JP2000079790A - Writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the safety mechanism of a knocking type writing utensil so as not to spoil clothes under the state being housed in a pocket. SOLUTION: An engaging tube 9 having projections is loosely fitted to the front of a knocking rod 7 properly rotatably about the axis center line of the tube. In addition, the rear part of a refill is inserted in the engaging tube 9. An engaging part 3 is provided at the front end of a clip fixed to a shaft 1. Further, at the outer peripheral part of the shaft opposing to the engaging part, a window, through which projections 8 and 10 pierce, is bored. At the same time, by abutting the projections against the window and the cam incline formed at the front surface of the engaging part through the pressing operation of the knocking rod, the engaging tube is rotated, a writing part extends through the tip of the shaft when the projection engages with the engaging part. By the next pressing operation, the engaging tube is rotated so as to release the projection from the engaging part, resulting in allowing to retract the writing part from the tip of the shaft. Further, by displacing the front end of the clip so as to release it from the surface of the shaft, the projection is released from the engaging part, resulting in allowing to retract the writing part from the tip of the shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called knock-type writing instrument in which a refill as a writing body is protruded and written by pressing a knock bar at the rear end. The present invention relates to an improvement of a safety mechanism that does not stain clothes by releasing a lock with a locking cylinder provided so as to be interlocked and storing a refill in a shaft. In particular, the ink has high viscosity statically during non-writing, and uses a so-called shear thinning ink by rotation of the writing ball to ensure smooth writing performance, and uses the ball as a valve during non-writing. In addition, the present invention relates to an improvement in a ball-point pen aiming at improving functions such as an improvement in impact resistance performance and an ink backflow prevention performance, and an ink drop prevention in which ink moves backward to cause ink drop.

[0002]

2. Description of the Related Art A conventional knock-type ballpoint pen which does not require a cap to be attached or detached has a hole formed in a front end surface of a shaft, and a refill is protruded by pushing a knock bar to write. , When refilled in the pocket-
If the user forgets to store the cartridge, the refill remains protruding off the axis, and the pocket is stained with ink. In order to solve this problem, when writing tools are inserted into the pockets by locking the clip to the window of the clip, a structure in which the refill is always stored or a window is provided on the shaft and a locking portion is provided on the ball portion of the clip Inventors have proposed a similar operation. However, these require processing of windows and locking parts for metal clips, which are expensive and have problems in workability, sacrifice the durability of the spring of the clips, and increase the number of parts. Existed. In particular, in the safety mechanism that prevents the clothes from being soiled by the knock type, when pressing the knock bar and retracting the refill after storing it, press the rear end side of the clip and lift the clip ball part to lock it. It is generally used to release and store the refill, but in this case it is difficult to understand how to release the lock, and there is a case where it is necessary to switch because the direction of the clip with respect to the axis is There were many requests to repeat locking and releasing only with a knock bar. Furthermore, conventionally known oil-based ballpoint pens use high-viscosity ink to prevent the movement of ink, and further increase the capillary force by making the ink storage tube thinner, but this is prevented.
This causes problems such as heavy writing feeling, unevenness, unevenness of the writing line, and low density. Further, a so-called water-based ballpoint pen is known in which a low-viscosity ink is impregnated into a fibrous batting to guide the ink to the ballpoint pen tip via an ink guide core, but the consumption of the ink is not known. It is difficult to reduce the size of the shaft because it requires a padding with a certain amount of space.
Under such circumstances, a so-called neutral ballpoint pen is known which has a relatively high viscosity statically and expresses a shear thinning viscosity by writing for the purpose of solving the respective disadvantages. However, these water-based ballpoint pens and neutral ballpoint pens are often based on volatile water-based inks, and are easily dried up when mounted on a knock-type open shaft. This problem is solved by increasing the content of ink on the ink side, but these neutral ball-point pens have a problem that they tend to cause impact during storage and backflow due to upward writing. In addition, the Applicant filed 3-1
In 03787, a knock-type writing instrument that can protrude and store the refill by pressing only the knock bar was proposed.
In this case, when the refill is to be protruded from the storage state, the refill may pass through the locking portion and return to the storage state without locking the refill in some cases.

