JP3361900B2 - Knock-type writing instrument - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a so-called knock type ball-point pen in which a writing body such as a ball-point pen can be projected and retracted from a tip end of a barrel.

[0002]

2. Description of the Related Art FIG. 1 shows a conventional writing instrument which is composed of a shaft cylinder, a knock rod, a writing body, and a return spring. is there. However, when replacing the writing body of this writing instrument, as shown in FIG.
For example, by pressing the locking portion of the knock bar with the tip of a ballpoint pen to release it from the locking surface of the barrel and remove the knock rod to replace the cursive body, or as shown in FIG. The writing body and the return spring are housed in the rear axle as two parts, and the rear axle is detachably screwed to the front axle, and the writing body is replaced by attaching and detaching the front axle. Therefore, since the one locking portion of the knock bar locks at the forward movement position and the backward movement position, a heavy load is applied to the locking portion at the time of impactingly abutting and locking the backward movement position, which is called durability. I am worried about the point.

[0003]

By the way, in the conventional writing instrument shown in FIGS. 1 and 2, it is difficult to replace the writing instrument because an auxiliary tool is required for exchanging the writing instrument. Figure 3
In the writing instrument of the conventional example shown in (1), there is a problem that the cost of materials and assembling costs increase due to the increase in the number of parts. or,
In the above-mentioned structure, a load is constantly applied to the locking portion of the knock bar regardless of the appearance of the writing body, the locking portion and the arm are easily bent, and the knock mechanism may not operate normally. Book
An object of the invention is to solve such a problem.

[0004]

In order to solve the above-mentioned problems, in the knock-type writing instrument of the present invention, two locking portions are provided on the knock rod, and one writing portion projects the writing body from the tip of the shaft. It has a cam function that allows it to slide in either position or a position retracted into the shaft, and a fixed locking action when the writing body projects from the tip of the shaft. It is possible to prevent disengagement from the shaft cylinder when it is stored in, and to disengage the knock bar when the locking portion is released from the shaft cylinder locking surface, so that the writing body can be replaced. Further, in the locking for a retracted position in the projecting position cursive the locking portion of the knock bar
It is characterized in that by providing two for locking, the load is not applied to the locking portion having the cam action when the writing body is in the retracted position.

[0005]

FIG. 4 to FIG. 8 show an embodiment of the present invention. First, as shown in FIGS. 4 and 5, the writing body 3 is housed in the barrel 1 in a state of being biased rearward by the return spring 4 and is locked at two positions interlocking with the writing body 3 in the axial direction. The knock bar 2 having the above is arranged at the rear end of the writing body 3.
The cursive body 3 has a check ball 6 housed therein and a ball-point pen tip 8 and an ink storage tube 9 are press-fitted into a joint 7 having a function of preventing backflow of ink. The ink containing tube 9 has low viscosity or basically has low viscosity, but statically has high viscosity, and the viscosity can be lowered by the rotation of the tip ball at the time of writing to allow the ink to flow out. The ink having the shear thinning property is filled, and the trailing end of the ink is also filled with a grease-like follower that can move in contact with and follow the ink surface as the ink is consumed. Further, a resin-made follower rod 10 is enclosed in the follower so that the center portion of the follower having fluidity is not deformed due to the impact or the like. A transparent PP resin molded product or the like is used for the ink containing tube.

The knock rod 2 also has a cam mechanism for knocking operation, a first actuating locking portion 11 for locking at the projecting position, and a mechanism for exchanging cursive materials, so that the knocking rod 2 can be operated at the retracted position. The second fixed locking portion 12 for locking is provided with two locking portions. The operation locking portion 11 is located at the tip of the arm 13 which is perpendicular to the axis and has elasticity in the guide window direction. Further, as shown in the figure, the elastic portion 14a provided by forming a thin cut-out portion near the front end of the base portion 14 can be appropriately swung in the direction perpendicular to the axis line, so that the displacement of the arm 13 is smoothed. can do. Here, in order to increase the restoring force of the arm 13, the contact portion 15 of the arm 13 with the writing body 3 is slightly angled with respect to the writing body 3. Contact part 1 of arm 13 with cursive body 3
When the writing body 5 is pressed by the cursive body 3, a moment is generated and the actuating locking portion 11 on the arm 13 exerts a force to return to the original position. The strength of the moment can be adjusted by appropriately determining the size and position setting of the elastic portion 14a.
The protrusion 16 is for increasing the elastic force of the arm 13 in the guide window direction, and by applying the elastic force to the arm 13, it is possible to prevent an uncertain operation of the operation locking portion 11. In FIG. 4, the protrusion 16 is provided on the opposite side of the arm 13, but the protrusion 16 can be provided on the arm 13 itself. Further, adjusting the elastic force of the arm 13 by making the protrusion itself elastic is also an effective means for reliable operation. The fixed locking portion 12 is connected to the free end of the elastic piece 17 and can swing in the direction perpendicular to the axis. The flat surface 32 is provided so as not to interfere with the inclined surface 20 provided inside the barrel 1. The guide 33 is for the knock rod to slide inside the barrel parallel to the axis. It is desirable in terms of cost to integrally form each part of the knock rod 2 with a resin molded product having excellent elasticity.

