DE102008057463C5 - Method and device for producing a spring from a fiber composite material - Google Patents

Abstract

Method for producing a spring (1) from a fiber composite material, characterized by the following method steps: S1: feeding a non-hardened fiber composite web (8) to a heating device (10) and drawing the fiber composite web (8) into a gap (9) between two heat rollers (W1, W2), which are arranged behind the heater (10) as seen in the conveying direction.S2: deflecting the fiber-composite web (8) by one of the two heating rollers (W1, W2) by less than 181 ° .S3: Stop the transport of the fiber composite web (8) .S4: actuating the heating device (10) and heating the heating roller (W1, W2) partially wrapped by the fiber composite web (8) .S5: curing an end section (2, 6) or a winding section (4, 5) under the heater (10) and simultaneous curing of a deflecting section (3) on the heating roller (W1, W2) .S6: further transport of the hardened end section (2, 6) or of the hardened winding section ( 4, 5) through the gap (9) of the two heating rollers (W1, W2) and simultaneous further transport of the hardened deflection section (3) by lifting the deflection section (3) from the heating roller (W1, W2) .S7: supplying and deflecting one still uncured section (1) of the fiber composite web (8) around the opposite heating roller (W2, W1) by less than 181 ° .S8: Continue with step S3 to step S7 until the desired length of the spring (1) is reached ist.S9: separation of the spring (1) when reaching a certain length (L) .S10: removal of the spring (1) and on to step S4.

Description

Method and device for producing a spring from a fiber composite material.

The invention relates to a method and an apparatus for producing a spring from a fiber composite material.

Springs are well known as structural elements of mechanical engineering. For example, there are leaf springs, disc springs, coil springs or coil springs, which are used in terms of their assigned task in different geometries, dimensions and properties, such as a tension spring, a compression spring or a torsion spring. Such springs are usually made of a spring steel, which gives the spring a different spring force depending on the design and dimension. Although such steel springs have a number of advantages, these are less well suited for some applications. Especially with comparatively large springs, their weight makes disadvantageous. Thus, in modern vehicle construction, the need for springs has arisen, which have the same or better properties than steel springs, but are still lightweight.

Against this background is from the DE 30 00 520 A1 a carbon fiber reinforced, helically wound spring and a process for their preparation has become known. This fiber composite coil spring is made of braided carbon fibers and an amount of a resin serving as a piling material for the braided fibers, wherein the carbon fibers are braided at an angle of about plus or minus 30 ° to plus or minus 60 ° to the strand axis.

To make such a carbon fiber reinforced coil spring is provided according to the method known from this document that one braided from carbon fibers strand in which fibers are braided at an angle of about plus or minus 30 ° to plus or minus 60 ° to the strand axis, impregnating a non-solidified resin serving as a substantially closed contiguous encapsulant, wrapping the strand so impregnated into a groove extending helically along the surface of a cylindrical mandrel, thereby giving the carbon fiber reinforced coil spring composite the helical shape, then resin which serves as an embedding material of the coil spring, and finally the solid spring decreases from the mandrel.

This manufacturing process is judged to be less practical, since in particular the molding of the solidified spring of the mandrel difficulties. In addition, can be realized with the known manufacturing process no continuous production process, whereby the manufacturing costs are relatively high in such a manufacturing process.

Moreover, from the AT 28 924 E a tension / compression spring element is known, which has a continuous, rectangular in cross-section fiber-reinforced plastic strip with reinforcing fibers in a plastic matrix, wherein the fibers are directed generally in the longitudinal direction of the strip. This spring element is characterized in that the strip is arranged in a relaxed state in a zigzag shape and consists of a plurality of members lying substantially in the same plane, wherein each adjoining pair of links at one end by a one-piece reflex-shaped connecting portion connected together are.

Next are from the DE 10 2008 006 411 A1 and the DE 10 2008 024 585 A1 generic spring elements are known, each having two end portions and arranged therebetween Windungsabschnitte, wherein the end portions and the Windungsabschnitte are integrally connected via deflecting sections, and in which all sections consist of a meandering folded path of a fiber composite material. Since these springs contain the same fiber composite material or the same ratio of fibers and set resin everywhere, their spring properties are not optimal in every respect.

Against this background, the invention has the object to provide a method and an apparatus for producing a spring made of a fiber composite material with which springs made of a fiber composite material can be produced continuously and inexpensively, which have different mechanical properties over their longitudinal extent.

