JPH10138686A - Dual writing utensil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To selectively protrude/retract the writing tips of respective writing utensils from the leading end of a shaft cylinder by a method wherein the connected area between the tip of an ink housing tube and the ink housing part is made flexibly deformable so that the tip may be easily concentered to the leading end port of the shaft cylinder. SOLUTION: The ink housing part of an ink housing tube 17 is formed into a non-deformable part having a comparatively large cross sectional area, and the cross sectional shape is formed into an approx. D-shape which can be fitted in a rear shaft 30 without a waste. Also, the connected area between a joint 2 which presses the rear end of a tip 11 and the ink housing part, is made easily deformable in the lateral direction to the longitudinal direction of the shaft. In this case, when an operational body 40 is turned in one direction to the rear shaft 30, the protruding parts 43a, 43b of sliding elements 42a, 42b slide along a cam groove 35 accompanying the rotation of a rotating shaft 33, and either one of the sliding elements advances, and the other element retracts, and the writing leading end part of a writing utensil on the advancing side, is projected from the leading end port of the front shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a ballpoint pen writing material which is filled with at least one water-based (medium-viscosity) or low-viscosity oil-based ballpoint pen ink having shear thinning properties.
The present invention relates to a double-type writing implement including a plurality of types of writing objects, each of which is arbitrarily combined with a writing object such as a normal oil-based ballpoint pen and a mechanical pencil writing object.

[0002]

2. Description of the Related Art In general, there has been known a double-type writing instrument having a plurality of writing objects such as a ball-point pen mounted thereon so that a writing tip can be selectively protruded and retracted from an axis. In addition, as a retracting mechanism of the writing tip portion of the double-type writing instrument, a knocking type, a slider type that alternately slides a slider protruding from the side of the shaft cylinder of the writing instrument, and a cam cylinder having an inclined surface are rotated. Various types such as a cam type are known. The conventional retracting mechanism has a built-in return spring for returning the writing body to the inside of the barrel, so the structure is complicated and the number of parts is large,
There is a problem of high cost. Further, the space for incorporating the mechanism is large, and the degree of freedom of the refill shape is small.

On the other hand, when a medium-viscosity water-based and low-viscosity oil-based ballpoint pen is mounted on a double-sized writing instrument having a normal thickness due to a large ink container tube, the tip of the writing body protrudes without freedom between the writing bodies. The part is not smoothly centered on the tip hole of the barrel, and the operation is hindered, so that the writing tip cannot appear or disappear.
Therefore, there is a disadvantage that the shaft cylinder becomes extremely thick to enable the operation, and the portability and the usability are deteriorated.

[0004] Aqueous ballpoint pens have a low viscosity of several mPa · S or less, and therefore have the advantage of being able to be written with a light writing pressure, and are characterized by good writing taste. However, there is a drawback that a DC phenomenon in which the ink flows slowly from the pen tip, and a reverse flow phenomenon in which the air flows in from the tip of the ballpoint pen and the ink flows out, are likely to occur. A method of preventing these phenomena by using a fiber convergence material called batting is used. Also, if left in a cap-off state, there is a problem that the vapor pressure of the solvent is high and the solvent is leaked, so that the tip is dried and the ink does not flow out, making it impossible to write.

On the other hand, conventionally known oil-based ballpoint pens have a high viscosity of several thousands mPa · S or more of ink, so that the resistance to the rotation of the ball when the ink flows out of the pen tip is high. There is a drawback that writing is bad because of large size. In addition, there is a problem in that the amount of ink flowing out from the tip during writing is small, there is a dent phenomenon, the writing line is uneven, the writing density is low, and a high writing pressure is required. As an improvement of the oil-based ballpoint pen, recently, an intermediate viscosity region (a few mPa · S to a few thousand mP) between the above-mentioned water and oiliness
Ballpoint pens for aqueous inks called medium viscosity using the inks of a · S) have been developed. This is a ballpoint pen using a relatively low-viscosity water-based ink having a characteristic of lowering the viscosity by the rotation of the tip ball and smoothly flowing out the ink, that is, a so-called shear thinning property. However, since this ink has a drawback that the ink easily dries, a cap for sealing the writing tip is usually required.
In addition, the amount of outflow of ink is increased, and it is necessary to increase the diameter of the ink storage tube and increase the amount of ink to be filled in order to extend the writing life.

