Writing instrument
Patent Information
- Application Number
- JP2023146521
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-09-08
- Publication Date
- 2026-03-02
AI Technical Summary
When using soft refills, it is difficult to control the amount of liquid release and it is easy to cause sudden liquid outflow (so-called dropping of the ball).
A writing tool is designed that contains a valve mechanism inside the refill. When the side of the refill is pressed, the valve opens to limit the flow of liquid through the runner resistance valve to prevent the liquid from suddenly flowing out.
It effectively prevents the sudden outflow of liquid, improves the control accuracy of liquid release, and makes the use process more stable.
Smart Images
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Abstract
Description
[Technical field]
[0001] The present disclosure relates to a writing instrument that has a valve mechanism inside a barrel and supplies ink by pressing the barrel. [Background technology]
[0002] Conventionally, so-called valve-type felt-tip pens, which have a valve mechanism inside the barrel, have been known to open the valve by pressing the pen tip with writing pressure (Patent Document 1) or by knocking the rear end (Patent Document 2). However, these methods have problems such as not being able to use soft pen tips such as brush tips as the pen tip, and difficulty in controlling the amount of liquid dispensed. Also, a writing instrument has been disclosed in which the internal valve mechanism is closed by attaching a cap (Patent Document 3). [Prior art documents] [Patent documents]
[0003] [Patent Document 1] JP 2014-87947 A [Patent Document 2] Japanese Patent Application Publication No. 9-271710 [Patent Document 3] JP 2021-115710 A Summary of the Invention [Problem to be solved by the invention]
[0004] In particular, the technology described in Patent Document 1 makes it possible to prevent the direct current phenomenon in which a large amount of ink unintentionally flows out, also known as "drip," which is the phenomenon of ink or coating liquid blowing out. However, in a felt-tip pen that uses an elastic blow container for the barrel and has a mechanism for opening the valve by pressing the side of the container to allow the liquid to flow out, the liquid sometimes gushes out when the valve is opened. Therefore, the objective of the present disclosure is to prevent sudden liquid outflow (so-called drip) in a writing instrument with a valve that opens when the main body is pressed, and to make it easy to control the amount of liquid discharged by varying the strength of the pressure. [Means for solving the problem]
[0005] The aspects of the present disclosure are as follows.
[0006] <Aspect 1> The writing instrument of the first aspect includes a barrel having an internal space that serves as an ink storage section for storing ink and that is deformable when a side surface of the barrel is pressed; A writing tip formed as a brush tip made of bundled fibers; A tip barrel into which the writing tip is inserted and which is attached to the tip of the barrel; a valve mechanism that is housed in the tip portion of the barrel and opens when a side surface of the barrel is pressed; a valve insertion member including: a bottom plate located at the tip edge of the valve mechanism and having a valve insertion hole formed at its axis; and a tubular portion inserted into the tip side of the valve mechanism and having a rear accommodation portion formed in its internal space; a flow path resistance valve including: a columnar portion that is accommodated in the rear accommodation portion and has a tip surface that contacts a rear end surface of the bottom plate of the valve insertion member; and an insertion portion that protrudes from the tip surface of the columnar portion and is loosely fitted into the valve insertion hole; In addition to providing The valve mechanism includes: a valve retaining member fixed to the barrel; a valve inserted into the valve holding member and movable in a forward and backward direction; a spring that is inserted into the valve and interposed between the valve and a rear end surface of the flow path resistance valve, and that constantly biases the valve rearward with respect to the valve holding member, A liquid passage groove recessed rearward is formed in part of the tip surface of the cylindrical portion of the flow resistance valve.
[0007] In the writing instrument of embodiment 1, ink is supplied to the writing tip from the barrel via the valve mechanism, but the ink flow path is restricted by the flow path resistance valve, so even if you try to supply ink by pressing the barrel, the outflow of ink is restricted, preventing so-called dripping.
