Writing instrument

Abstract

To provide a writing instrument capable of preventing leakage of a coating liquid while more accurately controlling the amount of the coating liquid supplied to a tip portion. The writing instrument has: a tip portion that applies the coating liquid; a coating liquid storage portion that stores the coating liquid; a cylindrical barrel portion that covers the coating liquid storage portion and is fixed to the tip portion; a valve mechanism provided at a front end portion of the coating liquid storage portion; an operation member fixed to the tip portion, capable of opening the valve mechanism and allowing the coating liquid to flow from the coating liquid storage portion to the tip portion side through the valve mechanism; and a cylindrical elastic member that is axially stretchable and connects the valve mechanism and the operation member and defines a flow path of the coating liquid between the valve mechanism and the operation member; the coating liquid storage portion is axially movable relative to the tip portion, and the operation member opens the valve mechanism in conjunction with the relative movement of the coating liquid storage portion relative to the tip portion.

Description

[0001] Cross-referencing of related applications

[0002] This application claims priority to Japanese Patent Application No. 2021-91605, which is incorporated herein by reference. Technical Field

[0003] This invention relates to writing instruments. Background Technology

[0004] Previously, a type of water-filled brush was known as a writing tool. These brushes were used for calligraphy practice or for painting with water-based paints outdoors.

[0005] For example, Patent Document 1 describes a water-storing brush with a brush tip for applying water and a shaft extending from the brush tip. The shaft has a liquid storage section for storing water. In this water-storing brush, the liquid storage section has a water inlet at the front end and a valve mechanism at the rear end, and also has an operating part for switching the opening and closing state of the valve mechanism. That is, according to this water-storing brush, the user opens the valve mechanism by pushing the operating part, thereby connecting the liquid storage section with the external environment, so that water flows out from the water inlet and can supply water to the brush tip. Thus, in this writing instrument, it is required that an appropriate amount of water be supplied to the brush tip when the user needs it; this is not limited to water, but also applies to writing instruments containing ink.

[0006] Existing technical documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-209531 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] However, in the writing instrument described in Patent Document 1, since the brush tip and the ink reservoir are always connected through the water passage, it is difficult to properly control the supply of ink or other inks simply by operating the control mechanism. Especially when the ink has low viscosity or surface tension, ink may leak out of the water passage even when the valve mechanism is closed. Therefore, it is difficult to accurately control the amount of ink supplied to the brush tip.

[0010] Furthermore, when supplying the coating liquid to the tip of the brush, it is necessary to prevent the coating liquid from leaking out of parts other than the tip. In the water-storing brush of Patent Document 1, since the valve mechanism and the operating part for opening the valve mechanism are located at the rear end, no countermeasures are proposed to prevent the coating liquid from leaking out of these parts.

[0011] In view of the above, the objective of the present invention is to provide a writing instrument that can prevent leakage of ink while more accurately controlling the amount of ink supplied to the pen tip.

[0012] Methods for solving problems

[0013] As one embodiment of the present invention, the writing tool has:

[0014] The tip of the pen used to apply the coating liquid;

[0015] A coating liquid storage unit for storing coating liquid;

[0016] A cylindrical portion formed in a manner that covers the coating liquid storage portion and is fixed to the pen tip;

[0017] A valve mechanism is provided at the front end of the coating liquid storage section;

[0018] An operating component fixed to the pen tip, capable of opening the valve mechanism and allowing the coating liquid flowing from the coating liquid reservoir to flow towards the pen tip via the valve mechanism; and

[0019] An axially expandable cylindrical elastic member connects the valve mechanism and the operating component and defines a flow path for the coating liquid between the valve mechanism and the operating component;

[0020] The liquid reservoir is axially movable relative to the pen tip.

[0021] The operating component opens the valve mechanism as the coating liquid storage section moves relative to the pen tip.

[0022] Furthermore, among the writing instruments, preferably,

[0023] The operating component pushes the valve mechanism to open the valve mechanism.

