US2521984A - Fibrous unit - Google Patents
Fibrous unit Download PDFInfo
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- US2521984A US2521984A US748983A US74898347A US2521984A US 2521984 A US2521984 A US 2521984A US 748983 A US748983 A US 748983A US 74898347 A US74898347 A US 74898347A US 2521984 A US2521984 A US 2521984A
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- fibres
- batt
- unit
- fusible
- rim
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D39/00—Filtering material for liquid or gaseous fluids
- B01D39/14—Other self-supporting filtering material ; Other filtering material
- B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
- B01D39/1607—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
- Y10T156/10—Methods of surface bonding and/or assembly therefor
- Y10T156/1002—Methods of surface bonding and/or assembly therefor with permanent bending or reshaping or surface deformation of self sustaining lamina
- Y10T156/1039—Surface deformation only of sandwich or lamina [e.g., embossed panels]
- Y10T156/1041—Subsequent to lamination
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
- Y10T156/10—Methods of surface bonding and/or assembly therefor
- Y10T156/1052—Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing
- Y10T156/1054—Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing and simultaneously bonding [e.g., cut-seaming]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/14—Shredding metal or metal wool article making
- Y10T29/147—Metal wool bundling
Definitions
- This invention comprises a new-and improved fibrous unit having the advantages of many uses of high eiiciency as well asvbeing adapted for manufacture by automatic machinery atea rapid rateand at low cost.
- the present invention also includes within its scope the process herein shown of producing the fibrous unit of my invention. This is characterized by subjecting an annular zone of the batt to pressure between two surfaces compressing said zone of the batt and forming it into a relatively thin rim and to a bonding treatment to permanently maintain the rim, and then severing the portion of the batt disposed exteriorly of the rim.
- the unit is produced rapidly and at practically a single operation by merely presenting following description of several preferred embodiments thereof, selected for purposes of illustration and shown in the accompanying drawings in which:
- Fig.l is a" fragmentary view in cross-sectio ofainultieplyllter:unit
- f Y F1a-6 is a ske-view' view of thev unit Shown m i Figfi'l Ais a View, "similar to ',Fi'g. 1, showing a batt'with anunderlying ply of felt in operative! position' ⁇ beneath a'fring die," ,s
- FIG. 8' is asimilar view showing abatt with an' interpo'sedply 'of' fabric'or 'paper inoperative j'rigsjegic
- 1'1 and 1'2 are' fragmentary views in cross-section showing fibrous units of different ply l constructions'and l 4 s ⁇ Frag".
- -1,3 isa viensimiiar to Fig. 2, showing'ajj pl ⁇ te,n with a shallowv ring die adapted slightly; te'c'cmpress this bodyportion of the unit. ⁇ i
- Mitalieunit is designed for use asfau mier inar-a111111112 111ea1113t1e batt 'may beamed, bypicking andblending approximatelyb Ind almanner similanto thatpractisd in the manuy, factureof felt, but carrying thebatt only through I, the cardine stage and vleaving it in a soft, fluffy,
- the single ring die shown in Figs. 1 and 2 produces a filter flat on the face engaged by the platen II and somewhat convex or dome shaped at its other face.
- Fig. 4 I have illustrated a double ring die adapted to produce a filter dome shaped at both faces.
- This die - is like that shown in Figs. land y2 except that a ring I8 is mounted on the platen II opposite to the ring I4.
- the opposite face portions 20 and 22 of the batt are uncompressed and form the two domes of the filter within the compressed rim 2l, as shown in Fig. 6.
- a double dome filter of this nature can also be made by cementing together at their rims I6 two filters Il as illustrated in Fig. 5.
- Fig. 7 I have illustrated the making of the filter shown in Fig. 9 and comprising a fabric base 24 of felt or the like bonded tothe vfilter body 26 at the marginal rim 25.
- the batt IIJ and fabric 24 are placed on the platen II and the lter is formed by one stroke of the top platen i2 in the manner illustrated in Fig. -2.
- the fabric can also in like manner be applied to the ltop face of 'the iilter if desired and the filter body 29 will in that case be entirely enclosed within bottom and top fabric covers 28 and 30 as illustrated in Fig. l0.
- the fabric 24 is bonded ⁇ to the rim 25 of the body 26 by any suitable method such as incorporating a bonding fibre or element into the fabric or applying an adhesive orthe like thereto.
- the ⁇ filter can be produced with a less abrupt break between the fused edge and the dome shaped portion by employing a suitable separator of fabric or paper between the die and the batt in the forming operation, and in "8 I have illustrated such a separator 21 so disposed.
- the separator acts as a surface cushion between the die and batt and produces the product shown in'Fig. 11 and comprising a dome 32 merging more gently into the fused edge 33. It will 'be understood that the separator will be of a composition treated to cooperate with but not adhere to the product.
- the body portion of the lter thus farv described is loose, fluffy and wholly uncompressed and is adapted to function with high porosity and permeability. It may be desirable in some cases to yproduce a filter or the like of more compact composition and having decreased porosity and permeability, as the Vlter illustrated in Fig. 12.
- Fig. 13 I have illustrated the formation of 'such'a filter by 'employing a relatively shallow ring die 36. When the die descends the batt I within the annular ⁇ zone of the die is engaged by the top platen I2 and slightly compressed simultaneously with the compressing vof the lbatt at said zone. The resulting product is -a filter having a somewhat compressed dome with a fiat top surface 34 merginginto the fused edge 35.
- composition of the batt can be wool, rayon, ramie,
- a suitable thermoplastic fibre is added to effect fusing under heat to form the retaining rim I6.
