JP2000198293A - Automatic feeding type mechanical pencil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate breakage of a lead and to incorporate a lead projected from a slider in the slider. SOLUTION: A slider 4 is provided axially slidably at a tip of a mouth piece 2. A chuck 13 and a chuck ring 8 combined to allow advancing of a lead 5 but to inhibit retracting of the lead 5 are provided in the mouth piece 2. A feeding spring 19 is disposed between the slider 4 and the chuck 13. The ring 8 is provided axially movably in the mouth piece and axially forward movably by a writing pressure spring 24. A chuck stopper 23 is disposed at an interval 22 to a rear end 14 of the chuck 13. The chuck 13 is stopped by the stopper 23 after being retracted at a predetermined amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic dispensing sharp pencil capable of automatically supplying a wick with writing.

[0002]

2. Description of the Related Art There is known an automatic dispensing-type sharp pencil capable of automatically supplying a wick with writing.
The basic structure of this type of sharp pencil is a slider which is provided at the tip of the base so as to be movable in the axial direction and frictionally holds the lead, a spring for urging the slider forward, and a forward movement of the lead. A chuck device is provided for releasably gripping the wick so as to allow movement but prevent retraction. And
At the time of writing, the leading end of the slider is made to come into contact with the paper surface and is retracted. When the leading end of the slider is released from the paper surface, the slider is advanced by the action of a spring and the lead is automatically extended.

[0003] In the automatic feeding type sharp pencil described above,
Since the retraction of the lead is prevented by the chuck device fixed in the barrel, the lead may be broken at the chuck portion when excessive writing pressure is applied. Also,
If the lead is too far outside the tip of the slider for some reason, the lead cannot be stored and may damage the body or break the lead when carrying.

[0004]

The problem to be solved by the present invention is as follows.
In the automatic dispensing type sharp pencil as described above, the automatic dispensing device is designed so that the lead is not damaged when excessive writing pressure is applied, and can be easily stored when the lead protrudes from the tip of the slider. The object is to provide a formula sharp pencil.

[0005]

According to the present invention, there is provided a base, a slider movably provided in an axial direction at a tip of the base, and a slider for frictionally holding a core, and a slider provided in the base in an axial direction. A chuck ring movably provided with a tapered surface on an inner surface, and a chuck ring inserted into the chuck ring to release gripping of the lead when the lead moves axially forward and push the lead backward. A chuck that clamps the core by being clamped by, a delivery spring that urges the slider rearward while urging the slider axially forward, and a writing pressure spring that urges the chuck ring axially forward. An object of the present invention is attained by providing an automatic feeding type pencil having a chuck stopper provided so that the chuck is in contact with the rear end of the chuck with a buffer interval.

[0006]

FIG. 1 shows an embodiment of the present invention.
In the figure, a base (2) is provided at the front end of the barrel (1),
A connecting cylinder (3) for attaching to the shaft cylinder (1) is formed at the rear part of the base (2). A slider (4) is provided at the tip of the base (2) so as to be movable in the axial direction.
Inside the slider (4), there is a holding portion for frictionally holding the core (5). In the embodiment shown in FIG. 1, an elastic piece (6) made of an elastic material is attached separately. There is, but Figure 2
As shown in (1), the slider (4) may be formed of a synthetic resin material, and a resilient holding piece (7) may be formed therein to frictionally hold the core. The base (2) is connected to the barrel by screwing, fitting, or any other appropriate method. The connecting tube may be omitted by directly attaching the base to the shaft tube.

A chuck ring (8) is provided inside the base (2) so as to be movable in the axial direction. The chuck ring (8) has an outer peripheral surface (9) slidably in contact with the inner surface of the connecting cylinder (3), and a taper surface (10) is formed on the inner surface, the front surface of which expands in the axial direction and the rear surface narrows. Have been. The tip (11) of the chuck ring (8) faces the rear end (12) of the slider (4). When the slider (4) is stored in a base as described later, the slider (4) Contact the rear end (12). When the connecting cylinder is omitted, the chuck ring may slide on the inner surface of the shaft cylinder.

