EP0822098B1 - Writing implement with fluid, whose reservoir is provided with anti-run dry system - Google Patents

Description

The present invention relates to a liquid ink writing article, in which ink is in the free state in a tank, not being trapped in a set of fibers constituting a fibrous reservoir. In such writing article, the ink is transferred from the reservoir to the head writing by a point called transfer point, the writing head which may constitute the end of said point. The present invention relates more particularly to a writing article of the aforementioned type which is equipped with an anti-defusing system which can also act as gauge to assess the amount of ink remaining in the tank.

A liquid ink writing article contained in a reservoir and with transfer point is described in particular in document EP.0.516.538. The body of the article has an interior partition which delimits, in the rear part, the tank for liquid ink. The rear end of the transfer point opens into the tank through said partition interior.

The defusing of such a writing article occurs when the transfer tip is no longer supplied with ink while the reservoir still contains liquid ink. This results in a stop writing which is of course an inconvenience for the user who in particular may think that the article is to be discarded while it still contains ink to use.

If we take into account the description and the drawings illustrating examples of how such a writing article is made in the document EP.0.516.538, it is understood that such a defusing can occur in the case of a use of the article points in the air and while a certain amount of ink has already been consumed. Since the rear end of the transfer point penetrates inside the tank only on a small distance, the ink remaining in the bottom of the tank no longer reaches this rear end when the item is positioned points in the air. Once all the ink contained in the transfer tip is consumed, there is defusing.

The same phenomenon can be observed also for a write with the article upside down but kept oblique when there is little ink in the tank.

The goal that the applicant has set is to offer an article of writing whose liquid ink is contained in a reservoir and is transferred from said reservoir to the writing head by a point capillary transfer, which overcomes the aforementioned drawbacks by being equipped with a anti-defusing system.

According to the invention, the transfer point extends over the entire height of the reservoir to the bottom thereof and the article includes a capillary element, which is mounted freely in the tank around the transfer point, the orifice of the capillary element being slightly oversized with respect to the tip transfer and the outer edge of the capillary element coming close the inner wall of the tank, so that when sliding along the tip transfers the capillary element to the surface the inner wall of the tank.

According to the principle of the invention, the capillary element is caused to move along the transfer point according to the position taken by article. When writing article is used in horizontal position or oblique, the internal edge of the orifice of the capillary element comes into contact with the outside of the transfer tip. The ink contained in the capillary element can thus diffuse in the transfer point to supply the writing head. As the ink in the element capillary is consumed by the transfer tip, the liquid ink which is constantly in contact with the diffuse capillary element therein and supplies ink to the writing tip.

Preferably the oversizing of the orifice of the element capillary is of the order of 0.2 to 0.8mm relative to the transfer point.

In a preferred embodiment, the transfer tip has a circular section of the order of 3.5 mm and the orifice of the capillary element has a diameter of the order of 4.5 mm.

Advantageously, the reservoir has a cylindrical shape with a diameter inside on the order of 14 mm and the capillary element has an external shape circular whose diameter is of the order of 13 mm.

To prevent the capillary element from becoming blocked along the tip transfer when the article is in an oblique position, it is important that said capillary element has a certain weight, which results in a thickness which is at least between 2 and 4mm.

In order to improve the sliding of the capillary element along the transfer point, the inner edge of the capillary element around the orifice is round. The absence of a ridge in the area of the orifice on the capillary element avoids the risk of it jamming on the transfer point when the article is kept oblique.

Being a transfer point in acrylic or polyester fibers or in an open pore sintered microporous material of the type polyethylene, the capillary element is preferably a microporous material open pore sintered polyethylene or polypropylene type.

Said capillary element can also act as a gauge or liquid ink level indicator in the tank when it has a lower density than that of liquid ink. For this it is necessary that the reservoir is at least partly transparent or translucent and that the hair element has a distinctive mark, distinguishing itself visually ink.

Since the capillary element is in constant contact with the liquid ink, it is distributed throughout the capillary volume of the element and therefore has the same color as the ink. To can be visually identified by the user, the capillary element must, for serve as a gauge, bear such a distinctive mark.

This mark may result from the presence of areas in which ink is missing. For example in the case of a capillary element produced from a sintered material with open pores, said zones are produced in the same sintered material but with closed pores. Ink cannot penetrate closed pore areas, so that said areas keep their original color while open pore areas take on the color of the ink.

