Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
  • F03G—SPRING, WEIGHT, INERTIA OR LIKE MOTORS; MECHANICAL-POWER PRODUCING DEVICES OR MECHANISMS, NOT OTHERWISE PROVIDED FOR OR USING ENERGY SOURCES NOT OTHERWISE PROVIDED FOR
  • F03G7/00—Mechanical-power-producing mechanisms, not otherwise provided for or using energy sources not otherwise provided for
  • F03G7/06—Mechanical-power-producing mechanisms, not otherwise provided for or using energy sources not otherwise provided for using expansion or contraction of bodies due to heating, cooling, moistening, drying or the like
• • D—TEXTILES; PAPER
  • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
  • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
  • D02G3/00—Yarns or threads, e.g. fancy yarns; Processes or apparatus for the production thereof, not otherwise provided for
• • D—TEXTILES; PAPER
  • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
  • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
  • D02G3/00—Yarns or threads, e.g. fancy yarns; Processes or apparatus for the production thereof, not otherwise provided for
  • D02G3/02—Yarns or threads characterised by the material or by the materials from which they are made
  • D02G3/04—Blended or other yarns or threads containing components made from different materials
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M23/00—Treatment of fibres, threads, yarns, fabrics or fibrous goods made from such materials, characterised by the process
  • D06M23/14—Processes for the fixation or treatment of textile materials in three-dimensional forms
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M23/00—Treatment of fibres, threads, yarns, fabrics or fibrous goods made from such materials, characterised by the process
  • D06M23/16—Processes for the non-uniform application of treating agents, e.g. one-sided treatment; Differential treatment

Definitions

• the present invention relates to a method and a device for its implementation, for modifying at least one characteristic of a wire element, and in particular the distance separating its two ends, and provided with a winding means of said wire element.
• Kevlar® offers a very interesting breaking strength. This thermoplastic polymer has a breaking strength of the order of 3100 MPa. However it is very little elastic or extensible and breaks quite easily in case of compression or when it is flamed.
• a material such as rubber is more or less elastic.
• an elastomer withstands up to 200% extensibility before breaking. By cons, this type of material is not very resistant in case of shock.
• a biomaterial such as spider capture silk can in turn group together several particular properties such as adaptability, extensibility or resistance to breakage. However, it is very difficult to produce, which makes the use of this type of material almost non-existent.
• the invention therefore aims to respond to the problems set out above by proposing a device and a method for producing an easily industrializable device that combines several particular properties.
• the device comprising a wire element and a winding element thereof and associated with said wire element, is characterized in that the winding means is adapted to pass from a first stable state to a second stable state, this change of state occurring either naturally, so that the interaction energy between the wire element and the environment is higher than the interaction energy between the wire element and the winding means,
• a steady state is defined as a state to which the system naturally returns if disturbed by an external event.
• a stable state is one where the system has the lowest energy.
• naturally and “chemical affinity” means that the interaction energy between the wired element and the environment is higher than the interaction energy between the wired element and the winding means. . These favorable interactions may be due to molecular resemblances (carbon / silica chains, hydrogen bonding, etc.) so that the energy of the wired element and the winding means taken separately is greater than the energy of the the wire element and the winding means in interaction.
• the invention by the combination of a wire element and a winding means, each having their own function, creates a new function.
• the winding means is a liquid droplet.
• the invention makes it possible to produce a hybrid mechanical assembly between liquid and solid, and thus to obtain an adaptable material under compression, and which has a high tensile rigidity.
• the interaction energy between the wire element and the environment is 4.4 J / m 2
• the interaction energy between the wire element and the winding means is 4.33 J / m 2 .
• the invention also provides a method of changing at least one mechanical property such as the curvature stiffness of a wire element, characterized in that at least one body of fluid material (liquid, gas) is associated with it. or solid, and in that one changes at least one characteristic of the material of said body.
• at least one mechanical property such as the curvature stiffness of a wire element
• the modification may relate to a parameter such as the ambient air pressure, the temperature, the intensity or the direction of the electric field, the intensity or the direction of the magnetic field, to buckle the wire element thanks to a mechanical stress, or any other parameter able to influence the system, so as to cause winding of the wire element in or around said body.