[0024] Furthermore, among the writing instruments, preferably,

[0025] One end of the cylindrical elastic component covers the valve mechanism and also covers the front end of the coating liquid storage section. Attached Figure Description

[0026] Figure 1 A summary of the internal structure of a writing tool in one implementation.

[0027] Figure 2 yes Figure 1 An exploded diagram of the writing instrument.

[0028] Figure 3 express Figure 1 The writing instrument has an internal structure with a valve mechanism.

[0029] Figure 4 Viewed from the axial rear end side Figure 1 A diagram of the valve mechanism of a writing instrument.

[0030] Figure 5 yes Figure 1 A cross-sectional view of the pushing component of a writing instrument.

[0031] Figure 6 Viewed from the axial rear end side Figure 1 A diagram of the pushing component of a writing instrument.

[0032] Figure 7 yes Figure 1 A cross-sectional view of the cylindrical elastic component of a writing instrument.

[0033] Figure 8 Viewed from one side of the axial direction. Figure 1 A diagram of the cylindrical elastic component of a writing instrument.

[0034] Figure 9 This indicates the relationship between the valve mechanism, the pushing component, and the cylindrical elastic component when the valve mechanism is in the closed state.

[0035] Figure 10 This indicates the relationship between the valve mechanism, the pushing component, and the cylindrical elastic component when the valve mechanism is in the open state. Detailed Implementation

[0036] Hereinafter, a writing instrument for one embodiment of the present invention will be described with reference to the accompanying drawings.

[0037] The writing instrument 1 in this embodiment is filled with ink as a coating. Furthermore, the writing instrument 1 is configured to be refillable with ink when the ink is consumed.

[0038] like Figures 1-2 As shown, the writing instrument 1 of this embodiment has: a pen tip 2 for applying a coating liquid to a coating object such as paper; and a shaft 3 extending from the pen tip 2. The shaft 3 has: a coating liquid storage section 31 for storing the coating liquid; and a cylindrical section 32 formed in a cylindrical shape to cover the coating liquid storage section 31.

[0039] In this specification, the direction in which the writing instrument 1 extends is referred to as the axial direction, the direction orthogonal to the axial direction is referred to as the radial direction, and the direction around the central axis of the writing instrument 1 is referred to as the circumferential direction. In addition, in the axial direction, the tip side is referred to as the front end side, and the side opposite to the front end side is referred to as the rear end side.

[0040] In this embodiment, the pen tip 2 has: a coating portion 21 that directly contacts the object to be coated and applies a coating liquid to the object; a holding portion 22 that holds the coating portion 21; and a cylindrical hollow portion 23 that extends from the holding portion 22 toward the rear end.

[0041] The coating section 21 is formed from a bundle of hairs, with one end of multiple hairs bound together by an adhesive. That is, the coating section 21 has: a bundled section where one end of multiple hairs is bound by an adhesive; and a non-bundled section where multiple hairs are not bound by an adhesive. The bundled section is located at the rear end of the coating section 21, and the non-bundled section is located at the front end of the coating section 21. Furthermore, an axially extending flow path is formed in the bundled section. The coating liquid is supplied to the front end 211 of the coating section 21 via this flow path. The brush tip 2 having this coating section 21 is specifically a brush tip 2.

[0042] Furthermore, the coating section 21 is formed such that it tapers towards the front end 211 from the rear end 212. Moreover, the rear end 212 has an enlarged diameter section 213, which is formed as the largest outer diameter in the coating section 21.

[0043] In this embodiment, the retaining portion 22 is formed into a frustum shape that tapers from the rear end side toward the front end side. The retaining portion 22 has a through hole 221 extending axially. The through hole 221 has an inner diameter that allows the non-bundled portion of the coating portion 21 to pass through, but prevents the enlarged diameter portion 213 of the coating portion 21 from passing through.