The solution of this problem is achieved with a manufacturing method having the features of claim 1. A usable for this purpose manufacturing device is mentioned in independent claim 11. Advantageous embodiments and further developments are defined in the respectively associated subclaims.

The invention is based on the finding that a spring made from a fiber composite material is also produced by a meandering folding of a strand of prepreg material fed continuously to a production device is known, wherein the prepreg material is known to consist of synthetic fibers, which are embedded in a non-solidified resin matrix. A knowledge based thereon is that the individual, caused by the described folding of the prepreg material winding sections of such a spring must each harden sequentially in succession before the next turn section is produced by folding and cured. Finally, the invention made use of the knowledge that the mechanical properties of the spring over its longitudinal extension can be designed specifically by the formation of different fiber volume fractions in the respective spring sections.

• S1: Zuführen einer nicht ausgehärteten Faserverbundwerkstoff-Bahn zu einem Heizgerät und Einziehen der Faserverbundwerkstoff-Bahn in einen Spalt zwischen zwei Heizwalzen, die in Förderrichtung gesehen hinter dem Heizgerät angeordnet sind.
• S2: Umlenken der Faserverbundwerkstoff-Bahn um eine der beiden Heizwalzen um weniger als 181°.
• S3: Stopp des Transports der Faserverbundwerkstoff-Bahn.
• S4: Betätigen des Heizgerätes sowie der Heizung der von der Faserverbundwerkstoff-Bahn teilweise umschlungenen Heizwalze.
• S5: Aushärten eines Endabschnitts oder eines Windungsabschnitts unter dem Heizgerät und gleichzeitiges Aushärten eines Umlenkabschnitts auf der jeweiligen Heizwalze.
• S6: Weitertransport des ausgehärteten Endabschnitts oder des ausgehärteten Windungsabschnitts durch den Spalt der beiden Heizwalzen und gleichzeitiger Weitertransport des ausgehärteten Umlenkabschnitts durch Abheben des Umlenkabschnitts von der jeweiligen Heizwalze.
• S7: Zuführen und Umlenken eines noch nicht ausgehärteten Abschnitts der Faserverbundwerkstoff-Bahn um die gegenüberliegende Heizwalze um weniger als 181°.
• S8: Weiter mit Schritt S3 bis Schritt S7, solange, bis die gewünschte Länge der Feder erreicht ist.
• S9: Abtrennen der Feder bei Erreichen einer bestimmten Länge.
• S10: Abtransport der Feder und weiter mit Schritt S4.

According to the features of claim 1, the method for producing a fiber composite spring comprises the following method steps:

• S1: feeding a non-cured fiber composite web to a heater and drawing the fiber composite web into a nip between two heating rolls arranged downstream of the heater as seen in the conveying direction.
• S2: Redirecting the fiber composite web around one of the two heating rollers by less than 181 °.
• S3: Stop the transport of the fiber composite web.
• S4: Actuation of the heater as well as the heating of the heat roller partially looped around by the fiber composite web.
• S5: curing an end portion or a winding portion under the heater and simultaneously curing a deflection on the respective heating roller.
• S6: further transport of the cured end portion or the hardened Windungsabschnitts through the gap of the two heating rollers and simultaneous further transport of the hardened deflection section by lifting the deflection of the respective heating roller.
• S7: feeding and redirecting an uncured portion of the fiber composite web about the opposite heating roll by less than 181 °.
• S8: Continue with step S3 until step S7 until the desired length of the spring is reached.
• S9: separating the spring when reaching a certain length.
• S10: remove the spring and continue with step S4 ,

With this manufacturing method, springs formed according to the invention can be produced very cost-effectively from a fiber composite material in a continuous production process. The curing of the fiber composite web under the heater and on the heating rollers is preferably to achieve short cycle times only until these portions of the spring are sufficiently stiff to maintain their then existing geometric shape. The residual heat contained in these spring sections is used in the further procedure for complete curing of the same.

According to a development of this manufacturing method, it is provided that a planar or only slightly curved section of the fiber composite material web is hardened to an end section or to a winding section under the heater. Although this manufacturing feature is preferred, so it is not excluded, the end and winding sections harder curved more or less, if required by the desired geometry of the spring to be produced.

In order to have present at the beginning of the production of springs according to the invention a spring section with which the future spring is held under tension and wrapped with a not yet cured section around the respective heating roller is provided according to a further embodiment, that at the beginning of the manufacturing process exclusively under the heater and before the heating rollers, a flat or slightly curved portion of the fiber composite web is cured to an end portion.

