JP2554260B2 - Sharp pencil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a sharp feed that automatically performs core feed by writing off the slider from the paper surface, etc., and can lock the slider at the retracted position when not in use. Regarding pencils.

[Conventional technology]

Recently, when the writing pressure is applied, the lead is gripped, and when the writing pressure is released, the lead itself moves from the chuck to the writing tip due to the elastic force of the slider and the friction imparting part inserted in the slider. An automatic mechanical pencil has been proposed in which the gripping action of the chuck on the lead is released when the lead is released to the side, and a so-called known one-way type chuck device for feeding the lead is built-in and which is also capable of rear end knocking.

[Problems to be solved by the invention]

However, in both cases, the internal structure such as the lead feeding mechanism is very complicated, the efficiency of the assembling work is poor, the number of parts is large, and the lead is caught in the lead chuck during use, which often causes failure. There was a point.

Therefore, the applicant of the present invention has previously provided the mechanical pencil disclosed in JP-A-63-260493 as an original structure of the mechanical pencil.

According to this mechanical pencil, the internal structure is relatively simplified, and there are three lead feeding operations (automatic writing, tip knock,
It can be done with the rear end knock), and the slider can be locked and stored. In addition, in the lead feeding operation with the tip knock, the lead is fed not only when the lead is not protruding, but on the contrary, the lead is excessive by a predetermined amount or more. When it was protruding, the effect of just cushioning was obtained without delivering the core.

The present invention relates to the improvement of the above-mentioned prior application, and an object of the present invention is to provide a mechanical pencil that can surely knock the tip when the slide tip projects from the tip.

[Means for solving problems]

The mechanical pencil according to the present invention has a simplified internal structure, and the slider is unlocked and the slider is locked and stored by a body ring fitted to the tip of the sleeve.

[Action]

In the mechanical pencil according to the present invention, the slider is unlocked by the abutment of the sleeve ring at the tip of the sleeve, and a part of the slider is housed and locked.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of a mechanical pencil according to a first embodiment of the present invention, in which a tip 2 detachably attached to a tip of an outer cylinder 1 and an axially slidable inside of the tip 2. The accommodated slider 3, the sleeve 4 axially slidably arranged in the tip tool 2, the lead delivery mechanism 5 mounted in the sleeve 4, and the inside of the rear side of the sleeve 4 are described. It has a stopper 6 slidable in the axial direction and a joint 7 fitted and connected in the stopper 6.

The front tool 2 is, as shown in FIGS. 1 to 3 and 5,
It has a fitting portion 21 with the outer cylinder 1, and a rear side cylinder portion 22 that is connected to the rear end of the fitting portion 21. As shown in FIGS. 1 to 5, a pair of symmetrical sliding grooves 23 are provided in the rear tubular portion 22, and a slit 24 for surely elastically deforming the rear tubular portion 22 in the radial direction. Have and.

The pair of sliding grooves 23 are, as shown in FIGS. 1 to 5,
It has a crank shape and a symmetrical shape along the axial direction.
Sleeve protrusion sliding groove on which the sleeve protrusion 41 described later slides
23a and stopper protrusion 61 slide stopper protrusion slide groove 2
3b and a sleeve retreat regulation step portion 23c formed at the rear end of the sleeve projection sliding groove 23a. The sleeve retreat restricting step portion 23c has a function of restricting the retreat movement of the sleeve projection 41 that has retreated due to a tip knock or an excessive writing pressure buffering operation described later.

Here, a distance a is provided between the sleeve retreat regulation step portion 23c and the rear end of the stopper projection 41 in a state where no external force is applied (see FIG. 1).

Further, the stopper protrusion locking wall portion 23d formed at the rear end of the stopper protrusion sliding groove 23b engages the stopper protrusion 61,
As will be described later, each block 2 has a function of making the block 2, the sleeve 4, and the joint 7 into one unit block.

On the other hand, an annular slider receiving portion 8 is fitted on the inner wall of the tip of the tip tool 2 as shown in the first illustration.
An annular slider stopper 81, which engages the slider 3 in a disengageable manner, is provided on the inner side of the rear end so as to project inward.

As shown in FIGS. 1 and 6 to 8, the slider 3 includes a slider body 31, a slide chip 32 inserted into and fitted to the tip of the slider body 31, and a slider body 31.
Is installed inside the core and the core S has a predetermined frictional force (for example, 13 to 20).
g) and a friction imparting member 33 having a bilaterally symmetrical shape having no directionality. On the rear side of the slider body 31, a plurality of (four in this embodiment) engaging pieces 34 which are elastically deformable in the diametrical direction so as to be engageable with and disengageable from the slider stopper 81 are formed separately. Each of the 34 is formed with an engaging projection 35 that engages with and disengages from the slider stopper 81, an engaging recess 36 that engages with the tip engaging portion 96 of the body ring 9 when the lock is housed, and an inclined surface portion 36a. There is.

