Notebook

Abstract

To provide a writing instrument capable of preventing backlash of a writing body without the need to attach parts to the writing body.SOLUTION: Provided is a writing instrument that allows a writing body to move forward and backward in an axial direction by means of an operation portion and a knock spring provided in a barrel. A holding member having a slit formed in the axial direction is provided on the tip side of the barrel. In a state in which the writing portion at the tip of the writing body protrudes from the tip of the barrel, the circumference of the slit forming portion is reduced in diameter by the pressure of the knock spring, and the holding member holds the writing portion at the tip of the writing body.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a writing instrument such as a knock-type ballpoint pen or a mechanical pencil, in which a writing element can be protruded from and retracted from the tip of a barrel. [Background technology]

[0002] In knock-type writing instruments, a small gap is formed between the writing part and the barrel to ensure smooth sliding. If the gap causes the writing body to rattle during writing, it can hinder comfortable writing.

[0003] Regarding such rattle prevention technology, Patent Document 1 proposes a writing instrument in which an anti-rattle member (zipper member) is integrally arranged on the refill (writing body) side to suppress rattle in the writing part (ballpoint pen tip) of a monochrome ballpoint pen. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-216015 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the conventional techniques described above require the attachment of a rattle prevention member to the writing element side of the refill, etc., which is inconvenient.

[0006] SUMMARY OF THE INVENTION In view of the above circumstances, the present invention aims to provide a writing implement that can prevent rattle of the writing body without the need to attach any parts to the writing body. [Means for solving the problem]

[0007] The present invention is a writing instrument in which the writing body can be moved back and forth in the axial direction by an operating part and a knock spring provided on the barrel, and characterized in that a holding member having a slit formed in the axial direction is provided on the tip side of the barrel, and when the writing part at the tip of the writing body protrudes from the tip of the barrel, the periphery of the slit forming part is reduced in diameter by the pressure of the knock spring, and the holding member holds the writing part at the tip of the writing body.

[0008] In the present invention, it is preferable that the knock spring has a small diameter portion formed thereon that is smaller in diameter than the outer diameter portion.

[0009] In the present invention, it is preferable that an inclined surface is formed on the inner surface of the tip of the barrel, and an inclined portion is formed on the outer periphery of the tip of the holding member, and as the holding member moves forward due to the knock spring, the inclined portion comes into contact with the inclined surface on the inner surface of the tip, causing the inner surface of the holding member to engage with the outer surface of the writing part.

[0010] In the present invention, it is preferable that the knock spring has a small diameter portion in the axial center portion, and that the small diameter portion presses the rear end portion of the retaining member forward, thereby moving the retaining member forward.

[0011] In the present invention, it is preferable that the holding member is made of a viscoelastic material and has a slit formed in the axial direction on the outer periphery on the tip side.

[0012] In the present invention, the knock spring has a double structure with a small diameter portion inside the outer diameter portion, and it is preferable that the small diameter portion of the knock spring presses against the rear end of the holding member, causing the holding member to deform and engage with the writing portion at the tip of the writing element.

[0013] In the present invention, it is preferable that a retaining member that protrudes rearward from the inner surface of the tip of the barrel is formed integrally with the barrel, and that the retaining member is deformed inwardly by the small diameter portion of the knock spring, making it possible to hold the writing part at the tip of the writing element. [Effects of the Invention]

[0014] According to the writing instrument of the present invention, when the writing part at the tip of the writing body protrudes from the tip of the barrel, the pressure of the knock spring causes the periphery of the slit forming part to shrink in diameter, and the holding member holds the writing part at the tip of the writing body, thereby achieving the excellent effect of preventing the writing body from rattling without the need to attach any parts to the writing body. [Brief explanation of the drawings]