[0008] <Aspect 2> A writing instrument according to a second aspect has the configuration of the first aspect, and further comprises a tip insert that is inserted into the tip of the tip barrel with the writing tip inserted therethrough and has a tip edge exposed from the tip of the tip barrel; a brush tip holding member that is inserted into the front barrel insert and holds the writing tip while the insertion portion of the flow resistance valve is inserted and held at the axis center and an abutment plate formed at the rear end of the front barrel insert is abutted against the rear end of the front barrel insert; The pen further includes a cap that covers the tip of the front barrel and has a plurality of ribs provided therein, the rear ends of which are stepped. With the cap attached to the front barrel, the step of the rib presses the tip of the front barrel insert rearward.
[0009] In the writing instrument of the second aspect, when the cap is attached, the tip of the front barrel insert abuts against the rib in the cap and is pressed and moves backward. Then, the brush tip holding member arranged at the rear end of the front barrel insert moves backward together with the movement of the front barrel insert, and the inserted flow resistance valve presses the valve spring backward, restricting the opening of the valve. In other words, the valve is not opened when the cap is attached. Therefore, even if the barrel is pressed with the cap attached, the leakage of ink is restricted. Effect of the Invention
[0010] A writing instrument with a valve that opens when the body is pressed can prevent sudden liquid outflow (so-called dripping) and make it easy to control the amount of liquid dispensed by varying the strength of pressure. [Brief description of the drawings]
[0011] [Figure 1] FIG. 1 is a front view of a writing instrument according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view of the writing instrument of FIG. 1. [Diagram 3] FIG. 3 is a perspective view showing the writing instrument of FIG. 2 with the cap removed. [Figure 4] 2 is a front view showing the writing instrument of FIG. 1 with the cap removed. FIG. [Diagram 5] FIG. 2 is a parts assembly diagram of the writing instrument of FIG. 1. [Figure 6A] FIG. 2 is a front perspective view of the tip barrel with the writing tip attached. [Figure 6B] FIG. 2 is a front view of the tip barrel with the writing tip attached. [Figure 6C] FIG. 6C is a cross-sectional view taken along line VI-VI of FIG. 6B. [Figure 7] FIG. [Figure 8A] FIG. [Figure 8B] FIG. [Figure 8C] FIG. [Figure 8D] FIG. [Figure 8E] FIG. [Figure 8F] FIG. 8E is a cross-sectional view taken along line VIII-VIII of FIG. 8D. [Figure 9A] FIG. 4 is a front perspective view of the valve retaining member. [Figure 9B] FIG. 4 is a rear perspective view of the valve retaining member. [Figure 9C] FIG. [Figure 9D] FIG. [Figure 9E] FIG. [Figure 9F] FIG. 4 is a bottom view of the valve holding member. [Figure 9G] IXa-IXa cross-sectional view of FIG. 9C. [Figure 9H] FIG. 9B is a cross-sectional view taken along line IXb-IXb of FIG. 9D. [Figure 10A] FIG. [Figure 10B] FIG. [Figure 10C] FIG. [Figure 10D] FIG. [Figure 10E] FIG. [Figure 10F] FIG. [Figure 10G] This is a cross-sectional view of FIG. 10C along Xa-Xa. [Figure 10H] This is a cross-sectional view of Xb-Xb in Figure 10D. [Figure 11A] FIG. 2 is a front perspective view of a flow resistance valve. [Figure 11B] FIG. [Figure 11C] FIG. [Figure 11D] FIG. [Figure 11E] FIG. [Figure 11F] FIG. [Figure 11G] XI-XI cross-sectional view of FIG. 11C. [Figure 12A] FIG. 2 is a front perspective view of the brush tip holding member. [Figure 12B] FIG. [Figure 12C] FIG. [Figure 12D] FIG. [Figure 12E] FIG. 12D is a cross-sectional view taken along line XII-XII of FIG. 12C. [Figure 13] FIG. 13 is a cross-sectional view taken along line XIII-XIII of FIG. [Figure 14A] FIG. 2 is a cross-sectional view taken along the line XIVa-XIVa in FIG. [Figure 14B] This is a cross-sectional view of Figure 14A along XIVb-XIVb. [Figure 15] The tip portion in the state shown in FIG. 13 is shown in an enlarged manner. [Figure 16] 5 is a front view of the writing instrument of FIG. 4 with a side surface of the barrel pressed. [Figure 17] 17 shows an enlarged cross section of the tip portion in the state shown in FIG. 16. [Figure 18] 17 shows an enlarged cross section of the tip portion in a state where pressure is released from the state shown in FIG. 16. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The following describes an embodiment of the present disclosure. Note that reference numerals commonly used in multiple drawings indicate common members or parts even if not specifically described in each drawing. In addition, the dimensions and ratios of each part shown in the drawings do not necessarily match the dimensions and ratios of the actual product. Furthermore, the dimensional relationships and ratios between the drawings may differ.