In addition, in FIG. 1, the slider 3 and the upper half portion of the protrusion bar 10 described later (shown in FIGS. 1 (A) (i) and 1 (B) (i)) are special external forces such as no writing. A vertical cross-sectional view when not added (hereinafter, referred to as normal time), on the other hand, a lower half portion (Fig. 1 (A) (ii), Fig. 1 (B) (i
(I) is a longitudinal sectional view at the time of locking, which will be described later.

A sleeve 4 is arranged in the tip tool 2 so as to be slidable in the axial direction.

As shown in FIGS. 1, 9, and 10, the sleeve 4 has a tubular shape, and a pair of sleeves that slide in the sleeve projection sliding groove 23a of the tip 2 on the outer circumference on the front side. A protrusion 41 is provided so as to protrude, and on the other hand, on the rear side, a friction slide groove 42 that allows the stopper protrusion 61 to slide while applying a predetermined friction force.
Are formed in a pair with the same shape.

Here, as shown in FIGS. 9 and 10, the friction sliding groove 42 has a guide groove 42a for guiding the stopper protrusion 61 and a sliding groove 42b communicating with the guide groove 42a. A friction step 43 is formed in the middle of the moving groove 42b. As will be described later, the friction step portion 43 applies a frictional force to the stopper protrusion 61, and the entire sleeve 4 together with the stopper 6 is moved by a predetermined amount.
It fulfills the function of advancing and delivering the core S.

As shown in FIG. 1, the sleeve 4 has a protruding bar 10 at its front end through a body ring 9, a core delivery mechanism 5 inside, and a joint 7 at its rear end. Stoppers 6 that engage with each other and are slidable in the axial direction are arranged.

The body ring 9 is fitted to the tip of the sleeve 4 and has a function of internally holding the protruding bar 10 movably, and a portion near the rear end of the slider 3 when the slider 3 is locked and is engaged. The rear step portion 91 has a function of engaging through the recess 36 and a function of preventing the ball 53 from falling off, which will be described later. Here, the tip side of this body ring 9 is
As shown in the twelfth illustration, in order to securely store the protrusion bar 10 inside and the rear end near bar of the slider 3,
At least one or more axially extending slits (four in this embodiment) 92 are formed. 93 is the protruding bar 10
Is an inner wall portion that movably accommodates within a predetermined range. 94
Is an inner wall step and regulates the backward movement of the protruding bar 10. Reference numeral 95 denotes a front end wall portion, which has a function of pressing and abutting the rear end of the slider 3 at the time of knocking the front end to release the lock and a function of releasing the lock storage of the slider 3, as described later. Further, 96 is the above-mentioned tip engaging portion.

A distance b is provided between the tip (tip wall portion) 95 of the body ring 9 and the rear end of the slider receiving portion 8. This distance b is a distance at which the core can be fed at the time of knocking at the trailing edge and at the edge of the leading edge and automatic writing can be continued.

The protruding bar 10 held by the body ring 9
As shown in FIGS. 1 and 13, a cylindrical portion 101 extending axially in the center thereof, a core conduction hole 102 formed in the cylindrical portion 101, and a first elastic body 11 described later. A locking portion 103 that locks the rear end, an outer peripheral wall portion 104 that movably accommodates the inner wall portion 93 of the body ring 9, and a rearward position of the outer peripheral wall portion 104,
It has a rear step portion 105 that comes into contact with the inner wall step portion 94 of the body ring 9 and restricts backward movement. 106 is a tip wall portion.

In the above-described normal state, as shown in FIG. 1, (a) a distance b is provided between the rear end of the slider 3 and the rear end of the slider receiving portion 8 and the front end wall portion 95 of the body ring 9. There is.
As will be described later, this distance b is the core feed amount of the trailing end knock and the leading end knock, and is a range in which so-called automatic writing is possible. (B) Engagement protrusion 35 of slider 3
And a distance c is provided as a retreat distance for the slider stopper 81 to engage.

Further, a first elastic body (for example, elastic force 10 g to 12 g) 11 is provided between the protruding bar 10 and the slider 3. The first elastic body 11 is provided inside the slider 3 and outwardly adjacent to the tubular portion 101 of the protruding bar 10 to urge the slider 3 forward, and at the same time, the protruding bar 1
0, the rear sleeve 4 and the like are urged rearward.

Incidentally, the tubular portion 101 of the protruding bar 10 extends long in the axial direction,
The core S is covered as much as possible to prevent the core from breaking and to prevent core scraps and cores from entering the lead chuck 51.
The rear end of the first elastic body 11 is locked.

Next, the lead delivery mechanism 5 arranged in the sleeve 4 will be described.

The lead delivery mechanism 5 is divided into two lead chucks 51 and a ball holding portion 52 at the head of the lead chuck 51.
An inner taper wall 54a which is fitted between the ball 53 held by the ball 4 and the tip of the sleeve 4 if necessary, and which fits and holds the ball 53 between the ball holding portion 52 and the ball 53. It has a metal cylinder 54, and a second elastic body 56 for tightening the chuck that is elastically fitted between the inner wall step 44 of the sleeve 4 and the locking step 55 of the lead chuck 51.