- a batt constructed by blending 80% of India scribed in detail certain illustrative embodiments.k
- the filters shown in Figs. 9 and 10 having one or more cover layers of felt, flannel or the like at one or both faces, are employed under conditions where it is necessary to provide a filter having an open and porous batt-like face with a reenforcing secondary filter to strengthen the unit and screen out the ne particles which are not trapped by the primary lter.
- the weight and thickness of the batt before pressing can be varied to obtain a soft or hard fused edge, a thick or thin product, or one of different density, porosity, and permeability.
- the porosity, ⁇ permeability andv shape of the product can' also be varied by somewhat compressing ⁇ the inner filter portion as illustrated in Fig. 13.
- the filter as thus formed has increased dust Vretention efficiency and decreased porosity and permeability.
- the platen I2 be heated by an electrical heating unit I3 and such construction is satisfactory.
- one or yboth platens may .be steam heated and under those circumstances a convenient cycle has been found to be ⁇ a thirty second cycle including five seconds for pressing and cutting at 300 F. and ytwenty-five seconds for opening and closing.
- the design of the lower pressing plate is such that the fused 4edge portion is elevated-above the plate so that the unused portion of the batt is ⁇ not pressed and may be recarded thus reducing ywaste to a minimum. Further, instead of using an integral pressing and cutting die as shown in Figs. 1 and 2 vasteel ribbon die may be secured to the circumference of the ring-pressing portion of the die.
- I-t has been found desirable in some instances to include in the filter a fabricated reinforcing member, forexample, a sheet ofscreen wire.
- a fabricated reinforcing member forexample, a sheet ofscreen wire.
- two carded batts can be run into the press simultaneously with the Screen wire between-them and the three elements pressed and fused into a single filter unit.
- the invention is applicable to the production of other fibrous units as'gfor example, air conditioning filters, oil filters, auto filters, powder131is, cosmetic padding devices, etc. with or without the thermoplastic fibres.
- the subjecting of an annular zone of the batt to pressure between two surfaces determines the marginal border of the product'and effects the bonding of the fibres in the compressed zone to form permanently the retaining ring, and the severing of the outside .portion of the batt from the ring completes the product.
- the bonding will be Aeffected by suitable adhesives applied to te-zone to be compressed prior to the dieing operation, or by such other method as is found suitable and effective.
- a fibrous unit comprising a heterogeneous body containing intermingled fusible and non- .fusible fibres, the said fibres being compacted and unied by coalescence of the fusible libres in a thin fiat peripheral rim which is resilient and retains its shape permanently, and being present in the central area of the unit as a uiy relatively thick batt surrounded by the said rim.
- a fibrous unit comprising a heterogeneous body containing intermingled thermoplastic and non-thermoplastic fibres, the said fibres being compacted and the thermoplastic fibres unified by coalescence in a thin, fiat, relatively hard peripheral rim, and being present within the inner boundary of said rim in a thick, relatively soft batt, certain bres extending from the soft central batt into the harder peripheral rim.
- a fibrous unit comprising a body containing intermingled fusible and non-fusible fibres and embodying a central area which is relatively soft, thick and pervious to the passage of air and a peripheral zone which is relatively hard, thin and impervious to air and in which the fusible fibres are unified and coalesced in permanent compacted condition.
- a fibrous unit comprising a body containing intermingled fusible and non-fusible fibres, the mixed fibres forming a central area which is relatively soft, thick and pervious to the passage of air, and said central area merging into a unitary peripheral rim which is relatively hard, thin and impervious to the passage of air and in which the libres are compacted and held in shape by coalescence of the fusible fibres.
- a fibrous unit comprising two bodies in face to face contact and each containing intermingled fusible and non-fusible fibres forming a central area which is relatively thick and soft and a multi-ply peripheral rim integral with the bodies and relatively hard and in which the bres are held compacted by coalescence of the fusible fibres, the plies of the rim being adhesively united.
- a fibrous unit comprising a body containing intermingled fusible and non-fusible fibres, the said fibres forming a central area which is i 6 relatively thick and soft, and in which the fusible fibres are substantially free of coalescence, and being compacted and coalesced into a flat relatively stiff thin rim about said area which renders the unit self-contained and self-sustaining, and a fabric cover on at least one face of the unit.
- a fibrous unit comprising thermoplastic and j non-thermoplastic fibres mixed heterogeneously and compacted and fused into a relatively hard peripheral rim surrounding a relatively soft and substantially thicker center portion in which the fusible bres are substantially free of coalescence, and a sheet of fabric heat bonded to the said peripheral rim and covering at least one face of the unit.
- a filter unit comprising an intermediate, foraminous reinforcing sheet having upon each of its sides a relatively thick, fluffy batt of fusible and non-fusible fibres intermingled throughout the bodyr of the batt and surrounded by a marginal and relatively thin peripheral rim integral with the batts and comprising the marginal portion of the batts in which the fusible fibres are substantially free of coalescence compressed and bonded into a relatively thin retaining ring.
- a fibrous unit comprising a relatively thick and uiiy batt of fusible and non-fusible fibres intermingled heterogeneously throughout the body of the batt, a fabricated reinforcing sheet intimately associated with the fibres in the batt, and a marginal and relatively thin peripheral rim integral with the batt and supporting the margin of the reinforcing sheet, said rim comprising the marginal portion of the batt in which the fusible fibres are compressed and bonded by heat into a relatively thin retaining ring.
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- Chemical Kinetics & Catalysis (AREA)
- Nonwoven Fabrics (AREA)
Description
Sept., E2, i950 P. H. LANG 2,521,984
FIBROUS UNIT Filed May 19, 1947 /fu @M ZV- BY/wy Patented Slept. 12, V1956 l FiBRoUs UNIT; I
Philip H- Lallg, Summit, N. J assigner to Amen.
.ican Felt Company, Boston, Mass., `a=-corpora, .Y
tion of Massachusetts 1 Application May 19, 1947seris'1 N. 74s,9s3' *l 11 Claims.