As an improvement of the oil-based ball-point pen, a ball-point pen using a low-viscosity oil-based ink having excellent drying resistance can be considered. However, the amount of the ink flowing out is increased, and the ink storage tube is required to extend the writing life. It is necessary to increase the diameter of the ink and increase the filling amount of the ink. Also, due to the low viscosity of the ink, if the tip side faces downward and there is a gap between the tip ball and the tip holding portion, the ink will bleed (DC) or the amount of ink flowing out during writing will increase. There are drawbacks.

[0007] Since both the above-mentioned medium-viscosity aqueous ink and low-viscosity oil-based ink have low viscosities, there is a phenomenon that the ink easily flows backward or direct current. If the ink causes backflow or direct current, there is a risk of soiling clothes and the like. In addition, there is a drawback that handwriting is apt to occur due to drop or knock impact. In addition, a medium-viscosity aqueous ball-point pen is usually filled with a grease-like translucent non-drying substance called a follower at the rear end of an ink storage tube. What is necessary is just to consider the reduction of evaporation from the gap. For example, if a solvent having a considerably low vapor pressure, such as an oil-based ballpoint pen, is mainly used, evaporation of the ink need not be considered. However, in the case of water-based ink, since water is the main solvent, evaporation of water cannot be prevented only by selecting a low vapor pressure solvent.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, that is, to mount a plurality of writing bodies in a barrel and write the respective writing bodies from the tip of the barrel. An object of the present invention is to provide a double-type writing instrument that allows the tip to selectively appear and disappear, and is excellent in manufacturing cost, portability, and usability. In addition, there is no backflow of ink and no direct current phenomenon, and the drying resistance of the pen tip is maintained, so that the pen tip can be left without a cap, and a mechanism to prevent dropping impact, reverse flow of ink due to upward writing, and direct current of ink. Comprising a writing body of a medium-viscosity aqueous, low-viscosity oil-based ball-point pen having at least one ball-point pen writing body, a plurality of writing bodies mounted in the barrel,
An object of the present invention is to provide a convenient dual-purpose writing instrument that selectively protrudes and retracts a writing tip of each writing body from a tip of a barrel. Still another object of the present invention is to avoid the danger of soiling clothes by inserting the writing tip of the writing pen of the ballpoint pen into a pocket or the like with the writing tip protruding.

[0009]

According to the present invention, there is provided a writing instrument comprising:
The tip ball has a spring provided so that the tip ball always presses and closely contacts the inner edge of the ball holding portion at the tip end, and has a spring provided so that the close state is released during writing. A valve chamber into which the valve is loosely fitted is provided, and a ball receiving seat for preventing a backflow of ink due to the close contact of a ball valve at the rear of the valve chamber, and a guide hole leading from the ball receiving seat to the ink receiving pipe are provided. In addition, a non-deformable ink storage tube having a relatively large cross-sectional area in the ink storage portion, and a connecting portion between the tip of the ink storage tube and the ink storage portion can be flexibly deformed. The ball is filled with an aqueous ballpoint pen ink or so-called low-viscosity oil-based ink that has a so-called shear-thinning viscosity, and the viscosity of the ink is reduced by the rotation of the tip ball. Ballpoint pen writing body composed of a grease-like translucent non-drying substance that moves and is filled with a plurality of types of writing bodies including at least one ballpoint pen writing body. The tip is easily centered at the tip end of the barrel even if the tip is disposed in the barrel so as not to swing substantially, so that the tip end smoothly comes out of the tip end of the barrel. In addition, a clip is provided on the outer peripheral side surface of the front end of the shaft cylinder, and even if the tip is protruded, the tip is inserted upward into the pocket, so that the danger of soiling clothes is avoided.

