JP7680295B2 - writing implements - Google Patents

Description

The present invention relates to a writing instrument that houses a writing lead with a writing part at the front end inside a barrel.

2. Description of the Related Art Conventionally, this type of writing instrument includes a writing instrument, such as a marker pen, ballpoint pen, or mechanical pencil, in which the writing lead protrudes from and retracts from the front end of a barrel, as described in, for example, Japanese Patent Application Laid-Open No. 2003-233696.
In this writing implement, the shaft-shaped portion at the front end of the slide piece is inserted and fitted into a cylindrical mounting hole in a tail plug provided at the rear end of the writing core.

JP 2020-179623 A

In such conventional writing implements, although the mounting hole is fitted to the sliding piece, the writing lead may rotate relative to the sliding piece due to force or vibration applied to the writing lead. In such cases, the following inconveniences may occur.
For example, if the writing part of the writing lead is a writing lead for a marker pen and has an inclined surface at its tip, when the writing lead rotates, the contact between the inclined surface and the surface being written on becomes unstable, and the writer may not be able to draw a line of the intended thickness.
Furthermore, if the writing lead is for a mechanical pencil, if the tip of the lead wears unevenly and the writing line becomes thick, even if you try to eliminate the uneven wear by rotating the barrel, the writing lead will rotate relative to the barrel, and it may not be possible to eliminate the uneven wear.

In view of the above problems, the present invention has the following configuration.
A writing instrument comprising a barrel, a base member provided at the rear side within the barrel, and a writing lead removably connected to the front end side of the base member with a writing portion facing forward, one of the base member and the writing lead having a mating recess and the other having a mating protrusion that fits into the mating recess, and a rotation regulating portion that prevents the writing lead from rotating in a circumferential direction relative to the base member , the rotation regulating portion being composed of a small recess formed by recessing a portion of the peripheral wall of the mating recess in the circumferential direction, and a small protrusion provided on the outer periphery of the mating protrusion that fits into the small recess .

The present invention is configured as described above, so the writing lead can be held so that it does not rotate.

1 is a vertical cross-sectional view showing an example of a writing instrument according to the present invention. FIG. 2 is a cross-sectional view taken along line (II)-(II) in FIG. FIG. 2 is a vertical cross-sectional view showing a connection state between the writing lead and the base member. FIG. 2 is a perspective view illustrating an example of a base member. 1 is an exploded view of a writing lead and a base member, showing a longitudinal section of the writing lead and a side view of the base member. FIG. 2 is an exploded perspective view showing the main parts of the writing core and the base member. FIG. 2 is a cross-sectional view showing another example of a writing instrument according to the present invention, taken along the line (II)-(II) in FIG.

This embodiment discloses the following features.
The first feature is that it comprises a barrel, a base member provided at the rear side of the barrel, and a writing lead that is detachably connected to the front end side of the base member with the writing part facing forward, and a rotation restriction part that prevents the writing lead from rotating in the circumferential direction is provided between the base member and the writing lead (see Figures 1 to 7).

The second feature is that the rotation restriction portion is composed of a small recess provided on one of the base member and the writing lead, which is recessed in a circumferential direction, and a small protrusion provided on the other of the two that fits into the small recess (see Figures 2 to 7).

The third feature is that one of the base member and the writing lead is provided with a mating recess with the small recess formed on the peripheral wall, and the other is provided with a mating protrusion that fits into the mating recess and has the small protrusion on the outer periphery (see Figures 2 to 7).

The fourth feature is that the peripheral wall of the mating recess has a tapered portion that guides the small protrusion in a forward diagonal circumferential direction when it advances and fits into the small recess (see Figures 2, 5, 6, and 7).

The fifth feature is that the inner peripheral surface of the mating recess and the outer peripheral surface of the mating protrusion are each provided with a mating projection that can be overcome when mating the mating protrusion with the mating recess (see Figures 3 to 6).