7 and 8 show each part of the guide window with respect to the actuating locking part 11. An upper guide window and a lower guide window are provided in the barrel 1. Further, a groove 18 and a groove 19 for moving the operation locking portion 11 from one guide window to the other guide window.
Is provided on the inner surface of the barrel 1. Groove 1 on the inner surface of barrel 1
An inclined surface 20 is formed between the groove 8 and the groove 19.

[0008]

The operation will be described below based on the above embodiment.
The arrow in FIG. 7 indicates the movement path locus of the operation locking portion 11. First, when the cursive body 3 is in the retracted position, the knock bar 2
Is locked to the rear end surface of the slit 31 by the fixed locking portion 12. When the knock rod 2 is pushed from this position, the engagement portion guide surface 21 of the actuating engagement portion 11 becomes the shaft tube guide surface 23 of the shaft tube 1.
Along to the stop wall 24. From here, the actuating locking portion 11 moves under the action of the actuating portion inclined surface 22 into the shaft cylinder and moves to the lower guide window through the groove 18 provided on the inner surface of the shaft cylinder. The arm 13 is elastic while the operation locking portion 11 moves in this way.
It remains bent in the circumferential direction by the portion 14a . When the operation locking portion 11 enters the lower guide window, the operation locking portion opens radially outward due to the elastic force of the arm. Further, the elastic locking force stored in the elastic portion 14a causes the operation locking portion 11 to contact the receiving surface. Here, when the pushing of the knock bar 2 is stopped, the operation locking portion 11 moves along the receiving surface 25 and moves toward the guide window end surface 26.
And is locked by the locking surface 27.

Further, when the writing stick 3 is in this forward position, when the knock rod 2 is pushed, the operating portion inclined surface 2 of the operating locking portion 11 is pushed.
2 moves toward the unlocking surface 28, and the operation locking portion 11 is pushed inward in the radial direction. The operation locking portion 11 has a guide window end surface 26.
The arm 13 is further disengaged, and the displacement of the arm 13 is restored to a natural state, and the arm stop surface 29 moves until it comes into contact with the side surface of the groove 19. The movement of the operation locking portion 11 to this position is facilitated by the inclined surface 20 formed between the groove 18 and the groove 19 on the inner surface of the barrel. When the operation locking portion 11 is in this position, the arm is elastically deformed radially inward. When the load on the knock bar is released, the operation locking portion passes through the groove 19 and the arm 13
The elastic force of opens to the outside in the radial direction and enters the upper guide window. At this time, the fixing locking portion 12 is the clip mounting base portion 3 of the shaft cylinder 1.
It is locked by the rear end surface of the slit 31 provided on the opposite side of 0 to prevent the knock bar 2 and the writing body 3 from falling off the shaft cylinder. The slit 31 is provided in parallel with the axis, and when the knocking operation is performed, the fixing locking portion 12 can move only in the direction parallel to the axis. Can be prevented from rotating.

When the cursive body 3 is in the retracted position, it is locked by the shaft cylinder 1 and pushes the elastic piece 17 to deform it, the fixed locking portion 12 is released from the locking surface of the slit of the shaft cylinder, and the cursive body 3 is removed. It is possible to take it out. Operation locking part 11 of knock bar
A groove 34 is provided on the inner surface of the shaft cylinder of the clip mounting portion so that the clip can be taken out without interfering with the inner surface of the shaft cylinder 1.

[0011]

The present invention is as described above, and when the cursive body is in the stored state , the elastic piece can be attached by sandwiching the knock bar.
It deforms and displaces the locking part for fixing to engage the slit of the barrel.
The cursive body can be taken out together with the knock rod by releasing the engagement with the stop surface . Further, when the cursive body is in the stored state, it is locked by the locking part for fixing, so that the operation locking part of the knock bar, which is the main part of the knocking mechanism, is not burdened at all, and the member may fall. Since there is no knock, the knocking does not make writing impossible. Further, since the writing portion can be projected and retracted only by pressing the knock, it is easy to use and the structure is simple, so that the assembly is easy and it can be provided at a low cost. Further, since the cursive body appears and disappears by repeatedly pressing the knock bar, the finger is always in contact with the knock bar. There is no need to worry about moving due to shock and disabling writing.

