Pen nibs and fountain pens

Abstract

To provide a pen nib and fountain pen that can suppress ink leakage from the air passage. [Solution] The pen core 30 comprises an ink passage 32 through which ink flows from the ink reservoir 16 to the pen tip 22 when writing, an air passage 34 through which air flows from the outside to the ink reservoir, an outer core 40 having a through hole 42 extending in the axial direction da, and an inner core 50 disposed within the through hole 42. The outer core 40 has a first slit 44 that connects the through hole 42 to the outer peripheral surface 46 of the outer core 40. The inner core 50 has a second slit 52 that extends in the axial direction da and communicates with the first slit 44, a rear groove 54 that extends in the axial direction da, a wall portion 63 located in front of the rear groove 54, and a pocket portion 70 located in front of the wall portion 63 and opening to the rear. The ink passage 32 includes the first slit 44 and the second slit 52, and the air passage 34 includes the rear groove 54, the wall portion 63, and the pocket portion 70.

Description

Technical Field

[0001] The present invention relates to a pen refill and a fountain pen.

Background Art

[0002] A fountain pen generally includes a barrel, a writing member attached to the front end of the barrel, and an ink storage portion disposed in the barrel for storing ink. The writing member includes a pen refill and a pen tip. The writing member has a pen tip for forming a writing stroke and a pen refill for supporting the pen tip. The pen refill has an ink groove for communicating the ink storage portion with the pen tip. In such a fountain pen, due to the capillary force of the ink in the ink groove, the ink stored in the ink storage portion is sent to the pen tip. When writing, if the ink in the ink storage portion decreases and the pressure in the ink storage portion decreases, the capillary force of the ink in the ink groove alone cannot send the ink to the pen tip. Therefore, by providing an air passage different from the ink groove in the pen refill, external air is introduced into the ink storage portion through this air passage during writing, so that the pressure in the ink storage portion does not decrease.

[0003] When sucking ink into the ink storage portion, the ink in the ink bottle is sucked into the ink storage portion using the air passage. In a conventional fountain pen, since the opening of the air passage is immersed in the ink in the ink bottle, it is necessary to immerse almost the entire exposed portion from the barrel of the writing member in the ink. At this time, ink may also adhere to the barrel, and it has been time-consuming to wipe the barrel after sucking the ink. To address such problems, a fountain pen adopting a double pen refill structure including an outer refill having an axially extending through hole and an inner refill disposed in the outer refill is known (see Patent Document 1). In such a fountain pen, since the opening of the air passage is located near the tip of the pen tip, only the vicinity of the tip of the writing member can be immersed in the ink in the ink bottle, and the ink can be sucked into the ink storage portion.

[0004] In fountain pens employing a double-nib structure, the opening of the air passage faces forward in the axial direction, which creates a problem where ink is prone to squirting out of the air passage when the pen is subjected to impact. This problem is particularly pronounced when the fountain pen is dropped with the nib pointing downwards. To address this problem, Patent Document 1 describes a method of suppressing ink squirting out of the air passage by providing a constriction within the air passage. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2017-213767 [Overview of the project] [Problems that the invention aims to solve]

[0006] In fountain pens employing such a double-nib structure, there is a need to further suppress ink leakage from the air passage.

[0007] This invention has been made with these points in mind, and aims to provide a pen nib and fountain pen that can suppress ink leakage from the air passage. [Means for solving the problem]

[0008] The pen nib according to the present invention is [1] The ink passage through which ink flows from the ink reservoir to the pen tip when writing, An air passage through which air flows from the outside toward the ink storage section, An outer core having a through hole extending in the axial direction, A fountain pen nib comprising an inner core disposed within the aforementioned through hole, The outer core has a first slit that connects the through hole and the outer surface of the outer core, The inner core has a second slit extending in the axial direction and communicating with the first slit, a rear groove extending in the axial direction, a wall portion positioned in front of the rear groove, and a pocket portion positioned in front of the wall portion and opening to the rear. The ink passage includes the first slit and the second slit, The air passage is a pen tip, including the rear groove, the wall portion, and the pocket portion.

[0009] The pen nib according to the present invention is [2] The inner core is the pen tip according to [1], having a front groove that extends in the axial direction and is provided adjacent to the pocket portion in the circumferential direction.

[0010] The pen nib according to the present invention is [3] The inner core is the pen core described in [2], having a hole that connects the front end of the pocket portion and the front groove.

[0011] The pen nib according to the present invention is [4] The inner core is positioned circumferentially offset from the rear groove and has a plane that extends parallel to the central axis, The pocket portion and the front groove are provided on the plane and are the pen nib described in [2] or [3].

[0012] The pen nib according to the present invention is [5] The inner core is the pen tip according to any one of [1] to [4], having another pocket portion located in front of the pocket portion.

[0013] The pen nib according to the present invention is [6] The inner core has other pocket portions located in front of the pocket portion, The other pocket portion is a pen tip described in any one of [2] to [4], located in front of the front groove.