A chuck (13) is inserted into the chuck ring (8), and preferably a rear end (1) of the chuck (13) is inserted.
4) protrudes rearward of the chuck ring, but may be configured so as not to protrude from the rear end of the chuck ring. The chuck (13) releases the grip of the core when the core (5) moves forward in the axial direction, and is tightened by the chuck ring (8) to grip the core when the core is pushed backward. It is configured. In the figure, the chuck (13) is
In the embodiment shown in the figure, a plurality of cylindrical bodies are formed in the axial direction, and two half-shaped chuck elements (13a) and (13b) are formed, and the chuck elements (13a) and (13b) are formed. Complementarily, the ball is inserted into the recess (15) formed on the outer surface of the chuck element.
The seat (16) is seated, and the ball (16) is inserted into the chuck ring (8) so as to be supported on the tapered surface (10) of the chuck ring (8). It is also possible to use a chuck of a type in which a slit is provided at the tip of the tubular body and an opening / closing action is provided at the slit portion to hold the core releasably (not shown).

When a chuck is constituted by the above-mentioned chuck elements, as shown in FIG. 4, a chuck element complementarily combined is inserted from the front of a chuck ring (8), and after the chuck elements (13a) and (13b). When the end (14) is projected rearward of the chuck ring (8), the outward projection (17) formed at the rear end is configured to abut the rear end (18) of the chuck ring (8). Since the chuck and the chuck ring are not separated in the assembled state, the assembly is easy. In addition,
The size of the projection (17) can be adjusted by pushing the combined chuck element strongly from the front to the rear of the chuck ring (8) from the rear end (18) of the chuck ring (8).
7) may project backward. Such a configuration can be easily implemented by making the chuck element and the chuck ring from a synthetic resin material.

An extension spring (19) is provided between the slider (4) and the chuck (13) to urge the slider (4) forward in the axial direction and to urge the chuck (13) backward.
The extension spring is set to a load smaller than the normal writing pressure. The extension spring (19)
Thus, the slider (4) moves forward until the step (21) comes into contact with the slider shoulder (20) provided inside the mouthpiece (2). The chuck (13) is provided at the rear end (1
4) and moves rearward in the axial direction until the rear end (14) comes into contact with a chuck stopper (23) provided with a buffering interval (22) for preventing the core from breaking.

The chuck ring (8) is urged axially forward by a writing pressure spring (24) so that the tip (11) comes into contact with a chuck ring shoulder (25) provided inside the base. Move forward to position. In a normal writing state, the load of the writing pressure spring (24) is set to a load that can withstand normal writing pressure so as to stop at this fixed position, and the extension spring (1) is used.
9) Larger than the load.

The chuck stopper (23) is fixed to the rear end of the connecting cylinder (3), the large-diameter portion (26) is fitted to the connecting cylinder (3), and the front of the large-diameter portion (26). A stopper surface (28) is formed at the tip of the small-diameter portion (27) provided at the bottom. The writing pressure spring (24) is provided between a shoulder (29) formed between the small diameter portion (27) and the large diameter portion (26) and a rear end (18) of the chuck ring (8). The small diameter portion (27) is formed so that the rear end (18) of the chuck ring does not contact. Therefore, the chuck (13) and the chuck ring (8) move rearward in the axial direction together, but the chuck (13) moves at a position where it hits the stopper surface (28) of the chuck stopper (23). Stopping, the chuck ring (8) can move further back. When the base is directly attached to the barrel without the connecting barrel, a stepped portion may be provided in the barrel to fix the chuck stopper in the barrel (not shown).