The lead chuck 51 is a metal molded product formed by forging or pressing, a sintered alloy, die casting or the like,
Alternatively, it is made of synthetic resin or the like formed by injection molding or compression molding.

The lead chuck 51 is provided with a lead insertion hole as shown in FIGS. 1 and 14 to 17 in this embodiment.
57 is divided into two parts along the axis of 57, each consisting of a pair of chuck members 51a, 51b formed in a hemispherical cross section,
The ball holding portion 52, a rear locking step portion 55, a rear taper cylindrical portion 58 extending rearward from the rear end of the locking step portion 55 and gradually decreasing in diameter on the rear end side, and the core of the shaft center portion. It has an insertion hole 57, an engaging concave portion 59, an engaging convex portion 510, and an opening / closing fulcrum convex portion 511.

Here, in the engaging concave and convex portions 59, 510, the engaging convex portion 510 of one chuck member 51a is in the engaging concave portion 59 of the other chuck member 51b, and the engaging convex portion 510 of the other chuck member 51b is one. Of the chuck members 51a are engaged with each other to prevent axial displacement of the chuck members 51a and 51b.

Further, the opening / closing fulcrum convex portions 511 of the chuck members 51a, 51b are brought into contact with each other to function as a fulcrum for leveraging the chuck members 51a, 51b in the opening / closing direction, and are sufficient for smooth lever movement. It has a spacer function of forming a gap K (see FIG. 1).

In addition, the engaging protrusion 51 in the radial direction of the core insertion hole 57.
By increasing the length of 0 by the length of the opening / closing fulcrum convex portion 511, these opening / closing fulcrum convex portions 511 can be omitted.
Still, a spacer function for forming the gap K can be obtained.

A small-diameter stepped core holding hole portion 512 is provided at the tip end side of the core insertion hole 57 in the inner wall of the head of the lead chuck 51.

The core holding hole portion 512 is a half-divided hole formed along the center line direction of the inner peripheral surface of the half-divided core insertion hole 57 in each of the chuck members 51a and 51b, and the cross-sectional shape thereof is, for example, FIG. 21 are formed as shown.

That is, the lead holding hole portion 512 is formed in a substantially U-shaped cross section in which the chuck side of the lead S is gradually widened.

A plurality of tooth portions 511 are integrally formed on both inner surfaces of the core holding hole portion 512 at predetermined intervals along the width direction thereof.

As shown in FIGS. 18 to 21, these tooth portions 511 are formed in a taper shape whose tip side is gradually sharpened, and each tip surface 511a is a narrow flat surface.

Further, each tooth groove bottom portion 513 of the tooth portion 511 is also formed in a planar shape.

Further, the tooth portion 511 is provided with a core support portion 514 that supports the outer periphery of the core S at four points in a combined state of the chuck members 51a and 51b.
Is formed.

As described above, the core support portion 514 formed of the tooth portion 511 can obtain a sufficient core insertion force and perform proper core holding,
Moreover, since the dust such as core dust escapes, the core dust does not collect on the whole, and even if the dust collects, it can be removed naturally by moving the lead such as sending out the lead. Be seen.

Therefore, even with frequent writing over a long period of time, an excellent effect that slippage does not occur during writing can be obtained.

22 to 24 show another embodiment of the chuck members 51a and 51b.

In the embodiment shown in FIG. 22, the tooth portion 511 is formed so as to project only in the vicinity of the core support portion 514, and the core attachment area is enlarged.

In the embodiment of FIG. 23, the core holding hole portion 51 in the previous embodiment is used.
The second tooth portion 511 is removed, and both sides of the open end portion of the lead holding hole portion 512 are used as lead support portions 514.

In the embodiment shown in FIG. 24, the core holding hole portion 512 shown in FIG. 22 is formed in a V-shaped cross section.

Therefore, even in the case of the lead holding hole portion 512 shown in FIGS. 22 to 24, substantially the same effect as the case shown in FIGS. 18 to 21 can be obtained.

The core holding hole portion 512 in each of the above embodiments may have any other cross-sectional shape as long as it can support the core S at four points as described above.

On the other hand, the ball 53 held by the head of the lead chuck 51 is fitted and held between the ball 53 held by the head of the lead chuck 51 and the inner tapered wall 54a of the metal cylinder 54 provided at the tip of the sleeve 4, as shown in FIG. There is.

The metal cylinder 54 ensures reliable and durable rolling contact, and moreover, the lead chuck 51 can be reliably held by the core and the durability is increased.

Here, the metal tube 54 is not always necessary, and in normal use, the inner surface tapered wall may be formed on the inner surface of the distal end of the sleeve 4 so as to be in rolling contact with the ball 53, and the metal tube 54 may be omitted.

