JP6637659B2 - Ballpoint pen tip and writing implement equipped with the ballpoint pen tip - Google Patents

Description

  The present invention relates to a ballpoint pen tip that changes the width of a writing line, and a writing instrument equipped with the ballpoint pen tip.

2. Description of the Related Art Conventionally, as a writing instrument of this type, for example, there is a writing instrument in which the relative position of a rod extending member (9) that receives a ball (2) from the rear side is adjusted, as described in Patent Document 1. According to this writing instrument, if the relative position of the rod-extending member (9) is changed by adjusting the amount of screwing of the tip (T) or the rod-extending member (9) or the amount of rotation of the movement control member (20), the ball (2) can be obtained. ) And the gap between the fore edge (4a) of the tip (T) changes, so that the ink discharge amount also changes, and as a result, the width of the writing line also changes.
Further, as another conventional technique, there is one in which a line width is changed by adjusting an inclination angle of a tip with respect to a writing surface (see Patent Document 2).

  However, in the related art of Patent Literature 1, it is necessary to adjust the relative position of the rod extending member (9) in order to change the width of the writing line, and the adjustment operation is troublesome. Further, in the related art of Patent Literature 2, there is a case where the writing posture is lost due to a change in the inclination angle of the writing implement.

JP-A-2004-1246 JP 2013-252654 A

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional circumstances, and an object thereof is to provide a ballpoint pen tip capable of easily changing a writing line width, and a writing implement having the ballpoint pen tip.

One means for solving the above problem is a substantially cylindrical chip body penetrating the inside in the front-rear direction, and a front end side of the outer peripheral surface which is housed at a front end side in the chip body and projects forward from the chip body. A transfer ball, and a rod-shaped receiving member disposed rearward of the transfer ball in the chip main body. The front half of the transfer ball is positioned on the inwardly directed annular projection on the front end side in the chip main body from the rear side. with contacting part side, the latter half portion of the transfer ball, said a ballpoint pen tip which is adapted to receive the front end of the rod-shaped receiving member without being in the inner surface of the tip body, the rod-shaped receiving member, its At the front end of the transfer ball, the front end of the reduced portion is disposed behind the transfer ball, and a portion behind the reduced portion. The result advance and retreat incapable fixed to the tip body is configured to contract elastically by the pressing force received from the transfer ball, the rod-shaped receiving member, the rearward of the reduction unit, intervals in the circumferential direction And a plurality of support projections projecting in the radially outward direction, and these support projections are fixed to the inner wall surface of the chip body by pressing so as to be unable to advance and retreat .

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

It is a longitudinal section showing an example of a ball-point pen tip concerning the present invention. 4A and 4B show an example of a rod-shaped receiving member, where FIG. 4A is a view from the front, FIG. 4B is a half-sectional view, and FIG. It is sectional drawing which follows the (III)-(III) line in FIG. It is a principal part longitudinal cross-sectional view of the chip main body in the state where the front-end | tip part was not crimped. It is the figure which looked at the chip main body in the state where the tip was not crimped from the front side. It is a perspective view which shows the principal part longitudinal cross section of the chip main body in the state where the front-end | tip part was not crimped. It is a longitudinal section of the writing implement provided with the ball-point pen tip concerning the present invention. It is principal part sectional drawing which shows the use condition of the writing implement. It is a longitudinal section showing other examples of a ball-point pen tip concerning the present invention.

The first feature of the present embodiment is that a substantially cylindrical chip main body penetrating the inside in the front-rear direction, and a front end side of the outer peripheral surface which is housed at a front end side in the chip main body and protrudes forward from the chip main body. A transfer ball, and a rod-shaped receiving member disposed rearward of the transfer ball in the chip main body. The front half of the transfer ball is positioned on the inwardly directed annular projection on the front end side in the chip main body from the rear side. A ball-point pen tip that is brought into contact with the rear side of the transfer ball, and is not received by the inner surface of the chip body but by the front end of the rod-shaped receiving member. On the front end side, there is a reduced portion whose cross-sectional area is gradually reduced toward the front, and the foremost end of the reduced portion is arranged behind the transfer ball, and a portion behind the reduced portion is removed. Previous Will advance and retreat impossible secured to the chip body, elastically contracts by the pressing force received from the transfer ball.
According to the above configuration, the front end side of the rod-shaped receiving member is prevented from bending in the radial direction by the reduced portion, and a writing line having a thickness corresponding to the pressing force can be stably obtained.