As a sixth feature, the inner peripheral surface of the mating recess and the outer peripheral surface of the mating protrusion are each provided with a fitting projection that is fitted over the mating recess when the mating protrusion is fitted into the mating recess, and the fitting projection of the mating recess and the fitting projection of the mating protrusion are provided to fit over the small protrusion after it enters the small recess (see Figures 3, 5, 6, etc.).

As a seventh feature, the barrel has a first radial width that is greater than a second radial width perpendicular to the first width, the writing part has a tip surface that is elongated in the radial direction, and the writing lead is connected to the base member with the elongated direction of the tip surface approximately aligned with the first width direction (see Figures 1 and 2).

The eighth feature is that the retractable writing instrument has a plurality of writing leads inside the barrel, and selectively projects the plurality of writing leads, and the direction in which the plurality of writing leads are arranged is substantially aligned with the first width direction (see FIG. 2).

The ninth feature is that the writing core is formed with an elliptical cross section (see Figure 7).

The tenth feature is that the writing core is provided in multiples and aligned in the minor axis direction of the ellipse in cross section (see Figure 7).

In addition, in the embodiments described below, the invention in which only the following constituent elements are essential is also disclosed.
That is, one aspect of the present invention is a writing instrument comprising a barrel, a base member provided at the rear side of the barrel, and a writing lead connected to the front end side of the base member with a writing portion facing forward, wherein the barrel has a first radial width that is greater than a second radial width perpendicular to the first width, the writing portion has a tip surface that is elongated in the radial direction, and the writing lead is connected to the base member with the elongated direction of the tip surface approximately coinciding with the direction of the first width (see Figures 1 and 2).
According to this invention, the writer or the like can recognize the longitudinal direction of the front end face of the writing part by the feel when gripping the barrel, and thus can perform writing actions quickly.

Another invention is a writing lead for a writing instrument, in which the ink reservoir is formed to have an elliptical cross section (see FIG. 7).
According to this invention, the ink storage portion having an elliptical cross section can store a relatively large amount of ink.

Furthermore, another invention is a writing instrument having the writing lead with the ink storage section within a barrel, and the writing leads are provided in multiple rows in the minor axis direction of the ellipse in the ink storage section (see Figure 7).
According to this invention, a plurality of writing leads can be efficiently stored in the space inside the barrel.

<First embodiment>
Next, specific embodiments having the above-mentioned features will be described in detail with reference to the drawings.

In this specification, the barrel axis direction means the direction along the barrel centerline, and the barrel circumferential direction means the direction around the barrel centerline. Additionally, "front" means one side of the barrel axis direction in which the writing lead protrudes, and "rear" means the opposite side to the one side.
In this specification, the barrel diameter direction means the diameter direction of the barrel perpendicular to the center line of the barrel, the barrel diameter outer side means the direction away from the barrel center along the barrel diameter direction, and the barrel diameter inner side means the direction toward the barrel center along the barrel diameter direction.

FIG. 1 shows an example of a writing instrument according to the present invention.
This writing instrument 1 comprises a barrel 10, a number of base members 20 provided at the rear of the barrel, a writing lead 30 removably connected to the front end of each base member 20 with the writing portion 30a facing forward, a divider 40 through which each of the base members 20 is inserted so as to be able to move forward and backward, and a biasing member 50 which biases each of the base members 20 rearward, and constitutes a retractable writing instrument in which, by selectively pushing and moving the multiple base members 20 (operating member), the writing lead 30 corresponding to the selected base member 20 appears and retracts at the front end of the barrel 10 (see Figure 1).

The barrel 10 is formed in a long, generally cylindrical shape, has a tapered tip 11 at its front end, and has a window 12 on the peripheral wall at its rear end that exposes the base member 20 (operating member). In addition, within the window 12, there are provided a guide surface 13 that guides the base member 20 in the forward and backward directions, and a latching portion 14 that latches the base member 20 when it moves forward (see FIG. 1).

