DE102009040704A1 - Nib for writing utensil i.e. fountain pen, has groove extending from initial point up to stylus for transporting ink from initial point to stylus, and exhibiting gradient with certain width reduced from initial point to stylus - Google Patents

Abstract

The nib has a groove extending from an initial point up to a stylus for transporting ink from the initial point to the stylus. The groove exhibits a gradient with a certain width reduced from the initial point to the stylus. A condition and/or topography of the groove remains unchanged during variation of strength of writing force applied on the nib. The groove exhibits a rectangular cross-section perpendicular to an extension along the nib. The stylus exhibits a writing corn made of a carbide metal. The nib is made of metal e.g. steel or gold. An independent claim is also included for a method for producing a metallic nib.

Description

The invention relates to a writing pen having the features according to the preamble of claim 1. Furthermore, the invention relates to a method for producing a nib according to the preamble of claim 16.

One of the most important product features of a writing instrument, especially a fountain pen, is its writing feel. Particular attention is paid to the subjective assessment of a "soft" or "hard" typing feeling. A soft typing feel is defined as a sliding, resistance-free and quiet writing on different types of paper. A hard typing experience is just the opposite. Too loud a letter can be very disturbing and unpleasant. A loud writing noise can be compared with the mechanical treatment of materials such as saws, planing or brushing. Also, a resistance-loaded letter is very uncomfortable. You have the feeling that you are wedged in paper with the fountain pen or stuck to the fibers of the paper. Since each person has his own writing style and his own writing posture, there are different variations of writing angle, writing pressure or typist, twist angle of the nib and the sense of noise.

The spectrum of most commonly used writing angles ranges from 40 ° to 70 °. If you write with a writing angle greater than 45 °, the fountain pen is pressed in pushing traffic against the ink conductor, so that no more free springs is possible. By this breakaway of the fountain pen in the push traffic a disturbing noise is generated. From a sound level of 30 dB, this noise triggers a psychic reaction, which can be expressed in irritation and annoyance. As well as the writing angle also varies the writing pressure from person to person. Typical typists are between 0.4 and 5 N. The higher the writing pressure, the harder the writing experience of the writer. Soft writing is usually felt at low writing pressure. In extreme cases, too high a writing pressure may spread the pens' spring legs too far so that the ink shoots back toward the ink conductor. This occurs when the ink can no longer be transported by capillary action to the writing grain as the capillary, the slot, becomes too large.

Twisting a slotted quill one of the nibs is subjected to a higher writing pressure than the other, so that it can generate more vibrations because it does not act on the paper with the same writing pressure. As a result, the unpolished writing grain inside this writing pen leg touches the sheet and then hooked in the paper. This snagging or sticking also causes an uncomfortable and hard typing feeling, in which the above-mentioned noises can be distracting.

In the document DE 38 34 706 A1 For example, a writing pen for writing with liquid ink made of a ceramic material to achieve a narrow range of production tolerance is described. The nib described has a recessed, leading to the nib, open to the bottom ink channel.

The object of the present invention is to provide a nib with a soft typing feel.

This object is achieved by a nib with the features of claim 1 and / or by a method for producing a nib with the features of claim 16. Advantageous developments of the invention are characterized in the dependent claims.

An inventive nib for a writing instrument, in particular a handwriting device, preferably an ink pen, consists of a metal, in particular a steel or gold. It has, according to the invention, a writing tip and a groove extending from a starting point on the nib to the nib for transporting ink from the starting point to the nib.

Advantageously, a scratch-resistant write characteristic is achieved with the pen according to the invention. The writing feeling is soft. During the writing arise few, preferably no disturbing noises.

The nib is preferably slotless, without a capillary in the form of a slot, in particular according to the invention, the groove may be provided instead of a slot in the nib.

In advantageous embodiments, the groove has a profile with a tapering width from the starting point to the writing tip. Further, or alternatively, the state and / or topography of the groove may remain unchanged as the amount of writing force applied to the nib varies. In other words, the shape of the groove is independent of the writing force or variation in the strength of the typist.

