JP2019119098A - Writing utensil - Google Patents

Abstract

To provide a writing utensil that can expose a guide pipe from a front end of a barrel longer than before.SOLUTION: A writing utensil 100 comprises: a barrel 10; a lead-delivering unit 20 supported to be relatively movable in a shaft line direction da of the barrel 10; and a guide pipe 30 supported on a front end of the barrel 10 to be movable in the shaft line direction da relatively to the barrel 10 and the lead-delivering unit 20. The lead-delivering unit 20 has a chuck support unit 27 that can move in the shaft line direction da relatively to the barrel 10; and a chuck unit 28 that can move in the shaft line direction da relatively to the chuck support unit 27. The guide pipe 30 is moved forward relatively to the barrel 10 by forward movement of the chuck unit 28 relatively to the chuck support unit 27. When the chuck unit 28 is not moved forward relatively to the chuck support unit 27, forward movement of the chuck unit 27 relatively to the barrel 10 is restricted.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a writing instrument.

  Conventionally, a core feeding unit including a shaft cylinder and a chuck supported by the shaft cylinder and holding the writing core forwardly and supported by the front end (the end on the paper surface side) of the shaft cylinder or the base; There is known a writing instrument (for example, a mechanical pencil) of a type including a guide pipe surrounding a front end area, and the guide pipe sinks into the interior of a barrel or a cap in synchronization with the wear of the writing core (e.g. Patent Document 1) ). In such a writing instrument, when the guide pipe is pressed against the paper during writing, the guide pipe is pushed rearward of the barrel by the reaction force from the paper, so the guide pipe is partially in the barrel or in the cap. Housed in

  In such a writing instrument, for example, the guide pipe is exposed from the front end of the barrel as follows. That is, the guide pipe is disposed immediately in front of the chuck, and is pushed forward by the chuck when the chuck advances with respect to the barrel when the writing core is drawn out. Thereby, the guide pipe is exposed to the outside from the front end of the barrel.

  In this case, the length by which the guide pipe is exposed to the outside from the front end of the barrel depends on the length by which the chuck advances when the writing core is drawn out. Usually, since the length of advance of the chuck is about several mm, the length in which the guide pipe can penetrate into the interior of the barrel or the cap in synchronization with the wear of the writing core is relatively short. Therefore, the user of such a writing instrument needs to frequently carry out the drawing core feeding operation (knock operation). For this reason, if the guide pipe can be exposed from the front end of the shaft cylinder longer than before, the frequency of the drawing core feeding operation can be reduced, which is convenient.

Japanese Utility Model Publication No. 7-40186

  The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a writing instrument in which the guide pipe surrounding the front end of the writing core can be exposed from the front end of the barrel longer than before.

The present invention relates to a shaft cylinder,
A core feeding unit which holds the writing core so as to be able to feed forward;
And a guide pipe provided on the front end of the shaft cylinder so as to be movable relative to the shaft cylinder and the core feeding unit in the axial direction of the shaft cylinder, and positioned on the writing core,
The core feeding unit is
A chuck support unit supported by the shaft cylinder so as to be movable relative to the shaft cylinder in the axial direction;
And a chuck unit supported by the chuck support unit so as to be movable relative to the chuck support unit in the axial direction, and holding the writing core forward.
The guide pipe moves forward relative to the shaft cylinder with relative movement of the core feeding unit forward relative to the shaft cylinder,
When the said chuck | zipper support unit is relatively moved backward with respect to the said axial cylinder, it is a writing instrument with which the relative displacement of the said axial direction of the said chuck unit with respect to the said chuck | zipper support unit is restrict | limited.

The chuck support unit is supported by the chuck support unit main body for supporting the chuck unit, and the chuck support unit main body, and the first phase and the second phase of the chuck support unit main body are supported around the axis of the barrel. Having a rotatable body between them,
The chuck unit rotates the rotating body from the second phase to the first phase when moving forward relative to the chuck support unit.
The relative movement of the chuck unit in the axial direction with respect to the chuck support unit may be restricted when the rotating body is in the first phase.

  In the above writing instrument, when the writing core is pressed rearward with respect to the barrel, the chuck unit may move relative to the barrel with respect to the rear.

The rotating body supports the chuck support unit main body so as to be relatively movable in the axial direction,
The apparatus may further include biasing means for biasing the chuck unit or the chuck support unit main body forward with respect to the rotating body or the shaft cylinder.

The chuck unit is biased rearward by a first biasing force with respect to the chuck support unit,
The chuck support unit may be biased rearward with respect to the shaft cylinder by a second biasing force larger than the first biasing force.

  Even with such a writing instrument, when the writing core is pressed rearward with respect to the barrel, the chuck unit may move relative to the barrel with respect to the rear.

The chuck support unit has a chuck support unit main body for supporting the chuck unit, and a support which is supported by the chuck support unit main body and is movable relative to the chuck support unit main body in the axial direction.
The chuck unit is biased forward with respect to the barrel or the support,
The support may be biased rearward with respect to the barrel.

  In the writing tool of the type in which the chuck unit moves relative to the barrel relative to the barrel, the chuck unit moves relative to the barrel relative to the barrel in the axial direction. It may further comprise damping means for applying a damping force corresponding to the relative velocity to the chuck unit.

  The maximum static friction force acting between the guide pipe and the shaft cylinder may be larger than the maximum static friction force acting between the guide pipe and the writing core.

Alternatively, the present invention relates to a shaft cylinder,
A chuck support unit supported by the barrel so as to be relatively movable in the axial direction of the barrel;
A chuck unit supported by the chuck support unit so as to be movable relative to the chuck support unit in the axial direction, and holding the writing core forward.
And a guide pipe provided on the front end of the shaft cylinder so as to be movable relative to the shaft cylinder, the chuck support unit, and the chuck unit in the axial direction, and a guide pipe positioned on the writing core,
When the chuck unit is moved forward relative to the barrel,
First, the chuck unit moves forward relative to the chuck support unit,
Next, it is a writing instrument in which the chuck unit, the chuck support unit, and the guide pipe move forward relative to the barrel.

  ADVANTAGE OF THE INVENTION According to this invention, the writing instrument which can expose the guide pipe which encloses the front end of a writing body longer than before conventionally from the front end of an axial cylinder can be provided.

