KR102299962B1 - Ballpoint pen chip and writing utensil equipped with the ballpoint pen chip - Google Patents

Abstract

Make it easy to change the width of the writing line.
The transfer ball 20 is brought into contact with the inner annular protrusion 11a1 of the tip body 10 from the rear side, and the second half side of the transfer ball 20 is accommodated by the receiving member 30, the receiving member Reference numeral 30 has a reduced portion 31 whose cross-sectional area is gradually reduced toward the front, and the frontmost end of the reduced portion 31 is disposed behind the transfer ball 20 , and is rearward than the reduced portion 31 .側) is fixed so as not to retreat to the tip body 10, and the inner wall of the tip body 10 is provided with a bending restraining protrusion 15 that approaches or comes into contact with the reduced portion 31.

Description

Ballpoint pen tip and writing instrument equipped with the ballpoint pen tip

The present invention relates to a ballpoint pen tip configured to change the width of a writing line, and a writing instrument having the ballpoint pen tip.

Conventionally, as described in Patent Document 1, for example, in a writing instrument of this type, there is one that adjusts the relative position of the body member that accommodates the ball from the rear side. According to this writing instrument, when the relative position of the sealing member is changed by adjusting the screw tightening amount of the tip or the sealing member or the rotation amount of the movement control member, the gap between the ball and the inner edge of the small mouth of the tip is changed. Therefore, the ink ejection amount also changes, and as a result of this, the width of the writing line also changes.

Also, as another prior art, there is a case in which the line width is changed by adjusting the inclination angle of the tip with respect to the surface to be written (see Patent Document 2).

Japanese Laid-Open Patent Publication No. 2004-1246 Japanese Patent Laid-Open No. 2013-252654

However, in the prior art of Patent Document 1, it is necessary to adjust the relative position of the sealing member in order to change the width of the writing line, and the adjustment operation is cumbersome. Moreover, in the prior art of patent document 2, in order to change the inclination angle of a writing instrument, the writing posture may become disturbed.

In view of such a subject, this invention is provided with the following structures.

A substantially cylindrical tip body penetrating the inside in the front-rear direction, and a transfer ball accommodated in a front end side in the tip body and projecting an outer circumferential front end side forward from the tip body; A ballpoint pen tip having a receiving member disposed on a rear side of the transfer ball in a tip body, wherein a rear end side of the transfer ball is received by a front end of the receiving member, wherein the receiving member is on the front end side has a reduced portion in which the cross-sectional area is gradually reduced toward the front, the front end of the reduced portion is disposed behind the transfer ball, and a portion rearward than the reduced portion is fixed to the tip body in a non-retractable manner is configured to elastically contract when receiving a pressing force from the transfer ball, and on the inner wall of the tip body, close to or in contact with the sidewall of the reduced portion to suppress the bending of the reduced portion Ballpoint pen tip, characterized in that provided with a restraining projection.

Since the present invention is configured as described above, the width of the written line can be easily changed.

1 is a longitudinal sectional view showing a first embodiment of a ballpoint pen tip according to the present invention.
Fig. 2 shows an example of the accommodating member, Fig. 2 (a) is a view seen from the front, Fig. 2 (b) is a half sectional view, and Fig. 2 (c) is a view seen from the rear.
FIG. 3 is a cross-sectional view taken along line (III)-(III) in FIG. 1 .
Fig. 4 is a longitudinal sectional view of the main part of the tip body in a state in which the distal end is not caulked.
Fig. 5 is a view of the tip body in a state in which the distal end is not caulked, as viewed from the front side;
Fig. 6 is a perspective view showing a longitudinal section of the main part of the tip body in a state in which the distal end is not caulked.
7 is a longitudinal cross-sectional view of a writing instrument having a ballpoint pen tip according to the present invention.
Fig. 8 is a sectional view of the main part showing the use state of the writing instrument.
9 is a longitudinal sectional view showing a second embodiment of a ballpoint pen tip according to the present invention.
Fig. 10 is a longitudinal sectional view showing a third embodiment of a ballpoint pen tip according to the present invention.
In Fig. 11, Fig. 11(a) is a cross-sectional view taken along the line (a)-(a) in Fig. 10, and Fig. 11(b) is a cross-sectional view taken along the line (b)-(b) in Fig. 10 . .
Fig. 12 is a cross-sectional view taken along the line (c)-(c) in Fig. 10 .
It is a perspective view which shows the front side member of the accommodation member in 3rd Embodiment.
It is a perspective view which shows the rear side member of the accommodation member in 3rd Embodiment.
Fig. 15 is a longitudinal sectional view showing a fourth embodiment of a ballpoint pen tip according to the present invention.
Fig. 16 is a cross-sectional view taken along the line (XV)-(XV) in Fig. 15 .
It is a perspective view which shows the accommodation member in 4th Embodiment.
18 is a longitudinal sectional view showing a fifth embodiment of a ballpoint pen tip according to the present invention.
Fig. 19 is an enlarged view from the front, with the transfer ball omitted, for the fifth embodiment.
It is an enlarged view of the principal part in 5th Embodiment.
Fig. 21 is a cross-sectional view taken along the line (XXI)-(XXI) in Fig. 20, Fig. 21 (a) shows a normal state, and Fig. 21 (b) shows the radially bent and reduced portion is accommodated by the bending restraining projection. indicates the status of

The first feature of the present embodiment is a substantially cylindrical tip body penetrating the inside in the front-rear direction, and a transfer ball accommodated on the front end side in the tip body and projecting the front end side of the outer circumferential surface forward from the tip body; , a ballpoint pen tip having a receiving member disposed in a rearward direction from the transfer ball in the tip body, wherein the latter part of the transfer ball is accommodated by the front end of the receiving member, the receiving member comprising: On the front end side, there is a reduced portion in which the cross-sectional area is gradually reduced toward the front, the front end of the reduced portion is disposed behind the transfer ball, and a portion rearward than the reduced portion is fixed to the tip body so as not to retract, When a pressing force is received from the transfer ball, it is elastically contracted.

According to the above configuration, the reduction portion prevents the front end side of the housing member from being bent in the radial direction, and a writing line having a thickness corresponding to the pressing force can be stably obtained.