[0015] [Figure 1] 1A and 1B are explanatory diagrams of a writing instrument according to a first embodiment of the present invention in a non-knocking state, in which (a) is a front view, (b) is a side view rotated 90° from (a), (c) is a vertical cross-sectional view along line CC in (a), and (d) is an enlarged cross-sectional view of the tip portion. [Figure 2] 1 is an explanatory diagram of the writing instrument in a knocked state, in which (a) is a front view, (b) is a side view rotated 90° from (a), (c) is a longitudinal cross-sectional view along line CC in (a), and (d) is an enlarged cross-sectional view of the tip. [Figure 3] Parts diagrams of the holding member of the writing instrument, where (a) is a perspective view from the front, (b) is a front view, (c) is a view from one side, (d) is a side view rotated 90° from (c), (e) is a vertical cross-sectional view of (c) along line EE, (f) is a view from the other side, (g) is a perspective view from the rear, and (h) is a rear view. [Figure 4] 10A and 10B are part drawings of the knock spring of the writing instrument, in which FIG. 10A is a side view and FIG. 10B is a perspective view from the front. [Figure 5] These are component diagrams of the tip portion (tip barrel) of the writing instrument, where (a) is a perspective view from the front, (b) is a front view, (c) is a side view, (d) is a vertical cross-sectional view of (c) taken along line DD, (e) is a perspective view from the rear, and (f) is a rear view. [Figure 6] 10A and 10B are explanatory diagrams of a writing instrument according to a second embodiment of the present invention in a non-knocking state, in which (a) is a front view, (b) is a side view rotated 90° from (a), (c) is a vertical cross-sectional view along line CC in (a), and (d) is an enlarged cross-sectional view of the tip portion. [Figure 7]1 is an explanatory diagram of the writing instrument in a knocked state, in which (a) is a front view, (b) is a side view rotated 90° from (a), (c) is a longitudinal cross-sectional view along line CC in (a), and (d) is an enlarged cross-sectional view of the tip. [Figure 8] The parts diagrams show the holding member of the writing instrument, where (a) is a perspective view from the front, (b) is a front view, (c) is a view from one side, (d) is a side view rotated 90 degrees from (c), (e) is a vertical cross-sectional view taken along the line EE of (c), (f) is a perspective view from the rear, and (g) is a rear view. [Figure 9] 10A and 10B are part drawings of the knock spring of the writing instrument, in which FIG. 10A is a side view and FIG. 10B is a perspective view from the front. [Figure 10] 10A to 10C are explanatory views of a writing implement according to a third embodiment of the present invention in a non-knocking state, where (a) is a front view, (b) is a vertical cross-sectional view, and (c) is an enlarged cross-sectional view of the tip portion. [Figure 11] 10A to 10C are explanatory diagrams of the writing implement in a knocked state, in which (a) is a front view, (b) is a vertical cross-sectional view, and (c) is an enlarged cross-sectional view of the tip portion. [Figure 12] The parts diagrams show the tip of the writing instrument, with (a) being a front view, (b) being a rear view, (c) being a side view rotated 90° from (a), (d) being a front view, (e) being a vertical cross-sectional view taken along line EE of (a), (f) being a cross-sectional view of the tip, and (g) being a cross-sectional perspective view of the tip. [Figure 13] 10A and 10B are component diagrams of the knock spring of the writing instrument, in which FIG. 10A is a perspective view from the front, and FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0017] [First embodiment] The writing instrument according to the first embodiment will be described with reference to Figs. 1 to 5. Fig. 1 shows the writing instrument in a non-knocking state, and Fig. 2 shows the writing instrument in a knocking state. Fig. 3 shows the retaining member, Fig. 4 shows the knock spring, and Fig. 5 shows the tip portion (tip barrel) of the writing instrument.

[0018] As shown in FIGS. 1 and 2, the writing implement is a writing implement in which a writing body 16 can be moved back and forth in the axial direction by an operating portion 12 and a knock spring 14 provided in a barrel 10.

[0019] The writing instrument has a retaining member 18 at the tip of the barrel 10, which has a plurality of grooves, so-called slits 18a..., formed in the axial direction. When the writing part 20 at the tip of the writing body 16 protrudes from the opening 22a of the tip end portion (front barrel) 22 at the tip of the barrel 10, the pressure of the knock spring 14 causes the periphery of the front part 18f, which is the slit forming part, to contract in diameter, and the retaining member engages with and holds the outer surface of the writing part 20 at the tip of the writing body 16.

