WO2019020703A1 - Procédé de fabrication d'un ressort hélicoïdal - Google Patents

Procédé de fabrication d'un ressort hélicoïdal Download PDF

Info

Publication number
WO2019020703A1
WO2019020703A1 PCT/EP2018/070204 EP2018070204W WO2019020703A1 WO 2019020703 A1 WO2019020703 A1 WO 2019020703A1 EP 2018070204 W EP2018070204 W EP 2018070204W WO 2019020703 A1 WO2019020703 A1 WO 2019020703A1
Authority
WO
WIPO (PCT)
Prior art keywords
extruded profile
fibers
longitudinal
layers
mold
Prior art date
Application number
PCT/EP2018/070204
Other languages
German (de)
English (en)
Inventor
Gregor Daun
Jan Wucherpfennig
Christian KORFF
Original Assignee
Basf Se
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Basf Se filed Critical Basf Se
Publication of WO2019020703A1 publication Critical patent/WO2019020703A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/28—Shaping operations therefor
    • B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C53/00—Shaping by bending, folding, twisting, straightening or flattening; Apparatus therefor
    • B29C53/02—Bending or folding
    • B29C53/12—Bending or folding helically, e.g. for making springs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F1/00—Springs
    • F16F1/36—Springs made of rubber or other material having high internal friction, e.g. thermoplastic elastomers
    • F16F1/366—Springs made of rubber or other material having high internal friction, e.g. thermoplastic elastomers made of fibre-reinforced plastics, i.e. characterised by their special construction from such materials
    • F16F1/3665—Wound springs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/06—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts
    • B29K2105/08—Condition, form or state of moulded material or of the material to be shaped containing reinforcements, fillers or inserts of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns
    • B29K2105/10—Cords, strands or rovings, e.g. oriented cords, strands or rovings
    • B29K2105/101—Oriented
    • B29K2105/103—Oriented helically
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/30—Vehicles, e.g. ships or aircraft, or body parts thereof
    • B29L2031/3055—Cars
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/772—Articles characterised by their shape and not otherwise provided for
    • B29L2031/7732—Helical
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
    • B29L2031/00—Other particular articles
    • B29L2031/774—Springs
    • B29L2031/7742—Springs helical springs