[0013] In addition, in this disclosure, the side of the writing instrument on which the writing tip is located is referred to as the "tip," the direction toward the tip is referred to as the "forward," the opposite side is referred to as the "rear end," and the direction toward the rear end is referred to as the "publication."
[0014] 1 and 2 are a front view and a perspective view, respectively, showing the appearance of a writing instrument 10 of the present disclosure. A front barrel 12 of approximately cylindrical shape and of approximately the same diameter is attached to the tip of a substantially cylindrical barrel 11, and a cap 13 of approximately cylindrical shape and of approximately the same diameter is further attached to the tip of the front barrel 12. FIGS. 3 and 4 are a perspective view and a front view, respectively, showing a state in which the cap 13 is removed from the state of FIGS. 1 and 2. The front barrel 12 is composed of a substantially cylindrical covering portion 12A that covers the tip portion of the barrel 11, an outer peripheral locking portion 12B that is located on the tip side of the front barrel 12A and has a protrusion formed on the outer periphery for engaging with the cap 13 while being slightly reduced in diameter, and a tapered portion 12C that is tapered toward the front at the tip and has an open tip. From the opening at the tip of the tapered portion 12C, there are exposed a writing tip 14 formed as a brush tip 14A made of bundled fine fibers, and the tip edge of a front barrel insert 15 which is inserted into the tip of the front barrel 12 with the writing tip 14 inserted therethrough.
[0015] Fig. 5 is a perspective view showing an assembly diagram of the writing implement of Fig. 1. The barrel 11 is composed of a hollow, substantially cylindrical large diameter section 11A and a small diameter section 11B formed by reducing the diameter at the tip side of the barrel 11. The internal space of the barrel 11 serves as an ink storage section 11C (see Fig. 13) for storing ink. The barrel 11 is made of a relatively soft and flexible synthetic resin (such as polypropylene resin or low-density polyethylene resin), and is deformable as shown in Fig. 13 when the side surface is pressed.
[0016] The writing tip 14 is composed of a brush tip 14A formed by bundling fine fibers and tapered, and a flange 14B with an enlarged diameter at the rear end. As described above, the front barrel 12 is composed of a covering portion 12A, an outer peripheral locking portion 12B, and a tapered portion 12C. The front barrel insert 15 is composed of a cylindrical front portion 15A and a rear portion 15B located behind the front portion and enlarged in diameter. The O-ring 16 is made of silicone rubber and formed in an annular shape. The writing tip 14 is inserted into the inside of the front barrel 12. The covering portion 12A of the front barrel 12 is pressed in so as to cover the small diameter portion 11B of the barrel, and the front barrel 12 is attached to the tip of the barrel 11. When the cap 13 is attached, the tapered portion 12C is covered, and the inner peripheral locking portion 13A (see FIG. 14A), which is a protrusion formed on the inner surface of the cap 13, is locked with the outer peripheral locking portion 12B. 14A, a plurality of ribs 13C are provided inside cap 13, which covers the tip of front barrel 12. Ribs 13C reach from the tip to the middle of the inner circumferential surface of cap 13, and their rear ends form steps 13B.
[0017] The brush tip holding member 20 is formed as a generally cylindrical member with a flange formed on the rear end edge. The detailed structure will be described later.
