JPH1159056A - Refill for ballpoint pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent backflow of ink by engaging a ball valve loose with a valve chamber formed at a ball seat and filling oily ink in an ink containing tube. SOLUTION: In the case of disposing a tip 8 upward state, a ball valve 13 is disposed at a ball seat 5 of a valve chamber 7 to close a guide hole 6. Then, in the case of upward writing, ink is lost behind a point ball 12 of the tip, but the ink is blocked by a head so as not to flow reversely. At the time of downward writing by directing the tip 8 downward, the ink can flop out. In the case of writing downward with the tip 8 directed downward, the valve 13 is brought into contact with protruding strips 4, and hence the ink 14 fed from an ink containing tube 2 to the chamber 7 via the hole 6 flows into the chip 8 via a gap formed between the strips. And, channels 10 (the seat of the point ball having a plurality of ink supply grooves) are provide on the back surface of the ball 12, and an ink guide hole is penetrated at a center of the channels 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-based ball-point pen having a mechanism for preventing ink from flowing back.

[0002]

2. Description of the Related Art Conventionally, oil-based ballpoint pens have problems such as ink flowing backward due to a decrease in viscosity due to a rise in temperature and upward writing, and the like, making writing impossible and causing leakage of ink to stain the surroundings. In order to prevent the backflow of the ink, various measures have been taken such as reducing the size of an ink guide hole provided in the chip or changing the composition of the ink. There is also a backflow preventing agent provided on the rear end surface of the ink or a plug provided at the rear end of the ink storage tube to prevent the leakage of the ink. However, once the backflow occurs, the problem that writing becomes impossible cannot be solved. . In addition, a valve chamber is provided at the tip end position of the chip for a long time, a ball valve is loosely fitted in the valve chamber, and the ball valve closes the guide hole by writing upward to prevent a reverse flow of ink, with a so-called backflow prevention mechanism. Ballpoint pen refills are known. Although this is highly reliable as a measure to prevent the backflow of ink, conventionally known ones have a problem that the structure is complicated or the number of parts is increased to increase the cost.

A conventional knock-type ballpoint pen has a rotating operation of a barrel, a well-known knocking operation by a Kern-type knocking mechanism, and a knocking operation. A ballpoint pen refill is mounted on the barrel of the writing implement, such as a knock mechanism with a safety mechanism that releases the lock when inserted into the breast pocket and the writing tip enters the shaft, and refills the ballpoint pen with respect to the barrel It is known that the writing tip can be protruded and retracted from the tip of the shaft by changing the axis.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a refill of an oil-based ballpoint pen with a backflow prevention mechanism which can be mounted on a knock-type writing instrument or a normal cap-type writing instrument. The present invention solves the problems of complicated structure and cost increase due to an increase in the number of parts, such as a structure having a joint between ink storage tubes or a structure in which a valve member is fixed in the ink storage tube. .

[0005]

The present invention has the following arrangement to solve the above-mentioned problems. The refill of the ballpoint pen according to the first aspect of the present invention has a tip of the ballpoint pen and an ink storage tube at the rear, and a crimp is formed by plastic deformation on an outer peripheral portion of the ink storage tube at a position appropriately rearward from the rear end of the tip. And at the same time, a partial ridge is formed on the inner periphery, and a ball seat is formed on the inner periphery by plastic deformation on the entire periphery further behind the ridge. This is a ballpoint pen refill that can be mounted on a knock-type writing instrument having a ball valve loosely fitted in a valve chamber formed therebetween and an ink container filled with oil-based ink.

According to a second aspect of the present invention, there is provided a ballpoint pen refill having a tip of a ballpoint pen and an ink storage tube at a rear end thereof, and an outer peripheral portion of the ink storage tube being plastically deformed at a position appropriately rearward from the rear end of the tip. Two recessed deformed portions are formed in the axial direction, a partial ridge is formed on the inner periphery of the front portion, and a ball receiving seat on the entire periphery is formed on the inner periphery of the rear portion. A ball-point pen refill in which a ball valve is loosely fitted into a valve chamber formed and formed between the ridge portion and a ball receiving seat, and an ink container is filled with oil-based ink.

[0007]

1 to 3 show a first embodiment of a ballpoint pen refill according to the present invention. First, the tip 8 of the ballpoint pen and the ink storage tube 2 at the rear are provided at the tip.
A crimp 3 is formed by plastic deformation on the outer peripheral portion of the ink storage tube 2 at a position appropriately rearward from the rear end, and a partial ridge 4 is formed on the inner peripheral portion. As a result, a ball receiving seat 5 is formed on the inner peripheral portion,
A ball valve 13 is loosely fitted in a valve chamber 7 formed between the ridge 4 and the ball receiving seat 5, and the ink container 2 is filled with oil-based ink 14. If necessary, a grease-like follower is provided at the rear end of the ink 14 to follow the ink as the ink is consumed.