It is a schematic longitudinal cross-sectional view which shows the writing instrument by one embodiment of this invention. It is a schematic cross-sectional perspective view which shows the rotary body of the writing instrument of FIG. It is a schematic perspective view which shows the rotation operation part of the writing instrument of FIG. It is the IV-IV line | wire cross section of the axial cylinder of the writing instrument of FIG. It is a schematic plan view which shows the rotation stop member of the writing instrument of FIG. It is a figure for demonstrating an effect | action of the writing instrument of FIG. 1, the schematic longitudinal cross-sectional view of the front area | region of the writing instrument of the state which the guide pipe was immersed in in the axial cylinder, relative positional relationship of the rotary body and rotation operation part at this time. And show. It is a figure for demonstrating an effect | action of the writing instrument of FIG. 1, and the schematic longitudinal cross-sectional view of the front area | region of the writing instrument of the state in which the drawing-out operation of writing core is performed, and the relative position of the rotary body and rotation operation part at this time. And relationship. It is a figure for demonstrating the effect | action of the writing instrument of FIG. 1, and is a schematic longitudinal cross-sectional view of the front area | region of the writing instrument in the state which the chuck unit has moved forward relative to the chuck support unit, a rotary body at this time, and rotation. The relative positional relationship of the operation part is shown. It is a figure for demonstrating the effect | action of the writing instrument of FIG. 1, The schematic longitudinal cross-sectional view of the front area | region of the writing instrument in the middle of which a chuck unit returns to an initial position after FIG. 6C, The rotary body and rotation operation part at this time And the relative positional relationship of It is a figure for demonstrating the effect | action of the writing instrument of FIG. 1, and after FIG. 6D, the schematic longitudinal cross-sectional view of the front area | region of the writing instrument of the state which the chuck | zipper unit returned to the initial position. And the relative positional relationship of It is a schematic longitudinal cross-sectional view which shows the writing instrument by the other Example of this invention. It is a schematic longitudinal cross-sectional view which shows the writing instrument by further another Example of this invention. It is a schematic longitudinal cross-sectional view which shows the writing instrument by further another Example of this invention.

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

  FIG. 1 is a schematic longitudinal sectional view showing a writing instrument 100 according to an embodiment of the present invention. Here, a mechanical pencil is illustrated as the writing instrument 100. 2 is a schematic cross-sectional perspective view showing the rotary body 42 of the writing instrument 100 of FIG. 1, and FIG. 3 is a schematic perspective view showing the rotation operation unit 41 of the writing instrument 100 of FIG. 1. 4 is a cross-sectional view of the barrel 10 of the writing instrument 100 of FIG. 1 taken along line IV-IV, and FIG. 5 is a schematic plan view showing the rotation stopping member 60 of the writing instrument 100 of FIG.

  As shown in FIG. 1, the writing instrument 100 is supported by the barrel 10 and the barrel 10, and the core feeding unit 20 holds the writing core 21 forwardly (leftward in FIG. 1) so as to be able to be delivered. And a guide pipe 30 positioned on the writing core 21. The core feeding unit 20 is supported by the barrel 10 so as to be relatively movable in the axial direction da of the barrel 10. The guide pipe 30 is supported so as to be movable relative to the barrel 10 and the core feeding unit 20 in the axial direction da of the barrel 10.

  The core feeding unit 20 according to the present embodiment is movable relative to the chuck support unit 27 in the axial direction da with respect to the chuck support unit 27 supported by the shaft cylinder 10 so as to be movable relative to the cylinder 10 in the axial direction da. And a chuck unit 28 supported by the chuck support unit 27 and holding the writing core 21 forward. The guide pipe 30 is configured to move forward relative to the barrel 10 as the core delivery unit 20 moves relative to the barrel 10 in the forward direction.

  As shown in FIG. 1, the chuck support unit 27 is supported by the chuck support unit main body 29 for supporting the chuck unit 28 and the chuck support unit main body 29, and the axis L of the barrel 10 with respect to the chuck support unit main body 29. And a rotating body 42 rotatable around the first phase and the second phase. The first phase and the second phase will be described later. The chuck support unit main body 29 of the present embodiment is supported by an outer cylinder 29p, a front end region of the outer cylinder 29p, and a tightening ring 25 for tightening a chuck 24 described later and attaching a chuck unit 28 to the rear with respect to the outer cylinder 29p. And a return spring 26 for biasing.

  Furthermore, the writing instrument 100 has biasing means 44 for biasing the chuck support unit 27 rearward with respect to the barrel 10. The biasing means 44 of the present embodiment is a coil spring and is arranged as follows. That is, the outer cylinder 29p of the chuck support unit 27 has a flange portion 27f on the outer surface. Furthermore, the barrel 10 has an inner flange 10p in front of the flange portion 27f. The biasing means 44 is disposed between the flange portion 27f and the inner weir 10p. In the chuck support unit 27 of the present embodiment, the relative movement to the rear with respect to the barrel 10 is restricted by the small diameter portion 10 s provided on the inner surface of the barrel 10. Then, in this state, the flange portion 27 f and the inner flange 10 p are provided in a positional relationship in which the separation distance in the axial direction da is smaller than the natural length of the biasing means 44 and mutually provided. For this reason, the biasing means 44 is disposed in a compressed state between the flange portion 27f and the inner weir 10p. The biasing means may bias the chuck unit 28 or the chuck support unit main body 29 forward with respect to the rotating body 42.

  The outer cylinder 29p has a reduced diameter portion 27p on the front inner peripheral surface. The chuck 24 is disposed so as to penetrate the opening defined by the reduced diameter portion 27p in the axial direction da, and is movable relative to the outer cylinder 29p in the axial direction da. The return spring 26 is disposed in a compressed state between the reduced diameter portion 27 p of the outer cylinder 29 p and the front end of the rotation operation portion 41. With such a configuration, the return spring 26 biases the chuck unit 28 rearward with respect to the outer cylinder 29p. When the chuck unit 28 is not moved forward relative to the chuck support unit 27, the chuck 24 clamps the writing core 21 so that the front end region is tightened by the tightening ring 25.