Definitions

  • Fiber-reinforced materials contain as essential components fibers as reinforcing material and a matrix system in which the fibers are embedded.
  • the fibers are based on glass, carbon, aramid, polyacrylonitrile, polyester or polyamide.
  • Thermosetting polymers for example polyester resins, vinyl ester resins, polyurethane resins or epoxy resins, or thermoplastic polymers such as polyamides, polypropylenes or polyethylenes are usually used as the matrix system.
  • Various processes are known for the production of fiber-reinforced extruded profiles.
  • the fibers are unwound from bobbins, soaked in the matrix system or otherwise wetted, formed into the desired profile shape and cured.
  • the fibers themselves may form the profile shape or they may be applied to a base body.
  • the process is usually carried out continuously by continuously drawing the workpiece formed by the impregnated fibers through the plant.
  • the fibers are also unrolled from bobbins and impregnated with the matrix system or otherwise wetted.
  • this is a discontinuous process in which a core or body to be coated rotates and the fibers are guided by an axial reciprocation on the workpiece and wound on this until the desired thickness of the fiber-plastic Layer is reached.
  • the so-called Pullwinding vide represents a combination of pultrusion and
  • a strand-shaped workpiece is pulled through the plant, while fiber coils rotate around the workpiece, the fibers are soaked or wetted and the wetted fibers are deposited on the workpiece. In this case, the wetting can also take place only on the workpiece
  • the strand-shaped workpiece may be a preformed body, such as a tube, but it may also be formed by fibers, which are brought in a first stage, for example in the pultrusion in a profile shape.
  • extruded profiles are produced by such methods by wrapping several layers made of the composite around a core.
  • the composite layers are made of fibers embedded in a polymer matrix.
  • the extruded profile produced in this way can optionally be encased.
  • WO 2012/066246 A1 describes a method for producing a from a
  • fiber-reinforced composite produced coil spring, in which an extruded profile in the form of a coil spring on an inflatable inner mold is cured.
  • Disposable molds must be thermosetting and must be prepared, destroyed and disposed of for each coil spring, so that these forms are not suitable for a larger manufacturing scale of coil springs for cost reasons.
  • Many coil springs also deviate from the cylindrical shape in the direction of a banana shape, S shape or barrel shape, which makes the design and manufacture of the inner molds even more complex.
  • a basic idea of the present invention is the use of a suitable fiber arrangement in the composite material of the extruded profile for the production of the coil spring, so that it is possible to dispense with an internal shape for fixing the coil spring during curing, and instead an external shape is sufficient for positioning the coil spring, since these extruded profiles are in the Press the mold outwards into the mold and do not move inward and avoid positioning.
  • An inventive method for producing a coil spring, in particular a coil spring for a chassis of a motor vehicle comprising:
  • an extruded profile is understood to be a workpiece which is formed by unwinding fibers, impregnating the fibers with a matrix material and shaping the fibers into a predetermined profile.
  • the extruded profile is in particular a by a Strangzieh compiler,
  • Filament winding or Pullwinding manufactured workpiece can also be made with another process such as winding preimpregnated fiber webs into tubes.
  • the workpiece can be pre-cut to a certain length, but it can also be used as a piece of tubing initially unspecified
  • the cross-sectional profile of the workpiece may be constant or variable over its length.
  • the cross-sectional profile is limited only in that its largest
  • Expansion must be smaller than a cross section of a through hole of a device for producing the extruded profile.
  • the workpiece can be hollow or compact.
  • a longitudinal direction of extension means an extension in a direction parallel to the longest dimension of the respective component, e.g. the axis of the extruded profile, which may possibly also be bent, or the direction of the fibers.
  • a fiber is understood to mean a linear, flexible, elementary structure which consists of a pulp and has an outer fiber shape which is thin in relation to its length.
  • the fiber may be (quasi) endless or limited in length. Fibers can - without the support of an enveloping matrix - absorb no compressive forces in the longitudinal direction, but only tensile forces, since they buckle under pressure.
  • torsion means the effects of a force acting parallel to the base surface and tangential to the side surface of a body, which mainly turns the extruded profile about its longitudinal axis.
  • the hardening process may be solidification by lowering the temperature or in-situ polymerization, and in the case of thermosets by polymerization, in particular
  • Orientations of the fibers differ from each other.
  • the fibers are not oriented parallel to one another but intersect at a predetermined angle when viewed from above. Characterized in that more are provided on train than stress on claimable fibers, in particular such an extruded profile by the prevailing residual stress the inclination relative to the coil spring axis to press outward in the mold. Therefore, no inner mold is needed during curing. An inner mold is possibly only needed for a short time to arrange the extruded profile in the outer mold, but not during the actual curing. In other words, the fibers are oriented in such a way that the
  • Coil spring before curing tends to be in the radial direction with respect to the
  • the coil spring After curing, the coil spring has a length that is smaller than before curing. This shortening of the coil spring in a direction parallel to the helical spring axis is due to the special arrangement of the fibers. This effect is all the more pronounced the more tension is provided on fibers than on compression-loadable fibers.
  • the method produces a helical spring with a screw diameter that is slightly larger than before hardening, which must be taken into account when designing the shape.
  • Such a structure of the extruded profile also has the advantage that the helical spring produced is designed to be stronger on torsion resilient than coil springs, which are made of a composite material with an identical number of fibers, which are loaded on train and pressure.
  • the extruded profile may have a first layer structure of a first plurality of layers and a second layer structure of a second plurality of layers around the first layer structure.
  • Each layer of the first layer structure may comprise a plurality of fibers.
  • Each layer of the second layer structure may comprise a plurality of fibers.
  • the Fibers of the first plurality of layers and the fibers of the second plurality of layers may each extend in the longitudinal extension directions.
  • Longitudinal directions of the fibers of the first plurality of layers and the fibers of the second plurality of layers may differ from the longitudinal direction of the extruded profile.
