JP2683511B2 - Writing implement - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a felt tip pen,
The present invention relates to various markers such as a whiteboard marker and other writing instruments. More specifically, the present invention relates to a writing instrument having a mechanism for supplying a predetermined amount of ink for each writing.

[0002]

2. Description of the Related Art Conventionally, in a writing instrument such as a felt tip pen, a porous material such as batting is filled in the ink chamber of the pen shaft, and the ink is held in the batting by a capillary force. However, in such a case, since the amount of ink that can be held is small and the flow rate of the ink that can be supplied from the batting to the felt tip and the like is extremely small, there is a problem that the handwriting is faint when writing quickly. Further, in the case of such a structure, the ink cannot be supplied to the pen body unless the capillary force of the pen body sucking the ink is larger than that of the batting. Therefore,
As the pen body, there is a problem that only a felt tip or the like having a large capillary force can be used.

In order to solve such a problem, liquid ink is directly stored in a cylindrical ink storage chamber, and a slidable slide plug for partitioning ink and air is inserted into the ink storage chamber. A so-called direct liquid type writing instrument has been developed in which the slide stopper slides in response to ink consumption. Since such a direct liquid type writing instrument can store a large amount of ink, and the flow rate of ink supplied to the pen body is not basically limited, and the ink suction capacity of the pen body is not limited. Water-based ball tip as a pen,
There is an advantage that various other pen bodies can be used.

However, such a writing instrument requires a mechanism for supplying to the pen body an amount of the liquid ink contained in the ink storage chamber in an amount corresponding to the amount consumed in writing.
Such an ink supply control mechanism must supply a small amount of ink to the pen body in accordance with the amount of ink consumed by writing. In addition, if the temperature and atmospheric pressure change, it is necessary to prevent the ink in the ink storage chamber from being excessively pushed out and falling from the pen body, and conversely, the air from being sucked into the IN storage chamber. I won't.
Such an ink supply control mechanism is roughly classified into a differential pressure type and a pump type.

The above differential pressure type ink supply control mechanism is
A valve mechanism is provided between the pen body and the ink storage chamber to open when a predetermined pressure difference occurs. Then, when the ink is consumed by writing, the pen body sucks the ink by its capillary force, and a differential pressure is generated between the pen body and the ink storage chamber, and this differential pressure becomes equal to or higher than a predetermined differential pressure. In this case, the valve mechanism is opened, and an appropriate amount of ink is supplied from the ink storage chamber side to the pen body side. In addition, when writing is not performed, the valve mechanism is closed, the communication between the ink storage chamber and the pen body is cut off, and the ink in the ink storage chamber expands and contracts to cause the ink to flow into the pen. It prevents fluttering from the body and sucking air into the ink storage chamber through the pen. The expansion and contraction of the ink is compensated by the sliding of the slide plug.

As a pen body of a writing instrument having such a differential pressure type ink supply control mechanism, at least the valve mechanism of the above ink supply control mechanism is opened and the sliding resistance of the above slide stopper is overcome. It must have sufficient ink suction pressure to slide the slide plug. Therefore, in practice, the ink suction pressure may be insufficient with a water-based ball tip or the like, and in order to obtain stable characteristics with such a writing instrument, only a felt tip with a high ink suction pressure can be used as a pen body. There was a problem.

For whiteboard markers and the like, quick-drying alcohol-based ink is used. Further, recently, quick-drying alcohol-based inks have been developed for writing instruments for writing on paper. Such an alcohol-based ink has a weak capillary force, and in some cases, a sufficient ink suction pressure cannot be obtained even if the above felt tip is used.

Further, the pump type ink supply control mechanism is
A pen body is provided slidably with respect to the pen shaft, and a pump mechanism for supplying a predetermined amount of ink in the ink storage chamber to the pen body by sliding the pen body is provided in the pen shaft. . In such a case, when writing pressure acts on the pen body by writing, the pen body moves and ink is pushed out to the pen body by the pump mechanism.

Such a pump type is simple in operation and does not require the capillary force of the pen body to supply the ink, so that there is no limitation on the type of the pen body or the ink. . However, the amount of ink consumed by one stroke of writing is extremely small, and it has been difficult to design the pump mechanism so as to accurately supply such a small amount of ink.

