JPH08312699A - Near-net-shaped fibrous structure and manufacture thereof - Google Patents

Abstract

PURPOSE: To efficiently provide a fiber structure by providing a flat layered body made of a fiber material, manufacturing one layer with two parts adjacent transversely of a fiber tape narrower than the fiber structure, punching the layered body with a needle, and cross-linking the layer with a fiber orthogonal to the surface of the layer. CONSTITUTION: A preform disk 100 is formed from an OPF tow 12 together punched with a needle subsequently, and comprises one or more symmetrical spiral rotation bodies 101 around a shaft, 99 of flat and partially overlapped blades 102, 103. Ears 156, 157 adjacent transversely of the blades 102, 103 are overlapped. After the finishing, the preform disk 100 is similar to a frictional disk in appearance. Parallel blades 102, 103 are inserted between one or more additional spirally wound fiber tapes, a flat ring having a plurality of fiber layers inserted into them before needle punching is formed. Thus, cut junk fiber can be minimized.

Description

Detailed Description of the Invention

The invention relates to carbon and / or ceramics (including mixtures thereof) fiber reinforced carbon and / or ceramics (including mixtures thereof).
TECHNICAL FIELD The present invention relates to a fiber support for producing a composite and a method for producing the same. An example of such a composite is a carbon fiber / carbon matrix brake disc made by depositing a carbon matrix on a carbon fiber support of the present invention, the support fiber material being carbonized to produce carbon. Reinforce the carbon matrix with fibers. The deposition of carbon on a substrate is the in-situ decomposition of carbon-containing gas (hereinafter carbon deposition, "CVD").
Abbreviated, or carbon vapor infiltration, abbreviated as "CVI", which terms are used interchangeably for the purposes of the present invention) or by repeated impregnation of a carbon-containing resin and subsequent such impregnation. It is carried out by densifying the carbon on the carbonized support, by means of various reductions of carbonization or a combination of such methods. The present invention is not for the formation of a carbon matrix or densification of a support for carbon fibers, but rather for use as a friction disk in a support, its manufacture and subsequent known methods, especially carbon fiber reinforced composites, especially brakes or clutches. Densification to form a complex of

The support according to the invention can be produced from virgin fibers or from recycled fibers derived from composites, or preforms formed from carbon fibers or carbon fiber precursors. Can be A preferred material for use in the present invention is polyacrylonitrile (PAN) fiber, which is preferably in an oxidized state which promotes subsequent carbonization, especially when CVD is to be used. Green fiber materials PAN fibers and carbon fibers or graphite fibers have also been found to be suitable. Oxidized PAN fibers (hereinafter referred to as "OPF") are available in various forms, such as
It is commercially available in the form of tows, threads, wovens, nonwovens, knitted fabrics and felts. For the purposes of this invention, the preferred starting form is OPF tow, preferably about 6k.
In the range of about 24k, with 12k being suitable for most aircraft friction disk applications. Suitable 12k tows are available from Zoltek (Bridgeton, Missouri) and RKT (Muri of Ord, Scotland). Tows and / or yarns of PAN fibers, carbon fibers, graphite fibers, ceramic fibers, carbon fiber precursors and ceramic fiber precursors, and mixtures thereof can be used.
As used herein, the term "tow" is used to refer to a continuous strand of continuous filament. As used herein, the term "yarn" is used to refer to continuous fibers or staple fibers or blends thereof; thus, the term "yarn" includes tows.
Continuous fibers are generally preferred because of the enhanced mechanical properties in the resulting composite product.

Certain known methods for making carbon fiber reinforced friction discs, such as brake discs used in aircraft (US Pat. No. 3,65 to Carlson et al.
7,061 and U.S. Pat. No. 4,79 to Orly
No. 0,052), the rings are cut from parallel sided sheets of PAN fiber material to form one or more support rings. If the parallel sided PAN sheet material is not thick enough, two or more such rings are stacked and joined by needle punching to form a friction disc support or preform. This procedure produces considerable waste from expensive PAN or OPF sheets, and the cutting waste material cannot be reworked into the form of continuous filaments to make new continuous filament sheets.

Lawton et al., US Pat. No. 4,955,12
3, US Pat. No. 5,081,754, US Pat. No. 5,113,568 and US Pat. No. 5,184,3.
According to No. 87, the amount of cutting waste to be used in the production of discs for aircraft braking systems is reduced by the production of a filament structure shaped in the following way: by needle punching a unidirectional layer of filaments. Provide some degree of dimensional stability; cut multiple segments from a unidirectional layer of needlepunched material; assemble multiple such segments in side-by-side adjacent relationship to obtain the required structural shape Producing at least one similar layer on the first layer; and needle-punching the overlaid layers to assemble and join the segments.
According to Lawton et al., Waste of textile material is reduced.
This is because it is possible to lay down the shaped article of the segment to allow maximum use of the fibrous material. Nevertheless, this approach produces cutting waste material.
This is because the segment must be cut from the sheet in various orientations with respect to the toe direction.

Known methods of recirculating cutting waste PAN sheet waste material (eg, British Patent No. 2 012 671).
The method described in US Pat. No. A, this patent shows that a PAN sheet is chopped into staple fibers and then layer needle punched of carded (recirculated) staple fibers to be transverse to the average direction of the carded staple fibers. Describes a method of forming a new fabric sheet by arranging a reshaped sheet material from this by arranging a substantially unidirectional array of unidirectionally extending continuous filaments and recirculating the sawdust fabric sheet material. Exists), but PA
It would still be desirable to utilize a method of converting N or OPF tows into a near net shaped friction disc that minimizes or eliminates such cutting waste material.

US Pat. No. 5,217,770, entitled "Blade-Shaped Filamentous Structure and Method of Manufacture" to Morris and Lieu, which is incorporated herein by reference, incorporates a stacked layer of blade fiber material into a needle. While describing the efficient production of friction discs and fiber preforms therefor by punching, greater flexibility in the production of friction discs and fiber preforms is still desired.

The purpose of certain aspects of the present invention is to minimize the fiber material of the cutting waste when forming the fiber preforms used in the manufacture of friction disks.
Another object of certain aspects of the present invention is to provide a preform for an annular friction disc that is near net shaped. Another object of certain embodiments of the present invention is to provide a needle-punched structure that provides improved mechanical properties as compared to certain known structures.

Yet another object of certain aspects of the invention is to
It is to provide a needle punched annular structure that is circumferentially continuous and circumferentially homogeneous. Yet another object of certain aspects of the invention is to provide an annular needle-punched structure that is radially anisotropic. According to one aspect of the invention,
Forming a flat stack of layers of fibrous material stacked on top of each other, each layer having a width generally corresponding to the width of the fibrous structure to be formed; Forming at least one of said layers in at least two laterally adjacent portions; and needle punching the stacked layers to displace them out of the layers and in a direction generally perpendicular to the plane of the layers. Provided is a method of making a near-net shaped multi-layer fibrous structure having a width and a thickness, comprising the step of creating cross-links of a layer with fibers extending in the direction of.

According to another aspect of the invention, it consists of a flat stack of layers of fibrous material stacked on top of each other, each layer having a width generally corresponding to the width of the fibrous structure; at least two parallel layers of said layers. Formed of laterally adjacent fiber tapes, each width being less than the width of the fiber structure; forming at least one of said layers of at least two adjacent portions of the fiber tape; and by needle punching A shaped fibrous structure having a width and thickness that are joined to create a bridge of layers by fibers that are displaced out of the layer and extending in a direction generally perpendicular to the plane of the layer. Will be provided.

Producing suitable preforms from various fiber tapes, including braids, knits, woven and non-woven fabrics, the layers being needlepunched so that they can be stacked on top of one another or coiled. I believe you can do it. Referring to FIG. 1, the friction disc 10 is
A preform, such as a blade-curved tape, derived from a tow of OPFs cross-linked to each other by needle punching to consolidate or densify the preform shown in FIG. 11, the OPF being converted to carbon fiber. And further densified after needle punching the carbon matrix deposited using conventional CVI methods. In other embodiments, the crosslinked layer has a matrix of carbon, ceramics, precursors of carbon, precursors of ceramics, and mixtures thereof deposited thereon to further bond the crosslinked layers together. Can have.