[0010] In addition, at least one of the above ballpoint pen writing materials
As a double-type writing instrument equipped with two types of writing objects including books,
A front shaft, a rear shaft, a rotary shaft having a cam groove formed in a shaft peripheral surface and being rotatably disposed in an inner hole of the rear shaft in a range of approximately 180 degrees with respect to the rear shaft; The operating body fixed to the rear end of the rotating shaft protruding at the end, and the operating body and the rotating shaft are rotatably held with respect to the rear shaft, and the projections that engage with the cam grooves of the rotating shaft face each other. A pair of sliding pieces formed on the inside of the rear shaft are guided by the inner hole of the rear shaft so as to be able to move only forward and backward, and respective writing bodies are provided in front of the respective sliding pieces so as to interlock with the sliding pieces. Each sliding piece is alternately moved back and forth by the rotation of the rotating shaft accompanying the rotation of the operating body, so that the writing tip of each writing body can be protruded and retracted from the front shaft tip opening. .

A center shaft provided between the front shaft and the rear shaft;
A rotation shaft disposed in a rear inner hole of the center shaft so as to be rotatable within a range of approximately 180 degrees with respect to the center shaft, fixed to the rear shaft, and having a projection formed forward; and a projection of the rotation shaft. A pair of sliding pieces formed on the inner side opposed to each other with an inclined cam groove are guided by the inner hole of the center shaft so as to be able to move only forward and backward, and a sliding piece is provided in front of each sliding piece. Two kinds of writing bodies are provided so as to be interlocked with each other, and the rotation of the rotating shaft accompanying the rotation of the rear shaft causes the sliding piece to move back and forth, so that the writing tip can be protruded and retracted from the front shaft tip hole. Consisting of

[0012]

1 to 6 show a first embodiment of the present invention. In FIG. 1, two ballpoint pen writing bodies 1a and 1b are provided. The dual writing implement intended by the present invention is a ballpoint pen writing body filled with an aqueous or low-viscosity oil-based ballpoint pen ink having a so-called shear thinning property, and at least one is a common oil-based ballpoint pen writing body, a mechanical pencil. Cursive and the like are used in combination as needed.

The writing instrument of FIG. 1 comprises a front shaft 45 and a rear shaft 30 for accommodating a portion of a writing instrument mechanism located at a front portion, and an operating body 40 disposed at a rear end of the rear shaft. Also, the front shaft 45
A clip 47 connected to a base portion 47a is formed on the outer peripheral side surface slightly behind the distal end opening. A female screw 46 is formed on the inner periphery of the rear part of the front shaft 45. The shaft cylinder is composed of a front shaft and a rear shaft, and in the case where it is not necessary to replace the cursive writing, the front shaft and the rear shaft become an integral shaft cylinder. A male screw 32 is formed at a front portion of the rear shaft 30 and is screwed with the female screw 46 of the front shaft 45, and is removed as necessary to exchange a writing body. A detent rib 30a is provided on the inner periphery of the rear end of the inner hole of the rear shaft 30 for restricting a rotation range of a rotary shaft 33 described later.
Are formed and have a stepped portion 30b, and are formed in the front inner peripheral portion of the rear shaft 30 at intervals of 90 degrees in the axial direction.
A book guide rib 31 is formed.

The rotating shaft 33 has a small diameter portion 3 in front of the large diameter portion 36.
The spiral cam groove 35 is formed on the peripheral surface of the small diameter portion 34. In addition, a shaft portion having a reduced diameter is provided behind the large-diameter portion 36, and a protruding locking portion 37 is provided on an outer periphery in front of the shaft portion.
A detent groove 38 is provided at a required position at the rear end.
A groove 36a is formed on the peripheral surface of the large-diameter portion 36 so that the rib 30a engages with the rear shaft 30 to regulate the rotation of the rotation shaft 33 in a range of usually 120 to 180 degrees. . It should be noted that increasing the rotation angle of the rotation shaft 33 has the advantage that the rotation resistance is reduced and the operation is easy, but the point that the action is increased by increasing the rotation angle is a disadvantage in operation. Therefore, the rotation angle is selected closer to 180 degrees when the diameter of the shaft body is small, and closer to 120 degrees when the diameter of the shaft body is large.