In addition, the "reduction part" does not include a coil spring.

As a second feature, in order to more effectively suppress bending of the front end side of the accommodation member in the radial direction, the reduced portion is formed into a solid shape in which the cross-sectional area is continuously enlarged from the front end of the accommodation member toward the rear. formed

Here, the "solid shape" means a shape having no hollow part therein.

Moreover, as a specific example of the said reduced part, the aspect of a truncated cone shape, the aspect of a truncated pyramid shape, etc. are mentioned.

As a third feature, in order to sufficiently secure an ink flow path in the tip body and to provide good manufacturability, the receiving member has a support protrusion protruding in a radially outward direction at a rear side of the reduced portion in a circumferential direction. It has a plurality of spaced apart from each other, and these supporting projections are pressed against the inner wall surface of the tip body and fixed so as not to be retracted.

As a fourth characteristic, the accommodating member was integrally formed of one type of synthetic resin material so as to obtain a soft feel (see Figs. 1 and 9).

As a fifth feature, in order to effectively elastically deform the accommodating member and to improve productivity, the accommodating member is composed of two members: a front member having the reduced portion and a rear member having the support protrusion (Fig. 10). and Figure 15).

As a sixth characteristic, in order to improve quality and productivity, the rear member is made of a material having a higher abrasion resistance than that of the front member.

As a seventh feature, in order to elastically deform the housing member more effectively and to facilitate line width adjustment, the front member is formed of a material that is more easily elastically deformed than the rear member.

As an eighth feature, in order to elastically deform the receiving member more effectively and improve productivity, the transfer ball and the rear member are loosely fitted with the front member to the inner circumferential surface of the tip body. placed in between.

As a ninth feature, in order to reduce the flow resistance of ink in the tip body, a plurality of vertical ribs extending in the front-rear direction are provided on the outer periphery of the front member at a rear side from the reduced portion at intervals in the circumferential direction, and these vertical ribs are provided. The number and the number of the support protrusions were different (see FIG. 12 ).

The tenth feature is a preferable aspect with good productivity, wherein the front member and the rear member are connected and integrated (see FIG. 15 ).

In the eleventh feature, in order to prevent the reduced portion from being bent in the radial direction, a bending restraining projection is provided on the inner wall of the tip body to suppress the curvature of the reduced portion by coming into close contact with or in contact with the sidewall of the reduced portion (Figs. 18 to 18). 21).

A twelfth feature is that, in order to stabilize the ink flow rate, a plurality of the curvature suppressing protrusions are provided at intervals in the circumferential direction, and the ink guide grooves in which the curvature suppressing protrusions adjacent in the circumferential direction communicate in the front-rear direction. ) (see FIGS. 19 and 20).

A thirteenth feature is that, in order to further stabilize the ink flow rate, a constriction portion is provided on the front end side within the tip body to receive the transfer ball when retracted by the front end surface, and the bending restraining projection is rearward than the front end surface of the constriction portion. placed on the side.

As a fourteenth feature, the front and rear positions of the constriction are set so that the received transfer ball protrudes forward from the front end of the tip body (see Fig. 20).

A fifteenth feature, in particular, in order to effectively prevent ink leakage, arrange a coil spring in an annular shape around the reduced portion, abut the front end of the coil spring to the transfer ball, and retract the rear end of the coil spring impossibly supported (see FIG. 9).

A sixteenth feature is that, in order to sufficiently secure an ink flow path in the tip body and to improve quality and productivity, a square cylindrical inner wall surface is formed on the front end side of the tip body, and the square cylindrical inner wall surface is transferred to the It was made to approach or contact the outer peripheral surface of the ball (refer to FIG. 3).

According to the seventeenth feature, a writing instrument is constituted by including the ballpoint pen tip (see FIG. 7 ).

Next, the specific embodiment which has the said characteristic is demonstrated in detail based on drawing.

In addition, in this specification, "front" means the tip direction of a ball-point pen tip, and "rear" means the opposite direction. In addition, the "outward-diameter direction" means a direction away from the center in the radial direction of the ball-point pen tip, and the "inward-diameter direction" means the opposite direction.

<First embodiment>

1 shows a ballpoint pen tip 1 according to the present invention.

The ballpoint pen tip 1 has a substantially cylindrical tip body 10 penetrating the inside in the front-rear direction, and is accommodated on the front end side in the tip body 10, and the front end side of the tip body 10 has an outer peripheral surface front end side. The transfer ball 20 protruded forward from the tip body 10 and the receiving member 30 disposed on the rear side of the transfer ball 20 in the tip body 10 is provided.

This ball-point pen tip 1 abuts against the inward annular protrusion 11a1 on the front end side of the tip body 10 from the rear side thereof, and the transfer ball 20 The latter part is accommodated by the front end of the substantially rod-shaped accommodating member 30 without being accommodated on the inner surface of the tip body 10 in the initial state.

In addition, the ballpoint pen tip 1 has an inner wall surface on the front end side of the tip body 10 formed in a square cylindrical shape, and the outer peripheral surface of the transfer ball 20 is brought into close contact with or brought into contact with the square cylindrical inner wall surface 11b. making it happen

The tip body 10 is made of, for example, an alloy or synthetic resin such as stainless steel, brass, or silver, and is formed in a substantially cylindrical shape having a conical portion tapering to the tip side.

In this tip body 10, a ball house 11, a constriction 12, a tapered hole 13, and a large-diameter hole 14 are provided in order from the front end side, and their internal space is in the front-rear direction. is connected

The ball house 11 has an inner annular protrusion 11a1 at the frontmost side, a rectangular cylindrical inner wall face 11b extending rearward from the inner annular protrusion 11a1, and a front end face of the constriction 12 . This constitutes a space for rotatably accommodating the transfer ball 20 .

The inner annular protrusion 11a1 is formed by caulking the front end of the tip body 10 from the outside after the transfer ball 20 is inserted into the ball house 11 .

That is, in the previous stage in which the transfer ball 20 is inserted, a cylindrical inner peripheral surface 11a is formed on the frontmost side of the ball house 11 as shown in FIG. 4 . After the transfer ball 20 is inserted into the ball house 11, the peripheral wall of the cylindrical inner peripheral surface 11a is caulked from the outside, whereby an inner annular projection 11a1 is formed on the front end side of the cylindrical inner peripheral surface 11a. do. The inner annular protrusion 11a1 is made to protrude radially inward from the cylindrical inner peripheral surface 11a, and is brought into contact with the first half of the transfer ball 20 .

