JPH0623788U - Ball pen refill - Google Patents

Abstract

(57) [Summary] [Structure] The small-diameter portion 3 is a connection portion that is press-fitted into the inner wall of the pipe body C. In this small diameter portion 3, from the position of the step portion 4 formed as a boundary between the large diameter portion 2 and the small diameter portion 3, the pipe body C
A circumferential protrusion 5 is formed at a distance of one third of the inner diameter. When the tip holder-D is connected to the pipe body C, the circumferential projection 5 serves as a strong press-fitting portion in line contact with the inner wall of the pipe body C. [Effect] The sealing property of the connection portion between the inner wall of the pipe and the tip holder-outer wall is improved, and the phenomenon that ink leaks or ink evaporates and the ink contained in the pipe gradually decreases is suppressed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 A ball-point pen refill used for ball-point pens that keeps the pen tip airtight by bringing a non-ink permeable elastic body installed inside the cap into contact with the pen tip by attaching a cap. Is a synthetic resin extruded product containing ink of 50 centipoise or more, a metal ball-pen tip, and the pipe body and the ball-pen tip are connected to each other, and the pipe body and the ball-pen tip are connected by ink. And a ball pen tip holder, which relates to a ball pen refill in which a small diameter portion is press-fitted and fixed to an inner wall of a pipe body.

[0002]

[Prior art]

 Conventionally, as a low-priced ballpoint pen mainly used for office work, the ink is built in freely in the pipe body, which is an extruded product of synthetic resin such as polypropylene and polyethylene, without using an ink holding member such as batting. However, there is known a ball-pen refill in which a metallic ball-pen tip such as stainless steel or nickel silver is press-fitted directly into this pipe body.

When the size of the ball pen tip and the inner diameter of the pipe do not match, a ball pen tip holder made of synthetic resin such as polypropylene, polyoxymethylene, polybutylene terephthalate, etc. is interposed between the two. In some cases, the ink inside the pipe is connected to the ball-point tip. In particular, when an ink with a low viscosity such as 50 centipoise to 5000 centipoise, such as a water-based ink, is used, the amount of ink discharged during writing is large, so the amount of ink incorporated in the pipe body is also large. There is a need to. Therefore, since a pipe having a large inner diameter is often used, and there is a difference between the outer diameter of the connecting portion of the tip and the inner diameter of the pipe body, the ball pen tip holder is used.

[0004]

[Problems to be Solved by the Invention] Innumerable streaks of about 0.02 to 0.1 mm are formed on the inner wall of a pipe body by extrusion molding of synthetic resin. In the ball-pen refill using the above-mentioned ball-pen tip holder, a gap is formed at the connection part between the inner wall of the pipe and the outer wall of the tip holder, and ink leaks or ink evaporates and the pipe body There was a problem that the amount of ink contained in the pipe gradually decreased, and the amount of ink in the pipe decreased considerably from the time of manufacture to the time of use, and the amount of ink within a period of time after use was maintained. . In particular, when using a ball-point pen that keeps the pen tip airtight by contacting the pen tip with a non-ink permeable elastic body such as sillcongo installed in the cap by capping, Even if it is unused, the amount of ink will continue to decrease, and there is a possibility that the reliability of products and manufacturers will be greatly impaired.

[0005]

[Means for Solving the Problems]

 The present invention is a ball-pen refill used for a ball-point pen in which a non-ink permeable elastic body installed in the cap by contacting the pen tip is kept airtight by capping the cap. , A pipe body, which is an extruded product of a synthetic resin containing an ink with a viscosity of 50 centipoise or more, a metal ball-pen tip, and the pipe body and the ball-pen tip are connected to form a pipe body and a ball-pen tip. And a ball pen tip holder for ink-connecting the ball pen tip holder, wherein the ball pen tip holder is a ball pen refill in which a small diameter portion is press-fitted and fixed to an inner wall of a pipe body. A ball pen refill is characterized in that a protrusion is formed on the entire circumference, and a strong press-fitting portion having a linear shape is formed on the connection portion with the pipe body.

[0006]

【Example】

 Hereinafter, description will be given with reference to the drawings. FIG. 1 shows a ball pen refill A of the present invention, reference numeral B is a stainless steel ball pen tip, reference numeral C is a polypropylene pipe body, reference numeral D is a polybutylene terephthalate tip. It is a holder. The rear portion of the ball-pen tip A is a portion having a reduced diameter as a connection portion with the tip holder-D, and the outer wall of this portion is press-fitted into the inner wall of the tip holder-D. The rear portion of the tip holder-D has a reduced diameter as a connecting portion with the pipe body C and is press-fitted into the inner wall of the pipe. The pipe body C has a viscosity of about 180 centipoise (hereinafter, cp) inside (viscosity measurement condition: at room temperature 25 ° C. at the time of measurement, less than 50 cp, measured by Tokimec ELD viscometer 10 rpm, 50 cp or more 600 cp) Less than is measured by Tokimec ELD viscometer 1 rpm, 600 cp or more and less than 5500 cp is measured by Tokimec ELD viscometer ST type rotor-20 rpm, 5500 cp or more is Tokimec ELD Type viscometer ST type rotor (measured at 10 rpm)) water-based pigment ink and ink backflow preventer composition which is a gel of liquid polybutene so that it is located at the rear end portion of the ink. There is.