-This invention comprises a new-and improved fibrous unit having the advantages of many uses of high eiiciency as well asvbeing adapted for manufacture by automatic machinery atea rapid rateand at low cost.
*I have discovered that al relatively thick battv ofV mixed fibres such as are commonly used in the production of felt, loosely associated but not com'- pletely fulled or hardenedpis highly effective as a lter of aerosols and other uses. I have, moreover, beensuccessful in solving the problem of Y incorporating such a loose batt into a self-sustaining unit in'which the construction of the loose batt ispreserved whilethe unit as a wholel may be conveniently stored, distributed and sembled in its operative position. -v
-One important field of use for the unit of my invention is as a lter for use in-vacuum'clean- 1 position beneath thelfifing die,y
unified by heat and pressure so that they form a thin peripheral rim which is resilient and retains its shape permanently, while the enclosed bres remain as a iluify, relatively thick batt surrounded by the said rim. In the construction described it will be seen that many of the individual fibres, both fusible and non-fusible, extend from the loose batt into the relatively hard compact rim, and thus the soft, thick, center portion of the unit is permanently united and anchored to the rim by which it is supported and sustained.
The present invention also includes within its scope the process herein shown of producing the fibrous unit of my invention. This is characterized by subjecting an annular zone of the batt to pressure between two surfaces compressing said zone of the batt and forming it into a relatively thin rim and to a bonding treatment to permanently maintain the rim, and then severing the portion of the batt disposed exteriorly of the rim. Thus the unit is produced rapidly and at practically a single operation by merely presenting following description of several preferred embodiments thereof, selected for purposes of illustration and shown in the accompanying drawings in which:
cotton withv rffthermoplastic cellulose' acetate A fibres, carding. the` blendedfibres into a batt V'I igsrl andZf'are views in elevation, partly in section-showinga battbeing operated upon'by" a-ringjshaped'fdie,` Eigf'is aplan view of a completed filter unit i' made 'by the process; i Figii is a view, similar to Fig. 2, showing coi-1' operativejring dies operating to form a vdouble- 2 faced iter'unit,""" Fig.l is a" fragmentary view in cross-sectio ofainultieplyllter:unit, f Y F1a-6 is a ske-view' view of thev unit Shown m i Figfi'l Ais a View, "similar to ',Fi'g. 1, showing a batt'with anunderlying ply of felt in operative! position'` beneath a'fring die," ,s
'Fig,"8'is asimilar view showing abatt with an' interpo'sedply 'of' fabric'or 'paper inoperative j'rigsjegic," 1'1 and 1'2 are' fragmentary views in cross-section showing fibrous units of different ply l constructions'and l 4 s `Frag". -1,3 isa viensimiiar to Fig. 2, showing'ajj pl`te,n with a shallowv ring die adapted slightly; te'c'cmpress this bodyportion of the unit. `i
The Compositicil'of'the batt offers awide rangei of choice Mitalieunit is designed for use asfau mier inar-a111111112 111ea1113t1e batt 'may beamed, bypicking andblending approximatelyb Ind almanner similanto thatpractisd in the manuy, factureof felt, but carrying thebatt only through I, the cardine stage and vleaving it in a soft, fluffy,
35,loosely compacted condition approximately 1/'2`ll 111011111 `ov'elralllsl1Cl11es$1 111 Fie'- 1 Such abatt; I0 sshown as supportedfupon the platen II of" a press. y Verticallyimovzable above the platen` I I isa plunger or` top platenA I2 provided with..\a hea-tingunitj andcarrying a ring die I4 having I a-shoulderedendiace .surrounded by a proiectx,=` circumferentialouttingflange I5. The lterunit, is formedgfrom the batt Iil in a single stroke of the upper platen I2 with the ring die vI4. As these. f,
elements are forced downwardly, the batt I'misn,
compactedjandcompressed in an annular rimy I6 and by theactionof-heat andpressure the th,er .4 moplastic, fibres. caught beneath theiiat end face, ofthe ringfgdie `are-,fused and made to coalescel A, thereby unifying all the, fibres in'this zone into,v a thin, relatively hard,resilient rim I6 of substane tial=iwidth, for example; one-eighth or one-quarter,1 inch. jfThe body i1, of Afibresdisposed within rim .I6 I'remain substantially. uneifected and con-.M stitute a..relatively-1so ft, uffy I.center portion adapted to perform the filtering operation of the unit.
The single ring die shown in Figs. 1 and 2 produces a filter flat on the face engaged by the platen II and somewhat convex or dome shaped at its other face. In Fig. 4 I have illustrated a double ring die adapted to produce a filter dome shaped at both faces. This die -is like that shown in Figs. land y2 except that a ring I8 is mounted on the platen II opposite to the ring I4. The opposite face portions 20 and 22 of the batt are uncompressed and form the two domes of the filter within the compressed rim 2l, as shown in Fig. 6. A double dome filter of this nature can also be made by cementing together at their rims I6 two filters Il as illustrated in Fig. 5.
In Fig. 7 I have illustrated the making of the filter shown in Fig. 9 and comprising a fabric base 24 of felt or the like bonded tothe vfilter body 26 at the marginal rim 25. The batt IIJ and fabric 24 are placed on the platen II and the lter is formed by one stroke of the top platen i2 in the manner illustrated in Fig. -2. The fabric can also in like manner be applied to the ltop face of 'the iilter if desired and the filter body 29 will in that case be entirely enclosed within bottom and top fabric covers 28 and 30 as illustrated in Fig. l0. The fabric 24 is bonded `to the rim 25 of the body 26 by any suitable method such as incorporating a bonding fibre or element into the fabric or applying an adhesive orthe like thereto.