[0018] The valve mechanism 40 is housed in the tip portion of the barrel 11, interposed between the ink storage section 11C (see Fig. 13) and the brush tip holding member 20 (see Fig. 5), and is a member that opens when the side surface of the barrel 11 is pressed (see Fig. 16). The valve mechanism 40 has a substantially cylindrical valve holding member 50 fixed to the barrel, a valve 60 (see Fig. 7) inserted into the valve holding member 50 and movable in the front-rear direction, a valve insertion member 41 inserted inside the rear end of the valve holding member 50, and a flow path resistance valve 30 whose tip portion protrudes from the valve insertion member 41.
[0019] 6A to 6C are a front perspective view (FIG. 6A), a front view (FIG. 6B), and a VI-VI cross-sectional view of front barrel 12 with writing tip 14 attached thereto. As shown in FIG. 6C, the internal space of tapered portion 12C of front barrel 12 is formed of front insertion hole 12D located on the tip side and having a small inner diameter, and rear insertion hole 12E located at the rear of front barrel 12 and having a larger inner diameter. As shown in FIG. 6C, an O-ring 16 is inserted into the step between front insertion hole 12D and rear insertion hole 12E of front barrel 12. Then, front barrel insert 15 is inserted from the rear end of front barrel 12 so that front portion 15A is located in front insertion hole 12D and rear portion 15B is located in rear insertion hole 12E. Next, writing tip 14 is inserted from the rear end of front barrel 12 by inserting brush tip 14A through front portion 15A of front barrel insert 15 and bending flange 14B to the right at the step between front portion 15A and rear portion 15B. Finally, brush tip holding member 20 is inserted from the rear end of front barrel 12 by positioning insertion portion 21 (FIG. 12C) at rear portion 15B of front barrel insert 15 and abutting contact plate 22 (FIG. 12C) against the rear end edge of rear portion 15B. In this state, as shown in FIGS. 6A and 6B, the tip portion of writing tip 14 and the tip portion of front barrel insert 15 protrude from the opening at the tip of front barrel 12.
[0020] 7 is a parts assembly diagram of the valve mechanism 40. A spring 42 is interposed between the valve 60 inserted in the valve holding member 50 and the flow path resistance valve 30 inserted in the valve insertion member 41, so that the valve 60 is always biased backward with respect to the valve holding member 50.
[0021] 8A to 8F are a front perspective view (FIG. 8A), a rear perspective view (FIG. 8B), a front view (FIG. 8C), a plan view (FIG. 8D), a bottom view (FIG. 8E), and a cross-sectional view (FIG. 8F) taken along line VIII-VIII of FIG. 8D of the valve insertion member 41. The valve insertion member 41 includes a flange-shaped bottom plate 41A and a cylindrical portion 41B having a smaller diameter at the rear of the bottom plate 41A. The bottom plate 41A is located at the tip edge of the valve mechanism 40, and a valve insertion hole 41C is formed in its axis. The cylindrical portion 41B is inserted into the tip side of the valve mechanism 40, and a rear accommodation portion 41D is formed in the internal space.
[0022] 9A to 9H are a front perspective view (FIG. 9A), a rear perspective view (FIG. 9B), a front view (FIG. 9C), a side view (FIG. 9D), a plan view (FIG. 9E), a bottom view (FIG. 9F), a IXa-IXa cross-sectional view (FIG. 9G) of FIG. 9C, and a IXb-IXb cross-sectional view (FIG. 9H) of FIG. 9D of the valve holding member 50. The valve holding member 50 has a flange-shaped leading edge 51, a smaller diameter accommodating tube portion 52 at the rear thereof, a smaller diameter liquid-passing tube portion 53 at the rear thereof, and a smaller diameter annular portion 54 at the rear thereof. A pair of first inlet holes 55 are formed on the side surface of the liquid-passing tube portion 53. The valve holding member 50 is formed hollow, and its internal space becomes an accommodating hole 56, in which the valve 60 is accommodated. A step is formed on the inner surface between the accommodating tube portion 52 and the liquid-passing tube portion 53, which becomes a blocking step 58. The bottom plate 41A of the valve insertion member 41 (FIGS. 8A to 8F) is in contact with and fixed to the leading edge of the valve holding member 50. Moreover, the cylindrical portion 41B constituting the rear end portion of the valve insertion member 41 (FIGS. 8A to 8F) is inserted into the leading end portion of the valve holding member 50.