[0020] In addition, an inclined surface 22b is formed on the inner surface of the tip end portion 22 of the barrel 10 at the tip end, and an inclined portion 18d is formed on the outer periphery of the tip end portion of the holding member 18.When in the knock state, as the holding member 18 moves forward due to the knock spring 14, the inclined portion 18d comes into contact with the inclined surface 22b on the inner surface of the tip end portion 22, and the inner surface 18b of the holding member 18 engages with the outer surface of the writing part 20.

[0021] In addition, the knock spring 14 has a small diameter portion 14b in the center in the axial direction, and as shown in Figure 2, in the knock state, the small diameter portion 14b presses the rear end portion of the retaining member 18 forward, causing the retaining member 18 to move forward.

[0022] Each part will be explained in detail. [Shaft tube 10] As shown in Figure 1, barrel 10 is generally cylindrical overall, with a tip section (also called the "front barrel") 22 fixed to its front end. Tip section 22 is fixed to the front end of barrel 10 by threading a male thread 10a formed on the outer periphery of the front end of barrel 10 with a female thread 22c on the inner periphery of the rear end of tip section 22. A non-slip grip cover 24 made of an elastic resin material such as elastomer is fitted over the outer periphery of the barrel 10 behind thread 10a. Barrel 10 and rear barrel 26 are made of hard resin.

[0023] [Rear shaft 26] A roughly cylindrical main body 26b of the rear axle 26 is attached from behind to the rear of the axle tube 10. The unevenness on the outer peripheral surface of the front part of the main body 26b engages with the unevenness on the inner peripheral surface of the axle tube 10, fixing the axle tube 10 to the rear axle 26. A clip 26a for hanging on a pocket or the like is integrally molded with the main body 26b on the outer periphery of the rear part of the rear axle 26 so as to contact the outer periphery of the rear part of the axle tube 10.

[0024] The operating unit 12 is disposed so as to protrude rearward from the rear end opening of the rear axle 26. Within the rear portion of the rear axle 26, the operating unit 12 is a knock mechanism that is made up of an engagement portion 12a that engages with the rear axle 26, a cover portion 12b that covers the engagement portion 12a, and a spring that urges the cover portion 12b rearward. The knock mechanism may be the well-known Kern knock type or various other knock mechanisms.

[0025] [Cursive 16] The writing element 16 is mounted in the barrel 10 so as to be movable back and forth, and has a writing part 20 at the tip and an ink tube 28 at the rear connected by a joint 30.

[0026] The writing element 16 is a refill in which the writing part 20, ink tube (ink storage part) 28 and joint 30 are integrated, and when the ink tube 28 runs out of ink, it can be replaced with a new refill.

[0027] The writing unit 20 is a ballpoint pen tip with a writing ball 20b fitted at the tip of a cylindrical body 20a, and a spring 20c for pressing the writing ball is attached inside the cylindrical body 20a. Each part of the writing unit 20 can be made of metal or resin.

[0028] The ink tube 28 contains ink, and its rear end abuts against the front end of the operation unit 12 .

[0029] The joint 30 has a front portion 30a that is a single cylinder, into which the writing head 20 is mounted and fixed, and a rear portion 30b that is a double cylinder, into which the ink tube 28 is attached and fixed. The rear portion 30b has a diameter that is larger than that of the front portion 30a, starting from a stepped portion 30b'. As shown in Figures 1 and 2, the rear end of the knock spring 14 abuts against the stepped portion 30b', and the knock spring 14 urges the writing element 16 rearward.

[0030] [Holding member 18] 3, the holding member 18 has a front portion 18f and a rear portion 18r whose diameter increases at the boundary of the annular protrusion 18c, and is generally cylindrical overall. The front portion 18f forms a slit-forming portion having three (in multiple examples) slits 18a... cut in the axial direction from the tip side to the vicinity of the central protrusion 18c.

[0031] The outer periphery of the tip of front portion 18f is formed with a chamfered slope 18d. The tip of front portion 18g has a portion that protrudes inward corresponding to slope 18d, and when front portion 18f contracts in diameter, inner surface 18b of the protruding portion engages with the outer surface of writing element 20 (see Figure 2).