  As shown in FIG. 1, the chuck unit 28 has a chuck 24 for holding the writing core 21 and a core pipe 23 connected to the rear end of the chuck 24 and accommodating the writing core 21. The chuck 24 is made of, for example, brass, and the core pipe 23 is made of, for example, polypropylene. Furthermore, the chuck unit 28 rotates the rotating body 42 from the second phase to the first phase when moving relative to the chuck support unit 27 in the rear region of the chuck 24 (see FIG. 3). See). In the present embodiment, as shown in FIGS. 1 and 3, the chuck 24 and the rotation operation unit 41 are configured as separate members, but the present invention is not limited to such a configuration. For example, in another example, the rotation operation unit 41 may be integrally provided to the chuck 24 and / or the core pipe 23.

  Furthermore, as shown in FIG. 1 and FIG. 4, the groove 13 extending in the axial direction da is formed on the inner surface of the portion surrounding the rotating body 42 in the barrel 10. The four grooves 13 of the present embodiment are provided at equal intervals along the circumferential direction ds of the barrel 10. The groove 13 is for permitting relative movement of the rotary body 42 forward with respect to the barrel 10 only when the rotary body 42 has a specific phase (first phase). Further, as shown in FIG. 4, in the portion of the barrel 10 in which the groove 13 is formed, the inner diameter d1 of the rear region is larger than the inner diameter d2 of the front region.

  In the writing instrument 100 according to the present embodiment, the relative movement of the chuck unit 28 in the axial direction da with respect to the chuck support unit 27 is restricted when the chuck support unit 27 moves relative to the barrel 10 rearward. It has become. Such limitation is realized in cooperation with the rotating body 42, the rotation operation unit 41 and the barrel 10. Hereinafter, specific configurations of these components will be described.

  The rotating body 42 has a substantially cylindrical shape. However, FIG. 2 shows only the back side portion of the rotating body 42 as a longitudinal sectional view. As shown in FIG. 2, the rotating body 42 has a guided portion 42 g configured as a convex portion on the outer surface. A total of four guided portions 42g are provided, two in the far side shown in FIG. 2 and two in the near side not shown in FIG. In other embodiments, three or less, or five or more guided portions 42g may be provided. The four guided portions 42g have the same shape as each other, and have dimensions that can be accommodated in the groove 13 provided in the shaft cylinder 10. The four guided portions 42 g are arranged at equal intervals in the circumferential direction ds of the rotating body 42. The outer diameter of the rotating body 42 is maximum at the phase where the guided portion 42g is provided. This largest outside diameter is larger than d2 and smaller than d1. On the other hand, the outer diameter of the rotating body 42 in the phase where the guided portion 42g is not provided is smaller than d2.

  Furthermore, the rotating body 42 has a raised portion 42e on the inner surface. The number of the protuberances 42 e is two in total, one in the far side shown in FIG. 2 and one in the near side not shown in FIG. 2. The two protuberances 42 e are arranged with a phase difference of 180 ° in the circumferential direction ds of the barrel 10. Each raised portion 42e has a first inclined edge 42e1 at an edge on the clockwise side as viewed from the rear and a second inclined edge 42e2 at the opposite edge. As shown in FIG. 2, the first inclined edge 42 e 1 is an edge inclined with respect to the axial direction da of the barrel 10 so as to face the rear, and the second inclined edge 42 e 2 is an axis so as to face the front. The edge portion is inclined with respect to the axial direction da of the cylinder 10.

  Next, the rotation operation unit 41 will be described. As shown in FIG. 3, the rotation operation unit 41 has a substantially cylindrical shape. A chuck fitting portion (not shown) externally fitted to the rear end of the chuck 24 is provided at the front end (left lower end in FIG. 3) of the rotation operation portion 41. Further, at the rear end (upper right end in FIG. 3) of the rotation operation portion 41, a core pipe fitting portion 41s fitted inside the core pipe 23 is provided. Furthermore, as shown in FIG. 3, a protrusion for applying a force in the circumferential direction ds to the rotary body 42 is formed on the outer surface of the rotation operation unit 41. The projection corresponds to a first projection 41 a having a first tapered portion 41 at corresponding to a first inclined edge 42 e 1 of the rotating body 42 at its front end, and a second taper corresponding to a second inclined edge 42 e 2 of the rotating body 42. The portion 41 bt has a second protrusion 41 b formed at the rear end. In the present embodiment, the first protrusions 41 a and the second protrusions 41 b are alternately arranged at equal intervals in the circumferential direction ds, corresponding to the raised portions 42 e of the rotating body 42.

  Furthermore, the writing instrument 100 has a rotation stop member 60 that prevents relative rotation around the axis L with respect to the barrel 10 of the rotation operation unit 41. As shown in FIG. 5, the rotation stopping member 60 has a substantially ring shape, and four engaging convex portions 63 corresponding to the grooves 13 of the barrel 10 are formed on the outer surface. Furthermore, as for the rotation stopping member 60, four engagement recessed parts 62 are formed in the inner surface of the position in which the engagement convex part 63 is formed in the outer surface. The two engaging recesses 62 are arranged such that two opposing ones engage with the first projections 41 a of the rotary operation unit.

  As shown in FIG. 1, the rotary body 42 and the rotation stop member 60 are disposed in the barrel 10 so as to surround the rotation operation portion 41. The rotary body 42 is disposed in a second phase in which the guided portion 42g is at a position different from the position of the groove 13 of the barrel 10 when viewed in the axial direction da. Further, the rotation stopping member 60 is disposed in the first phase in which the four engagement convex portions 63 are at the same position as the position of the groove 13 of the barrel 10. More specifically, the to-be-guided part 42g of the rotary body 42 is located in the back area | region which has the internal diameter d1 among the parts of the axial cylinder 10 in which the groove | channel 13 is formed. As described above, since the inner diameter d1 is larger than the maximum value of the outer diameter of the rotating body 42, the rotating body 42 can rotate relative to the barrel 10 around the axis L of the barrel 10. On the other hand, as described above, the maximum value of the outer diameter of the rotating body 42 is larger than the inner diameter d2 of the rear region of the portion of the barrel 10 in which the groove 13 is formed. For this reason, relative movement forward of the rotating body 42 with respect to the barrel 10 is prohibited. Further, in the rotation stopping member 60, the four engaging convex portions 63 are fitted into the groove 13 of the barrel 10 at the rear of the rotating body 42, and relative rotation around the axis L with respect to the barrel 10 is prohibited. ing. The rotating body 42 and the rotation stopping member 60 press the small diameter portion 10 s of the barrel 10 rearward by the biasing force of the biasing means 44.