I have found that the `filter can be produced with a less abrupt break between the fused edge and the dome shaped portion by employing a suitable separator of fabric or paper between the die and the batt in the forming operation, and in "8 I have illustrated such a separator 21 so disposed. When the die descends the separator acts as a surface cushion between the die and batt and produces the product shown in'Fig. 11 and comprising a dome 32 merging more gently into the fused edge 33. It will 'be understood that the separator will be of a composition treated to cooperate with but not adhere to the product.
The body portion of the lter thus farv described is loose, fluffy and wholly uncompressed and is adapted to function with high porosity and permeability. It may be desirable in some cases to yproduce a filter or the like of more compact composition and having decreased porosity and permeability, as the Vlter illustrated in Fig. 12. In Fig. 13 I have illustrated the formation of 'such'a filter by 'employing a relatively shallow ring die 36. When the die descends the batt I within the annular `zone of the die is engaged by the top platen I2 and slightly compressed simultaneously with the compressing vof the lbatt at said zone. The resulting product is -a filter having a somewhat compressed dome with a fiat top surface 34 merginginto the fused edge 35.
VIt will be apparent that 'the blend lof fibres employed will depend upon the function desired of the product and that the shape of the product can be varied to meet requirements. The composition of the batt can be wool, rayon, ramie,
silk and other natural or artificial fibres either alone or in combination with each other, -and in the preferred form of the invention 5% or more of a suitable thermoplastic fibre is added to effect fusing under heat to form the retaining rim I6. For example, the forming of a filter suitable to be employed for vacuum ,cleaner use will utilize a batt constructed by blending 80% of India scribed in detail certain illustrative embodiments.k
cotton with 20% of thermoplastic cellulose acetate fibres as heretofore described. The lters will be formed from the batt merely by the dieing operation herein illustrated and described.
The filters shown in Figs. 9 and 10, having one or more cover layers of felt, flannel or the like at one or both faces, are employed under conditions where it is necessary to provide a filter having an open and porous batt-like face with a reenforcing secondary filter to strengthen the unit and screen out the ne particles which are not trapped by the primary lter.
The weight and thickness of the batt before pressing can be varied to obtain a soft or hard fused edge, a thick or thin product, or one of different density, porosity, and permeability. The porosity,` permeability andv shape of the product can' also be varied by somewhat compressing` the inner filter portion as illustrated in Fig. 13. The filter as thus formed has increased dust Vretention efficiency and decreased porosity and permeability.
-In Fig. 1 `it is suggested that the platen I2 be heated by an electrical heating unit I3 and such construction is satisfactory. Alternatively one or yboth platens may .be steam heated and under those circumstances a convenient cycle has been found to be `a thirty second cycle including five seconds for pressing and cutting at 300 F. and ytwenty-five seconds for opening and closing.
The design of the lower pressing plate is such that the fused 4edge portion is elevated-above the plate so that the unused portion of the batt is` not pressed and may be recarded thus reducing ywaste to a minimum. Further, instead of using an integral pressing and cutting die as shown in Figs. 1 and 2 vasteel ribbon die may be secured to the circumference of the ring-pressing portion of the die.
I-t has been found desirable in some instances to include in the filter a fabricated reinforcing member, forexample, a sheet ofscreen wire. In such instance two carded batts can be run into the press simultaneously with the Screen wire between-them and the three elements pressed and fused into a single filter unit.
While I lhave herein more specifically illustra'ted'and described the production of lter units employing a minor percentage of thermoplastic fibres :adapted lto heat seal 'the marginal portion of the product at It to produce a retaining ring,
it 'will be understood that the invention is applicable to the production of other fibrous units as'gfor example, air conditioning filters, oil filters, auto filters, powder puiis, cosmetic padding devices, etc. with or without the thermoplastic fibres. The subjecting of an annular zone of the batt to pressure between two surfaces determines the marginal border of the product'and effects the bonding of the fibres in the compressed zone to form permanently the retaining ring, and the severing of the outside .portion of the batt from the ring completes the product. When ino thermoplastic fibres are employed the bonding will be Aeffected by suitable adhesives applied to te-zone to be compressed prior to the dieing operation, or by such other method as is found suitable and effective.
'-Ihe process herein disclosed is the subjectmatter of co-'pending application Ser. lo. 49,524, filed September 16,1948, by applicant jointly with Williaml H. Lehmberg and Charles ivi. Foggett.
Having thus disclosed my invention and dethereof, I claim as new and desire to secure by Letters Patent:
1. A fibrous unit comprising a heterogeneous body containing intermingled fusible and non- .fusible fibres, the said fibres being compacted and unied by coalescence of the fusible libres in a thin fiat peripheral rim which is resilient and retains its shape permanently, and being present in the central area of the unit as a uiy relatively thick batt surrounded by the said rim.
2. A fibrous unit comprising a heterogeneous body containing intermingled thermoplastic and non-thermoplastic fibres, the said fibres being compacted and the thermoplastic fibres unified by coalescence in a thin, fiat, relatively hard peripheral rim, and being present within the inner boundary of said rim in a thick, relatively soft batt, certain bres extending from the soft central batt into the harder peripheral rim.
3. A fibrous unit comprising a body containing intermingled fusible and non-fusible fibres and embodying a central area which is relatively soft, thick and pervious to the passage of air and a peripheral zone which is relatively hard, thin and impervious to air and in which the fusible fibres are unified and coalesced in permanent compacted condition.
4. A fibrous unit as described in claim 3, in which one face surface of the unit has a, fabric cover thereover bonded to the unit at said peripheral Zone.
5. A fibrous unit as described in claim 3, in which both face surfaces of the unit have fabric covers thereover bonded to the unit at said peripheral zone.