[0044] In this embodiment, the pen tip 2 is fixed to the barrel 32 within the hollow portion 23. The hollow portion 23 is formed such that it fits into the front end portion 321 of the barrel 32 from the outside. Furthermore, the hollow portion 23 and the barrel 32 are configured to engage in a liquid-tight manner. In this embodiment, an internal thread is formed on the inner circumferential surface of the rear end portion 232 of the hollow portion 23, and an external thread is formed on the outer circumferential surface of the front end portion 321 of the barrel 32, which can thread with the internal thread. Thus, the hollow portion 23 and the barrel 32 can be threadedly engaged.

[0045] Furthermore, an annular sealing member 4 is provided inside the hollow portion 23. The sealing member 4 is configured such that, with the pen tip 2 fixed to the barrel 32, the sealing member 4 is clamped between the rear end portion 222 of the retaining portion 22 and the front end portion 321 of the barrel 32. Additionally, the sealing member 4 has an opening 41 through which ink can pass. The inner diameter of the opening 41 is larger than the inner diameter of the flow path of the coating portion 21 and smaller than the outer diameter of the expanded diameter portion 213 of the coating portion 21. The sealing member 4 is configured such that its opening 41 communicates with the flow path of the coating portion 21. Through this sealing member 4, ink flowing from the coating liquid storage portion 31 is easily guided through the opening 41 into the flow path in the coating portion 21, thereby facilitating the supply of ink to the pen tip 2.

[0046] The ink reservoir 31 is formed into a bottomed cylindrical shape, having an open front end 311 and a closed rear end 312. The ink reservoir 31 has an internal space S for filling with ink. Within its internal space S, the ink reservoir 31 houses a spherical mixing component 314 that promotes ink mixing. The mixing component 314 has a diameter smaller than the inner diameter of the ink reservoir 31, thereby moving axially within the internal space S due to axial oscillation of the writing instrument 1. The mixing component 314 typically has a density greater than that of the ink. Therefore, the mixing component 314 sinks in the ink.

[0047] The ink can be either water-based or oil-based.

[0048] The cylindrical portion 32 is formed as a cylinder with openings at both the front end 321 and the rear end 322. The cylindrical portion 32 is configured to house the coating liquid storage portion 31 within it. Additionally, as... Figure 1 As shown, a gap G1 is formed between the inner circumferential surface of the barrel portion 32 and the outer circumferential surface of the ink reservoir portion 31, thereby allowing the ink reservoir portion 31 to move axially within the barrel portion 32. Furthermore, the ink reservoir portion 31 can move axially relative to the pen tip portion 2. Alternatively, a portion of the inner circumferential surface of the barrel portion 32 can be slidably contacted with a portion of the outer circumferential surface of the ink reservoir portion 31, thereby allowing the ink reservoir portion 31 to move within the barrel portion 32.

[0049] Furthermore, the cylindrical portion 32 is formed such that the rear end portion 312 of the coating liquid reservoir 31 is exposed. As a result, the user can easily push the rear end portion 312 (preferably the rear end face of the coating liquid reservoir 31) of the coating liquid reservoir 31 with his thumb or the like, thereby easily moving the coating liquid reservoir 31 toward the front end side.

[0050] The writing instrument 1 also includes: a valve mechanism 5 located at the front end 311 of the ink reservoir 31; and an operating member 6, i.e., a pushing member 6, which opens the valve mechanism 5 by pushing it. In this embodiment, the pushing member 6 is fixed to the front end 321 of the cylindrical portion 32. In addition, in this embodiment, the pushing member 6 is directly fixed to the cylindrical portion 32.

[0051] The writing instrument 1 is configured to be in both a closed and an open state: the closed state is when the pushing member 6 does not push the valve mechanism 5 to open it, thus closing the valve mechanism 5; the open state is when the coating reservoir 31 moves towards the front end, and the pushing member 6 pushes the valve mechanism 5, thus opening the valve mechanism 5. Furthermore, this allows the valve mechanism 5 to move axially relative to the pushing member 6. In the closed state, the portion of the pushing member 6 that pushes the valve mechanism 5 (specifically, the protrusion 63 described later) can either contact the valve mechanism 5 or move away from it. In other words, a clearance portion can be provided between the valve mechanism 5 and the portion of the pushing member 6 that pushes the valve mechanism 5, or this clearance portion can be omitted.