[0023] 10A to 10H are a front perspective view (FIG. 10A), a rear perspective view (FIG. 10B), a front view (FIG. 10C), a side view (FIG. 10D), a plan view (FIG. 10E), a bottom view (FIG. 10F), a Xa-Xa cross-sectional view (FIG. 10G) of FIG. 10C, and a Xb-Xb cross-sectional view (FIG. 10H) of FIG. 10D. The valve 60 includes a cylindrical liquid passage tube 63 located at the front, an intermediate zone 64 that expands slightly in diameter at the rear thereof, a blocking slope 65 that tapers in diameter at the rear thereof, and a cylindrical vent tube 66 that is smaller in diameter than the liquid passage tube 63 at the rear thereof. The internal space of the liquid passage tube 63 is a second circulation hole 69A, and the internal space of the vent tube 66 is a vent hole 69B.
[0024] The valve 60 is formed by two-color molding of a rigid portion 61 made of a synthetic resin having a relatively high rigidity and an elastic portion 62 located at the rear end and made of a synthetic resin having a higher elasticity. The elastic portion 62 is composed of a band-shaped portion 62A that covers a portion slightly forward from the rear end in a band shape, an annular portion 62B that covers the rear end in a ring shape, a pair of connecting portions 62C that connect the band-shaped portion 62A and the annular portion 62B at the side, and a diaphragm 62D that is recessed forward from the annular portion 62B. The outer peripheral surface near the rear end of the ventilation tube 66 is a covered portion 67B where the portion that abuts on the band-shaped portion 62A, the annular portion 62B, and the connecting portion 62C is covered by the elastic portion 62. The portion of the rigid portion 61 that is surrounded by the elastic portion 62 is an exposed portion 67A.
[0025] 11A to 11G are a front perspective view (FIG. 11A), a rear perspective view (FIG. 11B), a front view (FIG. 11C), a side view (FIG. 11D), a plan view (FIG. 11E), a bottom view (FIG. 11F), and a cross-sectional view (FIG. 11G) taken along line XI-XI of FIG. 11C of the flow resistance valve 30. The flow resistance valve 30 includes a substantially cylindrical columnar portion 31, a substantially cylindrical insertion portion 32 protruding from the center of the tip surface of the columnar portion 31, and a substantially cylindrical protruding portion 33 whose diameter is enlarged on the tip side of the insertion portion 32. A pair of liquid passage grooves 34 are formed in a part of the tip surface of the columnar portion 31, the insertion portion 32 being sandwiched between the pair of liquid passage grooves 34 recessed rearward. The portion from the tip of the protruding portion 33 to the middle of the insertion portion 32 is divided into two by a notch portion 35. The formation of the notch 35 allows the two halves of the protruding portion 33 and the insertion portion 32 to bend toward the axial direction. The columnar portion 31 is accommodated in the rear accommodation portion 41D (FIG. 8F) of the valve insertion member 41, and the tip surface of the columnar portion 31 contacts the rear end surface of the bottom plate (FIG. 8F) of the valve insertion member 41. The insertion portion 32 is inserted into the valve insertion hole 41C (FIGS. 8A, 8B, and 8F) of the valve insertion member 41.
[0026] 12A to 12E are a front perspective view (FIG. 12A), a rear perspective view (FIG. 12B), a front view (FIG. 12C), a bottom view (FIG. 12D), and a cross-sectional view (FIG. 12E) taken along line XII-XII of FIG. 12C of the brush tip holding member 20. The brush tip holding member 20 has a substantially cylindrical insertion portion 21 and an abutment plate 22 formed at its rear end and having an expanded diameter. A through hole 23 is formed in the axis of the abutment plate 22, through which the insertion portion 32 (FIGS. 11A to 11C) of the flow resistance valve 30 is inserted. A plurality of peripheral grooves 23A are formed radially around the through hole 23 (FIG. 12D). The internal space of the insertion portion 21 serves as a front accommodation portion 24 that accommodates and holds the protrusion 33 of the flow resistance valve 30.