That is, since the pump mechanism as described above operates by moving the pen body by the writing pressure, the amount of ink pushed out differs depending on the strength of the writing pressure. On the other hand, there are writers who write small characters with strong writing pressure and writers who write large characters with weak writing pressure. In such a case, in the former case, more ink than the amount consumed by writing is supplied to the pen body, and when writing is continued, excessive ink is supplied to this pen body, causing problems such as ink dripping. Further, in the latter case, the amount of ink pushed out by the pump mechanism becomes smaller than the amount of ink consumed by writing, and when writing continues, the amount of ink supplied to the pen body becomes insufficient, causing problems such as blurred handwriting. Sometimes.

Further, since all of the above ink supply control mechanisms are built in the pen shaft, they must be formed in a small size, and disposable writing instruments must be manufactured at low cost. I have to. Therefore, it is difficult for this ink supply control mechanism to develop a mechanism that satisfies the above requirements in all aspects.

[0012]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances, and in a so-called direct liquid type writing instrument that directly contains liquid ink, an amount corresponding to the amount of ink consumed in writing. Ink can be accurately supplied to the pen body, the structure is simple and the manufacturing cost is low, and the operation is reliable and it is possible to reliably prevent ink from dripping or sucking air into the ink storage chamber. (EN) It is possible to provide a writing instrument that can be made and is not restricted by the type of pen or ink.

[0013]

The writing instrument of the present invention comprises a pen shaft, an ink storage chamber formed in the pen shaft for directly containing liquid ink, and a liquid-tight slidable member in the ink storage chamber. A slide stopper that partitions the ink and the air and slides in response to the consumption of the ink, and partitions the ink storage chamber and the tip end of the pen shaft that are installed in the pen shaft. And a diaphragm member made of an elastic material that elastically deforms toward the ink storage chamber side to reduce the internal volume of the ink storage chamber, and the tip end of the pen shaft is movably provided in the axial direction of the pen shaft. The pen body is attached to the holder, the rear end of the pen body is connected to the center of the diaphragm member, and a communication passage for supplying ink from the ink storage chamber to the pen body is formed inside. A notch-shaped opening that is formed in the center of the diaphragm member and that is opened when the diaphragm member is elastically deformed toward the ink storage chamber side to communicate the ink storage chamber with the communication passage. It is a thing.

[0014]

In the above-mentioned writing instrument of the present invention, when the writing pressure is applied to the pen body, the pen body retracts together with the holder to elastically move the diaphragm member to the ink reservoir chamber side. It deforms to reduce the internal volume of the ink storage chamber and pressurizes the ink in the ink storage chamber.
Along with this, the notch-shaped opening is opened by elastic deformation of the diaphragm member so that the ink reservoir chamber and the communication passage are communicated with each other. Therefore, the ink in the pressurized ink storage chamber is supplied to the pen body through the opening and the communication passage in the holder. In this case, when the pressure in the ink storage chamber rises due to the deformation of the diaphragm member, the slide plug slides. Therefore, the amount of increase in the pressure in the ink storage chamber in this case is a pressure corresponding to the sliding resistance of the slide stopper, and the pressure in the ink storage chamber increases more than the pressure corresponding to the sliding resistance of the slide stopper. There is nothing to do. Therefore, whether the writing pressure is strong or weak, the amount of increase in the pressure in the ink storage chamber is limited to a predetermined pressure corresponding to the sliding resistance of the slide plug. Therefore, regardless of the writing pressure, a constant amount of ink is always stably supplied to the pen body, and stable writing is possible.

According to a preferred embodiment of the present invention,
The opening is opened after the diaphragm is deformed and the slide plug starts sliding. Therefore,
The slide stopper starts sliding and its sliding resistance becomes dynamic friction resistance, the sliding resistance stabilizes, and the pressure in the ink storage chamber stabilizes before opening. Therefore, the pressure when the ink is supplied to the pen body becomes a predetermined stable pressure, and the amount of the ink supplied to the pen body is more accurate and stable.

Further, in this writing instrument, when writing pressure is not applied to the pen body, that is, when writing is not performed, the opening of the diaphragm member is completely closed, and the ink storage chamber side and the pen Communication with the body side is cut off. Therefore, even if the atmospheric pressure changes or the temperature changes, the ink in the ink storage chamber is pushed out and drops from the pen body, or the air is sucked in from the pen body side. There is no.

