JP2539980Y2 - Writing tip - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a writing tip member. More specifically, a writing tip member in which a pen tip is fitted to a front part of a holder and a valve mechanism for controlling ink supply to the pen tip is disposed in a holder behind the pen tip. About.

[Conventional technology]

Conventionally, a spherical valve element is loosely inserted into a writing tip, and when the writing tip is upward, the valve port is closed by the weight of the spherical valve element to prevent backflow of ink.
No. 61, etc., discloses that, when the writing tip is upward, the ink can be prevented from flowing backward, but when the writing tip is downward and receives a strong shock such as dropping, excessive writing may occur in the writing tip. The ink was supplied, and the ink sometimes blew out or bleed out from the writing tip. In addition, when the writing tip is applied to the direct liquid type in which a large amount of ink is stored at the rear part of the barrel, a high head pressure due to the ink is applied to the tip, and ink leakage tends to occur, and the chip itself is likely to be used. With such a small holding force, the head pressure cannot be endured, and as a result, it has been difficult to store a large amount of ink in the rear portion of the barrel.

Further, a writing instrument having a valve mechanism disposed between the main ink chamber and the sub-ink chamber, wherein the valve mechanism is operated by negative pressure in the sub-ink chamber due to ink consumption.
No. -14200 is disclosed. In the writing implement, a valve mechanism is provided between a sub-ink chamber behind the tip via an ink relay core and a main ink chamber at the rear of the barrel. This is because, when the ink is consumed after the start of writing, the negative pressure range is expanded in the chip first, then in the ink relay core, and further in the sub ink chamber, and a predetermined negative pressure is generated in the sub ink chamber. At this time, the valve mechanism operates only for the first time. For this reason,
If the writing is interrupted before a predetermined negative pressure is generated (before the valve mechanism is activated), a slight negative pressure remains in the ink relay core and the sub-ink chamber, and as a result, air is sucked in from the writing tip and the writing is performed. Sometimes it was impossible.

[Problems to be solved by the invention]

The present invention is intended to solve the above-mentioned conventional problems, and to provide a writing tip member capable of holding a large amount of ink at a rear portion of a shaft cylinder at the time of mounting without fear of ink leakage or air suction. is there.

[Means for solving the problem]

The writing tip member 1 of the present invention has a nib 2 fitted to the front of the holder 3 and a valve for controlling ink supply to the nib 2 in the holder 3 behind the nib 2. A writing tip member provided with a mechanism 4 and attached and fixed to a writing instrument main body, wherein the holder 3 has a holding hole 31 at the tip thereof for fitting the pen tip portion 2 therein. At the rear, an ink flow hole 32 smaller in diameter than the holding hole 31 is provided in communication with the holding hole 31, and a valve seat 43 having a reduced diameter is formed at a rear portion of the ink flow hole 32, and the valve seat 43 is formed. An ink introduction hole 33 opened to the rear end of the holder 3 is provided in communication with a central part of the holder 3. A ball 41 is inserted into the ink circulation hole 32, and an elastic body biasing rearward from the front is provided. The ball 41 is pressed against the valve seat 43 by 42a and 42b to close and close the introduction hole 33. State is configured, and the requirements to become is configured to be opened by displacing the ball 41 forward by negative pressure in the ink flow hole 32 with the ink consumption during writing.

The pen tip portion 2 is made of various conventional chips having a writing function, for example, a ball-point pen tip, a fiber tip, a plastic molded tip, a plastic porous tip having continuous pores, which can be written by holding a ball at the tip. And the like.

The holder 3 is integrally formed by injection molding of a synthetic resin.

The hole 41 is formed to have a slightly smaller diameter than the inner diameter of the ink circulation hole 32, and a metal such as stainless steel, a ceramic, a material formed of a synthetic resin or the like is effective.
About 0.5 to 3.0 mm is suitable.

