JPH0544157Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) This invention relates to a knock-type mechanical pencil, and more specifically, to a thin mechanical pencil whose main body is flat and thin, making it convenient to carry.

(Prior Art) Knock-type mechanical pencils are widely used in various shapes and structures, and in recent years, thin-type mechanical pencils with a flat rectangular shape have been on sale.

5 and 6 show a conventional example. FIG. 5 is an explanatory overall perspective view with the surface plate removed, and FIG. 6 is a perspective view of the core storage body.

1 is a shaft body, 2 is a holding plate, 3 is a core storage body, 4 is a connecting member, 5 is a split chuck, and 6 is a spring.

The shaft body 1 is a plate-like body with one end formed in an arcuate shape 1a, and the upper and lower surfaces are concave with projections 1b provided on the periphery, and a substantially rectangular through hole 1c is provided inside. Further, a base 1d for protruding the core is press-fitted into the arcuate shape 1a, and an insertion hole 1e for the core storage body 3 is bored at the other end.
e communicates with the through hole 1c.

The holding plate 2 has a spring locking projection 2a protruding from its inner surface facing the through hole 1c, and is fixed to a concave surface on one side of the shaft body 1. Therefore, this presser plate 2 forms a groove 1g into which the core storage body 3 is inserted, together with the through hole 1c.

Further, as shown in FIG. 6, the lead storage body 3 has a lead storage groove 3a, and is composed of a lead storage part 3b and a push button 3c that are fitted into the groove 1g. A recess 3d for fixing the holder 3 is formed. The connecting member 4 is formed to have a U-shaped cross section so as to fit into the core storage portion 3b, and has one end crimped and fixed in the recess 3d, the other end connected to the chuck member 5, and a spring engaging member at the side end. A stop protrusion 3e is provided in a protruding manner.
Therefore, the core storage body 3, the connecting member 4, and the chuck member 5 reciprocate as one, and are normally urged toward the rear end by the spring 6. The chuck member 5 is a bifurcated chuck having a tightening ring 3g, and the tightening ring 3g is disposed within the stepped portions 1h and 1k.

Further, the concave surfaces of the upper and lower surfaces are sealed with lid-like bodies such as aluminum plates.

In the above configuration, when the push button 3c of the lead storage body 3 is pressed in the state shown in FIG.
Centering is performed by moving toward the distal end of the shaft body 1 while holding it. That is, the tightening ring 3g is at the stepped portion 1h.
When it hits and its movement is blocked, only the chuck member 5 moves further, so that the core 8 is released and held by the cap 1d. Next, when the pressure on the core storage body 3 is released, the chuck member 5 returns to the rear end of the shaft body 1 together with the core storage body 3 and the connecting member 4 due to the biasing force of the spring 6, and the tightening ring 3g is stepped. Part 1k
The movement of the core is prevented, and the chuck is tightened by the tightening ring 3g, as shown in FIG. 6, to hold the core.

In this way, the reciprocating movement of the lead storage body 3 causes the lead to be fed out as a knocking action.

(Problems to be Solved by the Invention) Although the thin knob-type mechanical pencil having the above structure is convenient to carry, it has the following problems.

That is, since the structure is complicated, the number of parts to be assembled is large, which makes assembly not only time-consuming, but also difficult to achieve assembly accuracy. Furthermore, there is a limit to how thin the shaft body 1 can be made due to the large number of assembled parts.

(Purpose of the invention) This invention was made in view of the current situation.By simplifying the overall configuration, parts costs and assembly costs can be reduced, and the lead feeding operation can be performed smoothly and reliably. The purpose of the present invention is to provide a thin, click-type mechanical pencil.

(Means for Solving the Problems) Therefore, the thin mechanical pencil according to this invention has the following configuration.