[0052] In addition, the writing instrument 1 has a cylindrical elastic component 7 that connects the valve mechanism 5 and the pushing component 6.

[0053] like Figure 3 and Figure 4 As shown, the valve mechanism 5 of this embodiment includes: a valve body 51 having an axially extending flow path 511 formed inside; a valve core 52 capable of moving axially within the flow path 511; a valve seat portion 53 for the valve core 52 to abut against in a manner capable of closing the flow path 511; and a spring member 54 for pressing the valve core 52 against the valve seat portion 53.

[0054] The valve body 51 is formed in an axially extending cylindrical shape to accommodate the valve core 52 and the valve seat portion 53. Furthermore, the valve body 51 has an annular locking portion 512 that restricts the entire valve body 51 from entering the interior of the coating liquid reservoir 31. Moreover, the valve body 51 extends from the locking portion 512 towards its rear end and has an insertion portion 513 disposed inside the coating liquid reservoir 31.

[0055] The outer diameter of the locking part 512 is larger than the inner diameter of the front end part 311 of the coating liquid storage part 31.

[0056] The locking portion 512 in this embodiment can also function as a first elastic member connecting portion 512 connecting the rear end portion 72 of the cylindrical elastic member 7. The outer diameter of the locking portion 512 is formed to be smaller than the outer diameter of the front end portion 311 in the coating liquid storage portion 31. As a result, the connection portion between the locking portion 512 and the coating liquid storage portion 31 becomes a state in which it gradually widens from the locking portion 512 toward the front end portion 311 of the coating liquid storage portion 31.

[0057] The insertion portion 513 has a first extension 513a, which extends from the locking portion 512 toward the rear end and is configured to contact the inner peripheral surface of the coating liquid reservoir 31 in the circumferential direction. Additionally, the insertion portion 513 has a second extension 513b, which extends further from the first extension 513a toward the rear end and is configured to taper toward the front end of the rear end. The second extension 513b is configured such that its outer peripheral surface does not contact the inner peripheral surface of the coating liquid reservoir 31.

[0058] The valve core 52 has: an abutting portion 521 that abuts against the valve seat portion 53; a first valve stem portion 522 that extends from the abutting portion 521 toward the front end side; and a second valve stem portion 523 that extends from the abutting portion 521 toward the rear end side.

[0059] The abutting portion 521 is configured to abut against the valve seat portion 53 from the rear end side toward the front end side (by moving from the rear end side to the front end side in the axial direction). The abutting portion 521 is formed into a frustum shape that tapers from the rear end side toward the front end side, and has an abutting surface 521a that abuts against the valve seat portion 53 in the radial range.

[0060] The first valve stem portion 522 is configured such that, when the abutting portion 521 abuts against the valve seat portion 53, its front end portion 522a protrudes from the valve body 51. Furthermore, the first valve stem portion 522 is cylindrical.

[0061] The second valve stem portion 523 is configured such that, with the abutment portion 521 moving away from the valve seat portion 53 toward the rear end, its rear end portion 523a protrudes from the valve body 51. Through this second valve stem portion 523, the mixing component 314, which closes the flow path 511 of the valve body 51 from the rear end, can move away from the valve body 51.

[0062] The valve seat portion 53 has an abutment portion 531 for the valve core 52 to abut. The abutment portion 531 has an abutment surface 531a with a shape corresponding to the abutment surface 521a of the valve core 52. In other words, the abutment portion 531 is formed in a way that extends through in the axial direction and is formed into a frustum shape with an inner diameter that expands from the front end side to the rear end side.

