JP3444824B2 - Ballpoint pen - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a ball-point pen which allows replacement of refills. 2. Description of the Related Art The applicant of the present invention discloses, in Japanese Utility Model Publication No. 4-52067, a mechanism for preventing ink from flowing back in a ball-point pen provided with a valve chamber into which a ball is loosely fitted. In this device, a required number of protrusions are provided in a valve chamber in which a ball is loosely fitted with a synthetic resin mouth plug to prevent the ball from being pulled out, and a gap formed between the protrusions during writing. And the ink flows to the chip. Further, a ballpoint pen using an ink having a shear thinning viscosity, in which the viscosity is reduced by the rotation of the tip ball during writing and the ink flows out, is known. In general, a ballpoint pen using an ink having shear thinning viscosity has a large amount of outflow of ink (to increase the writing density), and has a large diameter of an ink containing tube to increase the amount of ink loaded. Further, since the viscosity of the ink is smaller than that of the ink of the oil-based ball-point pen, the flow resistance to the ink storage tube is small. Accordingly, ink leakage (ink flows backward at the rear end of the ink storage tube) easily occurs due to the ink's own weight or impact. For this reason, the ink usually moves following the consumption of ink at the time of writing at the rear end of the ink, but a grease-like follower that suppresses the backflow of the ink due to its own weight or impact, and a follower as necessary. A rod is loosely inserted in the follower. However, even when the follower is provided, if the ink immediately below the ball of the chip runs out when writing upward, there is a danger that the ink and the head will be added directly, causing a remarkable backflow and soiling the hands and clothes. Further, since the viscosity of the ink is low and the amount of outflow is large, there is a problem that the ink bleeds (DC) if a gap is formed between the tip ball and the chip holding portion when the tip side is directed downward. In addition, a refill of an aqueous ballpoint pen using an ink storage or ink storage is loaded into a shaft cylinder formed by joining a front shaft and a rear shaft (the rear end of the refill is closed). An O-ring fixed between the tip of the front shaft and an inner hole of a base fixed to the tip has a stepped portion of a middle diameter portion of a refill having a vent at a front end to an O-ring in a state where the vent is not blocked. The tip of the tip and the tip of the base are inserted into the inner hole of the inner cap fixedly provided in the inner hole of the cap, and the outer periphery of the base is closely attached to the insertion opening of the inner cap. An aqueous ballpoint pen is known which is tightly fitted in the inner hole of the inner cap and a small chamber in the space of the base hole in front of the O-ring so as to prevent evaporation of ink and drying of the tip ball portion. SUMMARY OF THE INVENTION An object of the present invention is to use ink having a low viscosity or an ink having a shear-thinning viscosity in which the viscosity is reduced by rotation of a ball during writing and the ink flows out. A ballpoint pen and a refill of an aqueous ballpoint pen using an ink occluding body or an ink reservoir can be interchangeably loaded into a writing implement body composed of the same barrel and cap, and in a ballpoint pen having shear thinning, It is possible to prevent reverse flow of ink caused by upward writing or impact and direct current when the tip side is placed downward, thereby preventing contamination of the inside of the barrel of a ballpoint pen, hands, and clothes. In order to achieve the above object, a ballpoint pen according to the present invention is a ballpoint pen refill having a tip of a ballpoint pen at a front end of a joint and an ink container tube at a rear end. In addition, the ink containing pipe has a low viscosity ink or a high viscosity statically, and the ink has a so-called shear thinning viscosity in which the viscosity is reduced by rotation of the tip ball during writing and the ink flows out. Is filled, and the rear end of the ink is filled with a grease-like follower that can move following the consumption of the ink, and a spring is inserted into the chip inner hole. By pressing the rear end of the tip ball rotatably held therein, the tip ball is brought into close contact with the inner edge of the ball holding portion of the chip so that the outflow of ink can be prevented, and the refill of the ballpoint pen can be prevented. Is fixed to the front end of the front shaft and the front end of the front shaft while the front shaft and the rear shaft are screwed together.
O-ring fixed between the inner hole of
The step of the middle diameter part of the joint is in close contact with the inner hole of the cap.
Seal cap on the rear end of the inner hole of the inner cap fixed to
Is fixed and the tip is inserted when the cap is
Tip ball bites into the seal stopper in a pressed manner and
The outer peripheral portion of the front shaft screw is formed in close contact with the insertion opening of the inner hole portion, and further, an air passage for communicating the rear end of the rifle with the outside air is formed by the screw of the front shaft.
