JP2012166504A - Rolling prevention writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling prevention writing utensil that has no clip, the utensil being designed to be less likely to be dropped from a desk or the like by making the center of its gravity low, and being able to ensure the flexibility in design.SOLUTION: In a writing utensil, such as a ball-point pen, mechanical pencil, marker, which is formed by mounting a plurality of writing utensil members in a cylindrical shaft tube and which has no clip, the center of the gravity of the writing utensil is located substantially in the middle of the overall length of the writing utensil when not being used for writing and in a position displaced from the axis of the shaft tube. A weight is fixedly disposed on an internal surface of the shaft tube in the direction of the length of the shaft.

Description

  The present invention relates to a rolling prevention writing instrument that is difficult to drop from a desk or the like.

  Writing instruments such as pencils, mechanical pencils, and ballpoint pens often have a circular shape or the like in which the axial cross section is easily squeezed, so that they can be easily rolled when rotational stress is applied. Therefore, when force is applied to the writing instrument, the writing instrument may roll on the desk, fall off the desk, and pick up from the floor. Moreover, the tip part or the rear end part of the writing instrument may be rotated, and the center of gravity may be moved to fall from the desk. For this reason, in order to prevent rolling, a pencil (Patent Document 1) that has a shaft cross-sectional shape processed into an atypical shape and has a center of gravity lowered so as to be stationary at a fixed position (Patent Document 1) or a shaft There has been proposed a pencil (Patent Document 2) and the like that are made difficult to slip by forming protrusions on the surface.

  However, as in Patent Document 1, the processing of the shaft cross-sectional shape into an atypical shape is a production facility considering that plastic and metal are frequently used as the material of the shaft cylinder in mechanical pencils, ballpoint pens, etc. It is difficult to say that the method is excellent in terms of production efficiency.

  In addition, as in Patent Document 2, the formation of protrusions can be expected to have a certain effect in preventing rolling. However, a mechanical pencil, a ballpoint pen, or the like is equipped with a clip, and the clip itself has an anti-rolling action. is there. However, in order to expect the effect of preventing rolling (preventing falling) in a writing instrument equipped with a clip, it is necessary to form the clip large, and thus the design is also limited.

JP 2007-098588 A Japanese Utility Model Publication No. 2-088794

  As mentioned above, the conventional anti-rolling writing instruments have been given the anti-rolling action by devising the cross-section of the shaft and the shape of the surface, and are particularly suitable for writing instruments that do not have clips and are easy to roll. However, for writing instruments such as mechanical pencils and ballpoint pens that have multiple writing instrument members installed in the shaft cylinder, there are problems such as eliminating the freedom of design by installing clips. is doing.

  Accordingly, the present invention aims to provide a rolling-preventing writing instrument that does not have a clip and has a low center of gravity and that is difficult to drop from a desk or the like and that can ensure a degree of design freedom in order to solve the conventional problems. And

  As a result of intensive studies to solve the above problems, the present inventor has mounted a weight on a writing instrument and lowered the center of gravity of the writing instrument in the axial direction, that is, the center of gravity is reduced from the axis of the axial cylinder to the surface of the axial cylinder. Focusing on the fact that moving to the side (outside) increases the stress required to roll the writing instrument, so that even if there is no clip, a certain degree of rolling prevention effect can be expected, and the degree of freedom in design increases. In addition, by lowering the center of gravity of the writing cylinder in the axial short direction and adjusting the position of the center of gravity of the axial cylinder in the longitudinal direction of the writing cylinder, rolling stress causes lateral rolling in the axial direction of the axial cylinder, It was found that a state of swaying while the swaying attenuated appeared.

  In order to achieve the above object, the present invention provides a writing instrument having the following configuration.

(1) A writing instrument that does not have a clip in which a plurality of writing instrument members are mounted in a cylindrical shaft cylinder, the center of gravity of the writing instrument being substantially the center of the entire length of the writing instrument that is not in the writing state, and the axis of the shaft cylinder A writing instrument, wherein the writing instrument is located at a position deviated from the center, and a weight is fixedly disposed on an inner surface of the shaft tube in a longitudinal direction of the shaft.
(2) The writing instrument according to (1), wherein the writing instrument moves in such a manner that the shaking in the lateral direction of the axial tube is attenuated.