  • the fibers of the first plurality of layers may extend relative to the longitudinal extension direction of the extruded profile in such a way that they are subjected to longitudinal pressure in the longitudinal direction when the torsion load of the extruded profile is set.
  • the fibers of the second plurality of layers may extend relative to the longitudinal extension direction of the extruded profile in such a way that they are subjected to longitudinal tension when the torsion load of the extruded profile is set in their longitudinal directions.
  • the second layer structure may comprise more fibers than the first layer structure.
  • a layer is to be understood as meaning a uniform mass of areal extent with a specific thickness which is significantly smaller than the dimensions which form the areal extent.
  • a layer may also be referred to as a layer in the field of the present invention.
  • a layer structure is understood to mean a design or a construction in which a plurality of layers are arranged one above the other or in which several layers are arranged one above the other.
  • Layer structure is surrounded to the outside by a second layer structure.
  • Both the first layer structure and the second layer structure are formed from a plurality of layers arranged one above the other. Each of the layers in turn has multiple fibers.
  • the first layer structure is surrounded by the layers of the second layer structure.
  • the turns or slopes of the fibers of the layers of the first layer structure differ from the turns or slopes to the fibers of the layers of the second
  • the fibers of the layers of the first layer structure are right-ascending and the fibers of the layers of the second layer structure are left-increasing or reverse-oriented. Accordingly, instead of a so-called fine-layered structure in which the layers of fibers of different turns are alternately stacked, a coarse-layered structure is proposed in which a first arrangement of layers with fibers of the same turn is provided one above the other, and then on this first arrangement a second arrangement of layers of fibers of the same turn is provided, wherein the turns of the fibers of the first arrangement differ from the turns of the fibers of the second arrangement.
  • Such a construction increases fatigue strength and reduces the shear modulus.
  • the outer mold may have a circumferential groove on an inner side, wherein the groove has a width which is greater than an outer diameter of the extruded profile when using a rigid material of the outer shape. Accordingly, the extruded profile is not flush the edges of the groove, but only in the radial direction with respect to the
  • Coil spring axis This excess facilitates Entform availability after curing.
  • the coil spring would not be removed because of undercuts.
  • the necessary size of the oversize depends not only on the number of moldings, but also on the position relative to the parting plane.
  • the groove in the demoulding direction, in the case of a two-shell structure perpendicular to the parting plane, the groove can be adapted to the profile.
  • the expansion for the undercut must be in accordance with the angle to the parting plane at the other positions between the parting plane and the demolding direction. An undercut is always created only on one side of the profile.
  • the method may further wind the extruded profile about an inner shape of the
  • Forming tool arranging the outer mold on the inner mold such that the extruded profile of the outer mold and the inner mold is surrounded, and removing the inner mold before
  • Curing the wound extruded profile include.
  • the inner mold can be removed, for example, by pulling out of the outer mold. Previously, the extruded profile is sandwiched by the outer mold and the inner mold. The inner mold serves only as an aid to correctly arrange the extruded profile in the outer mold and is not needed for fixing during curing.
  • the outer mold may be formed in several parts from a plurality of outer mold parts, wherein the extruded profile is arranged in at least one of the outer mold parts and to harden the extruded profile all outer moldings are interconnected.
  • the bonding is preferably not fixed, but releasable, such as by screwing.
  • the use of a multi-part outer mold facilitates demolding.
  • the outer moldings can be detached from each other.
  • the outer moldings can be easily removed, for example by
  • the inner mold can be removed non-reusable. This can be realized, for example, by irreversible destruction, disassembly, dissolution, melting out or the like. Non-reusable removal may facilitate or simplify removal because comparatively few operations are required.
  • the inner mold is removed reusable.
  • Hardening process can be used a new inner mold, which reduces the manufacturing cost of larger quantities.
  • the extruded profile can be arranged by unwinding from a support element and / or rotating in the outer mold.
  • the extruded profile can be adapted to different ones Arrange ways in the outer form.
  • the support element previously used only as an aid for a winding process to transport the extruded profile space saving after its production and can temporarily store.
  • the extruded profile can be formed as a clockwise-rotating compression spring, wherein the
  • Extruded profiles are claimed in their longitudinal directions to longitudinal pressure, are oriented clockwise to the longitudinal direction of the extruded profile, wherein the longitudinal extension directions of those fibers, the target torsional load of
  • the extruded profile can be formed as a left-handed compression spring, wherein the longitudinal extension directions of those fibers, the target torsional load of the
  • Extruded profiles are claimed in their longitudinal extension directions to longitudinal pressure, are oriented counterclockwise to the longitudinal direction of the extruded profile, wherein the longitudinal extension directions of those fibers, the target torsional load of the
  • a right-handed helical spring is to be understood as meaning a helical spring which, when viewed in the direction of the helical spring axis, is wound in a clockwise direction.
  • an orientation is at left-handed rotation
  • a left-handed helical spring is to be understood as a helical spring which, when viewed in the direction of the helical spring axis, is wound in a counterclockwise direction.
  • the fibers may be embedded in a matrix material.
  • a matrix material is to be understood as meaning any material which is suitable for fixing the fibers in their position after being deposited.
  • Thermoplastic polymers for example polyester resins, vinyl ester resins, polyurethane resins or epoxy resins, or thermoplastic polymers such as polyamides, polypropylenes or polyethylenes are preferably used as the matrix material, preferably high softening temperature, media resistance, fatigue resistance and ease of processing, adequate availability, resource-saving production, low To arrange purchase costs. It can be used in a layer structure of the fibers and different matrix materials.
  • the fibers of the first plurality of layers may be embedded in a first matrix material and the fibers of the second plurality of layers may be embedded in a second matrix material, wherein the second matrix material is different from the first matrix material.
  • the first matrix material may have a high stiffness to laterally pressurize the longitudinally pressurized fibers
  • the fibers may be impregnated with an impregnating agent.
