JP2012245749A - Writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem such that the leakage of ink in a cap caused by the touching of a pen point with a cap inner wall at mounting the cap that occurs owing to the radial inclination or bending progress of the pen point, and that the pen point drying at the cap mounting that occurs owing to the ink outflow from cap inside at the cap removing or the drying of ink adhered to the closely inserted part of the cap with shaft tube.SOLUTION: In the writing utensil which is configured such that the ink is accommodated in the shaft tube, with the pen point consisting of fiber or porous material used for the ink discharge part fixed to the inner surface of tip opening where the air circulation groove of shaft tube is formed, and with the writing part of pen point projected from the tip opening of shaft tube, the tip opening inner surface of shaft tube is provided with a pen point pressing projection for performing the press-fixing of pen point outer surface in the tip opening inner surface of shaft tube to partition the backward part becoming the side fixed to the pen point pressing projection and the forward part becoming the side for forming a writing portion in the pen point, and is provided with a step part for locking the pen point to the shaft tube in contact with the tip portion of the pen point pressing projection of shaft tube.

Description

  The present invention accommodates ink in a shaft cylinder of a writing instrument, and a pen tip made of a fiber or a porous body serving as an ink discharge portion is used to change the pressure in the shaft cylinder, which changes with the ink discharge of the shaft cylinder. The present invention relates to a writing instrument that is fixed to the inner surface of the tip opening portion formed with an air flow groove for taking air into the shaft tube for adjustment, and the writing portion of the pen tip protrudes from the tip opening portion of the shaft tube.

  In order to obtain a stable handwriting in writing, it is necessary to suppress as much as possible the vibration and shaking of the pen tip caused by the load applied to the pen tip received from the writing surface while the pen tip is held on the writing tube.

  In general writing, the writing tool is inclined and pressed against the writing surface, and the pen tip is used in a state where a load from the writing surface is received. At this time, since the writing instrument is tilted, the side of the pen tip comes into contact with the writing surface from the tip, and the load applied to the pen tip from the writing surface is not only from the tip of the pen tip in the axial direction. In addition, the one in the radial direction from the side portion of the pen tip is also added. Therefore, in order to suppress the vibration and shaking of the pen tip caused by the load on the pen tip received from the writing surface and to obtain a stable handwriting in writing, for example, a step is provided behind the pen tip, The pen tip is held in contact with the stepped portion to be held, and the pen tip is held in the shaft tube in the axial direction, and a plurality of projecting portions in the axial direction are provided on the inner surface of the tip opening of the shaft tube. There is known a technique (Patent Document 1) in which a pen tip is held on a shaft cylinder in a radial direction so as to be pressure-bonded to the side portion.

JP 2009-920 A

In the invention described in Patent Document 1, since a plurality of projections in the axial direction are provided on the inner surface of the tip opening of the shaft tube, vibrations and shaking of the pen tip in the radial direction can be reduced. Since the locking portion between the shaft cylinder and the pen tip is formed behind the protrusion, the radial load received by the pen tip from the writing surface is a plurality of protrusions with the locking portion as a fulcrum. Will be added in the direction of. For this reason, at least a gap serving as an air flow groove is formed between the plurality of protrusions, so that pens to the gap formed between the protrusions are repeatedly used due to repeated use or excessive writing pressure. Tip deformation occurs, and the entire nib is inclined in the radial direction or bent. Even if the entire nib is tilted or bent in the radial direction, the pen nib is not vibrated or shaken, and the stable handwriting is not significantly impaired.
However, if the tip of the pen tip is inclined or bent, the inner wall surface of the cap and the pen tip come into contact with the cap when the cap is mounted. The ink is discharged from the nib due to adhesion to the cap and the capillary force generated in the slight gap formed between the contact part and non-contact part between the inner wall surface of the cap and the nib. Ink leakage occurs inside, and when the cap is removed, the outflow of ink from the inside of the cap and the drying of the ink adhering to the tightly fitting portion between the cap and the shaft tube impairs the sealing between the cap and the shaft tube. There was a problem that the nib was dried and could not be used.
In addition, in the case of pressure bonding so as to cover the entire side of the pen nib, because there is no air circulation groove for taking in the air to adjust the pressure in the shaft cylinder, which changes with the ejection of the ink, Although it is possible to make the air intake means different, in this case, the air intake port cannot be blocked by the cap, so that the ink in the shaft cylinder evaporates and decreases, New problems such as changes in physical properties will occur.

