JP7139506B2 - writing instrument - Google Patents

Description

The present invention relates to writing instruments. More particularly, the present invention relates to a writing instrument of a type in which a valve device is opened by pushing the pen body backward to supply ink in an ink reservoir to the pen body.

Conventionally, for example, Patent Document 1 discloses a writing instrument body having an ink chamber, a front barrel having a holding portion provided at the tip of the writing instrument body, an ink holder fitted in the front barrel, and the ink chamber. a valve mechanism mounted in an opening; and a pen core projecting outward through the valve mechanism and inserted and held in the holding portion and the ink holding body in the front barrel, wherein the ink holding An ink retaining device for a writing instrument that retains ink on its body is described.

Utility Model Registration No. 2594990

In the writing instrument disclosed in Patent Document 1, when an ink retainer made of sponge or the like (corresponding to the ink absorber of the present application) is attached in the front barrel, the ink is retained due to unstable contact between the ink retainer and the inner surface of the front barrel. There is a possibility that the ink holder may be assembled in a defective manner such that the ink holder is installed at an angle to the inner surface of the front barrel.

SUMMARY OF THE INVENTION The present invention is intended to solve the conventional problems described above, and provides a writing instrument in which the ink absorber can be smoothly inserted into the front barrel, and as a result, the ink absorber can be properly mounted in the front barrel. I am trying to.

In the present invention, "front" refers to the pen body side, and "rear" refers to the opposite side.

A writing instrument according to a first aspect of the present invention comprises a pen body, a front shaft holding the pen body at a front end so as to be movable in the front-rear direction, and a front end screwed to the front shaft and having an ink reservoir therein. a valve device arranged at a front end opening of the rear barrel and opened by pressing the pen body backward; and an annular ink cartridge made of a porous material arranged in the front barrel. an absorber, wherein an absorber holding portion is formed on the inner surface of the front barrel to press and hold the outer surface of the ink absorber, and the absorber holding portion has a satin surface composed of fine unevenness. required to have

In the writing instrument according to the first aspect of the present invention, when the ink absorber is inserted into the front barrel, the contact resistance between the inner surface of the absorber holding portion and the ink absorber can be reduced. can be smoothly inserted into the As a result, the ink absorber can be properly mounted inside the front shaft, and the occurrence of defective assembly of the ink holder can be prevented.

A writing instrument according to a second invention of the present application is the writing instrument according to the first invention, wherein the satin-finished surface is circumferentially formed on the inner surface of the absorber holding portion.

In the writing instrument according to the second aspect of the present invention, when the ink absorber is inserted into the front barrel, the contact resistance between the inner surface of the absorber holding portion and the ink absorber can be reduced, and the inner surface of the absorber holding portion and the ink absorber can be A stable contact with the ink absorber can be obtained, and the ink absorber can be more smoothly inserted into the front shaft. As a result, the ink absorber can be properly mounted inside the front shaft, and the occurrence of defective assembly of the ink holder can be prevented.

A writing instrument according to a third invention of the present application is the writing instrument according to the second invention, wherein the satin surface is formed on the entire peripheral surface of the absorber holding portion.

In the writing instrument according to the third aspect of the present invention, when the ink absorber is inserted into the front barrel, the contact resistance between the inner surface of the absorber holding portion and the ink absorber can be reduced, and the inner surface of the absorber holding portion and the ink absorber can be A stable contact with the ink absorber can be reliably obtained, and the ink absorber can be more smoothly inserted into the front shaft. As a result, the ink absorber can be properly and reliably mounted inside the front shaft, and the occurrence of defective assembly of the ink holder can be prevented.

A writing instrument according to a fourth invention of the present application is the writing instrument according to any one of the first to third inventions, wherein the arithmetic mean roughness (Ra) of the satin surface is in the range of 5 μm to 50 μm. .

According to the fourth aspect of the present invention, the writing instrument having the above-described configuration can appropriately reduce the contact resistance between the inner surface of the absorber holding portion and the ink absorber when the ink absorber is inserted into the front barrel, and also has an appropriate satin surface. Since it can be formed, more stable contact can be obtained between the inner surface of the absorber holding portion and the ink absorber, and the ink absorber can be more smoothly inserted into the front shaft. As a result, the ink absorber can be properly and reliably mounted inside the front shaft, and the occurrence of defective assembly of the ink holder can be prevented.

A writing instrument according to a fifth invention of the present application is the writing instrument according to any one of the first to fourth inventions, wherein the absorber holding portion has a draft angle of 0.2 degrees to 3.0 degrees. and

With the above configuration, the writing instrument according to the fifth aspect of the present invention can improve releasability and transferability to the mold surface (matte surface). As a result, the ink absorber can be properly and reliably mounted in the front shaft, the occurrence of defective assembly of the ink retainer can be prevented, and parts can be molded with high productivity.