A pen according to the invention may comprise the following further features individually or in combination (in part or in whole):
The edges of the groove may have a straight course from the starting point to the writing tip. The groove may have a substantially rectangular cross-section perpendicular to its extent along the nib. The groove may be located on a lower side of the nib.

The writing tip may have a writing grain of a hard metal, in particular of iridium, ruthenium or an alloy having one of these elements. The writing grain of the pen can be slick. The writing grain may have a groove for transporting ink, in particular, this groove may be provided instead of a slot.

The groove in the writing grain can represent the continuation of the groove in the nib. The quill pen can be cardiac-free.

In the context of the invention is also a writing instrument, in particular a handwriting device, preferably an ink writing device, for example a fountain pen. According to the invention, such a writing instrument on a nib with one or more features according to this description. In other words, a writing instrument according to the invention comprises a writing pen according to the invention. In particular, the writing instrument may include an ink reservoir and an ink guide having at least one ink channel for transferring an ink from the ink reservoir to the nib.

In the inventive method for producing a nib from a metal, unslotted (slotless) spring blank, wherein the nib or the spring blank has a writing tip, a groove in the spring blank is excluded from a starting point on the nib to the nib by laser ablation.

In an advantageous embodiment of the method according to the invention, an unslotted writing grain made of a galvanized hard metal is welded to the writing tip. The groove in the spring blank is excluded after welding the writing grain. It can also be excluded in the writing grain a groove by laser ablation.

In the method according to the invention, the laser ablation preferably takes place by irradiation of laser pulses with a pulse duration shorter than 1 ns (nanosecond). In other words, according to the invention, a picosecond laser is used.

By means of a plurality of laser pulses, in the method according to the invention, an ablation can be carried out in such a way that the depth and / or width of the groove to be taken out are designed to be spatially variable.

Further advantages and advantageous embodiments and developments of the invention will be described with reference to the following description with reference to the figures. Embodiments of the pen according to the invention may have the features described individually or in each case a subset of the described features or all features in combination with each other. Embodiments of the method according to the invention for producing a nib may comprise the described steps individually or in each case a subset of the described steps or all steps in combination with one another.

A. Construction and general function of a fountain pen

In the in the 1 shown embodiment of a writing instrument (fountain pen with a slotted, metal nib according to the prior art) of the fountain pen consists of several different components: nib, also referred to as fountain pen, ink, spring sleeve, ink cartridge or converter (for filling from an inkwell), container , Cap.

• • Verfahrensschritte der Herstellung mittels Produktionsautomat
• – Herzloch ausstanzen
• – planaren Federrohling ausschneiden
• – vordefinierten Walzverlauf vornehmen
• – Biegestempel biegen den planaren Federrohling in endgültige Form
• – Anschweißen des galvanisierten Hartmetallkorns an die Federspitze
• • Vorpolitur
• • Materialabtragung zur Definition der Schreibfläche
• • Trennscheibe zur Schlitzung der Füllhalterfeder
• • Politur und Kantenverrundung der Füllhalterfeder
• • Setzen der Füllhalterfeder mit Hilfe eines thermischen Lasers
• • Hochglanzpolitur
• • Säure-Lauge Bad zur Erhöhung der Korrosionsbeständigkeit

The fountain pen is preferably made of either stainless steel or 14k gold. This, in the case of the steel spring, is produced by means of a production machine with the following production steps:

• • Process steps of production by means of production automat
• - punch out the heart hole
• - Cut out the planar spring blank
• - Make predefined rolling process
• - Bending stamps bend the planar spring blank into final shape
• - Welding the galvanized hard metal grain to the spring tip
• • Prepolishing
• • Material removal to define the writing surface
• • Cutting disc for slotting the fountain pen spring
• • Polishing and edge rounding of the fountain pen spring
• • Place the fountain pen using a thermal laser
• • high gloss polish
• • acid lye bath to increase corrosion resistance

The steel strip is fed to the production machine and brought in various steps in the final form of a fountain pen. This predefined rolling, cuts and bends are made. As the last step of the production machine, a galvanized hard metal grain is welded to the tip of the fountain pen.

In a specific embodiment, the writing grain may consist of a ruthenium alloy and / or comprise iridium. It is preferred to use a stainless steel.

