JP2561058Y2 - Tactile stick-out mechanical pencil - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to an operation in which, when a lead is worn out during writing, the finger is lightly pulled backward with a fingertip to a touch finger provided at the tip of the shaft while maintaining a writing state. In addition, the present invention relates to an improvement of a stylus dispensing mechanical pencil which enables dispensing of a required amount of lead.

[0002]

2. Description of the Related Art As a conventional example, the applicant of the present invention has disclosed a stylus extending mechanical pencil in Japanese Utility Model Publication No. 64-1107. According to this, a joining cylinder 6 is press-fitted and fixed to the outer periphery of the front end of the chuck case 2 to the shaft cylinder 7, and a shaft joint 8 is screwed to the inner diameter of the front end of the joining cylinder 6.
A screw portion is formed in the outer diameter portion of the front end of the shaft coupling 8,
A base 10 to which the tip pipe 9 is fixed is screwed here. A central portion 14 of a feeding body 13 fitted around the holding chuck 12 is provided inside the inner diameter of the shaft coupling 8, and the feeding body 13 projects a piece portion 15 outward from the center portion, and has a tip end at the tip thereof. The short finger portion 16 is formed. One part 15 of the feed-out body 13 penetrates a slit 17 provided in the axial direction from the tip of the shaft joint 8 toward the rear, and exposes the touch finger part 16 to the outer periphery of the shaft joint 8. In the case where the lead is normally fed out separately from the feed-out of the contact finger, the lead guide 1 connected to the knocking operation part compresses the coil spring 20 interposed between the joint cylinder 6 and the chuck case 2 to connect the shaft joint. 8 is advanced until it abuts against the rear end, and then the lead fixing chuck 4 is opened and the lead is fed out. When the knock is released, the chuck case 2 retreats, but at that time, it is necessary to retreat with the core fixing chuck 4 being opened. Therefore, lead guide 1
Needs to be configured to frictionally engage the outer periphery of the chuck case 2 with a stronger force than the coil spring 5. As described above, the conventional example has a disadvantage that it is easily deformed due to the provision of the slot 17 in the screw portion of the shaft coupling 8. For this reason, poor sliding of the feeding member 13 and loosening of the base 10 are likely to occur. Therefore, those members are actually provided by metal work products, and the member costs are relatively high. In addition, the conventional example has a problem that the cost is further increased since the number of parts is large and the number of screw portions is large.

[0003]

Therefore, the present invention improves the structural disadvantages of the conventional example, makes it possible to make most of the main members resinous, and eliminates the members so that the cost can be greatly reduced and the cost can be reduced. It is intended to provide a finger extension type mechanical pencil.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, a stylus dispensing mechanical pencil of the present invention has a sufficient core holding force for writing due to a structure in which a core fixing chuck is tightened with a ball. However, it is a mechanical pencil that requires only a small amount of force to pull out the core from the chuck, and the barrel, base, feeding body, and touch finger are each formed as a synthetic resin molded product, and the center of the shaft side is slightly forward. A cap having a guide slit formed therein is fixed to the tip of the barrel by screwing or press-fitting, and a locking piece that fits into the guide slit and is slidable and elastically deformable in the inner diameter direction is provided inside the cap. Fitting the dispensing body having it, providing a holding chuck at the center of the dispensing body, and exposing a ring-shaped touch finger portion that engages with the locking piece and interlocks with the dispensing body to the outside of the base, Inside of the contact part , Characterized in that form in the pressed state in the front finger portions touch with intervening coil spring between the Sawayubi portion and the base.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The illustrated embodiment will be described. An eraser stopper 31 having an eraser 32 attached thereto is fixed to a rear end hole of a lead case 9 which appropriately protrudes from the rear end of the barrel 1, and a rear end of the lead case 9 is provided. A knock cover 33 is detachably fitted on the outer periphery. A slit 26 is formed in the rear end side surface of the barrel 1, and a step portion 28 having a tapered portion 27 is formed substantially in the center of the slit 26, and a base portion is formed on the side surface of the core case 9 at the same position. A clip 29 integrally provided at 30 is provided, the base 30 is fitted into the slit 26, the tapered portion 27 is elastically deformed, and the rear end of the base 30 abuts the step 28 of the slit, and the core case 9 is pivoted. It is retained behind the cylinder 1.