The chuck stopper (23) is connected to the connecting cylinder (3).
In order to fix the connecting cylinder (3), screwing, press-fitting, or other appropriate fixing means can be used. In the drawings, as shown in FIGS. ) To form an engagement groove (31) that opens rearward, and a chuck stopper (23)
An engaging claw (33) having a locking edge (32) on the outer periphery of the large diameter portion (26)
The chuck stopper (23) is inserted into the rear of the connecting cylinder (3), the engaging claw (33) is inserted into the engaging groove (31), and the engaging edge (32) is engaged with the engaging step (30). ). As shown in FIG. 8, an engagement window (34) is formed in the connecting cylinder (3), and an engagement projection (35) is provided on the outer periphery of the large-diameter portion (26) of the chuck stopper (23). The engaging projection (35) is connected to the engaging window (34).
May be engaged.

An eraser is often attached to the rear end of the barrel (1). The eraser may be directly fitted to the rear end of the barrel, but preferably, as shown in FIG.
6) is attached to the rear end of the barrel (1), and an eraser (37) is fitted to the eraser holder (36). The mounting of the eraser holder (36) is performed by inserting the hollow shaft (39) of the eraser holder (36) into a fitting portion (38) formed at the rear of the shaft cylinder (1) as shown in FIG. A slit (40) is formed at the tip of the shaft portion (39) so that the tip portion can bend in the radial direction, and a locking edge (41) formed on the outer periphery of the tip is provided inside the barrel (1). Shoulder (4
It is locked by 2). Also, eraser holder
The fitting part (38) of the barrel and the shaft part (39) of the eraser holder are made polygonal so that the (36) does not rotate easily, or a protrusion such as a rib is projected on the outer periphery of the shaft part of the eraser holder. Alternatively, the protrusion may be pressed against the fitting portion of the barrel to prevent rotation (not shown).

Thus, as shown in FIG.
Can be written in a state protruding from the base (2). The slider (4) retreats into the base with the writing, but if the tip of the slider is separated from the paper surface (43), the slider (4) moves forward by the extension spring (19) while holding the core, and Can be automatically paid out. If excessive writing pressure acts on the core, the chuck (13) and the chuck ring (8) are retracted together against the writing pressure spring (24) so that the core does not break at the chuck portion. I can do it. When the excessive writing pressure is removed, the slider, the chuck ring and the like are returned to the forward position by the spring, and writing can be continued.

If, for some reason, the lead is too far from the tip of the slider as shown in FIG. 10, the following operation may be performed. First, in the state shown in FIG. 10, the core (5) is
3) When a large force is applied in the axial direction of the lead by applying the force to the lead, the slider (4), the chuck (13), and the chuck ring (8) are retracted together with the lead (5), as described above. During the process, the rear end (14) of the chuck (13) comes into contact with the stopper surface (28) of the chuck stopper (23) and stops (FIG. 11).

The holding force of the core by the chuck (13) is such that the rear end (14) of the chuck hits the chuck stopper (23) and the rearward movement of the chuck is hindered. Only the force caused by the load of the pen pressure spring (24) for urging the slider in the slider direction acts. Therefore, if a force greater than this load is applied to the core,
The holding power of the chuck is no longer tolerable, the lead slides out, and the lead is stored inside the slider (4) (FIG. 12).

When a stronger force is applied to the core from the state shown in FIG. 12, the slider (4) retreats, and the rear end (12) of the slider (4) hits the tip (11) of the chuck ring (8). As a result, the chuck ring (8) is retracted, and the holding force of the writing pressure spring (24) is also lost, so that the slider (4) can be easily stored in the base (2) (FIG. 13). Then, when the tip of the slider is separated from the paper surface, the chuck ring (8) and the slider (4) are moved by the writing pressure spring (24).
In addition, the core is held by the delivery spring (19) and returns to the state shown in FIG. 1 so that writing can be performed.

[0019]

The present invention is constructed as described above, and includes a slider movable in the axial direction, a chuck and a chuck ring combined so as to prevent retraction of the core but allow forward movement, and the slider and the slider. Since the drawing spring is provided between the chucks, the slider is retracted with writing as in the case of a normal automatic drawing-type sharp pencil, the writing is stopped, and the slider is moved away from the paper and moved forward. Can be automatically paid out. The chuck ring is provided so as to be movable in the axial direction, and the chuck ring is urged axially forward by a writing pressure spring. Therefore, when excessive writing pressure greater than the writing pressure required for the core is applied. The chuck and the chuck ring move together in the axially rearward direction, thereby preventing breakage of the core.