[0027] Fig. 13 is a cross-sectional view taken along line XIII-XIII in Fig. 4, showing a side cross-sectional view of the writing instrument 10. Fig. 14A is a cross-sectional view taken along line XIVa-XIVa in Fig. 1, showing a side cross-sectional view of the writing instrument 10. Fig. 14B is a cross-sectional view taken along line XIVb-XIVb in Fig. 14A, showing a front cross-sectional view of the writing instrument. The assembly of the writing instrument 10 will be described with reference to the previous figures.
[0028] First, O-ring 16 is inserted into front barrel 12, then front barrel insert 15 is inserted, and then writing tip 14 is inserted. At this time, brush tip 14A of writing tip 14 and front portion 15A of front barrel insert 15 (see FIG. 5) are inserted into front insertion hole 12D (FIG. 6C) of front barrel 12. Then, flange 14B (FIG. 3) of writing tip 14 abuts against a step formed inside rear portion 15B of front barrel insert 15 (FIG. 6C).
[0029] Next, brush tip holding member 20 is inserted into tip barrel 12. At this time, brush tip holding member 20 is housed in rear insertion hole 12E of tip barrel 12, while insertion portion 21 (Figs. 12A, 12C) is inserted into rear portion 15B of tip barrel insert 15 (Fig. 6C). In addition, abutment plate 22 (Figs. 12B, 12C) formed at the rear end of brush tip holding member 20 abuts against the rear end of tip barrel insert 15 (Fig. 6C). In this state, the tip edge of brush tip holding member 20 presses flange 14B (Fig. 5) of writing tip 14 forward and holds it (Fig. 6C).
[0030] Meanwhile, the valve 60 (Fig. 7) is inserted from the tip of the valve holding member 50 (Fig. 7) and the blocking slope 65 (Figs. 10D, 10G, 10H) is brought into contact with the blocking step 58 (Figs. 9G, 9H). At this time, the vent tube 66 (Fig. 10C) of the valve 60 is located inside the liquid passage tube portion 53 (Figs. 9G, 9H) of the valve holding member 50, and the liquid passage tube 63 is located in the accommodation hole 56 (Figs. 9G, 9H) of the valve holding member 50.
[0031] Then, the spring 42 (FIG. 7) is inserted into the second communication hole 69A of the valve 60. Also, the insertion portion 32 (FIGS. 11A to 11D) of the flow path resistance valve 30 is inserted from the rear into the valve insertion hole 41C (FIGS. 8A, 8D) of the valve insertion member 41, and the protruding portion 33 penetrates forward. In this state, the flow path resistance valve 30 is inserted from the tip of the valve holding member 50, and the tubular portion 41B of the valve insertion member 41 is press-fitted into the tip of the valve holding member 50. At this time, the bottom plate 41A (FIGS. 8C, 8F) of the valve insertion member 41 abuts against the tip edge 51 (FIGS. 9C, 9D, 9G, 9H) of the valve holding member 50. In this state, the spring 42 (FIG. 7) is supported between the cylindrical portion 31 (FIGS. 11A to 11D) of the flow resistance valve 30 and the step between the second flow hole 69A and the air hole 69B of the valve 60 (FIGS. 10G and 10H), thereby constantly biasing the valve 60 backward.
[0032] The valve mechanism 40 is formed by mounting the valve insertion member 41, through which the valve 60, the spring 42, and the flow path resistance valve 30 are inserted, on the valve holding member 50. The valve mechanism 40 is inserted into the barrel 11 (FIG. 13) in a state in which the ink storage section 11C is filled with ink 11D. At this time, the storage tube section 52 (FIGS. 10G and 10H) of the valve holding member 50 is located inside the small diameter section 11B (FIG. 3) of the barrel 11, and the liquid passage tube section 53 (FIGS. 10G and 10H) is located at the tip of the ink storage section 11C (FIG. 13). Furthermore, the tip edge 51 (FIGS. 9G and 9H) of the valve holding member 50 abuts against the tip edge of the small diameter section 11B (FIG. 5) of the barrel 11 (FIG. 13).