Preformed disc 100 shown in FIG.
Due to the blade structure of the friction disc 10 formed from, each of the tows within the disc 10 are substantially continuous (the inner and outer cylindrical peripheral surfaces 1 of the disc 10).
4, 16 or its parallel parallel wear surfaces 17, 18 exclude continuity to the extent that each tow is cut) and other tow members forming blades in a periodic manner The disc 10 is formed from the tow as it passes through the top and bottom and from the outer perimeter 173 to the inner perimeter 172 of the one or more blades 102, 103, as the tow extends circumferentially around the disc.
Continuous fibers are generally preferred over discontinuous fibers because of their higher mechanical properties in the resulting composite friction disc product.

Two or more spirally wound fiber tapes can be arranged to form a flat annulus with a plurality of interleaved fiber layers prior to needle punching. Fiber tape can be formed by collapsing a spiral hollow tubular blade. Between the helical fiber tape formed from the flattened, partially overlapping blades 76, as shown in phantom in FIG. The spiral rotation 71 of the additional blade 72 can be inserted. The additional spiral fiber tape can be formed from a plurality of fiber tapes, including but not limited to side-by-side partially overlapping blades.

As shown in FIG. 2, the volume of fiber, ie, the amount of fiber usually expressed as a percentage / unit volume (0
% Means the absence of fibres, and 100% means the presence of fibres only), which is located adjacent to the inner perimeter 14 of the disc 10 and to the region 20 located adjacent to the outer perimeter 16 of the disc 10. In area 22, disk 1
Greater than the rest of zero. This variation in fiber volume is a natural result of the formation of an otherwise uniformly straight tubular blade, such as the blade 50 shown in FIG. 5, into a flattened annulus.

When the straight tubular blade 50 is flattened to form the flattening blade 60 shown in FIG. 6, it is a double thickness strip of fabric as shown in FIG. 7 and folded back. Regions 62, 63 occur uniquely at the edges 66, 67 extending in the lengthwise direction of the planarizing blade 60, respectively. Each such folded area 6
2, 63 are each such folded edges 6
It has a higher fiber volume in the central region 64 between 6, 67. Also, a straight blade, such as blade 5
When the 0 and flattening blades 60 curve into the annulus or its arcuate portions, the blade-forming members are closely abutted together adjacent the inner periphery of the annulus and adjacent the outer periphery of the annulus with respect to the central region of the annulus. Be separated. This naturally occurring fiber volume variation in curved blade tapes can be minimized by the blade technique described below. Alternatively, the pre-determined bias in fiber volume is advantageously used to provide additional fiber reinforcement to drive the lugs to be formed on the outer or inner periphery by machining of the resulting densified friction disc. You can The central region 24 is located between the regions 20 and 22 of the disc 10 and is higher in fiber than the region 23 which forms the remainder of the disc 10 due to the overlapping of the two parallel fed blades which formed the disc 10. Has a volume.

In certain preferred embodiments, in addition to the blade members extending in a helical path with respect to the length of the blade, a longitudinal system is introduced therein as the blade is formed. These longitudinal members may be referred to as "unidirectional members". These one direction increases dimensional stability and tensile strength, compressive strength and modulus, and fiber volume of the blade fabric. The unidirectional member is introduced from the stationary guide eye on the braiding machine so that it lies in a straight line (without crimping) parallel to the blade axis (longitudinal direction of the blade), but by the carrier of the braiding machine. The introduced helical blade members pass above and below them as the blade fabric is formed.

Referring to FIG. 7, the flattening blade 60 includes a unidirectional member 54, the unidirectional member 54 increasing in size from a folded region 62 to a folded region 63. Changes to the ID of the ring
When a uniform straight tubular blade is flattened and curved to form an annulus with a region 62 adjacent the (inner diameter) and a region 63 adjacent the OD (outer diameter) of the annulus,
Otherwise, it compensates for the inherent fiber volume bias. A smooth progression of size is shown in FIG. 7, but also when all of the unidirectional members are of the same size, but when the tubular braid is being formed, the unidirectional members are inserted into the tubular braid. It is within the scope of the invention that when introduced, their spacing changes in a predetermined manner. Figure 7
As shown in B, the unidirectional members 54 ′ of the flattening tubular braid 60 are spaced from each other in a manner that varies from the inner lip 66 towards the outer lip 67 ′, with the outer lip 67 being the inner lip. When approaching in the direction of the lip 66, the unidirectional members 54 'are positioned progressively closer together. Also, the size in the array of unidirectional members,
Simultaneous changes in spacing, tension and materials are within the scope of the invention. The unidirectional member can be a different material than the member introduced by the carrier of the braiding machine.

Referring to FIGS. 11 and 12A, FIG.
And the manufacture of the preform 100 using when making the friction disc 10 shown in FIG. 2 is shown. Each of the flattening precuring blades 102, 103 is formed from a tow 12 and is sized in a predetermined manner between the spaced apart first and second ear portions 156, 157. Includes a unidirectional member 154 that changes in angle. In the particular embodiment illustrated in FIG. 12A, the unidirectional member 154 has a gradual increase in size from the folded region 162 to 163, which results in a ring ID.
When the uniform straight tubular blade 102 is flattened and curved to form an annulus having a region 162 adjacent the (inner diameter) periphery and a region 163 adjacent the OD (outer diameter) periphery of the annulus, so Otherwise, it offsets the inherent fiber volume bias. In a similar manner, the flattening blade 103 includes a unidirectional member 154, which is folded back region 172 to folded back region 173.
Toward the ring OD and the region 172 adjacent to the ring ID (inner diameter) periphery.
When the uniform straight tubular blade 103 is flattened and curved to form an annulus with adjacent regions 173 around the (outer diameter), it compensates for the otherwise inherent fiber volume bias. . Since regions 163 and 172 of each 102, 103 overlap, these regions in certain preferred embodiments contain less unidirectional fiber contribution and to avoid excessive fiber volume, and of zero. A unidirectional member can be included.

As shown in FIG. 12A, the unidirectional member 154.
Increases in size from around the ID of each blade to around the OD. As shown in FIG. 12B, the unidirectional members in the overlapping regions 163 'and 172' are smaller than those in the central portion 164 'adjacent to them.

As shown in FIG. 12C, the unidirectional member 154.
Are all of equal size but are unequal spaced from each other, thus varying the fiber volume in a predetermined manner. As shown in FIG. 12D, the unidirectional member 1
54 are of equal size and are concentrated at locations corresponding to the ID and OD perimeters of the finished preform and friction disc. This configuration of the tape layer results in a fiber volume and a resulting volume in the notched region to be formed in the inner or outer perimeter of the friction disc, which is prepared to engage a corresponding spline or drive lug for torque transmission. It can be used to enhance mechanical properties.

As shown in FIG. 12E, the unidirectional member 154.
Are of equal size but are unequally spaced from each other, thus varying the fiber volume in a predetermined manner. This configuration of tape layers can be formed from two blade tapes that are identical, but each has a different radius of curvature. Referring to FIGS. 12A, 12B, 12D and 12E, the unidirectional members 154 of each of the collapsed tubular braids are intentionally laterally offset with respect to those of the corresponding lower layers and contribute to the unidirectional members. Better distributes the fibers being made and promotes needle punching. This is in contrast to Figure 12C, where the unidirectional members are vertically aligned in the upper and lower layers of the tubular blade.

12A, 12B, 12D and 1
As shown in each of 2E, the two associated overlapping blade members are of the same configuration with a smaller number of unidirectional members / unit width adjacent their ID perimeters than their OD perimeters. For each of these configurations, it is necessary to manufacture the only type of blade prior to forming the preform. In contrast, the configuration shown in Figure 12D requires the production of two blades of different configurations.

The unidirectional member size progression is shown in FIGS. 12A and 12B, but also as shown in FIGS. 12C, 12D and 12E, although all of the unidirectional members are of the same size. It is within the scope of the invention that the spacing of the unidirectional members may change in a predetermined manner when the unidirectional members are introduced into the blade when the blade is formed in. As shown in FIG. 20, the unidirectional member 203 is placed asymmetrically within the creel 190 (shown in FIG. 16) around the axial midline 186 of the braiding machine to provide a blade, such as the blade shown in FIG. 12E. 103 can be manufactured. This is the preferred approach as it avoids the need and expense of manufacturing and storing unidirectional members of varying sizes. Array size, spacing of unidirectional members,
Simultaneous changes in tension and material are within the scope of the invention. Some or all of the unidirectional members can be made from different materials of the members introduced by the carrier of the braiding machine. The unidirectional member of a different material than that used for the remainder of the member that forms the blade facilitates needle punched and densified structure fabrication and beneficial final mechanical or other properties. be able to. Such materials for unidirectional members could include other carbon-based and / or ceramic-based fibers.