Of the rear shaft joined to the vertical groove provided at the joint and the screw joint
It is formed between surfaces . FIG. 1 and FIG. 2 show an embodiment of the present invention. First, as shown in FIG.
2. Externally composed of a joint 39, an ink storage tube 49, and a tail plug 31. The joint 39 is formed of a synthetic resin by integral molding. A large diameter portion 42, a middle diameter portion 41, and a small diameter portion 40 are formed in the first half, and a shaft portion 48 for crimping to the ink containing tube 49 is formed in the second half. I have. A hole penetrates the shaft center, and a shaft portion 35 behind the tip 32 of the ballpoint pen is crimped to the tip hole of the small diameter portion 40. A valve chamber 43 is provided in contact with the rear end of the shaft 35, and a tapered or spherical ball receiving seat 44 is formed at the rear end of the valve chamber 43. In the embodiment, the chip 32
A valve chamber 43 is provided eccentrically with respect to the axis of the shaft portion 35, and a tapered or spherical ball receiving seat 44 is formed at a rear portion of the valve chamber 43 so as to communicate with a guide hole 46. or,
A groove 44 into which ink can flow is provided on one side of the inner wall of the valve chamber 43.
a is formed. A ball valve 47 is provided in the valve chamber 43.
There is loosely fitted, the ball valve 47 in a state where the tip 32 downward is brought into contact with the state of being biased to the rear end of the shaft portion 35 of the chip, ink that has flowed from the guide hole 46 through the groove 44a and the like in the chip It is configured to flow into.
The valve chamber is provided at the axis of the joint 39, a ball valve is loosely fitted in the valve chamber, and the ink is conducted into the chip in a state where the chip is directed downward. The embodiment has been previously filed by the present applicant. On the other hand, the tip 32 is caulked so that the tip ball 33 is rotatably held with the tip ball 33 substantially in contact with a seat having a channel into which ink can flow. The spring 37 is inserted into the inner hole of the chip 32, the rear end of the shaft portion 44a of the chip is appropriately caulked, and the rear end of the spring 37 is provided so as not to be able to be pulled out. An upright rod portion 38 is formed in front of the spring 37, and the distal end of the rod portion 38 is pressed against the rear end of the tip ball 33. The tip ball 33 is brought into close contact with the inner edge of the ball holding portion (formed by caulking or the like) of the chip 32 by the pressing. As described above, when the tip side is downward, the ball valve 47 abuts against the rear end of the caulking portion 36 in a state where it is biased, and ink flows through the guide hole 46, the valve chamber 43, the groove portion 44a, and the like. To the rear end of the tip ball 33. A cylindrical ink storage tube 49 is pressed against the outer periphery of the shaft portion 48 of the joint 39 by abutting the leading end thereof on the rear end of the large-diameter portion 42, and the inner diameter portion of the ink storage tube 49 is joined by the joint. It communicates with 39 guide holes 46. The ink storage tube 49 is filled with low viscosity ink or statically high viscosity ink 50 which has a viscosity reduced by rotation of the ball during writing and has a shear thinning viscosity which allows the ink to flow out. Then, the rear end of the ink 50 is filled with a grease-like follower 51 which is movable in contact with and following the ink surface as the ink is consumed. Further, a resin-made follower rod 52 is loosely inserted into the follower 51. The follower rod 52 is provided as necessary (the ink container tube is thick, the ink head is large, and the viscosity of the ink is low and the ink head cannot be supported). A tail plug 31 having a ventilation hole 53 communicating with the outside air is crimped to the rear end of the ink storage tube 49. The refill 30 of the ball-point pen is constructed as described above, and is loaded into a shaft cylinder formed by screwing the front shaft 11 and the rear shaft 16 as shown in FIG. First, tip shaft 1
Reference numeral 1 denotes a resin molded product having a screw portion 15 at a rear end thereof.