That is, the centering mechanism 15 is inserted into the shaft body 10 having a rectangular through hole 11 so that both ends protrude,
A tip plug 50 and a tail plug 60 are fitted to both ends of a protruding centering mechanism 15, respectively, and the centering mechanism 15 has a notch 3 for storing a spring on the side surface.
2, a core storage body 30 with a core guide groove 31 bored on the back side and a chuck part 40 attached to one end, a chuck tightening ring insertion hole 23 at one end, and a spring locking at the side end. It consists of a base portion 20 with a protruding piece 25 erected thereon, and a coil spring 27 that biases the core storage body 30 in the direction of the shaft head, and the core storage body 30 is slidably inserted into the shaft body 10. It is characterized by being

(Function) The shaft body 10 is simply assembled with the centering mechanism 15.
The sharpening pencil is assembled in a removable manner by inserting it into the holder and fitting the tip plug 50 and tail plug 60 to both ends.

Since the coil spring 27 locks one end with the spring locking protrusion 25 and urges the core storage body 30 in the axial direction, the core storage body 30 resists this coil spring 27.
When pressed, the chuck portion 40 fixed to the lead storage body 30 moves at the same time to feed out the lead lead, and by repeating this operation, the lead lead protrudes from the tip plug 50.

(Example) Hereinafter, this invention will be described in detail based on an illustrative example.

Fig. 1 is a partially sectional plan view of the knock-type mechanical pencil according to this invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, Fig. 3 is an exploded perspective view for explaining parts, and Fig. 4. FIG. 2 is a cross-sectional perspective view for explaining the shaft body, the tip plug, and the tail plug.

In the figure, 10 is a shaft body, 15 is a centering mechanism, 2
0 is a base part, 30 is a core storage body, 40 is a chuck part, 50 is a tip plug, and 60 is a tail plug.

The shaft body 10 is a cylindrical body having a thin rectangular cross-sectional shape and having a through hole 11 inside in the axial direction, and the cross-sectional shape of the through hole 11 is approximately convex in the embodiment. .

The centering mechanism 15 includes a base portion 20, a coil spring 27, a core storage body 30, and a chuck portion 40.

The base portion 20 has side walls 22 erected on both sides of a bottom portion 21, and has a concave cross section. bottom 21
A chuck tightening ring insertion hole 23 for inserting a chuck tightening ring and regulating the movement of the tightening ring is formed at one end, and a spring insertion hole 24 is formed along the side wall 22 at the other end. is drilled, and spring insertion hole 2
A spring locking protrusion 25 is provided protruding from the inner end of 4. Although the spring insertion hole 24 is formed to a size sufficient to accommodate the coil spring 27, it may be omitted depending on the size or shape of the coil spring 27 to be attached.

The base portion 20 is inserted into the through hole 11 of the shaft body 10 with the core storage body 30 to which the chuck portion 40 is attached slidably embedded therein. Through hole 1
When the base portion 20 is inserted into the shaft body 1, both ends of the base portion 20 are formed in such a length that they protrude from both ends of the shaft body 10, and a tip plug 50 and a tail plug 60 are fitted into these protruding portions.

The core storage body 30 has a core guide groove 3 along the axis on the back side.
1. A spring storage notch 32 is formed on the side surface, and a chuck mounting groove 33 for fixing the chuck portion 40 is provided at one end. The core guide groove 31 is formed to communicate with the core guide groove 31. This core storage body 30 stores the coil spring 27 and the base portion 2
0 so as to be slidable in the axial direction, and biased in the direction of the axial head by a coil spring 27. At this time, the end surface of the axial head is formed on the same plane as the end surface of the base part 20.

Furthermore, the chuck portion 40 attached to the lead storage body 30 has a two-piece chuck, and consists of a base portion 41 that fits into the chuck attachment groove 33 of the lead storage body 30 and a chuck 42, and the side surface of the chuck 42 is tapered. A rectangular tightening ring 43 is attached. The tightening ring 43 is inserted into the tightening ring insertion hole 23 of the base member 20 so as to be freely slidable in the axial direction.

The tip plug 50 has a tapered tip and a cavity 51 that opens at the rear end, and this cavity 51 is connected to the shaft 10.
The base portion 20 has almost the same shape as the through hole 11 of
At the same time, the chuck portion 40 is inserted so that it can move forward and backward. A cap 52 is press-fitted and fixed at the tip, and a rubber stopper 53 for holding a lead core is provided coaxially with the cap 52.

As is clear from FIG. 4, the tail plug 60 is a cap body and is connected to the base part 2 in which the core storage body 30 is embedded.
It is fitted onto the shaft head of 0. A gap 61 is provided between the shaft body 10 and the tail plug 60 for moving the lead storage body 30 back and forth and performing centering.