In the embodiment shown in FIGS. 11 and 12,
The preform disc 100 comprises a flattened, partially overlapping blade 102 formed from an OPF tow 12 which is then needle punched together.
It comprises one or more spiral rotors 101 symmetrical about an axis 99 of 103. The laterally adjacent ears 156, 157 of the blades 102, 103 are overlapped. When finished, the preformed disc 100 looks similar to that of the friction disc 10 illustrated in FIG. In a manner similar to that illustrated in FIG. 8, one or more additional spirally wound fiber tapes (FIG. 11).
Parallel blades 102, 103 (not shown in FIG.
Can be inserted to form a flat annulus with multiple layers of fibers interleaved prior to needle punching.
Each tape can be formed by collapsing a spiral tubular blade.

In the embodiment shown in FIGS. 13 and 14,
The preform disc 120 comprises a plurality of flattened, partially overlapping blades 1 formed from an OPF tow 12 which is then needle punched together.
Axis 1 of 23, 124, 125, 126, 127, 128
One or more spiral rotors 12 symmetrical about 22
Consists of one. Each blade tape can be formed by collapsing a spiral tubular blade. When finished, the friction disc resulting from the preformed disc 120 is similar in appearance to that of the friction disc 10 illustrated in FIG. In a method similar to that illustrated in FIG.
Parallel blades 12 between one or more additional spirally wound fiber tapes (not shown in FIG. 11).
3,124,125,126,127,128 can be interleaved to form a flat annulus with multiple fiber layers interleaved prior to needle punching. Relative humidity tape can be formed by collapsing a spiral tubular blade.

The disk 120 shown in FIGS. 13 and 14.
Individual blades 123, 12 used in the manufacture of
The width of 4, 125, 126, 127, 128 and hence the radial extension is I in the shape of the flat arc formed.
Relatively small compared to the radial distance between the D perimeter and the OD perimeter, from the ID perimeter of any individual blade to the OD
The amount of fiber volume variation to the perimeter is naturally about 5 to about 7 inches for a typical large commercial aircraft brake friction disk when a single curved blade spans the same radial amount. Small compared to the fluctuations that occur.
For this reason, the individual blades 123-128 need not include unidirectional members arranged to compensate for such changes in relative unit fiber volume due to the induced curvature. However, the inclusion of unidirectional members is recommended to enhance the stability of the individual blades 123-128. These small blades, about 1,25 to about 2 inches wide, can be formed on a conventional tubular braiding machine with 48 or more carriers, or on a conventional flat braiding machine.

12A-12E and 14 are intentionally distorted for clarity of illustration, and in actual practice the individual blades sag in each overlap region, and, in addition, needles It should be understood that punching will also follow, and that there will be no gaps between or within the vertically stacked layers.

Referring to FIGS. 11, 12, 13 and 14, an annular shape utilizing a plurality of blades each having a width less than the radial distance from the ID periphery to the OD periphery of the formed ring. You can make preforms. Radially adjacent curved ear portions of the blade portion are partially overlapped prior to needle punching. Such radial overlap is believed to improve the mechanical properties of the needled preform disc and the friction disc made therefrom. It is believed that the amount of radial overlap preferably ranges from about 10% to about 25% of the radial extension of the individual blades used in forming the annular preform. In order to avoid excessive unit fiber volume in the overlapped area, the unit fiber volume in the edge region of the blade is
It can be reduced with respect to that of the rest of the blade as shown in FIG. Such smaller blades can be manufactured on a braiding machine having slightly less carrier than the 144 carrier braiding machine previously described for use in manufacturing a single radial span blade. For example, a 72 carrier braiding machine can be used to produce a tubular braid having a circumference of 4 inches, which corresponds to a flattening width of about 2 inches.

Referring to FIG. 21, another embodiment of a preform 280 comprising a stack of layers of fibrous material is shown in cross section. Each of layers 281, 282 is preform 2
It has a width generally corresponding to a width of 80. The lower layer 282 is
It is formed from two laterally adjacent (side-by-side contact) fiber tape portions 283 having contacting ears. Preforms of greater thickness can be made by repeating the illustrated pattern when they are joined by needle punching when successive layers are stacked to a desired height.

In FIG. 22, another embodiment of a preform 290 consisting of a plurality of vertically stacked layers of fibrous material is shown in cross section. Each of the layers 291, 292 has a width that generally corresponds to the width of the preform 290. Each of the layers 291, 292 is formed from a plurality (three illustrated) of laterally adjacent (side-by-side contact) fiber tape portions 283 having contacting ears. The layers 292 are laterally offset with respect to the immediate preceding and immediate successive layers 291 so that the contacting ears of the fiber tape 283 are not vertically aligned. Preforms of greater thickness can be made by stacking layers 291 and 292 sequentially in an alternating manner.

23 and 24, an annular preform disk 300 of a single spirally wound fiber tape 301 is shown in plan and cross-sectional views, respectively. Each layer 302, 303 is a fiber tape 301
Is formed by spirally winding. Textile tape 3
The layers 303 are laterally offset with respect to the immediate preceding and successive layers 302 so that the contact ears of 01 consecutive rotations are not aligned in the direction of the stack height corresponding to the thickness of the preformed disc 300. The preforms of greater thickness have layers 302 and 30 in an alternating manner.
It can be made by stacking 3 in sequence.

Referring to FIG. 24, there is shown in cross section a preform 310 consisting of a stack of layers 311 each formed from laterally adjacent fiber tape 283 having ears in contact. Preform 310 is not a preferred embodiment because fiber tape 283 is aligned through the thickness of the preform, resulting in low resistance to shear loading.

In all embodiments where the fiber layers are two or more laterally adjacent fiber tape sections, overlapping or contacting ears of the tape sections must be sewn together prior to needle punching the stacked layers. You can For example, the tape portions 283 forming any of the layers 291, 292 shown in FIG. 22 can be joined by stitches 284; layers 302, 30 shown in FIG.
The tape portion 301 forming one of 3 is stitch 2
It can be joined by 84. Pre-sewn allows the handling of multiple laterally adjacent tape sections as if they were a single tape section of greater width or, if curved, of greater width. Pre-stitching of spirally wound fiber tape with contacting ears prevents separation of laterally contacting rotors during needle punching.

Manufacture of Blade Tape A plurality of tows 12 are loaded onto a conventional braiding machine (not shown). A simplified version of a conventional Maypole type braiding machine and its operation is illustrated in US Pat. No. 3,007,497 to Shobart. Primarily suitable braiding machines are available from Steeper, Wuppertal, Germany. In operation of this stapler device, the blade material is pulled through the inside of the forming ring rather than being pulled out of the outside of the mandrel. The tow 12 should be tightly wound into a uniform package for use as a blade. Due to the annular shape, i.e. the curved nature of the brake disc to be formed, e.g. the friction disc 10, a tow count and correspondingly deviation of the quantity / unit area of the fiber is inherent and the fiber volume is It is largest at the inner perimeter 14 and at least the outer perimeter 16 of the 10. The term "count", as used herein with reference to a tow or yarn forming a fibrous element, such as a fabric, means the number of fibrous elements / linear inches measured perpendicular to the machine direction of the fibrous element. . Blade angle of tow is 30-50
Can be in the region of °, and the number of blade carriers to be used, the desired fiber volume, the dimensions of the friction disc to be formed, and the forming tubular before flattening and bending into the shape of the friction disc thus formed. It is believed to vary based on blade size and diameter.

Another way to characterize the blade is by books / inch (PPI). Formed from 12k tow and 1
For a curved blade having a nominal ID of 0 inches and an OD of about 20 inches, preferably the ID of the curved blade has about 5 ppi;
D has about 2.5 ppi. PPI is the speed of the braiding machine,
It is a complex function of the draw speed of the fibrous material, the angle of draw and the width of the blade, and is determined experimentally. 5
PPI means that five interlaces of the bladed member occur per inch of machine direction movement. When the braiding machine is adjusted experimentally, the PPI can conveniently be determined manually.

