Ballpoint pen

Abstract

To facilitate drawing a special writing line.SOLUTION: A ball point pen comprises: a transfer ball 21 capable of rolling on a surface P subject to writing; a cylindrical tip body 22 rotatably holding the transfer ball 21 in an exposed state; and an ink supply part 25 for supplying an ink from a rear side to an outer peripheral surface of the transfer ball 21 in the tip body 22. The outer peripheral surface of the transfer ball 21 is disposed with a recess to transfer to the surface P subject to writing. An ink to be transferred to the surface P subject to writing becomes a special writing line L having a dark portion, a rubbed portion, a thick portion, a thin portion or the like, in other words, the writing line L appearing like much more drawn by a crayon.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a ballpoint pen in which ink is transferred by rolling a transfer ball on a writing surface. [Background technology]

[0002] Conventional inventions of this type include, for example, an aqueous ballpoint pen that includes a transfer ball that rolls on the writing surface, a tip that rotatably holds the transfer ball, a barrel connected to the rear side of the tip, an ink absorbing body that holds ink within the barrel, and a relay core that is connected to the ink absorbing body and extends forward, with its front end in contact with the tip, as described in Patent Document 1. When the transfer ball is pushed backward by the writing pressure during writing, the intermediate core is elastically deformed, forming a minute gap between the transfer ball and the inner surface of the crimped part of the tip. Therefore, the ink adhering to the outer surface of the transfer ball is ejected to the outside through the gap and transferred from the outer surface of the transfer ball to the surface being written on. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 64-025180 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the conventional ballpoint pens described above can produce lines of uniform width for a long period of time without smearing, etc. On the other hand, they cannot intentionally vary the line width or cause the lines to smear, and may not be suitable for drawing pictures or patterns. [Means for solving the problem]

[0005] In view of the above problems, the present invention has the following configuration. The ink cartridge includes a transfer ball that can roll on a writing surface, a cylindrical tip body that rotatably holds the transfer ball in an exposed state, and an ink supply unit that supplies ink to an outer peripheral surface of the transfer ball from the rear side within the tip body, The outer circumferential surface of the transfer ball is provided with a recess so that the transfer ball can be transferred to the writing surface. And, Within the tip body, an ink relay core that supplies ink to the transfer ball from the rear side, a receiving member that can advance and retreat relative to the ink relay core and receive the transfer ball from the rear side, and a biasing member that biases the receiving member forward are provided, The ink transfer core is positioned with a gap between it and the transfer ball, and comes into contact with the transfer ball when the transfer ball and the receiving member are moved back against the biasing force of the biasing member due to writing pressure. A ballpoint pen characterized by Effect of the Invention

[0006] Since the present invention is configured as described above, it is possible to draw special lines, such as faded lines and lines of varying thickness. [Brief description of the drawings]

[0007] [Figure 1] 1 is a full cross-sectional view showing an example of a ballpoint pen according to the present invention. [Diagram 2] FIG. 2 is an exploded perspective view showing the ballpoint pen with the center core unit removed. [Diagram 3] FIG. [Figure 4] 1A is an enlarged full cross-sectional view of the main part of the ballpoint pen when no writing pressure is applied, and FIG. 1B is an enlarged full cross-sectional view of the main part when writing pressure is applied. [Diagram 5] 1 is an enlarged image showing an example of a line drawn with the same ballpoint pen. [Figure 6] FIG. 11 is a perspective view showing another example of the transfer ball. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] This embodiment discloses the following features. The first feature is that it comprises a transfer ball capable of rolling on the surface to be written on, a cylindrical tip body that holds the transfer ball in an exposed state so that it can rotate freely, and an ink supply section within the tip body that supplies ink to the outer surface of the transfer ball from the rear side, and a recess is provided on the outer surface of the transfer ball so that it can be transferred to the surface to be written on (see Figures 1 to 6).

[0009] A second feature is that the recesses are a large number of minute recesses, and the surface roughness of the outer circumferential surface of the transfer ball is within the range of Ra 0.1 to 10 μm due to the large number of minute recesses.

[0010] As a third feature, the transfer ball is made of a synthetic resin material and has a diameter within a range of φ1.0 to φ15 mm.

[0011] A fourth feature is that the viscosity of the ink is within the range of 2 to 20 mPa·s.

[0012] As a fifth feature, the ink supply unit includes an ink relay core made of a fiber bundle so as to be adjacent to the transfer ball (see FIG. 4(a)).