Further, this writing instrument has no restriction on the capillary force of the pen body or the type of ink, and various types of pen bodies and ink can be used. Further, it has a simple structure, can be easily manufactured at low cost, and is suitable for a disposable writing instrument.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 3 show a reference example of the present invention. This reference example is a whiteboard marker using an alcohol-based quick-drying ink.

FIG. 1 is a vertical sectional view of the entire whiteboard marker. Reference numeral 1 in the drawing is a pen shaft, and the inside of the pen shaft 1 is formed into a cylindrical ink storage chamber 2, and the ink storage chamber 1 is filled with liquid ink. Further, an ink supply control mechanism 3 is provided on the tip end side of the pen shaft 1 and supplies an appropriate amount of ink to the pen body, in this embodiment, the felt tip 4. In addition, 5 is a cap.

A slide stopper 6 is slidably inserted in a liquid-tight manner at the rear end of the ink storage chamber 2 in the pen shaft 1, and the slide stopper 6 is set in advance. It is designed to slide with a predetermined sliding resistance. Further, a tail plug 7 is attached to the rear end portion of the pen shaft 1, and an atmosphere communication hole 8 is formed in the tail plug 7, and the inside of the pen shaft 1 and the atmosphere are connected via the atmosphere communication hole 8. Are in communication.

The slide plug 6 is made of an elastic material such as silicone rubber and has a cylindrical shape. A seal portion 9 is formed on the peripheral portion of the slide plug 6, and the seal portion 9 is in sliding contact with the inner peripheral surface of the ink storage chamber 2 to maintain liquid tightness. Therefore, as the ink in the ink storage chamber 2 is consumed, the slide plug 6 slides toward the tip side to compensate for the consumption of the ink, and the pressure in the ink storage chamber 2 is approximately atmospheric pressure. Maintain equal pressure.
In addition, a small amount of a lubricant such as ethylene glycol is filled in the pen shaft 1 between the slide plug 6 and the tail plug 7 to ensure the sealing property and to smoothly slide the slide plug 6. To do. By filling with such a lubricant, when the slide stopper 6 is retracted, the lubricant is interposed between the seal surface of the slide stopper 6 and the inner peripheral surface of the ink storage chamber 2 to cause the slide. In addition to reducing the resistance when the stopper 6 moves forward, ink traces do not remain on the inner peripheral surface of the ink storage chamber 2.

Next, the structure of the ink supply control mechanism 3 will be described with reference to FIGS. 2 and 3. That is, the slide guide portion 11 is formed at the tip of the pen shaft 1. A slide holder 12 is slidably guided in the slide guide portion 11 in the axial direction. The felt tip 4 is attached to the tip of the slide holder 12.

A diaphragm member 13 is attached to the base end of the slide guide 11. The diaphragm member 13 is made of an elastic material such as silicone rubber and has a disk shape. The outer peripheral surface of the diaphragm member 13 is in close contact with the inner peripheral surface of the base end portion of the slide guide portion 11 to maintain liquid tightness. Therefore, the diaphragm member 13 separates the ink storage chamber 2 side from the pen body 2 side.

A circular opening 14 is formed in the center of the diaphragm member 13. A fitting protrusion 15 is provided at the center of the base end of the slide holder 12. The fitting protrusion 15 has a cylindrical shape with a circular cross section. Then, the fitting convex portion 15
Is elastically fitted in the opening 14 of the diaphragm member 13, and the inner peripheral surface of the opening 14 of the diaphragm member 13 is in close contact with the outer peripheral surface of the fitting convex portion 15.

Further, in the central portion of the fitting convex portion 15 described above,
An axial passage 17 is formed, and a radial opening 16 is formed at the tip of the passage 17, and the opening 16 is open at a predetermined position on the outer peripheral surface of the fitting projection 15.
The passage 17 communicates with the felt tip 4 via a communication passage 18.

When the writing pressure is not applied to the felt tip 4, that is, when the writing is not performed, FIG.
As described above, the diaphragm member 13 is not elastically deformed, and the inner peripheral surface of the opening 14 of the diaphragm member 13 is in close contact with the outer peripheral surface of the fitting convex portion 15 of the slide holder 12, and the outer peripheral surface The opening 16 is closed. Therefore, in this state, the communication between the inside of the ink storage chamber 2 and the felt tip 4 is cut off.