As used herein, the term "blade angle" and related forms means the acute angle defined by the tangent to the helix with respect to the longitudinal axis of the tubular blade being formed. As shown in FIG. 5, the tow 12 formed tubular blade 50 is symmetrical about its longitudinal direction or about the blade axis 53. As shown in FIG. 6, the tubular blade 50 has a blade angle α of 40 °. The pattern of blades measured along the blade axis 53 is called a "plate". For a given blade member (eg, 12 k OPF tow), the plate spacing determines the angle 2α between the members of the blades of two opposing spiral orientations. For tubular blades with r blade iterations and blade winding lengths per s blade circumference, the following relationship can be established: α = tan −1 (s / r) which is the helix angle Of the standard, where the repeat length is equal to the cycle length of the helix. For a plurality of blade tapes, each of which is a similar flattened tubular blade tape 60 shown in FIGS. 6 and 7A or a tape 60 ′ shown in FIG. 7B, each producing a width corresponding to a portion of the fibrous structure to be formed. To be done. The tape can be curved to correspond to the desired preform shape. When it is desired to produce a friction disc, the tape is formed into an annulus by curving the tape around a circular central guide or mold, such as the central mold 9 shown in FIG. Can be passed. Alternatively,
The tape can be fed to a rotary needle loom as shown in FIGS. 11, 13 and 15. In this case, each blade tape has a width less than the radial distance between the ID perimeter and the OD perimeter of the annulus.

The curvature of the linear blade containing the unidirectional member not only affects the fiber volume, but also
And creates a convolution due to the difference in tension between the OD and unidirectional members. These non-uniformities include bunching, span width shrinkage and other related distortions. For these reasons, making the blade as a curved blade is preferred, especially when the blade width is greater than about 25% of the radius at which the blade should be curved.

Manufacture of Curved Blade Tapes Curved blades are more precisely formed mechanically rather than manually, as described in US Pat. No. 5,217,770 to Morris et al. You can Suitable apparatus for the manufacture of curved or spiral blades is shown in Figures 16-20.

Referring to FIG. 16, a curved blade forming apparatus 200 is shown. Braiding machine 180 and unidirectional member 203 to be formed on curved blade 201
The creel 190, which contains a package of, is conventional in design and operation. Applicants have used 144 carrier braiding machines that allow 72 additional unidirectional positions to be evenly spaced around the circumference of the braiding machine, although the present invention is much larger. Alternatively, it is believed to be effective using a braiding machine with a small number of carriers and unidirectional positions.

The apparatus 200 for forming the curved or spiral blade 201 comprises a forming ring 210 through which the fibrous material 202, 203 braided, is drawn from the braiding machine 180 and the creel 190 into the drawing device 22.
0 draws into the nip 224 of a pair of juxtaposed frustoconical rolls 222 that are driven synchronously. The frustoconical rolls 222 are preferably the same. Gap or nip 224 between juxtaposed frustoconical rolls 222
Means 230 are provided for adjusting the pressure and exerting a predetermined amount of pressure on the blade 201 passing between the side-by-side frustoconical rolls 222. The frustoconical roll 222 is driven synchronously by a single worm gear 226,
The teeth of worm gear 226 mesh with complementary teeth 227 that surround the large proximal end surface of each frustoconical roll 222. The multi-centered curve chute 240 provided at the output of the nip of the frustoconical roll 222 causes the curved blade 201
Guides the curved blade 201 as it forms the winding package 256. The apparatus 200 includes a rotatable take-up device 250 which, in certain preferred embodiments, is synchronized with the speed of the frustoconical take-up roll 222 and the speed of the braiding machine 180. In its simplified form, the take-up device 250 consists of a motorized vertical screw 251 whose pitch corresponds to the thickness of the flattened curved blade 201 to be formed. The lower flanged bobbin 256 mounted on 250 is lowered by an amount corresponding to the thickness of the blade 201 wound thereon upon rotation.

As shown in FIG. 16, the plane of forming ring 210 and the plane within axis 223 about which each frustoconical roll 222 rotates are parallel and with respect to the axial midline 186 of braiding machine 180. Located at a common angle α. Further, the take-up roll device 220 is the braiding machine 1
It is laterally offset with respect to the midline 180 of 80. FIG.
The angle α is about 20 ° as seen at 6, and the offset is toward the right edge of the braiding machine 180 when viewed from the winder 250. The nip 224 of the frustoconical roll 222 is located on the vertical midline with respect to the vertical center of the braiding machine 180. The curved braid device 200 further includes a multi-centered curve chute 240, which facilitates transport of the formed curved blade 201 into a motor driven winder 250. As seen in FIG. 18, the take-up device 250 includes a motorized screw 251, which is synchronously driven by a motor 252 through electrical interconnections (not shown) in a known manner, and the motor 229 is The frustoconical take-off roll 222 is driven and one or more motors 189 drive the braiding machine 180. Screw 251
Are rotatably adapted through stationary nuts 259 fixed to the subframe 260. When the screw 251 is ortho with respect to the nut 259, it lowers the bobbin 256 on which the curved blade 201 is wound. The upper part of the screw 251 is the flange member 2
53, the flange member 253 has a vertically projecting pin 254, on which the upper blade bobbin 2 on which the curved blade 201 is wound.
Mates with complementary openings formed in the lower flange 255 of 56. The flange member 253 also includes the bobbin 25.
A central hub 25 protruding from the bottom of the flange 255 of No. 6
It has a central groove 257 that receives 8. The engagement of the hub 258 with the groove 257 centers the bobbin 256 on the flange member 253.

The frustoconical take-off rolls 222 can be the same. They can be formed from cast iron forming a machined frusto-conical surface. The included angle of the truncated right circular cone of each frustoconical roll 222 is US Pat. No. 4,018,482, US Pat. No. 4,878,563.
And a pre-cured blade material suitable for use in the manufacture of friction discs for use in multi-disc brakes similar to those shown and described in U.S. Pat. No. 4,613,017, preferably about 6
It is 0 to about 90 °. Increasing the included angle will increase the difference in surface velocity between adjacent points along the contact line of the frustoconical take-off roll 222. This contact area with the material to be bladed can also be referred to as the nip 224 of the juxtaposed frustoconical rolls 222. Each frustoconical roll 22
The larger included angle in 2 results in a larger difference in surface velocities between the tip of the cone and the base of the cone, thus the radius of the curved blade 201 becomes shorter when the other factors are equal. However, the 90 ° included angle of each frustoconical roll 222 provides a desired range of pre-cured blades for use in the manufacture of aircraft friction discs having an outer diameter of about 24 inches and an inner diameter of about 10 inches. Was found to be sufficient, and it was not found that multiple sets of different frustoconical take-up rolls were needed for the desired range of curved blades. The size of the take-off roll must be sufficient to represent the line of contact between them, ie at least as long as the width of the flattening blade. The width of the blade extends along the length of the blade and can be defined as the distance between laterally spaced first and second edges. This dimension ha is about 4 to about 8 for a typical commercial aircraft brake disc formed by spirally winding and needlepunching a single curved blade spanning the entire radial distance of the preform. Can be inches. A number of narrower curved blades are utilized as in the present invention, but this dimension is smaller, typically no more than about 2 to about 4 inches. For the embodiment shown in FIGS. 13 and 14, this dimension would be about 2 inches.

Each frustoconical take-up roll 222 is supported about an axis 223 congruent with the axis of symmetry of the respective frustoconical roll. The longitudinal axes of the pair of axes 223 lie in a common vertical plane and are such that they intersect at an angle such that the facing surfaces of the frustoconical rolls 222 form parallel horizontal nips 224 or contact lines. Located in. Around the base of each frustoconical roll 222 has teeth 227 complementary to the teeth of the worm gear 226 driven by the motor 229. Thus, the frustoconical take-up roll 22
The two are driven synchronously at corresponding facing locations along the nip 224 at the same rotational speed and substantially the same surface speed, thus their facing surfaces in contact with the fibrous materials 202, 203 are nominally They have the same surface speed.

The lower take-off roll 222 can be moved to adjust the gap or nip 224 between the lower and upper frustoconical take-up rolls 222. As shown in FIGS. 17 and 18, the lower frustum-shaped pull roll 2
A shaft 223 carrying 22 is placed on the reciprocating means 230 to move it from and in the direction of the upper frustum pulling roll 222. The reciprocating means 230 is the frame 2
31 and the lower frustum-shaped pull roll 222 to move relative to the direction of the upper frustum-shaped pull roll 222,
It has a movable frame 231 which is connected to the hydraulic jack 232 shown or to a pneumatic load cylinder not shown.