The operation body 40 has a hole 41 in front of the crown 41.
As for a, a peripheral locking groove 41b is provided on the front peripheral surface of the hole and a rotation stop rib 39 at a required portion is provided on the rear peripheral surface. still,
It is easy in design to form the operating body 40 and the rotating shaft 33 integrally and attach them to the rear end of the rear shaft 30.

Insertion holes 44a and 44b are provided in front of the sliding pieces 42a and 42b, and in the respective insertion holes, engagement portions of inward protrusions for fixing rear ends of ballpoint pen writing bodies 1a and 1b described later. 48a and 48b are provided. Also, on the rear inner surface side, projections 43a, 4 for each sliding piece to move back and forth by the pressing of the cam groove 35 due to the rotation of the rotating shaft 33.
3b is formed. Grooves 49a and 49b are provided on the outer circumference of the sliding pieces 42a and 42b so as to stop and engage with the guide ribs 31 of the rear shaft 30. Therefore, the grooves 49a provided on the side surfaces of the sliding pieces 42a and 42b,
The engagement of the ribs 49b with the guide ribs 31 causes the sliding pieces 42a, 42b to smoothly move back and forth.
The cross-sectional shape of the sliding pieces 42a and 42b is substantially D-shaped. Therefore, there is an advantage that a complicated structure for mounting a guide cylinder having two opposing guide grooves, which is often shown in the conventional example, is not required. Also, the sliding pieces 42a, 42
b, the flat sides thereof are in contact with each other, but in order to make the sliding between them smoother, the guide pieces 50b are provided on the sliding pieces 42b.
However, the sliding piece 42a is provided with a guide groove 50a into which the guide protrusion 50b is inserted.

The rotating shaft 33 is connected to the sliding piece 42.
The projections 43a and 43b of the a and 42b are inserted into the inner hole of the rear shaft 30 while being engaged with the cam groove 35, and the rear end of the large-diameter portion 36 abuts on the step 30b of the rear shaft. Rotating shaft 33
The operating body 40 is fixed to the rear end shaft portion. At this time, the locking portion 37 is engaged with the locking groove 41b of the crown 41, the rotation stopping groove 38 is engaged with the rotation stopping rib 39 of the crown, and the rotating shaft 33 and the operating body 40 are integrally fixed. Then, by rotating the operating body 40 with respect to the rear shaft 30, the rotating shaft 33 rotates, with which one sliding piece moves forward and the other sliding piece moves backward. Also, the insertion holes 44a, 4b of the sliding pieces 42a, 42b are provided.
The rear ends of the ball-point pen writing bodies 1a and 1b are fixed to 4b, and the front shaft 45 is fixed in front of the rear shaft 30. By the way, when one of the cursive writings is a mechanical pencil, a configuration in which the operating body 40 is shifted with respect to the rear shaft 30 is necessary. However, such a configuration in which a spring is biased between the operating shafts is designed. It is easy.

Next, the ballpoint pen writing body 1a mounted on the double-type writing instrument of the present invention will be described. Note that the ballpoint pen writing bodies 1a and 1b have the same configuration, for example, different ink colors and writing lines. The ink applied to the ballpoint pen writing material is a water-based, low-viscosity oil-based ink having a so-called shear thinning property.

As shown in FIG. 6, the tip 11 is caulked so that the tip ball 12 is rotatably held with the tip ball 12 substantially in contact with a seat having a channel into which ink can flow. . A spring 14 is inserted into the inner hole of the chip 11, and the rear end of the shaft 13 of the chip is appropriately caulked so that the rear end of the spring 14 cannot be pulled out. In addition, it is extremely important that the tip ball 12 is in close contact with the inner surface of the tip holding portion in order to dry the writing tip and to prevent direct current of ink. Therefore, the surface roughness of the tip holding the tip ball and the caulking In order to improve the close contact accuracy, grinding of the inner surface and secondary plastic working to increase the crimping accuracy are considered. In addition, a surface treatment or the like is taken into consideration for the surface in close contact with the tip ball.

