JP2019111658A - Multicore writing utensil - Google Patents

Abstract

To provide a multicore writing utensil that can prevent rattling of a chip during writing to achieve a stable writing feeling and does not need high-accurate dimension management of components.SOLUTION: The multicore writing utensil comprises: a barrel having an opening at a front end thereof; a plurality of chip holders that can move in a shaft direction of the barrel; chips that can be retracted accompanying movements of the chip holders; annular members that are freely fitted to outer peripheries of the chips to be movable in the shaft direction; and elastic members that connect the chip holders to the annular members so that the holders and the members can move relatively to each other. In at least part of an outer periphery of the annular member is formed a contact surface tapered toward a front end thereof, and in a part of the annular member is formed a notch, where an inner diameter of the annular member is reduced when the contact surface receives a load. In a part of an inner surface of the barrel is formed a guide surface tapered toward the front end thereof, and the contact surface receives the load from the guide surface accompanying movement of the chip holder toward the front end.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a multifilament writing instrument. In particular, the present invention relates to a multi-core writing instrument capable of accommodating a plurality of writing materials in a barrel.

  Patent Document 1 discloses a multi-core writing tool which slides in the front-rear direction with respect to a barrel and draws out the writing portion of the writing body from the opening of the barrel. An annular member is disposed on the outer periphery of the tip end portion of each writing body, and a substantially spherical inner surface on which the annular member abuts is formed on the inner side surface around the opening of the tip end of the barrel where the writing portion appears. The annular member is fixed to the writing body via a spring and biased forward. When the writing unit is extended, the elastic force of the spring brings the annular member into close contact with the inner surface of the end of the barrel. This can prevent rattling at the time of writing.

JP 2013-220602

  In the technique disclosed in Patent Document 1, in order to enhance the effect of preventing rattling during writing, it is necessary to appropriately manage the dimensional relationship between the inner surface of the annular member and the outer peripheral surface of the writing portion. For example, if the gap dimension between the outer peripheral surface of the writing part and the inner surface of the annular member is larger than the gap size between the outer peripheral surface of the writing part and the inner surface of the tip of the barrel, rattling during writing is prevented. I can not get the effect. For this reason, high dimensional accuracy is required, and there is a problem in productivity.

  The present invention has been made in view of the above findings, and the object of the present invention is to prevent the rattling of the chip at the time of writing and obtain a stable writing feeling, while controlling the dimensions of parts with high accuracy. Providing a multi-core writing instrument that does not require

  According to the present invention, a shaft cylinder having an opening at its front end, a plurality of chip holders housed inside the shaft cylinder and movable in the axial direction of the shaft cylinder, and fixed to the front ends of the respective chip holders The chip is loosely fitted on the outer periphery of each chip or chip holder fixed to each chip or each chip, and can be moved in the axial direction of the chip with respect to the chip. Annular member, and an elastic member connecting the chip holder and the annular member so as to be able to move relative to each other, wherein at least a part of the outer periphery of the annular member is connected to the annular member. An abutment surface is formed to abut on a part of the inner surface of the cylinder with movement to the front end side, a notch is formed on a part of the annular member, and the abutment surface is Receiving a load At the same time, the inner diameter of the annular member is reduced, and a part of the inner surface of the barrel is formed with a guide surface with which the contact surface abuts with the movement of the tip holder toward the front end. The contact surface receives the load from the guide surface as the tip holder connected to the annular member having the contact surface moves to the front end side. It is a multi-core writing instrument.

  According to the present invention, the contact portion of the annular member receives a load from the guide surface of the barrel with the movement of the tip holder toward the front end side, whereby the inner diameter of the annular member is determined by the presence of the notch of the annular member. Decreases in diameter. As a result, the barrel and the annular member cooperate with each other to grip the chip or the chip holder without rattling (play). Furthermore, since the chip holder and the annular member are connected to be movable relative to each other by the elastic member, the chip or the chip holder does not have to control the dimension of the inner diameter of the annular member with high accuracy. Can be guaranteed to be effectively gripped in a manner without rattling (play).

  Preferably, a plurality of the notches are arranged at equal intervals in the circumferential direction of the annular member, and each of the plurality of notches is a slit extending in the axial direction of the annular member. In this case, the inner diameter of the annular member can be reduced in the circumferential direction with good balance.