The method of adjusting the nip 224 is preferably
The lower frustum-shaped pulling roll 222 has teeth 227 of the lower frustum-shaped pulling roll 222 and the worm drive gear 226.
The method is such that it is movable along a straight path, which is almost always in deep mesh with the teeth of. The forming ring 210 is disposed between the frustum pull roll 222 and the braider 180. The forming ring 210 may be made of an aluminum material. The entrance side of the center hole of the forming ring 210 extends toward the braider 180 or is rounded (r
abraded) and is ground to minimize friction on the fibrous members 202, 203 dragged thereon during the braiding operation. Forming ring 2
10 is a frustum-shaped pulling roll 222 and a braider 180.
It is firmly installed against. This includes forming ring 210 with a frame 244 on which a frustum-shaped pull roll device 220 and a take-up device 250 are mounted.
It can be easily done by connecting to a subframe that is firmly attached to. The preferred inner diameter of the forming ring 210 must be determined empirically. If it is desired to form a wide flat bent braid, a larger inner diameter forming ring is preferably employed,
In the opposite case, the opposite is true.

As can be seen in FIG. 16, the machine frame 244 is inclined with respect to the axial centerline 186 of the braider 180. The nominal tilt angle is about 20 ° for the above-described curved braid formation. Increasing this angle will reduce the roundness of the curved braid to be formed, and conversely will increase the roundness of the curved braid to be formed.
Increasing the distance between the forming ring 210 and the braider 180 will increase the number of intersections of the members 202, 203 that are picked or braided per inch. Conversely, reducing the distance between the forming ring 210 and the braider 180 reduces the number of picks per inch of the member being braided. Increasing the number of picks per inch necessarily reverses as the braid angle increases and vice versa, leaving all other factors unchanged.

The use of the curved braiding device 182 described above is described below. All of the 144 carriers 182 of the braider 180 were filled with the fibrous material to be braided, eg, oxidized PAN tow member 202. The selection position of the braider was made from the creel 190 to the unidirectional 203. As illustrated in FIG. 20, a number of unidirectional 203 are provided with braiders spaced about the greater curved perimeter or contour of the flat, curved braid 201 to be formed. Supply to 180. The position unidirectional 203 may be overlapped in a position corresponding to near the large curved perimeter of the curved braid 201 to provide a curved braid 201 having the desired fiber volume. These Unidirectional 203
It helps to stabilize the winding of the braid 201 and the subsequent processing. All of the members 202, 203 to be braided are manually pulled through the forming ring 210 and nip 224 of the frustrated conical pull roll 222. The lower pull roll 222 is then raised in the direction of the upper pull roll 222 and the nip 224.
Of the fiber member 202 at the nip,
Pressurize 203. The entire machine is then driven to initiate actuation of the braider 180 and synchronous actuation of the pull roll 222. As the braided material 201 extends near the rear of the nip 224 of the frustum pull roll 222, the non-braided fibrous material is also trimmed. Bent flat chewable braid 2
01 slides down the chute 240 and is helically wound up on the take-up bobbin 256. When the take-up bobbin 256 is full, the braiding operation is stopped, the bent braid is cut off, and the full bobbin 2
56 is removed from the take-up device 250. The screw 251 of the take-up device 250 returns to the full height at the original position, and the empty bobbin 256 projects upward from the flange 253 of the take-up device 250. The drive pin 254 has a bottom flange 255 of the top hat bobbin 256. It is mounted so as to be engaged with the complementary hole therein.
Thus, the braiding operation begins again. The holes are
Top hat bobbin 25 on take-up device 250
Bent braid 20 during centering and forming 6
It acts to give a drive torque to the take-up of 1.
The curved blade device can be modified from that described above. An example of such a change is as follows. Forming ring 210
Angle and the frusto-conical pull roll mechanism 220 to the centerline 186 of the braider 180 should be reduced when it is necessary to provide a curved blade 201 with a larger radius of curvature. Applicants have found that the 20 ° angle described and described herein was suitable for making curved flat tubular braids having an inside diameter of about 10 inches and an outside diameter of about 24 inches. Braider 180 and frustoconical pull roll 222
The forming ring 210 located between and is unbraided as it is drawn from the braider carrier 182 and filamentary package 192 creel 190 to a common forming or converting point at or near the nip 224 of the forming roll 222. The members 202 and 203 of the above are oriented.

For flexibility and convenience of operation of the control system, it is preferred that the control system include electronically interconnected drive motors. The drive motor 189 (single or plural) of the braider 180 uses a first potentiometer (not shown) to move the truncated cone-shaped pull roll 22.
The second motor 229 uses a second potentiometer (not shown) to rotate the top hat bobbin 256.
The motor 252 of 50 can be controlled by a third potentiometer (not shown). After the desired blade speed is obtained by the relative adjustment of the speeds of the various drive motors 189, 229 and 252, the master speed controller (not shown) is controlled upward or downward to affect the characteristics of the blade during molding. Increase or decrease the overall speed of the curved braid product without. Further, each motor can be operated at a low speed for easy loading, doffing and maintenance to the device. Pull roller 22
The number of crossovers or picks per inch can be increased by increasing the braider speed for a speed of 2. Conversely, lowering the braider speed relative to the pull roll speed can reduce the number of crossovers or picks per inch. Since the blade 201 is curved, the number of picks per inch will always change between the inner and outer diameters of the blade 201, and the outer diameter will always reduce picks per inch. , Curve is inversely proportional to both. Conversely, straight, flattened tubular braids have the same number of picks per inch at each periphery.

The frusto-conical pull roll 222 does not require any special treatment when it is formed from milled iron casting. The use of an elastomeric coating or cover on the frustoconical pull roll 222 is not necessary or recommended as the relatively high pressure at the nip 224 can cause misalignment and tearing of the cover. It is possible to obtain a sufficient frictional pulling force only by squeezing the blade 201 between the truncated cone rollers 222.

Example 1 (Formation of curved braid) A curved braid having an inner radius of about 13 cm (5 inches) and an outer radius of about 30 cm (12 inches) was determined to be experimentally suitable. It was manufactured by adopting the following setting parameters. It has been found suitable for the forming ring to have an inner diameter or opening of about 29 centimeters (11.5 inches), which corresponds to about twice the width of the flattened curved blade to be formed. The ring 210 was located approximately 1.5 meters (56 inches) from the braider 180. Ring 210 was positioned approximately 25 centimeters (10 inches) from pull roll nip 224. The forming ring 210 and the vertical plane defined by the pull roll axis 223 were bent at about 20 ° with respect to the axial centerline 186 of the braider 180.
The opening is equipped with a frustoconical pull roll, and each pull roll has 9
It had an included angle of 0 °.

Formation of Annular Preforms One or more layers of flattened tubular braid are joined together by needle punching and / or one or more other fibrous layers are laminated thereon.
To this end, the stacked layers are molded or jig 90
Such a jig is passed through a conventional needle punch room (not shown, such as the needle punch room disclosed in US Patent No. 2,930,100 of EC Rust, Jr).

As a preferred alternative, needling of the braid into a single preform structure is performed as the braid is continuously fed to the rotating support. Preferably, this is done by using a rotating needle punch room such as rotating room 30. A part of this loom is shown diagrammatically in FIG. Other features of this loom are shown in FIG. The loom 30 includes a rotary crank 31, a connecting rod 32, a reciprocating platen 33, a needle board 34, a needle 35, a stripper plate 37, and a rotary bed plate 38.
The rotation of the crank 31 causes the platen 33 to reciprocate, causing the needle 35 of the needle board 34 to reciprocate back and forth with respect to the bed plate 38 through the stripper plate 37. The fiber layers to be joined to each other are passed between the stripper plate 37 and the bed plate,
On the other hand, the reciprocating motion of the needle board 34 causes the needle 35 to penetrate the fiber layer. Needle 35 herb (har
b) 36 interconnects the layers by withdrawing the fibers / filaments from the layers in a direction generally orthogonal to the plane of the layer. The bed plate 38 directs the rotation of the fibrous layer through the working area of the reciprocating needle to a bristle brush.
rush) 29. Further, it is provided to adjust the distance between the bottom end of the stroke of the needle and the bed plate 38. To do this, the stroke of the needle is changed, the entire drive mechanism for the needle is raised relative to the bed plate, the bed plate is lowered relative to the needle drive mechanism, or any suitable combination of these means. I do. The fibrous tape introduced into the rotary needle loom is guided and held in that position by the conical roll 40. An example of a rotating bed needle loom is Dilo DE
2911762. This loom is slightly modified to introduce the fibrous slit top in a spiral pattern with or without the overlapping of the ears of the fibrous strip. The needling head follows the movement of the fibrous strip and avoids undergoing excessive needling.