The elastic bodies 42a and 42b can be inserted into the ink circulation holes 32, and have an outer diameter enough to securely hold the front portion of the ball 41,
When ink is consumed, the ball 41 is pressed against the valve seat 43 with a biasing force smaller than the generated negative pressure (suction force on the ball 41). Specifically, a compression coil spring, an elastic body such as rubber or porous urethane, or a fiber bundle having a slight elastic force is used.

[Action]

In the writing tip member 1 of the present invention, when writing, the inside of the ink circulation hole 32 immediately becomes a negative pressure due to the consumption of ink, and when the suction force on the ball 41 becomes larger than the urging force of the elastic bodies 42a and 42b, the ball 41 The elastic members 42a, 42b are drawn forward against the urging force of the elastic members 42a and 42b, and the close contact with the valve seat 43 is released.
The ink is led into the flow holes 32.

When the negative pressure is weakened by the ink introduction and the suction force on the ball 41 becomes smaller than the urging force of the elastic bodies 42a and 42b, the ball 41 is again pressed against the valve seat 43, the valve mechanism 4 is closed, and the ink introduction is stopped. I do.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a first embodiment. The pen tip 2 is a ball-point pen tip holding a ball 41 at the tip. The tip of the pen tip 2 is fitted into the holding hole 31 at the tip of the holder 3, and the trailing end is in contact with the locking step 31a. The holder 3 is obtained by injection molding of a synthetic resin.
3), and an ink introduction hole 33 is provided at the rear end. The valve seat 43 has a tapered surface facing the ink introduction hole 33, and the ink introduction hole 33 is provided at the center thereof in the rear end direction, and is formed integrally with the holder 3.

In the ink flow hole 32, a coil spring 42 is provided.
a is contained and it is a stainless steel ball 41
Is pressed backward against the valve seat 43. The coil spring 42a has a rear end face of the pen tip portion 2 as a seat and is held in a slightly compressed state.

FIG. 2 shows a second embodiment. In this case, an ink guide core 34 is inserted into the ink circulation hole 32 of the first embodiment. The ink guide core 34 is formed of a fiber bundle, is inserted inside the coil spring 42a, and has a rear end extending to near the front surface of the ball 41. By the capillary force of the ink guide core 34, smooth supply and holding of the ink are enabled.

FIG. 3 shows a third embodiment. A resin processed body of a fiber bundle is adopted for the pen tip portion 2, and other members are the same as those in the first and second embodiments. The pen tip portion 2 is subjected to a grinding process rearward, and a shoulder portion 22 and a small diameter portion 23 are formed. When the pen tip portion 2 is fitted to the holder 3, the shoulder portion 22 abuts on the locking step 31 a of the holder 3 and is positioned to prevent the pen tip portion 2 from moving backward. Also, the shoulder
22 also functions as a seat for the coil spring 42a.
The small diameter portion 23 is inserted inside the coil spring 42a in the ink flow hole 32, and its rear end reaches near the front surface of the ball 41.

FIG. 4 shows a fourth embodiment. A resin processed body of a fiber bundle is attached as the pen tip portion 2, and a sponge 42b is attached as an elastic body. The rear end of the pen tip 2 is inserted up to the rear of the holder 3 to form a small ink flow hole 32 between the rear end surface and the ball 41.
42b is slightly compressed.

In the first to fourth embodiments (FIGS. 1 to 4), the ball 41 was set to an outer diameter of 1.3 mm, the ink circulation hole 32 was set to an inner diameter of 1.5 mm, and the ink introduction hole 33 was set to an inner diameter of 0.5 mm. Further, the negative pressure in the ink circulation hole 32 during writing depends on conditions such as the type of chip and the writing speed, but when actually measured, it is approximately
50~300mmH was ₂ O. Therefore, the urging force of the elastic bodies 42a and 42b on the ball 41 is set smaller than the suction force due to the negative pressure.

FIG. 5 shows an example of application of a writing implement provided with the writing tip member 1 of the present invention.
This is a writing implement of the type in which the ink cylinder 52 is mounted and the rear part of the barrel 5 is formed as an ink reservoir 51. The ink adjusting member 52 has the tip of the second embodiment (see FIG. 2) assembled thereto.

