CH707017B1 - Writing instrument. - Google Patents

Abstract

The invention relates to a writing instrument (1) comprising a body (2) extending longitudinally along a central axis (C); an elastic element (10) fixed to at least a part of the body; characterized in that the elastic element (10) and said at least part of the body (2) are made of material and are made of an at least partially amorphous metal alloy, said elastic element being for example a clip or a spring.

Description

Writing instrument

The present invention relates to a writing instrument comprising a body extending longitudinally along a central axis and a clip extending substantially parallel to the central axis attached to at least a part of the body to a free end .

Technological background

It is known in the prior art writing instruments consisting of a writing instrument comprising a body which extends longitudinally along a central axis C between a front end and a rear end. The front end has an opening through which a writing tip, not visible since retracted, can exit. At the rear end, the writing instrument has a push button which can actuate a mechanism, not shown, for removing / retracting the tip. The body can be produced by two parts, a conical nose and a barrel to which the conical nose is fixed.

This writing instrument is also provided with a clip used so that the user can hang the writing instrument on a shirt pocket for example. This clip consists of an arm provided at one end with a free protuberance to be in contact with the body of the writing instrument and, at a second end, means of attachment for fixing said clip to the body of the writing instrument. These attachment means can be a clip system, that is to say that the clip system is inserted into an opening in the body to fix said clip. The attachment means can also be in the form of an unclosed ring encircling the body of the writing instrument.

A first drawback is that this type of writing instrument is unattractive and fragile. Indeed, the fact that the staple is an attached part entails risks of tearing off said staple during handling.

In addition, a drawback of this configuration is that it requires a manufacturing process in which the body and the clip are each made on their side. An additional assembly step is then planned to equip each writing instrument with a staple.

Furthermore, the material in which the clip is made is any metal. Each material is characterized by its Young E modulus also called elastic modulus (generally expressed in GPa), characterizing its resistance to deformation. In addition, each material is also characterized by its elastic limit σe (generally expressed in GPa) which represents the stress beyond which the material plastically deforms. Thus, it is possible, for a given thickness, to compare the materials by establishing for each the ratio of their elastic limit to their Young's modulus σe / E, said ratio being representative of the elastic deformation of each material. Thus the higher this ratio, the higher the elastic deformation of the material. However, the crystalline materials as used in the prior art, for example, the Cu-Be alloy, whose Young's modulus E is equal to 130 GPa and having an elastic limit σ typically equal to 1 GPa, gives a low σe / E ratio, that is to say of the order of 0.007. These crystal alloy parts therefore have limited elastic deformation. In the case of a clip for a writing instrument, it can be seen that the user tends to handle this clip frequently and the latter ends up being deformed or even broken.

Similarly, the use of crystalline precious metals for the manufacture of such a staple is not possible given the insufficient mechanical characteristics of these metals. Indeed, these precious metals have in particular a low elastic limit, of the order of 0.5 GPa for the alloys of Au, Pt, Pd and Ag, against approximately 1 GPa for the crystalline alloys conventionally used. Given the elastic modulus of these precious metals, which is around 120 GPa, we arrive at a ratio a σe / E of about 0.004. However, a high σe / E ratio is necessary for the production of such a clip as explained above. Consequently, the skilled person is not encouraged to use these precious metals for the production of such a clip.

Another disadvantage of existing writing instruments is the spring placed in the lower part of the body and which provides the restoring force to exit / retract the writing tip. Indeed, this spring is a unique piece that sometimes escapes from the body of the writing instrument when replacing the writing tip, which removes a basic function of the writing instrument.

Summary of the invention

The invention relates to a writing instrument which overcomes the aforementioned drawbacks of the prior art by providing a writing instrument made in one piece from at least partially amorphous material.

To this end, the invention relates to a writing instrument comprising - a body extending longitudinally along a central axis (C); - an elastic element, such as a clip or a spring, fixed to at least one part of the body; characterized in that the elastic element and said at least part of the body are made of material and are made of an at least partially amorphous metal alloy.

