JP3704189B2 - Writing instrument shaft - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shaft tube of a writing instrument in which an elastic body is formed on the outer periphery of a grip portion of the shaft tube.
[0002]
[Prior art]
In recent years, writing instruments in which an elastic body is formed on a gripping part in order to prevent finger slipping during writing have become common. Moreover, it is common practice to construct an elastic body by double molding or insert molding on the outer periphery of the gripping portion of the shaft cylinder, from the advantage that it can be configured in productivity and in any shape.
[0003]
[Problems to be solved by the invention]
However, when the elastic body is simply formed by double molding or insert molding on the outer periphery of the gripping portion of the shaft cylinder in which the opening window is formed, there is a problem that the elastic body in the portion adjacent to the opening window is easily peeled off. .
An object of the present invention is to provide a writing cylinder that eliminates the above-described problems.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the shaft cylinder of the writing instrument of the present invention has a groove formed on the outer periphery of the shaft cylinder adjacent to the opening window, and is formed by double molding or insert molding on the outer periphery of the gripping portion of the shaft cylinder. The body is also configured to enter the concave groove. Therefore, even if stress is applied to the elastic body around the opening window, the elastic body is firmly fixed by the concave groove, so there is no fear of peeling off.
[0005]
【Example】
The shaft cylinder of the writing instrument of the present invention will be described with reference to the drawings. 1 and 2, the gripping portion 1A of the shaft tube 1 is formed to be slightly narrowed, and an opening window 1B is formed in the gripping portion 1A. Furthermore, a concave groove 1 </ b> C is formed on the outer periphery of the grip portion 1 </ b> A close to the edges on both sides of the opening window 1 </ b> B of the shaft cylinder 1. A rubber elastic body 2 such as an elastomer is fitted on the outer periphery of the grip portion 1A of the shaft tube 1. The means for externally fitting the elastic body 2 to the shaft cylinder 1 is a so-called two method in which the shaft cylinder 1 is first formed by injection molding a synthetic resin such as ABS, and then the elastic body 2 is injection-molded into the grip portion 1A of the shaft cylinder 1. Perform by heavy molding. Alternatively, the elastic body 2 is formed on the grip portion 1A of the shaft tube 1 by insert molding. At this time, the elastic body 2 is formed so as to also enter the concave groove 1 </ b> C of the shaft cylinder 1.
Therefore, the elastic body 2 in a portion close to the opening window 1B is firmly fixed, and there is no fear that the elastic body 2 is peeled off even if stress is applied to the elastic body 2 in this portion.
[0006]
FIG. 3 shows another embodiment of the shaft cylinder of the writing instrument according to the present invention. A groove 101C is formed on the outer periphery of the gripping portion 101A of the shaft cylinder 101 in the vicinity of the opening window 101B and opposite to the opening window 101B. A concave groove 101D is also formed on the side. Therefore, the elastic body 102 formed in the grip portion 101A of the shaft cylinder 101 enters not only the concave groove 101C adjacent to the opening window 101B but also the concave groove 101D located on the opposite side of the opening window 101B, and the elastic body 102 There is no fear of peeling or wrinkling on one side.
[0007]
FIG. 4 further shows another embodiment of the shaft cylinder of the writing instrument according to the present invention. A groove 201C is formed on the outer periphery of the gripping portion 201A of the shaft cylinder 201 in the vicinity of the opening window 201B. Protrusions 201 </ b> E extending in the longitudinal direction at equal intervals in the circumferential direction are formed. An elastic body 202 is formed in the gripping portion 201A of the shaft cylinder 201, and the elastic body 202 not only enters the recessed groove 201C adjacent to the opening window 201B but also wraps the protrusion 201E of the shaft cylinder 201. Therefore, the elastic body 202 is firmly fixed to the gripping portion 201A of the shaft tube 201 without being peeled off or displaced.
[0008]
The shaft cylinder of the writing instrument of the present invention described above can be used for any writing instrument as long as it is a writing instrument that requires an opening window in the shaft cylinder.