[0013] As a sixth feature, the tip body is provided with an ink relay core that supplies ink to the transfer ball from the rear side, a receiving member that can advance and retreat relative to the ink relay core and receive the transfer ball from the rear side, and a biasing member that biases the receiving member forward, the ink relay core is positioned with a gap between it and the transfer ball, and comes into contact with the transfer ball when the transfer ball and the receiving member retreat against the biasing force of the biasing member due to pen pressure (see Figures 4(a) and (b)).

[0014] <Specific embodiment> Next, specific embodiments having the above-mentioned features will be described in detail with reference to the drawings.

[0015] In this specification, the barrel axis direction means the direction along the barrel centerline, and the barrel circumferential direction means the direction around the barrel centerline. In addition, "front" means one side of the barrel axis direction in which the transfer ball protrudes, and "rear" means the opposite side to the one side. In addition, in this specification, the radial direction of the barrel means the diameter direction of the barrel perpendicular to the center line of the barrel, the outer radial direction of the barrel means the direction away from the center of the barrel along the radial direction of the barrel, and the inner radial direction of the barrel means the direction toward the center of the barrel along the radial direction of the barrel.

[0016] This ballpoint pen 1 is a retractable ballpoint pen comprising a barrel 10, a core unit 20 housed in the barrel 10 so as to be movable back and forth a predetermined distance, and a retractable operation mechanism 30 for moving the core unit 20 forward to lock the transfer ball 21 in a state where it protrudes from the barrel 10, or for releasing this locked state to retract the transfer ball 21 into the barrel 10.

[0017] The barrel 10 is formed into a long cylinder extending in the front-rear direction from one or more cylindrical members. The barrel 10 in the illustrated example includes a front axle 11 having an opening at the front end, and a rear axle 12 that is screwed to the rear end of the front axle 11 and extends rearward.

[0018] An engaging portion 11a for engaging the front end portion of the second biasing member 31 is provided on the inner circumferential surface of the front shaft 11. The engaging portion 11a is a stepped portion whose diameter is reduced toward the front.

[0019] On the inner peripheral surface of the rear axle 12, guide grooves, cam slopes, and the like (not shown) that engage with the rotor 32 and knock rod 33 of the projection / retraction operation mechanism 30 are provided.

[0020] The core unit 20 integrally comprises a transfer ball 21 capable of rolling on the writing surface P, a roughly cylindrical tip body 22 which holds the transfer ball 21 in an exposed, rotatable manner, a receiving member 23 which receives the transfer ball 21 from the rear side, a first biasing member 24 which biases the receiving member 23 forward, and an ink supply section 25 which receives the receiving member 23 from the rear side and supplies ink to the outer peripheral surface of the transfer ball 21 from the rear side within the tip body 22. This core unit 20 is detachable from the barrel 10 and can be replaced, and is sometimes called a ballpoint pen refill or the like.

[0021] The transfer ball 21 is a sphere made of a synthetic resin material. The diameter of the transfer ball 21 is set within a range of φ1.0 to 15 mm, and more preferably within a range of φ2 to 6 mm. A large number of minute recesses are formed on the outer peripheral surface of this transfer ball 21 so as to be transferred to the writing surface P, and due to these large number of minute recesses, the surface roughness of the outer peripheral surface of the transfer ball 21 is within the range of Ra 0.1 to 10 μm. According to the illustrated preferred example, the transfer ball 21 has a diameter of φ4 mm and a surface roughness of 3 μm.

[0022] The tip body 22 is formed in a long, generally cylindrical shape with an opening, and a ball house 22a that rotatably holds the transfer ball 21 is formed on the tip side. The ball house 22a has an inner diameter that gradually narrows toward the front, and its front end is formed to be smaller than the outer diameter of the transfer ball 21. The inner edge of this front end contacts the front half side of the outer circumferential surface of the transfer ball 21. The inner peripheral surface of ball house 22a on the rear side of the front end portion is a surface that is free of irregularities, projections, steps, and the like.

[0023] The receiving member 23 is a cylindrical member that moves forward and backward a predetermined distance along the inner circumferential surface of the tip body 22, and its front end annularly receives the rear half of the transfer ball 21. This receiving member 23 can move forward and backward relative to the ink relay core 25a inserted inside.

[0024] The transfer ball 21, the chip body 22, and the receiving member 23 are made of a hard resin material having excellent abrasion resistance, such as polyacetal resin (POM). As another example, the transfer ball 21, the chip body 22, and the receiving member 23 may be made partly or entirely of a metal material.