[Brief description of drawings]

FIG. 1 is an external perspective view of a conventional knock-type writing instrument, showing a component structure of the writing instrument.

FIG. 2 shows a method of exchanging a writing body in a state where a writing knocking tip portion of a conventional knock-type writing implement is immersed in a barrel from a tip end of a barrel.

FIG. 3 is an external perspective view of another conventional knock-type writing instrument, showing a component structure of the writing instrument.

FIG. 4 is a vertical cross-sectional view showing the entire ball-point pen that is an embodiment of the present invention, showing a state in which the writing tip is immersed.

FIG. 5 is a cross-sectional view of a main part seen through from above, which is the clip side in FIG.

FIG. 6 is an external perspective view of a knock rod used in the embodiment.

FIG. 7 is an explanatory view showing a state in which the operation locking portion of the knock rod is operated and locked with respect to the guide window portion of the shaft cylinder.

8 is a cross-sectional view taken along the line AA of the shaft cylinder portion of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Shaft cylinder 2 Knock bar 3 Writing body 4 Return spring 5 Clip 6 Non-return ball 7 Joint 8 Tip 9 Ink storage tube 10 Follower bar 11 Actuating locking part 12 Fixing locking part 13 Arm 14 Base part 14a Elastic part 15 Contact part 16 Protrusion 17 Elastic Piece 18 Groove 19 Groove 20 Sloping Surface 21 Locking Part Guide Surface 22 Actuating Part Sloping Surface 23 Shaft Cylinder Guide Surface 24 Stop Wall 25 Receiving Surface 26 Guide Window End Surface 27 Stopping Surface 28 Lock Release Surface 29 Locking Part Stop surface 30 Clip mounting base 31 Slit 32 Flat surface 33 Guide 34 Groove

Claims (4)

(57) [Claims] 1. A guide window formed in two places on a side surface of a rear end portion.
The cursive body is attached to the barrel with a return spring
Stored in the state of being biased to the
The stick is placed at the rear end of the cursive so that
Knock the rear end of the knock bar that protrudes from the rear end of the barrel.
By doing so, the operation locking part of the knock bar is attached to the edge of the upper guide window.
Move along and slide the actuating lock from the window end into the barrel.
And further advance, the operation locking part protrudes from the lower guide window.
Then, the writing tip is locked on the edge of the guide window and the writing tip is the tip of the shaft.
It protrudes from the mouth and pushes the knock bar further from that state
And the actuating locking part goes into the barrel again and slides sideways at the same time.
Then, the above-mentioned locked state is released and the cursive body retracts.
A knock-type writing instrument in which the writing tip is stored in the shaft
The knock bar, which is drilled on the side surface of the rear end of the barrel.
Lock on the edge of the lower guide window to lock the writing body in the protruding position.
Displaceable actuating lock part and the guide window on the barrel separately
Fit in the slit provided and the knock bar is
There is a displaceable locking part that can be locked in the retracted position.
They are provided integrally with each other, and the knock bar is removed from the barrel.
Projecting at the rear end of the barrel so that the cursive can be replaced.
For fixing by narrowing the rear end part of the knock bar
The locking part is displaced and the locked state is released, and
The stopper can be taken out without interfering with the inner surface of the barrel.
Grooves are provided on the inner surface of the cylinder of the clip mounting part.
A knock-type writing instrument characterized by. 2. To ensure the operation, a protrusion for increasing the elastic force toward the guide window is provided at the elastic portion of the knock rod at an angle outward to the axis, and the knock rod is pressed to activate the operation locking portion. 2. The knock according to claim 1, wherein the force applied to the actuating locking portion when moving along the guide surface of the guide window of the axial cylinder has a larger radial force than a circumferential force. Writing instrument. 3. The cursive body has a tip of a ballpoint pen at the tip and an ink containing tube at the rear, and the ink containing tube has low viscosity ink or basically low viscosity, but statically high viscosity. In addition, the ink has a so-called shear thinning viscosity in which the viscosity is reduced by the rotation of the tip ball during writing and the ink flows out, and a follower is provided at the rear end of the ink to follow the consumption of the ink. The knock-type writing instrument according to claim 1, wherein: 4. The cursive body is provided with a ball valve for preventing backflow of ink, and the follower is formed into a grease shape,
The knock-type writing instrument according to claim 3, wherein a resin-made follower rod having substantially the same specific gravity is immersed in the follower.