Further, the tip of the spring 14 is a straight rod portion 15, and the tip of the rod portion 15 is
Abuts on the rear end of the device in a pressed state. The tip ball 12 is brought into close contact with the inner edge of the ball holding portion (formed by caulking or the like) of the chip 11 by the pressing.

Further, the joint 2 has a shaft 1
A front shaft portion 3 for pressing the third shaft 3 and a rear shaft portion 5 to be pressed against the front end of the ink storage tube 17 are formed, and the space between the front shaft portion 3 and the rear shaft portion 5 is flexible. It is formed of a resin molded product integrally connected by a bendable portion 4 or the like. Further, a valve chamber 7 in which a ball valve 16 is loosely fitted is provided behind the inner hole of the front shaft section 3, and a tapered or spherical ball receiving seat 8 is provided behind the valve chamber 7 and a ball receiving seat 8. An eccentrically provided guide hole 9 is provided, and the bendable portion 4 and the rear shaft portion 5 are provided.
Communicates with the inner hole of the ink storage tube 17. or,
A groove is provided on one side of the inner wall of the valve chamber 7 so that ink flows in the axial direction. When the tip 11 is turned downward, the loosely fitted ball valve 16 in the valve chamber 7 is in contact with the tip end of the shaft portion 13 of the tip, and forms an ink flow path. Ink passes through the guide hole 9 and the groove portion,
It flows into the chip inner hole through the ink flow path or the like. On the other hand, in the upward state, the ball valve 16 comes into contact with the ball receiving seat 8 to obtain a function of preventing the ink from flowing backward.

The ink container tube 17 is filled with the ink 18 of the above-mentioned ball-point pen, and the rear end of the ink 18 is a grease-like half that can move following the ink surface as the ink is consumed. A follower 19 made of a transparent non-drying substance is filled. Further, a resin follower rod 20 having a specific gravity substantially equal to that of the follower 19 is immersed in the follower 19 as necessary in order to prevent deformation due to dropping, knock impact or the like. A tail plug 21 is fixed to the rear end of the ink storage tube 17.
a, locking portion 48 of insertion hole provided in front of 42b
a, 48b are provided with locking grooves 23 for detachably fastening. The tail plug 21 is provided with a ventilation groove 22 for communicating the inside of the ink storage tube 17 with the outside air. The ink storage tube 17 is made of, for example, a transparent PP resin molded product. Further, the ink container 17 is selected from a material having excellent clear drain properties. Further, the ink storage tube may be formed integrally with the joint 2.

Further, the ink storage portion of the ink storage tube 17 is a non-deformed one having a relatively large cross-sectional area. In the embodiment, the ink storage portion has a substantially D-shaped cross-sectional shape which can be inserted into the rear shaft 30 without waste. Have. The portion connecting the tip 11 and the ink storage portion can be easily shifted in the lateral direction with respect to the axial direction. It is also possible to connect a flexible tube between the joint for crimping the rear end of the chip 11 and the ink containing tube.

First, FIGS. 7 to 10 show a second embodiment of the present invention. Hereinafter, only differences from the first embodiment will be described. 7 includes a front shaft 73 and a middle shaft 60 that house a portion of the writing tool mechanism located at the front, and a rear shaft 69 located at the rear. A female screw 74 is formed on the rear inner periphery of the front shaft 73. The shaft cylinder is composed of a front shaft and a center shaft. A male screw 62 is formed at the front of the front end of the center shaft 60, is screwed with the female screw 74 of the front shaft 73, and is removed as necessary to replace the writing body. Also, four guide ribs 61 formed in the axial direction at 90-degree intervals are formed on the inner peripheral portion of the center shaft 60, and a step portion 60a is formed on the inner peripheral rear end portion.