A writing instrument according to a sixth invention of the present application is the writing instrument according to any one of the first to fifth inventions, wherein the ink absorber is attached to the absorber holding portion in the front barrel, It is required to be in a radially compressed state by the absorbent body holding portion.

In the writing instrument according to the sixth aspect of the present invention, due to the configuration described above, when the ink absorber is attached to the absorber holding portion in the front barrel, excessive resistance is not generated and the ink absorber is securely attached to the absorber holding portion. It becomes possible to fit into

ADVANTAGE OF THE INVENTION The writing instrument of this invention can insert an ink absorber smoothly in a front barrel, and as a result, the writing instrument which can attach an ink absorber in a front barrel appropriately can be provided.

1 is a longitudinal sectional view of an embodiment of the invention; FIG. FIG. 2 is an enlarged vertical cross-sectional view of a main portion of FIG. 1; 2 is a longitudinal sectional view showing a state before an ink absorber is attached inside the front shaft of FIG. 1; FIG. FIG. 2 is a longitudinal sectional view showing a state after an ink absorber is attached inside the front shaft of FIG. 1;

An embodiment of the writing instrument of the present invention will be described with reference to the drawings. (See Figures 1 to 4)

The writing instrument 1 of the present invention comprises a pen body 2, a front barrel 3 at the front end of which the pen body 2 is held so as to be movable in the front-rear direction, and an ink reservoir in which the front barrel 3 is screwed into the front end. a valve device 5 arranged at a front end opening of the rear barrel 4 and opened by pushing the pen body 2 backward; and a porous material arranged in the front barrel 3. and an annular ink absorber 10.

- Front shaft The front shaft 3 is a tapered cylindrical body with both ends opened, and is obtained by injection molding of synthetic resin. A pen body holding portion 31 is formed on the inner surface of the front end portion of the front barrel 3 . The pen body holding portion 31 has a plurality of vertical ribs extending in the front-rear direction, and the vertical ribs slidably hold the pen body 2 . A threaded portion 33 is formed on the inner surface of the rear end portion of the front shaft 3 . A threaded portion 33 on the inner surface of the rear end portion of the front shaft 3 is screwed to a threaded portion 41 on the outer surface of the front end portion of the rear shaft 4 .

On the inner peripheral surface of the front barrel 3 behind the pen body holding portion 31 and in front of the threaded portion 33, there is formed an absorber holding portion 32 in which the ink absorber 10 is pressed against and held. The absorber holding portion 32 has a satin surface 32a having fine unevenness on the entire peripheral surface. In a state in which the ink absorber 10 is attached to the absorber holding portion 32 in the front shaft 3, the outer peripheral surface of the ink absorber 10 is radially compressed by the absorber holding portion 32 in the front shaft 3. .

The arithmetic mean roughness (Ra) of the satin surface 32a is preferably in the range of 5 μm to 50 μm. When the thickness is smaller than 5 μm, the surface of the absorber holding portion 32 becomes close to a mirror surface, the contact resistance between the inner surface of the absorber holding portion 32 and the ink absorber 10 increases, and the ink absorber 10 can be smoothly inserted into the front shaft. It may become impossible to do so. On the other hand, if it is larger than 50 μm, it becomes difficult to release from the mold and sufficient transferability to the mold surface (matte surface) cannot be obtained. More preferably, the arithmetic mean roughness (Ra) of the satin surface 32a is in the range of 10 μm to 40 μm. In addition, the range of 10 μm to 25 μm is more preferable in terms of obtaining good releasability and mold surface transferability.

The satin surface 32a can be obtained by subjecting the surface of the mold to etching, sandblasting, polishing other than mirror finishing, or the like. Also, the satin surface 32a can be obtained by leaving the surface of the mold component after electrical discharge machining without polishing or the like.

The arithmetic mean roughness (Ra) of the satin surface 32a refers to the arithmetic mean roughness (Ra) defined in JIS B0601:1982. In addition, for the measurement of the surface roughness at that time, (model name SJ-301 manufactured by Mitutoyo Co., Ltd.) is used.

The absorber holding portion 32 is formed with a draft in order to improve releasability and mold surface transferability. The draft angle is preferably in the range of 0.2 degrees to 3.0 degrees. If the draft angle is less than 0.2 degrees, release from the mold becomes difficult, and there is a possibility that the transferability of the mold surface (pear surface) to the absorber holding portion 32 will deteriorate. On the other hand, if the draft angle is greater than 3.0 degrees, the ink absorber 10 inserted into the absorber holding portion 32 may easily come off. The draft angle is more preferably in the range of 0.5 degrees to 1.5 degrees.