[0014] The pen nib according to the present invention is [7] The inner core is Another wall portion disposed in front of the front groove, The pen core according to any one of [2] to [4] and [6], which is located in front of the pocket portion and has another pocket portion that is circumferentially displaced with respect to the front groove.

[0015] The fountain pen according to the present invention, is a fountain pen provided with the pen core according to any one of [1] to [7].

Advantages of the Invention

[0016] According to the present invention, it is possible to provide a pen core and a fountain pen that can suppress the ink from jumping out of the air passage.

Brief Description of the Drawings

[0017] [Figure 1] FIG. 1 is a diagram for explaining a first embodiment according to the present invention, and is an external view showing an example of a fountain pen provided with a pen core. [Figure 2] FIG. 2 is a view of the front portion of the fountain pen of FIG. 1 seen along the arrow with II in FIG. 1 attached. [Figure 3] FIG. 3 is a longitudinal sectional view showing an enlarged front portion of the fountain pen of FIG. 1. [Figure 4] FIG. 4 is a longitudinal sectional view showing an enlarged front portion of the fountain pen of FIG. 1. [Figure 5] FIG. 5 is a longitudinal sectional view showing a pen core. [Figure 6] FIG. 6 is a cross-sectional view corresponding to the VI-VI line of FIG. 5. [Figure 7] FIG. 7 is a cross-sectional view corresponding to the VII-VII line of FIG. 5. [Figure 8] FIG. 8 is a cross-sectional view corresponding to the VIII-VIII line of FIG. 5. [Figure 9] FIG. 9 is a perspective view showing the inner core of the pen core. [Figure 10] FIG. 10 is a view showing the inner core as seen from the outside in the radial direction. [Figure 11]Figure 11 shows the inner core as viewed along the arrow labeled XI in Figure 10. [Figure 12] Figure 12 is a diagram illustrating a second embodiment according to the present invention, and is a longitudinal cross-sectional view showing an enlarged view of the front portion of a fountain pen. [Figure 13] Figure 13 is a magnified longitudinal cross-sectional view of the front portion of a fountain pen. [Figure 14] Figure 14 is a longitudinal cross-sectional view showing the pen tip. [Figure 15] Figure 15 is a perspective view showing the inner core. [Figure 16] Figure 16 shows the inner core as viewed from the radial outside. [Figure 17] Figure 17 shows the inner core as seen along the arrow labeled XVII in Figure 16. [Figure 18] Figure 18 is a diagram illustrating a third embodiment according to the present invention, and is a longitudinal cross-sectional view showing an enlarged front portion of a fountain pen. [Figure 19] Figure 19 is a magnified longitudinal cross-sectional view of the front portion of a fountain pen. [Figure 20] Figure 20 is a longitudinal cross-sectional view showing the pen tip. [Figure 21] Figure 21 is a cross-sectional view corresponding to the line XXI-XXI in Figure 20. [Figure 22] Figure 22 is a perspective view showing the inner core. [Figure 23] Figure 23 shows the inner core as viewed from the radial outside. [Figure 24] Figure 24 shows the inner core as seen along the arrow labeled XXIV in Figure 23. [Figure 25] Figure 25 shows the inner core as viewed along the arrow labeled XXV in Figure 24. [Modes for carrying out the invention]

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that, for the sake of illustration and ease of understanding, the scale and aspect ratios of the drawings accompanying this specification have been appropriately altered and exaggerated from those of the actual objects.

[0019] Furthermore, terms used in this specification to specify shapes, geometric conditions, and their degrees, such as "parallel," "orthogonal," and "identical," as well as values ​​for length and angle, shall not be strictly interpreted, but shall be interpreted to include a range that allows for the expectation of similar functionality.

[0020] In this specification, the direction in which the central axis A of the fountain pen 10 extends (longitudinal direction, vertical direction in the longitudinal section view) is defined as the axial direction da, the direction perpendicular to the axial direction da is defined as the radial direction, and the direction along the circumference around the central axis A is defined as the circumferential direction. Furthermore, along the axial direction da, the side that approaches the writing surface such as paper when writing (the lower side in the longitudinal section view) is defined as the front, and the side that moves away from the writing surface (the upper side in the longitudinal section view) is defined as the rear. Furthermore, along the radial direction, the side that approaches the central axis A is defined as the inside, and the side that moves away from the central axis A is defined as the outside.

[0021] First Embodiment Figure 1 is a diagram illustrating a first embodiment according to the present invention, and is an external view showing an example of a fountain pen 10 equipped with a nib 30. Figure 2 is a view of the front portion of the fountain pen 10 along the arrow labeled II in Figure 1. Figure 3 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10.

[0022] The fountain pen 10 comprises a barrel 12, a connecting member 14, an ink reservoir 16, and a writing member 20. The barrel 12 houses the ink reservoir 16 and is intended to be held by the user's fingers when writing with the fountain pen 10. The barrel 12 extends axially da along the central axis A of the fountain pen 10. Therefore, the central axis of the barrel 12 coincides with the central axis A of the fountain pen 10. In this embodiment, the barrel 12 has a substantially cylindrical shape. The barrel 12 may be composed of a single part or of multiple parts.