  The abutment surface is preferably tapered towards the front end, and the guiding surface is also preferably tapered towards the front end. The abutment surface preferably has, for example, a frusto-conical surface. In this case, the guide surface is preferably a corresponding concave frusto-conical surface. Alternatively, it is preferable that the contact surface has a convex curved surface rotationally symmetric about an axis. In this case, it is preferable that the guide surface is a concave surface or a concave frusto-conical surface that is rotationally symmetric about an axis and has a curvature gentler than the curvature of the convex surface.

  Preferably, the elastic member is a cylindrical resin spring member in which a large number of slits extending in a direction perpendicular to the axial direction are formed. In this case, preferably, the annular member and the resin spring member are integrally molded from the same resin material.

  Preferably, one of the plurality of chip holders holds the friction member as a chip. The friction member is an eraser or a frictional heat generating rubber (erasing rubber) for a thermochromic writing instrument. In this case, it is possible to prevent the friction member from rattling at the time of handwriting erasure, and a more stable handwriting erasure feeling can be obtained.

  Further, on the rear end side of each chip holder, an operating body having an operating portion is provided, and in the side wall of the shaft cylinder, a plurality of window holes extending in the longitudinal direction are distributed and penetrated in the radial direction. The operating portion of each operating body protrudes radially outward from the corresponding window hole, and an operating body corresponding to the operating portion when the operating portion is slid forward inside the shaft cylinder And a plurality of coil springs for urging each of the plurality of chip holders rearwardly are provided inside the shaft cylinder. The front end sides of the plurality of coil springs are supported by a spring support fixed to the barrel, and the spring support includes a plurality of inner holes through which the plurality of chip holders can be inserted. It is preferred to be provided There.

  According to the present invention, the contact portion of the annular member receives a load from the guide surface of the barrel with the movement of the tip holder toward the front end side, whereby the inner diameter of the annular member is determined by the presence of the notch of the annular member. Decreases in diameter. As a result, the barrel and the annular member cooperate with each other to grip the chip or the chip holder without rattling (play). Furthermore, since the chip holder and the annular member are connected to be movable relative to each other by the elastic member, the chip or the chip holder does not have to control the dimension of the inner diameter of the annular member with high accuracy. Can be guaranteed to be effectively gripped in a manner without rattling (play).

It is a schematic longitudinal cross-sectional view of the multicore writing instrument in one Embodiment of this invention, Comprising: It is a figure which shows the state which all the chips (writing material) have not protruded. It is an enlarged longitudinal cross-sectional view of the front-end | tip part of the multicore writing instrument of FIG. It is the BB sectional drawing of FIG. Fig.4 (a) is a side view of the chip | tip of the multi-core writing instrument of FIG. 1, a chip holder, an annular member, and an elastic member. FIG.4 (b) is the sectional view on the AA line of Fig.4 (a). Fig.5 (a) is a perspective view of the chip holder of the multi-core writing instrument of FIG. 1, an annular member, and an elastic member. FIG.5 (b) is a longitudinal cross-sectional view of the chip holder of FIG.5 (a), an annular member, and an elastic member. It is a schematic longitudinal cross-sectional view of the multicore writing instrument of FIG. 1, Comprising: It is a figure which shows the state which one tip (writing body) protrudes. FIG. 7 is an enlarged vertical cross-sectional view of a tip portion of the multicore writing instrument of FIG. 6; It is the CC sectional view taken on the line of FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic vertical cross-sectional view of a multi-core writing instrument 101 according to an embodiment of the present invention, showing a state in which all the chips (writing elements) are not protruded. 6 is a schematic vertical cross-sectional view of the multi-core writing instrument 101 of FIG. 1, showing a state in which a ballpoint pen tip, which is an example of a writing material, protrudes.

  As shown in FIGS. 1 and 6, the multi-core writing instrument 101 according to this embodiment has a front shaft 103 made of a tapered cylindrical body, and a cylindrical shape attached to the rear end of the front shaft 103 by screwing or press fitting. And a rear barrel 104, and an axial cylinder 102 consisting of: At the front end of the front shaft 103, an opening 131 through which the tip 161 of the writing body 106 can project is axially penetrated. The front shaft 103 and the rear shaft 104 are formed of synthetic resin (for example, polycarbonate etc.) or metal.

