JP4708626B2 - Writing instrument - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a writing instrument having an ink storage tube in a shaft tube and a tail plug attached to the rear end of the shaft tube.
[0002]
[Prior art]
Conventionally, in this type of writing instrument, for example, as described in JP-A-2001-121870, a bifurcated locking piece portion is provided on the front side of the tail plug, and the tip of each locking piece portion is provided. There is one that locks the formed engaging protrusion in the shaft cylinder. The tail plug is arranged such that the length of the locking piece portion in the axial direction is not restricted by arranging the locking piece portion at a position eccentric to the shaft tube.
[0003]
However, in the writing instrument having the tail plug of the above-described conventional structure, the bifurcated locking piece portion instantaneously bends into a tapered shape due to a sudden impact such as when the writing instrument is dropped. There was a concern that the locking between the protrusion and the shaft cylinder would be released and the tail plug would come off.
[0004]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described conventional circumstances, and the object of the present invention is to reliably prevent the tail plug from being pulled out due to an unexpected impact or the like, and in the axial direction in the shaft cylinder. It is to provide a writing instrument that can make effective use of the space.
[0005]
[Means for Solving the Problems]
As a technical means of the present invention for solving the above-mentioned problems, the first invention is a writing instrument comprising an ink storage tube in a shaft cylinder and a tail plug attached to the rear end of the shaft cylinder. At least a pair of locking pieces to be inserted and locked into the shaft cylinder is provided on the mounting end side of the ink storage tube, and the rear end of the ink storage tube or the ink storage tube is interposed between the pair of locking pieces. The member connected to the rear end portion is sandwiched, and the locking state of each locking piece portion of the tail plug is maintained.
[0006]
Here, at least a pair of locking pieces means that at least two locking pieces are in one set, and are formed in multiple forks such as a bifurcated shape, a trifurcated shape, a quadrant shape, etc. Includes configuration.
Further, the member connected to the rear end portion of the ink storage tube is, for example, a pusher connected to the rear end portion of the ink storage tube of the retractable writing instrument.
The member connected to the rear end portion of the ink storage tube or the rear end portion of the ink storage tube is sandwiched between the pair of locking pieces, so that each of the engagement protrusions and the shaft cylinder are connected. As long as the locked state can be maintained, a gap may be provided between the opposing surfaces of the locking pieces.
The ink storage tube includes an ink storage tube that forms a refill of a ballpoint pen, an ink storage tube that forms the center of a batting type writing instrument, and the like.
[0007]
According to the above technical means, when the writing instrument is assembled and the tail plug is attached, the pair of locking pieces are inserted into the shaft tube and locked.
A member connected to the rear end of the ink storage tube or the rear end of the ink storage tube is sandwiched between the pair of locking pieces.
Therefore, even if the tail plug receives a sudden impact or the like, the pair of locking pieces do not bend in a tapered shape and maintains the locked state with the shaft tube.
[0008]
In the second invention, a pusher that is connected to the rear end portion of the ink storage tube and protrudes from the outer peripheral surface of the shaft cylinder is sandwiched between the pair of locking pieces.
The pusher is provided so as to slide in the axial direction between the pair of locking pieces, and a locking step formed at the front end of the locking piece when being slid forward. The protruding state of the writing tip portion is maintained by being locked to.
[0009]
Furthermore, in the third invention, the tail plug is provided with an elastic member that elastically abuts the rear end portion of the pusher.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show an example of a writing instrument according to the present invention.
In this writing instrument A, the rear end of the pusher 30 is locked by sliding the individually selected pusher 30 forward, and the protruding state of the refill 20 corresponding to the pusher 30 is maintained. This is a three-color ballpoint pen that appears and disappears. A tail plug 60 is attached to the rear end of the shaft tube 10 (see FIG. 2).
Further, a release member 50 is provided between the clip 41 and the shaft tube 10 for immersing the refill 20 in a protruding state when the object x is sandwiched (see FIG. 3).
[0011]
The shaft tube 10 is formed by screwing a rear shaft tube 12 to a front shaft tube 11 in which a grip 11b made of an elastomer resin is integrally formed by double molding (see FIG. 2).
[0012]
The rear shaft cylinder 12 has, on its peripheral wall, a fitting hole 12b for fitting the fitting protrusion 51 of the release member 50 from the inside, a window portion 12a for projecting the pushing projection 52 of the release member 50, and three Each of the two pushers 30 protrudes outside and guides and slides in the axial direction 12d, and a clip support 12e supported by a leaf spring 42 to elastically rotate the clip 41 (FIG. 3). And a tail plug insertion hole 12f (see FIG. 1) in which the tail plug 60 is mounted by the locking piece 62 is formed in the rear end opening 12g.
Further, locking step portions 12c (see FIG. 4) for locking two of the three pushers 30 are formed on the inner peripheral surface of the rear shaft cylinder 12. One of the three pushers 30 is locked to a locking step 64 at the front end of a locking piece 62 in a tail plug 60 described later (see FIG. 3).