  • an impregnating agent is basically to be understood as meaning any matrix material which is cured by curing, for example by polymerization, for bonding the fibers and
  • the impregnating agent in the context of the present invention, in particular a monomer or polymer-based liquid is used.
  • the impregnating agent can be a liquid matrix material during processing, such as, for example, a reactive liquid thermosetting system based on, for example, polyurethane, polyester, vinyl ester, epoxy resin, or a reactive thermoplastic system based on caprolactam, polyacrylic, or a thermoplastic Melt be based on polypropylene, polyethylene, polyamide, for example.
  • the fibers are glass fibers.
  • Such fibers are particularly easy to process and permanently stable or have a high fatigue strength.
  • a glass fiber is to be understood as meaning a long thin fiber made of glass. To produce thin threads are drawn from a glass melt.
  • the fibers may be formed as rovings. Under a roving in the present invention, a bundle, strand or multifilament yarn of parallel filaments, i. Continuous fibers, to be understood.
  • filaments produced from glass are preferably combined to form rovings, but other materials can in principle also be used within the scope of the present invention, for example aramids, basalt, polyethylenes or carbon.
  • a helical spring is proposed which is obtainable or obtained according to a method described above. Thus, the coil spring can be produced with the advantages of the method described above.
  • FIG. 1 shows a side view of an extruded profile in the form of a helical spring
  • FIG. 2 shows a further side view of the extruded profile in the form of a helical spring
  • FIG. 3 shows a side view of molded parts of a molding tool
  • FIG. 4 shows a detail of the outer shape of the molding tool
  • FIGS. 6A and 6B show an elastically deformable inner shape of a first exemplary embodiment
  • FIGS. 7A and 7B show an inner shape of a second embodiment
  • FIGS. 8A and 8B show a multi-part inner shape of a third exemplary embodiment
  • FIGS. 9A and 9B show a multi-part inner shape of a fourth exemplary embodiment
  • FIGS. 10A to 10D show various steps of a method for producing a
  • Figure 1 1 is a perspective view of a way to introduce the extruded profile in the outer mold.
  • Figure 1 shows a side view of an extruded profile 10.
  • the extruded profile 10 is bent in the form of a clockwise helical spring 12. Accordingly, the extruded profile 10
  • the coil spring 12 has an outer diameter d e of the extruded profile 10.
  • the extruded profile 10 may be rohrformig and thus have an inner diameter d.
  • the coil spring 12 also has a pitch H, a spring diameter D and a pitch angle a.
  • the Slope H is defined as the distance from centers of adjacent turns in a direction parallel to the helical spring axis 14.
  • the spring diameter D is as a distance from centers of adjacent turns in a direction perpendicular to
  • Coil spring axis 14 defined.
  • the pitch angle a is defined as an angle between a center line 16 of the extruded profile 10 and a plane 18 perpendicular to the helical spring axis 14.
  • Figure 2 shows a further side view of the extruded profile 10.
  • the coil spring 12 is more precisely a clockwise rotating compression spring, as indicated by arrows 20.
  • the extruded profile 10 extends in a longitudinal direction 22.
  • the extruded profile 10 is made of a fiber composite material.
  • the extruded profile 10 has one around the
  • Layer structure 24 has a first plurality of layers 26, of which only one is indicated in FIG.
  • the first layer structure 24 preferably consists of the first plurality of layers 26.
  • Each layer 26 of the first layer structure 24 has several
  • the fibers 28 of the first plurality of layers 26 each extend in longitudinal directions 30.
  • the extruded profile 10 also has a second
  • the second layer structure 32 has a second plurality of layers 34, of which only one is indicated in FIG.
  • the second layer structure 32 preferably consists of the second plurality of layers 34.
  • Each layer 34 of the second layer structure 32 has a plurality of fibers 36.
  • the fibers 36 of the second plurality of layers 34 each extend in longitudinal directions 38. As will be explained in more detail below, the fibers 28, 36 extend into their respective ones
  • Extruded profile 10 such that more fibers 28, 36 are claimed in the longitudinal direction of stretching of the extruded profile 10 in their longitudinal directions of extension 30, 38 on longitudinal tension than on longitudinal pressure.
  • the extruded profile 10 more fibers 36, which are claimed in the longitudinal extension directions 38 on longitudinal tension at nominal torsional load of the extruded profile 10, as fibers 28, which are claimed at nominal torsional load of the extruded profile 10 in their longitudinal directions 30 on longitudinal pressure.
  • the longitudinal extension directions 30 of the fibers 28 of the first plurality of layers 26 are each oriented to the longitudinal extension direction 22 of the extruded profile 10 at an angle with an amount in the range of 30 ° and 60 °.
  • the fibers 28 of the first plurality of layers 26 extend so relative to the longitudinal extension direction 22 of FIG.
  • the longitudinal extension directions 30 of the fibers 28 of the first plurality of layers 26 are oriented clockwise to the longitudinal direction 22 of the extruded profile 10 at an angle with an amount in the range of 30 ° to 60 °.
  • the longitudinal directions 38 of the fibers 36 of the second plurality of layers 34 are respectively oriented to the longitudinal extension direction 22 of the extruded profile 10 at an angle with an amount in the range of 30 ° and 60 °.
  • the fibers 36 of the second plurality of layers 34 extend in such relative to the longitudinal direction 22 of the extruded profile 10 that they at nominal torsional load of the extruded profile 10 in their
  • the longitudinal extension directions 38 of the fibers 36 of the second plurality of layers 34 are oriented counterclockwise to the longitudinal extension direction 22 of the extruded profile 22 at an angle with an amount in the range of 30 ° to 60 °.
  • the fibers 28 of the first plurality of layers 26 and the fibers 36 of the second plurality of layers 34 are glass fibers.
  • the second layer structure 32 surrounds the first
  • the second layer structure 32 comprises more fibers 36 than the first layer structure 24.
  • the number of fibers 36 of the second plurality of layers 34 is a factor of 1.2 to 9, preferably 1.5 to 9 , still
  • the first plurality of layers 26 and the second plurality of layers 34 may have different fiber volume fractions.
  • the first plurality of layers 34 has a fiber volume fraction of 40% to 70% based on the volume of the first layer structure 24 and the second plurality of layers 34 has a fiber volume fraction of 40% to 60% based on the volume of the second layer structure 32
  • the fibers 28 of the first plurality of layers 26 and the fibers 36 of the second plurality of layers 34 are each embedded in a matrix material.
  • the matrix material for the fibers 36 of the second plurality of layers 34 is optionally different from the matrix material for the fibers 28 of the first plurality of layers 26.
  • the matrix material for the fibers 28 of the first A plurality of layers 26 have a high rigidity and the matrix material for the fibers 36 of the second plurality of layers 34 has a high toughness.