In this embodiment, the one in which the lead chuck 51 is divided into two parts is used, but it may be divided into three or more parts, or conversely, it may be formed in a single piece.
Further, in order to prevent the lead chuck 51 from being displaced in the axial direction, it is also possible to form a concave-convex engaging portion or a notch for preventing the displacement at mutual contact portions. Also, the lead chuck 51
A part of the diameter of is very close to the inner diameter of the sleeve 4, and
The rear end of the second elastic body 56 is a locking step portion of the lead chuck 51.
The lead chuck is securely attached by the 55.
It is possible to reliably prevent the vertical and horizontal backlash and displacement of the 51. Further, the ball holding portion 52 of the lead chuck 51 is simply
It may be a hole for holding the ball 53, but may be housed and held so that the ball 53 does not fall off. The ball 53 is rotatable within the ball holding portion 52.

Also, the second elastic body 56 has a weaker elastic force than the first elastic body 11.

Then, the stopper 6 provided on the rear end side of the sleeve 4
As shown in the first illustration, a pair of stopper projections 61 are vertically provided so as to project, and as described above, are fixed to the distal end of the joint 7 so as to penetrate therethrough. The stopper protrusion 61 is abutted and locked by the stopper protrusion locking wall 23d of the tip 2 by the biasing force of the third elastic body 12 in the backward direction, and as will be described later, the tip 2 and the sleeve are respectively formed into blocks. 4 and joint 7 function as one unit block, sliding groove of sleeve 4 at the time of rear end knock
42a, a function of slidingly engaging the friction step portion 43 to advance the sleeve 4 by a predetermined amount, a stopper 6 by the subsequent advance,
Lead chuck by advancing joint 7 and core pipe 13 only
It presses and abuts on the rear end portion of 51 to fulfill the function of opening the lead chuck 51.

In the normal state described above, a distance d is provided between the tip of the stopper 6 and the contact portion of the lead chuck 51, as shown in the first illustration.

The joint 7 inserted into and engaged with the stopper 6 serves as a lead guide and detachably connects the core pipe 13, and has a core feed hole formed in an inner diameter capable of conducting only one core S. 71, and a chuck housing hole 72 for detachably inserting the chuck opening / closing mechanism 14 that is continuously formed at the rear end of the lead hole 71 and is fitted to the tip of the lead pipe 13 in this embodiment.
A large-diameter stepped fitting hole 74 connected to the rear end of the chuck housing hole 72 so that the front end side of the core pipe 13 is detachably fitted, and a projection provided on the inner wall of the fitting hole 74. And an engaging projection 75 for surely connecting the core pipe 13.

As described above, the chuck opening / closing mechanism 14 is attached to the tip of the core pipe 13.

The chuck type opening / closing mechanism 14 is described in detail in Japanese Patent Application Laid-Open No. 63-59600 already filed by the present applicant.

A third elastic body 12 is elastically attached to the tip 2 of the joint 7 via a receiving portion 15. The third elastic body 12 has a function of returning the sleeve 4, the lead delivery mechanism 5, and the ejecting bar 10 in the forward direction when knocking at the tip, a joint 7 when returning, and a function of returning the core pipe 13 in the backward direction. It functions as a buffer against excessive writing pressure, and has a relatively strong resilience (for example, 370g to 400g).

The receiving portion 15 that receives the tip end side of the third elastic body 12
Contacts the rear end of the tip 2 and the rear end of the sleeve 4 on the tip side thereof, and by such contact, one third elastic body
12 makes it possible to perform the above three functions.

When the receiving portion 15 is brought into contact with the rear end of the sleeve 4, the receiving portion 15 presses the rear end side of the sleeve 4 of the inner wall hole 15a as shown in FIG. Since the diameter of the sleeve 4 is reduced in the diameter direction, the sleeve 4 and the receiving portion are
15 is firmly coupled, and the receiving portion 15 does not come off from the sleeve 4 and the stopper 6 does not come out from the sleeve 4.

Here, the force relationship between the urging force A of the first elastic body 11, the frictional force B of the friction imparting member 33 to the core S, and the feeding force C of the lead chuck 51 of the core S will be summarized.

B> A. This is because when the tip knocking described later is performed, if this relationship is not satisfied, a core slip occurs between the friction imparting member 33 and the core S.

A> C. This is because it is necessary to pull the lead S forward from the lead chuck 51 by moving the slider 3 forward when performing tip knocking and so-called automatic writing described later.

Next, there is a relationship of d>a> c between the distances a, c and d described above.

Next, the assembly of the mechanical pencil according to the present invention will be described.

First, the core feeding mechanism 5 is incorporated into the sleeve 4. That is, the chuck members 51a and 51b are combined with each other, and the second elastic body 56 is loosely fitted to the outer periphery thereof. On the other hand, the metal cylinder 54 is previously press-fitted into the inner wall portion of the tip of the sleeve 4. Then, the chuck member 51a in which the second elastic body 56 is loosely fitted,
Insert 51b from behind sleeve 4. Next, the chuck members 51a, 51b are pressed from the rear to compress the second elastic body 56, and the balls 53 are held by the ball holding portions 5 of the chuck members 51a, 51b.
The ball 53 is reliably set in the ball holding portion 52 by releasing the pressure after being inserted into the inside. After that, the body ring 9 is pressed into the tip of the sleeve 4. At this time, the protruding bar 10 to which the first elastic body 11 is engaged is stored in the body ring 9 in advance.