A lead guide 10 is formed integrally with the leading end of the lead case 9, and a recess 11 is provided on the outer periphery of the lead guide 10. A slot 7 is formed on the rear side surface of the chuck case 2 to be described later, and a projection 8
Is provided. The lead guide 10 is fitted into the rear end hole of the chuck case 2 so that the concave portion 11 and the convex portion 8 are locked. That is, when the concave portion and the convex portion come off, the core guide 10 and the chuck case 2 are frictionally engaged. There are various means for frictional engagement between the lead guide and the chuck case, but the configuration of this portion is not the gist of the present application, so that further description is omitted. Also, lead case 9
Is normally urged rearward by a coil spring 12 between itself and the shaft cylinder 1.

[0007] A fastening cylinder 6 is fixed to the tip of the chuck case 2. The inner diameter portion at the front end of the tightening cylinder 6 has a tapered shape, and a core fixing chuck 3 in which balls 4, 4 す る in contact with the tapered surface are fitted into the outer surface recess is provided. It is pressed rearward by a coil spring 5 interposed between a step formed at the rear end. The core fixing chuck 3 is made of a synthetic resin molded article having excellent elasticity and high abrasion resistance, and is configured in a state where a split cylindrical body is combined. When writing pressure acts on the lead, the balls 4 and 4 roll and the lead fixing chuck 3 is tightened by the wedge effect to hold the lead, but when the lead is pulled out forward, the spring force of the coil spring 5 is used. Is set to be weak so that it becomes possible with a small force of about several grams. Incidentally, the chuck case 2 is formed of a resin molded product, and the tightening cylinder 6 is formed of metal processing. Originally, the chuck case and the tightening cylinder are integrally formed, but the cost is high if the metal is used due to the complicated processing. In addition, durability is insufficient when made of resin. The reason why the tightening cylinder 6 is made of metal is that consideration is given to wear resistance due to rolling of the ball and rigidity of the tapered portion. If the durability is compromised, an integrated resin molded product may be used.

A screw portion is formed in the outer diameter portion of the front end of the barrel 1, and a resin base 13 to which a tip pipe 14 is fixed is screwed to the screw portion. The base 13 may be press-fitted into the outer diameter portion of the front end of the barrel 1 in some cases. Further, the tip pipe may be formed integrally with the base 13. Further, a guide slit 15 is formed in the center of the side surface of the base 13 slightly in front of the shaft, and a feeding body 16 is slidably fitted inside the base 13. The feeding body 16 is centered on the holding chuck 1.
8 is fixedly provided, and at a predetermined position corresponding to the guide slit 15, a locking piece 19 having a projection 20 that can be elastically deformed in the inner diameter direction is integrally formed on the rear end side outer periphery,
The locking piece 19 fits into the guide slit 15 so as to be slidable, and the protrusion 20 is appropriately projected outward from the guide slit 15. Further, the tip of the tightening cylinder 6 and the feeding body 1
A gap is provided between the base 6 and the opposing surface when the base 13 is at the forefront position of the base 13 by the amount of feeding by the knocking operation.

The touch finger portion 21 is made of a resin having a ring shape, and a concave groove 22 is formed on an outer peripheral portion at a substantially distal end.
Inside, a hole 23 is provided at a position corresponding to the protrusion 20 of the feeding body 16. The touch finger portion 21 is fitted to the outside of the base 13, and the protrusion 20 is elastically fitted into the hole portion 23 to be locked with each other, so that the touch finger portion 21 and the feed-out body 16 are integrally linked. An O-ring 24 is fitted in the concave groove 22. The O-ring 24 is effective as a non-slip when the touch finger is operated with a finger. Further, an interval for extending the touch finger is provided between the rear end of the touch finger portion 21 and the base 13.

Further, a coil spring 25 is interposed between the finger part 21 and the base 13 inside the finger part 21 to urge the finger part 21 in a pressed state forward. Since the spring force of this spring may be larger than the force for pulling out the lead from the lead fixing chuck 3, it can be set to about 10 to 20 grams.

