JPH0636888U - Mechanical pencil slider - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a lead guide slide type slider of a mechanical pencil that is not clogged with a folding lead, lead scrap, or the like. [Structure] An outer cylinder portion 11c is integrally and concentrically connected to the outer periphery of a rear end of a slider member 11b, and a plurality of slits 11g are provided in the outer cylinder portion 11c in an axial direction so that the outer cylinder portion 11c is provided with a predetermined friction resistance. The tip 2 is brought into sliding contact with the inner peripheral surface. Further, the concave and convex portions 11e and 11d are provided on the inner circumference of the slider member 11b to hold the core with a frictional resistance smaller than the frictional resistance.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a slider of a lead guide slide type sharp pencil for feeding a lead by a lead feeding operation by a knock.

[0002]

[Prior art]

 Normally, a mechanical pencil has a lead guide fixed to the tip of the tip, so the length of the lead protruding from the tip of the lead guide is limited to an almost constant value in terms of the fragility of the lead. Therefore, when writing for a long time, it is necessary to frequently knock the button etc. provided at the rear end of the core pipe. However, in this core feeding operation, the writing operation had to be interrupted by changing the grip, and there was a problem that the writing efficiency decreased.

In order to solve this problem, when a lead is worn, a sliding mechanical pencil or a lead in which the lead is slid according to the wear of the lead or a lead is pushed to a paper surface to obtain a desired amount. A mechanical pencil has been proposed that allows core feeding without changing the grip. For example, as proposed by the present applicant and disclosed in Japanese Utility Model Publication No. 3-47907, the centering slider is concentrically composed of two large and small cylindrical bodies having different diameters, and the large-diameter cylindrical body is sharp. Known is a centering slider that securely engages the inner surface of the tip of a pencil with a sufficiently large frictional resistance, and a small-diameter cylindrical body ensures that the core is held with a constant frictional resistance. Has been. With such a configuration, the number of parts and cost can be reduced, and durability and lubricity for centering can be improved.

[0004]

[Problems to be solved by the device]

 However, according to the centering slider configured as described above, the large-diameter cylindrical body and the small-diameter cylindrical body are concentrically integrated, and an annular gap is formed on the rear end surface of the slider. Therefore, when the lead is inserted into the slider, the lead may enter the gap and be broken. In addition, dust may be accumulated in the gap to prevent the slider from operating reliably.

The present invention has been made to solve the above-mentioned problems, and the purpose thereof is to reduce the breakage of the lead, to enable long-time writing, and to reliably deliver the lead. To provide a centering slider.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, in the invention according to claim 1, there is provided a slider having a through hole through which a core is inserted, the slider being inserted into a tip tool of an outer cylinder and movable in an axial direction within a predetermined range. A mechanical pencil slider that is concentrically fixed to the slider and has a core guide through which the core is slidably inserted, the slider being concentrically connected to a rear end outer periphery of a slider member, An outer cylinder portion having a plurality of slits in the axial direction and in sliding contact with the inner peripheral surface of the tip member with a predetermined frictional resistance is provided, and the outer peripheral portion of the outer cylinder portion is provided inside the through hole of the slider member. It is characterized in that a concavo-convex portion is provided between the core and the core to provide a frictional resistance smaller than that between the surface and the inner peripheral surface of the tip.

The invention according to claim 2 is characterized in that the concavo-convex portion formed on the inner circumference of the through hole of the slider member that constitutes the slider is formed in a spiral shape.

[0008]

[Action]

 According to this invention, the slider can surely be slidably engaged with the inner peripheral surface of the tip with a sufficiently large frictional resistance via the outer cylindrical portion provided on the outer periphery of the slider member. In addition, the core can be reliably held with a constant frictional resistance through the uneven portion provided on the inner circumference of the slider member. At this time, since the rear end face of the slider member and the outer cylindrical portion are integrally connected, no core, remnant, core dust, dust, etc. enter between them.

[0009]

【Example】

 An embodiment of a mechanical pencil slider of the present invention will be described below with reference to the drawings.

1 to 5 show the configuration of an embodiment of the present invention. 1 and 5, reference numeral 1 denotes an outer cylinder that can be held by a hand, and a tip 2 is integrally provided on the outer cylinder 1. A core pipe 3 is coaxially inserted into the outer cylinder 1, and a lead chuck 4 is connected to the tip of the core pipe 3. A receiving member (not shown) is detachably fitted to the rear end of the core pipe 3, and an eraser (not shown) is housed in the receiving portion of the receiving member. The leading end of the lead chuck 4 penetrates through the center of the chuck tightening ring 7, and the rear end of the chuck tightening ring 7 faces the front flange portion 8a of the cushion sleeve 8 which is axially movable in the outer cylinder 1. is doing. This cushion sleeve 8 is formed of a deformable elastic member such as polyacetal or the like and has a cylindrical shape as a whole, and a stopper portion protruding outward from the outer diameter of the body portion 8b of the rear end portion. 8 c is provided.