In addition, it can be provided that the deflecting and pressing of the not yet cured fiber composite material web on the respectively associated heating roller by means of at least one pressing and deflection roller takes place. This process step ensures that the fiber composite material web rests smoothly and over the entire area on the respective heating roller and can harden under the influence of a tensile stress under the heating device and that on the heating roller.

In order to produce a circumferential geometry of the spring to be produced, which largely corresponds to a conventional coil spring made of spring steel, and to produce an accumulation of material in the region of the deflection, is provided according to a further embodiment that the guidance and shaping of the not yet cured fiber composite material -Bahn in front of the heater and / or on the heating rollers so that the spring has a circumferential geometry with straight at the deflection sections and between these deflection sections a circular segment-shaped course.

In this context, it is therefore considered to be very advantageous if the manufacturing process is operated so that the guidance and shaping and the adjustment of the fiber volume fraction of the not yet cured fiber composite material web before the heater and / or on the heating rollers takes place so that the fiber volume fraction the respective deflection sections, end sections or turn sections are smaller than the fiber volume portion of the respectively adjacent sections, wherein the setting of the respective fiber volume fraction is achieved by a section-wise pressing out of not yet hardened synthetic resin from the supplied fiber composite material web.

Alternatively, it can be provided that the guidance and shaping of the not yet cured fiber composite material web before the heater and / or on the heating rollers is performed so that the fiber volume fraction of the respective deflection sections, end sections or turn sections is equal to the fiber volume fraction of each adjacent Sections, wherein the adjustment of the respective fiber volume fraction is achieved by a section-wise pressing out of not yet hardened synthetic resin from the supplied fiber composite web.

According to a third alternative in this regard, it may be provided that the guidance and shaping of the as yet uncured fiber composite web in front of the heater and / or on the heating rollers is performed so that the fiber volume fraction of the respective This text has been adopted by the DPMA from original sources. It contains no drawings. The presentation of tables and formulas can be unsatisfactory. Deflection sections, end portions or turn sections is greater than the fiber volume fraction of each adjacent sections, wherein the adjustment of the respective fiber volume fraction is achieved by a sectionwise pressing out of not yet hardened resin from the supplied fiber composite web.

Accordingly, the spring for adjusting the concrete spring characteristics of portions of the spring is manufactured so that the fiber volume fraction of the respective deflection sections, end sections and turn sections is smaller, equal to or greater than the fiber volume portion of the respective adjacent deflection sections, end sections and turn sections. The adjustment of the respective fiber volume fraction is achieved by a section-wise pressing out of not yet hardened synthetic resin from the supplied fiber composite material web.

For setting and fixing the pitch angle α the winding sections of the spring can be provided according to a further method step, that the pitch angle α the winding sections are made by pivoting the heating rollers about a certain Verschwenkweg above or below the plane in which the fiber composite material web is below the heater.

• - eine Zuführzone zum Zuführen von wenigstens einer Prepreg-Bahn zur Bildung einer Faserverbundwerkstoff-Bahn,
• - eine in Transportrichtung folgende und im Wesentlichen geradflächige Heizzone mit einem Heizgerät zum Formen und Aushärten von geradflächigen End- und Windungsabschnitten der Feder,
• - eine in Transportrichtung nach der Heizzone folgende Umlenkzone zum Formen und Aushärten von gekrümmten Umlenkabschnitten der Feder,
• - zwei in der Umlenkzone gegenüberliegend angeordnete Heizwalzen, die einen Spalt zur Aufnahme der Faserverbundwerkstoff-Bahn zwischen sich bilden,
• - ein Anpress- und Umlenkmittel zum wechselseitigen Auflegen und Anpressen von noch nicht ausgehärteten Abschnitten der Faserverbundwerkstoff-Bahn an eine der beiden Heizwalzen, und
• - eine Trennvorrichtung zum Abtrennen von Federn vorbestimmter Länge von dem kontinuierlich hergestellten Verlauf der Feder.

In order to carry out the described manufacturing process, a manufacturing apparatus for producing a spring made of a fiber composite material is necessary, which will be briefly described below. This device is characterized by the following device components:

• a feed zone for feeding at least one prepreg web to form a fiber composite web,
• a heating zone following in the direction of transport and essentially flat, with a heating device for shaping and curing straight-sided end and winding sections of the spring,
• a deflection zone following the heating zone in the direction of transport for shaping and curing curved deflecting sections of the spring,
• two heating rollers arranged opposite one another in the deflection zone, which form a gap between them for receiving the fiber-composite material web,
• - A pressing and deflecting means for mutual laying and pressing of not yet cured sections of the fiber composite web to one of the two heating rollers, and
• - A separator for separating springs of predetermined length from the continuously produced course of the spring.