[0023] The connecting member 14 is a member that connects the barrel 12 and the writing member 20 (see Figure 3). The connecting member 14 has a substantially cylindrical shape. The central axis of the connecting member 14 coincides with the central axis A of the fountain pen 10. The writing member 20 is attached to the barrel 12 by attaching the writing member 20 to the connecting member 14, and the connecting member 14 being attached to the barrel 12. The method of attaching the writing member 20 to the connecting member 14 and the method of attaching the connecting member 14 to the 20 are not particularly limited. For example, the writing member 20 may be attached to the connecting member 14 by press-fitting. Alternatively, for example, the connecting member 14 may be attached to the barrel 12 by screwing the male threaded portion on the outer surface of the connecting member 14 into the female threaded portion on the inner surface of the barrel 12. The connecting member 14 may be omitted. In this case, the writing member 20 may be attached directly to the barrel 12.

[0024] The ink storage section 16 has the function of storing ink. In this embodiment, the ink storage section 16 may be a converter or a cartridge. The converter has the function of creating a negative pressure inside the ink storage section 16 and drawing up ink from the outside through an air passage 34, which will be described later. The ink storage section 16 is attached to the rear end of the connecting member 14. For example, the ink storage section 16 may be attached to the connecting member 14 by press-fitting the rear end of the connecting member 14 into the front end of the ink storage section 16.

[0025] The writing component 20 has a pen tip 22 and a pen feed 30. The pen tip 22 is a component that contacts a writing surface such as paper and forms a line on the writing surface. The pen tip 22 has a pen point 24 and a slit 26. The pen point 24 is located at the tip of the pen tip 22 and is the part that contacts the writing surface when writing. The slit 26 is a slit that extends linearly backward from the pen tip 22. Ink that flows from the ink passage 32 of the pen feed 30 (described later) to the pen tip 22 is supplied to the pen point 24 through the slit 26.

[0026] The nib 30 of this embodiment will be described with reference to Figures 3 to 11. Figure 3 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10. Figure 4 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10. Figure 5 is a longitudinal cross-sectional view showing the nib 30. Figure 6 is a transverse cross-sectional view corresponding to line VI-VI in Figure 5. Figure 7 is a transverse cross-sectional view corresponding to line VII-VII in Figure 5. Figure 8 is a transverse cross-sectional view corresponding to line VIII-VIII in Figure 5. Figure 9 is a perspective view showing the inner core 50 of the nib 30. Figure 10 is a diagram showing the inner core 50 viewed from the radial outside. Figure 11 is a diagram showing the inner core 50 viewed along the arrow labeled XI in Figure 10. Note that in Figure 3, each component of the fountain pen 10 is hatched, and in Figure 4, the ink 80 inside the fountain pen 10 is hatched.

[0027] The pen nib 30 supports the pen tip 22 and is a component that allows the ink 80 in the ink reservoir 16 to flow to the pen tip 22. The pen tip 22 is attached to the outer surface of the pen nib 30. The writing member 20 is attached to the connecting member 14 by attaching the rear end of the pen nib 30 to the front end of the connecting member 14. The pen nib 30 has an ink passage 32 and an air passage 34. The ink passage 32 is a passage through which the ink 80 flows from the ink reservoir 16 to the pen tip 22 when writing. The air passage 34 is a passage through which air flows from the outside to the ink reservoir 16.

[0028] The pen tip 30 of this embodiment has an outer core 40 and an inner core 50. The outer core 40 has a through hole 42 extending in the axial direction da. The inner core 50 is disposed within the through hole 42 of the outer core 40 and is a rod-shaped member as a whole. The entire inner core 50 may be disposed within the through hole 42, or only a part of the inner core 50 may be disposed within the through hole 42.

[0029] The outer core 40 further has a first slit 44 and comb grooves 48. The first slit 44 is a passage that connects the through hole 42 and the outer circumferential surface 46 of the outer core 40. The first slit 44 extends linearly along the axial direction da. The first slit 44 communicates with the slit 26 of the pen tip 22. The comb grooves 48 are a plurality of grooves that extend in the circumferential direction and are arranged along the axial direction da. The comb grooves 48 communicate with the first slit 44 via the outer circumferential surface 46. When the air in the ink reservoir 16 expands due to changes in temperature and / or atmospheric pressure, the amount of ink that has expanded may be pushed out of the ink reservoir 16 into the ink passage 32. The comb grooves 48 have the function of suppressing ink from dripping from the fountain pen 10 by holding the ink that has been pushed out into the ink passage 32 in the comb grooves 48 via the outer circumferential surface 46 from the first slit 44.