Through this series of assembling operations, the sleeve 4, the lead delivery mechanism 5, the body ring 9, the protruding bar 10 and the first elastic body 11 are made into a block.

On the other hand, in the tip tool 2, the slider receiving portion 8 and the slider 3 are provided.
And are assembled and set in advance to block the front tool 2.

Further, the third elastic body 12 and the elastic body receiving portion 15 are set in the joint 7, and finally the stopper 6 is engaged to form a block. Here, the stopper 6 is biased by the biasing force of the third elastic body 12 via the joint 7 that is penetratingly engaged and the receiving portion 15.

Next, a description will be given of the work excluding the outer cylinder 1, that is, the work of unitizing the block-shaped tip 2, the sleeve 4, and the joint 7. This unitizing work is carried out by first blocking the sleeve 4 from the rear end of the block-shaped front tool 2.
Insert. By this insertion, the sleeve protrusion 41 of the sleeve 4 engages with the sleeve protrusion sliding groove 23a of the tip 2 as shown in the first illustration, and the pair of sliding grooves 2 of the tip 2
3 and the pair of friction slide grooves 42 of the sleeve 4 are located at fixed positions.

Next, the blocked joint 7 is inserted from the rear end of the tip 2 and the sleeve 4. This insertion is performed so that the stopper protrusion 61 of the stopper 6 at the tip of the joint 7 is engaged with the sliding groove 23 of the tip 2 and the friction sliding groove 42 of the sleeve 4.

Here, the stopper 6 is the third elastic body as described above.
Since it is biased by 12, the rear side wall portion 61a of the stopper protrusion 61 is pressed and locked by the stopper protrusion locking wall portion 23d of the sliding groove 23 of the tip 2 as shown in the first illustration. Become.
As a result, the block-shaped tip 2, the sleeve 4, and the joint 7 are unitized and can be handled as one unit block.

Finally, the unit block is inserted and fitted from the front end of the outer cylinder 1, and the core pipe 13 is inserted from the rear end of the outer cylinder 1 into the joint 7 to complete the assembly of the mechanical pencil.

 Next, the core feeding operation of the present invention will be described.

 This core feeding operation is performed in the following three ways.

(1) First, the first means is a normal means that is performed by knocking the rear end of the core pipe 3.

That is, in the state shown in FIG. 1, when the rear end of the core pipe 13 is knocked, the joint 7 advances while compressing the third elastic body 12. At this time, since the stopper 6 at the tip of the joint 7 is locked by the frictional force of the friction step portion 43 of the sliding groove 42b of the sleeve 4, together with the joint 7, the entire blocked sleeve 4, that is, , The sleeve 4, the lead delivery mechanism 5, the barrel ring 9 and the ejecting bar 10 advance, and these advance until the tip of the barrel ring 9 contacts the rear end of the slider receiving portion 8. That is, these are integrated and the body ring 9
It advances by the distance b between the tip of the slider and the slider receiving portion 8.
This distance b is the core feed amount. Then, the core pipe 13, the joint 7 and the stopper 6 are further pressed forward, the stopper projection 61 rides over the friction step portion 43 of the sleeve 4, and only the stopper 6, the joint 7 and the core pipe 13 advance. Then, the tip of the stopper 6 presses the rear end of the lead chuck 51 forward to release the holding of the core S, and by repeating the above operation,
Perform normal lead feeding.

(2) As a second means, the lead feeding operation can be automatically performed by interrupting the writing.

That is, writing is normally performed in a state where the core S projects from the slide tip 32 by a predetermined amount X as shown in FIG.
Then, as the writing is performed, the core S is gradually worn out,
26 As shown in the figure, it is flush with the tip of the slide tip 32. Even in this state, the slider 3 can retreat rearward against the urging force of the first elastic body 11, so that the slider 3 further contacts the tip wall portion 95 of the body ring 9 to the maximum extent, that is, FIG. The retreat distance b shown in FIG. 26 is possible.

By the way, it takes a very long time for the amount of wear of the lead S due to the writing to reach the receding distance b. By the way, the amount of abrasion of the core when writing one Kanji on high-quality paper with a normal adult writing pressure, thick HB, mechanical pencil with a core diameter of 0.5 mm.
It is only about 0.01 mm. Therefore, it is normally impossible to perform continuous writing until the slider 3 moves backward by the backward distance b, and it is considered that writing is always interrupted, such as writing break. So, for example, interrupt writing in the state shown in Figure 27,
It is assumed that the tip of the slide tip 32 is removed from the paper surface.
As a result, the slider 3 moves forward by the elastic force of the first elastic body 11, and the core S is also pulled in the forward direction together with the slider 3 by the predetermined frictional force from the friction applying member 33. On the other hand, since the chuck tightening force of the lead chuck 51 that is sticking to the core S is given by the second elastic body 56, which is weaker than the first elastic body 11, the above-mentioned core S is used.
The lead chuck 51 is compressed by the pulling force in the advancing direction to allow the advancing of the entire lead chuck 51. During this forward movement, the head of the lead chuck 51 causes the ball 53 to make rolling contact with the inner taper wall 54a of the metal cylinder 54, and as the forward movement progresses, the core chucking force of the lead chuck 51 weakens and the lead S is delivered. Be seen. By this series of operations, the state shown in FIG. 26 is restored again, the core feeding operation is automatically performed, writing becomes possible, and continuous writing up to the retracted distance b of the slider 3 can be performed.