[0003]

SUMMARY OF THE INVENTION Accordingly, the present invention has as its object to improve a popular ballpoint pen, and provides a smooth operation in the case of a refill projecting operation and a storing operation, and a pocket without penalizing writing. Prevents accidents that stain clothes when stored in the storage, and solves the problem of assembly as well as cost by adopting a very inexpensive component shape and configuration, especially as a mechanism that makes it easy to project and store the refill. It is desired to do. It is another object of the present invention to provide a knock-type writing instrument which does not cause troubles such as backflow and direct current even when a so-called neutral ballpoint pen having a shear thinning property which is relatively weak to impact is used as a refill.

[0004]

In order to achieve the above object, a ballpoint pen according to the present invention comprises a refill having a writing portion at the tip, a spring 22 for urging the refill and a rear end face of the refill which is in contact with the rear end face of the refill. A knock bar 7 protruding from the shaft 1 is pressed, and the knock bar 7 is pressed to cause the refill to protrude from the front portion of the shaft 1, thereby maintaining the protruding state. It is loosely fitted between the knock bar 7 and the refill in front of the knock bar 7 so as to be able to rotate (or move laterally) with respect to the axis, and a projection 1 is provided on the outer diameter side.
0, and a clip 2 having a locking portion 3 for locking to a projection 10 of the locking cylinder 9 is fixed to the shaft 1 so as to restrict axial movement, or the shaft 1 and the clip 2 are made of resin. The shaft 1 is provided with a window at a portion corresponding to the protrusion 10 of the locking cylinder 9 and the locking portion 3 of the clip 2, and the projection 10 of the locking cylinder 9 abuts the window. In this case, the cam slopes 1a, 1b, 1c and 1d for rotating (or moving) the locking cylinder 9 are also provided on the locking portion 3 of the clip 2 and the slope corresponding to the cam slope of the shaft 1. 3-a, and the protrusion 10 of the locking cylinder 9 is rotated (or moved) by an appropriate movement amount to repeatedly lock and release with the clip 2, thereby protruding the refill and storing the refill. Is configured to be held. Here, the projection 10 of the locking cylinder 9 and the locking portion 3 of the clip 2
When it is in the locked state, the writing part of the refill protrudes from the tip of the shaft 1 and can be written. At this time, if you forget to store it and try to insert it into the pocket, the locked state is released and the refill is released. The built-in components automatically move rearward in the shaft by the urging force of the spring 22 constantly urging rearward, and the refill is stored. In this case, the unlocking method during normal use may be to press the knock rod or lift the clip ball part, especially when using a direct liquid writing instrument that is weak to impact or a refill using low viscosity ink In order to prevent the impact from being refilled, it is more safe to use a double knock type in which the protrusion and storage are repeated with only the knock bar 7. In a knock-type writing instrument utilizing such a locking mechanism with the clip 2, the clip 2 is required to have a function that does not lose its springiness even when stored in a high temperature state as compared with slightly thick clothing. The material is selected from a resin having high heat resistance and creep resistance, and an upright portion 4 for insertion into the shaft 1 and a spring portion 6 which can be elastically deformed when the clip locking portion 3 is lifted are integrally provided for permanent deformation. There is a difficult structure. The clip spring portion 6 has an upright portion 4
On the opposite side, a fixing projection 5 inserted and fixed in the fixing window 5-a of the shaft 1 and a groove 7-a that allows the knock bar 7 to pass through the spring portion 6 of the clip 2 and contact the refill.
By pressing the fixing projection 5, the clip 2, the locking cylinder 9, the knock bar 7, and the refill can be removed from the shaft 1, and the refill can be replaced. In particular, the case of a neutral ballpoint pen, which is slightly weaker in impact resistance, is described as follows. A tip 20 holding a ball serving as a writing portion at the tip, and a receiving face that holds the tip and faces the rear end surface of the tip near the axis. A valve chamber is provided with a guide hole that secures a flow path communicating the seat from the ink storage tube to the ball of the writing section, and a ball valve 18 is loosely fitted in the valve chamber, and the pen body faces upward. When the ball valve 18 is in close contact with the receiving seat and the guide hole is closed, backflow of ink is prevented, and when writing with the pen body facing downward, the ball valve 18 abuts on the rear end of the chip 20 and ink flows in. A backflow prevention mechanism that secures a path for writing and enables writing is provided. Further, the ink 16 having a so-called shear thinning viscosity, which has a high viscosity and has a reduced viscosity due to the shearing force caused by the rotation of the ball as the writing portion, so that the ink easily flows even in light writing, and with the consumption of the ink, As a ballpoint pen having a transparent or translucent resin ink container 12 for accommodating a grease-like follower 15 to be followed, a tail plug 1 is provided at the rear end side of the ink container.
3 and a ball-point pen having an air flow passage between the tail plug 13 or the tail plug 13 and the ink containing tube 12. In order to further enhance the backflow prevention effect, the tip 20 for loosely fitting the ball as the writing portion and the ball for the writing portion are pressed very weakly by the tip spring 19 to caulk the ball for the writing portion and the tip 20 which has been prevented from coming off. Since these parts form a valve structure, they have the same effect as the above-described backflow prevention mechanism.
At the time of writing, the ink passage required for writing is secured and writing is performed like a general ballpoint pen.