Advantageous embodiments of this writing instrument are the subject of dependent claims.

In a first advantageous embodiment, the metal alloy comprises at least one element which is of the precious type, included in the list comprising gold, platinum, palladium, rhenium, ruthenium, rhodium, silver, iridium or osmium.

In a second advantageous embodiment, the clip and said at least one part of the body are made of completely amorphous material.

In a third advantageous embodiment, said material is free of Cobalt, Beryllium or Nickel.

In another advantageous embodiment, said elastic element is a staple extending substantially parallel to the central axis from a first end fixed to at least one part of the body to a free end.

In another advantageous embodiment, said elastic element is a spring comprising at least one element extending substantially radially towards the central axis inside said at least one part of the body.

In another advantageous embodiment, said body comprises at one front end an opening through which a writing tip can come out.

In another advantageous embodiment, said body comprises at a front end a conical nose fixed to said body and comprising an opening through which a writing tip can exit.

In another advantageous embodiment, said body further comprises complementary members directly embedded in said body during a casting or hot forming operation.

The invention also relates to a method for producing a writing instrument according to one of the preceding claims, characterized in that the body is produced by the following steps: a) bring the material of the body; b) making said body by casting said material in a mold; c) cooling the whole so as to give said body an amorphous structure; and d) recovering said body.

Another method of producing a writing instrument is characterized in that the body is produced by the following steps: a) making a preform with said at least partially amorphous material; b) heating the matrices between the glass transition temperature Tg and the crystallization temperature Tx of said material; c) placing the preform between the dies; and d) exert pressure on the preform using the dies for a predetermined time in order to replicate their shape on each of the faces of the preform; e) cooling said body so as to maintain the at least partially amorphous state.

Advantageously, the dies or the mold include surface states so as to replicate them directly during the casting or hot forming operation.

Surprisingly, the precious metals in amorphous form have a high σe / E ratio allowing the production of parts such as the clip or the spring according to the present invention.

A first advantage of the present invention is that it has more interesting elastic characteristics. Indeed, in the case of an amorphous material, the ratio σe / E is increased by raising the elastic limit σe. Thus, the material therefore sees the stress, beyond which it does not resume its initial shape, increase. This improvement in the σe / E ratio then allows greater deformation. This makes it possible to optimize the dimensions of the staple according to whether one wishes to increase the measurement range of the staple or then reduce the size of said staple for an equivalent measurement range. Similarly for the spring, the restoring force can be adjusted by modifying the dimensions of said spring.

Another advantage of these amorphous materials is that they open up new shaping perspectives allowing the production of parts with complicated shapes with greater precision. Indeed, amorphous metals have the particular characteristic of softening while remaining amorphous in a temperature interval [Tx – Tg] given specific to each alloy (with Tx: crystallization temperature and Tg: glass transition temperature). It is thus possible to shape them under a relatively low stress and at a low temperature. This then makes it possible to very precisely reproduce fine geometries, because the viscosity of the alloy decreases sharply and the latter thus marries all the details of the mold.

The present invention also relates to a protective element of a writing tip of an instrument comprising a cap extending longitudinally along a central axis and arranged to fit on the body of said instrument, and a clip s 'extending substantially parallel to the central axis from a first end fixed to the cap to a free end characterized in that the staple and said cap are made of material and are made of metal alloy at least partially amorphous.

In a first advantageous embodiment, the metal alloy comprises at least one element which is of the precious type, included in the list comprising gold, platinum, palladium, rhenium, ruthenium, rhodium, silver, iridium or osmium.

In a second advantageous embodiment, said clip and said cap are made of completely amorphous material.

In a third advantageous embodiment, said material is free of Cobalt, Beryllium or Nickel.

In another advantageous embodiment, said cap further comprises complementary members directly encrusted to said body during a casting or hot forming operation.