Next, a method of assembling the click-type mechanical pencil according to the above structure and a click operation will be explained.

First, the chuck part 40 is attached to the lead storage body 30, and is slidably embedded in the base part 20 with the lead guide groove 31 facing downward. At this time, the chuck portion 40
The tightening ring 43 is inserted into the tightening ring insertion hole 23, and one end of the coil spring 27 is inserted into the spring storage notch 32 and the spring insertion hole 24 while being locked with the spring locking protrusion 25. Centering mechanism 1 assembled in this way
5 is inserted into the through hole 11 of the shaft body 10, and both ends are made to protrude. Next, the tip plug 50 and the tail plug 60 may be fitted onto the base portion 20 of the centering mechanism 15 protruding from the lead storage body 30. To insert the lead core, remove the tail plug and insert it into the lead storage groove 31.

Since this invention has the above structure, the inserted lead core S passes through the lead guide groove 31 and its tip reaches the chuck portion 40. In this state, when the lead storage body 30 is slid in the base part 20 against the coil spring 27 and is pressed in the distal direction, the chuck part 40 is inserted into the lead core S.
The clamping ring 43 of the chuck part 40 hits the tip of the clamping ring insertion hole 23 and its movement is prevented. Further, when the lead storage body 30 is moved, the chuck 42 comes out of the tightening ring 43 and releases the lead core from being held. When the pressure on the lead storage body 30 is released, the chuck portion 40 returns to the axial direction together with the lead storage body 30 due to the urging force of the coil spring 27, and the tightening ring 43 hits the rear end of the tightening ring insertion hole 23. The movement of the lead core S is stopped by the contact, and the tightening ring 43 tightens the chuck 42 to hold the lead core S as shown in FIG. In this way, the lead core S is fed out by repeating the reciprocating movement of the lead storage body 30.

In the above embodiment, the spring insertion hole 24 and the spring housing notch 32 were formed only on one side, but they may be formed on both sides.

(Effects of the invention) Since this invention is configured as described above, it is possible to simplify the shape of parts and reduce the number of parts. Furthermore, the product is easy to assemble, and the overall cost of the product can be reduced.

Furthermore, the lead core is fed out by the movement of the lead storage body, and together with the small number of parts, the lead feeding operation can be performed smoothly and reliably.

[Brief explanation of the drawing]

Figure 1 is a partially sectional plan view, Figure 2 is the 1st
A sectional view taken along the line A-A in the figure, FIG. 3 is an explanatory exploded perspective view showing the centering mechanism, and FIG. 4 is a shaft body,
FIG. 5 is an explanatory perspective view showing the structure of a conventional sharp pencil with the cap on one side removed, and FIG. 6 is a perspective view of the lead storage body. . 10 is a shaft body, 11 is a through hole, 15 is a centering mechanism,
20 is a base part, 21 is a bottom part, 22 is a side wall, 23
is a tightening ring insertion hole, 25 is a spring locking protrusion, 27 is a coil spring, 30 is a core storage body, 31 is a core storage groove,
32 is a spring storage notch, 33 is a chuck mounting groove,
40 is a chuck portion, 41 is a chuck base, 42 is a chuck, 43 is a tightening ring, 50 is a tip plug, 52 is a base, and 60 is a tail plug.

Claims (1)

[Claims for Utility Model Registration] A centering mechanism 15 is inserted into the shaft body 10 having a rectangular through hole 11 so that both ends protrude, and a tip plug 50 and a tail are inserted at both ends of the centering mechanism 15 that protrudes. Stopper 60
The centering mechanism 15 has a spring storage notch 3 on the side surface.
2, a core storage body 30 with a core guide groove 31 bored on the back side and a chuck part 40 attached to one end, a chuck tightening ring insertion hole 23 at one end, and a spring locking at the side end. It consists of a base portion 20 with a protruding piece 25 erected thereon, and a coil spring 27 that biases the core storage body 30 in the direction of the shaft head, and the core storage body 30 is slidably inserted into the shaft body 10. A thin mechanical pencil that is characterized by: