JP2022115377A - Retractable writing instrument - Google Patents

Abstract

To effectively suppress impact and vibration associated with a writing action.SOLUTION: A retractable writing instrument includes in a shaft cylinder 10, a core 20 having a writing part 21 at its front end, an urging member 30 that urges the core 20 backward, a receiving member 41 that receives the core 20 from a rear side; a rotor 42 provided on a rear side of the receiving member 41 and rotatable and movable with respect to the shaft cylinder 10; and an annular resilient member 43 that faces the rotor 42 and resiliently forwards the receiving member 41 with a force greater than an urging force of the urging member 30, wherein by moving the rotor 42 forward against the urging force of the urging member 30 and engaging it with the shaft cylinder 10, the writing part 21 is protruded and a protruding state is maintained, and the receiving member 41 integrally includes a receiving portion 41a that receives a rear end of the core 20 from behind, and a shaft portion 41b that protrudes rearward from the receiving portion 41a, and the annular resilient member 43 is annularly attached to the shaft portion 41b, and the rotor 42 is fitted to the shaft portion 41b so as to be able to advance and retreat.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a retractable writing instrument in which a writing part retracts and retracts from the front end of a barrel by a knocking operation.

Conventionally, in this type of invention, as described in Patent Document 1, for example, a writing body that protrudes and retracts from the front end of the barrel inside the barrel, a return spring that biases the writing body backward, A second spring that receives and contracts the writing body from the rear side, and a rotor that is concavely fitted to the cylindrical portion on the backward side of the writing body and the second spring, and the rotor moves forward. is engaged with a barrel to hold the protruding state of the writing body.
In Patent Document 1, "By incorporating the second spring, a cushioning effect is obtained, and effects such as prevention of fatigue due to long-time writing, protection of the brush tip part by mitigation of impact such as dropping, and simplification of structure. will also be brought about.”

Japanese Utility Model Laid-Open No. 60-157284

However, according to the above-described prior art, there are cases where the cushioning effect of the second spring is not sufficiently exerted due to misalignment, bending, or the like of the writing body.

In view of such problems, the present invention comprises the following configurations.
A core having a writing part at its front end, a biasing member that biases the core backward, a receiving member that receives the core from the rear side, and a receiving member provided in the rear side of the receiving member. a rotor rotatable and retractable with respect to the barrel; and an annular elastic member facing the rotor and elastically pushing the receiving member forward with a force greater than the biasing force of the biasing member, The writing part is protruded by moving the rotor forward against the urging force of the urging member and engaging with the barrel, and the protruding state is maintained. A receiving portion that receives the rear end of the core from behind and a shaft portion that protrudes rearward from the receiving portion are integrally provided. A retractable writing instrument, characterized in that it is fitted to the shaft part so as to be able to move forward and backward.

INDUSTRIAL APPLICABILITY The present invention is configured as described above, so that it is possible to effectively suppress impacts and vibrations associated with writing operations.

BRIEF DESCRIPTION OF THE DRAWINGS It is a full cross-sectional view which shows an example of the writing instrument which concerns on this invention, (a) shows the state in which the writing part was immersed, and (b) shows the state in which the writing part protruded. It is a half sectional view which shows the rotor unit of the same writing instrument. In the same rotor unit, (a) shows a state in which the receiving member is in the initial position, and (b) shows a state in which the receiving member has retreated and is in contact with the rotor. It is an exploded perspective view of the same rotor unit. It shows how the rotor unit is assembled to the shaft tube. The shaft cylinder is shown in a full cross-sectional view, and the rotor unit is shown in a side view.

The present embodiment discloses the following features.
The first feature is that a core having a writing part at the front end thereof, a biasing member that biases the core backward, a receiving member that receives the core from the rear side, and the receiving member. and a rotor which is provided on the rear side of the shaft cylinder and is rotatable and retractable with respect to the shaft cylinder, and an annular spring that faces the rotor and springs the receiving member forward with a force greater than the biasing force of the biasing member. a member configured to move the rotor forward against the urging force of the urging member and engage the shaft tube to project the writing part and maintain the projecting state; The receiving member integrally includes a receiving portion that receives the rear end of the core from the rear and a shaft portion that projects rearward from the receiving portion. , the rotor is fitted to the shaft so as to be able to advance and retreat (see FIGS. 1 to 5).