  According to the present invention, since the center of gravity in the lateral direction of the shaft is designed to be low due to the action of the weight, it becomes a writing instrument that is difficult to move on the desk, etc., and difficult to drop from the desk, etc. Secured. In addition, since the center of gravity is located at the approximate center of the entire length of the writing instrument in use, the roll oscillates as it sways swaying by rolling in the axial direction of the barrel when rotational stress is applied. Can provide cute and fun writing instruments.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the ball-point pen of Embodiment 1 of this invention, (a) is the partial cross section schematic in an axial longitudinal direction, (b) is AA 'cross section. It is a figure which shows the ball-point pen of Embodiment 2 of this invention, (a) is the partial cross section schematic in an axial longitudinal direction, (b) is BB 'sectional drawing. It is a figure which shows the ball-point pen of Embodiment 3 of this invention, (a) is the partial cross section schematic in an axial longitudinal direction, (b) is CC 'sectional drawing. It is a figure which shows the partial cross section schematic diagram in the axial longitudinal direction of the ball-point pen of Embodiment 4 of this invention which provided the rolling stopper in the ball-point pen of Embodiment 1. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to what shows the same member and the same location.

  1A and 1B are diagrams showing a ballpoint pen according to a first embodiment of the present invention, in which FIG. 1A is a schematic partial cross-sectional view in the axial longitudinal direction, and FIG. 1B is a cross-sectional view along AA ′. In FIG. 1, the ball-point pen which is not in a writing state is shown.

  In FIG. 1, 1 is a writing instrument (ballpoint pen), 2 is a shaft cylinder of the writing instrument, 3 is a refill made of plastic filled with ballpoint pen ink, and 4 is a protrusion of the refill 3. 5 is a rotary cam that is connected to the rear end of the refill 3 and has a protrusion on the peripheral side that engages with the cam groove, and is provided so as to be movable in the shaft cylinder 2 along the cam groove. A fixed cam 7 connected to the rear end portion of the rotating cam 5 and movable along the cam groove in the shaft cylinder 2 is connected to the rear end portion of the fixed cam 6. The knock member for pressing is shown. Reference numeral 8 denotes a front end portion of the writing instrument 1, and 8 a denotes a front end opening for projecting the pen tip from the front end portion 8. Reference numeral 9 denotes a weight provided on the inner surface of the shaft cylinder 2. X indicates the axis of the shaft 2 of the ballpoint pen, and G indicates the position of the center of gravity of the ballpoint pen.

  In FIG. 1, when the knock member 7 is knocked, that is, pushed down by the user, a fixed cam 6 in which the knock member 7 and the rear end portion are connected, and a rotating cam 5 in which the fixed cam 6 and the rear end portion are connected. However, it moves in the axial tube 2 along the cam groove in the direction of the tip 8. Further, the refill 3 that is in contact with the rotary cam 5 at the rear end portion by the knock moves in the shaft cylinder 2, and the writing portion (ball) protrudes from the front end opening portion 8a so that writing is possible.

  In FIG. 1, the weight 9 has only to be arranged on the inner surface of the shaft cylinder 2 in the writing instrument 1 in the axial longitudinal direction. If the center of gravity of the writing instrument is substantially at the center of the entire writing instrument not in the writing state, the length is It is not limited. The weight 9 may be provided only on a part of the inner surface of the shaft cylinder 2. Moreover, since the weight 9 is provided in order to bias the center of gravity of the writing instrument, it may be continuously provided in the axial longitudinal direction or may be provided at an appropriate interval. Further, there is no limitation on the number of weights to be deployed, and FIG. 1 shows an example in which two weights are symmetrically disposed on both sides of the axis X.

  The weight 9 is fixed to the inner surface of the shaft tube 2 so as not to move in the shaft tube 2 of the writing instrument 1. Examples of the fixing method include adhesion with an adhesive, fusion between materials, engagement, and fitting.