(3) The third means is core feeding by knocking the tip of the slider 3 against the paper surface. There are the following two cases of this tip knock, and the actions thereof are different, so the cases will be described separately.

(A) The first tip knocking is performed in a state where the core S does not project from the tip of the slide tip 32 as shown in the 26th illustration.
The state of FIG. 25 (X = b) in which the length S of the distance b projects from 32 is obtained.

That is, due to the knock at the tip, the slider 3 is retracted by the reaction force of pressing from the paper surface, and the blocked sleeve (that is, the sleeve 4, the lead delivery mechanism 5, the body ring 9, the protruding bar 10) and the receiving portion 15 are also removed. , The third elastic body 12 and the frictional force generated between the stopper projection 61 and the friction step portion 43 of the sleeve 4 are retracted. This is because when the lead chuck 51 retracts with the core S attached, the entire blocked sleeve and the receiving portion 15 receive the external force in the retracting direction. Here, the amount of retreat of the slider 3 and the blocked sleeve and the receiving portion 15 is the same amount, and the distance a <d. Therefore, as shown in FIG. (The distance by which the sleeve protrusion 41 is restricted by the sleeve receding restriction step 23c).

On the other hand, when the slider 3 retreats, the relationship of d>a> c is established between the distances d, a, and c, so in the process of retreating the retreat distance a, which is the maximum retreat distance, first, After the engagement protrusion 35 of the slider body 31 has passed over the slider stopper 81 of the slider receiving portion 8, the rear end of the slider body 31 is
28 As shown in the figure, the slider receiving portion 8 projects from the rear end.

Here, between the rear end of the slider main body 31 and the front end (front end wall portion) 95 of the body ring 9 is the slider 3 as described above.
Since the blocked sleeve 4 and the sleeve 4 are integrally retracted, the distance b is maintained as shown in FIG.

Next, when the slider 3 is released from the surface of the sheet on which the slider 3 was pressed, the blocked sleeve 4 and the receiving portion 15 are
The urging force of the third elastic body 12 advances the tip of the receiving portion 15 until it comes into contact with the rear end of the tip tool 2. In this advance,
The lead chuck 51 holds the core S in a stuck state.
In addition, in the forward movement, the forward biasing force of the third elastic body 12 is more than the backward biasing force of the first elastic body 11 plus the frictional force generated between the stopper projection 61 and the friction step portion 43 as described above. Since it is set to be large, the above-mentioned forward movement is performed against these opposing external forces.

On the other hand, the slider 3 advances due to the forward biasing force of the first elastic body 11, but as shown in FIG. 28, by the engagement protrusion 35 of the slider body 31 engaged with the slider stopper 81 of the slider receiving portion 8, It is paused. Even when the slider 3 is temporarily stopped, as described above, the lead delivery mechanism 5
Since the core S advances forward with the core S attached, the core S contacts the slider 3 until the tip wall portion 95 of the body ring 9 contacts the rear end of the slider body 31 and the temporary stop engagement is released. Will move forward. This amount of advance is equal to the distance b.

Therefore, by this first tip knock, FIG.
= B), the core S projects a length b from the tip of the slide tip 32.

(B) Next, the second tip knocking is performed in a state where the core S projects from the tip of the slide tip 32 as shown in the 25th illustration.

In this case, when the projection amount X and the distance a-distance c have a relationship of X? Distance a-distance c, the core S protruding from the slide tip 32 by a length of X + b is always obtained.

Now, in order to facilitate understanding, a specific numerical value will be substituted as an example for description. For example, b = 0.8mm, c = 1.3mm, a =
1.7mm, X = 0.3mm (<ad = 0.4mm). If the tip knock is performed in this state, first, only the blocked sleeve 4 and the receiving portion 15 together with the core S and the third elastic body 12 are attached up to the retreat distance X which is the amount protruding from the tip of the slide tip 32. It retreats against the force and the frictional force between the stopper protrusion 61 and the friction step portion 43.

After that, the slider 3 is retracted together with the blocked sleeve 4 and the receiving portion 15 as in the case of the first tip knock.
Therefore, the retracted amount of the blocked sleeve 4 is larger than the slider 3 by X = 0.3 mm. Therefore,
The retractable distance of the slider 3 is the sleeve retreat regulation step
Due to the relationship with the sleeve 4 whose amount of retreat is restricted to 23c, only a-X = 1.7 mm-0.3 mm = 1.4 mm can be retreated.
Then, in the retracting process, the engaging projection 35 of the slider 3 gets over the slider stopper 81 of the slider receiving portion 8.