The following examples are examples of carbon-carbon friction discs of the present invention and illustrate their preparation in accordance with the present invention. However, the present invention is not limited to the following specific embodiments. Example 2 (annular preform from two curved blades) Curved blade A with a rough inner diameter ID of 10.5 inches and a rough outer diameter OD of 18 inches, a rough inner diameter ID of 16.5 inches and a rough inch of 24 inches. A curved blade B having an outer diameter OD was prepared. The blade A and the blade B are spirally introduced into the rotary needle loom while being overlapped in the radial direction with a length of about 1.5 inches, and joined by a needle punch.

Example 3 (annular preform from two identical braids) A 2x2 curved braid was produced with a conventional tubular braider. Here, the curved blade had a circumference of about 10 inches (a flat width of 5 inches) and a blade angle of 40 ° at the midpoint of the width of the blade. All carrier tensions remained the same during the braiding operation. While the tubular plaid is being molded,
The blade is drawn out from the forming ring, flattened by a truncated cone-shaped pull roll, and wound on a silk hat-shaped bobbin 256 in a continuous spiral tape shape. A pair of braids were unrolled from separate top hat bobbins 256 and continuously fed to an axially rotating needle punch loom in a side-by-side arrangement. Pairs of laterally adjacent blades are partially overlapped as they are fed onto the rotating bed of the loom by an amount of about 25% of the individual blade width. The feed rate of the spiral blades is synchronized with the speed of the rotating support bed of the loom. When the desired thickness of about 2 inches is reached, the feed blade is cut and the finished preform removed. The resulting preform has an OD of about 63.5 cm (25 inches) and an ID of about 25.4 cm (10 inches). It is believed that punching is unnecessary because the resulting preform has a net-like shape.

If a rotary loom is not available, a support jig 90 similar to that shown in FIG. 10 is made and utilized in needle punching an annularly wound layer of fiber tape on a conventional needle loom. The use of jig 90 is less desirable than the use of rotary needle loom. This is because the fiber tape may not be continuously supplied onto the jig 90 when the jig 90 moves back and forth through an ordinary reciprocating loom. Briefly, the jig 90 consists of an annular central mold 91 secured to one of the large flat surfaces 92 of a flat shipping board 93. The transport board 93 can be used to thread a helically wound layer of fiber tape through a conventional needlepunching loom, such as the loom shown in FIG. The central mold 91 prevents the fiber layer from over-distorting during needle punching.

The transport board must provide a dimensionally stable and rigid support as the fibrous layer passes through the needle punch loom. The transport board must have a thickness and composition that allows the needles at the needle punch locations to penetrate them without damaging the thickness and composition. A suitable transport board 93 is a multiple PAN or O
It can be made by needle punching PF tow material or equivalent material together. Approximately 1/2 the total thickness formed from a layer of PAN or OPF tow
A transport board having inches is believed to have the appropriate rigidity and other properties of the shaped structure according to the present invention.

An annular central mold 91 having a diameter slightly smaller than that of the friction disk preform to be manufactured and a thickness of about 3/8 inch is attached to the transport board to complete the needle punching jig. The central mold 91 is made of neoprene elastomer material, PAN or O.
It can be formed from a needle-punched layer of PF tow or equivalent material. The center mold 91 is a suitable adhesive, such as Camie-Campbell, Inc.
Camii (Ca, available from St. Louis, Missouri
Mie 363 Fastac can be attached to the transport board 93. If the central mold 91 is made of fibrous material, it can be attached to the transport board 93 by needle punching. The thickness of the central mold 91 was approximately equal to that of the two-turn body of fiber tape. The integrity of the preform of the friction discs of the manufactured blade was maintained by the jig 90 during needle punching, which prevented excessive straining of the annulus during needle punching. The jig 90 requires the jig 90 for controlled passage of preforms whose feed is manufactured through a conventional needle loom whose mechanism includes rollers powered at its inlet and outlet.

The jig 90 is used as follows. Cut a piece of fiber tape long enough to surround the central mold,
Then lay it on the transport board around the central mold in a circular manner with slight overlap of the tape edges. A slight overlap of the ends of the fibrous tape is first applied to the transport board to ensure that the ends of the tape do not separate during the initial needle punching of the resulting preform structure. As the resulting preform structure passes through a needlepunt loom, movement and deformation may occur, which in part tends to be needlepunched into an oval shape due to elongation in the direction of passage. The use of jig 90 minimizes such unwanted movement and deformation. When the subsequently added annular fiber layers are joined by needle punching, less movement and deformation of the preform structure that occurs occurs.
The ends of the fiber tape are indexed at some point on the central mold or transport board and then passed through a needle punch loom. The stroke of the needle-punch loom is such that the needle partially penetrates the transport board, for example about 1/4 inch, and slightly penetrates the layer of annular fiber tape itself while at the same time making it lightly transport board. Make it sticky. Excessive needling in this process should be avoided. This is because this results in a fiber tape that is firmly bonded to the shipping board that must be subsequently removed from the shipping board. After this first pass of the loom, the jig 90 containing the ring of fibers is 90 ° with reference to the zero indexing position.
It is spun and again passed through the needle loom in the opposite direction using standard needle punching procedures.

Thereafter, a second annular layer of fiber tape is placed on top of the first. The end of this second fiber tape layer is indexed with respect to the end of the first fiber tape layer by 60 ° from the splice area of the first fiber tape layer. The ends of the second annular fiber layer are contacted. It is believed that the overlap of the second and any subsequently added fibrous layers is unnecessary. This is because it is expected that little movement will occur during these needlepunchings. The indexing direction is constant through friction, ensuring the relative relationship of the fiber layers, ie avoiding stacking of their contacting ends. The needle punch loom bed plate is lowered by an amount such that the needles penetrate into the first annular fiber tape but not the transport board beneath the first annular fiber tape. The assembly passes through the needle punch loom several times,
The rotation of the annulus is formed at 90 ° with respect to the transport board before passing through each needle punch weaving machine without the addition of additional fiber material. Use conventional needle punching equipment and procedures.

An additional layer of annular fiber was added once at a time, each having a batt splice indexed at 60 ° from that of the preceding underlying layer. After the addition of each layer of annular fiber, the assembly is passed through a needle punch loom several times with a 90 ° rotation before each pass after the first. As each additional layer of fibrous material is added, the bedplate is lowered to compensate for the added thickness of the preformed disc being formed.

Referring to FIG. 9, after the addition of several layers, for example about 5 or 6 layers, each formed from a flattened tubular blade, the needle punched structure of the blade is It can be observed to have a material thickness profile for the supporting surface 92 on the transport board 93 which is accumulated faster adjacent the ID of each such blade than the OD.
This is due to the inherent slight non-uniformity of the circumferentially uniform tubular blade when the blade is flattened and forced into a straight to annular shape. The overlap of the ears of a plurality of laterally adjacent fiber tapes may exacerbate the build up in the overlapped areas.
To accommodate this non-planar build up, the needle punch loom stripper plate is raised in addition to lowering the bed plate.

FIG. 9 is deliberately exaggerated and fiber volume and outer profile deviations can be minimized or eliminated by careful selection of blade construction, layup and needlepunching procedures. When the desired thickness is reached by the addition of further layers of annular fiber, the preform is flipped up and re-passed through the needle-punch loom at 90 ° rotation after each pass.
The preform is then flipped back into place prior to flipping and passed further through needle punching without the addition of any further fiber material. As mentioned above, the preform is rotated between successive needle punch loom passes. The preform is then removed from the shipping board. When the preform distorts or stretches from its desired annular configuration, a concentric preform, such as preform 80 shown in FIG. 9, is cut from it in the usual manner, eg, by hydraulic die technology. . When using curved blades, due to the inherent non-uniformity when curving otherwise uniform straight, flattened tubular blades, as well as the overlap of the ears of a pair of laterally adjacent blade tapes. for,
The upper surface 81 of the preform 80 may be somewhat arcuate. The lower surface 82 of the preform 80 is flat because it was in supporting contact with the surface 92 of the shipping board. The jig 90 described in Example 2 can be reused. If the transport board 93 becomes compressed through use, an additional layer of PAN or OPF or other suitable material can be added. If the central mold 91 becomes sponge-like after repeated passes through the needle-punch loom, for example if it is made of fibrous material, it should be replaced with a new central mold.