  When the weight 9 is fixed to the inner surface of the shaft cylinder 2 and deployed, regardless of the length of the weight, the position of the weight, the method of fixing the weight, and the type and number of writing tool members to be mounted, It must be at the approximate center of the writing instrument's overall length in writing. If the weight is biased, when placed on a desk or the like, it will not roll in a direction perpendicular to the longitudinal direction of the shaft cylinder, and the entire writing instrument will become unbalanced, and the one without the weight will float up. Therefore, it becomes impossible to effectively prevent rolling.

  In writing instruments such as ballpoint pens and mechanical pencils, refills and core tanks are inserted inside the shaft cylinder 2, so if the weight 9 is fixed along the longitudinal axis of the inner surface of the cylindrical shaft cylinder 2, There is no loss of function. When the weight 9 is arranged in the axial longitudinal direction of the inner surface of the shaft cylinder 2, it is desirable to arrange the weight continuously in the axial longitudinal direction as shown in FIG. When the weight cannot be continuously provided on the inner surface of the shaft cylinder 2 due to the mounting of the weight, the weight can be adjusted by arranging a plurality of weights at appropriate intervals. Further, the length of the weight can be appropriately changed depending on the specific gravity of the material constituting the weight. For example, when the weight is made of a material having a high specific gravity, the axis of the inner surface of the shaft tube 2 is centered on the position of the center of gravity. Even if it is arranged in a portion close to the center of gravity of a part in the longitudinal direction, the center of gravity is stabilized, so that the writing instrument can be prevented from rolling.

  The material of the weight is not particularly limited, and for example, a metal such as brass, a plastic kneaded with a high specific gravity filler, or the like can be used. Among these, the metal material is preferable because it is relatively inexpensive and has many types, and it is easy to adjust the position of the center of gravity by adjusting the weight (volume × specific gravity) of the weight by appropriately selecting the type of the metal material. Material.

  The shape of the weight is not particularly limited, and the cross section can be any shape such as a circular shape, a crescent shape, and a bow shape. When a member for a writing instrument such as a refill is mounted, the cross-sectional shape of the weight can be any shape that does not impair the original purpose of the member for a writing instrument such as a refill. Further, when the weight is provided, it is preferable to fix a metal plate or the like having a desired shape on the inner surface of the shaft cylinder using the fixing method in the assembling process of the writing instrument.

  In the rolling preventing writing instrument of the present invention, the material forming the shaft cylinder and various members is not particularly limited, but for the shaft cylinder, for example, ABS resin, polycarbonate resin, polypropylene resin, acrylic resin, polystyrene resin, carbon fiber reinforced plastic, etc. For example, ABS resin, polycarbonate resin, polyacetal resin, etc. are used for various members. The said material is an illustration and resin other than this may be sufficient.

  Next, the relationship between the center of gravity position and rolling of the rolling preventing writing instrument of the present invention will be described. In the present invention, since the center of gravity G of the writing instrument 1 is on a short axis passing through the axis X of the shaft cylinder 2 and deviated from the axis X, the writing instrument 1 sways swayingly and the shaking is attenuated. Move. When the volume of the weight 9 to be deployed is the same, the greater the specific gravity of the weight 9 to be deployed, the lower the position of the center of gravity of the writing instrument (the farther the distance from the axis), the greater the shaking of the writing instrument.

  From the relational expression of momentum (moment) F = m × v (m: mass of writing instrument, v: speed), if the writing instrument is thrown out with a force of 2 (N), the weight is evenly distributed in the axial direction of the shaft cylinder. If present, the same acceleration is applied to the entire writing instrument, so the writing instrument rolls straight. On the other hand, when the weight is biased with respect to the axial direction of the shaft cylinder, the mass is different, so that the writing instrument becomes difficult to roll straight due to a difference in the acceleration of the writing instrument and rolls to the larger mass side. . Therefore, if the weight is at the rear end portion (on the side of the knock member) in the cylindrical shaft tube, it becomes difficult to roll straight and the balance at the time of writing also deteriorates.