When writing with the whiteboard marker, as shown in FIG. 3, the felt tip 4 is pressed against the whiteboard 21 and a writing pressure is applied. Then, due to this writing pressure, the slide holder 12 is retracted, and the diaphragm member 13 is elastically deformed toward the ink storage chamber 2 side as shown in FIG. Due to the elastic deformation of the diaphragm member 13, the volume on the ink storage chamber 2 side decreases and the pressure in the ink storage chamber 2 rises. The increase in the pressure in the ink storage chamber 2 in this case corresponds to the sliding resistance when the slide plug 6 retracts. At the same time, the diaphragm member 13 elastically deforms toward the ink storage chamber 2 in a substantially conical shape, so that the opening 14 at the center of the diaphragm member 13 also deforms into a conical shape, as shown in FIG. The inner peripheral surface of the opening 14 is separated from the outer peripheral surface of the fitting protrusion 15 of the slide holder 12. Therefore, the opening 16 on the outer peripheral surface of the fitting convex portion 15 is opened. Therefore, the ink storage chamber 2 and the felt tip 4 are communicated with each other through the opening 16, the passage 17, and the communication passage 18. Therefore, the ink in the ink storage chamber 2 is supplied to the felt tip 4 through these passages.

In this reference example, the opening 14 at the center of the diaphragm member 13 is deformed and the fitting projection 15 is formed.
The timing at which the opening 16 on the outer peripheral surface is opened is set so as to be opened after the start of elastic deformation of the diaphragm member 13. This diaphragm member 13
The timing at which the elastic deformation starts and the opening of the opening 16 can be arbitrarily set by the shapes of the diaphragm member 13 and the fitting convex portion 15. For example, this timing can be set by the initial radial compression amount of the diaphragm member 13 that occurs when the diaphragm member 13 is press-fitted into the pen shaft 1, and the initial radial compression amount of the diaphragm member 13 is Larger, opening 1
The timing of opening 6 is delayed. Also, this opening 16
This timing can be set also by the axial position of, and the closer the position of this opening 16 is to the front side,
The opening timing of the opening 16 is delayed.

Next, the operation of the writing instrument of this reference example will be described with reference to FIGS. 4 to 9. FIG. 4 shows a state in which no writing is done. In this case, the diaphragm member 13 is not deformed, and the opening 14 is in close contact with the outer peripheral surface of the fitting convex portion 15 of the slide holder 12, and the opening 16 is closed. Therefore, in this case, the communication between the ink storage chamber 2 and the felt tip 4 is completely cut off. Therefore, even if the ink in the ink storage chamber 2 expands and contracts due to changes in temperature, atmospheric pressure, etc., the ink drops from the felt tip 4 and the inside of the ink storage chamber 2 passes through the felt tip 4. It is completely prevented that the ink is sucked in. In this case, the expansion and contraction of the ink is compensated by the sliding of the slide plug 6.

Next, FIG. 5 shows a state in which writing is started with this writing tool. When the felt tip 4 of this writing instrument is pressed against the whiteboard, the slide holder 12 retracts due to the writing pressure, and the diaphragm member 13 starts elastic deformation. However, in this state, the opening 16 is not yet opened as described above. In this case, due to the elastic deformation of the diaphragm member 13, the ink in the ink storage chamber 2 is compressed and the pressure rises. Then, the slide plug 6 starts sliding due to this pressure. In the stationary state, the outer peripheral surface of the seal portion 9 of the slide stopper 6 is in close contact with the inner peripheral surface of the ink storage chamber 2, and the lubricant film and the ink film are interposed between these seal surfaces. Not not. Therefore, the initial sliding resistance of the slide plug 6 is considerably large. Further, the initial sliding resistance varies considerably depending on the manufacturing error and the contact state between the seal portion 9 of the slide stopper 6 and the inner surface of the ink storage chamber 2.