[0030] The inner core 50 has a second slit 52, a rear groove 54, a wall portion (first wall portion) 63, and a pocket portion (first pocket portion) 70. The second slit 52 is a groove formed on the outer circumferential surface of the inner core 50. The second slit 52 extends in the axial direction da and communicates with the first slit 44 of the outer core 40. The rear end of the second slit 52 also communicates with the ink storage portion 16. Therefore, the ink storage portion 16 and the first slit 44 communicate with each other via the second slit 52. In this embodiment, the ink passage 32 includes the first slit 44 and the second slit 52. The ink 80 stored in the ink storage portion 16 can flow towards the pen point 24 through the second slit 52, the first slit 44, and the cutout 26.

[0031] The rear groove 54 extends linearly along the axial direction da. The rear end of the rear groove 54 communicates with the ink storage section 16. The rear groove 54 is positioned circumferentially offset from the second slit 52. In particular, the rear groove 54 may be positioned circumferentially offset by 180 degrees from the second slit 52.

[0032] The wall portion (first wall portion) 63 is positioned in front of the rear groove 54. The first wall portion 63 has the function of obstructing the flow of ink 80 toward the front within the rear groove 54 and guiding the ink 80 to the pocket portion (first pocket portion) 70. In this embodiment, the first wall portion 63 extends perpendicular to the axial direction da. That is, the first wall portion 63 is a wall portion that extends in the circumferential and radial directions. However, it is not limited to this, and the first wall portion 63 may extend in a direction inclined with respect to the axial direction da and the circumferential direction. For example, the first wall portion 63 may extend in a direction inclined with respect to the axial direction da and the circumferential direction such that it moves away from the rear groove 54 as it moves toward the front. In this case, the angle between the first wall portion 63 and the circumferential direction may be 45 degrees or less. The angle between the first wall portion 63 and the circumferential direction is the smaller of the two angles formed between the direction in which the first wall portion 63 extends and the circumferential direction.

[0033] A circumferential groove (first circumferential groove) 56 is formed along the first wall portion 63. In this embodiment, the first circumferential groove 56 extends perpendicular to the axial direction da. That is, the first circumferential groove 56 extends in the circumferential direction. If the first wall portion 63 extends in a direction inclined with respect to the axial direction da and the circumferential direction, the first circumferential groove 56 may also extend in a direction inclined with respect to the axial direction da and the circumferential direction.

[0034] The pocket portion (first pocket portion) 70 has the function of temporarily containing at least a portion of the ink 80 moving forward through the air passage 34. The first pocket portion 70 is located in front of the first wall portion 63 and opens to the rear. The first pocket portion 70 is positioned circumferentially offset from the rear groove 54. In particular, the first pocket portion 70 may be positioned circumferentially offset by about 180 degrees from the rear groove 54. The first pocket portion 70 is formed to extend along the axial direction da. The front end of the first pocket portion 70 is closed. In this embodiment, the air passage 34 includes the rear groove 54, the wall portion (first wall portion) 63, the circumferential groove (first circumferential groove) 56, the pocket portion (first pocket portion) 70, and the front groove (first front groove) 60. At least a portion of the ink 80, which moves forward within the rear groove 54 and is guided by the first wall portion 63 to move circumferentially within the first circumferential groove 56, enters the first pocket portion 70 from the rear. As a result, the ink 80 is contained within the first pocket portion 70, and it is prevented from splashing out of the air passage 34.

[0035] In this embodiment, the inner core 50 has a front groove (first front groove) 60. The first front groove 60 extends in the axial direction da and is provided adjacent to the first pocket portion 70 in the circumferential direction. In this embodiment, the front end of the first front groove 60 is open to the outside. A side wall (first side wall) 71 is provided between the first pocket portion 70 and the first front groove 60. The first side wall 71 prevents the ink 80 contained in the first pocket portion 70 from moving to the first front groove 60. The first side wall 71 extends in the axial direction da. The first side wall 71 separates the first pocket portion 70 and the first front groove 60.

[0036] A hole (first hole) 73 is formed between the front end of the first pocket portion 70 and the first front groove 60. The first hole 73 is a through hole (through groove) that penetrates the first side wall 71 in the circumferential direction. As a result, the first pocket portion 70 and the first front groove 60 are in communication via the first side wall 71. The first hole 73 has the function of allowing air inside the first pocket portion 70 to flow into the first front groove 60 when ink 80 enters the first pocket portion 70 from the rear. Because the inner core 50 has the first hole 73, air inside the first pocket portion 70 can escape into the first front groove 60, allowing ink 80 to enter the first pocket portion 70 smoothly.

[0037] The inner core 50 has a plane (first plane) 67 that is positioned circumferentially offset from the rear groove 54 and extends parallel to the central axis A. In this embodiment, the first plane 67 is positioned circumferentially offset by 180 degrees from the rear groove 54. Also, in this embodiment, as shown in Figures 9 and 10, the first pocket portion 70 and the first front groove 60 are provided on the same first plane 67. As a result, the first pocket portion 70 is provided on the first plane 67 on which the first front groove 60 is provided, so the first pocket portion 70 can be formed with a simple structure.

