|Publication number||US3661491 A|
|Publication date||May 9, 1972|
|Filing date||Sep 17, 1970|
|Priority date||Sep 30, 1968|
|Publication number||US 3661491 A, US 3661491A, US-A-3661491, US3661491 A, US3661491A|
|Inventors||Richard Lloyd Troyer|
|Original Assignee||Johns Manville|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (10), Referenced by (32), Classifications (15)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States Patent Troyer [451 May9, 1972  MEANS FOR PRODUCING FIBROUS PRODUCTS HAVING INTEGRAL TONGUE AND GROOVE EDGES  Inventor:
 Assignees Johns-Manville Corporation, New York,
221 Filed: Sept. 17,1970
21 Appl.No.: 72,989
Richard Lloyd Troyer, Maumee, Ohio Related U.S. Application Data  Division of Ser. No. 763,655, Sept. 30, 1968, Pat. No.
3,057,022 10/1962 Bar et a1. ..18/4 B X 3,066,352 12/1962 Ryberg ..18/4 B X 3,197,530 7/1965 Miller et al..,.. 264/67 X 3,242,527 3/1966 Rosenberg ..18/4 P 3,261,897 7/1966 Munk 18/16 R X 3,353,236 11/1967 Stedman 18/2 .1 X 3,395,204 7/1968 Olsson et a1 ..264/67 UX 3,431,595 3/1969 Plum et al. ..18/16 R X 3,583,030 6/1971 Terry et a1. ..18/4 P Primary Examiner-J. Howard Flint, r. Attorney-John A. McKinney and Robert M. Krone 57 ABSTRACT Means for consolidating, shaping and fixing the consolidated density and shape of a body of loose mass of fibers containing binders throughout to produce products of fixed configuration and density, which includes the concerted forming of integral tongue and/or groove longitudinal edges for effective complementary uniting of components with a like adjacent component, and the resulting tongue and/or groove fibrous product.
6 Claims, 4 Drawing Figures PATENTEDMAY 9 1912 3,661,491
INVENTOR. RlCHARD LLOYD TROYEK (\rrozuev MEANS FOR PRODUCING FIBROUS PRODUCTS HAVING INTEGRAL TONGUE AND GROOVE EDGES This application is a division-of my copending application Ser. No. 763,655 filed Sept. 30, 1968, now U.S. Pat. No. 3,549,738.
BACKGROUND OF THE INVENTION This invention relates to the manufacture of bonded fibrous products, and in particular to the fonning and curing of loose masses of fibrous material, containing throughout thermally activable binder material, into coherent, permanently shaped, semi-rigid but resilient and flexible, or rigid fibrous products, typically of low density structures but of substantially increased densities and integrity over the initial loose mass of fibrous material. While this invention is primarily concerned with the manufacture of products from glass fibers, the means thereof are also applicable to the formation of products from fibrous materials of other compositions or sources of asubstantially stiff and resilient nature including common inorganic fibers such as rock, mineral, or slagwools and related siliceous fibers, and even organic fibers exhibiting sufficiently stiff resilient characteristics such as relatively coarse wood fibers. Although the low density products formed by the apparatus of this invention are primarily designed for use in thermal insulation applications, the products from this apparatus are also amenable to the manufacture of panels, tiles, sections, etc., for other or combined utilities such as decorative wall or ceiling construction units alone or of composite functions providing effective thermal and/or sound insulations.
One of the most common means of uniting and joining abutting sections of many construction materials particularly lumber and bonded low density fibrous units or sections such as wall or ceiling panels or tiles, consists of conventional tongue and groove edges for complementary mating of adjoining components. Typical means of forming conventional tongue and groove edges comprise cutting away or.routing out of material with saws, knives, or other blade devices to effect this conventional joint substantially similar to the forming of tongue and grooved lumber. However, because of the relatively low strength inherent in such low density and open material in typical bonded fibrous insulations which may range down to about 1 pound density per cubic foot, the removal of substantial amounts of the material massalong the more vulnerable edges to form either a conventional tongue or groove structure further extensively weakens the already fragile edge portions. Moreover, because of the soft consistency and low strength of the initial material-loose fibers containing unactivated binder-it is usually necessary to complete the formation of the product including the substantial total cure of the binder to achieve maximum integrity prior to subjecting the product to such aggressive action as cutting away edge portions with saws or routers, thereby necessitating a second or subsequent independent operation in the manufacture following product formation and curing.