However, as described above, when the pressure in the ink storage chamber 2 rises, the ink penetrates into a part between these seal surfaces to form an ink film, and further the pressure causes the slide stopper 6 to slide. When the slides start sliding, a film of ink and lubricant is formed entirely between these sealing surfaces. In this state, the sliding resistance of the slide plug 6 is reduced,
In addition, the sliding resistance in this state has a stable and constant value. The state of FIG. 5 is an initial short-time state in which the felt chip 4 contacts a whiteboard or the like.

Next, when the writing pressure is further increased, as shown in FIG. 6, the diaphragm member 13 is further elastically deformed, the opening 16 is opened, and the inside of the ink storage chamber 2 and the felt tip 4 communicate with each other. In this case, the slide plug 6 is already in a sliding state, the sliding resistance is stable, and thus the pressure in the ink storage chamber 2 is a stable predetermined pressure. Therefore, from the inside of the ink storage chamber 2, a predetermined and accurate amount of ink is fed to the felt tip 4
Supplied to

In this state, the writing for one stroke is completed, and the felt tip 4 starts to separate from the surface of the whiteboard. In this case, first, as shown in FIG.
The diaphragm member 13 starts to return due to elasticity in a state where the ink storage chamber 2 is opened, and the volume in the ink storage chamber 2 starts to increase. As a result, the pressure in the ink storage chamber 2 begins to drop and the slide plug 6 stops. Then, the inside of the ink storage chamber 2 has a negative pressure, and the slide plug 6 starts to move forward by this negative pressure. In this case, this ink storage chamber 2
The ink contained in the felt tip 4 is sucked back into the ink storage chamber 2 through the opening 16 by the negative pressure generated therein. However, when the amount of ink contained in the felt tip 4 decreases, the ink suction force (capillary force) of the felt tip 4 increases and the resistance at the time of sucking back the ink increases. The ink in the felt tip 4 is sucked back to some extent.

Such ink sucking back action is not a problem for this writing instrument, and in the case of the whiteboard marker as in this reference example, it is possible to suck back the excess ink and stabilize the writing characteristics. You can That is, in the case of the whiteboard marker, the surface of the whiteboard to be written does not have water absorption and has no ability to adsorb ink. Therefore, in the case of such a whiteboard marker, a thicker and clearer handwriting can be obtained by setting the amount of ink supplied to the felt tip 4 to a large amount within a range where defects such as dripping do not occur. However, in this case, the amount of ink contained in the felt tip 4 gradually becomes excessive as the writing is continued, and if the writing is continued for a long time, ink dripping or the like may occur. is there. However, as described above, if the excess ink contained in the felt tip 4 is sucked back every time the writing for one stroke is completed, even if the writing is continued continuously, fluffing or the like may occur. Not likely to happen.

Next, as shown in FIG. 8, when the diaphragm member 13 is further returned, the slide stopper 6 is further advanced, the opening 16 is closed, and the sucking of the ink is completely stopped.

When the felt tip 4 is separated from the white board, the diaphragm member 13 is completely returned, the slide stopper 6 is stopped, and the inside of the ink storage chamber 2 is at atmospheric pressure, as shown in FIG. Return to the state shown in.

FIG. 10 shows an example of setting the elastic deformation stroke of the diaphragm member 13 and the opening timing of the opening 16 in the case of the whiteboard marker of this reference example. This one has a writing pressure of 70g and a stroke of 0.9m.
The opening 16 is set to open at m. Also, the stroke is set to about 1.2 mm, and the writing pressure, that is, the reaction force of the diaphragm member 13 or the like is set to rapidly increase. Therefore, in the stroke A, the opening 16 is not opened, that is, in a region where ink is not supplied, and in the stroke B, the opening 16 is opened and ink is supplied. Such settings correspond to various characters and the habits of writers.

That is, when writing, the writing, that is, the movement of the pen body is not started immediately after the pen body is brought into contact with the writing surface. There is a certain timing delay and the writing pressure becomes strong to some extent. Then the movement of the pen is started. Even in the case of a writer who has a weak writing pressure, the writing pressure when moving the pen, that is, writing, is about 70 g.
It is about. Further, in the case of the characteristic as shown in FIG. 10, the reaction force rapidly increases at a stroke of about 1.2 mm or more, and even in the case of a writer with a strong writing pressure, the area B to which this ink is supplied is Is set not to increase too much. Therefore, in both the case of a writer having a weak writing pressure and the case of a writer having a strong writing pressure, it is stroke B that moves the pen body and consumes ink.
The area of the stroke B does not change much in any case as described above. With such a setting, the density of the handwriting can be made almost the same regardless of whether the writing pressure is weak or strong.