[0063] The front end of the spring member 54 abuts against the valve core 52, and the rear end abuts against the insertion portion 513 of the valve body 51. This configuration of the spring member 54 results in a contracted state where it contracts axially as the coating reservoir 31 moves towards the front end. Specifically, as the coating reservoir 31 moves towards the front end, the valve core 52 is pushed by the pushing member 6, thereby causing the spring member 54 to contract under the pressure of the valve core 52 moving towards the rear end. Furthermore, as the coating reservoir 31 moves towards the rear end, the valve core 52 is released from the pushing member 6, and the spring member 54 extends, pressing the valve core 52 towards the front end by abutting against the valve seat portion 53.

[0064] The spring component 54 in this embodiment is more specifically a disc spring.

[0065] like Figure 5 and Figure 6 As shown, the pushing member 6 of this embodiment has: a cylindrical locking portion 61 that restricts the entire pushing member 6 from entering the interior of the cylindrical portion 32; a cylindrical second elastic member connecting portion 62 that extends from the locking portion 61 toward the rear end and becomes part of the front end portion 71 of the cylindrical elastic member 7; a rod-shaped protrusion 63 that protrudes further toward the rear end than the second elastic member connecting portion 62 and directly pushes the valve mechanism 5; and a support portion 64 that supports the protrusion 63 on the locking portion 61 or the second elastic member connecting portion 62.

[0066] The pressing member 6 is configured such that its locking part 61 abuts against the front end 321 of the cylindrical part 32.

[0067] The outer diameter of the second elastic member connecting portion 62 is formed to be smaller than the inner diameter of the front end portion 321 of the cylindrical portion 32. Therefore, as... Figure 1 As shown, a gap G2 for arranging the cylindrical elastic member 7 can be formed between the outer peripheral surface of the second elastic member connecting portion 62 and the inner peripheral surface of the front end portion 321 of the cylindrical portion 32.

[0068] The protrusion 63 is formed to be inserted into the interior of the first valve stem portion 522 of the valve core 52. Thus, the protrusion 63 is guided by the first valve stem portion 522 to abut against the valve core 52. In this embodiment, the protrusion 63 is disposed inside the first valve stem portion 522 in both the closed and open states of the valve mechanism 5. Furthermore, the protrusion 63 can also be disposed outside the first valve stem portion 522 in the closed state of the valve mechanism 5.

[0069] The support portion 64 has one or more support pieces 641, which are formed to extend from the base end 631 of the protrusion 63 onto the inner circumferential surface of the locking portion 61 or the second elastic member connecting portion 62. Furthermore, the support portion 64 is formed to have ink flow paths 642. In this embodiment, the support portion 64 is formed in a cross shape, having four support pieces 641 extending radially in four directions from the base end 631 of the protrusion 63. Additionally, four flow paths 642 are formed between each support piece 641.

[0070] like Figure 1 , Figure 2 , Figure 7 ,and Figure 8 As shown, the cylindrical elastic member 7 connects the valve mechanism 5 and the pushing member 6 such that its front end 71 covers the second elastic member connecting portion 62 of the pushing member 6, and its rear end 72 covers the locking portion 512 of the valve mechanism 5, i.e., the first elastic member connecting portion 512. The cylindrical elastic member 7 has a flow path 73, which, when the valve mechanism 5 is in the open state, causes the ink flowing out of the valve mechanism 5 to move from the valve mechanism 5 to the pushing member 6.

[0071] In this embodiment, the rear end 72 of the cylindrical elastic member 7 extends beyond the first elastic member connecting portion 512 of the valve mechanism 5 and covers a portion of the front end 311 of the coating liquid storage portion 31. That is, the cylindrical elastic member 7 reinforces the fixation of the valve mechanism 5 to the coating liquid storage portion 31. Furthermore, the cylindrical elastic member 7 also covers the connection portion between the valve mechanism 5 and the coating liquid storage portion 31 to prevent leakage of the coating liquid.

