JPH0720752B2 - Writing instrument cover and movement stop of the cover - Google Patents

Description

TECHNICAL FIELD The present invention relates to a writing instrument cover for covering a shaft of a writing instrument such as a ballpoint pen and a mechanical pencil, and a structure for preventing movement of the coating.

<Conventional technology> Conventionally, the shaft diameter of ballpoint pens, mechanical pencils, etc. is approximately 7 m
The cross-sectional shape was m or 8 mm, and most of them were circular or polygonal.

Further, among these, there are some which use a relatively soft material for the gripped portion which the finger touches, but most of the above-mentioned writing instruments have a Shore A hardness of around 100 degrees.

<< Problems to be Solved by the Invention >> Most of conventional writing instruments have a shaft diameter of 7 to 8 mm. When writing with a writing instrument having such a shaft diameter, a large gripping force is required so that the writing instrument does not slip. In particular, in writing with a ballpoint pen, a writing pressure of 2 to 3 times that of a pencil is required to eject ink. Therefore, the ballpoint pen is firmly held by the thumb, forefinger and middle finger.

As a result, when the writing operation is continued for a long time, the hardness of the pen shaft is high, and the finger becomes painful at the portion in contact with the pen shaft, which causes fatigue. When this fatigue is accumulated, phenomena such as tendonitis, which are unfavorable to occupational health, occur.

The present invention has been devised to solve such a problem, and by mounting a covering made of a soft elastic material on a writing instrument, the contact area hit by a finger is increased and the frictional resistance of the grip portion is increased. The purpose is to increase the grip to reduce the gripping force and reduce fatigue during writing work.

<< Means for Solving the Problem >> The present invention is a covering for a writing instrument, which uses a soft elastic material such as rubber or synthetic resin, and has a Shore A hardness of 40 to 60 degrees. Furthermore, a covering body having a diameter of 10.5 mm to 14.3 mm after being attached to the writing instrument is provided, and the covering body is attached over almost the entire length of the writing instrument. It is preferable that silicon rubber is used as the material of the cover and the thickness thereof is 1 mm to 3 mm. Further, the object is achieved by making the outer diameters of the end portions of the front and rear end body pressing members on the side of the covering body equal to the outer diameter of the covering body.

<< Example >> Example 1 The Example of this invention is described based on drawing.

The writing instrument cover of the present invention has a structure shown in FIGS. 1 and 2.

FIG. 1 is a cross-sectional view showing a writing instrument cover of the present invention,
FIG. 2 is a side view showing an embodiment in which the covering body of the present invention is attached to a pen body. In FIGS. 1 and 2, a cover 1 made of a soft elastic material such as rubber or synthetic resin is formed. The thickness of the cover 1 is suitably 1 mm to 3 mm. The thickness of the covering 1 is set to 1 mm to 3 mm and the soft elastic body is used as the material in consideration of the improvement of frictional resistance and the feel at the time of gripping. The cover 1 is a tubular body, and is attached over substantially the entire length of the pen body 5. Further, at one end on the pen tip side, a diaphragm portion 4 is provided for both the visibility of the pen tip and the non-slip of the pen body 5. The second
As shown in the figure, a grip portion 2 having irregularities for preventing slippage is provided on the rear end side outer periphery from a portion where the covering body 1 on the rear end side of the narrowed portion 4 is parallel, as required. This grip 2
Is generally supported by the thumb, forefinger, and middle finger, but considering that the support site differs depending on the writing instrument,
The length should be 25 to 30 mm. Further, the inner diameter of the hollow portion 3 needs to be the same as or slightly smaller than the outer diameter of a ready-made ballpoint pen, mechanical pencil or the like to prevent sliding of the writing instrument within the covering body. Next, a test was conducted on 12 female clerks using a pencil-shaped ballpoint pen equipped with a covering having a Shore A hardness of 50 degrees having various outer diameters according to the present invention.

Of the 12 subjects, 7 had strong gripping force (the index finger bends inward and the tip of the thumb touches the index finger strongly and presses it strongly) when writing with a standard size (diameter 8.2 mm) ballpoint pen. There are 3 people with strong gripping force (the index finger bends inward) and 2 people with normal gripping force (the index finger bends straight or outward).

The outer diameter of the covering used in the test after being mounted on the ballpoint pen was 3 levels shown in Table 1, and a commercially available ballpoint pen was used as a comparative product.

As a test method, the electromyography of the ball of the foot was used, and 12 subjects tested each size twice, a total of 8 times, and a total of 96 times.

The results are shown in FIG. As can be seen from FIG. 4, the group with particularly strong gripping force has a large difference in amplitude ratio from the standard size ballpoint pen, and the group with normal gripping force shows a slight but opposite tendency. .

This means that the standard size product on the market is most suitable for people with normal gripping force, and for people with strong gripping power, using a ball-point pen with a large outer diameter does not require excessive force on the fingers. It means to say.

Regarding the EMG average amplitude ratio of the size of 13.8 mm and the standard size among the coverings of the present invention, as shown in FIG. 4, a person with a strong gripping force has a strong gripping force of 32%. It can be seen that for humans, there is a 10% reduction in gripping force.

