjacent columns of the axial protrusions 6A and 6B in the circumferential direction, the axial positions of one column of the axial protrusions 6A and 6B are offset from those of the other column of the axial protrusions 6A and 6B.

[0139] Although not particularly illustrated, at least one column of the axial protrusions 6A and 6B arranged side by side in the circumferential direction overlaps with the clip 4 when viewed from the radial direction. That is, the plurality of fibrous protrusions 6 include the axial protrusions 6A and 6B that overlap with the clip 4 when viewed from the radial direction and extend in the axial direction.

[0140] The first circumferential protrusion 6C and the second circumferential protrusion 6D are alternately arranged side by side in the axial direction. A plurality of columns of the circumferential protrusions 6C and 6D arranged in the axial direction are arranged side by side in the circumferential direction. In a pair of adjacent columns of the circumferential protrusions 6C and 6D in the circumferential direction, the axial positions of one column of the circumferential protrusions 6C and 6D are offset from those of the other column of the circumferential protrusions 6C and 6D.

[0141] In addition, the axial protrusions 6A and 6B and the circumferential protrusions 6C and 6D are alternately arranged in at least one of the axial direction and the circumferential direction. In the present embodiment, the axial protrusions 6A and 6B and the circumferential protrusions 6C and 6D are alternately arranged in the axial direction and alternately arranged in the circumferential direction.

[0142] As represented by the light and dark of black and white in the Figure 2 monochrome image, in the present embodiment, the amount of protrusion of the axial protrusions 6A and 6B toward the radially outer side (+Z side) is larger than the amount of protrusion of the circumferential protrusions 6C and 6D toward the radially outer side. That is, compared with the pattern along the circumferential direction presented by the circumferential protrusions 6C and 6D, the pattern along the axial direction presented by the axial protrusions 6A and 6B is a more emphasized design.

[0143] Here, the detailed configuration and the like common to each of the fibrous protrusions 6 (6A to 6D) will be described.

[0144] The fibrous protrusion 6 has a textured surface on its surface. The textured surface is a frosted glass-like (ground glass-like) or pear skin-like surface and has a surface roughness above a specified value. The textured surface can also be described as a matte (extinction) processed surface, for example. In the present embodiment, the textured surface is formed on the entire surface of the fibrous protrusion 6.

[0145] Specifically, by performing laser processing on the inner surface of the mold for forming the rear shaft 1b, from a microscopic viewpoint finer than the laser engraving design, the surface of the laser-processed portion of the inner surface of the mold is roughened to a surface roughness above a specified value. When the rear shaft 1b is injection-molded, the laser-processed portion of the inner surface of the mold is transferred to form the fibrous protrusion 6. Therefore, from a microscopic viewpoint, the surface of the fibrous protrusion 6 is roughened to a surface roughness above a specified value and thus becomes a textured surface.

[0146] When the outer peripheral surface of the shaft cylinder 1 is observed from the front (that is, from the radially outer side), the fibrous protrusions 6 extend in a specified direction. That is, when observed from the radially outer side, the dimension of the fibrous protrusion 6 in the specified direction is larger than the dimension in the width direction orthogonal to the specified direction. Therefore, in each fibrous protrusion 6 (6A to 6D), the specified direction can also be referred to as the long dimension direction, and the width direction can be referred to as the short dimension direction.

[0147] Specifically, among the various fibrous protrusions 6A to 6D, in the axial protrusions 6A and 6B, the specified direction corresponds to the Y-axis direction (axial direction), and the width direction corresponds to the X-axis direction (circumferential direction). In addition, in the circumferential protrusions 6C and 6D, the specified direction corresponds to the X-axis direction (circumferential direction), and the width direction corresponds to the Y-axis direction (axial direction).

[0148] In addition, the dimension of the fibrous protrusion 6 in the specified direction is, for example, 2 mm or less. In the present embodiment, the dimension of the fibrous protrusion 6 in the specified direction is 1.5 mm or less, specifically, about 1.1 mm to 1.2 mm.

[0149] The dimension of the fibrous protrusion 6 in the width direction is, for example, 1.5 mm or less. In the present embodiment, the dimension of the fibrous protrusion 6 in the width direction is 1 mm or less, specifically, about 0.5 mm to 0.6 mm.

[0150] As Figures 3 to 6 shown in the respective figures, in the present embodiment, the fibrous protrusions 6 (6A to 6D) have a face-symmetric shape with respect to an imaginary plane (symmetry plane), which is located at the center of the fibrous protrusion 6 in the specified direction (long dimension direction) and extends in a direction (plane direction) perpendicular to the specified direction.

[0151] In addition, Figure 3 and Figure 4The axial protrusions 6A and 6B shown have a face-symmetric shape with respect to an imaginary plane (symmetry plane), not shown, that is located at the center of the width direction (short dimension direction) of the fibrous protrusion 6 and extends in a direction (plane direction) perpendicular to the width direction.

[0152] In addition, Figure 5 and Figure 6 the circumferential protrusions 6C and 6D shown have a non-face-symmetric shape with respect to an imaginary plane that is located at the center of the width direction (short dimension direction) of the fibrous protrusion 6 and extends in a direction (plane direction) perpendicular to the width direction.