The pressing and deflecting means may be formed by one or more rollers or domes or rods. In addition, it can be provided according to a modification that under the heater curved end and turn sections can be produced. Since the diameter of the heating rollers determines the deflection radius of the deflection sections of the fiber composite spring, these are preferably designed to be interchangeable in order to be able to produce different spring charges.

In addition, it is judged to be very advantageous if in this manufacturing device, a tensioning device is provided, with which in cooperation with the feed force of the two driven heat rollers, a tensile force on the fiber composite web during their curing can be generated.

Further, in this manufacturing device is preferably provided that in the region of the feed zone and / or immediately in front of the two heat rollers and / or on the two heat rollers depositing and / or mold tools can be attached to the not yet cured fiber composite web, with which the circumferential geometry and / or the fiber volume fraction of portions of the spring to be produced.

For this purpose, the surfaces of the two heating rollers can themselves be designed as a mold tool for forming and / or adjusting the fiber volume fraction of the not yet cured fiber composite web, so that different peripheral geometries and spring properties can be brought about reproducibly.

Thus, the surfaces of the two heating rollers and / or said laying and / or mold tools may be formed in the region of the feed zone such that the width of the fiber composite material can be reduced in width and in the material thickness thereof in the region of the later deflection sections transversely to their longitudinal extension is enlargeable, or that the fiber volume fraction in the Umlenkabschnitten over the adjacent Windungsabschnitten by pressing out excess resin is increased.

Finally, the manufacturing device preferably has a pivoting device, with which the heating rollers are pivotable above and below that plane in which the fiber composite material web lies under the heater or which is spanned by the conveyor belt of the transport device. By such a pivoting of the heating rollers, the pitch angle can be α set under which the Windungsabschnitte are employed transversely to the longitudinal extent of the spring.

• 1 eine schematische Seitenansicht einer erfindungsgemäß ausgebildeten und hergestellten Faserverbund-Feder,
• 2 die Feder der 1 in perspektivischen Sicht A auf eine Stirnseite derselben,
• 3 eine schematische Darstellung einer Herstellvorrichtung zur Herstellung der Feder gemäß 1,
• 3a eine schematisch Draufsicht auf zwei übereinander gelegte Prepreg-Bahnen,
• 4 bis 11 schematische Darstellungen von weiteren Produktionsschritten zur Herstellung einer erfindungsgemäßen Feder,
• 12 eine schematische Darstellung eines letzten Produktionsschrittes zur Herstellung einer erfindungsgemäßen Feder.

Hereinafter, a fiber composite spring produced according to the invention, a production apparatus therefor and the process steps necessary for producing the spring will be explained with reference to exemplary embodiments with the aid of a drawing. In this shows

• 1 a schematic side view of an inventively designed and manufactured fiber composite spring,
• 2 the spring of 1 in perspective view A on a front side of the same,
• 3 a schematic representation of a manufacturing apparatus for producing the spring according to 1 .
• 3a a schematic plan view of two superimposed prepreg webs,
• 4 to 11 schematic representations of further production steps for producing a spring according to the invention,
• 12 a schematic representation of a final production step for producing a spring according to the invention.

The 1 and 2 show schematically in a side view and in a frontal plan view A a tension or compression spring 1 , which is made of a fiber composite material according to the described method steps. The spring 1 extends along a longitudinal axis Lx and two transverse axes aligned perpendicular thereto Ly and lz , wherein the transverse axis Lz in 1 is perpendicular to the paper plane of the drawing. The spring 1 points in the side view according to 1 Although the shape of a coil spring, but it has no continuous from one axial end to the other axial end, a helix following course. The spring 1 instead has about a geometry, as they would have a regular along its longitudinal extent meandering folded rectangular sheet of paper.

Accordingly, the spring has 1 at the respective axial ends via an upper end portion 2 and a lower end portion 6 in the illustrated embodiment substantially with non-curved surfaces 12 . 12 ' formed and parallel to one through the transverse axes Ly and lz aligned plane. Starting from the lower end section 6 follows one in the direction of the longitudinal axis Lx curved deflection section 3 , which at its other end with a meandering section 4 is integrally connected. This is also followed in one piece by another deflection section bent in the opposite direction to the first deflection section 3 which in the following with a second winding section 5 is integrally connected. This is how the spring settles 1 to its upper end portion 2 from a regular sequence of deflecting sections 3 and winding sections 4 . 5 together.