The invention also relates to a method for producing a writing instrument which is characterized in that the cap is produced by the following steps: a) bring the constituent material of the cap; b) making said cap by casting said material into a mold; c) cooling the assembly so as to give said cap an amorphous structure; and d) recovering said cap.

The process for producing a writing instrument is also characterized in that the cap is produced by the following steps: a) making a preform with said at least partially amorphous material; b) heating the matrices between the glass transition temperature Tg and the crystallization temperature Tx of said material; c) placing the preform between the dies; and d) exert pressure on the preform using the dies for a predetermined time in order to replicate their shape on each of the faces of the preform; e) cooling said cap so as to keep the state at least partially amorphous.

Advantageously, the dies or the mold include surface states so as to replicate them directly during the casting or hot forming operation.

Brief description of the figures

The aims, advantages and characteristics of the writing instrument according to the present invention will appear more clearly in the following detailed description of at least one embodiment of the invention given solely by way of non-limiting example and illustrated by the attached drawings in which: <tb> fig. 1 <SEP> schematically represents a view in longitudinal section of a writing instrument according to a first embodiment of the present invention; <tb> fig. 2 <SEP> schematically represents a side view of a writing instrument according to the present invention; and <tb> fig. 2A <SEP> schematically represents a view in radial section of a writing instrument according to the present invention; and <tb> fig. 3 <SEP> schematically represents a side view of a writing instrument according to a second embodiment of the present invention.

detailed description

Figs. 1 and 2 show a sectional view of a writing instrument 1 according to a first embodiment. This writing instrument 1 comprises a body 2 which extends longitudinally along a central axis C between a front end 3 and a rear end 4. The front end has an opening 5 through which a writing tip 6, not visible since retracted, can go out. This writing point 6 can be a pencil point or a pen or ball point or a felt placed at the end of a refill (not shown) extending longitudinally in the body 2. At the rear end 4, the writing instrument has a push button 7 which can actuate a mechanism, not shown, for output / retraction of the tip.

This writing instrument is also provided with an elastic element 10 such as a clip 8 used so that the user can hang the writing instrument for example on a shirt pocket. This clip 8 consists of an arm 81 provided at a first end 82 with a protuberance 83 to be in contact with the body of the writing instrument. This clip is fixed, by a second end 84, to the body 2 of the writing instrument.

In a variant, the body 2 can be produced by two parts, a conical nose 9 and a barrel to which the conical nose is fixed. It can also be produced in three parts, a first part at which the clip is fixed, a second part used for gripping said instrument and a third part which is the conical nose fixed to the second part. These three parts thus form said body 2.

Advantageously according to the invention, at least the first part of the body 2 and the clip 8 come from one material and are made of a completely amorphous or partially amorphous material. In particular, metallic glasses are used, that is to say amorphous metallic alloys. This configuration of having at least the first part of the body 2 and the one-piece clip 8 offers a more solid and better appearance.

Indeed, the advantage, in terms of deformation of these amorphous metal alloys, comes from the fact that during their manufacture, the atoms making up this amorphous material do not arrange themselves according to a particular structure as is the case for crystalline materials. So even if the Young's modulus E of a crystalline material and an amorphous material is identical, the elastic limit, σe, is different. Indeed, the amorphous material is differentiated by an elastic limit σea higher than that of the crystalline material with a ratio substantially equal to two. This allows amorphous materials to be able to undergo a greater stress before arriving at the elastic limit σe, the stress thus supported being four to eight times greater than that supported by an equivalent crystalline material.

First, this configuration improves the reliability of clip 8 on the writing instrument. Indeed, the elastic limit σea is higher, which makes the plastic region more distant and therefore reduces the risk of plastically deforming the clip 8 when the user manipulates the writing instrument.

In addition, advantageously, it is found that a clip 8 of amorphous material also allows for the same constraint, the optimization of its dimensioning in order to withstand the same constraints. Indeed, the dimensions of the clip 8, such as the thickness modify its deformation. Advantageously, with an elastic limit which increases, the stress which can be applied to the clip 8, without plastic deformation, increases. It then becomes possible to keep the same resistance to stress by reducing its thickness. The clip 8 therefore becomes thinner and therefore less visible, which can bring more in terms of aesthetics.