[0153] As Figures 3 to 6 shown by the light and dark of the monochromatic images in the respective figures, the protruding amounts of the respective fibrous protrusions 6 (6A to 6D) toward the radially outer side (+Z side) are different at respective positions in a specified direction (long dimension direction). In each of the fibrous protrusions 6 (6A to 6D), the protruding amount toward the radially outer side of the middle portion located between the both ends in the specified direction is larger than the protruding amounts toward the radially outer side of the both ends in the specified direction. It should be noted that by referring to Figure 7 it is possible to more intuitively understand the above configuration, where Figure 7 shows Figure 3 the fibrous protrusion 6 (first axial protrusion 6A) as a schematic perspective view.

[0154] Specifically, in each of the fibrous protrusions 6 (6A to 6D), the protruding amount toward the radially outer side increases as it approaches the central portion from the both ends in the specified direction, and the protruding amount becomes maximum at the central portion in the specified direction.

[0155] As Figures 3 to 7 shown, each of the fibrous protrusions 6 has: a plurality of rib portions 7 that extend in the specified direction when viewed from the radially outer side and are arranged side by side in the width direction; and a step portion 8 that extends in the specified direction and is arranged between the rib portions 7 adjacent in the width direction or at the width-direction end of the rib portion 7.

[0156] In the present embodiment, the plurality of rib portions 7 included in the fibrous protrusion 6 are arranged adjacent to each other in the width direction. Specifically, for the rib portions 7 adjacent to each other in the width direction, the width-direction ends facing each other are connected to each other. In addition, a plurality of step portions 8 are provided in the fibrous protrusion 6. Each step portion 8 is arranged on the side surface of each rib portion 7 facing the width direction.

[0157] At least one of the plurality of rib portions 7 has an increasing protruding amount toward the radially outer side as it approaches the central portion from the both ends in the specified direction (long dimension direction). In the present embodiment, all of the rib portions 7 included in each of the fibrous protrusions 6 (6A to 6D) have an increasing protruding amount toward the radially outer side as they approach the central portion from the both ends in the specified direction.

[0158] It should be noted that although not particularly illustrated, among the plurality of ribs 7, there may also be ribs in which the amount of protrusion is constant throughout the entire length in a specified direction. In addition, among the plurality of ribs 7, there may also be ribs in which the amount of protrusion decreases as the center portion is approached from both end portions in the specified direction.

[0159] The plurality of ribs 7 include outer ribs 7A disposed at the outer ends in the width direction of the fibrous protrusions 6 and inner ribs 7B disposed closer to the inner side in the width direction than the outer ribs 7A.

[0160] A pair of outer ribs 7A are provided at both end portions on the outer side in the width direction of the fibrous protrusions 6. A plurality of inner ribs 7B are arranged side by side in the width direction. The shapes of adjacent inner ribs 7B in the width direction are different from each other. The amounts of protrusion of the plurality of inner ribs 7B toward the radially outer side are different from each other.

[0161] The inner ribs 7B have portions with a larger amount of protrusion toward the radially outer side than the outer ribs 7A. The maximum value (maximum protrusion dimension) of the amount of protrusion of the inner ribs 7B toward the radially outer side is larger than the maximum value of the amount of protrusion of the outer ribs 7A toward the radially outer side.

[0162] Therefore, in each of the fibrous protrusions 6 (6A to 6D), the amount of protrusion of the middle portion (inner ribs 7B) located between both end portions in the width direction (short dimension direction) toward the radially outer side (+Z side) is larger than the amount of protrusion of both end portions (outer ribs 7A) in the width direction.

[0163] The plurality of inner ribs 7B include first inner ribs 7B1 and second inner ribs 7B2. Among the plurality of inner ribs 7B, the amount of protrusion of the first inner ribs 7B1 toward the radially outer side at the central portion in the specified direction (long dimension direction) is the largest. The amount of protrusion of the second inner ribs 7B2 toward the radially outer side at the central portion in the specified direction is smaller than that of the first inner ribs 7B1.

[0164] Here, Figures 8 to 13 Each of the cross-sectional views shown represents Figure 3 the VIII-VIII cross-section to the XIII-XIII cross-section of the first axial protrusion 6A. As Figure 3 , Figure 7 and Figures 8 to 13 shown, the plurality of inner ribs 7B included in the first axial protrusion 6A include first inner ribs 7B1, second inner ribs 7B2, and third inner ribs 7B3. The amount of protrusion of the third inner ribs 7B3 toward the radially outer side at the central portion in the specified direction is smaller than that of the first inner ribs 7B1 and larger than that of the second inner ribs 7B2.

[0165] In the first axial protrusion 6A, the first inner rib portion 7B1 is disposed at the central portion in the width direction among the plurality of inner rib portions 7B. Further, the second inner rib portion 7B2 is disposed at the end portion in the width direction among the plurality of inner rib portions 7B. Further, the third inner rib portion 7B3 is disposed between the first inner rib portion 7B1 and the second inner rib portion 7B2 in the width direction.