The above-mentioned setting is based on the premise that many kanji, that is, the writing length for one stroke is relatively short, and that the pen body is completely separated from the writing surface for each writing stroke. There is. Therefore, when writing many characters with a long writing length such as English cursive, the above settings must be set separately according to the characteristics of these characters. Of course.
For example, in the case of a whiteboard marker used in the English-speaking world, it is preferable to widen the area of the stroke B. Further, it goes without saying that the above-mentioned settings are appropriately changed depending on the writing surface, the pen body, the type of ink, and the like.

The above reference example is the case of a whiteboard marker, and since this has no water absorption on the writing surface, the shade of the handwriting is greatly affected by the amount of ink supplied to the felt tip. It However, writing instruments that write on paper, felt-tip pens that use water-based ink, etc.
Since the shading of the handwriting is not so much influenced by the amount of ink supplied to the pen body, the timing of opening the opening does not need to be considered as strictly as in the case of the whiteboard marker described above.

11 and 12 show a writing instrument provided with an ink supply control mechanism 3a according to the first embodiment of the present invention. In this case, the protrusion height of the fitting protrusion 15a provided at the rear end of the slide holder 12 is such that the diaphragm member 1
The thickness is smaller than the thickness of 3a, and the fitting convex portion 15a does not penetrate the diaphragm member 13a. An opening 16a is formed in the center of the fitting convex portion 15a in the axial direction, and the opening 16a opens at the tip end surface of the fitting convex portion 15a. Further, in this embodiment, an opening 14a formed by, for example, a linear or cross-shaped cut is formed at the center of the diaphragm member 13a.

In the case of the first embodiment, when not writing, as shown in FIG. 11, the opening 14a of the diaphragm member 13a is tightly closed by the elastic force. Then, when written, as shown in FIG. 12, due to the elastic deformation of the diaphragm member 13a,
The opening 14a is opened so that the ink storage chamber 2 and the felt tip 4 communicate with each other.

In this embodiment, since the opening 16a is opened in the axial direction, there is an advantage that the structure of the mold becomes simple when the slide holder 12 is molded with synthetic resin or the like. It should be noted that this first embodiment has the same configuration as that of the above-mentioned reference example except for the above-mentioned points.
In 2, the parts corresponding to the reference example are denoted by the same reference numerals, and the description thereof will be omitted.

Further, FIG. 13 shows a second embodiment of the present invention. This is a hollow cylindrical holder portion 21 facing the tip side of the pen shaft 1 at the center of the diaphragm member 13b.
Is integrally projected, and the felt tip 4 is fitted and held in the holder portion 21. The holder portion 21 is formed so as to be movable in the axial direction with respect to the pen shaft 1. Therefore, when a writing pressure acts on the felt tip 4 by writing, the holder portion 21 retracts, and the diaphragm member 13b elastically deforms toward the ink storage chamber 2 side.
A notch-shaped opening 14b having a linear shape, a cross shape, or the like is formed at the center of the diaphragm member 13b. When the writing pressure does not act on the opening 14b, the opening 14b is closely attached and closed by the elastic force of the diaphragm member 13b. When deformed, the opening 14b is opened to connect the ink storage chamber 2 side and the felt tip 4 to each other.

The operation of the second embodiment is the same as that of the above-mentioned reference example or the first embodiment. In the second embodiment, since the diaphragm member and the holder portion can be integrally manufactured, the structure is simple, the manufacturing is easy, and the cost can be reduced.

Furthermore, the present invention is not limited to the above embodiments. For example, the present invention is not limited to a whiteboard marker, and can be generally applied to writing instruments such as a water-based felt tip pen, a water-based ballpoint pen, a paint marker, and a nail marker for applying nail polish. The pen body is not limited to the felt tip, any other pen body can be used, and the ink may be water-based, oil-based, alcohol-based or any other ink. Further, since the opening of the diaphragm member is notched, the ink does not flow out even when the slide holder and the pen body are removed from the diaphragm member in the case of the first embodiment. Therefore, it is possible to form the ink storage chamber and the diaphragm member separately from the pen shaft to form a replaceable ink cartridge.