  Returning to FIG. 1, the guide pipe 30 of the present embodiment will be described. The guide pipe 30 is supported by the front end 11 of the barrel 10, supports the guide pipe main body 31 and the guide pipe main body 31 in the rear end region, and can slide the inner surface of the barrel 10 in the axial direction da. And a support portion 32. Further, the barrel 10 defines a housing space 33 for housing the sliding support portion 32. The housing space 33 has a predetermined length in the axial direction da, and the sliding support portion 32 slides in the housing space 33 in the axial direction da within the range of this length. .

  Furthermore, as shown in FIG. 1, the barrel 10 has a friction portion 14 on the inner surface of the front end 11 to provide a predetermined coefficient of static friction with the outer surface of the guide pipe 30. The friction part 14 of the present embodiment is an O-ring. Of course, if a predetermined static friction coefficient can be provided, appropriate means such as controlling the surface roughness of the inner surface of the front end of the barrel 10 can be exerted. The guide pipe 30 is configured to be positioned immediately in front of the chuck 24 in a state in which the guide pipe 30 is immersed in the barrel 10.

  The maximum static friction force acting on the contact portion A between the sliding support portion 32 of the guide pipe 30 and the barrel 10 defining the housing space 33 is fA, and the contact portion B between the guide pipe main body 31 and the writing core 21 acts. Assuming that the maximum static friction to be performed is fB, a relationship of fA> fB is established between the static frictions fA and fB. Therefore, as described later, when the writing core 21 passes through the inside of the guide pipe main body 31 in the axial direction da, the sliding support portion 32 maintains the stationary state with respect to the barrel 10 There is.

  The core feeding unit 20 further includes a pressing operation unit 18 attached to the rear end of the core pipe 23. The writing core 21 is drawn out from the chuck unit 28 by pressing the knocking operation unit 18 (knocking operation). The specific delivery mode will be described later. The pressing operation unit 18 of the present embodiment is made of POM resin. The pressing operation portion 18 is configured as a holder portion 18 h which holds the eraser 80 at the rear so as to be removable. A dome-shaped knob 81 covering the rear of the eraser 80 is externally fitted to the holder portion 18 h so as to be removable.

  Next, the operation of the writing instrument 100 as described above will be described with reference to FIGS. 6A to 6E. FIG. 6A is a view showing the writing instrument 100 in a state in which the guide pipe 30 is immersed in the barrel 10, and FIG. 6B is a view showing the writing instrument 100 in a state in which the drawing core 21 is drawn out. FIG. 6C is a view showing the writing instrument 100 in a state in which the chuck unit 28 is moved relative to the chuck support unit 27 forward, and FIG. 6D is in the middle of returning the chuck unit 28 to the initial position after FIG. 6C. 6E is a view showing the writing instrument 100, and FIG. 6E is a view showing the writing instrument 100 in a state where the chuck unit 28 has returned to the initial position after FIG. 6D. In each of the drawings, the left side is a schematic longitudinal sectional view showing the front area of the writing instrument 100, and the right side is a diagram showing the relative positional relationship between the rotating body 42 and the rotation operation unit 41. However, for the convenience of explanation, the rotary operation member is shown in a front view in the left view. In the following description, FIG. 6A in which the guide pipe main body 31 is embedded in the barrel 10 is taken as an initial state.

  First, the feeding of the writing core 21 by a normal knock operation will be described. Hereinafter, this knocking operation is referred to as a first knocking operation. Prior to writing on the paper surface, the pressing operation unit 18 is removed from the core pipe 23 and the writing core 21 is inserted into the core pipe 23 as necessary. Thereafter, the pressing operation unit 18 is attached to the core pipe 23 again. In this state, the pressing operation portion 18 (knob 81) is pushed forward (knocked) with respect to the barrel 10 in a posture in which the front end 11 of the barrel 10 is positioned below the pressing operation portion 18. As a result, the chuck unit 28 is advanced with respect to the chuck support unit 27 against the biasing force of the return spring 26. In the process of this advancement, the clamp ring 25 is disengaged from the chuck 24 and the chuck 24 is released. As a result, the writing core 21 is drawn forward from the chuck 24 by a predetermined length.

  At the time of this knocking, the chuck 24 advances inside the accommodation space 33, and the sliding support portion 32 of the guide pipe 30 is pushed forward by the chuck 24. Thereby, the guide pipe 30 is moved relative to the barrel 10 in the forward direction. As a result, the guide pipe main body 31 is exposed from the front end 11 of the barrel 10. And this exposed state is maintained by the frictional force which acts on the contact part A (refer FIG. 1) of the sliding support part 32 of the guide pipe 30, and the axial cylinder 10 which defines the accommodation space 33. As shown in FIG.

  Then, when the pushing operation unit 18 is not pushed forward, the chuck unit 28 moves relative to the chuck support unit 27 rearward by the biasing force of the return spring 26. Along with this, the chuck 24 is tightened by the tightening ring 25. As a result, the writing core 21 is held by the chuck 24 and the state in which the writing core 21 is drawn out is maintained.

  The operations of the rotating body 42 and the rotation operation unit 41 in the above first knocking operation are as follows. That is, when the pressing operation unit 18 is pushed forward with respect to the barrel 10, the rotation operating unit 41 moves relative to the rotating body 42 forward. The rotation operation portion 41 goes straight in the axial direction da without rotating around the axis L of the barrel 10 due to the presence of the rotation stopping member 60. Then, when the chuck unit 28 moves relative to the chuck support unit 27 most forward, the first tapered portion 41 at of the first protrusion 41 a of the rotation operation portion 41 just contacts the first inclined edge 42 e 1 of the rotating body 42. Contact (see FIG. 6B). Then, when the pressing of the pressing operation portion 18 is released, the chuck unit 28 is moved rearward relative to the chuck supporting unit 27 by the biasing force of the return spring 26, and the initial state is restored (see FIG. 6A).