[0025] The first biasing member 24 is a compression coil spring, and biases the receiving member 23 forward. The first biasing member 24 is fitted in an annular shape to the front end side of the tubular connecting member 25b so as to surround the periphery of the ink relay core 25a in an annular shape. The first biasing member 24 has a front end in contact with the rear end of the receiving member 23, and has a rear end engaged with the tubular connecting member 25b.

[0026] The ink supply section 25 integrally comprises an ink relay core 25a adjacent to the chip body 22 from the rear side, a tubular connecting member 25b inserted into and connected to the chip body 22, an ink storage core 25c that stores ink to be supplied to the ink relay core 25a, and a tubular case 25d that cylindrically covers the ink storage core 25c.

[0027] The ink relay core 25a is a fiber bundle made of a large number of synthetic fibers in the shape of a long shaft. The front end side of the ink relay core 25a is formed in a tapered bullet shape. A gap s is provided between the front end of the ink relay core 25a and the transfer ball 21. This gap s narrows when the transfer ball 21 retracts (see FIG. 4). The ink relay core 25a penetrates the cylindrical connecting member 25b in the front-rear direction. The rear end of the ink relay core 25a is press-fitted into the front end of the ink storage core 25c.

[0028] The tubular connection member 25b is made of a hard synthetic resin material (e.g., polypropylene resin (PP)) and is formed in a generally cylindrical shape extending in the front-rear direction. The tubular connection member 25b holds the ink relay core 25a inserted therethrough, and receives the receiving member 23 from the rear side at its front end when the receiving member 23 is retracted.

[0029] More specifically, an annular projection 25b1 (see FIG. 4) is provided on the inner peripheral surface of the cylindrical connection member 25b, which is pressed against the outer peripheral surface of the ink relay core 25a to hold the ink relay core 25a immovably.

[0030] Further, a first locking portion 25b2 that receives the rear end portion of the first biasing member 24 and a second locking portion 25b3 that receives the rear end portion of the second biasing member 31 are provided on the outer circumferential surface of the cylindrical connection member 25b. The first locking portion 25b2 is a stepped portion formed in an annular shape on the outer circumferential surface of the tubular connection member 25b. The second locking portion 25b3 is an annular projection that protrudes radially outward from the rear end side of the outer circumferential surface of the cylindrical connection member 25b.

[0031] The rear half side of the cylindrical connecting member 25b configured as described above (more specifically, between the first engaging portion 25b2 and the second engaging portion 25b3) is press-fitted into the inner circumferential surface of the tip body 22 and is integrated with the tip body 22.

[0032] The ink reservoir core 25c is a thin-walled synthetic resin cylinder containing a number of synthetic fibers, which are impregnated with ink, and is sometimes called a wadding. The viscosity of the ink is set within the range of 2 to 20 mPa·s. The ink in the ink storage core 25c flows to the ink relay core 25a by capillary force.

[0033] The cylindrical case 25d is formed in a long, bottomed cylindrical shape with the rear end at the bottom. The cylindrical case 25d covers the ink storage wick 25c over its entire length and is attached in a ring shape to the cylindrical connecting portion 25b4 at the rear end side of the cylindrical connecting member 25b.

[0034] The retractable operating mechanism 30 comprises a second biasing member 31 which biases the core unit 20 rearward, a rotor 32 which moves back and forth and rotates behind the core unit 20, and a knock rod 33 which moves back and forth behind the rotor 32. When the knock rod 33 is pushed forward, the rotor 32 and the core unit 20 etc. move forward and rotate to engage with an engaging portion (not shown) on the inner surface of the shaft tube 10, and when the knock rod 33 is pushed forward again, the engaged state is released and the rotor 32 and the core unit 20 etc. are moved backward. For these, for example, the structure described in JP 2018-149787 A can be applied.

[0035] The second biasing member 31 is a compression coil spring that fits annularly around the tip body 22, with its front end engaged with the shaft tube 10 and its rear end engaged with the cylindrical connecting member 25b, biasing the center core unit 20 backward. The biasing force of the second biasing member 31 is greater than the biasing force of the first biasing member 24.

[0036] Next, the characteristic functions and effects of the ballpoint pen 1 having the above configuration will be described in detail. 1, the tip end of the tip body 22 and the transfer ball 21 are located inside the barrel 10. When the knock bar 33 is pushed forward, the rotor 32 and the core unit 20 move forward against the biasing force of the second biasing member 31, and the tip end of the tip body 22 and the transfer ball 21 protrude forward of the barrel 10, and the rotor 32 is locked in this protruding state.

[0037] When no writing pressure is applied to the transfer ball 21, as shown in FIG. 4(a), a gap s is secured between the transfer ball 21 and the ink relay core 25a.