The square cylindrical inner wall surface 11b is an inner wall surface of a regular polygonal cylindrical shape (a regular spherical cylindrical shape according to the example of illustration). Each surface constituting this rectangular cylindrical inner wall surface 11b is formed in a flat surface shape. And the inner corner-shaped part 11c is formed between the surfaces adjacent to the circumferential direction among the several surfaces which comprise the square cylindrical inner wall surface 11b.

Further, the constricted portion 12 is substantially constricted (or protruded in the diameter inward direction) by reducing the diameter of the portion behind the tubular inner wall surface 11b to an inner diameter smaller than the minimum diameter of the prismatic inner wall surface 11b. annular protrusion shape) (refer to FIGS. 1 and 4). The inner peripheral surface of the hole penetrating through the constriction 12 is a substantially cylindrical surface, and an ink guide groove 12a (refer to Fig. 5) penetrating in the front-rear direction is formed on the surface. The distribution cross-sectional area of the ink guide groove 12a is set so that an ink flow amount may be ensured appropriately.

The constriction 12 of the above configuration is set to have an inner diameter smaller than the outer diameter of the transfer ball 20 so as not to insert the transfer ball 20 backward.

Moreover, as another example other than the example of illustration, it is also possible to abbreviate|omit the constriction part 12, and to set it as the shape which connected the square cylindrical inner wall surface 11b to the front end side of the taper hole 13. As shown in FIG.

A tapered hole 13 is provided on the rear side of the constriction 12 .

The tapered hole 13 is a substantially truncated cone-shaped hole continuously reduced in diameter toward the front, and accommodates the reduced portion 31 of the accommodating member 30 described later, and the space around the reduced portion 31 . is the ink distribution path. On the rear end side of this data hole 13, a large-diameter hole 14 is continuous.

The large-diameter hole 14 is formed in a substantially cylindrical shape continuous backward from the rear end of the tapered hole 13 . A housing member 30 is inserted into the large-diameter hole 14 , and a plurality of supporting projections 32 on the rear side of the housing member 30 are press-contacted and fixed to the inner wall surface of the large-diameter hole 14 .

This large-diameter hole 14 uses a plurality of drills whose diameters have been reduced step by step, to form holes that are gradually reduced in diameter toward the front, and then, by finishing processing such as reaming, have the same diameter continuous in the front-rear direction. machined in the hole. In addition, as another example other than the illustrated example, it is also possible to omit the finishing process and make the large-diameter hole 14 into a hole whose diameter is reduced in steps toward the front.

In addition, the transfer ball 20 is formed in a spherical shape from a hard metal material such as a sintered body containing, for example, tungsten carbide or silicon carbide as a main component, or a synthetic resin material, and is accommodated in the ball house 11 .

The front end side of the transfer ball 20 is pressed against the inner annular projection 11a1 on the front end side inside the ball house 11 . And the latter part side of the transfer ball 20 is not accommodated in the front end surface of the constriction 12 which is the inner surface of the tip main body 10, but is accommodated only by the front end surface of the accommodation member 30. As shown in FIG. That is, a gap is secured between the front end face of the constriction 12 and the rear end side of the transfer ball 20 (refer to FIG. 1 ), and the front end face of the receiving member 30 is the rear end face of the transfer ball 20 . is approaching

In addition, when writing is performed with normal pen pressure, the transfer ball 20 is not accommodated in the inner surface of the tip body 10 but is accommodated by the front end of the substantially rod-shaped accommodating member 30 (see FIG. 8 ). ), but the pen pressure is too strong, and when a strong pressing force is received from the rear, the tip body 10 may come into contact with the constriction 12 of the inner surface.

The outer diameter of the transfer ball 20 is set to a diameter slightly smaller than that of an imaginary sphere in contact with the cylindrical inner wall surface 11b of the ball house 11 . Therefore, the outer peripheral surface of the transfer ball 20 approaches each surface which comprises the square cylindrical inner wall surface 11b (refer FIG. 3).

In addition, the transfer ball 20 may be slightly eccentric with respect to the center of the tip body 10 due to non-uniformity of the dimensional accuracy of the inner surface of the ball house 11, etc. In such a case, the transfer ball 20 ) may be in contact with the surface constituting the rectangular cylindrical inner wall surface 11b.

Moreover, as shown in FIG. 3, in the periphery of the transfer ball 20, the inner corner-shaped part 11c is formed between the flat surface parts adjacent to the square cylindrical inner wall surface 11b. This inner corner-shaped portion 11c secures a gap s1 serving as an ink flow path.

In addition, the receiving member 30 has, on its front end side, a reduced portion 31 whose cross-sectional area is gradually reduced toward the front, and the frontmost end of the reduced portion 31 is disposed behind the transfer ball 20 , have. In addition, the receiving member 30 has a plurality (three according to the illustrated example) of the support protrusions 32 protruding in the radial outward direction at intervals in the circumferential direction, behind the reduced portion 31, and supporting these By pressing the protrusion 32 to the inner wall surface of the tip body 10, it is fixed so as not to advance and retreat.

The receiving member 30 is integrally formed from one type of elastically deformable hard synthetic resin material such as POM (polyacetal), PE (polyethylene), PP (polypropylene), and the like, and is formed in a rod shape from the transfer ball 20 . It is elastically contracted by the applied pressure.

The reduced portion 31 is formed in the shape of a truncated cone in which the outer diameter is continuously enlarged from the contact surface with the transfer ball 20 toward the rear.

As shown in FIG. 2, the support protrusion 32 protrudes substantially radially, and is provided in plurality (three according to the example of illustration). The plurality of support protrusions 32 are formed when the receiving member 30 is inserted into the tip body 10 from the rear side of the tip body 10 in the manufacturing stage of the ballpoint pen tip 1, the tip body ( 10) is pressed against the inner circumferential surface.

In FIG. 2 , reference numeral 32a denotes a tapered surface that facilitates the insertion operation, and each tapered surface 32a is formed on the front end side of each support protrusion 32 .