  • the fibers 28 of the first plurality of layers 26 and the fibers 36 of the second plurality of layers 34 are impregnated with an impregnating agent.
  • the first layer structure 24 is optionally separated from the second layer structure 32 by a layer impermeable to the impregnant layer.
  • the fibers 36 of the second layer structure 32 are formed as rovings having a filament diameter that is optionally smaller than a filament diameter of the fibers 28 of the first layer structure 24.
  • the extruded profile 10 may have a core on which the first layer structure 24 is arranged.
  • the core may be an array of twisted fibers, a solid core, a jacketed solid core, a hollow core, or a jacketed hollow core.
  • the core can remain in the finished workpiece or be removed.
  • the longitudinal extension directions 30 of the fibers 28 of adjacent layers 26 of the first plurality of layers 26 differ by an angle in an amount in a range of 0 ° to 10 °, preferably 2 ° to 10 ° and more preferably 2 ° to 6 ° from each other.
  • the longitudinal directions 38 of the fibers 36 of adjacent layers 34 of the second plurality of layers 34 differ by an angle in an amount in a range of 0 ° to 10 °, preferably 2 ° to 10 ° and more preferably 2 ° to 6 °.
  • the extruded profile 10 and the coil spring 12 may be modified as follows.
  • the coil spring 12 may be formed as a left-handed compression spring.
  • the longitudinal directions 30 of the fibers 28 of the first plurality of layers 26 are oriented counterclockwise to the longitudinal direction 22 of the extruded profile 10 and the longitudinal directions 38 of the fibers 36 of the second plurality of layers 34 are oriented clockwise to the longitudinal direction 22 of the extruded profile 10.
  • the second layer structure 32 does not have to surround the first layer structure 42 in order to form a so-called coarse-layer structure. Instead, it is possible to arrange the layers 26 of the first layer structure 24 and the layers 34 of the second layer structure 32 in alternating order in order to realize a so-called fine-layered structure.
  • FIG. 3 shows a side view of molded parts of a molding tool 40 for producing the coil spring 12.
  • the molding tool 40 has an inner mold 42.
  • the inner mold 42 is formed substantially rod-shaped.
  • the inner mold 42 has a right-handed groove 44.
  • the groove 44 is semicircular and has a radius of half
  • the molding tool 40 further has an outer mold 46.
  • the outer mold 46 is formed in several parts from a plurality of outer mold parts 48. In the embodiment shown, the outer mold 46 has two
  • Outer moldings 48 of which only one is shown.
  • the outer mold 46 has on its inner side 50 a circumferential groove 52.
  • the groove 52 is dextrorotatory.
  • the outer mold 46 has in the region of the groove 52 an inner diameter which is at least as large as the spring diameter D of the coil spring 12 to be formed plus the outer diameter de of the extruded profile 10.
  • 4 shows an enlarged view of the inner side 50 in the region of a groove 52.
  • the groove 52 has a width 54 which, when using a rigid molding material of the extruded profile 10, is greater than an outer diameter de of the extruded profile 10 is.
  • FIG. 5 shows graphs of the groove width as a function of the number of outer moldings 48,
  • Outer diameter d e of the extruded profile 10 corresponds.
  • the Y-axis shows the ratio of groove width to rod radius.
  • the respective curves in the graphs are plotted as a function of spring pitch H relative to spring diameter D.
  • the above-described excess of the width 54 of the groove 52 serves to demould the coil spring 12 as will be described in more detail below and can be reduced with an increasing circumferential pitch of the outer mold 46, so increasing number of outer moldings 48, as the graphs of Figure 5 illustrate.
  • the inner mold 42 In order to remove the inner mold 42 from the outer mold 46 and from the extruded profile 10 prior to a curing process described in more detail below, the inner mold 42 must be changeable or destructible in size. In particular, the outer diameter of the inner mold 42 for removal must be made smaller, unless the inner mold 42 is to be destroyed.
  • FIGS. 6A and 6B show an inner mold 42 of a first exemplary embodiment which is elastically deformable.
  • Figure 6A shows a side view of the inner mold 42 of the first embodiment in an undeformed state.
  • Figure 6B shows a front view of the inner mold 42 of the first embodiment in the undeformed state.
  • the inner mold 42 has an outer diameter 58 which is larger than an outer diameter 60 in the region of the groove 44, as shown in Figures 6A and 6B.
  • the outer diameter 60 in the region of the groove 44 is determined based on the radially opposite points of the groove 44.
  • the inner mold 42 is shown in its elastically relaxed or undeformed state.
  • the inner mold 42 can be reduced at least in the region of the groove 44 in its outer diameter.
  • the inner mold 42 has in its reduced or deformed state (not shown in detail) a
  • the inner mold 42 of the first embodiment is made of an elastic material.
  • the inner mold is made of a foamed material such as foam or silicone. It is explicitly emphasized that the inner mold can be made in place of a deformable design such that these from the extruded profile 10 in front of a
  • Curing can be removed only by destroying, for example by dissolving
  • FIGS. 7A and 7B show an inner mold 42 of a second exemplary embodiment.
  • the same or comparable components compared to the previous embodiment are given the same reference numerals.
  • Figure 7A shows a side view of the inner mold 42 of the second embodiment.
  • Figure 7A shows a front view of the inner mold 42 of the second embodiment.
  • the inner mold 42 is formed in two parts and has a solid round core 62 and a flexible outer shell 64, which is arranged around the core 62 and in which the groove 44 is formed.
  • the outer jacket 64 is made of an elastic material.
  • the outer jacket 64 is made of a foamed material such as flexible foam or a cast material such as flexible silicone.
  • the inner mold 42 has an outer diameter 58 which is larger than that Outside diameter 60 in the region of the groove 44 is.
  • the core 62 has an outer diameter 66 which is smaller than the outer diameter 60 in the region of the groove 44.
  • the core 62 In order to remove the inner mold 42 from the extruded profile 10 before curing, the core 62 must first be removed from the outer jacket 64, for example by pulling out. Then, the outer jacket 64 can be compressed to remove it from the extruded profile 10, for example by pulling out.
  • FIGS. 8A and 8B an inner mold 42 of a third exemplary embodiment is shown, which is designed in several parts. The same or comparable components in comparison to the previous embodiments are given the same reference numerals.
  • Figure 8A shows a side view of the inner mold 42 of the third embodiment.
  • FIG. 8B shows a
  • the inner mold 42 is formed of nine inner moldings 68, which form a circular cross section in an assembled state. In this case, eight inner mold parts 68 are arranged around a middle inner mold part 68 around. In order to remove the inner mold 42 from the extruded profile 10 before curing, the middle inner mold part 68 is first removed,