Furthermore, amorphous materials or amorphous metal alloys have the characteristic of being harder than their crystalline equivalents. Therefore, the body 2 made of such materials will be harder and therefore more resistant.

We can then cite as examples of amorphous materials that can be used: Zr41Ti14Cu12Ni10Be23 whose Young's modulus E is 105 GPa and the elastic limit is σe = 1.9 GPa, and which has a ratio σe / E = 0.018 and the Pt57.5Cu14.7Ni5.3P22.3 whose Young's modulus E is 98 GPa and the elastic limit is σe = 1.4 GPa with a ratio σe / E = 0.014. It will be understood that the alloys cited in the following patents: US 5,288,344; US 5,618,359 and US 7,368,022 are incorporated by reference in said application.

Of course, there are other characteristics which may be of interest, such as the allergenic aspect of the alloy. Indeed, it can be noted that the materials, whether crystalline or amorphous, often use alloys comprising allergenic elements. For example, such types of alloys include Cobalt, Beryllium or Nickel. Thus, variants of the invention can be made with alloys which do not contain these allergenic elements. We can also predict that allergenic elements are present, but that these do not cause an allergenic reaction.

According to another variant of the invention, it can be provided that the at least first part of the body 2 and the clip 8 are made of noble material. Indeed, in the crystalline state, the noble materials such as gold or platinum are too soft to allow the realization of a flexible and robust clip 8. But as soon as they are in the form of metallic glass, that is to say in the amorphous state, these precious metals are then endowed with characteristics such that their use becomes possible while offering a precious and aesthetic appearance . Preferably, platinum 850 (Pt 850) and gold 750 (Au 750) are the precious metals which will be used for the production of the assembly formed by said at least first part of the body 2 and the clip 8. Of course, other precious metals can be used such as palladium, rhenium, ruthenium, rhodium, silver, iridium and osmium. It will be understood that the alloys cited in the following patents: WO 2006/045 106 and WO 2004/059 019 are incorporated by reference into said application.

It can also be seen that the amorphous metal alloys have an ease of shaping. Indeed, amorphous metals have the particular characteristic of softening while remaining amorphous in a given temperature interval (Tx – Tg) specific to each alloy. It is thus possible to shape them under a relatively low stress and at a temperature not too high.

This process, described precisely in US patent 2003/0 047 248 incorporated by reference in the present application, consists of hot forming of an amorphous preform. This preform is obtained by melting the metallic elements constituting the amorphous alloy in an oven. This fusion is carried out under control with the aim of obtaining the lowest possible contamination of the oxygen alloy. Once these elements are melted, they are poured in the form of a semi-finished product, then cooled quickly to keep the amorphous state. Once the preform has been completed, hot forming is carried out in order to obtain a final part. This hot forming is carried out by pressing in a temperature range between Tg and Tx for a determined time to maintain a totally or partially amorphous structure. This is done in order to preserve the elastic properties characteristic of amorphous metals. The different stages of final shaping are then: <tb> i. <SEP> heating of the dies having the negative form of the assembly formed by the at least first part of the body 2 and the clip 8 to a chosen temperature, <tb> ii. <SEP> introduction of the amorphous metal preform between the hot matrices, <tb> iii. <SEP> application of a closing force on the dies in order to replicate the geometry of the latter on the amorphous metal preform, <tb> iv. <SEP> waiting for a selected maximum time, <tb> V. <SEP> opening of the matrices, <tb> vi. <SEP> rapid cooling of the assembly formed by the at least first part of the body 2 and of the clip 8 below Tg, and <tb> vii. <SEP> leaving the assembly formed by the at least first part of the body 2 and the clip 8 of the dies.

