JP2010173173A - Writing utensil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a writing utensil which can easily increase the stroke amount of a writing lead while saving space in a cam mechanism. <P>SOLUTION: The cam mechanism 33 of the writing utensil 30 comprises: first and second cams 34 and 35 which extend in an almost truncated chevron shape, sloping over the outer circumferential surface of a second rotating part 31; a first guide protrusion 36 which is formed jutting out to the inner surface of a barrel body 2A and engages with the first cam 34; and a second guide protrusion 37 which is installed at the apex of a holder 38 to which a writing lead 6 is fixed and engages with the second cam 35. The second rotating part 31 is freely movably connected with a barrel 2 in the extension direction of the center axis line L, through the first cam 34 and the first guide protrusion 36. The holder 38 is movably connected with the second rotating part 31 in the extension direction of the center axis line L, through the second cam 35 and the second guide protrusion 37. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is applied to a ballpoint pen, a sign pen, and the like, and relates to a writing instrument configured to project the tip of a writing core from a shaft tube by operating an operation unit provided outside the shaft tube.

  Conventionally, there is JP-A-2001-29395 as a technology in such a field. In the writing instrument described in this publication, when the knock button (operation unit) is pressed, the tip of the knock button rotates along the inclined portion of the slider provided at the tip of the refill cover body. Thereby, the refill cover body moves forward, and the tip of the refill fixed to the refill cover body can be protruded from the shaft portion.

JP 2004-98369 A JP 2001-293955 A

  However, in the above-mentioned conventional writing instrument, the wedge button linear conversion operation of the knock button is immediately converted into the linear operation of the writing core, so that the writing core with the predetermined pressing operation amount of the knock button is used. If the stroke amount of the cam mechanism is to be increased, the cam mechanism becomes large and it is difficult to save the space of the cam mechanism.

  It is an object of the present invention to provide a writing instrument that can easily increase the stroke amount of the writing core while saving the space of the cam mechanism.

The present invention, in a writing instrument configured to project the tip of the writing core from the shaft cylinder by operating the operating portion provided on the outside of the shaft cylinder,
A rotating unit that is arranged in the shaft cylinder and that rotates by receiving the pressing force of the operating unit, and that is provided in the rotating unit, converts the rotation of the rotating unit into a straight line, and the writing core is the central axis A cam mechanism that moves in the extending direction of
The cam mechanism
First and second cam portions located on the circumferential surface of the rotating portion;
A first guide protrusion formed on the inner surface of the shaft tube and engaged with the first cam portion;
A second guide protrusion provided on a holder to which a writing core is fixed and engaged with a second cam portion;
The rotating part is connected to the shaft cylinder so as to be movable in the extending direction of the central axis via the first cam part and the first guide protrusion,
The holder is characterized in that the holder is movably connected to the rotating portion in the extending direction of the central axis via the second cam portion and the second guide protrusion.

  In the cam mechanism employed in this writing instrument, since the first guide projection is fixed to the shaft cylinder, when the rotating part rotates, the rotating part is moved to the center axis line by the first cam part. The holder moves in the extending direction, and further, the holder moves in the extending direction of the central axis by the rotation of the rotating portion. In other words, the holder to which the writing core is fixed adds the movement amount of the rotating part in addition to the movement amount of itself, so that a large stroke amount is obtained when the writing core appears and disappears. This is effective as a technique for greatly moving the writing core with a small operation amount of the operation unit. In addition, the cam mechanism having the above-described configuration can increase the stroke amount of the writing core while saving space.

Further, it is preferable that the operation portion is provided with an operating piece that engages with the power point portion.
In such a configuration, the operating piece rotates the first rotating portion by a predetermined angle. In this case, when the operating piece presses the power point provided in the first rotating portion, the first rotating portion can be reliably rotated by a predetermined angle by the operating piece.

In addition, the torsion extends along the extending direction of the central axis, and one end is connected to the rotating portion, the other end is fixed in the circumferential direction with respect to the shaft tube, and is freely movable in the extending direction of the central axis. It is preferable to further include a spring.
By adopting the torsion spring having such a configuration, the writing instrument can be reduced in weight, the number of parts can be reduced, and the spring function can be easily incorporated as compared with the case where a torsion coil spring or the like is used.

