JP5349237B2 - Writing instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a writing utensil to which a first core (e.g., core of oil-based ink) and a second core (e.g., core of gel ink) having larger inner and outer diameters than the first core can be fitted selectively, and which is so designed as to surely prevent the slip-off of the first and second cores even if the cores are of types not being actuated directly by a spiral spring but projecting and retracting while revolving. <P>SOLUTION: In the writing utensil 1, a core holding part 12 which can selectively hold the first core A and the second core B has a bottom 12c with which the rear end of the first core A comes into contact, a core holding pin 30 which is erected from the bottom 12c and pressed in from a rear end opening of the first core A, a protruding portion 31 which is positioned in front of the bottom 12c and protrudes from the inner wall surface of the core holding part 12 so as to be pressed on the outer peripheral surface of the second core B, and a first step 32 which is formed on the inner wall surface of the core holding part 12 at the back of the protruding portion 31 and with which the rear end of the second core B comes into contact. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention provides a first core (for example, the core of oil-based ink) and a second core (for example, the core of gel ink) having a larger inner diameter and outer diameter than the first core. The present invention relates to a writing instrument that can be selectively held with respect to a holding unit.

  Select a first core (for example, the core of oil-based ink) and a second core (for example, the core of gel ink) having a larger inner diameter and outer diameter and a shorter length than the first core. Japanese Patent Application Laid-Open No. 11-254878 is available as a writing instrument that can be attached to the instrument. In the writing instrument described in this publication, the tail plug or the knock body is formed with an engagement hole that allows the rear end side of the first core having a small diameter to be inserted. Therefore, the first inner core can be locked in the tail plug or the knock body by inserting the rear side of the first core into the engagement hole of the tail plug or the knock body. Further, the rear side of the second core having a large diameter is locked to the end face of the tail plug or the knock body. In this manner, the first core (for example, the core of oil-based ink) and the second core (for example, the core of gel ink) having a large inner diameter and outer diameter and a short length with respect to the first core. ) Can be applied. And since these center cores are urged directly by the coil spring on the front side of the shaft tube, the center cores do not need to be firmly held by the tail plugs or knock bodies.

Japanese Patent Laid-Open No. 11-254878

  However, the known writing instrument described above has a first core (for example, the core of oil-based ink) and a second core (for example, a core having a larger inner diameter and outer diameter and a shorter length than the first core). However, it is not planned to be used as a writing instrument that does not bias the core with a coil spring. In particular, in a writing instrument that protrudes from the tip of the writing instrument while the core rotates, it is necessary to hold the core firmly in the core holding part that functions as a rotor.

  In the present invention, the first core (for example, the center of oil-based ink) and the first core are not directly urged by the spiral spring and the core is of a type that appears while rotating. A second core (for example, a gel ink core) having a larger inner diameter and outer diameter than that of the core can be selectively mounted to reliably prevent the first and second cores from coming off. An object is to provide a writing instrument.

The present invention is a writing instrument capable of selectively holding a first core and a second core having a larger inner diameter and outer diameter than the first core with respect to the core holding portion. ,
In the core holding part that has a cylindrical shape with a bottom,
A core holding pin which is erected from the bottom and press-fitted from the rear end opening of the first core;
And a protruding portion that is positioned forward of the bottom portion and protrudes from the inner wall surface of the core holding portion and is crimped to the outer peripheral surface of the second core.

  In this writing instrument, the first core (for example, the core of oil-based ink) is press-fitted with the core holding pin of the center core holding portion from the rear end opening, and the second core (for example, the core of gel ink) is The protruding portion of the core holding portion is pressure-bonded to the outer peripheral surface. With this configuration, two types of different cores can be selectively applied without replacing the core holding portion, and the first and second cores can be reliably prevented from coming off. can do.

In addition, it is preferable that the inner wall surface of the core holding portion is provided with a first step portion that bulges behind the protruding portion and contacts the rear end of the second core.
With such a configuration, the thick and short second core can be easily applied.

In addition, it is preferable that a second step portion that bulges and contacts the rear end of the first core is provided in the middle of the core holding pin.
With such a configuration, the thin and short first core can be easily applied.