This form of shaping makes it possible to very precisely reproduce fine geometries, because the viscosity of the alloy decreases sharply, the latter thus marrying all the details of the mold. The advantage of this method is that there is no solidification shrinkage, which makes it possible to have a more precise part, produced at a lower temperature than by injection. In addition, this makes it possible to produce at least a first part of the body 2 and the clip in one and the same step. In addition, the fact of having at least the first part of the body 2 and the clip 8 made of material makes it possible to reduce the risks of tearing.

Of course, other types of shaping are possible such as shaping by injection. This process, described precisely in US Pat. No. 5,711,363 incorporated by reference in the present application, consists in molding the alloy obtained by melting the metallic elements in an oven, in the form of any part such as a rod and that in a crystalline or amorphous state, whatever. Then this piece of any shape in alloy is again melted to be injected into a mold having the shape of the final piece. Once the mold is filled, it is quickly cooled to a temperature below Tg in order to avoid crystallization of the alloy and thus obtain the assembly formed of the at least first part of the body 2 and of the clip 8 in amorphous or semi-amorphous metal.

Thus, it is therefore possible to form the assembly formed of the at least first part of the body 2 and the clip 8 according to the desired geometry.

A variant consists in making decorations directly during the manufacture of the assembly formed by the at least first part of the body 2 and the clip 8. For this, the decorations of the writing instrument 1 such that of the Geneva coast type, beading, satin-finishing or guilloche work are carried out directly in the negative impressions of said mold or of said dies used for, respectively, casting and hot forming. Thus, in addition to the advantages mentioned above, this variant also makes it possible to dispense with the heavy tooling currently used to produce these decorations in series. It is understood that the method therefore allows the production of a decorated writing instrument more quickly and, incidentally, less expensive.

Advantageously, provision can be made for complementary bodies such as pearly inserts or precious stones to be encrusted in the writing instrument. Provision may be made for this complementary member to be placed directly in the mold or on the dies and encrusted during the steps of casting or hot forming. This complementary organ is thus an integral part of the writing instrument and is not an attached part.

In a second embodiment visible in FIG. 3, the writing instrument 1 comprises a protective element or cap 20 intended to be fixed on the body 2 and to protect the front end 3. In fact, the writing tip 6 is arranged at this end before 3 and it is sometimes necessary to protect this writing tip, especially in the case of a pen or felt tip. This cap 20 comprises a component extending longitudinally along the central axis C. This component is arranged to fit onto the body 2 of said instrument. It is conceivable that said protective element comprises a clip 80. This clip 80 extends substantially parallel to the central axis (C) from a first end fixed to the component to a free end.

Advantageously, the clip 80 and said cap 20 are made of material and are made of at least partially amorphous metal alloy. Of course, the variants described for the first embodiment are also possible for this second embodiment.

In the case of a writing instrument with push-button and retractable lead or ball, it will also be noted that the body 2 can also comprise a return spring 11 of the writing-charging tip assembly as is visible in fig. 2 and 2A. Advantageously, this spring comes integrally with the body 2 and can take the form of an openwork washer extending radially in the direction of the center of the body 2 guaranteeing the spring effect. Alternatively, this washer can be replaced by a plurality of tongues extending radially in the direction of the center of the body 2. A slight inclination may be present to ensure better operation. The use of amorphous metal alloy makes it possible to obtain a spring supporting a higher stress guaranteeing a higher reliability. This return spring 11 can also be produced directly with the body 2 during a hot forming or casting operation.

It will be understood that various modifications and / or improvements and / or combinations obvious to those skilled in the art can be made to the various embodiments of the invention described above without departing from the scope of the invention defined by the appended claims.