• Les figures 1 et 2 sont des vues en coupe d'un article d'écriture connu en position d'écriture oblique pointe en haut pour la figure 1 et oblique pointe en bas pour la figure 2,
• La figure 3 est une vue schématique en coupe longitudinale d'un article d'écriture équipé du système anti-désamorçage,
• Les figures 4 et 5 sont des vues schématiques en coupe longitudinale et partielle du réservoir de l'article de la figure 3 en position horizontale pour la figure 4 et en position oblique pointe en bas pour la figure 5,
• La figure 6 est une représentation schématique partielle de côté de l'article de la figure 3, le système anti-désamorçage faisant office de jauge de niveau,
• La figure 7 est une représentation schématique partielle en perspective de l'élément capillaire à bord intérieur arrondi,
• La figure 8 est une vue en coupe transversale de l'article de la figure 4 selon l'axe VIII-VIII,
• et la figure 9 représente un élément capillaire constitué de deux éléments distincts à fonction respectivement de désamorçage et de repère visuel.

The present invention will be better understood on reading the description which will be given of an exemplary embodiment of a writing article with liquid ink and with transfer point, the reservoir of which comprises an anti-defusing system with a floating capillary element and sliding along the transfer point, illustrated by the attached drawing in which:

• FIGS. 1 and 2 are cross-sectional views of a known writing article in the oblique writing position pointing upwards for FIG. 1 and oblique pointing downwards for FIG. 2,
• FIG. 3 is a schematic view in longitudinal section of a writing article equipped with the anti-defusing system,
• FIGS. 4 and 5 are schematic views in longitudinal and partial section of the reservoir of the article of FIG. 3 in a horizontal position for FIG. 4 and in an oblique point-down position for FIG. 5,
• FIG. 6 is a partial diagrammatic side view of the article in FIG. 3, the anti-defusing system acting as a level gauge,
• FIG. 7 is a partial schematic representation in perspective of the capillary element with rounded internal edge,
• FIG. 8 is a cross-sectional view of the article of FIG. 4 along the axis VIII-VIII,
• and FIG. 9 represents a capillary element made up of two distinct elements with respectively defusing and visual cue functions.

FIGS. 1 and 2 show a writing article 1, the structure of which is already known from document EP.0.516.538. This writing article 1 consists of a substantially cylindrical hollow body 2, the rear part of which acts as a reservoir 3 for liquid ink 4. The reservoir 3 is closed by an internal partition 5 comprising a central orifice 6. The writing article 1 also consists of a transfer point 7 whose rear end 7 a opens into the reservoir 3 through the central orifice 6 and whose front end 7 b opens outside the body 2 forming the article writing head. The rear end 7 a of the transfer point 7 is force-fitted slightly into the central orifice 6 of the interior partition 5 so that the tightness of the reservoir 3 is ensured, but without crushing this end 7 a so that 'There may be circulation of ink and air through the tip 7. The transfer tip 7 is made of a material capable of ensuring the transfer of the ink by capillarity. It can be a felt made of acrylic fibers or compacted polyester.

Initially, when the writing article is new, the liquid ink 4 fills all or almost all of the reservoir 3. In this case, whatever the position of the writing article, the liquid ink 4 which is in the reservoir 3 comes into contact with the rear end 7 a and migrates by capillary action along this transfer point 7 to the front end 7 b forming a writing head. The use of the writing article results in a reduction in the volume of ink in the reservoir 3, and thereby in an increasing risk that the ink no longer comes into contact with the end 7 a of the transfer point 7, in which case what is called the defusing of the transfer point 7 occurs.

This defusing of the transfer point 7 causes writing to stop the fact that the ink no longer reaches the writing head, despite the presence liquid ink in the reservoir 3.

Figures 1 and 2 are shown as non-exhaustive examples two cases where the defusing of article 1 will occur.

According to figure 1 the article 1 is used point in the air in oblique. These include the use of this article 1 on a board or substantially vertical writing medium. The residual quantity of liquid ink 4 is not sufficient for the surface 4 ′ of the ink 4 in the reservoir 3 to reach the part 8 of the rear end 7 a closest to the ink 4. Once that the ink which is contained in the transfer point 7 is consumed, article 1 can no longer write, being defused. It is necessary to put the rear end 7 a of the transfer point back into contact with the ink 4 and wait for the ink to diffuse again into the transfer point from its rear end 7 a to the front end 7 b .