[0005]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to 6 show a first embodiment of the present invention. As shown in the figure, a transparent or translucent resin
A ball receiving seat having an ink introduction hole is provided substantially at the center of the inside of the refill, and a check ball 18 loosely fitted in a valve chamber formed by the axial rear end of the chip 20 and the receiving seat is usually used. A writing implement having a ball-point pen refill with a structure in which the ink flows from the ink storage section to the ball to be the writing section during writing, and the check ball 18 is in close contact with the receiving seat to prevent the backflow of ink upward. It is.

[0006] In this ball-point pen, the ink 16 has a lower viscosity than that of an oil-based ball-point pen which is usually used, and has a high viscosity in a static state. It is filled with ink with shear thinning that flows out smoothly,
A grease-like follower 15 for preventing volatilization and outflow of ink and a follower bar 14 for improving stability with time and drop resistance are formed at the rear in the axial direction of the ballpoint pen. The follower rod 14 is a rod of appropriate dimensions made of a material that does not dissolve in the follower 15 such as polypropylene made of a specific gravity floating on the follower 15, but even in the form of a pipe in consideration of design and manufacturability, a cup is formed in consideration of the specific gravity. It may be shaped.

An opaque molded resin tail plug 13 is formed in the rear of the ink storage tube 12 by appropriately forming an undercut or the like to prevent it from coming off and press-fitting. The tail plug 13 is provided with a groove for air replacement. is there. Further, by providing a tip spring 19 for pressing the writing ball with a very small force inside the tip 20, the writing ball and the tip spring 19 are sunk to the rear of the axis by the writing pressure during writing to secure a space necessary for writing. Can be written. When writing is not performed, the ball valve structure is always sealed by the writing ball and the swaged portion of the chip 20, and the effects of preventing ink leakage, preventing air from entering, and preventing ink backflow are exhibited, and the safety of the ballpoint pen is further improved. . Usually, the ink 16
Is a water-soluble ink, which is also advantageous in preventing the ink from volatilizing in a knock-type writing instrument without a cap. The backflow prevention mechanism using the tip spring 19 and the above described backflow prevention mechanism using the ball valve 18 may be used alone or in combination.

The above-mentioned refill is always urged rearward in the axial direction by a spring 22, and its rear end surface is in contact with the front end of the knock rod 7 inside the shaft. Shaft 1 for knock bar 7
A push portion protruding from the rear end face and a protrusion 8 for restricting retraction during storage are integrally formed, and when the pocket is inserted during refill storage, the knock bar may be used even when there is a crowded train or an unintended knock bar 7 is pressed. 7 is a safety piece that cannot be pressed. An elongated hole or the like is formed in the rear end surface of the shaft 1 as appropriate so that the upright portion 4 of the knock bar 7 can be attached or fixed to the shaft cylinder 1. Further, an elastically deformable spring portion 6 is integrally provided inside the shaft 1 of the clip 2 to prevent the clip 2 from being permanently deformed when the clip ball portion is greatly lifted. It has a clip fixing projection 5 to be inserted and fixed in the fixing window 5-a, and in the case of refill replacement, the fixing projection 5 is pushed to release the insertion and fixing with the shaft, so that the built-in component can be taken out. The spring portion 6 of the clip 2 has a structure that also performs elastic deformation when the protrusion 5 is pressed. In use, since the spring portion 6 of the clip 2 is fixed in the shaft 1 so as not to move in the axial direction, the knock bar 7 passes through the spring portion 6 and cooperates with the front locking cylinder 9. A groove 7-a is provided for abutment, and is movable.

