JPH03197199A - Method for boring air hole in metal shaft body of writing utensil and air hole boring device - Google Patents

Abstract

PURPOSE:To reduce processing labor and to facilitate mass production by inserting a core in a small diameter part and setting the connection part of the small diameter part and a large diameter part to a positioning part and pressing a punching body from the outside of the small diameter part to bore an air hole. CONSTITUTION:A metal shaft body 10 has a large diameter part 11 and a small diameter part 12 and the large diameter part 11 is inserted in the hole 21 of a holder 20 to be held thereto. When downward force is applied to a jacket body 80, a guide member 40 does not move because it is in contact with the metal shaft body 10 but a cam 70 and the jacket body 80 is displaced downwardly against the elastic force of an elastic member 90. A punching body 50 itself is limited from downward displacement because it is inserted in the hole 43 of the guide member 40 but, since a rear end part 52 comes into contact with the taper surface of the cam 70 in a slidable manner, the punching body 50 is displaced toward the internally present metal shaft body 10. The punching body pierces the side wall of the small diameter part of the metal shaft body 10 by this displacement when the downward displacement quantity of the jacket body 80 is increased.

Description

[Detailed Description of the Invention] (Industrial Application Field) An air hole is bored in the small diameter part of the metal shaft of a writing instrument, which has a small diameter part from which a pen tip protrudes at the tip and a large diameter part that forms an ink chamber. The present invention relates to a method and an air hole punching tool.

(Prior art) The metal shaft of a writing instrument with a pen tip protruding from the tip is often used for various writing instruments such as retractable nib type, and usually has a small diameter part from which the pen tip protrudes and an ink chamber. Stainless steel,
It is manufactured by reducing the diameter of a portion of a pipe body made of appropriate metal such as brass by press working or the like.

Although it is often used as a refill, it still needs to have the basic function of a writing instrument.

It is said that it satisfies various mechanisms regardless of the type of writing instrument, such as a ballpoint pen, a small tube type writing instrument, a fiber pen, or a plastic pen. One of these is an air hole that communicates between the inside and the outside, and although there are some models that have this air hole in the tail plug, they are often formed by drilling a hole in the small diameter part with a drill or the like.

(Problems to be Solved by the Invention) Drilling with a drill requires a lot of processing time and is not suitable for mass production.

(Means for Solving the Problems) The present invention provides the following advantages: ``An air hole is formed in the small diameter part of a metal shaft body of a writing instrument having a small diameter part from which a pen tip projects from the tip and a large diameter part forming an ink chamber. In this method, a mandrel is inserted inside the small diameter part, and a connecting part between the small diameter part and the large diameter part is used as a positioning part, and the punched body is pressed from outside of the small diameter part. ``Method for punching air holes in a metal shaft of a writing instrument, which has a small diameter part from which a pen point projects, and a large diameter part that forms an ink chamber. A punching tool for drilling an air hole in the small diameter portion, the guide member having a wall portion that comes into contact with a connecting portion between the small diameter portion and the large diameter portion, and having a tapered surface, A cam that is slidably displaceable, a mandrel that is fixed to the guide member and inserted into the small diameter portion, and a rear end that is slidably abutted on the tapered surface of the cam. a punching body inserted into a hole formed in the guide member so as to be displaceable; the mandrel is inserted into the small diameter portion of the metal shaft until the guide member abuts the metal shaft; cams are relatively displaced, and the punched body comes into sliding contact with the tapered surface of the cam and is slidably displaced within the hole of the guide member;
This makes it possible to punch air holes into the metal shaft from its outer wall. ” is the gist.

(Example) An example is shown in attached Figure 1.

Reference numeral 10 is a metal shaft body, which has a large diameter part 11 and a small diameter part 1.
2, and the large diameter portion 11 is inserted into the hole 21 of the holder 20 and held.

A mandrel member 30 in the form of a small diameter pipe is inserted into the small diameter portion 12 of the metal shaft 10 from the distal end side. The tip 31 is slightly bulged to reduce play, but it is not forced into the small diameter portion 12. Also, there is a hole 32 at the tip 31 that penetrates the side wall. It is formed. Furthermore, the rear part (upper part of the drawing) of the mandrel member 30 is a male threaded part, and two female threaded members 33 and 34 are screwed into this male threaded part.