As a second feature, the rotor is formed in a substantially cylindrical shape having a large-diameter portion and a small-diameter portion whose inner peripheral surface is reduced in diameter on the rear end side of the large-diameter portion. While covering the perimeter of the resilient member, the small diameter portion receives the rear end of the annular resilient member (see FIG. 2).

As a third feature, the shaft portion penetrates the annular elastic member and is movable forward and backward by a predetermined amount with respect to the engaged portion provided in the small diameter portion on the rear side of the annular elastic member. It has an engagement portion for engagement (see FIG. 2).

As a fourth feature, the engaged portion is a through-shaped circular hole, and the outer peripheral portion on the rear side of the engaging portion is press-fitted into the inner peripheral surface of the circular hole and passes through the circular hole. A press-fit portion and a loose insertion portion that is adjacent to the press-fit portion in the circumferential direction and passes through the circular hole without contacting the inner peripheral surface of the circular hole are provided (see FIGS. 2 and 4).

As a fifth feature, the shaft portion is provided with a sliding contact portion that is in sliding contact with the rotor in the front-rear direction (see FIG. 2).

As a sixth feature, the sliding contact portion includes a front sliding contact portion positioned forward of the annular elastic member and a rear sliding contact portion positioned rearward of the annular elastic member. (See Figure 2).

As a seventh feature, the receiving member is rotatably connected to the rotor (see FIGS. 2 and 4).

As an eighth feature, the rotor is movable forward and backward with respect to the shaft and is fitted so as not to be separated, and the receiving member, the rotor, and the annular elastic member are integrally formed. It constitutes a rotor unit (see FIGS. 2 and 5).

<Specific embodiment>
Next, specific embodiments having the above characteristics will be described in detail with reference to the drawings.

In this specification, the axial direction of the barrel means the direction in which the center line of the barrel extends, and the circumferential direction of the barrel means the direction around the center line of the barrel. Further, "front" means one side in the axial direction of the barrel and the direction in which the writing part protrudes, and "rear" means the side opposite to the one side.
Further, in this specification, the radial direction of the barrel means the diameter direction of the barrel perpendicular to the center line of the barrel, and the radially outer direction of the barrel means the direction away from the center of the barrel along the radial direction of the barrel. , and the inner side in the radial direction of the barrel means a direction toward the center of the barrel along the radial direction of the barrel.
Further, in this specification, the radial direction of the core means the diameter direction of the core perpendicular to the center line of the core, and the radial direction outside of the core means the direction away from the center of the core along the radial direction of the core. , and the inner side in the radial direction of the core means a direction toward the center of the core along the radial direction of the core.

This retractable writing instrument A comprises a barrel 10, a core 20 housed in the barrel 10 and having a writing part 21 at its front end, and a biasing member that biases the core 20 rearward within the barrel 10. 30, a rotor unit 40 that receives the core 20 from the rear side within the shaft tube 10, and a rotor unit 40 that can be engaged and disengaged from the rear side with the rear end side extending from the inside of the shaft tube 10 to the outside of the shaft tube 10. The writing part 21 is pivoted by moving the rotor 42 of the rotor unit 40 forward against the urging force of the urging member 30 and engaging it with the inner peripheral surface of the barrel 10. It is made to protrude from the front end of the cylinder 10 and the protruding state is maintained.

The shaft tube 10 is configured in a long tubular shape extending in the front-rear direction from one or more tubular members. The barrel 10 shown in the figure has a tapered cylindrical front end portion 11, a cylindrical front shaft 12 which is threadedly connected to the front end side of the front end portion 11, and the front shaft 12 is threadedly connected to the front end side. It is integrally constructed with a cylindrical rear shaft 13 to form an elongated substantially cylindrical shape.
In the drawing, reference numeral 14 denotes a cylindrical elastic grip fitted to the outer peripheral portion of the front shaft 12, and reference numeral 15 denotes a clip that opens and closes on the rear end side of the rear shaft 13. As shown in FIG.