And the space between the supporting projections 32 and 32 adjacent in the circumferential direction functions as an ink flow path.

Next, the writing instrument 100 using the ballpoint pen tip 1 of the above configuration will be described (see FIG. 7 ).

The writing instrument 100 protrudes the ballpoint pen tip 1 of the front end of the ballpoint pen refill 120 from the front end of the shaft 110 by the pressing operation of the knock unit 140, and the protruding state is determined by setting the clip 111 to the center of the shaft. It is a retractable ballpoint pen that is released by bending it to the side.

The ballpoint pen refill 120 is made by connecting the ballpoint pen tip 1 to the front end of the ink receiving tube 121 and filling the inside of them with ink.

Next, the effect of writing by the ballpoint pen tip 1 and the writing instrument 100 (ballpoint pen) having the above configuration will be described.

As shown in FIG. 8 , when a rearward pressing force is applied to the transfer ball 20 by pressing the front end side of the transfer ball 20 against the surface to be written, the receiving member 30 becomes elastic in the axial direction. , the transfer ball 20 retracts slightly. For this reason, a gap is formed between the transfer ball 20 and the inner annular projection 11a1, and ink is discharged from the gap. In addition, when the pressing force decreases, the receiving member 30 is restored to its original length, and the transfer ball 20 advances to narrow the gap.

Therefore, when the pressing force is relatively large, the amount of contraction of the receiving member 30 and the amount of retreat of the transfer ball 20 are large, and the gap between the transfer ball 20 and the inner annular projection 11a1 is widened, so that the ink As the discharge amount increases, the writing line becomes thicker.

In addition, when the pressing force is relatively small, the amount of contraction of the receiving member 30 and the amount of retreat of the transfer ball 20 are small, and the gap between the transfer ball 20 and the inner annular projection 11a1 is narrowed. The amount of ink ejected decreases and the writing line becomes thinner.

When writing is performed in a normal writing posture, the front end side of the accommodating member 30 receives a pressing force in a direction inclined with respect to the centerline direction of the accommodating member 30 due to the writing angle at the time of writing. There is (see FIG. 8).

According to the ballpoint pen tip 1 of this embodiment, since the front end side of the receiving member 30 has a reduced portion 31 that gradually reduces the cross-sectional area toward the front, even when the pressing force in the inclined direction is received as described above, The front end side of the accommodating member 30 is hardly bent in the radial direction, and is elastically contracted in the axial direction.

That is, if the front end side of the receiving member 30 is formed in a straight rod shape, the front end side portion is bent in the radial direction to shift from the center of the transfer ball 20 , and the transfer ball 20 is retracted. Although there is a possibility that the amount is unstable, the ink discharge amount and the thickness of the writing line are also unstable, according to the present invention, such a problem is prevented and writing lines having a thickness according to the pressing force can be stably obtained.

Also, around the transfer ball 20, a gap s1 is secured by the inner corner-shaped portion 11c of the rectangular cylindrical inner wall surface 11b, so this gap s1 serves as an ink flow path. , to keep the ink flow rate stable.

In addition, since the outer peripheral surface of the transfer ball 20 is in point contact with the flat surface constituting the rectangular cylindrical inner wall surface 11b, for example, the prior art in which the outer peripheral surface of the transfer ball is brought into contact with the cylindrical surface. Compared with the like, the rotational resistance of the transfer ball 20 can be reduced.

Next, another example of the ballpoint pen tip according to the present invention will be described.

In addition, since a part of the ball-point pen tip shown below is changed with respect to the above-mentioned ball-point pen tip 1, the changed part will be mainly described in detail, and overlapping detailed description will be abbreviate|omitted.

<Second embodiment>

The ball-point pen tip 2 shown in Fig. 9 has a configuration in which a coil spring 40 is added to the ball-point pen tip 1 described above.

More specifically, the ballpoint pen tip 2 has a coil spring 40 disposed around the reduced portion 31 of the receiving member 30 in an annular shape, and the front end of the coil spring 40 is transferred to a ball While making contact with (20), the rear end of the coil spring (40) is supported non-retractable by the step on the rear end of the reduced portion (31), and the rear end of the transfer ball (20) and the reduced portion (31) are A gap s2 is secured between the front ends.

According to the ballpoint pen tip 2 having the above configuration, in an unused state in which a backward pressing force is not applied to the transfer ball 20 , the transfer ball 20 is moved by the elastic force of the coil spring 40 to protrude the inner annular shape. By press-contacting 11a1, it is possible to effectively prevent ink leakage between the transfer ball 20 and the inner annular projection 11a1.

Further, when the transfer ball 20 is pressed against the surface to be written, the transfer ball 20 is slightly retracted, so that a gap is generated between the transfer ball 20 and the inner annular projection 11a1, from the gap. Ink is ejected.

And, when the pressing force against the transfer ball 20 is relatively large, the rear end face of the transfer ball 20 comes in contact with the front end face of the receiving member 30, and the receiving member 30 is elastically contracted, The gap between the transfer ball 20 and the inner annular projection 11a1 becomes large, and the ink flow rate due to the gap increases, and the writing line becomes thick. In addition, when the transfer ball 20 is formed of a synthetic resin material, in addition to the shrinkage of the receiving member 30, the transfer ball 20 also tends to contract, so that the ink flow rate can be further increased.

Therefore, in this ballpoint pen tip 2 as well, similarly to the above-mentioned ballpoint pen tip 1, it can be used as a component of the writing instrument 100 (ballpoint pen), and when writing, a writing line having a thickness corresponding to the pressing force can be stably applied. can be obtained

This ball-point pen tip 2 can be used as a component of the writing instrument 100 (ball-point pen), similarly to the above-described ball-point pen tip 1 .

<Third embodiment>

In the ballpoint pen tip 3 shown in FIG. 10 , the accommodating member 30 is replaced by the accommodating member 50 with respect to the aforementioned ballpoint pen tip 1 .

In the housing member 50, two members, a front member 51 having a constricted portion 51a, and a rear member 52 having a support protrusion 52b, are brought into contact with each other in the front-rear direction.