Further, a notch 8d is provided in the body 8b and a notch 8e that is long in the axial direction is provided at the rear end so that the stopper 8c generates an appropriate flexible elastic force with respect to the body 8b. ing. The shape of the stopper portion 8c is such that when the cushion sleeve 8 is assembled into the outer cylinder 1 together with the lead delivery mechanism, the stopper hole 8c is securely and smoothly engaged with the locking hole 1a formed in the outer cylinder 1 by a one-touch pushing operation. In addition, it has a slip-out prevention shape that engages so as to prevent backlash.

Therefore, the body portion 8b elastically displaces with respect to the stopper portion 8c supported in the locking hole 1a within the axial gap G of the notch 8d, and the body portion 8b is normally urged forward. Has been done. Further, between the front end of the core pipe 3 and the flange portion 8a of the cushion sleeve 8, an elastic body 9 for clamping the chuck for biasing the core pipe 3 to the rear side is interposed.

The tip 2 of the tip 2 is conical and thin at the tip, and the inner peripheral diameter of the tip has a locking surface 10 that is an inclined stepped portion that makes the inner diameter different. A slider 11 having a stopper surface 11a, which is slidable in the axial direction but whose forward displacement is restricted by the locking surface 10, is housed in the inner circumference of the tip portion.

As shown in FIGS. 2, 3, 4 and 5, the slider 11 is composed of a substantially cylindrical slider member 11b and an outer cylinder portion 11c, and the rear ends of the slider members 11 are coaxial. It is formed of a synthetic resin integrally-molded product integrally connected by. ABS resin, polyacetal, or the like is used as the synthetic resin. The center of the slider member 11b is formed so that the core is inserted, and a rib 11bb of a predetermined length is projectedly provided on the tip end side of the slider member 11b, and the core guide 12 for passing the core is press-fitted. It is fitted. Here, the rib 11bb is formed shorter than the total length of the slider member 11b. As a result, the slider member 11b and the core guide 12 are fitted with each other very smoothly and reliably.

Spiral uneven portions 11e and 11d are formed on the inner circumference of the slider member 11b so as to give a predetermined frictional resistance to the axial movement of the inserted core. . Further, a taper surface 11f inclined toward the center is formed on the rear end surface of the slider member 11b.

The rear end of the outer cylinder portion 11c is concentrically connected to the rear end of the slider member 11b. The outer cylinder portion 11c is provided with three slits 11g in the front end in the axial direction in this embodiment. Is formed so that the slider portion 11b is also formed with three slits 11h with its rear end opened in the axial direction, which allows the slider member 11b and the outer cylinder portion 11c to be radially repelled. Giving power.

Further, protrusions 11i are provided on the outer periphery of the outer cylinder portion 11c at intervals. The frictional resistance generated when the outer peripheral surface of the outer tubular portion 11c abuts on the inner peripheral surface of the tip tool 2 is greater than the frictional resistance between the inner peripheral surface of the uneven portions 11e and 11d of the slide member 11b and the core. It's getting really big.

Next, the operation will be described. Now, when no external forward force is applied to the rear portion of the core pipe 3, the cushion sleeve 8 is held at the front end of its movable region, while the lead chuck 4 biased in the backward direction is chucked. Since it retracts with respect to the tightening ring 7, the tip of the lead chuck 4 is tightening a core (not shown). In this state of FIG. 1, when the core pipe 3 is knocked from the eraser side, the lead chuck 4 also moves forward together with the chuck tightening ring 7, and the chuck tightening ring 7 causes the step 2a of the tip 2 to move. When it comes into contact with the lead chuck 4, only the lead chuck 4 advances, leaving the chuck tightening ring 7 to release the tightening of the lead.

When the knocking operation is released, the lead pipe 3 retracts together with the lead chuck 4, the chuck tightening ring 7 contacts the front edge of the cushion sleeve 8, and the leading end of the lead chuck 4 is tightened at this position. , The core is held, and the retraction of the core pipe 3 is stopped. By repeating this operation, the lead is sequentially fed, and the length of the lead fed by one lead feeding operation is almost equal to the distance from the front end of the chuck tightening ring 7 to the step portion 2a.

In the process of advancing the lead by such lead feeding operation, since the friction resistance between the lead and the uneven portions 11e and 11d is smaller than the friction resistance between the protrusion 11i and the inner peripheral surface of the tip tool 2, the lead is guided by the lead guide. 12 moves forward and you can write like a normal mechanical pencil.

Further, at the moment when the lead chuck 4 is fitted into the chuck tightening ring 7 when the rear end knock is released, there is no protrusion of the slider 11 because the protrusion 11i exists on the slider 11 when the lead is slightly backed. . That is, there is no crimping phenomenon in which the slider 11 moves forward and backward when the rear end is knocked.

On the other hand, when the tip of the lead is worn or broken during writing, the remaining lead is pressed against the paper surface or the like while the outer cylinder 1 is continuously gripped. Therefore, a force in the retreating direction acts on the lead chuck 4 and the lead pipe 3 that hold the lead, and these members, together with the chuck tightening ring 7 and the cushion sleeve 8, act on the bending of the stopper portion 8c. It retreats against the original resilience. The range of movement in the backward direction is set to, for example, about 0.5 to 1.0 mm.