An annular stepped portion 11 a whose diameter is reduced forward is provided on the inner peripheral surface of the tip portion 11 to engage the front end portion of the biasing member 30 .

On the rear end side of the inner peripheral surface of the rear shaft 13, there are a slide groove 13a for unrotatably advancing and retreating the rotor 42, a cam slope and a locking surface (Fig. not shown). For these configurations, for example, the structure described in JP-A-2018-149787 can be applied.

In addition, on the inner peripheral surface of the rear shaft 13, on the front side of the slide groove 13a and the cam slope, etc., there is provided a fitting projection 13b for fitting the rotor unit 40 rearward over the rear during assembly work ( See Figure 5).
A plurality of these fitting projections 13b are provided at intervals in the circumferential direction of the barrel.
Each stepping-over fitting projection 13b is a projection having a substantially mountain-shaped longitudinal section.

According to the illustrated example, the core 20 is a refill for a ballpoint pen, and has a long cylindrical ink tank 22 and a writing portion 21, which is a ballpoint pen tip, connected to the front end thereof.
Other examples of the core 20 include a refill for a mechanical pencil, a refill that constitutes an input pen (stylus pen) for electronic equipment, and the like.
A stepped portion 23 whose diameter decreases forward is provided on the front end side of the outer peripheral surface of the core 20 . The stepped portion 23 contacts the rear end of the biasing member 30 and receives a rearward biasing force (elastic force) of the biasing member 30 .

According to the illustrated example, the biasing member 30 is an annular resilient member, and has its front end in contact with the stepped portion 11a inside the barrel 10 and its rear end in contact with the stepped portion 23 of the core 20. In contact with each other, the center core 20 and the rotor unit 40 are urged rearward.
As another example of the biasing member 30, it is possible to use a tension coil spring that pulls the core 20 rearward.

The rotor unit 40 includes a receiving member 41 that receives the core 20 from the rear side, a rotor 42 that is provided on the rear side of the receiving member 41 and that can move forward and backward with respect to the shaft tube 10 and that can rotate. The receiving member 41 is integrally provided with an annular resilient member 43 that resiliently forwards with a force greater than the biasing force of the biasing member 30 .
When the rotor unit 40 moves forward against the biasing force of the biasing member 30 , the rotor unit 40 retains the writing part 21 in a projecting state by engaging with the inner surface of the barrel 10 .

The receiving member 41 is rotatably connected to the rotor 42 so as to move forward and backward by a predetermined amount.
The receiving member 41 includes a thin columnar receiving portion 41a that receives the rear end of the core 20 from behind, a shaft portion 41b that projects rearward from the center of the rear end surface of the receiving portion 41a, and around the shaft portion 41b. It integrally has a plurality of projections 41c projecting rearward from the rear end face of the receiving portion 41a.

The shaft portion 41b is formed in the shape of an elongated shaft penetrating the annular elastic member 43, and has a front side sliding contact portion 41b1 and a rear side sliding contact portion 41b31 (engagement portion 41b31) which are in sliding contact with the rotor 42 in the front-rear direction. joint).

The front side sliding contact portion 41b1 is a cylindrical surface located on the front side (left side according to FIG. 2) of the annular elastic member 43, and has a length in the front-rear direction so as to move the rotor 42 back and forth by a predetermined amount. is set appropriately.

The rear side of the front sliding contact portion 41b1 of the shaft portion 41b is formed to have a small diameter via a stepped portion 41b2. The stepped portion 41 b 2 receives the front end portion of the annular elastic member 43 .

A small-diameter portion 41b3 behind the stepped portion 41b2 of the shaft portion 41b is inserted through the annular elastic member 43. As shown in FIG. In the small diameter portion 41b3, a rear sliding contact portion 41b31 is provided on the rear side of the annular elastic member 43 so as to be in sliding contact with the engaged portion 42b1 of the rotor 42 in the front-rear direction.

The rear sliding contact portion 41b31 is a concave portion formed by recessing the outer peripheral surface of the small-diameter portion 41b3 over the entire circumference. The bottom surface of this annular recess is formed in a cylindrical shape.
The length of the rear sliding contact portion 41b31 in the front-rear direction is set so as to move the rotor 42 back and forth by a predetermined amount. functions as a department.