Further, the center core holding portion is formed by a spiral spring disposed between the tip of the center core holding portion that slides and rotates along the inner wall surface of the tube portion and a spring receiving portion that protrudes from the inner wall surface of the tube portion. It is preferable to be biased toward the rear.
In this configuration, the central core is not directly biased by the spiral spring, and the central core holding portion functions as a rotor, and the present invention is particularly effective for the writing instrument having such a configuration.

  According to the present invention, the first core (for example, the core of oil-based ink), even if the core is not directly biased by the spiral spring and the core is projected and retracted while rotating, A second core having a larger inner diameter and outer diameter than the first core (for example, a gel ink core) can be selectively mounted, and the first and second cores can be securely removed. Can be prevented.

It is sectional drawing which shows one Embodiment of the writing instrument which concerns on this invention. It is sectional drawing which shows the writing instrument after knocking. It is sectional drawing which shows a center core holding unit. It is a perspective view which shows the state which accommodated the spiral spring in the inside piece. It is the schematic which shows a knock mechanism. (a) is a front view of a center core holding part, (b) is a rear view of the center core holding part, and (c) is a cross-sectional view taken along line II in FIG. 6 (b). It is sectional drawing which follows the II-II line of FIG.6 (b). It is sectional drawing which shows the state which mounted | wore the 1st core with the center core holding | maintenance part. It is sectional drawing which shows the state which mounted | wore the 2nd center core with the center core holding | maintenance part. It is sectional drawing which shows the other example of a center core holding part. It is sectional drawing which shows the further another example of a center core holding | maintenance part.

  Hereinafter, preferred embodiments of a writing instrument according to the present invention will be described in detail with reference to the drawings. In the following description, the pen tip side is referred to as “front side”.

  As shown in FIG. 1, the writing instrument 1 is a knock type, and has a synthetic resin shaft cylinder (cylinder part) 2 that houses a core (refill) 3. The shaft cylinder 2 includes a shaft portion main body 2a in which a clip 4 is integrally formed, and a tip opening 2b screwed to the tip of the shaft portion main body 2a. At the rear end of the shaft tube 2, a knock cap 17 for allowing the core 3 to be taken in and out from the tip of the shaft tube 2 protrudes, and a rubber grip portion 7 is fixed to the grip portion of the shaft tube 2.

  A core holding unit 10 is loaded in the shaft body 2a of the shaft tube 2 forming the outer shell. As shown in FIG. 3, the core holding unit 10 includes a cylindrical middle piece 11 (cylinder part) fixed along the inner wall surface 2 a </ i> A of the shaft body 2 a, and the inner wall surface 11 a of the middle piece 11. A cylindrical central core holding portion 12 that is slidable and holds the rear end of the central core 3, and a spiral spring 13 that urges the central core holding portion 12 toward the rear end side of the shaft body 2a. And a knock portion 6 that is attached to the middle piece 11 and presses the core holding portion 12 against the urging force of the spiral spring 13.

  The knock portion 6 is a knock rod that protrudes from the rear end of the middle piece 11, and the rear end of the knock rod 6 is inserted into the front end side of the cylindrical knock cap 17 that protrudes from the shaft portion main body 2a to be locked. It has been made. A step portion 6 b is formed on the outer peripheral surface of the front end of the knock bar 6, a reduced diameter portion 11 e is formed at the rear end of the middle piece 11, and the step portion 6 b of the knock bar 6 is reduced in diameter portion 11 e of the intermediate piece 11. The knock bar 6 is prevented from coming off.

  The core holding unit 10 has a knock mechanism 20, and as shown in FIG. 5, the knock mechanism 20 includes an angled tooth portion 6 a that is annularly arranged at the tip of the knock bar 6 and forms an isosceles triangle, and a rotor. Formed on the inner wall 11a of the intermediate piece 11 and the protrusion 21 protruding radially from the peripheral surface of the core holding part 12 rotating in the circumferential direction in the intermediate piece 11, the end of the protrusion 21 is The two-step sawtooth portion 11b to be locked and the slide groove 11c formed on the inner wall surface of the intermediate piece 11 and extending in the direction of the axis L between the pair of sawtooth portions 11b. The strip 21 and the slide groove 11c are formed every 120 degrees in the circumferential direction. And the inclined surface 21a is formed in the edge part of the protruding part 21, This inclined surface 21a engages with the chevron tooth part 6a, when projecting the center core 3 from an immersion state, and the center core 3 protrudes. Sometimes it engages the sawtooth portion 11b.