On the other hand, the prior art practice of unit molding of such low density bonded fibrous products such as wall or insulating panels, ceiling tile, etc., wherein the same operation includes forming the edge portions with integral tongueand/or grooves of typical configuration has been confined to batch or single unit forming procedures of relatively slow and cumbersome production rates which are costly. Also, the imparting of typical tongue or groove configurations, particularly the latter type of joint, entails awkward and involved uses of mold forms and intricate molds and procedures, all of which significantly increase costs without enhancing the product characteristics or value. Other single unit molding operations entail the formation of a laminate composed of two, three, or more sections, superimposed in staggered arrangement to provide tongue and grooved edges. Such constructions are particularly susceptible to delamination or separation and, moreover, require the use of intermediate adhesives, increasing the density and decreasing thermal and acoustical efficiency while reducing resiliency and flexibility, as well as adding to costs.
SUMMARY OF THE INVENTION This invention comprises a combination of means which enables the effective manufacture on an economical continuous basis of relatively low density, semi-rigid but flexible, or rigid shapes of permanently bonded fibrous products having integrally formed therein typical tongue and/or grooved edges of increased density and in turn strength and durability. Specifically the invention constitutes an apparatus for the continuous forming of low density fibrous products such as insulation sections or wall and ceiling finishing panels by consolidating and shaping a body of a loose mass of fibers containing binder and fixing the consolidation or density and shape imparted thereto by curing the-binder while substantially simultaneously therewith or during the foregoing continuous operation additionally forming typical tongue and/or groove structures continuing alongone or both longitudinal edges of the product.
It isthe principal objective of this invention to provide an improved and economical means for the consolidation and shaping of a body of loose mass of fibers containing binder throughout and permanently fixing the consolidation and shape including integral tongue and/or groove structures of typical configuration and increased strength and resistance to breakage over the balance of the product body extending along the longitudinal edges thereof.
BRIEF DESCRIPTION OF THE DRAWINGS This invention will be more fully understood and further objects and advantages thereof will become apparent when reference is made to the following detailed description of the preferred embodiment of the invention, and the accompanying drawings, in which:
FIG. 1 is a schematic side view illustrating the means of this invention for producing fibrous products having integral tongue and/or groove edges;
FIG. 2 is a schematic top view of the means of FIG. I, further illustrating the arrangement of means of the invention;
FIG. 3 is an endview of the heated press taken on a plane along line 3-3 of FIGS.' 1 and 2, looking into the entrance of the heated press and showing the tongue and groove forming mold units; and
FIG. 4 is a perspective view of a typical low density product formed by the apparatus of this invention illustrating the in tegrally molded tongue and groove longitudinal edges.
DESCRIPTION OF THE PREFERRED EMBODIMENT In this invention a semi-rigid but resilient and flexible, or rigid, relatively low density, bonded fibrous product suitable for thermal or sound insulation utility, or for panel or tile finishing application, is formed by continuously passing a moving body of loose mass of fiber containing binder throughout, through compressing and heating means comprising a cooperating pair of spaced-apart opposing, smooth surface, heated platens which compress and form the two major surfaces of the body of loose mass of fiber to the approximate shape or thickness and density of the designed final product while heating the compressed and/or shaped mass sufficiently to set the binder content therein and permanently fix the imparted consolidation or density, thickness and shape. The invention additionally constitutes in combination with the foregoing apparatus for the continuous operation of forming by consolidation and shaping and thus securing the binder to fix the consolidated density and shape, and substantially simultaneous therewith, the apparatus for forming of integral tongue or groove longitudinal edges extending the length of the continuously formed product.