FIG. 2 shows a half sectional view of the tip holder-D. The outer wall 1 is composed of a large-diameter portion 2 and a small-diameter portion 3, and the large-diameter portion 3 has a taper shape so that the outer shape of the pipe body C is smoothly connected to the outer shape of the ball pen tip B. The small diameter portion 3 is a connecting portion that is press-fitted into the inner wall of the pipe body C. The small-diameter portion 3 has a stepped portion 4 formed as a boundary between the large-diameter portion 2 and the small-diameter portion 3 (the open end of the pipe body C comes into contact with the pipe body C when the pipe body C is connected) to the inner diameter of the pipe body C. A circumferential projection 5 is formed at a distance of 1/3 of the above. The closer the position of the projection 5 is to the opening end of the pipe body C, the more the reliability of the hermeticity becomes low, and the cracks at the opening portion of the pipe body C are caused. When this tip holder-D is connected to the pipe body C, the circumferential projection 5 becomes a strong press-fitting portion in line contact with the inner wall of the pipe body C.

FIG. 3 shows an enlarged view of the I portion of FIG. The protrusion 5 formed on the small diameter portion 3 of the tip holder-D has a triangular cross section so that when it comes into contact with the inner wall of the pipe, it makes point contact. Here, since the outer diameter of the small-diameter portion 3 is set to be slightly larger than the inner diameter of the pipe body C, the press-fitted state is further strengthened at the protruding portion 5, and the inner wall of the pipe body C is bitten and sealed. is doing. The protrusion 5 is set so that the inclination angle θ1 on the pen tip side and the inclination angle θ2 on the rear end side are θ1 ≧ θ2, so that the protrusion 5 is easily inserted at the time of installation and is hard to be removed.

FIG. 4 shows another embodiment. Since the ball-pen tip B and the pipe body C are the same as those in the previous embodiment, only a half sectional view of the tip holder-D 'is shown. The present embodiment differs from the previous embodiments in that a circumferential projection 6 is provided at the rear end portion of the small diameter portion 3'from the projection 5 '. As shown in the enlarged view II of FIG. 4 shown in FIG. 5, the protrusion 6 has a larger inclination angle θ4 on the rear end side than the inclination angle θ3 on the pen tip side, and the inclined portion 7 forming θ4 is It continues to the rear end 8 of the tip holder-D 'at the same angle, and the rear end of the tip holder-D' has a reduced diameter. When the tip holder-D 'of this embodiment is press-fitted into the pipe body C, the protrusions 6 are moved in a strong press-fit state while contacting the inner wall of the pipe body. Since the protrusion 6 crushes the streak peculiar to extrusion molding formed on the inner wall of the pipe body C, the streak at the connecting portion is shallow at the time of complete connection. Therefore, the sealing property can be further improved at the contact portion between the projection 5'and the inner wall of the pipe body. Further, since the projection 6 also has the hermeticity, the hermeticity as a whole is further improved, and the chip holder-D 'is also fixed securely.

[0010]

[Effect of device]

 The ball-pen refill of the present invention is used for a ball-point pen in which a non-ink permeable elastic body installed in the cap is brought into contact with the pen tip by holding the cap, and the pen tip is kept airtight. -A pipe body which is a repen refill and is an extruded product of a synthetic resin containing an ink having a viscosity of 50 centipoise or more, a metal ball-pen tip, and the pipe body and the ball-pen tip connected to each other. A ball-point pen tip holder comprising a ball-point pen tip holder for ink-connecting a pipe body and a ball-point pen tip, and the ball-point pen tip holder is a ball-point pen refill in which a small diameter portion is press-fitted and fixed to the inner wall of the pipe body. Since the projection of the entire circumference is formed on the outer wall of the small-diameter portion of the ball-pen tip and the strong press-fitting portion of the entire circumference is formed at the connecting portion with the pipe body, the inner wall of the pipe and the tip holder- It improves the airtightness of the connection part with the wall, and suppresses the phenomenon that ink leaks and the ink that evaporates and the amount of ink contained in the pipe gradually decreases, which improves the reliability of the product and the manufacturer. To keep.

[Brief description of drawings]

FIG. 1 is a half sectional view of a main part showing an embodiment.

FIG. 2 is an enlarged view of one part of the embodiment.

FIG. 3 is an enlarged view of a main part of FIG.

FIG. 4 is an enlarged view of a part of another embodiment.

5 is an enlarged view of a main part of FIG.

[Explanation of symbols]

 A ball pen refill B ball pen tip C pipe body D tip holder-D 'tip holder-1 outer wall 2 large diameter portion 3 small diameter portion 4 step portion 5 protrusion θ1 inclination angle θ2 inclination angle 3'small diameter portion 5'projection portion 6 Projection θ3 Inclination angle θ4 Inclination angle 7 Inclination part 8 Rear end

Claims (1)

[Scope of utility model registration request] 1. A non-ink permeable elastic body placed inside the cap by contacting the pen tip,
Ball used for a ball-point pen whose airtight nib is held
A pipe body which is a lupen refill and is an extruded product of a synthetic resin containing an ink having a viscosity of 50 centipoise or more, a metal ball-pen tip, and a pipe body which is connected to the pipe body and the ball-pen tip. A ball-pen tip holder for ink-connecting a ball-pen tip with a ball-pen tip holder, wherein the ball-pen tip holder is a ball-pen refill in which a small-diameter portion is press-fitted and fixed to an inner wall of a pipe body. A ball pen refill characterized in that an outer peripheral projection is formed on an outer wall of the small diameter portion, and a strong press-fitting portion having a linear shape is formed on a connecting portion with the pipe body.