[0072] like Figure 9 and Figure 10 As shown, the cylindrical elastic member 7 connecting the valve mechanism 5 and the pushing member 6 forms a telescopic portion 74 capable of axial extension and retraction between the front end 71 and the rear end 72. Figure 10 As shown, with the movement of the coating liquid storage section 31 towards the front end, the cylindrical elastic member 7 becomes axially contracted. Specifically, as the movement of the coating liquid storage section 31 towards the front end causes the valve mechanism 5 to approach the pushing member 6, the cylindrical elastic member 7 receives axial pushing forces from both the valve mechanism 5 and the pushing member 6, thereby causing the telescopic section 74 to become axially contracted. Furthermore, as... Figure 9 As shown, as the coating liquid storage section 31 moves towards the rear end, causing the valve mechanism 5 to move away from the pushing member 6, the cylindrical elastic member 7 bears axial tensile forces from both the valve mechanism 5 and the pushing member 6. Consequently, the telescopic section 74 becomes (from a contracted state) an axially extended state. Figure 9 ).

[0073] In addition, such as Figure 10As shown, the cylindrical elastic member 7 of this embodiment is configured such that, when the telescopic portion 74 is in a contracted state, the telescopic portion 74 becomes radially inwardly narrowed or flexed. Furthermore, the cylindrical elastic member 7 can also be configured such that, when the telescopic portion 74 is in a contracted state, the telescopic portion 74 becomes radially outwardly widened.

[0074] Furthermore, the cylindrical elastic member 7 in this embodiment is configured such that, when the telescopic portion 74 is in an extended state, the inner circumferential surface of the telescopic portion 74 becomes a cylindrical shape that is approximately straight along the axial direction.

[0075] As the material constituting the tubular elastic component 7, thermoplastic elastomer materials can be listed as an example.

[0076] As described above, the writing instrument 1 of this embodiment has:

[0077] 2. The pen tip 2 for applying the coating liquid;

[0078] Coating liquid storage unit 31 for storing coating liquid;

[0079] The cylindrical portion 32 is formed in a cylindrical shape and fixed to the pen tip portion 2 in a manner that covers the coating liquid storage portion 31;

[0080] A valve mechanism 5 is provided at the front end 311 of the coating liquid storage section 31;

[0081] An operating component 6 fixed to the pen tip 2, which is capable of opening the valve mechanism 5 and allowing the coating liquid flowing from the coating liquid storage section 31 to flow towards the pen tip side via the valve mechanism 5; and

[0082] An axially expandable cylindrical elastic member 7 connects the valve mechanism 5 and the operating member 6, and defines a flow path for the coating liquid between the valve mechanism 5 and the operating member 6.

[0083] The liquid storage section 31 is axially movable relative to the pen tip 2.

[0084] The operating component 6 opens the valve mechanism 5 as the coating liquid storage part 31 moves relative to the pen tip part 2.

[0085] The writing instrument 1 with this structure, having a cylindrical elastic member 7 connecting the valve mechanism 5 and the operating member 6, prevents ink leakage between them. Furthermore, the ink reservoir 31 can move axially relative to the pen tip 2, and the operating member 6, accompanying the relative movement of the ink reservoir 31, opens the valve mechanism 5. This allows ink to be discharged from the ink reservoir 31 via the flow path 73 between the valve mechanism 5 and the cylindrical elastic member 7, and ink to be supplied to the pen tip 2. Moreover, since the front end 311 of the ink reservoir 31 is sealed by the valve mechanism 5 when it is closed, the possibility of ink accidentally flowing from the front end 311 towards the pen tip is prevented. Therefore, according to the above structure, the user operates the opening and closing of the valve mechanism 5 by moving the ink reservoir 31 relative to the pen tip 2, thereby enabling more precise control of the amount of ink supplied to the pen tip 2.

[0086] In addition, in the writing instrument 1 of this embodiment, the operating component 6 pushes the valve mechanism 5 to make the valve mechanism 5 open.