[0166] The first axial protrusion 6A has one first inner rib portion 7B1, two second inner rib portions 7B2, and two third inner rib portions 7B3. That is, the first axial protrusion 6A has a total of five inner rib portions 7B.

[0167] As Figure 11 shown, at the end portion in the specified direction of the first axial protrusion 6A, the protrusion amount of the second inner rib portion 7B2 among the plurality of rib portions 7 toward the radially outer side (+Z side) is the largest. That is, the protrusion amount of the second inner rib portion 7B2 toward the radially outer side at the end portion in the specified direction is larger than the protrusion amounts of the end portions in the respective specified directions of the first inner rib portion 7B1, the third inner rib portion 7B3, and the outer rib portion 7A toward the radially outer side.

[0168] Further, as Figure 12 shown, at a specified portion between the end portion and the central portion in the specified direction of the first axial protrusion 6A, the protrusion amount of the third inner rib portion 7B3 among the plurality of rib portions 7 toward the radially outer side is the largest.

[0169] Further, as Figure 13 shown, at the central portion in the specified direction of the first axial protrusion 6A, the protrusion amount of the first inner rib portion 7B1 among the plurality of rib portions 7 toward the radially outer side is the largest.

[0170] The dimensions in the width direction of the plurality of rib portions 7 (7A, 7B) provided in the first axial protrusion 6A are the same as each other.

[0171] Further, Figures 14 to 19 The respective cross-sectional views shown represent Figure 4 the cross sections XIV-XIV to XIX-XIX of the second axial protrusion 6B. As Figure 4 and Figures 14 to 19 shown, the plurality of inner rib portions 7B included in the second axial protrusion 6B include a first inner rib portion 7B1, a second inner rib portion 7B2, and a third inner rib portion 7B3. The protrusion amount of the third inner rib portion 7B3 toward the radially outer side at the central portion in the specified direction is smaller than that of the first inner rib portion 7B1 and larger than that of the second inner rib portion 7B2.

[0172] In the second axial projection 6B, the third inner rib 7B3 is disposed at the central portion in the width direction among the plurality of inner ribs 7B. Further, the second inner rib 7B2 is disposed at the end portion in the width direction among the plurality of inner ribs 7B. Further, the first inner rib 7B1 is disposed between the third inner rib 7B3 and the second inner rib 7B2 in the width direction.

[0173] The second axial projection 6B has one third inner rib 7B3, two second inner ribs 7B2, and two first inner ribs 7B1. That is, the second axial projection 6B has a total of five inner ribs 7B.

[0174] As Figure 17 shown, at the end portion in the specified direction of the second axial projection 6B, the protruding amount of the second inner rib 7B2 among the plurality of ribs 7 toward the radially outer side (+Z side) is the largest. That is, the protruding amount of the second inner rib 7B2 toward the radially outer side at the end portion in the specified direction is larger than that of the first inner rib 7B1, the third inner rib 7B3, and the outer rib 7A at the end portion in each specified direction.

[0175] Further, as Figure 18 shown, at a specified portion between the end portion and the central portion in the specified direction of the second axial projection 6B, the protruding amount of the third inner rib 7B3 among the plurality of ribs 7 toward the radially outer side is the largest.

[0176] Further, as Figure 19 shown, at the central portion in the specified direction of the second axial projection 6B, the protruding amount of the first inner rib 7B1 among the plurality of ribs 7 toward the radially outer side is the largest.

[0177] The dimensions in the width direction of the plurality of ribs 7 (7A, 7B) provided in the second axial projection 6B are the same as each other.

[0178] Further, Figures 20 to 24 the cross-sectional views shown represent Figure 5 the XX-XX cross-section to the XXIV-XXIV cross-section of the first circumferential projection 6C. As Figure 5 and Figures 20 to 24 shown, the plurality of inner ribs 7B included in the first circumferential projection 6C include the first inner rib 7B1 and the second inner rib 7B2.

[0179] The first circumferential projection 6C has two first inner ribs 7B1 and two second inner ribs 7B2. That is, the first circumferential projection 6C has a total of four inner ribs 7B.

[0180] In the first circumferential projection 6C, the first inner rib 7B1 and the second inner rib 7B2 (the four inner ribs 7B) are alternately arranged side by side in the width direction toward the -Y side (front side) in the order of the first inner rib 7B1, the second inner rib 7B2, the first inner rib 7B1, and the second inner rib 7B2.

[0181] In addition, the widths of the multiple (two) first inner ribs 7B1 of the first circumferential projection 6C are different from each other. In addition, the widths of the multiple (two) second inner ribs 7B2 of the first circumferential projection 6C are different from each other.

[0182] As Figure 22 shown, at the end of the first circumferential projection 6C in a specified direction, the protruding amounts of the multiple ribs 7 toward the radially outer side (+Z side) are the same.

[0183] In addition, as Figure 23 shown, at a specified portion between the end and the central portion of the first circumferential projection 6C in a specified direction, the protruding amount of the inner rib 7B toward the radially outer side is larger than that of the outer rib 7A toward the radially outer side. In addition, in Figure 23 , the protruding amounts of the first inner rib 7B1 and the second inner rib 7B2 toward the radially outer side are the same.