  As a second feature, in order to stabilize the flow amount of ink, a square cylindrical inner wall surface is formed on the front end side in the chip body, and this square cylindrical inner wall surface is formed on the outer peripheral surface of the transfer ball. It was made to approach or contact.

  As a third feature, in order to more effectively suppress that the front end side of the rod-shaped receiving member bends in the radial direction, the reduced portion continuously extends the outer diameter rearward from the contact surface with the transfer ball. It is formed in the shape of a truncated cone that is enlarged in size.

  As a fourth feature, in order to ensure a sufficient ink flow path in the chip body and to achieve a favorable aspect of manufacturability, the rod-shaped receiving member is provided with a circumferential interval behind the reduced portion. It has a plurality of support projections that protrude outward in the radial direction, and these support projections are pressed against the inner wall surface of the chip body to be fixed so that they cannot advance or retreat.

  As a fifth feature, the rod-shaped receiving member is formed of a synthetic resin material so that a soft brush feeling can be obtained.

  A sixth feature is that a coil spring is annularly arranged around the rod-shaped receiving member, and a front end of the coil spring is brought into contact with the transfer ball, and a rear end of the coil spring is supported irreversibly. did.

  As a seventh feature, a writing implement was configured with the ballpoint pen tip.

Next, a preferred embodiment having the above features will be described in detail with reference to the drawings.
In this specification, “forward” means the tip direction of the ballpoint pen tip, and “rear” means the opposite direction. The “radial direction” means a direction away from the center in the radial direction of the ballpoint pen tip, and the “radial direction” means the opposite direction.

FIG. 1 shows a ballpoint pen tip 1 according to the present invention.
The ballpoint pen tip 1 has a substantially cylindrical chip main body 10 penetrating the inside in the front-rear direction, and is housed at a front end side in the chip main body 10 and has a front end side of an outer peripheral surface projected forward from a front end of the chip main body 10. The chip includes a transfer ball 20 and a rod-shaped receiving member 30 disposed rearward of the transfer ball 20 in the chip body 10.
The ball-point pen tip 1 abuts the front half of the transfer ball 20 from the rear side on the inward annular projection 11a1 on the front end side of the chip body 10 and the rear half of the transfer ball 20 with the chip body 10 Is received by the front end of the rod-shaped receiving member 30 without receiving it on the inner surface.
Further, in the ball-point pen chip 1, the inner wall surface on the front end side of the chip body 10 is formed in a rectangular cylindrical shape, and the outer peripheral surface of the transfer ball 20 is brought close to or in contact with the rectangular cylindrical inner wall surface 11b.

The chip main body 10 is formed of an alloy such as stainless steel, brass, or nickel silver, or a synthetic resin into a substantially cylindrical shape having a tapered conical portion on the tip end side.
In the chip body 10, a ball house 11, a constricted portion 12, a constricted hole 13, and a large-diameter hole 14 are provided in this order from the front end side, and these internal spaces communicate with each other in the front-rear direction.

  The ball house 11 allows the transfer ball 20 to rotate freely by an inward annular projection 11a1 near the frontmost end, a rectangular cylindrical inner wall surface 11b extending rearward from the inward annular projection 11a1, and a front end surface of the constricted portion 12. It constitutes a space to accommodate.

The inward annular projection 11a1 is formed by caulking the front end of the chip body 10 from the outside after the transfer ball 20 is inserted into the ball house 11.
That is, in a stage before the transfer ball 20 is inserted, a cylindrical inner peripheral surface 11a is formed near the forefront end of the ball house 11, as shown in FIG. 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, so that an inward annular protrusion 11a1 is formed on the front end side of the cylindrical inner peripheral surface 11a. The inward annular projection 11a1 contacts the front half of the transfer ball 20 so as to protrude radially inward from the cylindrical inner peripheral surface 11a.