In the shaft portion 41b, the engaged portion 42b1 (circular hole) is press-fitted to the inner peripheral surface of the engaged portion 42b1 (circular hole) on the outer peripheral portion behind the rear sliding contact portion 41b31 (engaging portion). A press-fitting portion 41b32 is provided that protrudes radially outward in an arc shape so as to pass through 42b1. Furthermore, in the portion of the shaft portion 41b that is adjacent to the press-fitting portion 41b32 in the circumferential direction, a flat surface that penetrates the engaged portion 42b1 without contacting the inner peripheral surface of the engaged portion 42b1 (circular hole) is provided. A loose insertion portion 41b33 having a shape is provided.

Two press-fit portions 41b32 are provided symmetrically with the central axis therebetween. The outer diameters of these press-fit portions 41b32, 41b32 are slightly larger than the inner diameter of the engaged portion 42b1.
Two loosely inserted portions 41b33 are provided substantially parallel to each other with the central axis interposed therebetween.
It should be noted that the number of press-fitting portions 41b32 and loose insertion portions 41b33 may be a single number, a number other than the illustrated example, such as three or more, or a different shape having the same function.

Moreover, the projecting portion 41c protrudes rearward from the rear end surface of the receiving portion 41a and is provided in plurality at intervals in the circumferential direction.
The plurality of protrusions 41c abut on the front end surface of the rotor 42 when the receiving member 41 moves backward relative to the rotor 42 (see FIG. 3).

The rotor 42 can move forward and backward with respect to the shaft portion 41b and is fitted so as not to be separated. The rotor 42 is formed in a substantially cylindrical shape and has a large-diameter portion 42a and a small-diameter portion 42b formed by reducing the inner and outer peripheral surfaces on the rear end side of the large-diameter portion 42a.

The large diameter portion 42a is formed in a cylindrical shape extending from the front sliding contact portion 41b1 to the annular elastic member 43 and covering the periphery thereof.
The front end side of the inner peripheral surface of the large diameter portion 42a comes into sliding contact with the outer peripheral surface of the front side sliding contact portion 41b1 when the receiving member 41 advances and retreats relative to the rotor 42. As shown in FIG.

The small diameter portion 42 b is formed in a substantially cylindrical shape with an inner diameter smaller than the outer diameter of the annular elastic member 43 . An engaged portion 42b1 annularly protruding radially inward is provided on the rear end side of the small diameter portion 42b. The inner peripheral surface of the engaged portion 42b1 is a circular through hole.
The engaged portion 42b1 has a length in the front-rear direction shorter than that of the concave portion forming the rear sliding contact portion 41b31 so that it slides on the rear sliding contact portion 41b31 (engaging portion) and advances and retreats by a predetermined amount. set.

Further, on the outer peripheral side of the rotor 42, a projection 42c extending in the front-rear direction so as to be fitted in the slide groove 13a of the shaft cylinder 10 and guided forward and backward, and a knocking A cam slope 42d that slides on the cam slope 51 of the body 50 and the cam slope (not shown) of the barrel 10 is provided.

The annular elastic member 43 is accommodated in the cylindrical space between the shaft portion 41b and the rotor 42, and has a front end in contact with the stepped portion 41b2 and a rear end in contact with the front end face of the small diameter portion 42b, thereby 42, the receiving member 41 is pushed forward.
The illustrated annular elastic member 43 is a compression coil spring. The biasing force (elastic force) of the annular elastic member 43 is greater than the biasing force of the biasing member 30 .
As another example, the annular resilient member 43 may be made of an elastic material other than a spring, such as cylindrical rubber.

The knocking body 50 is a rod-shaped member that is knocked from behind.
The knock body 50 is formed in a substantially bottomed tubular shape with an open front end face and a closed rear end face, and a cam slope 51 for sliding contact with the cam slope 42d of the rotor 42 is formed on the front end face. ing. Further, the outer peripheral surface of the knock body 50 is provided with an engagement projection 52 that engages with the slide groove 13a in the barrel 10 to advance and retreat.