[0032] [Knock Spring 14] 1, 2, and 4, the knock spring 14 has a small diameter portion 14b that is smaller in diameter than the outer diameter portion 14a. The knock spring 14 has a large-diameter outer diameter portion 14a at its front and rear axial portions, and a central portion sandwiched between the large-diameter outer diameter portion 14a that forms the small diameter portion 14b, which has a smaller winding diameter than the outer diameter portion 14a. The knock spring 14 is formed by winding an elastic wire material such as metal having the same diameter, and the outer diameter portion 14a has a longer axial winding length and a lower winding density than the small diameter portion 14b.

[0033] [Mouth part 22] The tip portion 22 is fixed to the tip side of the barrel 10 and is integrated with the barrel 10 to form the tip portion.

[0034] As shown in detail in FIG. 5, the nose portion 22 is hollow and generally cylindrical, and the outer circumferential surface thereof has a warhead shape in which the front portion 22f is tapered more than the rear portion 22r.

[0035] The inner peripheral surface gradually expands in diameter from the opening 22a at the tip to the threaded portion 22c on the inner surface at the rear.

[0036] The tip of the tip portion 22 has an opening 22a that is circular in cross section, and a cavity with a similar circular cross section is formed axially rearward from the opening 22a. The part of the opening where the cavity is formed is called the opening 22a'. The opening 22a' allows the tip of the writing part 20 to appear and disappear from the opening 22a, which allows the writing part 20 to pass through the cavity (see Figure 2).

[0037] 5, the rear end of the opening 22a' expands in diameter in a stepped manner to form an inclined surface 22b that tapers rearward. A plurality of cavities with circular cross sections are formed between the inclined surface 22b and the threaded portion 22c, forming a retaining member sliding portion 22d in which the retaining member 18 is housed and slides, and a spring accommodating portion 22e in which the knock spring 14 is housed (see FIGS. 1, 2, and 5).

[0038] The retaining member sliding portion 22d and the spring accommodating portion 22e are mainly formed inside the front portion 22f of the tip portion 22, with a step 22e' as the boundary. The inside of the retaining member sliding portion 22d is formed so that the rear portion is wider in diameter than the front portion via the step 22d', and the front portion of the step 22d' is shorter than the rear portion. The spring accommodating portion 22e is wider in diameter than the retaining member sliding portion 22 via the step 22e'. An annular rib 22g is formed to protrude inward on the inner periphery of the step 22e' and engages with the protrusion 18c on the outer periphery of the retaining member 18 to prevent the retaining member 18 from coming off in a non-knock state (see FIG. 1).

[0039] As shown in FIGS. 1 and 2, the spring accommodating portion 22e has a function of bringing the front end of the knock spring 14 into contact with the rear surface side of the step 22e'.

[0040] [Operation of the writing instrument of the first embodiment] In the writing instrument, the knock spring 14 is located within the front end and tip portion 22 of the barrel 10.

[0041] 1, when the operating unit 12 is not being knocked, the front end of the knock spring 14 abuts against the step 22e' (rear side) of the spring accommodating portion 22e inside the tip portion 22, while the rear end of the knock spring 14 abuts against the front end surface of the step 30b' of the joint 30 of the writing unit 16. In this state, the knock spring 14 presses the writing unit 16 rearward from the step 30b' via the joint 30 by its elastic force.

[0042] Therefore, in the non-knocking state, the writing implement has the writing body 16 positioned at the rear and the writing part 20 not protruding from the tip opening 22a of the tip part 22 but remaining immersed.

[0043] On the other hand, when the operating part 12 is knocked forward, the writing part 20 at the tip of the writing body 16 protrudes from the opening 22a of the tip part (front barrel) 22 at the tip of the barrel 10, as shown in FIG.

[0044] At this time, because knock spring 14 has small-diameter portion 14b in the axial center, small-diameter portion 14b presses the rear end of holding member 18 forward, causing holding member 18 to move forward. As knock spring 14 moves holding member 18 forward, inclined portion 18d of holding member 18 comes into contact with inclined surface 22b on the inner surface of tip portion 22 at the tip of barrel 10, causing the periphery of front portion 18f, which is the slit-forming portion, to contract in diameter, and inner surface 18b of holding member 18 engages with the outer surface of writing part 20 at the tip of writing element 16, thereby preventing rattling of writing part 20. In other words, when knocking, the contact spring of small-diameter portion 14b in the center of knock spring 14 presses holding member 18 into tip portion 22, thereby engaging writing part 20.