[0047]

As described above, according to the present invention, the ink is mechanically and forcibly supplied from the ink storage chamber to the pen body in an amount corresponding to the amount of ink consumed for each writing, so that the operation is reliable. is there. Also, when ink is supplied, the slide plug slides, so the pressure inside the ink storage chamber does not rise above the pressure corresponding to the sliding resistance of this slide plug, and is always irrespective of the strength of the writing pressure. Can supply an accurate amount of ink. Further, in this writing instrument, since the ink supply amount does not depend on the ink suction pressure of the pen body, the type of ink, etc., the type of pen body and ink is not limited, and various types of pen bodies and ink can be used. Can be used. Further, the structure of the present invention has a simple structure and does not require so high precision in manufacturing, so that the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall vertical cross-sectional view of a reference example of the present invention.

FIG. 2 is a vertical cross-sectional view showing an enlarged part of the reference example.

FIG. 3 is a longitudinal sectional view showing a part of the reference example in another operating state in an enlarged manner.

FIG. 4 is a schematic view showing the operation of the reference example.

FIG. 5 is a schematic view showing the operation of the reference example.

FIG. 6 is a schematic view showing the operation of the reference example.

FIG. 7 is a schematic view showing the operation of the reference example.

FIG. 8 is a schematic view showing the operation of the reference example.

FIG. 9 is a schematic view showing the operation of the reference example.

FIG. 10 is a diagram showing an operation characteristic of the reference example.

FIG. 11 is a longitudinal sectional view showing an enlarged part of the first embodiment of the present invention.

FIG. 12 is a vertical cross-sectional view showing an enlarged part of another operating state of the first embodiment.

FIG. 13 is a longitudinal sectional view showing a part of the second embodiment in an enlarged manner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pen shaft 2 ... Ink storage chamber 3 ... Ink supply control mechanism 4 ... Felt tip 6 ... Slide stopper 12 ... Slide holder 13 ... Diaphragm member 14 ... Opening part 15 ... Fitting convex part 16 ... Opening

Claims (4)

(57) [Claims] 1. A pen shaft, an ink storage chamber formed in the pen shaft for directly storing liquid ink, and a liquid-tightly slidably provided inside the ink storage chamber for partitioning ink and air. At the same time, a slide stopper that slides in response to ink consumption, the ink storage chamber provided in the pen shaft and the tip end portion of the pen shaft are partitioned, and elastically deformed toward the ink storage chamber side. A diaphragm member made of an elastic material that reduces the inner volume of the ink storage chamber, and a pen body mounted on the tip end of the pen shaft so as to be movable in the axial direction of the pen shaft and a rear end of the pen shaft. A holder connected to a central portion of the diaphragm member, and a communication passage for supplying ink from the ink storage chamber to the pen body, and a central portion of the diaphragm member. When the diaphragm member is elastically deformed toward the ink storage chamber, the diaphragm member is provided with a notch-shaped opening for communicating the ink storage chamber with the communication passage. When writing pressure is applied during writing, the pen body moves backward together with the holder to elastically deform the diaphragm member toward the ink storage chamber side to pressurize the ink in the ink storage chamber and the diaphragm member. The writing instrument characterized in that the notch-shaped opening is opened so that the ink storage chamber and the communication passage are communicated with each other. 2. The diaphragm member is mounted in the pen shaft in a state of being compressed in a radial direction, and the pen body is retracted together with the holder to cause the diaphragm member to move to the ink reservoir. 2. The writing instrument according to claim 1, wherein the slit-shaped opening is opened after the chamber is elastically deformed to start pressurizing the ink in the ink storage chamber. 3. The holder is a slide holder slidable in the axial direction of the pen shaft, and a fitting protrusion is formed at a rear end portion of the slide holder. 2. The writing instrument according to claim 1, wherein the diaphragm member is fitted in the central portion of the diaphragm member without penetrating the diaphragm member to connect the rear end portion of the slide holder and the diaphragm member. 4. The writing instrument according to claim 1, wherein the holder is a holder portion integrally projecting from a central portion of the diaphragm member toward a tip end side of the pen shaft.