  The rectangular cylindrical inner wall surface 11b is a regular polygonal cylindrical (in the illustrated example, a regular nine-sided cylindrical) inner wall surface. Each surface constituting the rectangular cylindrical inner wall surface 11b is formed as a flat surface. And, of the plurality of surfaces constituting the rectangular cylindrical inner wall surface 11b, between the adjacent surfaces in the circumferential direction, a corner-shaped portion 11c is formed.

In addition, the constricted portion 12 has a substantially constricted shape (or a radially inward direction) by reducing a portion behind the rectangular cylindrical inner wall surface 11b to an inner diameter smaller than the minimum diameter of the rectangular cylindrical inner wall surface 11b. It is a portion formed in a protruding annular projection shape (see FIGS. 1 and 4). The inner peripheral surface of the hole passing through the constricted portion 12 is a substantially cylindrical surface, and an ink guide groove 12a (see FIG. 5) penetrating in the front-rear direction is formed on this surface. The flow cross-sectional area of the ink guide groove 12a is set so as to appropriately secure the ink flow amount.
In addition, as an example other than the illustrated example, it is also possible to omit the constricted portion 12 and to connect the rectangular cylindrical inner wall surface 11b to the front end side of the tapered hole 13.
A tapered hole 13 is provided on the rear side of the constricted portion 12.

  The tapered hole 13 is a substantially truncated conical hole whose diameter is continuously reduced toward the front. The tapered hole 13 accommodates a reduced portion 31 of a rod-shaped receiving member 30 to be described later, and forms the reduced space 31 into a surrounding space. Is an ink distribution channel. The large diameter hole 14 is continuous with the rear end side of the tapered hole 13.

The large-diameter hole 14 is formed in a substantially cylindrical shape that continues rearward from the rear end of the tapered hole 13. The rod-shaped receiving member 30 is inserted into the large-diameter hole 14, and a plurality of support protrusions 32 on the rear side of the rod-shaped receiving member 30 are fixed to the inner wall surface of the large-diameter hole 14 by pressing.
The large-diameter hole 14 is formed by using a plurality of drills whose diameters are reduced stepwise to form holes whose diameter is reduced stepwise toward the front, and then continuous in the front-rear direction by finishing such as reamer processing. Processed into holes of the same diameter. As an example other than the illustrated example, the finishing process may be omitted, and the large-diameter hole 14 may be a hole whose diameter is reduced stepwise toward the front.

The transfer ball 20 is formed in a spherical shape from a hard metal material such as a sintered body mainly containing tungsten carbide or silicon carbide, or a synthetic resin material, and is accommodated in the ball house 11.
The front half of the transfer ball 20 is pressed against an inward annular protrusion 11 a 1 on the front end side of the ball house 11. The rear half of the transfer ball 20 is received only by the front end surface of the rod-shaped receiving member 30 without being received by the front end surface of the constricted portion 12 which is the inner surface of the chip body 10. That is, a gap is secured between the front end surface of the constricted portion 12 and the rear half portion of the transfer ball 20 (see FIG. 1), and the front end surface of the rod-shaped receiving member 30 contacts the rear end surface of the transfer ball 20. I have.
The outer diameter of the transfer ball 20 is set to be slightly smaller than that of a virtual sphere in contact with the rectangular cylindrical inner wall surface 11b of the ball house 11. Therefore, the outer peripheral surface of the transfer ball 20 is close to the respective surfaces constituting the rectangular cylindrical inner wall surface 11b (see FIG. 3).
Note that the transfer ball 20 may be slightly eccentric with respect to the center of the chip body 10 due to a variation in dimensional accuracy of the inner surface of the ball house 11 or the like. May come into contact with the surface constituting the inner wall surface 11b.
As shown in FIG. 3, a corner 11c is formed between the adjacent flat surfaces of the rectangular cylindrical inner wall surface 11b around the transfer ball 20. The inside corner portion 11c secures a gap s1 serving as an ink circulation path.