[0038] When writing pressure is applied to the transfer ball 21, as shown in Figure 4 (b), the transfer ball 21 and the receiving member 23 move back against the biasing force of the first biasing member 24, the transfer ball 21 is pressed against the front end of the ink relay core 25a, and ink flows from the ink relay core 25a to the outer peripheral surface of the transfer ball 21. As the transfer ball 21 rotates, the ink adhering to the outer peripheral surface of the transfer ball 21 exits the tip body 22 through the gap between the transfer ball 21 and the front end of the ball house 22a, and is transferred from the outer peripheral surface of the transfer ball 21 to a writing surface P such as paper.

[0039] During this transfer, the transfer ball 21 has, due to the numerous minute recesses on its outer circumferential surface, some parts that are pressed strongly against the writing surface P, some parts that are pressed weakly, some parts that are pressed over a wide area, and some parts that are pressed over a narrow area. As a result, the ink transferred to the writing surface P becomes a special writing line L having dark areas, faded areas, thick areas, thin areas, etc., in other words, a writing line L that looks like a crayon (see Figure 5).

[0040] Thereafter, when the transfer ball 21 is pulled away from the writing surface P and the writing pressure is released, the transfer ball 21 and the receiving member 23 move forward due to the biasing force of the first biasing member 24, and the front half of the transfer ball 21 is pressed against the inward edge of the front end of the ball house 22a, forming a gap s between the transfer ball 21 and the ink relay core 25a that prevents the flow of ink (see Figure 4(a)).

[0041] This can reduce the dripping phenomenon in which ink excessively flows out from the front end of tip body 22.

[0042] Furthermore, when the ink has run out, the rear shaft 12 can be removed from the front shaft 11 and the center core unit 20 can be easily replaced (see FIG. 2).

[0043] <Modification> According to the above embodiment, the outer peripheral surface of the transfer ball 21 is processed to have a predetermined surface roughness, thereby forming a large number of recesses on the outer peripheral surface of the transfer ball 21. As another example, it is also possible to form the recesses using letters, figures, patterns, etc. The transfer ball 21' shown in FIG. 6 has a plurality of recesses 21a arranged in a regular hexagonal pattern on its outer circumferential surface, and has an appearance similar to that of a soccer ball. In the ballpoint pen 1, if the transfer ball 21 is replaced with a transfer ball 21', a special writing line can be drawn by the plurality of recesses 21a.

[0044] Furthermore, according to the above embodiment, ink is supplied to the transfer ball 21 from the ink relay core 25a and the ink storage core 25c, but as another example, it is also possible to construct the ink relay core 25a and the ink storage core 25c integrally from a fiber bundle.

[0045] Furthermore, according to the above embodiment, a retractable ballpoint pen is configured, but the structure of the core unit 20 can also be applied to ballpoint pens that are not retractable, such as capped ballpoint pens.

[0046] The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the gist of the present invention. [Explanation of symbols]

[0047] 1: Ballpoint pen 10: Shaft tube 20: Core unit 21,21': Transfer ball 21a: Recess 22: Chip body 23: Supporting member 24: First biasing member 25: Ink supply unit 25a: Ink cartridge 25b: Cylindrical connecting member 25c: Ink reservoir 25d: Cylindrical case 30: Appearance operation mechanism P: Writing surface

Claims

1. The ink cartridge includes a transfer ball that can roll on a writing surface, a cylindrical tip body that rotatably holds the transfer ball in an exposed state, and an ink supply unit that supplies ink to an outer peripheral surface of the transfer ball from the rear side within the tip body, The transfer ball has an outer peripheral surface provided with a recess so as to be transferred to a writing surface, Within the tip body, an ink relay core that supplies ink to the transfer ball from the rear side, a receiving member that can advance and retreat relative to the ink relay core and receive the transfer ball from the rear side, and a biasing member that biases the receiving member forward are provided, The ink relay core is positioned with a gap between it and the transfer ball, and comes into contact with the transfer ball when the transfer ball and the receiving member retract against the biasing force of the biasing member due to writing pressure.

2. 2. The ballpoint pen according to claim 1, wherein the recesses are a large number of minute recesses, and the surface roughness of the outer peripheral surface of the transfer ball is within a range of Ra 0.1 to 10 μm due to the large number of minute recesses.

3. 3. The ballpoint pen according to claim 1, wherein the transfer ball is made of a synthetic resin material and has a diameter within a range of φ1.0 to φ15 mm.

4. 4. The ballpoint pen according to claim 1, wherein the ink supply section includes an ink relay core made of a fiber bundle in close proximity to the transfer ball.

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