After the fountain pen spring has been provided in the final form and with a carbide grain, it is pre-polished. The writing grain is polished to a predefined shape and to predefined dimensions. Also, in this production step, a writing surface is attached to the grain to promote the soft typing feel. Thereafter, the fountain pen spring according to the prior art is provided with a slot. For this, it is clamped in a machine and processed with the help of a cutting disc. Since this production step causes sharp edges on both the scribe and the strip, they are subsequently removed by various grinding and polishing operations, and the edges in the scribe are rounded accordingly. Standard edge rounding is defined as 0.02 mm to 0.05 mm. One of the last production steps is the so-called setting. In this step, the springs are irradiated at defined points with a laser to create the taper of the slot. With a fountain pen set, ink is released only by the writing pressure. This opens only by the writing pressure. After rejuvenating the nib, it is polished to a high gloss.

There are different spring tip widths, which range from EF (extra fine, 0.44 mm to 0.5 mm), F (fine, 0.57 mm to 0.64 mm), M (medium, 0.73 mm to 0.82 mm) mm) to B (wide, 0.95 mm to 1.10 mm) and BB (extra wide, 1.20 mm to 1.30 mm).

In the 2 (Top view of an embodiment of a pen nib according to the prior art) is an embodiment of a fountain pen in plan and in the 3 shown in the bottom view. In the 3 (Bottom view of an embodiment of a writing pen with line width M according to the prior art) are recognizable: a heart hole, the tapered, continuous slot from the heart hole to the writing grain, the writing grain of hard metal.

In the 4 an embodiment of an ink guide is shown. The ink conductor is made of plastic and can be dismantled. The ink guide is used to transport the ink from the ink cartridge to the fountain pen. The part of the ink guide which is inserted into the ink cartridge is called a mandrel sleeve. This pierces the ink cartridge and passes the ink on. From the mandrel sleeve to the tip of the ink conductor are two ink channels, which transport the ink with the aid of the capillary effect to the front. The wedge covers these two ink channels, which have dimensions in the tenth of a millimeter range, and serves as a riser channel in the compensation chambers. The lateral equalization chambers are semi-capillary and connected to the two ink channels. These compensation chambers serve as an ink reservoir and as an air passage in the ink cartridge. On the underside of the ink conductor is the air duct, which is open towards the front. This air channel extends to the end of the mandrel sleeve. The fountain pen spring is attached to the tip of the ink guide. This is stuck on the ink conductor non-positive and positive. Thus, the fountain pen spring is connected to the ink conductor and the ink can flow.

The spring sleeve envelops the ink conductor and closes the open compensation chambers to the outside. The ink conductor is inserted from the front into the spring sleeve. If the smooth assembly of the ink conductor is done, the so-called spring assembly is made (see 5 , An embodiment of a spring unit, which also serves as a handle).

The ink cartridge or the converter are used for ink delivery to the mandrel sleeve. From there, the ink is transported through the capillary ink channels of the ink guide to the fountain pen. The converter is designed for manually refilling the ink from an inkwell. The container is connected by means of a screw cap with the spring sleeve. By screwing the container to the spring sleeve, the ink cartridge is pressed against the mandrel sleeve. Turning the container form-fitting to the spring sleeve, the ink cartridge is opened. The cap is used to protect the fountain pen against drying out and damage. This is composed of an inner and outer cap. The outer cap is a plastic component, while the inner cap is elastic. By attaching to the spring sleeve seal the cap and the spring sleeve, the fountain pen and the ink conductor. A complete seal is avoided, otherwise condensate would form on the fountain pen. Therefore, a small but defined leak in the cap is generated to prevent the formation of the condensate. However, the air permeability is so low that a drying out of the fountain pen or the ink conductor practically does not take place.

The inks used in the writing instruments consist of completely dissolved dyes, so no pigments. Furthermore, they contain necessary solvents, small amounts of acids, preservatives and humectants. The following guidelines apply to the inks: • PH value: between 2.0 and 9.5 Surface tension: 45 to 65 mN / m • viscosity: ~ 1 mPa · s • Density: 1 kg / dm ³

The water content is about 95%. If the ink does dry out, the dyes and some solvents will be left behind. This remainder, depending on the color, is about 2% to 6%.