In the illustrated example, the barrel 10 is composed of a front barrel 10a and a rear barrel 10b that is detachably connected to the opening at the rear end of the front barrel 10a. As an example other than the illustrated example, the barrel 10 can be composed of a single cylindrical member or three or more cylindrical members.

The barrel 10 has a first radial width W1 that is greater than a second radial width W2 that is substantially perpendicular to the first width W1 over substantially the entire length (see FIG. 2).
In other words, the cross-sectional shape of the barrel 10 is a generally elongated hole shape in which the first width W1 is greater than the second width W2.
As another example of the cross-sectional shape of the shaft tube 10, the cross-sectional shape may be an elongated hole shape, a rectangular shape, a diamond shape, or the like.

The base member 20 is an operating member for extending and retracting the writing portion 30a at the front end of the writing core 30, and is removably connected to the rear end side of the writing core 30 so that it advances and retreats integrally with the writing core 30.

This base member 20 is integrally made up of a long sliding body portion 21 that extends in the front-rear direction within the barrel 10, an operating portion 22 that protrudes from the rear end side of the sliding body portion 21 in the barrel radial direction outward and is exposed outside the barrel, a sliding convex portion 23 that protrudes on both sides in the circumferential direction on the inner side of the barrel radial direction of the sliding body portion 21, a locking portion 24 that protrudes rearward on the rear end side of the sliding body portion 21, a fitting convex portion 25 that fits into the rear end side of the writing core 30, a biasing member mounting portion 26 to which a biasing member 50 is attached in an annular shape, and a biasing member receiving portion 27 that receives the rear end of the biasing member 50 (see Figures 1 and 4).

When the operating portion 22 is pushed forward, the base member 20 advances while the sliding protrusion 23 slides against the guide surface 13 inside the barrel 10, sinking into the barrel, and the locking portion 24 locks with the locked portion 14 inside the barrel. When another base member 20 advances in the locked state, the base member 20 comes into contact with the advancing base member 20, thereby releasing the locked state.

The mating protrusion 25 on the front end side of the base member 20 has a forward-projecting mating protrusion 25a with a convex outer circumferential surface, and a small protrusion 25b that protrudes radially outward from the outer circumferential surface of the mating protrusion 25a.

The overhanging fitting protrusion 25a is generally conical in shape, gradually expanding in diameter toward the front, and its outer circumferential surface bulges radially outward in a convex vertical cross section (see Figures 5 and 6, etc.).

The small protrusions 25b are provided at intervals in the circumferential direction (two at equal intervals in the illustrated example). Each small protrusion 25b is formed in a rectangular parallelepiped shape that is long in the front-rear direction and is located rearward of the front end of the over-riding fitting protrusion 25a.

Multiple writing leads 30 (two in the illustrated example) are provided and spaced apart in the direction of the first width W1 of the barrel 10.

Each writing core 30 comprises a long, shaft-shaped filling 31, a pen shaft 32 connected to the front end of the filling 31 and extending forward, a roughly cylindrical case 33 that covers the filling 31 and the pen shaft 32, a cover member 34 that is movably attached to the front end of the case 33 and covers the writing part 30a at the front end of the pen shaft 32, a biasing member 35 that biases the cover member 34 forward, and a connected member 36 that is connected to the mating protrusion 25 at the front end of the base member 20 at the rear end of the case 33, forming a writing core for a marker pen.

This writing core 30 is non-rotatably connected to the base member 20 via a rotation restriction part X at the rear end side (see Figures 3 and 5, etc.).

The padding 31 is made of a thin cylindrical covering made of a number of synthetic fibers bundled together in an axial shape, and is impregnated with ink to form an ink reservoir.

The pen shaft 32 is a shaft-shaped bundle of fibers, and the ink flows forward due to the capillary force of the filling 31. At the front end of the pen shaft 32, a writing part 30a is formed for applying ink to the surface to be written on.