6. A fibrous unit comprising a body containing intermingled fusible and non-fusible fibres, the mixed fibres forming a central area which is relatively soft, thick and pervious to the passage of air, and said central area merging into a unitary peripheral rim which is relatively hard, thin and impervious to the passage of air and in which the libres are compacted and held in shape by coalescence of the fusible fibres.
7. A fibrous unit comprising two bodies in face to face contact and each containing intermingled fusible and non-fusible fibres forming a central area which is relatively thick and soft and a multi-ply peripheral rim integral with the bodies and relatively hard and in which the bres are held compacted by coalescence of the fusible fibres, the plies of the rim being adhesively united.
8. A fibrous unit comprising a body containing intermingled fusible and non-fusible fibres, the said fibres forming a central area which is i 6 relatively thick and soft, and in which the fusible fibres are substantially free of coalescence, and being compacted and coalesced into a flat relatively stiff thin rim about said area which renders the unit self-contained and self-sustaining, and a fabric cover on at least one face of the unit.
9.` A fibrous unit comprising thermoplastic and j non-thermoplastic fibres mixed heterogeneously and compacted and fused into a relatively hard peripheral rim surrounding a relatively soft and substantially thicker center portion in which the fusible bres are substantially free of coalescence, and a sheet of fabric heat bonded to the said peripheral rim and covering at least one face of the unit.
l0. A filter unit comprising an intermediate, foraminous reinforcing sheet having upon each of its sides a relatively thick, fluffy batt of fusible and non-fusible fibres intermingled throughout the bodyr of the batt and surrounded by a marginal and relatively thin peripheral rim integral with the batts and comprising the marginal portion of the batts in which the fusible fibres are substantially free of coalescence compressed and bonded into a relatively thin retaining ring.
11. A fibrous unit comprising a relatively thick and uiiy batt of fusible and non-fusible fibres intermingled heterogeneously throughout the body of the batt, a fabricated reinforcing sheet intimately associated with the fibres in the batt, and a marginal and relatively thin peripheral rim integral with the batt and supporting the margin of the reinforcing sheet, said rim comprising the marginal portion of the batt in which the fusible fibres are compressed and bonded by heat into a relatively thin retaining ring.
PHILIP I-I. LANG.
REFERENCES CITED rlhe following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,801,949 Broudy et a1 Apr. 21, 1931 1,821,824 Woodward Sept. 1, 1931 2,022,249 Lofgren Nov. 26, 1935 2,035,097 Schwartz Mar. 24, 1936 2,062,834 Schwartz Dec. 1, 1936 2,147,792 Knight Feb. 21, 1939 2,159,121 Alley May 23, 1939 2,232,640 Schwartzman Feb. 18, 1941 2,264,829 Cover Dec. 2, 1941 2,389,435 Karlstroin Nov. 20, 1945 2,433,531 Ryan Dec. 30', 1947 2,438,771 Topjian Mar. 30, 1948
Claims (1)
1. A FIBROUS UNIT COMPRISING A HETEROGENEOUS BODY CONTAINING INTERMINGLED FUSIBLE AND NONFUSIBLE FIBRES, THE SAID FIBRES BEING COMPACTED AND UNIFIED BY COALESCENCE OF THE FUSIBLE FIBRES IN A THIN FLAT PERIPHERAL RIM WHICH IS RESILIENT AND RETAINS ITS SHAPE PERMANENTLY, AND BEING PRESENT IN THE CENTRAL AREA OF THE UNIT AS A FLUFFY RELATIVELY THICK BATT SURROUNDED BY THE SAID RIM.
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Application Number | Priority Date | Filing Date | Title |
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US748983A US2521984A (en) | 1947-05-19 | 1947-05-19 | Fibrous unit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US748983A US2521984A (en) | 1947-05-19 | 1947-05-19 | Fibrous unit |
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US2521984A true US2521984A (en) | 1950-09-12 |
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US748983A Expired - Lifetime US2521984A (en) | 1947-05-19 | 1947-05-19 | Fibrous unit |
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Cited By (54)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2633128A (en) * | 1949-08-26 | 1953-03-31 | Johnson & Johnson | Pad construction and process |
US2639251A (en) * | 1950-03-21 | 1953-05-19 | Aloysius C Kracklauer | Production of filter units for a filter apparatus |
US2711828A (en) * | 1949-09-30 | 1955-06-28 | Chrysler Corp | Plastic fabric filter |
US2760897A (en) * | 1952-06-02 | 1956-08-28 | Us Rubber Co | Weather strip and method of making the same |
US2768026A (en) * | 1953-05-13 | 1956-10-23 | Gustin Bacon Mfg Co | Premolded self-sustaining automobile headliner with air-conditioning ducts |
US2788901A (en) * | 1954-10-11 | 1957-04-16 | American Felt Co | Fused edge filter unit |