For the functioning of the fountain pen:

In the 6 an operative embodiment of a writing instrument is shown.

In normal writing down with the writing tip, the ink flows from the ink cartridge to the fountain pen, more specifically from the ink cartridge into the mandrel sleeve and thence through the two capillary ink channels to the fountain pen. The writing pressure opens the tapered slot and the ink flows from the two ink channels to the writing grain. As much ink flows out of the ink cartridge until the air negative pressure built up inside the ink cartridge is in equilibrium with the weight of the ink column. The entire inner cross section of the mandrel sleeve is filled with ink. This control process is called ink braking. The excessive amount of ink discharged during this process does not drip off but passes from the ink channels, via the riser channels, into the equalization chambers. These fill up from below and begin with those of the fountain pen closest. The thereby displaced air is guided via the air duct to the outside. When writing, the ink from the equalization chambers is consumed first. This is transported from the compensation chambers via the riser channels back into the ink channels and on to the fountain pen. Only when this supply is used up from the compensation chambers, the system gets new ink through the ink channels from the mandrel sleeve and thus from the ink cartridge. In this case, the ink is replaced by the air in the rectangular cross section of the mandrel sleeve (0.7 mm x 1.4 mm). Thus, the ink brake is degraded. Now get small amounts of air from the air duct in the ink cartridge and thus reduce the negative pressure. Thereafter, the process starts again.

B. Embodiments and methods of manufacturing a nib according to the invention

According to the invention, a groove is provided in the underside of a fountain pen. This can be straight or tapered (conical).

The following goals are to be achieved: soft writing, no annoying writing noise, optimal ink flow, no writing problems, almost complete reproducibility result, faster production, more accurate processing, savings in production, fewer production steps and / or production facilities, shorter lead times, increased process reliability.

• • Beim Pikosekundenabtrag ist die Physik des Abtrags im Vergleich zu längeren Pulsen (wie z. B. beim Nanosekundenlaser) anders
• • Zuerst wird die Energie des Laserpulses absorbiert und dann tritt die Verdampfung bzw. die Plasmabildung des abgetragenen Materials ein
• • keine Schmelzbildung
• • bessere Abtragsqualität
• • Genauerer Abtrag

With the help of a picosecond laser groove geometry is introduced into the fountain pen. According to the invention a groove - both in the steel of the nib and in the writing grain - introduced with the picosecond laser. The following advantages result from the material removal with a picosecond laser:

• • For picosecond erosion, the physics of erosion are different compared to longer pulses (such as nanosecond lasers)
• • First, the energy of the laser pulse is absorbed and then the evaporation or the plasma formation of the eroded material occurs
• • no melting
• • better removal quality
• • More exact removal

When using a nanosecond laser, unlike the picosecond laser, a greater amount of enamel formation would occur, resulting in an ejection at the processed edges. Melting on the inside edges of the writing grain would result in a hard writing sensation. This disadvantage was avoided by the use of a picosecond laser in an advantageous manner.

With peak intensities of more than 10 W / cm ^{2 of} a picosecond laser, almost all materials are vaporized before they can form a melt. With the help of picosecond lasers an accuracy of less than 5 μm and a surface roughness of less than 0.5 μm of the machined workpiece can be achieved.

In a number of designs, the fountain pens have been provided with a straight groove. This had a groove width of 0.2 mm and a groove depth of 0.2 mm. The resulting grooves were measured. In particular, the positions heart hole (point 3), channel (point 2) and point (point 1) are considered: 7 , An inventive embodiment of a slotless fountain pen spring with groove on the bottom.

In the laser processing of the writing grain two distinctly different Nutformen were realized in the writing grain: on the one hand the writing grain was provided with a straight, in particular rectangular channel and on the other hand, a round channel, which corresponds to the spherical shape, lasered into the writing grain. The groove depth was about 192.5 μm in the straight channel. The groove width was about 225.7 microns. The length of the groove was about 924.7 microns. For a good ink flow, a planar groove bottom is preferred and advantageous. For a round ink channel shape, the edges were much more defined than for a straight ink channel shape. The groove depth in this case was 121.4 μm. The more the groove shape resembles a rectangular shape, the more the capillary effect comes into its own.