  On the side wall at the rear of the rear shaft 104, for example, five (which may be selected from 2 to 6) elongated and elongated window holes 141 (see FIG. 6) extending in the front-rear direction are radially penetrated. The five window holes 141 are formed at equal intervals in the circumferential direction, for example.

  A release bar 143 extending in the front-rear direction is extended in a region on the axial center side inside the five window holes 141 of the rear shaft 104. The front end of the release bar 143 is supported by a spring support 109 described later. On the other hand, a locking wall portion 143a extending in the front-rear direction is formed on the inner surface of the side wall between the five window holes 141 of the rear shaft 104, and the locking wall portion 143a has a state in which the pen tip protrudes. The rear end of the operation body 107 of the writing body 106 can be locked. Then, when the rear end of the operating body 107 of the writing body 106 in a state where the pen tip protrudes is locked to the locking wall portion 143a, the other writing can be made to cause the other writing body 106 to protrude instead. When the operating body 107 of the body 106 is moved forward, the operating body 107 of the other writing body 106 presses the release bar 143 radially outward, and the pressed release bar 143 is the locking wall portion The rear end of the operation body 107 locked to the shaft 143a is pressed radially outward to release the locked state. In addition, a clip 144 is provided at one position on the outer surface of the side wall between the five window holes 141 of the rear shaft 104.

  At a rear end portion of the rear shaft 104, a lid portion 105 which allows the rear end portion to be freely opened and closed is rotatably provided. One end of the lid 105 may be pivotably connected to the base of the clip 144 by a hinge, for example. The hinge portion can be extended, for example, in the left-right direction of the clip 144 when the clip 144 is viewed from the front with the pen tip downward. In this case, the lid portion 105 can be pivotable substantially in the front-rear direction.

  A contact wall is formed on the front surface of the lid 105. The rear end of the operation body 107 connected to the rear end of the writing body 106 in the embedded state is configured to be held against the contact wall portion (see FIG. 1). As the hinge portion, typically, a configuration in which it is rotatably connected by a rotation shaft may be adopted, but besides the aspect, a flexible connection portion or the like capable of bending and deforming may also be adopted. .

  Then, for example, an engagement portion is provided on the front surface of the other end of the lid portion 105 (for example, an engagement recess or an engagement hole portion), and the rear end of the rear shaft 104 is engaged with the engagement portion. Possible engaged parts may be provided (e.g. engaging projections). More specifically, an inward projection can be formed on the inner surface of the engagement portion (engagement recess or engagement hole), and the inward projection can be engaged with the outer surface of the engagement portion (engagement projection). Outward projections can be formed.

  In this case, the engaging portion and the engaged portion are engaged with each other while the lid portion 105 closes the rear end opening (the inward protrusion and the outward protrusion are in the overengaged state). The engagement state is not released by the contact between the operation body 107 and the contact wall portion of the lid portion 105 by the rearward biasing of the coil spring 108 described later, and the lid portion 105 does not open.

  Each operating body 107 has an operating portion 171, a front side projecting portion 172, a rear side projecting portion 173, a fitting portion 174, and a collar portion 175, as particularly shown in FIG. The operating portion 171 is formed at the rear end portion of the operating body 107 and protrudes to the outside from the window hole 141 of the shaft cylinder 102. The rear side projecting portion 173 is provided on the opposite side (axial center side) of the operating portion 171 of the operating body 107, the front side projecting portion 172 is provided on the front side of the rear side projecting portion 173, and the fitting portion 174 is an operating body It is formed at the front end portion of 107 and is fitted into the rear end opening of the ink storage cylinder 163. The collar portion 175 is formed in the vicinity of the rear of the insertion portion 174, and the front surface of the collar portion 175 presses the rear end of the coil spring 108.

  Further, locking projections (not shown) are formed on both side surfaces of the operation body 107, and the locking projections can be engaged with both side walls of the window hole 141 in a locking manner. The operating body 107 is obtained by a molded body of a synthetic resin (for example, polypropylene resin, ABS resin, polyacetal resin, etc.).

  When the tip 161 of the writing material 106 is in the immersive state, the rear end portion of the operating object 107 attached to the writing material 106 is in a state where it is held against the contact wall (see FIG. 1). reference). On the other hand, when the tip 161 of the writing body 106 is in the projecting state, the rear side projecting portion 173 of the operating body 107 attached to the writing body 106 is engaged with the locking wall portion 143 a formed inside the shaft cylinder 102. It is in the stopped state (see FIG. 6).