[0045] Therefore, when knocking, the writing part 20 is held by the holding member 18, and vibration of the writing body 16 can be suppressed.

[0046] [Second embodiment] Next, a writing instrument according to a second embodiment will be described with reference to Figures 6 to 9. Figure 6 shows the writing instrument in a non-knocking state, and Figure 7 shows the writing instrument in a knocking state. Figure 8 shows the retaining member, and Figure 9 shows the knock spring. The same reference numerals are used for the same parts as in Figures 1 to 5.

[0047] As shown in FIGS. 6 and 7, the writing implement is a writing implement in which the writing body 16 can be moved back and forth in the axial direction by the operating portion 12 and knock spring 42 provided in the barrel 10.

[0048] A holding member 40 made of a viscoelastic material such as silicone rubber and having a plurality of slits 40a formed on the outer periphery of the tip side of the barrel 10 is provided on the tip side.

[0049] When the writing part 20 at the tip of the writing body 16 protrudes from the tip of the barrel 10, the pressure of the knock spring 42 causes the periphery of the front part 40f, which is the slit forming part, to contract in diameter, and the holding member 40 holds the writing part 20 at the tip of the writing body 16.

[0050] As shown in FIG. 8, the holding member 40 has a plurality of slits 40a formed in the axial direction on the outer periphery of the tip side of the front portion 40f, and a groove portion 40c consisting of a plurality of projections and recesses formed in the inner periphery along the axial direction.

[0051] The rear portion 40r has a flange 40d formed at the rear end of its outer periphery, and the inner periphery of the front portion 40f has a stepped portion 40e that is wider than the inner periphery of the front portion 40f, forming a flat circular cross section. The outer periphery of the tip of the front portion 40f has a chamfered inclined portion 40g.

[0052] As shown in Figures 6, 7, and 9, the knock spring 42 has a double structure with an outer diameter portion 42a located on the radially outer side and a small diameter portion 42b, which is smaller than the outer diameter portion 42a, located on the inner side. The knock spring 42 has the outer diameter portion 42a on the outer side in the axial direction and the small diameter portion 42b on the inner side, with the rear ends 42a', 42b' folded back continuously. The knock spring 14 is formed by continuously winding an elastic wire material such as metal having the same diameter, and the outer diameter portion 42a is configured to have a longer winding length in the axial direction than the small diameter portion 42b.

[0053] As shown in Figure 6, in the non-knock state, the writing body 16 is positioned rearward by the stepping force of the outer diameter portion 42a of the knock spring 42, and the writing part 20 does not protrude from the tip opening 22a of the tip portion 22, but remains submerged.

[0054] On the other hand, when the operating part 12 is knocked forward, the writing part 20 at the tip of the writing body 16 protrudes from the opening 22a of the tip part (front barrel) 22 at the tip of the barrel 10, as shown in FIG.

[0055] At this time, small-diameter portion 42b of knock spring 42 presses the rear end of holding member 40 forward, causing holding member 40 to move forward. As knock spring 42 moves holding member 40 forward, inclined portion 40g of holding member 40 comes into contact with inclined surface 22b on the inner surface of tip portion 22 at the tip of barrel 10, causing the periphery of the slit-forming portion of front portion 40f to elastically deform and contract in diameter, and the inner circumferential surface of front portion 40f tightly engages with the outer surface of writing head 20 at the tip of writing element 16, holding writing head 20 steady. The inner circumferential surface of front portion 40f can easily contract in diameter due to groove portion 40c, allowing for a tight grip on writing head 20.

[0056] As shown in Figure 6, the knock spring 42 is separated from the holding member 40 when not being knocked, and only when knocked on does the small diameter portion 42b press against the holding member 40 and press into the inclined surface 22b of the tip portion 22, deforming the holding member 40 to a small diameter, allowing it to tightly grip and hold the outer surface of the writing head 20. This effectively prevents rattling of the writing head 20 during writing. The softness of the writing feel can be easily adjusted by setting the viscoelastic modulus of the holding member 40.

[0057] [Third embodiment] Next, a writing implement according to a third embodiment will be described with reference to Figures 10 to 13. Figure 10 shows the writing implement in a non-knocking state, and Figure 11 shows it in a knocking state. Figure 12 shows the tip portion, and Figure 13 shows the components of the knock spring. The same reference numerals are used for the same parts as in Figures 1 to 5.