  The above first knocking operation is repeated until the writing core 21 is slightly exposed from the front end of the guide pipe main body 31 (see FIG. 1). As described above, the maximum static friction force fA acting on the contact portion A between the slide support portion 32 of the guide pipe 30 and the axial cylinder 10 defining the accommodation space 33 is the guide pipe main body 31 and the writing core 21 larger than the maximum static friction force fB acting on the contact portion B with 21. Therefore, when the writing core 21 is drawn out, the guide pipe 30 is not engaged with the writing core 21 and does not advance further from the front end 11 of the barrel 10.

  Then, the user holds the barrel 10, and while the writing core 21 is in contact with the paper surface, the barrel 10 is moved as desired to perform writing. Along with writing, the writing core 21 wears, and the length of the writing core 21 exposed from the front end of the guide pipe 30 gradually decreases. When the writing core 21 further wears, the front end of the guide pipe 30 abuts on the paper surface. Even in such a case, writing can be continued without further drawing out the writing core 21 by the guide pipe 30 diving into the barrel 10 in synchronization with the wear of the writing core 21.

  By the way, in the writing instrument 100 according to the present embodiment, the guide pipe 30 can be exposed longer from the front end 11 of the barrel 10 by pressing the pressing portion 18 harder than in the first knock operation. Such a knocking operation is hereinafter referred to as a second knocking operation. The action of the writing instrument 100 at the time of the second knock operation will be described below.

  When the pressing operation portion 18 is strongly pushed forward with respect to the barrel 10, in the state shown in FIG. 6B, the first projection 41a of the rotation operating portion 41 presses the first inclined edge portion 42e1 of the rotating body 42 forward. Do. By this, by this pressing, mutually opposing forces act on the circumference of the axis L between the rotating body 42 and the rotation operation unit 41. By the way, as described above, the rotation stop portion 60 prohibits the relative rotation around the axis L with respect to the barrel 10 by the rotation stopping member 60. For this reason, the rotation operation part 41 goes straight along the axial direction da without rotating relative to the barrel 10. For this reason, as shown in FIG. 6 c, the rotary body 42 is rotated counterclockwise relative to the barrel 10 as viewed from the rear (as viewed from the right in FIG. 6C). By this relative rotation, the phase of the rotating body 42 changes from the second phase in the initial state to the first phase. That is, the phase of the rotating body 42 around the axis L coincides with the phase of the groove 13 of the barrel 10. As a result, the rotary body 42 is allowed to move relative to the barrel 10 in the forward direction. As a result, the chuck unit 28 and the chuck support unit 27 move forward relative to the barrel 10 while compressing the biasing means 44 by the strong pressing force acting on the pressing operation portion 18.

  The pressing operation of the pressing operation portion 18 can be performed until the sliding support portion 32 of the guide pipe 30 abuts on the front end in the accommodation space 33. Thereby, the guide pipe main body 31 is exposed from the front end 11 of the barrel 10 beyond the length exposed from the front end 11 of the barrel 10 by the first knocking operation (see FIG. 6C). At this time, as shown in FIG. 6C, the rotary body 42 is positioned such that the second inclined edge 42e2 of the raised portion 42e faces the second tapered portion 41bt of the second projection 41b of the rotation operation portion 41.

  Then, when the pressing force on the pressing operation portion 18 is released or weakened, as shown in FIG. 6D, the chuck support unit 27 and the chuck unit 28 move against the barrel 10 by the biasing force of the biasing means 44. And moved backward. The rotating body 42 maintains the first phase until the chuck support unit 27 is returned to the initial position by the presence of the groove 13 of the barrel 10. During this time, the relative movement of the chuck unit 28 with respect to the chuck support unit 27 in the axial direction da, specifically the relative movement to the rear, is restricted.

  When the chuck support unit 27 returns to the initial position, the rotary body 42 can rotate relative to the barrel 10 about the axis L. In this state, when the rotation operation unit 41 not rotating relative to the shaft cylinder 10 moves relative to the rotating body 42 relative to the rotating body 42, the second tapered portion 41 bt of the second projection 41 b of the rotation operating unit 41 2 Press the inclined edge 42e2 backward. By this, the rotating body 42 is rotated clockwise around the axis L as viewed from the rear. Then, when the second tapered portion 41bt of the rotation operation portion 41 is removed from the second inclined edge 42e2 of the rotation body 42, the rotation of the rotation body 42 is finished, and the rotation operation portion 41 is further rearward with respect to the chuck support unit 27. The relative movement restores the initial state (see FIG. 6E).

  Then, as described above, the user holds the barrel 10 and writing is performed on the paper surface. When the writing core 21 wears, the front end of the guide pipe 30 eventually abuts on the surface of the sheet, but the guide pipe 30 sinks into the barrel 10 in synchronization with the wear. Therefore, writing can be continued without additionally drawing out the writing core 21 until the slide support portion 32 of the guide pipe 30 abuts on the rear end of the accommodation space 33 of the barrel 10.

  In summary, when the chuck unit 28 is moved forward relative to the barrel 10, the chuck unit 28 and the guide pipe 30 move forward relative to the chuck support unit 27. Next, the chuck unit 28, the chuck support unit 27, and the guide pipe 30 move relative to the barrel 10 in the forward direction.

  According to the present embodiment as described above, it is possible to provide the writing instrument 100 in which the guide pipe 30 surrounding the front end of the writing core 21 can be exposed from the front end 11 of the barrel 10 longer than before. For this reason, it is possible to write more by one knock operation (second knock operation).

  Moreover, the writing instrument 100 has a difference of the inner diameter provided in the rotary body 42 provided in the chuck support unit 27 and the groove 13 provided in the shaft cylinder 10 and the shaft cylinder 10 provided with the groove 13 ( d1> d2), and a rotation operation unit 41 provided in the chuck unit 28 for rotating the rotating body 42 relative to the chuck support unit main body between the first phase and the second phase. These components cooperate to limit the relative movement of the chuck unit 28 in the axial direction da with respect to the chuck support unit 27 when the rotating body 42 is in the first phase. As a result, since the chuck support unit 27 does not move relative to the barrel 10 during the first knock operation, the first knock operation can be performed stably.

  Next, the modification of the above writing instrument 100 is demonstrated.