[0038] When drawing the ink 80 into the ink reservoir 16, the fountain pen 10 is held so that the writing member 20 faces downwards, and the writing member 20 is immersed in the ink in the ink bottle. At this time, the front end opening of the air passage 34 is immersed in the ink. In this state, the ink reservoir (converter) 16 is operated to create a negative pressure inside the ink reservoir 16, thereby drawing the ink from the ink bottle into the ink reservoir 16 via the air passage 34. Specifically, the ink in the ink bottle passes through the first front groove 60, the first circumferential groove 56, and the rear groove 54 in order towards the ink reservoir 16. At this time, since the front end opening of the air passage 34 is located near the tip of the nib (pen point 24), only the area near the tip of the writing member 20 is immersed in the ink in the ink bottle, and the ink can be drawn into the ink reservoir 16. Therefore, it is possible to suppress ink from adhering to the barrel 12.

[0039] When writing with the fountain pen 10, the pen point 24 of the nib 22 is brought into contact with the writing surface, such as paper, and moved along the writing surface. This causes the ink held in the pen point 24 to adhere to the writing surface, forming a line. When the ink in the nib 22 is consumed, ink is supplied from the ink reservoir 16 to the nib 22 through the ink passage 32. This ink supply is mainly achieved by the action of capillary force in the ink passage 32.

[0040] When the fountain pen 10 is subjected to an impact, particularly when it is subjected to a forward impact such as falling with the nib 22 pointing downwards, the ink 80 can move forward through the air passage 34. In the fountain pen 10 of this embodiment, the ink 80 that has moved forward through the rear groove 54 first collides with the first wall portion 63. This reduces the momentum of the ink 80. After that, the ink 80 flows along the first wall portion 63 through the first circumferential groove 56, and when the first wall portion 63 is interrupted, it proceeds forward through the air passage 34. Here, the first pocket portion 70 is located in front of the part where the first wall portion 63 is interrupted. Therefore, at least a portion of the ink 80 that has moved through the first circumferential groove 56 enters the first pocket portion 70 from the rear. At this time, since the first hole 73 is formed in the front end portion of the first side wall 71, the air inside the first pocket portion 70 escapes through the first hole 73 to the first front groove 60. As a result, the ink 80 enters the first pocket portion 70 smoothly. The ink 80 that has advanced forward in the air passage 34 is contained in the first pocket portion 70, which effectively prevents the ink 80 from splashing out of the front end opening of the air passage 34.

[0041] The pen nib 30 of this embodiment is a pen nib 30 for a fountain pen 10, comprising an ink passage 32 through which ink flows from the ink reservoir 16 to the pen tip 22 when writing, an air passage 34 through which air flows from the outside to the ink reservoir 16, an outer core 40 having a through hole 42 extending in the axial direction da, and an inner core 50 disposed within the through hole 42, wherein the outer core 40 has a first slit that connects the through hole 42 and the outer peripheral surface 46 of the outer core 40 The inner core 50 has a 44, and the inner core 50 has a second slit 52 that extends in the axial direction da and communicates with the first slit 44, a rear groove 54 that extends in the axial direction da, a wall portion 63 located in front of the rear groove 54, and a pocket portion 70 located in front of the wall portion 63 and opening to the rear. The ink passage 32 includes the first slit 44 and the second slit 52, and the air passage 34 includes the rear groove 54, the wall portion 63, and the pocket portion 70.

[0042] The fountain pen 10 of this embodiment is equipped with the aforementioned nib 30.

[0043] When the fountain pen 10 is subjected to an impact, especially when it is subjected to a forward impact such as when it falls with the nib 22 pointing downwards, the ink 80 may move forward through the air passage 34, and there is a risk that the ink may spill out to the outside from the front end opening of the air passage 34. With the nib 30 and fountain pen 10 of this embodiment, at least a portion of the ink 80 moving forward within the air passage 34 is contained within the pocket portion 70. This effectively prevents the ink 80 from spilling out to the outside from the front end opening of the air passage 34.

[0044] In the pen tip 30 of this embodiment, the inner core 50 has a front groove 60 that extends in the axial direction da and is provided adjacent to the pocket portion 70 in the circumferential direction.

[0045] In the pen tip 30 of this embodiment, the inner core 50 has a hole 73 that connects the front end of the pocket portion 70 and the front groove 60.

[0046] With this type of pen nib 30, air inside the pocket portion 70 can escape to the front groove 60 through the hole portion 73, allowing ink 80 to enter the pocket portion 70 smoothly.

[0047] In the pen tip 30 of this embodiment, the inner core 50 is positioned circumferentially offset from the rear groove 54 and has a plane 67 that extends parallel to the central axis A, and the pocket portion 70 and the front groove 60 are provided on the plane 67.

[0048] With such a pen tip 30, the pocket portion 70 is provided on the plane 67 where the front groove 60 is provided, so the pocket portion 70 can be formed with a simple structure.