• a capillary winch phenomenon By capillary winch is meant the phenomenon consisting of a winding of the wire element, in the winding means, which may be a body of fluid or solid material.
• a mechanical stress represents the ratio between the force applied to an object and the section of the object taken perpendicular to the direction of the force.
• the notion of mechanical stress is used to represent the influence of an external force on an object regardless of its size.
• the wire element and the winding means may have affinities defined for example by
• the wired element has a sufficiently fine diameter to be able to wind
• End means a wire having a radius less than 3 times the radius given by the equation
• Characteristics Wired element and winding means The size of the wire element with respect to the winding means is a
• the wire element may for example have a diameter
• winding means is a drop of liquid.
• the aim of the invention is to obtain a fiber of radius inferior to that defined by
• a fiber is currently considered fine if its radius is less than three times that given by said equation.
• the material constituting the winding means may be tin, wax, silicone, water or any liquid wetting the wire element, in the case where the medium winding is a drop of liquid.
• the wire element may consist of metals, elastomers or polymers such as polyurethane, synthetic rubber, nylon fibers, Kevlar fibers, carbon fibers, deformable steel, glass fibers, elastic plastic material (partly preserving the deformations that it has been imposed), a highly deformable material, or any material that can be obtained in fine fiber, and advantageously in fibers with a diameter of less than 10 microns.
• the winding means is a drop of liquid.
• the drop of liquid constituting the winding means will have to be compatible with the wire element.
• the drop must wet the wire element and must extend as far as possible over the wire element.
• the effective contact angle between the wire element and the droplet is then less than 90 ° .
• the drop may already be in the liquid state or may be obtained from a solid material, converted into a liquid state, and especially by heating.
• the environment parameter is the temperature.
• the temperature corresponding to the first stable state of the winding means may be the ambient temperature, for example 20 ° C.
• the temperature in the second stable state, allowing the winding of the wire element may be between the melting temperature and the boiling temperature of the liquid used.
• several liquid drops or several wire elements may be associated to multiply the effects of the invention.
• the so-called environment parameter is the electric field.
• at least one characteristic of the winding means contact angle, capillary compression force
• of the wire element thickness in the case of electroactive polymers for example
• Said parameter is in one example, the temperature (according to a particular form, the temperature in the second modified state, causing winding of the wire element, being between 30 and 80 ° C, and preferably between 50 and 70 ° VS ) ;
• Said body is a drop of wetting liquid or a partial wetting liquid whose contact angle is less than 90 °.
• the material constituting the winding means has one and / or the other of the following characteristics: a glass transition temperature of between 30 ° C. and 80 ° C., and preferably between 45 ° and 65 ° C .;
• the wire element has a diameter less than or equal to one centimeter, preferably between 0.5 micron and 1 cm, preferably between 1 micron and 100 microns, even more preferably between 1 micron and 10 microns; and or
• E Young's modulus
• r radius
• - is made of polyurethane, synthetic rubber, nylon fiber, kevlar fiber (R), carbon fiber, high elasticity steel, elastic plastic material, super elastic material.
• the dimension ratio between the diameter of the wire element and the diameter of the block or drop is between 0.0125 and 0.05.
• the so-called “high elasticity” or “super-elastic” materials are materials that can deform strongly before reaching their point. a break. For example, the glass is deformed by 0.5% before breaking. Super-elastic materials are much more deformable, at least 5% (before rupture).
• the diameter of the drop is between 1 micron and 1 cm.
• the diameter of the winding means is less than 3 mm.
• the diameter of the winding means is between 20 and 80 times the radius of the wire element, and preferably between 45 and 55 times the radius.
• the invention also relates to the application of the above device to constitute a motor, an activator, an actuator, an artificial muscle, a means for moving an object relative to another object (the objects being connected to the two respective ends of said object). wired element), a set of electrical or electronic junctions of variable length, explained later in the description.
• the invention relates to a method for providing the liquid drop protection means against external aggression, mechanical or otherwise.
• the drop is encapsulated in an envelope formed of a multitude of solid grains, and less than 50 times in size, preferably 100 times smaller than the latter, the grains covering the outer surface of the drop. , at least most, and preferably all, of the surface thereof.