Resulting Needle Punched Structure 80
Was then subjected to CVD densification in the usual manner to an appearance similar to disk 10 shown in FIG.
It is possible to manufacture a friction disc that does not fluctuate around D. As used herein, "density" is determined by weighing a specimen of known size, such as that obtained by machining from the area of interest of a larger specimen, and weight / unit value, eg, g
It is represented by / cc. As used herein, "bulk density" is the weight / unit volume of the entire test piece, and is usually g /
Represented as cc.

A plurality of such densified discs made in accordance with the present invention were machined and assembled in the usual manner, US Pat. No. 4,018,482, US Pat. No. 4,878,563. And U.S. Pat. No. 4,61
Multiple disc brakes, similar to those shown and described in US Pat. No. 3,017, can be formed. For a final machined friction disc of 1.2 inches thick, a preform with an appearance similar to that shown in FIG. 9 with a thickness of about 1.8 inches is suggested. Shrinkage of about 10-15% by volume is expected during the conversion of OPF to carbon fiber by known methods.

Fibers such as cotton or rayon or fugitive fibers such as polyester fibers may be introduced during manufacture to enhance processability. As used herein, the term "unstable" means a material that is removed or destroyed during subsequent processing, by extraction or melting or pyrolysis, for example, during subsequent furnace treatment of the friction discs that it makes. . Cotton and rayon fibers are not considered unstable as they leave carbon fibers during oven treatment. Cotton and rayon fibers are "carbon fiber precursors"
It is thought to be inside. It is believed that in certain preferred embodiments, such cellulosic or labile fibers can be blended with staple OPF to form the unidirectional member to form the blended yarn for use. The use of such blended staple fiber yarns is expected to facilitate the production of unidirectional members of varying size and / or other properties depending on the nature of the constituent staple fibers. Recirculated or virgin OPF staples can be used in the manufacture of yarns formed into braided fabrics or other fiber tapes to be used in the manufacture of shaped fiber structures of the present invention. The braid, woven or knitted structure according to the invention can be completely formed from recycled OPF.

When subjected to all of the fiber material methods described herein, the tow is preferably the PAN fiber in the oxidized form. Producing suitable preformed discs from PAN fiber of raw fiber material, then oxidized PAN
Contrary to the continuous oxidation method used for the production of fibers, such preforms can be oxidized in a batch process, which means that especially prior to oxidation, PAN fibers do not have the desired high density, It also does not seem economical because it cannot withstand the high temperatures of the furnace cycles that are to be used subsequent to the formation of the preformed disc.

The present invention is illustrated using a tape of flattened tubular braids, each of which provides two fabric layers, except for the lengthwise-extending lip, but also the tubular braid Slitting in the direction to form a tape with a single fabric layer rather than two fabric layers, or the use of other forms of fiber tape, including woven, knitted and needle punched tapes of the present invention. Enter the range.

It is also believed that it is possible, but not preferred, to use carbonized tow. The carbonized tow can have a higher density compared to OPF, including but not limited to 1.74-1.78 g / cc. Disc preforms made from such carbonized tows can have a higher density as they enter subsequent furnace cycles, thus requiring shorter initial times in such subsequent furnace cycles. Can be expected to be about 1.79 g / cc
It may be difficult to densify to the desired final density in the region of about 1.85 g / cc. Due to the electrical conductivity of such carbonized tows, the electrical components of such machines must be sealed in a manner that prevents conductive particulate matter from the tow from shorting such electrical devices. I won't. Machines of this type, including braiding machines and needle punch looms, are commercially available.

Although the present invention has been described with respect to the use of tows,
It is within the scope of this invention to use yarns formed from continuous filaments or staple fibers or blends thereof in place of tows.

[Brief description of drawings]

FIG. 1 is an isometric view of a friction disc according to an aspect of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along line 2-2 of FIG. 1 and schematically depicts the distribution of fibers therein.

FIG. 3 is a schematic isometric projection of a rotary needle loom.

FIG. 4 is an enlarged schematic depiction of a representative needle used in the needle loom of FIG.

FIG. 5 is a schematic side view of a tubular braid structure having a braid angle α.

FIG. 6 is a plan view of a flattened linear tubular blade structure having a blade angle α of 40 °.

FIG. 7A is a cross-sectional view of FIG. 6 and B is also a cross-sectional view of another embodiment of a flattening tubular blade containing longitudinal axes that are unequal spaced from one another. is there.

FIG. 8 is an exploded cross-sectional view of an embodiment of an annular preform according to the present invention formed from a spiral inserted between a first and a second.

FIG. 9 is an enlarged cross-sectional view of an embodiment of a needle punched structure in accordance with an embodiment of the present invention.

FIG. 10 is an isometric view of a jig used in the practice of the present invention.

FIG. 11 is a schematic plan view of an embodiment of a preform according to the present invention formed from a pair of parallel pre-cured overlapping blades.

12A-12E are lines 11A-11 of FIG.
It is a schematic sectional drawing represented along A, Comprising: It is sectional drawing which describes the change of a blade tape.

FIG. 13 is a schematic plan view of an embodiment of a preform according to the present invention formed from a plurality of parallel overlapping blades.

FIG. 14 is a schematic cross-sectional view taken along line 13-13 of FIG.

FIG. 15 shows a single, overlapped,
FIG. 6 is a schematic plan view of an embodiment of the invention formed from a spirally wound blade.

FIG. 16 is a plan view schematically depicting an embodiment of an apparatus for the manufacture of curved blades for use in the present invention.

FIG. 17 is an embodiment of a pullout device and FIG.
FIG. 7 is an enlarged plan view schematically illustrating the aspect of the blade winding device shown in FIG. 6.

FIG. 18 schematically depicts means for driving juxtaposed frustoconical take-up rolls, means for adjusting the gap between frustoconical rolls, and means for adjusting their nip pressure. FIG. 18 is an end view of the curved blade manufacturing apparatus embodiment taken along line 17-17 of FIG. 17.

19 is a schematic end view taken along the line 18-18 of FIG.

FIG. 20 is a schematic end view of a braider depicting certain preferred arrangements of members to be bladed.

FIG. 21 is a schematic cross-sectional view of another embodiment of a preform according to the present invention formed from a tape of side-by-side contacting fibers.

FIG. 22 is a schematic cross-sectional view of another embodiment similar to FIG. 21.

FIG. 23 is a schematic cross-sectional view of another embodiment of a preform according to the present invention formed from a tape of side-by-side contacting fibers.

FIG. 24 is a schematic cross-sectional view taken along the line 23-23 of FIG. 23.

FIG. 25 is a schematic cross-sectional view of another embodiment similar to FIG. 21.

[Explanation of symbols]

10 Friction Disc 12 Toe 14 Inner Cylindrical Peripheral Surface 16 Outer Cylindrical Peripheral Surface 17 Flat Parallel Wear Surface 18 Flat Parallel Wear Surface 20 Area 22 Area 24 Center Area 50 Blade 54 'Unidirectional Member 60 Flattening Blade 60 'Flattened tubular blade 62 Folded region 63 Folded region 66 Longitudinal lip 66' Inner lip 67 'Outer lip 67 Longitudinal lip 71 Spiral rotation 72 Addition Blades 76 flattened partially overlapping blades 80 preform 81 upper surface 82 lower surface 90 support jig 91 center mold 92 large flat surface 93 flat transport board 99 axis 100 preform disc 101 spiral rotation Body 102 blade, flattening pre-curing blade 103 blade, flattening preliminary Curing blade 103 'blade 120 preform disc 123 flattened partially overlapping blade 124 flattened partially overlapping blade 125 flattened partially overlapping blade 126 flattened Partially overlapping blades 127 Flattened partially overlapping blades 128 Flattened partially overlapping blades 154 Unidirectional members 156 Ear portions 157 Ear portions 162 Folded back regions 163 Folded back Area 163 'Overlap range 164' Central area 172 Inner periphery, folded area 172 'Overlap area 173 Outer periphery, folded area 180 Braiding machine 186 Axial midline 189 Motor 190 Cree 200 curved blade forming device 201 blade 202 fiber material 203 one-way member, fiber material 210 forming ring 220 drawing device 222 frustoconical roll 223 shaft 224 nip 226 single worm gear 227 complementary teeth 229 motor 230 reciprocating means 240 multiple cores Curved chute 250 Rotatable winding device 251 Motorized screw 252 Motor 253 Flange member 254 Vertically protruding pin 255 Lower flange 256 Winding package, bobbin 257 Center groove 258 Center hub 259 Stationary nut 260 Subframe 281 Layer 282 Layer 283 Fiber Tape Part 284 Stitch 291 Layer 292 Layer 300 Preform Disc 301 Fiber Tape 302 Layer 303 Layer 310 Preform