[0049] Second Embodiment A second embodiment of the present invention will be described with reference to Figures 12 to 17. In the following description and the drawings used therein, parts that can be configured in the same way as in the first embodiment will be given the same reference numerals as those used in the description of the first embodiment, and redundant explanations will be omitted.

[0050] Figure 12 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10 in the second embodiment. Figure 13 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10. Figure 14 is a longitudinal cross-sectional view showing the nib 30. Figure 15 is a perspective view showing the inner core 50. Figure 16 is a view of the inner core 50 seen from the radial outside. Figure 17 is a view of the inner core 50 seen along the arrow labeled XVII in Figure 16. Note that in Figure 13, each component of the fountain pen 10 is hatched, and in Figure 14, the ink 80 inside the fountain pen 10 is hatched.

[0051] The inner core 50 of this embodiment has another pocket portion (second pocket portion) 75. The second pocket portion 75 is located in front of the first pocket portion 70. Like the first pocket portion 70, the second pocket portion 75 has the function of temporarily containing at least a portion of the ink 80 moving forward through the air passage 34. The second pocket portion 75 is formed to extend along the axial direction da. The front end of the second pocket portion 75 is closed, and the rear end is open to the rear.

[0052] In this embodiment, the second pocket portion 75 is located in front of the first front groove 60. The rear end of the second pocket portion 75 is connected to the front end of the first front groove 60. In other words, the second pocket portion 75 is formed continuously with the first front groove 60 and is located in front of the first front groove 60 in the axial direction da. Also, when viewed from the axial direction da, the first front groove 60 and the second pocket portion 75 overlap each other.

[0053] In this embodiment, the inner core 50 has another front groove (second front groove) 61. The second front groove 61 extends in the axial direction da and is provided adjacent to the second pocket portion 75 in the circumferential direction. In this embodiment, the front end of the second front groove 61 is open to the outside. Another side wall (second side wall) 77 is provided between the second pocket portion 75 and the second front groove 61. The second side wall 77 prevents the ink 80 contained in the second pocket portion 75 from moving to the second front groove 61. The second side wall 77 extends in the axial direction da. The second side wall 77 separates the second pocket portion 75 and the second front groove 61.

[0054] A second hole (second hole) 79 is formed between the front end of the second pocket portion 75 and the second front groove 61. The second hole 79 is a through hole (through groove) that penetrates the second side wall 77 in the circumferential direction. As a result, the second pocket portion 75 and the second front groove 61 are in communication via the second side wall 77. The second hole 79 has the function of allowing air inside the second pocket portion 75 to flow into the second front groove 61 when ink 80 enters the second pocket portion 75 from the rear. Because the inner core 50 has the second hole 79, air inside the second pocket portion 75 can escape to the second front groove 61, allowing ink 80 to enter the second pocket portion 75 smoothly.

[0055] In this embodiment, as shown in Figures 15 and 16, the first pocket portion 70, the first front groove 60, the second pocket portion 75, and the second front groove 61 are provided on the same first plane 67. This allows the first pocket portion 70 and the second pocket portion 75 to be formed with a simple structure.

[0056] In this embodiment, the air passage 34 includes a rear groove 54, a wall portion (first wall portion) 63, a circumferential groove (first circumferential groove) 56, a pocket portion (first pocket portion) 70, a front groove (first front groove) 60, another pocket portion (second pocket portion) 75, and another front groove (second front groove) 61.

[0057] In the fountain pen 10 of this embodiment, the ink 80 that moves forward through the rear groove 54 first collides with the first wall portion 63. This reduces the momentum of the ink 80. After that, the ink 80 flows along the first wall portion 63 through the first circumferential groove 56, and where the first wall portion 63 ends, it proceeds forward through the air passage 34. At least a portion of the ink 80 that has traveled through the first circumferential groove 56 enters the first pocket portion 70 from the rear. As a result, the ink 80 is contained within the first pocket portion 70. The ink 80 that is not contained within the first pocket portion 70 moves forward through the first front groove 60. At least a portion of the ink 80 that has moved forward through the first front groove 60 enters the second pocket portion 75 from the rear. As a result, the ink 80 is contained within the second pocket portion 75. This further suppresses the ink 80 from flying out of the air passage 34.

[0058] In the pen tip 30 of this embodiment, the inner tip 50 has another pocket portion 75 located in front of the pocket portion 70.

[0059] With this type of pen tip 30, at least a portion of the ink 80 that is not contained in the pocket portion 70 is contained in the other pocket portion 75. This makes it possible to more effectively suppress the ink 80 from spilling out of the front end opening of the air passage 34.

[0060] In the pen tip 30 of this embodiment, the inner tip 50 has another pocket portion 75 located in front of the pocket portion 70, and the other pocket portion 75 is located in front of the front groove 60.