  According to the present invention, ink is accommodated in a shaft cylinder, and a nib made of a fiber or a porous body serving as an ink discharge portion is fixed to an inner surface of a tip opening portion where an air flow groove of the shaft cylinder is formed. The writing part is projected from the tip opening part of the shaft tube, and a pen point crimping convex part for crimping and fixing the outer surface of the pen point is provided on the inner surface of the tip opening part of the shaft tube. The rear part that is fixed to the tip crimping convex part and the front part that forms the writing part are partitioned, and the tip of the pen tip crimping convex part of the shaft cylinder is brought into contact with the tip part to the shaft cylinder. The gist of the writing instrument is provided with a stepped portion to be locked.

Since the position where the shaft tube and the pen tip are locked is ahead of the side portion of the pen tip held by the shaft tube, the deformation of the pen tip caused by the radial load received from the writing surface is reduced. It is performed using the step part which divides the previous rear part and the front part as a fulcrum, and it can suppress adding to the side part of a nib. This prevents the entire pen tip from being deformed, so that the contact between the inner wall surface of the cap and the pen tip when the cap is mounted is suppressed as much as possible. It is possible to suppress drying of the pen tip when the cap is mounted, which is caused by drying of the ink attached to the fitting portion.

The longitudinal cross-sectional view which shows an example. XX sectional drawing of FIG. The longitudinal cross-sectional view which shows another example.

  The writing instrument of the present invention accommodates ink in a shaft cylinder, and a pen tip made of a fiber or a porous body serving as an ink discharge portion is used to change the pressure in the shaft cylinder that changes as the ink is discharged from the shaft cylinder. Any writing instrument that is fixed to the inner surface of the tip opening formed with an air flow groove for taking air into the shaft cylinder for adjustment and the writing portion of the pen tip protrudes from the tip opening of the shaft cylinder can be used. The cylinder may be a so-called raw ink type that stores ink in a free state therein, or a so-called batting type that occludes ink in a fiber converging body. For the raw ink type, there is a valve type with a valve member that can hold the pressure head of the stored ink, and temporarily to prevent ink leakage from the pen tip due to pressure rise inside the shaft cylinder. Used are those that have a temporary ink reservoir for containing ink, or that open the valve member by pressing from the outside, such as a knock, and supply the necessary amount of ink to the occlusion body for ejection from the pen tip it can. In addition, as a batting type, polyethylene terephthalate fiber and polypropylene fiber are bonded with adhesives, fiber converging bodies converged by melting fibers with different melting points, and synthetic resins such as urethane are made porous by elution and elution. It is possible to use an ink occlusion body such as a formed porous body, an aggregate of granular materials in which synthetic resins such as polyethylene terephthalate, polypropylene, and polyethylene are deposited in the form of small spheres or powders.

  The ink contained in the ink tank can be used regardless of water-based ink containing water, oil-based inks containing organic solvents such as isopropyl alcohol, dyes, pigments, or both as colorants. it can. In particular, considering the ink supply property of the nib made of fiber or porous material, the ink viscosity is relatively low such as 1 to 100 mPa · s (B-type viscometer No. 3 rotor, 60 rpm, 25 ° C.). Viscosity is good.

The outer surface of the nib is fixed by pressure to the inner surface of the tip opening of the shaft tube. The inner surface of the tip opening of the shaft tube is reduced in pressure generated in the shaft tube by discharging ink contained in the shaft tube. In order to adjust the pressure to return the state to the original state, any air flow groove that takes in air from outside air into the shaft cylinder may be formed. For example, a plurality of nib crimping convex portions are formed in the axial direction on the inner surface of the tip opening portion of the shaft cylinder, and the gap between each nib crimping projection portion is an air flow groove, or the tip opening of the shaft tube A communicating porous member is arranged as a nib crimping convex portion between the inner surface of the head and the outer surface of the nib without any gap, and the pen is placed on the inner surface of the tip opening of the shaft tube through the communicating porous body. The previous outer surface may be crimped and fixed.