  FIG. 7 is a schematic longitudinal sectional view showing a writing instrument 200 according to a modification of FIG. The writing instrument 200 is different from the writing instrument 100 shown in FIG. 1 in that the chuck unit 228 does not have a rotational operation unit and the chuck support unit 227 does not have a rotating body. Further, the chuck unit 228 of the writing instrument 200 is biased rearward by the return spring 26 with respect to the chuck support unit 227 by the first biasing force. The chuck support unit 227 of the writing instrument 200 is biased rearward with respect to the barrel 10 by the biasing means 44 with a second biasing force larger than the first biasing force. In particular, the second biasing force is set larger than the biasing force generated by the return spring 26 when the return spring 26 is most compressed at the time of the knocking operation of the writing instrument 200 by the first knocking operation. The other configuration is substantially the same as that of the writing instrument 100 shown in FIG. Therefore, in FIG. 7, the same components as in FIG. 1 will be assigned the same reference numerals, and detailed descriptions thereof will be omitted.

  In the writing instrument 200 as described above, the chuck unit 228 is advanced with respect to the chuck support unit 227 against the biasing force of the return spring 26 during the first knocking operation. Similar to the writing instrument 100 shown in FIG. 1, in the process of this advancement, the clamp ring 25 is disengaged from the chuck 24 and the chuck 24 is released. At the same time, the slide support portion 32 of the guide pipe 30 is pushed forward by the chuck 24, and the guide pipe 30 is exposed from the front end 11 of the barrel 10. Meanwhile, the force acting on the biasing means 44 from the chuck support unit 227 does not exceed the biasing force of the biasing means 44. For this reason, the chuck support unit 227 does not move relative to the barrel 10 during the first knock operation.

  At the time of the second knocking operation, the pressing operation portion 18 is pressed forward by a force that exceeds the combined force of the biasing force of the return spring 26 and the biasing force of the biasing means 44. As a result, the biasing means 44 is compressed, and the chuck support unit 227 and the chuck unit 228 are moved relative to the barrel 10 in the forward direction. The relative movement further exposes the guide pipe 30 from the front end 11 of the barrel 10.

  Then, when the pressing of the pressing operation portion 18 is released, the chuck support unit 227 and the chuck unit 228 are relatively moved rearward with respect to the barrel 10 by the biasing force of the biasing unit 44. Further, the chuck unit 228 is moved rearward relative to the chuck support unit 227 by the biasing force of the return spring 26.

  The operation of the writing instrument 200 as described above is basically the same as the operation of the writing instrument 100 shown in FIG. 1. When the chuck unit 228 is moved forward relative to the barrel 10, first, the chuck unit 228 and the guide pipe 30 Is moved forward relative to the chuck support unit 227, and then the chuck unit 228, chuck support unit 227 and guide pipe 30 are moved forward relative to the barrel 10.

  Also according to the above-described modification, it is possible to provide the writing instrument 200 which can expose the guide pipe 30 surrounding the front end of the writing core 21 from the front end 11 of the shaft cylinder 10 longer than before. That is, also according to this modification, it is possible to provide the writing instrument 200 capable of performing more writing by one knock operation.

  Further, the chuck unit 228 is urged rearward with respect to the chuck support unit 227 by the first urging force, and the chuck support unit 227 is driven by the shaft cylinder 10 with the second urging force larger than the first urging force. It is biased to the rear against. As a result, since the chuck support unit 227 does not move relative to the barrel 10 during the first knock operation, the first knock operation can be performed stably.

  Next, a further modified example of the writing instrument 100 shown in FIG. 1 will be described.

  FIG. 8 is a schematic longitudinal sectional view showing a writing instrument 300 according to a further modification of FIG. In the writing instrument 300, when the writing core 21 is pressed backward with respect to the barrel 10, the chuck unit 328 is moved relative to the barrel 10 with respect to the rear. Specifically, the rotating body 342 supports the chuck support unit main body 329 so as to be relatively movable in the axial direction da. Furthermore, the writing instrument 300 has a coil spring 340 as biasing means for biasing the chuck unit 328 forward with respect to the rotating body 342. Attenuating means 350 is provided behind the coil spring 340 (rightward in FIG. 1) to apply a damping force to the chuck unit 328 in accordance with the relative speed of the chuck unit 328 with respect to the barrel 10. The damping means 350 is fixed to the barrel 10.

  As shown in FIG. 8, the chuck unit 328 has a cylindrical member 322 for limiting the amount of relative movement of the chuck unit 328 to the rear with respect to the rotating body 342. The outer periphery of the cylindrical member 322 is surrounded by the rotating body 342.

  Next, the damping means 350 has a cylindrical housing 351 surrounding the core pipe 23 of the chuck unit 328, and two seal portions 352a and 352b disposed in the gap between the housing 351 and the core pipe 23. There is. The seal portions 352a and 352b in the present embodiment are O-rings, which are arranged at intervals in the axial direction da, and seals the gap between the housing 351 and the core pipe 23 all around the core pipe 23. As shown in FIG. 8, a spiral groove is formed on the inner surface 351s of the housing 351, and the space from the inner surface 351s to the outer surface of the core pipe 23 is sealed by the two sealing portions 352a and 352b. In the axial direction da. Then, the sealed space is filled with grease 353.

  The coil spring 340 is disposed between the flange portion 27 f of the chuck support unit 27 and the abutted portion 345 provided on the rotating body 342 in an expandable and compressible state. Due to the biasing force of the coil spring 340, the chuck unit 328 is positioned at the front of the movable range with respect to the rotating body 342. At this time, a gap g of, for example, 0.5 mm is formed between the rear end of the cylindrical member 322 and the abutted portion 345. The coil spring 340 may be configured to bias the chuck unit 328 forward with respect to the barrel 10. The other configuration is substantially the same as that of the writing instrument 100 shown in FIG. For this reason, in FIG. 8, the same code | symbol is attached | subjected to the same component as the writing instrument 100 of FIG. 1, and the detailed description is abbreviate | omitted.