[0008] The ink storage tube 2 is an extruded tube made of polypropylene resin or a metal tube. The plastic working of the ink container 2 made of polypropylene resin is performed by heat and pressure using a tool. In addition, a crimp 3 serving as a receiving surface of the rear end of the return spring may be provided separately from the ridge 4.

The tip 8 has a state in which the tip ball 12 is substantially in contact with a seat having a channel 10 into which ink can flow.
The tip ball 12 is swaged so as to be held rotatably. (Ball holding part 9)

FIG. 3 shows a knock-type ballpoint pen on which the refill 1 of the ballpoint pen is mounted. This knock-type ballpoint pen has a ballpoint pen refill 1, a return spring 26 for urging the ballpoint pen rearward, and a knock bar 21 protruding from the rear end of the barrel 20 in conjunction with the ballpoint refill 1. Press the rotor 22
Is rotated so that the projection 23 provided on the front side of the rotor 22 is engaged with and disengaged from the locking step 25 of the clip 24 provided on the side surface of the shaft cylinder, so that the writing tip can protrude and retract from the tip end of the shaft cylinder 20. or,
When the clip 24 is inserted into a breast pocket or the like with the writing tip protruding, the locking between the projection 23 and the locking step 25 is released, and the writing tip is housed in the tip end of the barrel. It is made as follows. Since the configuration of the knock-type ballpoint pen is not the gist of the present application, a detailed description is omitted.

FIGS. 4 to 6 show a ballpoint pen refill according to a second embodiment of the present invention. First, a tip 39 of a ball-point pen and an ink storage tube 31 are provided at the rear end, and two recessed deformed portions 32 in the axial direction are plastically deformed on the outer periphery of the ink storage tube 31 at a position appropriately rearward from the rear end of the tip 39. , 34 are formed, and the deformed portion 32 is partially deformed to form a partial ridge 33 on its inner peripheral portion, and the deformed portion 34 is formed on its inner peripheral portion by deformation on the entire circumference. A ball receiving seat 35 is formed on the entire circumference, and a ball valve 38 is loosely fitted in a valve chamber 36 formed between the ridge portion 33 and the ball receiving seat 35. The ink 44 is filled. If necessary, a grease-like follower is provided at the rear end of the ink so as to follow the ink as the ink is consumed.

As the ink storage tube 31, an extruded tube made of polypropylene resin or a metal tube is used. Ink storage tube 3 made of polypropylene resin
The above-mentioned plastic working is performed by heat and pressure using a tool.

FIG. 7 shows a conventional ballpoint pen refill 50 mounted on a knock-type writing instrument. As shown in the figure, the ball-point refill 50 has a tip 60 fixed to the front end of a joint 51 and an ink storage tube 59 fixed to the rear end. Further, a valve chamber 52 in which a ball valve 58 is loosely fitted is provided at the axial center of the joint 51, and when the chip 60 faces downward, the ball valve 58 abuts on the rear end of the chip in an eccentric state, and ink flows into the chip inner hole. Inflow is allowed. That is, an extra member called the joint 51 is required as compared with the first embodiment. Since the detailed configuration is not directly related to the gist of the present application, the description is omitted. FIG. 8 shows a knock-type writing instrument on which the ballpoint pen refill 50 is mounted.

FIGS. 9 and 10 show a conventional ballpoint pen refill 70 mainly mounted on a cap-type writing instrument or the like. In the refill 70 of the ball-point pen shown in the drawing, a tip 80 is fixed to the tip of an ink storage tube 79, and a valve member 7 is provided in the ink storage tube 79 so as to face the rear end of the shaft portion 81.
1 is fixed. A valve chamber 72 is provided at the axis of the valve member 71, and a ball valve 78 is loosely fitted in the valve chamber.
The ball valve 78 is provided at the front of the valve chamber 72 when the tip 80 faces downward.
The ink is allowed to flow into the inner hole of the chip by contacting the tip. That is, an extra member called the valve member 71 is required as compared with the second embodiment. Since the detailed configuration is not directly related to the gist of the present application, the description is omitted.

[0015]

First, a first embodiment will be described. FIG. 1 shows a state in which the tip 8 is directed upward. At this time, the ball valve 13 is located in the ball receiving seat 5 of the valve chamber 7 and seals the guide hole 6, so that the tip of the tip ball 12 of the tip is written in the upward direction. Even if the ink runs out, the ink is caught by the head and does not flow backward. Further, when the tip 8 of FIG. 2 is turned downward, the ink can flow out. (By the way, in the structure without the ball valve, the ink flows backward by writing upward.)