Further, the rod-shaped receiving member 30 has, at its front end side, a reduced portion 31 whose cross-sectional area is gradually reduced toward the front, and the foremost end of the reduced portion 31 is arranged behind the transfer ball 20. I have. The rod-shaped receiving member 30 has a plurality of (three in the illustrated example) support projections 32 projecting outward in the circumferential direction at intervals in the circumferential direction behind the reduced portion 31. The protrusion 32 is pressed against the inner wall surface of the chip body 10 to be fixed so as not to advance and retreat.
The rod-shaped receiving member 30 is formed of an elastically deformable hard synthetic resin material such as POM (polyacetal), PE (polyethylene), PP (polypropylene), and contracts elastically by a pressing force received from the transfer ball 20.

  The reduced portion 31 is formed in a truncated cone shape whose outer diameter is continuously increased rearward from a contact surface with the transfer ball 20.

As shown in FIG. 2, a plurality of (three in the illustrated example) support projections 32 are provided to protrude substantially radially. The plurality of support projections 32 are pressed against the inner peripheral surface of the chip main body 10 when the rod-shaped receiving member 30 is inserted into the chip main body 10 from the rear side of the chip main body 10 in the manufacturing stage of the ballpoint pen tip 1. You.
In FIG. 2, reference numeral 32 a denotes a tapered surface that facilitates the insertion operation, and each tapered surface 32 a is formed on the front end side of each support protrusion 32.
The space between the support projections 32 adjacent in the circumferential direction functions as an ink flow path.

Next, a writing instrument 100 using the ballpoint pen tip 1 having the above configuration will be described (see FIG. 7).
The writing implement 100 causes the ball-point pen tip 1 at the front end of the ball-point pen refill 120 to protrude from the front end of the barrel 110 by pressing the knock portion 140, and releases this protruding state by bending the clip 111 toward the center of the barrel. It is an infested ballpoint pen.
The ball-point pen refill 120 is formed by connecting the ball-point pen tip 1 to the front end of the ink storage tube 121 and filling the inside thereof with ink.

Next, an operation effect at the time of writing with the ballpoint pen tip 1 and the writing implement 100 (ballpoint pen) having the above-described 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 a writing surface, the rod-shaped receiving member 30 elastically contracts in the axial direction, The transfer ball 20 retreats slightly. Therefore, a gap is formed between the transfer ball 20 and the inward annular protrusion 11a1, and ink is ejected from the gap. When the pressing force is reduced, the rod-shaped receiving member 30 is restored to the original length, the transfer ball 20 advances, and the gap is narrowed.

Therefore, when the pressing force is relatively large, the amount of contraction of the rod-shaped receiving member 30 and the amount of retreat of the transfer ball 20 increase, and the gap between the transfer ball 20 and the inward annular protrusion 11a1 increases. The amount increases and the writing line becomes thicker.
Further, when the pressing force is relatively small, the amount of contraction of the rod-shaped receiving member 30 and the amount of retreat of the transfer ball 20 become small, and the gap between the transfer ball 20 and the inward annular projection 11a1 becomes narrow. The amount is reduced and the writing line becomes thinner.

When writing is performed in a normal writing posture, due to a writing angle or the like at the time of writing, the front end side of the rod-shaped receiving member 30 has a direction inclined with respect to the direction of the center line of the rod-shaped receiving member 30. In some cases, a pressing force is applied (see FIG. 8).
According to the ball-point pen tip 1 of this embodiment, since the bar-shaped receiving member 30 has the reducing portion 31 that gradually reduces the cross-sectional area toward the front at the front end side, it receives the pressing force in the inclined direction as described above. Even in this case, the front end side of the rod-shaped receiving member 30 does not easily bend in the radial direction and elastically contracts in the axial direction.
That is, if the front end side of the rod-shaped receiving member 30 is formed in a straight rod shape, the front end side portion is bent in the radial direction, deviates from the center of the transfer ball 20, and the retreat amount of the transfer ball 20 is unstable. And the ink ejection amount and the thickness of the writing line may become unstable. According to the present invention, such a phenomenon is prevented, and a writing line having a thickness corresponding to the pressing force is stably obtained. be able to.