FIGS. 5 and 6 show the operation of the projection 10 of the locking cylinder 9, and these will be described in detail. A locking cylinder 9 having a protrusion 10 on the outer diameter side, which is loosely fitted between the knock bar 7 and the front refill so as to be rotatable with respect to the axis, and a locking member that locks the projection 10 of the locking cylinder 9. The clip 2 having the stopper 3 is fixed to the shaft 1 so as to restrict the movement in the axial direction. The shaft 1 is provided with a window at a portion corresponding to the projection 10 of the locking cylinder 9 and the locking portion 3 of the clip 2. The cam slopes 1-a, 1-b, 1-c, 1-d for rotating the locking cylinder 9 when the projection 10 of the locking cylinder 9 abuts on the window and the locking portion of the clip 2. 3 also has a slope 3-a corresponding to the cam slope of the shaft 1.

First, the state in which the projection 10 moves forward by pressing the knock bar 7 from the refill storage state is shown in FIG.
The protrusion 10 advances without rotating along the window of the shaft 1 and pushes up the locking portion 3 of the clip 2 to pass therethrough. At this time, even if the knock bar 7 is further pushed, the projection 10 rotates counterclockwise toward the pen tip from the axis by the cam slope 1-a of the window of the shaft 1. Here, the dimensions may be set so as to restrict rotation without rotating, but it is more stable if the projection 10 has a slope so that it can be corrected even if it slightly approaches the center. In this state, since the pen tip has sufficiently protruded from the shaft 1, when the pressing of the knock bar 7 is released, the protrusion 1 is released as shown in FIG.
When the clip 0 is to be returned to the rear, it is caught by the locking section 3 of the clip 2 and moves rearward while being rotated in the axial direction by the inclined surface 3-a of the locking section 3. By locking the protrusion 10 on the inclined surface 3-a of the clip 2 with a U-shaped portion, the writing portion of the refill is held in a protruding state and can be written.

Referring again to FIGS. 6C to 6F, the knock bar 7 is normally further pressed to change the refill projecting state to the refill storing state. Then, the projection 10 moves substantially forward from the axial center, contacts the inclined surface 1-b of the shaft 1, and rotates rightward. Here, when the pressing of the knock bar 7 is stopped, the projection 10 moves rearward through a passing portion that is not locked by the locking portion 3 of the clip 2. Here, the refill is stored, but the projection 10 is rotated and moved backward to a predetermined initial position by the slope 1-c of the window of the shaft 1.

The present invention provides, in addition to the above-described embodiments, a so-called water-based ballpoint pen using a batting, which is a fiber bundle, as a so-called water-based ink, and an oil-based ballpoint pen using a highly viscous oil-based ink. Also, a knock-type writing instrument using a refill such as a so-called felt-tip pen or marker using a fiber bundle at the pen tip or a capillary phenomenon inside, a product formed integrally with a clip and a shaft, and a spring property of the clip are further improved. A material in which a metal spring plate is added to the elastically deformable spring portion of the clip or a material in which the locking cylinder and the refill are integrated for reinforcement can be appropriately adopted, and the same effects as those of the present invention can be expected.

[0013]

The operation of the present invention will be described in an embodiment. A knock-type writing instrument that allows writing by pushing a refill of a ballpoint pen from the tip of the shaft by pressing a knock bar that projects backward from the shaft. Since the protruding part of the operating locking cylinder is locked to maintain the protruding state of the refill, when the clip ball is lifted, the locking is released and the refill is automatically stored, so the writing part comes out. It is possible to prevent the clothes from being stained even if the user puts them in their pockets. In addition, since the refill can be repeatedly projected and stored simply by pressing the knock bar, the writing part can be moved in and out like a conventional knock-type writing implement that can only be released by lifting the clip ball. In this case, there is an advantage that a user who does not know how to use can easily perform trial writing at a store without the trouble of having to change a shaft.