US2854974A (en) * | 1953-07-02 | 1958-10-07 | Johnson & Johnson | Pad |
US2878153A (en) * | 1955-02-03 | 1959-03-17 | Agricola Reg Trust | Method of making mattresses, cushions, upholstery, heat and sound insulating coverings and the like |
US2918173A (en) * | 1955-09-06 | 1959-12-22 | Bowser Inc | Multi-cavity cartridge for a filterdehydrator |
US2963744A (en) * | 1956-06-13 | 1960-12-13 | Mcintire Company | Filter element and machine for making same |
US2988169A (en) * | 1957-08-06 | 1961-06-13 | Fiber Bond Corp | Air filter |
US3003581A (en) * | 1957-12-26 | 1961-10-10 | Owens Corning Fiberglass Corp | Fibrous glass air filters |
US3017304A (en) * | 1956-05-24 | 1962-01-16 | Personal Products Corp | Absorbent fibrous structure and method of production |
US3023839A (en) * | 1957-12-26 | 1962-03-06 | Owens Corning Fiberglass Corp | Fibrous glass air filters |
US3109724A (en) * | 1961-01-26 | 1963-11-05 | Richard A Heckman | Filter for high velocity gas streams |
US3154393A (en) * | 1958-04-18 | 1964-10-27 | Fiber Bond Corp | Gas filter |
US3220409A (en) * | 1961-03-28 | 1965-11-30 | Johnson & Johnson | Face mask |
US3237387A (en) * | 1960-04-20 | 1966-03-01 | Skuttle Mfg Co | Filter assembly |
US3273321A (en) * | 1963-08-26 | 1966-09-20 | Cambridge Filter Corp | Air filter having a replaceable cartridge |
US3333404A (en) * | 1966-09-06 | 1967-08-01 | Union Carbide Corp | Filter assembly |
US3353341A (en) * | 1963-05-10 | 1967-11-21 | Tecalemit Engineering | Air filters for internal combustion engines |
US3386413A (en) * | 1966-02-24 | 1968-06-04 | Whitney K. Munson | Inking pad and method of producing the same |
US3388536A (en) * | 1966-09-16 | 1968-06-18 | Johnson & Johnson | Stabilized self-supported filter |
US3388535A (en) * | 1965-02-16 | 1968-06-18 | Johnson & Johnson | Self-supported filter |
US3399516A (en) * | 1965-06-02 | 1968-09-03 | Wix Corp | Impregnated fiber air filter and method of making same |
US3400520A (en) * | 1966-11-16 | 1968-09-10 | Nippon Denso Company Ltd | Filter material for internal combustion engine air cleaner |
US3407576A (en) * | 1966-06-14 | 1968-10-29 | G S Staunton & Company Inc | Self-supporting filter element |
US3451758A (en) * | 1966-05-11 | 1969-06-24 | Procter & Gamble | Trapezoidal scouring pad of non-woven fibrous material |
US3485694A (en) * | 1963-08-26 | 1969-12-23 | Cambridge Filter Mfg Corp | Method for using high frequency heat to make a seam in a filter |
US3499813A (en) * | 1964-11-17 | 1970-03-10 | Scholl Werke Gmbh Fa | Method of making surgical pads |
US3797496A (en) * | 1972-05-06 | 1974-03-19 | Physio Medics Inc | Post-extraction pads |
US3807146A (en) * | 1967-02-21 | 1974-04-30 | H Witkowski | Mold for making a filter |
US3988113A (en) * | 1973-08-17 | 1976-10-26 | Roberts Arnold L | Apparatus for treating engine exhaust gases |
US4084949A (en) * | 1975-11-06 | 1978-04-18 | The Dexter Corporation | Surgical face mask filtering medium |
US4157967A (en) * | 1976-03-25 | 1979-06-12 | Baxter Travenol Laboratories, Inc. | Blood filter |
US4179274A (en) * | 1976-01-07 | 1979-12-18 | Moon William F | Respirator filter and method of making the same |
US4193876A (en) * | 1978-09-27 | 1980-03-18 | Amf Incorporated | Means for suppressing edge leakage in filter presses |
US4272264A (en) * | 1974-08-08 | 1981-06-09 | Multiform Desiccant Products, Inc. | Adsorbent package |
WO1985002351A1 (en) * | 1983-11-23 | 1985-06-06 | Donaldson Company, Inc. | Filter with integral structural framework |
US4600420A (en) * | 1983-11-23 | 1986-07-15 | Donaldson Company, Inc. | Filter with integral structural framework |
US4701197A (en) * | 1986-10-07 | 1987-10-20 | Allied Corp. | Molded panel filter |
US4886526A (en) * | 1987-04-22 | 1989-12-12 | Joannou Costantinos J | Electronic air filtration system |
US4921560A (en) * | 1987-06-18 | 1990-05-01 | J. L. S. Corp. | Method for fixing permanent magnets to cover of bedclothing |
US5178760A (en) * | 1989-04-06 | 1993-01-12 | Solberg Mfg. Co. | Fluid filter construction with a corrugated and tapered filter strip |
US6209542B1 (en) * | 1994-06-03 | 2001-04-03 | W. Keith Thornton | Combination face mask and dental device for improved breathing during sleep |
EP1144070A1 (en) * | 1998-12-03 | 2001-10-17 | Food Equipment Technologies Company, Inc. | Beverage ingredient filter assembly and method |
US20080163595A1 (en) * | 2007-01-09 | 2008-07-10 | Knapp Steven E | Integral Rigid Edging For Synthetic Air Filters |
JP2009509733A (en) * | 2005-10-01 | 2009-03-12 | カール・フロイデンベルク・カーゲー | Filter device |
US20090194907A1 (en) * | 2004-04-22 | 2009-08-06 | Bushey Richard D | Formed felt device and method of making the same |
EP2229993A1 (en) | 2009-03-20 | 2010-09-22 | Nicholas Brentnall | Filter pad and method of manufacture |
US20100237006A1 (en) * | 2009-03-20 | 2010-09-23 | Nicholas Brentnall | Filter and method of manufacture |