An annular stepped portion 34 is formed on the front inner surface of the threaded portion 33 of the front shaft 3 . A locking stepped portion 35 is formed in front of the annular stepped portion 34 on the inner surface of the front shaft 3 . The front surface of the ink absorber 10 is locked to the locking stepped portion 35 . An absorber holding portion 32 made of a satin surface 32a is formed in the entire region of the inner surface of the front shaft 3 in front of the annular stepped portion 34 and behind the locking stepped portion 35 . The inner surface of the front barrel 3 excluding the absorber holding portion 32 is formed of a smooth surface (non-contact surface).

- Rear shaft The rear shaft 4 is formed of a bottomed cylindrical body with an open front end and a closed rear end, and is obtained by blow molding of synthetic resin. A front end portion of the rear shaft 4 has a reduced diameter, and a threaded portion 41 is formed on the outer surface thereof. An ink reservoir is formed in the rear shaft 4, and ink and a stirring member 11 (spherical body) are accommodated in the ink reservoir.

・Pen Body The pen body 2 is a resin-processed rod-shaped fiber bundle. Both ends of the pen body 2 are tapered. Convex curved surfaces are formed on the apexes of the tapered ends of the pen body 2 .

Ink absorber The ink absorber 10 retains ink from the ink reservoir in order to prevent excess ink from flowing out of the pen body. The ink absorber 10 is made of an elastic open-pore synthetic resin (so-called sponge). The ink absorber 10 has a center hole through which the pen body 2 penetrates, and is formed in an annular shape. For example, the ink absorber 10 can be obtained from polyester-based urethane foam, polyether-based urethane foam, polyolefin foam, or the like.

The ink absorber 10 is made of a bundle of fibers made of polyester, acryl, etc., and is a conventional porous member having interconnecting pores such as resin-processed fibers, fusion-bonded heat-fusible fibers, and felt bodies. It consists of a bundle of fibers. Incidentally, the ink absorber 10 is made of a porous member fiber bundle having open pores and having a porosity preferably selected from a range of approximately 80 to 90%.

Further, the ink absorber 10 is compressed in the radial direction by the absorber holding portion 32 inside the front shaft 3 while being attached to the absorber holding portion 32 inside the front shaft 3 . In addition to the fact that the ink absorber 10 is compressed in the radial direction when it is inserted into the absorber holding portion 32, the absorber holding portion 32 has a satin surface 32a that is made up of fine unevenness. The effect of making it difficult for the ink absorber 10 inserted in the holding portion 32 to come off can be further obtained. Specifically, the outer diameter of the ink absorber 10 before being attached to the absorber holding portion 32 in the front shaft 3 is larger than the inner diameter of the absorber holding portion 32, and the diameter difference is 0 mm to 0.6 mm, more preferably. is 0.1 mm to 0.3 mm.

・Valve device The valve device 5 includes a valve body 6 that abuts on the rear end of the pen body 2 , a valve seat member 7 that has a valve hole 74 that can be freely opened and closed by a close-separating operation with the valve body 6 , and the valve body 6 . and a valve housing cylinder 9 that houses the valve body 6, the valve seat member 7, and the resilient body 8,

Valve body The valve body 6 includes a rod-shaped front part 61, a valve part 62 formed integrally behind the rod-shaped front part 61 and projecting radially outward in an annular shape, and a valve body 6 integrally formed behind the valve part 62. and a bar-shaped rear portion 63 formed in the . The valve body 6 is obtained by injection molding of synthetic resin.

Valve seat member The valve seat member 7 is a cylindrical body with both ends opened, and is obtained by injection molding of synthetic resin. The valve seat member 7 is integrally formed with an annular collar portion 71 protruding radially outward at the front end thereof. A tubular portion 72 is integrally formed behind the flange portion 71 . A seat portion 73 protruding radially inward is integrally formed on the inner surface of the rear end of the cylindrical portion 72 . A valve hole 74 is provided through the center of the seat portion 73 in the front-rear direction. The valve portion 62 of the valve body 6 can be closely spaced from the seat portion 73 .

- Elastic body The elastic body 8 consists of a compression coil spring. A rod-shaped rear portion 63 of the valve body 6 is inserted through the elastic body 8 . The front end of the elastic body 8 is engaged with the rear surface of the valve portion 62 of the valve body 6, and the valve body 6 is urged forward. The rear end of the elastic body 8 is locked to the locking wall portion 93 of the valve housing cylinder 9 .