[0009]
Next, an embodiment in which the shaft cylinder of the writing instrument of the present invention is used in a side knock type mechanical pencil will be described with reference to FIGS. 5, 6, 7 and 8. A base 5 containing a core holder 4 that holds the core 3 lightly is screwed into the front portion of the shaft cylinder 1 described with reference to FIGS. 1 and 2. Further, the connecting tool 6 is held by the front end 1 </ b> F of the barrel 1 and the inner stage 5 </ b> A of the base 5. A fastening ring 7 is loosely fitted between the connector 6 and the locking step 5B of the base 5, and the fastening ring 7 is externally fitted to the head 8 </ b> A of the chuck 8. A chuck holder 9 is fixed to the rear part of the chuck 8, and the chuck 8 is urged rearward in the longitudinal direction by a spring 10 stretched between the connector 6 and the outer stage 9 </ b> A of the chuck holder 9. The chuck 8 urged rearward by the spring 10 is pressed and closed by the tightening ring 7 to hold the core 3 firmly. As shown in FIG. 6, the opening button 1 </ b> B of the shaft tube 1 is inserted while the foot portion 11 </ b> A of the side button 11 having a U-shaped cross section is bent, and the side button 11 is attached to the opening window 1 </ b> B of the shaft tube 1. The side button 11 is formed of a synthetic resin such as polyacetal. A core tank 12 made of a pipe material is fixed to the chuck holder 9, and the core tank 12 passes through the foot 11 </ b> A of the side button 11 and protrudes from the rear end of the shaft cylinder 1. A cam member 13 is fitted on the outside of the core tank 12, and the foot portion 11 </ b> A of the side button 11 is in contact with the inclined rear end surface 13 </ b> A of the cam member 13. Therefore, by pressing the side button 11, the foot portion 11A of the side button 11 presses the inclined rear end surface 13A of the cam member 13, and the cam member 13 is advanced. When the cam member 13 moves forward, the cam member 13 comes into contact with the outer collar 9B of the chuck holder 9, and the chuck 8 moves forward together with the chuck holder 9 and the lead tank 12 to feed the lead 3. The cam member 13 is formed of a polyamide resin such as nylon 66. A plug 14 with a slotted front portion 14A is detachably attached to the rear end of the shaft tube 1, and the rear portion 14B of the plug 14 projects in a plate shape so that it can be easily held by a finger. Without the stopper 14, the core 2 accommodated in the core tank 12 abuts on an eraser holder 15 described later, and is pressed when the eraser holder 15 is slid in the longitudinal direction to use the eraser 16. The lead 2 may be broken. A narrow diameter portion 1G is formed in the rear portion of the shaft tube 1, and a concave strip 1H extending in the circumference is formed in the small diameter portion 1G. Further, a projection 1J that protrudes rearward from the rear outer stage 1I is formed on the extended line of the opening window 1B on the narrow diameter portion 1G of the shaft cylinder 1. The protrusion 1J is formed by two protrusions 1J inclined at 45 degrees. An inward projection 17A of the rear shaft 17 is fitted into the recess 1H of the shaft tube 1, and the rear shaft 17 is detachably connected to the small diameter portion 1G of the shaft tube 1. Moreover, as shown in FIG. 9, a notch 17B having the same shape as the protrusion 1J of the shaft cylinder 1 is formed at the front end of the rear shaft 17, and the protrusion 1J of the shaft cylinder 1 and the notch 17B of the rear shaft 17 are aligned. As a result, the shaft cylinder 1 and the rear shaft 17 are positioned in the circumferential direction. A sliding groove 17C extending in the longitudinal direction is formed on the rear shaft 17, and a plurality of locking grooves 17D intersecting the sliding groove 17C are formed at equal intervals in the longitudinal direction. As shown in FIG. 10, the eraser holder 15 has an elastic piece 15B formed by two cut grooves 15A extending in the longitudinal direction, and a locking portion 15C protruding rearwardly from the elastic piece 15B. A fixing hole 15E that communicates with the guide groove 15D that is widened rearward is formed. The eraser holder 15 is built in the rear shaft 17 so as to be slidable in the longitudinal direction. In the eraser holder 15, the foot 18A of the operation button 18 inserted from the sliding groove 17C of the rear shaft 17 is guided from the guide groove 15D and fitted into the fixing hole 15E. A long rod-like eraser 16 is mounted in the rear hole 15F of the eraser holder 15. The eraser 16 retreats together with the eraser holder 15 by moving the operation button 18 rearward and protrudes from the rear end of the rear shaft 17, and the locking portion 15 </ b> C of the eraser holder 15 has a locking groove 17 </ b> D of the rear shaft 17. It is fixed by being locked to. In order to immerse the eraser 16 in the rear shaft 17, the operation button 18 is pressed inward, and the operation button 18 is removed with the locking portion 15 </ b> C of the eraser holder 15 removed from the locking groove 17 </ b> D of the rear shaft 17. Is moved forward and the eraser holder 15 and the eraser 16 are advanced.