WO2012038682A1 (en) * | 2010-09-20 | 2012-03-29 | Nicholas Brentnall | Filter pad and method of manufacture |
WO2012038681A1 (en) * | 2010-09-20 | 2012-03-29 | Nicholas Brentnall | Filter and method of manufacture |
ITMO20130035A1 (en) * | 2013-02-15 | 2014-08-16 | Sarong Spa | METHOD FOR REALIZING A FILTERING ELEMENT |
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US1801949A (en) * | 1928-10-20 | 1931-04-21 | Miles E Heath | Register filter |
US1821824A (en) * | 1929-12-24 | 1931-09-01 | Lewis C Van Riper | Dust collector |
US2022249A (en) * | 1932-10-06 | 1935-11-26 | Electrolux Corp | Vacuum cleaner |
US2035097A (en) * | 1935-06-22 | 1936-03-24 | Schwartz Nathan | Separator for filter type respirators or the like |
US2062834A (en) * | 1935-07-06 | 1936-12-01 | Schwartz Nathan | Filtering device or separator for filter type respirators or the like |
US2147792A (en) * | 1937-04-09 | 1939-02-21 | Zella F Campbell | Filter |
US2159121A (en) * | 1936-06-20 | 1939-05-23 | American Mach & Foundry | Filter tip for cigarettes |
US2232640A (en) * | 1938-12-23 | 1941-02-18 | Protex Products Company | Method of making articles from heat fusible sheet material |
US2264829A (en) * | 1936-05-27 | 1941-12-02 | Harvey S Cover | Respirator |
US2389435A (en) * | 1942-07-09 | 1945-11-20 | Electrolux Corp | Filter material |
US2433531A (en) * | 1940-07-30 | 1947-12-30 | Kendall & Co | Milk filter |
US2438771A (en) * | 1945-02-14 | 1948-03-30 | Topjian Daniel | Garment protector |
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Publication number | Priority date | Publication date | Assignee | Title |
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US1801949A (en) * | 1928-10-20 | 1931-04-21 | Miles E Heath | Register filter |
US1821824A (en) * | 1929-12-24 | 1931-09-01 | Lewis C Van Riper | Dust collector |
US2022249A (en) * | 1932-10-06 | 1935-11-26 | Electrolux Corp | Vacuum cleaner |
US2035097A (en) * | 1935-06-22 | 1936-03-24 | Schwartz Nathan | Separator for filter type respirators or the like |
US2062834A (en) * | 1935-07-06 | 1936-12-01 | Schwartz Nathan | Filtering device or separator for filter type respirators or the like |
US2264829A (en) * | 1936-05-27 | 1941-12-02 | Harvey S Cover | Respirator |
US2159121A (en) * | 1936-06-20 | 1939-05-23 | American Mach & Foundry | Filter tip for cigarettes |
US2147792A (en) * | 1937-04-09 | 1939-02-21 | Zella F Campbell | Filter |
US2232640A (en) * | 1938-12-23 | 1941-02-18 | Protex Products Company | Method of making articles from heat fusible sheet material |
US2433531A (en) * | 1940-07-30 | 1947-12-30 | Kendall & Co | Milk filter |
US2389435A (en) * | 1942-07-09 | 1945-11-20 | Electrolux Corp | Filter material |
US2438771A (en) * | 1945-02-14 | 1948-03-30 | Topjian Daniel | Garment protector |
Cited By (64)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2633128A (en) * | 1949-08-26 | 1953-03-31 | Johnson & Johnson | Pad construction and process |
US2711828A (en) * | 1949-09-30 | 1955-06-28 | Chrysler Corp | Plastic fabric filter |
US2639251A (en) * | 1950-03-21 | 1953-05-19 | Aloysius C Kracklauer | Production of filter units for a filter apparatus |
US2760897A (en) * | 1952-06-02 | 1956-08-28 | Us Rubber Co | Weather strip and method of making the same |
US2768026A (en) * | 1953-05-13 | 1956-10-23 | Gustin Bacon Mfg Co | Premolded self-sustaining automobile headliner with air-conditioning ducts |
US2854974A (en) * | 1953-07-02 | 1958-10-07 | Johnson & Johnson | Pad |
US2788901A (en) * | 1954-10-11 | 1957-04-16 | American Felt Co | Fused edge filter unit |
US2878153A (en) * | 1955-02-03 | 1959-03-17 | Agricola Reg Trust | Method of making mattresses, cushions, upholstery, heat and sound insulating coverings and the like |
US2918173A (en) * | 1955-09-06 | 1959-12-22 | Bowser Inc | Multi-cavity cartridge for a filterdehydrator |
US3017304A (en) * | 1956-05-24 | 1962-01-16 | Personal Products Corp | Absorbent fibrous structure and method of production |
US2963744A (en) * | 1956-06-13 | 1960-12-13 | Mcintire Company | Filter element and machine for making same |
US2988169A (en) * | 1957-08-06 | 1961-06-13 | Fiber Bond Corp | Air filter |
US3003581A (en) * | 1957-12-26 | 1961-10-10 | Owens Corning Fiberglass Corp | Fibrous glass air filters |
US3023839A (en) * | 1957-12-26 | 1962-03-06 | Owens Corning Fiberglass Corp | Fibrous glass air filters |
US3154393A (en) * | 1958-04-18 | 1964-10-27 | Fiber Bond Corp | Gas filter |
US3237387A (en) * | 1960-04-20 | 1966-03-01 | Skuttle Mfg Co | Filter assembly |
US3109724A (en) * | 1961-01-26 | 1963-11-05 | Richard A Heckman | Filter for high velocity gas streams |
US3220409A (en) * | 1961-03-28 | 1965-11-30 | Johnson & Johnson | Face mask |
US3353341A (en) * | 1963-05-10 | 1967-11-21 | Tecalemit Engineering | Air filters for internal combustion engines |
US3273321A (en) * | 1963-08-26 | 1966-09-20 | Cambridge Filter Corp | Air filter having a replaceable cartridge |