Further, as the center of gravity of the writing instrument moves away from the axial center on the short axis, the amplitude cycle in the damping motion of the writing instrument becomes slower. Here, amplitude period T = 2π / ω (ω: angular velocity rad / s) = 2π (d / g) ^1/2 (g: gravitational acceleration 9.8 m / s ² , d: center of gravity position and axis of writing instrument Of the distance mm). Therefore, as the distance (d) between the center of gravity position of the writing instrument and the axis increases, the slow swinging is repeated.

  In the writing instrument (ballpoint pen) 1 of Embodiment 1 shown in FIG. 1, a weight 9 is mounted on the inner surface of a cylindrical shaft cylinder 2 along the longitudinal direction of the axis, and a plurality of other members necessary for a desired ballpoint pen. It has been deployed in a position that does not interfere with. The center of gravity G is substantially at the center of the entire length of the writing instrument 1 and is present at a position offset from the axis X on the short axis passing through the axis X.

  FIG. 2 is a diagram showing a writing instrument (ballpoint pen) 1 according to the second embodiment, except that the cross-sectional shape of the weight 9 is a crescent-shaped shape in which a portion that hinders mounting of other members necessary for the ballpoint pen is removed. This is the same as the first embodiment. When a weight made of the same material as that of the first embodiment is used, the center of gravity is biased to the outside of the shaft tube 2 by the amount of the weight that increases (the weight of the weight increases).

  FIG. 3 is a view showing a writing instrument (ballpoint pen) 1 of Embodiment 3, wherein the weight 9 has a circular cross-sectional shape, and three circular weights 9 are arranged in parallel to the longitudinal direction of the shaft. Except for this, it is the same as in the first embodiment.

  FIG. 4 is a diagram showing the writing instrument (ballpoint pen) 1 according to the fourth embodiment. The writing instrument 1 rolls on the desk or the like at the rear end of the writing cylinder in the vicinity of the knock member 7 of the writing instrument shown in the first embodiment. A rolling stopper 10 is provided as an auxiliary member for preventing the above.

  Although not shown, in the writing instrument (mechanical pencil) of the fifth embodiment, a core tank connected to a chuck is mounted in a cylindrical shaft tube, and a core holder, an eraser, and the like are mounted. Also in this embodiment, a weight is fixedly provided in the axial longitudinal direction on the inner surface of the cylindrical shaft cylinder at a position that does not hinder the mounting of the writing instrument member necessary for the mechanical pencil. The shape of the weight may be the form shown in the first to third embodiments or other forms. As shown in Embodiment 4, a rolling stop can also be provided.

  In the above embodiment, a general writing instrument member not shown or described, for example, a gripping member formed of rubber or elastomer may be mounted.

  In the embodiment according to the present invention, the knock type ball-point pen has been described as an example of the writing instrument. However, the present invention is not limited to the type and material of the member to be mounted. Further, the same can be applied to a knock-type writing instrument having a different structure, a multi-color writing instrument, a compound writing instrument equipped with a ballpoint pen refill and a mechanical pencil lead tank. Moreover, although it can implement also with a cap type writing instrument, in the case of a cap type writing instrument, a gravity center position is calculated in the state which fitted the cap to the front-end | tip part.

  The writing instrument of the present invention can be applied to a writing instrument in which various members are mounted on a cylindrical shaft such as a ballpoint pen, a mechanical pencil, a marker, and a correction pen.

DESCRIPTION OF SYMBOLS 1 Writing instrument 2 Shaft cylinder 3 Refill 4 Projection part 5 Rotating cam 6 Fixed cam 7 Knock member 8 Tip part 8a Tip opening part 9 Weight 10 Anti-rolling X Shaft center G Center of gravity

Claims (2)

A writing instrument not having a clip in which a plurality of writing instrument members are mounted in a cylindrical shaft cylinder,
The center of gravity of the writing instrument is located at the approximate center of the entire length of the writing instrument that is not in a writing state, and at a position deviated from the axis of the shaft cylinder,
A writing instrument, wherein a weight is fixedly disposed on an inner surface of the shaft tube in a longitudinal direction of the shaft.   The writing instrument according to claim 1, wherein the writing instrument moves in such a manner that the shaking in the axial short direction is attenuated.