The front member 51 has, on its front end side, a truncated cone-shaped reduced portion 51a having substantially the same shape as the aforementioned reduced portion 31, and the frontmost end of the reduced portion 51a is a transfer ball (20). is in contact with the rear end of

In addition, the front member 51 has a plurality of vertical ribs 51b extending in the front-rear direction at equal intervals in the circumferential direction on the outer peripheral portion of the axial portion rearward than the reduced portion 51a (three according to the illustrated example). ) are placed.

The vertical rib 51b is formed so as to be continuous in the front-rear direction in a state in which it is loosely fitted to the inner circumferential surface of the tip body 10 on the rear side of the reduced portion 51a of the front member 51 . A tapered surface 51b1 inclined toward the axial center is formed on the front end side of the vertical rib 51b.

In addition, although the clearance gap is shown between the vertical rib 51b and the inner peripheral surface of the tip body 10 in FIGS. It is formed to be loosely fitted in contact or close proximity. According to this configuration, the operation of inserting the front member 51 into the tip body 10 can be facilitated, and the elastic elasticity of the entire front member 51 in the axial direction can be improved.

The vertical rib 51b functions as a reinforcing rib that suppresses bending of the front member 51 in response to pen pressure or the like.

Further, the tapered surface 51b1 functions as a guide surface for inserting the receiving member 50 into the tip body 10 .

A cylindrical jig insertion hole 51c having a rear opening is provided on the rear end side of the central portion in the front member 51 .

In addition, as shown in FIG. 14, the rear member 52 has a plurality of supporting projections 52b protruding in the radial outward direction on the outer periphery of the cylindrical shaft portion 52a at equal intervals in the circumferential direction (illustration example). according to 4). This rear member 52 accommodates the rear end face of the front member 51 and press-contacts the plurality of support protrusions 52b to the inner wall face of the tip body 10 in the front-rear direction so as not to advance or retreat. It is fixed.

The number of the supporting projections 52b of the rear member 52 is set to be larger than the number of the longitudinal ribs 51b of the front member 51 (refer to FIG. 12 ).

The front member 51 having the above configuration is made of a material that is more elastically deformed than the rear member 52 . In addition, the rear member 52 is formed of a material having a higher wear resistance than the front member 51 .

In a preferred example of this embodiment, the front member 51 is formed of PE (polyethylene resin), and the rear member 52 is formed of POM (polyacetal resin).

For the PE, it is possible to use those having a modulus of elasticity (modulus of elasticity) of 4 to 17 [10^3 kg/cm^2], a coefficient of friction of 0.3 to 0.5, and a hardness of HDD 45 to 75.

As the POM, it is possible to use a POM having an elastic modulus of 24 to 31 [10^3 kg/cm^2], a friction coefficient of about 0.18, and a hardness of about HRR 118.

Next, in the ballpoint pen tip 3 shown in FIG. 10 , the procedure for assembling the transfer ball 20 and the receiving member 50 in the tip body 10 will be described in detail.

First, with respect to the tip body 10, the transfer ball 20 is inserted from the front, and the front end side of the peripheral wall of the ball house 11 is caulked to form the inner annular projection 11a1.

Next, with respect to the tip body 10 , the front member 51 is inserted from the rear, and the front end surface of the front member 51 (in detail, the reduced portion 51a) is the rear end of the transfer ball 20 . come into contact with

The operation of inserting the front member 51 into the tip body 10 is performed by inserting a rod-shaped jig (not shown) into the jig insertion hole 51c of the front member 51 as an example. The jig is taken out after the insertion operation. As another example, it is also possible to insert the front member 51 into the tip body 10 without using the jig insertion hole 51c and the jig.

Next, the rear member 52 is press-fitted against the tip body 10 from the rear. The press-fitted rear member 52 has its front end in contact with the rear end of the front member 51 . Accordingly, the front member 51 is in a state sandwiched by the transfer ball 20 and the rear member 52 from the front-rear direction.

The pressing force at the time of press-fitting is that the transfer ball 20 is pressed against the receiving member 50 and pressed against the inner annular protrusion 11a1 to prevent ink leakage, and the transfer ball 20 rotates smoothly, It is set appropriately so that writing is easily possible through an appropriate and appropriate pen pressure.

Accordingly, in the ballpoint pen tip 3 having the above configuration, similarly to the ballpoint pen tip 1 described above, it can be used as a part of the writing instrument 100 (ballpoint pen). can be obtained stably.

In addition, since the rear member 52 is made of a material having higher wear resistance than the front member 51, when it is press-fitted into the tip body 10, the support protrusion 52b of the rear member 52 is not cut. It is difficult, and furthermore, it is possible to prevent foreign substances such as cutting debris from remaining in the tip body 10 and to stabilize the fitting force between the receiving member 50 and the tip body 10 so as not to decrease, and also Workability at the time of the said press-fitting can be improved.

In addition, since the front member 51 is formed of a material that is more elastically deformed than the rear member 52, the portion of the front member 51, particularly the reduced portion 51a, can be effectively contracted by pen pressure. Therefore, it is possible to easily adjust the line width by adjusting the pen pressure.

In addition, in this ballpoint pen tip 3, the number of vertical ribs 51b of the receiving member 50 and the number of supporting projections 52b of the rear member 52 are different, so that the resistance of the ink flow path is reduced. are doing

That is, the front member 51 may rotate in an assembly operation or the like. However, if the vertical ribs 51b and the supporting protrusions 52b are the same number, the front between the adjacent supporting protrusions 52b and 52b. In this case, when the rear end of the vertical ribs 51b is located, the ink flowing forward receives a large resistance from the rear end of each of the vertical ribs 51b.

However, according to the ballpoint pen tip 3 of this embodiment, as shown in FIG. 12, between adjacent vertical ribs 51b and 51b and between adjacent supporting projections 52b and 52b communicate in the axial direction. Since it becomes easy to secure the ink flow resistance, it is possible to reduce the ink flow resistance.

<Fourth embodiment>

In the ballpoint pen tip 4 shown in FIG. 15 , the accommodating member 30 is replaced by the accommodating member 60 with respect to the above-described ballpoint pen tip 1 .

The accommodating member 60 is integrally constituted by two members: a front member 61 having a constricted portion 61a and a rear member 62 having a support protrusion 62a.