In the area of the deflection sections 3 To set a desired fiber volume fraction, the mechanical properties of the spring 1 affects the spring 1 on its outer circumference in the area 3c the end sections 2 , 6 and the winding sections 4 . 5 be shaped such that the deflection sections 3 essentially straightforward (see view B ) and in the intervening areas 3a . 3b are formed substantially circular segment-shaped.

If the fiber volume fraction in the region of the deflection sections 3 is to be increased, this is in the range of the deflection 3 by squeezing out of not yet set Synthetic resin reached and thereby simultaneously the thickness of the deflection sections, for example, the same or approximately the same as that of the adjacent spring sections held.

Unless the technical constraints in the use of such a spring 1 require, this spring can also with an axial bore 7 be provided, which only one or both end portions 2 . 6 or all end sections 2 . 6 and all turns sections 4 . 5 penetrates. These all end sections 2 . 6 and all turns sections 4 . 5 penetrating axial bore 7 is in the perspective view according to the 2 good to see.

In 3 is a production plant for producing a spring according to the invention 1 made of fiber composite material shown schematically. As the right half of the drawing illustrates, there are two prepreg rolls 16 and 17 Prepreg sheets 14 or. 15 unrolled. Between two prepreg layers on the prepreg rollers 16 . 17 present release agent 26 . 27 (such as paper) is also used by the rollers 16 and 17 removed and rolled up separately. The two prepreg webs 14 and 15 are then in the range of a tensioner 25 merged, in such a way that the two prepreg webs 14 . 15 lie flush against each other and then a fiber composite web 8th form (see also 3a) , About the tension pulley 25 At least one weight acts fg and an axial tensile force Fx on the fiber composite web 8th , whereby the fibers of the fiber composite web 8th stay aligned parallel to each other.

The fiber composite web 8th is in the middle section of the 3 from a transport device 19 towards a heater 10 and two in the transport direction 21 seen behind the heater 10 arranged, opposite heating rollers W1 and W2 transported. The transport device 19 consists of a heat-resistant conveyor belt 20 which on rollers 22 guided and of these in the transport direction 21 is driven.

Between the fiber composite web 8th and the conveyor belt 20 can, as in the embodiment shown, a separation and isolation track 18 be arranged, which of a roll 23 unwound and after leaving the conveyor belt 20 on the same or a different role 24 is wound up.

The transport device 19 has a feed zone Z and one in the direction of transport 21 adjoining heating zone H1 on. In the feed zone Z is a mold 28 arranged on the conveyor belt 20 or on the fiber composite web 8th is arranged lowerable. With this mold 28 can be made from the two prepreg sheets 14 and 15 existing fiber composite web 8th be shaped so that a desired geometry of the fiber composite spring to be produced 1 can be generated. Forming the fiber composite web 8th For example, by an at least partially constricting this web 8th take place, resulting in certain sections material accumulations or material reductions in the fiber composite web 8th result. Such or another or further mold 28 can to fulfill the same purpose in the area of the two heating rollers W1 . W2 be arranged and lowered to this for the purpose of shaping (not shown).

In the heating zone H1 is as mentioned before the heater 10 arranged, which, for example, electrically or in other ways dotted drawn thermal radiation on the fiber composite material web 8th can radiate. As an alternative to the illustrated device, the heater 10 also below the conveyor belt 20 be arranged, and from below on the fiber composite web 8th for at least partially curing the same act. Regardless of the arrangement of the heater 10 This serves to make sure that in the area of this heater 10 located portion of the fiber composite web 8th if it is cured so that it is a mechanically rigid, so at least by the influence of gravity does not permanently deformable structure.

The free end 13 the fiber composite web 8th is through by the two heating rollers W1 and W2 formed gap 9 guided and protrudes through this far from the heater 10 therethrough. The two heating rollers W1 and W2 be with a contact pressure fp on the fiber composite web 8th Pressed, which is set so that on the one hand a desired geometric shape of the future spring 1 can be generated and on the other hand, if necessary, excess resin from the fiber composite web 8th is pressable out.

In a deflection zone U indicating the location of the two heating rollers W1 . W2 includes, are two pressure and deflection rollers W3 and W4 arranged, which work alternately and with their help in each case a non-hardened section 11 the fiber composite web 8th on the respective heating roller W1 or. W2 to form the deflection section 3 can be stored and pressed.