[0061] With this type of pen tip 30, ink 80 that is not contained in the pocket portion 70 and flows into the front groove 60 can be smoothly guided into the other pocket portions 75. Therefore, ink 80 that is not contained in the pocket portion 70 can be properly contained in the other pocket portions 75.

[0062] Third Embodiment A third embodiment of the present invention will be described with reference to Figures 18 to 25. In the following description and the drawings used therein, parts that can be configured in the same way as in the first and second embodiments will be given the same reference numerals as those used in the descriptions of the first and second embodiments, and redundant explanations will be omitted.

[0063] Figure 18 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10 in the third embodiment. Figure 19 is a magnified longitudinal cross-sectional view showing the front portion of the fountain pen 10. Figure 20 is a longitudinal cross-sectional view showing the nib 30. Figure 21 is a perspective view showing the inner core 50. Figure 22 is a transverse cross-sectional view corresponding to the line XXII-XXII in Figure 21. Figure 23 is a view of the inner core 50 seen from the radial outside. Figure 24 is a view of the inner core 50 seen along the arrow labeled XXIV in Figure 23. Figure 25 is a view of the inner core 50 seen along the arrow labeled XXV in Figure 24. Note that in Figure 18, each component of the fountain pen 10 is hatched, and in Figure 19, the ink 80 inside the fountain pen 10 is hatched.

[0064] The inner core 50 of this embodiment has another wall portion (second wall portion) 65 and another pocket portion (second pocket portion) 75. The second wall portion 65 is positioned in front of the first front groove 60. The second wall portion 65 has the function of obstructing the flow of ink 80 toward the front within the first front groove 60 and guiding the ink 80 to the other pocket portion (second pocket portion) 75. In this embodiment, the second wall portion 65 extends perpendicular to the axial direction da. That is, the second wall portion 65 is a wall portion that extends in the circumferential and radial directions. However, it is not limited to this, and the second wall portion 65 may extend in a direction inclined with respect to the axial direction da and the circumferential direction. For example, the second wall portion 65 may extend in a direction inclined with respect to the axial direction da and the circumferential direction such that it moves away from the first front groove 60 as it moves toward the front. In this case, the angle between the second wall portion 65 and the circumferential direction may be 45 degrees or less. The angle between the second wall portion 65 and the circumferential direction is the smaller of the two angles formed between the direction in which the second wall portion 65 extends and the circumferential direction.

[0065] Along the second wall portion 65, another circumferential groove (second circumferential groove) 58 is formed. In this embodiment, the second circumferential groove 58 extends perpendicular to the axial direction da. That is, the second circumferential groove 58 extends in the circumferential direction. If the second wall portion 65 extends in a direction inclined with respect to the axial direction da and the circumferential direction, the second circumferential groove 58 may also extend in a direction inclined with respect to the axial direction da and the circumferential direction.

[0066] The second pocket portion 75 is located in front of the first pocket portion 70. Like the first pocket portion 70, the second pocket portion 75 has the function of temporarily containing at least a portion of the ink 80 moving forward through the air passage 34. The second pocket portion 75 is formed to extend along the axial direction da. The front end of the second pocket portion 75 is closed, and the rear end is open to the rear. In this embodiment, the second pocket portion 75 is positioned circumferentially offset from the first front groove 60. In particular, the second pocket portion 75 may be positioned circumferentially offset by about 180 degrees from the first front groove 60.

[0067] In this embodiment, the inner core 50 has another front groove (second front groove) 61. The second front groove 61 extends in the axial direction da and is provided adjacent to the second pocket portion 75 in the circumferential direction. In this embodiment, the front end of the second front groove 61 is open to the outside. Another side wall (second side wall) 77 is provided between the second pocket portion 75 and the second front groove 61. The second side wall 77 prevents the ink 80 contained in the second pocket portion 75 from moving to the second front groove 61. The second side wall 77 extends in the axial direction da. The second side wall 77 separates the second pocket portion 75 and the second front groove 61.

[0068] A second hole (second hole) 79 is formed between the front end of the second pocket portion 75 and the second front groove 61. The second hole 79 is a through hole (through groove) that penetrates the second side wall 77 in the circumferential direction. As a result, the second pocket portion 75 and the second front groove 61 are in communication via the second side wall 77. The second hole 79 has the function of allowing air inside the second pocket portion 75 to flow into the second front groove 61 when ink 80 enters the second pocket portion 75 from the rear. Because the inner core 50 has the second hole 79, air inside the second pocket portion 75 can escape to the second front groove 61, allowing ink 80 to enter the second pocket portion 75 smoothly.

[0069] The inner core 50 has another plane (second plane) 69 that is positioned circumferentially offset from the first plane 67 and extends parallel to the central axis A. In this embodiment, the second plane 69 is positioned circumferentially offset by 180 degrees from the first plane 67. Also, in this embodiment, as shown in Figure 25, the second pocket portion 75 and the second front groove 61 are provided on the same second plane 69. As a result, the second pocket portion 75 is provided on the second plane 69 on which the second front groove 61 is provided, so the second pocket portion 75 can be formed with a simple structure.