  • FIGS. 9A and 9B an inner mold 42 of a fourth exemplary embodiment is shown, which is designed in several parts. The same or comparable components in comparison to the previous embodiments are given the same reference numerals.
  • Figure 9A shows a side view of the inner mold 42 of the fourth embodiment.
  • FIG. 9B shows a
  • the inner mold 42 is formed of six wedge-shaped inner moldings 68, which in a
  • Internal moldings 68 are radially displaceable.
  • the inner mold 42 is inflatable, so that the inner mold parts 68 are movable radially outward. By discharging the air or the like, the inner moldings 68 are movable radially inwardly. In order to remove the inner mold 42 from the extruded profile 10 before curing, the inner moldings 68 are moved radially inwardly.
  • the radial movement may also be e.g. be initiated by mechanical levers.
  • Figs. 10A to 10D show various steps of a method of manufacturing a coil spring 12.
  • the extruded profile 10 having the structure described above is provided.
  • the extruded profile 10 is made of a fiber-reinforced
  • the extruded profile 10 has a plurality of layers 26, 34, each having a plurality of fibers 28, 36, wherein the fibers 28 each extend in longitudinal directions 30, 36 relative to the longitudinal direction 22 of the extruded profile 10 such that more fibers at nominal torsional load of the extruded profile 10 in their
  • the Extruded profile 10 is then bent in the form of a coil spring 12, for example in the form of a clockwise rotating compression spring 12.
  • the bending can be done by means of free-form tools. Bending may include winding onto the inner mold 42 of the mold 40 such that the extruded profile 10 is located in the groove 44 of the inner mold 42, as shown in Figure 10A.
  • the outer mold 46 is arranged on the inner mold 42 such that the extruded profile 10 is surrounded by the outer mold 46 and the inner mold 42.
  • the extruded profile 10 is arranged in at least one of the outer moldings 48 and all outer moldings 48 are joined together, for example screwed, as shown in Figure 10B.
  • the extruded profile 10 is also located in the groove 52 on the inner side 50 of the outer mold 46. Accordingly, the extruded profile 10 is sandwiched by the outer mold 46 and the inner mold 42.
  • the inner mold 42 is removed, as shown in Figure 10C.
  • the inner mold 42 is removed in particular prior to curing of the wound extruded profile 10.
  • the inner mold 42 by an elastic deformation or reduction of the
  • the extruded profile 10 due to the particular arrangement of the fibers 28, 36 presses radially outward with respect to the helical spring axis 14, the extruded profile 10 can be removed from the groove 44 of the inner mold 42. Once the inner mold 42 is removed, the curing of the extruded profile 10 takes place in the outer mold 46. To cure the extruded profile 10, all outer moldings 48 are connected together. During curing, the extruded profile 10 is held exclusively by the outer mold 46 in its spring form. The curing process takes place in thermoplastic materials by solidification by temperature reduction or in situ polymerization. In the case of thermoset materials, the curing takes place by free-radical, catalytic or otherwise suitably initiated polymerization. The curing also take place thermally or be supported,
  • temperatures of 80 ° C to 150 ° C for a period of 1 hour to 6 hours wherein the temperature can be gradually increased or decreased.
  • the outer moldings 48 are released from each other, as shown in Figure 10D.
  • the outer moldings 48 are released from each other, as shown in Figure 10D.
  • the outer moldings 48 are released from each other, as shown in Figure 10D.
  • the extruded profile 10 may be formed as a spring bar, ie as an extruded profile with solid material, or spring tube, ie hollow inside, optionally including inner core.
  • the extruded profile 10 can be bent in the form of a left-handed helical spring 12.
  • the groove 44 of the inner mold 42 and the groove 52 of the outer mold 46 are also formed left-handed.
  • the inner mold 42 may be removed prior to curing of the extruded profile 10 instead of by elastic deformation reversibly deforming by pressure change similar to a bellows or sandbag, disassembly, twisting, mechanical twisting or displacements.
  • the inner mold 42 may be non-reusably removed prior to curing the extruded profile 10, for example by melting, dissolving or rinsing.
  • the extruded profile 10 can be arranged by unwinding from a support element and / or rotating in the outer mold 46, for example by unwinding from a pipe and controlled depositing in the grooves 44, 52 or spinning the outer mold 46 and the
  • Figure 1 1 shows a perspective view of an alternative possibility for introducing the extruded profile 10 in the outer mold 46, in which no inner mold 42 is required.
  • the extruded profile 10 is stored controlled by means of a rotating member 70 of an elongated or rectilinear shape in the groove 52 of the outer mold 46 and thus provided with a helical spring shape.
  • a spring-composite tube with an outer diameter d e 18.4 mm and an inner diameter d, 10 mm was produced as an extruded profile.
  • the following materials were used for the tested extruded profiles.
  • the fiber was a roving weighing 2400 g / km (2400 tex).
  • the system consisted of the resin bisphenol A diglycidyl ether with 22 wt .-% butanediol diglycidyl ether and the hardener diethylmethylbenzenediamine in
  • the fiber mass fraction was calculated by the amount of glass material used, core material, auxiliary materials and the total weight of the profiles for the system at 67% +/- 2%.
  • a predominantly dextrorotatory laminate of 3 plies each having 24 rovings with an orientation of -45 ° (i.e., dextrorotatory), + 45 °, + 45 ° (i.e., levorotatory) of the fibers was made with respect to the longitudinal direction of the extruded profile. The curing took place over 5 hours at 150 ° C.
  • the coil spring was formed with 4.5 turns.
  • the spring length before / after curing was 269 mm / 251 mm, which corresponds to a change in length of -7%.
  • the outer diameter d e before / after curing was 128 mm / 129 mm, which corresponds to a change in diameter of + 1%.
  • the outer diameter d e has therefore remained virtually constant.
  • the spring hose has twisted during curing so that the coil spring expanded outward and shortened in length.
  • the spring is round in cross-section and has been impressed evenly in the outer shape without collapsing inwards or buckling. Curing exclusively in the outer mold was successful without support.
  • an extruded profile with identical laminate orientation of the fibers was wound as a levorotatory spring on an inner mandrel having an outer diameter d e of 80 mm.
  • the spring length before / after curing was 269 mm / 289 mm, which is one
  • Length change of + 7% corresponds.
  • the inner diameter d before / after curing was 80 mm / 80 mm, which corresponds to a diameter change of 0%, i. the diameter has not changed.
  • the spring tube has twisted during curing so that the coil spring clamped inwards on the inner mold and stretched in length. Curing exclusively in an outer mold would not be possible with this combination of spring-rotation direction and laminate orientation, since only the inner mandrel prevented the spring from moving inwards and thus from an outer shape to move uncontrolled inward.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • General Engineering & Computer Science (AREA)
  • Springs (AREA)
  • Moulding By Coating Moulds (AREA)