  The nib used for the writing instrument is a fiber converging body obtained by converging polyethylene terephthalate fiber, polyamide fiber, polyacrylonitrile fiber, etc. with an adhesive, etc., and processed into an appropriate shape by grinding and cutting, an olefin resin such as polyethylene, Alternatively, there can be exemplified a sintered body in which a resin containing an elastomer contained in these resins in order to give elasticity to the nib is injection-molded, and then a continuous pore is formed and cured by heat treatment. Also, as the shape of the pen tip, the rear part on the side where the outer surface of the pen tip is crimped and fixed to the inner surface of the tip opening of the shaft tube, and the rear side on which the tip protrudes from the shaft tube and forms the writing part What is necessary is just to make it form the step part divided into the front part whose diameter is larger than a part. In addition, if the angle and shape of the stepped part is divided into a rear part and a front part, and locked against the load at the time of writing received in the axial direction from the tip of the pen tip, if the pen tip can be held, In addition to the vertical shape, it can be set as appropriate depending on the ease of manufacturing the nib, such as a taper shape and an R shape, and the ink supply property at the time of writing. In particular, if the inscribed diameter of the pen tip crimping convex portion of the shaft tube is formed to be 95% or less of the diameter of the front portion of the pen tip, the step of securing the pen tip naturally is ensured. The part can be formed.

The step portion of the tip portion of the pen tip crimping convex portion of the shaft cylinder that is brought into contact with the step portion that divides the rear portion and the front portion of the pen tip is not particularly limited unless the shape does not impair the holding of the pen tip. However, it can be appropriately performed according to the moldability of the shaft tube and the pen tip crimping convex portion, the pen tip insertion property into the shaft tube during assembly, and the like. In addition, since the step portion is formed at the tip portion of the pen tip crimping convex portion of the shaft cylinder, the deformation of the pen tip caused by the radial load received from the writing surface separates the rear portion and the front portion of the pen tip. Since the step portion is used as a fulcrum, deformation of the rear part where the pen tip is crimped to the shaft cylinder in the radial direction is suppressed, and deformation of the entire pen tip is prevented. If the length from the step that divides the tip to the tip of the nib is less than the diameter of the front of the nib, the step that divides the rear and front of the nib, that is, the nib is deformed Since the distance between the fulcrum when doing so and the point of action when trying to deform by the radial load received from the writing surface is as short as possible, deformation of not only the rear part but also the front part can be reduced.

As a cap, when the cap is mounted, the pen tip is covered with the inner surface of the cap in a non-contact state and sealed with the shaft tube to prevent the pen tip from drying, such as ink or ink vapor impregnated in the pen tip. As long as there is no change in shape due to reaction due to swelling, melting, dissolution, decomposition, etc., there are no particular restrictions on the material, polypropylene, polyethylene, polyethylene terephthalate, polyamide, polyethylene naphthalate, polybutylene terephthalate, polyacetal, polycarbonate , Polystyrene, ethylene / vinyl alcohol copolymer, synthetic resin such as polymethacrylate, elastomer injection molding products and metal cutting products, etc., and can be used as appropriate according to the design and application such as transparency and shape of writing instruments.