  In the writing instrument 300 as described above, the writing core 21 is moved backward with respect to the axial cylinder 10 and the guide pipe 30 by pressing the axial cylinder 10 toward the surface of the paper with the front end of the writing core 21 in contact with the surface of the paper. It can be moved relative to it. That is, the pressing force is transmitted from the writing core 21 to the coil spring 340 via the chuck unit 328. When the transmitted force exceeds the initial movement load of the coil spring 340, the coil spring 340 is compressed, and the chuck unit 328 and the chuck support unit 327 move relative to the barrel 10 rearward. The movement distance of this relative movement is defined by the gap g between the rear end of the cylindrical member 322 and the abutted portion 345. Therefore, in the example shown in FIG. 8, it is 0.5 mm.

  As understood from the relationship between the maximum static friction force fA and the maximum static friction force fB described above, when the writing core 21 moves relative to the barrel 10 rearward with respect to the barrel 10, the guide pipe 30 is engaged with the writing core 21 and the shaft It does not move relative to the cylinder 10 rearward. However, since the guide pipe 30 is also pressed from the paper surface after the writing core 21 completely dives into the guide pipe 30, it moves relative to the barrel 10 backward. That is, the length of the portion of the guide pipe main body 31 exposed from the front end of the barrel 10 decreases. In the process of such relative movement, the chuck unit 328 is subjected to a damping force corresponding to the relative movement speed by the damping means 350. The damping force provides the user of the writing instrument 300 with a suitable sense of resistance.

  Then, when the pressing force on the writing core 21 is released, or when the pressing force is reduced until the initial movement load of the coil spring 340 is reduced, the coil spring 340 expands to make the cylindrical member 322 relative to the barrel 10 forward. Move it. This relative movement ends when the chuck unit 328 is moved to the rear end of the movable range with respect to the rotating body 342. As a result, the relative positional relationship between the barrel 10 and the chuck unit 328 is restored to the initial state (see FIG. 8). At this time, the damping means 350 acts on the chuck unit 328 according to the relative velocity with respect to the barrel 10. For this reason, even if the pressing force is instantaneously removed from the writing core 21, the chuck unit 328 slowly advances with respect to the barrel 10. That is, the chuck unit 328 smoothly moves relative to the barrel 10.

  Also at this time, as understood from the relationship between the maximum static friction force fA and the maximum static friction force fB described above, the guide pipe 30 is engaged with the writing core 21 and moves forward relative to the barrel 10. There is no such thing. That is, while the chuck unit 328 is moved forward relative to the barrel 10, the guide pipe 30 maintains the relative position with respect to the barrel 10. The relative reciprocating movement of the chuck unit 328 with respect to the barrel 10 as described above increases the length of the writing core 21 exposed from the front end of the guide pipe 30 by the amount by which the guide pipe 30 retreats with respect to the barrel 10. Do.

  Alternatively, the relative reciprocating movement of the chuck unit 328 with respect to the barrel 10 as described above also provides the function of reducing breakage of the writing core 21. That is, when an excessive writing pressure acts on the writing core 21 during writing, the component (component force) of the writing pressure along the axial direction da of the barrel 10 causes the coil spring 340 to be compressed. Thereby, since the writing core 21 sinks into the guide pipe 30, breakage of the writing core 21 is effectively avoided. Then, when the writing pressure is weakened, the relative positional relationship between the writing core 21 and the barrel 10 is restored by the biasing force of the coil spring 340.

  According to the present modification as described above, the length of the writing core 21 exposed from the front end of the guide pipe 30 can be increased regardless of the knocking operation of the pressing operation unit 18. For this reason, since it is possible to realize a state in which the guide pipe 30 does not abut on the sheet at the time of writing regardless of the knocking operation, it is possible to provide the writing instrument 300 having high convenience and smooth writing comfort. Furthermore, since the writing core 21 is drawn into the guide pipe 30 when the writing pressure acting on the writing core 21 is increased, the application of an excessive writing pressure on the writing core 21 is suppressed. Thereby, the writing instrument 300 capable of effectively suppressing breakage of the writing core 21 can be provided.

  Furthermore, since it is easy to maintain the state in which the writing core 21 is slightly exposed from the front end of the guide pipe 30, the visibility of the writing core 21 is good. For this reason, it is effectively suppressed that the user of the writing instrument 300 draws the writing core 21 excessively from the front end of the guide pipe 30 without intention and writing is effectively suppressed, so breakage of the writing core 21 is effectively suppressed. obtain.

  Further, the movable range of the chuck unit 328 with respect to the rotating body 342 is defined by the gap g between the abutted portion 345 of the rotating body 342 and the cylindrical member 322. Therefore, the amount of retraction of the chuck unit 328 with respect to the rotating body 342 can be reliably regulated within an appropriate range.

  Further, a damping means 350 is disposed between the barrel 10 and the chuck unit 328 to cause the core pipe 23 to have a damping force according to the relative speed of the chuck unit 328 with respect to the barrel 10. Therefore, the relative movement of the writing core 21 with respect to the barrel 10 can be made smooth. Furthermore, the operation feeling of the knocking operation at the time of feeding out the writing core 21 can also be improved.

  The damping means 350 has a cylindrical housing 351 surrounding the core pipe 23 and is disposed at an interval in the axial direction da in the gap between the housing 351 and the core pipe 23 and seals the gap over the entire circumference of the core pipe 23 And two seal portions 352a and 352b. The grease 353 is filled in the space sealed by the two seal portions 352 a and 352 b in the housing 351. Therefore, the effect of the damping means 350 can be sustained for a long time, and the surrounding members are not contaminated with the grease 353.

  Furthermore, since the spiral groove is formed on the inner surface 351s of the housing 351, the grease 353 can be suitably held, and a stable damping force can be provided to the core pipe 23.

  Further, since the coil spring 340 and the damping means 350 are arranged in series in the axial direction da of the barrel 10, the coil spring 340 and the damping means 350 can be accommodated in the barrel 10 without increasing the diameter of the barrel 10. It can be arranged.