[0011]

The dispensing body 16 can be slid rearward by pulling it lightly rearward with the external touch finger portion 21 and moving the locking piece 19 along the guide slit 15.
Next, when the finger is released, the holding chuck 18 holds the lead and returns forward, so that the lead can be extended. The extension amount is a value of an interval at which the rear end of the touch finger portion 21 contacts the step portion of the base 13 facing the same. When the core is normally extended, the rear end of the knock cover 33 may be knocked. The core guide 10 at the tip of the core case 9 connected to the knock cover 33 is interposed between the core guide 9 and the inner step of the barrel 1. While the compressed coil spring 12 is compressed, the tightening cylinder 6 integrated with the chuck case 2 is advanced (the core guide 10 and the chuck case 2 are interlocked because the concave portion 11 and the convex portion 8 are locked). The tip abuts against the step 16a of the facing unwinding body 16, and then
The leading end of the lead guide 10 comes into contact with the rear end of the lead fixing chuck 3, and the lead fixing chuck 3 is opened to feed the lead. (Because the forward movement of the chuck case 2 is prevented, the engagement between the concave portion 11 and the convex portion 8 is released and only the core guide 10 advances.) Then, when the rear end knock of the knock cover 33 is released, the convex portion 8 is 10, the chuck case 2 is retracted together with the core case 9 while the core fixing chuck 3 is open, and the chuck case 2 is
Is prevented from retreating at the front end, only the lead case 9, that is, the lead guide 10 retreats, and the concave portion 11 is locked to the convex portion 8 again.

[0012]

[Effects of the Invention] The present invention is as described above. Since there is no notched slit to the end of the conventional shaft coupling, structural defects such as poor sliding of the touch finger portion and loosening of the screw portion are eliminated. You.
Further, the shaft cylinder, the base, the feed-out body, and the touch finger portion are each formed as a synthetic resin molded product, and the members are simplified, so that a significant cost reduction can be achieved. In addition, although there is a problem of quality due to processing variations in conventional complicated metal processing and screwed portions, in the present application, since it can be formed by resin molding using a metal mold, there is no variation between members and the effect of stabilizing quality is also exhibited.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a stylus extending mechanical pencil which is an embodiment of the present invention.

FIG. 2 is a top view showing an external appearance of a mechanical stylus extended by a touch finger according to an embodiment of the present invention, showing a partially cross-sectional view of a clip portion.

FIG. 3 is a sectional perspective view of a base used in the present invention.

[Explanation of symbols]

 Reference Signs List 1 shaft cylinder 2 chuck case 3 core fixing chuck 4 ball 4 ス プ リ ン グ ball 5 coil spring 6 tightening cylinder 7 through slit 8 convex part 9 core case 10 core guide 11 recess 12 coil spring 13 base 14 tip pipe 15 guide slit 16 16a Step 17 Central part of unreeling body 18 Holding chuck 19 Locking piece 20 Projecting part 21 Touch finger 22 Depressed groove 23 Hole 24 O-ring 25 Coil spring 26 Slit 27 Tapered part 28 Step 29 Clip 30 Base 31 Eraser stopper Tools 32 Eraser 33 Knock cover

Claims (1)

(57) [Scope of request for utility model registration] 1. A structure in which a core fixing chuck is tightened with a ball has a sufficient core holding force for writing.
In a mechanical pencil that requires only a small amount of force to pull out the lead from the chuck, the barrel 1, the base 13,
The main members of the feed-out body 16 and the touch finger portion 21 are each formed as a synthetic resin molded product, and a base 13 having a guide slit 15 formed slightly in front of the center of the shaft side surface is screwed or press-fitted to the tip of the barrel 1. A dispensing body 16 having a locking piece 19 which is fixed and is slidably fitted in the guide slit 15 and elastically deformable in the inner diameter direction is fitted in the base 13,
A holding chuck 18 is provided at the center of the feeding body 16, and a ring-shaped touch finger portion 21 which is engaged with the locking piece 19 and integrally works with the feeding body 16 is provided so as to be exposed outside the base 13. A stylus extension type mechanical pencil, in which a coil spring 25 is interposed between the stylus 21 and the base 13 inside the stylus 21 so as to press the stylus 21 forward.