Hereinafter, an example will be described with reference to the drawings. FIG. 2, which is a cross-sectional view taken along the line XX of FIGS. 1 and 1, is a shaft cylinder, and is an injection molding made of polypropylene having transparency so that the remaining amount of ink 1 from the outside can be visually recognized. In the ink tank 2 formed from the product, a black pigment is dispersed in ethanol, which is the main solvent, and the surface tension is 30.8 mN / m, 3 mPa · s (B-type viscometer No. 3 rotor, 60 rpm , 25 ° C), set to a low viscosity of 25 cc, containing 7 cc of oil-based pigment ink 1 for whiteboard markers in a free state, and opening the valve unit 4 by the knocking of the knocking unit 3, necessary for ejection Ink 1 is injected into the tip of the front shaft 5 formed from a polypropylene injection molded product which is a part of the shaft cylinder, after injection molding of polyethylene containing about 30% elastomer, and then communicated by heat treatment. A so-called knock-type whiteboard marker, in which a writing tip is connected to a pen tip 6 made of a sintered body formed by forming holes and cured with a porosity of 70% and a saturated ink amount of 2.1 cc. It is an example of a writing instrument called. The surface tension of the ink 1 is preferably set to 20 mN / m to 40 mN / m in consideration of penetrability into the pen tip 6, ejection properties, and handwriting bleeding. In this example, ethanol which is the main solvent of ink 1 is not reactive, and taking into account the ink loss from the ink tank 2 and the shaft of the front shaft 5, polypropylene having a relatively low water vapor permeability is used as the ink tank 2 and Although used as the material of the front shaft 5, the material of the ink tank 1 and the front shaft 5 is not particularly limited, and can be appropriately set according to the reactivity of the ink 1 used with the main solvent.
The nib 6 has a front portion 6a with a diameter A of 12.37 mm and a rear portion 6b with a diameter of 11.0 mm. The step 6c is formed so that the nib is divided into the front portion 6a and the rear portion 6b. As shown in FIG. 2 which is a sectional view taken along line XX of FIG. 1, the four protrusions 5 a formed in the axial direction formed on the front shaft 5 are arranged behind the pen tip 6. While the portion 6b is crimped, the step 6c of the pen tip 6 is locked to the tip step 5b of the convex portion 5a, and the pen tip 6 is fixed to the front shaft 5.
Further, the length B from the step 6c of the nib 6 to the tip of the nib 6 is set to 12.0 mm, and the length of the nib 6 protruding from the front end of the front shaft 5 has no trouble in writing. And the distance between the fulcrum and the action point in the deformation when the pen tip 6 is about to be deformed by the radial load applied to the pen tip 6 from the writing surface at the time of writing is made as short as possible. The deformation of the front portion 6a of the pen tip 6 is reduced.
Since the whiteboard marker in this example is used for lectures and meetings with a plurality of opponents, the diameter A of the front portion 6a of the nib 6 is set to 12.37 mm and the handwriting width is set to be easy to see. It is assumed to be relatively large among the writing instruments having a maximum of 12.0 mm. For this reason, the amount of ink 1 discharged from the nib 6 is large, and the same amount of ink 1 as the amount of ink 1 is supplied to the nib 6 again to obtain stable writing followability. The saturated ink amount is 2.1 cc so that sufficient ink 1 can be stored in the tip 6 itself, assuming continuous and continuous writing, etc. Further, the ink 1 is placed in the pen tip 6 behind the pen tip 6, An ink occlusion body 7 that is a polyester fiber converging body and has a saturated ink amount of 2.5 cc, serving as a reserve tank for replenishing and supplying, a front end of a pen tip 6 and a rear part of a front cylinder of a lid 9 described later. The parts 9a are fixed and fixed by being attached. Further, the ink occlusion body 7 is wetter than the nib 6 so that the ink 1 is quickly supplied from the ink occlusion body 7 to the nib 6 as the ink 1 in the nib 6 decreases. Thus, the porosity of the ink occlusion body 7 is set to 98%.
In addition, the means for obtaining stable writing followability is not limited to this example, and the configuration is such that the liquid follows a general natural law that the capillary moves such as capillary wetting from a place where the capillary force is low to a place where it is high. If so, depending on the application and expected writing, etc., the porosity, saturated ink amount, material, type, compression of the ink occlusion body 7 by other molding members and their projections, the nib 6 and the ink occlusion It can be set by an appropriate configuration such as integration of the body 7 and communication of the pen tip 6 and other induction core to the hollow portion of the hollow ink storage body 7. In addition, as a method of manipulating the capillary force such as capillary wetting, in the case of the nib 6 and the porosity and material of the ink occlusion body 7, particularly in the case of the nib 6 made of a sintered body as in this example, an elastomer and a resin are used. In addition to the method based on the material and the blending ratio, for example, modification of capillary wetting by sparse ink treatment of the ink occlusion body 7 using fluorine or silicone powder, and conversely, by the parent ink treatment of the nib 6 using silica powder or the like. Examples include modification of capillary wetting. As an example of a specific method of the parent ink treatment, when the nib 6 of this example is used, first, a polyethylene pellet as a raw material of the nib 6 is dispersed in silica powder with isopropyl alcohol. It is sufficient to immerse the substrate in the substrate, dry the substrate after the immersion, and form the substrate by heat treatment. Other methods include immersing the nib 6 directly in a solution in which an inorganic powder such as silica powder is dispersed in a liquid having affinity with the ink 1 such as the main solvent of the ink 1, or the physical properties and pigments of the ink 1 For example, the particle diameter can be reduced.
In addition, the ink occlusion body 7 is an air-permeable porous body of a polyester resin, a batting which is a fiber bundle of acrylic fiber, nylon fiber, rayon fiber, polypropylene fiber, or a soft resin such as polyethylene resin or urethane resin. In this example, the ink occlusion body 7 is used as a spare tank for replenishing and supplying the ink 1 to the pen tip 6 when the ink 1 of the pen tip 6 is reduced. Depending on the specifications and applications such as ejection of ink 6 and ink 1, when the valve part 4 is opened by pressing the knock part 3, the ink 1 is excessively supplied to the pen tip 6 and the ink 1 drops off. It can also be used as an ink reservoir for suppressing the ink.