In the illustrated example, the knock body 50 is composed of two members, a cylindrical member and a member that closes the rear end of the cylindrical member. It is also possible to adopt a mode consisting of three members, a mode consisting of three or more members, or the like.
Further, according to the example shown in FIG. 1(b), when the writing unit 21 is in the projecting state, the knock body 50 can move back and forth in the space behind the rotor unit 40. Alternatively, the knock body 50 may be moved forward or backward by a biasing member (not shown) or the like.

Next, the characteristic functions and effects of the retractable writing instrument A having the above configuration will be described in detail.
When the knock body 50 is pushed forward in the initial state (see FIG. 1(a)), the engaging protrusion 52 of the knock body 50, the slide groove 13a in the barrel 10, the cam slope and locking surface (not shown), and the rotor Due to the action of the projection 42c and cam slope 42d of 42, the core 20 advances by a predetermined amount and the writing part 21 is held in a state of protruding from the front end of the barrel 10 (see FIG. 1(b)). These actions are substantially the same as those of the structure described in, for example, JP-A-2018-149787.
It should be noted that the mechanism for advancing the rotor unit 40 by a predetermined amount by external operation and locking it can be replaced with a structure other than the one described above.

When writing is performed while the barrel 10 is gripped by a writer or the like in the projecting state of the writing section 21 shown in FIG. be.
In more detail, since the rear end of the core 20 is received by the front end surface of the receiving member 41, the writing portion 21 is pressed against the surface to be written (for example, paper surface) and attached to the writing portion 21. When a rearward pressing force greater than the biasing force of the biasing member 30 is applied, the core 20 and the receiving member 41 retreat against the elastic force of the annular elastic member 43 . That is, the dimension W (see FIGS. 2 and 3) between the rear end of the protrusion 41c of the receiving member 41 and the front end of the rotor 42 is reduced.

After that, when the pressing force is released, the core 20 and the receiving member 41 move forward due to the elastic force of the annular elastic member 43 . That is, this forward movement increases the dimension W between the rear end of the protrusion 41c of the receiving member 41 and the front end of the rotor 42 .

Therefore, for example, even if vibration occurs in the axial direction of the barrel due to repeated actions of pressing the writing portion 21 against and away from the writing surface during writing, the vibration is absorbed by the cylindrical portion around the shaft portion 41b. It can be absorbed by the elasticity of the annular resilient member 43 that expands and contracts within the space.
Moreover, when the receiving member 41 is vibrated, the front sliding contact portion 41b1 and the rear sliding contact portion 41b31 are brought into sliding contact with the rotor 42, so that the receiving member 41 moves back and forth smoothly without rattling. Moreover, the receiving member 41 is rotatable with respect to the rotor 42 .
Therefore, according to the retractable writing instrument A, the transmission of the vibration and impact of the core 20 to the barrel 10 due to the writing operation can be effectively prevented without being affected by misalignment, deflection, etc. of the core. It can be suppressed, and in turn, a soft writing feeling can be given to the writer.

Next, the effects of manufacturing the retractable writing instrument A will be described.
As shown in FIG. 4, when assembling the rotor unit 40, the annular resilient member 43 is annularly attached to the shaft portion 41b of the receiving member 41, and rotates so as to cover the shaft portion 41b and the annular resilient member 43. Child 42 is attached.
More specifically, the shaft portion 41b has a press-fitting portion 41b32 and a loose insertion portion 41b33 on the front end side that protrude rearward from the annular resilient member 43, and are press-fitted into and penetrate the circular hole-shaped engaged portion 42b1. .
At this time, the arc-shaped press-fitting portion 41b32 is in sliding contact with the inner peripheral surface of the engaged portion 42b1, but the planar loosely-inserted portion 41b33 is not in contact with the inner peripheral surface of the engaged portion 42b1, so the press-in force is relatively small. can be easily assembled.
After the press-fit portion 41b32 passes through the engaged portion 42b1 rearward, the rear end portion of the press-fit portion 41b32 is engaged with the front end portion of the circular hole-shaped engaged portion 42b1, and the shaft portion 41b is It will not come off from the engaged portion 42b1. That is, the rotor 42 can move forward and backward with respect to the receiving member 41 and cannot be separated.
Therefore, the receiving member 41 , the rotor 42 and the annular resilient member 43 can be treated as an integrated rotor unit 40 .