• the grains are formed of colloids, of micrometric size, and are for example glass, polystyrene or any other material comprising the required properties of wetting, that is to say that the interaction energy between the grains and the drop must be of the same order of magnitude as the interaction energy between the grains and the external medium.
• FIG. 1 shows a top view of a drop of liquid and a thread of polyurethane, wound inside it.
• Figure 2 shows the variation curve of the elongation of a spider capture wire as a function of the pulling force
• Figure 3 shows the tensile curve of a polyurethane yarn with drop (dotted line curve) and without (solid line curve) drop.
• Figs. 4A and 4B are photos showing a drop and the associated wire, respectively at room temperature and at 75 ° C.
• FIGS. 5A and 5B are perspective diagrams of another example of implementation of the method of the invention.
• Figure 6 shows the particular application of the device to create a spring.
• Figure 7 shows a schematic front view of a drop provided on its surface with encapsulation grains, and placed in a liquid
• Figure 8 shows a photograph of a drop of a drop covered with encapsulation grains.
• the fiber used in the invention can to be super elastic.
• Superelasticity is a term used in the field of shape memory alloys (AMF, or shape memory alloy, SMA, in English). If such an alloy is subjected to tension, it stretches strongly, then when the tension is released, it retracts to its original length (no residual deformation). The particular mechanical behavior of AMFs is due to a phase change in the microstructure of the material.
• Figure 1 is a representation of a particular embodiment of the invention wherein the drops are able to fold and wind the wire within themselves.
• the drops arranged on the wire locally compress the latter by capillary contraction.
• This capillary compression comes from the fact that the drop tends to adopt a spherical shape, which minimizes its surface with its environment. If this compression is strong enough, the fiber present in the drop can bend, or even curl in the drop, thus achieving a "capillary winch".
• the tensile curve of a spider silk thread considered the most interesting biological material to reproduce is given in Figure 2. This curve shows that the wire can be strongly stretched. This great extensibility comes from the reserve of thread present in the drops, thanks to the capillary winding.
• the rigidity extension is adaptable: small deformations, the rigidity is almost zero, the wire is just unfolding. At large deformations, the yarn begins to be really stretched, and has a stiffness comparable to a material such as Nylon®. This tensile curve resembles that of a material like collagen. This is particularly interesting in the case of biological applications, where one seeks an adaptable material with a mechanical response evolving with the deformation.
• the present invention implements this phenomenon with, for example, synthetic fibers, provided that the fiber is sufficiently small to be pliable, and that the liquid constituting the drop is sufficiently wetting. This phenomenon is thus reproducible with a wide range of materials and liquids.
• the wire element is composed of soft polyurethane yarns, a common commercial polymer and inexpensive.
• the polyurethane is melted, extruded at high speed to form a micron sized fiber.
• a drop of silicone oil On this fiber is deposited a drop of silicone oil and the phenomenon of capillary winch is automatically manifested, see Figure 1.
• a yarn, associated with drops of silicone oil, is then obtained which can be stretched to more than twenty times its initial length with a constant force.
• this thread is automatically stretched regardless of the extension; there is no gravity deflection.
• the retention under compression means that it remains tense when approaching its ends.
• the drops give it a great damping power (shock absorption, vibration damping, etc.).
• Figure 3 shows that the polyurethane yarn associated with drops reproduces qualitatively the mechanical properties of the capture silk (compression retension, adaptable rigidity and excellent damping).
• the wire / drop assembly has a typical mechanical response of a biological material, although being completely artificial.
• Figure 3 shows the tensile curve of a polyurethane yarn with (dotted line curve) and without (solid line curve) drop.
• the solid line curve shows the intrinsic mechanical properties of the polyurethane yarn, similar to that of a conventional rubber band elastomer.
• the dotted line curve shows the high extensibility (multiplied by a factor of 4) of the wire when decorated with drops, as well as the adaptable rigidity.
• PLA polyacid lactic acid
• Young's modulus The stiffness of a wire's curvature depends on its thickness and its natural elastic stiffness in extension (Young's modulus). The Young's modulus is modified to be able to trigger the winch mechanism at will.