Referring to the drawings, there is schematically illustrated in FIG. 1, a manufacturing operation and means therefore for the production of semi-rigid, relatively low density insulating board, or the like products, from glass or other equivalent stiffly resilient fibers and thermally activable binder, having a generally rectangular transverse cross-sectional configuration from a body of loose, random intermingled mass of fibrous material containing the binder throughout. As shown in FIG. 1, body of a loose mass or bed of binder containing fibrous material, such as common glass fibers produced as disclosed in U.S. Pat. No. 3,129,084 to Labino, is carried by conveyor 11, or any appropriate transporting means, and continuously fed to the compressing, shaping and thermal setting means 12. An integral groove is formed in one side of the product between its major surfaces by cutting a marginal slit 13 in one longitudinal edge of the moving body 10 of loose mass of fibers with a revolvingcircular knife 14, or other equivalent means such as a revolving saw or reciprocating knifeor saw, extending along thelength thereof and generally intermediate and parallel to the two major surfaces of the moving body 10. The depth of the cut forming the marginal slit is such as to exceed .the designed depth of the final groove. Upon cutting this marginal slit, it is preferred that the cut surface of the slit be heated to a temperature sufiicient to substantially activate the binder in the immediate area and set the same to prevent fibrous material from tearing loose and breaking away during subsequent forming and curing operations, and thereby fouling or clogging the mold, disrupting the operation and/or the consistency of the product leaving voids or areas of under density. This expedient preliminary precuring'of the cut surfaces of the marginal slit can be achieved by means of an appropriate heated plate 15, inserted into position within the slit 13, cut into the moving body 10 by revolving knife 14 whereby the cut surface of the slit comes into passing contact with the heated plate as the body moves to the compressing, shaping and thermal setting means 12. 1
Following cutting the marginal slit l3, and the preferred but optional curing of the cut internal surfaces of the slit, the body of loose mass of binder containing fibers enters the compacting, shaping, thermal setting means 12, comprising a pair of heated opposed platens 16 and 17, each having tapered por- 1 tions 18 and 19, respectively, providing an entrance hereto and facilitating compression of the loose mass of unbonded fibers. The heated opposing platens l6 and 17 each comprise a broad surface of substantially flat plane 20 and 21, respectively. of sufficient area or length in relation to forming speed and product thickness to enable adequate heating through the low density body 10 of loose fibers containing binder to substantially complete the cure of the thermally activable binder at least to the point of permanently fixing the imposed shape and density, and of such width as to accommodate the fiber mass andform the product dimensions. Each platen l6 and 17 is provided with suitable heating means, not shown, such as electrical resistance heaters, induction coils, or internal steam conduits or other appropriate sources to produce adequate heat to effect the thermal activation and curing of the binder.
As the body of loose mass of fiber containing binder approaches and enters the compacting shaping and thermal setting means 12, the two major surfaces of the fibrous body 10 are compressed upon entering the gradually treated sections 18 and 19 of the spaced-apart, generally parallel opposing heating platens l6 and 17, respectively, to approximately the ultimate thickness and shape and density of the desired product, which, of course, is governed by the distance spaced between the substantially parallel platens 16 and 17. While thus compressed and conformed to shape, the moving body is permanently fixed to the imparted shape and density by the substantially simultaneous application of heat which thermally activates and sets the heat curable binder.