It is the same in the case illustrated in Figure 2 in which the article 1 is used upside down obliquely. It is a conventional use on a substantially horizontal support. In this case the quantity of ink 4 in the reservoir 3 is very low, its level 4 '' not reaching the part 9 of the rear end 7 a of the transfer point, which corresponds to the adjustment of this end 7 a rear in the central opening 6 of the inner wall 5. as defusing occurs so that there is a relatively small amount of ink, it is generally accepted that section 1 is discarded before all of the ink 4 is consumed.

The examples given in Figures 1 and 2 are not limiting. We can also observe a defusing of the transfer point 7 when the writing article is horizontal, and the ink level is not not sufficient to be in contact with the transfer tip. In addition, the defusing does not only occur during use, but can also occur during storage of the writing article. In this last case, prolonged storage of a writing article using ink based on pigments and having its point of defused writing results in evaporation of the solvent (s) from the ink contained in the tip transfer, while the ink pigments remain trapped in the capillary network of the transfer point and cause clogging damaging to this capillary network. As a result, the transfer point 7 irreversibly becomes inoperative, and the writing article cannot definitely no longer be used.

The object of the present invention is to provide a writing article of the type of FIGS. 1 and 2 which is equipped with an anti-defusing system and which thereby overcomes the aforementioned drawbacks. The system anti-defusing of the invention, an alternative embodiment of which goes to present to be described, allows continuous feeding of the transfer tip by liquid ink regardless of how the item is used or stored after use and moreover allows to consume almost all the ink in the tank.

In order to be equipped with the anti-defusing system of the invention, section 10 (Figure 3) is provided with a transfer rod 11 which extends over the entire height of the container 12, its end 11a up to bottom 12 a of it. The anti-defusing system proper consists of a capillary element 13 which is made of a material allowing the diffusion of the ink by capillary action as is the case with the transfer tip 11. This capillary element 13 is provided with an orifice 14 which is shaped to allow the passage of the transfer point 11. As it is in particular a transfer point 11 of circular section, the orifice 14 also has a circular shape, with a diameter slightly greater than that of the point transfer 11.

Furthermore, the edge 13 is most outside of the capillary member 13 has a configuration which is similar to that of the inner wall 12 b of the reservoir 12, but slightly undersized.

In the example illustrated in FIG. 3, the capillary element 13 has a cylindrical shape, of small thickness e , pierced axially to form the orifice 14. When it is placed around the transfer point 11 to inside the reservoir 12, the element 13 can slide naturally along the rod 11, due to the play existing respectively between its outer edge 13 a and the internal wall 12 b of the reservoir 12 and its inner edge 13 b and the transfer tip 11.

In the case where the capillary element 13 is also used as level indicator, it is necessary that the capillary material constituting element 13 is less dense than liquid ink 15. In this case, as shown in Figure 3, the capillary element 13 floats on the surface of the ink 15 contained in the tank 12. Of course, it is also conceivable in the context of the invention, to use an element 13 whose density is higher than that of the ink used, so that the element 13 is completely immersed in the liquid ink 15. In this case, the element 13 does not act as a level indicator.

When the article 10 is in the state illustrated in FIG. 3, the capillary element 13 has no function, since the ink 15 is directly in contact with the transfer point 11 and can therefore supply this transfer point up to at its front end 11 b acting as a writing head. The only possible use of element 13 is to serve as a level indicator as will be explained below.

Figures 4 and 5 illustrate two use cases in which the capillary element 13 fulfills its function of anti-defusing system.

The amount of ink 15 remaining in the article reservoir 12 writing 10 is such that in a horizontal position the level 15 ′ of the ink 15 in the tank 12 does not reach the transfer tip 11 (Figure 4).

When the article 10 is in this horizontal position, the capillary element 13, which is positioned transversely to said transfer point 11, is suspended vertically thereon. More specifically, a zone 13 c of the inner edge 13 b of the capillary element 13 is in contact with a zone 11 c of the transfer point 11, as illustrated in FIG. 8. In this figure, the diameter differences can be better seen , corresponding to the oversizing of the capillary element 13 relative on the one hand to the transfer point 11 (inner edge 13 b ) and on the other hand to the reservoir 12 (outer edge 13 a ).