The writing part 30a is formed by processing the front end side of the pen shaft 32 into a wedge shape, so that its tip end surface is inclined with respect to the barrel axis direction when viewed from the side (see FIG. 1) and is formed into a rectangular shape that is elongated in the radial direction when viewed from the front (see FIG. 2). Writing part 30a with such a shape is sometimes called a chisel tip.
The writing core 30 is connected to the base member 20 with the longitudinal direction of the tip end surface of the writing portion 30a approximately coinciding with the direction of the first width W1.

The case 33 is roughly cylindrical and elongated in the front-rear direction, with its front end tapering in a stepped manner toward the front, and this tapered portion forms an annular recess 33a into which the rear end of the cover member 34 and the biasing member 35 are attached.

The annular recess 33a extends elongatedly in the front-to-rear direction so that the cover member 34 can move forward and backward by a predetermined amount.

The front end portion of the cover member 34 covers the writing portion 30a, and the rear end portion of the cover member 34 is fitted into the annular recess 33a so as to be movable forward and backward.
In addition, the biasing member 35 is a compression coil spring, and is mounted in an annular shape within the annular recess 33a with its front end abutting against the rear end of the cover member 34 and its rear end abutting against the rear end wall of the annular recess 33a, thereby biasing the cover member 34 forward.

According to this configuration, when the writing lead 30 advances, the cover member 34 comes into contact with the inner surface of the tip portion 11 and cannot advance. As a result, the writing part 30a protrudes from the front end of the cover member 34 and also protrudes from the opening at the front end of the barrel 10. During this movement, the biasing member 35 elastically contracts.
Furthermore, when the writing portion 30a is retracted into the barrel 10, as the writing lead 30 retracts, the cover member 34 moves relatively forward due to the biasing force of the biasing member 35, covering the writing portion 30a.

The connected member 36 also functions as a plug member that closes the rear end opening of the padding 31, and also functions as a member for connecting the writing core 30 to the base member 20.

More specifically, the connected member 36 is a generally bottomed tubular member with its front end at the bottom, and its outer circumferential surface is press-fitted into the inner circumferential surface of the rear end of the case 33 behind the padding 31. In FIG. 5, reference numeral 33b denotes an annular protrusion that is pressed against the outer circumferential surface of the connected member 36.
A cylindrical fitting recess 36 a having an opening at the rear and a bottom at the front end is formed at the rear of the connected member 36 so as to fit over the fitting protrusion 25 of the base member 20 .

The inner peripheral surface of the fitting recess 36a is formed with a small recess 36a1 formed by recessing a portion in the circumferential direction, and a riding-over fitting protrusion 36a2 which rides over and fits into the riding-over fitting protrusion 25a of the base member 20.
The peripheral wall of the fitting recess 36a is provided with a tapered portion 36a3 that guides the small protrusion 25b of the base member 20 in the forward oblique circumferential direction when the base member 20 advances so that the small protrusion 25b fits into the small recess 36a1 of the peripheral wall of the fitting recess 36a.

One or more (two in the illustrated example) small recesses 36a1 are provided on the peripheral wall of the fitting recess 36a.
Each small recess 36a1 is formed by recessing the inner circumferential surface of the fitting recess 36a radially outward and opening rearward (see FIG. 6).

The overriding fitting protrusion 36a2 is a protrusion that extends in the circumferential direction along the inner circumferential surface of the fitting recess 36a.
The over-fitting projection 36a2 is provided midway in the front-rear dimension of the small recess 36a1 so that after the advancing small convex portion 25b enters the small recess 36a1, over-fitting occurs midway along the advance.

The tapered portion 36a3 is an inclined surface that slopes forward along the inner circumferential surface of the mating recess 36a and continues from the rear end surface of the connected member 36 to the small recess 36a1.