The two heating rollers W1 and W2 can be operated constantly heating while the heater 10 heat only on the fiber composite web during certain periods of time 8th emits. Due to this structure, it is possible that in the heating zone H1 in the area of the heater 10 an end section 2 , 6 or a winding section 4 , 5 of the future spring 1 is cured while in the feed zone Z and in the deflection zone U located sections 11 the fiber composite web 8th initially not remain cured.

If the under the heater 10 lying portion of the fiber composite web 8th Hardened, this fiber composite web becomes 8th so far in the direction 21 through the gap 9 the two heating rollers W1 . W2 transported, the previously in the feed zone Z located and not yet cured portion of the fiber composite web 8th in the deflection section U is arranged. Here is this not yet cured section of the web 8th through one of the two pressure and deflection rollers W3 or W4 on the surface of one of the two heating rollers W1 or W2 pressed and this track section 11 then on this heat roller W1 or W2 hardened. At the same time or after the heater can also 10 be active, so that too in the range of this heater 10 located portion of the fiber composite web 8th is cured.

By alternately applying the not yet cured portion of the fiber composite web 8th on the heating roller W1 or W2 a folding of the fiber composite web takes place 8th resulting in a continuous product strand from which springs 1 . 1' can be cut off predetermined length.

In the 1 shown slope α the winding sections 4 . 5 the feather 1 can be according to the manufacturing device 3 by an alternating pivoting of the two heating rollers W1 or. W2 set that to a Schenkweg V (a) are arranged pivotally above and below that plane in which the fiber composite material web 8th under the heater 10 lies or which by the conveyor belt 20 the transport device 19 is stretched.

The 3 to 12 show the production of a spring according to the invention 1 in the manufacturing device according to 3 with the manufacturing steps S0 to S11 in detail. In 3 is the production step S0 as already explained. At the beginning of the manufacturing process is the free end 13 the fiber composite web 8th through the gap 9 the two heating rollers W1 and W2 plugged and only the heater 10 is activated, leaving a first, straight section of the web 8th is cured.

The adjustment of the fiber volume fraction of sections of the spring 1 can be done in all production phases, which are before the curing of the resin.

4 shows the next production step S1 in which the already cured portion of the fiber composite web 8th together with an uncured section 11 with the help of the pressure and deflection roller W4 around the heating roller W2 are diverted. Under the non-active heater 10 is also a not yet cured portion of the fiber composite web 8th arranged.

In 5 are the following process steps S3 . S4 and S5 shown in which the transport of the fiber composite web 8th stopped and the heat roller W2 as well as the heater 10 heat. This will be the heat roller around W2 looped section as well as under the heater 10 arranged section of the railway 8th hardened. In 5 is also hinted that the initially free end 13 the fiber composite web 8th cut off early.

As 6 is removable after curing of the heat roller W2 looped section and the curing of the under the heater 10 arranged portion of the fiber composite web 8th the transport device 19 reactivated, so that according to production step S6 of a cured web portion of the heat roller W2 lifts off and the other cured track section through the gap 9 the two heating rollers W1 . W2 is pushed through. 6 illustrates that the straight and already cured track sections the lower end section 6 and the first turn section 4 the future spring 1 according to 1 form while on the heating roller W2 cured section the deflection section 3 forms.

In 7 is the production step S7 shown in which again a not yet cured portion of the fiber composite web 8th through the gap 9 the two heating rollers W1 and W2 transported through and then with the help of the pressure and deflection roller W3 on the heating roller W1 is deposited and pressed. The heater 10 is switched off.

8th shows how again according to the production steps S3 to S5 on the heating roller W1 and under the heater 10 arranged and not yet cured sections of the fiber composite web 8th be cured by the action of heat energy (dotted lines). Above the heating roller W1 are already produced and therefore already hardened sections of the future spring 1 recognizable.

In 9 and 10 are the production steps S6 and S7 shown in which step S6 on the heating roller W1 cured section of the fiber composite web 8th by further transporting them through the gap 9 of both heating rolls W1 . W2 from the heating roller W1 has lifted and the under the heater 10 cured section through this gap 9 was passed through. In step S7 becomes another fed and uncured section of the fiber composite web 8th by means of the pressure and deflection roller W4 on the heating roller W2 put on and pressed. The heater 10 is switched off and both heating rollers W1 . W2 can also be switched off.

In 11 is shown in an overview, as the production steps S4 and S5 just expire while already having a larger number of end sections 2 . 6 , Deflection sections 3 and winding sections 4 . 5 is made. As the number of these sections 2 . 3 . 4 . 5 . 6 for the production of a spring 1 with the length L already big enough, will be in one production step S9 a separator 29 activated, which is the spring 1 from the course of the next, still in the making spring 1' separates. The finished spring 1 becomes in a production step S10 removed and the manufacturing device according to 3 continuously operated.