  In addition, the front protrusion 172 of the operating body 107 connected to the writing body 106 in the tip-immersed state is another writing that is in the projecting state first when the operating portion 171 of the operating body 107 is slid forward. If there is the body 106, the release bar 143 with which the rear side projecting portion 173 of the operating body 107 connected to the other writing body 106 is in contact is pressed to the rear side projecting portion 173 and the locking wall portion 143a Is released, that is, the tip projecting state of the other writing instrument 106 is released.

  On the other hand, a cylindrical spring support 109 is provided in the inside of the shaft cylinder 102 (inside of the rear shaft 104). In the spring support 109, five inner holes through which the writing bodies 106 are respectively inserted are axially penetrated. Then, on the rear surface side of the spring support 109, coil springs 108 are disposed corresponding to the respective inner holes. The writing body 106 is loosely inserted in the inner holes 191 and the coil springs 108, and the front surface of the collar portion 175 of the operation body 107 presses the rear end of the coil spring 108.

  More specifically, in the rear end surface of the spring support 109, a cylindrical recess is formed corresponding to each inner hole. The outer surface of the front end portion of each coil spring 108 is press-fitted and held in each recess. As a result, when the writing instrument 106 (and the operating body 107) is replaced, the coil spring 108 is prevented from falling off during the replacement operation.

  Each coil spring 108 always biases each operation body 107 (i.e., each writing element 106) backward. That is, each coil spring 108 maintains a compressed state (that is, a state in which the writing instrument 106 is urged rearward) in both the tip projecting state and the tip inserting state. Thereby, back and forth rattling of the operation body 107 is prevented. However, each coil spring 108 is in a non-compressed state (free state) in a state where the writing body 106 is not inserted therein (for example, a state in which the writing body is being replaced).

  Subsequently, FIG. 2 is an enlarged vertical cross-sectional view of the tip portion of the multi-core writing instrument 101 of FIG. 1, and FIG. 3 is a cross-sectional view taken along line B-B of FIG. 4 (a) is a side view of the tip 161, the tip holder 162, the annular member 165, and the elastic member 164 of the multi-core writing instrument 101 of FIG. 1, and FIG. 4 (b) is a side view of FIG. It is an AA line sectional view. 5 (a) is a perspective view of the tip holder 162, the annular member 165 and the elastic member 164 of the multi-core writing instrument 101 of FIG. 1, and FIG. 5 (b) is the tip holder 162, the annular member 165 and FIG. 16 is a longitudinal sectional view of an elastic member 164.

  As shown in FIGS. 5A and 5B, in the present embodiment, the chip holder 162, the annular member 165, and the elastic member 164 are integrally formed. The rear end portion of the tip holder 162 is a small diameter portion 162 a for fitting with the front end portion of the ink containing cylinder 163. On the other hand, as shown in FIGS. 4B and 5B, the front end portion of the chip holder 162 is provided with a fitting hole 162h in which the small diameter portion 161a of the rear end portion of the chip 161 is fitted. The tip 161 of the present embodiment is a ballpoint pen tip.

  Further, as shown in FIG. 3 and FIG. 4B in particular, an annular member 165 made of resin (for example, made of polyacetal) is loosely fitted around the tip 161. The annular member 165 of the present embodiment is integrally molded with the cylindrical resin spring member 164 on the proximal end side. A large number of slits 164s extending in a direction perpendicular to the axial direction are formed in the resin spring member 164, and can be expanded and contracted in the axial direction.

  As shown in FIGS. 4 (a), 4 (b), 5 (a) and 5 (b), the resin spring member 164 of this embodiment has a pair of substantially semicircular slits 164s facing each other in the vertical direction. And four pairs of substantially semicircular slits 164s facing to the left and right are alternately formed in pairs in the axial direction. The remainder between the pair of slits 164s is called a rib 164b. Further, in the present embodiment, the width (axial direction length) of each slit 164s is uniform, and the axial distance between the slits 164s axially adjacent is also uniform, and both are the same. However, these dimensional relationships may be appropriately adjusted as described below in order to achieve the desired degree of elasticity.

  Further, the base end side of the resin spring member 164 is integrated with the front end side of the chip holder 162. Thus, as shown in FIG. 7, the annular member 165 is movable in the axial direction of the tip 161 with respect to the tip 161 in accordance with the expansion and contraction of the resin spring member 164.