The small convex portion 25b and the small concave portion 36a1 in the above configuration function as a rotation restriction portion X that prevents the writing core 30 from rotating in the circumferential direction between the base member 20 and the writing core 30.

The inner surface of the mating recess 36a fits loosely into the mating protrusion 25 so that the writing tip 30 can oscillate (see Figure 3).

The divider 40 is a generally disk-shaped member fixed to the inner circumferential surface of the barrel 10, and has multiple through holes 41 through which the multiple base members 20 can be inserted so that they can move forward and backward.

The biasing member 50 is a compression coil spring that is attached in an annular shape to the biasing member attachment portion 26 of the base member 20, with its front end engaged with the divider 40 and its rear end engaged with the base member 20, biasing the base member 20 rearward.

Next, the characteristic functions and effects of the writing instrument 1 having the above configuration will be described in detail.
When connecting the writing core 30 to the base member 20 during the manufacture of the writing instrument 1 or during replacement of the writing core 30, if the writing core 30 is retracted relative to the base member 20 with the axes of these two members aligned, the front end face of the small protrusion 25b slides against the tapered portion 36a3 at the rear end of the writing core 30, the writing core 30 rotates, and the small protrusion 25b on the base member 20 side is inserted into the small recess 36a1 on the writing core 30 side. During this insertion, the over-riding fitting protrusion 25a on the base member 20 side fits over the over-riding fitting protrusion 36a2 on the writing core 30 side. The writing core 30 can be removed from the fitting protrusion 25 by pulling it strongly.

When the writing instrument 1 is in use, the small recess 36a1 fits into the small protrusion 25b, so the writing core 30 does not rotate. This prevents the contact state between the inclined surface at the front end of the writing part 30a (chisel tip) and the surface being written on from becoming unstable, preventing the writer from drawing the intended line.

In addition, with the writing instrument 1, the first width W1 of the cross section of the barrel 10 is greater than the second width W2, so that the writer can recognize the longitudinal direction of the front end face of the writing portion 30a by the feel when gripping the barrel 10, and can therefore quickly perform writing operations using the writing instrument 1.

<Second embodiment>
Next, other embodiments of the present invention will be described. Note that the embodiments described below are modifications of the writing instrument 1 having the above-mentioned configuration, so the modifications will be mainly described in detail, and parts that function in substantially the same way will be given the same reference numerals, and duplicate detailed descriptions will be omitted.

The writing instrument 2 shown in Figure 7 is the same as the writing instrument 1 described above, except that the barrel 10 is replaced with a barrel 10' and the writing lead 30 is replaced with a writing lead 30'.

The shaft tube 10' is formed into a long cylindrical shape, consisting of one or more tubular members.

The writing core 30' is formed in an elliptical cross section, and multiple writing cores (two in the illustrated example) are provided inside the barrel 10' so that they are aligned in the minor axis direction of the ellipse in the cross section.

Each writing core 30' is the same as the writing core 30 described above, except that the padding 31, the portion of the case 33 around the padding 31, and the outer periphery of the connected member 36 are formed to have an elliptical cross section.

Therefore, the writing instrument 2 shown in FIG. 7 not only achieves the same effect as the writing instrument 1 described above, but also ensures a relatively large amount of ink in each writing lead 30'. Moreover, writing leads 30' with large amounts of ink can be efficiently arranged inside the barrel 10'.

<Other Modifications>
According to the above embodiment, the writing refill is configured as a writing refill for a marker pen, but this writing refill can be replaced with a ballpoint pen refill having a ballpoint pen tip connected to the front end of the ink containing tube, a mechanical pencil refill, a marker pen refill, an electronic pen refill, etc.
For example, when the writing lead is replaced with a mechanical pencil refill, the action of rotating the barrel is effective in eliminating uneven wear at the tip of the lead lead.