Abstract

L'invention concerne un procédé de fabrication d'un ressort hélicoïdal (12), en particulier d'un ressort hélicoïdal (12) pour un châssis d'un véhicule à moteur. Le procédé comprend la fourniture d'un profilé extrudé (10), le profilé extrudé (10) étant fabriqué à partir d'un composite renforcé de fibres, le profilé extrudé (10) s'étendant dans une direction d'extension longitudinale (22), le profilé extrudé (10) comprenant plusieurs couches (26, 34) comprenant chacune plusieurs fibres (28, 36), les fibres (28, 36) s'étendant respectivement dans des directions d'extension longitudinale (30, 38) par rapport à la direction d'extension longitudinale (22) du profilé extrudé (10), de telle façon que plus de fibres (28, 36) sont soumises à une traction longitudinale qu'à une pression longitudinale en cas de charge de torsion théorique du profilé extrudé (10), la disposition du profilé extrudé (10) dans un moule externe (46) d'un outil de moulage (46) pour la fabrication du ressort hélicoïdal (12) et le durcissement du profilé extrudé (10) dans le moule externe (46), le profilé extrudé (10) étant maintenu dans la forme de ressort uniquement par le moule externe (46) durant le durcissement.
PCT/EP2018/070204 2017-07-25 2018-07-25 Procédé de fabrication d'un ressort hélicoïdal WO2019020703A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP17183051.6 2017-07-25
EP17183051 2017-07-25

Publications (1)

Publication Number Publication Date
WO2019020703A1 true WO2019020703A1 (fr) 2019-01-31

Family

ID=59399341

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2018/070204 WO2019020703A1 (fr) 2017-07-25 2018-07-25 Procédé de fabrication d'un ressort hélicoïdal

Country Status (1)