Further, in the case of a neutral ball-point pen, a check ball which can prevent air entrapment and backflow of ink when writing upward and a backflow prevention mechanism having a valve structure are provided with a neutral ballpoint pen. Movement of the ink is prevented by being in close contact with the valve chamber. In most cases, the backflow problem can be solved by adopting such a backflow prevention mechanism.However, the backflow prevention mechanism of a similar valve structure is formed by the ball that is the writing part, the swaged part of the holder that holds it, and the internal spring. In a refill provided with the above or a refill using both of them, the operation of the safe knocking mechanism of the present invention is fully utilized. In most cases, grease-like followers are used in neutral ballpoint pens, but they provide dry-up resistance, impact resistance, air entry resistance, and ink leakage prevention.
By floating the solid follower rod on the follower, various accident prevention effects can be further improved.

A protrusion provided on a spring portion having a shape having elasticity of a clip and a window of a shaft regulate return during storage, and when the user replaces the refill, the protrusion is replaced with a pen tip or the like. With a structure in which return regulation is released by pushing with a sharp object and the refill can be replaced, it is easy to manufacture with an automatic assembly machine, cost reduction by reducing the number of parts can be achieved, and the refill can be achieved. A structure capable of reducing the impact force applied to the refill when the cartridge is stored is also possible, so that accidents such as backflow of ink and air entrapment can be further prevented.

[0016]

The configuration and operation of the knock-type writing instrument according to the present invention are as described above, and only satisfy the function of the highly safe knock-type writing instrument which has the effect of preventing a serious accident such as soiling of clothes. Instead, it is possible to provide an easy-to-use writing instrument that can be easily used by the user. Further, the present invention greatly improves the function of preventing the backflow of a ballpoint pen using ink having shear-thinning properties, and simultaneously solves the problem of appearance. In addition, since these parts consist of only press-fitting work on the axis when assembling with an automatic assembling machine, they can be manufactured more easily than conventional parts, have the effect of reducing the defect rate, and have a great effect at a small cost. It is possible to obtain.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an entire writing instrument according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a rear end portion of the writing instrument according to the embodiment of the present invention.

FIG. 3 is an external view showing a lower side of a writing instrument according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view (AA) of a writing instrument according to an embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a locking operation of a writing instrument according to an embodiment of the present invention.

FIG. 6 is a detail drawing of a locking operation of a writing instrument according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Axis 2 Clip 3 Locking part 4 Standing part 5 Fixing projection 5-a Fixing window 6 Spring part 7 Knock rod 7-a Groove 8 Projection 9 Locking cylinder 10 Projection 11 Metal spring plate 12 Ink containing tube 13 Tail plug 14 Follower rod 15 Follower 16 Ink 17 Joint 18 Ball valve 19 Tip spring 20 Tip 21 Protective sealant 22 Spring

Claims (1)

[Claims] 1. A shaft 1, a refill of a ball-point pen in which a so-called shear-thinning ink and a rear end side of the ink are filled with a grease-like follower, a spring 22 for urging the refill to the rear of the shaft, and a shaft. And a knock bar 7 protruding from a rear end of the shaft. The knock bar 7 is operated by pressing the knock bar 7 so that the refill is interlocked and the writing portion is held in a protruding state from the tip of the shaft. Locking cylinder 9 having projection 10 on the outer periphery in front of rod 7
Is loosely fitted so as to be able to rotate (or laterally move) with respect to the axis as appropriate, the rear portion of the refill is inserted into the locking cylinder 9, and the locking portion 3 is attached to the front end of the clip 2 fixed to the shaft 1.
A window is formed in the outer peripheral portion of the shaft facing the locking portion 3, the projection 10 protrudes from the window, and the window and the locking portion 3 are pressed by the knock bar 7. When the projection 10 comes into contact with the cam slope formed on the front surface, the locking cylinder 9 is rotated, and when the projection 10 is locked to the locking portion 3, the writing portion projects from the tip of the shaft 1. With the pressing operation, the locking cylinder 9 is rotated so that the projection 10 is disengaged from the locking portion 3, so that the writing portion can be immersed from the tip of the shaft 1, and further, the projection 10 is locked to the locking portion 3. In this state, when the front end of the clip 2 is displaced in a direction away from the shaft surface, the projection 10 is detached from the locking portion 3 and the writing portion can be immersed from the tip of the shaft 1. Writing instrument.