As described above, on the inner surface of the front end opening of the front shaft 5, as shown in FIG. 2 which is a cross-sectional view taken along the line II ′ of FIG. The part 5a is formed in the axial direction. The diameters of the inscribed circles of the four convex portions 5a are 10.50 mm so as to be smaller than the diameter of the rear portion 6b of the pen tip 6 so that the rear portion 6b of the pen tip 6 is brought into a pressure-bonded state. The length of the portion to be crimped to the rear portion 6b of 6 is set to 19.6 mm. Further, the space between the four convex portions 5a is caused by the replenishment supply of the ink 1 to the pen tip 6 and the ink occlusion body 7 disposed behind the pen tip 6, or the decrease of the ink 1 stored in the ink tank 2. In order to adjust the pressure to return the decompressed state in the ink tank 2 to the original state, when the valve part 4 is opened by pressing the knock part 3 with a knock, the opening area can be taken in more quickly than the outside air. Is an air circulation groove 5c of 49.7 mm ² .
In particular, since the pen tip 6 of this example has a maximum handwriting width of 12.0 mm as described above, the amount of ink 1 discharged is relatively large among the writing tools, and the saturated ink amount of the pen tip 6 is 2.1 cc. Since the saturated ink amount of the ink occlusion body 7 is 2.5 cc, the amount of ink 1 required for replenishment supply to the pen tip 6 and the ink occlusion body 7 is very large, and the air that needs to be taken in to this amount. Since the opening area is 49.7 mm ² with respect to the length 19.6 mm of the portion to be crimped to the rear part 6 b of the nib 6, the amount of air can be quickly and sufficiently increased. Capture is possible. However, the shape and number of the convex portions 5a, the length, the numerical value, the shape, and the number of the air circulation grooves 5c are not limited to this example, and the type of the ink 1, the shape and dimensions of the nib 6, What is necessary is just to be able to take in necessary air with respect to the discharge amount of the ink 1 according to the specifications such as the saturated ink amount of the nib 6 and the ink occlusion body 7 and the application. For example, in the case of the discharge amount of 1/10 of the ink 1 of this example, even if the opening area of the air circulation groove 5c is about 5 mm ² or more with respect to the length of 19.6 mm and the length is about 10 mm, If it is about 7 mm ² or more, sufficient air can be taken in. Therefore, the length and opening area of the air circulation groove 5c are set according to the pressure bonding performance to the rear part 6b of the pen tip 6, and the convex part 5a. One or two or more may be installed according to the moldability, or the width of the convex portion 5a may be increased.
Further, as described above, the step portion 6 c of the pen tip 6 is locked to the tip step portion 5 b of the convex portion 5 a of the front shaft 5, and the pen tip 6 is fixed to the front shaft 5. The writing portion protruding from the front shaft 5 of the pen tip 6 is prevented from immersing into the shaft tube due to the load received from the writing surface.