Then, as shown in FIG. 5, the rotor unit 40 configured as described above is inserted into the front shaft 12 from the front side, climbs over the overfitting projection 13b, and moves to the rear of the overfitting projection 13b.
More specifically, the ring-shaped flange 42e on the front end side of the rotor 42 is positioned rearward of the jump-over fitting projections 13b, so that the entire rotor unit 40 including the rotor 42 is fitted with the jump-over fitting projections. It stops moving forward beyond 13b.
Therefore, even when the rear shaft 13 is removed from the front shaft 12 and the core 20 is pulled out for replacement of the core 20 or the like, the rotor unit 40 can be prevented from falling off from the rear shaft 13. .

According to the above-described embodiment, as a particularly preferable embodiment, the receiving member 41 is engaged with the rotor 42 so as not to be pulled out. , a structure in which the rotor 42 and the receiving member 41 are separated in the axial direction is also possible.

Moreover, the present invention is not limited to the embodiments described above, and can be modified as appropriate without changing the gist of the present invention.

10: Axle cylinder 13b: Overpass fitting projection 20: Core 21: Writing part 30: Biasing member 40: Rotor unit 41: Receiving member 41a: Receiving part 41b: Shaft part 41b1: Front sliding contact part 41b31: Rear side Sliding contact part (engagement part)
41b32: press fitting portion 41b33: loose insertion portion 42: rotor 42a: large diameter portion 42b: small diameter portion 42b1: engaged portion (circular hole)
43: Annular elastic member A: Writing instrument

Claims (8)

A core having a writing part at its front end, a biasing member that biases the core backward, a receiving member that receives the core from the rear side, and a receiving member provided in the rear side of the receiving member. a rotor rotatable and retractable with respect to the barrel; and an annular elastic member facing the rotor and elastically pushing the receiving member forward with a force greater than the biasing force of the biasing member, The writing part is protruded by advancing the rotor against the urging force of the urging member and engaging with the barrel, and the protruding state is maintained;
The receiving member integrally includes a receiving portion for receiving the rear end of the core from the rear and a shaft portion projecting rearward from the receiving portion,
The annular resilient member is annularly attached to the shaft,
A retractable writing instrument, wherein the rotor is fitted to the shaft so as to move back and forth. The rotor is formed in a substantially cylindrical shape having a large-diameter portion and a small-diameter portion whose inner peripheral surface is reduced in diameter on the rear end side of the large-diameter portion. 2. The retractable writing instrument according to claim 1, wherein the rear end of the annular elastic member is received by the small-diameter portion. The shaft portion penetrates through the annular elastic member, and is positioned behind the annular elastic member and engages an engaged portion provided in the small diameter portion so as to advance and retreat by a predetermined amount. 3. The retractable writing instrument according to claim 2, characterized by comprising: The engaged portion is a penetrating circular hole,
A press-fitting portion that is press-fitted into the inner peripheral surface of the circular hole and passes through the circular hole is provided on the outer peripheral portion on the rear side of the engaging portion, and the press-fitting portion is circumferentially adjacent to the press-fitting portion and inside the circular hole. 4. The retractable writing instrument according to claim 3, further comprising a loose insertion portion that passes through the circular hole without contacting the peripheral surface. 5. The retractable writing instrument according to any one of claims 1 to 4, wherein the shaft portion is provided with a sliding contact portion that slides in the longitudinal direction with respect to the rotor. The slide contact portion includes a front slide contact portion located forward of the annular elastic member and a rear slide contact portion located rearward of the annular elastic member. Item 5. The retractable writing instrument according to item 5. 5. The retractable writing instrument according to claim 1, wherein said receiving member is rotatably connected to said rotor. The rotor is movable forward and backward with respect to the shaft and is fitted so as not to be separated, and the receiving member, the rotor, and the annular elastic member constitute an integral rotor unit. The retractable writing instrument according to any one of claims 1 to 4, characterized in that

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