• a PLA wire is used whose Young's modulus is of the order of Giga Pascal (GPa), and 1 to 3 microns in diameter. Such a wire, once associated with drops of silicone oil, does not undergo a winch mechanism because it is too rigid.
• critical glass transition temperature of this polymer - glass transition means the transition between a glassy state such as glass (rigid and brittle) and a rubbery state (soft and extensible))
• the thread sees its stiffness divided by a factor of 1000 and the phenomenon of winch is then manifested directly.
• Returning to the critical temperature will "freeze” the winding (see “Applications Considered” section below). It is therefore possible to use the temperature as a control or switch so as to control the winch phenomenon.
• the use of molten tin drops (whose melting temperature is around 200 ° C.) could make it possible to thermally activate the phenomenon or to freeze the winding.
• the device of the invention is simple to implement to provide classic materials of extreme mechanical properties such as super extensibility, adaptability of length (smart meta-materials), excellent damping, and perfect perfect reversibility (no plasticity or fatigue). Another embodiment of the device is described with reference to FIGS. 5A and 5B.
• drops of tin are used to move (by translation) microsystems.
• Two blocks or objects belonging to a microsystem must be brought together ( Figure 5A). They are connected by metal son, these son being associated according to the invention to small pieces of solid tin. Tin is liquefied (by laser, or by Joule effect - heating of the wire when traversed by an electric current). The winch mechanism described above is activated and the blocks are brought closer to each other. Once the translation has been carried out, the tin may be re-solidified and the system thus locked in the "close" position.
• the coupling between the fiber and the drop it carries can have an avalanche effect and completely change the overall mechanical properties. It is therefore possible to switch from a conventional material to a material having exceptional properties, adaptable under the effect of external stimuli, even low: the temperature affects the rigidity of the fiber, an electric field influences the effect of capillary winch of the drop, as well as surfactants that can respond to many external stimuli such as light activation, thermal or electrical.
• the mechanical properties durable such as in the non-limiting example of the solidified tin drop.
• the great freedom of the parameters involved sizes of the drop and the fiber, rigidity of the fiber and the liquid constituting the drop
• the materials thus created can find application in the following areas:
• the wire / winding means assembly can be used as a motor. Indeed, by winding the wire through the winch effect, the drop applies a driving force on the wire, which can then be applied to an external system.
• This could also be used as an actuator or motor that can be turned on or off at will (reversible phenomenon).
• a very interesting aspect of this motor / actuator is that no material is physically stretched during the low strain elongation, which makes it possible to have a perfect reversibility of the engine, and therefore a much longer lifetime than with classical materials that include plasticity.
• This invention also makes it possible to limit fatigue, phenomena limiting performance and ultimately causing rupture
• the actuator system can be used to create a local winding of permanent wire, when the drop is removed: if one place a drop on a rigid fiber, then increase its temperature, then the wire wraps in the drop, and when the temperature decreases, the winding is "frozen".
• a 3D object with a complex geometry is thus created in a simple way (see Figure 6).
• changing an environment parameter is not a necessity.
• the winding can be done naturally by the affinity of the wire element and the winding means, however, the performance will be reduced.
• wire elements can be associated to include artificial muscle. Indeed, it is sufficient to attach a large number of wired elements / activatable winding means between two surfaces to multiply the effects of the invention and obtain an artificial muscle fiber.
• the invention can be used to create springs or complex three-dimensional objects, such as a micro-coil.
• a winding for example with a drop of liquid (non-limiting case).
• This drop of liquid having an affinity with a wire element will allow the wire element to wind in this drop.
• the user can decide to come and suck the drop, for example using a pipette, or to remove the drop without contact, by blowing or intense electric field pulsed.
• the wire element is therefore found in the "wound” state, and a spring for example can be created.
• the wire element has undergone permanent deformations, either by the procedure described above, in the "microfabrication” paragraph, or by plasticization. ( Figure 6)
• the winding means is a droplet
• This encapsulation can be as physical, by the construction of a non-wetting cage for the drop (non-limiting example), as chemical, by the use of viscoelastic fluids, which have the property of behaving like a solid in case of fast contact, and therefore do not spread.
• the wired element may have the following characteristics:
• Young's modulus of the fiber used 12 +/- 1 MPa.
