JPH0636953Y2 - Mechanical pencil chuck base piece - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a check of a pencil pencil.

It is known to form a tubular chuck by combining the chuck parts that are divided into two parts.
Injection molding that can take many pieces to mold each one of the above-mentioned chuck pieces individually, casting molding, etc. are adopted, but after molding, a chuck that exhibits a predetermined performance by arbitrarily combining a plurality of chuck parts is provided. Whether or not it can be obtained, various inspections, such as core pullout force measurement, check return amount measurement, pressure resistance measurement, core breakage during pressure resistance, core drop, writing durability, etc. must be performed in principle for each combination. I won't. Such an inspection must be performed periodically for stable performance and maintenance of performance, but the number of combinations of check pieces is very large, which is a time-consuming and labor-intensive operation.

In order to improve such a drawback, the present invention forms a set of chuck pieces in a state where their rear ends are connected, and folds them in two at the connecting portion after molding, and at that time, a portion which is not separated into a part of the notch. It is related to the check base piece of the shear pencil that prevents the set of check pieces from becoming disassembled before and after assembly.After the molding, the combination of the check pieces is determined, so the check pieces can be separated. Compared with this, the number of times is very small, it is economically obtained, and even after the assembly, the chuck pieces can be prevented from being displaced from each other, and the failure can be reduced.

A description will be given below with examples.

In the figure, the case where the present invention is applied to a chuck of an automatic pay-out type sharp pencil is shown. The shaft cylinder (1) and the mouthpiece (2) of the shear pencil are fitted and attached to the connecting tube (3) formed at the rear portion of the mouthpiece, but they can be attached by screwing or any other suitable method. A slider (5) is fitted in a hole (4) at the tip of the base (2) so as to be movable in the axial direction, and a core (6) is elastically held by a frictional action at the rear of the slider (5). The elastic piece (7) is provided so that the tip of the slider is a core guide pipe (8) made of a synthetic resin material having a small frictional action. The tip of the pipe (8) is formed into a tapered surface, and the slider (5) can be moved forward until the flange (9) formed in the middle portion comes into contact with the stepped portion (10) of the base (2).

At the rear part of the slider (5), a chuck (12) is provided, which is formed by combining two chuck part pieces (11) and (11) in a tubular shape to grip a core. The check is composed of a check base piece (13) made of a synthetic resin material. That is, a chuck base piece (13) having an approximately semicircular arc-shaped groove (14) extending in the longitudinal direction is formed on the inner surface, and the groove on both sides of the chuck base piece (13) is separated from the center of the chuck base piece (13). Towards one direction, the core guide part (15) and the core grip part (16) respectively
The spring seat (17) is provided at the outer end of the outer surface, and the ball receiving part (18) is formed at a position corresponding to the core gripping part (16), and the check part (11), (11) is formed. ) The rear end is connected. The outer periphery of the central portion of the chuck base piece (13) is foldable so that the cross section of the remaining portion is cut in a state where both side edges of the groove are connected when bent at the central portion.
A groove-shaped notch (19) is formed. When the notch portion (19) is notched, the chuck base piece (13) becomes the concave groove (14).
A connecting portion (20) is formed at both ends of the core and a core insertion hole (21) opening rearward is formed (FIG. 4), and the core gripping parts (16), (16) and the core guide part (15) are formed. , (15) face each other. The synthetic resin material is preferably filled with a short fiber filler (22) so as to reinforce the connecting portion. The filler is preferably a glass fiber having a length of about 0.3 to 0.5 mm, carbon fiber, a mustache-like crystal or other fibrous material, and the filling amount thereof is such that the surface of the chuck base piece does not become a rough surface, for example. If it is set to about 15 to 20%, when the above-mentioned chuck base piece is bent at the notch (19), the V-groove-like notch snaps from the groove bottom (Fig. 5) and the connecting part (20). ) Is enlarged, a part of the filler (22) is changed from one chuck part (11) to the other chuck part (11).
Will exist throughout the area (Fig. 6). The core gripping part (16) has an arc surface (23) at a portion contacting the core (6).
The contact state between the lead gripping portion and the lead is stable when the chuck is pulled in, and is stable.

The chuck (12) is assembled by folding in two as described above, and the inner surface of which is formed with the tapered surface (24) is the tightening tube (2).
5), and the tightening cylinder (25) is fixed to the connecting cylinder (3) of the base (2) by press fitting or the like. The check (1
A ball (26) is fitted between the ball receiving portion (18) and the tapered surface (24) of 2), and the chuck (7) is provided between the spring seat (17) and the slider (5). A spring (28) is provided so as to bias the (12) backward.

Then, the core (6) may be inserted from the rear end of the chuck (12). At this time, if the guide surface (27) is formed at the rear part of the chuck as shown in the figure, the core is inserted. Is easy.
Since the lead (6) is gripped by the chuck (12) and the like so as not to be pulled in, it is possible to withstand writing pressure and write. The slider (5) is pushed into the mouthpiece (2) along with the writing, but if the writing is stopped, the slider (5) protrudes from the tip of the mouthpiece (2) while holding the core by the spring (28) and continues. Can be written down. During use, the chuck part pieces (11) and (11) forming the above-mentioned chuck (12) are connected by the connecting parts (20) on both sides of the core insertion hole at the rear end, so that the ball receiving part and the core gripping part. It is possible to use it in a stable state without causing positional deviation between them.

In the above embodiment, the ball chuck used in the automatic pay-out type shear pencil has been described, but the present invention is also applicable to the collect chuck used in the knock-type shear pencil and the like.

The present invention is constructed as described above, and the chuck base piece (13) is made of the synthetic resin material, and the chuck base piece (13) is
(11) It has a rod shape in which the rear ends are connected to each other, and it is easy to handle because it does not hang, and when it is folded from the V-groove-shaped notch (19) formed on the outer periphery of the central portion, the chuck base piece is always Chuck pieces (11) and (11) are formed which are connected to both side edges of a substantially semi-circular concave groove that is divided into two parts centering on the folded portion and the core insertion that opens rearward when folded in a facing state The hole (21) appears, and the performance inspection of the combination of the chuck pieces may be performed on the pair of chuck pieces formed in this way, and the performance is stable and easy to maintain. Since the chuck parts of the set are connected to each other, the assembling work is easy and the occurrence of failure is small.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a sectional view, Fig. 2 is a side view of a chuck base piece with one side cross section, Fig. 3 is a perspective view of the chuck, and Fig. 4 is a rear portion of the chuck. Perspective view, fifth
FIG. 7 is an enlarged side view of the broken portion, FIG. 6 is an enlarged sectional view of FIG. 5, and FIG. 7 is an enlarged sectional view of the lead gripping portion. 1 ... Shaft cylinder, 2 ... Clasp, 11 ... Check piece, 12 ...
Check, 13 …… Check base piece, 14 …… Concave groove, 19 …… Break, 20 …… Coupling, 21 …… Core insertion hole

Claims (2)

[Scope of utility model registration request] 1. A chuck base piece formed of a synthetic resin material and having a substantially semi-arcuate concave groove extending in the longitudinal direction on the inner surface thereof, wherein the chuck base piece has the concave grooves on both sides of the central boundary. Each of which is divided into a core guide portion and a core grip portion, and a V-groove shape in which a cross section of the remaining portion can be broken with connecting portions provided on both side edges of the concave groove on the outer periphery of the central portion. A chuck base piece of a mechanical pencil, which is characterized in that a broken portion is formed. 2. A mechanical chuck pencil base piece according to claim 1, wherein the synthetic resin material is filled with a short fiber filler so as to reinforce the central connecting portion.