[0184] In addition, as Figure 24 shown, at the central portion of the first circumferential projection 6C in a specified direction, the protruding amount of the first inner rib 7B1 among the multiple ribs 7 toward the radially outer side is the largest.

[0185] In addition, Figures 25 to 29 The cross-sectional views shown represent the XXV-XXV cross-section to the XXIX-XXIX cross-section of the second circumferential projection 6D of Figure 6 . As Figure 6 and Figures 25 to 29 shown, the multiple inner ribs 7B of the second circumferential projection 6D include the first inner rib 7B1 and the second inner rib 7B2.

[0186] The second circumferential projection 6D has two first inner ribs 7B1 and two second inner ribs 7B2. That is, the second circumferential projection 6D has a total of four inner ribs 7B.

[0187] In the second circumferential projection 6D, the first inner rib 7B1 and the second inner rib 7B2 (the four inner ribs 7B) are alternately arranged side by side in the width direction toward the -Y side (front side) in the order of the second inner rib 7B2, the first inner rib 7B1, the second inner rib 7B2, and the first inner rib 7B1.

[0188] In addition, the widths of the multiple (two) first inner ribs 7B1 of the second circumferential protrusion 6D are different from each other. In addition, the widths of the multiple (two) second inner ribs 7B2 of the second circumferential protrusion 6D are different from each other.

[0189] As Figure 27 shown, at the end of the second circumferential protrusion 6D in a specified direction, the protruding amounts of the multiple ribs 7 toward the outer side in each radial direction (+Z side) are the same.

[0190] In addition, as Figure 28 shown, at a specified portion between the end and the central portion of the second circumferential protrusion 6D in a specified direction, the protruding amount of the inner rib 7B toward the outer side in the radial direction is larger than that of the outer rib 7A toward the outer side in the radial direction. In addition, in Figure 28 it, the protruding amounts of the first inner rib 7B1 and the second inner rib 7B2 toward the outer side in the radial direction are the same as each other.

[0191] In addition, as Figure 29 shown, at the central portion of the second circumferential protrusion 6D in a specified direction, the protruding amount of the first inner rib 7B1 among the multiple ribs 7 toward the outer side in the radial direction is the largest.

[0192] As Figures 3 to 7 and the like shown, in each fibrous protrusion 6 (6A to 6D), the multiple stepped portions 8 include: an inner stepped portion 8A, disposed between the ribs 7 adjacent in the width direction and extending in a specified direction; and an outer stepped portion 8B, disposed at the end of the fibrous protrusion 6 in the width direction and extending in a specified direction.

[0193] The inner stepped portion 8A is formed according to the difference in the protruding amounts of the ribs 7 adjacent to each other in the width direction. In addition, the outer stepped portion 8B is formed on the side surface of the outer rib 7A facing the outer side in the width direction.

[0194] In addition, as Figure 7 shown, the multiple stepped portions 8 include at least one of a stepped portion whose radial (Z-axis direction) dimension changes as it faces a specified direction and a stepped portion whose radial dimension is constant throughout the entire length in the specified direction.

[0195] As Figure 2 shown, the parting line PL is disposed on the outer peripheral surface of the rear shaft 1b (shaft cylinder 1) and extends in the axial direction. Figure 2 The symbol C shown represents the circumferential center line C of the parting line PL. The circumferential dimension of the parting line PL is, for example, 1 mm or less. In the present embodiment, the circumferential dimension of the parting line PL is 0.5 mm or less, specifically, about 0.3 mm to 0.4 mm.

[0196] A plurality of parting lines PL are provided at circumferentially spaced intervals on the outer circumferential surface of the rear shaft 1b. In the present embodiment, a pair of parting lines PL are provided at equal intervals in the circumferential direction. That is, the pair of parting lines PL are arranged at positions that are rotationally symmetric by 180° with respect to each other about the central axis O of the shaft cylinder 1.

[0197] Each parting line PL is formed along the opposing surface (split surface) of a pair of molds (not shown) for injection molding the rear shaft 1b. Specifically, the parting line PL is formed by transferring the shape of a non-laser processed portion that is arranged at the circumferential end and extends in the axial direction on the inner surface of the mold for molding the rear shaft 1b during injection molding to the outer circumferential surface of the rear shaft 1b.

[0198] In the present embodiment, since the non-laser processed portion is transferred, the parting line PL formed on the outer circumferential surface of the rear shaft 1b is a shiny glossy surface.

[0199] In the writing instrument 10 of the present embodiment described above, a plurality of fibrous protrusions 6 are provided on the outer circumferential surface of the shaft cylinder 1. Each fibrous protrusion 6 has a plurality of rib portions 7 extending in a predetermined direction and step portions 8 disposed between adjacent rib portions 7 in the width direction or at the width direction ends of the rib portions 7. By adopting such a plurality of fibrous protrusions 6 configured in this way, it is possible to give users and the like the feeling that the outer circumferential surface of the shaft cylinder 1 is made of a fabric, cloth, or a mat woven from rush grass or the like (hereinafter, abbreviated as fabric or the like) woven with actual yarns.

[0200] Specifically, through the plurality of rib portions 7 and the step portions 8, it is possible to approximate the shadow of the fibrous protrusion 6 to the shadow of yarns, rush grass, or the like that are elements of a fabric or the like. Therefore, it is possible to give users and the like of the writing instrument 10 a visual feeling that the outer circumferential surface of the shaft cylinder 1 is made of a fabric or the like.

[0201] In addition, when users and the like of the writing instrument 10 touch the fibrous protrusion 6 with their fingertips or the like, through the plurality of rib portions 7 and the step portions 8, it is possible to give a tactile feeling similar to that when touching the surface of an actual fabric or the like. Specifically, for example, a directional tactile sensation can be obtained as if the fibers on the surface of yarns, rush grass, or the like extend in a predetermined direction.

[0202] In addition, although not particularly shown, the outer circumferential surface of the shaft cylinder 1 contacts the "interdigital region" between the base of the index finger and the base of the thumb in the user's hand when using the writing instrument 10. In this writing instrument 10, by providing the fibrous protrusions 6, it is also possible to improve the tactile sensation of the shaft cylinder 1 at the interdigital region.

[0203] With the above, according to this embodiment, it is possible to give the outer peripheral surface of the shaft tube 1 a feeling as if it is made of an actual fabric or the like, with a good appearance and improved design, and a good touch and improved usability.

[0204] In addition, in this embodiment, in the fibrous protrusion 6, the amount of protrusion toward the radially outer side of the middle portion located between the two end portions in a specified direction is larger than that of the two end portions.

[0205] In addition, in the fibrous protrusion 6, the amount of protrusion toward the radially outer side of the middle portion located between the two end portions in the width direction is larger than that of the two end portions.

[0206] In this case, the shape of the fibrous protrusion 6 can be made more similar to the shape of the exposed portions of the yarns, rushes, etc. that make up an actual fabric or the like. It is possible to more stably give the outer peripheral surface of the shaft tube 1 a visual and tactile feeling as if it is made of an actual fabric or the like. The effects of improving the design and usability become more obvious.

[0207] In addition, in this embodiment, the plurality of rib portions 7 of the fibrous protrusion 6 include an outer rib portion 7A and an inner rib portion 7B, and the inner rib portion 7B has a portion with a larger amount of protrusion toward the radially outer side than the outer rib portion 7A.

[0208] In this case, in the fibrous protrusion 6, the inner rib portion 7B located on the inner side in the width direction protrudes significantly more toward the radially outer side than the outer rib portion 7A located at the outer end portion in the width direction. Thereby, the shape of the fibrous protrusion 6 can be made more similar to the shape of the exposed portions of the yarns, rushes, etc. that make up an actual fabric or the like. Therefore, the above-described effects become more obvious.

[0209] In addition, in this embodiment, the fibrous protrusion 6 has a plurality of inner rib portions 7B arranged side by side in the width direction, and the amount of protrusion (i.e., the height dimension) of each inner rib portion 7B toward the radially outer side is different from each other. Thereby, the shape of the fibrous protrusion 6 can be made more similar to the shape of the exposed portions of the yarns, rushes, etc. that make up an actual fabric or the like. Therefore, the above-described effects become more obvious.

[0210] In addition, in this embodiment, the plurality of inner rib portions 7B include: a first inner rib portion 7B1 having the largest amount of protrusion toward the radially outer side at the central portion in a specified direction; and a second inner rib portion 7B2 having a smaller amount of protrusion toward the radially outer side at the central portion in the specified direction than the first inner rib portion 7B1. In addition, the amount of protrusion of the second inner rib portion 7B2 toward the radially outer side at the end portion in the specified direction is larger than that of the first inner rib portion 7B1 at the end portion in the specified direction.

[0211] In this case, the inclinations and shapes of the first inner rib 7B1 and the second inner rib 7B2 among the plurality of inner ribs 7B of the fibrous protrusion 6 are different from each other. Thereby, the shape of the fibrous protrusion 6 can be made more similar to the shape of the yarns constituting an actual fabric or the like, or the exposed portions of the rush or the like. Therefore, the above-described effects become more obvious.

[0212] In addition, in the present embodiment, the plurality of fibrous protrusions 6 include axial protrusions 6A and 6B extending in the axial direction and circumferential protrusions 6C and 6D extending in the circumferential direction, and the axial protrusions 6A and 6B and the circumferential protrusions 6C and 6D are alternately arranged in at least one of the axial direction and the circumferential direction.

[0213] In this case, for example, the axial protrusions 6A and 6B function as warp yarns, and the circumferential protrusions 6C and 6D function as weft yarns, and a visual and tactile feeling as if they are alternately interwoven can be given to the shaft cylinder 1. A feeling as if the outer peripheral surface of the shaft cylinder 1 is formed of an actual fabric or the like can be given more effectively.