The rotary shaft 63 is rotatably disposed on the inner peripheral rear portion of the central shaft 60 with the rear end of the large diameter portion 66 abutting on the step portion 60a. The shaft 69 is fitted. At this time, the detent rib 71 provided on the rear hole 70 of the rear shaft 69 and the detent groove 68 provided on the shaft extending rearward of the large-diameter portion 66 are engaged with each other and formed on the rear part. The locking portion 67 is locked to the rear end of the rear shaft 69 so as to be integrated with the rear shaft 69, and the rear shaft 69 is rotatably stopped with respect to the center shaft 60.

Further, a projection 65 is provided in front of the small diameter portion 64 of the rotary shaft 63, and the projection 65 is provided with a sliding piece 76 to be described later.
a and 76b are engaged with the cam grooves 77a and 77b. or,
The rotation shaft 63 is approximately 120 to 180 between the rotation shaft 63 and the center shaft 60.
There are regulating portions between each other so as to regulate the rotation within a range of degrees. (Not shown) The operating body described in the claims points to the rear shaft.
Further, it is possible to design such that the rear shaft, the rotating shaft, and the crown are integrally formed and attached to the center shaft.

Mounting holes 78a, 78b are provided in front of the sliding pieces 76a, 76b, and ballpoint pen writing bodies 1a, 1b are mounted therein. Cam grooves 77a and 77b are formed on the inner side for the sliding piece to move back and forth by the pressing of the portion 65. Also, the grooves 79a, 79b provided on the outer surface of the sliding pieces 76a, 76b engage with the guide ribs 61 provided on the inner peripheral portion of the center shaft 60, respectively.
76b is smoothly moved back and forth. Also, sliding pieces 76a, 7
The cross-sectional shape of 6b is substantially D-shaped. Therefore, there is an advantage that a complicated structure for mounting a guide cylinder having two opposing guide grooves, which is often shown in the conventional example, is not required. A crown 82 is attached to the rear end of the rear shaft 69 to hide the locking portion 67 of the rotating shaft.

[0028]

First, the first embodiment will be described. Rear shaft 3
When the operating body 40 is rotated to one side with respect to
The protrusions 43a and 43b of the base members 2a and 42b slide along the cam groove 35 with the rotation of the rotating shaft 33, so that one of the sliding pieces moves forward, and the other slides backward, and the writing element of the forward-side writing body is moved. The writing tip can be made to protrude from the tip end of the tip shaft 49. Further, even if the ink storage portion of the ballpoint pen writing body is not deformed, the writing tip portion flexibly shifts, so that the operation is not hindered and the writing tip portion smoothly comes out of the tip end of the front shaft 45.

When the rotary shaft 33 is rotated, the sliding piece 42a is retracted, and the writing tip of the ballpoint pen writing body 1a is
And the sliding piece 42b moves forward. When the rotating shaft 33 is further rotated, the sliding piece 42a further retreats,
The sliding piece 42b further advances, and the writing tip of the writing pen 1b protrudes from the tip end of the front shaft 45. FIG.
The contact portion 36c of the groove 36a of the large-diameter portion 36 of the rotary shaft shown in FIG.

In a state where the tip 11 is turned upward, the ball valve 16 is positioned in the ball receiving seat 8 of the valve chamber 7 and seals the guide hole 9 in the ballpoint pen writing body 1a. Even if the ink on the back surface of the tip ball 12 runs out, the ink is caught by the head and does not flow backward. Therefore, when the chip 11 is turned downward, the ink can immediately flow out, and the writing is prevented from being rubbed. (By the way, in the structure without a ball valve, the ink acts in the reverse flow direction by writing upward, so air is trapped in the chip,
Ink does not immediately follow with downward writing, causing rubbing)