Country Link
WO (1) WO2019020703A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020229698A1 (fr) * 2019-05-16 2020-11-19 Basf Polyurethanes Gmbh Procédé de production de ressorts composites et de noyau de moule pour un tel procédé

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4260143A (en) 1979-01-15 1981-04-07 Celanese Corporation Carbon fiber reinforced composite coil spring
JPH07108620A (ja) * 1993-10-09 1995-04-25 Toho Rayon Co Ltd コイルスプリング成形型
WO1996014519A1 (fr) * 1994-11-07 1996-05-17 Mark Francis Folsom Ressorts en plastique renforces par des fibres
WO2012066246A1 (fr) 2010-11-19 2012-05-24 Peugeot Citroen Automobiles Sa Procede de fabrication d'un ressort en materiau composite, tel qu'un ressort de suspension notamment pour vehicule automobile
WO2015188963A1 (fr) * 2014-06-11 2015-12-17 Thyssenkrupp Ag Composant en forme de barre sollicité en torsion et pourvu de différents renforcements en fibres aux fins de sollicitation en traction et en pression

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4260143A (en) 1979-01-15 1981-04-07 Celanese Corporation Carbon fiber reinforced composite coil spring
JPH07108620A (ja) * 1993-10-09 1995-04-25 Toho Rayon Co Ltd コイルスプリング成形型
WO1996014519A1 (fr) * 1994-11-07 1996-05-17 Mark Francis Folsom Ressorts en plastique renforces par des fibres
WO2012066246A1 (fr) 2010-11-19 2012-05-24 Peugeot Citroen Automobiles Sa Procede de fabrication d'un ressort en materiau composite, tel qu'un ressort de suspension notamment pour vehicule automobile
WO2015188963A1 (fr) * 2014-06-11 2015-12-17 Thyssenkrupp Ag Composant en forme de barre sollicité en torsion et pourvu de différents renforcements en fibres aux fins de sollicitation en traction et en pression

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020229698A1 (fr) * 2019-05-16 2020-11-19 Basf Polyurethanes Gmbh Procédé de production de ressorts composites et de noyau de moule pour un tel procédé

Similar Documents

Publication Publication Date Title
EP1985465B1 (fr) Rayon, roue et procédé de fabrication d'un rayon, en particulier pour vélos
EP1798428B1 (fr) Pièce composite fabriquée par tressage
EP3178634B1 (fr) Procédé de fabrication d'un composant en matériau hybride
DE102011011577A1 (de) Verfahren zum Herstellen einer Drehstabfeder oder eines Wankstabilisator
EP0561151A1 (fr) Procédé pour la fabrication de supports en matières synthétiques renforcées de fibres pour pare-choc de véhicules ainsi que supports similaires
DE102015215077A1 (de) Achsstrebe
DE102011085962A1 (de) Innenprofilierte Welle aus Faserverbundwerkstoff mit Lasteinleitungselementen und Verfahren zur Herstellung
DE102010049563A1 (de) Verfahren zum Herstellen einer Drehstabfeder
WO2009112017A2 (fr) Procédé de fabrication d'une pale de rotor pour une installation éolienne et pale de rotor fabriquée selon ce procédé
DE102016002856A1 (de) Verfahren zur Herstellung eines Harzformgegenstands und Harzformgegenstand
DE102017219774A1 (de) Verfahren und Anlage zur Herstellung von Faser-Matrix-Verbund-Profilen mit axial rotierendem Querschnitt und einstellbarer Faserorientierung
EP3142843B1 (fr) Procédé de production d'un tube d'amortisseur à partir d'un matériau composite renforcé par des fibres pour amortisseur de vibrations
DE10226093B4 (de) Integral versteifte Verbundstoffantriebswelle
WO2018024667A1 (fr) Procédé pour la fabrication d'une pièce composite à fibres multicouche, tridimensionnelle
WO2019020703A1 (fr) Procédé de fabrication d'un ressort hélicoïdal
EP3332951B1 (fr) Noyau éclatable destiné à la fabrication d'un élément structural composite en fibres, utilisation d'un noyau éclatable et procédé de fabrication d'un élément structural composite en fibres
EP3568288A1 (fr) Profilé extrudé et procédé de fabrication d'un profilé extrudé
DE102013020871A1 (de) Strukturbauteil für ein Kraftfahrzeug
EP0311837B1 (fr) Profilé creux, en particulier tube, en matière synthétique renforcée de fibres longitudinales et procédé de réalisation de ce profilé
DE102018129549B9 (de) Gestaltung der Enden von Schraubenfedern
WO2016113024A1 (fr) Élément d'insertion pour tube renforcé par des fibres
EP3704397A1 (fr) Composant pour l'absorption d'énergie de choc
EP0564954B1 (fr) Plaque de maillon de chaîne et son procédé de fabrication
DE102020121709A1 (de) Verfahren zur Herstellung einer Zug-Druckstrebe sowie Zug-Druckstrebe
WO2023213465A1 (fr) Procédé de fabrication d'un renfort de capuchon polaire et récipient sous pression, et récipient sous pression ayant un renfort de capuchon polaire

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18742525

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18742525

Country of ref document: EP

Kind code of ref document: A1