The front member 61 is formed only of the reduced portion 61a having substantially the same shape as the reduced portion 31 (refer to FIG. 1) of the ballpoint pen tip 1 above.

The rear member 62 is formed in substantially the same shape as the portion on the rear side of the reduced portion 31 of the ballpoint pen tip 1, and is formed of a plurality (three according to the example shown) spaced at equal intervals in the circumferential direction. It has a support protrusion 62a.

The front member 61 is made of the same material (PE) as the front member 51 of the ballpoint pen tip 3, and the rear member 62 is made of the same material as the rear member 52 of the ballpoint pen tip 3 ( POM).

That is, the front member 61 is formed of a material that is more elastically deformed than the rear member 62 , and the rear member 62 is formed of a material having higher wear resistance than the front member 61 .

These front side members 61 and rear side members 62 are integrally connected by two-color molding (double molding) to constitute the housing member 60 .

Moreover, as another example, it is also possible to provide a recessed part in the front end of the rear side member 62, and to set it as the aspect which fitted or screwed the front side member 61 into the recessed part.

In addition, in FIG. 15, reference numeral 62a1 denotes a tapered surface that facilitates the insertion operation into the tip body 10 . Moreover, the code|symbol 62c is a jig insertion hole for inserting a jig, and is used as needed.

When explaining the manufacturing procedure of the ballpoint pen tip 4, the transfer ball 20 is inserted into the front end side of the tip body 10, the front end side of the tip body 10 is caulked, and then the tip body 10 is The receiving member 60 is press-fitted from the rear direction. This operation is performed by inserting a rod-shaped jig (not shown) into the jig insertion hole 62c on the rear end side of the accommodating member 60 .

The pressing force at the time of press-fitting is that the transfer ball 20 is pressed against the receiving member 60 and pressed against the inner annular protrusion 11a1 to prevent ink leakage, and the transfer ball 20 rotates smoothly, It is set appropriately so that writing is possible easily through an appropriate and appropriate pen pressure.

Therefore, in the ballpoint pen tip 4 having the above configuration, similarly to the ballpoint pen tip 1 described above, it can be used as a part of the writing instrument 100 (ballpoint pen). can be obtained stably.

In addition, since the rear member 62 is formed of a material having higher wear resistance than the front member 61, when it is press-fitted into the tip body 10, the support protrusion 62a of the rear member 62 is not cut. It is difficult, and furthermore, while preventing foreign substances such as cutting chips from remaining in the tip body 10 , it is possible to improve workability at the time of the press-fitting.

In addition, since the front member 61 (reduced portion 61a) is made of a material that is more elastically deformed than the rear member 62, the front member 61 (reduced portion 61a) is subjected to pen pressure. can be effectively contracted, and it is possible to easily adjust the line width by adjusting the pen pressure.

<Fifth embodiment>

In the ballpoint pen tip 5 shown in Fig. 18, the tip main body 10 is substituted for the tip main body 10' with respect to the aforementioned ballpoint pen tip 4 (see Fig. 15).

The tip body 10' is provided with a bending restraining protrusion 15 and an ink guide groove 15b with respect to the tip body 10 described above, and the constricted portion 12 is moved forward.

More specifically, in the ball house 11 on the front end side in the tip body 10', there is a constriction 12 reduced in diameter so as to accommodate the transfer ball 20 when it is retracted by the front end face 12b. prepared (see FIG. 20).

The tip body 10' has, on an inner wall of the constricted portion 12 on the rear side from the front end face 12b, a bending restraining protrusion 15 for suppressing bending of the constricted portion 61a in the radial direction.

The front end surface 12b of the constriction 12 is a substantially bowl-shaped surface which inclines backward as it approaches a center part.

The constricted portion 12 is configured to project the transfer ball 20 forward by the dimension P from the front end of the tip body 10' in a state that accommodates the transfer ball 20 when it is retracted. , the front and rear positions are set.

The dimension P is such that, when writing is performed at a normal writing angle (60 to 90 degrees) by bringing the outer peripheral surface of the front end side of the transfer ball 20 into contact with the writing surface, the leading edge of the tip body 10' is to be avoided. It is set so that it becomes difficult to touch the writing surface, the friction between the writing surface and the front edge of the tip body 10' is reduced, so that smooth writing can be performed.

A plurality of bending restraining projections 15 are provided around the reduced portion 61a at predetermined intervals in the circumferential direction. A portion between the curvature suppressing projections 15 adjacent in the circumferential direction is an ink guide groove 15b continuous in the front-rear direction.

Each of the bending restraining projections 15 is reduced in diameter in a stepped shape with respect to the inner diameter of the constricted portion 12 .

The position of the front end surface 15a of the bending suppression protrusion 15 is, as shown by the double-dotted chain line in FIG. 20, the transfer ball 20 is retracted by the pressing force from the front, 12b) (specifically, the corner portion), between the rear side portion of the retracted transfer ball 20 and the front end surface 15a of the deflection suppression protrusion 15, the ink storage space s3 ) is set appropriately to ensure

And, as shown in FIG. 20, each bending restraining projection 15 has a front end surface 15a that inclines backward as it approaches the center, and a rear end surface 15c that inclines forward as it approaches the center. , the protruding end surface 15d protruding in the radially inward direction is in proximity to or in contact with the outer peripheral surface of the reduced portion 61a.

The protruding end face 15d is dimensioned to be close to the outer circumferential surface of the reduced portion 61a without contacting it. In some cases.

In addition, a plurality of ink guide grooves 15b are arranged at predetermined intervals in the circumferential direction on the inner peripheral side of the curvature suppressing protrusion 15 and the constriction 12 . Each of the ink guide grooves 15b is continuous in the front-rear direction so as to penetrate the curvature suppressing protrusion 15 and the constriction 12 . Each of the ink guide grooves 15b has its bottom (inner surface in the outer diameter direction) positioned on the radially outward side from the inner diameter of the constricted portion 12 (refer to Fig. 19).

The ink guide groove 15b causes the ink on the rear side of the curvature restraining projection 15 to flow toward the front side of the curvature restraining projection 15 and the constriction 12 .