The cam portion is preferably provided with a locking portion for locking the guide protrusion.
If such a configuration is adopted, the guide projection is locked to the locking part after operation of the operating part, so that even if the finger is pulled from the operating part, the operating part does not return immediately, and the operation is performed with a slight time lag. Part returning operation can be performed. Thereby, the further improvement of the operation feeling of an operation part can be aimed at.

  According to the present invention, the stroke amount of the writing core can be easily increased while saving the space of the cam mechanism.

It is an external appearance perspective view which shows one Embodiment of the writing instrument which concerns on this invention. It is a longitudinal cross-sectional view of FIG. It is a perspective view which shows the internal structure of the writing instrument shown by FIG. It is sectional drawing which shows the rotation state of the 1st rotation part by an operation part. It is sectional drawing which shows the state in which the writing core was buried in the axial cylinder. It is sectional drawing which shows the state which the writing core protruded from the axial cylinder.

  Hereinafter, preferred embodiments of a writing instrument according to the present invention will be described in detail with reference to the drawings. In the following description, the pen tip side is referred to as “front side”.

  As shown in FIGS. 1 to 3, the writing instrument 30 is accommodated in the cylindrical tube 2, the operation unit 3 provided on the peripheral surface side of the shaft tube 2 for pressing with a finger, and the shaft tube 2. The first rotation part 4 which is located on the front side of the shaft cylinder 2 and rotates about the central axis L by the pressing of the operation part 3 and the first rotation part 4 housed in the shaft cylinder 2 and the first rotation A second rotating portion 31 that is located behind the portion 4 and has a larger radius of rotation than the first rotating portion 4 and rotates together with the first rotating portion 4; It is located on the outer peripheral side of the rotation unit 31 and converts the rotation of the second rotation unit 31 into a straight line to move the writing core (for example, a ballpoint pen core or a sign pen core) 6 in the extending direction of the central axis L. And a cam mechanism 33 to be operated.

  The shaft tube 2 includes a cylindrical shaft body 2A and a conical base 2B screwed to the tip of the shaft body 2A. The rear end of the shaft cylinder 2 is covered with an end cap 8.

  As shown in FIGS. 3 and 4, the operation portion 3 extends in the extending direction of the central axis L as a part of the shaft cylinder main body 2A by a U-shaped notch 2a formed in the shaft cylinder main body 2A. A long lever portion (operation main body portion) 3a that exists and protrudes toward the first rotating portion 4 at the distal end side of the lever portion 3a, and the outer peripheral surface of the first rotating portion 4 is substantially tangent. An operating piece 3b is provided that presses in the direction and rotates the first rotating portion 4 in the direction of arrow A. And the connection part of the lever part 3a and the action piece 3b is formed as the thin neck part 3c which enables the action piece 3b to rock | fluctuate.

  Three lever portions 3a are provided every 120 degrees in the circumferential direction of the shaft cylinder main body 2A, and three operation pieces 3b are also provided correspondingly. In addition, a finger rest 3d that protrudes from the outer peripheral surface of the shaft cylinder main body 2A is integrally formed on the distal end side of the lever portion 3a so that the three fingers reliably come into contact with the writing instrument 30. By configuring in this way, the finger contact part 3d of each lever part 3a can be pushed with three fingers, so compared with the case where the first rotating part 4 is rotated with one lever part. The force applied to each lever portion 3a can be reduced, and the operability of the lever portion 3a is thereby improved.

  Since the tip of the operating piece 3b is fitted in a concave force point 4a provided on the outer peripheral surface of the first rotating part 4, the pressing force of the operating piece 3b is firmly applied to the first rotating part 4. I can tell you. Furthermore, the outer peripheral surface of the 1st rotation part 4 is formed in the substantially radial direction, and the latching piece 4b which latches the action | operation piece 3b is formed, and each latching piece 4b is each of the concave force point part 4a. Is extended in the extending direction of the central axis L.

  When the operating piece 3b rotates the first rotating portion 4 by a predetermined angle, the tip of the operating piece 3b comes into contact with the concave force point portion 4a provided in the first rotating portion 4 so that the operating piece The first rotation part 4 can be reliably rotated by a predetermined angle by 3b. Further, since the free end of the locking piece 4b slides along the inner peripheral surface of the shaft cylinder main body 2A when the first rotating part 4 is rotated, the first rotating part 4 is rotated. It also has the role of stabilizing.