In concert with the continuous compression, shaping and heat curing of the overall moving body 10 of loose binder containing fiber, a mold form 22, in combination with the means 12, is positioned generally intermediate the platens 16 and 17, and so as to penetrate the slit 13 cut in the margin of the body 10 to an extent at least to the depth of the desired edge groove in the ultimate product, and of a thickness to expand the slit 13 to the width of the groove of the desired utlimate product. The mold 22 is interposed within the marginal portion of the moving body 10 of fibers for a length preferably substantially corresponding to the length of the generally parallel section of platens 16 and 17, and at least for a duration sufficient for the curing of the binder of the fibers to permanently fix the edge groove. As an alternative to optional heated plate 15, mold form 22 may be independently heated to facilitate activation of the cure. However, the heating of the mold form 22 is not usually necessary since the heat transmitted from platens 16 and 17 normally more readily penetrates the reduced portions of the body forming the walls of the groove.
The opposite longitudinal edge of the body 10 of loose binder containing fiber is correspondingly provided with a complementary edged tongue with a forming mold which may be provided by continuing the sloped tapered sections 18 and 19 of platens 16 and 17, respectively, in a limited marginal area of these platens extending inwardly at least equivalent to the length of the tongue of the designed product and such as to effectively mate with the corresponding groove. The marginal continuations of platens 16 and 17 continue to approach each other to the point of providing secondary or minor spacedapart platen mold surfaces 23 and 24, spaced a distance from each other, generally intermediate surfaces 20 and 2], approximately equivalent to the width of the tongue of the designed products and such as to effectively mate with the corresponding grooves. Optionally, to simplify the compressing and heating platen structure, the tongue-forming mold surfaces can be constructed of separate or a unitary cooperating pair of opposing mold faces, which are mechanically combined with primary consolidating, shaping, and heating platens 16 and 17.
Accordingly, as the body 10 of loose mass of binder containing fiber moves from conveyor 11, or other suitable transporting means, and following the cutting of a marginal slit 13, in passing contact through compressing, shaping and thermal setting platens 16 and 17, groove mold form 22 and tongue mold surfaces 23 and 24, in concerted cooperation with platens 16 and'l7, each respectively form a continuous groove 25 and continuous tongue 26 integral with the product such as shown in board 27 of FIG. 4, extending along the longitudinal edge portions thereof, by further consolidating or densifying the material shown in areas 28 and 29 which increasesthe strength of these formerly vulnerable areas of reduced mass and thereby minimizing breakage.
Optionally products of this invention may be produced with both longitudinal edges each having a grooved marginal area as shown 25 or with both edges each provided with a tongue as shown in 26 to cooperate with independent appropriately corresponding mounting frames or means.
This invention is particularly directed to the apparatus for the manufacture of insulating products from resin binder containing fibrous materials comprising a loose random mass of glass fibers having densities of up to about 10 pounds per cubic foot but typically less than about 1 or 2 pounds per cubic foot, and containing dispersed throughout between about 3 and 25 percent of resinous binder material such as a thermosetting resin of the phenol formaldehyde type, although the means of the invention are also applicable with the use of thermoplastic or other thermally activable binders. However, with a thermoplastic binder, the product shape, density, etc., must be maintained through to cooling to fix the same which can be provided for by extending the molds beyond the heated area and/or with cooling means. These very loose and low density masses of resin containing glass fiber materials can be formed by means of this invention into.
fibrous products for thermal insulating applications having relatively low densities of between about 0.5 to about 20.0 pounds per cubic foot and preferably of about 1 to 2 pounds up to about 8 pounds per cubic foot, of substantially any given transverse cross-section or configuration. And in the lower density ranges, although the shape and density are permanently fixed, these products are nevertheless sufficiently flexible to be bent or folded to conform to conditions, and will return upon release to original shape and density without damage.
As is frequently expedient in thermal insulations of low densities and thus often highly vapor permeable constructions, a vapor barrier 30 comprising metal foil or plastic sheet, etc., can be applied to or superimposed over the surface of the fibrous product of this invention and by extending the same from within the groove 25 across one surface and continuing out along the tongue 26. Thus the insulation section, when joined with like abutting units, forms a continuous vapor barrier with the cooperating tongue and groove joints conveniently forming a seal between the sections. And to facilitate the sealing effect, it is preferred that the tongue 26 and cooperating groove 25 should be correspondingly tapered to enable a force fit which is easily achieved with the resilient compressible materials of this invention.