[0087] The writing instrument 1 with this structure can be made relatively simple because the operating component 6 pushes the valve mechanism 5 to open the valve mechanism 5.

[0088] In addition, in the writing instrument 1 of this embodiment, one end (rear end 72) of the cylindrical elastic member 7 covers the valve mechanism 5 and also covers the front end 311 of the coating liquid storage part 31.

[0089] With this structure, the writing instrument 1 can prevent leakage of coating liquid from the gap between the valve mechanism 5 and the coating liquid storage section 31, since one end (rear end 72) of the cylindrical elastic member 7 covers the valve mechanism 5 and also covers the front end 311 of the coating liquid storage section 31.

[0090] Furthermore, with the writing instrument 1 of this embodiment, by pushing the ink reservoir 31 towards the front end, the telescopic portion 74 of the cylindrical elastic member 7 is in a contracted state. Therefore, the ink reservoir 31 can move towards the pushing member 6 along with the valve mechanism 5 by the amount of the contracted length of the telescopic portion 74. Moreover, the abutment portion 521 of the valve mechanism 5 is pushed by the protrusion 63 of the pushing member 6, thereby opening the valve mechanism 5. Accompanyingly, the ink discharged from the ink reservoir 31 moves towards the front end via the flow path 511 of the valve mechanism 5, the flow path 73 of the cylindrical elastic member 7, and the flow path 642 of the pushing member 6 and is supplied to the pen tip 2.

[0091] Furthermore, with the writing instrument 1 of this embodiment, the valve mechanism 5 is closed when the ink reservoir 31 is not pushed. Therefore, even when using ink with low viscosity or low surface tension, the ink will not flow out of the pen tip, and the amount of ink supplied can be accurately controlled according to the user's intention.

[0092] Furthermore, since the writing instrument 1 of this embodiment can prevent ink leakage, ink contamination is unlikely to occur, and users can use it with peace of mind.

[0093] Furthermore, with the writing instrument 1 of this embodiment, the locking part 512, that is, the connection part between the first elastic member connecting part 512 and the coating liquid storage part 31, is gradually widened from the first elastic member connecting part 512 toward the front end part 311 of the coating liquid storage part 31. Therefore, the cylindrical elastic member 7 can be easily installed from the first elastic member connecting part 512 to the front end part 311.

[0094] Furthermore, with the writing instrument 1 of this embodiment, since the cylindrical elastic member 7 covers the front end portion 311 of the ink reservoir 31 from the first elastic member connecting portion 512, ink leakage from the gap formed between the valve mechanism 5 and the ink reservoir 31 can be suppressed. In addition, it is also possible to prevent the valve mechanism 5 from accidentally detaching from the ink reservoir 31.

[0095] Furthermore, in the writing instrument 1 of this embodiment, the telescopic portion 74 of the cylindrical elastic member 7 is configured such that its inner circumferential surface in its extended state is approximately straight along the axial direction. Therefore, ink easily flows from the cylindrical elastic member 7 to the pushing member 6. Consequently, it is difficult for ink to remain inside the cylindrical elastic member 7, and the situation where ink solidifies on the inner circumferential surface of the cylindrical elastic member 7 can be suppressed. Therefore, it is possible to maintain a smooth supply of ink to the pen tip 2 for a long period of time. This is preferable when the writing instrument 1 is of the type that can be refilled with ink.

[0096] Furthermore, in the writing instrument 1 of this embodiment, since the pressing member 6 is directly fixed to the barrel 32, if the pen tip 2 is detached from the barrel 32, the pressing member 6 is exposed at the front end of the barrel 32. In this state, if the rear end of the ink reservoir 31 is pressed, the valve mechanism 5 opens via the pressing member 6 fixed to the barrel 32. Thus, ink can be refilled into the ink reservoir 31 via the flow path 642 of the pressing member 6. When refilling ink, since the pressing member 6 and the valve mechanism 5 are connected by the cylindrical elastic member 7, ink leakage can be suppressed.