In the writing state in which the chip 11 is directed downward, the ball valve 16 abuts on one of the rear ends of the chip 11 in a biased state, and the other side has a flow path through which ink can flow into the chip 11. Then, the ink 18 that has entered the valve chamber 7 from the ink storage tube 17 through the guide hole 9 is guided to the back of the tip ball 12. In this state, the tip ball 12 is brought into close contact with the inner edge of the chip holding portion by the pressing of the rod shaft portion 15, so that the direct current of the ink is prevented. In addition, the tip ball 12 slightly retreats due to the writing pressure, so that a gap is created and ink can flow out. By writing, the rotation of the tip ball 12 allows the ink to flow smoothly, and there is no dent and writing with high handwriting density is possible. Becomes A channel (a receiving seat for the tip ball having a plurality of ink inflow grooves penetrating toward the inner hole of the chip) is provided on the back surface of the tip ball 12, and a rod shaft portion 15 passes through a center hole of the channel. The ink in the chip is guided to the back of the tip ball 12 through the ink inflow groove and the gap between the center hole and the rod shaft portion 15.

[0032]

As described above, the composition and operation of the dual writing instrument of the present invention are as described above. The ink does not flow backward, the DC phenomenon does not occur, the drying resistance of the pen tip is maintained, and the cap can be left without the cap. In addition, a plurality of types of ballpoint pens having at least one ballpoint pen using water-based, low-viscosity oil-based ink having a so-called shear thinning property capable of preventing drop impact, backflow of ink due to upward writing and direct current of ink can be prevented. A double-type writing instrument with a cursive body mounted inside the barrel and the writing tip of each cursive body can be selectively protruded and retracted from the barrel barrel tip can be provided in a shaft body thickness that satisfies portability and usability. Becomes In addition, since the clip is provided on the outer side of the forward end of the barrel, the tip of the tip faces upward when the clip is inserted into the pocket, so that the danger of soiling clothes can be avoided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the entirety of a double-type writing instrument according to a first embodiment of the present invention, which is partially not shown in section. 2
It has a kind of ballpoint pen cursive.

FIG. 2 is an external view of a state in which a writing tip is stored.

FIG. 3 is a cross-sectional view taken along the line CC in FIG. 1, but shows a state in which a writing body is not fixed to the sliding piece 42a.

FIG. 4 is a sectional view taken along the line BB in FIG. 1; or,
The position of the clip accompanying rotation of the operating body is shown.

FIG. 5 is a sectional view taken along the line AA in FIG. 1;

FIG. 6 is a longitudinal sectional view of the ballpoint pen writing body 1a.

FIG. 7 is a longitudinal sectional view showing the entirety of a double-type writing instrument according to a second embodiment of the present invention, which is partially shown in a non-sectional view. 2
It has a kind of ballpoint pen cursive.

FIG. 8 is a cross-sectional view of a sliding piece portion located on the center shaft.

FIG. 9 is a cross-sectional view of the ink storage portion of the ballpoint pen writing body located at the center axis.

FIG. 10 is a perspective view showing shapes of a rotating shaft and a sliding piece.

[Explanation of symbols]

 1a Ballpoint pen writing body 1b Ballpoint pen writing body 2 Joint 3 Front shaft part 4 Bendable part 5 Rear shaft part 6 Flange part 7 Valve room 8 Ball receiving seat 9 Guide hole 10 Inner hole part 11 Chip 12 Tip ball 13 Shaft part 14 Spring 15 Rod shaft part 16 Ball valve 17 Ink storage tube 18 Ink 19 Follower 20 Follower rod 21 Tail plug 22 Vent groove 23 Locking groove 30 Rear shaft 30a Rib 30b Step 31 Rib for guide 32 Male screw 33 Rotating shaft 34 Small diameter portion 35 Cam groove 36 Large diameter portion 36a Groove 36b Contact portion 36c Contact portion 37 Locking portion 38 Detent groove 39 Detent rib 41a Hole 41b Lock groove 42a Sliding piece 42b Sliding piece 43a Projecting part 43b Projecting part 44a Insertion hole 44b Insertion hole 45 Front shaft 46 Female screw 47 Clip 47a Base 48a Locking portion 48b Locking portion 49a Groove 49b Groove 50a Guide groove 50b Guide protrusion 60 Center shaft 61 Guide rib 62 Male screw 63 Rotating shaft 64 Small diameter portion 65 Projection 66 Large diameter portion 67 Locking portion 68 Detent groove 69 Rear shaft 70 Back hole 71 Stop rib 72 Top crown 73 Front shaft 74 Female screw 75 Clip 76a Sliding piece 76b Sliding piece 77a Cam groove 77b Cam groove 78a Mounting hole 78b Mounting hole 79a Groove 79b Groove