  The operation of the knock mechanism 20 will be briefly described. As shown in FIG. 5A, when the knock cap 17 is pushed with a finger, the knock bar 6 moves forward, and the ridge portion 21 near the top of the chevron tooth portion 6a. When the inclined surface 21a is pushed, the core holding part 12 moves forward. At this time, the protrusion 21 slides along the slide groove 11c. Then, as shown in FIG. 5B, when the knock cap 17 is continuously pressed, the ridge portion 21 is detached from the slide groove 11 c, and the inclined surface 21 a of the ridge portion 21 is angled by the urging force of the spiral spring 13. It moves slightly along the slope of 6a, and accordingly, the core holding part 12 is slightly rotated.

  Thereafter, as shown in FIG. 5 (c), when the finger is released from the knock cap 17, the protrusion 21 is retracted by the urging force of the spiral spring 13. At this time, the inclined surface 21a of the protrusion 21 is engaged with the top of the upstream sawtooth portion 11b, and the inclined surface 21a of the protrusion 21 moves along the inclined surface of the upstream sawtooth portion 11b. Accordingly, the core holding part 12 rotates. Then, the inclined surface 21a of the ridge portion 21 is engaged with the valley portion 11f between the sawtooth portions 11b, whereby the rotation and retraction of the core holding portion 12 are stopped. As a result, as shown in FIG. 2, the tip of the core 3 protrudes from the tip 2b and enters a writing state.

  As shown in FIG. 5D, when the knock cap 17 is pushed from the written state, the inclined surface 21a of the protruding portion 21 is pushed in the vicinity of the top of the chevron tooth portion 6a, so that the core holding portion 12 moves forward. . At this time, the protrusion 21 slides along the upright surface 11d between the sawtooth portions 11b. When the knock cap 17 is kept pressed, the protrusion 21 is disengaged from the sawtooth portion 11b, and the inclined surface 21a of the protrusion 21 is slightly moved along the slope of the angle tooth portion 6a by the biasing force of the spiral spring 13. Accordingly, the core holding part 12 is slightly rotated.

  Thereafter, when the finger is released from the knock cap 17, the protruding portion 21 is retracted by the biasing force of the spiral spring 13. At this time, the inclined surface 21a of the ridge portion 21 is engaged with the top of the downstream sawtooth portion 11b, and the inclined surface 21a of the ridge portion 21 moves along the inclined surface of the downstream sawtooth portion 11b. Accordingly, the core holding part 12 rotates. And the core holding | maintenance part 12 reverse | retreats because the protrusion part 21 falls in the next slide groove 11c. Thereby, as shown in FIG. 1, the front-end | tip of the center core 3 enters in the front opening 2b.

  Such a knock mechanism 20 is known from Japanese Patent No. 4153314.

  As shown in FIGS. 3 and 4, the cylindrical intermediate piece 11 is formed with a claw piece (spring receiving portion) 23 positioned in front of the core holding portion 12. The claw pieces 23 are provided every 180 degrees in the circumferential direction of the middle piece 11, and the claw pieces 23 extending in the direction of the axis L are produced by forming a U-shaped slit 24 in the middle piece 11 at the time of injection molding. It is. The tip 23 a of each claw piece 23 faces the tip 12 a of the core holding part 12, and the end of the spiral spring 13 is held by the tip 23 a of the claw piece 23 and the tip 12 a of the core holding part 12. Such a claw piece 23 forms a part of the middle piece 11 and is bent in a “<” shape toward the inside from a state extending along the axis L.