US3485694A (en) * | 1963-08-26 | 1969-12-23 | Cambridge Filter Mfg Corp | Method for using high frequency heat to make a seam in a filter |
US3499813A (en) * | 1964-11-17 | 1970-03-10 | Scholl Werke Gmbh Fa | Method of making surgical pads |
US3388535A (en) * | 1965-02-16 | 1968-06-18 | Johnson & Johnson | Self-supported filter |
US3399516A (en) * | 1965-06-02 | 1968-09-03 | Wix Corp | Impregnated fiber air filter and method of making same |
US3386413A (en) * | 1966-02-24 | 1968-06-04 | Whitney K. Munson | Inking pad and method of producing the same |
US3451758A (en) * | 1966-05-11 | 1969-06-24 | Procter & Gamble | Trapezoidal scouring pad of non-woven fibrous material |
US3407576A (en) * | 1966-06-14 | 1968-10-29 | G S Staunton & Company Inc | Self-supporting filter element |
US3333404A (en) * | 1966-09-06 | 1967-08-01 | Union Carbide Corp | Filter assembly |
US3388536A (en) * | 1966-09-16 | 1968-06-18 | Johnson & Johnson | Stabilized self-supported filter |
US3400520A (en) * | 1966-11-16 | 1968-09-10 | Nippon Denso Company Ltd | Filter material for internal combustion engine air cleaner |
US3807146A (en) * | 1967-02-21 | 1974-04-30 | H Witkowski | Mold for making a filter |
US3797496A (en) * | 1972-05-06 | 1974-03-19 | Physio Medics Inc | Post-extraction pads |
US3988113A (en) * | 1973-08-17 | 1976-10-26 | Roberts Arnold L | Apparatus for treating engine exhaust gases |
US4272264A (en) * | 1974-08-08 | 1981-06-09 | Multiform Desiccant Products, Inc. | Adsorbent package |
US4084949A (en) * | 1975-11-06 | 1978-04-18 | The Dexter Corporation | Surgical face mask filtering medium |
US4179274A (en) * | 1976-01-07 | 1979-12-18 | Moon William F | Respirator filter and method of making the same |
US4157967A (en) * | 1976-03-25 | 1979-06-12 | Baxter Travenol Laboratories, Inc. | Blood filter |
US4193876A (en) * | 1978-09-27 | 1980-03-18 | Amf Incorporated | Means for suppressing edge leakage in filter presses |
WO1985002351A1 (en) * | 1983-11-23 | 1985-06-06 | Donaldson Company, Inc. | Filter with integral structural framework |
US4600420A (en) * | 1983-11-23 | 1986-07-15 | Donaldson Company, Inc. | Filter with integral structural framework |
US4701197A (en) * | 1986-10-07 | 1987-10-20 | Allied Corp. | Molded panel filter |
US4886526A (en) * | 1987-04-22 | 1989-12-12 | Joannou Costantinos J | Electronic air filtration system |
US4921560A (en) * | 1987-06-18 | 1990-05-01 | J. L. S. Corp. | Method for fixing permanent magnets to cover of bedclothing |
US5178760A (en) * | 1989-04-06 | 1993-01-12 | Solberg Mfg. Co. | Fluid filter construction with a corrugated and tapered filter strip |
US6209542B1 (en) * | 1994-06-03 | 2001-04-03 | W. Keith Thornton | Combination face mask and dental device for improved breathing during sleep |
EP1144070A1 (en) * | 1998-12-03 | 2001-10-17 | Food Equipment Technologies Company, Inc. | Beverage ingredient filter assembly and method |
EP1144070A4 (en) * | 1998-12-03 | 2002-04-10 | Food Equip Technologies Co Inc | Beverage ingredient filter assembly and method |
US20090194907A1 (en) * | 2004-04-22 | 2009-08-06 | Bushey Richard D | Formed felt device and method of making the same |
US9339953B2 (en) * | 2004-04-22 | 2016-05-17 | Richard D. Bushey | Method of making a formed felt device |
JP2009509733A (en) * | 2005-10-01 | 2009-03-12 | カール・フロイデンベルク・カーゲー | Filter device |
US20080163595A1 (en) * | 2007-01-09 | 2008-07-10 | Knapp Steven E | Integral Rigid Edging For Synthetic Air Filters |
US7517378B2 (en) * | 2007-01-09 | 2009-04-14 | Knapp Steven E | Integral rigid edging for synthetic air filters |
EP2229993A1 (en) | 2009-03-20 | 2010-09-22 | Nicholas Brentnall | Filter pad and method of manufacture |
US20100237006A1 (en) * | 2009-03-20 | 2010-09-23 | Nicholas Brentnall | Filter and method of manufacture |
US20100237005A1 (en) * | 2009-03-20 | 2010-09-23 | Nicholas Brentnall | Filter pad and method of manufacture |
EP2239033A1 (en) * | 2009-03-20 | 2010-10-13 | Nicholas Brentnall | Filter and method of manufacture |
CN103458986A (en) * | 2010-09-20 | 2013-12-18 | N·布兰特纳尔 | Filter pad and method of manufacture |
WO2012038681A1 (en) * | 2010-09-20 | 2012-03-29 | Nicholas Brentnall | Filter and method of manufacture |
CN103492043A (en) * | 2010-09-20 | 2014-01-01 | N·布兰特纳尔 | Filter and method of manufacture |
RU2548438C2 (en) * | 2010-09-20 | 2015-04-20 | Николас БРЕНТНАЛЛ | Filtering gasket and method of manufacturing |
CN103458986B (en) * | 2010-09-20 | 2015-08-19 | N·布兰特纳尔 | Filtration liner and manufacture method thereof |
WO2012038682A1 (en) * | 2010-09-20 | 2012-03-29 | Nicholas Brentnall | Filter pad and method of manufacture |
ITMO20130035A1 (en) * | 2013-02-15 | 2014-08-16 | Sarong Spa | METHOD FOR REALIZING A FILTERING ELEMENT |
WO2014125440A1 (en) * | 2013-02-15 | 2014-08-21 | Sarong Societa' Per Azioni | Method for making a filtering element and filtering element |
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