Sharp pencil

Abstract

The present invention mainly aims to improve learning efficiency by enabling primary and junior high school students to learn with free thinking. Compared with a pencil, which has a relatively simple structure, a mechanical pencil that holds a mechanism for pushing out the refill and is sized to be easy to hold by a person is subject to strong constraints on the size of the mechanism, and thus there is a tendency to consider improving the mechanism. However, the most important thing is that it is easy for the user to hold, fits well in the hand, and allows writing or drawing. 【Means for Solving the Problem】The object of the present invention is to improve the stability and feel of holding of a mechanical pencil. The cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder is substantially line-symmetric with respect to a line segment passing through the center of the cross-section, and along the longitudinal axis of the mechanical pencil, the cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder changes at a certain ratio. It is a pencil characterized by this shape, enabling efficient learning and work from children to adults.

Description

Technical Field

[0001] The present invention relates to a sharp pencil.

Background Art

[0002] Conventionally, sharp pencils have been widely used in schools such as elementary schools, junior high schools, senior high schools, and universities, offices, or each household. In particular, when elementary school students to university students study, there is a demand for sharp pencils that can be used efficiently for study.

[0003] Adults and working people have a lot of computer-related work and tend to use various pens rather than sharp pencils. However, not only those engaged in drafting work such as architects but also many people who prefer handwriting, and the role of sharp pencils is significant. When writing or drawing, lower-grade elementary school students often use pencils, and the number of people using sharp pencils tends to increase from the upper grades of elementary school.

[0004] After junior high school, students tend to prefer sharp pencils with thin leads that are always sharp over pencils. For upper-grade elementary school students to junior high school students, who are in a period of solidifying the basic postures of learning, the presence of sharp pencils in learning is extremely significant both at school and at each household.

[0005] Various sharp pencils mainly having a lead feed mechanism that stores a writing lead of about 0.5 mm and has a chuck for holding the writing lead, a spare lead storage section, etc. are mainly used when studying by oneself at schools such as elementary schools, junior high schools, senior high schools, and universities, or in libraries or at home, and there are many sharp pencils improved so that they can be used efficiently.

[0006] For those who study using a mechanical pencil with a thin refill that is more prone to breakage than a regular pencil, there is a tendency to prefer mechanical pencils with refills that are less likely to break. Especially for those with a strong writing pressure, the fact that the strong writing pressure causes the refill to break frequently during study or exams is a major drawback. Therefore, it is important that the refill is less likely to break, and mechanical pencils equipped with a refill break prevention mechanism (hereinafter referred to as "mechanical pencils with a refill break prevention mechanism") have been developed, and for example, Patent Document 1 is known.

[0007] The mechanical pencil with a refill break prevention mechanism has a mechanism that makes the refill less likely to break when excessive writing pressure is applied, which is preferable for users. However, because the mechanism is complex, the likelihood of failure of the mechanical pencil body increases, so it is not necessarily efficient for users.

[0008] When using a mechanical pencil with a retractable refill, it is preferable to have more spare refills. There are improvements in the cross-sectional shape of the spare refill storage part, etc., and mechanical pencils that increase the number of spare refills (hereinafter referred to as "mechanical pencils with enhanced spare refill storage parts") have been developed, and for example, Patent Document 2 is known.

[0009] The mechanical pencil with an enhanced spare refill storage part greatly reduces the trouble of changing the spare refill, so it is more efficient for users. However, those who are reluctant to spend the time and effort to change the spare refill are mainly in situations where time is limited, such as during exams. During daily study or work, the task of changing or adding a spare refill is not very troublesome, and the task of adding a spare refill can even lead to a temporary break during study or work. Therefore, although the efficiency does not increase much, it has the aspect of inhibiting concentration.