Therefore, according to the ballpoint pen tip 5, as shown in Figs. 20 to 21, in the initial state, the transfer ball 20 is moved forward from the constriction 12, and the rear end of the transfer ball 20 is reduced. It is close to or in contact with the front end of the portion 61a.

In this state, a relatively strong pressing force in the rear direction is applied to the transfer ball 20, and when the reduced portion 61a is inclined to bend in the radial direction by the pressing force, the outer peripheral surface of the reduced portion 61a suppresses bending. It is accommodated by the inner peripheral surface of the projection 15, and the curvature is suppressed.

Accordingly, the constricted portion 61a hardly bends in the radial direction and is elastically contracted backward. Accordingly, it is possible to prevent ink breakage or line width from becoming unstable in writing in a specific direction due to the warpage.

That is, it is possible to prevent the ink flow rate from being unstable due to the non-uniform gap between the protruding end face 15d and the reduced portion 61a due to the warping, and the problem caused by such a phenomenon can be solved.

Further, according to a preferred example of this embodiment, the ink guide groove 15b spanning the curvature restraining projection 15 and the constriction 12 is provided, and the ink storage space s3 is provided in front of the front end surface 15a. Since the ink flow rate can be secured stably, in particular, even when the transfer ball 20 is relatively largely retracted due to strong pen pressure being applied, the flow path and storage space of the ink do not disappear, and the You can write thick lines.

In addition, as shown by the double-dotted chain line in Fig. 20, even when the amount of retraction of the transfer ball 20 is relatively large due to the strong pressing force, the transfer ball 20 is accommodated by the constriction 12 and is retracted. Since the front end side of the transfer ball 20 of can do.

<Other Modifications>

In addition, in the above embodiment, the positional relationship between the ink guide groove 12a of the constricted portion 12 (see Fig. 5) and the inner corner portion 11c of the square cylindrical inner wall surface 11b is not particularly limited, As an aspect of further reducing the flow resistance of ink, a plurality of ink guide grooves 12a may be arranged so as to correspond to the inner corner-shaped portions 11c, respectively.

Further, in the ballpoint pen tip 2 shown in Fig. 9, a gap s2 is provided between the front end of the receiving member 30 and the rear end of the transfer ball 20, but as another example, the gap s2 is omitted and receiving It is also possible to make the front end of the member 30 into the aspect which made contact with the rear end of the transfer ball 20. As shown in FIG.

In the illustrated example, as a particularly preferable aspect, a rectangular cylindrical inner wall surface 11b (see FIG. 3 ) is provided in the ball house 11. As another example, instead of the rectangular cylindrical inner wall surface 11b, a cylindrical inner wall surface, etc. , it is also possible to set it as an aspect in which an inner wall surface of a shape other than that shown is provided. By advancing and retreating, a written line having a line width corresponding to the pressing force can be obtained.

Moreover, according to the example of illustration, with respect to the ball-point pen tip 1 (2, 3 or 4) which made line width adjustment possible by the accommodation member 30 etc., the rectangular cylindrical inner wall surface 11b in the ball house 11 (FIG. 3) reference), the prismatic inner wall surface 11b has a ballpoint pen tip not provided with the accommodating member 30 (50 or 60), or instead of the accommodating member 30 (50 or 60), a transfer ball 20 ) can be applied to the inner wall surface of the ball house with respect to a ballpoint pen tip or the like having a coil spring that rebounds. By the gap s1 of , a stable ink flow rate can be ensured.

Further, according to the above ballpoint pen tip (1) (2, 3 or 4), as a particularly preferred embodiment, the receiving member 30 (50 or 60) is formed of a hard synthetic resin material that can be elastically deformed. As another example, the receiving member (30) It is also possible to form part or all of (50 or 60) of a metal material (as a specific example, stainless steel, brass, etc.). In this case, it is preferable to form the transfer ball 20 from a synthetic resin material that can be elastically deformed.

Further, according to the illustrated example, a single color ballpoint pen is configured as an example of the writing instrument 100 provided with the ballpoint pen tip 1 . As another example of the writing instrument 100 , a multicolor writing instrument provided with refills of plural colors of ballpoint pens, ballpoint pens It is also possible to constitute a multifunctional writing instrument having a plurality of types of refills, such as refills and mechanical pencil refills. It goes without saying that the writing instrument 100 can be configured similarly for the ballpoint pen tips 2, 3, or 4 as well.

Note that, in the ballpoint pen tip 3 (see Fig. 10), separate front member 51 and rear member 52 are brought into contact with each other, but as another example, front member 51 and rear member 52 are It is also possible to set it as the aspect which integrated by fitting or screwing, the aspect which integrated the front side member 51 and the rear side member 52 by double molding, etc.

Further, in the ballpoint pen tip 4 (see Fig. 15), the front member 61 and the rear member 62 are integrally connected. As another example, a recess is provided at the front end of the rear member 62, and the recess is formed in the recess. It is also possible to make the front side member 61 into the aspect which fitted so that advancing and retreating was possible.

In addition, according to the illustrated example, although the coil spring 40 is provided only for the ballpoint pen tip 2, it is better to provide the coil spring 40 by applying approximately the same structure to the ballpoint pen tip 3 and the ballpoint pen tip 4 as well. possible.

Further, in the ballpoint pen tips 1 and 4 (see Figs. 1 and 15), the receiving member 30 or 60 was fitted so as not to advance and retreat with respect to the tip body 10, as another example, the receiving member 30 or 60 It is also possible to make it into a mode in which it engages with respect to the tip body 10 so that it cannot retract and can advance. In this case, the forward movement of the receiving member 30 or 60 is regulated by contact with the transfer ball 20 .

Further, in the ballpoint pen tip 5 ( FIGS. 18 to 21 ), the bending restraining projection 15 was dimensioned so as not to contact the side wall of the reduced portion 61a and approached. As another example, the bending restraining projection 15 is It is also possible to set the dimensions so as to be in contact with the side wall of the reduced portion 61a, and to contract the reduced portion 61a by contacting the curvature suppression protrusion 15 by a backward pressing force.

Further, the ballpoint pen tip 5 ( FIGS. 18 to 21 ) has a configuration in which a bending restraining projection 15 is added to the ballpoint pen tip 4 (see FIG. 15 ). As another example, the ballpoint pen tip 1 ( FIG. 15 ) 1), with respect to the ballpoint pen tip 2 (FIG. 9) or the ballpoint pen tip 3 (FIG. 10), it is also possible to add the bending restraining projection 15.