[0214] In addition, in the present embodiment, the amount of protrusion of the axial protrusions 6A and 6B toward the radially outer side is larger than that of the circumferential protrusions 6C and 6D.

[0215] In this case, in the outer peripheral surface of the shaft cylinder 1, the warp yarns (axial protrusions 6A and 6B) can be emphasized more visually and tactilely than the weft yarns (circumferential protrusions 6C and 6D). Therefore, the degree of freedom in design can be further improved and the touch can be made better.

[0216] In addition, in the present embodiment, the plurality of fibrous protrusions 6 include a plurality of axial protrusions 6A and 6B having different shapes from each other and a plurality of circumferential protrusions 6C and 6D having different shapes from each other.

[0217] In this case, a visual and tactile feeling as if the outer peripheral surface of the shaft cylinder 1 is formed of an actual fabric or the like can be given more effectively.

[0218] In addition, in the present embodiment, the fibrous protrusion 6 has a textured surface on its surface.

[0219] As described above, if the surface of the fibrous protrusion 6 has a textured surface, a finer, matte-like shadow can be given to the fibrous protrusion 6, or a smooth and comfortable touch can be given. Therefore, the designability can be further improved and the usability can be further improved.

[0220] In addition, in the present embodiment, the plurality of fibrous protrusions 6 include axial protrusions 6A and 6B that overlap the clip 4 when viewed from the radial direction and extend in the axial direction.

[0221] In this case, when the writing implement 10 is hung on a pocket of a user's clothes or the like by the pen clip 4 to be held or removed from the pocket or the like, the cloth of the pocket or the like easily slides between the pen clip 4 and the axial projections 6A, 6B, and the cloth is stably clamped. The writing implement 10 is easy to hang on a pocket or the like, and is also easy to remove, so the usability is good.

[0222] Furthermore, in the present embodiment, the fibrous protrusions 6 are arranged on the outer peripheral surface of the barrel 1 except for the portion covered by the gripping portion 3 .

[0223] In this case, the grip portion 3 can provide an anti-slip function when writing or the like, and the fibrous protrusions 6 will not be blocked by the grip portion 3. Therefore, the above-mentioned effects can be obtained more stably.

[0224] Here, refer to Figure 30 A modification of the first embodiment will be described. It should be noted that in the drawings of the modification, the same reference numerals are given to the same components as those of the above-described embodiment, and the following mainly describes the differences.

[0225] Figure 30 1 is a plan view showing the outer peripheral surface of the shaft cylinder 1 of the writing instrument 10 according to the modified example of the first embodiment, and an enlarged view showing a part of the plan view by enlarging the part. Figure 30 As shown, in this modification, at least one of the plurality of circumferential protrusions 6C, 6D is located on the parting line PL. In the example shown in the figure, at least the first circumferential protrusion 6C of the plurality of circumferential protrusions 6C, 6D is arranged to straddle the parting line PL in the circumferential direction (X-axis direction) and extends to intersect the parting line PL. In addition, a plurality of circumferential protrusions 6C, 6D located on the parting line PL are arranged side by side in the axial direction (Y-axis direction).

[0226] In addition, the parting line PL has a textured surface 9 extending in the axial direction. The textured surface 9 is a frosted glass-like (ground glass-like) or pear-skin-like surface having a surface roughness greater than a specified value. The textured surface 9 can also be, for example, a matte (dull) processed surface. The textured surface 9 is formed by transferring the laser processed portion of the inner surface of the mold when the rear axle 1b is injection molded. In the example shown in the figure, a plurality of textured surfaces 9 are arranged side by side in the axial direction.

[0227] The circumferential protrusions 6C and 6D and the textured surfaces 9 that intersect the parting line PL are arranged alternately in the axial direction.

[0228] Unlike the configuration of the above-described modification, for example, when the axially extending fibrous protrusions 6 (axial protrusions 6A and 6B) are disposed on the parting line PL, when the pair of molds are separated from each other after injection molding, the axial protrusions 6A and 6B on the parting line PL will rub against the molds, and sometimes tearing or burrs may occur.

[0229] On the other hand, as in the configuration of the above-described modification, when the circumferentially extending circumferential protrusions 6C and 6D are located on the parting line PL, since the pair of molds are separated from each other in the direction along which the circumferential protrusions 6C and 6D extend, it is possible to suppress the above-described defects such as tearing and burrs. Therefore, even if a parting line PL necessary for manufacturing is provided on the outer peripheral surface of the shaft tube 1, it is possible to suppress the pattern of the fabric or the like from being interrupted or becoming unnatural on the parting line PL, and the designability can be further improved.

[0230] In addition, since the parting line PL has a textured surface, even if a parting line PL necessary for manufacturing is provided on the outer peripheral surface of the shaft tube 1, the parting line PL can be made inconspicuous. Therefore, the designability can be further improved.

[0231] <Second Embodiment>

[0232] Next, with reference to Figure 1 and Figures 31 to 37 the writing instrument 20 of the second embodiment of the present invention will be described. It should be noted that in the present embodiment, for the same configurations as those in the foregoing embodiments, the same names, reference numerals, etc. may be used and their descriptions may be omitted. In addition, regarding the definition of directions, unless otherwise specified, it is the same as in the foregoing embodiments.