[0097] Furthermore, the writing instrument of the present invention is not limited to the structure of the above-described embodiments, and various modifications can of course be made without departing from the spirit of the present invention.

[0098] For example, in the above embodiments, a writing instrument filled with ink as a coating liquid is illustrated, but it is not limited thereto. The writing instrument of the present invention can also be filled with water, ink, etc. as a coating liquid.

[0099] Furthermore, in the above embodiment, the valve mechanism 5 is shown to be able to move axially relative to the pushing member 6, but it is not limited to this and can also be configured such that the pushing member 6 can move axially relative to the valve mechanism 5.

[0100] Furthermore, the pressing member 6 can also be indirectly fixed to the cylinder portion 32, and thus fixed to the cylinder portion 32. In other words, the pressing member 6 can also be configured to be indirectly fixed to the cylinder portion 32 by being fixed to a component other than the cylinder portion 32. For example, the pressing member 6 can also be fixed inside the hollow portion 23 of the pen tip portion 2.

[0101] In addition, the cylindrical elastic member 7 can also be formed into a pleated shape. As a result, the telescopic part 74 can easily extend and retract in the axial direction.

[0102] Explanation of reference numerals in the attached figures

[0103] 1…writing instrument, 2…pen tip, 21…coating part, 211: front end, 212: rear end, 213: enlarged diameter part, 22…holding part, 221…through hole, 222…rear end, 23…hollow part, 3…shaft part, 31…coating liquid storage part, 311…front end, 312…rear end, 314…mixing component, 32…cylinder part, 321…front end, 322…rear end, 4…sealing component, 41…opening, 5…valve mechanism, 51…valve body, 511…flow path, 512…locking part (first elastic member connection part), 513…insertion part, 513a…first extension part, 513b…second extension part, 513c: elastic member fixing part, 52…valve core 521…Abutting part, 521a…Abutting surface, 521b…Elastic member fixing part, 522…First valve stem part, 522a…Front end part, 523…Second valve stem part, 523a…Rear end part, 53…Valve seat part, 531…Abutted part, 531a…Abutted surface, 531c:Shaft seal part, 54…Spring part, 6…Operating part (pushing part), 61…Clocking part, 62:Second elastic member connecting part, 63…Protrusion, 631…Base end, 64…Support part, 641…Support piece, 642…Flow path, 7…Cylindrical elastic member, 71…Front end part, 72…Rear end part, 73…Flow path, 74…Telescopic part, S…Internal space, G1…Gap, G2…Gap

Claims

1. A writing instrument, characterized in that, have: The tip of the pen is where the coating liquid is applied; The coating liquid storage unit stores the coating liquid. The cylindrical portion is formed in a cylindrical shape to cover the coating liquid storage portion and is fixed to the pen tip portion; A valve mechanism is located at the front end of the coating liquid storage section; An operating component fixed to the pen tip is capable of opening the valve mechanism and allowing the coating liquid flowing out of the coating liquid storage section to flow to the pen tip side via the valve mechanism; as well as An axially expandable cylindrical elastic member connects the valve mechanism and the operating component and defines a flow path for the coating liquid between the valve mechanism and the operating component; The liquid reservoir is axially movable relative to the pen tip. The operating component, along with the relative movement of the coating liquid storage section relative to the pen tip, causes the valve mechanism to open. The cylindrical elastic component covers the valve mechanism and also the front end of the coating liquid storage section.

2. The writing instrument according to claim 1, characterized in that, The operating component pushes the valve mechanism to open the valve mechanism.

3. The writing instrument according to claim 1 or 2, characterized in that, The operating component has: a cylindrical second elastic member connecting portion that forms part of the front end of the cylindrical elastic member; and a protrusion that protrudes further rearward than the second elastic member connecting portion and pushes against the valve mechanism. The cylindrical elastic component is connected to the connecting part of the second elastic component.

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