FIG. 6 shows an application example of the writing instrument cartridge, in which the first embodiment (see FIG. 1) is mounted at the tip of the cartridge 6. Impregnating body 61 at the rear of cartridge 6
Then, the ink is guided to the ink introduction hole 33 at the rear end of the writing tip member 1 by the relay core 63 connected to the front part of the impregnation body 61.

FIG. 7 shows a writing instrument of a type having a slide stopper 54 slidable in the ink storage section 51 at the rear portion of the barrel 5, the tip of which is mounted with the third embodiment (see FIG. 3). .

[Effect of the invention]

According to the present invention, as described above, when the writing tip is upward, not only the ink in the ink circulation hole is prevented from flowing backward, but also when the writing tip is downward, a strong impact such as dropping is applied, or a large capacity. Even if the head pressure at the tip end of the chip is increased by containing the ink, no ink leakage occurs due to the buffering action of the valve mechanism.

Also, according to the present invention, the pressure inside the ink flow hole becomes negative pressure due to the outflow of ink from the writing tip almost at the same time as the start of writing, and the valve mechanism operates immediately and sensitively according to the negative pressure to introduce the ink. Is eliminated, the negative pressure state hardly remains in the circulation holes, and therefore, air is prevented from entering the ink circulation holes.

In addition, although the valve mechanism is small in size, the structure is relatively simple, which is advantageous not only in manufacturing but also because the valve mechanism is housed in the writing tip member, so that the writing instrument main body side to be mounted is mounted. Can be easily put into practical use without requiring any change to the conventional one.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing a second embodiment of the present invention, and FIG. 3 is a longitudinal sectional view showing a third embodiment of the present invention. FIG. 4 is a longitudinal sectional view showing a fourth embodiment of the present invention, FIG. 5 is an application example of the second embodiment, and FIG.
FIG. 7 is a longitudinal sectional view showing an application example of the first embodiment, and FIG. 7 is a longitudinal sectional view showing an application example of the third embodiment. DESCRIPTION OF SYMBOLS 1 ... Writing tip member 2 ... Pen tip 21 ... Tip ball 22 ... Shoulder 23 ... Small diameter part 3 ... Holder 31 ... Holding hole 32 ... Ink circulation hole 33 ... Ink introduction hole 34 ... … Ink guide core 4 …… Valve mechanism 41 …… Ball 42a …… Coil spring 42b …… Sponge 43 …… Valve seat 43a …… Tapered surface 5 …… Shaft cylinder 51 …… Ink reservoir 52 …… Ink adjusting member 53 ... Relay core 54 ... Slide stopper 6 ... Cartridge 61 ... Impregnated body 62 ... Tail plug 63 ... Relay core

Claims (1)

(57) [Scope of request for utility model registration] 1. A pen tip (2) is fitted to a front part of a holder (3), and the pen tip (2) is inserted into a holder (3) behind the pen tip (2). A writing tip provided with a valve mechanism (4) for controlling the ink supply of the writing instrument, the pen tip (2) being fitted to the tip of the holder (3). A holding hole (31) is provided, and an ink circulation hole (32) having a smaller diameter than the holding hole (31) is provided behind the holding hole (31) in communication with the holding hole (31). Ink circulation holes (32)
A valve seat (43) is formed at a rear portion of the valve seat (43) with a reduced diameter, and an ink introduction hole (33) opening to the rear end of the holder (3) is provided in communication with a center portion of the valve seat (43). A ball (41) is inserted into the ink flow hole (32), and the ball (41) is attached to the valve seat (43) by an elastic body (42a, 42b) that urges rearward from front. The ball (41) is displaced forward by the negative pressure in the ink flow hole (32) due to ink consumption during writing, and the ball (41) is opened by being pressed and closing the inlet hole (33). A writing tip member (1) configured to be valveable.