In addition, a gap s1 is secured around the transfer ball 20 by the corner portion 11c of the rectangular cylindrical inner wall surface 11b, so that the gap s1 serves as an ink flow path and stably maintains the ink flow rate. .
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 a cylindrical surface is used. In comparison, 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.
Note that the ballpoint pen tip shown below is a partially modified version of the ballpoint pen tip 1 described above. Therefore, the changed portion will be mainly described in detail, and redundant detailed description will be omitted.

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, in the ball-point pen tip 2, the coil spring 40 is annularly arranged around the reduced portion 31 of the rod-shaped receiving member 30, and the front end of the coil spring 40 is brought into contact with the transfer ball 20. The rear end of the coil spring 40 is supported by the step on the rear end side of the reduced portion 31 so as not to retreat, and a gap s2 is secured between the rear end of the transfer ball 20 and the front end of the reduced portion 31.

According to the ball-point pen tip 2 having the above-described configuration, when the transfer ball 20 is not used with no backward pressing force, the transfer ball 20 is pressed against the inward annular protrusion 11a1 by the resilient force of the coil spring 40, and the transfer is performed. Ink leakage from between the ball 20 and the inward annular protrusion 11a1 can be effectively prevented.
Further, when the transfer ball 20 is pressed against the surface to be written, the transfer ball 20 slightly retreats, so that a gap is formed between the transfer ball 20 and the inward annular projection 11a1, and ink is ejected from the gap.
When the pressing force on the transfer ball 20 is relatively large, the rear end surface of the transfer ball 20 comes into contact with the front end surface of the rod-shaped receiving member 30 and the rod-shaped receiving member 30 is elastically contracted. The gap between the orientation annular protrusion 11a1 is increased, the ink flow rate is increased by the gap, and the writing line becomes thicker. When the transfer ball 20 is formed of a synthetic resin material, the transfer ball 20 is easily contracted in addition to the contraction of the rod-shaped receiving member 30, so that the ink flow rate can be further increased.
Therefore, in the ball-point pen tip 2 as well, similarly to the ball-point pen tip 1, a writing line having a thickness corresponding to the pressing force can be stably obtained.
The ballpoint pen tip 2 can be used as a component of the writing instrument 100 (ballpoint pen), similarly to the ballpoint pen tip 1 described above.

  In the above embodiment, the positional relationship between the ink guide groove 12a of the constricted portion 12 and the corner-shaped portion 11c of the rectangular inner wall surface 11b is not particularly limited. The plurality of ink guide grooves 12a may be arranged so as to correspond to the corner portions 11c.

  In the ball-point pen tip 2 shown in FIG. 9, the gap s2 is provided between the front end of the rod-shaped receiving member 30 and the rear end of the transfer ball 20, but as another example, the gap s2 is omitted and the rod-shaped receiving member 30 is omitted. The front end of the transfer ball 20 may be in contact with the rear end of the transfer ball 20.

  Also, in the illustrated example, as a particularly preferred embodiment, the square cylindrical inner wall surface 11b is provided in the ball house 11, but as another example, a cylindrical inner wall surface instead of the square cylindrical inner wall surface 11b may be used. It is also possible to adopt a mode in which an inner wall surface having a shape is provided. In this other example, the rod-shaped receiving member 30 is expanded and contracted by the pressing force from the front, and the transfer ball 20 is advanced and retracted. A writing line having a line width can be obtained.