Finally, in 12 an optional production step S11 in which by means of a in the direction of movement 31 guided drill 30 a central hole 7 in all end sections 2 . 6 and winding sections 4 . 5 the feather 1 is introduced.

LIST OF REFERENCE NUMBERS

1

feather

1'

Spring history

2

Upper end portion of the spring

3

deflection section

3a

Peripheral portion of the spring

3b

Peripheral portion of the spring

3c

Peripheral portion of the spring

4

turn section

5

turn section

6

Lower end portion of the spring

7

Axial bore in the spring

8th

Fiber composite material-Bahn

9

Gap between the two heating rollers

10

heater

11

Unhardened section of the track 8th

12

Surface of the end section 2

12 '

Surface of the end section 6

13

Free end of the fiber composite web

14

Prepreg-Bahn

15

Prepreg-Bahn

16

Prepreg role

17

Prepreg role

18

Separating and insulating web

19

transport device

20

conveyor belt

21

transport direction

22

Role of the transport device

23

Separating and insulating agent roll

24

Separating and insulating agent roll

25

idler

26

release agent

27

release agent

28

Forming tool for deflection sections 3

29

separating device

30

drill

31

Direction of movement of the drill

A

Front side of the spring

B

Side view of the spring

fg

Weight of the tension pulley 25

fp

Pressing force of the heating rollers W1 . W2

Fx

Tensile force on the fiber composite web 8th

H1

Heating zone under the heater

L

Length of the spring

Lx

Longitudinal axis of the spring

Ly

Transverse axis of the spring

U

deflection

S0-S11

steps

V (a)

Swivel path of the heating rollers W1 . W2

W1

heating roller

W2

heating roller

W3

Pressing and deflection roller, pressing and deflection

W4

Pressing and deflection roller, pressing and deflection

Z

feed zone

α

Gradient of a meandering section 4 . 5

Claims (16)