  Further, a ring-shaped protrusion 4c for reducing rotational friction with respect to the front end wall 2d (see FIG. 2) of the shaft cylinder main body 2A is provided at the tip of the first rotating portion 4. As a result, the first rotation portion 4 can be smoothly rotated without the locking piece 4b hitting the front end wall 2d of the shaft cylinder main body 2A.

  As shown in FIG. 2 and FIG. 3, the second rotating part 31 having a larger turning radius than the first rotating part 4 is formed in a cylindrical shape so that the writing core 6 can pass through the central axis L. It is connected to the 1st rotation part 4 by the connection pipe 22 which can be expanded-contracted in the extending direction. A through hole 4d through which the writing core 6 can pass is formed in the center of the first rotating portion 4, and the writing tool 30 is formed by matching the hole center of the through hole 4d with the hole center of the connecting pipe 22. The writing core 6 can be arranged along the central axis L.

  The connecting pipe 22 has a front end fixed to the first rotating portion 4 and a first pipe portion 22A in which a slide rail 22a extending in the extending direction of the central axis L is formed on the outer peripheral surface, and the rear The end is fixed to the second rotating portion 31 and includes a second pipe portion 22B in which a slide groove 22b into which the slide rail 22a is fitted is formed on the inner peripheral surface. With such a configuration, the first rotating unit 4 and the second rotating unit 31 can be rotated together, and at the same time, the second rotating unit 31 is moved with respect to the first rotating unit 4. It can be moved in the extending direction of the central axis L.

  A torsion spring 10 having two elastic pieces 10 a extending in the extending direction of the central axis L in a pair so as to sandwich the central axis L is fixed to the rear end of the second rotating portion 31. Yes. Each elastic piece 10a is formed of a resin having a twist restoring force. The front end of each elastic piece 10a is integrated with the second rotating portion 31, and the rear end of each elastic piece 10a is integrated with the ring portion 10b. And the protrusion 10c formed in the ring part 10b fits into the slit 2b extending in the extending direction of the central axis L along the inner peripheral surface of the shaft tube main body 2A, so that the rear end of the torsion spring 10 Is fixed in the circumferential direction with respect to the shaft cylinder main body 2A, thereby enabling the second rotating portion 31 to be rotated and returned.

  By adopting the torsion spring 10 having such a configuration, the writing instrument 30 can be reduced in weight, the number of parts can be reduced, and the spring function can be easily incorporated as compared with the case where a torsion coil spring or the like is used.

  Next, a set of two cam mechanisms 33 arranged every 180 degrees in the circumferential direction will be described.

  Each cam mechanism 33 is located on the peripheral side of the second rotating portion 31, converts the rotation of the second rotating portion 31 into a straight line, and extends the writing core 6 in the extending direction of the central axis L. Move to. Further, each cam mechanism 33 includes first and second cam portions 34 and 35 that are inclined on the peripheral surface of the second rotating portion 31 and extend in a substantially C shape, and the inner surface of the shaft cylinder main body 2A. The first guide protrusion 36 that is formed so as to protrude to the first cam portion 34 and the tip of the holder 38 to which the writing core 6 is fixed is connected to the second cam portion 35. And a second guide projection 37 to be joined.

  The second rotating portion 31 is connected to the shaft cylinder 2 through the first cam portion 34 and the first guide projection 36 so as to be movable in the extending direction of the central axis L, and the holder 38 is The second rotating portion 31 is connected to the second rotating portion 31 so as to be movable in the extending direction of the central axis L via the second cam portion 35 and the second guide protrusion 37.

  The first cam portion 34 and the second cam portion 35 arranged side by side in the extending direction of the central axis L are part of the contour of the opening 39 formed on the outer peripheral surface of the second rotating portion 31. It is formed, extends so as to be inclined with respect to the central axis L, and has a symmetric relationship with respect to a plane orthogonal to the central axis L. When the angle formed between the central axis L and the first cam portion 34 and the angle formed between the central axis L and the second cam portion 35 are defined as the cam angle α, the writing core 6 increases as the cam angle α increases. Is moved by a predetermined amount, the rotation angle of the second rotation unit 31 is increased. The cam angle α on the first cam portion 34 side and the cam angle α on the second cam portion 35 may be the same or different.