[0010] In order to reduce the effort of pressing the knocking part to extrude the refill, a knock-type sharp pencil that can feed the writing lead by a shaking operation and a knocking operation has been developed and has been widely used for a long time. The knock-type sharp pencil is compact, has a short stroke, and can be operated with a light force. If a series of shaking operations can be performed, it is convenient for the user with less burden and less collision noise, and a sharp pencil that can be used with a compact operation (hereinafter referred to as "compact shaking type sharp pencil") has been developed, and for example, Patent Document 3 is known.

[0011] Since the compact shaking type sharp pencil has improved important points for the user, it has improved the efficiency of use. However, for the user, the act of "writing or drawing" takes longer than the act of "shaking out the lead", and the important point for the user is the latter. When considering the use efficiency of the sharp pencil, the ease of writing or drawing should be emphasized.

[0012] Against this background, there is an expectation for the emergence of a new sharp pencil that is different from the sharp pencil with a lead break prevention mechanism, the sharp pencil with enhanced spare refill storage part, and the compact shaking type sharp pencil, which can be used by a wide range of people from children to adults, is easy to hold, has a strong writing pressure and is easy to write, and is more conducive to concentrating on learning and work, and is efficient and simple.

Prior Art Documents

Patent Documents

[0013]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0014] The present invention has been made in view of the above circumstances, and an object thereof is to provide a sharp pencil that is easy for a user to write or draw, fits comfortably in the hand, and can improve learning efficiency and work efficiency.

[0015] The present invention mainly aims to improve learning efficiency by enabling primary and junior high school students to learn with free thinking when studying. With the advent of the Internet society, the learning method of primary and junior high school students searching on a notebook computer or the like and inputting information into the notebook computer has increased, and the opportunity to write or draw by hand has decreased. In this social environment, an object of the present invention is to provide a sharp pencil that allows primary and junior high school students to efficiently learn while feeling the pleasure of writing or drawing by hand.

[0016] Compared with a pencil having a relatively simple structure, a sharp pencil that holds a mechanism for pushing out a refill and needs to be of a size that is easy for a person to hold is subject to strong constraints on the size of the mechanism. Although there is a tendency to consider improving the mechanism, the most important thing is that the user can hold it easily, it fits comfortably in the hand, and the user can write or draw.

Means for Solving the Problems

[0017] An object of the present invention is to improve the stability and grip feeling of a sharp pencil. The cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder is a shape that is substantially line-symmetric with respect to a line segment passing through the center of the cross-section. Along the longitudinal axis of the sharp pencil, the cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder changes at a certain ratio. It is a pencil characterized by this shape, and can be used efficiently for learning and work from children to adults.

[0018] The cross-sectional shape in the longitudinal axis direction of the shaft cylinder is not particularly limited as long as it is a shape that is substantially line-symmetric with respect to the center of the cross-section, such as a general circular shape or a regular hexagonal shape.

[0019] The corners of the cross-sectional shape in the longitudinal axis direction of the shaft cylinder preferably have rounded edges.

[0020] The surface finish of the shaft tube is preferably wooden, inheriting the feel of using a pencil.

[0021] When the surface finish of the shaft tube is wooden, the paint on the surface of the shaft body is preferably paint that can feel the texture of wood as much as possible.

[0022] The surface finish of the shaft tube can also be considered separately from a pencil. In that case, it is preferably a soft material such as rubber that is gentle on the hand and fits well.

[0023] The shaft tube composed of the front shaft, rear shaft, and connecting part tends to have cuts or lines between the respective parts from the mechanism of a mechanical pencil. However, these cuts or lines are preferably as inconspicuous as possible.

[0024] The shaft tube composed of the front shaft, rear shaft, and connecting part is preferably such that the front shaft and the rear shaft are integrated.

[0025] The knock cover is preferably the same as or similar to the surface finish of the shaft tube.

[0026] The rate of change of the cross-sectional shape perpendicular to the vertical axis of the shaft tube at a certain rate is preferably about 15% to 20%.