In this example, the pipe-shaped mandrel member 30 is used because it is convenient for applying oil through the through hole and for introducing air to remove dust. In addition, the core member 30. Female thread members 33, 34 constitute the mandrel in this example. That is, the female screw members 33 and 34 may originally be integrated with the mandrel member 30, but in the case shown in the figure, the protruding length of the mandrel member 30 can be varied by changing the tightening positions. In order to do this, it is a separate member.

A guide member 40 is inserted into which the core member 30 and the female screw members 33 and 34 are inserted, and the lower end of the female screw member 33 is held in place while a fixing screw 41 fixes them.

Further, in the lower part of the guide member 40 in the drawing, there is a wall portion 42 that comes into contact with the connecting portion between the large diameter portion 11 and the small diameter portion 12 of the metal shaft body 1o.
and a certain distance above this wall portion 42, the mandrel member 3
Two holes 43 are formed at positions corresponding to hole 32 of 0.

A punching body 50 is inserted into this hole 43, and the guide member 4o is supported by an elastic member 60 such as a coil spring.
is biased outwardly. As will be described later, the tip 51 (the end on the center side in the drawing) of the punched body 50 becomes the part where the air hole is bored, and has a slightly smaller diameter than the hole 32 of the mandrel member 30. Further, the rear end portion 52 is tapered.

It abuts on the rear end 52 of the punched body 50, and also on the guide member 40.
The cam 70 interpolates this.

The portion of the cam 70 that comes into contact with the rear end 52 of the punched body 50 has a tapered surface 71. Further, the cam 70 is connected to the mantle body 8.
0 with a fixing screw 81, and the guide member 40 is biased downward in the drawing by an elastic member 90 such as a coil spring stretched between the guide member 40 and the mantle 80. Furthermore, a cam 70 is provided in a notch 44 provided in the upper side wall of the guide member 40 in the figure.
A screw 72 forming an inward protrusion is inserted to prevent the guide member 40 and the cam 70 from rotating. Thereby, the guide member 4o and the cam 70 are in a state where they can be slidably displaced. This prevents the lid member 82 of the mantle 80 from disassembling. In addition, in the above description, some parts are shown as multiple members as appropriate, similar to the core member 30 and the female screw members 33, 34, etc. described above. In addition, there are some members that are not provided with reference numerals and are not explained, but they are some of the members that may be integrated as appropriate.

Now, if a force is applied to the mantle 80 in a downward direction in the drawing, the guide member 40 will not move because it is in contact with the metal shaft 10, but the cam 70 and the mantle 80 will react to the elastic force of the resilient member 9o. It resists and is displaced downward. Furthermore, since the punched body 50 itself is inserted into the hole 43 of the guide member 40, it is restricted from being displaced downward;
By slidingly contacting the tapered surface 71 of the metal shaft 10, the metal shaft body 10 is displaced inwardly. This displacement penetrates the side wall of the small diameter portion 12 of the metal shaft body 10 when the amount of downward displacement of the mantle body 80 is increased.

Thereafter, when the mantle body 80 is moved upward in the drawing, the punched body 50 is pulled out by the resilient member 60, and then the entire punched body 50 is displaced upward together with the guide member 40 and the like. After the mandrel member 30 is pulled out, the metal shaft body 10 has a small diameter portion 1.
2, an air hole is bored at a certain distance from the large diameter portion 11. In addition, in order to carry out the next processing, the mandrel member 30 is moved to the metal shaft 10 until the guide member 40 comes into contact with the metal shaft 10.
into the small diameter portion 12 of the cam 70, relatively displacing the cam 70,
The punched body 50 may be displaced.

Next, another example is shown in FIGS. 2 and 3.

The difference from the previous example is that the rear end 52 of the punched body 50 is prevented from coming off the tapered surface 71 of the cam 70. That is, in this example, the elastic member 60 is not used, and instead the punching body 50 is attached to the tapered surface 71 of the cam 70.
A concave portion 73 into which the rear end portion 52 is fitted is formed, and the punched body 50 is forced to be slidably displaced within the hole 43 of the guide member 40 in accordance with the vertical movement of the cam 70. . Thereby, the punched body 5o can be reliably displaced backward after the air holes are punched.