  Further, on the terminal side of the first and second cam portions 34, 35, a member extending in the circumferential direction of the second rotating portion 31 to lock the first and second guide protrusions 36, 37. Stop portions 34a and 35a are provided.

  When the first and second guide protrusions 36 and 37 are locked to the locking portions 34a and 35a, the lever portion 3a returns immediately even if the finger force is removed from the finger contact portion 3d of the lever portion 3a. However, the return operation of the lever portion 3a can be performed with a slight time lag. Thereby, the further improvement of the operation feeling of the finger | toe contact part 3d of the lever part 3a can be aimed at. Note that the interval of the time lag can be arbitrarily set by appropriately adjusting the shapes such as the angles of the locking portions 34a and 35a.

  An inner cylinder part 40 located inside the second rotation part 31 is provided on the tip side of the holder 38, and moves along the second cam part 35 on the outer peripheral surface of the inner cylinder part 40. A second guide protrusion 37 is formed. The holder 38 is provided with a pipe-like holder main body 41 for press-fitting and fixing the writing core 6, and the tip of the holder main body 41 is integrated with the end surface of the inner cylinder portion 40.

  Further, the inner cylinder portion 40 is formed with a protrusion 40a that fits into a slit 2b formed on the inner peripheral surface of the shaft cylinder main body 2A. By the cooperation of the slit 2b and the protrusion 40a, the holder 38 and the writing core 6 can be reliably moved in the extending direction of the central axis L. In order to prevent the holder 38 from rattling, the rear portion of the holder 38 is inserted into the insertion hole 8 a of the end cap 8.

  Further, a first coil spring 43 is disposed between the second rotating part 31 and the inner cylinder part 40, and a first coil spring 43 is disposed between the first rotating part 4 and the second rotating part 31. Two coil springs 44 are arranged. The first rotating part 4 is lightly pressed by the second coil spring 44 against the front end wall 2d of the shaft cylinder main body 2A, and the first rotating part 4 can be prevented from rattling. The first coil spring 43 can reliably retract the holder 38 and the writing core 6 in a steady state.

  The operation of the writing instrument 30 will be briefly described.

  When the writing instrument 30 is grasped with a finger and the finger contact part 3d of each lever part 3a is pushed in with the finger, the first turning part 4 is turned by a predetermined turning angle by the operating piece 3b (see FIG. 4). Simultaneously with this rotation, the second rotating portion 31 also rotates. As shown in FIG. 6, the first and second guide protrusions 36, 37 are formed along the first and second cam portions 34, 35. The second rotating portion 31 and the holder 38 move toward the front side in the extending direction of the central axis L while sliding so as to approach each other and the connecting pipe 22 contracts. Accordingly, the writing core 6 moves forward in the extending direction of the central axis L. Finally, the first and second guide protrusions 36 and 37 hit the locking portions 34a and 35a, and the writing core 6 protrudes from the shaft cylinder 2 to the maximum extent. At this time, the protrusion 10c of the torsion coil spring 10 moves in the extending direction of the central axis L along the slit 2b, and each elastic piece 10a of the torsion spring 10 is in a state of being twisted to the maximum.

  Thereafter, the first and second rotating parts 4, 31 are moved by the elastic force of the elastic pieces 10 a of the first coil spring 43 and the torsion spring 10 by loosening the force that pushes the finger contact part 3 d of each lever part 3 a. Reverse rotation is started, and the guide protrusions 36 and 37 slide along the cam portions 34 and 35. Then, following the movement of the guide protrusions 36 and 37, the second rotating portion 31 and the holder 38 are retracted in the extending direction of the central axis L, and the tip of the writing core 6 is stored in the shaft tube 2. As described above, the writing tool 30 can cause the writing core 6 to appear and disappear without changing, and there is no trouble of changing the writing like a writing tool having a knock mechanism.

  In such a writing instrument 30, the first rotation unit 4 that rotates with a small rotation radius is rotated about the central axis L by the operation unit 3, and the first rotation unit 4 rotates together with the first rotation unit 4. The second rotating portion 31 rotates with a radius, and the cam mechanism 33 is disposed on the circumferential side of the second rotating portion 31. Accordingly, the amount of rotation of the first rotation unit 4 by the operation unit 3 is amplified by the second rotation unit 31, and even if the first rotation unit 4 has a small rotation amount, the second rotation unit 31. A large amount of rotation can be obtained. Then, by utilizing the amplified rotation amount, the cam mechanism 33 converts the rotation motion of the second rotation portion 31 into a linear motion, and the writing core 6 projects greatly along the central axis L by this linear motion. Can be made.