Advantages of the Invention

[0027] According to the present invention, due to the cross-sectional shape of the shaft body changing at a certain rate in the longitudinal axis direction, it is easy to hold, fits well with the hand and fingers, and a new mechanical pencil can be realized.

Brief Description of the Drawings

[0028]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

MODE FOR CARRYING OUT THE INVENTION

[0029] An embodiment of the present invention will be described with reference to the drawings. Specific examples of the embodiments of the present invention are not limited to the following embodiments and examples. Also, for easy understanding of the description, the same parts and members in the drawings are given the same numbers.

[0030] FIG. 1 and FIG. 2 show a pencil according to this embodiment. FIG. 1 shows a perspective view of this embodiment, FIG. 2(a) shows a plan view, (b) shows a bottom view, and FIG. 3 shows a side view. In this embodiment, the cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder is a circle, and it decreases at a constant rate along the longitudinal axis from the spare lead storage part toward the chuck direction, so it has a shape that is easy to fit in the hand and fingers.

[0031] Specific configurations of other parts can be variously modified without departing from the gist of the present invention.

EXAMPLE

[0032] Example 1 As an example, Example 1 of the present invention will be described with reference to the drawings. FIG. 4 shows a perspective view of Example 1, FIG. 5(c) shows a plan view, (d) shows a bottom view, and FIGS. 6(e) and (f) show side views. The cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder in Example 1 is a hexagon, and it decreases at a constant rate along the longitudinal axis from the spare lead storage part toward the chuck direction, so it has a shape that makes it easy to apply force toward the tip pipe when holding and writing or drawing the shaft cylinder.

[0033] Example 2 As an example, Example 2 of the present invention will be described with reference to the drawings. FIG. 7 shows a perspective view of Example 2, FIG. 8(g) shows a plan view, (h) shows a bottom view, and FIGS. 9(i) and (j) show side views. The cross-sectional shape perpendicular to the longitudinal axis of the shaft cylinder in Example 2 is an equilateral triangle with rounded corners. The feel when held is quite different from that of a circle or a regular hexagon. Since the smoother surface is larger, many people prefer this shape. It is difficult to roll and has a simple and easy-to-use shape.

Industrial Applicability

[0034] The mechanical pencil according to the present invention can be widely applied to all fields of daily life, such as a writing instrument when widely studying from elementary school students to university students or graduate students, or a writing instrument when a working person studies or works.

Explanation of Reference Numerals

[0035] 1 ··· Mechanical pencil 11 ··· Shaft cylinder 12 ··· Front shaft 13 ··· Rear shaft 14 ··· Tip pipe 15 ··· Mouth tip member 16 ··· Knock cover 21 ··· The longitudinal axis that is the same as the direction of the shaft cylinder and passes through the center of the planar shape of the shaft cylinder

Claims

1. A mechanical pencil comprising: a shaft tube; a lead feed mechanism disposed within the shaft tube and having a chuck for holding a writing lead; an operating portion for moving the chuck forward; and a spare lead storage portion that is interlocked with the chuck and stores a spare writing lead, wherein a cross-sectional shape perpendicular to the longitudinal axis of the shaft tube is substantially line-symmetric with respect to a line segment passing through the center of the cross-section, the cross-sectional shape is a conical shape that decreases at a constant rate along the longitudinal axis in a direction from the spare lead storage portion toward the chuck, and is substantially similar to the cross-sectional shape of the bottom surface of the shaft tube. At a portion where a tip member having a conical shape contacts a front shaft, a circle of the cross-section of the tip member is inside a figure of the cross-section of the front shaft.

2. The mechanical pencil according to claim 1, wherein a cross-sectional shape perpendicular to the longitudinal axis of the shaft tube is substantially a regular hexagon.

3. The mechanical pencil according to claim 1, wherein a cross-sectional shape perpendicular to the longitudinal axis of the shaft tube is substantially an equilateral triangle.

Images