Note that this embodiment is intended for adults, and it is desirable to use a relatively small diameter for persons with small fingers such as children. Further, as a material, a rubbery material having a Shore A hardness of 40 to 70 degrees and a size of 13.8 mm were adjusted for an ebonato at 100 degrees, and a feel test was conducted.
As a result, those having a hardness of 40 to 60 degrees had good touch and non-slip properties.

From the above, about 80% of all people have a gripping force of more than strong
Together with the reality occupying the above, the outer diameter after coating the writing instrument cover of the present invention on a writing instrument such as a ballpoint pen is 10.5 mm.
To 14.3 mm, the material hardness is Shore A hardness
It turned out that the optimum one is 40 to 60 degrees.

The unevenness for preventing the grip portion 2 of the cover body shown in FIG. 2 from slipping may be necessary depending on the material, but is not particularly limited.

Example 2 Silicon rubber was used as the material for the cover 1 shown in FIGS. 1 to 3. The Shore A hardness of this silicone rubber was about 50 degrees, the feel was good, and the friction resistance was large, so there was no slippage of the fingers and a comfortable usability was obtained.

Example 3 FIG. 3 is a sectional view showing a detent structure for a cover,
As shown in FIG. 3, the outer diameters of the tip core retainer 7 and the rear core retainer 8 for fixing the core 6 on the side of the cover body 1 are set to the pen body 5
The outer diameter of both ends of the covering body 1 covered with the pen body 5 is made equal, and the pen body 5 is attached to the pen body 5 via the tip screw 9 and the rear end screw 10 at both ends of the pen body 5.

<Operation> When coating the writing instrument cover of the present invention on a ballpoint pen or the like, among several types of coatings prepared in advance,
A small amount of water is applied to the inside of the covering body 1 or the pen body that matches the diameter of the pen shaft to be used, and the tip of the pen shaft is inserted from the rear end of the covering body 1 as the leading end.

Alternatively, the pen body 5 may be applied with an adhesive and then inserted into the cover body 1, or a small amount of a lubricant such as water may be applied and then inserted into the cover body 1, the tip of which is the tip core holder 7,
By mounting the rear end core body retainer 8, it is possible to prevent the cover 1 from being displaced.

<< Effects of the Invention >> The writing instrument cover of the present invention is a tubular body using a soft elastic material such as rubber or synthetic resin, and the tubular body portion is covered over substantially the entire length of the pen body, and the meat of the coating body is used. The thickness is 1mm to 3mm, and the material of this tubular body is Shore A hardness 4
It is set to 0 to 60 degrees, and when it is attached to a writing instrument such as a ballpoint pen, it has a structure that does not require an excessive gripping force, so that it gives a favorable feeling to the fingers that come into contact with the pen and prevents finger pain. Moreover, the induction of tendonitis is prevented, and in addition, fatigue is reduced.

Especially for adults, an outer diameter of 10.5 mm to 14.3 mm is effective. Further, by using the silicone rubber coating, it is possible to prevent the fingers from slipping, and at the same time, to prevent the fingers from rolling down due to the large friction resistance.

Further, as a movement preventing structure for the covering body, the outer diameter of the covering body side with respect to the tip core pressing member is made equal to the outer diameter of the covering body, and both ends of the covering body are sandwiched so that the covering body is prevented from being displaced. At the same time, there is an effect that the visibility of the pen tip is improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a cover of the present invention, FIG. 2 is a side view showing an embodiment in which the cover of the present invention is attached to a pen body, and FIG. 3 is a sectional view showing a detent of the cover, FIG. 4 is a diagram showing the relationship between the average amplitude ratio of the electromyogram of the thumb and the shaft diameter according to the embodiment of the present invention. 1: Cover, 2: Gripping part, 3: Hollow part, 4: Drawing part, 5: Pen body, 6: Core body, 7: Tip core body retainer, 8: Rear end core body retainer, 9: Tip screw, 10: rear end screw,

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Uto 11-1 Showa-cho, Kure City, Hiroshima Prefecture Junichi Hatai, Inspector, Kure Works, Nisshin Steel Co., Ltd. (56) References: 62-131878 (JP, U)

Claims (4)

[Claims] 1. The outer diameter of the writing instrument attached to the shaft center is
A writing instrument cover made of a soft elastic material made of rubber or synthetic resin having a thickness of 10.5 to 14.3 mm, a Shore A hardness of 40 to 60 degrees, and a thickness capable of elastically deforming effectively for expanding a contact area with a finger. 2. The writing instrument cover according to claim 1, which has a wall thickness of 1 to 3 mm. 3. The writing instrument cover according to claim 1, which is made of silicone rubber. 4. A tip core body retainer and a rear end attached to the shaft center of the writing instrument cover according to any one of claims 1 to 3, which are attached to the axis of the writing instrument. The front body pressing body and the rear end body pressing body have a core body retainer, and the outer diameter of the end portion of the writing instrument cover body side is equal to the outer diameter of the cover body.