The resulting nibs, which were neither polished nor padded, were subjected to writing tests. After a brief cover letter or a single immersion in an inkwell, all fountain pen springs wrote. With the fountain pen springs produced according to the invention, there were no ink drops, a continuous typeface was obtained. The pleasant writing experience is due to the rounded shape of the inner edges and the uniformity of these. Although occasionally disturbing noises, but these were at a bearable level. The origin of the disturbing noises depends directly on the nature of the inner edges of the writing grain, so that the noise was attributed to the lack of polish.

With unchanged groove depth of 0.2 mm, a number of embodiments were made with different groove shapes. In addition to straight grooves, a conical, tapered groove shape was also produced in individual nibs by means of laser processing. This conicity is to promote the capillary effect even more, so that the ink flow is improved. The heart hole is the largest and before the writing grain the smallest groove width. Here also different groove widths were defined in the writing grain. It should be noted that the groove width in the writing grain could not be arbitrarily small. The narrower the groove should be, the less material can be removed.

Specifically, the following parameters were investigated for grooves in the pen nib and in the writing grain, which in the 8th and 9 are shown: In the 8th a series of writing nibs according to the invention with straight groove, in the 9 a series of pen nibs according to the invention with tapered groove.

A narrower groove in the writing grain tends to reduce the writing noise. By contrast, the larger the groove width, the more ink is available to the writing grain to produce a continuous typeface. The groove widths are larger than the grain widths: this should guarantee a sufficient ink supply.

The 10 . 11 and 12 show an embodiment of a nib of variant A with 0.07 mm grain width and 0.3 mm groove width: 10 at the heart hole, 11 in the canal, 12 at the top.

The 13 . 14 and 15 show an embodiment of a nib of variant b with 0.07 mm grain width and 0.3 mm groove width: 13 at the heart hole, 14 in the canal, 15 at the top.

The resulting nibs were subjected to writing tests. After a brief cover letter or a single immersion in an inkwell, all fountain pen springs wrote. With the fountain pen springs produced according to the invention, there were no ink drops, a continuous typeface was obtained.

In the first step, the fountain pen springs were written unpolished. An improved write behavior was observed especially in the fountain pen springs with a narrower groove in the grain. The wider the groove in the writing grain, the harder the writing feeling was. With a groove in the writing grain, the inner edges of the fountain pen spring can more easily get caught in the paper or dislodge a single fiber from the paper. The wider this groove in the writing grain, the more the inner edges have a direct effect on the typing and the noise.

In order to assess the effects of the mechanical polish and the writing surface on the writing and the disturbing noises, the writing surface was removed on all fountain pen springs and the mechanical polishing was carried out. The inside edges were provided with standard edge rounding, from 0.02 mm to 0.05 mm. The illustrations above show these fountain pens. It can be seen that the ink channel still reaches into the writing grain. This is to cause a higher amount of ink in the writing grain. Ink delivery also plays an important role in writing. If the fountain pen pen emits a lot of ink, it slides more easily over the paper and reduces the writing resistance. Each fountain pen slides on a so-called ink lake.

While writing with the fountain pens, only very little writing resistance was felt. This fact is attributed to the higher ink delivery, mechanical polish and writing surface. The writing was consistently very pleasant with all fountain pens. Also, very rarely were any sounds. However, these were only rarely classified as disturbing. This significant improvement in writing performance can be attributed to the even smaller groove in the writing grain, the polish and the writing surface. Thus, this series of embodiments has shown that the typing feel can be improved. Also, the disturbing noises can be reduced or even regarded as not disturbing.

An embodiment of a writing pen according to the invention is in the 16 . 17 . 18 and 19 shown.

16 : View of an embodiment of a writing pen according to the invention.

17 : Rotated view of an embodiment of a nib of the invention.

18 : Top view of an embodiment of a writing pen according to the invention.

19 : Bottom view of an embodiment of a writing pen according to the invention.