In a writing state in which the tip 8 is directed downward as shown in FIG. 2, the ball valve 13 comes into contact with the ridge portion 4 and passes from the ink storage tube 2 to the valve chamber 7 through the guide hole 6. The entered ink 14 flows into the chip 8 through the gap formed between the ridges. On the back surface of the tip ball 12, there is a channel 10 (a tip ball receiving seat having a plurality of ink inflow grooves), and an ink guide hole passes through the center of the channel 10. Note that the second embodiment operates in the same manner, and a description thereof is omitted.

[0017]

The structure and operation of the refill of the ballpoint pen according to the present invention are as described above, and the mechanism for preventing the backflow of ink can be easily formed in an automatic assembly machine by plastic deformation of the ink container tube. As a result, it can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an entire refill of a ballpoint pen according to a first embodiment of the present invention, showing a state in which a chip is directed upward.

FIG. 2 is an enlarged cross-sectional view of a main part of a refill of the ballpoint pen according to the first embodiment, showing a state where a chip is directed downward.

FIG. 3 is a longitudinal sectional view of a knock-type writing instrument equipped with the ballpoint pen refill of Example 1.

FIG. 4 is a longitudinal sectional view showing the entire refill of a ballpoint pen which is Embodiment 2 of the present invention, showing a state in which a chip is directed upward.

FIG. 5 is an enlarged cross-sectional view of a forward part of FIG. 4;

FIG. 6 is an enlarged sectional view of a tip portion of a refill of a ballpoint pen according to a second embodiment, showing a state in which a chip is directed downward.

FIG. 7 is a longitudinal sectional view showing the entire refill of a conventional ballpoint pen mounted on a knock-type writing instrument, and shows a state in which a chip is directed upward.

FIG. 8 is a longitudinal sectional view of a conventional knock-type writing instrument equipped with a ballpoint pen refill.

FIG. 9 is an enlarged cross-sectional view of a tip portion of a refill of a conventional ballpoint pen mounted on a cap-type writing instrument or the like;
This shows a state in which the chip is turned upward.

FIG. 10 is an enlarged cross-sectional view of a tip portion of a refill of a conventional ballpoint pen mounted on a cap-type writing instrument or the like, and shows a state in which a chip is directed downward.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ballpoint pen refill 2 Ink accommodating tube 3 Crimp 4 Ridge part 5 Ball receiving seat 5a Deformation part 6 Guide hole 7 Valve room 8 Chip 9 Ball holding part 10 Channel 11 Shaft part 12 Tip ball 13 Ball valve 14 Ink 20 Shaft barrel DESCRIPTION OF SYMBOLS 21 Knock rod 22 Rotor 23 Projection part 24 Clip 25 Locking step part 26 Return spring 30 Refill of ballpoint pen 31 Ink storage tube 32 Deformation part 33 Protrusion part 34 Deformation part 35 Ball receiving seat 36 Valve room 37 Guide hole 38 Ball valve 39 Chip 40 Shaft 41 Inner Hole 42 Channel 42a Receiving Seat 42b Ball Holder 42c Guide Hole 43 Tip Ball 44 Ink 50 Refill of Ballpoint Pen 51 Joint 52 Valve Chamber 53 Groove 54 Guide Hole 55 Flange 56 Shaft 57 Ball Receiver Seat 58 Ball valve 59 Ink storage tube Reference Signs List 60 Chip 61 Shaft 62 Ink 63 Return spring 70 Refill of ballpoint pen 71 Valve member 72 Valve chamber 73 Guide hole 74 Elastic piece 75 Slit split 76 Protrusion 77 Ball receiving seat 78 Ball valve 79 Ink storage tube 80 Tip 81 Shaft

Claims (2)

[Claims] 1. A tip of a ball-point pen and an ink storage tube at the rear thereof are provided at an end thereof. A crimp is formed by plastic deformation on an outer peripheral portion of the ink storage tube at a position appropriately rearward from a rear end of the tip and a partial crimp is formed at an inner peripheral portion. A ball receiving seat is formed on the inner peripheral portion by plastic deformation on the entire periphery further behind the ball, and the ball is formed in the valve chamber formed between the projecting ridge and the ball receiving seat. A ballpoint pen refill that can be mounted on a knock-type writing implement having a valve loosely fitted and an ink-filled tube filled with oil-based ink. 2. A tip of a ball-point pen and an ink storage tube at the rear thereof are provided, and two concave portions are formed on the outer periphery of the ink storage tube by plastic deformation at an appropriate position rearward from the rear end of the tip. At the same time, a partial protruding portion is formed on the inner peripheral portion of the front portion, and a ball receiving seat on the entire circumference is formed on the inner peripheral portion of the rear portion. The ball valve is refilled with a ball valve loosely fitted in a valve chamber formed between the ballpoint pen and the ink container filled with oil-based ink.