Claims (20)

1. Writing instrument (1) including - a body (2) extending longitudinally along a central axis (C); - an elastic element (10), such as a clip or a spring, fixed to at least one part of the body; characterized in that the elastic element (10) and said at least part of the body (2) are made of material and are made of an at least partially amorphous metal alloy. 2. Writing instrument according to claim 1, characterized in that the metal alloy comprises at least one element which is of the precious type, included in the list comprising gold, platinum, palladium, rhenium, ruthenium , rhodium, silver, iridium or osmium. 3. Writing instrument according to claim 1, characterized in that said elastic element and said at least one part of the body are made of completely amorphous metal alloy. 4. Writing instrument according to one of the preceding claims, characterized in that said metal alloy is free of Cobalt, Beryllium or Nickel. 5. Writing instrument according to one of the preceding claims, characterized in that said elastic element is a staple (8) extending substantially parallel to the central axis (C) from a first end fixed to at least one part from the body to a free end. 6. Writing instrument according to one of claims 1 to 4, characterized in that said elastic element (10) is a spring (11) comprising at least one element extending substantially radially towards the central axis (C) inside said at least part of the body (2). 7. Writing instrument according to one of the preceding claims, characterized in that said body comprises at one front end an opening through which a writing tip can come out. 8. Writing instrument according to one of claims 1 to 6, characterized in that said body comprises at a front end a conical nose fixed to said body and comprising an opening through which a writing tip can come out. 9. Writing instrument according to one of the preceding claims, characterized in that said body also comprises complementary members directly encrusted to said body during a casting or hot forming operation. 10. Method for producing a writing instrument according to one of the preceding claims, characterized in that the body (2) is produced by the following steps: a) provide the metal alloy constituting the body (2); b) making said body by casting said material in a mold; c) cooling the whole so as to give said body an amorphous structure; and d) recovering said body. 11. A method of producing a writing instrument according to one of claims 1 to 9, characterized in that the body (2) is produced by the following steps: a) making a preform with said at least partially amorphous metal alloy; b) heating the matrices between the glass transition temperature Tg and the crystallization temperature Tx of said material; c) placing the preform between the dies; and d) exert pressure on the preform using the dies for a predetermined time in order to replicate their shape on each of the faces of the preform, e) cooling said body (2) so as to maintain the at least partially amorphous state. 12. Method according to claims 10 or 11, characterized in that the dies or the mold include surface states so as to replicate them directly on said body during the casting or hot forming operation. 13. Protective element for a writing tip of an instrument comprising a cap (20) extending longitudinally along a central axis and arranged to fit onto the body of said instrument, and a clip (80) s' extending substantially parallel to the central axis (C) from a first end fixed to the cap to a free end characterized in that the clip and said cap are made of material and are made of at least partially amorphous metal alloy. 14. Protective element according to claim 13, characterized in that the metallic alloy comprises at least one element which is of the precious type, included in the list comprising gold, platinum, palladium, rhenium, ruthenium, rhodium, silver, iridium or osmium. 15. Protective element according to claim 13, characterized in that said clip (80) and said cap (20) are made of completely amorphous metal alloy. 16. Protective element according to one of claims 13 to 15, characterized in that said metal alloy is free from Cobalt, Beryllium or Nickel. 17. Protective element according to claims 13 to 15, characterized in that said cap (20) further comprises complementary members directly encrusted to said body during a casting or hot forming operation. 18. Method for producing a protective element according to one of claims 13 to 17, characterized in that the cap (20) is produced by the following steps: a) provide the metal alloy constituting the cap (20); b) making said cap (20) by casting said material in a mold; c) cooling the assembly so as to give said cap (20) an amorphous structure; and d) recovering said cap (20). 19. Method for producing a protective element according to one of claims 13 to 17, characterized in that the cap (20) is produced by the following steps: a) making a preform with said at least partially amorphous metal alloy; b) heating the matrices between the glass transition temperature Tg and the crystallization temperature Tx of said material; c) placing the preform between the dies; and d) exert pressure on the preform using the dies for a predetermined time in order to replicate their shape on each of the faces of the preform, e) cooling said cap (20) so as to preserve the at least partially amorphous state. 20. Method according to claims 18 or 19, characterized in that the dies or the mold include surface states so as to replicate them directly on said cap during the casting or hot forming operation.