[0033] Then, covering portion 12A (Fig. 5) of front barrel 12 is caused to cover small diameter portion 11B (Fig. 5) of barrel tube 11. At the same time, protruding portion 33 (Figs. 11A-11D) of flow path resistance valve 30 passes through through hole 23 (Fig. 12B) of brush tip holding member 20 while bending in the axial direction. Then, when protruding portion 33 passes completely through through hole 23, the bending in the axial direction is released and it returns to the original state shown in Fig. 11A. In this state, the step between protruding portion 33 and insertion portion 32 engages with the edge of through hole 23, so that protruding portion 33 cannot slip out backward. In this state, writing instrument 10 shown in Fig. 13 is completed.
[0034] When the tapered portion 12C of the front barrel 12 of the writing instrument 10 in the state shown in FIG. 13 is inserted from the rear end of the cap 13 and the inner circumferential locking portion (FIG. 13) is engaged with the outer circumferential locking portion 12B (FIG. 3), the writing instrument is in the state shown in FIG. 1 and FIG. 3. FIG. 14A is a side cross-sectional view at this time, and FIG. 14B is a front cross-sectional view. In this state, the tip of the front barrel insert 15 protruding from the tip of the front barrel 12 abuts against the step at the rear end of the rib 13C inside the cap 13 and is pressed backward. As a result, the flow path resistance valve 30 is also pressed backward, compressing the spring 42 and pressing the valve 60 backward. In other words, with the cap 13 attached to the front barrel 12, the step of the rib 13C presses the tip of the front barrel insert 15 backward. In this state, forward movement of the valve 60 is prevented, and the blocking slope 65 of the valve 60 is maintained in close contact with the blocking step 58 of the valve holding member 50. As a result, with the cap 13 attached, ink 11D will not spurt out from the writing tip 14 even if sudden pressure is applied, such as when the barrel 11 is stepped on.
[0035] Fig. 15 is an enlarged view of the tip portion in Fig. 13. In this state, the valve 60 is biased backward by the spring 42, so that the blocking slope 65 of the valve 60 comes into close contact with the blocking step 58 of the valve holding member 50. As a result, the ink 11D that has entered the inside of the valve mechanism 40 from the first inlet 55 cannot flow between the valve holding member 50 and the valve 60, and the ink 11D is not supplied to the writing tip 14. In other words, when the valve 60 is biased backward, the gap between the valve holding member 50 and the valve 60 is closed, preventing the flow of the ink 11D.
[0036] FIG. 16 is a front view of the writing instrument 10 with the cap 13 removed, with the side of the barrel 11 pressed. FIG. 17 is an enlarged view of the tip portion of FIG. 16. When the side of the barrel 11 is pressed as shown in FIG. 16, the pressure inside the ink storage section 11C increases. This increased pressure presses the valve 60 forward as shown in FIG. 17 against the biasing force of the spring 42. FIG. 15 is an enlarged view of only the valve mechanism 40 in this state. When the valve 60 is pressed forward, the blocking step 58 of the valve holding member 50 and the blocking slope 65 of the valve 60 separate from each other, allowing the ink 11D to flow between them.
[0037] As described above, the ink 11D that can flow between the valve holding member 50 and the valve 60 passes between the inner circumferential surface of the rear accommodation portion 41D (FIG. 8F) and the cylindrical portion 31 (FIG. 11G) of the flow path resistance valve 30. Furthermore, the ink 11D flows between the tip surface of the cylindrical portion 31 and the rear end surface of the bottom plate 41A (FIG. 8F) of the valve insertion member 41 through the liquid passage groove 34 (FIG. 11G), and reaches the writing tip 14 through the peripheral groove 23A (FIG. 12D). That is, even if the pressure inside the ink accommodation portion 11C increases, the ink 11D receives flow resistance due to the narrow gap of the liquid passage groove 34 located between the tip surface of the cylindrical portion 31 and the rear end surface of the bottom plate 41A of the valve insertion member 41. This prevents the ink 11D from dripping from the writing tip 14.