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location D04H 1/42 D04H 1/42 EA 1/46 1/46 Z (72) Inventor Philip W. Sheehan United States, Colorado 81007, Pueblo West, South Pinhide Live 415

Claims (36)

[Claims] 1. A method of making a multi-layer near net shape fiber structure having width and thickness; one layer of fibrous material on top of another layer of fibrous material to form a flat laminate. At least one of said at least two laterally adjacent portions of a fiber tape narrower than the fiber structure to be manufactured, each layer of which has a width approximately corresponding to the fiber structure to be manufactured; Producing layers; and then needlepunching the laminate to crosslink these layers with fibers dislocated from these layers and extending in a direction substantially perpendicular to the planes of these layers. A method comprising. 2. The one layer is further provided by partially overlapping the peripheral ears of at least two laterally adjacent portions of a fiber tape having a width narrower than that of the fiber structure to be manufactured. The method of claim 1 including producing a layer. 3. The method further comprises manufacturing the one layer by abutting at least two laterally adjacent ears of a fiber tape that is narrower than the fiber structure to be manufactured. The method according to item 1. 4. The method of claim 1, further comprising manufacturing the one layer by stitching at least two laterally adjacent portions of a fiber tape that is narrower than the fiber structure being manufactured. Method. 5. The method of claim 1, further comprising laminating a plurality of said one fiber layer each formed of a partially braided fiber tape portion. 6. The method of claim 1 further comprising the step of producing the one layer of partially overlapped fiber tape portions and then laminating the one layer with another fiber layer of a different structure. the method of. 7. The method of claim 1 further comprising manufacturing the tape as a flattened tube braid and then introducing unidirectionality into the braid when the braid is manufactured.
The described method. 8. The fiber tape forming the one layer is further manufactured in a flattened tube braid having an upper layer and a lower layer, and then the unidirectional of the upper layer of the braid is made into the unidirectional of the lower layer of the braid. The method of claim 7 including manufacturing laterally offset with respect to each other. 9. The method further comprises manufacturing the one layer as a flat annular body, the annular body adjoining a fiber tape between an inner diameter peripheral edge and an outer diameter peripheral edge of the annular body. A spiral wound and then manufactured by overlapping the peripheral ears of adjacent bends of the tape.
The described method. 10. The method further comprises producing the one layer as a flat annular body, the annular body adjoining a fiber tape between the inner peripheral edge and the outer peripheral edge of the annular body adjacent thereto. A spiral wound and then manufactured by abutting the peripheral ears of adjacent curved portions of the tape.
The described method. 11. The method further comprises offsetting an ear portion of a continuous curved portion of the fiber tape forming the one layer with respect to an ear portion of a curved portion of the tape forming the next one layer. Item 10. The method according to Item 10. 12. The method of claim 9 further comprising forming the fiber tape as a tube braid and then introducing unidirectionality into the braid when the braid is manufactured. 13. The method of claim 1, further comprising producing a flat annulus, wherein the annulus is produced by helically winding at least two fiber tapes partially overlapped laterally. the method of. 14. The method of claim 7, further comprising varying the unidirectional magnitude in a predetermined manner. 15. The method of claim 7, further comprising varying the unidirectional spacing in a predetermined manner. 16. The method further comprising producing an annulus and maintaining the volume of the fibers substantially uniform from the portion adjacent the inner diameter periphery of the annulus to the portion adjacent the outer diameter periphery of the annulus. The method described in 1. 17. The method of claim 1, further comprising manufacturing the annulus and increasing the volume of fibers in at least one of the inner and outer perimeter edges of the annulus and its adjacent portion in a predetermined manner. The method described. 18. The structure of claim 6, wherein the structure produced is a flat arch and the width of the structure corresponds to the radial distance between the inner and outer edges of the arch. Method. 19. The method of claim 9 wherein the tape is a braided tape spirally disposed between the inner and outer diameter perimeters of the annulus and from the bottom to the top of the annulus. 20. The method of claim 19 wherein the layers are laterally offset so that the ears of the tape are not aligned over the height of the stack. 21. A plurality of fiber tapes are spirally wound in the same direction and overlapped with each other to produce a ring-shaped body composed of fiber layers arranged alternately, and at least one of the fiber tape layers arranged alternately is a ring-shaped body. The method of claim 1, wherein the method is formed of a plurality of braided tapes having a width narrower than a radial distance between the inner diameter peripheral edge and the outer diameter peripheral edge. 22. A fiber tape manufactured from the group consisting of PAN fibers containing OPF, carbon fibers, graphite fibers, ceramic fibers, carbon fiber precursors, ceramic fiber precursors, and mixtures thereof. The method of claim 1, wherein the method comprises: 23. The method of claim 1, further comprising bonding the crosslinked layers with a matrix selected from the group consisting of carbon, ceramics, carbon precursors, ceramic precursors, and mixtures thereof. Method. 24. A shaped fibrous structure having a width and a thickness comprising a flat laminate having one layer of fibrous material disposed over one layer of another fibrous material, each layer Has a width approximately corresponding to the width of the fibrous structure; one of said layers is formed by at least two fiber tape sections which are adjacent in a parallel lateral direction whose width is narrower than the width of the fibrous structure; A shaped fibrous structure that is bonded by going and dislocating from the layer and cross-linking the layer by fibers that are oriented in a direction generally perpendicular to the plane of the layer. 25. The structure according to claim 24, wherein the ears of the tape portions that are adjacent to each other in the lateral direction are sewn together. 26. The structure of claim 24, wherein the ears of the laterally adjacent tape portions are superposed. 27. The structure of claim 24, wherein the one of the fibrous layers is a braided layer. 28. The tape layer is manufactured in the group consisting of PAN fibers containing OPF, carbon fibers, graphite fibers, ceramic fibers, carbon fiber precursors, ceramic fiber precursors and mixtures thereof. Manufactured with yarn
25. The structure of claim 24, further comprising a fiber binding matrix selected from the group consisting of carbon, ceramics, carbon precursors, ceramic precursors, and mixtures thereof. 29. A flat arcuate shape, the width of which corresponds to the radial distance between the inner and outer peripheral edges of the arched shape, and the tape portion of which is arcuately formed. Item 24. The structure according to Item 24. 30. A generally flat annular shape, the width of which is defined as the radial distance between the inner and outer peripheral edges of the annular shape, with laterally adjacent fiber tape portions extending annularly. 25. The structure according to claim 24. 31. Further comprising: a plurality of spirally wound tapes arranged to form a flat annulus having a plurality of layers, each layer being a plurality of parallel tapes partially overlapped. The structure according to claim 24, which is formed. 32. A plurality of tape portions having a plurality of spirally wound tapes arranged to form a flat annulus having a plurality of layers, each layer abutted and sewn together. The structure according to claim 24, which is formed of 33. The successive layers are laterally offset from each other,
33. The structure of claim 32, wherein the ears of the spirally wound tape forming each layer are not evenly aligned across the height of the stack. 34. A structure having a flat arcuate shape, the width of which is defined as a radial distance between an inner peripheral edge and an outer peripheral edge of the arcuate shape, the inner peripheral edge and the outer peripheral edge of the structure. 25. The structure according to claim 24, wherein the fiber volume is substantially uniform except for the portion adjacent to the peripheral edge. 35. The structure according to claim 34, wherein the fiber volume of at least one of the inner peripheral edge and the outer peripheral edge of the structure and the portion adjacent thereto is increased. 36. At least one of the fiber tape portions comprises:
25. The structure of claim 24 which is a flattened tube braid having unidirectional.