  Further, in the writing instrument 30, the cam mechanism 33 that converts the rotation of the second rotating portion 31 into the linear movement of the writing core 6 is employed, so that the cam mechanism 33 is provided in the vicinity of the inner peripheral surface side of the shaft tube 2. As a result, the cam mechanism 33 can be easily saved in space and reduced in size in the shaft cylinder 2, and the light weight can be easily reduced.

  As shown in FIG. 4C, even if the amount of pushing operation of the operation unit 3 is small and the amount of rotation of the first rotation unit 4 (see arrow B) is small, the second rotation unit 31 is amplified. The writing core 6 can be moved greatly by the action (see arrow C). Therefore, since the amount of pressing operation of the operation unit 3 is small, an excellent effect of improving the operational feeling of the operation unit 3 during writing can be obtained.

  In the cam mechanism 33, two pairs of cam portions 34 and 35 and guide protrusions 36 and 37 are employed, and the writing core 6 is moved away from the shaft tube 2 by a very small pushing operation amount of the finger contact portion 3d of the lever portion 3a. It can be infested.

  In this case, since the first guide protrusion 36 is fixed to the shaft cylinder 2, when the second rotating portion 31 is rotated, the second rotating portion 31 is moved to the central axis L by the first cam portion 34. Further, the holder 38 moves in the extending direction of the central axis L by the rotation of the second rotating portion 31. Therefore, the holder 38 to which the writing core 6 is fixed adds the movement amount of the second rotating portion 31 in addition to the movement amount of the holder 38 itself. This is effective as a technique for greatly moving the writing core with a small operation amount. Moreover, the cam mechanism 33 configured as described above can increase the stroke amount of the writing core 6 while saving space.

  It goes without saying that the present invention is not limited to the embodiment described above.

  For example, as another writing tool (not shown), the first rotating unit 4 or the second rotating unit 31 is moved by pushing a knock unit (operation unit) provided at the rear end of the outer side of the barrel 2 with a finger. The structure to rotate may be sufficient.

  DESCRIPTION OF SYMBOLS 30 ... Writing instrument, 2 ... Shaft cylinder, 3 ... Operation part, 3a ... Operation main-body part (lever part), 3b ... Operation piece, 4 ... 1st rotation part, 4a ... Power point part, 4b ... Locking piece, 31 ... 2nd rotation part, 6 ... writing core, 33 ... cam mechanism, 10 ... torsion spring, 34, 35 ... cam part, 34a, 35a ... locking part, 38 ... holder, 36, 37 ... guide protrusion, L ... center axis.

Claims (4)

In the writing instrument configured to project the tip of the writing core from the shaft cylinder by operating the operation unit provided on the outside of the shaft cylinder,
A rotating portion that is disposed within the shaft tube and rotates in response to a pressing force of the operation portion;
A cam mechanism that is provided in the rotating part, converts the rotation of the rotating part into a straight line, and moves the writing core in the extending direction of the central axis,
The cam mechanism is
First and second cam portions located on the circumferential surface of the rotating portion;
A first guide protrusion formed on an inner surface of the shaft tube and engaged with the first cam portion;
A second guide projection provided on a holder to which the writing core is fixed and engaged with the second cam portion;
The rotating portion is connected to the shaft cylinder so as to be movable in the extending direction of the central axis via the first cam portion and the first guide protrusion,
The writing instrument is characterized in that the holder is connected to the rotating part via the second cam part and the second guide protrusion so as to be movable in the direction in which the central axis extends.   The writing instrument according to claim 1, wherein an operating piece that engages with the power point portion is provided in the operation portion.   Extending along the extending direction of the central axis, one end is connected to the rotating portion, the other end is fixed in the circumferential direction with respect to the shaft tube, and is movable in the extending direction of the central axis 3. The writing instrument according to 1 or 2, further comprising a torsion spring.   The writing instrument according to any one of claims 1 to 3, wherein the cam portion is provided with a locking portion for locking the guide protrusion.

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