[0038] Then, when the pressure applied to the side surface of the barrel 11 is released, it returns to the state shown in Fig. 4. Fig. 18 shows the state at this time in the XVIII-XVIII cross section. When the pressure on the barrel 11 is released, the internal pressure of the ink containing section 11C drops rapidly, and the negative pressure causes air to flow from the outside into the valve 60 in an amount equal to the amount of ink 11D consumed. The pressure of this air causes the diaphragm 62D of the valve 60 to protrude backward. At this time, air flows into the ink containing section 11C through the ventilation gap 80 generated between the rigid portion 61 and the elastic portion 62. [Industrial Applicability]
[0039] INDUSTRIAL APPLICABILITY The present invention can be used in a writing instrument that has a valve mechanism inside a barrel and supplies ink by pressing the barrel. [Explanation of symbols]
[0040] 10 Writing instruments 11 Axle tube 11A Large diameter section 11B Small diameter section 11C Ink storage section 11D Ink 12 front shaft 12A covering portion 12B outer periphery locking portion 12C Tapered section 12D Front insertion hole 12E Rear insertion hole 13 Cap 13A Inner circumference locking portion 13B Step 13C Rib 14 Writing tip 14A Brush tip 14B Flange 15 Front shaft insert 15A Front part 15B Rear part 16 O-ring 20 brush tip holding member 21 insertion portion 22 abutment plate 23 through hole 23A peripheral groove 24 front receiving portion 30 flow resistance valve 31 cylindrical portion 32 insertion portion 33 protrusion 34 liquid passage groove 35 notch 40 Valve mechanism 41 Valve insertion member 41A Bottom plate 41B Cylindrical portion 41C Valve insertion hole 41D Rear housing section 42 Spring 50 Valve retaining member 51: leading edge; 52: receiving tube portion; 53: connecting piece 54 crown portion 55 first inlet hole 56 receiving hole 58 Blocking step 60 Valve 61 Rigid part 62 Elastic portion 62A Belt portion 62B Annular portion 62C Connection 62D Diaphragm 63 Fluid passage tube 64 Intermediate band 65 Blocking slope 66 Ventilator 67A Exposed part 67B Covered part 69A Secondary flow hole 69B Vent hole
Claims
1. an ink container having an internal space for storing ink, the ink container being deformable when a side surface of the ink container is pressed; A writing tip formed as a brush tip made of bundled fibers; A tip barrel into which the writing tip is inserted and which is attached to the tip of the barrel; a valve mechanism that is housed in the tip portion of the barrel and opens when a side surface of the barrel is pressed; a valve insertion member including: a bottom plate located at the tip edge of the valve mechanism and having a valve insertion hole formed at its axis; and a tubular portion inserted into the tip side of the valve mechanism and having a rear accommodation portion formed in its internal space; a flow path resistance valve including: a columnar portion that is accommodated in the rear accommodation portion and has a tip surface that contacts a rear end surface of the bottom plate of the valve insertion member; and an insertion portion that protrudes from the tip surface of the columnar portion and is inserted into the valve insertion hole; In addition to providing The valve mechanism includes: a valve retaining member fixed to the barrel; a valve inserted into the valve holding member and movable in a forward and backward direction; a spring that is inserted into the valve and interposed between the valve and a rear end surface of the flow path resistance valve, and that constantly biases the valve rearward with respect to the valve holding member, A writing implement, wherein a liquid passage groove recessed rearward is formed in a part of a tip surface of the cylindrical portion of the flow path resistance valve.
2. a tip insert that is inserted into the tip of the tip barrel with the writing tip inserted therein and has a tip edge exposed from the tip of the tip barrel; a brush tip holding member that is inserted into the front barrel insert and holds the writing tip while the insertion portion of the flow path resistance valve is inserted and held at the axis center and an abutment plate formed at the rear end of the front barrel insert is abutted against the rear end of the front barrel insert; The pen further includes a cap that covers the tip of the front barrel and has a plurality of ribs provided therein, the rear ends of which are stepped. The writing instrument according to claim 1 , wherein a step of the rib presses a tip of the front barrel insert rearward when the cap is attached to the front barrel.