Method for producing a spring (1) from a fiber composite material, characterized by the following method steps: S1: feeding a non-hardened fiber composite web (8) to a heating device (10) and drawing the fiber composite web (8) into a gap (9) between two heating rollers (W1, W2), which are arranged behind the heater (10) as seen in the conveying direction. S2: deflecting the fiber composite web (8) by one of the two heating rollers (W1, W2) by less than 181 °. S3: Stop the transport of the fiber composite web (8). S4: Actuating the heater (10) and the heating of the heating roller (W1, W2) partially looped around by the fiber-composite material web (8). S5: curing an end section (2, 6) or a winding section (4, 5) under the heater (10) and simultaneously curing a deflection section (3) on the heating roller (W1, W2). S6: further transport of the hardened end section (2, 6) or of the hardened turn section (4, 5) through the gap (9) of the two heating rollers (W1, W2) and simultaneous further transport of the hardened deflection section (3) by lifting off the deflection section (3) from the heating roller (W1, W2). S7: feeding and deflecting a not yet cured portion (1) of the fiber composite web (8) to the opposite heating roller (W2, W1) by less than 181 °. S8: Go to step S3 to step S7 until the desired length of the spring (1) is reached. S9: cutting off the spring (1) when reaching a certain length (L). S10: removal of the spring (1) and on to step S4. Method according to Claim 1 , characterized in that under the heater (10) a flat or only slightly curved portion of the fiber composite material web (8) to an end portion (2, 6) or to a winding section (4, 5) is cured. Method according to Claim 1 or 2 , characterized in that at the beginning of the manufacturing process only under the heater (10) and before the heating rollers (W1, W2), a plump or only slightly curved portion of the fiber composite material web (8) to an end portion (2, 6) is cured. Method according to one of Claims 1 to 3 , characterized in that the deflection and a pressing of the not yet cured fiber composite material web (8) on the respectively associated heating roller (W1, W2) by means of at least one pressing and deflecting roller (W3, W4) take place. Method according to one of Claims 1 to 4 , characterized in that the portion of the fiber composite material web (8) curing under the heating device (10) and on the heating roller (W1, W2) is subjected to a tensile force (Fx) during curing. Method according to one of Claims 1 to 5 , characterized in that the guidance and shaping of the uncured fiber composite web (8) in front of the heater (10) and / or on the heating rollers (W1, W2) is performed so that the spring (1) has a circumferential geometry with The deflecting sections (3) straight course (3c) and between these deflecting sections (3) has a circular section-shaped course (3a, 3b). Method according to one of Claims 1 to 6 , characterized in that the guidance and shaping of the not yet cured fiber composite material web (8) before the heater (10) and / or on the heating rollers (W1, W2) is performed so that the fiber volume fraction of the respective deflection sections (3), End sections (2, 6) or turn sections (4, 5) is smaller than the fiber volume fraction of the respective adjacent sections (2, 3, 4, 5, 6), wherein the adjustment of the respective fiber volume fraction by a sectionwise pressing out of not yet hardened resin from the supplied fiber composite web (8) is achieved. Method according to one of Claims 1 to 6 , characterized in that the guidance and shaping of the not yet cured fiber composite material web (8) in front of the heater (10) and / or on the heating rollers (W1, W2) is performed so that the fiber volume fraction of the respective deflection sections (3), end sections (2, 6) or turn sections (4, 5) is the same size as the fiber volume portion of the respective adjacent sections (2, 3, 4, 5, 6), wherein the setting of the respective fiber volume fraction by a section Extraction of not yet set resin from the supplied fiber composite web (8) is achieved. Method according to one of Claims 1 to 6 , characterized in that the guidance and shaping of the not yet cured fiber composite material web (8) before the heater (10) and / or on the heating rollers (W1, W2) is performed so that the fiber volume fraction of the respective deflection sections (3), End sections (2, 6) or Windungsabschnitte (4, 5) is greater than the fiber volume fraction of each adjacent sections (2, 3, 4, 5, 6), wherein the setting of the respective fiber volume fraction by a sectionwise pressing out of not yet hardened resin from the supplied fiber composite web (8) is achieved. Method according to one of Claims 1 to 9 , characterized in that the pitch angle (a) of the winding sections (4, 5) in the spring (1) by a pivoting of the heating rollers (W1, W2) by a certain Verschwenkweg V (a) above or below that plane takes place in the the fiber composite web (8) is below the heater (10). A device for producing a spring from a fiber composite material, characterized by - a feed zone (Z) for feeding at least one prepreg web (14, 15) to form a fiber composite web (8), - in the transport direction (21) following and in Substantially straight heating zone (H1) with a heating device (10) for shaping and curing straight-sided end sections (2, 6) and turn sections (4, 5) of the spring (1), - a deflection zone following in the transport direction after the heating zone (H1) ( U) for shaping and curing curved deflecting sections (3) of the spring (1), - two heating rollers (W1, W2) arranged opposite one another in the heating zone (H1) and having a gap (9) for receiving the fiber-composite web (8) form between them, - a pressing and deflecting means (W3, W4) for mutual laying and pressing of not yet cured sections (11) of the fiber composite web (8) to one of the two heating rollers (W1, W2), - and a Trennv orrichtung (29) for separating springs (1) of predetermined length (L) of the continuously produced course of the spring (1 '). Device after Claim 11 , characterized in that a tensioning device (25) is provided, with which in cooperation with the feed force of the two driven heating rollers (W1, W2), a tensile force (Fx) on the fiber composite material web (8) during their curing can be generated. Device after Claim 11 or 12 , characterized in that in the region of the feed zone (Z) and / or immediately before the two heating rolls (W1, W2) and / or on the two heating rolls (W1, W2) molding tools (28) to the not yet cured fiber composite web ( 8) can be applied, with which the circumferential geometry and / or the fiber volume fraction of sections (2, 3, 4, 5, 6) of the spring to be produced (1) can be adjusted. Device according to one of Claims 11 to 13 , characterized in that the surfaces of the two heating rollers (W1, W2) are formed as forming tools for forming and / or adjusting the fiber volume fraction of the not yet cured fiber composite web (8). Device according to one of Claims 13 or 14 , characterized in that the surfaces of the two heating rollers (W1, W2) and / or the depositing and / or forming tools (28) in the region of the feed zone (Z) are formed such that with them the fiber composite web (8) in The width of the later deflection sections (3) can be reduced in width and increased in their material thickness (D2), or the fiber volume fraction in the deflection sections (3) can be enlarged relative to the adjacent turn sections (4, 5) by pressing out excess resin , Device according to one of Claims 11 to 15 characterized in that the two heating rollers (W1, W2) for adjusting the pitch angle (a) of the winding sections (4, 5) of the spring (1) by means of a pivoting device about a pivoting path V (a) are pivotable above and below that plane, in which the fiber composite material web (8) lies under the heating device (10) or which is stretched by the conveyor belt (20) of the transport device (19).

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