[0233] Figure 31 are a top view showing the outer peripheral surface of the shaft tube 1 of the writing instrument 20 of the second embodiment in an unfolded manner and an enlarged view showing a part of the top view enlarged. As Figure 31 shown, the writing instrument 20 of the present embodiment is different from the writing instrument 10 described in the foregoing embodiment in terms of the shape, arrangement, etc. of the fibrous protrusions 6.

[0234] Figure 31 and Figure 32 The monochromatic images shown in the respective figures represent the laser intensity (laser output) when laser processing is performed on the inner surface of the mold for forming the rear shaft 1b by the light and dark of black and white. In addition, Figure 31 and Figure 32 The monochromatic images shown in the respective figures represent the amount of protrusion of the fibrous protrusions 6 protruding radially outward from the outer peripheral surface (base surface) of the rear shaft 1b by the light and dark of black and white.

[0235] As Figure 31As shown, in the present embodiment, the plurality of fibrous protrusions 6 provided on the outer peripheral surface of the rear shaft 1b include a plurality of axial protrusions 6E extending in the axial direction. A plurality of columns of the axial protrusions 6E arranged at intervals in the axial direction are arranged side by side in the circumferential direction. In a pair of columns of the axial protrusions 6E adjacent in the circumferential direction, the axial positions of one column of the axial protrusions 6E and the other column of the axial protrusions 6E are offset from each other.

[0236] In addition, in the present embodiment, it can also be said that the plurality of axial protrusions 6E form an inclined column that extends in the axial direction as it faces the circumferential direction.

[0237] Specifically, in Figure 31 the example shown, the plurality of axial protrusions 6E arranged on the circumferential side (+X side) of the parting line PL constitute an inclined column that extends toward the front side (-Y side) as it faces the circumferential side. A plurality of columns of the inclined column are arranged side by side in the axial direction.

[0238] In addition, the plurality of axial protrusions 6E arranged on the other circumferential side (-X side) of the parting line PL constitute an inclined column that extends toward the front side (-Y side) as it faces the other circumferential side. A plurality of columns of the inclined column are arranged side by side in the axial direction.

[0239] As Figure 32 shown, in the present embodiment, the fibrous protrusion 6 (axial protrusion 6E) also has: a plurality of rib portions 7 that extend in a specified direction (Y-axis direction) when viewed from the radially outer side (+Z side) and are arranged side by side in the width direction (X-axis direction); and a step portion 8 that is arranged between the rib portions 7 adjacent in the width direction or at the width-direction end of the rib portion 7 and extends in the specified direction.

[0240] The plurality of rib portions 7 include a pair of outer rib portions 7A arranged at both ends on the outer side in the width direction of the fibrous protrusion 6 (6E) and an inner rib portion 7B arranged on the inner side in the width direction relative to the outer rib portions 7A. That is, the axial protrusion 6E has a total of three rib portions 7.

[0241] Figures 33 to 37 Each of the cross-sectional views shown represents Figure 32 the XXXIII-XXXIII cross-section to XXXVII-XXXVII cross-section of the axial protrusion 6E of Figure 35 As shown, at the end in the specified direction of the axial protrusion 6E, the protruding amounts of the plurality of rib portions 7 toward the respective radially outer sides (+Z side) are the same.

[0242] In addition, as Figure 36As shown, at a specified portion between the end portion in a specified direction and the central portion of the axial projection 6E, the amount of protrusion of the inner rib portion 7B toward the radially outer side is larger than the amount of protrusion of the outer rib portion 7A toward the radially outer side. That is, in the present embodiment, the inner rib portion 7B also has a portion with a larger amount of protrusion toward the radially outer side than the outer rib portion 7A.

[0243] In addition, as Figure 37 shown, at the central portion in the specified direction of the axial projection 6E, the amounts of protrusion of the plurality of rib portions 7 toward the respective radially outer sides are the same.

[0244] In the writing instrument 20 of the present embodiment described above, the same operational effects as those of the foregoing embodiments can also be obtained.

[0245] It should be noted that the present invention is not limited to the foregoing embodiments. For example, as described below, configuration changes and the like can be made without departing from the gist of the present invention.

[0246] In the foregoing first embodiment and second embodiment, examples were given in which the fibrous projections 6 (6A to 6E) extend in a specified direction when viewed from the radially outer side, but the present invention is not limited thereto. Specifically, in the present invention, it is sufficient that the rib portion 7 and the stepped portion 8 included in the fibrous projection 6 extend in a specified direction, respectively. Therefore, although not particularly illustrated, when viewed from the radially outer side, the dimension in the specified direction and the dimension in the width direction of the fibrous projection 6 may be the same. Alternatively, when viewed from the radially outer side, the dimension in the width direction of the fibrous projection 6 may be larger than the dimension in the specified direction.

[0247] In addition, in the foregoing first embodiment and second embodiment, a click-type ballpoint pen was given as an example of the writing instruments 10 and 20, but the present invention is not limited thereto. The writing instruments 10 and 20 may also be ballpoint pens other than click-type ballpoint pens, or pens other than ballpoint pens.