[0013]
Each refill 20 is formed by fitting a tip 22 holding a transfer ball rotatably on the front end of an ink storage tube 21 filled with ink.
[0014]
The pusher 30 is formed with a front end fitting portion 31 to be fitted to the rear end of the ink containing tube 21 of the refill 20 at the front end portion, and at the rear end portion, the guide hole 12d of the peripheral wall of the rear shaft cylinder 12 An operation protrusion 32 is formed to protrude from the outside (see FIGS. 2 to 4).
Further, the pusher 30 has a first protrusion 33 at a midway portion in the longitudinal direction of the half half opposite to the operation protrusion 32, and a second protrusion 34 at the rear end side of the first protrusion 33. Projecting in the centripetal direction.
[0015]
Each pusher 30 has a front end fitting portion 31 fitted to the rear end of the refill 20 and is urged rearward by a spring 71 so that each operation protrusion 32 is moved to the rear end of the rear shaft cylinder 12. It is accommodated in the shaft cylinder 10 together with the refill 20 in a state of protruding from each guide hole 12d.
[0016]
Therefore, in order to immerse the refill 20 in the protruding state by the protruding operation of the other refill 20, as shown in FIG. 4, when the pusher 30 of the left refill 20 in the immersive state is slid forward, the pusher 30 The first protrusion 33 of the child 30 pushes up the second protrusion 34 of the pusher 30 of the right refill 20 in the protruding state, the right pusher 30 is unlocked, and the protruding right refill 20 is immersed. (See FIG. 4C).
[0017]
The tail plug 60 includes a tail crown portion 61 that closes the rear end opening 12g of the rear shaft tube 12, and a pair of locking pieces 62 and 62 inserted into the shaft tube.
[0018]
The pair of locking pieces 62, 62 are formed in a bifurcated shape, and when mounted on the rear shaft cylinder 12, their front end sides are bent to approach each other, and the bending is returned to return the rear shaft. The outward engaging projection 63 is locked in the cylinder 12. The engaging protrusion 63 has a locking step 64 (on the back side in FIG. 2) for locking the pusher 30 at its front end.
[0019]
More specifically, when the tail plug 60 is attached to the tail plug insertion hole 12f of the rear shaft cylinder 12, as shown in FIG. It is inserted into the tail plug insertion hole 12f while bending the sides close to each other (see FIG. 1 (a)).
In the tail plug 60, the pair of locking pieces 62 and 62 lock the engaging protrusions 63 and 63 to the step 12 h at the front end of the tail plug insertion hole 12 f in the rear shaft cylinder 12. Thus, it is mounted on the rear shaft cylinder 12 so as not to come out rearward (see FIG. 1B).
[0020]
And a pair of latching piece parts 62 and 62 maintain the latching state with 12 f of tail-plug insertion holes by inserting the rear part side of the presser 30 between them (refer FIG.1 (c)). .
[0021]
Further, an elastic member 90 is fitted on the front end side of the tail cap portion 61 of the tail plug 60.
The elastic member 90 is made of an elastic material such as an elastomer resin, and when the refills 20 are immersed from the protruding state, the respective refills 20 are elastically brought into contact with each other, so The rearward impact (back shock) received is reduced, and writing fraud and writing are prevented from being caused by the intrusion of air from the tip of the writing into the chip 22.
[0022]
The release member 50 is formed in a substantially rod shape with a resin material having toughness such as polyacetal, and has a fitting protrusion 51 that protrudes in the centrifugal direction of the shaft tube 10 on one end side (lower side in FIG. 2). On the other end side, there are a pushing protrusion 52 that protrudes in the centrifugal direction of the shaft tube 10 and a release protrusion 53 (see FIG. 3) that protrudes in the centripetal direction of the shaft tube 10. The release member 50 is configured so that the fitting protrusion 51 is fitted to the rear shaft cylinder 12 in a state where the pushing protrusion 52 is protruded from the window portion 12 a of the rear shaft cylinder 12 to the back surface side of the clip 41. The hole 12b is fitted and fixed.
[0023]
The release member 50 is bent in the centripetal direction of the shaft tube 10 when the pushing protrusion 52 is pushed and moved by the object x to be held between the clip 41 and the rear shaft tube 12. Then, the release protrusion 53 that is pushed together with the pushing projection 52 by the bending pushes the latched pusher 30 in the centrifugal direction to disengage from the latching step 12c or 64 (see FIG. 3). ).
[0024]
The pushing protrusion 52 of the release member 50 has a flat portion 52a at the top thereof, while the inner surface of the clip 41 has a plurality of ribs 41a that abut against the flat portion 52a. And by having these flat part 52a and the rib 41a, it is preventing that the to-be-clamped object x will bend and will interfere with cancellation | release operation | movement.
That is, for example, when the top of the pushing protrusion 52 is formed in a triangular protrusion and the clip 41 does not have the rib 41a, the sandwiched object x has a top shape of the pushing protrusion 52. Accordingly, the release member 50 will not be pushed.