  Further, according to the illustrated example, the rectangular cylindrical inner wall surface 11b is provided in the ball house 11 for the ball-point pen tip 1 whose line width can be adjusted by the rod-shaped receiving member 30 or the like. It is possible to apply the ball-point pen tip not having the rod-shaped receiving member 30 or the ball-point pen tip having a coil spring for repelling the transfer ball 20 in place of the rod-shaped receiving member 30 to the inner wall surface of the ball house. Also in this case, a stable ink flow rate can be ensured by the gap s1 inside the corner-shaped portion 11c in the rectangular cylindrical inner wall surface 11b.

  Further, according to the above embodiment, the rod-shaped receiving member 30 is formed of a hard synthetic resin material that can be elastically deformed. However, as another example, the rod-shaped receiving member 30 is formed of a metal material (specifically, stainless steel, brass, or the like). It is also possible to form from. In such a case, it is preferable that the transfer ball 20 be formed of an elastically deformable synthetic resin material.

  In addition, according to the illustrated example, a single-color ballpoint pen is configured as an example of the writing implement 100 including the ballpoint pen tip 1. However, as another example of the writing implement 100, a multicolor writing implement including a plurality of ballpoint pen refills, It is also possible to configure a multifunctional writing instrument provided with a plurality of types of refills such as a pencil and a refill.

1: Ballpoint pen tip 10: Tip body 11: Ball house 11a: Cylindrical inner peripheral surface 11a1: Inwardly annular projection 11b: Square cylindrical inner wall surface 12: Narrow portion 20: Transfer ball 30: Rod-shaped receiving member 31: Reduction portion 32 : Support projection 100: Writing instrument (ballpoint pen)
120: ballpoint pen refill s1, s2: gap

Claims (5)

A substantially cylindrical chip main body penetrating the inside in the front-rear direction, a transfer ball housed at a front end side in the chip main body, and a front end side of an outer peripheral surface protruding forward from the chip main body; A rod-shaped receiving member disposed on the rear side of the transfer ball,
The front half of the transfer ball is brought into contact with the inward annular protrusion on the front end side of the chip body from the rear side thereof, and the second half of the transfer ball is not received on the inner surface of the chip body. A ballpoint pen tip adapted to be received by the front end of the member,
The rod-shaped receiving member, the front end of its having a reduction unit which is reduced gradually cross-sectional area toward the front, along with arranging the foremost end portion of the fused small portions to the rear of the transfer ball, the fused small The portion behind the portion is fixed to the chip body so as not to advance and retreat, and is configured to elastically contract by a pressing force received from the transfer ball,
The rod-shaped receiving member has a plurality of support protrusions projecting radially outward, spaced apart in the circumferential direction, behind the reduced portion, and pressing these support protrusions against the inner wall surface of the chip body. A ball-point pen tip, which is fixed so that it cannot advance or retreat . A substantially cylindrical chip main body penetrating the inside in the front-rear direction, a transfer ball housed at a front end side in the chip main body, and a front end side of an outer peripheral surface protruding forward from the chip main body; A rod-shaped receiving member disposed on the rear side of the transfer ball,
The front half of the transfer ball is brought into contact with the inward annular protrusion on the front end side of the chip body from the rear side thereof, and the second half of the transfer ball is not received on the inner surface of the chip body. A ballpoint pen tip adapted to be received by the front end of the member,
The rod-shaped receiving member has, at its front end, a reduced portion having a gradually reduced cross-sectional area toward the front, and arranges the foremost end of the reduced portion behind the transfer ball, and A portion on the rear side is fixed to the chip body so as not to advance and retreat, and is configured to elastically contract by a pressing force received from the transfer ball,
The rod-shaped receiving member has a coil spring disposed annularly around the periphery thereof, the front end of the coil spring abutting on the transfer ball, and the rear end of the coil spring is irreversibly supported. Characteristic ballpoint pen tip. 3. The ballpoint pen tip according to claim 1, wherein the rod-shaped receiving member is formed of a hard synthetic resin material that can be elastically deformed . 4. A space as an ink flow passage communicating from the rear side of the rod-shaped receiving member to the transfer ball from the rear side of the rod-shaped receiving member, is secured outside the rod-shaped receiving member. of the ballpoint pen tip. A writing implement comprising the ballpoint pen tip according to claim 1.

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