By the way, since the stopper portion 8c is engaged with and supported by the notch 1a of the outer cylinder 1, the retracted region of each of these members has the maximum dimension G. Further, in the retracting process of the lead, after the leading end of the lead is retracted to the tip position of the lead guide 12, a pressing force also acts on the lead guide 12 from the paper surface, and the lead guide 12 is also retracted together with the slider 11. Then, when the lead has moved to the rear end of its moving range, the positions of the lead and the lead guide 12 coincide with each other.

Then, when the pressing of the outer cylinder 1 toward the paper surface is released, the body 8b of the cushion sleeve 8 moves forward to the front end of the movable range due to the restoring repulsive force due to the bending of the stopper 8c, As a result, the chuck tightening ring 7 advances together with the lead chuck 4 and the lead held by the lead chuck 4 and returns to the original position.

However, the core guide 12 does not move forward due to the large frictional resistance between the protrusion 11i and the inner peripheral wall of the tip tool 2, and therefore the tip of the core has a length corresponding to the above-described retreat amount of the core guide 12. , Will project from the tip of the lead guide 12. Then, the same operation can be repeated until the core guide 12 reaches the rear end of its moving range.

When it is necessary to further project the lead after the lead guide 12 reaches the rear end of its moving range, the lead pipe 3 is knocked to perform a normal lead feeding operation. By this operation, the lead chuck 4 contacts the rear end of the slider 11 and advances it to the front end of the moving range in the process of releasing the lead from the lead and further advancing. At this time, the lead moves forward with the slider 11 of the lead by the same amount, and thus the lead keeps its tip end aligned with the tip of the lead guide 12.

Next, when the knocking operation is released, the lead chuck 4 retracts with the core and the core guide 12 left in that position, and stops at the position where it engages with the chuck tightening ring 7. If the knocking operation is performed again in this state, the lead can be advanced by a predetermined length by the above-described operation.

As described above, when the lead guide 12 is in a position where it can be retracted, the mechanical pencil of the present invention does not rely on a knocking operation but simply presses the tip of the lead against the paper surface or the like to move the lead. It can be projected for a predetermined length and this can be achieved with a simple structure and assembly work by using a slider as a single synthetic resin molded product instead of using a cylinder and friction members such as rubber as in the past. it can.

Further, the slider 11 can be obtained in large quantity and at low cost, and can be made short, which is useful for shortening the entire length of the mechanical pencil. Thus, while the lead is consumed by the movable area of the lead guide 12, the lead feeding by the knocking operation is not necessary, and therefore the writing can be continued without changing the grip. Further, when an excessive pressure acts on the lead during writing, the lead is elastically retracted by the elastic action of the stopper portion 8c, so that the lead is effectively prevented from being broken.

Further, since the rear end face of each of the slider member 11b and the outer cylinder portion 11c which form the slider 11 are integrally connected, the core may be broken between them and broken or dust may be generated between them. It is possible to prevent the operation of the slider 11 from being hindered due to the inclusion of the above.

Of course, the number of slits 11h and 11g formed in the slider member 11b and the outer cylinder portion 11c is not limited to the three illustrated.

[0032]

As described above, according to the slider of the mechanical pencil of the present invention, since the slider member and the outer cylinder portion which constitute the slider are integrally supported, the core is inserted between them. It is possible to prevent the slider from being broken or having dust or the like entering the slider and hindering the operation of the slider. In particular, if the mechanical pencil is accidentally dropped and the core is broken by the impact, the core will not get caught in the slider and the next core will not come out.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the structure of a main part of an embodiment of a centering slider of a mechanical pencil of the present invention.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a plan view of the slider without the core guide of FIG.

FIG. 4 is a rear view of FIG.

5 is a front view without the lead guide of FIG. 2. FIG.

[Explanation of symbols]

 1 Outer Cylinder 2 Tip Tool 11 Slider 11b Slider Member 11c Outer Cylinder Part 11d, 11e Concavo-convex Part 11g, 11h Slit 12 Core Guide

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[Procedure amendment]

[Submission date] July 8, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (2)

[Scope of utility model registration request] 1. A slider, which has a through hole through which a lead is inserted, is inserted into a tip of an outer cylinder and is movable in an axial direction within a predetermined range, and the slider is concentrically fixed to the slider, In a mechanical pencil having a lead guide slidably inserted therein, the slider being concentrically connected to the outer periphery of the rear end of the slider member and having a plurality of slits in the axial direction. Is provided with an outer cylindrical portion that makes sliding contact with the inner peripheral surface of the slider with a predetermined frictional resistance, and is smaller than the frictional resistance between the outer cylindrical portion and the inner peripheral surface of the tip on the inner periphery of the through hole of the slider member. A mechanical pencil slider comprising an uneven portion for imparting frictional resistance between the lead and the core. 2. The slider of a mechanical pencil according to claim 1, wherein the uneven portion formed on the inner circumference of the through hole of the slider member constituting the slider is formed in a spiral shape.