In addition, according to the above embodiment, the writing instrument is configured as a multiple retractable writing instrument, but the present invention can also be applied to writing instruments with a single retractable writing lead, or writing instruments with a fixed, non-retractable writing lead, etc. In the latter case, the base member 20 is not a sliding operating body, but a member fixed within the barrel.

Furthermore, according to the above embodiment, the mating protrusion 25 on the base member 20 side is fitted into the mating recess 36a on the writing core 30 side, but as another example, it is also possible to reverse the concave-convex relationship and fit the mating recess on the base member 20 side into the mating protrusion on the writing core 30 side.
Similarly, the relationship between the small recess 36a1 and the small protrusion 25b can be reversed.

In the above embodiment, the rotation restriction portion X is formed by the small recess 36a1 and the small protrusion 25b, but this rotation restriction portion may be any portion that prevents the writing lead from rotating in the circumferential direction. Other examples of this rotation restriction portion include a configuration in which one of the front end side of the base member and the rear end side of the writing lead is formed in a rectangular column shape and the other is formed in a rectangular hole shape that fits into the one, or a configuration in which one is formed in an elliptical column shape and the other is formed in an elliptical hole shape that fits into the one.

Furthermore, the present invention is not limited to the above-mentioned embodiments, and can be modified as appropriate without departing from the spirit and scope of the present invention.

1, 2: Writing implement 10, 10': Barrel 20: Base member 25: Fitting convex portion 25a: Overriding fitting protrusion 25b: Small protrusion 30, 30': Writing core 30a: Writing portion 36: Connected member 36a: Fitting recess 36a1: Small recess 36a2: Overriding fitting protrusion 36a3: Tapered portion X: Rotation restricting portion

Claims (8)

The pen comprises a barrel, a base member provided at the rear side of the barrel, and a writing core detachably connected to the front end side of the base member with a writing part facing forward,
A fitting recess is provided on one of the base member and the writing core, and a fitting protrusion that fits into the fitting recess is provided on the other of the base member and the writing core,
A rotation restricting portion that prevents the writing core from rotating in a circumferential direction is provided on the base member ,
A writing instrument characterized in that the rotation regulating portion is composed of a small recess formed by recessing a portion of the peripheral wall of the mating recess in the circumferential direction, and a small convex portion provided on the outer periphery of the mating convex portion and mating with the small recess . The writing implement according to claim 1, characterized in that a tapered portion is provided on the peripheral wall of the fitting recess so that the small protrusion is guided in a forward diagonal circumferential direction when advanced so as to fit into the small recess. The writing implement according to claim 1 or 2, characterized in that the inner peripheral surface of the mating recess and the outer peripheral surface of the mating protrusion are provided with a mating projection that is to be stepped over when the mating protrusion is fitted into the mating recess. an inner peripheral surface of the fitting recess and an outer peripheral surface of the fitting protrusion are each provided with a climbing-over fitting protrusion so as to climb over the fitting protrusion when fitting the fitting protrusion into the fitting recess;
3. The writing implement according to claim 1, wherein the over-fitting projection of the fitting recess and the over-fitting projection of the fitting protrusion are arranged to over-fit after the small protrusion enters the small recess. The barrel has a first radial width greater than a second radial width perpendicular to the first width,
The writing part has a tip surface that is elongated in a radial direction,
The writing implement according to any one of claims 1 to 4, characterized in that the writing lead is connected to the base member with the longitudinal direction of the tip surface approximately coinciding with the first width direction. A retractable writing instrument is configured by including a plurality of the writing leads in the barrel and selectively protruding the plurality of writing leads,
6. The writing implement according to claim 5, wherein the direction in which the plurality of writing leads are arranged substantially coincides with the first width direction. The writing implement according to any one of claims 1 to 6, characterized in that the writing core is formed with an elliptical cross section. 8. The writing implement according to claim 7, wherein the writing core is provided in a plurality of portions aligned in a minor axis direction of an ellipse in cross section.

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