JPH0624234Y2 - Writing instrument - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a writing instrument that can sequentially feed an eraser from the rear end of the writing instrument, and more particularly to a writing instrument that can be easily assembled.

(Prior Art and its Problems) In order to increase the amount of eraser attached to a writing instrument, various proposals have been made as a writing instrument in which a long eraser housed in the writing instrument body can be sequentially fed out.

For example, as in Japanese Utility Model Laid-Open No. 57-132598, a spiral groove formed on the inner surface of the rear shaft is engaged with a protrusion of a substantially cylindrical eraser receiver protruding from a slit provided in the core tank to rotate the rear shaft. The eraser can be drawn out by moving it.

When the eraser receiver is inserted into the eraser guide member (the core tank in the above example), the above-mentioned one guides the protrusion of the eraser receiver to the slit and inserts it from the rear end. However, in such a case, since the eraser guide member divided by the slit provided up to the rear end of the eraser guide member has relatively free elasticity inward and outward, this occurs when the eraser is used. Also, the eraser receiver may fall from the rear end of the slit. Therefore, it is conceivable that another member is externally fitted and fixed to the rear end of the slit after the eraser receiver is inserted, but this is not preferable because it leads to an increase in cost. Therefore, there are some slits that are stopped halfway without being provided to the rear end. This is one in which the width of the slit is made wider than the outer diameter of the eraser receiver, or the eraser receiver is formed smaller so that the eraser receiver is inserted from the slit. There may be rattling, the non-slit part may be thin, and the strength may decrease, causing breakage during rotation, etc.If the eraser receiver is smaller than the slit, play between the eraser receiver and the eraser guide member after insertion. However, there is still room for improvement in inserting the eraser receiver into the eraser guide member, such as the occurrence of backlash.

(Purpose) It is an object of the present invention to provide a writing instrument in which the eraser receiver can be easily inserted without widening the width of the slit provided in the eraser guide member and the play when using the eraser is suppressed as much as possible. .

(Means for Solving the Problems) The present invention is directed to an eraser receiver having a spiral member having a spiral groove, an eraser guide member having a slit in the longitudinal direction, and a protrusion slidably arranged in the eraser guide member slit. In the writing instrument having, the non-slit portion of the eraser guide member is deformably formed, the non-slit portion is deformed, and the slit portion is expanded so that the eraser receiver can be inserted. The writing object is characterized by connecting both ends of the above, and the object is to meet the above object.

(Operation) In the present invention, since the non-slit portions on both sides of the slit of the eraser guide member are deformable, the eraser receiver can be inserted while expanding the non-slit portion outward even if the width of the slit is small. , After the insertion, return to the normal state and hold the eraser receiver.

(Embodiment) Hereinafter, a more detailed description will be given based on an embodiment shown in the accompanying drawings. The left side in the figure is the front and the right side is the rear.

FIG. 1 shows an example in which the present invention is applied to a mechanical pencil, and a tip metal 3 having a known core detent member 2 is screwed on the front of a barrel 1. Further, a core tank 5 having a chuck 4 continuously provided at the tip is provided inside the shaft cylinder 1, and a knock spring S is interposed between the core tank 5 and the shaft cylinder 1, and the front of the chuck 4 is provided. The chuck ring 6 is slidably fitted on the outside. Reference numeral 7 is a spiral member having a spiral groove 7a, which is non-rotatably fitted between the barrel 1 and the core tank 5 (see FIG. 1-B) and is divided by the slit 8a and the slit 8a in the longitudinal direction. The eraser guide member 8 having a deformable non-slit portion 8b is held by the rear end flange portion 8c and the press-fitting member 9 for preventing looseness of the eraser provided on the eraser guide member 8 and for preventing disassembly of the eraser feeding mechanism. It is rotatably arranged with respect to. An eraser receiver 11 having a gripping portion 11b for holding and fixing the eraser 10 is inserted into the eraser guide member 8, and the eraser receiver 11 allows the protrusion 11a to be exposed from the slit 8a of the eraser guide member 8 and the spiral member 7 Is engaged with the spiral groove 7a.

An assembling method based on the above configuration will be described.

FIG. 1 illustrates a so-called knock-type mechanical pencil in which the mechanical pencil mechanism part and the eraser feeding mechanism part in the rear part can be separated from each other in the front part, but since the front part is a general mechanical pencil mechanism, it is in the rear part. The eraser feeding mechanism will be described.

First, the eraser receiver 11 is inserted from the slit 8a of the eraser guide member 8 so as to be pressed against the slit 8a. At this time, since the non-slit portions 8b on both sides of the slit 8a are deformable, as shown in FIG. It can be easily inserted by expanding outward. Further, as shown in FIG. 3, if the edge 12 of the non-slit portion 11b is chamfered, the insertion can be performed more smoothly. Further, the protrusion 11a of the eraser receiver 11 may be chamfered at the contact portion with the non-slit portion such as the grip portion 11b. Eraser holder 1 after insertion
1 is held by the return of the slit portion 8b to the normal state, and is slidably arranged in the eraser guide portion 8. Next, the spiral member 7 is inserted from the front of the eraser guide member 8 until it comes into contact with the collar portion 8c, and the press-fitting member 9 is further press-fitted from the front of the eraser guide member 8. As a result, the spiral member 7 is rotatably fixed by the press-fitting member 9 and the flange portion 8c. Finally, the eraser 10 is press-fitted and fixed to the eraser receiver 11.

In the present invention, the eraser guide member 8 has two slits 8a and the eraser receiver 11 has two protrusions 11a. However, at least one of these is essential.

(Effect of the Invention) According to the present invention, since the non-slit portions on both sides of the slit provided in the eraser guide member are deformable, the non-slit portion is expanded outward when the eraser receiver is inserted into the eraser guide member. The eraser receiver can be easily opened and placed in the eraser guide member. At that time, since the non-slit portion returns to the normal state and holds the eraser receiver, it is possible to provide a writing instrument that prevents play when using the eraser as much as possible.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the present invention, wherein FIG. 1-A is a longitudinal sectional view, FIG. 1-B is a sectional view taken along line AA of FIG. 1-A,
Fig. 2 is an external view of the non-slit part of the eraser guide member when it is expanded outward, and Fig. 3 is a cross-sectional view taken along line BB of Fig. 2 when the non-slit part is returned to the normal state. It is the figure given. 7 ... spiral member, 7a ... spiral groove, 8 ... eraser guide member,
8a ... slit, 8b ... non-slit portion, 10 ... eraser, 11 ... eraser receiver, 12 ... edge

Claims (2)

[Scope of utility model registration request] 1. A writing instrument having a spiral member having a spiral groove, an eraser guide member having a slit in the longitudinal direction, and an eraser receiver having a protrusion slidably arranged in the slit of the eraser guide member, The non-slit portion of the eraser guide member is formed to be deformable, the non-slit portion is deformed so that the slit portion expands so that an eraser receiver can be inserted, and both ends of the slit portion are connected. Writing instrument to be. 2. The writing instrument according to claim 1, wherein the edge of the non-slit portion and / or the contact portion of the eraser receiver with the non-slit portion is chamfered.