Claims (4)

[Claims] 1. A tip comprising a spring provided so that the tip ball always presses and contacts the inner edge of the ball holding portion at the tip of the tip, and releases the contact when writing. A water-based ballpoint pen ink or a low-viscosity oil-based ink having a so-called shear-thinning viscosity is filled into the ink storage tube, the viscosity of which is reduced by the rotation of the tip ball accompanying writing, and the ink is filled into the ink storage tube. A ballpoint pen writing body having a trailing end filled with a grease-like translucent non-drying substance that moves following consumption of ink accompanying writing, and a plurality of writings including at least one ballpoint pen writing body A double writing implement comprising a mechanism for mounting a body and allowing a tip end of each writing body to be selectively protruded and retracted from a tip end of a barrel in conjunction with the writing body; The ink container of the vessel has a relatively large cross-sectional shape and is arranged in the shaft cylinder in a state that does not substantially swing, and ink is stored so that the tip is easily centered at the tip end of the shaft cylinder. A compound writing instrument in which a connection portion between a tip of a tube and an ink storage portion is flexibly deformable, and a clip is provided on a side surface of an outer peripheral portion on a tip end of the barrel. 2. A ball-point pen having a ball chamber in which a ball valve is loosely fitted in contact with a rear end of a tip, and a ball valve is in close contact with a rear portion of the valve chamber to prevent backflow of ink. 2. The dual writing implement according to claim 1, wherein a guide hole is provided from the seat and the ball receiving seat to the ink storage tube. 3. A rotary shaft having a cam groove formed in a shaft peripheral surface and being disposed in a rear inner hole of the shaft cylinder so as to be rotatable within a range of approximately 180 degrees with respect to the shaft cylinder, and a rear end of the shaft cylinder. An operating body fixed integrally or separately to the rear end of the protruding rotary shaft, and a protruding portion that is rotatably held with respect to the shaft cylinder and engages with the cam groove of the rotary shaft are opposed to each other. A pair of sliding pieces formed on the inner side are guided by the inner hole of the barrel so as to be able to move only in the forward and backward directions, and respective writing bodies are provided in front of the respective sliding pieces so as to interlock with the sliding pieces. The rotation of the rotating shaft accompanying the rotation of the operating body causes each sliding piece to alternately move back and forth so that the writing tip of each writing body can be protruded and retracted from the tip opening of the barrel. 3. The double-type writing instrument according to claim 1, wherein the writing instrument is a multi-functional writing instrument. 4. A rotating shaft provided in a rear inner hole of the barrel so as to be rotatable within a range of approximately 180 degrees with respect to the barrel, and having a projection formed in front of the shaft peripheral surface, and a rear end of the barrel. An operating body fixed integrally or separately to the operating body, and the operating body is rotatably held with respect to the shaft cylinder, and inclined cam grooves engaging with the protrusions of the rotating shaft are formed on the inside facing each other. A pair of sliding pieces are guided in the inner hole of the barrel so as to be able to move only in the forward and backward directions, and each writing body is provided in front of each sliding piece so as to interlock with the sliding piece, so that the operating body can be rotated. 2. The method according to claim 1, wherein the sliding top is alternately moved back and forth by the rotation of the rotating shaft so that the writing end of each writing body can be protruded and retracted from the end opening of the barrel. 2. The double-type writing implement according to 2.