  Further, as shown in FIG. 5 (a), in the front side region of the outer periphery of the annular member 165, a frustoconical contact surface 165t is formed as a tapered contact surface toward the front end. There is. A cylindrical portion 165a is continuously provided on the rear side of the contact surface 165t, and a cylindrical resin spring portion 164 having the same diameter as the cylindrical portion 165a is provided on the rear side. In the present embodiment, the inner diameter of the resin spring portion 164 is the same as the inner diameter of the portion corresponding to the contact surface 165t.

  The annular member 165 of the present embodiment is provided with four slits 165 s as notches. As shown in FIG. 5A, the four slits 165s are arranged at equal intervals (every 90 °) in the circumferential direction of the annular member 165. In addition, the four slits 165 s extend in the axial direction of the annular member 165 from the front end to near the rear end of the cylindrical portion 165 a. Thus, when a load is received at the contact surface 165t, the inner diameter of the annular member 165 is flexibly reduced, and when the load is released, the inner diameter of the annular member 165 is elastically restored. It is supposed to

  Further, as shown in FIG. 2, in the vicinity of the opening 131 of the front shaft 103, a concave frusto-conical guide surface 103t is formed as a guide surface tapered toward the front end. Thereby, the contact surface 165t receives a load from the guide surface 103t along with the movement of the writing body 106 to the front end side (FIG. 1 to FIG. 6).

  The multi-core writing instrument 101 configured as described above operates as follows.

  As shown in FIGS. 1 and 2, when all writing materials 106 are in the retracted state, the operating portion 171 of one operating body 107 is selected, and the window hole 141 against the backward bias of the coil spring 108. When the sliding operation is performed forward along the direction, the tip 161 of the writing body 106 connected to the operation body 107 is protruded to the outside from the opening 131 of the barrel 102. Then, the rear side projecting portion 173 of the operating body 107 that has been slid forward is newly locked to the locking wall portion 143a inside the shaft cylinder 102, and the tip projecting state thereof is maintained.

  Alternatively, when the other writing body 106 is in the projecting state, the operation portion 171 of one operation body 107 is selected, and the sliding operation is performed forward along the window hole 141 against the backward bias of the coil spring 108 Then, the front protrusion 172 of the operating body 107 presses the release bar 143 in the state of being in contact with the rear protrusion 173 of the other writing object 106 radially outward. As a result, the locked state between the locking wall portion 143a and the rear side protruding portion 173 is released, and the other writing body 106 is moved rearward by the rear biasing of the coil spring 108, that is, in the barrel 102. Immersed in Simultaneously with the insertion of the other writing body 106, the tip 161 of the writing body 106 connected to the operation body 107 which has been slid forward is protruded to the outside from the opening 131 of the barrel 102. Then, the rear side projecting portion 173 of the operating body 107 that has been slid forward is newly locked to the locking wall portion 143a inside the shaft cylinder 102, and the tip projecting state thereof is maintained.

  7 is an enlarged vertical cross-sectional view of the tip portion of the multi-core writing instrument 101 of FIG. 6, and FIG. 8 is a cross-sectional view taken along the line C-C of FIG. As shown in FIGS. 6 to 8, in any of the above cases, the contact surface 165 t of the annular member 165 loads the load from the guide surface 103 t of the front shaft 103 along with the movement of the writing body 106 to the front end side. receive. At this time, the inner diameter of the annular member 165 is reduced by the presence of the four slits 165 s of the annular member 165. As a result, as shown in FIG. 8, the front shaft 103 and the annular member 165 cooperate with each other to grip the tip 161 without rattling (play).

  Furthermore, since the tip holder 162 and the contact surface 165t of the annular member 165 can be moved relative to each other by the expansion and contraction action of the resin spring member 164, dimensional control of the diameter of the inner diameter of the annular member 165 etc. is performed with high accuracy. Even if not, it can be ensured that the tip 161 is effectively gripped in a rattling-free manner.

  After that, for example, when the tip 161 which has been projected so far is inserted rearward by the backward biasing of the coil spring 108 in accordance with the operation of projecting another writing object, the contact surface 165t of the annular member 165 The load received from the guide surface 103t disappears. Along with this, the inner diameter of the annular member 165 which has been reduced in diameter returns to the original state (FIG. 8 → FIG. 3).