[0010]
Next, the case where the lead 2 is stored in the lead tank 12 will be described. First, when the rear shaft 17 is turned, the notch portion 17B of the rear shaft 17 is retracted along the inclined projecting portion 1J of the shaft tube 1, and the shaft The inward projection 17 </ b> A of the rear shaft 17 comes off from the recess 1 </ b> H of the tube 1. Therefore, the rear shaft 17 can be easily removed as compared with simply pulling the rear shaft 17 backward. After removing the rear shaft 17, the rear portion 14 </ b> B of the plug 14 protruding like a plate is held and the plug 14 is removed from the shaft cylinder 1. Then, the rear part of the core tank 12 protruding from the rear end of the shaft cylinder 1 appears. The lead 3 is inserted from the rear end of the lead tank 12.
[0011]
In the case of this embodiment, since the elastic body 2 is formed on the grip portion 1A of the shaft tube 1, it is possible to perform comfortable writing without slipping fingers during writing. Moreover, even if a circumferential stress is applied to the elastic body 2 when the holding portion 1A is changed to press the side button 11, the elastic body 2 may be peeled off because it is formed by double molding or insert molding. There is no fear of shifting. In particular, the elastic body 2 in the vicinity of the edge of the opening window 1B of the shaft tube 1 is a part that is easily peeled off. However, since the elastic body 2 is firmly fixed to the concave groove 1C of the shaft tube 1, there is a possibility that the elastic body 2 is peeled off even in this part. Absent.
[0012]
【The invention's effect】
The present invention described above, particularly in peeling easily elastic portion close to the open window, since it is firmly fixed enters the elastic member into the groove of the barrel by a double molding or insert molding, circle elastic body Even if a stress in the circumferential direction is applied, there is an effect that there is no fear of peeling or shifting.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view showing a shaft cylinder of a writing instrument of the present invention.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
FIG. 3 is an enlarged cross-sectional view showing another embodiment of the shaft tube of the writing instrument of the present invention.
FIG. 4 is an enlarged cross-sectional view showing still another embodiment of the shaft tube of the writing instrument of the present invention.
FIG. 5 is a cross-sectional view showing an embodiment in which the shaft cylinder of the writing instrument of the present invention is used in a side knock type mechanical pencil.
6 is an enlarged sectional view taken along line AA of FIG.
7 is an enlarged sectional view taken along line BB of FIG.
FIG. 8 is a plan view of FIG. 5;
FIG. 9 is a plan view of a principal part showing a state before the rear shaft is connected to the shaft cylinder in the embodiment of FIG. 5;
10 is a plan view showing an eraser holder in the embodiment of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Shaft cylinder 1A Holding part 1B of axial cylinder 1 Opening window 1C of axial cylinder 1 Groove 2 of axial cylinder 1 Elastic body 101 Shaft cylinder 101A Holding part 101B of axial cylinder 101 Opening window 101C of axial cylinder 101 Concave of axial cylinder 101 Groove 102 Elastic body 201 Shaft cylinder 201A Grasping part 201B of shaft cylinder 201 Opening window 201C of shaft cylinder 201 Concave groove 202 of shaft cylinder 201 Elastic body

Claims (1)

In the shaft tube of a writing instrument in which an elastic body is formed by double molding or insert molding on the outer periphery of the grip portion of the shaft tube, the grip portion of the shaft tube is formed to be slightly recessed in diameter, and an opening window is formed in the grip portion. A shaft cylinder of a writing instrument, wherein a concave groove is formed on an outer periphery of the shaft cylinder adjacent to the opening window, and an elastic body formed on a grip portion of the shaft cylinder is also formed in the concave groove.

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