[0070] In this embodiment, the air passage 34 includes a rear groove 54, a wall portion (first wall portion) 63, a circumferential groove (first circumferential groove) 56, a pocket portion (first pocket portion) 70, a front groove (first front groove) 60, another wall portion (second wall portion) 65, another circumferential groove (second circumferential groove) 58, another pocket portion (second pocket portion) 75, and another front groove (second front groove) 61.

[0071] In the fountain pen 10 of this embodiment, the ink 80 that moves forward through the rear groove 54 first collides with the first wall portion 63. This reduces the momentum of the ink 80. After that, the ink 80 flows along the first wall portion 63 through the first circumferential groove 56, and when the first wall portion 63 ends, it proceeds forward through the air passage 34. At least a portion of the ink 80 that has proceeded through the first circumferential groove 56 enters the first pocket portion 70 from the rear. As a result, the ink 80 is contained within the first pocket portion 70. The ink 80 that is not contained within the first pocket portion 70 proceeds forward through the first front groove 60 and collides with the second wall portion 65. This further reduces the momentum of the ink 80. After that, the ink 80 flows along the second wall portion 65 through the second circumferential groove 58, and when the second wall portion 65 ends, it proceeds forward through the air passage 34. At least a portion of the ink 80 that has traveled through the second circumferential groove 58 enters the second pocket section 75 from the rear. As a result, the ink 80 is contained within the second pocket section 75. This further suppresses the ink 80 from spilling out of the air passage 34.

[0072] In the pen tip 30 of this embodiment, the inner core 50 has another wall portion 65 positioned in front of the front groove 60, and another pocket portion 75 that is positioned in front of the pocket portion 70 and offset in the circumferential direction relative to the front groove 60.

[0073] With this type of pen tip 30, at least a portion of the ink 80 that is not contained in the pocket portion 70 is contained in the other pocket portion 75. This makes it possible to more effectively suppress the ink 80 from spilling out of the front end opening of the air passage 34.

[0074] Furthermore, with this type of pen tip 30, any ink 80 that is not contained within the first pocket portion 70 travels forward through the first front groove 60 and collides with the second wall portion 65. This further reduces the forward momentum of the ink 80. Therefore, it is possible to more effectively suppress the ink 80 from flying out of the front end opening of the air passage 34. [Explanation of Symbols]

[0075] 10 fountain pens 12 shaft cylinder 14 Connecting Members 16 Ink reservoir 20 Writing components 22 nibs 24 Pen Point 26 Cutting 30 Pen nibs 32 Ink passage 34 Air passage 40 Outer core 42 Through hole 44. First Slit 46 Outer surface 48 Comb groove 50 inner core 52. Second Slit 54 Posterior groove 56 Circumferential groove (1st circumferential groove) 58 Other circumferential grooves (second circumferential grooves) 60 Front groove (first front groove) 61 Other anterior grooves (second anterior groove) 63 Wall section (First wall section) 65 Other wall sections (second wall section) 67 Plane (1st plane) 69 Other planes (second plane) 70 Pocket section (1st pocket section) 71 Side wall (first side wall) 73 Hole (1st hole) 75 Other pocket section (second pocket section) 77 Other side walls (second side wall) 79 Other holes (second hole) 80 ink A Center axis da axis direction

Claims

1. The ink passage through which ink flows from the ink reservoir to the pen tip when writing, An air passage through which air flows from the outside toward the ink storage section, An outer core having a through hole extending in the axial direction, A fountain pen nib comprising an inner core disposed within the aforementioned through hole, The outer core has a first slit that connects the through hole and the outer surface of the outer core, The inner core has a second slit extending in the axial direction and communicating with the first slit, a rear groove extending in the axial direction, a wall portion positioned in front of the rear groove, and a pocket portion positioned in front of the wall portion and opening to the rear. The ink passage includes the first slit and the second slit, The air passage includes the rear groove, the wall portion, and the pocket portion, and is a pen nib.

2. The pen tip according to claim 1, wherein the inner core extends in the axial direction and has a front groove provided adjacent to the pocket portion in the circumferential direction.

3. The pen tip according to claim 2, wherein the inner core has a hole that connects the front end of the pocket portion and the front groove.

4. The inner core is positioned circumferentially offset from the rear groove and has a plane extending parallel to the central axis. The pen tip according to claim 2, wherein the pocket portion and the front groove are provided on the plane.

5. The pen tip according to claim 1, wherein the inner core has another pocket portion located in front of the pocket portion.

6. The inner core has other pocket portions located in front of the aforementioned pocket portion, The pen tip according to claim 2, wherein the other pocket portion is located in front of the front groove.

7. The aforementioned inner core is The other wall portion located in front of the aforementioned front groove, The pen tip according to claim 2, further comprising another pocket portion located forward of the aforementioned pocket portion and offset circumferentially from the front groove.

8. A fountain pen having the nib described in any one of claims 1 to 7.

Images