  In addition, when replacing the writing material 106, the operation end on the opposite side to the hinge of the lid 105 is back from the state where the lid 105 closes the rear end opening of the barrel 102 (see FIG. 1) The rear end opening portion of the shaft cylinder 102 is opened by releasing the engagement between the engaging portion and the engaged portion and rotating the lid portion 105 rearward. At the same time, each operating body 107 is projected rearward from the opening 142 by the rearward biasing of the coil spring 108. By taking out the operating body 107 from this state, it is possible to take out the writing body 106 connected to the operating body 107 from the inside of the shaft cylinder 102.

  Thereafter, a new writing material 106 (and a new operating object 107) is inserted into the barrel 102 through the rear end opening. Then, each operating body 107 is brought into contact with the contact wall portion of the lid portion 105, and the lid portion 105 is rotated forward so as to press each operating body 107 forward, and the engaging portion and the engaged portion are engaged. And the lid 105 is closed. Along with this, the front surface of the collar portion 175 of the new operation body 107 is in a state of pressing the rear end of the corresponding coil spring 108, and the replacement work of the writing body 106 (and the operation body 107) is completed.

  As described above, according to the multi-core writing instrument 101 of the present embodiment, the contact surface 165 t of the annular member 165 is the guide surface of the front shaft 103 with the movement of the writing body 106 (including the tip holder 162) to the front end. By receiving a load from 103t, the inner diameter of the annular member 165 is reduced due to the presence of the slit 165s of the annular member 165. As a result, the front shaft 103 and the annular member 165 cooperate with each other to grip the tip of the tip 161 without rattling (play). Furthermore, the chip 161 and the contact surface 165t of the annular member 165 are connected relative to each other by the resin spring member 164 so that dimensional control of the diameter of the inner diameter of the annular member 165, etc. can be performed with high accuracy. Even if not, it can be ensured that the tip 161 is effectively gripped in a rattling-free manner.

  Further, according to the multi-core writing instrument 101 of the present embodiment, four slits 165 s as notches are arranged at equal intervals in the circumferential direction of the annular member 165, and each slit 165 s is in the axial direction of the annular member 165 Because of the extension, the inner diameter of the annular member 165 can be reduced in the circumferential direction in a well-balanced manner.

  Further, the abutment surface 165t of the annular member 165 receives a load with good balance in the circumferential direction because the abutment surface 165t and the guide surface 103t are in the form of corresponding truncated cones and concave cones, respectively. As a result, the annular member 165 can be reduced in diameter in a well-balanced manner in the circumferential direction. Thus, preferably, the abutment surface 165t and the guide surface 103t are tapered toward the front end. The tapered abutment surface 165t can also be formed by providing R around the front end of the cylindrical annular member 165. Further, the tapered contact surface 165t has a convex curved surface rotationally symmetric about the axis, and the tapered guiding surface 103t is rotationally symmetric about the axial line and is more gentle than the curvature of the convex curved surface It may be a concave curved surface or a concave truncated conical surface of curvature.

  In the multicore writing instrument 101 of the present embodiment, the annular member 165 is movable in the axial direction in the region of the tip 161, and the region of the tip 161 is gripped when the diameter of the annular member 165 decreases. However, the present invention is not limited to this. For example, the annular member 165 is axially movable in the area of another member (for example, a chip holder) that holds the tip 161, and grips the region of the other member when the diameter of the annular member 165 decreases. May be

  In addition, the degree of elasticity (easiness of diameter reduction) of the annular member 165 can be adjusted by appropriately changing the number, size, shape, and the like of the slits 165s. The degree of elasticity (easiness of diameter reduction) of the annular member 165 can also be adjusted by changing the material and / or the thickness of the annular member 165.

  Further, the degree of elasticity (easiness of expansion and contraction) of the resin spring member 164 can be adjusted by appropriately changing the number, size, shape and the like of the slits 164s. The slits 164s preferably extend in a direction perpendicular to the axial direction, but may extend in an oblique direction (for example, in a spiral) with respect to the axial direction.

  Also, by changing the thickness of the resin spring member 164, the degree of elasticity (easiness of expansion and contraction) of the resin spring member 164 can be adjusted. Furthermore, the resin spring member 164 may be configured as a resin spring member separate from the annular member 165 (the contact surface 165t and the cylindrical portion 165a), and may be joined to the cylindrical portion 165a. In this case, also by adjusting the material of the resin spring member, the degree of elasticity (easiness of diameter reduction) of the resin spring member can be adjusted.