  The damping means 350 and the coil spring 340 as described above may be additionally provided to the writing instrument 200 shown in FIG. FIG. 9 is a schematic longitudinal sectional view showing such a writing instrument 400. As shown in FIG. As shown in FIG. 9, in the writing instrument 400, the chuck support unit 427 is supported by the chuck support unit body 429 supporting the chuck unit 428 and the chuck support unit body 429, and in the axial direction da with respect to the chuck support unit body 429. And a relatively movable support 427 s. The chuck unit 428 is biased forward with respect to the barrel 10 and the support 427 s by the biasing force of the return spring 26, and the support 427 s is biased rearward with respect to the barrel 10 by the biasing means 44. There is. The other configuration is the same as that of the writing instrument 200 shown in FIG. For this reason, in FIG. 9, the same reference numerals are given to the same components as those of the writing instrument 200 of FIG. 7, and the detailed description thereof will be omitted.

  Also in such a writing instrument 400, the same action as the writing instrument 200 shown in FIG. 7 is provided, and furthermore, the drawing in of the writing core 21 similar to the writing instrument 300 shown in FIG. 8 is realized. Therefore, according to the writing instrument 400, the same effect as that of the writing instrument 200 shown in FIG. 7 can be exhibited, and in the writing instrument 300 shown in FIG. And the effect of reducing breakage of the writing core 21 may be provided.

  In addition, in the writing instrument 300,400 shown in FIG.8 and FIG.9, the structure which removed the attenuation means 320,450 is also possible. In this case, the chuck units 328 and 428 do not receive a damping force according to the relative moving speed with respect to the barrel 10. Therefore, rapid operation can be provided during knocking operation or when the chuck units 328, 428 move relative to the rotating body 342 or the support 427s by compression and extension of the coil springs 340, 440.

Reference Signs List 10 shaft cylinder 10p inner diameter 10s small diameter portion 11 front end 13 groove 14 friction portion 18 pressing operation portion 18h holder portion 20 core feeding unit 21 writing core 23 core pipe 24 chuck 25 clamping ring 26 return spring 27 chuck support unit 27f flange portion 27p Diameter portion 28 Chuck unit 29 Chuck support unit main body 29p Outer cylinder 30 Guide pipe 31 Guide pipe main body 32 Sliding support portion 33 Housing space 40 Coil spring 41 Rotation operating portion 41a First projection 41at First taper portion 41b Second projection 41bt Second Tapered portion 41s Core pipe fitting portion 42 Rotating body 42e Protrusive portion 42e1 First inclined edge portion 42e2 Second inclined edge portion 42g Guided portion 44 Biasing means 60 Rotation stop member 62 engagement concave portion 63 engagement convex portion 80 Eraser 81 Knob 100 Writing instrument 200 Writing instrument 22 Chuck support unit 228 Chuck unit 300 Writing tool 320 Damping means 322 Tubular member 322 f Locking part 327 Chuck support unit 328 Chuck unit 329 Chuck support unit main body 340 Coil spring 342 Rotating body 345 Contacted part 350 Damping means 351 Housing 351s Inner surface 352a Seal Part 352b Sealed part 353 Grease 400 Writing implement 427 Chuck support unit 427s Support 428 Chuck unit 429 Chuck support unit main body 440 Coil spring 450 Damping means

Claims (10)

With a cylinder,
A core feeding unit which holds the writing core so as to be able to feed forward;
And a guide pipe provided on the front end of the shaft cylinder so as to be movable relative to the shaft cylinder and the core feeding unit in the axial direction of the shaft cylinder, and positioned on the writing core,
The core feeding unit is
A chuck support unit supported by the shaft cylinder so as to be movable relative to the shaft cylinder in the axial direction;
And a chuck unit supported by the chuck support unit so as to be movable relative to the chuck support unit in the axial direction, and holding the writing core forward.
The guide pipe moves forward relative to the shaft cylinder with relative movement of the core feeding unit forward relative to the shaft cylinder,
The writing instrument, wherein the relative movement of the chuck unit in the axial direction with respect to the chuck support unit is restricted when the chuck support unit is moved backward relative to the barrel. The chuck support unit is supported by the chuck support unit main body for supporting the chuck unit, and the chuck support unit main body, and the first phase and the second phase of the chuck support unit main body are supported around the axis of the barrel. Having a rotatable body between them,
The chuck unit rotates the rotating body from the second phase to the first phase when moving forward relative to the chuck support unit.
The writing instrument according to claim 1, wherein the chuck unit is restricted in the relative movement in the axial direction with respect to the chuck support unit when the rotating body is in the first phase.   The writing instrument according to claim 2, wherein when the writing core is pressed rearward with respect to the barrel, the chuck unit moves relative to the barrel back. The rotating body supports the chuck support unit main body so as to be relatively movable in the axial direction,
The writing instrument according to claim 3, further comprising biasing means for biasing the chuck unit or the chuck support unit main body forward with respect to the rotating body or the barrel. The chuck unit is biased rearward by a first biasing force with respect to the chuck support unit,
The writing instrument according to claim 1, wherein the chuck support unit is biased rearward with respect to the barrel with a second biasing force larger than the first biasing force.   The writing instrument according to claim 5, wherein when the writing core is pressed rearward with respect to the barrel, the chuck unit moves relative to the barrel back. The chuck support unit has a chuck support unit main body for supporting the chuck unit, and a support which is supported by the chuck support unit main body and is movable relative to the chuck support unit main body in the axial direction.
The chuck unit is biased forward with respect to the barrel or the support,
The writing instrument according to claim 6, wherein the support is biased rearward with respect to the barrel.   The apparatus further comprises damping means for applying, to the chuck unit, a damping force according to the relative velocity of the chuck unit with respect to the barrel when the chuck unit moves relative to the barrel in the axial direction. The writing instrument as described in a 3, 4, 6 or 7.   The maximum static friction force acting between the guide pipe and the barrel is greater than the maximum static friction force acting between the guide pipe and the writing core. Writing instruments described in. With a cylinder,
A chuck support unit supported by the barrel so as to be relatively movable in the axial direction of the barrel;
A chuck unit supported by the chuck support unit so as to be movable relative to the chuck support unit in the axial direction, and holding the writing core forward.
And a guide pipe provided on the front end of the shaft cylinder so as to be movable relative to the shaft cylinder, the chuck support unit, and the chuck unit in the axial direction, and a guide pipe positioned on the writing core,
When the chuck unit is moved forward relative to the barrel,
First, the chuck unit moves forward relative to the chuck support unit,
Next, the writing instrument in which the chuck unit, the chuck support unit, and the guide pipe move forward relative to the barrel.