As described above, since the retracted amount of the blocked sleeve 4 is larger than that of the slider 3 by X = 0.3 mm, the distance between the tip wall portion 95 of the body ring 9 and the rear end of the slider body 31 is b + X. Become.

Next, when the slider 3 is released from the surface of the sheet on which the slider 3 has been pressed, the blocked sleeve 4 moves forward with the core S stuck to it, as in the case of the above-described first tip knock.

On the other hand, the slider 3 is temporarily stopped by the slider stopper 81 that engages with the engagement protrusion 35.

Therefore, thereafter, the core S is projected to the slider 3 in the same manner as the first tip knock. That is, even when the slider 3 is temporarily stopped, the lead delivery mechanism 5 moves forward with the lead S attached, so that the front end wall portion 95 of the body ring 9 abuts on the rear end of the slider body 31, and The core S advances with respect to the slider 3 until the stop engagement is released. This advance amount is equal to b + X as described above.

Therefore, the second tip knock returns to the state shown in the twenty-fifth figure, and the core S is moved from the tip of the slide tip 32 to X + b.
It is possible to obtain a projecting length.

On the other hand, when X> a-c = 0.4 mm, the slider 3
Cannot be retracted until it can be engaged with the slider stopper 81 by the sleeve 4 which is regulated by the sleeve receding regulation step 23c. Therefore, the slider 3 is engaged with the slider stopper 81 of the slider receiving portion 8 and cannot be temporarily stopped, so that the above-described protrusion amount is not adjusted. In other words, no matter how many times the tip knock is performed, the tip knock without the core feed is repeated,
This means that the core S projects in a state where the projection amount X is always unchanged and remains unchanged.

As described above, in this embodiment, since the engagement between the slider 3 and the slider receiving portion 8 is released by pressing and abutting the tip wall portion 95 of the body ring 9, the slide tip 32 is projected from the tip tool 2. With this, a reliable tip knock can be performed.

As described above, three types of lead feeding operations can be performed. And
During writing, the blocked sleeve 4 and the receiving portion 15 of the lead feeding mechanism 5 and the like that is sticking the lead S are urged forward by the third elastic body 12. Therefore, when excessive writing pressure acts on the core S during writing, the blocked sleeve 4 and the receiving portion 15 compress the third elastic body 12 and retract, so that the mechanical pencil absorbs excessive writing pressure. Have a function.

Next, the lock storage operation of the slider 3 of the mechanical pencil according to the present invention will be described with reference to FIGS. 1 and 29.

From the state where the slider 3 is not locked, the core pipe 13
The rear end is knocked (rear end knock) (in this case, the lead chuck 51 opens the core S. Therefore, the blocked sleeve 4 does not move rearward unlike the above-described front knock. ), And the slide chip 32 is pressed against the paper surface or the like. By this operation, the slider 3 retracts while compressing the first elastic body 11. In the backward movement process, the slider 3 is engaged with the slider stopper 81, the rear end portion thereof is housed in the body ring 9, and is engaged with the tip engaging portion 96 of the body ring 9.

Here, the above-described normal core feeding is performed by the trailing end knock, but at the final stage, the leading end of the lead chuck 51 pushes the protruding bar 10 forward. Due to the forward movement of the protrusion bar 10, the slit of the body ring 9
Since 92 is pushed out and the opening area of the tip portion of the body ring 9 is enlarged, the vicinity of the rear end portion of the retracted slider 3 can be smoothly stored in the body ring 9.

Therefore, by storing the slider 3 in the body ring 9, a lock storage space for the slider 3 is secured, and when the slider 3 is locked, a very small portion of the slide chip 32 projects from the tip of the tip tool 2. The slider 3 can be efficiently locked and stored without being overloaded.

Next, the unlocking of the slider 3 and the lead-out operation will be described.

For the unlocking and the lead-out, it is sufficient to knock the rear end. When the rear end knock is performed, the sleeve 4 and the lead delivery mechanism 5 both advance by the distance b. In the process of moving forward,
As shown in FIGS. 1 (A) (ii) and 1 (B) (ii), the tip wall portion 95 of the body ring 9 is engaged with the engaging recess of the slider 3.
Since the inclined surface portion 36a of the slider 36 is pressed and the first elastic body 11 also biases the slider 3 forward by the compressive elastic force, the engagement protrusion 35 of the slider 3 and the slider stopper 81 are engaged. And the engagement between the tip engaging portion 96 of the body ring 9 and the engaging concave portion of the slider 3 is released.

Here, as the means for releasing the engagement, the tip wall portion 106 of the protruding bar 10 may be further added.

 Next, the normal core feeding by the rear end knock is performed.

After that, the slider 3 is moved by the first elastic body 11.
It returns to the state of FIG. 25 and writing is possible.