In an exemplary embodiment, the transfer tip 11 had a diameter of 3.5 mm, the capillary element 13 had an orifice 14 having a 4.5 mm diameter, freeing an oversize of 1 mm, while that the reservoir 12 had an internal diameter of 14 mm and the element capillary 13 had an outside diameter of 13 mm corresponding to a oversized by 1 mm.

The anti-defusing operation is as follows. The lower part of the capillary element 13 plunges into the liquid ink 15 which migrates throughout the capillary network of the element 13. The ink contained in this capillary network can itself migrate into the transfer tip 11 through the intermediate of the zones 13 c and 11 c respectively of contact between the capillary element 13 and the transfer tip 11. It is of course necessary that the capillarity of the capillary network of the element 13 is sufficient to allow such diffusion in this zone. It should also be noted that, unlike what is illustrated in FIGS. 4 and 8, it would also be possible, within the framework of the invention, to use an element 13 which has a sufficiently low density compared to that of the ink so that the element 13 is supported only by the liquid ink, the contact areas 11 c and 13 c being in this case located at the respective lower parts of the transfer tip 11 and the inner edge of the element 13.

Being a transfer point 11 made from fibers acrylic or polyester or possibly from a material microporous sintered with open pores, the capillary element 13 is preferably made from a pore-sintered microporous material open. More particularly, the porosity of the capillary element 13 will be between 30 and 70%. Preferably, it will also be a material polyethylene or possibly polypropylene, which allows reduce the coefficient of friction of element 13 on the transfer point, and therefore to facilitate the sliding of the element 13.

Advantageously, the hydrophilic nature of the capillary element 13 relative to the ink used, adding in a first variant an agent making it possible to reduce the surface tension of the ink. More particularly as an agent, a non-ionic surfactant such as Nonyl-phenol-ethoxylated marketed by Union-Carbide under the brand TERGITOL®, or as an amide fat marketed by SEPPIC under the brand ORAMIDE®, or even such as a polysiloxane marketed by the company BYK CHEMIE under the BYK® brand.

The amount of agent used will obviously depend on the voltage of intrinsic surface of the ink used and of the type of constituent material the hair element. For information only, taking into account the voltage of usual area of inks commonly used to date, when the capillary element 13 is made of a microporous material sintered to open pores in polyethylene or polypropylene, add in volume about 1% of agent based on the total volume of the ink.

In a second variant which can be combined with the first aforementioned variant, the hydrophilic nature of the capillary element is improved 13 compared to the ink used, by subjecting the constituent material element 13 a treatment making it possible to increase the surface energy of this material. It will more particularly be an oxidizing plasma treatment or a treatment by depositing a surfactant on the element capillary.

In the example illustrated in Figure 5, very little liquid ink remains 15 in tank 12. When item 10 is used upside down oblique, as illustrated, the level 15 '' of this ink 15 does not reach the transfer tip 11. The capillary element 13 is lowered, by sliding along the transfer point 11, until reaching the internal wall 16 closing the front of the tank 12, so that its lower part dips into the ink liquid 15 and allows it to diffuse into the capillary network of element 13 as far as transfer point 11.

So that this sliding along the transfer point 11 is possible, without risk of jamming of the capillary element 13 at an intermediate level which would prevent the capillary element from being in contact with the liquid ink, it is preferable that the inner edge 13 b of the element 13 does not form an edge but has a rounded shape as shown in Figure 7. in another variant, it is also contemplated that the outer edge 13a of the element 13 also presents a round shape.

In addition it is desirable that the capillary element 13 has a weight sufficient to be made to slide along the transfer point 11 during the use of section 10 in an oblique position, even for low tilt angles. Preferably for this the thickness e of the capillary element is between 2 and 4mm.

When the capillary element 13 is also used as level indicator, it is important on the one hand that the reservoir 12 is made in a material which is transparent or at least translucent on at minus one of the sides of the tank which extend parallel to the tip transfer 11. We could for example provide on one of these faces a window making the whole height of the tank 3, but of limited width. he on the other hand, the material constituting the capillary element 13 must be less dense than liquid ink 15. This is obtained in particular by using a sintered porous material with open pores based on polyethylene or polypropylene.

Furthermore, so that the user can visualize the level where the capillary element 13 is located, the outer edge 13 a thereof is for example provided with a distinctive mark, able to be perceived visually by the user at through the tank wall 12.