• the wired element is an Elastollan fiber.
• the known Elastollan sample (without drop) has a stretch extensibility of +530%, whereas the same sample associated with a drop of silicone oil (according to the invention) has an extensibility to break more than 3000%.
• This thread was produced as follows:
• TPU Elastollan 1185A Some granules of TPU Elastollan 1185A are placed on a hot plate covered with aluminum foil, set at 230 ° C. When the TPU melts, a part is pinched and stretched as quickly as possible by the operator, creating several meters of micron fibers. A seemingly homogenous part is selected, and the fiber is wound at one end around the FemtoTools FT-S1000 sensor mounted on a SmarAct SLC-1730 linear positioner and glued with Loctite® or SuperGlue® type glue onto a glass slide. other end.
• Rhodorsil 47V1000 silicone oil hangs from the tip of a 0.4mm diameter syringe, and the fiber is brushed along its length to deposit a large amount of liquid.
• the typical dynamic reaction time of the system is of the order of 100 ms.
• Figure 3 shows the variations of the voltage force as a function of the extension (Strain) of the system.
• the extension is defined as (LL 0 ) / L 0 .
• the mechanical response of the system of the invention the Tension force depending on the extension (Strain) of the system.
• the extension is defined as (LL 0 ) / L 0 where L 0 is the length of the system initially when a lot of fiber is wrapped in the drop (s).
• strain or "strain" 2.5
• the fiber of the invention (associated with a drop) has a large reserve of extensibility.
• the inset shows for comparison the mechanical response of a spider fiber.
• the wire / drop assembly of the invention typically having the same mechanical properties as spider wire, while avoiding the difficulties of spider silk synthesis and the characterization of natural liquid drops, present on the spider's thread.
• Figs. 4A and 4B are photos showing a drop associated with a PLA wire, respectively at room temperature and at 75 ° C.
• the PLA used for these figures has the following characteristics:
• Young's modulus of PLA 5 GPa at room temperature, 70 MPa at 75 ° C.
• Wire radius used 1.7 microns (same technique as for TPU, except that a metal nozzle is used for extrusion instead of a single hot plate).
• Number of turns made 2.5 turns (8 times the size of the drop).
• the invention relates to a method for providing the taste of liquid means of protection against external aggression, mechanical or otherwise.
• Said method encapsulates the drop in an envelope formed of a multitude of grains, each formed of a liquid different from that of the drop, and of size less than 50 times, preferably 100 times smaller than the drop.
• the multitude of grains covers the outer surface of the drop, preferably entirely.
• the grains are formed of colloids, of micrometric size, and are for example glass, polystyrene or any other material comprising the required properties of wetting, that is to say that the interaction energy between the grains and the drop must be of the same order of magnitude as the interaction energy between the grains and the external medium.
• the grains 1 are mixed with a first liquid, for example oil, then a drop 2 formed of the mixture is placed in a second liquid 3, for example water.
• a first liquid for example oil
• Figure 8 is a photograph of a grain-coated drop, according to Figure 7.
• the method of encapsulation by grains is used because it has the advantage of constituting a protection without compromising the liquid nature of the drop. Indeed, unlike a solid shell, grains can move and reorganize on the surface of the drop. Those skilled in the art can refer to the publication: Aussillous, Pascale, and David Quowski. "Liquid marbles.” Nature 41, 6840 (2001): 924-927.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• General Engineering & Computer Science (AREA)
• Materials For Medical Uses (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)

Applications Claiming Priority (2)

Publications (1)

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• 2014
  • 2014-04-30 FR FR1453960A patent/FR3020630B1/fr not_active Expired - Fee Related
• 2015
  • 2015-04-30 EP EP15736532.1A patent/EP3137662A1/de not_active Withdrawn
  • 2015-04-30 JP JP2016565338A patent/JP2017515005A/ja active Pending
  • 2015-04-30 WO PCT/FR2015/051163 patent/WO2015166190A1/fr active Application Filing
  • 2015-04-30 US US15/307,822 patent/US20170067453A1/en not_active Abandoned
  • 2015-04-30 CA CA2947497A patent/CA2947497A1/fr not_active Abandoned

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