In front of the nib 6, a cap 8 made of polypropylene by injection molding covers the nib 6 and is closely fitted to the front shaft 5 so that the inner wall surface 8 a of the cap 8 and the nib 6 do not contact with each other. Yes. As described above, since the tip step portion 5b of the front shaft 5 and the step portion 6c of the pen tip 6 are locked in front of the rear portion 6b of the pen tip 6, it is generated by a radial load received from the writing surface. The deformation of the nib 6 prevents the step 6c of the nib 6 from being a fulcrum and adding to the rear part 6b of the nib 6. For this reason, since the pen tip 6 as a whole is not deformed, the contact between the inner wall surface of the cap 8 and the pen tip 6 is suppressed when the cap 8 is mounted. As long as the inner wall surface 8a and the nib 6 are not in contact with each other, there is no need for the cap 8 to have a special shape or size. For example, the cap 8 is fitted to the knock portion 3 during use. You may make it wearable so that it can be used as a knock assisting body.

Behind the ink occlusion body 7, an ink tank 2 containing the ink 1 in a free state and a lid portion 9 for partitioning the occlusion body are arranged, and a valve seat 9 b is formed in the front cylinder portion 9 a of the lid portion 9. The valve portion 4 is brought into close contact with the valve seat 9b by the rearward biasing of the knock rod 10 and the spring 11 so that the valve portion 4 does not open unless the knock portion 3 is pressed.

The knock bar 10 is inserted into the knock bar guide portion 2b at the bottom of the ink tank 2 having a movable portion 2a formed of a thin portion having a substantially trapezoidal step shape, and presses the knock portion 3. Thus, the movable portion 2a is deformed and the knock rod 10 and the valve portion 4 connected to the knock rod 10 are opened.

FIG. 3 shows another example.
The one shown in FIG. 3 uses the same shaft cylinder, valve mechanism, ink, and the like as in the example shown in FIG. 1, and the pen tip 6 has a diameter A of the front portion 6a and the tip of the tip 6 from the step portion 6c. The length B to the part is 12.0 mm, and the shape of the writing surface of the front part 6a of the nib 6 is hemispherical. For this reason, as in the example of FIG. 1, the deformation of the pen tip 6 with respect to the load applied from the writing surface during writing is suppressed as much as possible. Therefore, there is no trouble of changing the shaft tube in accordance with the tip shape of the nib 6, and it can be extremely suitable for usability.

DESCRIPTION OF SYMBOLS 1 Ink 2 Ink tank 2a Movable part 2b Knock stick guide part 3 Knock part 4 Valve part 5 Front shaft 5a Convex part 5b Tip step part 5c Air circulation groove 6 Pen tip 6a Front part 6b Back part 6c Step part 7 Ink occlusion body 8 Cap 8a Inner wall surface 9 Lid portion 9a Front cylinder portion 9b Valve seat 10 Knock stick 11 Spring

Claims (3)

  The ink is contained in the shaft cylinder, and the nib made of a fiber or porous body serving as an ink discharge portion is fixed to the inner surface of the tip opening portion where the air circulation groove of the shaft cylinder is formed, and the writing portion of the pen tip is fixed. A writing instrument that protrudes from the tip opening of the shaft tube, and is provided with a nib crimping convex portion for crimping and fixing the outer surface of the nib on the inner surface of the tip opening of the shaft tube, and this nib crimping projection on the nib A step of partitioning a rear part to be fixed to the front part and a front part to be a side to form a writing part, and abutting a tip part of a pen tip crimping convex part of the shaft tube to lock the pen point to the shaft tube Writing instrument with a part.   The writing instrument according to claim 1, wherein an inscribed diameter of the nib crimping convex portion of the shaft cylinder is formed to be 95% or less of a diameter of the front portion of the nib. The length from the said step part which divides the said front part and the said back part of the said nib to the forefront of the said nib is below the diameter of the said front part of the said nib. Writing instrument as described.

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