[0058] 10 and 11, the writing implement has a retaining member 46 that protrudes rearward and is integral with the inner surface of the tip portion (front barrel) 44 at the tip of the barrel 10, and the small diameter portion 48b of the knock spring 48 causes the retaining member 46 to deform inwardly, enabling it to hold the writing part 20 at the tip of the writing element 16. Although a spring is omitted within the writing part 20, it is not essential that a spring be provided.

[0059] As shown in Figures 10 to 12, tip portion (front barrel) 44 extends halfway through the entire writing instrument and is fitted and fixed to the tip of barrel 10. Holding member 46, formed to protrude rearward on the inner surface of tip portion 44, has multiple plates protruding rearward, forming slit forming portion 46b with slits 46a... formed between the plates. An inclined portion 46c is formed on the outer peripheral surface of holding member 46 on the rear end side.

[0060] As shown in Figure 13, the knock spring 48 has a large-diameter outer diameter portion 48a at its front and rear axial portions, and a small-diameter portion 48b at its center. The rear portion 48a2 of the outer diameter portion 48a is longer and more densely wound than the front portion 48a1. The small-diameter portion 48b is even more densely wound than the rear portion 48b2.

[0061] In the writing instrument, when in a non-operating state, the writing body 16 is pushed rearward by the knock spring 48, and the writing part 20 is maintained in a retracted state, as shown in FIG.

[0062] On the other hand, when the operating part 12 is knocked forward, the writing part 20 at the tip of the writing body 16 protrudes from the opening 22a of the tip part (front barrel) 22 at the tip of the barrel 10, as shown in FIG.

[0063] At this time, because knock spring 48 has small diameter portion 48b near the center in the axial direction, small diameter portion 48b presses the rear end of holding member 46 forward and abuts against inclined portion 46c, narrowing slit 46a and deforming slit forming portion 46b to reduce its diameter. Holding member 46 engages with the outer surface of writing part 20 at the tip of writing element 16, thereby holding writing part 20 without rattle.

[0064] The above-described embodiments are specific examples of the present invention, but various modifications can be made within the scope of the present invention. The material and hardness of each part can be selected appropriately. [Industrial Applicability]

[0065] The writing implement of the present invention can be used as a knock-type writing implement such as a ballpoint pen or a mechanical pencil. [Explanation of symbols]

[0066] 10 shaft cylinder 12 Control section 14 Knock spring (first embodiment) 14a Outer diameter part 14b Small diameter section 16 Cursive 18 Holding member (first embodiment) 18a Slit 18b Inside 18d Slope 18f front 18r rear 22 Mouth 22a opening 22a' opening 22b Slope 22c threaded part 22d Retaining member sliding portion 22e Spring housing 22f front 22g rib 22r rear 40 Holding member (second embodiment) 40a slit 40c groove 40d flange 40g inclined part 40e Step 40f front 40r rear 42 Knock spring (second embodiment) 42a Outer diameter part 42b Small diameter section 44 Mouth portion (third embodiment) 44a aperture 46 Holding member (third embodiment) 46a Slit 46b Slit forming section 46c Slope 48 Knock spring (third embodiment) 48a Outer diameter 48a1 front 48a2 rear 48b Small diameter section

Claims

1. In a writing instrument in which the writing body can be moved back and forth in the axial direction by an operating part and a knock spring provided in a barrel, A holding member having a slit formed in the axial direction is provided on the tip side of the barrel, When the writing part at the tip of the writing body protrudes from the tip of the barrel, the knock spring presses the rear end of the holding member forward, thereby reducing the diameter of the periphery of the slit-forming part, and the holding member holds the writing part at the tip of the writing body, The knock spring has an outer diameter portion on the outside and a small diameter portion on the inside relative to the axis, and is formed by winding wire of the same diameter.

2. A writing instrument as described in claim 1, characterized in that a retaining member that protrudes rearward from the inner surface of the tip of the barrel is formed integrally with the barrel, and the retaining member is deformed inwardly by the small diameter portion of the knock spring, making it possible to hold the writing part at the tip of the writing body.

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