A vertical groove-shaped air passage 18 is formed at a required portion of the air passage 5, and an air hole 19 communicating with the air passage 18 and connected to outside air when joined to a rear shaft 16 described later is formed. A base 12 is fixed to the front end of the front shaft 11 by screwing or the like with an O-ring 14 made of an elastic body (for example, made of rubber) sandwiched between the front end of the front shaft 11 and the front end of the front shaft 11. A screw tube 17 is crimped to the inner hole of the rear shaft 16 at the front end, and a tail plug 20 is fixed to the rear end of the rear shaft 16 with a fixture 21 located in the inner hole of the rear shaft 16 so as to be fixed. A spring 22 is provided upright at the axis of the tool 21. The refill 30 is inserted into the front shaft 11 so that the tip of the tip 32 protrudes from the front end hole of the base 12, and the rear shaft 16 is screwed to the screw portion 15 of the front shaft 11. At this time, the rear end of the tail plug 31 comes into contact with the front end of the spring 22 so that the refill 30 is urged forward in a pressing manner, and the step 45 of the middle diameter portion of the joint 39 is closely contacted with the O-ring 14 in a circumferential manner. I do. An outer peripheral portion near the rear end of the base 12 has a locking groove 13.
Are formed. The crown 3 is crimped to the rear end hole of the cap 1 by holding the clip 2 between the fixture 4 and the crown 3.
Further, an inner cap 5 having a closed rear end is inserted into the inner hole of the cap 1, and the rear end of the inner cap 5 is crimped to the fixture 4. Front inner hole 7 of inner cap 5
A seal stopper 6 made of a non-liquid-absorbing elastic body (for example, made of rubber) is fixed to the rear end. Further, an insertion hole 8 for the inner hole portion is formed in front of the inner hole portion 7, and an outer cylinder portion 9 is formed outside the insertion hole 8. An inward projection is formed on the inner peripheral surface of the outer cylinder portion 9 near the front end thereof. Is formed. As described above, the front shaft portion of the shaft cylinder loaded with the refill 30 is inserted into the cap 1 and the tip ball 3 is inserted.
3 is pressed into the seal stopper 6 in a biting manner,
The outer peripheral portion of the base 12 is in close contact with the insertion port 8 of the inner cylindrical portion,
The cap 1 is fixed by the engaging portion 10 of the outer cylinder portion elastically engaging with the engaging groove 13 of the base. The tip ball portion is tightly fitted between the inner hole 7 and the inner hole of the base in front of the O-ring 14, but is formed by the air passage 18 and the air hole 19 provided at the joint between the front shaft 11 and the rear shaft 16. Refill 30 tail plug 3
Air flows between the outside air and the rear end of the follower 51 through one ventilation hole 53. By the way, the ventilation hole 19 can be provided by drilling a ventilation hole on the side surface of the front shaft 11 or the rear shaft 16 separately from the embodiment. Also, the joint 39 of the refill 30
If a ventilation groove (not shown) is formed on the peripheral surface of the middle diameter portion 41 to the large diameter portion 42, a ventilation path from the inner hole 7 of the inner cap to the inside of the shaft cylinder through the tip hole of the base 12 is formed. It is also possible. In this case, it is not necessary to form a ventilation hole in the barrel. In the embodiment, the refill 30 is used for the joint 3.
Although the ink container 9 and the ink storage tube 49 are provided separately, they may be formed integrally for convenience of design. In addition, if the ink storage tube 49 is formed of a transparent resin molded product and the tip shaft 11 is formed of a transparent resin molded product, the remaining amount of ink can be seen through. The peripheral surface of the front shaft 11 may be opaquely printed so that only necessary portions can be seen through. First, the refill 30 shown in FIG. 2 shows a state in which the tip 32 is directed upward. At this time, the ball valve 47 comes into close contact with the ball receiving seat 44 of the valve chamber 43 and the guide hole 4 is formed.
6, the ink does not flow backward even if the ink immediately below the tip ball 33 is exhausted by upward writing. Therefore, when the chip 32 is turned downward, the ink can immediately flow out, and the writing is prevented from being flared. (By the way, in the structure without the ball valve, the ink head acts in the backward flow direction in upward writing, so that air is entrapped in the chip, and ink does not immediately follow in downward writing, resulting in blurring. In the state before writing with the chip 32 facing down, the ball valve 47 is in contact with the rear end of the shaft 35 of the chip, and the guide hole 46 is opened. The ink 50 that has entered the valve chamber 43 from the ink storage tube 49 through the guide hole 46 is
a flows into the chip inner hole 34 and is conducted to the rear end of the tip ball 33. In this state, the spring 37
The tip ball 33 is brought into close contact with the inner edge of the chip holding portion by the pressing of the rod shaft portion 38, so that the direct current of the ink 50 is prevented.