• Valve-accommodating cylinder The valve-accommodating cylinder 9 is a cylindrical body with both ends opened, and is obtained by injection molding of synthetic resin. The valve housing cylinder 9 is integrally formed with an annular collar portion 91 protruding radially outward at the front end. A cylindrical portion 92 is integrally formed behind the collar portion 91 . A locking wall portion 93 projecting radially inward is integrally formed on the inner surface of the rear end of the cylindrical portion 92 . A guide hole 94 is provided through the center of the locking wall portion 93 in the front-rear direction, and the rod-shaped rear portion 63 of the valve body 6 is inserted through the guide hole 94 . A plurality of ink circulation holes 95 are formed through the rear side wall of the cylindrical portion 92 in the radial direction. The outer surface of the tubular portion 72 of the valve seat member 7 is press-fitted and fixed to the inner surface of the front end opening of the tubular portion 92 of the valve housing cylinder 9 . The front surface of the flange portion 91 of the valve housing cylinder 9 is in close contact with the rear surface of the flange portion 71 of the valve seat member 7 . The rear surface of the collar portion 91 of the valve housing cylinder 9 is brought into close contact with the front end of the rear shaft 4 . The outer surface of the front end portion of the cylindrical portion 92 of the valve housing cylinder 9 is press-fitted and fixed to the inner surface of the front end opening portion of the rear axle 4 . The annular stepped portion 34 of the front shaft 3 is brought into close contact with the front surface of the flange portion 71 of the valve seat member 7 . By screwing the front shaft 3 and the rear shaft 4 together, the flange portion 71 of the valve seat member 7 and the flange portion 91 of the valve housing cylinder 9 are formed between the annular stepped portion 34 of the front shaft 3 and the front end of the rear shaft 4. It is sandwiched in the front-rear direction. A valve body 6, a valve seat member 7 and an elastic body 8 are housed in a valve housing cylinder 9 to obtain a unitized valve device 5. - 特許庁

The writing instrument 1 of this embodiment comprises a pen body 2, a front barrel 3 to which the pen body 2 is held at the front end so as to be movable in the front-rear direction, and a front barrel 3 screwed to the front end and to the inside. a rear barrel 4 having an ink reservoir; a valve device 5 arranged at a front end opening of the rear barrel 4 and opened by pushing the pen body 2 backward; and an annular ink absorber 10 made of a thin material, wherein an absorber holding portion 32 for holding the outer surface of the ink absorber 10 in pressure contact is formed on the inner surface of the front barrel 3, and the absorber The holding portion 32 has a satin surface 32a having fine unevenness.

Thus, in the writing instrument 1 of the present embodiment, when the ink absorber 10 is inserted into the front barrel 3, the contact resistance between the inner surface of the absorber holding portion 32 and the ink absorber 10 can be reduced, and Stable contact between the inner surface of 32 and the ink absorber 10 can be reliably obtained, and the ink absorber 10 can be smoothly inserted into the front portion of the barrel. As a result, the ink absorber 10 can be properly and reliably mounted in the front shaft 3, and the occurrence of defective assembly of the ink holder can be reliably prevented.

1 writing instrument 2 pen body 3 front shaft 31 pen body holding portion 32 absorber holding portion 32a satin surface 33 threaded portion 34 annular stepped portion 35 locking stepped portion 4 rear shaft 41 threaded portion 5 valve device 6 valve body 61 rod-shaped Front part 62 Valve part 63 Rod-shaped rear part 7 Valve seat member 71 Flange part 72 Tubular part 73 Seat part 74 Valve hole 8 Elastic body 9 Valve housing cylinder 91 Flange part 92 Tubular part 93 Locking wall part 94 Guide hole 95 Ink circulation hole 10 Ink absorber 11 Stirring member

Claims (4)

a pen body, a front shaft having said pen body held at its front end, a rear shaft engaged behind said front shaft and having an ink reservoir therein, and a perforation disposed on the inner surface of said front shaft A writing instrument comprising: an annular ink absorber made of a material comprising:
An absorber holding portion is formed on the inner surface of the front shaft to press and hold the outer surface of the ink absorber,
A writing utensil, wherein the absorber holding portion has a satin-finished surface comprising fine irregularities. The writing instrument according to claim 1 , wherein a locking stepped portion is formed on the inner surface of the front barrel to lock the front surface of the ink absorber . The writing instrument according to claim 1 or 2, wherein the front barrel and the rear barrel are engaged by screwing . a pen body, a front shaft having the pen body held at its front end, a rear shaft engaged behind the front shaft and having an ink reservoir therein, and a porous material disposed on the inner surface of the front shaft A method for manufacturing a writing instrument comprising an annular ink absorber consisting of
A writing utensil characterized in that an absorber holding portion having a satin-finished surface comprising fine irregularities is formed on the inner surface of the front barrel, and the outer surface of the ink absorber is inserted while being pressed against the absorber holding portion. manufacturing method.

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