[0025]
Reference numeral 80 in the drawing denotes a guide body that is fitted to the front end side in the rear shaft cylinder 12 and through which the refill 20 is inserted. The guide body 80 guides the three refills 20 so that each of the three refills 20 is slid in the axial direction, and receives the tip of each spring 71 that urges each of the three pushers 30 backward, By pressing the back surface side of the fitting projection 51 of the release member 50, the fitting between the fitting projection 51 and the fitting hole 12b of the rear shaft cylinder 12 is reinforced.
[0026]
Thus, according to the writing instrument A having the above-described configuration, the tail plug 60 is connected to the rear end portion of the ink containing tube 21 of the refill 20 between the bifurcated engagement protrusions 63 and 63. Therefore, even if an unexpected impact or the like is received, the engagement state between the engagement protrusion 63 of each engagement piece 62 and the step portion 12h in the rear shaft cylinder 12 is maintained.
[0027]
In the above-described embodiment, a three-color ballpoint pen is configured. However, a single-color ballpoint pen or a multicolored ballpoint pen of two colors or four colors or more can be freely configured.
[0028]
In the above-described embodiment, the retractable ballpoint pen is configured. However, it is also possible to configure a single color ballpoint pen in which the refill is fixed and the writing tip portion is not retracted. In the case of this configuration, since the pusher is not necessary, the rear end portion of the refill may be directly sandwiched between the pair of locking pieces.
[0029]
In the above-described embodiment, one of the three pushers 30 is sandwiched between the bifurcated locking pieces 62, 62, but three sets of the bifurcated locking pieces 62, 62 are provided. It is also possible to provide each of the three pushers 30 in each of the three sets of locking pieces 62, 62.
[0030]
Moreover, in the said embodiment, although the latching piece parts 62 and 62 are formed in the bifurcated shape, even if it forms in the trifurcated shape, the quadrilateral shape etc. by providing three or more latching piece parts 62, it is. I do not care.
[0031]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
According to the first aspect of the present invention, since the member connected to the rear end portion of the ink storage tube or the rear end portion of the ink storage tube is sandwiched between the pair of locking pieces, It is possible to reliably prevent the tail plug from coming out of the shaft tube without releasing the engagement between the front end side of the stopper piece and the shaft tube.
In addition, since the member connected to the rear end portion of the ink storage tube or the rear end portion of the ink storage tube is sandwiched between the pair of locking pieces, the axial space in the shaft cylinder can be effectively used. For example, it is possible to store a long ink containing tube with a large amount of ink in the shaft tube, or conversely, to shorten the overall length of the shaft tube.
Furthermore, according to the second invention, since the pusher that slides in the axial direction can be locked to the locking step formed on the locking piece portion of the tail plug, the inner peripheral surface of the shaft tube has a simple shape. As a result, the moldability of the shaft tube can be improved.
Furthermore, according to the third aspect of the invention, since the impact (back shock) when the writing tip portion is immersed is absorbed by the elastic member, it is possible to prevent writing wrinkles or writing errors due to the back shock.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part sequentially showing (a) to (c) a state in which a tail plug is assembled to a shaft cylinder and prevented from being pulled out by a pusher in an example of a writing instrument according to the present invention.
FIG. 2 shows an exploded front view of the writing instrument.
FIGS. 3A and 3B are longitudinal sectional views sequentially showing a state in which the refill is immersed by the object to be clamped being sandwiched between the clip and the shaft tube, and FIG. The refill is omitted.
FIG. 4 is a longitudinal sectional view of the writing instrument, where (a) shows a state where each refill is immersed, (b) shows a state where individually selected refills are projected, and (c) shows other By projecting the refill, the state where the selected refill is immersed is shown.
[Explanation of symbols]
10: Shaft cylinder 21: Ink storage tube 30: Pusher 60: Tail plug 62: Locking piece 63: Engaging protrusion 64: Locking step 90: Elastic member A: Writing instrument

Claims (3)

In a writing instrument having an ink storage tube in the shaft tube and a tail plug attached to the rear end of the shaft tube,
At least a pair of locking pieces inserted into the shaft cylinder and locked on the mounting end side of the tail plug is provided, and the rear end of the ink containing tube or the ink is interposed between the pair of locking pieces. A writing instrument characterized in that a member connected to the rear end of the receiving tube is sandwiched to maintain the locking state of each locking piece of the tail plug. A pusher that is connected to the rear end portion of the ink storage tube and protrudes from the outer peripheral surface of the shaft cylinder is sandwiched between the pair of locking pieces.
The pusher is provided so as to slide in the axial direction between the pair of locking pieces, and a locking step formed at the front end of the locking piece when being slid forward. The writing instrument according to claim 1, wherein the protruding state of the writing tip portion is maintained by being locked to. The writing instrument according to claim 2, wherein the tail plug is provided with an elastic member that elastically abuts the rear end portion of the pusher.

Images