  Furthermore, the resin spring member 164 (or a separate resin spring member) is not limited to the form having the slit 164s, and a form having a bellows structure that can be expanded and contracted in the axial direction may be adopted.

  It is also possible to mix and use a plurality of types of replacement refills having different refill diameters (diameters of the tip 161, the tip holder 162 and / or the ink containing cylinder 163).

  Furthermore, it is also possible to use a refill that holds a friction member as the tip 161 instead of the writing material. The friction member is an eraser or a frictional heat generating rubber (erasing rubber) for a thermochromic writing instrument. In this case, it is possible to prevent the friction member from rattling at the time of handwriting erasure, and a more stable handwriting erasure feeling can be obtained.

  In the above description, as the mechanism for moving the chip holder 162 to the front end side, a mode in which the operating portion 171 of the operating body 107 is slide operated is employed, but instead, a so-called rotational delivery mechanism is employed. It may be done.

101 multi-core writing instrument 102 shaft cylinder 103 front shaft 103 t guide surface 131 opening 104 rear shaft 141 window hole 143 release bar 143 a locking wall 144 clip 105 lid 106 writing element (ballpoint)
161 chip 161a small diameter part 162 chip holder 162a small diameter part 162h fitting hole 163 ink containing cylinder part 164 resin spring member (an example of elastic member)
164s Slit 164b Rib 165 Annular member 165s Slit 165t Abutment surface 165a Cylindrical part 107 Operating body 171 Operation part 172 Front projection 173 Rear projection 174 Insertion part 175 Flange 108 Coil spring 109 Spring support

Claims (8)

An axial cylinder having an opening at the front end,
A plurality of tip holders accommodated in the barrel and movable in the axial direction of the barrel;
A tip fixed to the front end of each tip holder and capable of coming out of the opening of the cylinder with movement of the tip holder;
An annular member loosely fitted on the outer periphery of each chip or each chip holder fixed to each chip, and movable in the axial direction of the chip relative to the chip;
An elastic member connecting the chip holder and the annular member so as to be movable relative to each other;
Equipped with
At least a portion of the outer periphery of the annular member is formed with an abutment surface that abuts against a portion of the inner surface of the barrel with movement of the tip holder connected to the annular member to the front end side,
A notch is formed in a part of the annular member, and the inner diameter of the annular member is reduced when receiving a load on the contact surface,
A guide surface is formed on a part of the inner surface of the barrel, with which the contact surface abuts as the tip holder moves to the front end side,
The contact surface is adapted to receive the load from the guide surface as the tip holder connected to the annular member having the contact surface moves toward the front end. Writing instrument. A plurality of the notches are arranged at equal intervals in the circumferential direction of the annular member,
The multicore writing instrument according to claim 1, wherein each of the plurality of notches is a slit extending in the axial direction of the annular member. The abutment surface is tapered towards the front end,
The introductory writing instrument according to claim 1 or 2, wherein the guide surface is also tapered toward the front end. The multicore writing instrument according to claim 3, wherein the contact surface has a frusto-conical surface. The multi-core writing instrument according to any one of claims 1 to 4, wherein the elastic member is a cylindrical resin spring member in which a large number of slits extending in a direction perpendicular to the axial direction are formed. The multi-core writing instrument according to claim 5, wherein the annular member is integrally formed with the resin spring member. The multi-core writing instrument according to any one of claims 1 to 6, wherein one of the plurality of tip holders holds the friction member as a tip. On the rear end side of each chip holder, an operating body having an operating portion is provided,
A plurality of window holes extending in the front-rear direction are distributed in the radial direction and penetrated through the side wall of the shaft cylinder,
The operating portion of each operating body protrudes radially outward from the corresponding window hole,
Inside the shaft cylinder, there is provided a locking wall portion capable of locking a part of the operating body corresponding to the operating portion when the operating portion is slid forward,
A plurality of coil springs for urging each of the plurality of tip holders backward are provided inside the shaft cylinder,
The front end sides of the plurality of coil springs are supported by a spring support fixed to the barrel.
The multicore writing instrument according to any one of claims 1 to 7, wherein the spring support is provided with a plurality of inner holes through which the plurality of tip holders can be inserted.

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