FIG. 30 shows another embodiment in which the joint 7 and the core pipe 13 are integrally formed.

Although not shown, in the first embodiment, the chuck opening / closing mechanism 14 at the tip of the core pipe 13 may be omitted, and the tip of the core pipe 13 may be directly attached to or detached from the joint 7.

FIG. 31 shows another embodiment of the present invention. That is, the tip tool 2 is divided into two parts, the tip tool body 2A and the connecting tube 2B, to form the tip tool. The connecting tube 2B has a tip connecting section 21B ₁ and an outer tube connecting section 21B ₂ on the tip side. A rear end cylinder portion 22B is continuously provided at the rear end of the outer cylinder connection portion 21B ₂ . This rear cylinder portion 22B has the same structure as the rear cylinder portion 22 of the embodiment shown in FIG. That is, it has a pair of sliding grooves 23 and slits 24 shown in FIGS. As shown in FIGS. 1 to 5, the pair of sliding grooves 23 have a sleeve projection sliding groove 23a, a stopper projection sliding groove 23b, and a sleeve retreat restricting step portion 23c.

Also, the slide tip of the slider 3 shown in FIG.
A slide pipe 32a having a smaller diameter than 32 and formed of, for example, an extruded pipe, is fitted to the tip of the slider body 31, and can be applied as a mechanical pencil for drawing.

〔The invention's effect〕

As described above, according to the present invention, by assembling the other parts of the mechanical pencil excluding the outer cylinder into blocks, the assembly work and the like can be simplified, the number of parts is reduced, and the parts efficiency is improved by the multipurpose use of the parts. Efficiency can also be achieved. In addition, since the core is always covered with parts such as a protruding bar, it is possible to prevent core breakage and stabilize the quality. Furthermore, three types of lead feeding operations can be performed, and if the slide tip projects from the tip, the tip can be knocked reliably. Further, since the slider housing space is provided especially in the body ring, there is an excellent effect that the slider can be locked and housed securely.

[Brief description of drawings]

FIG. 1 (A) is a vertical cross-sectional view of an embodiment of the present invention, FIG. 1 (B) is a vertical cross-sectional view of the main part, FIG. 2 is a plan view of a tip, and FIG.
FIG. 4 is a sectional view taken along the line AA of FIG. 2, FIG. 4 is a rear view of FIG. 2, FIG. 5 is an explanatory perspective view of a sliding groove of a tip tool, FIG. 6 is a plan view of a slider, and FIG. 6 is a sectional view taken along the line BB of FIG. 6, FIG. 8 is a rear view of FIG. 6, and FIG. 9 is a plan view of a sleeve.
10 is a sectional view taken along the line CC of FIG. 9, FIG. 11 is a rear view of FIG. 9, FIG. 12 (A) is a front view of the trunk ring, and FIG. 12 (B) is a sectional view taken along the line DD. Fig. 13, Fig. 13 (A) is a plan view of the protruding bar, Fig. 13 (B) is a sectional view taken along the line EE, Fig. 14 is a longitudinal sectional view of the lead chuck, and Fig. 15 is an arrow view of Fig. 14. FIG. 16 is a sectional view taken along the line 15-F of FIG. 17, FIG. 17 is a sectional view taken along the line GG of FIG. 15, FIG. 18 is a sectional view taken along the line HH of FIG. 14, and FIG. Enlarged plan view of the teeth, Fig. 20 and Fig. 21 are enlarged explanatory views of the teeth, Fig. 22
Figures 24 to 24 are longitudinal sectional views of the lead chuck head of another embodiment, and Figures 25 to 29 are explanatory views of the lead feeding operation and the locking operation,
FIG. 30 is a vertical sectional view of an outer cylinder portion of another embodiment, and FIG. 31 is a vertical sectional view of another embodiment. 1 is an outer cylinder, 2 is a tip tool, 3 is a slider, 4 is a sleeve,
5 is a lead feeding mechanism, 6 is a stopper, 9 is a body ring, 10 is a protruding bar, 11 and 12 are elastic bodies, and S is a lead.

Claims (1)

(57) [Claims] A tip tool (2) removably fitted to the tip of an outer cylinder (1), a sleeve (4) slidably engaged with the tip tool (2), The lead (5) is mounted inside the sleeve (4) and allows the lead (S) to move forward, but prevents the lead (S) from moving backward. A body ring (9) for unlocking, which has a storage space, a protruding bar (10) which is arranged in the body ring (9) and covers and covers the core (S), and in the tip tool (2). A slider (3) slidably disposed on the core (S), having a locking engagement part (35) that can be engaged with and disengaged from the tip (2), and imparting a predetermined frictional force to the core (S). And is elastically fitted between the slider (3) and the protruding bar (10), and the core feeding force of the lead feeding mechanism (5) Elastic body having a biasing force have (1
1), a stopper (6) slidably engaged with the tip tool (2) and the sleeve (4), and an elastic body for urging the tip tool (2) and the sleeve (4) forward. (12)
Mechanical pencil with and.