  In assembling such a core holding unit 10, first, the knock bar 6 is inserted from the front end opening of the center piece 11, and then the core holding part 12 is inserted. After that, the spiral spring 13 is inserted, and a flat spring push rod 26 is inserted from the front end opening of the middle piece 11 so that the spiral spring 13 is compressed. Thereafter, the tip 23 a of the claw piece 23 is inserted into the middle piece 11 so that the claw piece 23 is bent in a “<” shape. In this way, the spiral spring 13 is locked at the tip 23 a of the claw piece 23 only by bending the claw piece 23 in the shape of “<”, and the spiral spring 13 is thereby locked from the opening of the tip of the middle piece 11. Will not fall out. When a claw piece 23 that can be bent inward is used as a part of the middle piece 11, no additional parts for supporting the spiral spring 13 are required, so that the structure can be simplified and the cost and weight can be reduced. it can.

  Further, on the outer surface of the claw piece 23, a hemispherical protrusion 23b that abuts against the inner wall surface 2aA of the shaft tube 2 is formed. Accordingly, when the core holding unit 10 is inserted into the shaft cylinder 2, the protrusion 23b of the claw piece 23 continues to be restricted by the inner wall surface 2aA of the claw piece 2, so that the claw piece is assembled during or after the writing instrument 1 is assembled. Thus, the helical spring 13 can be reliably kept locked at the tip 23a of the 23, and the falling of the helical spring 13 can be reliably prevented.

  Further, two ring-shaped locking projections 28 are formed on the outer wall surface of the middle piece 11, and the locking projections 28 are fitted and locked on the inner wall surface 2aA of the shaft cylinder 2. A ring-shaped recess 27 is formed. Accordingly, when the core holding unit 10 is inserted along the shaft cylinder 2, the locking projection 28 of the center piece 11 enters the recess 27 of the shaft cylinder 2, so that the core holding unit 10 can be touched in the shaft cylinder 2 with one touch. Can be fixed easily. Such a configuration, combined with the use of the protrusion 23b of the claw piece 23, enables one-touch mounting in the shaft cylinder 2 in the core holding unit 10 and improves assembly workability.

  Next, the core holding part 12 will be described in detail.

  As shown in FIG. 6 and FIG. 7, the core holding part 12 functioning as a rotor is filled with, for example, a first core A (see FIG. 8) filled with oil-based ink and gel ink, for example. It is possible to selectively hold the second core B (see FIG. 9) having a large inner diameter and outer diameter and a short length with respect to the one core.

  The core holding part 12 has a bottomed cylindrical shape and has a core insertion hole 12b along the axis L. The first core A enters the bottom 12c of the core insertion hole 12b, and the second core B enters until the center insertion hole 12b comes into contact with a first step portion 32 described later.

  A core holding pin 30 is erected from the bottom 12c of the core insertion hole 12b. The core holding pin 30 is formed in a square cross section and protrudes to about half of the core insertion hole 12b. Further, the front end of the core holding pin 30 is formed in a regular quadrangular pyramid in order to facilitate the insertion into the rear end opening a of the first core A.

  Furthermore, the inner core wall 12d of the center core holding portion 12 is positioned in front of the bottom portion 12c, protrudes in the radial direction from the inner wall surface 12d of the center core holding portion 12, and is crimped to the outer peripheral surface of the second core core B. A first step portion that is formed on the inner wall surface 12d of the core holding portion 12 at the rear of the protruding portion 31 and the protruding portion 31, and the rear end of the second inner core B abuts by bulging in the radial direction. 32.

  The protrusion 31 is formed on the inner peripheral surface 12d with a phase angle of 180 degrees, and has a flat press-fit surface 31a extending along the axis L. The outer surface of the second core B can be reliably crimped to the protruding portion 31 by the flat press-fitting surface 31a. An inclined surface 31 b is formed at the front end of the protruding portion 31 to facilitate the press-fitting of the second core B.

  The first step portion 32 is formed by reducing the diameter of the rear end side of the inner wall surface 12 d extending in the direction of the axis L, and the first step portion 32 is located behind the front end of the core holding pin 30. positioned. And the space | interval of the 1st level | step-difference part 32 and the bottom part 12c is set corresponding to the length of the 1st center core A and the 2nd center core B. As shown in FIG.