What I claim is:
1. Apparatus for producing shaped and bonded low density fibrous products having integral tongue and groove longitudinal edges, comprising the combination of:
a. means for cutting a marginal slit in one longitudinal edge of a moving body of loose mass of fiber containing binder throughout along the length of said body intermediate and parallel to the two major surfaces of the body,
. means for compressing the thus cut moving body of loose mass of fiber containing binder on its two major surfaces to shape the same and to heat the compressed body to cure the binder and fix the imparted shape and com pressed density in the compressed body of loose mass of fiber and binder,
. means comprising a mold of the edge groove to be formed combined with said compressing and heating means and positioned to penetrate the marginal slit cut into the longitudinal edge of the moving body of loose mass of fiber containing binder while said body is compressed to shape and heated to cure the binder thereof to fix the imparted shape and compressed density whereby simultaneously with the said compressing and heating to shape and cure the binder of the body of loose mass of fiber to fix the imparted shaped and compressed density therein by the said means provided therefor, the mold of the edge groove cooperates with said compressing and heating means to form an integral groove of the marginal slit within the longitudinal edge, and
d. means comprising a mold of the edge tongue to be formed combined with said compressing and heating means and positioned to receive a marginal portion of the longitudinal edge of the moving body of mass of fibers containing binder opposite the edge out while said body is being compressed to shape and heated to cure the binder thereof to fix the imparted shape and compressed density,
and which further compresses the said marginal portion of the longitudinal edge within the said mold of the tongue during the compression to shape and curing of the binder to fix the shape whereby simultaneously therewith the mold of the edge tongue cooperates to form an integral tongue in the other longitudinal edges.
2. The apparatus of claim 1 wherein the mold of the edge tongue comprises a pair of opposing, spaced-apart plane mold faces.
3. The apparatus of claim 1 wherein the means for cutting the marginal slit comprises a revolving disk knife.
4. The apparatus of claim 1 wherein said mold includes a heated plate positioned intermediate and in line with the cutting means and the mold of the edge groove to penetrate the slit cut in the marginal portion prior to the penetration of the mold of the edge groove into said slit to initiate the cure of the binder contained throughout the fiber in the area of the surfaces of the slit.
5. Apparatus for producing shaped and bonded low density fibrous products having integral tongue and groove longitudinal edges, comprising the combination of:
a. means for cutting a marginal slit in one longitudinal edge of a moving body of 'loose mass of fiber containing binders throughout along the length of said body intermediate and parallelto the two major surfaces, means for compressing the thus cut moving body of loose mass of fiber containing binder on its two major surfaces to shape the same and to heat the compressed density in the compressed body of loose mass of fiber and binder, and
c. means of comprising a mold the edge groove to be formed combined with said compressing and heating means and positioned to penetrate the marginal slit cut into the longitudinal edge of the moving body of a loose mass of fibers containing binder while said body is compressed to shape and heated to cure the binder thereof and fix the imparted shape and compressed density whereby simultaneously with the said compressing and heating to shape and cure the binder of the body of loose mass of fiber, to fix the imparted shape and compressed density therein by the means provided therefor, the mold cooperates with said compressing and heating means to form an integral groove of the marginal slit within the longitudinal edge.
6. The apparatus of claim 5 wherein said mold includes a heated plate positioned intermediate and to penetrate the slit out in the marginal portion prior to the penetration of the mold of the edge groove into said slit to initiate the cure of the binder contained throughout the fiber in the area of the surfaces of the slit.
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|U.S. Classification||425/297, 425/517, 425/306, 425/501, 425/509, 425/510|
|International Classification||B29C67/24, B27N3/18|
|Cooperative Classification||B29K2309/08, B27N3/183, B29C70/10, B29C67/249|
|European Classification||B29C70/10, B29C67/24F3, B27N3/18A|