This distinctive mark makes it possible to make the separation between the liquid ink and the ink which permeates the capillary network of the element 13. Such a distinctive mark can consist in streaks 17 which are for example obtained by using on the outer edge 13 has the same constituent material of the capillary element 13 but with closed pores and not open pores. Being a microporous sintered material, this formation of streaks can be obtained by locally overheating the microbeads in the sintering mold so that in the corresponding zones the microbeads agglomerate without forming a capillary network. Thus the ink does not penetrate into areas with closed pores while it penetrates into areas with open pores. The pore portions form closed grooves 17, visible on the outer edge 13a of the capillary element 13.

In another variant illustrated in FIG. 9, the capillary element 13 could be made up of two separate elements superimposed, a first 13 'capillary element with anti-defusing function and a second element 13 '' non-capillary with visual cue function. The non-capillary element 13 '' will for example consist of a pellet made of a material hydrophobic, and the two elements 13 'and 13' 'can be assembled by any suitable means, in particular by heat sealing or bonding.

The present invention is not limited to the embodiment which has been given as a non-exhaustive example. In particular the transfer tip 11, the capillary element 13 and the reservoir 12 can have other shapes than those described above. It is enough that on the one hand the capillary element can slide freely between the bottom of the tank and the internal wall closing the front of it and on the other hand the capillary element can transfer the ink to the transfer point facing the contact areas. In particular the contact areas can be increased by using a transfer point, and thereby an orifice for the capillary element, which is polygonal and no longer circular.

Claims (13)

1. A writing instrument (10) having liquid ink (15) contained in a reservoir (12) and transferred from said reservoir (12) to a writing tip via a capillary transfer rod (11), the instrument being characterized in that the transfer rod (11) extends over the full height of the reservoir (12) to the far end (12a) thereof, and in that it includes a capillary element (13) mounted around the transfer rod (11) to move freely in the reservoir (12), the orifice (14) of the capillary element (13) having dimensions slightly greater than those of the transfer rod (11) and the outside edge (13a) of the capillary element (13) coming into the immediate vicinity of the inside wall (12b) of the reservoir (12) in such a manner that the capillary element (13), as it slides along the transfer rod (11), comes substantially flush with the inside wall (12b) of the reservoir (12).
2. An instrument according to claim 1, characterized in that the orifice (14) of the capillary element (13) is about 0.2 mm to 0.8 mm greater in size than the transfer rod (11).
3. An instrument according to claim 1 or 2, characterized in that the transfer rod is circular in section having a diameter of about 3.5 mm, and the orifice of the capillary element has a diameter of about 4.5 mm.
4. An instrument according to any one of claims 1 to 3, characterized in that the reservoir (12) is cylindrical in shape, having an inside diameter of about 14 mm, and the capillary element (13) is circular in shape, having an outside diameter of about 13 mm.
5. An instrument according to one of claims 1 to 4, characterized in that the thickness (e) of the capillary element (13) lies in the range 2 mm to 4 mm.
6. An instrument according to claim 1, characterized in that the inside edge (13b) of the capillary element (13) around the orifice (14) is rounded.
7. An instrument according to claim 1, characterized in that, for a transfer rod (11) made of acrylic fibers or of polyester, or of a polyethylene type open-pore sintered microporous material, the capillary element (13) is made of a polyethylene or polypropylene type open-pore sintered microporous material.
8. An instrument according to claim 1 or 7, characterized in that to improve the hydrophilic nature of the capillary element (13) relative to the ink used, an agent is added to the ink for reducing the surface tension of the ink.
9. A writing instrument according to claim 8, characterized in that the agent is a non-ionic surface-active agent.
10. An instrument according to any one of claims 1, 7, 8, and 9, characterized in that to improve the hydrophilic nature of the capillary element (13) relative to the ink used, the material of the capillary element (13) is subjected to treatment enabling its surface energy to be increased, and more particularly to oxidizing plasma treatment or to deposition of a surface-active agent.
11. A writing instrument according to claim 1, characterized in that the reservoir is transparent or translucent, at least in part, and the capillary element (13) has a density that is less than that of the liquid ink (15), and has distinctive marking (17) that can be visibly distinguished from the ink (15).
12. An instrument according to claim 11, characterized in that for a capillary element (13) made of an open-pore sintered material, the distinctive marking corresponds to zones made of the same sintered material but having closed pores.
13. An instrument according to claim 11 or 12, characterized in that the capillary element (13) is made up of two separate superposed elements, a capillary first element (13') for preventing loss of priming and a non-capillary second element (13'') acting as a visible marker.

Images