In comparison of a nib according to the prior art to a nib of the invention in the same geometry shows that the nib of the invention less flexes at the same writing angle and at the same writing pressure. Also, the nib of the present invention causes less comparative voltages than those of the prior art at the same writing angle and writing pressure.

Due to the closed shape of the writing pen according to the invention, the writing pressure and writing angle affects less on the deflection and the comparison voltages. Although the nib of the invention deflects less, it is subjectively classified as softer. Thus is the prevalent assumption that a soft typing feel can only be achieved with two separate fountain pen nibs to allow for resilient writing is considered incorrect. Due to the closed shape, the inner edges of the writing grain can no longer or only minimally get caught in the surface of the paper. This results in a quieter writing noise. The presumption that a soft writing feeling directly depends on the ink delivery has been confirmed in the writing test. The fountain pen spring of the prior art has a hard writing feel due to a high writing pressure. This high writing pressure causes the fountain pen nib to spread further. In principle, this spreading still allows ink to be transported to the writing grain, but only to a lesser extent. The wider the capillary, in the prior art, the slot, the slower the ink flows to the writing grain, since the capillary effect still exists, but has decreased in its effect.

In summary, it should be noted that was completely omitted in the considered embodiments of the pen of the invention on a continuous slot. Instead, a groove, tapered (conical) or straight, was inserted into the steel and into the writing grain. This was achieved with the help of laser technology. This groove had a depth of about 0.2 mm. The width of the groove was varied. It has been ensured a steady supply of ink. After a mechanical polish a soft and resistant writing feeling was achieved. Also, the noise during writing was at a very good low level. This can be attributed to the waiver of the separation of the nib by means of a slot. By introducing the groove in the nib this is no longer as susceptible to vibration as the previous with slot. As a result, vibration-induced noise was reduced, preferably completely excluded. Also, the ink delivery was very satisfactory.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3834706 A1 [0005]

Claims (20)

Writing pen for a writing instrument, made of a metal and having a writing tip, characterized by a groove extending from a starting point on the nib to the writing nib for transporting ink from the starting point to the nib. Quill pen according to claim 1, characterized in that the nib is slit-free. Quill pen according to claim 1, characterized in that the groove has a course with tapering from the starting point to the writing tip width. Feather according to claim 1, characterized in that the state and / or the topography of the groove remain unchanged with variation of the strength of a writing force applied to the nib. Feather according to claim 1, characterized in that the edges of the groove have a straight course from the starting point to the writing tip. Quill pen according to claim 1, characterized in that the groove has a substantially rectangular cross-section perpendicular to its extent along the nib. Feather according to claim 1, characterized in that the nib has a bottom and that the groove is located on the underside of the nib. Quill pen according to claim 1, characterized in that the writing tip has a writing grain made of a hard metal. Quill pen according to claim 1, characterized in that the writing grain is slotted. Writing pen according to claim 1, characterized in that the writing grain has a groove for transporting ink. Quill pen according to claim 1, characterized in that the groove in the writing grain represents the continuation of the groove in the nib. Quill pen according to claim 1, characterized in that the metal is a steel or gold. Quill pen according to claim 1, characterized in that the quill is herzlochlochfrei. Writing utensil, characterized by a nib according to one of the preceding claims. Writing implement according to claim 14, characterized in that the writing instrument comprises an ink reservoir and an ink guide having at least one ink channel for transferring an ink from the ink reservoir to the nib. A method of making a nib from a metallic, unslotted spring blank, the nib having a nib characterized by excluding a groove in the nib from a starting point on the nib to the nib by laser ablation. A method for producing a nib according to claim 16, characterized in that an unslotted writing grain made of a galvanized cemented carbide is welded to the writing tip and that the exclusion of the groove in the spring blank takes place after welding the writing grain. A method for producing a nib according to claim 17, characterized in that in the writing grain also a groove is excluded by laser ablation. A method for producing a writing pen according to any one of claims 16 to 18, characterized in that the laser ablation by irradiation of laser pulses having a pulse duration shorter than 1 ns (nanosecond) takes place. A method for producing a nib according to claim 19, characterized in that by means of a plurality of laser pulses, an ablation is performed such that the depth and / or width of the groove to be taken out are made variable in place.

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