In addition, this invention is not limited to embodiment mentioned above, It can change suitably in the range which does not change the summary of this invention.

1, 2, 3, 4, 5: Ballpoint pen tip
10, 10': tip body
11: Ball House
11a: cylindrical inner circumferential surface
11a1: inner annular projection
11b: square cylindrical inner wall surface
12: constriction
15: bending restraint projection
15a: shear plane
15b: ink guide groove
15c: rear end
15d: Extruded section
20: Warrior Ball
30, 50, 60: receiving member
31, 51a, 61a: reduced portion
32, 52b, 62a: support projections
51, 61: front member
52, 62: rear member
100: writing instrument (ballpoint pen)
120: ballpoint pen refill
s1, s2: gap
s3: ink storage space

Claims (11)

A tubular tip body penetrating the inside in the front-rear direction, and a transfer ball accommodated in a front end inside the tip body and projecting an outer circumferential front end forward from the tip body; A ballpoint pen tip comprising a receiving member disposed on the rear side of the transfer ball in the tip body, the latter part of the transfer ball being accommodated by the front end of the receiving member,
The accommodating member has, on its front end side, a reduced section whose cross-sectional area is gradually reduced toward the front, and the front end of the reduced section is disposed behind the transfer ball, and is rearward ( The rear portion is fixed to the tip body so as not to be retracted, and is configured to elastically contract when a pressing force is received from the transfer ball,
The inner wall (內壁) of the tip body is provided with a bending restraining protrusion for suppressing the curvature of the reduced portion by proximity or contact with the side wall of the reduced portion,
The accommodating member has a plurality of support protrusions protruding in a radial outward direction at a rear side of the reduced portion at intervals in the circumferential direction, and these support protrusions are press-contacted to the inner wall surface of the tip body to prevent retraction. firmly fixed,
the accommodating member is configured in a bar shape from two members, a front member having the reduced portion and a rear member having the support protrusion,
wherein the rear member is formed of a material having a higher wear resistance than that of the front member;
ballpoint pen tip. According to claim 1,
A ballpoint pen tip, wherein a plurality of the bending restraining projections are provided at intervals in the circumferential direction, and an ink guide groove communicating in the front-rear direction between the bending restraining projections adjacent in the circumferential direction. According to claim 1,
A constriction portion for receiving the transfer ball when retracted by a front end surface is provided on the front end side of the tip body, and the bending restraining projection is disposed on a rear side of the front end surface of the constriction portion. 4. The method of claim 3,
The ballpoint pen tip, wherein the front and rear positions of the constricted portion are set so as to project the received transfer ball forward from the front end of the tip body. According to claim 1,
The ballpoint pen tip, wherein the front member is formed of a material that is elastically deformable more easily than that of the rear member. According to claim 1,
The ballpoint pen tip, wherein the front member is provided between the transfer ball and the rear member in a state in which the front member is loosely fitted to the inner circumferential surface of the tip body. According to claim 1,
In the front member, a plurality of vertical ribs extending in the front-rear direction are provided on the outer periphery of the front-side member at intervals in the circumferential direction, and the number of these vertical ribs and the number of the supporting protrusions are different. tip. According to claim 1,
A ballpoint pen tip in which the front member and the rear member are connected and integrated. A cylindrical tip body penetrating the inside in the front-rear direction, and a transfer ball accommodated in a front end side in the tip body and projecting an outer peripheral front end side forward from the tip body; A ballpoint pen tip comprising a receiving member disposed on the rear side of the transfer ball in the tip body, the latter part of the transfer ball being accommodated by the front end of the receiving member,
The accommodating member has, on its front end side, a reduced portion whose cross-sectional area is gradually reduced toward the front, and the frontmost end of the reduced portion is disposed behind the transfer ball, and is further rearward than the reduced portion ( The rear portion is fixed to the tip body so as not to be retracted, and is configured to elastically contract when a pressing force is received from the transfer ball,
The inner wall (內壁) of the tip body is provided with a bending restraining protrusion for suppressing the curvature of the reduced portion by proximity or contact with the side wall of the reduced portion,
The accommodating member has a plurality of support protrusions protruding in a radial outward direction at a rear side of the reduced portion at intervals in the circumferential direction, and the support protrusions are pressed into contact with the inner wall surface of the tip body to prevent retraction. firmly fixed,
the accommodating member is configured in a bar shape from two members, a front member having the reduced portion and a rear member having the support protrusion,
wherein the front member is formed of a material that is elastically deformable more easily than that of the rear member;
ballpoint pen tip. A tubular tip body penetrating the inside in the front-rear direction, and a transfer ball accommodated in a front end inside the tip body and projecting an outer circumferential front end forward from the tip body; A ballpoint pen tip comprising a receiving member disposed on the rear side of the transfer ball in the tip body, the latter part of the transfer ball being accommodated by the front end of the receiving member,
The accommodating member has, on its front end side, a reduced portion whose cross-sectional area is gradually reduced toward the front, and the frontmost end of the reduced portion is disposed behind the transfer ball, and is further rearward than the reduced portion ( The rear portion is fixed to the tip body so as not to be retracted, and is configured to elastically contract when a pressing force is received from the transfer ball,
The inner wall (內壁) of the tip body is provided with a bending restraining protrusion for suppressing the curvature of the reduced portion by proximity or contact with the side wall of the reduced portion,
The accommodating member has a plurality of support protrusions protruding in a radial outward direction at a rear side of the reduced portion at intervals in the circumferential direction, and the support protrusions are pressed into contact with the inner wall surface of the tip body to prevent retraction. firmly fixed,
the accommodating member is constituted by two members, a front member having the reduced portion and a rear member having the support protrusion,
In the front member, a plurality of vertical ribs extending in the front-rear direction are provided on the outer periphery of the rear side of the reduced portion at intervals in the circumferential direction, and the number of the vertical ribs and the number of the supporting protrusions are different,
ballpoint pen tip. A writing instrument comprising the ballpoint pen tip according to any one of claims 1 to 10.

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