FIG. 4 shows an example of the shape of the final processed product of the metal shaft 10 obtained in this manner. The small diameter portion 12 is obtained by making the tip portion 13 into a smaller diameter portion, shaping the opening into which a pen tip member (not shown) is inserted, and other necessary shaping of the inner and outer wall surfaces. The air holes are designated by reference numeral 14. Products in which an ink relay core having a straight side wall protruding from the rear end of the nib member are inserted into an ink absorption body housed in a large diameter portion are well known.

In addition to the above, various other things can be done. For example, in the method of the present invention, the displacement of the cam in the vertical direction in the drawing and the displacement of the punched body in the lateral direction in the drawing can be made independent. Even if the metal shaft side is moved, there is relatively no change. Furthermore,
In the air hole punching tool of the present invention, the mandrel member 30 in the above-mentioned one is provided with the hole 32 at a position corresponding to the punched body 50; It is also possible to arrange a member to be inserted into the hole 32 and to secure a gap corresponding to the hole 32 between the insertion tip of the insertion member and the tip of the mandrel member 30.

(Effects of the Invention) According to the method of the present invention, unlike drilling using a drill, the processing is less labor intensive and mass production is easy. Furthermore, the positions of the air holes to be formed are also highly accurate. Further, when the air hole punching tool of the present invention is used, the air hole can be punched simply by applying force in one direction, and the occurrence of burrs can be sufficiently suppressed. There is little occurrence of burrs on the inner wall of the small diameter portion of the metal shaft, and ink leakage through these burrs can be sufficiently prevented.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of a main part showing an example of the present invention. Fig. 2 is a vertical cross-sectional view of the main part showing another example, Fig. 3 is a cross-sectional view taken along the line 1-1 in Fig. 2, and Fig. 4 is a partially cutaway main part showing an example of the manufactured metal shaft body. Longitudinal cross-sectional view. DESCRIPTION OF SYMBOLS 10... Metal shaft body, 11... Large diameter part, 12... Small diameter part, 13... Tip part, 14... Air hole, 20...
・Holder, 21... Hole, 30... Core metal member, 31
... tip, 32 ... hole, 33 ... female screw member, 3
4... Female screw member, 40... Guide member, 41...
Fixing screw, 42... Wall portion, 43... Hole, 44...
Notch portion, 50... Punching body, 51... Tip portion, 52.
...Rear end portion, 60... Elastic member, 70... Cam, 7
DESCRIPTION OF SYMBOLS 1... Tapered surface, 72... Screw, 73... Recessed part, 80... Mantle body, 81... Fixing screw, 82...
- Lid member, 90... Resilient member.

Claims (2)

[Claims] (1) A method of drilling an air hole in the small diameter part of a metal shaft of a writing instrument having a small diameter part from which a pen point protrudes at the tip and a large diameter part forming an ink chamber, the method comprising: forming an air hole in the small diameter part of the writing instrument; A metal shaft of a writing instrument, in which a mandrel is inserted into the shaft, and the connecting portion between the small diameter portion and the large diameter portion is used as a positioning portion, and a punching member is pressed from outside of the small diameter portion to make a hole. How to punch air holes into the body. (2) A punching tool for punching an air hole in the small diameter part of a metal shaft of a writing instrument, which has a small diameter part from which a pen point protrudes at the tip and a large diameter part forming an ink chamber, the small diameter part and the large diameter part forming an ink chamber. a guide member having a wall portion that abuts the connection portion with the large diameter portion;
a cam having a tapered surface and slidably displaceable with respect to the guide member; a mandrel fixed to the guide member and inserted into the small diameter portion; a punched body inserted into a hole formed in the guide member so as to be slidably displaced by slidingly contacting the metal shaft; is inserted into the small diameter portion of the metal shaft body, the cam is relatively displaced, and the punched body comes into sliding contact with the tapered surface of the cam and is slidably displaced within the hole of the guide member. , an air hole punching tool which is thereby capable of punching an air hole in a metal shaft from its outer wall.