Further, since the tip ball 33 is slightly retracted by the writing pressure, a gap is generated and ink can flow out. By writing, the rotation of the tip ball 33 causes the ink to flow out and writing can be performed. A channel (a seat for the tip ball having a plurality of ink inflow grooves penetrating toward the inner hole of the chip) is provided immediately below the tip ball 33, and a rod shaft of a spring 37 is provided in the center hole of the channel. The part 38 penetrates. The ink in the chip is guided directly below the tip ball 33 through the ink inflow groove and the gap between the center hole and the rod shaft. Further, since the tip ball 33 is always in close contact with the inner edge of the tip holding portion, it is possible to prevent handwriting by drying the tip portion. Further, even when upward writing or impact is applied by the cooperative action of the tip ball 33 and the ball valve 47, the entrainment of air is alleviated, so that writing blur is prevented. The direct current and the reverse flow of the ink are fulfilled by the pressing of the tip ball 33 by the spring 37. To cover the incomplete state in the case where solid matter adheres to the gap between the head and the head, and to support the head with a large amount of ink to reliably prevent the backflow of the ink, and to alleviate the air entrainment (prevent from flaring). Spring 37
Collaborate with The configuration and operation of the ballpoint pen of the present invention are as described above. A ballpoint pen refill and an ink occluding material or ink storing material using low viscosity ink or ink having shear thinning property are used. The refill of the used water-based ballpoint pen can be loaded into the common writing instrument body. or,
Since the tip ball is in close contact with the inner edge of the tip holding portion except when writing, direct current is prevented when the ink flows backward or is placed downward, thereby preventing accidents that stain the inside of the barrel, hands, and clothes.
In addition, handwriting due to drying is prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a ballpoint pen according to an embodiment of the present invention, which is partially non-sectional. FIG. 2 is a longitudinal sectional view of a refill of a ballpoint pen used in the present invention, showing a state in which a chip is directed upward. [Description of Signs] 1 Cap 2 Clip 3 Crown 4 Fixture 5 Inner cap 6 Seal plug 7 Inner hole 8 Inner hole insertion port 9 Outer cylinder 10 Locking section 11 Front shaft 12 Cap 13 Lock groove 14 O-ring 15 Screw portion 16 Rear shaft 17 Screw tube 18 Ventilation path 19 Vent hole 20 Tail plug 21 Fixture 22 Spring 30 Refill 31 Tail plug 32 Tip 33 Tip ball 34 Tip bore 35 Shaft portion 36 Caulking portion 37 Spring 38 Rod shaft Portion 39 Joint 40 Small diameter portion 41 Medium diameter portion 42 Large diameter portion 43 Valve chamber 44 Ball receiving seat 44a Groove 45 Step 46 Lead hole 47 Ball valve 48 Shaft 49 Ink storage tube 50 Ink 51 Follower 52 Follower rod 53 Vent hole

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B43K 7/02 B43K 7/08

Claims (1)

(57) [Claims] [Claim 1] A ball-point pen tip is attached to the tip of the joint,
In the refill of a ball-point pen having an ink storage tube at the rear end, the ink storage tube has low viscosity ink or static high viscosity, and the viscosity decreases by rotation of the tip ball during writing. The ink is discharged, and the ink is filled with a so-called shear thinning ink, and the rear end of the ink is filled with a grease-like follower that can move following the consumption of the ink. A spring is inserted, and the rear end of the tip ball rotatably held at the tip of the tip is pressed by the tip of the spring. Outflow can be prevented, and the refill of the ballpoint pen is loaded into a shaft cylinder formed by screwing the front shaft and the rear shaft together, and the front end of the front shaft and the inner hole of the base fixed to the front end of the front shaft.
O-ring fixed in between the refills
The step of the diameter part is in close contact with the
A seal plug is fixed to the rear end of the
The tip of the tip when the cap is fitted to the tip shaft.
The tool bites into the seal stopper in a pressing manner and the outer periphery of the base
Is formed in close contact with the insertion opening of the inner hole, and furthermore, an air passage for communicating the rear end of the refill and the outside air is formed in the screw joint of the front shaft.
Between the vertical groove provided and the inner surface of the rear shaft joined to the screw joint
Ballpoint pen being characterized in that formed on.