JP2513680Y2 - Writing instrument - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) A writing instrument in which a pen tip portion of a replaceable refill is projected from a tip of a shaft, and a spring for urging the refill forward is arranged at the inner bottom of the shaft. Regarding Here, as an example of the writing instrument, a ballpoint pen, a small tube type writing instrument, a resin pen, an eyeliner, a lip color and the like can be exemplified.

(Prior Art) In a writing instrument in which a pen tip portion of a replaceable refill is projected from a tip of a shaft, in order to stabilize the projection of the pen tip portion, the refill is urged forward to the inner bottom portion of the inner hole of the shaft. Often have springs.

Also, in that case, in order to prevent the spring from coming off during replacement of the refill, for example, by forming a spring press-fitting part in the inner bottom part of the shaft or using an adhesive, the spring is generally fixed. It is fixedly arranged.

(Problems to be Solved by the Invention) As described above, when the spring is fixedly arranged, it is fixed in the inner bottom portion of the inner hole of the shaft, and therefore, except in a special case where the shaft is transparent. However, it is extremely difficult to confirm whether or not it has been securely fixed as desired.

In addition, in the case of press-fitting, insufficient press-in force may occur due to variations in molding dimensions, and when the material of the shaft is synthetic resin or the like, insufficient press-in force may occur due to plastic deformation over time after fixing. .

Therefore, an object of the present invention is to provide a spring that can be easily confirmed for fixing and that has a high reliability for fixing the spring.

(Means for Solving the Problem) The present invention provides a writing instrument in which a pen tip portion of a replaceable refill is projected from a tip of a shaft, and a spring for urging the refill forward is arranged at the inner bottom of the shaft inner hole. A plurality of radial ribs that partially reduce the diameter of the inner hole are formed in the inner bottom portion of the inner hole of the shaft, and the radial rib has a convex portion, and a spring is press-fitted between the radial ribs. The gist is a writing instrument in which the convex portion is positioned between spring lines and the spring is locked.

(Example) An example is shown in the attached FIG. 1 and FIG. The reference numeral A is a refill. It has a nib portion 1 in which a small tube nib, a resin nib obtained in a thin wire shape by extrusion molding, a ball-point pen body using a chip made of a metal pipe, etc. are drawn in consideration.

Reference numeral B indicates a shaft, which is composed of a front shaft 2 and a rear shaft 3 which are detachably engaged with each other. Front axis 2
Protrudes the pen tip portion 1 of the refill A from the tip opening 4, but of course prevents the refill A from falling off,
In the illustrated example, the front shaft 2 and the refill A are fitted at the tip opening 4. Further, as shown in an enlarged manner in FIG. 2, the rear shaft 3 has an appropriate number (four cases are shown) of ribs 7 on the inner bottom portion 6 of the inner hole 5. The rib 7 serves as a press-fitting portion of a spring 8 that biases the refill A forward, and except for a tapered tip portion 9 for facilitating the insertion of the spring 8, mutual ribs (inscribed The diameter of the circle) is made somewhat smaller than the outer shape of the spring 8 in the free state. That is, in the illustrated state, the spring 8 is inserted between the ribs 7 in a deformed state. Furthermore,
Each rib 7 is formed with a convex portion 10 having an appropriate shape, and the convex portion 10 is located between the spring wires (the wire material forming the spring 8). Therefore, the spring 8 is inserted over the convex portion 10. In the figure, the spring wire is in contact with one of the protrusions 10 (the one on the upper side of the drawing), but it is only shown that the protrusions 10 compensate for insufficient press-fitting. And it doesn't have to be in constant contact. Further, although the reference numeral C is a cap, it is not included in the gist of the invention, and the description thereof is omitted.

Although illustration is omitted, various modifications other than those illustrated above can be made. For example, although the shaft is composed of a front shaft and a rear shaft that are detachably screwed with each other, they can be detachable from each other by fitting with a recess and protrusion. Also,
The refill is supposed to fit at the front end opening of the front shaft, but a step is formed inside the front shaft, and the refill biased forward by the spring abuts against this step. You can also prevent the refill from falling off by doing so. Furthermore, rather than front and rear shafts, if the refill can be replaced, such as the one in which the front body is removably attached to the tip of the shaft body, it is possible to select from an appropriate number of parts with appropriate shapes. It can also be Materials such as metal and synthetic resin are also appropriate. Also, for example, for refills, a structure like a fountain pen that contains ink in a raw ink state and temporarily stores ink is used to prevent ink leakage,
It is appropriate to use a fiber bundle such as one that absorbs ink by capillary force, or a valve structure. The pen tip may be of a type other than the above. Further, for example, as the press-fitting portion, the inner diameter of the inner bottom portion of the inner hole of the shaft may be slightly smaller than that of the spring without forming a rib. Further, instead of using the inner wall for press-fitting so that the spring is inserted, the outer wall may be used for press-fitting so that the spring is inserted. As an example, a columnar portion having a gentle tip protruding forward is formed in the center of the inner bottom portion of the inner hole, and a spring is inserted therein. The convex portion will be formed on the outer wall of the columnar portion. The number and shape of the convex portions, the formation position, and the like are also appropriate. In addition, the pitch of the spring and the number of turns are also appropriate.

(Effect of the Invention) The writing instrument of the present invention is a writing instrument in which the pen tip portion of the replaceable refill is projected from the tip of the shaft, and a spring for biasing the refill forward is arranged at the inner bottom of the shaft inner hole. A plurality of radial ribs that partially reduce the diameter of the inner hole are formed in the inner bottom of the inner hole, and the radial rib has a convex portion. The part is located between the spring wires and this spring is locked.When fixing the spring, it is easy to check whether the spring can be fixed as desired by the feel when riding over the convex part. Moreover, since the convex portion compensates for variations in molding dimensions and insufficient press-in force due to plastic deformation over time after fixation, the reliability of fixation can be high.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of the present invention, and FIG. 2 is an enlarged view near the inner bottom portion of the inner hole of the shaft in FIG. A ... Refill, B ... Shaft, C ... Cap, 1 ... Pen tip part, 2 ... Front shaft, 3 ... Rear shaft, 4 ... Tip opening part, 5 ... Inner hole,
6 ... bottom part, 7 ... rib (an example of press-fitting part), 8 ... spring, 9 ... rib tip part, 10 ... convex part.

Claims (1)

(57) [Scope of utility model registration request] 1. A writing instrument in which a pen tip portion of a replaceable refill is projected from a tip of a shaft, and a spring for urging the refill forward is arranged at a deep bottom portion of the shaft inner hole. A plurality of radial ribs that partially reduce the diameter of the inner hole are formed, and the radial ribs have convex portions, and the convex portions are arranged between the spring wires while press-fitting a spring between the radial ribs. Writing instrument made by locking this spring at the position.