  As shown in FIG. 8, in the first core (for example, the core of oil-based ink) A, the core holding pin 30 of the core holding portion 12 is press-fitted from the rear end opening a. At this time, the corner portion 30a of the core holding pin 30 is crimped so as to bite into the inner wall surface of the first core A, and the corner portion 30a is substantially lined with the inner wall surface of the first core A. Since it is in a contact state, the core holding pin 30 can be smoothly press-fitted into the first core A. Then, the rear end of the first core A contacts the bottom, and the first core A is positioned.

  As shown in FIG. 9, the outer peripheral surface of the second core (for example, the core of gel ink) B is pressure-bonded to the flat press-fitting surface 31 a of the protruding portion 31 of the core holding portion 12. Then, the rear end of the second core B comes into contact with the first step portion 32, and the second core B is positioned.

  By configuring in this way, the thin and long first core A and the thick and short second core B can be selectively applied without exchanging the core holding part 12. It is possible to reliably prevent the first and second cores A and B from coming off.

  It goes without saying that the present invention is not limited to the embodiment described above.

  As shown in FIG. 10, the first step portion 32 is not provided in the other core holding portion 40, and the rear end of the second core B is in contact with the bottom portion 12 c. Therefore, the thin first core A and the thick second core B having the same length can be selectively applied. Other configurations are the same as those of the core holding unit 12.

  As shown in FIG. 11, the other core holding part 50 is not provided with the first stepped portion 32, and the rear end of the second core B is in contact with the bottom 12c. Further, in the middle of the core holding pin 51, there is provided a second step portion 52 that bulges in the radial direction and contacts the rear end of the first core A. Therefore, the thin and short first core A and the thick and long second core B can be selectively applied. Other configurations are the same as those of the core holding unit 12.

  As the tube portion, there are the shaft tube 2 and the middle piece 11, and a claw piece (spring receiving portion) 23 may be provided in any of them.

  The present invention can also be applied to a writing instrument in which the core is directly urged by a spiral spring, or a writing instrument in which the core is projected and retracted without rotating.

  The present invention is not limited to a knock-type writing instrument, and can also be applied to a writing instrument in which the core holding part rotates and the core moves up and down together with the rotation of the shaft tube. It can also be applied to a type of writing instrument that is integrally formed with the core and does not appear and disappear.

  As the other core holding portion (not shown), both the first step portion 32 and the second step portion 52 described above may be formed.

  DESCRIPTION OF SYMBOLS 1 ... Writing instrument, 2 ... Shaft cylinder (cylinder part), 11 ... Middle piece (cylinder part), 12, 40, 50 ... Core holding part, 12c ... Bottom part, 12d ... Inner wall surface (inner peripheral surface), 23 ... Nail | claw Piece (spring receiving part), 13 ... spiral spring, 30, 51 ... core holding pin, 31 ... projecting part, 32 ... first step part, 52 ... second step part, A ... first core, B ... second core, a ... rear end opening, L ... axis.

Claims (4)

A writing instrument capable of selectively holding a first core and a second core having a larger inner diameter and outer diameter than the first core with respect to the core holding part,
In the core holding portion having a bottomed cylindrical shape,
A core holding pin erected from the bottom and press-fitted from the rear end opening of the first core;
A writing instrument, characterized in that a writing part is provided in front of the bottom part, protruding from an inner wall surface of the core holding part and crimped to an outer peripheral surface of the second core.   2. The first step portion is provided on the inner wall surface of the core holding portion so as to bulge behind the projecting portion and contact the rear end of the second core. Writing instrument as described.   3. The writing instrument according to claim 1, wherein a second stepped portion is provided in the middle of the core holding pin so as to bulge and abut the rear end of the first core. 4.   The center core holding portion is a spiral spring disposed between the tip of the center core holding portion that slides and rotates along the inner wall surface of the cylindrical portion and a spring receiving portion that protrudes from the inner wall surface of the cylindrical portion. The writing instrument according to any one of claims 1 to 3, wherein the writing instrument is urged rearward by the head.

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