Further, since the chuck stopper is provided so that the chuck comes in contact with the rear end of the chuck with a buffering interval, the core may protrude from the tip of the slider for some reason. In such a case, if the lead is pushed axially rearward with a force greater than the load of the pen pressure spring, the chuck and chuck ring together retreat axially rearward, and then only the chuck is prevented from retreating by the chuck stopper. As a result, the holding force of the lead is lost, the lead can be retracted into the slider, and the lead and the slider can be easily stored in the base. The slider can be made to protrude from the tip of the base in a state in which is matched, and writing can be performed.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing one embodiment of the present invention.

FIG. 2 is a partial sectional view showing another embodiment of the present invention.

FIG. 3 is a partial sectional view showing an embodiment in which a shaft cylinder is combined with the embodiment shown in FIG. 2;

FIG. 4 is a partial cross-sectional view showing a combined state of a chuck and a chuck ring.

FIG. 5 is a partial front view showing one embodiment of a rear portion of the connecting cylinder.

FIG. 6 is a front view showing one embodiment of a chuck stopper.

FIG. 7 is a partial front view of a state where the connecting cylinder and the chuck stopper are connected.

FIG. 8 is a partial front view showing another embodiment of the connection state between the chuck stopper and the connection cylinder.

FIG. 9 is a partial cross-sectional view showing a connecting portion between the shaft cylinder and the eraser holder.

FIG. 10 is a partial cross-sectional view in a state where a core protrudes from a slider.

11 is a partial cross-sectional view of a state where the chuck ring and the chuck are retracted from the state of FIG.

FIG. 12 is a partial cross-sectional view of a state where the core is stored in the slider from the state of FIG. 11;

13 is a partial cross-sectional view showing a state where the slider is housed in the base from the state of FIG. 12;

[Explanation of symbols]

 2 Base 3 Connecting tube 4 Slider 8 Chuck ring 13 Chuck 19 Extension spring 23 Chuck stopper 24 Writing pressure spring 28 Stopper surface 36 Eraser holder

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[Procedure amendment]

[Submission date] April 23, 1999 (1999.4.2
3)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 3

[Correction method] Change

[Correction contents]

Claims (4)

[Claims] 1. A base, a slider provided at the tip of the base so as to be movable in the axial direction, and frictionally holding the core, and a taper provided inside the base so as to be movable in the axial direction, and a taper on the inner surface. A chuck ring having a surface, and a chuck inserted into the chuck ring to release gripping of the core when the core moves forward in the axial direction, and to be clamped by the chuck ring to grip the core when the core is pushed backward. A delivery spring that urges the slider rearward while urging the slider axially forward, a writing pressure spring that urges the chuck ring axially forward, and a rear end of the chuck. An automatic dispensing sharp pencil having a chuck stopper provided so that the chuck comes in contact with a buffer space. 2. A rear end of the slider is provided such that when the chuck and the chuck ring move rearward in the axial direction, the rear end of the chuck contacts the chuck stopper and then contacts the front end of the chuck ring. Claim 1
2. The automatic dispensing-type sharp pencil according to item 1. 3. The post-chuck is formed by complementarily combining a plurality of chuck elements, and a ball is seated on an outer surface of the chuck element, and the ball is provided on the taper surface of a chuck ring. 2. The automatic dispensing sharp pencil according to claim 1, wherein a rear end of said chuck element projects rearward from a rear end of said chuck ring and is formed with a projection which abuts on a rear end of said chuck ring. 4. The base has a connecting cylinder, the chuck ring slides in the connecting cylinder, the chuck stopper is fixed to the connecting cylinder, and the writing pressure spring is connected to a rear end of the chuck ring. 2. The automatic feeding type shear according to claim 1, which is provided between shoulders formed on said chuck stopper.
Puppencil.