JPH0140712Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a lead holder for a sharp pencil.
More specifically, the present invention relates to a lead holder for a sharp pencil that allows easy insertion of the lead.

The lead holder, which is placed in front of the chuck of a sharp pencil, can be used to achieve a certain length of lead delivery by stopping the lead in the forward position when the chuck is used to pay out the lead, and to hold the lead by holding the lead when the chuck returns to its original position. In order to prevent them from being brought back,
It is essential for mechanical pencils.

A conventionally known core holder 101 is made of an elastic material such as rubber, as shown in FIG. It has a lead holding hole 102, and has an inclined lead guide surface 103 at the rear of the lead holding hole 102 for guiding the lead into the lead holding hole 102,
The stepped portion 104 formed on the outer surface is attached to the inner step 106 of the shaft cylinder 105 by press-fitting, gluing, etc. so that it is in contact with the inner step 106 of the shaft cylinder 105.

However, in the case of such a lead holder 101, when the lead is inserted while maintaining the center position, the lead is inserted into the lead holding hole 102 without any problem, but due to some factors. For example, if the chuck itself is tilted due to an impact or the like and the lead deviates from the center position and is moved forward at an angle, the lead will be moved forward through the lead holding hole 10.
2, and as a result, it becomes impossible to feed out a new lead such as a second lead. This is because the lead is not inserted directly into the lead holding hole 102, which has a smaller diameter than the lead being used.
This is because it only deforms. In addition, a new problem arises in that the core holder 101 comes off from the shaft tube 105 due to this pressing force.

This idea was created in view of the problems mentioned above.
By devising the shape of the lead holder, it is an object of the present invention to provide a lead holder for a sharp pencil that can hold the lead as reliably as in the past and also facilitates insertion of the lead.

The present invention will be explained in detail below with reference to FIGS. 2 and 3.

Reference numeral 1 is the barrel of the sharp pencil;
2 is a core protection tube fixed to the tip of the barrel 1 by press fitting or adhesive, but in addition to what is shown in the figure, the tip of the barrel 1 is made thinner and the core protection tube 2 is integrally formed with the barrel 1. can also be adopted. 3 is a core holder made of an elastic material such as rubber, and the core holder 3 has a stepped portion 4 formed on its outer surface.
It is attached by press-fitting, gluing, etc. so as to be in contact with the inner stage 5 of the shaft cylinder 1. This attachment method may also be done by press-fitting another member into the shaft cylinder 1 from behind the core holder 3, other than as shown in the drawings. Reference numeral 6 denotes a lead holding hole having a diameter _S1 slightly smaller than the lead diameter to be used, and having an appropriate length for imparting elasticity to the lead and holding it therein, and a slanted lead guide auxiliary surface at the rear of the lead holding hole 6. A core guide hole 8 having an appropriate length and having approximately the same diameter S ₂ as the core diameter to be used is provided through the core 7 . Furthermore, an inclined core guide surface 9 is provided at the rear of the core guide hole 8 .

Next, the action will be explained.

When the lead advances from the rear of the lead holder 3, the lead is first guided by the lead guide surface 9 and inserted into the lead guide hole 8. Here, as in the past, there is a possibility that the lead deviates from the center position and moves forward, but since the diameter S ₂ of the lead guide hole 8 is approximately the same as the diameter of the lead being used, the lead can be reliably moved. It is inserted into the core guide hole 8.
When the lead advances further, the lead is inserted into the lead holding hole 6 via the lead guiding auxiliary surface 7.

As described above, in the present invention, the lead holder has a lead holding hole with a diameter smaller than the core diameter to be used, an inclined lead guide auxiliary surface, a lead guide hole with approximately the same diameter as the used lead diameter, and an inclined lead guide. Since the surface is continuous with the surface, the core to be inserted is first reliably regulated in its center position by the core guide hole, and then held by being given elasticity by the lead holding hole, making it easy to insert the core. is significantly better than the conventional one. Therefore, problems such as poor feeding of a new lead such as a second lead or loss of the lead holder can be solved.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part showing a conventional example, FIG. 2 is a vertical cross-sectional view of a main part showing the present invention, and FIG. 3 is an enlarged vertical cross-sectional view of a core holder. 3... Lead holder, 6... Lead holding hole, 7... Core guide auxiliary surface, 8... Core guide hole, 9... Core guide surface.

Claims (1)

[Scope of utility model registration request] A lead holder for a sharp pencil, which is continuously provided with a lead holding hole having a smaller diameter than the lead diameter, an inclined lead guide auxiliary surface, a lead guide hole having approximately the same diameter as the lead diameter, and an inclined lead guide surface.