[0248] The present invention can combine the respective configurations described in the foregoing embodiments and modification examples and the like without departing from the gist of the present invention. In addition, addition, omission, replacement, and other changes of the configuration can be made. In addition, the present invention is not limited by the foregoing embodiments and the like, but is only limited by the claims.

[0249] Industrial Applicability

[0250] According to the writing instrument of the present invention, a feeling as if the outer peripheral surface of the barrel is made of a fabric or the like can be imparted, the appearance is good, the designability can be improved, and the touch feeling is good and the usability is improved. Therefore, it has industrial applicability.

[0251] Explanation of Reference Numerals

[0252] 1: shaft cylinder; 2: writing member; 3: gripping portion; 4: pen clip; 6(6A - 6E): fibrous protrusion; 6A, 6B, 6E: axial protrusion; 6C, 6D: circumferential protrusion; 7: rib portion; 7A: outer rib portion; 7B: inner rib portion; 8: stepped portion; 9: textured surface of parting line; 10, 20: writing instrument; 7B1: first inner rib portion; 7B2: second inner rib portion; O: central axis; PL: parting line.

Claims

1. A writing instrument, comprising: A barrel that extends axially along a central axis; and A writing member disposed inside the barrel, The barrel has fibrous protrusions that project radially outward from the outer peripheral surface of the barrel, A plurality of the fibrous protrusions are arranged side by side on the outer peripheral surface, Each of the fibrous protrusions has: A plurality of rib portions that extend in a specified direction when viewed from the radially outer side and are arranged side by side in a width direction orthogonal to the specified direction; and A stepped portion that extends in the specified direction and is disposed between the rib portions adjacent in the width direction or at the width-direction end of the rib portion.

2. The writing instrument according to claim 1, Wherein, In the fibrous protrusion, the amount of protrusion radially outward of the middle portion located between the two end portions in the specified direction is larger than that of the two end portions.

3. The writing instrument according to claim 1 or 2, Wherein, In the fibrous protrusion, the amount of protrusion radially outward of the middle portion located between the two end portions in the width direction is larger than that of the two end portions.

4. The writing instrument according to claim 1 or 2, Wherein, The plurality of rib portions include: Outer rib portions disposed at the outer ends in the width direction of the fibrous protrusion; and Inner rib portions disposed closer to the inner side in the width direction than the outer rib portions, The inner rib portions have portions with a larger amount of protrusion radially outward than the outer rib portions.

5. The writing instrument according to claim 4, Wherein, A plurality of the inner rib portions are arranged side by side in the width direction.

6. The writing instrument according to claim 5, Wherein, The amounts of protrusion radially outward of the plurality of inner rib portions are different from each other.

7. The writing instrument according to claim 5, Wherein, The plurality of inner rib portions include: A first inner rib portion, among the plurality of inner rib portions, the amount of protrusion radially outward at the central portion in the specified direction of the first inner rib portion is the largest; and A second inner rib portion, the amount of protrusion radially outward at the central portion in the specified direction of which is smaller than that of the first inner rib portion, The amount of protrusion radially outward at the end portion in the specified direction of the second inner rib portion is larger than that of the first inner rib portion at the end portion in the specified direction.

8. The writing instrument according to claim 1 or 2, Wherein, The plurality of fibrous protrusions include: Axial protrusions that extend axially; and Circumferential protrusions that extend circumferentially, The axial protrusions and the circumferential protrusions are alternately arranged in at least one of the axial direction and the circumferential direction.

9. The writing instrument according to claim 1 or 2, Wherein, The plurality of fibrous protrusions include: Axial protrusions that extend axially; and Circumferential protrusions that extend circumferentially, The amount of protrusion radially outward of the axial protrusions is larger than that of the circumferential protrusions.

10. The writing instrument according to claim 1 or 2, Wherein, The plurality of fibrous protrusions include: Multiple types of axial protrusions that extend axially and have different shapes; and Multiple types of circumferential protrusions that extend circumferentially and have different shapes.

11. The writing instrument according to claim 1 or 2, wherein, the fibrous protrusions have a textured surface on their surfaces.

12. The writing instrument according to claim 1 or 2, wherein, the barrel has a parting line disposed on the outer peripheral surface of the barrel and extending in the axial direction, the plurality of fibrous protrusions include a plurality of circumferential protrusions extending in the circumferential direction, at least one of the plurality of circumferential protrusions is located on the parting line.

13. The writing instrument according to claim 12, wherein, the parting line has a textured surface extending in the axial direction.

14. The writing instrument according to claim 1 or 2, further comprising: a clip extending in the axial direction and disposed opposite to the barrel from the radially outer side, the plurality of fibrous protrusions include axial protrusions that overlap the clip when viewed radially and extend in the axial direction.

15. The writing instrument according to claim 1 or 2, further comprising: a grip portion fitted to the outer peripheral surface of the barrel, the fibrous protrusions are disposed on a portion of the outer peripheral surface of the barrel other than the portion covered by the grip portion.

Images